text:
Four years have passed since Google kingpin Eric Schmidt resigned from the Apple board of directors, signaling the start of what you might call a cold war between the two tech giants.
Or perhaps cold is the wrong word.
Six months after Schmidt left Apple's board, Steve Jobs laid into Google during an Apple town hall meeting, crying foul over Android's challenge to the iPhone and recasting the search giant's "Don't Be Evil" motto as "bullshit." Throughout 2010 and into 2011, the two companies publicly sparred over whose smartphone technology was the most "open" and whose would ultimately make life easier for humankind. Then, in 2012, Apple summarily removed Google Maps and YouTube from the iPhone, determined to reduce its dependance on the company that so quickly usurped its command of the mobile market.
Schmidt now says there's detente between the two, but even if that's true, it didn't come soon enough to avoid a very real divorce of technologies. Until recently, the two companies shared one of the world's most important open source software projects – WebKit, the basis for Apple's Safari browser and Google's Chrome – but then, in April, that marriage ended too. Once so close, Apple and Google are now as far apart as anyone in the high-stakes tech game.
And yet, there's one thing they still have in common, one last piece of technological brilliance they freely share with each another.
Chances are, you've never heard of it. But nowadays, it's an integral part every new Apple iPhone – and every new Android phone. It's not an app or a web service or some sort of hardware contraption. It's more important than that. It's a tool that's changing the way we build and run computer software – any computer software.
This tool is known as LLVM, short for low level virtual machine. But don't let that throw you. The acronym isn't even an accurate description of what the thing does. It's just a name. The thing to realize is that LLVM underpins so much of the work at both Apple and Google, helping create not only smartphone software, but operating systems and browsers and web services.
"At first, it was this crazy experiment," says Chandler Carruth, one of the Google software engineers charged with building the software development tools used by every engineer at Google. But about a year into that experiment, LLVM was there to stay. "The teams that were on it started to be able to change and evolve and develop at a much more rapid pace."
Created by a team of researchers at the University of Illinois at Urbana-Champaign, LLVM is a way of building software compilers – those contraptions that receive raw code from the world's programmers and convert it into real, live software applications. But it's more than that. It's also a better way of executing software applications on PCs and smartphones and tablets and other hardware. It lets you run programs on machines and microprocessors they weren't explicitly written for.
Today, Apple uses LLVM to build its desktop and notebook operating system, Mac OS X, as well as its iOS operating system, used by smartphones and tablets. The tool is at the heart of the Apple Xcode software that outside developers use to build applications for all these machines. Likewise, it helps build and run applications for Google Android phones, but inside Google, it also helps create the software that underpins the company's online empire, the software that runs services like Google Search, Gmail, and Google Docs.
In June, LLVM received the prestigious ACM Software Award, following in the footsteps of the operating system that gave rise to modern computing, the protocols that drive the internet, and the browser that took the web mainstream. But it's only just getting started. The hope is that LLVM will usher in a new era of software development where applications can freely move from machine to machine and even from processor to processor.
With a fledgling technology it calls Portable Native Client, Google already is moving down this path on desktops and notebooks, and at the University of Illinois at Urbana-Champaign, one of LLVM's creators, computer science professor Vikram Adve, is leading a team that aims to take the idea even further on smartphones and tablets.
"There should be an industry standard for how code is shipped and executed, so that it would just work on different combinations of hardware," Adve says. "LLVM is already being used by both the major players – Apple and Google – so it's the natural foundation to build on."
Write Once, Run Anywhere. Please ——————————–
The software nirvana that Vikram Adve describes is hardly a new idea. In the late 1990s, this was the goal of Java, the open source programming platform created at Sun Microsystems. For years, the Java mantra was "write once, run anywhere."
The rub is that JavaScript is a relatively simple language. It can't do everything other languages can do, including Java and those venerable creations, C and C++. What we need is a way of running any application, written in any language, on any machine, without a whole lot of compromise – and that's where LLVM is headed, at least in the eyes of some.
LLVM was born in late 2000, when Chris Lattner, a graduate student working under Vikram Adve at the University of Illinois, flew for home for Christmas. At one point, he and Adve had discussed the idea of building a new kind of Java that would solve many of the platform's inherent problems, and over his holiday break, Lattner turned the idea into a prototype. This was the seed of LLVM, and it was remarkably similar to what the tool would later become.
One of the strengths of Java is what's called "just-in-time" compilation. If you're a developer and you write a Java program, you don't compile it into a finished application on your own machine before shipping it off to the rest of the world. You compile it into something called "bytecode" and ship that off to its ultimate destination. Sitting atop something called a virtual machine, this bytecode is then compiled as it executes. In other words, your program compiles on the hardware that runs it, as it runs.
This is a bit like having your clothes stitched together as you put them on. A Java program gets tailored to the particular hardware where it's running – at least to a certain extent.
What Chris Lattner and Vikram Adve wanted to do was take this idea significantly further. Java lets you move applications from hardware device to hardware device, but you can't tailor a program to the hardware the way you can with machine code – the language spoken by the machine itself. Lattner and Adve wanted something that behaved like Java – but also like machine code.
The prototype was called LLVM, which stood for "low-level virtual machine." It would be "low-level" like machine code – running very close to the hardware – but it would also allow for portable applications, much like the Java virtual machine. But the acronym was quickly eclipsed, as LLVM took on a much greater role, expanding beyond that original idea.
You Can Build ... Whatever You Want ———————————–
By the middle of the decade, Lattner and Adve and other engineers had turned LLVM into what you can think of as a developer toolkit for building developer toolkits. It was a collection of software "libraries" – software building blocks – that anyone could use to build their very own custom compiler. "It's a modular compiler infrastructure," says Michael Larabel, a developer who has worked with LLVM for years. "You can have all these different front-ends."
It wasn't limited to Java. You could build a compiler that handled practically any language, and you could arrange for compilation at practically any point in the lifecycle of a program, including Java-like just-in-time compilation. "The key technical innovation was the ability to compile virtually any language to a bytecode form that could be optimized at any point you choose," Adve says.
What's more, the project was shared with the world at large under what's called a permissive open source license. This means that anyone could change these libraries and incorporate them into their own software – without returning those changes and that software to the open source community.
In short, LLVM let you do whatever you wanted in building a compiler – and that's why Apple hired Chris Lattner in 2005.
With LLVM, Apple had the technical means to build a compiler that suited all of its needs, and it could merge this compiler with the rest of Xcode – truly merge it – without open sourcing Xcode and sharing its proprietary software with the rest of the world.
Lattner declined to be interviewed for this story, saying that Apple frowns on employees talking to the press without approval. But it's no secret that LLVM is now at the heart of Apple's development philosophy, largely replacing the old GCC compiler, which isn't as flexible or as powerful as LLVM – and lacks a permissive license.
Thanks to Lattner's online resume and other sources, we know that LLVM is "deeply integrated" with Xcode, and that it was used to build the latest versions of Mac OS X and iOS. What's more, it's used to compile graphics code, in real-time, on iPhones and iPads, perhaps hinting at where the company will take it in the future.
The Biggest Supercomputer of Them All ————————————-
But Apple isn't the only one. LLVM remains an open source project – headed by Lattner. Sony now uses LLVM to compile code for its PlayStation gaming console. Cray taps the tool in building software for its supercomputers. And Google uses it to fashion software for the biggest supercomputer of them all: the Googlenet, that worldwide network of machines that runs all the company's web services.
Using LLVM, Google has built all sorts tools that seek to streamline development of the company's internal software. This includes small stuff, like, say, a tool that automatically checks for coding errors and another that automatically formats your code so it's easier to read with the human eye. But it also includes some rather big stuff.
Google is unusual in that all software code that underpins its many applications and services is available to every developer at the company. What this means is that anyone can reuse anyone else's code inside their own application or service. That's powerful thing, but not long after moving to this model, Google had problem.
"Imagine you've built a library, a pretty low-level library, some core piece of Google's infrastructure. You're got thousands and thousands of servers being built using it," says Google engineer Chandler Carruth. "Now, what if when you want to change that library? How do you do that? How do you improve it? Everyone is depending on you. Everyone is impacted. They've all written code that pins down exactly how your library works. How do you change it?"
For a while, it was an nightmare. But then, using LLVM and the sweeping infrastructure that runs the Google Search engine, Carruth and his team built a system that could, yes, automate the process. This system indexes all Google code, in much the same way Google indexes the web, and then, when an engineer rewrites a library, the system instantly searches the index, locates any software that uses the library, and makes the necessary adjustments. A change made in one place becomes a change made everywhere.
The setup, Carruth says, has turned Google into an operation where code is truly universal. "We had kind of this pendulum swing. People got real excited about the unified codebase, being about to share all of our libraries, but then it swung the other way and people were afraid, because the most important libraries got to the point where we couldn't change them anymore, they were too shared," he explains. "But now the pendulum has swung back again."
