USDA-ARS?s Scientific Manuscript database
The potential for gut microbiota to impede or enhance pathogen transmission is well-documented but the factors that shape this microbiota in mosquito vectors are poorly understood. We characterized and compared the gut microbiota of adult females of Culex restuans Theobald from different parents. Cu...
Impacts of Human Activity on the Microbial Communities of Devon Island, Canadian High Arctic
NASA Astrophysics Data System (ADS)
Bywaters, K. B.; Burton, A. S.; Wallace, S. L.; Glass, B. J.
2016-09-01
The impacts of human activities on microbial communities in arctic environments are poorly understood. This project compares the distribution of microbes at the HMP Mars analog site prior to and after human settlement.
Sex Differences in the Reciprocal Behaviour of Children with Autism
ERIC Educational Resources Information Center
Backer van Ommeren, Tineke; Koot, Hans M.; Scheeren, Anke M.; Begeer, Sander
2017-01-01
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in…
REVIEW OF QUANTITATIVE STANDARDS AND GUIDELINES FOR FUNGI IN INDOOR AIR
Exposure to fungal aerosols clearly causes human disease. However, methods for assessing exposure remain poorly understood, and guidelines for interpreting data are often contradictory. The purposes of this paper are to review and compare existing guidelines for indoor airborne...
Relations between Alcohol, Violence and Victimization in Adolescence
ERIC Educational Resources Information Center
Shepherd, J. P.; Sutherland, I.; Newcombe, R. G.
2006-01-01
Background: Compared to links between alcohol and aggression, links between alcohol and vulnerability are poorly understood. Objectives: To determine whether there is a significant relationship between vulnerability to physical violence and alcohol consumption in adolescence independent of a relationship between alcohol consumption and violent…
Mangrove wetland restoration and creation efforts are increasingly proposed as mechanisms to compensate for mangrove wetland loss. However, ecosystem development and functional equivalence in restored and created mangrove wetlands is poorly understood. We compared a 20-yr chrono...
Health-Related Quality of Life in Children with High-Functioning Autism
ERIC Educational Resources Information Center
Potvin, Marie-Christine; Snider, Laurie; Prelock, Patricia A.; Wood-Dauphinee, Sharon; Kehayia, Eva
2015-01-01
The health-related quality of life of school-aged children with high-functioning autism is poorly understood. The objectives of this study were to compare the health-related quality of life of children with high-functioning autism to that of typically developing peers and to compare child-self and parent-proxy reports of health-related quality of…
High School Dropout in Proximal Context: The Triggering Role of Stressful Life Events
ERIC Educational Resources Information Center
Dupéré, Véronique; Dion, Eric; Leventhal, Tama; Archambault, Isabelle; Crosnoe, Robert; Janosz, Michel
2018-01-01
Adolescents who drop out of high school experience enduring negative consequences across many domains. Yet, the circumstances triggering their departure are poorly understood. This study examined the precipitating role of recent psychosocial stressors by comparing three groups of Canadian high school students (52% boys; M[subscript…
USDA-ARS?s Scientific Manuscript database
Genome-wide association studies (GWAS) are a powerful method to dissect the genetic basis of traits, though in practice the effects of complex genetic architecture and population structure remain poorly understood. To compare mapping strategies we dissect the genetic control of flavonoid pigmentatio...
Is body size important? Seasonal changes in morphology in two grass-feeding Abacarus mites
USDA-ARS?s Scientific Manuscript database
Overwintering strategies in herbivorous mites (Acari: Eriophyoidea) are poorly understood. A study of two Abacarus spp., was conducted to compare body size parameters of adult females in different seasons. Mites of Abacarus n. sp. (under description) and A. lolli were sampled from Bromopsis inermis ...
USDA-ARS?s Scientific Manuscript database
Hemicelluloses are major components of plant biomass, but their fermentation in the rumens of cattle and other ruminants is poorly understood. We compared four species of the ruminally dominant genus Prevotella and the well-known hemicellulose utilizer, Butyrivibrio fibrisolvens, with respect to deg...
Amber J. Vanden Wymelenberg; Jill Gaskell; Michael Mozuch; Grzegorz Sabat; John Ralph; Oleksandr Skyba; Shawn D Mansfield; Robert A. Blanchette; Diego Martinez; Igor Grigoriev; Philip J Kersten; Daniel Cullen
2010-01-01
Cellulose degradation by brown rot fungi, such as Postia placenta, is poorly understood relative to the phylogenetically related white rot basidiomycete, Phanerochaete chrysosporium. To elucidate the number, structure, and regulation of genes involved in lignocellulosic cell wall attack, secretome and transcriptome analyses were performed on both wood decay fungi...
USDA-ARS?s Scientific Manuscript database
Soy protein is effective at preventing hepatic steatosis; however, the mechanisms are poorly understood. We tested the hypothesis that soy versus dairy protein-based diet would alter microbiota and attenuate hepatic steatosis in hyperphagic Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Male OLETF ...
Aaron S. Adams; Sandye M. Adams; Cameron R. Currie; Nancy E. Gillette; Kenneth F. Raffa
2010-01-01
Bacterial communities are known to play important roles in insect life histories, yet their consistency or variation across populations is poorly understood. Bacteria associated with the bark beetle Dendroctonus valens LeConte from eight populations, ranging from Wisconsin to Oregon, were evaluated and compared. We used the culture-independent technique of denaturing...
C.R. Breece; T.E. Kolb; B.G. Dickson; J.D. McMillin; K.M. Clancey
2008-01-01
Prescribed fire is an important tool in the management of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forests, yet effects on bark beetle (Coleoptera: Curculionidae, Scolytinae) activity and tree mortality are poorly understood in the southwestern U.S. We compared bark beetle attacks and tree mortality between paired prescribed-burned and...
Effects of fire and browsing on regeneration of blue oak
James W. Bartolome; Mitchel P. McClaran; Barbara H. Allen-Diaz; Jim Dunne; Lawrence D. Ford; Richard B. Standiford; Neil K. McDougald; Larry C. Forero
2002-01-01
Blue oaks (Quercus douglasii) are not regenerating well over much of California. The roles of fire and browsing in regeneration are probably significant, but poorly understood. We burned two foothill blue oak woodland sites which contained significant numbers of small trees between 40 and 70 cm tall, then compared height growth over 14 years among 48...
USDA-ARS?s Scientific Manuscript database
The physiological role and mechanism of nutrient storage within vacuoles of specific cell types is poorly understood. Transcript profiles from "Arabidopsis thaliana" leaf cells differing in calcium concentration ([Ca], epidermis <10 mM versus mesophyll >60 mM) were compared using a microarray screen...
Eric K. Zenner; Michelle A. Martin; Brian J. Palik; Jerilynn E. Peck; Charles R. Blinn
2013-01-01
Partial timber harvest within riparian management zones (RMZs) may permit active management of riparian forests while protecting stream ecosystems, but impacts on herbaceous communities are poorly understood. We compared herbaceous plant community abundance, diversity and composition in RMZs along small streams in northern Minnesota, USA, among four treatments before...
Laboratory tests for mumps vaccines.
Minor, P D
1997-03-01
The action of live attenuated vaccines against mumps is poorly understood although their clinical efficacy is beyond doubt. The attenuated character of the vaccine is assured by consistency of production related to clinical trials, and limited studies of vaccine seeds in primates. Potency is assessed by infectivity in vitro and is subject to poorly understood sources of variation. Molecular biological studies are at an early stage.
Lateral gene transfer in a heavy metal-contaminated-groundwater microbial community
Hemme, Christopher L.; Green, Stefan J.; Rishishwar, Lavanya; ...
2016-04-05
Here, unraveling the drivers controlling the response and adaptation of biological communities to environmental change, especially anthropogenic activities, is a central but poorly understood issue in ecology and evolution. Comparative genomics studies suggest that lateral gene transfer (LGT) is a major force driving microbial genome evolution, but its role in the evolution of microbial communities remains elusive.
ERIC Educational Resources Information Center
Hamlyn-Wright, Sarah; Draghi-Lorenz, Riccardo; Ellis, Jason
2007-01-01
Stress, anxiety and depression are raised amongst parents of children with a developmental disorder. However, the processes by which stress leads to depression and anxiety are poorly understood. In a cross-sectional survey, levels of parental stress, depression and anxiety were compared between parents of children with an autistic disorder,…
ERIC Educational Resources Information Center
Berenguer, Carmen; Miranda, Ana; Colomer, Carla; Baixauli, Inmaculada; Roselló, Belén
2018-01-01
Social difficulties are a key aspect of autism, but the intervening factors are still poorly understood. This study had two objectives: to compare the profile of ToM skills, executive functioning (EF), and pragmatic competence (PC) of children with high-functioning autism (HFA) and children with typical development (TD), and analyze their mediator…
ERIC Educational Resources Information Center
Park, Chun Hui J.; Ganella, Despina E.; Kim, Jee Hyun
2017-01-01
Anxiety disorders emerge early, and girls are significantly more likely to develop anxiety compared to boys. However, sex differences in fear during development are poorly understood. Therefore, we investigated juvenile male and female rats in the relapse behaviors following extinction of conditioned fear. In all experiments, 18-d-old rats first…
Chelcy R. Ford; Robert M. Hubbard; James M. Vose
2010-01-01
Recent studies have shown that planted pine stands exhibit higher evapotranspiration (ET) and are more sensitive to climatic conditions compared with hardwood stands. Whether this is due to management and stand effects, biological effects or their interaction is poorly understood. We estimated growing season canopy- and sap flux-scaled leaf-level transpiration (Ec and...
USDA-ARS?s Scientific Manuscript database
Associations between abnormal body fat distribution and clinical variables are poorly understood in pediatric HIV disease. Our objective was to compare total body fat and its distribution in perinatally HIV-infected and HIV-exposed but uninfected (HEU) children and to evaluate associations with clin...
Yunyun Feng; Dengsheng Lu; Qi Chen; Michael Keller; Emilio Moran; Maiza Nara dos-Santos; Edson Luis Bolfe; Mateus Batistella
2017-01-01
Previous research has explored the potential to integrate lidar and optical data in aboveground biomass (AGB) estimation, but how different data sources, vegetation types, and modeling algorithms influence AGB estimation is poorly understood. This research conducts a comparative analysis of different data sources and modeling approaches in improving AGB estimation....
Telangiectatic osteosarcoma: a review of literature.
Liu, Jun-Jian; Liu, Shen; Wang, Jian-Guang; Zhu, Wei; Hua, Ying-Qi; Sun, Wei; Cai, Zheng-Dong
2013-01-01
Telangiectatic osteosarcoma is a rare variant of osteosarcoma and hence its occurrence, presentation, and prognosis are poorly understood. With advancements in technology and available treatment options, the scenario of its diagnosis, management, and outcome has changed. Chemotherapy with surgery was challenged previously, but has now been proved to be beneficial. We reviewed the available literature and compared results to define the characteristics of the disease, its presentation, radiographic and pathologic features, optimal treatment, and prognosis.
Telangiectatic osteosarcoma: a review of literature
Liu, Jun-jian; Liu, Shen; Wang, Jian-guang; Zhu, Wei; Hua, Ying-qi; Sun, Wei; Cai, Zheng-dong
2013-01-01
Telangiectatic osteosarcoma is a rare variant of osteosarcoma and hence its occurrence, presentation, and prognosis are poorly understood. With advancements in technology and available treatment options, the scenario of its diagnosis, management, and outcome has changed. Chemotherapy with surgery was challenged previously, but has now been proved to be beneficial. We reviewed the available literature and compared results to define the characteristics of the disease, its presentation, radiographic and pathologic features, optimal treatment, and prognosis. PMID:23745051
Comparative Roles of Overexpressed and Mutated H- and K-ras in Mammary Carcinogenesis.
1996-08-01
transgene of these tumors. 14. SUBJECT TERMS 15. NUMBER OF PAGES Breast Cancer , mammary carcinogenesis, oncogenes, ras genes, 44 replication defective...27 Appendix 5 29 Appendix 6 31 Appendix 7 33 Appendix 8 35 Appendix 9 37 Appendix 10 39 Introduction Breast cancer development involves multiple poorly...understood steps (25). Currently, several genes that may participate in breast cancer development are under investigation. The ras family of genes
Artificial Intelligence In Computational Fluid Dynamics
NASA Technical Reports Server (NTRS)
Vogel, Alison Andrews
1991-01-01
Paper compares four first-generation artificial-intelligence (Al) software systems for computational fluid dynamics. Includes: Expert Cooling Fan Design System (EXFAN), PAN AIR Knowledge System (PAKS), grid-adaptation program MITOSIS, and Expert Zonal Grid Generation (EZGrid). Focuses on knowledge-based ("expert") software systems. Analyzes intended tasks, kinds of knowledge possessed, magnitude of effort required to codify knowledge, how quickly constructed, performances, and return on investment. On basis of comparison, concludes Al most successful when applied to well-formulated problems solved by classifying or selecting preenumerated solutions. In contrast, application of Al to poorly understood or poorly formulated problems generally results in long development time and large investment of effort, with no guarantee of success.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peter Daum
2008-10-06
Brookhaven researcher Peter Daum discusses an international field experiment designed to make observations of critical components of the climate system of the southeastern Pacific. Because elements of this system are poorly understood and poorly represent
Peter Daum
2017-12-09
Brookhaven researcher Peter Daum discusses an international field experiment designed to make observations of critical components of the climate system of the southeastern Pacific. Because elements of this system are poorly understood and poorly represent
Middelveen, Marianne J; Stricker, Raphael B
2011-01-01
Bovine digital dermatitis is an emerging infectious disease that causes lameness, decreased milk production, and weight loss in livestock. Proliferative stages of bovine digital dermatitis demonstrate keratin filament formation in skin above the hooves in affected animals. The multifactorial etiology of digital dermatitis is not well understood, but spirochetes and other coinfecting microorganisms have been implicated in the pathogenesis of this veterinary illness. Morgellons disease is an emerging human dermopathy characterized by the presence of filamentous fibers of undetermined composition, both in lesions and subdermally. While the etiology of Morgellons disease is unknown, there is serological and clinical evidence linking this phenomenon to Lyme borreliosis and coinfecting tick-borne agents. Although the microscopy of Morgellons filaments has been described in the medical literature, the structure and pathogenesis of these fibers is poorly understood. In contrast, most microscopy of digital dermatitis has focused on associated pathogens and histology rather than the morphology of late-stage filamentous fibers. Clinical, laboratory, and microscopic characteristics of these two diseases are compared. PMID:22253541
Middelveen, Marianne J; Stricker, Raphael B
2011-01-01
Bovine digital dermatitis is an emerging infectious disease that causes lameness, decreased milk production, and weight loss in livestock. Proliferative stages of bovine digital dermatitis demonstrate keratin filament formation in skin above the hooves in affected animals. The multifactorial etiology of digital dermatitis is not well understood, but spirochetes and other coinfecting microorganisms have been implicated in the pathogenesis of this veterinary illness. Morgellons disease is an emerging human dermopathy characterized by the presence of filamentous fibers of undetermined composition, both in lesions and subdermally. While the etiology of Morgellons disease is unknown, there is serological and clinical evidence linking this phenomenon to Lyme borreliosis and coinfecting tick-borne agents. Although the microscopy of Morgellons filaments has been described in the medical literature, the structure and pathogenesis of these fibers is poorly understood. In contrast, most microscopy of digital dermatitis has focused on associated pathogens and histology rather than the morphology of late-stage filamentous fibers. Clinical, laboratory, and microscopic characteristics of these two diseases are compared.
Doolittle-Hall, Janet M.; Cunningham Glasspoole, Danielle L.; Seaman, William T.; Webster-Cyriaque, Jennifer
2015-01-01
Oncoviruses cause tremendous global cancer burden. For several DNA tumor viruses, human genome integration is consistently associated with cancer development. However, genomic features associated with tumor viral integration are poorly understood. We sought to define genomic determinants for 1897 loci prone to hosting human papillomavirus (HPV), hepatitis B virus (HBV) or Merkel cell polyomavirus (MCPyV). These were compared to HIV, whose enzyme-mediated integration is well understood. A comprehensive catalog of integration sites was constructed from the literature and experimentally-determined HPV integration sites. Features were scored in eight categories (genes, expression, open chromatin, histone modifications, methylation, protein binding, chromatin segmentation and repeats) and compared to random loci. Random forest models determined loci classification and feature selection. HPV and HBV integrants were not fragile site associated. MCPyV preferred integration near sensory perception genes. Unique signatures of integration-associated predictive genomic features were detected. Importantly, repeats, actively-transcribed regions and histone modifications were common tumor viral integration signatures. PMID:26569308
Modeling of the jack rabbit series of experiments with a temperature based reactive burn model
NASA Astrophysics Data System (ADS)
Desbiens, Nicolas
2017-01-01
The Jack Rabbit experiments, performed by Lawrence Livermore National Laboratory, focus on detonation wave corner turning and shock desensitization. Indeed, while important for safety or charge design, the behaviour of explosives in these regimes is poorly understood. In this paper, our temperature based reactive burn model is calibrated for LX-17 and compared to the Jack Rabbit data. It is shown that our model can reproduce the corner turning and shock desensitization behaviour of four out of the five experiments.
van de Pol, Martijn; Vindenes, Yngvild; Sæther, Bernt-Erik; Engen, Steinar; Ens, Bruno J.; Oosterbeek, Kees; Tinbergen, Joost M.
2011-01-01
The relative importance of environmental colour for extinction risk compared with other aspects of environmental noise (mean and interannual variability) is poorly understood. Such knowledge is currently relevant, as climate change can cause the mean, variability and temporal autocorrelation of environmental variables to change. Here, we predict that the extinction risk of a shorebird population increases with the colour of a key environmental variable: winter temperature. However, the effect is weak compared with the impact of changes in the mean and interannual variability of temperature. Extinction risk was largely insensitive to noise colour, because demographic rates are poor in tracking the colour of the environment. We show that three mechanisms—which probably act in many species—can cause poor environmental tracking: (i) demographic rates that depend nonlinearly on environmental variables filter the noise colour, (ii) demographic rates typically depend on several environmental signals that do not change colour synchronously, and (iii) demographic stochasticity whitens the colour of demographic rates at low population size. We argue that the common practice of assuming perfect environmental tracking may result in overemphasizing the importance of noise colour for extinction risk. Consequently, ignoring environmental autocorrelation in population viability analysis could be less problematic than generally thought. PMID:21561978
A Comparative Study of Airflow and Odorant Deposition in the Mammalian Nasal Cavity
NASA Astrophysics Data System (ADS)
Richter, Joseph; Rumple, Christopher; Ranslow, Allison; Quigley, Andrew; Pang, Benison; Neuberger, Thomas; Krane, Michael; van Valkenburgh, Blaire; Craven, Brent
2013-11-01
The complex structure of the mammalian nasal cavity provides a tortuous airflow path and a large surface area for respiratory air conditioning, filtering of inspired contaminants, and olfaction. Due to the small and contorted structure of the nasal turbinals, nasal anatomy and function remains poorly understood in most mammals. Here, we utilize high-resolution MRI scans to reconstruct anatomically-accurate models of the mammalian nasal cavity. These data are used to compare the form and function of the mammalian nose. High-fidelity computational fluid dynamics (CFD) simulations of nasal airflow and odorant deposition are presented and used to compare olfactory function across species (primate, rodent, canine, feline, ungulate).
Research Review: The Neurobiology and Genetics of Maltreatment and Adversity
ERIC Educational Resources Information Center
McCrory, Eamon; De Brito, Stephane A.; Viding, Essi
2010-01-01
The neurobiological mechanisms by which childhood maltreatment heightens vulnerability to psychopathology remain poorly understood. It is likely that a complex interaction between environmental experiences (including poor caregiving) and an individual's genetic make-up influence neurobiological development across infancy and childhood, which in…
Patterns and causes of observed piñon pine mortality in the southwestern United States
Meddens, Arjan J.H.; Hicke, Jeff H.; Macalady, Alison K.; Buotte, P.C.; Cowles, T.R.; Allen, Craig D.
2015-01-01
Recently, widespread piñon pine die-off occurred in the southwestern United States. Here we synthesize observational studies of this event and compare findings to expected relationships with biotic and abiotic factors. Agreement exists on the occurrence of drought, presence of bark beetles and increased mortality of larger trees. However, studies disagree about the influences of stem density, elevation and other factors, perhaps related to study design, location and impact of extreme drought. Detailed information about bark beetles is seldom reported and their role is poorly understood. Our analysis reveals substantial limits to our knowledge regarding the processes that produce mortality patterns across space and time, indicating a poor ability to forecast mortality in response to expected increases in future droughts.
NASA Aims to Create First-Ever Space-Based Sodium Lidar to Study Poorly Understood Mesosphere
2017-12-08
Caption: Mike Krainak (left) and Diego Janches recently won NASA follow-on funding to advance a spaceborne sodium lidar needed to probe Earth’s poorly understood mesosphere. Credits: NASA/W. Hrybyk More: A team of NASA scientists and engineers now believes it can leverage recent advances in a greenhouse-detecting instrument to build the world’s first space-based sodium lidar to study Earth’s poorly understood mesosphere. Scientist Diego Janches and laser experts Mike Krainak and Tony Yu, all of whom work at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, are leading a research-and-development effort to further advance the sodium lidar, which the group plans to deploy on the International Space Station if it succeeds in proving its flightworthiness. Read more: go.nasa.gov/2rcGpSM NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
Auditory Processing Disorders: Acquisition and Treatment
ERIC Educational Resources Information Center
Moore, David R.
2007-01-01
Auditory processing disorder (APD) describes a mixed and poorly understood listening problem characterised by poor speech perception, especially in challenging environments. APD may include an inherited component, and this may be major, but studies reviewed here of children with long-term otitis media with effusion (OME) provide strong evidence…
Olivier Chesneau's Work on Novae
NASA Astrophysics Data System (ADS)
Millour, F.; Lagadec, E.
