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Stability of gene contributions and identification of outliers in multivariate analysis of microarray data
BMC Bioinformatics volume 9, Article number: 289 (2008)
Multivariate ordination methods are powerful tools for the exploration of complex data structures present in microarray data. These methods have several advantages compared to common gene-by-gene approaches. However, due to their exploratory nature, multivariate ordination methods do not allow direct statistical testing of the stability of genes.
In this study, we developed a computationally efficient algorithm for: i) the assessment of the significance of gene contributions and ii) the identification of sample outliers in multivariate analysis of microarray data. The approach is based on the use of resampling methods including bootstrapping and jackknifing. A statistical package of R functions was developed. This package includes tools for both inferring the statistical significance of gene contributions and identifying outliers among samples.
The methodology was successfully applied to three published data sets with varying levels of signal intensities. Its relevance was compared with alternative methods. Overall, it proved to be particularly effective for the evaluation of the stability of microarray data.
Ordination methods are useful tools for the analysis of gene expression microarrays. Principal component analysis (PCA) and correspondence analysis (CA) have both been used to extract the main sources of variation present in highly multivariate microarray data [1, 2]. The supervised counterparts of these approaches, including between-group analysis (BGA) [3] and analyses with respect to instrumental variables [4], were proposed to handle descriptive variables controlled in the design of the experiment (e.g. disease classes). When dealing with transcriptomics data, multivariate approaches are generally more appropriate than univariate strategies because they intrinsically take gene covariations and interactions into account.
Constrained ordination methods are very efficient for sample classification and class prediction. They are flexible and can be used easily to identify groups of genes associated with classes of samples. Geometrical interpretations are generally required to investigate the gene-sample relationship. Genes of interest can also be ranked according to their discriminative power. However, considering the exploratory nature of these methods, it is not trivial to assess the significance of a given gene dysregulation in a multivariate setting. These methods rely on solving an eigenvalue problem whose solutions are given by the leading eigenvectors and whose theoretical statistical properties are particularly complex to study. To overcome this issue, resampling techniques have been proposed to estimate the stability of multivariate analyses. These techniques were described in a variety of scientific frameworks including environmetrics [5, 6], chemometrics [7, 8], and archaeology [9]. The general purpose is to develop inferential procedures for testing the statistical significance of the parameters provided by these exploratory techniques. Their applications are manifold, e.g. assessing which variables significantly contribute to the principal axes of a PCA, detecting outliers or influential observations. This approach has a great potential in the context of microarray data analysis as proposed by Tan and collaborators [10, 11]. These authors described an application of bootstrapping to correspondence analysis. They outlined that their approach would have several advantages over classical gene-by-gene fits of ANOVA models. It particularly enables the extraction of lists of genes which are biologically more informative than those found by ANOVA.
In the present work, we propose a specific methodology for testing the stability of constrained ordination methods applied to microarray data. Unlike previous studies, our approach is dedicated to supervised multivariate analyses. To our knowledge, very few studies addressed the issue of stability assessment in supervised multivariate analyses. The potential of associating stability analysis in the supervised multidimensional context is multiple. By using the information of sample descriptors, genes can be associated with a given class of samples and the significance of this association can be assessed. A derived significance testing strategy regarding gene contributions is proposed. Further resampling methods based on jackknifing are also proposed to identify influential observations as an aid in outlier detection in microarray data sets. A comprehensive set of R functions illustrating our methodology was developed. The package is freely available on request.
The present manuscript is organized as follows. The first section introduces some theoretical aspects of ordination methods (with a particular focus on CA) and constrained ordination methods (especially BGA). The subsequent sections describe the different resampling strategies used in this project, as well as details about the algorithm. Illustrative examples demonstrating the implemented technique are given.
Methods and Results
Ordination methods
Both PCA and CA are commonly used in microarray data analysis. Some authors stressed that CA has several advantages over PCA [2, 12]. Like other dimension reduction methods, CA summarizes structures in high-dimension space by projection onto a low dimension sub-space while loosing as little information as possible. Correspondence analysis involves a first step of symmetrical data transformation into a chi-square distance matrix which makes CA outputs particularly appropriate for the exploration of relationships between samples and genes. The mathematical basis of CA has been described elsewhere (see e.g. [13]) and will be briefly summarized. Thereafter observations are shown as rows and variables as columns.
Let us define the following:
Y: the (n × m) matrix of gene expression data (n samples, m genes)
P = Y/N: the data matrix divided by its grand total
r: the n-dim vector of row sums of P
c: the m-dim vector of column sums of P
D r = diag(r): the diagonal matrix of row sums
D c = diag(c): the diagonal matrix of column sums
The correspondence analysis of Y is obtained by carrying out the singular value decomposition of the doubled centered and standardized matrix Z:
with Λ the k × k (k = rank(Z)) diagonal matrix of singular values associated with Z with λ1 ≥ ... ≥ λ k > 0, U an (n × k) matrix whose columns are the left singular vectors of Z and V an (m × k) matrix whose columns are the right singular vectors of Z. The rows of U and V are orthonormal with respect to D r and D c respectively:UTD r U = VTD c V = I
The principal components and row coordinates are respectively given by U and UΛ. The principal axes and column coordinates are respectively given by V and VΛ.
Constrained ordination methods
In microarray experiments, besides the main table Y containing the gene expression values, additional descriptive variables X controlled in the experimental design generally characterize samples. Constrained ordination methods aim to display the variations in the data which are explained by the descriptive variables. These two-table methods are dissymmetric because the information from X is used to constrain the analysis of Y. Correspondence analysis with respect to instrumental variables (CAIV) [4], which is closely related to PCA on instrumental variables [14], and between-group correspondence analysis [3] are two examples of constrained correspondence analysis which have been successfully applied to microarray data. In this field, these methods have been used for different purposes including sample classification [3], disease-class prediction [15], and removal of undesirable effects [4]. BGA is a particular case of CAIV when samples are characterized by one single categorical variable. Between-group correspondence analysis of table Y given the class descriptor x is simply the correspondence analysis of the table Ŷ corresponding to the table of means per group. BGA is the analysis of the per-class centroids. It provides up to g - 1 discriminating axes (g is the number of classes). The initial samples are thereafter projected as supplementary rows in the BGA sub-space. The BGA procedure provides the best linear combination of variables which maximizes the between-group variance.
Stability of gene contributions using bootstrapping
One interesting feature of BGA is the possibility to associate genes with pre-defined sample classes. The gene contribution towards sample classes is defined as the absolute distance from the center of the BGA axes to the orthogonal projections of the gene (y) onto the vector of the class centroid (x) (Figure 1). This distance is measured by the parameter: . The higher |α0| is, the more important the gene contribution is. The sign of α0 indicates whether the gene is specifically up- or down-regulated, respectively for positive and negative values. Genes can be ranked according to their contribution towards each class modalities.
Introduced by Efron [16], bootstrapping is a distribution-free resampling method generally used to estimate the variance of estimators. Like other resampling techniques, bootstrapping provides a good alternative to establish the variability of an estimator. It is classically used to assess the bias and variance of model parameters, construct confidence intervals and rebuild empirical distributions. Several bootstrap refinements were implemented in the framework of techniques incorporating singular value decomposition [17, 18]. In the present work, non-parametric bootstrapping was used to estimate the significance of gene contributions. The proposed bootstrapping strategy is based on the BGA model assumptions. As mentioned previously, the BGA of table Y with regard to the categorical variable x, is the analysis of the (g × m) table Ŷ corresponding to the per-class mean of Y. Let us define X, the (n × g) table of dummy variables coded from x and Ŷ x = X(XTX)-1XTY, the (n × m) matrix of fitted values. Bootstrapped samples are built based on the residuals E = Y - Ŷ x . Residuals are sampled with replacement (E*) and new data sets are built as follow: Y* = Ŷ x + E*.
The analysis of 100 to 1000 perturbated data sets is generally required to assess the parameters' distribution of a multivariate model (in our case, the gene contributions deduced from the gene and class-centroid coordinates). Out of these empirical distributions several indicators of the stability of gene contributions were calculated. Non-parametric 95% bootstrap confidence intervals were constructed using the 2.5% and 97.5% quantiles of the bootstrapped distribution. z-scores were defined for each gene as the ratio of the bootstrap estimates to its standard deviation. p-values were estimated according to the "bootstrapped eigenvector" procedure [6] as the probability of obtaining gene contributions equal to or smaller than zero for genes contributing positively in the original data set, or alternatively equal to or larger than zero for genes contributing negatively in the original data set.
Convex hulls were used to graphically display the spread of the bootstrapped gene coordinates on the dominant principal axes. The relative inertia of these gene coordinates was measured by the ratio of gene inertia to the total inertia.
Lebart [18] proposed two main categories of bootstrapping. Partial bootstrap makes use of a posteriori projections of the resampled elements on the original reference subspace provided by the analysis of the initial data set. Total bootstrap performs a new analysis on each of the resampled data sets. Both strategies have been implemented in the current project. It is noteworthy that partial bootstrap does not involve successive steps of singular value decomposition which makes it considerably faster than total bootstrap. Moreover, because total bootstrap requires a complete CA to be carried out for each bootstrapped table, the new sets of row and column coordinates belong to different subspaces which make their comparison more complex. Unlike partial bootstrap, total bootstrap is potentially subjected to axis reflection or inversion [19]. Signs of row and column coordinates in perturbated data sets can be inverted compared with the original data set. At least two approaches have been reported to overcome this drawback. The first consists in determining the sign of the correlations between the principal axes prior and after perturbations. A negative correlation indicates a reflexion which can be corrected by multiplying the new row and column coordinates by -1. Procrustes rotation was also proposed to fit the resampled row and column coordinates with the original scores and loadings [8, 20, 21]. The first (more conservative) option was implemented in the present work.
Detection of outliers using jackknifing
Jackknifing is another resampling technique introduced by Quenouille [22] and later developed by Tukey [23]. Jackknifed samples are built using a leave-one-sample-out strategy. Although jackknifing can be seen as a rough linear approximation of bootstrapping [16], it proves to be useful for investigating the influence of individual observations, as demonstrated for example in chemometrics by works from Martens and colleagues [7] or Westad and collaborators [8, 21]). In the current paper, jackknifing was used to detect influential samples and outliers in microarray data sets. The number of resampled data sets created by jackknifing equals the number of samples in the original data set. Each new data set is identical to the initial data set except for one sample which is removed.
In a data set including n samples, n consecutive analyses are performed providing n sets of n - 1 sample coordinates. The impact of each individual sample on the other n - 1 samples is measured by the distance from the samples' original positions to their positions after resampling. If a given sample is highly influential, it may importantly impact the position of one or several other samples. A stability plot can be used to visualize the shift in the sample position after jackknifing. A large shift reflects the presence of an influential observation.
In order to identify observations which significantly influenced the position of other observations, the classical multivariate detection of outliers based on the Mahalanobis squared distance (D2) was used. These distances can be evaluated using a χ2 distribution with the appropriate degrees of freedom. Each time a sample removal induced a shift to an extra sample , the 0.975 quantile of a chi-square distribution, with p degrees of freedom, the sample was defined as significantly influential towards the extra sample. Overall, if the median of the n - 1 shifts induced by an observation is greater than a threshold, this observation was declared an outlier.
Similarly to total bootstrap, jackknife outcomes are potentially subjected to axis reflection. Sample coordinates were post multiplied by -1 in case of negative correlation between the principal components prior and after resampling.
Algorithm implementation