Apple and Google Together Again? ——————————–
Considering the size of Google's operation, this is a wonderfully impressive hack. But like Vikram Adve back at the University of Illinois, the company wants more out of LLVM. It wants to achieve something akin to that "write once, run anywhere" nirvana.
The search giant is also using LLVM to create a tool that can safely run any code inside a browser on practically any machine. Still under development, this tool is known as Portable Native Client, and you can think of it as a kind of uber browser plug-in. In many ways, it echoes the original goal laid down by Lattner and Adve: a programming paradigm somewhere between Java and machine code.
"If you look at the way Android apps work today, they can only use the main processor on each of the Android devices. But Android devices use a bunch of other hardware, like the graphics processor, the digital signal processor, and other more-optimized computing hardware," he says. "One major problem is how you can allow these applications to take advantage of this rich set of hardware that comes with every cellphone."
LLVM, he says, is in just the right position not only to solve this problem, but to solve it in a standard way – in a way that unites the smartphone, freeing applications from the phones of any one company. After all, LLVM is already use by the world's two biggest smartphone players: Apple and Google.
But then he has a second thought. "Maybe Google and Apple will come up with different methods," he says, "which is actually quite likely, given their history."


text:
PHNOM PENH, Cambodia
Svay Pak is a hellhole, a dirty, stinking slum of about 4,000 people. It's also notorious for being one of few places where men can pay for sex with children as young as three.
When Pastor Chantha Hem, his wife, Bunthan, and their baby son came here three years ago from Phnom Penh, they moved into a former brothel. Their pink room, upstairs, had been reserved for the raping of virgins.
Downstairs, there were bare-walled cells with wooden slatted beds and sleeping mats that had been rented out by the hour, mostly to foreign men who wanted to have sex with children.
"I am not just a pastor," Hem says. "We try to stop child trafficking. Sometimes we confront traffickers and gangsters. This is my challenge ...
"The foreigners come night and day. Sometimes I pretend like a pimp and we have communications with them and we try to record it and we try to get information to give to the police. It is very dangerous. But we have to try to stop this."
The pastor says 90 per cent of an estimated 2,000 children in this village have been sold to a pimp or a brothel owner and been sexually abused.
"Most are abandoned by their parents and live with their grandparents or a neighbour or some other relative. The moms are gone ... It's very difficult to forgive the parents."
Among his 250 parishioners, Hem says 12 or 13 are former brothel owners — both men and women. Among their business partners, he says, were government officials and even army officers.
"They told me that when you sell children who are five, six, seven or eight years old, you feel shame. Your heart feels guilty ... But now they come to church. Some are doing good [things] and some are still doing bad things."
The village, however, has changed.
Because of Hem's work and other programs funded by Vancouver-based Ratanak International and California-based Agape International Missions, children now have a safe place to go during the day. When AIM took applications for the school it runs, 2,000 children applied along with six villagers in their 80s who had never had the chance before.
The general health of the community has been improved because of AIM's twice-weekly medical clinic and an annual dental clinic, staffed by American volunteers who fly in and work for a week.
But it hasn't ended the sexual exploitation. It's driven it underground, making it harder to detect.
"During the day, you see many girls here. At night, you hardly see any. The brothels, they keep them secretly and move them around from one place to another. Some of them go mostly by [motorcycle] to Phnom Penh at night. But from here they are also sent to Siem Reap and Sihanoukville," says Hem.
As rewarding as the work is, it may get the pastor killed.
"Many times people have tried to kill me. Right now, every night, they stone my door. They are drunk and have been taking drugs. 'Come out, we want to kill you,' they say. I trust Jesus. God has called us to come here and I believe God will protect us.
"Sometimes I feel afraid. When I pray to God I ask him to protect us."
Ever since he arrived, Hem's had death threats.
People accuse him of coming here to ruin their business — the business of selling in children.
According to the 2011 U.S. State Department's Trafficking in Persons report — which specifically mentions the child sex trafficking ring in Svay Pak — that business is being run by people "believed to be well-connected and protected from effective government investigation and prosecution."
The threats against Hem intensified after he rescued two five-year-old girls — one in 2010 and the other late last year — by notifying police that both were about to be sold into sex slavery.
The most recently rescued girl is now in a safe house. Her mother is in jail.
Hem finds it hard to accept his neighbours who sell their own children. But the foreigners who come here to buy them trouble him more.
"They are so rich and they use their money in the wrong way. Why don't they use their money to help the people? Why don't they use their money for good? This is the wicked thing in Cambodia."
Daily kids camp
One of the first things the pastor did when he moved here in 2006 was set up a daily kids camp, a safe place for children to come, play games, sing songs and forget even for a few hours the misery of their lives.
At first, only 16 kids showed up.
"People would not allow their kids to come. So, I would knock on their doors day by day and more and more would come together. At first it was very hard work. We didn't know anybody and they don't know Jesus, they had their own culture and religion. They were used to gambling, alcohol and abusing girls.
"At first, I tried to build a relationship between them and us. I would go and hang around every day. We would try to help them. Even if he's a bad guy, I kept telling myself that God still loves him."
Soon, the number of kids had doubled. Now, there are days when as many as 500 children attend kids club or the twice-weekly medical clinic — or simply show up to watch cartoons and have some lunch or a snack. Attendance at Sunday church services also increased, to the point that the congregation outgrew the former brothel that had been renamed Rahab's House.
In 2010, AIM — with funds from Ratanak International — rented a bigger building on the main street. It was to have been a brothel and hotel. It's now called The Sanctuary.
Moved in eight years ago
Californians Don and Bridget Brewster, who founded Agape International Missions eight years ago, moved into The Sanctuary a year ago. They moved to the top-floor apartment from Phnom Penh, where they'd been living at the organization's trauma recovery house for rescued girls.
Since opening that safe house in 2006, nearly 200 girls have benefited from the intensive counselling, education and training offered there.
Among them are at least one of the victims of Canada's first convicted sex tourist, Donald Bakker, and seven girls whose testimony in a California court resulted in ex-Marine and sex tourist Michael Pepe being sentenced to more than 100 years in prison.
Although their home is called The Sanctuary, Bridget admits that it's frightening to receive nightly death threats and that she frequently cries in the shower where no one can see or hear her.
"It's the Wild West here ... The other night there was a machete fight outside with boys and girls all drugged up fighting. It's a little crazy."
While we talked, the noise at times was almost deafening as about 175 children laughed, screamed and sang their way through kids club.
"I think the worst that I've seen is some bloody clothes from a little girl who had been raped during the day," says Bridget. "A man took her out behind The Sanctuary, behind that big bougainvillea tree, and raped her. Then, she came here."
But there are successes that make the work worthwhile. One of the rescued girls has now returned to Svay Pak, where she runs her own sewing business and will soon be married.
Still, Bridget says the best thing is seeing kids being kids.
"I never knew how cruel a person could be to totally devalue then totally rob a child of innocence. But to see these girls laugh and be kids again is a look into the future."
Still, that future is far from guaranteed.
On a second trip to Svay Pak, we walked out of Rahab's House — where a group of American dentists (many former Vietnam veterans) were working in conditions that looked like a scene from the old television show M*A*S*H — to see four young Americans hunting for children.
Noticing us, the Americans urged the driver of their tuk-tuk — a motorcycle-powered cart — to turn around.
Several people snapped photos of them. A couple of missionary volunteers jumped on motorbikes to follow them.
Will they be charged? Not likely.
It's not a crime to go to Svay Pak, even though Svay Pak is nothing like Bangkok's notorious Patpong where tourists now go to shop and take a look at what was once the heart of Southeast Asia's child sex trade.
There are no signs on the paved road pointing to the small, bumpy trail that passes for Svay Pak's main street. Even most tuk-tuk, moto and taxi drivers — the decent ones — don't know how to get here.
It's not surprising. There are only two reasons come.
One is to have sex with children; the other is to rescue them.

subset: commoncrawl


text:
Patent application title: TUBULAR MEDICAL ENDOPROSTHESES
Kevin R. Heath (Providence, RI, US)
IPC8 Class: AA61F282FI
USPC Class:
623 134
Class name: Prosthesis (i.e., artificial body members), parts thereof, or aids and accessories therefor arterial prosthesis (i.e., blood vessel) having marker (e.g., color, radiopaque, etc.)
Publication date: 2010-03-18
Patent application number: 20100070025
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Patent application title: TUBULAR MEDICAL ENDOPROSTHESES
Kevin R. Heath
Boston Scientific Scimed, Inc.
