text:
by Amy Crandall
Genre: YA Psychological Thrille
As she waits to give her statement in one of the interrogation rooms of Arcata Police Department, Abigale recites the same line over and over inside her head.
I did not kill anyone.
I did not kill anyone.
But there's a trail of bodies, and it leads straight to her. The events that brought her to this very moment all point to one thing…her guilt.
She must convince Detective Collins of her innocence, but how can she explain her ties to the victims, and the evidence that has her name written all over it?
Then there's the mysterious Facebook profile. DarkHeart434.
Who is DarkHeart434? And why does it seem like this person has all the answers, including the identity of the real murderer?
As pieces of the puzzle start to come together, everything about Abigale's life begins to unravel—her past, her present…and even her self-proclaimed innocence.
Amy Crandall is an avid reader and novelist born and raised in British Columbia, Canada. She began writing in elementary school, publishing
her first story on Wattpad.com at the age of thirteen. With the support of her loved ones and newfound friends on the site, Amy continued to share her thoughts and interests in the form of
Before her Wattpad.com days, she was published in A Celebration of Poets -
Summer 2012 (Creative Communication, 2012) for her poem My Garden.
That experience only drove her desire to further pursue writing. Her first full-length novel, "Delusions", was a featured story on Wattpad.com, reaching #7 in the mystery/thriller genre, and surpassing 115,000 reads, before its publishing.
When she isn't envisioning a new story plot, Amy can be found camping with loved ones, getting lost in a great read, jamming to her favourite tunes, or giving in to her craving of Timmies' iced lemonades.
Follow the tour HERE
for exclusive excerpts, guest posts and a giveaway!
for exclusive excerpts, guest posts and a giveaway!


text:
Restaurant Hood Cleaning Bartonville - Clean a Commercial Range Hood
Hood Cleaning Contractors in Denton County, Texas.
Jasvid Hood Cleaning is proud to be recognized as the Best of Bartonville Hood Cleaning Contractor! Choose what services you are interested, and read below the tremendous benefits of the best hood cleaning money can buy.
We are 100% committed to your satisfaction, so you know we will never skip over any detail or cut any corners during your project. All you have to do is request a quote, get on our schedule, and experience the spray foam difference! It really is that simple.
We Also offer
Why Choose Jasvid Hood Cleaning?
To inspect your hood system, begin with the motor compartment. If your kitchen is hot or has visible smoke, then this compartment has probably malfunctioned. Next, inspect the motor's belt, ensuring the straps are not cracked, loose, or slipping.
Visible smoke is often caused by a broken belt, which prevents your exhaust fan from functioning correctly. If this is the case, contact Jasvid Hood Cleaning for prompt, reliable solutions and services.
There are several reasons behind your hood leaking grease. Your fan could be turning too quickly, or a temperature rise could be causing the built-up grease to break off.
Sometimes, the leaking grease could be from the vibrations of an overworked motor, causing the grease to dislodge and fall.
Though there are many causes of a loud fan, natural wear and tear is one of the most common causes. The more the grease builds up, the more overworked and stressed the motor becomes. When the engine operates at maximum capacity, it creates more noise than the sound-reducing elements can effectively handle.
Clean the area around your exhaust system and remove any food items from the area. This will help us prevent contamination while we maintain your exhaust fan.
Since each ventilation system is different, the time the service takes will vary. However, routine kitchen exhaust maintenance usually takes about three hours on average.
At Jasvid Hood Cleaning, we stand behind the quality of our workmanship. Backed by a team of experienced and well-trained professionals, we assure all our customers that our maintenance and kitchen exhaust cleaning services will meet your expectations.
Jasvid Hood Cleaning is fully insured, licensed, and bonded to conduct kitchen exhaust maintenance services. While safety is a priority, we understand that accidents can happen. However, you can rest assured that, if they do, you will not be liable for the injuries or damages.
The frequency of grease trap cleanings depends mainly on the kitchen's fats, oils, and grease capacity or FOGs. For the most part, you should clean them every one to three months.
When your drainage begins to slow down or continuously backs up, this can signify that your grease trap is full or needs cleaning. You can also tell by performing a visual inspection.
The recommended grease trap size depends on the rate of incoming flow from your plumbing system. For instance, if your plumbing system is rated at 30 gallons per minute (GPM), then you should buy a grease trap with twice the capacity, or 60 GPM.
The components of grease traps and interceptors generally work the same way. The only difference between them stems from their capacity. However, a grease interceptor is better suited for kitchens with a flow rate of over 50 GPM, while grease traps handle-less GPM.
Depending on the amount of traffic or buildup your site sees, you can schedule pressure washing services as needed. Some buildings may need a touchup every couple of months, while others only once per year.
You can use pressure washing to clean many different hard surfaces surrounding your business or home. These surfaces include parking lots, sidewalks, dumpster pads, drive-thrus, siding, fences, entrances, and more.
Pressure washing and power washing are two terms often used interchangeably. They both involve using pressurized water to blast away stuck-on dirt and grime. However, the key difference between them is that power washing uses heated water and pressure washing does not.

subset: commoncrawl


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The New York Public Library, Columbia University and New York University Forge Historic Collaboration
The collaboration, dubbed the Manhattan Research Library Initiative, or MaRLI, will help the institutions increase access to research collections, increase use of specialized collections, and stretch collection dollars for covering research resources.
The institutions will coordinate their research collecting, eliminating overlap of specialized materials and identifying opportunities for shared collecting. They will be able to do so by making their collections mutually available to researchers.
"I am delighted that we have been able to spark this new collaboration, which is unprecedented among these three great research institutions," said New York Public Library President Paul LeClerc. "We are creating opportunities to get more use of the existing collections, save resources in areas of overlap, and improve services to users who need our research collections. This project has the potential to positively impact their resulting work and change the landscape of scholarship."
MaRLI will enable NYU and Columbia PhD students and faculty, as well as scholars whose work is based at NYPL, to check out materials from all three libraries, a first step to improve access to collections among the three institutions. The model is a departure from NYPL's historical practice, whereby research materials have not been allowed to circulate.
New York Public Library users unaffiliated with NYU or CU can obtain borrowing privileges by demonstrating that they have exhausted the available resources for their projects and need sustained access to the resources of the three institutions. A research consultation with an NYPL librarian and a completed form are required.
"Reciprocal access is a significant advance for scholars at our institutions, especially in the humanities and social sciences," said James G. Neal, Vice President for Information Services and University Librarian, Columbia University. "The fact that a Columbia faculty member or PhD student will be able to check out a book from the research collections at NYPL or NYU and leave the building with it sounds mundane, but it is a huge step forward for scholars working in Manhattan."
"It makes sense to leverage both technology and our proximity in order to cooperate at a heightened level," said Carol A. Mandel, Dean of the NYU Division of Libraries. "There is so much content that our scholars need. With MaRLI, our combined collecting power will enable us to create collections more wisely and make more content available to more people. Our shared collection will be a research resource greater even than the sum of its parts."
The three world class research institutions already participate in many resource-sharing library networks, notably the SHARES international network of research libraries. The New York Public Library has long participated in the IDS Project, a cooperative within New York State whose members include public and private academic libraries and the New York State Library. Columbia participates in Borrow Direct, a collaboration among the Ivy League universities and MIT. NYU shares research collections and services with The New School and Cooper Union through the Research Library Association of South Manhattan. There are many other examples; the establishment of MaRLI thus builds on a strong platform of inter-institutional collaboration. In future, MaRLI may include delivery of materials among the three libraries. For now, users will check out materials at each site.