The implementation was done using R (with an extensive use of routines from the package ade4 [24]), and a new package multistab including original functions was developed. Our algorithm involves resampling techniques which are computationally intensive. The implementation allows the parallelization of the calculations. The R packages snow and Rmpi allow accessing the MPI/LAM subsystem, an implementation of the MPI standard, for distributing jobs among nodes. Calculations have been performed and tested on different configurations including computers with single and dual core CPUs as well as an MPI cluster of 16 heterogeneous nodes.
Example of application
Data sets
Three publicly available data sets were used to illustrate the different features of our methodology. The first data set consists of a subset of data from the pioneer work of Bhattacharjee and colleagues [25] using gene expression profiling to investigate adenocarcinoma subclasses. The subset used in the current study includes 96 samples classified into 4 groups of patients (38 adenocarcinomas, 21 squamous cell carcinomas, 20 pulmonary carcinoids and 17 normal lung specimens). RNA extracts from tissue specimens (snap-frozen lung tumors and normal lung) were hybridized onto Affymetrix' hgu95a arrays. The second data set was published by Spira and colleagues [26] analyzing the airway epithelial cell transcriptome of smoking patients. In this study, 75 individuals classified into 3 groups (34 current smokers, 18 former smokers and 23 never smokers) were investigated. Bronchial cells were obtained from brushings of the right mainstem bronchus and RNA extracts were hybridized onto Affymetrix' hgu133a arrays. The third data set was described by Baty and colleagues [4] which investigated the effect of beverage consumption in healthy individuals. One hundred and eight samples classified in 5 groups (21 baseline, 20 alcohol, 22 grape juice, 23 water and 22 wine) were analyzed. RNA extracts from peripheral blood leukocytes were hybridized onto Affymetrix' hgu133a arrays. The transcriptomics signal is expected to be high in Bhattacharjee (tumor cells from well-defined lung cancer patients), intermediate in Spira (mixture of bronchial cells in a population of smokers), and low in Baty (physiologic variations of blood cells in healthy patients).
Significance of gene contributions
Five hundred bootstrapped samples were built in order to assess the empirical distribution of the gene contributions within each data set. Partial bootstrap was used and the newly calculated gene coordinates were represented with convex hulls on the factorial map defined by the two first principal axes of the BGA (Figure 2, upper panels). The size of the convex hulls, measured in terms of relative inertia, gives indications about the gene stability. The discriminative power of genes is measured by the distance from the center of the BGA axes to the hull locations. Only the 10 most discriminating genes for each data set are displayed. The degree of hull overlap for the different combinations of factor levels, gives important indication about the specificity of the gene discrimination. The boxplots of gene contributions (Figure 2, lower panels) was used to estimate the proportion of overly unstable genes (genes with a p-value ≥ 0.05). The proportion of overly unstable genes is refered to as false positive rate.
Gene hulls in Bhattacharjee were small (the average relative inertia of the 100 most discriminating genes was 0.01), distant from the center of the plot and the group of genes associated with each factor level did not overlap. This documents the stability and specificity of the markers found in this experiment. This result was further confirmed by the boxplot representation showing the distributions of gene contributions (Figure 2, lower pannels). In Bhattacharjee, all most discriminating genes significantly contributed to the class discrimination since no distribution crossed the 0 threshold (p < 0.002). Thus, the false positive rate was 0%.
On the other hand, in the data sets of Spira and Baty, the relative inertia of gene hulls was larger (the average relative inertia was 0.06 and 0.11 respectively). In the data set of Baty, the degree of hull overlapping was particularly high. The level of false positive rate was moderate in Spira data (8%) and high in Baty data (32%). This level differed from one experimental condition to one another. In Spira, the "Former smoker" group had a higher false positives rate (21%) compared to "Current smoker" (0%) and "Never smoker" (1%). The "Current smoker" category was the one with the most stable gene signals. In Baty, the false positive rate was high. Genes associated with the consumption of water were highly unstable (false positive rate of 70%). Overall the false positive rate was measured for the 100 genes with the highest ranking in terms of gene contribution. As to be expected, this rate increased with lower gene ranks.
Identification of influential observations and outliers
Jackknifing was used to estimate the influence of each observation on the sample coordinates. The stability plots presented in the upper panels of Figure 3 display the sample coordinates (grouped by class) prior and after resampling in the two dominant axes of BGA. The n - 1 positions of each sample were represented with star plots showing the shifts induced by sample removals. In Bhattacharjee data, the relative shifts induced by jackknifing were small (Figure 3, upper left panel). These shifts were much more prominent in Spira and Baty data sets. The barplots in Figure 3 (lower panels) display graphically the degree of influence of each sample. For example, the first sample in Bhattacharjee was found to influence significantly the position of 12 different samples. By comparing the median shift induced by each single sample with a threshold, no sample was declared an outlier in both Bhattacharjee and Spira data sets, whereas 6 samples were found to be outliers in Baty. In Spira, one can easily observe that the influential observations are mostly identified in the patient groups "Former smoker" and "Never smoker". The ouliers in Baty belonged to the "Baseline" and "Wine" group.
Comparison with alternative approaches
The relevance of the results obtained by bootstrapped BGA was compared with those obtained by bootstrapped correspondence analysis [11] and the gene-by-gene fit of 1-way ANOVA models. The 'sarcoidosis' data set provided in our R package was used in this comparative study. This data set, which was previously described [15, 27], included 24 individuals (12 healthy controls vs. 12 sarcoidosis patients). The group of sarcoidosis patients was subdivided into 7 sarcoidosis stage I (low severity) and 5 sarcoidosis stage ≥ II (higher severity) patients. Messenger RNA extracted from peripheral blood were hybridized on Affymetrix' hgu95a arrays. The data were normalized using the 'vsn' algorithm. After gene filtration, 7206 genes remained in the data set. Bootstrapped BGA was performed using 1000 iterations and 84 highly significant genes (p < 0.001) among the genes which mostly participate to the between group discrimination were selected. Hundred and twelve genes with the highest contribution on the first axis in bootstrapped CA were selected. A third list of genes included the 100 most significant genes obtained by ANOVA models. There were 18 genes overlapping between the list from bootstrapped CA and bootstrapped BGA, 27 genes beween bootstrapped BGA and ANOVA and 7 between bootstrapped CA and ANOVA. A functional analysis was carried out on these 3 lists of genes using the web tool DAVID [28]. Table 1 summarizes the 11 significantly enriched Gene Ontology (GO) categories found from the list of genes obtained in bootstrapped BGA. The number of GO categories identified before adjustment for p-values was slightly more diverse in bootstrapped BGA (n = 70) than in bootstrapped CA or ANOVA (respectively n = 52 and n = 55). On the other hand, the enrichment of biologically informative genes in each GO categories was higher in bootstrapped BGA than in bootstrapped CA and ANOVA. This is in agreement with previously reported findings [4, 11].
The advantage of using multivariate versus univariate approaches in highly multivariate data such as microarray data has been already well documented in the literature. The extraction of meaningful gene mechanisms implies that genes are treated as a whole and not separately. This explains why higher enrichment of biologically meaningful GO categories (or functional pathways) are generally obtained when using multivariate approaches compared with univariate approaches. The choice of using unsupervised or supervised ordination methods mainly depends on the objectives of the study. When the biologist is interested in finding groups of discriminating genes that explain differences among well-defined patients categories, BGA is a method which should be considered. Because the grouping information is directly incorporated in the BGA model, the dimension reduction of the multivariate data is driven by the phenotypic information. This generally provides noticeable simplification of data interpretation. In contrast, when using unconstrained CA, one first extracts the major compositional variation present in the leading axes then relates this variation to external information. In certain situations, the leading axes are subject to unexpected sources of variation, making their interpretation difficult.
When the design of experiment tends to become more complex, (e.g. when several controlled variables are included), other multivariate approaches can be used to incorporate this external information into a constrained CA model (see e.g. [4]). Double constrained CA can also be suitable if one wants to incorporate external information on both rows and columns [29]. However, some more complex models of constrained CA including interactions and contrasts might be difficult to interpret. When the number of constraints tends to be too large, a phenomenon of relaxation of constraints may happen. In such cases, simple unconstrained CA might appear appropriate.
The bootstrapping technique presented in this study proved to be very useful to evaluate gene stability in microarray data. The three data sets were chosen with an a priori knowledge about the strength of their transcriptomics signal. The biologically most well-defined data set was Bhattacharjee with four clearly distinct categories of patients and samples taken from distinct types of lung tumors. The class discrimination was high (proportion of explained inertia = 38%; p < 0.001) and the gene signal very stable and specific. A less stable signal came out of Spira data, where samples were derived from a mixture of airway epithelial cells and the patient groups less clear cut. The identification of stable signals specific to "Former smoker" was particularly difficult although the between-class discrimination was significant (proportion of explained variance = 6%; p = 0.006). The weakest and highly unstable signals were found in Baty data, where the expected effect was within the physiological range of normal cells. The proportion of explained variance was very low in this example (4%; p = 0.46).
Jackknifing was particularly efficient to detect influential observations or outliers in our setting. This method provided important diagnostic insights in the data as well as the experimental design. A careful exploration of the sample stability can help the experimenter to identify samples with imprecise or wrong group allocation, or group with a heterogeneous behaviour. Furthermore, this method can be used to identify poorly specified sample categories or subcategories of samples. As an example, further investigations might reveal that the "Former smoker" category in Spira might share gene signatures both from "Never smoker" and "Current smoker". With the proposed tools, researchers can identify inconsistent observations/samples or groups and have a strategy at hand to correct for imprecise descriptions in case of sufficient respective evidence.
Particular attention was paid to the computational aspects of the resampling calculations. The calculations were considerably accelerated by the use of parallelization. Furthermore, routines used to carry out CA and BGA (originally proposed in the R package ade4) have been optimized for the analysis of gene expression data where the number of variables far exceeds the number of samples. Performance testing on data sets of different size showed an improvement of calculation time by a factor 10 to 50. As previously mentioned, the method of partial bootstrap was prefered to total bootstrap for testing the stability of gene contributions since it was simpler to perform and computationally more efficient (approximately twice as fast).
Dimension reduction methods are powerful tools that help biologists exploring their data and generate new hypotheses. Like other supervised approaches, constrained ordination methods incorporate external information that greatly simplifies the interpretation of microarray data analysis. The principal axes of BGA being defined as the linear combination of genes that maximizes the between-group variance, it is straightforward to extract groups of genes that discriminate between disease categories. By using the resampling methodology described above, it is possible to assess the reliability of solutions in a multivariate analysis of gene expression microarray data. Although both bootstrapping and jackknifing should not be used for formal statistical hypothesis testing, they proved to be useful to identify highly consistent genes, filter out some false positive genes, and to allow detection of influential observations among samples. With regard to this complementary information, the biologist can decide to pay more attention to highly stable discriminating genes, which in turn can be used for subsequent formal statistical hypothesis testing. Based on jackknifing information, the biologist can also decide on croping outlying observations or refining a priori sample classification.
In conclusion, the methodology and the collection of tools proposed in this study are suitable for the assessment of the significance of gene contributions and the detection of outliers in microarray data and this in a multivariate fashion. The set of R functions includes additional functions which test the stability of multivariate analysis results. Overall, the R package we developed constitutes a novel and comprehensive suite of diagnostic tools to evaluate the robustness of multivariate representations of high-throughput gene expression data.
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We thank Dr. Olaf Schenk, Prof. Helmar Burkhart, Anita Lerch and Thomas Mangold for their help in high performance computing. We are also thankful to Prof. Stephan Morgenthaler for the fruitful discussions about outlier detection. This work was supported by an unconditional grant from Novartis and an internal research grant.
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FB developed the algorithm, performed the analysis and wrote the paper. DJ and FP contributed to the implementation and the optimization of the algorithm. MMS contributed in the development of the algorithm. MHB supervised the work and was significantly involved in the writing of the manuscript. All co-authors read and approved the manuscript.
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Baty, F., Jaeger, D., Preiswerk, F. et al. Stability of gene contributions and identification of outliers in multivariate analysis of microarray data. BMC Bioinformatics 9, 289 (2008). https://doi.org/10.1186/1471-2105-9-289
DOI: https://doi.org/10.1186/1471-2105-9-289