Origin: MINNEAPOLIS, MN US
IPC8 Class: AA61F282FI
USPC Class:
623 134
Patent application number: 20100070025
A tubular prosthesis device for use within the body. The device includes,
a metal filament material formed of metal outer member having an exposed
outer surface and a core within the extended outer member formed of a
different metal than the outer member. The core is secured within and
substantially enclosed by the outer member. The device can be reduced to
a small size for introduction into the body lumen and expandable to a
sufficiently large size to engage the wall of the body lumen. Stents
formed of composite wires are shown.
1-30. (canceled)
31. An implantable medical stent, comprising:a first layer;a second layer; anda third layer,wherein a radiopacity of the first layer is different from a radiopacity of the second layer.
32. The implantable medical stent of claim 31, wherein the radiopacity of the first layer is less than the radiopacity of the second layer.
33. The implantable medical stent of claim 32, wherein the first layer is disposed inwardly of the second layer.
34. The implantable medical stent of claim 33, wherein the second layer is disposed inwardly of third layer.
35. The implantable medical stent of claim 31, wherein the first layer comprises stainless steel.
36. The implantable medical stent of claim 31, wherein the second layer comprises a metal selected from the group consisting of tungsten, tantalum, rhenium, iridium, silver, gold, bismuth, platinum and alloys thereof.
37. The implantable medical stent of claim 31, wherein the second layer comprises a material having a density of 9.9 grams per cubic centimeter or greater.
38. The implantable medical stent of claim 31, wherein the second layer comprises a material having a density of 16 grams per cubic centimeter or greater.
[0001]This application is a continuation of U.S. application Ser. No. 10/751,749, filed Jan. 5, 2004, which is a continuation of application Ser. No. 09/924,275, filed Aug. 8, 2001, now U.S. Pat. No. 7,101,392, which is a continuation of U.S. application Ser. No. 09/076,520, filed May 12, 1998, now U.S. Pat. No. 6,287,331, which is a continuation of U.S. application Ser. No. 08/955,268, filed Oct. 21, 1997, now U.S. Pat. No. 6,290,721, which is a continuation of U.S. application Ser. No. 08/478,007, filed Jun. 7, 1995, now abandoned, which is a continuation of U.S. application Ser. No. 08/282,776, filed Jul. 29, 1994, now abandoned, which is a continuation of U.S. application Ser. No. 07/910,631, filed Jul. 8, 1992, now abandoned, which is a continuation-in-part of U.S. application Ser. No. 07/861,253, filed Mar. 21, 1992, now abandoned.
[0002]This invention relates to tubular endoprostheses to be used inside the body.
[0003]Tubular endoprostheses such as medical stents are placed within the body to perform a function such as maintaining a body lumen open, for example, a passageway occluded by a tumor or a blood vessel restricted by plaque. Tubular endoprostheses in the form of grafts are used to substitute for or reinforce a lumen, such as the aorta or other blood vessels which have been weakened, e.g., by an aneurysm.
[0004]Typically, these endoprostheses are delivered inside the body by a catheter that supports the device in a compacted or otherwise reduced-size form as it is transported to the desired site. The size is particularly small when a percutaneous insertion technique is employed. Upon reaching the site, the endoprosthesis is expanded so that it engages the walls of the lumen.
[0005]The expansion mechanism may involve forcing the endoprosthesis to expand radially outwardly, for example, by inflation of a balloon carried by the catheter, to plastically deform and fix the device at a predetermined expanded position in contact with the lumen wall. The expanding means, the balloon, can then be deflated and the catheter removed.
[0006]In another technique, the endoprosthesis is formed of a highly elastic material that can be reversibly compacted and expanded. During introduction into the body, the endoprosthesis is restrained in the compacted condition and upon reaching the desired site for implantation, the restraint is removed, enabling the device to self-expand by its own internal elastic restoring force.
[0007]In many cases, X-ray fluoroscopy is used to view an endoprosthesis within the body cavity to monitor placement and operation. The device may also be viewed by X-ray film after placement for medical follow-up evaluation. To date, the requirement for radiopacity has limited the construction of devices to certain materials which in turn has limited the features attainable for particular applications and the available insertion techniques.
[0008]In the invention, metal such as in the form of wire or filament or the like is used for constructing tubular medical endoprosthesis such as stents. Desirable attributes of these wires vary with the stent application, but include properties such as stiffness, tensile strength, elasticity, radiopacity, weldability, flexural life, conductivity, etc. These properties are hard to find in conventional wires. According to the invention, desired properties are achieved by creating a multiple metal coaxial construction. For example, it may be very desirable to have high radiopacity along with elasticity and strength. This is accomplished by combining a radiopaque metal with an elastic metal. Although it is possible to put either metal on the inside or outside, it is preferable to put the dense radiopaque material (e.g., tantalum) on the inside (core) since dense materials are generally less elastic and the elastic material (e.g., titanium or nickel-titanium alloy) on the outside (clad). The clad or "skin" of the wire will undergo more deformation in bending than the core, so the elastic component is best positioned at the skin.
[0009]Thus, an aspect of the invention is a metal stent device with at least a portion to be used within the body having properties that can be tailored to a particular application. The portion within the body is formed of preferably two or more dissimilar metals joined together to form a unitary member. Typically, each metal contributes a desirable property to the device which is not substantially impaired by the presence of the other metal. In particularly preferred devices, one metal provides enhanced radiopacity. In these embodiments, the stent is comprised of a metal outer member having a predetermined density and an exposed outer surface and a core including a metal having a density greater than the outer member to enhance radiopacity. The core is secured within and substantially enclosed by the outer member. Preferably, the stent is configured such that the mechanical properties, for example, the elastic properties, of the metal forming the outer member are affected by the core to a desired degree so that the stent has a desired overall performance suitable for its intended use. Preferably, the mechanical properties of the outer member dominate the properties of the stent yet the radiopacity of the member is substantially enhanced by the denser core. The invention also allows increased radiopacity of the stent without adversely affecting and in some cases improving other important properties such as the biocompatibility, small size or other performance characteristics. These performance advantages can be realized by proper selection of the material of the outer member and core, their relative size, and geometrical configuration. The particular performance characteristics to be achieved are dictated by the stent application.
[0010]The term "metal" as used herein includes electropositive chemical elements characterized by ductility, malleability, luster, and conductivity of heat and electricity, which can replace the hydrogen of an acid and forms bases with the hydroxyl radical and including mixtures including these elements and alloys. Many examples are given below. An aspect of the invention features a tubular prosthesis device for use within the body. Forming the tubular endoprosthesis is a metal filament material comprised of a metal outer member of extended length having an exposed outer surface and a core within the extended outer member formed of a different metal than the outer member. The core is secured within and substantially enclosed by the outer member. The device is capable of reduction to a small size for introduction into the body lumen and expandable to a sufficiently large size to engage the wall of the body lumen.
[0011]In some preferred embodiments, the outer member and core are such that the endoprosthesis is elastic and capable of radial reduction in size without plastic deformation to the small size for introduction to the body and self-expandable by an internal elastic self-restoring force to the large size for engaging the wall of the lumen.
[0012]In other embodiments, the outer member and core are such that the endoprosthesis is plastically deformable; it is formed of small size for introduction into the body and expandable by plastic deformation to the large size for engaging the wall of the lumen.
[0013]Various embodiments of the invention may also include one or more of the following features. The device is formed into the tubular shape by knitting of the wire or filament into loosely interlocked loops of the filament. The metal of the core has a density greater than the metal of the outer member of the device. The cross sectional dimension of the filament is about 0.015 inch or less. The cross-sectional dimension of the filament is about 0.006 to about 0.0045 inch and the core has a cross-sectional dimension of about 0.0014 to about 0.00195 inch. The core has a density of about 9.9 g/cc or greater. The core is selected form the group consisting of tungsten, tantalum, rhenium, iridium, silver, gold, bismuth and platinum. The outer member is selected from superelastic alloys and precursors of superelastic alloys and stainless steel. The outer member is nitinol. The core is tantalum.
[0014]Another, particular aspect of the invention features a self-expanding tubular prosthesis device for use within the body formed of loosely interlocked knitted loops of a metal filament material. The filament is formed of an elastic metal capable of deflection without plastic deformation to produce a self-restoring force. The filament material is formed of an elastic metal outer member of extended length having high elasticity and an exposed outer surface, and a core of a different metal than the outer member, which core is secured within and substantially enclosed by the outer member. The device is capable of reduction to a small size for introduction into the body lumen and expandable by the internal restoring force to a sufficiently large size to engage the wall of the body lumen.
[0015]Various embodiments of this aspect as well as other aspects may include the features already mentioned as well as one or more of the following features. The core is about 25% or more of the cross-sectional dimension. The core is between about 1 and 40%, e.g. about 28% or less, preferably 33% of the cross-sectional dimension. The core has a modulus of elasticity of about 500 GPa or less, such as about 200 GPa or less.