Columbia University Libraries/Information Services
Columbia University Libraries/Information Services is one of the top five academic research library systems in North America. The collections include over 11 million volumes, over 150,000 journals and serials, as well as extensive electronic resources, manuscripts, rare books, microforms, maps, graphic and audio-visual materials. The services and collections are organized into 22 libraries and various academic technology centers. The Libraries employs more than 550 professional and support staff. The website of the Libraries is the gateway to its services and resources: https://library.columbia.edu
New York Public Library
The New York Public Library was created in 1895 with the consolidation of the private libraries of John Jacob Astor and James Lenox with the Samuel Jones Tilden Trust. The Library provides free and open access to its physical and electronic collections and information, as well as to its services. Its renowned research collections are located in the Stephen A. Schwarzman Building at Fifth Avenue and 42nd Street; The New York Public Library for the Performing Arts at Lincoln Center; the Schomburg Center for Research in Black Culture in Harlem; and the Science, Industry and Business Library at 34th Street and Madison Avenue. Eighty-eight branch libraries provide access to circulating collections and a wide range of other services in neighborhoods throughout the Bronx, Manhattan, and Staten Island. Research and circulating collections combined total more than 50 million items. In addition, each year the Library presents thousands of exhibitions and public programs, which include classes in technology, literacy, and English for speakers of other languages. All in all The New York Public Library serves more than 17 million patrons who come through its doors annually and millions more around the globe who use its resources at www.nypl.org.
NYU Division of Libraries
The NYU Division of Libraries is a six-library, 4.1 million-volume system. Its flagship, the Elmer Holmes Bobst Library on Washington Square, houses 3.9 million volumes, audio-video resources, and archives and special collections, and provides access to thousands of electronic resources both on-site and online. The NYU Division of Libraries also includes the following five specialized libraries: NYU Abu Dhabi Library, Institute of Fine Arts Library, Courant Institute of Mathematical Sciences Library, Jack Brause Library at SCPS Midtown, and the Library of the Institute for the Study of the Ancient World. Other NYU libraries include the Frederick L. Ehrman Medical Library, the John and Bertha E. Waldmann Memorial Dental Library, and the Law Library. The Libraries website is http://library.nyu.edu/


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Chapter Reveal + Giveaway: Seed by Cassia Leo
Today we have the chapter reveal for SEED by Cassia Leo! Check it out and pre-order your copy today!
SEED by Cassia Leo
Series: Evergreen Series
About SEED
The explosive continuation of the Evergreen Series from New York Times bestselling author Cassia Leo.
The seeds of doubt have been planted.
Two to six weeks. That's how long it takes, on average, to get a divorce in Oregon.
With Jack convinced I betrayed him, I expect to be served divorce papers within hours of moving out. But weeks pass without word from Jack, and the papers never arrive. Though my heart isn't ready to give up on him, I can't shake the feeling that we may be better off apart. And Isaac is more than happy to help me move on.
But just as I begin to build some semblance of a life and career, a new and improved Jack arrives on my doorstep. Divorce papers are the furthest thing from his mind as he delivers news that both shatters me and restores my faith in the love we shared. But is it too late for us?
Pre Order Now
iBooks | Nook | Kobo | Google Play
SEED will be available on all retailers on March
16, 2018 for the release week special price of $2.99. After release week, it
will resume regular price of $3.99.
Chapter Reveal
May 10, 2015
"Stay with
me, baby," I murmured as I stroked Laurel's hand to keep her from falling
asleep. "You realize our son is going to be born on a very special day."
Her eyes
rolled back in their sockets as another contraction hit. "What?" she groaned.
I had been
trying to keep her mind distracted from the pain with idle conversation about
the things she most liked to talk about. So far, I'd engaged her in a wide
array of topics: Stoic philosophy, ridiculous names for baked goods,
inappropriate wedding songs, and her favorite topic, names for baby boys.
birthdate is going to be May 10th,
2015. In numbers, that five, ten, fifteen."
managed to groan and chuckle at the same time. "You're so American. The rest of
the world would say it's ten, five, fifteen," she said. She breathed in and out
a few times through pursed lips before she continued. "Drea would make fun of
you if she heard you say that."
"It's a
good thing Drea's not here then."
As soon as
I said the words, I wanted to take them back. I didn't want to bring attention
to the fact that, besides Drea, Laurel's mom also was not here.
As if on
cue, Laurel asked, "Where's my mom?"
I squeezed
her soft hand, which seemed to be getting colder. "She's stuck in traffic,
baby. There's an accident. But she's trying to get here as soon as she can."
I didn't
have to lie for Beth. I had to lie for Laurel. I didn't want her to worry that
her mother was abandoning her in her time of need. This was probably the most
important day of Laurel's life, and her mother couldn't be bothered to come
when called.
insisted this was a private moment for Laurel and I to share. According to her,
most grandmothers weren't in the labor and delivery room to see their
grandchildren born. That was the parents' "job." She insisted she would get
here as soon as the baby was born.
The fact
that Beth referred to what I was doing at this moment as a "job" only made me
angrier. I wasn't here with Laurel because it was my job to be here. I was here
because I loved Laurel, and this was where she wanted me to be. If Laurel told
me to leave, I'd leave. She was the one making the decisions today, not me or
Beth or the fucking Dalai Lama.
midwife came into Laurel's room just as the baby's heart rate monitor began to
beep loudly. The swift, hollow tap of our baby's heartbeat had slowed to a
slow, muffled thump. The midwife's black eyebrows shot up as she raced to the
monitor to get a better look at the flashing red numbers.
happening?" Laurel asked, but her eyelids were only half-open as her voice
trailed off. "Is the baby… Is the baby okay?"
Laurel's Filipino midwife, lifted the sheet covering Laurel's legs and her dark
eyes became as wide as planets.
"What is
it?" I demanded as the doctor rushed in.
Florence and tell the others to get the OR ready," the doctor ordered Maisie,
who quickly disappeared into the corridor.
Eastman, what's wrong?" I demanded.
But as my
words fell like stones at our feet, Laurel's hand went slack. Suddenly, four
nurses raced into the room and shoved me aside as they locked the side rails on
Laurel's bed and systematically disconnected her from various machines.
My stomach
went sour as they rushed her out of the labor and delivery room to the
operating room. As I followed closely behind them, I felt as if I were having
an out of body experience. I was watching these medical professionals pushing a
gurney with someone else's unconscious wife. Maybe I'd fallen
asleep in the chair in Laurel's hospital room and this was all a nightmare.
But when
we arrived at the double doors to the OR, someone grabbed my arm to stop me
from entering. That was when I knew this was really happening.
Before the
doors swung shut, I caught a glimpse of three more nurses inside the operating
room. They appeared to be hanging bags of blood on IV stands and prepping
hemorrhaging," Dr. Eastman finally said, as I watched what was going on through
the windows in the double door.
"What do
you mean? How? Why?" I replied as I watched two nurses wheel Laurel's bed into
the center of the OR.
Stratton, please look at me."
I turned
toward the doctor and the grave look in his eyes sent me into a panic. "What's
going on? Tell me what the fuck is happening to my wife!"
"Do you
remember at a previous sonogram when I said we would have to do more sonograms
every three days instead of every week, to keep an eye on the placenta?"
I nodded
vigorously. "Just cut to the chase and tell me what the hell is happening to my
sighed. "The placenta was not over the cervix at the start of labor, but it
seems the contractions have moved it down and Laurel's losing a lot of blood.
We'll have to deliver the baby via C-section."
I tried to
follow a nurse into the OR, but Maisie and Dr. Eastman stopped me again. "I
have to be in there!" I shouted.
"We need
to scrub before we can enter the surgical suite," East said. "Follow me."
In the
washroom, Eastman introduced me to the anesthesiologist, Dr. Brunei, who was
already washed up as a couple of nurses helped him slip into a fresh pair of
"Doctor, I
need you to be straight with me," I said as I set down the disposable nail
brush and proceeded to rub the red Hibiclens soap all over my hands and up to
my elbows. "Should I be worried?"
in labor is not ideal, but it's not uncommon. It's a situation we're always
prepared for, especially with what we saw in the previous sonograms. You're in
good hands today. We're going to deliver your baby and replace the blood your
wife lost. I just need to verify that neither you nor your wife have any
religious objections to receiving blood transfusion?"
I shook my
head as I held my arms under the running water. I couldn't speak. This couldn't
be happening.
Eastman and I were gowned and gloved, we entered the surgical suite in time to
see the nurses using a sheet to lift Laurel's limp body off the hospital bed
and onto the operating gurney, her arm flopped over the edge of the mattress.
Her skin
was drained of the usual golden-peach glow. Her fingers were blue.
No. I
shook my head, unwilling to accept what I was seeing.
I turned
my head to the right and found four-foot-eleven Maisie staring up at me.
very pale, Mr. Stratton. You should sit," she said, motioning to a chair on the
other side of the room, closer to Laurel.