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It's okay to be more sensitive than you want to be, especially during a horrible health pandemic. I tried being an emotional brick wall when I was younger, but after two major health collapses in my adulthood before I reached my late twenties, I'm way more sensitive about the state of my life than I used to be. I find it harder to deal with certain type of criticism now compared to five years ago, which isn't good, but at least I'm self-aware it's a problem that I need to fix.
We are all negatively impacted by this horrible virus and I feel compelled to rant about how it negatively impacted my plans for 2020. I still have plans for Newgrounds this year, but much of what I intended to do in 2020 will instead be done in 2021 due to the health pandemic negatively impacting my life. My plan at the beginning of last month (March 2020) was to get a local job so I could save up a bunch of money for creative pursuits, but now I can't do that without putting my health at risk. So with less income, it's going to be a lot longer before I can afford things like a printer, scanner, audio interface, instruments, microphones, and other supplies that would benefit my music, art, and graphic design.
I'm optimistic 2020 will still be a good year for me despite how horrible it started off, but this will be a very different year than many of us expected. I'll give occasional progress reports in the future when I have positive things to report about that have nothing to do with the health pandemic. Right now I'm focused on redesigning my bedroom so it functions more like an office than a standard bedroom. I got a roll-up bed just so I can save a ton of space for my future creative pursuits. I don't have a great track record on accomplishing my goals due to how badly my perfectionism killed a lot of projects in my twenties (example: my cancelled Rayman review), but that won't happen this decade. I have learned a ton from my failures. It's better to release something imperfect than to outright cancel projects.
Biggest obstacle I have to deal with is my 24/7 migraine. I have struggled with a 24/7 migraine for over 11 years. It's a lot better this year compared to 2016-2019, but I'm still suffering in chronic pain. I still have days where I do hardly anything besides suffer laying in bed, but at least I'm nowhere near as bedridden as I was in my late twenties. It just amazes me that when my health improved to where I feel like I'm capable of fixing my life, much of the country gets so sick I'm stuck indoors all the time.
I hope I can eventually create content for Newgrounds that is worth enjoying. My primary goal for Newgrounds this decade is to upload music, art, and animation. I bought a license to use Adobe's programs for a year so I have the software to accomplish my goals. I also brought a light table into my bedroom this month to make animating a lot easier. My dad initially got it 25 years ago back when he did photography for living, so it's nice that I'm able to repurpose it for my needs. Here's a few photos of my kitty Little Betty on my light table.
Thank you to everyone who took the time to read all of this. I wish you all the very best in life.
-Willie Corley