2015-12-01
Olivier Chesneau founded a brand new field of observational astrophysics with his attempts to resolve the novae expanding fireball from the very first days of the explosion. With the images he could get, he showed that novae do indeed explode in an aspherical way, leading to a change of paradigm for the physics of these yet-poorly understood catastrophic systems. He also set the stage for a new way of estimating novae distances, by directly measuring the sky-size of the fireball and comparing it with spectroscopic scales, taking into account the tremendous effects of the fireball geometry.
Gender Considerations in Violence.
Sorrentino, Renee; Friedman, Susan Hatters; Hall, Ryan
2016-12-01
The role of gender in violence is poorly understood. Research has shown that gender has an important and, at times, distinct role in the prediction of violence. However, this gender disparity diminishes in the setting of mental illness. The risk assessment of violence in women is largely based on research in violent men. There are distinct characteristics in female violence compared with male violence. Attention to these characteristics may lead to the development of gender-dependent tools that can be used to evaluate violence risk. Copyright © 2016 Elsevier Inc. All rights reserved.
Direct Observations of Excess Solar Absorption by Clouds
NASA Technical Reports Server (NTRS)
Pilewskie, Peter; Valero, Francisco P. J.
1995-01-01
Aircraft measurements of solar flux in the cloudy tropical atmosphere reveal that solar absorption by clouds is anomalously large when compared to theoretical estimates. The ratio of cloud forcing at an altitude of 20 kilometers to that at the surface is 1.58 rather than 1.0 as predicted by models. These results were derived from a cloud radiation experiment in which identical instrumentation was deployed on coordinated stacked aircraft. These findings indicate a significant difference between measurements and theory and imply that the interaction between clouds and solar radiation is poorly understood.
Constructing event trees for volcanic crises
Newhall, C.; Hoblitt, R.
2002-01-01
Event trees are useful frameworks for discussing probabilities of possible outcomes of volcanic unrest. Each branch of the tree leads from a necessary prior event to a more specific outcome, e.g., from an eruption to a pyroclastic flow. Where volcanic processes are poorly understood, probability estimates might be purely empirical - utilizing observations of past and current activity and an assumption that the future will mimic the past or follow a present trend. If processes are better understood, probabilities might be estimated from a theoritical model, either subjectively or by numerical simulations. Use of Bayes' theorem aids in the estimation of how fresh unrest raises (or lowers) the probabilities of eruptions. Use of event trees during volcanic crises can help volcanologists to critically review their analysis of hazard, and help officials and individuals to compare volcanic risks with more familiar risks. Trees also emphasize the inherently probabilistic nature of volcano forecasts, with multiple possible outcomes.
Navas de Solis, C
2016-07-01
Arrhythmias are common in equine athletes during and immediately after exercise. Many of these rhythm variations are not clinically relevant. In horses, a link between different exercising arrhythmias and poor performance or between exercising arrhythmias and sudden cardiac death (SCD) is strongly suspected but not fully understood or proven. SCD during races or competitions is rare, but has catastrophic consequences for the safety of the human partner and public perceptions of welfare during equestrian sports. This review summarises current knowledge of equine exercise arrhythmias and their implications in SCD and compares existing principles and recommendations for equine subjects with those for human athletes. © 2016 EVJ Ltd.
Lang, Alexandre; Vernet, Marine; Yang, Qing; Orssaud, Christophe; Londero, Alain; Kapoula, Zoï
2013-01-01
Subjective tinnitus (ST) is a frequent but poorly understood medical condition. Recent studies demonstrated abnormalities in several types of eye movements (smooth pursuit, optokinetic nystagmus, fixation, and vergence) in ST patients. The present study investigates horizontal and vertical saccades in patients with tinnitus lateralized predominantly to the left or to the right side. Compared to left sided ST, tinnitus perceived on the right side impaired almost all the parameters of saccades (latency, amplitude, velocity, etc.) and noticeably the upward saccades. Relative to controls, saccades from both groups were more dysmetric and were characterized by increased saccade disconjugacy (i.e., poor binocular coordination). Although the precise mechanisms linking ST and saccadic control remain unexplained, these data suggest that ST can lead to detrimental auditory, visuomotor, and perhaps vestibular interactions. PMID:23550269
Isotopic signals of summer denitrification in a northern hardwood forested catchment
Sarah K. Wexler; Christine L. Goodale; Kevin J. McGuire; Scott W. Bailey; Peter M. Groffman
2014-01-01
Despite decades of measurements, the nitrogen balance of temperate forest catchments remains poorly understood. Atmospheric nitrogen deposition often greatly exceeds streamwater nitrogen losses; the fate of the remaining nitrogen is highly uncertain. Gaseous losses of nitrogen to denitrification are especially poorly documented and are often ignored. Here, we provide...
Punishment and Welfare: Paternal Incarceration and Families' Receipt of Public Assistance
ERIC Educational Resources Information Center
Sugie, Naomi F.
2012-01-01
The United States criminal justice and welfare systems are two important government institutions in the lives of the poor. Despite many theoretical discussions about their relationship, their operation at the level of offenders and families remains poorly understood. This paper utilizes Fragile Families and Child Wellbeing data to examine how…
Sex differences in the reciprocal behaviour of children with autism.
Backer van Ommeren, Tineke; Koot, Hans M; Scheeren, Anke M; Begeer, Sander
2017-08-01
Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.
Evolution of a sediment wave in an experimental channel
Thomas E. Lisle; James E. Pizzuto; Hiroshi Ikeda; Fujiko Iseya; Yoshinori Kodama
1997-01-01
Abstract - The routing of bed material through channels is poorly understood. We approach the problem by observing and modeling the fate of a low-amplitude sediment wave of poorly sorted sand that we introduced into an experimental channel transporting sediment identical to that of the introduced wave. The wave essentially dispersed upstream and downstream without...
Independent Learning--What We Do When You're Not There
ERIC Educational Resources Information Center
Hockings, Christine; Thomas, Liz; Ottaway, Jim; Jones, Rob
2018-01-01
Independent learning is one of the cornerstones of UK higher education yet it is poorly understood by students and is seen by politicians as a poor substitute for face to face teaching. This paper explores students' understandings, approaches and experiences of independent learning and how they may become more effective independent learners. This…
The role of bedrock groundwater in rainfall-runoff response at hillslope and catchment scales
C. Gabrielli; J.J. McDonnell; W.T. Jarvis
2012-01-01
Bedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Direct hydrometric measurements have been limited due to the logistical challenges associated with drilling through hard rock in steep, remote and often roadless terrain. We used a new portable bedrock drilling system to explore bedrock groundwater dynamics aimed at...
Asian and Pacific Islander American Poverty: The Working Poor and the Jobless Poor.
ERIC Educational Resources Information Center
Toji, Dean S.; Johnson, James H.
1992-01-01
Assesses the incidence of Asian-American and Pacific Islander-American poverty, and offers a theoretical explanation for its existence. It is argued that poverty of Americans of Asian and Pacific Island descent is best understood in the context of the linkage of labor migration and U.S. labor market segmentation. (SLD)
Sources of heavy metals in urban wastewater in Stockholm.
Sörme, L; Lagerkvist, R
2002-10-21
The sources of heavy metals to a wastewater treatment plant was investigated. Sources can be actual goods, e.g. runoff from roofs, wear of tires, food, or activities, e.g. large enterprises, car washes. The sources were identified by knowing the metals content in various goods and the emissions from goods to sewage or stormwater. The sources of sewage water and stormwater were categorized to enable comparison with other research and measurements. The categories were households, drainage water, businesses, pipe sediment (all transported in sewage water), atmospheric deposition, traffic, building materials and pipe sediment (transported in stormwater). Results show that it was possible to track the sources of heavy metals for some metals such as Cu and Zn (110 and 100% found, respectively) as well as Ni and Hg (70% found). Other metals sources are still poorly understood or underestimated (Cd 60%, Pb 50%, Cr 20% known). The largest sources of Cu were tap water and roofs. For Zn the largest sources were galvanized material and car washes. In the case of Ni, the largest sources were chemicals used in the WTP and drinking water itself. And finally, for Hg the most dominant emission source was the amalgam in teeth. For Pb, Cr and Cd, where sources were more poorly understood, the largest contributors for all were car washes. Estimated results of sources from this study were compared with previously done measurements. The comparison shows that measured contribution from households is higher than that estimated (except Hg), leading to the conclusion that the sources of sewage water from households are still poorly understood or that known sources are underestimated. In the case of stormwater, the estimated contributions are rather well in agreement with measured contributions, although uncertainties are large for both estimations and measurements. Existing pipe sediments in the plumbing system, which release Hg and Pb, could be one explanation for the missing amount of these metals. Large enterprises were found to make a very small contribution, 4% or less for all metals studied. Smaller enterprises (with the exception of car washes) have been shown to make a small contribution in another city; the contribution in this case study is still unknown.
Heaton, Paul
2011-01-01
Many jurisdictions have considered relaxing Sunday alcohol sales restrictions, yet such restrictions' effects on public health remain poorly understood. This paper analyzes the effects of legalization of Sunday packaged liquor sales on crime, focusing on the phased introduction of such sales in Virginia beginning in 2004. Differences-in-differences and triple-differences estimates indicate the liberalization increased minor crime by 5% and alcohol-involved serious crime by 10%. The law change did not affect domestic crime or induce significant geographic or inter-temporal crime displacement. The costs of this additional crime are comparable to the state's revenues from increased liquor sales. PMID:22125348
NASA Astrophysics Data System (ADS)
Mukherji, Debashish; Marques, Carlos M.; Kremer, Kurt
2018-01-01
In this work we discuss two mirror but distinct phenomena of polymer paradoxical properties in mixed solvents: co-non-solvency and co-solvency. When a polymer collapses in a mixture of two miscible good solvents the phenomenon is known as co-non-solvency, while co-solvency is a phenomenon that is associated with the swelling of a polymer in poor solvent mixtures. A typical example of co-non-solvency is provided by poly(N-isopropylacrylamide) in aqueous alcohol, while poly(methyl methacrylate) in aqueous alcohol shows co-solvency. We discuss these two phenomena to compare their microscopic origins and show that both can be understood within generic universal concepts. A broad range of polymers is therefore expected to exhibit these phenomena where specific chemical details play a lesser role than the appropriate combination of interactions between the trio of molecular components.
Investigation of Nitride Morphology After Self-Aligned Contact Etch
NASA Technical Reports Server (NTRS)
Hwang, Helen H.; Keil, J.; Helmer, B. A.; Chien, T.; Gopaladasu, P.; Kim, J.; Shon, J.; Biegel, Bryan (Technical Monitor)
2001-01-01
Self-Aligned Contact (SAC) etch has emerged as a key enabling technology for the fabrication of very large-scale memory devices. However, this is also a very challenging technology to implement from an etch viewpoint. The issues that arise range from poor oxide etch selectivity to nitride to problems with post etch nitride surface morphology. Unfortunately, the mechanisms that drive nitride loss and surface behavior remain poorly understood. Using a simple langmuir site balance model, SAC nitride etch simulations have been performed and compared to actual etched results. This approach permits the study of various etch mechanisms that may play a role in determining nitride loss and surface morphology. Particle trajectories and fluxes are computed using Monte-Carlo techniques and initial data obtained from double Langmuir probe measurements. Etched surface advancement is implemented using a shock tracking algorithm. Sticking coefficients and etch yields are adjusted to obtain the best agreement between actual etched results and simulated profiles.
Fijal, Bonnie A; Guo, Yingying; Li, Si G; Ahl, Jonna; Goto, Taro; Tanaka, Yoko; Nisenbaum, Laura K; Upadhyaya, Himanshu P
2015-10-01
Atomoxetine, which is indicated for treatment of attention-deficit hyperactivity disorder (ADHD), is predominantly metabolized by genetically polymorphic cytochrome P450 2D6 (CYP2D6). Based on identified CYP2D6 genotypes, individuals can be categorized into 4 phenotypic metabolizer groups as ultrarapid, extensive, intermediate, and poor. Previous studies have focused on observed differences between poor and extensive metabolizers, but it is not well understood whether the safety profile of intermediate metabolizers differs from that of ultrarapid and extensive metabolizers. This study compared safety and tolerability among the different CYP2D6 metabolizer groups in the 12-week open-label phase of an atomoxetine study in adult patients with ADHD. Genotyping identified 1039 patients as extensive/ultrarapid metabolizers, 780 patients as intermediate metabolizers, and 117 patients as poor metabolizers. Common (≥5% frequency) treatment-emergent adverse events did not significantly differ between extensive/ultrarapid and intermediate metabolizers (odds ratios were <2.0 or >0.5). Poor metabolizers had higher frequencies of dry mouth, erectile dysfunction, hyperhidrosis, insomnia, and urinary retention compared with the other metabolizer groups. There were no significant differences between extensive/ultrarapid and intermediate metabolizers in changes from baseline in vital signs. These results suggest that data from CYP2D6 intermediate and extensive/ultrarapid metabolizers can be combined when considering safety analyses related to atomoxetine. © 2015, The American College of Clinical Pharmacology.
Costa, Pedro A. C.; Leoratti, Fabiana M. S.; Figueiredo, Maria M.; Tada, Mauro S.; Pereira, Dhelio B.; Junqueira, Caroline; Soares, Irene S.; Barber, Daniel L.; Gazzinelli, Ricardo T.; Antonelli, Lis R. V.
2015-01-01
The function and regulation of the immune response triggered during malaria is complex and poorly understood, and there is a particular paucity of studies conducted in humans infected with Plasmodium vivax. While it has been proposed that T-cell-effector responses are crucial for protection against blood-stage malaria in mice, the mechanisms behind this in humans remain poorly understood. Experimental models of malaria have shown that the regulatory molecules, cytotoxic T-lymphocyte attenuator-4 (CTLA-4), lymphocyte activation gene-3 (LAG-3), and programmed death-1 (PD-1) are involved in the functional impairment of T cells during infection. Our goal was to define the role of these molecules during P. vivax malaria. We demonstrate that infection triggers the expression of regulatory molecules on T cells. The pattern of expression differs in CD4+ and CD8+ T cells. Higher frequencies of CD4+ express more than 1 regulatory molecule compared to CD8+ T cells. Moreover, lower proportions of CD4+ T cells coexpress regulatory molecules, but are still able to proliferate. Importantly, simultaneously blockade of the CLTA-4, PD-1, and T-cell immunoglobulin and mucin–3 signaling restores the cytokine production by antigen-specific cells. These data support the hypothesis that upregulation of inhibitory receptors on T cells during P. vivax malaria impairs parasite-specific T-cell effector function. PMID:26019284
Falk Delgado, Alberto; Falk Delgado, Anna
2017-08-23
Inconsistent reporting of clinical trials is well-known in the literature. Despite this, factors associated with poor practice such as outcome switching in clinical trials are poorly understood. We performed a cross-sectional analysis to evaluate the prevalence of, and the factors associated with outcome switching. PubMed and Embase were searched for pharmaceutical randomized controlled trials (RCTs) in oncology reporting on a surrogate primary outcome published in 2015. Outcome switching was present in 18% (39/216). First-author male sex was significantly more likely associated with outcome switching compared to female sex with an OR of 3.05 (95% CI 1.07-8.64, p = 0.04) after multivariable adjustment. For-profit funded RCTs were less likely associated with outcome switching compared to non-profit funded research with an OR of 0.22 (95% CI 0.07-0.74, p = 0.01). First author male sex was more likely associated with outcome switching compared to female sex in drug oncology RCTs reporting on a primary surrogate endpoint. For-profit funded research was less likely associated with outcome switching compared to research funded by non-profit organizations. Furthermore, 18 percent of drug oncology trials reporting on a surrogate endpoint could have a higher risk of false positive results due to primary outcome switching.
Liangjun Hu; Qinfeng Guo
2013-01-01
How species diversity relates to productivity remains a major debate. To date, however, the underlying mechanisms that regulate the ecological processes involved are still poorly understood. Three major issues persist in early efforts at resolution. First, in the context that productivity drives species diversity, how the pathways operate is poorly-explained. Second,...
USDA-ARS?s Scientific Manuscript database
Stunting affects ~25% of children <5 y of age and is associated with impaired cognitive and motor development and increased morbidity and mortality. The pathogenesis of stunting is poorly understood. The purpose of this study was to identify altered metabolic pathways associated with child stunting...
Muscle Functional Morphology in Paleobiology: The Past, Present, and Future of "Paleomyology".
Perry, Jonathan M G; Prufrock, Kristen A
2018-03-01
Our knowledge of muscle anatomy and physiology in vertebrates has increased dramatically over the last two-hundred years. Today, much is understood about how muscles contract and about the functional meaning of muscular variation at multiple scales. Progress in muscle anatomy has profited from the availability of broad comparative samples, advances in microscopy have permitted comparisons at increasingly finer scales, and progress in muscle physiology has profited from many carefully designed and executed experiments. Several avenues of future work are promising. In particular, muscle ontogeny (growth and development) is poorly understood for many vertebrate groups. We consider which types of advances in muscle functional morphology are of use to paleobiologists. These are only a modest subset for muscle anatomy and a very small subset for muscle physiology. The relationship between muscle and bone - spatially and mechanically-is critical to any future advances in "paleomyology". Anat Rec, 301:538-555, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.
Crawford, LaTasha K; Rahman, Shumaia F; Beck, Sheryl G
2013-01-16
Anxiety disorders are among the most prevalent psychiatric disorders, yet much is unknown about the underlying mechanisms. The dorsal raphe (DR) is at the crux of the anxiety-inducing effects of uncontrollable stress, a key component of models of anxiety. Though DR serotonin (5-HT) neurons play a prominent role, anxiety-associated changes in the physiology of 5-HT neurons remain poorly understood. A 5-day social defeat model of anxiety produced a multifaceted, anxious phenotype in intruder mice that included increased avoidance behavior in the open field test, increased stress-evoked grooming, and increased bladder and heart weights when compared to control mice. Intruders were further compared to controls using electrophysiology recordings conducted in midbrain slices wherein recordings targeted 5-HT neurons of the ventromedial (vmDR) and lateral wing (lwDR) subfields of the DR. Though defining membrane characteristics of 5-HT neurons were unchanged, γ-aminobutyric-acid-mediated (GABAergic) synaptic regulation of 5-HT neurons was altered in a topographically specific way. In the vmDR of intruders, there was a decrease in the frequency and amplitude of GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs). However, in the lwDR, there was an increase in the strength of inhibitory signals due to slower sIPSC kinetics. Synaptic changes were selective for GABAergic input, as glutamatergic synaptic input was unchanged in intruders. The distinct inhibitory regulation of DR subfields provides a mechanism for increased 5-HT output in vmDR target regions and decreased 5-HT output in lwDR target regions, divergent responses to uncontrollable stress that have been reported in the literature but were previously poorly understood.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McLachlan, M.S.
The digestive tract absorption of environmental contaminants is an important but poorly understood parameter in contaminant is an important but poorly understood parameter in contaminant risk assessments. The net absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant was measured under natural conditions over 12 days. The levels of the substances in the mother's milk were typical for Germany. It was found that for almost all congeners over 90% of the ingested compound was absorbed. This indicates that the common assumption of 100% absorption in nursing infants is reasonable. No firm conclusions could be drawn regarding the absorptionmore » of Cl7- and Cl8DD/F due to high blank levels in the cotton diapers used.« less
Poorly Understood Aspects of Striated Muscle Contraction
Månsson, Alf
2015-01-01
Muscle contraction results from cyclic interactions between the contractile proteins myosin and actin, driven by the turnover of adenosine triphosphate (ATP). Despite intense studies, several molecular events in the contraction process are poorly understood, including the relationship between force-generation and phosphate-release in the ATP-turnover. Different aspects of the force-generating transition are reflected in the changes in tension development by muscle cells, myofibrils and single molecules upon changes in temperature, altered phosphate concentration, or length perturbations. It has been notoriously difficult to explain all these events within a given theoretical framework and to unequivocally correlate observed events with the atomic structures of the myosin motor. Other incompletely understood issues include the role of the two heads of myosin II and structural changes in the actin filaments as well as the importance of the three-dimensional order. We here review these issues in relation to controversies regarding basic physiological properties of striated muscle. We also briefly consider actomyosin mutation effects in cardiac and skeletal muscle function and the possibility to treat these defects by drugs. PMID:25961006
Poorly understood aspects of striated muscle contraction.
Månsson, Alf; Rassier, Dilson; Tsiavaliaris, Georgios
2015-01-01
Muscle contraction results from cyclic interactions between the contractile proteins myosin and actin, driven by the turnover of adenosine triphosphate (ATP). Despite intense studies, several molecular events in the contraction process are poorly understood, including the relationship between force-generation and phosphate-release in the ATP-turnover. Different aspects of the force-generating transition are reflected in the changes in tension development by muscle cells, myofibrils and single molecules upon changes in temperature, altered phosphate concentration, or length perturbations. It has been notoriously difficult to explain all these events within a given theoretical framework and to unequivocally correlate observed events with the atomic structures of the myosin motor. Other incompletely understood issues include the role of the two heads of myosin II and structural changes in the actin filaments as well as the importance of the three-dimensional order. We here review these issues in relation to controversies regarding basic physiological properties of striated muscle. We also briefly consider actomyosin mutation effects in cardiac and skeletal muscle function and the possibility to treat these defects by drugs.
Linking Early Environmental Exposures to Adult Diseases
... diseases. Given that many disorders arise during fetal development from disruptions in the dynamic but still poorly understood interplay of genes, environment and nutrition, prevention may have to occur decades ...
