scholarly journals Stimulus Onset Hub: An open-source, low latency, and opto-isolated trigger box for neuroscientific research replicability and beyond

2019 ◽  
Author(s):  
Charles E. Davis ◽  
Jacob G. Martin ◽  
Simon J. Thorpe
Keyword(s):  
Open Source ◽  
Low Cost ◽  
Eye Gaze ◽  
Stimulus Onset ◽  
Small Sample ◽  
Manual Response ◽  
Replication Crisis ◽  
Stimulus Timing ◽  
Small Sample Sizes ◽  
Almost All

There is currently a replication crisis in many fields of neuroscience and psychology, with some estimates claiming up to 64% of research in psychological science is not reproducible. Three common culprits which have been suspected to cause the failure to replicate such studies are small sample sizes, “hypothesizing after the results are known,” and “p-hacking.” Here, we introduce accurate stimulus timing as an additional possibility. Accurate stimulus onset timing is critical to almost all psychophysical research. Auditory, visual, or manual response time stimulus onsets are typically sent through wires to various machines that record data such as: eye gaze positions, electroencephalography, stereo electroencephalography, and electrocorticography. These stimulus onsets are collated and analyzed according to experimental condition. If there is variability in the temporal accuracy of the delivery of these onsets to external systems, the quality of the resulting data and scientific analyses will degrade. Here, we describe an approximately $200 Arduino based system and associated open-source codebase which achieved a 5.34 microsecond delay from the inputs to the outputs while electrically opto-isolating the connected external systems. Using an oscilloscope, the device is configurable for different environmental conditions particular to each laboratory (e.g. light sensor type, screen type, speaker type, stimulus type, temperature, etc). This low-cost open-source project delivered electrically isolated stimulus onset Transistor-Transistor Logic triggers with a median precision of 5.34 microseconds and was successfully tested with 7 different external systems that record eye and neurological data.

Impaired List Learning Is Not a General Property of Frontal Lesions

2009 ◽  
Vol 21 (7) ◽  
pp. 1422-1434 ◽  
Author(s):  
Michael P. Alexander ◽  
Donald Stuss ◽  
Susan Gillingham
Keyword(s):  
General Property ◽  
Memory Performance ◽  
Small Sample ◽  
Group Differences ◽  
Task Structure ◽  
Significant Group ◽  
List Learning ◽  
Small Sample Sizes ◽  
Almost All ◽  
Frontal Lesions

Background: List-learning tasks are frequently used to provide measures of “executive functions” that are believed necessary for successful memory performance. Small sample sizes, confounding anomia, and incomplete representation of all frontal regions have prevented consistent demonstration of distinct regional frontal effects on this task. Objective: To confirm specific effects of lesions in different frontal regions. Subjects: Forty-one patients with chronic focal frontal lesions and 38 control subjects. There were no group differences in naming scores. Methods: Two word lists were presented, one with unblocked words from related categories and one in a preblocked format. Standard measures of learning, recall, recognition, and strategies were obtained, first for the frontal group as a whole and then for large but defined frontal regions. For all measures with significant group differences, a lesion “hotspotting” method identified possible specific regional injury effects. Results: The frontal group was impaired on almost all measures, but impairments on most measures were particularly identified with lesions in the left superior frontal lobe (approximately area 9s) and some deficits in learning processes were surprisingly more prominent on the blocked list. Conclusion: Difficulty with list learning is not a general property of all frontal lesions. Lesions in different frontal regions impair list learning through specific mechanisms, and these effects may be modified by manipulations of the task structure.

scholarly journals The Current Role of Induced Endometrial Trauma (Endometrial Scratch) in Women Undergoing Infertility Treatment

2021 ◽  
Author(s):  
Mostafa Metwally ◽  
Stephen Walters ◽  
Robin Chatters
Keyword(s):  
Low Cost ◽  
Small Sample ◽  
Pregnancy Rates ◽  
Mechanical Trauma ◽  
Fertility Treatments ◽  
Current State ◽  
Randomized Controlled Studies ◽  
Endometrial Scratch ◽  
Small Sample Sizes