subset: commoncrawl


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Do you spend all day working in an office? Do you get back pain? Then a standing desk balance board could be the solution you're looking for.
A lack of movement is bad for our health. This is a well-known fact. But for people that work at a computer, finding a way to get the body moving throughout the working day can be tricky.
If you're already using a standing desk then you're on the right track. Add a balance board and you can take your office set up to the next level.
Why? Because using a balance board means you have to activate your muscles to stay balanced. Especially in the core and lumbopelvic region (where the lower part of the spine meets the pelvic area).
These parts of the body don't get the movement they need by sitting all day, or even standing. However, using a balance board switches them on and the micro-movements help to gently strengthen them.
Plus, it doesn't require a gym and it's a low impact way to exercise the body.
Sounds good? Let's find out more.
How to use a balance board
First things first. What exactly is a balance board?
The clue is in the name. It's an unstable platform that you stand on so you have to work to keep it balanced. The natural movement it promotes then strengthens the body and improves posture.
Here's how it works:
- Choose the type of board you want: wobble (360-degree movement – recommended for standing desks) or rocker (from side to side)
- Stand on the board and get to work with keeping it balanced while getting on with your job
It's as simple as that. Now, let's take a look at five of the best balance boards on the market right now.
Related: Learn more about exercises you can do at your standing desk
Ergohead – Standing Desk Balance Board with Anti-Fatigue Massage Points
No products found.The Ergohead balance board is an ergonomically engineered board. It encourages the ankles to stand in a neutral position to get the maximum benefit of using a standing desk. As a result, it promises a fun and healthy way to work that's safe and accessible for everyone.
This board also has anti-fatigue massage points to keep you going and avoid stiff joints from standing for too long. Plus, it has a fluid rocking motion for low-impact movement.
Want to know if this is the right board for you? Here's the full overview:
- Honeycomb non-slip texture
- Can be used on hard floors and carpet
- Made with EPA certified materials
- 8.5-degree tilting angle
- Weight limit of 440lbs
- Dimension: 19.6 × 13.5 × 2.2 inches
- Portable gel handle
Gaiam Evolve – Rocker Style Balance Board
No products found.Described as a "must have for standing desks", this balance board by Gaiam helps to keep the body active and the mind engaged. This is done by activating muscles in the back, core, legs and ankles and reducing the likelihood of fatigue.
The Gaiam Evolve is a rocker-style balance board to encourage fluid movement in the body and a neutral positioning of the ankles. It's also made with non-slip material, so it's safe for use in the office (both for hard and carpet floors).
Here are the full specs of the Gaiam Evolve:
- Honeycomb non-slip texture
- Ergonomic design
- Weight limit of 250lbs
- For use with any standing desk
- Dimensions: 27 x 12 x 3.65 inches
Matladin – Wobble Board with Wood Construction
No products found.The Matladin standing desk balance board is a blend of anti-fatigue techniques and balance training. This means the movement not only strengthens muscles but also stops the mind and body from getting tired during the day.
To achieve this, the Matladin model has texturized pressure points for the feet made from high-density latex. As well as a PU surface and wooden base to "last for years" and keep the user safe.
Here's the full overview of the Matladin:
- Non-slip, anti-scratch natural rubber base
- Weight limit of 450lbs
- 8.5-degree tilting angle
- Dimensions: 20 x 13.9 x 2.2 inches
- Portable carry handle
Related: Learn how to perform these wobble board exercises to maximize the health benefits of one of these boards.
Nalanda – Wobble Board and Serious Core Trainer
No products found.If you're looking for a more intense workout and a bigger tilt angle, then the balance board by Nalanda could be the one for you.
This is a wobble balance board with a 360-degree rotation and a 24.5-degree tilting angle. As a result, your muscles will work harder and your balancing skills will be challenged. All while getting paid to do your job.
Like the other models, this board has an anti-slip surface for safe balancing with massage pressure points for the feet.
The Nalanda balance board overview:
- Heavy-duty structure finished with TPE
- Weight limit of 660lbs
- Dual handle design for push-up exercises
- Dimensions: 16.34 x 16.34 x 3.9 inches
- Larger size than other models
Fitterfirst – Adjustable Wooden Board with Non-Marking Legs
No products found.For a flexible option, this standing desk balance board by Fitterfirst is worth considering.
Unlike the other models, it comes with fully adjustable foam legs so you can move gently or actively – whatever works for you. Plus, the legs are fitted with Velcro so they can be easily customized and won't slip on the floor.
Another unique detail is the top platform, which is made from Canadian-sourced wood. This makes the Fitterfirst balance board a stylish addition to any office.
The full specs of the Fitterfirst are:
- Non-marking adjustable foam legs
- Dimensions: 24.5 x 12 x 3.25 inches
- Anti-fatigue design
- Rock from side-to-side or front-to-back
- Aimed at balance board beginners
Final thoughts
We all know that spending too much time sitting down is bad for us. It can cause back pain, lead to weakened muscles and even a higher risk of cardiovascular illnesses.
Humans are not supposed to live sedentary lifestyles and introducing movement is a great way to counteract the negative impacts of office work.
A standing desk balance board is more than just a way to get the body moving though. It's also useful for keeping the mind active and reducing fatigue throughout the day.
All of the balance boards in this article are good options. However, for beginners we recommend the Fitterfirst board for the adjustable functionality. But for more advanced balanced board users, the Nalanda model could be the way to go.
There is just one prerequisite. You need a standing desk. If you don't already have one, find out more about how to transform your workspace with our guide to standing desk converters.