Bratanova, Boyka; Loughnan, Steve; Klein, Olivier; Wood, Robert
2016-06-01
Economic inequality has a robust negative effect on a range of important societal outcomes, including health, wellbeing, and education. Yet, it remains insufficiently understood why, how, and by whom unequal systems tend to be perpetuated. In two studies we examine whether psychological mindsets adopted by the wealthy and the poor in their micro-social transactions act to perpetuate or challenge inequality. We hypothesized that occupying a wealthier socioeconomic position promotes the pursuit of self-interest and contributes to inequality maintenance; poorer socioeconomic position, on the other hand, should promote the pursuit of fairness and equality restoration. In Study 1, participants completed an ultimatum game as proposers after being primed to believe they are wealthier or poorer, offering money to either poor or wealthy responders. As expected, the wealthy pursued their self-interest and the net effect of this behavior contributes to the maintenance of inequality. Conversely, the poor pursued fairness and the net effect of this behavior challenges inequality. In Study 2, participants were responders deciding whether to accept or reject unfair distributions. Compared to the wealthier, the poorer challenged inequality by rejecting unequal offers. The links between micro-social processes and macro-societal inequality are discussed. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
An inexpensive and portable drill rig for bedrock groundwater studies in headwater catchments
C. Gabrielli; J.J. McDonnell
2011-01-01
Bedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Here, we present an inexpensive and portable bedrock drilling system designed for use in remote locations. Our system is capable of drilling bedrock wells up to 11 m deep and 38 mm in diameter in a wide range of bedrock types. The drill consists of a lawn mower engine...
Researchers Realize Major Breakthrough in Understanding Endometriosis
... a rarely studied and poorly understood disease that affects many, many women.” Health Terms: Women's Health RELATED LINKS RSS LISTSERV YOUTUBE FACEBOOK TWITTER GOOGLE+ NIH...T URNING D ISCOVERY I ...
Modeling Kicks from the Merger of Generic Black-hole Binaries
NASA Technical Reports Server (NTRS)
Baker, John G.; Boggs, William D.; Centrella, Joan; Kelly, Bernard J.; McWilliams, Sean T.; Miller, M. Coleman; vanMeter, James R.
2008-01-01
Recent numerical relativistic results demonstrate that the merger of comparable-mass spinning black holes has a maximum "recoil kick" of up to approx. 4000 km/s. However the scaling of these recoil velocities with mass ratio is poorly understood. We present new runs showing that the maximum possible kick parallel to the orbital axis does not scale as approx. eta(sup 2) (where eta is the symmetric mass ratio), as previously proposed, but is more consistent with approx. eta(sup 3). We discuss the effect of this dependence on galactic ejection scenarios and retention of intermediate-mass black holes in globular clusters. S
Comparative transcriptional profiling of human Merkel cells and Merkel cell carcinoma.
Mouchet, Nicolas; Coquart, Nolwenn; Lebonvallet, Nicolas; Le Gall-Ianotto, Christelle; Mogha, Ariane; Fautrel, Alain; Boulais, Nicholas; Dréno, Brigitte; Martin, Ludovic; Hu, Weiguo; Galibert, Marie-Dominique; Misery, Laurent
2014-12-01
Merkel cell carcinoma is believed to be derived from Merkel cells after infection by Merkel cell polyomavirus (MCPyV) and other poorly understood events. Transcriptional profiling using cDNA microarrays was performed on cells from MCPy-negative and MCPy-positive Merkel cell carcinomas and isolated normal Merkel cells. This microarray revealed numerous significantly upregulated genes and some downregulated genes. The extensive list of genes that were identified in these experiments provides a large body of potentially valuable information of Merkel cell carcinoma carcinogenesis and could represent a source of potential targets for cancer therapy. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
76 FR 61379 - Final Recovery Plan, Bexar County Karst Invertebrates
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-04
... 200, Austin, TX (512-490-0057 ext. 223). FOR FURTHER INFORMATION CONTACT: Adam Zerrenner, at the above... poorly understood, recovery is also dependant on incorporating research findings into adaptive management...
Kierepka, E M; Latch, E K
2016-01-01
Landscape genetics is a powerful tool for conservation because it identifies landscape features that are important for maintaining genetic connectivity between populations within heterogeneous landscapes. However, using landscape genetics in poorly understood species presents a number of challenges, namely, limited life history information for the focal population and spatially biased sampling. Both obstacles can reduce power in statistics, particularly in individual-based studies. In this study, we genotyped 233 American badgers in Wisconsin at 12 microsatellite loci to identify alternative statistical approaches that can be applied to poorly understood species in an individual-based framework. Badgers are protected in Wisconsin owing to an overall lack in life history information, so our study utilized partial redundancy analysis (RDA) and spatially lagged regressions to quantify how three landscape factors (Wisconsin River, Ecoregions and land cover) impacted gene flow. We also performed simulations to quantify errors created by spatially biased sampling. Statistical analyses first found that geographic distance was an important influence on gene flow, mainly driven by fine-scale positive spatial autocorrelations. After controlling for geographic distance, both RDA and regressions found that Wisconsin River and Agriculture were correlated with genetic differentiation. However, only Agriculture had an acceptable type I error rate (3–5%) to be considered biologically relevant. Collectively, this study highlights the benefits of combining robust statistics and error assessment via simulations and provides a method for hypothesis testing in individual-based landscape genetics. PMID:26243136
Jonathan P. Benstead; James G. March; Catherine M. Pringle; Katherine C. Ewel; John W. Short
2009-01-01
Pacific island stream communities are species-poor because of the effects of extreme geographic isolation on colonization rates of taxa common to continental regions. The effects of such low species richness on stream ecosystem function are not well understood. Here, we provide data on community structure and leaf litter breakdown rate in a virtually pristine stream on...
Variation in the Gut Microbiota of Termites (Tsaitermes ampliceps) Against Different Diets.
Su, Lijuan; Yang, Lele; Huang, Shi; Li, Yan; Su, Xiaoquan; Wang, Fengqin; Bo, Cunpei; Wang, En Tao; Song, Andong
2017-01-01
Termites are well recognized for their thriving on recalcitrant lignocellulosic diets through nutritional symbioses with gut-dwelling microbiota; however, the effects of diet changes on termite gut microbiota are poorly understood, especially for the lower termites. In this study, we employed high-throughput 454 pyrosequencing of 16S V1-V3 amplicons to compare gut microbiotas of Tsaitermes ampliceps fed with lignin-rich and lignin-poor cellulose diets after a 2-week-feeding period. As a result, the majority of bacterial taxa were shared across the treatments with different diets, but their relative abundances were modified. In particular, the relative abundance was reduced for Spirochaetes and it was increased for Proteobacteria and Bacteroides by feeding the lignin-poor diet. The evenness of gut microbiota exhibited a significant difference in response to the diet type (filter paper diets < corn stover diets < wood diets), while their richness was constant, which may be related to the lower recalcitrance of this biomass to degradation. These results have important implications for sampling and analysis strategies to probe the lignocellulose degradation features of termite gut microbiota and suggest that the dietary lignocellulose composition could cause shifting rapidly in the termite gut microbiota.
Cario, Gunnar; Fetz, Andrea; Bretscher, Christian; Möricke, Anja; Schrauder, Andre; Stanulla, Martin; Schrappe, Martin
2008-09-01
Response to initial glucocorticoid (GC) treatment is a strong prognostic factor in childhood acute lymphoblastic leukemia (ALL). Patients with a poor prednisone response (PPR) have a poor event-free survival as compared to those with a good prednisone response (PGR). Causes of prednisone resistance are still not well understood. We hypothesized that GC resistance is an intrinsic feature of ALL cells which is reflected in the gene expression pattern and analyzed genome-wide gene expression using microarrays. A case-control study was performed comparing gene expression profiles from initial ALL samples of 20 patients with PPR and those of 20 patients with PGR. Differential gene expression of a subset of genes was confirmed by real-time quantitative polymerase chain reaction analysis and validation was performed in a second independent patient sample (n=20). We identified 121 genes that clearly distinguished prednisone-resistant from sensitive ALL samples (FDR<5%, fold change>or=1.5). Differential gene expression of 21 of these genes could be validated in a second independent set. Of importance, there was a remarkable concordance of genes identified by comparing expression signatures of PPR and PGR cells at diagnosis and those previously described to be up- or downregulated in leukemic cells persisting under GC treatment. Thus, GC resistance seems at least in part to be an intrinsic feature of leukemic cells. Leukemic cells of patients with PPR are characterized by gene expression pattern which are similar to those of resistant cells persisting under glucocorticoid treatment.
The public's belief about biology.
Wolpert, L
2007-02-01
This short review is concerned with a topic that has been neglected and is still very poorly understood: what the general public think and believe about biology (including health and medicine, and bioethics), and, in particular, about biotechnology.
A Production Function Approach to Regional Environmental-Economic Assessments
Numerous difficulties await those creating regional-scale environmental assessments, from data having inconsistent spatial or temporal scales to poorly understood environmental processes and indicators. Including socioeconomic variables further complicates the situation. In place...
Systemic Sclerosis-Associated Pulmonary Arterial Hypertension
Chaisson, Neal F.
2013-01-01
Pulmonary arterial hypertension (PAH) is the leading cause of death in systemic sclerosis (SSc) and affects up to 12% of all patients with SSc, with a 50% mortality rate within 3 years of PAH diagnosis. Compared with the idiopathic form of PAH (IPAH), patients with SSc-associated PAH (SSc-PAH) have a threefold increased risk of death and may receive a diagnosis late in the course of disease because of insidious onset and the high prevalence of cardiac, musculoskeletal, and pulmonary parenchymal comorbidities. Treatment with conventional forms of PAH therapy often yield poor results compared with IPAH cohorts; unfortunately, the exact reasons behind this remain poorly understood but likely include variations in the pathologic mechanisms, differences in cardiovascular response to increasing afterload, and inadequate strategies to detect and treat SSc-PAH early in its course. Current methods for screening and longitudinal evaluation of SSc-PAH, such as the 6-min walk test, transthoracic echocardiography, and MRI, each have notable advantages and disadvantages. We provide an up-to-date, focused review of SSc-PAH and how it differs from IPAH, including pathogenesis, appropriate screening for disease onset, and new approaches to treatment and longitudinal assessment of this disease. PMID:24081346
Understanding sleep disturbance in athletes prior to important competitions.
Juliff, Laura E; Halson, Shona L; Peiffer, Jeremiah J
2015-01-01
Anecdotally many athletes report worse sleep in the nights prior to important competitions. Despite sleep being acknowledged as an important factor for optimal athletic performance and overall health, little is understood about athlete sleep around competition. The aims of this study were to identify sleep complaints of athletes prior to competitions and determine whether complaints were confined to competition periods. Cross-sectional study. A sample of 283 elite Australian athletes (129 male, 157 female, age 24±5 y) completed two questionnaires; Competitive Sport and Sleep questionnaire and the Pittsburgh Sleep Quality Index. 64.0% of athletes indicated worse sleep on at least one occasion in the nights prior to an important competition over the past 12 months. The main sleep problem specified by athletes was problems falling asleep (82.1%) with the main reasons responsible for poor sleep indicated as thoughts about the competition (83.5%) and nervousness (43.8%). Overall 59.1% of team sport athletes reported having no strategy to overcome poor sleep compared with individual athletes (32.7%, p=0.002) who utilised relaxation and reading as strategies. Individual sport athletes had increased likelihood of poor sleep as they aged. The poor sleep reported by athletes prior to competition was situational rather than a global sleep problem. Poor sleep is common prior to major competitions in Australian athletes, yet most athletes are unaware of strategies to overcome the poor sleep experienced. It is essential coaches and scientists monitor and educate both individual and team sport athletes to facilitate sleep prior to important competitions. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.
Blaming the helpers: the marginalization of teachers and parents of the urban poor.
Farber, B A; Azar, S T
1999-10-01
The nature and origins of the current tendency toward disparaging parents and teachers of the urban poor are examined. It is suggested that the influence of parents and teachers must be understood in the context of multiple intervening variables. Several explanations are offered for the phenomenon of blame, including the fact that women constitute the great majority of teachers and are often the primary agents of parenting.
PHYTOASSESSMENT OF ESTUARINE SEDIMENTS
Most sediment quality assessments and quality guidelines are based on the laboratory response of single animal species and benthic animal community composition. The role of plants in this hazard assessment process is poorly understood despite the fact that plant-dominated habitat...
FACTORS INFLUENCING LIGHT-INDUCED MORTALITY OF ENTEROCOCCI IN SEDIMENT SUSPENSIONS
Contamination of recreational waters by pathogenic microorganisms occurs through complex, poorly understood interactions involving variable microbial sources, hydrodynamic transport, arid microbial fate processes. Fecal indicator bacteria such as enterococci have been used to ass...
K. J. McFarlane; S. H. Schoenholtz; R. F. Powers
2009-01-01
Belowground C and N storage is important in maintaining forestproductivity and to CO2 sequestration. How these pools respondto management is poorly understood. We investigated effectsof repeated applications of complete fertilizer and competing...
Predictive Models of Liver Cancer
Predictive models of chemical-induced liver cancer face the challenge of bridging causative molecular mechanisms to adverse clinical outcomes. The latent sequence of intervening events from chemical insult to toxicity are poorly understood because they span multiple levels of bio...
What Can Plasticity Contribute to Insect Responses to Climate Change?
Sgrò, Carla M; Terblanche, John S; Hoffmann, Ary A
2016-01-01
Plastic responses figure prominently in discussions on insect adaptation to climate change. Here we review the different types of plastic responses and whether they contribute much to adaptation. Under climate change, plastic responses involving diapause are often critical for population persistence, but key diapause responses under dry and hot conditions remain poorly understood. Climate variability can impose large fitness costs on insects showing diapause and other life cycle responses, threatening population persistence. In response to stressful climatic conditions, insects also undergo ontogenetic changes including hardening and acclimation. Environmental conditions experienced across developmental stages or by prior generations can influence hardening and acclimation, although evidence for the latter remains weak. Costs and constraints influence patterns of plasticity across insect clades, but they are poorly understood within field contexts. Plastic responses and their evolution should be considered when predicting vulnerability to climate change-but meaningful empirical data lag behind theory.
Activity-Induced Remodeling of Olfactory Bulb Microcircuits Revealed by Monosynaptic Tracing
Arenkiel, Benjamin R.; Hasegawa, Hiroshi; Yi, Jason J.; Larsen, Rylan S.; Wallace, Michael L.; Philpot, Benjamin D.; Wang, Fan; Ehlers, Michael D.
2011-01-01
The continued addition of new neurons to mature olfactory circuits represents a remarkable mode of cellular and structural brain plasticity. However, the anatomical configuration of newly established circuits, the types and numbers of neurons that form new synaptic connections, and the effect of sensory experience on synaptic connectivity in the olfactory bulb remain poorly understood. Using in vivo electroporation and monosynaptic tracing, we show that postnatal-born granule cells form synaptic connections with centrifugal inputs and mitral/tufted cells in the mouse olfactory bulb. In addition, newly born granule cells receive extensive input from local inhibitory short axon cells, a poorly understood cell population. The connectivity of short axon cells shows clustered organization, and their synaptic input onto newborn granule cells dramatically and selectively expands with odor stimulation. Our findings suggest that sensory experience promotes the synaptic integration of new neurons into cell type-specific olfactory circuits. PMID:22216277
The Multifactorial Epidemiology of Blackwater Fever.
Shanks, G Dennis
2017-12-01
Blackwater fever is a massive hemolytic event usually occurring in the context of repeated falciparum malaria infections and intermittent quinine use. Its etiology is poorly understood, and it is rarely seen today. Historical epidemiological observations from the 20th century demonstrated variable patterns in prisoners in Andaman Islands, refugees in Macedonia, canal workers in Panama, expatriates in Rhodesia, and Second World War soldiers. Rates of blackwater fever per 1,000 malaria cases varied over two orders of magnitude. Islands, such as the Andaman Islands and New Guinea, had lower blackwater fever rates than continental areas. During the Second World War, blackwater fever rates in British soldiers in West Africa and Australian soldiers in New Guinea differed by a factor of 40 despite similar treatment regimens and falciparum malaria transmission risks. Blackwater fever is a complex interaction between host erythrocyte, falciparum malaria, and antimalarial drugs which remains poorly understood.
Rosas, Lisa G.; Guendelman, Sylvia; Harley, Kim; Fernald, Lia C. H.; Neufeld, Lynnette; Mejia, Fabiola
2010-01-01
The prevalence of childhood obesity is high among young children of Mexican origin in the United States, however, the determinants are poorly understood. We conducted a binational study with a sample from California (CA) and Mexico (MX), to identify and compare the most important factors associated with overweight and obesity among children of Mexican descent. Significantly more children were classified as overweight or obese in CA compared to MX (53.3 vs. 14.9%, P < 0.01). In CA and MX, having an obese mother was significantly associated with being overweight or obese. In MX, male gender, high socioeconomic status and very low food insecurity were associated with being overweight or obese. These data offer hypotheses for how migration may influence the high prevalence of overweight among the Mexican children in California. PMID:20217234
Rollins, Angela L.; Salyers, Michelle P.; Tsai, Jack; Lydick, Jennifer M.
2010-01-01
Staff turnover on assertive community treatment (ACT) teams is a poorly understood phenomenon. This study examined annual turnover and fidelity data collected in a statewide implementation of ACT over a 5-year period. Mean annual staff turnover across all observations was 30.0%. Turnover was negatively correlated with overall fidelity at Year 1 and 3. The team approach fidelity item was negatively correlated with staff turnover at Year 3. For 13 teams with 3 years of follow-up data, turnover rates did not change over time. Most ACT staff turnover rates were comparable or better than other turnover rates reported in the mental health and substance abuse literature. PMID:20012481
Rollins, Angela L; Salyers, Michelle P; Tsai, Jack; Lydick, Jennifer M
2010-09-01
Staff turnover on assertive community treatment (ACT) teams is a poorly understood phenomenon. This study examined annual turnover and fidelity data collected in a statewide implementation of ACT over a 5-year period. Mean annual staff turnover across all observations was 30.0%. Turnover was negatively correlated with overall fidelity at Year 1 and 3. The team approach fidelity item was negatively correlated with staff turnover at Year 3. For 13 teams with 3 years of follow-up data, turnover rates did not change over time. Most ACT staff turnover rates were comparable or better than other turnover rates reported in the mental health and substance abuse literature.
Flagellar generated flow mediates attachment of Giardia lamblia
NASA Astrophysics Data System (ADS)
Urbach, Jeffrey; Luo, Haibei; Picou, Theodore; McAllister, Ryan; Elmendorf, Heidi
2011-03-01
Giardia lamblia is a protozoan parasite responsible for widespread diarrheal disease in humans and animals worldwide. Attachment to the host intestinal mucosa and resistance to peristalsis is necessary for establishing infection, but the physical basis for this attachment is poorly understood. We report results from TIRF and confocal fluorescence microscopy that demonstrate that the regular beating of the posterior flagella generate a flow through the ventral disk, a suction-cup shaped structure that is against the substrate during attachment. Finite element simulations are used to compare the negative pressure generated by the flow to the measured attachment force and the expected performance of the flagellar pump. NIH grant 1R21AI062934-0.
Perturbation of nucleo-cytoplasmic transport affects size of nucleus and nucleolus in human cells.
Ganguly, Abira; Bhattacharjee, Chumki; Bhave, Madhura; Kailaje, Vaishali; Jain, Bhawik K; Sengupta, Isha; Rangarajan, Annapoorni; Bhattacharyya, Dibyendu
2016-03-01
Size regulation of human cell nucleus and nucleolus are poorly understood subjects. 3D reconstruction of live image shows that the karyoplasmic ratio (KR) increases by 30-80% in transformed cell lines compared to their immortalized counterpart. The attenuation of nucleo-cytoplasmic transport causes the KR value to increase by 30-50% in immortalized cell lines. Nucleolus volumes are significantly increased in transformed cell lines and the attenuation of nucleo-cytoplasmic transport causes a significant increase in the nucleolus volume of immortalized cell lines. A cytosol and nuclear fraction swapping experiment emphasizes the potential role of unknown cytosolic factors in nuclear and nucleolar size regulation. © 2016 Federation of European Biochemical Societies.
Effects Of Crystallographic Properties On The Ice Nucleation Properties Of Volcanic Ash Particles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kulkarni, Gourihar R.; Nandasiri, Manjula I.; Zelenyuk, Alla
2015-04-28
Specific chemical and physical properties of volcanic ash particles that could affect their ability to induce ice formation are poorly understood. In this study, the ice nucleating properties of size-selected volcanic ash and mineral dust particles in relation to their surface chemistry and crystalline structure at temperatures ranging from –30 to –38 °C were investigated in deposition mode. Ice nucleation efficiency of dust particles was higher compared to ash particles at all temperature and relative humidity conditions. Particle characterization analysis shows that surface elemental composition of ash and dust particles was similar; however, the structural properties of ash samples weremore » different.« less
Microstructural and functional connectivity in the developing preterm brain
Lubsen, Julia; Vohr, Betty; Myers, Eliza; Hampson, Michelle; Lacadie, Cheryl; Schneider, Karen C.; Katz, Karol H.; Constable, R. Todd; Ment, Laura R.
2011-01-01
Prematurely born children are at increased risk for cognitive deficits, but the neurobiological basis of these findings remains poorly understood. Since variations in neural circuitry may influence performance on cognitive tasks, recent investigations have explored the impact of preterm birth on connectivity in the developing brain. Diffusion tensor imaging studies demonstrate widespread alterations in fractional anisotropy, a measure of axonal integrity and microstructural connectivity, throughout the developing preterm brain. Functional connectivity studies report that preterm neonates, children and adolescents exhibit alterations in both resting state and task-based connectivity when compared to term control subjects. Taken together, these data suggest that neurodevelopmental impairment following preterm birth may represent a disease of neural connectivity. PMID:21255705
Nurses' understanding influences comprehension of patients admitted in the observation unit.