[0016]In another aspect the invention features a medical stent device capable of placement or manipulation in the body by means external of the body under guidance of a fluoroscope. The device is at least in part an elongated filament-form metal member adapted to be subjected to elastic deformation to enable the device to be forced into a characteristic deformed configuration during a stage of use and to elastically self-recover from the deformation when deformation forces are relieved. The filament-form metal member includes a core of a first metal of a first selected thickness and an intimately surrounding sheath of a second selected metal of a second thickness. The first metal is a high density metal that demonstrates characteristic relatively high radiopacity and the second metal is a lower density metal having substantially more elasticity than the first metal. The combined effect of the selected thicknesses of the first and second metals in the filament-form member serves to enhance the radio-opacity of the filament-form member to provide improved fluoroscopic or x-ray visualization of the filament-form member in the body while imparting sufficient elasticity to enable the filament-form member to elastically self-recover from its characteristic deformed configuration.
[0017]In another aspect, the invention features a tubular endoprosthesis formed of a metal member. The metal member has a cross-sectional thickness of about 0.015 inch or less, more preferably 0.0075 inch or less, and is composed of at least two different metals, including an exposed outer metal having selected mechanical properties and an inner metal encompassed within the outer metal, the inner metal having a relatively high density compared to the outer metal for enhancing the radiopacity of the endoprosthesis.
[0018]In various embodiments of any of the aspects of the invention the filament is formed by draw-forming techniques employing a large starting member which has a core of metal of different properties than a surrounding metal shell.
[0019]The invention also includes methods for the use and construction of the endoprostheses described.
[0020]Still other aspects of the invention will be understood from the following description and from the claims. cl DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0021]We first briefly describe the drawings.
[0022]FIG. 1 is a perspective view of a stent according to the invention, while FIG. 1a is an enlarged view of adjacent loops of a filament knitted to form the stent;
[0023]FIG. 2 is a highly enlarged schematic cross-sectional view of the stent filament in FIG. 1a across the lines 22; while FIG. 2a is a similarly enlarged longitudinal cross-sectional view of a portion of the filament;
[0024]FIG. 3 is a schematic longitudinal cross-sectional view of a stent filament according to FIG. 2 in a bent configuration;
[0025]FIGS. 4 to 4b illustrate placement of a self-expanding stent according to the invention;
[0026]FIGS. 5 to 5b illustrate placement of a plastically deformable stent according to the invention;
[0027]FIG. 6 is a graph of load as a function of displacement for several stent wires according to the invention.
[0028]FIG. 7 is an enlarged schematic cross-sectional view of a stent filament.
[0029]Referring to FIGS. 1 and 1a, an endoprosthesis stent 10 according to a preferred embodiment is adapted for use in the biliary tree and formed of an elastic filament 11 knitted into a mesh cylinder 12 that extends to ends 14, 14' coaxially along axis 13 over a working length L, about 4-6 cm and has a maximum expanded diameter, D, of about 9-10 mm. The knitting forms a series of loosely interlocked knitted loops (e.g., as indicated by adjacent loops 16, 16', FIG. 1a) which may slide with respect to each other when the stent is radially compacted, for example, when delivered into the biliary duct on a catheter as further discussed below.
[0030]Referring to FIGS. 2 and 2a, the filament 11 is a wire-form member that includes a longitudinal outer member 4 concentrically disposed about a central core 8 which extends along an axis 6. The longitudinal member 4, having an outer diameter, do about 0.0052 inch, is formed of a metal, such as nitinol, that exhibits desirable properties, such as high elasticity and biocompatibility of its exposed outer surface 7. (The surface 7 may include a non-metal coating of, e.g., fluorocarbons, silicones, hydrophilic and lubricous biocompatible materials.) The core 8 having a diameter, dc, about 0.00175 inch, includes a metal, such as tantalum, with a density greater than the longitudinal member 4 to enhance the radiopacity of the filament and thus the stent from which it is formed. The core 8 is bonded to and substantially enclosed by the outer member 4 such that the core does not have any substantial exposed surface and therefore does not contact body tissue when positioned within the body during use. As illustrated, preferably the core 8 is a continuous solid member in intimate contact with and bonded to the interior portions of the outer member 4 without the formation of substantial voids in the interface 10 between the core and outer member. Preferably, the elastic properties of the filament 11 are dominated by the elastic properties of the longitudinal member 4. The core material 8 enhances the radiopacity of the filament 11 but preferably does not substantially affect the mechanical performance of the filament. One aspect of the present invention is that it has been discovered that a stent can be formed of a composite filament exhibiting substantially the elasticity properties of, for example, a solid elastic (used in linear range) or superelastic nitinol filament, (to form, for example, a self-expanding stent), despite the presence of a dense, e.g. tantalum, core, and that the stent formed of the composite filament is more radiopaque than a stent formed of a solid nitinol filament.
[0031]Referring to FIG. 3, the filament 11 is shown in a bent position, as it may be, for example when in use in a knitted stent device. The inner and outer portions (I) and (O), respectively, experience a wide range of compression and tension, as the filament is bent such as during knitting of the stent and during placement of the stent and in use. An advantage of the filament is that by positioning the radiopaque core material 8 near the axis 6, the range of tension and compression imposed on the core is relatively small and a wide latitude of stiff, dense, strong, and/or substantially radiopaque materials can be used which otherwise might not be suitable for their response to bending or other properties.
Parameter Selection
[0032]Generally, the characteristics of the filament and thus the selection of the outer member and core metals, is based on the stent application. Particularly preferred uses of stents of the invention are for the biliary tree (e.g. 8 -12 mm diameter, 2-8 cm length) such as the hepatic and pancreatic duct (e.g. 4-12 mm diameter), the urinary tract including the prostate and urethra (e.g. 14-15 mm, diameter; 3-4 cm, length) and the ureter (e.g. 3-4 mm diameter), and the vasculature including the hepatic vasculature e.g. for the treatment of portal hypertension (e.g. 4-10 mm diameter; 5-6 cm, length), the neurovasculature (e.g. 1 mm, diameter) and the aorta (e.g. 20 mm, diameter) for example, for treatment of aneurysms or lesions. A filament with a larger outer diameter, do, may be used for larger stents. For example, a filament outer diameter, do, in the range of 0.008 inch may be used in the case of an aortic stent.
[0033]Typically, the dimension of the core (dc) is less than about 50% (but typically greater than about 1%) of the outer diameter of the filament, more preferably between about 40% and 25%, for example about 33%. Embodiments of the stent having enhanced radiopacity are especially useful in applications where the stent must be sized small with, for example, a stent wire outer diameter (do) of less than about 0.015 inch, e.g., even less than 0.0075 inch and for which less dense metals are required for advantageous elastic properties. For example, in another embodiment the filament is formed of nitinol with an outer diameter, do, of about 0.006 inch and a core of tantalum with diameter, dc, at about 0.002 inch. Referring to FIGS. 4 to 4b, in embodiments such as that discussed with respect to
[0034]FIGS. 1 and 1a, stent 10 is a self-expanding stent that may be introduced to a body lumen 20 such as the biliary tree. The stent 10 is positioned on a catheter 24 which includes a sleeve 26 to maintain the stent 10 in a relatively compact form (FIG. 4). This is typically achieved by rolling the stent upon itself and a pair of tiny mandrels that nip a portion of the wall of the stent and are rotated bodily together until the full circumference of the stent is taken up in the resulting rolled up form. In other cases, the stent may be positioned coaxially over the catheter. The catheter is positioned within the lumen at the region corresponding to a tumor 22 and the sleeve 26 is removed from about the stent 10, for example, by withdrawing axially in the direction of arrow 28, thus causing the stent 10 to radially expand by release of its internal restoring force (FIG. 4a). The internal restoring force is sufficient to dilate the lumen 20 by pushing the tumor growth 22 radially outward (or in some cases compressing the occlusion against the lumen wall), thus opening a passage that allows unobstructed flow through the lumen and allowing removal of the catheter 24 (FIG. 4b).
[0035]In another embodiment, the stent may be compressed in a tube having a distal axial opening and be pushed from the end of the tube, whereby it self-expands.
[0036]Referring now to FIGS. 5 to 5b, the stent may also be a plastically deformable tube-like knitted structure 50. The individual filament meshes interlock loosely in a looped pattern and during radial expansion of the knitted structure loops forming the individual meshes are deformed beyond the elastic limits of the filament, resulting in plastic deformation of the filament. Stent 50 is placed over a balloon 51 carried near the distal end of a catheter 52. The catheter 52 is directed through a lumen 54, e.g., a blood vessel until the portion carrying the balloon and stent reaches the region of the occlusion 53 (FIG. 5). The stent 50 is then radially expanded beyond its elastic limit by the admission of pressure to the balloon 51 and compressed against the vessel wall with the result that occlusion 53 is compressed, and the vessel wall surrounding it undergoes a radial expansion (FIG. 5a). The pressure is then released from the balloon and the catheter is withdrawn from the vessel (FIG. 5b).
