Amazon Mechanical Turk (AMT) is an online crowdsourcing service where anonymous online workers complete web-based tasks for small sums of money. The service has attracted attention from experimental ...psychologists interested in gathering human subject data more efficiently. However, relative to traditional laboratory studies, many aspects of the testing environment are not under the experimenter's control. In this paper, we attempt to empirically evaluate the fidelity of the AMT system for use in cognitive behavioral experiments. These types of experiment differ from simple surveys in that they require multiple trials, sustained attention from participants, comprehension of complex instructions, and millisecond accuracy for response recording and stimulus presentation. We replicate a diverse body of tasks from experimental psychology including the Stroop, Switching, Flanker, Simon, Posner Cuing, attentional blink, subliminal priming, and category learning tasks using participants recruited using AMT. While most of replications were qualitatively successful and validated the approach of collecting data anonymously online using a web-browser, others revealed disparity between laboratory results and online results. A number of important lessons were encountered in the process of conducting these replications that should be of value to other researchers.
Hopping Hotspots: Global Shifts in Marine Biodiversity Renema, W.; Bellwood, D. R.; Braga, J. C. ...
Science (American Association for the Advancement of Science),
08/2008, Letnik:
321, Številka:
5889
Journal Article
Recenzirano
Hotspots of high species diversity are a prominent feature of modern global biodiversity patterns. Fossil and molecular evidence is starting to reveal the history of these hotspots. There have been ...at least three marine biodiversity hotspots during the past 50 million years. They have moved across almost half the globe, with their timing and locations coinciding with major tectonic events. The birth and death of successive hotspots highlights the link between environmental change and biodiversity patterns. The antiquity of the taxa in the modern Indo-Australian Archipelago hotspot emphasizes the role of pre-Pleistocene events in shaping modern diversity patterns.
The incidence of type 1 diabetes (T1D) is increasing globally. One hypothesis is that increasing childhood obesity rates may explain part of this increase, but, as T1D is rare, intervention studies ...are challenging to perform. The aim of this study was to assess this hypothesis with a Mendelian randomization approach that uses genetic variants as instrumental variables to test for causal associations.
We created a genetic instrument of 23 single nucleotide polymorphisms (SNPs) associated with childhood adiposity in children aged 2-10 years. Summary-level association results for these 23 SNPs with childhood-onset (<17 years) T1D were extracted from a meta-analysis of genome-wide association study with 5,913 T1D cases and 8,828 reference samples. Using inverse-variance weighted Mendelian randomization analysis, we found support for an effect of childhood adiposity on T1D risk (odds ratio 1.32, 95% CI 1.06-1.64 per standard deviation score in body mass index SDS-BMI). A sensitivity analysis provided evidence of horizontal pleiotropy bias (p = 0.04) diluting the estimates towards the null. We therefore applied Egger regression and multivariable Mendelian randomization methods to control for this type of bias and found evidence in support of a role of childhood adiposity in T1D (odds ratio in Egger regression, 2.76, 95% CI 1.40-5.44). Limitations of our study include that underlying genes and their mechanisms for most of the genetic variants included in the score are not known. Mendelian randomization requires large sample sizes, and power was limited to provide precise estimates. This research has been conducted using data from the Early Growth Genetics (EGG) Consortium, the Genetic Investigation of Anthropometric Traits (GIANT) Consortium, the Tobacco and Genetics (TAG) Consortium, and the Social Science Genetic Association Consortium (SSGAC), as well as meta-analysis results from a T1D genome-wide association study.
This study provides genetic support for a link between childhood adiposity and T1D risk. Together with evidence from observational studies, our findings further emphasize the importance of measures to reduce the global epidemic of childhood obesity and encourage mechanistic studies.