Desme, Aline; Mendes, Nathalie; Perruche, Franck; Veillard, Elsa; Elie, Caroline; Moulinet, Françoise; Sanson, Fabienne; Georget, Jean-Michel; Tissier, Anne; Pourriat, Jean-Louis; Claessens, Yann-Erick
2013-01-01
Comprehension is poor in patients admitted in the emergency observation unit. Teamwork communication gaps could contribute to patients' misunderstanding of their health condition. To determine in patients admitted in the emergency observation unit whether comprehension of diagnosis, prognosis, and management depended on nurses' comprehension, the authors conducted a prospective observational study in a busy adult emergency department of a tertiary teaching hospital in Paris over 2 months. Consecutive patients admitted in the emergency observation unit were included. Patients' and nurses' comprehension of diagnosis, prognosis, and management was compared with the statements of the emergency department attending physicians for these items. The authors observed whether patients' misunderstanding was associated with nurses' misunderstanding. A total of 544 patients were evaluated. For each patient, nurses' and patients' comprehension was available. Patients understood severity in 40%, organ involved in 69%, medical wording in 57%, reason for admission in 48%, and discharge instruction in 67%. In comparison with patients, nurses better understood each item except for discharge instruction. The authors observed that patients' comprehension was better when nurses understood diagnosis (p <.0001), reasons for admission (p =.032) and discharge instructions (p =.002). Nurses' understanding of severity did not modify patients' comprehension. These results support the conclusions that communication gaps in teamwork alter patients' comprehension and that nurses' and patients' misunderstandings are associated. Therefore, improving communication by nurses and physicians to patients may improve patients' understanding.
Narayanan, Sathiya Pandi; Singh, Smriti; Gupta, Amit; Yadav, Sandhya; Singh, Shree Ram; Shukla, Sanjeev
2015-10-28
The histone demethylase KDM1A specifically demethylates lysine residues and its deregulation has been implicated in the initiation and progression of various cancers. However, KDM1A's molecular role and its pathological consequences, and prognostic significance in oral cancer remain less understood. In the present study, we sought to investigate the expression of KDM1A and its downstream role in oral cancer pathogenesis. By comparing mRNA expression profiles, we identified an elevated KDM1A expression in oral tumors when compared to normal oral tissues. In silico pathway prediction identified the association between KDM1A and E2F1 signaling in oral cancer. Pathway scanning, functional annotation analysis and In vitro assays showed the KDM1A's involvement in oral cancer cell proliferation and the cell cycle. Moreover, real time PCR and luciferase assays confirmed KDM1A's role in regulation of E2F1 signaling activity in oral cancer. Elevated KDM1A expression is associated with poor clinical outcome in oral cancer. Our data indicate that deregulated KDM1A expression is positively associated with proliferative phenotype of oral cancer and confers poor clinical outcome. These cumulative data suggest that KDM1A might be a potential diagnostic and therapeutic target for oral cancer. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Silva-Costa, Aline; Griep, Rosane Härter; Rotenberg, Lúcia
2015-01-01
Epidemiological evidence suggests that sleep duration and poor sleep are associated with mortality, as well as with a wide range of negative health outcomes. However, few studies have examined the association between sleep and self-rated health, particularly through the combination of sleep complaints. The objective of this study was to examine whether self-rated health is associated with sleep complaints, considering the combination of sleep duration, insomnia, and sleep sufficiency. This cross-sectional study was performed in the 18 largest public hospitals in the city of Rio de Janeiro, Brazil. A total of 2518 female nurses answered a self-filled multidimensional questionnaire. The adjusted odds ratios and 95% confidence intervals (CIs) estimated the chance of poor self-rated health in the presence of different combinations of sleep duration and quality. Compared with women who reported adequate sleep duration with no sleep quality complaints (reference group), the odds ratios (95% CI) for poor self-rated health were 1.79 (1.27-2.24) for those who reported only insufficient sleep, 1.85 (0.94-3.66) for only a short sleep duration, and 3.12 (1.94-5.01) for only insomnia. Compared with those who expressed all three complaints (short sleep duration, insomnia, and insufficient sleep), the odds ratio for poor self-rated health was 4.49 (3.25-6.22). Differences in the magnitude of the associations were observed, depending on the combination of sleep complaints. Because self-rated health is a consistent predictor of morbidity, these results reinforce the increasing awareness of the role of sleep in health and disease. Our findings contribute to the recognition of sleep as a public health matter that deserves to be better understood and addressed by policymakers.
Selective Neuronal Activation by Cochlear Implant Stimulation in Auditory Cortex of Awake Primate
Johnson, Luke A.; Della Santina, Charles C.
2016-01-01
Despite the success of cochlear implants (CIs) in human populations, most users perform poorly in noisy environments and music and tonal language perception. How CI devices engage the brain at the single neuron level has remained largely unknown, in particular in the primate brain. By comparing neuronal responses with acoustic and CI stimulation in marmoset monkeys unilaterally implanted with a CI electrode array, we discovered that CI stimulation was surprisingly ineffective at activating many neurons in auditory cortex, particularly in the hemisphere ipsilateral to the CI. Further analyses revealed that the CI-nonresponsive neurons were narrowly tuned to frequency and sound level when probed with acoustic stimuli; such neurons likely play a role in perceptual behaviors requiring fine frequency and level discrimination, tasks that CI users find especially challenging. These findings suggest potential deficits in central auditory processing of CI stimulation and provide important insights into factors responsible for poor CI user performance in a wide range of perceptual tasks. SIGNIFICANCE STATEMENT The cochlear implant (CI) is the most successful neural prosthetic device to date and has restored hearing in hundreds of thousands of deaf individuals worldwide. However, despite its huge successes, CI users still face many perceptual limitations, and the brain mechanisms involved in hearing through CI devices remain poorly understood. By directly comparing single-neuron responses to acoustic and CI stimulation in auditory cortex of awake marmoset monkeys, we discovered that neurons unresponsive to CI stimulation were sharply tuned to frequency and sound level. Our results point out a major deficit in central auditory processing of CI stimulation and provide important insights into mechanisms underlying the poor CI user performance in a wide range of perceptual tasks. PMID:27927962
Tracking contaminant flux from aquatic to terrestrial food webs
Aquatic insects provide a critical energy subsidy to riparian food webs, yet their role as vectors of contaminants to terrestrial ecosystems is poorly understood. We investigated aquatic resource utilization and contaminant exposure among riparian invertivores (spiders and herpt...
Asthma and Respiratory Allergic Disease
The pathogenesis of non-communicable diseases such as allergy is complex and poorly understood. The causes of chronic allergic diseases including asthma involve to a large extent, immunomodulation of the adaptive and particularly the innate immune systems and are markedly influen...
A Production Function Approach to Regional Environmental Economic Assessments
Regional-scale environmental assessments require integrating many available types of data having inconsistent spatial or temporal scales. Moreover, the relationships among the environmental variables in the assessment tend to be poorly understood, a situation made even more compl...
AtCHX13 is a plasma membrane K(+) transporter
USDA-ARS?s Scientific Manuscript database
Potassium (K+) homeostasis is essential for diverse cellular processes, although how various cation transporters collaborate to maintain a suitable K(+) required for growth and development is poorly understood. The Arabidopsis ("Arabidopsis thaliana") genome contains numerous cation:proton antiporte...
AtCHX13 is a plasma membrane K+ transporter
USDA-ARS?s Scientific Manuscript database
Potassium (K+) homeostasis is essential for diverse cellular processes, although how various cation transporters collaborate to maintain a suitable K+ required for growth and development is poorly understood. The Arabidopsis (Arabidopsis thaliana) genome contains numerous cation:proton antiporters (...
The 2011 National Wetland Condition Assessment
The ecological condition of wetland resources across the conterminous United States is poorly understood. To address this issue, the U.S. Environmental Protection Agency (USEPA), in collaboration with states, tribes, and other federal partners, is conducting the first-ever Natio...
AN IMPROVED METHOD FOR DETECTING VIRUSES IN WATER
Enteroviruses are important etiological agents of waterborne disease and are responsible for outbreaks of gastroenteritis. However, the prevalence and occurrence of these pathogens in raw drinking water sources is poorly understood. This is primarily due to the limited methods ...
The mechanisms of intrarenal hemodynamic changes following acute arterial occlusion.
DOT National Transportation Integrated Search
1963-10-01
The hemodynamic response of the kidney to acute arterial occlusion is poorly understood. The purpose of the present study was to determine intrarenal hemodynamic changes in intact and isolated kidneys following arterial occlusion. : The relative role...
Prediction of Membership in Rehabilitation Counseling Professional Associations
ERIC Educational Resources Information Center
Phillips, Brian N.; Leahy, Michael J.
2012-01-01
Declining membership is a concerning yet poorly understood issue affecting professional associations across disciplines (Bauman, 2008). Rehabilitation counseling association membership is in decline even while number of certified rehabilitation counselors continues to increase (Leahy, 2009). Factors influencing rehabilitation counseling…
The prevalence and causes of autistic spectrum disorders.
Hainsworth, Terry
Autism and autistic spectrum disorders are still relatively poorly understood. This article outlines the results of new research into the prevalence of autism and into the causes of the condition and highlights implications for nurses from the findings.
Familiarity and Aptness in Metaphor Comprehension.
Damerall, Alison Whiteford; Kellogg, Ronald T
2016-01-01
The career of metaphor hypothesis suggests that novel metaphors are understood through a search for shared features between the topic and vehicle, but with repeated exposure, the figurative meaning is understood directly as a new category is established. The categorization hypothesis argues that instead good or apt metaphors are understood through a categorization process, whether or not they are familiar. Only poor metaphors ever invoke a literal comparison. In Experiment 1, with aptness equated, we found that high familiarity speeded comprehension time over low-familiarity metaphors. In Experiment 2a, providing a literal prime failed to facilitate interpretation of low-familiarity metaphors, contrary to the career of metaphor hypothesis. In Experiment 2b, with familiarity equated, high- and low-aptness metaphors did not differ, contrary to the categorization hypothesis.
Loneliness in psychosis: a systematic review.
Lim, Michelle H; Gleeson, John F M; Alvarez-Jimenez, Mario; Penn, David L
2018-03-01
The aim of the review is to understand the relationships between loneliness and related psychological and social factors in individuals with psychosis. Loneliness is poorly understood in people with psychosis. Given the myriad of social challenges facing individuals with psychosis, these findings can inform psychosocial interventions that specifically target loneliness in this vulnerable group. We adhered to the PRISMA guidelines and systematically reviewed empirical studies that measured loneliness either as a main outcome or as an associated variable in individuals with psychosis. A total of ten studies examining loneliness in people diagnosed with a psychotic disorder were examined. Heterogeneity in the assessment of loneliness was found, and there were contradictory findings on the relationship between loneliness and psychotic symptomatology. In individuals with psychosis, loneliness may be influenced by psychological and social factors such as increased depression, psychosis, and anxiety, poor social support, poor quality of life, more severe internalised stigma and perceived discrimination, and low self-esteem. The relationship between loneliness and psychosis remains poorly understood due to a lack of rigorous studies. Although having strong social relationships is crucial to facilitate recovery from serious mental illness, psychosocial interventions that specifically target loneliness in individuals with psychosis are lacking and sorely needed. Interventions targeting loneliness in those with psychosis will also need to account for additional barriers associated with psychosis (e.g., social skill deficits, impoverished social networks, and negative symptoms).
Transcriptional markers of sub-optimal nutrition in developing Apis mellifera nurse workers
2014-01-01
Background Honey bees (Apis mellifera) contribute substantially to the worldwide economy and ecosystem health as pollinators. Pollen is essential to the bee’s diet, providing protein, lipids, and micronutrients. The dramatic shifts in physiology, anatomy, and behavior that accompany normal worker development are highly plastic and recent work demonstrates that development, particularly the transition from nurse to foraging roles, is greatly impacted by diet. However, the role that diet plays in the developmental transition of newly eclosed bees to nurse workers is poorly understood. To further understand honey bee nutrition and the role of diet in nurse development, we used a high-throughput screen of the transcriptome of 3 day and 8 day old worker bees fed either honey and stored pollen (rich diet) or honey alone (poor diet) within the hive. We employed a three factor (age, diet, age x diet) analysis of the transcriptome to determine whether diet affected nurse worker physiology and whether poor diet altered the developmental processes normally associated with aging. Results Substantial changes in gene expression occurred due to starvation. Diet-induced changes in gene transcription occurring in younger bees were largely a subset of those occurring in older bees, but certain signatures of starvation were only evident 8 day old workers. Of the 18,542 annotated transcripts in the A. mellifera genome, 150 transcripts exhibited differential expression due to poor diet at 3d of age compared with 17,226 transcripts that differed due to poor diet at 8d of age, and poor diet caused more frequent down-regulation of gene expression in younger bees compared to older bees. In addition, the age-related physiological changes that accompanied early adult development differed due to the diet these young adult bees were fed. More frequent down-regulation of gene expression was observed in developing bees fed a poor diet compared to those fed an adequate diet. Functional analyses also suggest that the physiological and developmental processes occurring in well-fed bees are vastly different than those occurring in pollen deprived bees. Our data support the hypothesis that poor diet causes normal age-related development to go awry. Conclusion Poor nutrition has major consequences for the expression of genes underlying the physiology and age-related development of nurse worker bees. More work is certainly needed to fully understand the consequences of starvation and the complex biology of nutrition and development in this system, but the genes identified in the present study provide a starting point for understanding the consequences of poor diet and for mitigating the economic costs of colony starvation. PMID:24529032
Continuous-variable quantum key distribution protocols over noisy channels.
García-Patrón, Raúl; Cerf, Nicolas J
2009-04-03
A continuous-variable quantum key distribution protocol based on squeezed states and heterodyne detection is introduced and shown to attain higher secret key rates over a noisy line than any other one-way Gaussian protocol. This increased resistance to channel noise can be understood as resulting from purposely adding noise to the signal that is converted into the secret key. This notion of noise-enhanced tolerance to noise also provides a better physical insight into the poorly understood discrepancies between the previously defined families of Gaussian protocols.
Understanding the linkage between the physicochemical (PC) properties of nanoparticles (NP) and their activation of biological systems is poorly understood, yet fundamental to predicting nanotoxicity, idenitifying mode of actions and developing appropriate and effective regul...
Physiological benefits of nectar-feeding by a predatory beetle
USDA-ARS?s Scientific Manuscript database
Extrafloral nectar is an important food source for many animals, including predatory lady beetles (Coleoptera: Coccinellidae), although the physiological benefits of nectar consumption are poorly understood for most consumers. Under laboratory conditions, we confined new females of Coleomegilla macu...
Fructose, high fructose corn syrup, sucrose, and non-alcoholic liver disease
USDA-ARS?s Scientific Manuscript database
Nonalcoholic fatty liver disease (NAFLD), formerly called nonalcoholic steatohepatitis, is characterized by hepatic steatosis and abnormal triglyceride accumulation in liver cells. Its etiology, pathophysiology, and pathogenesis are still poorly understood. Some have suggested that the increased in...
Salary, Performance, and Superintendent Turnover
ERIC Educational Resources Information Center
Grissom, Jason A.; Mitani, Hajime
2016-01-01
Purpose: Superintendent retention is an important goal for many school districts, yet the factors contributing to superintendent turnover are poorly understood. Most prior quantitative studies of superintendent turnover have relied on small, cross-sectional samples, limiting the evidence base. Utilizing longitudinal administrative records from…
New perspectives on microbial community distortion after whole-genome amplification
Whole-genome amplification (WGA) has become an important tool to explore the genomic information of microorganisms in an environmental sample with limited biomass, however potential selective biases during the amplification processes are poorly understood. Here, we describe the e...
Abbassian, Ali; Thomas, Rhidian
2008-06-01
Ankle ligament injuries in the presence or in the absence of fractures are common. They often present a diagnostic challenge, and their management is poorly understood and subject to debate. This article reviews and discusses the current literature on the management and diagnosis of these injuries.
NASA Technical Reports Server (NTRS)
Murphy, Kyle R.; Mann, Ian R.; Rae, I. Jonathan; Sibeck, David G.; Watt, Clare E. J.
2016-01-01
Wave-particle interactions play a crucial role in energetic particle dynamics in the Earths radiation belts. However, the relative importance of different wave modes in these dynamics is poorly understood. Typically, this is assessed during geomagnetic storms using statistically averaged empirical wave models as a function of geomagnetic activity in advanced radiation belt simulations. However, statistical averages poorly characterize extreme events such as geomagnetic storms in that storm-time ultralow frequency wave power is typically larger than that derived over a solar cycle and Kp is a poor proxy for storm-time wave power.
Li, Wanxin; Ali, Farman; Cai, Qilan; Yao, Zujie; Sun, Lina; Lin, Wenxiong; Lin, Xiangmin
2018-05-30
In recent years, Aeromonas hydrophila, which has been classified as a food borne pathogen, has presented with increased levels of antibiotic resistance, with the mechanisms of this resistance being poorly understood. In this study, iTRAQ coupled mass spectrometry was employed to compare differentially expressed proteins in chlortetracycline (CTC) resistant A. hydrophila relative to a control strain. Result showed that a total of 234 differential proteins including 151 down-regulated and 83 up-regulated were identified in chlortetracycline resistance strain. Bioinformatics analysis showed that chemotaxis related proteins, such as CheA-2, CheR-3, CheW-2, EnvZ, PolA, FliS and FliG were down-regulated in addition to previously reported tricarboxylic acid cycle (TCA) related proteins also being down-regulated. A subset of identified differentially expressed proteins was then further validated via Western blotting. Exogenous metabolite combined with CTC further enhanced the bacterial susceptibilities to CTC in A. hydrophila. Furthermore, a bacterial survival capability assay showed that several chemotaxis related mutants, such as ΔcheR-3 and ΔAHA_0305, may affect the antimicrobial susceptibility of A. hydrophila. Overall, these findings contribute to a further understanding of the mechanism of CTC resistance in A. hydrophila and may contribute to the development of more effective future treatments. A. hydrophila is a well-known fish pathogenic bacterium and has presented with increasing levels of antibiotic resistance, with the mechanisms of this resistance being poorly understood. Our current study compared the differentially expression proteins between chlortetracycline (CTC) resistant and control stains via an iTARQ-based quantitative proteomics method. Chemotaxis related proteins were down-regulated in CTC resistant strain but exogenous metabolite addition increased bacterial susceptibility in A.hydrophila. Significantly, chemotaxis related genes depletion affected antimicrobial susceptibilities of A.hydrophila indicating the role of chemotaxis process in antibiotics resistance. Copyright © 2018 Elsevier B.V. All rights reserved.
Brand, Serge; Kirov, Roumen; Kalak, Nadeem; Gerber, Markus; Pühse, Uwe; Lemola, Sakari; Correll, Christoph U; Cortese, Samuele; Meyer, Till; Holsboer-Trachsler, Edith
2015-01-01
Perfectionism is understood as a set of personality traits such as unrealistically high and rigid standards for performance, fear of failure, and excessive self-criticism. Previous studies showed a direct association between increased perfectionism and poor sleep, though without taking into account possible mediating factors. Here, we tested the hypothesis that perfectionism was directly associated with poor sleep, and that this association collapsed, if mediating factors such as stress and poor emotion regulation were taken into account. Three hundred and forty six young adult students (M=23.87 years) completed questionnaires relating to perfectionism traits, sleep, and psychological functioning such as stress perception, coping with stress, emotion regulation, and mental toughness. Perfectionism was directly associated with poor sleep and poor psychological functioning. When stress, poor coping, and poor emotion regulation were entered in the equation, perfectionism traits no longer contributed substantively to the explanation of poor sleep. Though perfectionism traits seem associated with poor sleep, the direct role of such traits seemed small, when mediating factors such as stress perception and emotion regulation were taken into account.
Brand, Serge; Kirov, Roumen; Kalak, Nadeem; Gerber, Markus; Pühse, Uwe; Lemola, Sakari; Correll, Christoph U; Cortese, Samuele; Meyer, Till; Holsboer-Trachsler, Edith
2015-01-01
Background Perfectionism is understood as a set of personality traits such as unrealistically high and rigid standards for performance, fear of failure, and excessive self-criticism. Previous studies showed a direct association between increased perfectionism and poor sleep, though without taking into account possible mediating factors. Here, we tested the hypothesis that perfectionism was directly associated with poor sleep, and that this association collapsed, if mediating factors such as stress and poor emotion regulation were taken into account. Methods Three hundred and forty six young adult students (M=23.87 years) completed questionnaires relating to perfectionism traits, sleep, and psychological functioning such as stress perception, coping with stress, emotion regulation, and mental toughness. Results Perfectionism was directly associated with poor sleep and poor psychological functioning. When stress, poor coping, and poor emotion regulation were entered in the equation, perfectionism traits no longer contributed substantively to the explanation of poor sleep. Conclusion Though perfectionism traits seem associated with poor sleep, the direct role of such traits seemed small, when mediating factors such as stress perception and emotion regulation were taken into account. PMID:25678791
Taylor, Cliff D.; Giles, Stuart A.
2015-01-01
USGS review of PRISM-I data suggests that there is abundant documentation of the Bou Naga alkaline complex and to a lesser degree, the Guelb er Richat carbonatite complex, but that all other occurrences of U, Th, REE, and associated elements are poorly described, and poorly understood (Taylor, 2007)
Atherosclerosis associated with pericardial effusion in a central bearded dragon (Pogona vitticeps).
Schilliger, Lionel; Lemberger, Karin; Chai, Norin; Bourgeois, Aude; Charpentier, Maud
2010-09-01
Atherosclerosis is a common disease in pet birds, particularly in psittacines, and is frequently found when performing postmortem examinations on adult and old dogs, in which it is mainly associated with endocrine diseases, such as hypothyroidism and diabetes mellitus. However, atherosclerosis is poorly documented in reptiles and consequently poorly understood. In the current case report, atherosclerosis and pericardial effusion were diagnosed in a 2-year-old male central bearded dragon (Pogona vitticeps) based on ultrasound visualization, necropsy, and histologic examination.
USING MOLECULAR PROBES TO STUDY INTERFACIAL REDOX REACTION AT FE-BEARING SMECTITES
The interfacial electron transfer of clay-water systems has a wide range of significance in geochemical and biogeochernical environments. However the mechanism of interfacial electron transport is poorly understood. The electron transfer mechanism at the solid-water interfaces of...
Larval fish distribution in the St. Louis River estuary
Our objective was to determine what study design, environmental, and habitat variables contribute to the distribution and abundance of larval fish in the St. Louis River estuary. Larval fish habitat associations are poorly understood in Great Lakes coastal wetlands, yet critical ...