[0037]The stent in the balloon expandable embodiment is preferably formed with a dense radiopaque core formed of tantalum and an outer member formed of plastically deformable stainless steel. While the stent filament is plastically deformable, the filament may be selected to have elasticity sufficient to meet the needs of the particular vessel. In addition, self-expanding stents, such as discussed above with respect to FIG. 4 et seq. can be used with a balloon delivery system to aid dilatation of a body lumen.
[0038]In various embodiments, the metals used in the filament and their configuration are selected to exhibit various desirable characteristics. For example, the relative dimension of the core and outer member and the particular materials used for these elements may be selected based on the desired over-all mechanical properties of the stent and the degree to which x-ray visibility is to be enhanced, since the core affects the mechanical properties of the filament compared to a solid filament formed of the outer material, and the radiopacity is a function of the sum of the mass between an x-ray beam source and detector. A knitted stent with overlapping portions, may require less radiopaque material to provide sufficient visibility. Similarly, the location of use in the body may affect the amount of dense material needed for sufficient visibility. The visibility of a device can be tested by known techniques such as ASTM Designation F640-79 "Standard Test Method for Radiopacity of Plastics for Medical Use". In this test, the background densities which may be encountered clinically are mimicked by an aluminum plate positioned over the stent having various thicknesses.
[0039]The properties of the outer member metal and core which may be considered include density, modulus of elasticity (in annealed and hardened states), biocompatability (primarily a factor for the material of the outer longitudinal member), flexural stiffness, durability, tensile and compression strength, and the required radiopacity and resolution.
[0040]In some cases, if desirable, the inner and outer metals may be the same metal or metals of the same elemental composition that are different metals because of e.g., different crystal structure or other properties.
[0041]In other embodiments of elastic filament members, the outer member is formed of a continuous solid mass of a highly elastic biocompatible metal such as a superelastic or pseudo-elastic metal alloy, for example, a nitinol (e.g., 55% nickel, 45% titanium). Other examples of superelastic materials include, e.g., Silver-Cadmium (Ag--Cd), Gold-Cadmium (Au--Cd), Gold-Copper-Zinc (Au--Cu--Zn), Copper-Aluminum-Nickel (Cu--Al--Ni), Copper-Gold-Zinc (Cu--Au--Zn), Copper-Zinc (Cu--Zn), Copper-Zinc-aluminum (Cu--Zn--Al), Copper-Zinc-Tin (Cu--Zn--Sn), Copper-Zinc-Xenon (Cu--Zn--Xe), Iron Beryllium (Fe3Be), Iron Platinum (Fe3Pt), Indium-Thallium (In--Tl), iron-manganese (Fe--Mn) Nickel-Titanium-Vanadium (Ni--Ti--V), Iron-Nickel-Titanium-Cobalt (Fe--Ni--Ti--Co) and Copper-Tin (Cu--Sn). See Schetsky, L. McDonald, "Shape Memory Alloys", Encyclopedia of Chemical Technology (3rd ed.), John Wiley & Sons, 1982, vol. 20. pp. 726-736 for a full discussion of superelastic alloys. Preferably in some cases of elastic filament members, nitinol or other highly elastic metal is employed as the outer member, in an arrangement in which it is never stressed beyond the straight line portion of its stress strain curve. Other examples of metals suitable for the outer member include stainless steel or the precursor of superelastic alloys. Precursors of superelastic alloys are those alloys which have the same chemical constituents as superelastic alloys, but have not been processed to impart the superelastic property under the conditions of use. Such alloys are further described in co-owned and co-pending U.S. Ser. No. 07/507,375, filed Apr. 10, 1990, by R. Sahatjian (see also PCT application US91/02420) the entire contents of which is hereby incorporated by reference.
[0042]The core material is preferably a continuous solid mass, but may also be in a powder-form. Typically, the core includes a metal that is relatively dense to enhance radiopacity. Preferably, the core metal has a density of about 9.9 g/cc or greater. Most preferably, the core is formed of tantalum (density=16.6 g/cc). Other preferred materials and their density include tungsten (19.3 g/cc), rhenium (21.2 g/cc), bismuth (9.9 g/cc), silver (16.49 g/cc), gold (19.3 g/cc), platinum (21.45 g/cc), and iridium (22.4 g/cc). Typically, the core is somewhat stiffer than the outer member. Preferably, the core metal has a low modulus of elasticity, e.g., preferably below about 550 GPa, e.g., such as tantalum (186 GPa). Generally, a smaller difference between the modulus of elasticity between the outer material and core results in a smaller variation of the modulus from that of the outer material in the filament of the invention. For larger differences, a smaller core may be used so as to produce a filament in which the elastic properties are dominated by the outer material.
[0043]The outer member and core may be in many cross-sectional geometric configurations, such as circular, square, triangular, hexagonal, octagonal, trapezoidal and the geometrical configuration of the core may differ from that of the longitudinal member. For example, the outer member of a filament may be rectangular in cross-section with a rectangular core or triangular or hexagonal in cross-section with a circular core. A stent filament may also take on the form of tubing with a lumen within the core extending along the axis. A stent filament may also include successive layers of less dense outer material and more dense core material to form a multi-composite system of three layers (e.g., layers 4', 9', 8', FIG. 7) or more from exterior to center. The core may extend intermittently along the axis in a desired pattern.
[0044]The filament may be a draw-form member formed, for example, by drilling out the center of a relatively large rod of the outer member material to form a bore, positioning a rod of core material in the bore, sealing the ends of the bore, e.g., by crimping, and drawing the form through a series of dies of decreasing diameter until the desired outer diameter is achieved. The component may be heat treated to anneal, harden or impart superelastic properties. Other methods of formation are also possible, e.g., by coating the core with the desired outer material such as by electro- or electroless plating. The materials used in the outer member and core are also selected based on their workability for forming the filament, including factors such as machinability, for forming the longitudinal member into a tubular piece and the core member into a rod shaped piece, stability in gaseous environments at annealing temperatures, properties related to drawing, welding, forging; swaging, the ability to accept coatings such as adhesives, polymers, lubricants and practical aspects such as cost and availability.
[0045]As evident from the above, the stents of the invention are preferably constructed by knitting a filament, most preferably on a circular knitting machine. Knitted metal stents are discussed, for example, in Strecker, U.S. Pat. No. 4,922,905. It will be appreciated that the stent may be formed from a composite metal filament by other means such as weaving, crocheting, or forming the filament into a spiral-spring form element. It will further be appreciated that the composite filament may be incorporated within a stent formed from conventional metal or non-metal materials (e.g. dacron in the case of an aortic graft) to contribute desirable properties such as strength and/or radiopacity. The stent may also be in the form of a metal member configured as other than a filament-form, e.g., a composite sheet form member in the form of a cuff or tube.
[0046]The following example is illustrative of a stent filament.
[0047]An elastic, radiopaque filament for use in a stent may be formed as follows. A 500 foot length of filament (0.0052 inch in diameter) having an outer member formed of a precursor of a nitinol (55% Ni/45% Ti) superelastic alloy and a core material of tantalum (0.00175 inch in diameter) is formed by drilling a 0.25 inch diameter bore in a 0.75 inch rod of the outer member material and providing in the drilled lumen a tantalum member of substantially matched outer diameter. The rod is mechanically forged in a standard hot forging and rolling apparatus, then hammered such that no substantial voids between the core and outer longitudinal member are present. One end of the rod is sealed and the opposite end is cold drawn longitudinally through a die to the final diameter. Initially, the outer member of the filament is the precursor of a superelastic alloy, i.e., it has not been heat treated to impart the superelastic property under the anticipated conditions of use.
[0048]Referring to FIG. 6, load versus displacement curves are illustrated. (For clarity, curves C, D and A are offset, successively, 0.025 inch on the x-axis.) Curve A illustrates the filament as discussed in the above paragraph prior to heat annealing which induces the superelastic property; the filament exhibits substantially linear elastic strain as a function of stress to a break point z. Curves B, C, D illustrate stress/strain curves after annealing the filament at 460° C. for 3 minutes, 5 minutes and 15 minutes, respectively. As these curves illustrate, the superelastic nature of the filament is substantially preserved, as evidenced by the substantial plateaus (p) on the stress/strain curve, despite the presence of the tantalum core. Also as illustrated, the stress at which constant displacement occurs decreases with increasing annealing, as would be expected with a superelastic material. The mechanical properties of the filament, therefore, are dominated by the nitinol alloy, despite the presence of the tantalum core.
[0049]Referring to Table I, the modulus of elasticity and plateau stress calculated based on stress-strain measurements as above, are compared for the filaments of the invention and a solid filament of Ni--Ti alloy.