This study presents the application of a cost-effective, unmanned aerial vehicle (UAV) to investigate calving dynamics at a major marine-terminating outlet glacier draining the western sector of the ...Greenland ice sheet. The UAV was flown over Store Glacier on three sorties during summer 2013 and acquired over 2000 overlapping, geotagged images of the calving front at an similar to 40 cm ground sampling distance. Stereo-photogrammetry applied to these images enabled the extraction of high-resolution digital elevation models (DEMs) with vertical accuracies of plus or minus 1.9 m which were used to quantify glaciological processes from early July to late August 2013. The central zone of the calving front advanced by similar to 500 m, whilst the lateral margins remained stable. The orientation of crevasses and the surface velocity field derived from feature tracking indicates that lateral drag is the primary resistive force and that ice flow varies across the calving front from 2.5 m d super(-1) at the margins to in excess of 16 m d super(-1) at the centreline. Ice flux through the calving front is 3.8 107 m3 d super(-1), equivalent to 13.9 Gt a super(-1) and comparable to flux-gate estimates of Store Glacier's annual discharge. Water-filled crevasses were present throughout the observation period but covered a limited area of between 0.025 and 0.24% of the terminus and did not appear to exert any significant control over fracture or calving. We conclude that the use of repeat UAV surveys coupled with the processing techniques outlined in this paper have great potential for elucidating the complex frontal dynamics that characterise large calving outlet glaciers.
Deep Learning (DL) has recently enabled unprecedented advances in one of the grand challenges in computational biology: the half-century-old problem of protein structure prediction. In this paper we ...discuss recent advances, limitations, and future perspectives of DL on five broad areas: protein structure prediction, protein function prediction, genome engineering, systems biology and data integration, and phylogenetic inference. We discuss each application area and cover the main bottlenecks of DL approaches, such as training data, problem scope, and the ability to leverage existing DL architectures in new contexts. To conclude, we provide a summary of the subject-specific and general challenges for DL across the biosciences.
Extremely dry conditions were experienced across most of southern Africa during the austral summer (October–March) of 2015/2016, associated with one of the strongest observed El Niño events in the ...Pacific. Dry conditions peaked in the early austral summer months (October–December) producing the most intense drought in the 116‐year historical record, as measured by the intensity of the standardized precipitation index across all spatial scales up to the sub‐continental. We estimate the return period of this extreme early summer drought to be greater than 200 years. The interior and eastern parts of South Africa were particularly hard‐hit with station data showing rainfall totals being at their lowest since at least 1950. The early summer dry conditions make the 2015/2016 event atypical compared to past El Niño events of similar magnitude. We find that key regional circulation patterns, influenced by planetary‐scale processes, play an important role in modulating the spatial and temporal evolution of the summer rainfall during these El Niño events. Specifically, (a) the Angola Low and the South Indian Ocean High, two dominant low‐level circulation features that drive moisture convergence to support convective precipitation in the region, were anomalously weakened in early austral summer of 2015/2016 resulting in less moisture being transported over the continent, and (b) the mid‐level Botswana High was stronger than in previous El Niño years further producing unfavourable conditions for rainfall through stronger subsidence in the mid‐ to upper levels over southern Africa.
Extremely dry conditions (standardized precipitation index shown above) were experienced across most of southern Africa during the austral summer (October–March) of 2015/2016, associated with one of the strongest observed El Niño events in the Pacific. When comparing to past strong El Niño events, it is evident that key regional‐scale circulation patterns, influenced by planetary‐scale processes, play an important role in modulating the spatial and temporal evolution of the summer rainfall during these events.
Family caregivers are crucial for supporting home death. We reviewed published qualitative research on home-based family caregiving at end of life (1998—2008), synthesizing key findings and ...identifying gaps where additional research is needed. Multiple databases were searched and abstracts reviewed for a focus on family caregiving and palliative care; full articles were reviewed to extract data for this review. In total, 105 articles were included. Findings are presented in the following areas: the caregiving experience and contextual features; supporting family caregivers at end of life; caregiving roles and decision-making; and rewards, meaning and coping. We noted a lack of definitional clarity; a reliance on interview methods and descriptive, thematic analyses, and a relative lack of diversity of patient conditions. Research needs are identified in several areas, including the bereavement experience, caregiver ambivalence, access to services, caregiver meaning-making, and relational and contextual influences on family caregiving at end of life.
CYP2D6
and
CYP2C19
polymorphisms affect the exposure, efficacy and safety of tricyclic antidepressants (TCAs), with some drugs being affected by CYP2D6 only (e.g., nortriptyline and desipramine) and ...others by both polymorphic enzymes (e.g., amitriptyline, clomipramine, doxepin, imipramine, and trimipramine). Evidence is presented for
CYP2D6
and
CYP2C19
genotype-directed dosing of TCAs. This document is an update to the 2012 Clinical Pharmacogenetics Implementation Consortium (CPIC) guideline for
CYP2D6
and
CYP2C19
Genotypes and Dosing of Tricyclic Antidepressants.
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