I nodded
as I trailed behind her like a lost puppy. "Thank you," I muttered, but I
didn't take a seat. I couldn't rest when both my babies needed me.
Due to the
hemorrhaging, Laurel would be put under general anesthesia instead of the usual
spinal block used for C-sections. Maisie made it clear that this meant I would
be the first person to hold our baby, not Laurel. I knew this would make Laurel
sad, when she woke and I had to tell her what happened. But I wasn't prepared
for how I would feel about it.
I held
Laurel's hand through the entire surgery, stroking and kissing the back of her
hand and murmuring words of encouragement as if she were awake. When our son
was pulled from her womb, his blue skin covered in blood, I stopped breathing.
Mere seconds passed before he took his first wailing breath of life, but it
felt like an eternity.
As the
nurses cleaned him up, I kept a firm grasp on Laurel's hand while I whispered
in her ear, narrating what was happening. I hoped that somewhere in her
subconscious mind, she was listening, and maybe someday she could piece
together this moment.
smiled as she approached me with the bundle wrapped in a striped baby blanket.
As I took my son in my arms for the first time, I was overwhelmed by a wave of
emotion so powerful, it should have knocked me out of my chair.
streamed down my cheeks as I looked down at his puffy, pink face. "This is my
boy," I said with a chuckle. His tiny body moved in my arms and it my chest
filled with sheer wonder and joy. I shook my head, unable to believe I'd made
something so pure and so real. "This is our son." I put my finger next to his
tiny hand and my heart nearly burst when he grabbed on. I kissed his fingers
the way I'd kissed Laurel's hand earlier and his eyelids fluttered. "Laurel,
baby, I wish you could see this." I looked up at Maisie. "Doesn't he need to be
breastfed or something?" I asked.
smiled. "They will bring her out of anesthesia in a few minutes, once she's
stitched up. For now, he needs to be held by his papa."
The words
echoed in my mind. His papa.
My face
screwed up as I was overcome with emotion. The fear and doubt I'd felt about
becoming a father seemed like a distant memory. I'd never been so filled with
absolute joy in all my life.
I was a
father. I was papa.
Present day
I had let
my jealousy and rage distract me from what was truly important. I'd driven
Laurel away twice, at a time when my pixie needed me most. I knew Laurel didn't
owe me a third chance, which was why I was going to earn my way back into her
arms. And there was only two ways to do that.
One way
was to catch the bastard who stole our happiness. The other way might prove
more difficult. It would involve closing my case files and admitting that my
need for justice was tearing my marriage apart. But I couldn't do that, not
until I gave my quest for justice one final effort. If I couldn't get justice
for my boy by the time Laurel turned thirty next month, I would pack away my
case files and do whatever I took to get her back.
I handed
my suitcase to the guy wearing the fluorescent safety vest, then I climbed the
steps of the private charter plane at exactly eleven a.m. Immediately, I slid
my cell phone out of the interior pocket of my sport coat and called my
assistant, Jade Insley.
morning," she answered cheerily.
"Jade, I
need you to forward all my calls, even the ones to my cell, to your desk phone.
I'm out of town and I don't know when I'll be back."
she replied. "What should I tell the partners?"
"Tell them
I'm visiting family. I'll check in occasionally for messages."
I ended
the call and immediately removed the SIM card from my phone, tossing the tiny
chip over the side of the staircase before I stepped inside the plane. I gave
the attendant my drink order — club soda with lime — then I tucked my cell into
my coat. Sliding the burner phone out of the front pocket of my slacks, I took
a seat in the plush leather seat. I turned the phone on and shot off a text.
Plane taking off. Should land in less than two
hours. We still on for three p.m.?
I'll be there with bells on.
I pulled
my rental car into a space in front of a two-story office building clad in
weathered cedar shingles. The dark tinted windows and lack of signage made it
look like a place one would go to get illegal plastic surgery. Other than my
rented Chevy Tahoe, the only other cars in the lot were a beat up Cadillac
Eldorado and a pristine 80s era cherry-red Porsche.
When I
stepped into the lobby, I was not surprised to find a directory missing a third
of its letters. But I was still able to determine that "SEA D GHE TY PI
2 1" meant Sean Dougherty, Private Investigator was in suite 201 or 211.
That narrowed my options down significantly.
I opted
not to take my chances on the wood-paneled elevator and took the stairs up to
the second floor. The smell of body odor and desperation engulfed me as I
walked down the hallway. The first door I saw was 201 and I quickly reached for
the doorknob, eager to escape the smell in the corridor, but the knob didn't
turn. I rapped on the steel door a few times, certain that no one would hear
me. I was surprised when my knocking was met with a loud grunt from within.
I immediately
lifted the right side of my sport coat, my hand hovering over the gun holstered
on my hip as I waited for the door to open.
"Who is
it?" a gruff voice called from the other side.
Stratton. We have an appointment."
The door
opened slowly and we both smiled when we realized we both have our hands poised
over our sidearms.
I slowly
moved my hand away from my weapon and held it up in front of me. "All good."
The man
lowered his hand and pushed the door wide open. "Good to meet you, Jack," he
said, holding out his hand. "I'm Sean."
We shook,
and I was not at all surprised to find his calloused hand had a killer grip.
"It's really good to meet you," I replied as I stepped inside suite 201.
shoulders relaxed instantly when I realized Sean's office was actually quite
clean and modern and smelled like coffee. Not a hint of despair. Sean was a
sturdy man in his early fifties, with thick salt and pepper hair and muscled
limbs clothed in a crisp button-up and slacks. Not at all what I expected from
a gritty private investigator who worked in the ninth circle of office park
exterior throws people off. Only the people who are serious make it past the
front door," he said as if he were reading my thoughts. "Have a seat." He
continued speaking as I took a seat across the glass desk. "Hood River PD
approved my request to see the file this morning, and I was able to go through
most of it before you got here. We're both obviously most interested in this
memo they received from Boise PD. Have you spoken with Detective Robinson yet?"
I shook my
head. "She couldn't say much over the phone. I have a meeting scheduled with
her tomorrow. She didn't seem very optimistic that this would lead anywhere.
She hasn't had a whole lot of luck with sealed adoption records. But I'm
working on a piece of software to cross-reference birth records and the NCIC
persons files for individuals in Oregon, Washington, and Idaho. I should have
the code finalized and ready to run in a couple of weeks. In the meantime, I
wanted to get you on the case to see if we can track down that adoption decree.
I mean, I don't even have the guy's name. I'm flying blind."
NCIC stood
for National Crime Information Center, the database shared between the FBI and
federal, state, local, and tribal criminal justice users to cooperate on
investigations and policies.
leaned back in his desk chair and cocked an eyebrow. "So what put you onto this
lead anyway? This is a pretty serious accusation."
I shook my
head as I stared at the manila folder on his desk. "Just a hunch, I guess. I
always felt like there was more to Beth than any of us knew."
"And Beth
is your wife's mother, right?"
I nodded.
"Don't get me wrong, Beth was a great mom and I couldn't have asked for a
better grandmother for my son. She… She gave her life trying to protect my boy.
I hold no ill will toward her. But there was always something about her that I
couldn't quite put my finger on.
"I used to
chalk it up to the same mysterious quality Laurel has. A strange, otherworldly
kind of beauty and wit. But with Laurel's mom, there were other signs that I
didn't know the real Beth."
general secretiveness when it came to what caused her divorce from Laurel's
father and stuff like that. It wasn't until someone in our Facebook group
passed on the tip to Boise PD about Mike O'Toole that Detective Robinson
decided to do a little digging into Beth's past."
"So who's
Mike O'Toole?"