TABLE-US-00001 TABLE I % Charge in Ni--Ti Ta Cored Ni--Ti Cored Filament Diameter .0038'' .0052'' -- Area 1.134 × 10-5 in2 2.124 × 10-5 in2 -- (Modulus of Elasticity Precursor 5,401,300 psi 7,373,865 psi +27% 460° @ 3 mins 6,967,150 psi 6,657,00 psi -4.5% 460° @ 5 mins 5,381,160 psi 5,721,100 psi +6.0% 460° @ 10 mins 5,139,310 psi -- -- 460° @ 15 mins 5,143,960 psi 5,551,924 +7.4% Plateau Stress (loading) 460° @ 3 mins 101,400 psi 97,174 -7.2% 460° @ 5 mins 89,056 psi 84,757 -4.8% 460° @ 10 mins 79,357 psi -- -- 460° @ 15 mins 72,303 psi 75,339 psi +4.1%
[0050]As the results in Table I illustrate, the modulus of elasticity of the filaments of the invention was varied less than 30% compared to the solid Ni--Ti filament. The plateau stress of the filaments of the invention using a superelastic outer member was varied less than about 10% compared to a solid Ni--Ti superelastic filament. The composite filament formed as described exhibits about 30% or more enhanced x-ray visibility over a filament of the same thickness formed of solid nitinol.
[0051]It will be understood that such filaments may be employed both in instances where the superelastic property is employed, and in instances where it is not (all stress within the straight line portion of the stress strain curve).
[0052]The visibility of a knitted stent formed from the filament was greater than a comparison stent using a solid nitinol filament of larger (0.006 inch) diameter, yet using the stent of the invention, the force needed for radial compression of the stent was reduced compared to the stent formed of the thicker nitinol filament. Thus, radiopacity of the stent was enhanced while mechanical properties were dominated by the outer member, nitinol. Placement of the stent, as-described above, can be monitored by x-ray fluoroscopy.
[0053]Preferably, filaments as described, dominated by the mechanical properties of an outer member, such as nitinol, and exhibiting generally satisfactory radiopacity have outer diameter (do) of about 0.008 to 0.0045 inch with a core, for example of tantalum, with diameter (dc) of about 0.0014 to 0.00195 inch.
[0054]Other embodiments are in the following claims.
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- Description
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Casino series is Bling My Things newest design for iPhone 6/6s / 6 Plus collections. It consists of Bowtie Crystals from Swarovski® and 3 round crystals, resembling buttons. It comes directly under the Apple logo and it looks super sleek and chic! Ultra-clear, durable polycarbonate casing protects your iPhone while adding glamour. Fits any iPhone body colors.
• Case color: clear
• Case: anti-scratch finish
• Swarovski® Crystals: Light Siam and Crystal
• Individual crystal setting for every crystal ensuring excellent hold
• Designed for iPhone 6/6s (this products does not include iPhone 6/6s)


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I'm freaking over a new measure that will drastically affect all those cute toymaking people at Etsy or in your local craft fair. See my latest bloglet post:
I just learned that on account of a stringent new safety measure passed by the new Consumer Product Safety Improvement Act (CPSIA), our toy-making friends at Etsy and anyone else who makes fantabulous handmade objects of delight for children may soon be history.
The measure is designed to protect us from the freaky stuff in mass-produced toys, after the recalls on Chinese-made products got the nation into a tizzy over safety.
Like any parent with a titch of common sense, I'm all for the banning of lead and those other un-spellable dangerous compounds. I'm all for asking corporations to show us that their mass-produced toys are safe. But the CPSIA Act mandates that smaller handmade, artisanal-type businesses in Europe, Canada, and the US also roll out new tests and comply with an expensive new regulatory process that will drive most of them out of business.
And for what? It all seems a touch absurd, since we haven't had any problems with Waldorf dolls from Wisconsin, Pinocchio puppets from Prague, or wooden teethers from Winnipeg.
Please go here to read the complete story and add your two cents if you so desire. Seriously, I am so over all this safety hysteria in parenting. I just saw on a mommy noticeboard some dufus mother was worried that a Christmas poinsettia would pose a danger to her infant.
Yes, a Christmas poinsettia is going to kill your tot!
I mean, hey. Maybe she has a point. Maybe we need to get some legislation on Christmas vegetation. What if an infant gummed your wreath before you put it up and got a pine cone lodged in his throat! And maybe we need to extend this legislation to include food baskets. After all, it is entirely possible that your toddler could shove a Harry and David cashew up her nostril.
Shall we take action? Want to join me? Shall we write to Obama and ask him to add poinsettias and Christmas cashews to his list of national threats? LET'S!


text:
Chris Ballard delves into the depths of the NBA game with "The Art of a Beautiful Game." I truly enjoyed this book; I couldn't put it down until I finished it.
Although the subtitle is The Thinking Fan's Tour of the NBA, it's really more for observant NBA fans and true fans of basketball in general. It doesn't necessarily challenge you to think about the impact of basketball or how it ties into society.
Ballard focuses on different aspects of the sport, tying anecdotes around an NBA star who most exemplifies this characteristic. For example, the chapter on defensive prowess focuses on Shane Battier or the chapter on shooting focuses on a 3-point contest the author had with Steve Kerr.
Even if you're just a casual fan, the small tidbits of information Ballard drops will keep you coming back for more. Want to know how Pittsburgh's Sam Young prepared for the NBA Draft? Who is Idan Ravin and why does Carmelo Anthony respect him so much?
Ballard even drag-races Shaquille O'Neal after leaving the Suns locker room. After reading "The Art of a Beautiful Game," you're challenged to watch an NBA play closely and this book will definitely equip and reward you.


text:
Deadly highway: 7 fatalities prompt billboard warning
The billboard may not win a Clio. But all Albemarle County Police really want is to stop the carnage on U.S. 29 south of Charlottesville.
Unlike its more heavily traveled counterpart north of town, the southern Monacan Trail end of U.S. 29 is usually a pretty easy, uncongested drive. So when the 2009 death toll between I-64 and the Nelson County line reached seven by October, Albemarle County Police looked for a way to slam the brakes on those grim statistics.
"It's a disturbing trend," says Lieutenant Todd Hopwood, who noted December 17 that there were no fatalities on 29 South the previous four years. Yet during the last week of October, two accidents took three lives in a couple days, and within a quarter-mile of each other. One was activist farmer Kathryn Russell, who was struck crossing 29 at Plank Road October 22 and thrown from her truck.
Why the sudden spate of deaths? Police found two things in common: five of the seven were not wearing seatbelts, and five were from out of town.
In a multi-agency effort, Albemarle police have stepped up patrols and added rumble strips and a radar-equipped, your-speed-is sign.
AAA of the Mid-Atlantic sprang for the $1,500 billboard near Crossroads Store that warns of the strict enforcement. The billboard went up December 7 for the holidays and will go up again in the spring, says AAA's Windy VanCuren.
The buckle-up warnings have been repeated a million times before, but with seven deaths in a short stretch of road and short period of time, VanCuren hopes the message sinks in: "Most of these could have been avoided."
10 comments
29 S isn't that bad. If people wouldn't drive like idiots (excess speed, weaving, not paying attention to the surroundings, stupid stuff like that) there wouldn't be as many issues. You don't need to be going 65 MPH down that road.
Who doesn't wear a seatbelt these days?
and while that billboard has my attention i slam into a deer!
I have a problem if you dont want to wear your seat belt then it is on you why is the police so worry about you that just give them reasons to pull people over!!!!! I known people that had seat belts on and still died so what is ya'll point dont have nothing better to do but harrass people Virginia please follow ya'll own law n stop trying to make up new ones all the time
Too many hills, blind curves, and uncontrolled access coupled with heavy truck traffic are a recipe for disaster. VDOT needs to bring this stretch of highway up to at least 1975 standards. They managed to build a nice safe road around Lynchburg, why not around Charlottesville? VDOT has put in some mighty nice roads for other cities like Lynchburg, Blacksburg/Christiansburg, & Roanoke, but they have refused to do anything up here for decades. Where is the outcry? Where are they spending our share of the transportation budget?
The problem is people driving like a bunch of idiots. Anybody who can't drive 45 to 55 mph on 29 South without running off the road or runing into somebody else has no business with a driver's license in the first place.
Comment deleted by administrator 2pm December 22.
The state just needs to reduce the speed limit. There is no need to litter our roads with blinking lights, distracting signs, speed bumps,and other driver distractions. There is also no need to be going 65 down 29 through Albemarle County. Just reduce the speed limit. The curves and hills make it difficult for those crossing 29. If there was just more time from the point a crossing vehicle identifies a clear passage, the crossing vehicle would be safer. The way it is now, you see a clear passage, start on the gas, and HELLO, someone comes flying up the hill and nearly hits you. But it's ok(sarcasm), because the speed limit is 60 (which means they can go 65), and if you are smart and wear a seatbelt, you may actually survive the collision. Please, VDOT, just reduce the speed limit.
yeah grammar lady!!