Post-traumatic unilateral plantar hyperhidrosis.
Eren, Y; Yavasoglu, N G; Comoglu, S S
2016-02-01
Localized unilateral hyperhidrosis is rare and poorly understood, sometimes stemming from trauma. Feet, quite vulnerable to trauma are affected by disease-mediated plantar hyperhidrosis, usually bilaterally. This report describes partial hyperhidrosis developing post-traumatically on the left plantar region of a 52-year-old male.
Predator-prey interaction reveals local effects of high-altitude insect migration
USDA-ARS?s Scientific Manuscript database
High-altitude nocturnal insect migrations represent significant pulses of resources, yet are difficult to study and poorly understood. Predator-prey interactions, specifically migratory moth consumption by high-flying bats, potentially reveal flows of migratory insects across a landscape. In North...
Assessing Effects of Pesticides on the Bee Immune System
Populations of some managed and wild pollinators are in decline as a result of multiple interacting factors including parasites, disease, poor nutrition and pesticides. The role that diminished immunity plays in these declines is not understood. The U.S. Environmental Protection ...
USDA-ARS?s Scientific Manuscript database
Colony development, which includes hyphal extension, branching, anastomosis and asexual sporulation are fundamental aspects of the lifecycle of filamentous fungi; genetic mechanisms underlying these phenomena are poorly understood. We conducted transcriptional profiling during colony development of...
USEPA RESEARCH ON FISH - HABITAT RELATIONSHIPS IN GREAT LAKES COASTAL MARSHES
Despite numerous studies documenting fish use of particular habitat elements, the role of habitat mosaics in supporting wetland fishes is poorly understood. USEPA's Mid-Continent Ecology Division has initiated research to identify relationships of fish and habitat in coastal mars...
A Cellular Game of Telephone: Trans Tissue Reprogramming of Responses to Toxic Stimuli
Exposure to air pollution is a leading cause of cardiopulmonary morbidity and mortality; however, while these effects outside the lung have been associated with aberrant oxidative stress and inflammation, the underlying molecular mechanisms are poorly understood. We hypothesized ...
Cellular Plasticity in the Diabetic Myocardium
2017-09-01
demonstrated that obese diabetic db/db mice in a C57Bl6J background exhibit cardiac remodeling, associated with modest ventricular dilation...HFpEF, the cellular basis for fibrotic remodeling of the ventricle is poorly understood. Metabolic diseases (such as obesity and diabetes) are
Reduce Confusion about Diffusion.
ERIC Educational Resources Information Center
Hebrank, Mary R.
1997-01-01
Presents activities that allow students to explore the fundamental but poorly understood concept of diffusion by appealing to their kinesthetic senses first, then challenging their analytical skills as they try to deduce the mathematical principle involved. Presents a computer simulation of diffusion and discusses diffusion's limitations and…
INTERNATIONAL CHILDHOOD CANCER COHORT CONSORTIUM (Journal Article)
Childhood cancers are rare conditions whose etiology is poorly understood. There is evidence that for some, the causal pathway may commence in utero or during peri-conception. One traditional epidemiologic approach to the study of rare diseases is the use of a retrospective cas...
A Multilevel Investigation of Neighborhood Effects on Parental Warmth
ERIC Educational Resources Information Center
Tendulkar, Shalini A.; Buka, Stephen; Dunn, Erin C.; Subramanian, S. V.; Koenen, Karestan C.
2010-01-01
Although researchers recognize that social contexts shape parenting behaviors, the relationship between neighborhood environment and parenting remains poorly understood. To address this gap, we investigated the associations between compositional and contextual (structural, social, and safety) characteristics of neighborhoods and parental warmth.…
Origins of Brain Tumor Macrophages.
De Palma, Michele
2016-12-12
The ontogeny of brain-tumor-associated macrophages is poorly understood. New findings indicate that both resident microglia and blood-derived monocytes generate the pool of macrophages that infiltrate brain tumors of either primary or metastatic origin. Copyright © 2016 Elsevier Inc. All rights reserved.
Pollinator guilds respond differently to urban habitat fragmentation in a oak-savannah ecosystem
USDA-ARS?s Scientific Manuscript database
Habitat fragmentation is widely thought to threaten biodiversity. However, response of pollinators to habitat fragmentation is still poorly understood, as pollinator communities are notoriously spatially variable. We investigated pollinator community structure in a highly fragmented oak-savannah ec...
Wetland creation, enhancement, and restoration activities are commonly implemented to compensate for wetland loss or degradation. However, functional equivalence in restored and created wetland habitats is often poorly understood. In estuarine habitats, changes in habitat qualit...
Ozone-Induced Metabolic Impairment is Attenuated in Adrenalectomized Wistar Kyoto Rats
Rationale: Air pollutants have been linked to increased incidence of metabolic syndrome however the mechanisms are poorly understood. We have recently shown that ozone exposure induces significant hyperglycemia together with elevated serum leptin and epinephrine in the Wistar Ky...
THE INTERACTION OF VAPOUR PHASE ORGANIC COMPOUNDS WITH INDOOR SINKS
The interaction of indoor air pollutants with interior surfaces (i.e., sinks) is a well known, but poorly understood, phenomenon. Studies have shown that re-emissions of adsorbed organic vapours can contribute to elevated concentrations of organics in indoor environments. Researc...
Preschool Executive Functioning Abilities Predict Early Mathematics Achievement
ERIC Educational Resources Information Center
Clark, Caron A. C.; Pritchard, Verena E.; Woodward, Lianne J.
2010-01-01
Impairments in executive function have been documented in school-age children with mathematical learning difficulties. However, the utility and specificity of preschool executive function abilities in predicting later mathematical achievement are poorly understood. This study examined linkages between children's developing executive function…
HYDRAULIC REDISTRIBUTION IN THE PACIFIC NORTHWEST: TWEAKING THE SYSTEM
Hydraulic redistribution (HR) has recently been documented in Pacific Northwest forests, but the controls governing this process and its importance to shallow-rooted species are poorly understood. Our objective in this study was to manipulate the soil-root system to tease apart ...
Pistole, David H; Peles, John D; Taylor, Kelly
2008-07-01
Understanding the effects of chemical toxicants on energetic processes is an important aspect of ecotoxicology. However, the influence of toxicant concentration and time of exposure on metabolism in aquatic organisms is still poorly understood. The purpose of this investigation was to determine the influence of increasing levels of three stressors (Cu, Cd, percent salinity) and exposure time (24 h and 96 h) on the metabolic rate of fathead minnows (Pimephales promelas). In all 24-h exposures, there existed a threshold concentration, above which metabolic rate decreased significantly compared to the control and lower concentrations. In contrast, the metabolic rate of fish exposed for 96 h increased significantly in all concentrations compared to fish from the control. We suggest fathead minnows exhibit a consistent pattern of metabolic response to stressors, regardless of the physiological mechanisms involved, and that this response differs as a function of time of exposure.
Human 3D vascularized organotypic microfluidic assays to study breast cancer cell extravasation
Jeon, Jessie S.; Bersini, Simone; Gilardi, Mara; Dubini, Gabriele; Charest, Joseph L.; Moretti, Matteo; Kamm, Roger D.
2015-01-01
A key aspect of cancer metastases is the tendency for specific cancer cells to home to defined subsets of secondary organs. Despite these known tendencies, the underlying mechanisms remain poorly understood. Here we develop a microfluidic 3D in vitro model to analyze organ-specific human breast cancer cell extravasation into bone- and muscle-mimicking microenvironments through a microvascular network concentrically wrapped with mural cells. Extravasation rates and microvasculature permeabilities were significantly different in the bone-mimicking microenvironment compared with unconditioned or myoblast containing matrices. Blocking breast cancer cell A3 adenosine receptors resulted in higher extravasation rates of cancer cells into the myoblast-containing matrices compared with untreated cells, suggesting a role for adenosine in reducing extravasation. These results demonstrate the efficacy of our model as a drug screening platform and a promising tool to investigate specific molecular pathways involved in cancer biology, with potential applications to personalized medicine. PMID:25524628
Matsui, Mariko; Roche, Louise; Soupé-Gilbert, Marie-Estelle; Hasan, Milena; Monchy, Didier; Goarant, Cyrille
2017-08-01
Leptospirosis is a severe zoonosis which immunopathogenesis is poorly understood. We evaluated correlation between acute form of the disease and the ratio of the anti-inflammatory cytokine IL-10 to the pro-inflammatory TNF-α and IL-1β expression during the early phase of infection comparing resistant mice and susceptible hamsters infected with two different species of virulent Leptospira. The IL-10/TNF-α and IL-10/IL-1β expression ratios were higher in mouse compared to hamster independently of the Leptospira strain, suggesting a preponderant role of the host response and notably these cytokines in the clinical expression and survival to leptospirosis. Using an IL-10 neutralization strategy in Leptospira-infected mouse model, we also showed evidence of a possible role of this cytokine on host susceptibility, bacterial clearance and on regulation of cytokine gene expression. Copyright © 2017 Elsevier Ltd. All rights reserved.
Human 3D vascularized organotypic microfluidic assays to study breast cancer cell extravasation.
Jeon, Jessie S; Bersini, Simone; Gilardi, Mara; Dubini, Gabriele; Charest, Joseph L; Moretti, Matteo; Kamm, Roger D
2015-01-06
A key aspect of cancer metastases is the tendency for specific cancer cells to home to defined subsets of secondary organs. Despite these known tendencies, the underlying mechanisms remain poorly understood. Here we develop a microfluidic 3D in vitro model to analyze organ-specific human breast cancer cell extravasation into bone- and muscle-mimicking microenvironments through a microvascular network concentrically wrapped with mural cells. Extravasation rates and microvasculature permeabilities were significantly different in the bone-mimicking microenvironment compared with unconditioned or myoblast containing matrices. Blocking breast cancer cell A3 adenosine receptors resulted in higher extravasation rates of cancer cells into the myoblast-containing matrices compared with untreated cells, suggesting a role for adenosine in reducing extravasation. These results demonstrate the efficacy of our model as a drug screening platform and a promising tool to investigate specific molecular pathways involved in cancer biology, with potential applications to personalized medicine.
ABCB1 identifies a subpopulation of uveal melanoma cells with high metastatic propensity
Landreville, Solange; Agapova, Olga A.; Kneass, Zachary T.; Salesse, Christian; Harbour, J. William
2011-01-01
SUMMARY Metastasis of tumor cells to distant organs is the leading cause of death in melanoma. Yet, the mechanisms of metastasis remain poorly understood. One key question is whether all cells in a primary tumor are equally likely to metastasize or whether subpopulations of cells preferentially give rise to metastases. Here, we identified a subpopulation of uveal melanoma cells expressing the multidrug resistance transporter ABCB1 that are highly metastatic compared to ABCB1− bulk tumor cells. ABCB1+ cells also exhibited enhanced clonogenicity, anchorage independent growth, tumorigenicity and mitochondrial activity compared to ABCB1− cells. A375 cutaneous melanoma cells contained a similar subpopulation of highly metastatic ABCB1+ cells. These findings suggest that some uveal melanoma cells have greater potential for metastasis than others, and that a better understanding of such cells may be necessary for more successful therapies for metastatic melanoma. PMID:21575142
Rodrigo, María José; Padrón, Iván; de Vega, Manuel; Ferstl, Evelyn
2018-03-01
Adolescents' neural substrates of emotional reactions to the consequences of risky decisions are poorly understood. In this functional magnetic resonance imaging study, 30 late adolescents and 30 young adults made risky and neutral decisions in social scenarios and received valenced outcomes. Negative outcomes in risky decisions eliciting regret, as compared with negative outcomes in neutral decisions eliciting disappointment, activated executive control (orbitofrontal cortex) and self-relevance regions (middle temporal gyrus [MTG], posterior cingulate cortex, and precuneus) for both age groups. Young adults showed more activation than adolescents in regret and disappointment as compared with relief and elation conditions in the avoidance (insula), action monitoring (inferior frontal gyrus, pre-SMA, and caudate), and social-cognition regions (superior temporal sulcus and MTG). These late socio-emotional developments may pave the way for more adaptive decision-making behavior in social contexts. © 2018 Society for Research on Adolescence.
Foffa, Davide; Cuff, Andrew R; Sassoon, Judyth; Rayfield, Emily J; Mavrogordato, Mark N; Benton, Michael J
2014-08-01
Pliosaurs were among the largest predators in Mesozoic seas, and yet their functional anatomy and feeding biomechanics are poorly understood. A new, well-preserved pliosaur from the Kimmeridgian of Weymouth Bay (UK) revealed cranial adaptations related to feeding. Digital modelling of computed tomography scans allowed reconstruction of missing, distorted regions of the skull and of the adductor musculature, which indicated high bite forces. Size-corrected beam theory modelling showed that the snout was poorly optimised against bending and torsional stresses compared with other aquatic and terrestrial predators, suggesting that pliosaurs did not twist or shake their prey during feeding and that seizing was better performed with post-symphyseal bites. Finite element analysis identified biting-induced stress patterns in both the rostrum and lower jaws, highlighting weak areas in the rostral maxillary-premaxillary contact and the caudal mandibular symphysis. A comparatively weak skull coupled with musculature that was able to produce high forces, is explained as a trade-off between agility, hydrodynamics and strength. In the Kimmeridgian ecosystem, we conclude that Late Jurassic pliosaurs were generalist predators at the top of the food chain, able to prey on reptiles and fishes up to half their own length. © 2014 Anatomical Society.
Foffa, Davide; Cuff, Andrew R; Sassoon, Judyth; Rayfield, Emily J; Mavrogordato, Mark N; Benton, Michael J
2014-01-01
Pliosaurs were among the largest predators in Mesozoic seas, and yet their functional anatomy and feeding biomechanics are poorly understood. A new, well-preserved pliosaur from the Kimmeridgian of Weymouth Bay (UK) revealed cranial adaptations related to feeding. Digital modelling of computed tomography scans allowed reconstruction of missing, distorted regions of the skull and of the adductor musculature, which indicated high bite forces. Size-corrected beam theory modelling showed that the snout was poorly optimised against bending and torsional stresses compared with other aquatic and terrestrial predators, suggesting that pliosaurs did not twist or shake their prey during feeding and that seizing was better performed with post-symphyseal bites. Finite element analysis identified biting-induced stress patterns in both the rostrum and lower jaws, highlighting weak areas in the rostral maxillary-premaxillary contact and the caudal mandibular symphysis. A comparatively weak skull coupled with musculature that was able to produce high forces, is explained as a trade-off between agility, hydrodynamics and strength. In the Kimmeridgian ecosystem, we conclude that Late Jurassic pliosaurs were generalist predators at the top of the food chain, able to prey on reptiles and fishes up to half their own length. PMID:24925465
How atypical is atypical language dominance?
Knecht, S; Jansen, A; Frank, A; van Randenborgh, J; Sommer, J; Kanowski, M; Heinze, H J
2003-04-01
Atypical, right-hemisphere language dominance is poorly understood. It is often observed in patients with brain reorganization due to lesions early in life. It can also be encountered in seemingly normal individuals. We compared the patterns of neural language activation in 7 individuals with left- and 7 with right-hemisphere language dominance, none of whom had any evidence of brain lesions. We speculated that incongruencies in the activation patterns in atypical, right-hemisphere language dominance could indicate a reorganized neural language system after undetected early brain damage. Functional magnetic resonance imaging analysis of brain activation during phonetic word generation demonstrated (1). no increased activation in the subdominant hemisphere in right compared to left language dominance, (2). a similar variability in the pattern of activation in both groups, and (3). a mirror reverse pattern of activation in right- compared to left-hemisphere dominant subjects. These findings support the view that in individuals with an unrevealing medical history right-hemispheric dominance constitutes a natural rather than an abortive variant of language lateralization.
Atomic-scale dynamics of edge dislocations in Ni and concentrated solid solution NiFe alloys
Zhao, Shijun; Osetsky, Yuri N.; Zhang, Yanwen; ...
2017-01-19
Single-phase concentrated solid solution alloys (CSAs), including high entropy alloys, exhibit excellent mechanical properties compared to conventional dilute alloys. However, the origin of this observation is not clear yet because the dislocation properties in CSAs are poorly understood. In this work, the mobility of a <110>{111} edge dislocation in pure Ni and equiatomic solid solution Ni 0.5Fe 0.5 (NiFe) is studied using molecular dynamics simulations with different empirical potentials. The threshold stress to initiate dislocation movement in NiFe is found to be much higher compared to pure Ni. The drag coefficient of the dislocation motion calculated from the linear regimemore » of dislocation velocities versus applied stress suggests that the movement of dislocations in NiFe is strongly damped compared to that in Ni. The present results indicate that the mobility of edge dislocations in fcc CSAs are controlled by the fluctuations in local stacking fault energy caused by the local variation of alloy composition.« less
Her versus his migraine: multiple sex differences in brain function and structure
Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David
2012-01-01
Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a ‘sex phenotype’ in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs. PMID:22843414
Her versus his migraine: multiple sex differences in brain function and structure.
Maleki, Nasim; Linnman, Clas; Brawn, Jennifer; Burstein, Rami; Becerra, Lino; Borsook, David
2012-08-01
Migraine is twice as common in females as in males, but the mechanisms behind this difference are still poorly understood. We used high-field magnetic resonance imaging in male and female age-matched interictal (migraine free) migraineurs and matched healthy controls to determine alterations in brain structure. Female migraineurs had thicker posterior insula and precuneus cortices compared with male migraineurs and healthy controls of both sexes. Furthermore, evaluation of functional responses to heat within the migraine groups indicated concurrent functional differences in male and female migraineurs and a sex-specific pattern of functional connectivity of these two regions with the rest of the brain. The results support the notion of a 'sex phenotype' in migraine and indicate that brains are differentially affected by migraine in females compared with males. Furthermore, the results also support the notion that sex differences involve both brain structure as well as functional circuits, in that emotional circuitry compared with sensory processing appears involved to a greater degree in female than male migraineurs.
Convergence in Multispecies Interactions.
Bittleston, Leonora S; Pierce, Naomi E; Ellison, Aaron M; Pringle, Anne
2016-04-01
The concepts of convergent evolution and community convergence highlight how selective pressures can shape unrelated organisms or communities in similar ways. We propose a related concept, convergent interactions, to describe the independent evolution of multispecies interactions with similar physiological or ecological functions. A focus on convergent interactions clarifies how natural selection repeatedly favors particular kinds of associations among species. Characterizing convergent interactions in a comparative context is likely to facilitate prediction of the ecological roles of organisms (including microbes) in multispecies interactions and selective pressures acting in poorly understood or newly discovered multispecies systems. We illustrate the concept of convergent interactions with examples: vertebrates and their gut bacteria; ectomycorrhizae; insect-fungal-bacterial interactions; pitcher-plant food webs; and ants and ant-plants. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tidal Forces as Drivers of Collisional Evolution
NASA Technical Reports Server (NTRS)
Asphaug, E.; Agnor, C.; Williams, Q.
2005-01-01
Planetary collisions are usually understood as shock-related phenomena, analogous to impact cratering. But at large scales, where the impact timescale is comparable to the gravitational timescale, collisions can be dominated by gravitational torques and disruptive tides. Shock physics fares poorly, in many respects, in explaining asteroid and meteorite genesis. Melts, melt residues, welded agglomerates and hydrous and gasrich phases among meteorites lead to an array of diverse puzzles whose solution might be explained, in part, by the thermomechanics of tidal unloading. Comet Shoemaker-Levy 9 disrupted in a process that is common in the present and ancestral solar system, so here we consider specific effects tidal disruption had on the evolution of asteroids, comets and meteorites the unaccreted residues of planet formation.
Reassessing Immune Control of Hepatitis A Virus
Walker, Christopher M.; Feng, Zongdi; Lemon, Stanley M.
2015-01-01
There is renewed interest in hepatitis A virus (HAV) pathogenesis and immunity after 2–3 decades of limited progress. From a public health perspective, the average age at infection has increased in developing countries, resulting in more severe hepatitis that is poorly understood mechanistically. More fundamentally, there is interest in comparing immunity to HAV and hepatitis C virus (HCV): small, positive-strand RNA viruses with very different infection outcomes. Here, we review evidence that circulating HAV virions are cloaked in membranes, with consequences for induction of innate immunity and antibody-mediated neutralization. We also consider the contribution of CD4+ helper versus CD8+ cytotoxic T cells to antiviral immunity and liver injury, and present a model of non-cytotoxic immune control of HAV infection. PMID:25617494
Human casualties in earthquakes: Modelling and mitigation
Spence, R.J.S.; So, E.K.M.
2011-01-01
Earthquake risk modelling is needed for the planning of post-event emergency operations, for the development of insurance schemes, for the planning of mitigation measures in the existing building stock, and for the development of appropriate building regulations; in all of these applications estimates of casualty numbers are essential. But there are many questions about casualty estimation which are still poorly understood. These questions relate to the causes and nature of the injuries and deaths, and the extent to which they can be quantified. This paper looks at the evidence on these questions from recent studies. It then reviews casualty estimation models available, and finally compares the performance of some casualty models in making rapid post-event casualty estimates in recent earthquakes.
GABAergic anxiolytic drug in water increases migration behaviour in salmon
NASA Astrophysics Data System (ADS)
Hellström, Gustav; Klaminder, Jonatan; Finn, Fia; Persson, Lo; Alanärä, Anders; Jonsson, Micael; Fick, Jerker; Brodin, Tomas
2016-12-01
Migration is an important life-history event in a wide range of taxa, yet many migrations are influenced by anthropogenic change. Although migration dynamics are extensively studied, the potential effects of environmental contaminants on migratory physiology are poorly understood. In this study we show that an anxiolytic drug in water can promote downward migratory behaviour of Atlantic salmon (Salmo salar) in both laboratory setting and in a natural river tributary. Exposing salmon smolt to a dilute concentration of a GABAA receptor agonist (oxazepam) increased migration intensity compared with untreated smolt. These results implicate that salmon migration may be affected by human-induced changes in water chemical properties, such as acidification and pharmaceutical residues in wastewater effluent, via alterations in the GABAA receptor function.