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Do you suffer from debilitating back pain? For some people, the pain never seems to go away – it is always lingering. For others, though, the pain seems to come and go with the amount of work you do. The wrong move may cause you to be unable to get through the day. While there is always a need to speak to your doctor, you may also be able to get some relief by updating your home's furniture. Consider, for example, stressless recliners and how they can help you to reduce the strain and stress on your back.
How Do They Work?
The unique design of stressless recliners makes them unique. Because they are designed specifically to reduce pressure, they are able to reduce much of the stress on your back. They offer just enough support to the right areas to accommodate this. For example, you may find there is a bit more support at the lower back, which can help those muscles to relax more so than they would otherwise.
Designed for Comfort
While these recliners can reduce pain, they can also help you to feel comfortable. They do not put strain on those areas but instead help to ease your muscles after a long day. They help to minimize the discomfort you feel within minutes. You may find that they are also an exceptional solution for those who are looking for a way to add a beautiful piece of furniture to the home.
Stressless recliners can be an exceptional investment. The key is to choose those designed for your needs. In many cases, this is all about finding a piece of furniture that is capable of supporting your back, muscles, and joints in the best manner possible. It could help to change your life to invest in furniture like this.


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The PCA Scoop
Weekly Family Update
Week of February 1st, 2021
In This Week's Edition
✦ The Great Kindness Challenge
✦ "Flat Travelers" Project
✦ Virtual Book Fair
✦ February Workshops
✦ Discovery Day: February
✦ CAASPP Prep for FIFTH Graders!
✦ Schoolwide Learner Outcomes
✦ New Intervention Website
✦ Writer's Workshop
✦ Social-Emotional Support: Mindset Mondays
✦ Art Read Aloud by High School Hangouts
✦ High School Hangouts (February)
✦ Annual Black College Expo
✦ Edgenuity Spring Break Update
✦ Scholarship Opportunities
PCA Happenings
The Great Kindness Challenge
"Flat Travelers" Project
Are you looking for a creative way to engage your student? Do you have a Flat Stanley fan in your home? If so, this event is for you!
Join us in learning about new places and the art of writing letters, all while making new friends with this exciting project!
Virtual Book Fair
February Workshops
3rd-5th Grade
Lego Masters Building Challenge: Create a Mode of Transportation!
Click the picture for all the details and to sign up!
Lego Masters Building Challenge: BUILD A CREATURE
Click the picture for all the details and to sign up!
Blubber Experiment
Click the picture for all the details and to sign up!
Crickwing Inspired Art
Click the picture for all the details and to sign up!
Middle School
You had me at "Guten Tag!"
Click the picture for all the details and to sign up!
Discovery Day
Discovery Day is ready to kick off 2021 with more exciting activities! Although it is our hope that some Discovery Day events will be in-person in the future, we remain virtual for the time being.
What is Discovery Day?
- FREE TK-8 educational, interactive, & hands-on virtual workshops led by PCA teachers.
- Opportunity for students to make consistent connections with PCA teachers & peers in their general area.
- Each Discovery Day community offers 4 virtual workshops & 1 class party during January & February.
What will students learn?
Students will experience a new learning theme each month. Check out our Jan/Feb Discovery Day Catalog for more details.
- February: "Food Science" - Enjoy some simple science activities that involve common food items! (See flyer)
How to Register:
We encourage families to register for a Discovery Day community based on your student's grade and nearest location in order to make connections with consistent teachers & peers in your area. However, families may register with another community if that works better for their schedules. Please refer to the Jan/Feb Schedule for a list of communities & mark your calendars.
February Registration
All NEW and RETURNING Discovery Day families who wish to start or continue with us in February need to complete this form for each student. Sign up HERE.
You can expect a teacher from your selected Discovery Day community to email you a Zoom link & list of materials approximately 1 week prior to the workshop and/or 1 day before the workshop. If you have not received a Discovery Day email before the workshop, please check your spam folder first and then contact your HST for assistance. If you register less than 48 hrs before the workshop, you may not receive the Zoom link & information in time. As a result, you can either wait for the next workshop or contact your HST for the information.
We hope to see you soon! Please reach out to your HST if you have questions.
Parent Resources
CAASPP Prep for FIFTH Graders!
Calling All FIFTH Graders!
Join us for weekly, interactive, grade-level videos to help prepare for the CAASPP test this spring. We will be focusing on MATH! So have your student grab a pencil and paper and join one of our math intervention teachers for tips, tricks, and problem solving. Each week will be a different grade, so keep your eyes out for yours!
New Intervention Website
Here is the link to our NEW South Schools Intervention Website:
South Schools Intervention Website
You now have access to our highly anticipated Tier 1 Intervention Programs for Reading to replace our Lively Letters and Sight Words You Can See Videos. In addition to that you will still see our ODI Math Videos, SEL/Growth Mindset Resources, and our Writer's Workshop Video Lessons.
Please remember to update the link in your bookmarks!
Writer's Workshop
Ms. Genieva's Office Hours
Tuesdays: 10-11 and Thursdays: 1-2
https://zoom.us/j/4132267107 Password: davidson
Enrichment Ordering System Update
The Enrichment Ordering System will be down while school is not in session over the President's Day holiday and School Recess, and it will be accessible once again on February 22nd. Our staff, who work hard all year to serve our school, are also on break during this time, and we hope they enjoy their break, as well! We are grateful for your partnership with our school and we hope that you enjoy the holiday break!
Important upcoming Enrichment dates and information can be found here!
Social-Emotional Support
Mindset Monday February Topic: Fostering Friendship & Empathy
Please visit our Mindset Monday Page and check out our newly posted resources for this month's topic: "Fostering Friendship and Empathy".
Then join us on February 8th as we discuss what it means to be a "marble jar friend".
For 6th-12th graders we will also be discussing social anxiety.
When: Monday, February 8th
10am- TK-5th grade, 1pm- 6th-12th grade
Where: ZOOM LINK Password: mindset
High School
High School Hangouts
Art Read Aloud by High School Hangouts
3 amazing high school students collaborated on a read aloud for our younger students for PCA's art month! Check it out!
Story: "Ish" by Peter H. Reynolds
Read by PCA high school students: Amelia S., Bradyn B., and Ruth S.
"Ish" is an inspirational story about how art is about enjoying it and it does not need to be "perfect."
Annual Black College Expo
February 19 & 20 - Annual Black College Expo is Now Virtual! $5 Registration fee
Over 10 million in Scholarships available!
BIG Opportunities:
Get Accepted to colleges on The Spot
College Application Fees Waived
Receive Scholarships on the Spot
Informative Seminars and Workshops
Experts will help you with FAFSA
$1,000 Cash & Prize Giveaways
Career and Internship opportunities ..upload your resume
Edgenuity Spring Break Update
Scholarship Opportunities
Karmen & Rachel
We are your San Diego Family Liaisons.
Please let us know how we can help you!
firstname.lastname@example.com / email@example.com
Website: https://pacificcoastacademy.org
Facebook: https://www.facebook.com/groups/InspireSanDiego/?ref=bookmarks