That's a lot of lives lost. Why is it the fault of no seatbelts? I think they need to look at the intersections and the design of the road. There is evidentally a problem there. The deaths by no seatbelts were the symptom, not the problem.


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"An annotated bibliography includes a summary and/or evaluation of each of the sources. Depending on your project or the assignment, your annotations may do one or more of the following:
Summarize: Some annotations merely summarize the source. What are the main arguments? What is the point of this book or article? What topics are covered? If someone asked what this article/book is about, what would you say? The length of your annotations will determine how detailed your summary is.
Assess: After summarizing a source, it may be helpful to evaluate it. Is it a useful source? How does it compare with other sources in your bibliography? Is the information reliable? Is this source biased or objective? What is the goal of this source?
Reflect: Once you've summarized and assessed a source, you need to ask how it fits into your research. Was this source helpful to you? How does it help you shape your argument? How can you use this source in your research project? Has it changed how you think about your topic?
Your annotated bibliography may include some of these, all of these, or even others. If you're doing this for a class, you should get specific guidelines from your instructor."
FromPurdue Owl http://owl.english.purdue.edu/owl/resource/614/01/
1. Bibliography according to the appropriate citation style (MLA, APA, CBE/CSE, etc.).
2. Explanation of main points and/or purpose of the work—basically, its thesis—which shows among other things that you have read and thoroughly understand the source.
3. Verification or critique of the authority or qualifications of the author.
4. Comments on the worth, effectiveness, and usefulness of the work in terms of both the topic being researched and/or your own research project.
5. The point of view or perspective from which the work was written. For instance, you may note whether the author seemed to have particular biases or was trying to reach a particular audience.
6. Relevant links to other work done in the area, like related sources, possibly including a comparison with some of those already on your list. You may want to establish connections to other aspects of the same argument or opposing views.
The first four elements above are usually a necessary part of the annotated bibliography. Points 5 and 6 may involve a little more analysis of the source, but you may include them in other kinds of annotations besides evaluative ones. Depending on the type of annotation you use, which this handout will address in the next section, there may be additional kinds of information that you will need to include.
Types of annotations
One annotation does not fit all purposes! There are different kinds of annotations, depending on what might be most important for your reader to learn about a source. Your assignments will usually make it clear which citation format you need to use, but they may not always specify which type of annotation to employ. In that case, you'll either need to pick your instructor's brain a little to see what s/he wants or use clue words from the assignment itself to make a decision.
Summary annotations
There are two kinds of summarizing annotations, informative and indicative.
Summarizing annotations in general have a couple of defining features: They sum up the content of the source, as a book report might. They give an overview of the arguments and proofs/evidence addressed in the work and note the resulting conclusion.
They do not judge the work they are discussing. Leave that to the critical/evaluative annotations.
Informative annotation
Informative annotations sometimes read like straight summaries of the source material, but they often spend a little more time summarizing relevant information about the author or the work itself.
Indicative annotation
Indicative annotation is the second type of summary annotation, but it does not attempt to include actual information from the argument itself. Instead, it gives general information about what kinds of questions or issues are addressed by the work. This sometimes includes the use of chapter titles.
Evaluative annotations don't just summarize. In addition to tackling the points addressed in summary annotations,
evaluative annotations:
evaluate the source or author critically (biases, lack of evidence, objective, etc.). show how the work may or may not be useful for a particular field of study or audience. explain how researching this material assisted your own project.
An annotated bibliography may combine elements of all the types. In fact, most of them fall into this category: a little summarizing and describing, a little evaluation.
From: The Writing Center, University of North Carolina at Chapel Hill http://writingcenter.unc.edu/resources/handouts-demos/specific-writing-assignments/annotated-bibliographies


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DYNAMICALLY RECONFIGURABLE ON- AND OFF-CHIP NETWORKS by Bilal Zafar A Dissertation Presented to the FACULTY OF THE USC GRADUATE SCHOOL UNIVERSITY OF SOUTHERN CALIFORNIA In Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY (COMPUTER ENGINEERING) May 2011 Copyright 2011 Bilal Zafar
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|Dynamically reconfigurable off- and on-chip networks
|Zafar, Bilal
|Author email
|firstname.lastname@example.com; firstname.lastname@example.com
|Doctor of Philosophy
|Document type
|Degree program
|Computer Engineering
|Viterbi School of Engineering
|Date defended/completed
|Date submitted
|Restricted until
|Date published
|Advisor (committee chair)
|Draper, Jeffrey T.
|Advisor (committee member)
Prasanna, Viktor K.
Nakano, Aiichiro
|Computing systems are increasingly becoming communication bound. From mega-watt servers in data centers to mobile and embedded systems, the cost, performance and reliability of the communication fabric has rapidly become a first-order design concern in digital systems at every scale. At the same time, traditional solutions to connecting resources are fast approaching their natural limits beyond which they will not be able to offer the requisite performance at acceptable area, power or dollars cost.; The growing need for a low-latency, high-bandwidth interconnect fabric for cluster systems has made InfiniBand Architecture (IBA)-compliant devices the fabric of choice in high-performance systems. IBA is an open, industry-standard specification that is designed specifically for high performance, quality of service guarantees and high robustness. For high robustness, availability and dependability, IBA-compliant networks must be able to adapt to changes in the topology caused by, for example, hot-swapping of components or faults in the network, without negatively impacting the end-to-end latency of application traffic. In this work, we present a mechanism for InfiniBand networks to reconfigure the routing algorithm without stopping injection of packets, discarding routable packets already in the network or significantly reducing the available bandwidth. The proposed mechanism uses a deadlock-free dynamic reconfiguration scheme called the Double Scheme and features available in IBA to seamlessly update the active routing function in seven steps with very little overhead. Simulation results show that using the proposed mechanism InfiniBand network remain available for application traffic during the entire reconfiguration process. This availability in the presence of failure comes at the cost of only a slight increase in the reconfiguration time.; Challenges facing traditional interconnects are not limited to off-chip interconnect fabric like InfiniBand networks. Point-to-point wires, fully-connected crossbars and shared busses which have been used as communication fabrics in multi-core processors also face a myriad of challenges like scalability, power dissipation and wiring complexity. Packet-switched on-chip interconnection networks have been proposed as a solution and this work prunes the design space of topologies for these on-chip interconnection networks using relevant quantitative and qualitative metrics. Our analysis shows that 2D mesh, torus and hierarchical ring topologies meet most of the requirements for interconnects in moderate-sized many-core CMPs.; As the number of cores per die grows, power dissipation in the on-chip interconnection network will increasingly becoming a key barrier to scalability. Studies have shown that on-chip networks can consume up to 36% of the total chip power, while analysis of network traffic reveals that for extended periods of execution time, network load is well below the network capacity in many applications. We analyze seven representative parallel applications to quantify the temporal variability in the bandwidth demand of typical applications. Analysis shows that in most of the characterized applications the demand for network bandwidth varies across applications as well as over time during the execution of the same application. In five of the seven analyzed applications, the bandwidth demand is close to zero for over 90% of the execution time. More importantly, the off periods are 1ms or longer, which means that there is a significant opportunity to turn network resource on and off based on the temporal variations in the bandwidth demand of the application.
|computer architecture; on-chip networks; Infiniband; network-on-chip; interconnection networks; reconfiguration; power-aware networks; power-gating; voltage island
|Part of collection
|University of Southern California dissertations and theses
|Publisher (of the original version)
|University of Southern California
|Place of publication (of the original version)
|Los Angeles, California
|Publisher (of the digital version)
|University of Southern California. Libraries
|Electronically uploaded by the author
|Legacy record ID
|Contributing entity
|University of Southern California
|Zafar, Bilal
|Repository name
|Libraries, University of Southern California
|Repository address
|Los Angeles, California
|Repository email
|Archival file
|Page 1
|Contributing entity
|University of Southern California
|Repository email
|Full text
|DYNAMICALLY RECONFIGURABLE ON- AND OFF-CHIP NETWORKS by Bilal Zafar A Dissertation Presented to the FACULTY OF THE USC GRADUATE SCHOOL UNIVERSITY OF SOUTHERN CALIFORNIA In Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY (COMPUTER ENGINEERING) May 2011 Copyright 2011 Bilal Zafar


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After replay, Rockies just miss turning triple play
DENVER -- The Rockies came within mere inches of their second triple play of the season during the top of the fifth inning Friday night against the Pirates at Coors Field, but instant replay upheld a call by umpire Tom Hallion that an out was not recorded at second base.
The Rockies led, 1-0, at the time.