I waved
off the question. "A dead lead, but it did get Robinson asking questions and
that's why I'm here. The PI I spoke to in Portland told me that it could take
years to win a battle to unseal adoption records. She said my best bet, if the
suspect is living here in Idaho, would be to try to find someone who could
track him down here. So here I am, hoping like hell you can help me find the
piece of shit that killed my son, because… I'm on the verge of losing
Sean is
silent for a long while as he stares at the glass desktop, and when he finally
looks up, his square face is fixed with a tight smile. "Well, you were honest
with me, so I guess it's my turn for a little show and tell." He reaches behind
him, opens the top drawer of a two-drawer file cabinet, and pulls out a silver
picture frame. "This is my Rosie," he says, placing the picture on top of his
desk so I could see the photo of a teenage girl with wavy blonde hair and a
beaming smile. "Rose hated when I called her Rosie," he said, staring at the
picture with a wistful look in his steel-gray eyes.
beautiful," I said, stopping myself before I could say she reminded me a bit of
"Rose was
seventeen when she went to an ice skating rink with some friends. Same as she'd
done every winter since she was eight years old. But this time, she went
outside to have a smoke. A nasty habit. I kept grounding her to try to get her
to stop, but she just wouldn't listen. She was too pigheaded." He finally
looked up and met my gaze. "That was the last we saw of her until her body was
discovered two months later, in a creek forty miles away."
I clenched
my jaw as I imagined how I would have felt if I'd had seventeen years with
Junior before he was murdered. Or if, God forbid, it had been Laurel who had
been taken away from me. I wouldn't want to live in a world without Laurel.
"That was
a knockout punch. I was down for the count. No coming back from that, I
thought," Sean continued. "So I doubled down on how fast I could wreck my life.
I was a financial crimes detective at the time, but I began sleeping in my
office, poring over the case files day and night. I became obsessed."
I lowered
my gaze as his words shamed me. All the nights I'd spent sleeping on the couch
in my home office instead of in the bedroom with Laurel were mirrored in Sean's
story. And somehow, I didn't think his story had a happy ending.
"Did you
find out who did it?"
smiled as he shook his head. "Nope. I lost my job. Lost my marriage. Lost my
house. That bastard took my daughter from me, but I willingly gave him
everything else. You understand?"
I nodded
in silence. For the first time in my life, I couldn't think of a single cynical
thing to say. I was only in this office because this was my last resort. I
couldn't come back to Laurel emptyhanded. I'd given her every material thing
she could ever want. I gave her shelter and security. I gave her my love. But I
hadn't given her my full attention.
I knew myself too well to know that I would not be able to focus on my marriage
and work until I was certain I'd done everything I could for Junior. And, yes,
even for Beth. She may have had her secrets, but I meant it when I said Junior
could not have asked for a better grandmother. She deserved justice as much as
my boy did.
Dougherty and the software program I was working on, which I had dubbed PNW
Checkmate, were my last hope. If the software helped us find Junior's killer, I
would expand the software to include all fifty states and territories. For now,
I had to focus on this area, and specifically Boise. If Ava Robinson's
suspicions were correct that Beth and Junior's murders were not random, this
was surely the missing piece of the puzzle we needed to help us crack this
case. Laurel and I might finally be able to turn the page on this gruesome
chapter of our lives.
Sean and I
chatted for more than two hours. I filled in any holes in the case file he'd
received from the Hood River Police Department. I laid out my suspicions about
Beth's past, information I'd gleaned through conversations with Beth and Laurel
over the years. The most interesting tidbit being the time Laurel told me her
mother had left her father for a few months when she was about five years old.
It wasn't definitive evidence, but it was one brushstroke in a colorful picture
of a woman who lived her life with as much verve as the flowers she so
carefully nurtured.
you do, do not—I repeat, do not attempt to approach any potential
suspects or interviewees on your own. You hear me?" He glared at me with his
thick eyebrows raised, awaiting my agreement.
"You have
my word," I replied, probably not as definitively as I should have.
serious, Jack. Don't get yourself killed or arrested for this shit. It's not
worth it. Tell me you understand."
I nodded.
"I understand," I said with a bit more vigor.
He eyed me
warily. "I'll handle all interviews. You've got too much at ´stake. Too many
emotions that pose a threat here. And I'm the experienced interrogator. So this
is not a request. This is an order. You hear me?"
I looked
him dead in the eye. "Loud and clear."


text:
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text:
Coming from the Arabic root samaha, musamaha (tolerance) means to forgive and to pardon. The word hosgoru is used in Turkish and the word tolerance in English. As a term, it is used for the understanding and gentle behavior towards everyone, without prejudice, of someone who is mature and good-intentioned. Truly this is a high virtue possessed only by people of superior morality. Both too much and too little of tolerance can lead to harmful results.
Moral principles have an important place in the divine messages of prophets brought from Allah's presence. Tolerance has a unique place among these moral principles. The religion brought by Prophet Muhammad (pbuh) being named "Islam" shows that, along with other meanings, it is a religion of forgiveness and tolerance. In fact, it is also possible to find meanings like peace and reconciliation among the different meanings of the word Islam.
Let's look at some of the verses in the Quran related to this topic: "(The righteous are) those who spend (freely), whether in prosperity, or in adversity; who restrain anger, and pardon (all) men; for God loves those who do good." (1) "Help ye one another in righteousness and piety, but help ye not one another in sin and rancor: fear God, for God is strict in punishment."(2) "The believers are but a single brotherhood: so make peace and reconciliation between your two (contending) brothers; and fear God, that ye may receive mercy." (3)
"O ye who believe! Truly, among your wives and your children are (some that are) enemies to yourselves: so beware of them! But if ye forgive and overlook, and cover up (their faults), verily God is Oft-Forgiving, Most Merciful." (4)
The requirements for being tolerant:
1- To take the nafs to account: "Do not overlook your sins due to loving yourself." (5)
2- To cover people's faults: In one hadith the Prophet says: "Whoever covers someone's fault in this world, Allah will cover his faults on Doomsday." (6)
3- To overcome anger: The righteous... who restrain anger and pardon (all) men; for God loves those who do good." (7) "The powerful one is not someone who defeats his opponent in wrestling. It is the one who restrains himself during times of anger." (8)
4- To be forgiving: "(Hey Nabi!) Hold on to forgiveness; command what is right; But turn away from the ignorant."
5- Do not curse others: Prophet Muhammad (pbuh) said, "I was not sent to curse. I was sent as a mercy." (9)
6- Do not be suspicious: "O ye who believe! Avoid suspicion as much as possible: for suspicion in some cases is a sin." (10)
7- Avoid haughtiness and pride: "And swell not thy cheek (for pride) at men, nor walk in insolence through the earth; for God loveth not any arrogant boaster." (11) On this subject the Prophet states: "It is enough evil to condescend on one's Muslim brother." (12)
8- Do not make fun of people: "O ye who believe! Let not some men among you laugh at others: it may be that the (latter) are better than the former." (13)
9- To be patient: There are more than seventy verses in the Quran that mention patience. The Prophet said: "No one has been blessed with a better gift than patience." (14)
Tolerance in family life establishes good behavior towards wives, love and compassion for children, and just action towards parents. On these subjects Prophet Muhammad (pbuh) is an exemplary model and character. It is well-known that he approached his wives with mercy, goodness, patience and love.
A monument of mercy towards his children and grandchildren, the Prophet continuously showed interest in them and treated them with love and gentleness. He allowed his grandsons Hassan and Hussain to ride on his shoulders while he prayed. It is possible to multiply these examples.
There is no coercion in Islam regarding religion and belief. It is not possible to force a person to change his belief; it can only be done with persuasion and the approval of the person. Freedom of belief is one of the leading rights of man. If religion were communicated to people with fear and oppression, there would be no meaning to belief. It was left up to people to direct their lives with free will. Because they have to give account to Allah, people were given freedom of choice. If, to the contrary, people had been coerced, it would have been unjust. Related to there being no force in religion, Allah says, "Let there be no compulsion in religion. Truth stands out clear from error: whoever rejects evil and believes in God hath grasped the most trustworthy hand-hold that never breaks. And God knoweth and heareth all things." (15) Another verse regarding this matter is as follows: "If it had been thy Lord's will, they would all have believed, all who are on earth! Wilt thou compel mankind, against their will, to believe!" (16)
Places of worship in divine religions have the characteristic of being sacred. Just as the mosques of Muslims are protected, places of worship in other religions are also under protection.
In fact, the Quran states on this issue: "Did not God check one set of people by means of another, there would surely have been pulled down monasteries, churches, synagogues, and mosques, in which the name of God is commemorated in abundant measure." (17)
Just as a Muslim has the right to go to a mosque and perform the worship his faith requires, a Christian has the right to go to a church and a Jew has the right to go to a temple or synagogue for worship. Prophet Muhammad, who lived together with Jews for some time in the Medina community, did not try and curtail the worship of Jews. At the same time, it is known that he similarly permitted Christians to practice their faith.