AbstractInduced endometrial trauma, otherwise known as endometrial scratch is a simple technique that has been rapidly adopted into clinical practice, mainly for women having IVF treatment, in an attempt to increase pregnancy rates. The introduction of endometrial scratch followed early reports of improved clinical pregnancy rates in women with repetitive implantation failure after having the procedure and follows on from evidence from animal models in the early 20th century suggesting that mechanical trauma to the endometrium can induce decidual changes. Due to the ease and low cost of the procedure, it has been rapidly adopted as an add-on to fertility treatments, in many cases where evidence is still lacking. Despite the initial publication of a large number of studies that demonstrated encouraging improvements in pregnancy rates in women who underwent this procedure, these studies were mainly limited by the small sample sizes and heterogeneity of their study populations, leading to limited validity of the evidence provided by these studies. More recently, three large randomized controlled studies have been published that paint a different picture regarding the value of this procedure. This article explores the evolution of the evidence and the current state of endometrial scratch as an adjuvant therapy for women undergoing IVF treatment.

scholarly journals The Effectiveness of Combining Visual Art Activities and Physical Exercise for Older Adults on Well-Being or Quality of Life and Mood: A Scoping Review

2017 ◽  
Vol 38 (12) ◽  
pp. 1784-1804 ◽  
Author(s):  
Roswiyani Roswiyani ◽  
Linda Kwakkenbos ◽  
Jan Spijker ◽  
Cilia L.M. Witteman
Keyword(s):  
Quality Of Life ◽  
Older Adults ◽  
Physical Exercise ◽  
Visual Art ◽  
Low Cost ◽  
Well Being ◽  
Small Sample ◽  
Art Activities ◽  
Small Sample Sizes

Visual art activities and physical exercise are both low-intensity and low-cost interventions. The present study aims to comprehensively describe published literature on the effectiveness of a combination of these interventions on well-being or quality of life (QoL) and mood of older adults. Embase, CINAHL, Ovid Medline (R), PsycINFO, and Web of Science databases were searched for studies published between 1990 and 2015 that evaluated interventions combining visual art therapy and exercise for people aged 50 years or older with at least one resultant well-being or QoL or mood outcome. We found 10 studies utilizing different combination programs and outcome measures, and most had small sample sizes. Seventy percent of the studies reported that combining both interventions was effective in improving well-being or QoL and mood in older adults. Future studies are, however, requisite to investigate whether in the respective population such a combination is more effective than either of the interventions alone.

Statistics for Small Groups: The Power of the Pretest

1988 ◽  
Vol 13 (3) ◽  
pp. 142-146 ◽  
Author(s):  
David A. Cole
Keyword(s):  
Statistical Power ◽  
Change Score ◽  
Small Sample ◽  
Analysis Of Covariance ◽  
Small Samples ◽  
Group Differences ◽  
Control Group ◽  
Small Sample Sizes ◽  
Almost All ◽  
Treatment Control Group

In the area of severe-profound retardation, researchers are faced with small sample sizes. The question of statistical power is critical. In this article, three commonly used tests for treatment-control group differences are compared with respect to their relative power: the posttest-only approach, the change-score approach, and an analysis of covariance (ANCOVA) approach. In almost all cases, the ANCOVA approach is the more powerful than the other two, even when very small samples are involved. Finally, a fourth approach involving ANCOVA plus alternate rank assignments is examined and found to be superior even to the ANCOVA approach, especially in small sample cases. Use of slightly more sophisticated statistics in small sample research is recommended.

scholarly journals What Do We Know about The Use of Virtual Reality in the Rehabilitation Field? A Brief Overview

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1042
Author(s):  
Antonino Naro ◽  
Rocco Salvatore Calabrò
Keyword(s):  
Virtual Reality ◽  
Low Cost ◽  
Assessment Method ◽  
Small Sample ◽  
Cognitive Domains ◽  
Rehabilitation Outcomes ◽  
The Past ◽  
Pros And Cons ◽  
Small Sample Sizes ◽  
Near Future

Over the past two decades, virtual reality technology (VRT)-based rehabilitation has been increasingly examined and applied to assist patient recovery in the physical and cognitive domains. The advantages of the use of VRT in the neurorehabilitation field consist of the possibility of training an impaired function as a way to stimulate neuron reorganization (to maximize motor learning and neuroplasticity) and restoring and regaining functions and abilities by interacting with a safe and nonthreatening yet realistic virtual reality environment (VRE). Furthermore, VREs can be tailored to patient needs and provide personalized feedback on performance. VREs may also support cognitive training and increases patient motivation and enjoyment. Despite these potential advantages, there are inconclusive data about the usefulness of VRT in neurorehabilitation settings, and some issues on feasibility and safety remain to be ascertained for some neurological populations. The present brief overview aims to summarize the available literature on VRT applications in neurorehabilitation settings, along with discussing the pros and cons of VR and introducing the practical issues for research. The available studies on VRT for rehabilitation purposes over the past two decades have been mostly preliminary and feature small sample sizes. Furthermore, the studies dealing with VRT as an assessment method are more numerous than those harnessing VRT as a training method; however, the reviewed studies show the great potential of VRT in rehabilitation. A broad application of VRT is foreseeable in the near future due to the increasing availability of low-cost VR devices and the possibility of personalizing VR settings and the use of VR at home, thus actively contributing to reducing healthcare costs and improving rehabilitation outcomes.