With runners at first and second, the Pirates' Jordy Mercer grounded a Brett Anderson pitch hard to third baseman Charlie Culberson, who made a couple quick strides to the bag to force out Neil Walker. Culberson fired to shortstop Josh Rutledge, who covered second because the infield was shifted to the right side. Rutledge's throw to first beat Mercer.
However, Hallion ruled that Rutledge was off the bag at second when he received the throw from Culberson, so Russell Martin was called safe.
Rockies manager Walt Weiss challenged the call, but the replay determined that the call would stand. The ruling left him 11-for-26 on challenges this season.
The Rockies turned an around-the-horn triple play on May 18, with the help of a correct umpire call. The Padres' Seth Smith was ruled to have interfered with LeMahieu when he slid well inside the bag, reached across his body and hooked LeMahieu's foot with his hand.


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Get ready for Playboy's Girls of the ACC
Playboy's Girls of ACC issue hits stands Friday, September 11, featuring one UVA lovely who'll be known in their pages as Jenna Arianna (her first and middle names). The last UVA co-ed picked for the honor– Amanda Paige– went on to become the mag's Playmate of the Month in October 2005 and appeared on a cover in 2007. While Paige and the two other UVA students who appeared in the magazine in fall 2004 autographed copies of their issue during an event on the Corner, no such events are planned in Charlottesville this time around, according to a Playboy spokesperson.
Read more on: amanda paige gellarplayboy


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Compute the charge density distribution and potential variation inside a MOS structure by using a coarse-grained tight binding model
Version 1.0a - published on 26 Feb 2015
doi:10.4231/D3GX44V81 cite this
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CGTB is an interactive tool for computing the charge density distribution and potential variation inside a MOS structure. A full tight binding description of the silicon atoms is coarse-grained to a 1-D tight binding description by using the periodicity of the electronic properties in the planes parallel to the dielectric layer. In the CGTB rapture tool, the user can specify the applied potential on the metal layer and the gap of between the silicon structure and the metal layer (i.e., the thickness of the dielectric layer). The charge density and potential profiles in the MOS structure are computed and plotted.
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text:
It's no secret that I have mixed feelings abut the past. On one hand I love thinking back and seeing how the past has shaped who I am. On the other hand I am so so glad to be away from a lot of it and I try and focus forward as much as possible.
Anyway a bit of a L. M. Montgomery obsession when I was younger inspired me (I think it was from the Emily series but I could be wrong) to write letters every birthday to myself, to be opened 10 years later.
I put them in a box and put the box on a bookshelf and pretty much completely forgot about them except every few years when I'd stumble across it and read through the letters I'd missed. Which I did again yesterday.
Mostly they're actually a bit disappointing. I learned that my handwriting and general language has improved, that my aims and ambitions in life are vastly different to what they were in early adolescence and that what seemed important at the time is much less important now. And I learned that I was a really angry teenager.
Oddly enough three of them really stood out: one from my 15-year-old self where in barely legible handwriting it says "You'd better be happy, if I have to survive adolescence for you you'd better enjoy adulthood for me!" Another that I wrote when I started my PhD to check on general progress and re-motivate (I was quite the pep-talker at 21) and one that I wrote while I was still an undergrad at university.
I think I wrote it having realised that my teenage self had very little of value to say and so I wrote a letter for five years later before I stopped writing them altogether. I read it this morning (a year later than it was intended for but moving on) and I found it quite entertaining, so I thought I would share. It makes me cringe a little bit, but it makes me smile more.
It's so hard to write to someone I know so little about. Four and a half years is a long time. I just read the letter I wrote when I was 14 to be opened when I was 18. It sounds so exuberant, expecting great things. It scares me that I may have lost that.
I want to change the world, to really make a difference. This world isn't what it's meant to be. I want a job I love. i feel like I MAY have found it here, I know for the first time ever my holidays have a countdown to going back (37 days and counting, for the record).
this is your life, are you who you want to be?
Anyway I'm writing this partly as a reminder – I want you to sit and think: is what you're doing good enough? Is it REALLY what you wanted all along? Do you wake up in the morning morning excited to go to work? Is it the first thing you think about in the morning and the last at night? Do you discuss it over cappuccinos (and PLEASE tell me you still clean your spoon first!).
If this is not the case get out. Leave. Quit. You'd be better off selling dogfood again, even busking or selling mangoes at the side of the road like mom used to threaten. Don't get trapped where you aren't happy.
Are you who you want to be?
Now for the fun stuff!
Last 10 messages on my phone:
1-4 whining from ______ Did she EVER stop? It's not that these things only happen to her, it's that other people shut up about it. And saying 'oh poo!' and 'vomit' I mean REALLY. Grow up!
5. S telling me I forgot E's birthday. oops.
6, 7. _______ ditto
8. Brother's girlfriend organising a church thing.
9. ________ ditto
10. CR, organising new years photos
Cards in my wallet: drivers license, movie card, bank card, Mugg & Bean card, student card, Scuba Diver and Advanced diver card, Exclusive books card, Videostore card, Gym card, Organ Donor card, Blood donor card
Last movie: Oceans 12, ________ whined the whole way through.
Currently reading: Garden of Beasts by Jeffrey Deaver
Number of 'what are you doing with your life?' talks this week? Once so far but it's still Sunday…
Anyway that's about it. I'd ask questions but that's a bit stupid considering you can't answer them unless technology REALLY improves in the next few years. Which I doubt.
I hope you're still diving and you still love the sea.
Did you ever get a chance to go in a submersible? I think that's so amazing! I want to do mid-oceanic ridge biology research someday. Just a thought. Don't tell mom.
Keep being more than just fine!
P.S. Your drivers license is about to expire, and I'd check my passport and ID if I were you..
So that was me at 19. Even then I appreciated that I'd probably forget to renew my passport…
*from the new She & Him album. Isn't it awesome when the song stuck in your head fits in with life in general?


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Amanda Clayton was not your typical millionaire. In her short life, she won a million dollar lottery in Michigan, was convicted of collecting state welfare money AFTER she got the million dollars and embroiled in a plethora of drama and legal battles.
Now she is dead, at age 25, of a drug overdose.
I've devoted much of my life to studying why people run through large sums of money. Especially lottery winners. I've written two best-selling books, along with a new book, "Life Lessons From the Lottery,†which will be out on Kindle on Nov. 10.
And they all focus on why people run through money needlessly.
I keep thinking that if Amanda had read one of them, she might be alive, but probably not. She lived a troubled life. Getting the lottery money added rocket fuel to her problems.
Like so many lottery losers, Amanda made the first big mistake when she won the lottery: She let the world know she won.
In her home state of Michigan, it's possible for state lottery winners to collect their winnings anonymously, except for Mega Millions and Powerball winners.
Thus, Amanda would have been better off to quietly take her winnings, but it didn't work out that way.
If you go online, you can find a happy and attractive Amanda from September of last year. She was smiling, holding a huge million dollar check from the Michigan Lottery.
Now she is in a coffin, holding a lily. For eternity. To me, the big check and lily are correlated.
Telling the world that you have money that you never expected to have is asking for trouble. Like Abraham Shakespeare, another lottery winner who wound up dead in Florida, people thinking that your money should be "our†money seem to come out of the woodwork.
From various news accounts, it seemed like Amanda had a ton of newfound "friends.†All wanting to take advantage of her.
Although Amanda was not shy about making headlines with her check, there was one group of people she "forgot†to mention it to.
The food stamp and public assistance office.
According to the Detroit News, Clayton plead no contest to fraud in June after state prosecutors accused her of receiving $5,500 in food and medical benefits after she won the lottery.
Millionaires are not supposed to collect food stamps. If Amanda had tried to rip off the government as a Wall Street banker, her crime would been ignored and she probably would have received a government bailout.
She got nine months probation instead. She wound up not staying alive until the end of her sentence.
It's sad to see a 25-year-old throw her life away. I'm not sure that winning the lottery was the source of her problems, but I see it happen too many times.
People who win the lottery lose perspective on the normal things in life. They start to think that rules don't apply to them. In Amanda's case, she thought she could outsmart the welfare people and do serious drugs without consequence.
She lost her bet both times.
It's been said that roughly 90 percent of people who win the lottery will run through it in five years or less. I tell lottery winners to do five things to protect themselves.
1. Don't tell anyone you won. If you can collect the money anonymously, do so.
2. Stop and think for a minute before rushing down to collect the check.
3. Don't take the lump sum payment. Take the money over time instead.
4. Find an advisor who has worked with more money than what you have. If you win $100 million, find an advisor who has clients with $150 million. They are out there.
5. Use your money to give something back to society.
It looks like Amanda went five for five in things that she did wrong.
Now she is no longer with us.
Don McNay, who lives in Richmond, Ky., is an award-winning financial columnist for Huffington Post Contributor. You can learn more about him at www.donmcnay.com.


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