After the migration, the Prophet acted positively and moderately towards the Jews, who were an important element of Medina and who were not very happy with his coming. In fact, he invited them to a common word, prayed towards their qibla in Jerusalem and allowed Muslims to eat the meat of animals slaughtered by the Jews and to marry their chaste women. In order to allow them to look favorably on the religion of Islam, he showed respect to a Jewish funeral procession passing in front of him; he stood up and recommended that his Companions do so as well. Also, although he forbade the pagans to enter the masjid, he allowed Jews, who were among the People of the Book, to enter. We know that some Jews, even though their numbers were small, became Muslim as a result of the Prophet's positive attitude towards Jews. Jews like Abdullah b. Selâm, Sa'lebe b. Sa'ye, Esîd b. Sa'ye, Esed b. Ubeyd, Muhayrık, and Meymûn b. Yâmin accepted Islam. The Jews also accepted Muhammad as head of state with the constitution. In addition, they were to defend the city together with Muslims in case of any external threat or attack. The Medina constitution established the freedom of religion and faith and the security of life and property to its parties. However, in spite of this positive and moderate approach, the Jews did not remain loyal to the agreement, and they cooperated with the pagans and tried to stab Muslims in the back. As a result, the Prophet had to fight with them and force them out of Medina.
Prophet Muhammad acted extremely carefully in regard to the rights of peoples the Islamic state had agreements with. In regard to this the Prophet said, "Whoever harms a non-Muslim subject will have harmed me. Whoever hurts me will have angered Allah." Again, in a hadith related by Abu Davud, the Prophet said, "On Doomsday I am not going to accept anyone who oppressed a non-Muslim subject with whom we have agreement, or violated their rights, or burdened them with more responsibility than they could carry or made them do something they did not want to do." The Prophet and the Rightly-Guided caliphs were protectors of the rights and privileges of non-Muslim citizens.
Respect to Allah's commands and mercy to His creatures, and tolerance for others out of love for their Creator is one of Islam's basic principles. In all relationships the Prophet gave precedence to being reasonable and moderate, to establishing ties of friendship and love in place of enmity, to gentleness instead of anger, rage, revenge and getting even, and to kindness rather than evil. Indicating that goodness lay in the foundation of all religions, he showed respect to all prophets and sacred books.
Muhammad (pbuh) stated that all people should be treated well and he himself became an example with his practices. His basic reference on this subject was the Quran: "Wert thou severe or harsh-hearted, they would have broken away from about thee. (18) "Say to My servants that they should (only) say those things that are best." (19) "Do not curse those who take another god for they, exceeding their limits, curse Allah." (20)
One day while the Prophet was sitting in the masjid with his Companions, a Bedouin came in and began to urinate in a corner of the masjid. The Companions angrily shouted at the man to stop, but the Prophet immediately intervened and said, "Leave the man alone and let him finish his job." Then he commanded that a bucket of water be emptied there. He called the Bedouin and explained that he was in a masjid and that it would not be right to defile it. With pleasant language and a sweet tongue, he convinced the man that masjids are places where Allah is remembered, prayer is made and the Quran is read.
According to my findings, these are the issues on which the Prophet did not show tolerance:
1-Prophet Muhammad (pbuh) hindered those who prevented the call of Islam and showed open enmity towards the Islamic state; he disapproved of those who displayed open enmity to the religion of Islam in their poems and those who incited the pagans against Muslims. The incident involving the Jewish poet Qa'b ibn al-Ashraf is one of the best examples of this.
2-He refused those who wanted pardon for those whose crimes were proven, and he was not tolerant on this subject. The Prophet showed his sensitivity on this topic as follows: "I swear to Allah that if the thief had been my daughter Fatima, I would have cut off her hand."
3-Loyalty to tribalism and consanguinity (where it constituted disloyalty to the Truth and Justice) was prohibited, and he was not tolerant on this issue.
4-The Prophet was extremely careful in regard to individual rights and he prohibited their violation.
5-He was not tolerant in regard to preventing evil and the open practice of haram, etc.
Throughout Prophet Muhammad's lifetime, tolerance was one of the most basic ideas underlying his behavior. He called people to religion and approached them with tolerance in light of the verse, "Invite all to the way of thy Lord with wisdom and beautiful preaching; and argue with them in ways that are best and most gracious." (21) Others being harsh and rude in response to this call did not make him forego this principle. During the Taif campaign his being forgiving towards the ugly attack made against him and his praying for their reformation instead of their destruction is a good example of this.
There are lessons and wisdom to be gained by the modern world in the Prophet's understanding of tolerance and its application in Islamic history. Those who indiscriminately describe Muslims as fanatical, aggressive and intolerant, need to look at and analyze the life and actions of Prophet Muhammad and Islamic history.
1) Al-i Imran, 3/134.
2) Al-Maide, 5/2.
3) Al-Hujurat, 49/10.
4) Al-Tagabun, 64/14.
5) Al-Najm, 53/4
6) Muslim, Birr, 12; Ahmed b. Hanbel, Musned, VI, 145
7) 3 Al-i Imran, 134
8) Bukhari, Adab, 76; Muslim, Birr, 107, 108
9) Muslim, Birr, 87
10) Al-Hujurat, 49/12
11) Al-Loqman, 31/18
12) Muslim, Birr, 32
13) Al-Hujurat, 49/11
14) Bukhari, Zekat, 50
15) Al-Baqara, 2/256.
16) Al-Yunus, 10/99.
17) Al-Hajj, 22/40.
18) Al-i İmran, 3/159.
19) Isra, 17/53.
20) Al-Nisa, 4/148
21) Al-Nahl, 16/125
Ismail Hakki Atceken, PhD


text:
Maurice Chacron (2007), Scholarpedia, 2(1):1411. | doi:10.4249/scholarpedia.1411 | revision #84863 [link to/cite this article] |
Electrolocation is a modality of animal perception through the sensing of electric fields that can be used for:
- object detection
- intraspecies communication
- defensive and offensive behavior such as prey stunning and warding off predators
Behavioral evidence for the normal sensing of electric fields came from the work of Lismann (Lismann, 1958; Lismann and Machin, 1958; Machin and Lismann, 1960), thus establishing a new field of research. Electrosensitive neurons have been found in a wide variety of species including:
- elasmobranchs such as rays and skates (Murray, 1960; Kalmijn, 1966)
- teleost fish (Lismann, 1958; Lismann and Machin, 1958; Machin and Lismann, 1960)
- mammals such as the duck-billed platypus (Scheich et al., 1986)
The study of electrosensory systems is particularly attractive for anatomical, physiological, behavioral, and evolution studies and has already been extensively reviewed (Bullock and Heiligenberg, 1986; Turner et al., 1999; Zakon, 2003; Sawtell et al., 2005; Fortune et al., 2006; Zakon et al., 2006).
Passive Electrolocation
Passive electrolocation was first discovered through observations that receptors in elasmobranchs, Ampullae of Lorenzini, were sensitive to changes in weak electric fields (Murray, 1960). Since then, another category of electroreceptors called ampullary receptors have been discovered in teleost fish that evolved independently from those found in elasmobranchs (Bennett, 1971).
Active Electrolocation
Some fish, called weakly electric fish, actively generate electric fields through electric organs and possess specialized neural circuitry to detect distortions of that field caused by objects. Unlike strongly electric fish (e.g. electric eels), electric fields produced by weakly electric fish are low in amplitude (~1 mV/cm) and are used for electrolocation and electrocommunication rather than electro-offense or defense (Bullock and Heiligenberg, 1986). Active electrolocation has evolved independently in both African Mormyriform and south American Gymnotiform weakly electric fish that comprise hundreds of species (Bennett, 1971). Active electroreception requires specialized electroreceptors called tuberous receptors. It should also be noted that the spatiotemporal characteristics of the electric organ discharge (EOD) vary widely: some species have wavetype EODs whereas other species have pulse-type EODs (Bennett et al., 1961; Bennett, 1971; Hopkins and Heiligenberg, 1978; Bass, 1986). For wavetype species, the EOD is highly periodic with frequencies ranging from 60 Hz to 2000 Hz depending on the species. For pulse-type species, the pulse frequency is much lower and does not exceed 90 Hz (Bass, 1986). Pulse-type fish often display a novelty response characterized by a transient increase in EOD frequency upon encountering a novel object in the environment (Toerring and Moller, 1984; Schwarz and Von der Emde, 2000).