The influence of spatial processes on population dynamics within river-stream networks is poorly understood. Utilizing spatially explicit analyses of temporal genetic variance, we examined whether persistence of Central Stonerollers (Campostoma anomalum) reflects differences in h...
Worldwide patterns of ancestry, divergence, and admixture in domesticated cattle
USDA-ARS?s Scientific Manuscript database
The domestication and development of cattle has considerably impacted human societies, but the histories of cattle breeds have been poorly understood especially for African, Asian, and American breeds. Using genotypes from 43,043 autosomal single nucleotide polymorphism markers scored in 1,543 anima...
ERIC Educational Resources Information Center
Blystone, Robert V.; Blodgett, Kevin
2006-01-01
The scientific method is the principal methodology by which biological knowledge is gained and disseminated. As fundamental as the scientific method may be, its historical development is poorly understood, its definition is variable, and its deployment is uneven. Scientific progress may occur without the strictures imposed by the formal…
From Movements to Actions: Two Mechanisms for Learning Action Sequences
ERIC Educational Resources Information Center
Endress, Ansgar D.; Wood, Justin N.
2011-01-01
When other individuals move, we interpret their movements as discrete, hierarchically-organized, goal-directed actions. However, the mechanisms that integrate visible movement features into actions are poorly understood. Here, we consider two sequence learning mechanisms--transitional probability-based (TP) and position-based encoding…
Accumulation of the Antibiotic Phenazine-1-Carboxylic Acid in the Rhizosphere of Dryland Cereals
USDA-ARS?s Scientific Manuscript database
Natural antibiotics are thought to function in the defense, fitness, competitiveness, biocontrol activity, communication and gene regulation of microorganisms. However, the scale and quantitative aspects of antibiotic production in natural settings are poorly understood. We addressed these fundament...
Background/Questions/Methods Large-bodied invertebrates (bivalves, polychaetes, burrowing shrimps) are common to infaunal communities of NE Pacific estuaries, but their contribution to estuarine community structure, function and ecosystem services is poorly understood because ...
Olfactory disruption: towards controlling important insect vectors of disease
USDA-ARS?s Scientific Manuscript database
Chemical repellents are used to decrease contacts between insect disease vectors and their hosts, thus reducing the probability of disease transmission. The molecular mechanisms by which repellents have their effects are poorly understood and remain a controversial topic. Here we present recent re...
USDA-ARS?s Scientific Manuscript database
Environmental enteric dysfunction (EED), a condition characterized by small intestine inflammation and abnormal gut permeability, is widespread in children in developing countries and a major cause of growth failure. The pathophysiology of EED remains poorly understood. We measured serum metabolite...
LOCAL VS. REGIONAL EFFECTS ON FISH DIVERSITY AS MEDIATED BY STREAMFLOW DISTURBANCE REGIME
abstract
The interplay of local and regional processes on fish diversity is poorly understood, especially related to patterns of streamflow disturbance regime. Articulation of the relationship between flow disturbance patterns and river fishes across local to regional scal...
USDA-ARS?s Scientific Manuscript database
Virtually every mammalian cell, including cardiomyocytes, possesses an intrinsic circadian clock. The role of this transcriptionally based molecular mechanism in cardiovascular biology is poorly understood. We hypothesized that the circadian clock within the cardiomyocyte influences diurnal variatio...
The role of methionine metabolism in inflammatory bowel disease
USDA-ARS?s Scientific Manuscript database
Methionine (Met) cycle activity is critical for normal cell functions. Met metabolites S-adenosylmethionine (SAM) and methylthioadenosine (MTA) are anti-inflammatory, yet their role in inflammatory bowel disease (IBD) is poorly understood. We hypothesize that active IBD leads to changes in Met metab...
Molecular basis for the thermostability of Newcastle disease virus
USDA-ARS?s Scientific Manuscript database
Thermostable Newcastle disease virus (NDV) vaccines have been used widely to protect village chickens against Newcastle disease, due to their decreased dependence on cold chain for transport and storage. However, the genetic basis underlying the NDV thermostability is poorly understood. In this stud...
Development and preliminary validation of the Parenting around SNAcking Questionnaire (P-SNAQ)
USDA-ARS?s Scientific Manuscript database
Snacking makes significant contributions to children's dietary intake but is poorly understood from a parenting perspective. This research was designed to develop and evaluate the psychometrics of a theoretically grounded, empirically-informed measure of snack parenting. The Parenting around SNAckin...
Do boll weevils really diapause?
USDA-ARS?s Scientific Manuscript database
Boll weevil, Anthonomus grandis grandis Boheman, diapause has been poorly understood since the term was first used 50 yrs ago to describe the pest’s winter dormancy in temperate regions. This literature-based study found that low temperature and changes in photoperiod are the boll weevil diapause-i...
Effects of exurban development on trophic interactions in a desert landscape
USDA-ARS?s Scientific Manuscript database
Context Mechanisms of ecosystem change in urbanizing landscapes are poorly understood, especially in exurban areas featuring residential or commercial development set in a matrix of modified and natural vegetation. We asked how development altered trophic interactions and ecosystem processes in the ...
Secondary organic aerosol (SOA) might affect the atmospheric radiation balance through absorbing light at shorter visible and UV wavelengths. However, the composition and optical properties of light-absorbing SOA is poorly understood. In this work, SOA filter samples were collect...
Reproductive responses of northern goshawks to variable prey populations
Susan R. Salafsky; Richard T. Reynolds; Barry R. Noon; John A. Wiens
2007-01-01
Developing comprehensive conservation strategies requires knowledge of factors influencing population growth and persistence. Although variable prey resources are often associated with fluctuations in raptor demographic parameters, the mechanisms of food limitation are poorly understood, especially for a generalist predator like the northern goshawk (Accipiter...
Aquatic insects provide a critical nutrient subsidy to riparian food webs, yet their role as vectors of contaminants to terrestrial ecosystems is poorly understood. We investigated relationships between aquatic (resource utilization) and contaminant exposure for a riparian invert...
The geography of spatial synchrony
Jonathan A. Walter; Lawrence W. Sheppard; Thomas L. Anderson; Jude H. Kastens; Ottar N. Bjørnstad; Andrew M. Liebhold; Daniel C. Reuman; Bernd Blasius
2017-01-01
Spatial synchrony, defined as correlated temporal fluctuations among populations, is a fundamental feature of population dynamics, but many aspects of synchrony remain poorly understood. Few studies have examined detailed geographical patterns of synchrony; instead most focus on how synchrony declines with increasing linear distance between locations, making the...
Heredity Factors in Spatial Visualization.
ERIC Educational Resources Information Center
Vandenberg, S. G.
Spatial visualization is not yet clearly understood. Some researchers have concluded that two factors or abilities are involved, spatial orientation and spatial visualization. Different definitions and different tests have been proposed for these two abilities. Several studies indicate that women generally perform more poorly on spatial tests than…
ERIC Educational Resources Information Center
Brock, David
2009-01-01
Despite student interest, the heart is often a poorly understood topic in biology. To help students understand this vital organ's physiology, the author created this investigation activity involving the mammalian heart and its role in the circulatory system. Students design, build, and demonstrate working artificial "hearts" to exhibit what they…
ERIC Educational Resources Information Center
Harrow, Chris; Chin, Lillian
2014-01-01
Exploration, innovation, proof: For students, teachers, and others who are curious, keeping an open mind and being ready to investigate unusual or unexpected properties will always lead to learning something new. Technology can further this process, allowing various behaviors to be analyzed that were previously memorized or poorly understood. This…
Multi-scale assessment of human-induced changes to Amazonian instream habitats
Context: Land use change and forest degradation have myriad effects on tropical ecosystems. Yet their consequences for low-order streams remain very poorly understood, including in the world´s largest freshwater basin, the Amazon.Objectives: Determine the degree to which ph...
Child stunting is associated with low circulating essential amino acids
USDA-ARS?s Scientific Manuscript database
Stunting affects about one-quarter of children under five worldwide. The pathogenesis of stunting is poorly understood. Nutritional interventions have had only modest effects in reducing stunting. We hypothesized that insufficiency in essential amino acids may be limiting the linear growth of childr...
Introduction to the Thematic Minireview Series: Brain glycogen metabolism.
Carlson, Gerald M; Dienel, Gerald A; Colbran, Roger J
2018-05-11
The synthesis of glycogen allows for efficient intracellular storage of glucose molecules in a soluble form that can be rapidly released to enter glycolysis in response to energy demand. Intensive studies of glucose and glycogen metabolism, predominantly in skeletal muscle and liver, have produced innumerable insights into the mechanisms of hormone action, resulting in the award of several Nobel Prizes over the last one hundred years. Glycogen is actually present in all cells and tissues, albeit at much lower levels than found in muscle or liver. However, metabolic and physiological roles of glycogen in other tissues are poorly understood. This series of Minireviews summarizes what is known about the enzymes involved in brain glycogen metabolism and studies that have linked glycogen metabolism to multiple brain functions involving metabolic communication between astrocytes and neurons. Recent studies unexpectedly linking some forms of epilepsy to mutations in two poorly understood proteins involved in glycogen metabolism are also reviewed. © 2018 Carlson et al.
Immigrant dairy workers' perceptions of health and safety on the farm in America's Heartland.
Liebman, Amy King; Juarez-Carrillo, Patricia Margarita; Reyes, Iris Anne Cruz; Keifer, Matthew Charles
2016-03-01
Dairy farming is dangerous. Yearly, farms grow fewer and larger by employing immigrant workers, who have limited industrial agriculture experience and safety and health training. We examined results of five focus groups with 37 Hispanic, immigrant dairy workers. Analysis followed a grounded theory approach and employed ATLAS.ti. Reported injury experience affirmed the hazardous nature of dairy. Some workers received appropriate worker compensation benefits, whereas others were instructed to deny work-relatedness. Some employers covered medical injury costs out-of-pocket, whereas others did not. Cows were a major injury source. Pressure to work and weather were noted as injury risk factors. Worker compensation was poorly understood, and immigration status and fear of deportation influenced injury and hazard reporting. Injury management practices range from benevolent to threatening. Workers compensation is poorly understood and undocumented status is an occupational hazard. We underscore the need for further research and immigration policy change. © 2015 Wiley Periodicals, Inc.
Direct observation of closed magnetic flux trapped in the high-latitude magnetosphere.
Fear, R C; Milan, S E; Maggiolo, R; Fazakerley, A N; Dandouras, I; Mende, S B
2014-12-19
The structure of Earth's magnetosphere is poorly understood when the interplanetary magnetic field is northward. Under this condition, uncharacteristically energetic plasma is observed in the magnetotail lobes, which is not expected in the textbook model of the magnetosphere. Using satellite observations, we show that these lobe plasma signatures occur on high-latitude magnetic field lines that have been closed by the fundamental plasma process of magnetic reconnection. Previously, it has been suggested that closed flux can become trapped in the lobe and that this plasma-trapping process could explain another poorly understood phenomenon: the presence of auroras at extremely high latitudes, called transpolar arcs. Observations of the aurora at the same time as the lobe plasma signatures reveal the presence of a transpolar arc. The excellent correspondence between the transpolar arc and the trapped closed flux at high altitudes provides very strong evidence of the trapping mechanism as the cause of transpolar arcs. Copyright © 2014, American Association for the Advancement of Science.
Sea-level-induced seismicity and submarine landslide occurrence
Brothers, Daniel S.; Luttrell, Karen M.; Chaytor, Jason D.
2013-01-01
The temporal coincidence between rapid late Pleistocene sea-level rise and large-scale slope failures is widely documented. Nevertheless, the physical mechanisms that link these phenomena are poorly understood, particularly along nonglaciated margins. Here we investigate the causal relationships between rapid sea-level rise, flexural stress loading, and increased seismicity rates along passive margins. We find that Coulomb failure stress across fault systems of passive continental margins may have increased more than 1 MPa during rapid late Pleistocene–early Holocene sea-level rise, an amount sufficient to trigger fault reactivation and rupture. These results suggest that sea-level–modulated seismicity may have contributed to a number of poorly understood but widely observed phenomena, including (1) increased frequency of large-scale submarine landslides during rapid, late Pleistocene sea-level rise; (2) emplacement of coarse-grained mass transport deposits on deep-sea fans during the early stages of marine transgression; and (3) the unroofing and release of methane gas sequestered in continental slope sediments.
Wang, Yong Xin; Mandal, Deendayal; Wang, Suizhau; Hughes, Dennis; Pollock, Raphael E; Lev, Dina; Kleinerman, Eugenie; Hayes-Jordan, Andrea
2009-01-01
Despite aggressive therapy, Ewing's sarcoma (ES) patients have a poor five-year overall survival of only 20-40%. Pulmonary metastasis is the most common form of demise in these patients. The pathogenesis of pulmonary metastasis is poorly understood and few orthotopic models exist that allow study of spontaneous pulmonary metastasis in ES. We have developed a novel orthotopic xenograft model in which spontaneous pulmonary metastases develop. While the underlying biology of ES is incompletely understood, in addition to the EWS-FLI-1 mutation, it is known that platelet-derived growth factor receptor beta (PDGFR-beta) is highly expressed in ES. Hypothesizing that PDGFR-beta expression is indicative of a specific role for this receptor protein in ES progression, the effect of PDGFR-beta inhibition on ES growth and metastasis was assessed in this novel orthotopic ES model. Silencing PDGFR-beta reduced spontaneous growth and metastasis in ES. Preclinical therapeutically relevant findings such as these may ultimately lead to new treatment initiatives in ES.
Cortical dendritic activity correlates with spindle-rich oscillations during sleep in rodents.
Seibt, Julie; Richard, Clément J; Sigl-Glöckner, Johanna; Takahashi, Naoya; Kaplan, David I; Doron, Guy; de Limoges, Denis; Bocklisch, Christina; Larkum, Matthew E
2017-09-25
How sleep influences brain plasticity is not known. In particular, why certain electroencephalographic (EEG) rhythms are linked to memory consolidation is poorly understood. Calcium activity in dendrites is known to be necessary for structural plasticity changes, but this has never been carefully examined during sleep. Here, we report that calcium activity in populations of neocortical dendrites is increased and synchronised during oscillations in the spindle range in naturally sleeping rodents. Remarkably, the same relationship is not found in cell bodies of the same neurons and throughout the cortical column. Spindles during sleep have been suggested to be important for brain development and plasticity. Our results provide evidence for a physiological link of spindles in the cortex specific to dendrites, the main site of synaptic plasticity.Different stages of sleep, marked by particular electroencephalographic (EEG) signatures, have been linked to memory consolidation, but underlying mechanisms are poorly understood. Here, the authors show that dendritic calcium synchronisation correlates with spindle-rich sleep phases.
Serpentine Soils Do Not Limit Mycorrhizal Fungal Diversity
Branco, Sara; Ree, Richard H.
2010-01-01
Background Physiologically stressful environments tend to host depauperate and specialized biological communities. Serpentine soils exemplify this phenomenon by imposing well-known constraints on plants; however, their effect on other organisms is still poorly understood. Methodology/Principal Findings We used a combination of field and molecular approaches to test the hypothesis that serpentine fungal communities are species-poor and specialized. We conducted surveys of ectomycorrhizal fungal diversity from adjacent serpentine and non-serpentine sites, described fungal communities using nrDNA Internal Transcribed Spacer (ITS) fragment and sequence analyses, and compared their phylogenetic community structure. Although we detected low fungal overlap across the two habitats, we found serpentine soils to support rich fungal communities that include representatives from all major fungal lineages. We failed to detect the phylogenetic signature of endemic clades that would result from specialization and adaptive radiation within this habitat. Conclusions/Significance Our results indicate that serpentine soils do not constitute an extreme environment for ectomycorrhizal fungi, and raise important questions about the role of symbioses in edaphic tolerance and the maintenance of biodiversity. PMID:20668696
CD271 Defines a Stem Cell-Like Population in Hypopharyngeal Cancer
Imai, Takayuki; Tamai, Keiichi; Oizumi, Sayuri; Oyama, Kyoko; Yamaguchi, Kazunori; Sato, Ikuro; Satoh, Kennichi; Matsuura, Kazuto; Saijo, Shigeru; Sugamura, Kazuo; Tanaka, Nobuyuki
2013-01-01
Cancer stem cells contribute to the malignant phenotypes of a variety of cancers, but markers to identify human hypopharyngeal cancer (HPC) stem cells remain poorly understood. Here, we report that the CD271+ population sorted from xenotransplanted HPCs possesses an enhanced tumor-initiating capability in immunodeficient mice. Tumors generated from the CD271+ cells contained both CD271+ and CD271− cells, indicating that the population could undergo differentiation. Immunohistological analyses of the tumors revealed that the CD271+ cells localized to a perivascular niche near CD34+ vasculature, to invasive fronts, and to the basal layer. In accordance with these characteristics, a stemness marker, Nanog, and matrix metalloproteinases (MMPs), which are implicated in cancer invasion, were significantly up-regulated in the CD271+ compared to the CD271− cell population. Furthermore, using primary HPC specimens, we demonstrated that high CD271 expression was correlated with a poor prognosis for patients. Taken together, our findings indicate that CD271 is a novel marker for HPC stem-like cells and for HPC prognosis. PMID:23626764
The Nutrient Density of Snacks
Hess, Julie; Rao, Goutham; Slavin, Joanne
2017-01-01
Background: Although Americans receive almost a quarter of their daily energy from snacks, snacking remains a poorly defined and understood eating occasion. However, there is little dietary guidance about choosing snacks. Families, clinicians, and researchers need a comprehensive approach to assessing their nutritional value. Objective: To quantify and compare the nutrient density of commonly consumed snacks by their overall nutrient profiles using the Nutrient-Rich Foods (NRF) Index 10.3. Methods: NRF Index scores were calculated for the top 3 selling products (based on 2014 market research data) in different snack categories. These NRF scores were averaged to provide an overall nutrient-density score for each category. Results: Based on NRF scores, yogurt (55.3), milk (52.5), and fruit (30.1) emerged as the most nutrient-dense snacks. Ice cream (−4.4), pies and cakes (−11.1), and carbonated soft drinks (−17.2) emerged as the most nutrient-poor snacks. Conclusions: The NRF Index is a useful tool for assessing the overall nutritional value of snacks based on nutrients to limit and nutrients to encourage. PMID:28491924
Hess, Julie; Rao, Goutham; Slavin, Joanne
2017-01-01
Background: Although Americans receive almost a quarter of their daily energy from snacks, snacking remains a poorly defined and understood eating occasion. However, there is little dietary guidance about choosing snacks. Families, clinicians, and researchers need a comprehensive approach to assessing their nutritional value. Objective: To quantify and compare the nutrient density of commonly consumed snacks by their overall nutrient profiles using the Nutrient-Rich Foods (NRF) Index 10.3. Methods: NRF Index scores were calculated for the top 3 selling products (based on 2014 market research data) in different snack categories. These NRF scores were averaged to provide an overall nutrient-density score for each category. Results: Based on NRF scores, yogurt (55.3), milk (52.5), and fruit (30.1) emerged as the most nutrient-dense snacks. Ice cream (-4.4), pies and cakes (-11.1), and carbonated soft drinks (-17.2) emerged as the most nutrient-poor snacks. Conclusions: The NRF Index is a useful tool for assessing the overall nutritional value of snacks based on nutrients to limit and nutrients to encourage.
A missed Fe-S cluster handoff causes a metabolic shakeup.
Berteau, Olivier
2018-05-25
The general framework of pathways by which iron-sulfur (Fe-S) clusters are assembled in cells is well-known, but the cellular consequences of disruptions to that framework are not fully understood. Crooks et al. report a novel cellular system that creates an acute Fe-S cluster deficiency, using mutants of ISCU, the main scaffold protein for Fe-S cluster assembly. Surprisingly, the resultant metabolic reprogramming leads to the accumulation of lipid droplets, a situation encountered in many poorly understood pathological conditions, highlighting unanticipated links between Fe-S assembly machinery and human disease. © 2018 Berteau.
The mystery of a supposed massive star exploding in a brightest cluster galaxy
NASA Astrophysics Data System (ADS)
Hosseinzadeh, Griffin
2017-08-01
Most of the diversity of core-collapse supernovae results from late-stage mass loss by their progenitor stars. Supernovae that interact with circumstellar material (CSM) are a particularly good probe of these last stages of stellar evolution. Type Ibn supernovae are a rare and poorly understood class of hydrogen-poor explosions that show signs of interaction with helium-rich CSM. The leading hypothesis is that they are explosions of very massive Wolf-Rayet stars in which the supernova ejecta excites material previously lost by stellar winds. These massive stars have very short lifetimes, and therefore should only found in actively star-forming galaxies. However, PS1-12sk is a Type Ibn supernova found on the outskirts of a giant elliptical galaxy. As this is extraordinary unlikely, we propose to obtain deep UV images of the host environment of PS1-12sk in order to map nearby star formation and/or find a potential unseen star-forming host. If star formation is detected, its amount and location will provide deep insights into the progenitor picture for the poorly-understood Type Ibn class. If star formation is still not detected, these observations would challenge the well-accepted hypothesis that these are core-collapse supernovae at all.
NASA Astrophysics Data System (ADS)
O'Connor, Thomas; Robbins, Mark
Glassy polymers are a ubiquitous part of modern life, but much about their mechanical properties remains poorly understood. Since chains in glassy states are hindered from exploring their conformational entropy, they can't be understood with common entropic network models. Additionally, glassy states are highly sensitive to material history and nonequilibrium distributions of chain alignment and entanglement can be produced during material processing. Understanding how these far-from equilibrium states impact mechanical properties is analytically challenging but essential to optimizing processing methods. We use molecular dynamics simulations to study the yield and strain hardening of glassy polymers as separate functions of the degree of molecular alignment and inter-chain entanglement. We vary chain alignment and entanglement with three different preparation protocols that mimic common processing conditions in and out of solution. We compare our results to common mechanical models of amorphous polymers and assess their applicability to different experimental processing conditions. This research was performed within the Center for Materials in Extreme Dynamic Environments (CMEDE) under the Hopkins Extreme Materials Institute at Johns Hopkins University. Financial support was provided by Grant W911NF-12-2-0022.
