Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
2,863
datasets available to search
ShareScore release 0.9.0
Dataset results
2,863 results for “Challenge”
Data from: Tackling extremes: challenges for ecological and evolutionary research on extreme climatic events
1. Extreme climatic events (ECEs) are predicted to become more frequent as the climate changes. A rapidly increasing number of studies - though few on animals - suggest that the biological consequences of ECEs can be severe. 2. However, ecological research on the impacts of extreme climatic events (ECEs) has been limited by a lack of cohesiveness and structure. ECEs are often poorly defined and have often been confusingly equated with climatic variability, making comparison between studies difficult. Additionally, a focus on short-term studies has provided us with little information on the long-term implications of ECEs, and the descriptive and anecdotal nature of many studies has meant it is still unclear what the key research questions are. 3. Synthesizing the current state of work is essential to identify ways to make progress. We conduct a synthesis of the literature and discuss conceptual and practical challenges faced by research on ECEs. 4. We consider three steps to advance research. First, we discuss the importance of choosing an ECE definition and identify the pros and cons of 'climatological' and 'biological' definitions of ECEs. Second, we advocate research beyond short-term descriptive studies to address questions concerning the long-term implications of ECEs, focussing on selective pressures and phenotypically plastic responses and how they might differ from responses to a changing climatic mean. Finally, we encourage a greater focus on multi-event studies that help us understand the implications of changing patterns of ECEs, through the combined use of modelling, experimental and observational field studies. 5. This paper aims to open a discussion on the definitions, questions and methods currently used to study ECEs, which will lead to a more cohesive approach to future ECE research.
Data from: Vomiting as a symptom and transmission risk in norovirus illness: evidence from human challenge studies
Background: In the US, noroviruses are estimated to cause 21 million cases annually with economic losses reaching $2 billion. Outbreak investigations frequently implicate vomiting as a major transmission risk. However, little is known about the characteristics of vomiting as a symptom or the amount of virus present in emesis. Methodology and Principal Findings: Emesis samples and symptomology data were obtained from previous norovirus human challenge studies with GI.1 Norwalk virus, GII.2 Snow Mountain virus, and a pilot study with GII.1 Hawaii virus. Viral titers in emesis were determined using strain-specific quantitative RT-PCR. In all four studies, vomiting was common with 40–100% of infected subjects vomiting at least once. However, only 45% of subjects with vomiting also had diarrhea. Most of the emesis samples had detectable virus and the mean viral titers were 8.0 x 105 and 3.9 x 104 genomic equivalent copies (GEC)/ml for GI and GII viruses, respectively (p = 0.02). Sample pH was correlated with GII.2 Snow Mountain virus detection. Conclusions and Significance: Half of all subjects with symptomatic infection experienced vomiting and the average subject shed 1.7 x 108 GEC in emesis. Unlike shedding through stool, vomiting is more likely to result in significant environmental contamination, leading to transmission through fomites and airborne droplets. This quantitative data will be critical for risk assessment studies to further understand norovirus transmission and develop effective control measures. The correlation between sample pH and virus detection is consistent with a single site of virus replication in the small intestine and stomach contents becoming contaminated by intestinal reflux. Additionally, the frequency of vomiting without concurrent diarrhea suggests that epidemiology studies that enroll subjects based on the presence of diarrhea may be significantly underestimating the true burden of norovirus disease.
Data from: Mating system affects population performance and extinction risk under environmental challenge
Failure of organisms to adapt to sudden environmental changes may lead to extinction. Mating system, by affecting fertility and the strength of sexual selection, may have a major impact on a population's chances to adapt and survive. Here, we use experimental evolution in bulb mites (Rhizoglyphus robini) to examine the effects of mating system on population performance under environmental change. We demonstrate that populations in which monogamy was enforced suffered a dramatic fitness decline when evolving at an increased temperature, whereas the negative effects of change in thermal environment were alleviated in polygamous populations. Strikingly, within 17 generations, all monogamous populations experiencing higher temperature went extinct, whereas all polygamous populations survived. Our results show that mating systems may have dramatic effects on the risk of extinction under environmental change.
Data from: Large-scale genotyping of highly polymorphic loci by next generation sequencing: how to overcome the challenges to reliably genotype individuals?