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Today the U.S. Commodity Futures Trading Commission (the "CFTC") adopted final guidance regarding the cross border application of the new derivatives requirements under the Dodd-Frank Wall Street Reform and Consumer Protection Act ("Dodd Frank"), as well as an interim final exemptive order that phases in the relevant requirements. This adoption was welcome news for market participants, who were facing substantial uncertainty since the CFTC's existing temporary cross border guidance was scheduled to expire today.
The final text of the guidance and the exemptive order is not yet available. However, below are some highlights of the guidance and the exemptive order for funds and investment advisers, based on the discussion at the CFTC meeting and the materials released so far:
- Parties can continue to rely on the existing temporary cross border guidance (the CFTC order effective December 21, 2012) until 75 days after the final guidance is published in the Federal Register.
- Under the temporary cross border guidance, a collective investment vehicle is only a "US person" if it is organized in the United States. Under the final guidance, a collective investment vehicle will also be a "US person" if (i) a majority of its interests are owned by US persons (unless interests in the fund are publicly offered, but are not offered in the United States); or (ii) the fund's principal place of business is in the United States. The test for determining the location of a fund's principal place of business will depend principally on the location of the fund's investment managers, fund sponsors and promoters, and the sales and trading desk used by the fund. As a result of this expanded definition, many transactions between offshore funds advised by US investment advisers and non-US swap dealers will become subject to the Dodd-Frank requirements.
- US swap dealers will be required to comply with the Dodd-Frank transaction-level requirements (such as clearing, margin, swap execution facility trading, real-time reporting and external business conduct standards) with respect to transactions with all counterparties.
- Non-US branches of US swap dealers will also be required to comply with these requirements, but with respect to transactions with non-US persons, can generally satisfy the requirements through "substituted compliance" (compliance with the comparable requirements of another jurisdiction) if the transaction has a "bona fide" connection to the non-US branch. The CFTC will determine whether a particular category of requirements of another jurisdiction are comparable to the Dodd-Frank requirements, using an "outcomes-based approach." The CFTC issued a no-action letter yesterday indicating that certain risk mitigation requirements of the European Market Infrastructure Regulation (EMIR) (confirmation, portfolio compression, portfolio risk valuation, and portfolio compression requirements) are "substantially identical" to the Dodd-Frank requirements.
- Non-US swap dealers will be required to comply with the transaction-level requirements with respect to transactions with US persons and with non-US affiliates guaranteed by a US person, but will be able to satisfy the requirements with respect to transactions with non-US affiliates guaranteed by a US person through "substituted compliance."
- The Dodd-Frank requirements are generally becoming effective earlier than the corresponding requirements in other jurisdictions. Therefore, in order to provide time for comparable requirements in other jurisdictions to become effective, a non-US swap dealer or non-US branch of a US swap dealer located in Australia, Canada, the European Union, Hong Kong, Japan or Switzerland only needs to comply with the requirements in effect in its jurisdiction for any requirement for which "substituted compliance" is possible until the earlier of (i) December 21, 2013, or (ii) 30 days following the issuance of a substituted compliance determination for the relevant requirement.
Please contact the Ropes & Gray attorney who usually advises you with any questions.
Stay Up To Date with Ropes & Gray
Ropes & Gray attorneys provide timely analysis on legal developments, court decisions and changes in legislation and regulations.
Stay in the loop with all things Ropes & Gray, and find out more about our people, culture, initiatives and everything that's happening.
We regularly notify our clients and contacts of significant legal developments, news, webinars and teleconferences that affect their industries.


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FlowerPot: A quick and easy way to set up Amiga OS4.1FE on WinUAE by the makers of Amikit
The makers of Amikit, an amazing emulated pre-built environment, has released FlowerPot, a set of tools to automate setting up OS4.1FE in the latest and greatest version of WinUAE, without some of the limitations we ran into in 2015 and 2016 (like only being able to use PicassoIV emulation and not higher-RAM UAE graphics, pci bridgeboard support, etc).
It's not free, but it's not expensive either. I'm currently testing it and will have a review later.
Go check it out –> here <–


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A Los Angeles court denied Britney Spears' request to eject her father from a guardianship arrangement that gives him control of her affairs, US media reported on Thursday.
The decision comes a week after the singer made an impassioned plea to end the "abusive" conservatorship during which she said she has been medicated to control her behavior, prohibited from making decisions on friendships or finances, and prevented from having a contraceptive implant removed, despite wanting more children.
The Los Angeles Superior Court ruling made on Wednesday was in connection to a request filed in September by Spears' lawyer to add wealth management firm Bessemer Trust to the conservatorship and remove her father Jamie Spears, CNN reported.
-The conservator's request to suspend James P. Spears immediately upon the appointment of Bessemer Trust Company of California as sole conservator of estate is denied without prejudice- Judge Brenda Penny said in court filings seen by CNN.
The decision did not take Spears' statement from last week into consideration.
Spears' father has asked the court to investigate the music superstar's allegations that she was medicated with lithium and made to perform against her will, CNN reported.
The revelation that the conservatorship is preventing her from removing a contraceptive IUD sparked outrage from fans and reproductive rights groups online.
Spears' emotional address by videolink was a rare insight into her personal life after her lawyer Samuel Ingham said in April that Spears wanted to directly address the court.
-I just want my life back. It's been 13 years and it's enough- Spears said in the 20-minute statement.
The 39-year-old star's finances and personal life have been largely managed by Jamie Spears since her highly public breakdown more than a decade ago, leading some adoring fans to launch a "FreeBritney" online campaign in recent years.
Supporters have long scoured her social media accounts for hints about her well-being, and any sign that she may be eager to throw off the guardianship.


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WINDSOR, Ont.— The Online Revealed Conference attracted more than 200 attendees to Caesars Windsor Hotel & Casino in Windsor, Ont. last week to hear the latest trends in digital marketing innovation and best practices for marketing tourism and travel online.
Over the course of three days days, attendees had the opportunity to hear from industry leaders including Facebook, Google, Expedia and LinkedIn with keynotes from Hair Nari, VP North America for Expedia and Mitch Joel, president of Twist Image.
Expedia's Nari pointed out that Canada is doing better post recession than U.S. "The RevPar was $78.8 in 2012 and it has been the best it's been since pre-recession levels, while the U.S. is not at pre-recession levels just yet".
Multiple workshops focusing on subjects ranging from SEO for hotels to Facebook marketing ROI, blogging, Pinterest for hotels and tools needed for measurement strategies provided attendees hands-on education learning opportunities.
Most experts at the conference agreed that when it came to travel marketing online, content was king. Hotel operators need to optimize content on their online properties by utilizing a mix of tools, such as photos, reviews, blogs and social media that's right for them. In addition, mobile was picked as the fastest growing trend with Expedia's Nair pointing out that "You don't want to just look into mobile, you want to invest into mobile".
The conference wrapped up with the presentation of The Canadian e-Tourism Awards luncheon hosted by the Canadian Tourism Commission. Winners were selected from more than 45 entries internationally. Best Western was awarded first place for best online campaign, New Brunswick Tourism was awarded first place for best website, Newfoundland and Labrador Tourism was awarded for best user generated content and Tourism Vancouver won first place for best innovative use of technology.
Visit @Hoteliermag on Twitter for all the insight from the conference.