Exposure to mixtures is frequent, but biologic pathways such as metabolic inhibition, are poorly understood. CHCl3 and TCE are model volatiles frequently co-occurring; combined exposure results in less than additive hepatotoxicity. Here, we explore the underlying metabolic inte...
DOT National Transportation Integrated Search
1998-03-01
The contribution of a cement-stabilized base course to the strength of the rigid pavement structure is poorly understood. The objective of this research was to obtain data on the response of the rigid pavement slab-joint-foundation system by conducti...
Childhood asthma is a multifactorial disease with a disturbingly high incidence in urbanized areas. The pathogenesis of asthma is poorly understood due to the complex relationship between genetic susceptibility and modulating environmental factors. The Mechanistic Indicators of C...
NITROGEN OUTPUTS FROM FECAL AND URINE DEPOSITION OF SMALL MAMMALS: IMPLICATIONS FOR NITROGEN CYCLING
The contribution of small mammals to nitrogen cycling is poorly understood, but it could have reverberations back to the producer community by maintaining or perhaps magnifying nitrogen availability. Our objective was to model nitrogen outputs (deposition of feces and urine) of ...
Accumulation of the antibiotic phenazine-1-carboxylic acid in the rhizosphere of dryland cereals
USDA-ARS?s Scientific Manuscript database
Natural antibiotics are thought to function in microbial defense, fitness, competitiveness, biocontrol, communication and gene regulation. However, the frequency and amount of antibiotics produced in nature are poorly understood. In this study, we assessed the geographic distribution of indigenous p...
Genomic medicine and ethnic differences in cardiovascular disease risk
USDA-ARS?s Scientific Manuscript database
The origins of health disparities are a poorly understood public health problem. The effects of culture, environmental hazards, and social marginalization differ between ethnicities and have strong effects on health differences. The role of the genome in health is well established and we present a s...
BACKGROUND: Influenza peaks during the wintertime in temperate regions and during the annual rainy season in tropical regions – however reasons for the observed differences in disease ecology are poorly understood. We hypothesize that episodes of extreme precipitation also result...
USDA-ARS?s Scientific Manuscript database
During polarized growth of pollen tubes, endomembrane trafficking and actin polymerization are two critical processes that establish membrane/wall homeostasis and maintain growth polarity. Fine-tuned interactions between these two processes are therefore necessary but poorly understood. To better un...
DOT National Transportation Integrated Search
2016-02-01
Rural intersections account for 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly : understood safety problem. Transportation agencies have traditionally implemented countermeasures to address rural inte...
Flavonoids, alkali earth and rare earth elements affect germination of pecan pollen
USDA-ARS?s Scientific Manuscript database
The factors regulating pecan [Carya illinoinensis (Wangenh.) K. Koch] pollen grain germination on receptive stigmatic flower surfaces in vivo or in vitro in pollen viability assays are poorly understood. While there are many potential regulating factors, there is evidence for involvement of flavonol...
Neural Correlates of Socioeconomic Status in the Developing Human Brain
ERIC Educational Resources Information Center
Noble, Kimberly G.; Houston, Suzanne M.; Kan, Eric; Sowell, Elizabeth R.
2012-01-01
Socioeconomic disparities in childhood are associated with remarkable differences in cognitive and socio-emotional development during a time when dramatic changes are occurring in the brain. Yet, the neurobiological pathways through which socioeconomic status (SES) shapes development remain poorly understood. Behavioral evidence suggests that…
USDA-ARS?s Scientific Manuscript database
Liver toxicity is frequently seen in relation to allogeneic hematopoietic stem cell transplantation (HSCT), but pathogenesis and the risk factors are poorly understood. The purpose of this study was to investigate associations between liver toxicity, gastrointestinal toxicity, and levels of immune-r...
NITROGEN OUTPUTS OF SMALL MAMMALS FROM FECAL AND URINE DEPOSITION: IMPLICATIONS FOR NITROGEN CYCLING
The contribution of small mammals in nitrogen cycling is poorly understood and could have reverberations back to the producer community by maintaining or even magnifying increased nitrogen availability. Our objective was to model nitrogen outputs (deposition of feces and urine) ...
Feeding behavior and injury caused by Lygus hesperus
USDA-ARS?s Scientific Manuscript database
Despite the importance of Lygus hesperus as a crop pest in the western United States, key aspects of its feeding behavior and consequent injury to cotton are poorly understood. Previous studies of Lygus stage-dependent injury to cotton produced conflicting results. We sought to clarify these relat...
Structural Equations and Causal Explanations: Some Challenges for Causal SEM
ERIC Educational Resources Information Center
Markus, Keith A.
2010-01-01
One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete…
USDA-ARS?s Scientific Manuscript database
Contamination of aquatic habitats with anthropogenic nutrients has been associated with an increase in mosquito larval populations but the underlying mechanisms remain poorly understood. We examined the individual and combined effects of two synthetic fertilizers (ammonium sulfate and potassium chlo...
Verbal Understanding and Pavlovian Processes
ERIC Educational Resources Information Center
Tonneau, François
2004-01-01
The behavioral processes through which people react appropriately to verbal descriptions remain poorly understood. I argue here that these processes are Pavlovian. Common objections to a Pavlovian account of symbolic behavior evidence a lack of familiarity with the relevant data or misunderstandings of operant theory. Although much remains to be…
Redefining the Longitude/Latitude Experience with a Scaffolded Geocache
ERIC Educational Resources Information Center
Hammond, Thomas; Bozdin, Alec M.; Stanlick, Sarah E.
2014-01-01
Latitude and longitude are foundational concepts for geography education, yet they are typically poorly understood by students and receive indifferent attention from instructors and publishers' materials. Social studies teachers can take advantage of increasingly ubiquitous geolocating devices such as Global Positions Systems (GPS) to provide…
Wheat streak mosaic virus coat protein is a host-specific long-distance transport determinant in oat
USDA-ARS?s Scientific Manuscript database
Viral determinants involved in systemic infection of hosts by monocot-infecting plant viruses are poorly understood. Wheat streak mosaic virus (WSMV, genus Tritimovirus, family Potyviridae) exclusively infects monocotyledonous crops such as wheat, oat, barley, maize, triticale, and rye. Previously, ...
Genotype-specific responses of apple roots to pathogenic infection by Pythium ultimum
USDA-ARS?s Scientific Manuscript database
Resistance mechanisms employed to defend against soilborne necrotrophic pathogens are poorly understood, particularly with respect to perennial tree fruit crops such as apple. Pythium ultimum is a component of the pathogen complex that incites apple replant disease (ARD). Different levels of tolera...
The Structure of Integral Dimensions: Contrasting Topological and Cartesian Representations
ERIC Educational Resources Information Center
Jones, Matt; Goldstone, Robert L.
2013-01-01
Diverse evidence shows that perceptually integral dimensions, such as those composing color, are represented holistically. However, the nature of these holistic representations is poorly understood. Extant theories, such as those founded on multidimensional scaling or general recognition theory, model integral stimulus spaces using a Cartesian…
Speleothems as Examples of Chemical Equilibrium Processes.
ERIC Educational Resources Information Center
Wilson, James R.
1984-01-01
The chemical formation of speleothems such as stalactites and stalagmites is poorly understood by introductory geology instructors and misrepresented in most textbooks. Although evaporation may be a controlling factor in some caves, it is necessary to consider chemical precipitation as more important in controlling the diagenesis of calcium…
Aboveground and belowground net primary production
Hal O. Liechty; Mark H. Eisenbies
2000-01-01
The relationship among net primary productivity (NPP), hydroperiod, and fertility in forested wetlands is poorly understood (Burke and others 1999), particularly with respect to belowground NPP (Megonigal and others 1997). Although some researchers have studied aboveground and belowground primary production in depressional, forested wetland systems, e.g., Day and...
Remote Sensing and Underwater Glider Observations of a Springtime Plume in Western Lake Superior
Plumes are commonly observed in satellite imagery of western Lake Superior following storm events, and represent a significant cross-shelf pathway for sediment and other constituents. However, their subsurface extent is poorly understood. This study reports results from plume ob...
Effects of Rhododendron maximum L. on Acer rubrum L. Seedling Establishment
Barton D. Clinton; James M. Vose
1996-01-01
Rhododendron maximum L. restricts regeneration of overstory species; however, the mechanisms are poorly understood. Three treatments were used to examine the effects of R. maximum germination success and survival of Acer rubrum L. under a closed overstory canopy: (1) R. maximum understory, (2)...
The effects of anthropogenic contaminants on Gulf of Mexico plant communities are poorly understood despite the threatened condition of a number of seagrass communities and wetland habitats. In this study, we focused particular attention on the concern that elevated nutrient
l...
The Psychophysiological Mechanisms of Alexithymia in Autism Spectrum Disorder
ERIC Educational Resources Information Center
Gaigg, Sebastian B.; Cornell, Anna S. F.; Bird, Geoffrey
2018-01-01
Accumulating evidence indicates that co-occurring alexithymia underlies several facets of the social-emotional difficulties common in individuals with autism spectrum disorder. The mechanisms involved, however, remain poorly understood because measuring alexithymia relies heavily on self-report. To address this issue, carefully matched groups of…
Sugary beverage intake and preclinical Alzheimer's disease in the community
USDA-ARS?s Scientific Manuscript database
IMPORTANCE: Sugary beverages are a key component of the Western diet, yet the long-term effects of these beverages on the brain are poorly understood. OBJECTIVE: To determine whether habitual sugary beverage consumption is associated with markers of preclinical Alzheimers disease (AD) and/or vascu...
Spread and development of Phytophthora ramorum in a California christmas tree farm
Gary A. Chastagner; Kathy Riley; Norm Dart
2008-01-01
The risk of conifers being infected by Phytophthora ramorum under natural conditions is poorly understood. In California, infected conifers commonly occur as understory plants beneath or adjacent to heavily infected plants like California bay laurel (Umbellularia californica). During wet periods, P. ramorum is...
Satellite observation of particulate organic carbon dynamics on the Louisiana continental shelf
Particulate organic carbon (POC) plays an important role in coastal carbon cycling and the formation of hypoxia. Yet, coastal POC dynamics are often poorly understood due to a lack of long-term POC observations and the complexity of coastal hydrodynamic and biogeochemical process...
HYDRAULIC REDISTRIBUTION IN A DOUGLAS-FIR FOREST: LESSONS FROM SYSTEM MANIPULATIONS
Hydraulic redistribution (HR) has been shown to slow drying of surface soils during drought in Pacific Northwest forests, but the controls governing this process and its importance to shallow-rooted species are poorly understood. Our objective in this study was to manipulate the...
Perfluoro compounds are ubiquitous contaminants in human blood. The pathways which result in near universal exposure to humans in modern societies are not clearly understood. Sources to environmental compartments and transport between compartments are only poorly studies, and thi...
Glucose supplementation has minimal effects on blood neutrophil functionand gene expression in vitro
USDA-ARS?s Scientific Manuscript database
During early lactation, glucose availability is low and the effect of glucose supply on bovine polymorphonuclear leukocyte (PMNL) function is poorly understood. The objective of this study was to determine the effect of glucose supplementation on the function and transcriptomic inflammatory respons...
The water balance components of undisturbed tropical woodlands in the Brazilian cerrado
USDA-ARS?s Scientific Manuscript database
Deforestation of the Brazilian cerrado region has caused major changes in hydrological processes. These changes in water balance components are still poorly understood but are important for making land management decisions in this region. To better understand pre-deforestation conditions, we determi...
Soil type and species diversity influence selection on physiology in Panicum virgatum
USDA-ARS?s Scientific Manuscript database
Species diversity influences the productivity and stability of plant communities, but its effect on the evolution of species within those communities is poorly understood. In this study, we tested whether species diversity and soil type influence selection on physiology in switchgrass (Panicum virga...
Mechanisms of increased lifespan in hypoxia in the alfalfa leafcutting bee, Megachile rotundata
USDA-ARS?s Scientific Manuscript database
Genetic variation accounts for a small amount of variation in lifespan, while environmental stressors are strong predictors. Hypoxia is an environmental stress that increases longevity in some contexts, but the mechanisms remain poorly understood. In the bee Megachile rotundata, lifespan doubles upo...
δ 13C of free and macromolecular aromatic structures in the murchison meteorite
NASA Astrophysics Data System (ADS)
Sephton, M. A.; Pillinger, C. T.; Gilmour, I.
1998-05-01
Analyses of the organic compounds in the Murchison meteorite have led to a greater understanding of the nature of extraterrestrial organic materials. However, the relationship between low and high molecular weight material remains poorly understood. To investigate this relationship, untreated Murchison was subjected to supercritical fluid extraction (SFE) to obtain the free organic components in the meteorite. Toluene and other volatile aromatic hydrocarbons dominated the extract, and the carbon isotopic composition of these molecules was determined by gas chromatography-isotope ratio-mass spectrometry (GCIRMS). δ 13C values of the aromatic hydrocarbons ranged from -28.8 to -5.8‰. These compounds displayed a 13C-enrichment with increasing carbon number suggesting an origin by cracking. The high molecular weight organic material in the meteorite was isolated and subjected to hydrous pyrolysis. This procedure produced a number of aromatic products, the majority of which were volatile aromatic hydrocarbons, particularly toluene. SFE was used to extract and successfully retain them. This enabled the first carbon isotopic analysis of this poorly understood material to be performed at the molecular level by GCIRMS. δ 13C values for aromatic pyrolysis products occupied a range from -24.6 to -5.6‰. The trend of 13C-enrichment with increasing carbon number, observed in the free compounds, was also evident in the macromolecular fragments. Furthermore, the organic fragments of the macromolecular material were consistently 13C-enriched when compared to structurally identical free molecules. This suggested that the free aromatic hydrocarbons in Murchison were produced by the preterrestrial degradation of the organic macromolecular material. This natural degradation event was extended by the hydrous pyrolysis experiment.
Right ventricular involution: What can we learn from nature's model of compensated hypertrophy?
Bowen, Megan E; Liu, Xiaoqing; Sundwall, Peter M; Drakos, Stavros G; Li, Dean Y; Selzman, Craig H; McKellar, Stephen H
2018-05-01
Right ventricular (RV) failure (RVF) is a vexing problem facing patients with various disease processes and carries a high mortality. RVF is a poorly understood phenomenon with limited treatment options. In mammalian fetal circulation, the right ventricle is the systemic ventricle. In neonates, however, the left ventricle assumes that role and gradually thickens compared with the right ventricle. This process, known as right ventricular involution (RVI), is poorly understood. We sought to define the time course and identify mechanisms involved in RVI. Wild-type mice were bred and sacrificed on day of life (DOL) 1, 4, 8, 16, and 30 to evaluate left ventricular (LV) and RV wall thickness and apoptosis. A terminal deoxynucleotidyl transferase nick-end labeling assay and RNA sequencing were performed to measure changes during RVI. Morphometric analysis demonstrated the changes in RV and LV wall thickness occurring between DOL 1 and DOL 16 (RV:LV, 0.53:0.44; P = .03). In addition, apoptosis was most active early, with the highest percentage of apoptotic cells on DOL 1 (1.0%) and a significant decrease by DOL 30 (0.23%) (P = .02). Similarly, expression of the proapoptotic genes BCL2l11 and Pawr were increased at DOL 1, and the antiapoptotic genes Nol3 and Naip2 were significantly increased at DOL 30. RVI is a misnomer, but significant changes occur early (by DOL 16) in neonatal mouse hearts. Apoptosis plays a role in RVI, but whether manipulation of apoptotic pathways can prevent or reverse RVI is unknown and warrants further investigation. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
Evidence synthesis and its role in evidence-based health care.
Pearson, Alan
2014-12-01
The central role of evidence synthesis (or the systematic review of evidence) in evidence-based health care is often poorly understood. There are numerous examples in the literature of poorly conceived and/or executed systematic reviews and of a lack of awareness of the international standards developed by the international leaders in systematic reviews. The Cochrane Collaboration has played a critical global role in developing and refining systematic review methods in relation to evidence of effects and of diagnostic accuracy. Copyright © 2014 Elsevier Inc. All rights reserved.
USDA-ARS?s Scientific Manuscript database
In lower vertebrates, the contribution of the spleen to anti-bacterial immunity is poorly understood. Researchers have previously reported a phenotypic and genetic correlation between resistance to Flavobacterium psychrophilum, the causative agent of bacterial cold water disease (BCWD) and spleen so...
A sprinkling experiment to quantify celerity-velocity differences at the hillslope scale
The difference between celerity and velocity of hillslope water flow is poorly understood. We assessed these differences by combining a 24-day hillslope sprinkling experiment with a spatially explicit hydrologic model analysis. We focused our work at Watershed 10 at the H.J. And...
Impaired Associative Taste Learning and Abnormal Brain Activation in Kinase-Defective eEF2K Mice
ERIC Educational Resources Information Center
Gildish, Iness; Manor, David; David, Orit; Sharma, Vijendra; Williams, David; Agarwala, Usha; Wang, Xuemin; Kenney, Justin W.; Proud, Chris G.; Rosenblum, Kobi
2012-01-01
Memory consolidation is defined temporally based on pharmacological interventions such as inhibitors of mRNA translation (molecular consolidation) or post-acquisition deactivation of specific brain regions (systems level consolidation). However, the relationship between molecular and systems consolidation are poorly understood. Molecular…
METABOLISM OF PBDES IN FATHEAD MINNOWS (PIMEPHALES PROMELAS) AND EFFECTS ON THYROID REGULATION
PBDE effects on fish and other wildlife continue to be poorly understood, and this research will contribute to filling this data gap. It will increase our understanding of PBDE metabolic pathways and mechanisms of thyroid dysfunction in fish exposed to this important class of ...
ERIC Educational Resources Information Center
Sashittal, Hemant C.; Jassawalla, Avan R.; Markulis, Peter
2012-01-01
Apathy and social disconnectedness among undergraduate business students remain poorly understood and under-researched--despite evidence that they produce an adverse impact on learning-related outcomes. Qualitative research was initially conducted among a sample of undergraduate business students to identify the antecedents and learning-related…
Heredia-Langner, Alejandro; Cort, John; Bailey, Vanessa
2018-01-16
The Fishing for Features Signature Discovery project developed a framework for discovering signature features in challenging environments involving large and complex data sets or where phenomena may be poorly characterized or understood. Researchers at PNNL have applied the framework to the optimization of biofuels blending and to discover signatures of climate change on microbial soil communities.
This project examined a common, but poorly understood, problem associated with land development, namely the modifications made to soil structure and the associated reduced rainfall infiltration and increased runoff. The project was divided into two separate major tasks: 1) to tes...
Engineering Education as a Complex System
ERIC Educational Resources Information Center
Gattie, David K.; Kellam, Nadia N.; Schramski, John R.; Walther, Joachim
2011-01-01
This paper presents a theoretical basis for cultivating engineering education as a complex system that will prepare students to think critically and make decisions with regard to poorly understood, ill-structured issues. Integral to this theoretical basis is a solution space construct developed and presented as a benchmark for evaluating…
Can Near-Peer Teaching Improve Academic Performance?
ERIC Educational Resources Information Center
Williams, Brett; Fowler, James
2014-01-01
Near peer teaching is becoming increasingly popular within healthcare education. The experiences and effects of near-peer teaching upon the near-peer teachers' academic performance are poorly understood. In order to address this, the objective of this study was to examine whether a near-peer teaching program improved the overall clinical unit…
Stages and Spatial Scales of Recruitment Limitation in Southern Appalachain Forests
James S. Clark; Eric Macklin; Leslie Wood
1998-01-01
Recruitment limitation of tree population dynamics is poorly understood, because fecundity and dispersal are difficult to characterize in closed stands. We present an approach that estimates seed production and dispersal under closed canopies and four limitations on recruitment: tree density and location, fecundity, seed dispersal, and establishment. Consistent...
Genetic structure and domestication of carrot (Daucus carota subsp. sativus L.) (Apiaceae)
USDA-ARS?s Scientific Manuscript database
Analyses of genetic structure and phylogenetic relationships illuminate the origin and domestication of modern crops. Despite being an important world-wide vegetable, the genetic structure and domestication of carrot (Daucus carota L.) is poorly understood. We provide the first such study using a la...
Emotional climate and feeding styles: observational analysis of dinner in low-income families
USDA-ARS?s Scientific Manuscript database
Indulgent feeding styles have been associated with a higher risk for childhood overweight. The processes through which feeding styles impact child weight are poorly understood. The aim of this study was to observe differences in the emotional climate created by parents (affect, tone of voice, gest...
USDA-ARS?s Scientific Manuscript database
The Asian soybean rust fungus, Phakopsora pachyrhizi, is an obligate pathogen capable of causing explosive disease epidemics that drastically reduce the yield of soybean (Glycine max). Currently, the molecular mechanisms by which P. pachyrhizi and other rust fungi cause disease are poorly understood...
Developing Research Relationships toward a Learning Partnership
ERIC Educational Resources Information Center
Kaasila, Raimo; Lutovac, Sonja
2015-01-01
Research relationships are often poorly understood. Why are some collaborations between research partners more productive than others? This question was a starting point of this paper. By describing their own experiences over a period of three years, the authors evaluated research relationships through collaborative self-study. At the beginning,…
Reciprocal Peer Coaching: A Critical Contributor to Implementing Individual Leadership Plans
ERIC Educational Resources Information Center
Goldman, Ellen; Wesner, Marilyn; Karnchanomai, Ornpawee
2013-01-01
Billions of dollars are spent annually on programs to develop organizational leaders, yet the effectiveness of these programs is poorly understood. Scholars advise that value is enhanced by the development of individual leadership plans at program completion, followed by implementation experience with subsequent coaching and reflection. The…
BEL1-LIKE HOMEODOMAIN 11 regulated chloroplast development and chlorophyll synthesis in tomato fruit
USDA-ARS?s Scientific Manuscript database
Chloroplast development and chlorophyll content and metabolism in unripe tomato contribute to the growth and development of the fruit, and also the ripe fruit quality, but the mechanism is poorly understood. In this work, seven homeobox-containing transcription factors (TFs) with specific ripening-a...