scholarly journals Characterizing the Urban Mine—Simulation-Based Optimization of Sampling Approaches for Built-in Batteries in WEEE

Recycling ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 19
Author(s):  
Paul Martin Mählitz ◽  
Nathalie Korf ◽  
Kristine Sperlich ◽  
Olivier Münch ◽  
Matthias Rösslein ◽  
...  
Keyword(s):  
Small Sample ◽  
Data Sets ◽  
Distributed Data ◽  
Sample Sizes ◽  
Representative Sampling ◽  
Comprehensive Knowledge ◽  
Simulation Based ◽  
Using Data ◽  
Small Sample Sizes ◽  
Almost All

Comprehensive knowledge of built-in batteries in waste electrical and electronic equipment (WEEE) is required for sound and save WEEE management. However, representative sampling is challenging due to the constantly changing composition of WEEE flows and battery systems. Necessary knowledge, such as methodologically uniform procedures and recommendations for the determination of minimum sample sizes (MSS) for representative results, is missing. The direct consequences are increased sampling efforts, lack of quality-assured data, gaps in the monitoring of battery losses in complementary flows, and impeded quality control of depollution during WEEE treatment. In this study, we provide detailed data sets on built-in batteries in WEEE and propose a non-parametric approach (NPA) to determine MSS. For the pilot dataset, more than 23 Mg WEEE (6500 devices) were sampled, examined for built-in batteries, and classified according to product-specific keys (UNUkeys and BATTkeys). The results show that 21% of the devices had battery compartments, distributed over almost all UNUkeys considered and that only about every third battery was removed prior to treatment. Moreover, the characterization of battery masses (BM) and battery mass shares (BMS) using descriptive statistical analysis showed that neither product- nor battery-specific characteristics are given and that the assumption of (log-)normally distributed data is not generally applicable. Consequently, parametric approaches (PA) to determine the MSS for representative sampling are prone to be biased. The presented NPA for MSS using data-driven simulation (bootstrapping) shows its applicability despite small sample sizes and inconclusive data distribution. If consistently applied, the method presented can be used to optimize future sampling and thus reduce sampling costs and efforts while increasing data quality.

scholarly journals Silicon Photomultipliers as a Low-Cost Fluorescence Detector for Capillary Electrophoresis

2020 ◽  
Author(s):  
Brae Petersen ◽  
Luke Gallion ◽  
Nancy Allbritton
Keyword(s):  
Capillary Electrophoresis ◽  
Open Source ◽  
Dynamic Range ◽  
Low Cost ◽  
Single Cells ◽  
Detection Limits ◽  
High Sensitivity ◽  
Small Sample ◽  
Fluorescence Detector ◽  
Silicon Photomultipliers

Capillary electrophoresis (CE) is a highly efficient separation method capable of handling small sample volumes (~pL) and low (~yoctomole) detection limits, and as such is ideal for applications that require high sensitivity such as single-cell analysis. Low-cost CE instrumentation is quickly expanding but low-cost, open-source fluorescence detectors with ultra-sensitive detection limits are lacking. Silicon photomultipliers (SiPM) are inexpensive, low-footprint detectors with the potential to fill the role as a detector when cost, size, and customization are important. In this work we demonstrate the use of a SiPM in CE with zeptomolar detection limits and a dynamic range spanning five orders of magnitude, comparable to photomultiplier detectors. We characterize the performance of the SiPM as a highly sensitive detector by measuring enzyme activity in single cells. This simple, small footprint, and low-cost (<$130) light detection circuit will be beneficial for open-source, portable, and budget friendly instrumentation requiring high sensitivity.<br>

scholarly journals Evaluation of TagSeq, a reliable low-cost alternative for RNAseq

2016 ◽  
Author(s):  
Brian Keith Lohman ◽  
Jesse N Weber ◽  
Daniel I Bolnick
Keyword(s):  
Gene Expression ◽  
Statistical Power ◽  
Low Cost ◽  
Ecological Genetics ◽  
Small Sample ◽  
Sample Sizes ◽  
Experimental Conditions ◽  
Efficient Alternative ◽  
Highly Correlated ◽  
Small Sample Sizes