Studying the different roles of adaptive genes is still a challenge in evolutionary ecology and requires reliable genotyping of large numbers of individuals. Next-generation sequencing (NGS) techniques enable such large-scale sequencing, but stringent data processing is required. Here, we develop an easy to use methodology to process amplicon-based NGS data and we apply this methodology to reliably genotype four major histocompatibility complex (MHC) loci belonging to MHC class I and II of Alpine marmots (Marmota marmota). Our post-processing methodology allowed us to increase the number of retained reads. The quality of genotype assignment was further assessed using three independent validation procedures. A total of 3069 high-quality MHC genotypes were obtained at four MHC loci for 863 Alpine marmots with a genotype assignment error rate estimated as 0.21%. The proposed methodology could be applied to any genetic system and any organism, except when extensive copy-number variation occurs (that is, genes with a variable number of copies in the genotype of an individual). Our results highlight the potential of amplicon-based NGS techniques combined with adequate post-processing to obtain the large-scale highly reliable genotypes needed to understand the evolution of highly polymorphic functional genes.
Data from: Immune-challenged fish up-regulate their metabolic scope to support locomotion
Energy-based trade-offs occur when investment in one fitness-related trait diverts energy away from other traits. The extent to which such trade-offs are shaped by limits on the rate of conversion of energy ingested in food (e.g. carbohydrates) into chemical energy (ATP) by oxidative metabolism rather than by the amount of food ingested in the first place is, however, unclear. Here we tested whether the ATP required for mounting an immune response will lead to a trade-off with ATP available for physical activity in mosquitofish (Gambusia holbrooki). To this end, we challenged fish either with lipopolysaccharide (LPS) from E. coli or with Sheep Red Blood Cells (SRBC), and measured oxygen consumption at rest and during swimming at maximum speed 24h, 48h and 7 days post-challenge in order to estimate metabolic rates. Relative to saline-injected controls, only LPS-injected fish showed a significantly greater resting metabolic rate two days post-challenge and significantly higher maximal metabolic rates two and seven days post-challenge. This resulted in a significantly greater metabolic scope two days post-challenge, with LPS-fish transiently overcompensating by increasing maximal ATP production more than would be required for swimming in the absence of an immune challenge. LPS-challenged fish therefore increased their production of ATP to compensate physiologically for the energetic requirements of immune functioning. This response would avoid ATP shortages and allow fish to engage in an aerobically-challenging activity (swimming) even when simultaneously mounting an immune response. Nevertheless, relative to controls, both LPS- and SRBC-fish displayed reduced body mass gain one week post-injection, and LPS-fish actually lost mass. The concomitant increase in metabolic scope and reduced body mass gain of LPS-challenged fish indicates that immune-associated trade-offs are not likely to be shaped by limited oxidative metabolic capacities, but may instead result from limitations in the acquisition, assimilation or efficient use of resources.
Data from: Personality and gonadal development as sources of individual variation in response to GnRH challenge in female great tits
Seasonal timing of reproduction is a key life-history trait, but we know little about the mechanisms underlying individual variation in female endocrine profiles associated with reproduction. In birds, 17β-estradiol is a key reproductive hormone that links brain neuroendocrine mechanisms, involved in information processing and decision making, to downstream mechanisms in the liver, where egg-yolk is produced. Here we test, using a simulated induction of the reproductive system through a GnRH-challenge, whether the ovary of pre-breeding female great tits responds to a brain stimulation by increasing estradiol. We also assess how this response is modified by individual-specific traits like age, ovarian follicle size and personality, using females from lines artificially selected for divergent levels of exploratory behaviour. We show that a GnRH injection leads to a rapid increase in circulating concentrations of estradiol but responses varied among individuals. Females with more developed ovarian follicles showed stronger responses and females from lines selected for fast exploratory behaviour showed stronger increases compared to females from the slow line, indicating a heritable component. This study shows that the response of the ovary to a reproductive stimulation from the brain greatly varies among individuals and that this variation can be attributed to several commonly measured individual traits, which sheds light on the mechanisms shaping heritable endocrine phenotypes.