Electroreceptor Categories
Electroreceptor afferents typically form canals at the skin surface. Epithelial hair cells are found that the bottom of each canal and form excitatory synapses with the afferent nerve containing a spike initiation zone. The afferent nerve then transmits action potentials to the brain (figure 2). Some receptors are sensitive to external electric fields while others are sensitive to distortions of the self-produced EOD.
Ampullary receptors
Ampullary receptors detect very weak low frequency electric fields and are used to detect prey (Parker and Van Heusen, 1917; Kalmijn, 1974; Zakon, 1986). Recent work has used computational data analysis and modeling to understand how the dynamics present in the ampullary electroreceptors of the paddlefish contribute to information processing. Recordings from epithelial hair cells located in the pore have revealed a tendency for these to oscillate ~30 Hz. As well, the spike initiation zone of the afferent nerve located in the Ganglia tends to fire action potentials in a quasi-periodic manner ~ 75 Hz (figure 3). A modeling study was successful in explaining interactions between the hair cell as well as the spike initiation zone (Neiman and Russell, 2001; Neiman and Russell, 2004). These interactions manifest themselves as peaks in the power spectrum as frequencies related to the difference and sum of the frequencies of the hair cell oscillation and the afferent nerve firing.
Behavioral stochastic resonance has been demonstrated in the paddlefish. Thus, increased environmental noise caused for example by a daphnia swarm, actually facilitates single daphnia capture by juvenile paddlefish (Russell et al. 1999). It is thought that hair cell oscillations might mediate this effect by increasing receptor sensitivity to values near threshold (Neiman and Russell, 2004). Alternatively, the internal noise generated from epithelial oscillations may serve to randomize the timing of spikes from different afferents. This would decrease the probability of coincident firing in the absence of external stimuli and thus lower the probability of false alarms.
Ampullary electroreceptors of paddlefish also display bursting when driven by an external stimuli. Multiunit recordings have shown that such receptors tend to fire synchronous bursts in response to a common stimulus (Neiman and Russell, 2002). Higher order neurons may possess specialized circuitry to detect these synchronous bursts. Further work is however necessary in order to elucidate the mechanisms by which higher order neurons in paddlefish decode information from electroreceptor afferents.
Tuberous receptors
Tuberous receptors are found only in two groups of teleost fish: Mormyriforms and Gymnotiforms (Bullock 1982). In both groups, tuberous receptors can be distinguished into two categories. Phase coders are sensitive to changes in EOD frequency while amplitude coders are sensitive to changes in EOD amplitude. We will briefly examine the role of phase coders and focus on the role of amplitude coders in this review.
Phase coding in pulse-type fish
Knollenorgans in mormyrid fish have high sensitivities and can respond to both the animal's own pulse-type EOD as well as the discharges of other fish (Bennett 1965; 1971; Bell, 1986). These afferents typically respond to stimuli with a single action potential (Bennett 1965). They are generally insensitive to stimulus intensity. As such, it was proposed that these afferents are used exclusively to detect and measure the discharges of other fish (Bell, 1986).
Phase coding in wave-type fish
In gymnotiforms, T-type electroreceptors display 1:1 phase-locking with respect to the EOD (i.e. 1 action potential per EOD cycle) at a fixed phase. Earlier studies have shown that measurements of phase were essential for a behavior known as the jamming avoidance response (JAR) which has been extensively reviewed elsewhere (Heiligenberg, 1991). However, it is likely that they serve other functions as not all wave-type fish display a JAR. Comparative studies of electric fish species that do and do not display a JAR have revealed important anatomical, physiological, and morphological differences (Matsubara, 1981; Losier and Matsubara, 1990). Further, a recent computational study has shown that phase coders might have other functions even in species that display the JAR. Specifically, T-units can actually encode amplitude modulations quite well (Carlson and Kawasaki 2006). Further studies are necessary to verify whether information about amplitude modulations contained in T-unit spike trains is actually decoded in higher centers and, if so, by which mechanisms.
Amplitude coding in pulse-type fish
Mormyromast organs in Mormyriform weakly electric fish use a temporal code to represent changes in EOD amplitude. It was found that there was a very precise relationship between amplitude and the latency to first afferent spike after the EOD pulse: larger EOD amplitudes will give rise to smaller latencies and vice-versa (Szabo and Hagiwara, 1967; Bell, 1990; Sawtell et al., 2006). A recent study has used information theory to quantitatively characterize the latency code used by mormyromast electroreceptors in mormyriform electric fish (Sawtell et al., 2006). This study has found that the first spike latency in mormyromast electroreceptors did not solely depend on the EOD amplitude but also depended on the recent history of EOD amplitudes and interpulse intervals. It was found that mormyromast electroreceptor spike trains contained significant information about EOD amplitude and that over 80% of this information could be recovered by a linear stimulus reconstruction (Sawtell et al., 2006).
Amplitude coding in wave-type fish
P-type electroreceptors in wave-type fish respond to changes in EOD amplitude with changes in firing rate (figure 4). While initial studies of these receptors used simple stimuli such as step increases or sinewaves, more recent studies have used information theory to characterize P-unit responses to noise stimuli (Gabbiani et al., 1996; Wessel et al., 1996; Metzner et al., 1998; Gabbiani and Metzner, 1999; Kreiman et al., 2000; Chacron et al., 2005c; Carlson and Kawasaki, 2006; Chacron, 2006). P-units follow changes in EOD amplitude with great fidelity (Wessel et al., 1996) and linear decoding algorithms can often recover in excess of 80% of the information contained in their spike trains (Chacron, 2006). Spike trains from P-units are furthermore largely insensitive to addition or deletion of spike timing jitter, implying that most, if not all, the information is contained in their time dependent firing rate (Kreiman et al., 2000; Chacron, 2006). As such, there are large differences between the neural codes used by wave-type electric fish, rate codes, and those used by pulse-type electric fish, temporal codes.
P-unit activity is phase-locked to the EOD since the probability of firing is greatest close to EOD local maxima (Bastian, 1981; Xu et al., 1996; Nelson et al., 1997). Initial studies have found that P-unit tuning curves were high-pass (Bastian, 1981) and an ad-hoc model was developed that accounted for these high-pass characteristics (Nelson et al., 1997). However, it was later observed that intrinsic dynamics in P-units gave rise to lower variability than expected at low frequencies (Ratnam and Nelson, 2000). A phenomenological leaky integrate-and-fire with threshold fatigue was found to reproduce experimental data (Chacron et al., 2000; Chacron et al., 2001b, a, 2003a; Chacron et al., 2003b; Chacron et al., 2004a), including the low variability at low frequencies (Chacron et al., 2001a). Further understanding of the actual mechanism by which intrinsic threshold dynamics in the model gave rise to lower variability was obtained through theoretical studies showing that negative correlations between subsequent interspike intervals gave rise to noise shaping (Chacron et al., 2004b, c; Lindner et al., 2005b): the total noise power is conserved but noise power is redistributed. In particular, negative ISI correlations give rise to reduced noise power at low frequencies, thereby improving signal transmission at these frequencies. Subsequent experimental studies have verified that P-type electroreceptors indeed displayed noise shaping as predicted from theory (Chacron et al., 2005c). Calcium-activated potassium currents found in electroreceptors (Bennett and Obara, 1986) most likely underlie this noise shaping.
More recent studies have focused on responses of P-units to natural communication signals in weakly electric fish: chirps. Chirps are brief interruptions in the EOD signal used by males to communicate during agonistic encounters (small chirps) and during courtship behaviour (large chirps). It was found that small chirps led to a phase resetting of the ongoing sinusoidal amplitude modulation that occurs during agonistic situations (Benda et al., 2005) whereas large chirps lead to transient desynchronization of P-type electroreceptor activity (Benda et al., 2006).
A recent computational study has shown that P-type electroreceptors could also encode phase-modulations of the EOD (Carlson and Kawasaki 2006). These results suggest that information about amplitude and phase modulation of the EOD are not completely segregated between P and T-units in wave-type gymnotiform fish.