RNAseq is a relatively new tool for ecological genetics that offers researchers insight into changes in gene expression in response to a myriad of natural or experimental conditions. However, standard RNAseq methods (e.g., Illumina TruSeq® or NEBNext®) can be cost prohibitive, especially when study designs require large sample sizes. Consequently, RNAseq is often underused as a method, or is applied to small sample sizes that confer poor statistical power. Low cost RNAseq methods could therefore enable far greater and more powerful applications of transcriptomics in ecological genetics and beyond. Standard mRNAseq is costly partly because one sequences portions of the full length of all transcripts. Such whole-mRNA data is redundant for estimates of relative gene expression. TagSeq is an alternative method that focuses sequencing effort on mRNAs 3-prime end, thereby reducing the necessary sequencing depth per sample, and thus cost. Here we present a revised TagSeq protocol, and compare its performance against NEBNext®, the gold-standard whole mRNAseq method. We built both TagSeq and NEBNext® libraries from the same biological samples, each spiked with control RNAs. We found that TagSeq measured the control RNA distribution more accurately than NEBNext®, for a fraction of the cost per sample (~10%). The higher accuracy of TagSeq was particularly apparent for transcripts of moderate to low abundance. Technical replicates of TagSeq libraries are highly correlated, and were correlated with NEBNext® results. Overall, we show that our modified TagSeq protocol is an efficient alternative to traditional whole mRNAseq, offering researchers comparable data at greatly reduced cost.

Silicon Photomultipliers as a Low-Cost Fluorescence Detector for Capillary Electrophoresis

2020 ◽  
Author(s):  
Brae Petersen ◽  
Luke Gallion ◽  
Nancy Allbritton
Keyword(s):  
Capillary Electrophoresis ◽  
Open Source ◽  
Dynamic Range ◽  
Low Cost ◽  
Single Cells ◽  
Detection Limits ◽  
High Sensitivity ◽  
Small Sample ◽  
Fluorescence Detector ◽  
Silicon Photomultipliers

Capillary electrophoresis (CE) is a highly efficient separation method capable of handling small sample volumes (~pL) and low (~yoctomole) detection limits, and as such is ideal for applications that require high sensitivity such as single-cell analysis. Low-cost CE instrumentation is quickly expanding but low-cost, open-source fluorescence detectors with ultra-sensitive detection limits are lacking. Silicon photomultipliers (SiPM) are inexpensive, low-footprint detectors with the potential to fill the role as a detector when cost, size, and customization are important. In this work we demonstrate the use of a SiPM in CE with zeptomolar detection limits and a dynamic range spanning five orders of magnitude, comparable to photomultiplier detectors. We characterize the performance of the SiPM as a highly sensitive detector by measuring enzyme activity in single cells. This simple, small footprint, and low-cost (<$130) light detection circuit will be beneficial for open-source, portable, and budget friendly instrumentation requiring high sensitivity.<br>

scholarly journals The comparison of two independent proportions via Design Analysis: Theoretical background and an R implementation

2021 ◽  
Author(s):  
Riccardo Bettin
Keyword(s):  
Statistical Power ◽  
Theoretical Background ◽  
Design Analysis ◽  
Small Sample ◽  
Questionable Research Practices ◽  
Replication Crisis ◽  
Long Time ◽  
Actual Publication ◽  
Small Sample Sizes ◽  
Post Hoc

In the last decade science has fallen into a replication crisis, this means that researches, when replicated, do not give the same results as the original ones. The difficulty in replicating studies can be due to several reasons, some of which regard the scientific world in general, such as the actual publication system that encourages incorrect behaviours and questionable research practices by scientists, and some that change between scientific fields. In fact, some scientific field feel this crisis more than others, and psychology is one of them. Low statistical power and misuse of statistics in psychology is reported from a long time. The first to criticize psychologist in regards of the use of power has been Cohen in 1962. This crisis can lead to the loss of trust in psychology and in science in general, for this reason it is important to find some solutions to the crisis.Several possible solutions have been proposed. In this work we will focus on Design analysis, that is quite a new notion that can help in the process of getting out of the replication crisis. This analysis consists in calculating (power, and) new type of inferential errors to help researchers to better understand the consequences of low power, small sample sizes and studies started without appropriate planning. Design analysis can be done prospectively and retrospectively, that is different from post-hoc power calculations. The aims of this work are mainly to extend the design analysis to the case of differences between independent proportions and to provide an R implementation that can be used by researchers.

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