Data from: Ocean warming and acidification may challenge the riverward migration of glass eels
The dramatic decline of European eel (Anguilla anguilla) populations over recent decades has attracted considerable attention and concern. Furthermore, little is known concerning the sensitivity of eel's early stages to projected future environmental change. Here we investigated, for the first time, the potential combined effects of ocean warming (OW; ∆ + 4oC; 18oC) and acidification (OA; ∆ - 0.4 pH units) on the survival and migratory behaviour of A. anguilla glass eels, namely their preference towards riverine cues (freshwater and geosmin). Recently arrived individuals were exposed to isolated and combined OW- and OA–conditions for 100 days, adjusting for the salinity gradients associated with upstream migration. A two-choice test was used to investigate migratory activity and shifts in preference towards freshwater environments. While OW decreased survival and increased migratory activity, OA appears to hinder migratory response, reducing the preference for riverine cues. Our results suggest that future conditions could potentially favor an early settlement of glass eels, reducing the proportion of fully-migratory individuals. Further research into the effects of climate change on eel migration and habitat selection is needed to implement efficient conservation plans for this critically endangered species.
Data from: Challenges in analysis and interpretation of microsatellite data for population genetic studies
Advancing technologies have facilitated the ever-widening application of genetic markers such as microsatellites into new systems and research questions in biology. In light of the data and experience accumulated from several years of using microsatellites, we present here a literature review that synthesizes the limitations of microsatellites in population genetic studies. With a focus on population structure, we review the widely used fixation (FST) statistics and Bayesian clustering algorithms and find that the former can be confusing and problematic for microsatellites and that the latter may be confounded by complex population models and lack power in certain cases. Clustering, multivariate analyses, and diversity-based statistics are increasingly being applied to infer population structure, but in some instances these methods lack formalization with microsatellites. Migration-specific methods perform well only under narrow constraints. We also examine the use of microsatellites for inferring effective population size, changes in population size, and deeper demographic history, and find that these methods are untested and/or highly context-dependent. Overall, each method possesses important weaknesses for use with microsatellites, and there are significant constraints on inferences commonly made using microsatellite markers in the areas of population structure, admixture, and effective population size. To ameliorate and better understand these constraints, researchers are encouraged to analyze simulated datasets both prior to and following data collection and analysis, the latter of which is formalized within the approximate Bayesian computation framework. We also examine trends in the literature and show that microsatellites continue to be widely used, especially in non-human subject areas. This review assists with study design and molecular marker selection, facilitates sound interpretation of microsatellite data while fostering respect for their practical limitations, and identifies lessons that could be applied toward emerging markers and high-throughput technologies in population genetics.
Data from: Fitness consequences of altered feeding behavior in immune-challenged mosquitoes
Background: Malaria-infected mosquitoes have been reported to be more likely to take a blood meal when parasites are infectious than when non-infectious. This change in feeding behavior increases the likelihood of malaria transmission, and has been considered an example of parasite manipulation of host behavior. However, immune challenge with heat-killed Escherichia coli induces the same behavior, suggesting that altered feeding behavior may be driven by adaptive responses of hosts to cope with an immune response, rather than by parasite-specific factors. Here we tested the alternative hypothesis that down-regulated feeding behavior prior to infectiousness is a mosquito adaptation that increases fitness during infection. Methods: We measured the impact of immune challenge and blood feeding on the fitness of individual mosquitoes. After an initial blood meal, Anopheles stephensi Liston mosquitoes were experimentally challenged with heat-killed E. coli at a dose known to mimic the same temporal changes in mosquito feeding behavior as active malaria infection. We then tracked daily egg production and survivorship of females maintained on blood-feeding regimes that either mimicked down-regulated feeding behaviors observed during early malaria infection, or were fed on a four-day feeding cycle typically associated with uninfected mosquitoes. Results: Restricting access to blood meals enhanced mosquito survival but lowered lifetime reproduction. Immune- challenge did not impact either fitness component. Combining fecundity and survival to estimate the population- scale intrinsic rate of increase (r), we found that, contrary to the mosquito adaptation hypothesis, mosquito fitness decreased if blood feeding was delayed following an immune challenge. Conclusions: Our data provide no support for the idea that malaria-induced suppression of blood feeding is an adaptation by mosquitoes to reduce the impact of immune challenge. Alternatively, the behavioral alterations may be neither host nor parasite adaptations, but rather a consequence of constraints imposed on feeding by activation of the mosquito immune response, i.e. non-adaptive illness-induced anorexia. Future work incorporating field conditions and different immune challenges could further clarify the effect of altered feeding on mosquito and parasite fitness.