Second order sensory neurons
P-type electroreceptor afferents in Gymnotiform fish synapse unto pyramidal cells whereas mormyromast afferents in Mormyriform fish contact large fusiform and large ganglion cells within the electrosensory lateral line lobe (figure 5). In both groups, the efferent cells also receive large amounts of feedback from higher centers (Maler, 1979; Maler et al., 1981; Bell et al., 1997c; Sawtell et al., 2005) and several studies have focused on functional roles for this input.
Cancellation of redundant stimuli
As weakly electric fish generate an active electric field, changes in posture that routinely occur during behaviour can give rise to large changes in EOD strength on the body surface which could mask other behaviourally relevant stimuli. It was initially found that, while electroreceptor afferents were strongly driven by such changes, second order sensory neurons were largely insensitive (Bell, 1981, 1982; Bastian, 1995, 1996a, b; Bell et al., 1997b; Bastian, 1998; Bastian, 1999). It should be noted that similar mechanisms are also found in elasmobranchs were proprioceptive input cancels electrical distortions caused by gill or fin movements (Montgomery and Bodznick, 1994; Hjelmstad et al., 1996). A recent review also highlights similarities with other systems (Cullen, 2004).
The circuitry underlying the cancellation of reafferent stimuli in weakly electric fish is similar in both mormyriform and gymnotiform fish (figure 5). In both instances, electrosensory reafferent signals from electroreceptor afferents are cancelled by a "negative image" provided by feedback input. Subsequent studies have shown that this cancellation is highly plastic: changes in the strength of the reafferent stimulus lead to appropriate changes in the strength of the negative image through plasticity (Bastian, 1995, 1996b, a; Bell et al., 1997b; Bell et al., 1997a; Bell et al., 1997c; Bastian, 1998; Bastian, 1999; Mohr et al., 2003). We now concentrate on the differences between mormyriform and gymnotiform electric fish.
In mormyriform pulse-type electric fish, large ganglion and fusiform cells receive a direct corollary discharge signal through feedback pathways. An anti-Hebbian form of spike timing dependent plasticity has been shown to mediate adaptive cancellation of predictable sensory input caused by EOD pulses (Bell et al., 1997a). Further theoretical studies have investigated the computational consequences of these asymmetric learning rules (Roberts, 1999; Roberts and Bell, 2000, 2002; Williams et al., 2003).
In gymnotiform wave-type fish, pyramidal cells do not receive any direct corollary discharge signal. Hence, cancellation of purely electrosensory stimuli must make use of the sensory reafferent input provided by electroreceptors. Previous studies have documented large heterogeneities in pyramidal cell morphology (Bastian and Courtright, 1991; Bastian and Nguyenkim, 2001), receptor density (Zupanc et al., 1992; Berman et al., 1995), and responses to sensory input (Bastian et al., 2002). A recent study has shown that pyramidal cells also displayed differential levels of adaptive cancellation of electrosensory stimuli: cells with large apical dendrites showed the most plasticity whereas cells with small apical dendrites showed almost no plasticity (Bastian et al., 2004). A network model predicted that, in order to maximize the efficiency of cancellation, only non-plastic pyramidal cells should project to higher centers involved in generating the negative image and this prediction was then verified anatomically (Bastian et al., 2004).
It should be noted that cancellation of reafferent stimuli is not necessarily adaptive. An example of this is found in neurons of the rhombencephalic nucleus of the lateral line lobe (nLLL) in mormyrid fish. These neurons receive direct input from knollenorgans through gap junction synapses as well as GABAergic inhibitory corollary discharge input from the pacemaker cells(Maler and Mugnaini, 1987). Physiological experiments have shown that, when stimulated by the animal's own EOD, neurons of the nLLL received precise inhibition that blocked their response to the knollenorgan input (Szabo et al. 1979). In contrast with the precise spike-timing dependent plasticity described in ganglion cells, the inhibitory input unto nLLL neurons does not seem to be plastic (Bell, 1986). It has been hypothesized that the animal's own EOD and the lack of sensitivity of Knollenorgan afferents to stimulus intensity might explain this lack of plasticity.
Bursting is prominent in the central nervous system and has been extensively characterized in the pyramidal cells of gymnotiform wave-type fish both in vitro and in vivo. In vitro studies have extensively characterized the burst discharge of pyramidal cells (Turner et al., 1994; Lemon and Turner, 2000; Doiron et al., 2003a; Noonan et al., 2003; Fernandez et al., 2005). Burst firing occurs intrinsically and is mediated by a somato-dendritic interaction: somatic action potentials backpropagate through the dendritic tree and can activate dendritic sodium channels, thereby causing dendritic action potentials. These dendritic action potentials then invade the soma, causing a depolarising after potential (DAP) that can thus cause another somatic spike. This "ping-pong" mechanism continues and the time interval between successive somatic spikes is shortened until the dendritic refractory period is reached. At this point, backpropagation fails to elicit a dendritic spike, thus terminating the burst (figure 5). A detailed compartmental model reproducing this burst pattern was developed (Doiron et al., 2001). Subsequently, a reduced two-compartmental version known as the "ghostburster" was obtained (Doiron et al., 2002). Detailed nonlinear dynamical analysis using a separation into fast-slow subsystems showed that the ghostburster did not fit into the same category as other burst models (Izhikevich, 2000) as the burst termination is connected with a bifurcation from a period 1 to a period 2 limit cycle.
Recent studies have also looked at the functional implications of burst firing in vivo. Pyramidal cell bursts were initially found to reliably detect particular features of the stimulus (Gabbiani et al., 1996; Metzner et al., 1998; Gabbiani and Metzner, 1999; Krahe et al., 2002). More recently, it was shown that bursts and isolated spikes within a pyramidal cell's spike train formed two separate information channels (Oswald et al., 2004): bursts selectively encoded the low frequency components of the stimulus while single spikes selectively encoded the high frequency components of the stimulus. Furthermore, it appears that the pyramidal cell bursting seen in vivo is related to the bursting seen in vitro as dendritic failures can be seen in vivo (Oswald et al., 2004). However, further studies are needed in order to understand how bursting seen in vitro is affected by in vivo conditions.
Contextual coding
Like every animal, weakly electric fish must detect stimuli with vastly different spatiotemporal characteristics in order to survive in their environment. In particular, these fish must detect electrosensory signals caused by prey as well as those caused by conspecifics. Behavioral studies in gymnotiform wave-type fish have shown that the stimuli spatially localized caused by prey contained low frequencies and peaked at 10 Hz (Nelson and MacIver, 1999). In contrast, spatially diffuse stimuli used during communication can contain high frequencies between 50 and 100 Hz (Zupanc and Maler, 1993). Recent studies have used stimulation geometries to mimic prey and communication stimuli and will be henceforth referred to as local and global stimulation, respectively (figure 6).
Network Oscillations
Recent work has focused on pyramidal cell oscillatory dynamics under local and global stimulation in gymnotiform weakly electric fish. It was found that pyramidal cells tended to display oscillatory dynamics under global but not local stimulation (Doiron et al., 2003b). A network model using diffuse delayed inhibitory feedback could reproduce these results with surprising accuracy and predicted that activation of diffuse inhibitory feedback unto pyramidal cells by diffuse global stimuli caused the oscillation. This prediction was verified experimentally through reversible pharmacological blockade of inhibitory feedback, thereby blocking the oscillation. Further studies then showed that spatial correlations in the stimulus were required to give rise to the oscillation (Doiron et al., 2004; Lindner et al., 2005a).
Tuning shift
Other studies have focused on correlating pyramidal cell activity with the stimulus under local and global geometry. It was initially found that pyramidal cells gave vastly different responses to stimuli delivered both locally (mimicking prey) and globally (mimicking communication): whereas responses to local stimuli are tonic in general, responses to global stimuli are more phasic (Bastian et al., 2002). It was then shown that pyramidal cell tuning was geometry dependent: pyramidal cells switch their preferred frequency range from low (<10 Hz) to high (>25 Hz) frequencies contingent on switching the stimulus geometry from local to global (Chacron et al., 2003c). The close match between the preferred frequency tuning of pyramidal cells under local and global geometry and the frequency content of prey and communication stimuli, respectively, suggests that this switch is behaviourally relevant. Further studies have elucidated the origins of this switch in tuning: activation of diffuse feedback input in the form of a negative image by global stimuli has been shown to attenuate the low-frequency response of pyramidal cells both experimentally and in models (Bastian et al., 2004; Chacron et al., 2005a; Chacron et al., 2005b; Chacron, 2006) whereas spatial saturation of the receptive field center by global stimulation will increase pyramidal cell responses to high frequency stimuli (Chacron et al., 2003c; Chacron, 2006).