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Manchester United remain unbeaten in 10 Premier League games with Ole Gunnar Solskjaer in charge.
The Norwegian has rejuvenated the team after a terrible start the season under José Mourinho.
United have only dropped 4 points in the league since Solskjaer's arrival in mid-December, a record that has put them in a strong position to qualify for next season's UEFA Champions League.
READ MORE: Man Utd linked to 22 goal, 11 assist playmaker ready to make step up from Primeira Liga
Solskjaer (26) has overtaken former Chelsea boss Guus Hiddink (25) for the most points won by a manger in their first 10 games.
*26 points
— StrettyNews.com (@StrettyNews) February 25, 2019
With his Premier League record resting at 8 wins and 2 draws, Solskjaer has become the quickest manager in the league's history to secure 26 points. He could add a further three points to his tally on Wednesday night when United face Crystal Palace at Selhurst Park.
The Reds slipped back to fifth following Sunday's scoreless draw, while Arsenal jumped to fourth after beating Southampton. Chelsea, in sixth, were busy in the League Cup final, losing to Manchester City on penalties.


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Oral sex is one of the ways married couples, escorts and other individuals enjoy sex. When done right, it can be an unforgettable experience to both of you and hence worth a try. However, there are some fundamental tips which helps oral sex to be fun. They include:
Using your mouth and your hands too
If your tongue or mouth is tried, you can switch to using your hands slowly to relax and gain strength. Alternatively, you can stimulate her clitoris with your tongue while still fingering her slowly or touching other sensitive areas to make it more enjoyable. On the other hand, a woman can slowly lick the tip of the penis while directing it into her mouth using her hands. In fact, it helps women prevent deep throats where men get carried away and want a full penis sensation in their mouth. You can wrap the bottom of his shaft with your hands and then take the rest of his shaft into your mouth slowly.
You can use a lube
If you don't like the smell of the genital area, there are flavored and scented lubes which can help you with that. Lube can also add an extra sensation to a hand job making it more enjoyable.
Choose the right oral positions
When having oral sex, easy access to each other's genitals is key to facilitate stimulation. This can be achieved through a lot of practice and performing some online research prior to having oral sex. Here are common examples of oral sex positions:
• The classic – This can be applicable to both men and women depending on who lies on the bed. To a woman, you can modify this style by placing a pillow under the hips of the woman to raise her pelvis for better stimulation.
• Queening – This is mostly used to satisfy women. Here, the woman sits on the face of her lover for oral sex. It can be done when a man lies flat on the bed and a woman kneels over him. Since it is possible to move your hips while still being aroused, queening is very effective in adult oral sex.
• The throne – this is the opposite of queening. Here a man sits on a chair while the woman kneels before him giving oral sex. This is great for couples who like to watch a bit of porn during their oral encounter.
• Doggy style – This is also ideal to please women especially during oral sex. The man can be laying on the bed to have a good view of your genitals or he can be behind you.
• Standing up – as a man, you can stand up and have a woman sit on a chair, bed or kneel while giving you a blow job. The woman can also use her hands to stimulate other erotic parts of the man simultaneously.
Even though oral sex is enjoyable, a man and a woman should agree on it before embarking. This makes it more fun and everyone contributes without shying off or failing to do their part. Additionally, you can agree on do's and don'ts to make it inclusive. For example, if you don't like tasting semen, you can agree not to ejaculate in the mouth of your lover. Otherwise, oral sex is fun for all involved!
Visit charlotte escorts for more info.