FIGURE 3 in A new species of Indian caecilian highlights challenges for species delimitation within Gegeneophis Peters, 1879 (Amphibia: Gymnophiona: Indotyphlidae)
FIGURE 3. Habitat at Bedoor, type locality of Gegeneophis tejaswini sp. nov.
Relocating the Full-Ocean-Depth Multifunctional Landers Seafloor Landing Point in the Challenger Deep Based On A Seismological Approach: A Precise Noninversive US-DTM Method Challenges the Traditional Inversive MC Method
<p>The SEGY format raw OBS-Lander data</p>
AeroPath: An airway segmentation benchmark dataset with challenging pathology
Open the record for dataset details and reuse information.
CHALLENGES AND OPPORTUNITIES FOR IMPROVING THE INVESTMENT CLIMATE IN UZBEKISTAN
<p>The research work aims to develop scientific and practical recommendations for improving the investment climate in Uzbekistan.<strong> </strong>In recent years,<strong> </strong>owing to the immensity of the challenges and a lack of institutional and human capacity, the government will have to focus on tackling the impact of the COVID-19 pandemic and the related economic fallout (including the collapse of global energy prices, reduced Chinese demand and the return of labor migrants from abroad.)This presentation aims to give some insights into the investment environment and the analyses of factors influencing it. The findings of the study will benefit both local investors and foreign investors who are interested in assessing investment opportunities in Uzbekistan.</p>
German-French Hackathon / Data challenge in Passau
Open the record for dataset details and reuse information.
NAVIGATING TECHNOLOGICAL CHALLENGES: FOSTERING YOUNG LEARNERS' READING SKILLS
Open the record for dataset details and reuse information.
Unveiling Challenges in Python Library: Insights from Stack Overflow
<p>A dataset of the SANER 2024 ERA track submission "Unveiling Challenges in Python Library: Insights from Stack Overflow" containing all the comments in Stack Overflow that were classified.</p>
TEACHING WRITING TO STUDENTS OF EFL AND THE CHALLENGES FACED BY TEACHERS OF IPER
Open the record for dataset details and reuse information.
Challenges in the Direct Detection of Chirality-induced Spin Selectivity: Investigation of Foldamer-based Donor-acceptor Dyads
<p>Data supporting the original figures 2, 3, 4. and 5 of the related publication.</p>
Cybercrime and Online Safety: Addressing the Challenges and Solutions Related to Cybercrime, Online Fraud, and Ensuring a Safe Digital Environment for All Users— A Case of African States
<h3><strong>Abstract</strong></h3><p>The internet has made the world more linked than ever before. While taking advantage of this online transition, cybercriminals target flaws in online systems, networks, and infrastructure. Businesses, government organizations, people, and communities all across the world, particularly in African countries, are all severely impacted on an economic and social level. Many African countries focused more on developing secure electricity and internet networks; yet, cybersecurity usually receives less attention than it should. One of Africa's major issues is the lack of adequate digital security infrastructure, which has harmed businesses, governmental institutions, and individual communities more than it has helped. The majority of African countries operate without cybersecurity measures in place to combat cyberattacks. Only a few examples of today's cyber risks include digital extortion, business email intrusion, data breaches, online fraud, ransomware, and phishing, and new types of cybercrime are always developing. Due to the advent of new technology, cybercriminals have become more organized and quicker in their attacks and alliance creation. To maintain a secure digital environment for all internet users, this study focused on the challenges, solutions, and need for African countries to improve their online safety by tackling cybercrime, online fraud, and cybersecurity concerns. The objective of this study is to offer practical and long-term answers to the problems posed by cybercrime, with a continuing emphasis on enhancing online safety. It will assess the effectiveness of cutting-edge cybersecurity measures, legislative frameworks, and cross-border cooperative efforts, as well as potential areas for improvement. Additionally, the study will examine cutting-edge methods like blockchain technology, machine learning, and other cutting-edge methods that could improve our using digital defences to stop cybercrime.</p>
Supplementary figure 1. Histopathological analysis of the pseudobranch tissues in Atlantic salmon following SAV3 challenge (by cohabitation) at 16 dpc showing no histological difference between (A) Control fish (non infected) and (B) SAV3-infected fish from HD group at 16 dpc.
Open the record for dataset details and reuse information.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.