Higher Order Processing
In mormyriform as well as gymnotiform weakly electric fish, efferent projections from the electrosensory lateral line lobe contact neurons within the torus semicircularis (figure 3). Recent work on gymnotiform fish has focused on understanding the cellular mechanisms by which Toral neurons integrate information from pyramidal cells. In vivo patch clamp studies (Rose and Fortune, 1996) have established that Toral neurons possess subthreshold activated sodium conductances that lead to nonlinear amplification of coincident synaptic input (Fortune and Rose, 1997; Fortune and Rose, 2003).
Burst Selective cells in Torus
Fortune and Rose (1997) showed that some Toral neurons were selectively responsive to frequencies typically associated with prey stimuli (<10 Hz). Interestingly, these same cells showed marked paired pulse facilitation to direct stimulation of the pyramidal cell axon bundle with 10 msec interpulse interval (Fortune and Rose, 2000; Fortune and Rose, 2001), which corresponds to pyramidal cell bursts. This suggests that synaptic facilitation enhances the transmission of pyramidal cell bursts in the Torus. Furthermore, as pyramidal cell bursts selectively encode low frequencies (Oswald et al., 2004), this suggests that burst firing is primarily involved in the coding of prey stimuli in gymnotiform weakly electric fish. Furthermore, the presence of subthreshold sodium conductances (Fortune and Rose, 1997; Fortune and Rose, 2003) suggests that Toral neurons will maximally respond to synchronous bursts from pyramidal cells.
Origins of directional selectivity
While pyramidal cells are largely insensitive to the direction of moving objects, a recent study has shown that directional selectivity to moving objects could be induced by gamma-range (20-50 Hz) oscillatory stimuli (Ramcharitar et al., 2006). These oscillations furthermore occur naturally when groups of fish are in proximity (Tan et al., 2005). These results further show that this selectivity is correlated with the magnitude of short-term synaptic depression caused by these oscillatory stimuli (Ramcharitar et al., 2006). Previous models of synaptic depression have shown mechanisms by which such depression could lead to directional selectivity (Chance et al., 1998) but further studies are needed to see if these mechanisms are indeed responsible for enhanced directional selectivity in the Torus.
Future Directions
- While information theory and other computational analyses have been used to characterized coding in both the p-type electroreceptors and pyramidal cell of wavetype weakly electric fish, these techniques are only beginning to be used for pulse-type fish (Sawtell et al., 2006). Further studies are needed to understand information processing by neurons within the electrosensory lateral line lobe in these fish.
- In wavetype fish, we are starting to understand the principles by which information is encoded by single pyramidal cells. Further studies are however needed to understand how populations of pyramidal cells encode sensory information. Moreover, the mechanisms by which this information is being decoded by neurons within the Torus semicircularis are just starting to be elucidated.
- In wavetype fish, burst firing in pyramidal cells seems to encode prey but not communication stimuli. As such, there must be mechanisms to control pyramidal cells burst firing. Pyramidal cells receive massive amounts of feedback as well as cholinergic and serotonergic input. Further experimental studies complemented by modeling are needed to understand the functional roles of such inputs and their effects on pyramidal cells burst firing.
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Internal references
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- Arkady Pikovsky and Michael Rosenblum (2007) Synchronization. Scholarpedia, 2(12):1459.
External links
Laboratories working on electrolocation:
See Also
Bursting, Directional Selectivity, Neuronal Codes, Sensory Systems


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Rockers React: Weezer + Others Comment on Ric Ocasek's Death
Following yesterday's news of Ric Ocasek's death, artists close to the Cars mastermind offered comment on the rock and roll icon. Those include tributes from bands Ocasek produced in a long career behind the boards — such as Weezer, Nada Surf and Suicide — as well as entertainers otherwise touched by the singer and songwriter.
The Killers frontman Brandon Flowers, who inducted the Cars into the Rock and Roll Hall of Fame last year, shared an email he wrote Ocasek after the musician died Sunday (Sept. 15) at the age of 75. Other rock musicians (including members of KISS, Guns N' Roses and more) also gave their condolences. See them toward the bottom of this post.
"The Weezer family is devastated by the loss of our friend and mentor Ric Ocasek, who passed away Sunday," Weezer shared alongside rare photos of Ocasek and the band on their social media outposts. "We will miss him forever, & will forever cherish the precious times we got to work and hang out with him. Rest in Peace & rock on Ric, we love you."
"Feeling grateful for Ric," Flowers told his Twitter followers alongside the aforementioned message. "Had the opportunity to send him this email a couple years back. My first king. Thank you, thank you, thank you."
Ocasek came to fame as a member of the Cars, sharing vocals with late bassist Ben Orr. The act's popular songs include "Shake It Up," "Just What I Needed," "Good Times Roll" and "My Best Friend's Girl," among others. In addition to the Cars, Ocasek enjoyed a career as a solo artist and became an in-demand producer in his post-Cars years. He worked with Bad Brains, Suicide, D Generation, No Doubt, Motion City Soundtrack and oversaw three Weezer albums.
Rockers We've Lost in 2019


text:
Horatio Alger1 was an American writer of novels about impoverished boys rising from humble backgrounds to middle-class security and comfort through hard work, determination, courage and honesty. His writings were characterized by the "rags-to-riches" narrative, which continues to have a formative effect on many entrepreneurs today.
The "rags -to-riches" theme is part of the North American consciousness that helps attract people from around the world to seek their fortunes and success. It is also tied to the idea of free markets as the driver of American pre-eminence globally.
But do we really have free markets anymore? And how does the answer to this question affect your approach to investing in today's markets? Does hard work matter in an era of unlimited money creation by the Federal Reserve and other Central banks?
According to the Horatio Alger mythology, a free market economic system rewards success and punishes those people who fail in the marketplace. The reality today is that with Governments around the globe playing an ever-growing role in their economies, the rewards for personal effort and achievement appears seem to be declining.
When Governments decide which industries to support over others, we end up with "crony capitalism" whereby ties to Government are more important than business viability.
During the recent COVID quarantine in North America, large retail stores and warehouse outlets, were able to continue operating (with Government permission), while their smaller rivals were forced to close until the risks eased. There is no known science to support this treatment of small companies versus larger organizations. None. Yet, large retail organizations were granted privileges that had nothing to do with their business performance.
Recent reports also show that while many private sector employers continue to shed workers (U.S. unemployment applications are at 50+ million people as of early August2), Government hiring is up!
The US Federal Reserve is also (as per many media reports) propping up various sectors with direct cash infusions (airlines and cruise lines) or through direct debt purchases from various companies. This activity is a form of centralized planning where Governments are picking winners and losers in the economy. This type of intervention props up many companies that would otherwise go bankrupt – in effect they are supporting zombie companies, much as Japan and other countries have done in recent years.
Many economists have pointed out that letting companies go bankrupt (creative destruction), is a key feature of capitalism. Yet direct interference by Governments and their proxies, the Central Banks, in the economy indicates that we no longer operate in a completely free market economy.
The implication for investors is to recognize the danger of ONLY buying passive investment vehicles that attempt to replicate the entire economy. This strategy can lead to owning a lot of zombie companies and others of lesser quality. These poor-quality companies are characterized by poor earnings (profit) growth and generally poor business success.
If the North American economy remains weak for some time, there will be distinct advantages to using active portfolio managers (with stock picking skills) who can be nimble and responsive to market and economic moves.
Call us today to discuss how we can position you for investment success in these challenging times!
1https://en.wikipedia.org/wiki/Horatio_Alger. Retrieved on August 17, 2020.
2https://www.forbes.com/sites/jackkelly/2020/07/09/nearly-50-million-americans-have-filed-for-unemployment-heres-whats-really-happening/. Retrieved on August 18, 2020.
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