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PooIt's likely that you have come across Karatbars through an email list, on social media or got it recommended by a friend or family member.
Is Karatbars a pyramid scheme? Is it worth investing in this business opportunity or is it another overhyped scam?
First and foremost I must commend you for actually doing a bit of extra research before committing to purchasing or joining Karatbars. For all you could have known, Karatbars may very well be a scam and rob you of your money so this review could help you find anything peculiar about it.
To be totally transparent with you I haven't used Karatbars so I can assure you that I will not attempt to sell you on it unless of course it's worth investing in.
What I will aim to do is provide you with an unbiased 3rd party review of Karatbars that will hopefully help you to make the correct decision in the end.
PRODUCT NAME: Karatbars
OWNER/S: Harald Seiz
TYPE OF PRODUCT: Gold investment MLM
SUMMARY: Karatbars is a legitimate MLM company and isn't a scam or a pyramid scheme as far as I can tell however, besides it's nice packaging for the gold, that's also authentic gold, there's not many things about it that make Karatbars worth joining.
The need to constantly recruit, the accusations of it being a fraudulent company by Canada and Netherlands, the overpriced products and the lack of transparency regarding the earnings of its distributors are all sign that just don't make becoming a Karatbars distributor all that appealing to me.
Because of the reasons mentioned above, I recommend that you skip this business opportunity.
Table of Contents
Karatbars is a gold investment MLM founded by Harald Seiz in 2011.
Although the primary thing that they sell is gold for the most part, the company deals with other precious metals as well. The headquarters is currently located in Stuggart, Germany and in terms of it's growth, Karatbars is present in over 70 countries and has the ambition to expand into 194 countries in total.
So its definitely a business with a vision anyways, let's move on to the product line on offer.
==>Click Here To Access My FREE Make Money Online Guide!<==
Karatbars mainline of products are obviously gold as the name of the company would suggest and the variations that the gold comes in are dependant on how pure you want the it to be. They can vary from 24 ct upto 999.9 for pure gold Atakulche bars.
One thing that makes Karatbars gold more appealing is that the amount you can purchase is quite flexible. If you want to, you can purchase a small amount of 1 gram or as large as 30 grams. Along with the varied amounts, the packaging is also quite unique.
Each piece of packaged gold contains the assayer's signature an stamped with a valid seal. It's also essentially pressed into the shape of a credit card which is protected by UV film to add the finishing touches. The back of the gold also has a holographic acorn like design which is both a security measure and makes the gold look a little more appealing.
As for the prices that you'll be needing to pay, to purchase 1 gram will cost you around $ 67 which is nearly twice the price of market value gold.
So basically what you're doing is paying an extra 30 bucks for the credit card design. This definitely doesn't seem worth your money especially if the only reason your purchasing the gold is for the value it will have in the future.
As is the case with pretty much all MLM businesses there are 2 ways to make money with them, Karatbars being no exception.
1. The first method is by directly selling the product to other individuals and in return make a commission for the sales
2. You make money through your recruits and downline, by getting residual income by following and meeting certain criteria as well as make money through bonuses and incentives due to meeting company set goals.
If you want get started with Karatbars and officially become a distributor for them, you will need to purchase one of their 3 starter kits although, if you just want to become a member it's actually free.
The packages themselves aren't actually called starter kits but, I'll just call them that anyways. As for what's on offer, there are 3 main ones :
- Bronze Package – $135
- Silver Package – $350
- Gold Package – $800
There is also a VIP package where you'll actually be looking to pay $2100 but, it also does provide the best commission rates and I guess, value for money if you're serious about joining the company.
Either way, to get started with Karatbars you will, at the very least, need to spend $135 so it's far from having the most expensive of start up costs that I've seen. Nevertheless, your up line will probably suggest that you buy one of the more expensive packages because they'll benefit from it too so do be aware of this.
Karatbars compensation plan is pretty long and complicated but it's also essential that you actually learn it because without it, you won't understand how to make money as a Karatbars distributor. The structure that they use for their plan is a binary structure, a pretty common structure in the MLM industry.
Anyways I'll try to break it down for you briefly :
- Direct Commissions : You can earn up to 20% in direct sales depending on which level of package you decide to purchase.
- Unilevel Generational Bonus : Depending on your rank within the company you can earn anywhere from 0.5% – 6% in commissions from the total of all the products sold within your downline.
- Package Bonus : You'll earn a set bonus for any package you mange to sell for the bronze, silver, gold or vip packages. You can earn up to 20% in commission for each package you manage to sell.
- Dual Team Bonus : This one's a little confusing but from what I've gathered you basically get paid out on 2 different amounts depending on how well each of you downline legs do.
- Worldwide Turnover Bonus : I couldn't quite understand this one either but, it seem that for every gram of gold sold, $0.95 goes in to a worldwide pool that eventually gets distributed amongst qualified affiliates. Don't hold me to this because I'm still a little confused trying to understand it.
- Gold Pool : This is where 1% of all the lump sum that's generated by the sale of the gold goes. This is later divided amongst some of the qualified distributors.
As I said the plan is very complicated so you probably will need to go over it quite a few times just to understand what's going on. You can check out the plan by clicking here on just check out the video below.
Recruitment Is Pretty Much Essential To Succeed
You will need to know how to recruit and even know how to sell face to face if you want to be able to succeed with Karatbars.
The generational unilevel bonus and the dual team bonus both show how the larger your team is the better chance you have in making more sales and in turn the larger your paycheck will be in the end of the month.
The thing is, you probably need to atleast recruit 2 members, within your left and your right legs in order to actually gain full access to the compensation plan and if right now you're thinking of asking family members or friends to recruit into your team, I suggest you don't.
The reason why is because if they join and are essentially failing, they'll probably blame you for roping them in and wasting their time and money. It's quite possible that by getting them involved, you could really strain you relationships with them if everything goes south for them which is why you should look elsewhere when it comes to recruitment.
Of course it's not that easy to get strangers to join right? If you don't have the slightest idea on how to recruit people or even sell the gold to random people, you'll probably struggle quite a lot.
This means you've either got to dedicate a lot of your resources trying to figure out how to recruit, whether it be through online methods or networking events. That's why unless you already have the skill set in place or if you're really willing to put in the work to make it work, I'd suggest you look elsewhere.
The Compensation Plan Is Very Complicated
I tried to breakdown the compensation plan as best as I could but, the plan still isn't a very easy text to understand. This is a pretty big deal considering you will need to know how the money system actually works just so you don't get done over by companies incompetence in paying you.
It's not the worst thing about Karatbars but, it definitely is massive annoyance trying to learn it back to front.
It's Been Regarded As A Fraudulent Company In Some Countries
Some countries have outlined Karatbars as being a fraudulent company. Authorities such as Canada Scam detecting company called Autorité des marchés financiers (AMF) and similar authorities in the Netherlands have put Karatbars under fire for being a potential scam and ponzi scheme.
Of course it's not yet been called out as a pyramid scheme but, it's definitely worth being a bit wary about Karatbars business operations if you do decide to join them.
The Price Of Gold Is Almost 2 Times Market Value!
To purchase 1 gram of gold within Karatbars will cost you $67 but, if you just bought it at the normal market price, at the writing of this review, 1 gram of gold actually will cost you a little as $41.
This means that Karatbars is essentially charging you an extra $26 just for the over the top packaging. Although gold is valuable, it definitely isn't worth spending this much extra on it that's for sure.
If you still want to buy gold, you'll be better off just buying it at market value and not from Karatbars
Lack Of Transparency
Karatbars aren't very transparent with their income disclosure statements because I couldn't find them however, I doubt it's a very fruitful endeavour to pursue anyways.
Going off what I've seen in other income disclosure statements from MLM's like Xyngular, Avon, Max International, Ariix and Jeunesse, the likelihood of making any decent money is actually pretty limited.
In pretty much all of these MLM's, it seems that only the top 5% are making anything half decent at $1k/month and around the top 1% are making a full time income.
Although there isn't any concrete proof that this is exactly the case with Karatbars, I honestly doubt that it's anything too far off.
So do keep this point in mind if you're considering becoming a Karatbars distributor.
The Gold Being Sold Is Actually Real Gold
So if you're concerned about the quality and the authenticity of the products in question, you don't need to be because it actually is real gold. Nevertheless, it's still way to expensive and I wouldn't recommend you buy any but, it's real so the product itself isn't a scam.
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As far as I can tell, it doesn't seem like Karatbars is a pyramid scheme or a scam. In fact you can say that this MLM company is legitimate.
However, besides the authentic gold that they sell, the rest of what's offered by the company just doesn't make it a very appealing business opportunity, in my opinion, to pursue.
The need to constantly recruit, the accusations of it being a fraudulent company by Canada and Netherlands, the overpriced products and the lack of transparency regarding the earnings of its distributors are all signs that just don't make becoming a Karatbars distributor all that appealing to me.
Maybe the packaging is good too but, unless you really want to become a distributor for some reason, I recommend you skip this MLM company.
I personally will always recommend against using a MLM business model to make money, not because you can't make money through it (you totally can) but, the system has always seemed shady to myself and is kinda synonymous with the likes of a pyramid scheme or scams (MOBE and Digital altitude).
Instead I prefer working with something created through ones own means and is ultimately dependent on yourself and your work ethic alone.
This method I'm talking about is affiliate marketing.
The reasons as to why I recommend it over MLM based structures are because
– there is no need to recruit constantly
– it is a legitimate method that has been working consistently and continues to grow as more businesses want individuals to promote products
– and because it is free to start up, no unnecessarily large start up funds needed.
The service I recommend is Wealthy Affiliate. It's free to sign up to and will get you set up and ready to start your affiliate marketing journey within minutes, as it did for me when I begun my journey.
If you have any questions that you would like to ask me regarding Karatbars, feel free to do so in the comments section below and will I get back to you as soon as I can. If you have your own thoughts about Karatbars and would like to talk about it, again feel free to do so in the comments below!


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Greg Zerkel spent his formative years in MD, his college years in VA and his professional career in NY, PA and WV prior to retiring to the Lowcountry.
Zerkel owned and operated a large land services company which specialized in the acquisition of land and legal rights in the oil and gas exploration space. Zerkel served for many years on the board of the American Association of Professional Landmen.
Having always owned long haired dachshunds in his youth and golden retrievers in his adult life, Zerkel brings a true passion and love of animals to the Hallie Hill board.
Zerkel also volunteers his time and energy on feeding the needy, swim lessons for underprivileged youth, and various church related responsibilities. He is an active member of St John's Parrish.


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Here's the difference between Google BigQuery and Databricks. The comparison is based on pricing, deployment, business model, and other important factors.
BigQuery is a fully-managed, serverless data warehouse that enables scalable analysis over petabytes of data. It is a Platform as a Service that supports querying using ANSI SQL. It also has built-in machine learning capabilities. BigQuery was announced in May 2010 and made generally available in November 2011.
Databricks provides a data lakehouse that unifies your data warehousing and AI use cases on a single platform. With Databricks, you can implement a common approach to data governance across all data types and assets, and execute all of your workloads across data engineering, data warehousing, data streaming, data science, and machine learning on a single copy of the data. Built on open source and open standards, with hundreds of active partnerships, Databricks easily integrates with your modern data stack. Additionally, Databricks uses an open standards approach to data sharing to eliminate ecosystem restrictions. Finally, Databricks provides a consistent data platform across clouds to reduce the friction of multicloud environments. Today, Databricks has over 7000 customers, including Amgen, Walmart, Disney, HSBC, Shell, Grab, and Instacart.
Overview | ||
Categories | Data Warehouses | Data Warehouses, Data Lakes |
Stage | Late Stage | Late Stage |
Target Segment | Enterprise, Mid size | Enterprise, Mid size |
Deployment | SaaS | SaaS |
Business Model | Commercial | Commercial |
Pricing | Contact Sales | Freemium, Contact Sales |
Location | US | San Francisco, US |
Companies using it | ||
Contact info |


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