Geographic variation in mycangial communities of Xyleborus glabratus
USDA-ARS?s Scientific Manuscript database
Abstract Factors that influence fungal communities in ambrosia beetle mycangia are poorly understood. The beetle that is responsible for spreading laurel wilt in the SE USA, Xyleborus glabratus, was examined at three sites along a 500 km N-S transect in Florida, each populated by host trees in the ...
Effects of Post-Encoding Stress on Performance in the DRM False Memory Paradigm
ERIC Educational Resources Information Center
Pardilla-Delgado, Enmanuelle; Alger, Sara E.; Cunningham, Tony J.; Kinealy, Brian; Payne, Jessica D.
2016-01-01
Numerous studies have investigated how stress impacts veridical memory, but how stress influences false memory formation remains poorly understood. In order to target memory consolidation specifically, a psychosocial stress (TSST) or control manipulation was administered following encoding of 15 neutral, semantically related word lists (DRM false…
ROOT GROWTH AND TURNOVER IN DIFFERENT AGED PONDEROSA PINE STANDS IN OREGON, USA
The impacts of pollution and climate change on soil carbon dynamics are poorly understood, in part due to a lack of information regarding root production and turnover in natural ecosystems. In order to examine how root dynamics change with stand age in ponderosa pine forests (...
Critical role for CCAAT/Enhancer-binding protein beta in immune complex-induced acute lung injury
USDA-ARS?s Scientific Manuscript database
Although inflammation plays a central role in the pathogenesis of acute lung injury (ALI), the molecular mechanisms underlying inflammatory responses in ALI are poorly understood, and therapeutic options remain limited. The CCAAT/enhancer-binding protein (C/EBP) gamma and -gamma have been implicated...
Starvation Promotes Odor/Feeding-Time Associations in Flies
ERIC Educational Resources Information Center
Chouhan, Nitin Singh; Wolf, Reinard; Heisenberg, Martin
2017-01-01
Starvation causes a motivational state that facilitates diverse behaviors such as feeding, walking, and search. Starved "Drosophila" can form odor/feeding-time associations but the role of starvation in encoding of "time" is poorly understood. Here we show that the extent of starvation is correlated with the fly's ability to…
Cobalt Distribution and Speciation: Effect of Aging, Intermittent Submergence, In situ Rice Roots
The speciation and distribution of cobalt (Co) in soils is poorly understood. This study was conducted using X-ray absorption spectroscopy (XAS) techniques to examine the influence of soluble Co(II) aging, submergence-dried cycling, and the presence of in vivo rice roots on the...
What makes Great Basin sagebrush ecosystems invasible by Bromus tectorum?
Jeanne C. Chambers; Bruce A. Roundy; Robert R. Blank; Susan E. Meyer; A. Whittaker
2007-01-01
Ecosystem susceptibility to invasion by nonnative species is poorly understood, but evidence is increasing that spatial and temporal variability in resources has large-scale effects. We conducted a study in Artemisia tridentata ecosystems at two Great Basin locations examining differences in resource availability and invasibility of Bromus...
RATIONALE: Exposure to ambient particulate matter (PM) and ozone has been associated with cardiovascular disease (CVD). However, the mechanisms linking PM and ozone exposure to CVD remain poorly understood .OBJECTIVE: This study explored associations between short-term exposures ...
Accessing and Selecting Word Meaning in Autism Spectrum Disorder
ERIC Educational Resources Information Center
Henderson, L. M.; Clarke, P. J.; Snowling, M. J.
2011-01-01
Background: Comprehension difficulties are commonly reported in autism spectrum disorder (ASD) but the causes of these difficulties are poorly understood. This study investigates how children with ASD access and select meanings of ambiguous words to test four hypotheses regarding the nature of their comprehension difficulties: semantic deficit,…
USDA-ARS?s Scientific Manuscript database
Next generation fungal amplicon sequencing is being used with increasing frequency to study fungal diversity in various ecosystems; however, the influence of sample preparation on the characterization of fungal community is poorly understood. We investigated the effects of four procedural modificati...
Large-bodied invertebrates (bivalves, polychaetes, burrowing shrimps) are common to infaunal communities of NE Pacific estuaries, but their contribution to estuarine community structure, function and ecosystem services is poorly understood because they are difficult to sample and...
Coping Mediates the Association between Gender and Depressive Symptomatology in Adolescence
ERIC Educational Resources Information Center
Malooly, Ashley M.; Flannery, Kaitlin M.; Ohannessian, Christine McCauley
2017-01-01
Previous studies have found evidence for gender and racial/ethnic differences in depressive symptoms in adolescence; however, the mechanisms driving this relationship are poorly understood. The goal of this study was to examine the role of individual differences in dispositional coping in the relationships between gender and depressive…
USDA-ARS?s Scientific Manuscript database
The optimal defense theory (ODT) predicts that plants allocate defense compounds to their tissues depending on its value and the likelihood of herbivore attack. Whereas ODT has been confirmed for static damage levels it remains poorly understood if ODT holds true for defense organization of inducibl...
Drought and leaf herbivory influence floral volatiles and pollinator attraction
Laura A. Burkle; Justin B. Runyon
2016-01-01
The effects of climate change on species interactions are poorly understood. Investigating the mechanisms by which species interactions may shift under altered environmental conditions will help form a more predictive understanding of such shifts. In particular, components of climate change have the potential to strongly influence floral volatile organic...
Ozone exposure decreases belowground carbon allocation and root growth of plants;however,the extent to which these effects persist and the cumulative impact of ozone stress on plant growth are poorly understood.To evaluate the potential for plant compensation,we followed the prog...
Rationale: Exposure to particulate matter is a risk factor for cardiopulmonary disease but the related molecular mechanisms are poorly understood. Previously we studied cardiovascular responses in healthy WKY rats following inhalation exposure to ultrafine carbon particles (UfCPs...
Relationship of neuropeptide FF receptors with pubertal maturation of gilts
USDA-ARS?s Scientific Manuscript database
Mechanisms governing the timing of puberty in pigs are poorly understood. A genome-wide association study for age at first estrus in pigs identified candidate genes including NPFFR2, which is a putative receptor for RFamide-related peptides (RFRP). RFRP has been shown to negatively regulate secret...
Development of Sensitivity to Audiovisual Temporal Asynchrony during Midchildhood
ERIC Educational Resources Information Center
Kaganovich, Natalya
2016-01-01
Temporal proximity is one of the key factors determining whether events in different modalities are integrated into a unified percept. Sensitivity to audiovisual temporal asynchrony has been studied in adults in great detail. However, how such sensitivity matures during childhood is poorly understood. We examined perception of audiovisual temporal…
Understanding Authority in Classrooms: A Review of Theory, Ideology, and Research
ERIC Educational Resources Information Center
Pace, Judith L.; Hemmings, Annette
2007-01-01
Authority is a fundamental, problematic, and poorly understood component of classroom life. A better understanding of classroom authority can be achieved by reviewing writings on social theory, educational ideology, and qualitative research in schools. Social theories provide important analytical tools for examining the constitutive elements of…
Impacts of feral horse use on riparian vegetation within the sagebrush steppe
USDA-ARS?s Scientific Manuscript database
Feral horses inhabit rangeland ecosystems around the world, but their impacts on riparian ecosystems are poorly understood. We characterized impacts of a free-ranging horse population on the structure and composition of riparian plant communities in the sagebrush steppe ecosystem in the western US....
The industrial solvent perchloroethylene (PERC) is listed as a hazardous air pollutant in the 1990 Ammendments to Clean Air Act and is a known neurotoxicant. However, the mechanisms by which PERC alters nervous system function are poorly understood. In recent years, it has been d...
USDA-ARS?s Scientific Manuscript database
The fungus Slafractonia leguminicola, the causal agent of blackpatch disease of legumes produces two mycotoxins slaframine and swainsonine, causing slobbers’ symptoms and locoism of grazing animals, respectively. The genetics of this important fungus is poorly understood. This work aimed to develop ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heredia-Langner, Alejandro; Cort, John; Bailey, Vanessa
2016-07-21
The Fishing for Features Signature Discovery project developed a framework for discovering signature features in challenging environments involving large and complex data sets or where phenomena may be poorly characterized or understood. Researchers at PNNL have applied the framework to the optimization of biofuels blending and to discover signatures of climate change on microbial soil communities.
Teaching the Role of Mitochondrial Transport in Energy Metabolism
ERIC Educational Resources Information Center
Passarella, Salvatore; Atlante, Anna
2007-01-01
Studies from our laboratories over recent years have uncovered the existence, and established the properties of a variety of mitochondrial transporters. The properties of these transporters throw light on a variety of biochemical phenomena that were previously poorly understood. In particular the role of mitochondrial transport in energy…
Tiered Pricing: Implications for Library Collections
ERIC Educational Resources Information Center
Hahn, Karla
2005-01-01
In recent years an increasing number of publishers have adopted tiered pricing of journals. The design and implications of tiered-pricing models, however, are poorly understood. Tiered pricing can be modeled using several variables. A survey of current tiered-pricing models documents the range of key variables used. A sensitivity analysis…
Feeding Patterns and Emotional Care in Breastfed Infants
ERIC Educational Resources Information Center
Smith, Julie P.; Ellwood, Mark
2011-01-01
A number of studies have suggested breastfed infants have improved bonding and attachment or cognitive development outcomes. However, mechanisms by which these differences might develop are poorly understood. We used maternal time use data to examine whether exclusively breastfeeding mothers spend more time in close interactive behaviors with…
The influence of aging on susceptibility to environmental contaminants is poorly understood. The objectives of this study were to test whether oxidative stress (OS) is a potential toxicity pathway following toluene exposure and to determine if these effects are age-dependent. We ...
Altered belowground carbon cycling following land use change to perennial bioenergy crops
USDA-ARS?s Scientific Manuscript database
Belowground carbon (C) dynamics of terrestrial ecosystems play an important role in the global C cycle and thereby in climate regulation, yet remain poorly understood. Globally, land use change is a major driver of changes in belowground C storage; in general, land clearing and tillage for agricult...
Measuring and Inducing Brain Plasticity in Chronic Aphasia
ERIC Educational Resources Information Center
Fridriksson, Julius
2011-01-01
Brain plasticity associated with anomia recovery in aphasia is poorly understood. Here, I review four recent studies from my lab that focused on brain modulation associated with long-term anomia outcome, its behavioral treatment, and the use of transcranial brain stimulation to enhance anomia treatment success in individuals with chronic aphasia…
USDA-ARS?s Scientific Manuscript database
The adaptation of insect populations to insecticidal control is a continual threat human health and sustainable agriculture practices, but many complex genomic mechanisms involved remain poorly understood. A systems approach was applied to investigate the interconnections between structural and func...
USDA-ARS?s Scientific Manuscript database
Ethylene regulates multiple developmental processes during a plant life cycle, but the effect of ethylene on the upregulation of senescence-, stress-, and post-harvest-related genes in forage grasses is poorly understood. In this work, we used quantitative PCR to determine whether ethylene applicat...
USDA-ARS?s Scientific Manuscript database
Deficit irrigation reduces seasonal carbohydrate supply and decreases starch concentrations in vegetative tissues. The specific role of starch metabolism in conferring tolerance to cold is still poorly understood. A decrease in cold tolerance after sequential years of deficit irrigation would limit ...
Prevalence of obesity: A public health problem poorly understood
USDA-ARS?s Scientific Manuscript database
This review article discusses the Dietary Guidelines for Americans in support of a total diet approach to achieving diet and health goals, especially as they relate to the obesity epidemic. However, some scientists and organizations have identified one food, food group, or nutrient as the cause of t...
A Qualitative Approach to Understanding Audience's Perceptions of Creativity in Online Advertising
ERIC Educational Resources Information Center
McStay, Andrew
2010-01-01
In this paper I seek to inquire upon audience's perceptions of creativity in online advertising--a heretofore poorly understood area. This paper initially outlines current academic understanding of creativity in online advertising, mainly derived from quantitative assessments. It then advances a qualitative methodology including diary-interviews…
Secondary organic aerosols (SOA), known to form in the atmosphere from oxidation of volatile organic compounds (VOCs) emitted by anthropogenic and biogenic sources, are a poorly understood but substantial component of atmospheric particles. In this study, we examined the chemic...
Structuring Program Analysis for Educational Research.
ERIC Educational Resources Information Center
Levine, Donald M.
Education is too complex, multidimensional, and poorly understood to lend itself to a single cost/effectiveness criterion. Rather, analysts in the educational field seek to rank alternatives by their effectiveness, report separately on the cost implications, and leave the tradeoffs to the decisionmaker's judgment. In this context, a program is any…
Inhibition in Dot Comparison Tasks
ERIC Educational Resources Information Center
Clayton, Sarah; Gilmore, Camilla
2015-01-01
Dot comparison tasks are commonly used to index an individual's Approximate Number System (ANS) acuity, but the cognitive processes involved in completing these tasks are poorly understood. Here, we investigated how factors including numerosity ratio, set size and visual cues influence task performance. Forty-four children aged 7-9 years completed…
Social Attribution Processes and Comorbid Psychiatric Symptoms in Children with Asperger Syndrome
ERIC Educational Resources Information Center
Meyer, Jessica A.; Mundy, Peter C.; Van Hecke, Amy Vaughan; Durocher, Jennifer Stella
2006-01-01
The factors that place children with Asperger syndrome at risk for comorbid psychiatric symptoms, such as anxiety and depression, remain poorly understood. We investigated the possibility that the children's emotional and behavioral difficulties are associated with social information and attribution processing. Participants were children with…
What Is Lexical Proficiency? Some Answers from Computational Models of Speech Data
ERIC Educational Resources Information Center
Crossley, Scott A.; Salsbury, Tom; McNamara, Danielle S.; Jarvis, Scott
2011-01-01
Lexical proficiency, as a cognitive construct, is poorly understood. However, lexical proficiency is an important element of language proficiency and fluency, especially for second language (L2) learners. Lexical proficiency is also an important attribute of L2 academic achievement. Generally speaking, lexical proficiency comprises breadth of…
USDA-ARS?s Scientific Manuscript database
Aeromonad virulence remains poorly understood, and is difficult to predict from strain characteristics. In addition, infections are often polymicrobial (i.e., are mixed infections), and 5 -10% of such infections include two distinct aeromonads, which has an unknown impact on virulence. In this work,...
ERIC Educational Resources Information Center
Phillips, Brian N.
2011-01-01
Declining membership is a concerning, yet poorly understood issue affecting professional associations across many disciplines (Bauman, 2008). The discipline of rehabilitation counseling is experiencing membership decline even as the number of certified rehabilitation counselors continues to increase (Leahy, 2009). Little empirical research…
Contributions of hydrology to Vesicular Stomatitis Virus emergence in the Western United States
USDA-ARS?s Scientific Manuscript database
Relationships between environmental variables associated with the spread of vector-borne pathogens, such as RNA viruses transmitted to humans and animals, remain poorly understood. Vesicular stomatitis (VS) is caused by a vector-borne, zoonotic RNA virus (VSV), and is the most common vesicular dise...
Statistical Word Learning in Children with Autism Spectrum Disorder and Specific Language Impairment
ERIC Educational Resources Information Center
Haebig, Eileen; Saffran, Jenny R.; Ellis Weismer, Susan
2017-01-01
Background: Word learning is an important component of language development that influences child outcomes across multiple domains. Despite the importance of word knowledge, word-learning mechanisms are poorly understood in children with specific language impairment (SLI) and children with autism spectrum disorder (ASD). This study examined…
The role of CAX1 and CAX3 in elemental distribution and abundance in Arabidopsis seed
USDA-ARS?s Scientific Manuscript database
The ability to alter nutrient partitioning within plant cells is poorly understood. In Arabidopsis (Arabidopsis thaliana), a family of endomembrane cation exchangers (CAXs) transports Ca(2+) and other cations. However, experiments have not focused on how the distribution and partitioning of calcium ...
An Investigation of Factors Involved When Educational Psychologists sSupervise Other Professionals
ERIC Educational Resources Information Center
Callicott, Katie; Leadbetter, Jane
2013-01-01
Inter-professional supervision combines the social processes of supervision and multi-agency working: both complex and often poorly understood processes. This paper discusses the first author's research of inter-professional supervision, involving an educational psychologist (EP) supervising another professional and complements the recently…
Madrone duff and the natural regeneration of Douglas-fir.
Don Minore
1987-01-01
Excellent natural regeneration of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) often occurs under canopies of Pacific madrone (Arbutus menziesii Pursh), but the effects of madrone duff on regeneration are poorly understood. A field experiment was conducted in a thinned Douglas-fir stand in southwestern Oregon to see if...
Storage conditions affecting increase in falling number of soft red winter wheat grain
USDA-ARS?s Scientific Manuscript database
Falling number (FN) of wheat grain, a measure of preharvest sprouting, tends to increase during storage; however, grain and storage conditions that impact FN changes are poorly understood. Wheat grain samples of varying FN from several cultivars were obtained by malting, by incubating wheat stalks,...
Can Human Associated Bacteroides (HF183MGB) be used as a Pathogen Predictor in Urban Watersheds?
The fate and transport dynamics of fecal indicators and pathogenic microorganisms are poorly characterized in urban watersheds. Moreover, very little is understood about the actual relationship between fecal indicator bacteria (FIB) and the risk to public health. In this study we...
USDA-ARS?s Scientific Manuscript database
Atmospheric CO2 concentration will likely exceed 500 uL L-1 by 2050, often increasing plant community productivity in part by increasing abundance of species favored by increased CA. Whether increased abundance translates to increased inflorescence production is poorly understood, and is important ...
Homing success in wintering sparrows
C. John Ralph; L. Richard Mewaldt
1976-01-01
The ability of birds to return "home" after displacement is generallywell known but poorly understood because of the multiplicity of variablesthat affect homing performance. These variables can include age andprevious experience of the bird, as well as the timing and distance of thedisplacement. The phenomenon of homing is also difficult to interpretbecause,...
TOXICITY PATHWAY ANALYSIS IN AGING BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE
The influence of aging on susceptibility to environmental stressors is poorly understood. To investigate the contribution of different life stages on response to toxicants, we examined the effects of acute exposure by oral gavage of the volatile organic solvent toluene (0.00, 0.3...
Objectives: Changes in air temperature are associated with an increase in cardiovascular events, but the role of pro-coagulant and pro-inflammatory blood markers is still poorly understood. We investigated the association between air temperature and fibrinogen, plasminogen act...
Acute exposure to ambient fine particulate matter (PM2.5) is tied to cardiovascular morbidity and mortality, especially among those with prior cardiac injury. The mechanisms and pathophysiologic events precipitating these outcomes remain poorly understood but may involve inflamm...
Dysarthria and Friedreich's Ataxia: What Can Intelligibility Assessment Tell Us?
ERIC Educational Resources Information Center
Blaney, Bronagh; Hewlett, Nigel
2007-01-01
Background: Friedreich's ataxia is one of the most common hereditary disorders of the nervous system. Dysarthria is a pervasive symptom of Friedreich's ataxia, yet the clinical presentation of speech symptoms remains poorly understood, leaving clinicians without the evidence required to develop therapy interventions. Aims: The research reported…
Face Scanning Distinguishes Social from Communication Impairments in Autism
ERIC Educational Resources Information Center
Falck-Ytter, Terje; Fernell, Elisabeth; Gillberg, Christopher; Von Hofsten, Claes
2010-01-01
How closely related are the social and communicative impairments in Autism Spectrum Disorder (ASD)? Recent findings in typically developing children suggest that both types of impairment are highly heritable but have only moderate behavioural and genetic overlap. So far, their respective roles in social perception are poorly understood. Here we…
ERIC Educational Resources Information Center
Fryer, Luke K.; Vermunt, Jan D.
2018-01-01
Background: Contemporary models of student learning within higher education are often inclusive of processing and regulation strategies. Considerable research has examined their use over time and their (person-centred) convergence. The longitudinal stability/variability of learning strategy use, however, is poorly understood, but essential to…
USDA-ARS?s Scientific Manuscript database
The majority of research on savanna vegetation dynamics has focused on the coexistence of woody and herbaceous vegetation; interactions among woody plants in savannas are relatively poorly understood. We present data from a 10-year longitudinal study of spatially explicit growth patterns of woody ve...
Variable high pressure processing sensitivities for GII human noroviruses
USDA-ARS?s Scientific Manuscript database
Human norovirus (HuNoV) is the leading cause of foodborne diseases worldwide. High pressure processing (HPP) is one of the most promising non-thermal technologies for decontamination of viral pathogens in foods. However, the survival of HuNoVs by HPP is poorly understood because these viruses cann...
High pressure treatment of human norovirus-like particles: factors affecting destruction efficacy
USDA-ARS?s Scientific Manuscript database
Human norovirus (HuNoV) is the leading cause of foodborne diseases worldwide. High pressure processing (HPP) is considered a promising non-thermal technology to inactivate viral pathogens in foods. However, the effectiveness of HPP on inactivating HuNoV remains poorly understood because it cannot be...
The Reciprocity of "Imitative Learning" through Apprenticeship
ERIC Educational Resources Information Center
Chan, Selena
2017-01-01
Humans are proposed to have evolved to learn through observation, imitation and practice or mimesis. In this article, the contribution of imitation, as an important but poorly understood aspect of mimetic learning, is advocated to create affordances for dyadic learning. However, learning through imitation is often perceived with negative…
The Therapy Process Observational Coding System for Child Psychotherapy Strategies Scale
ERIC Educational Resources Information Center
McLeod, Bryce D.; Weisz, John R.
2010-01-01
Most everyday child and adolescent psychotherapy does not follow manuals that document the procedures. Consequently, usual clinical care has remained poorly understood and rarely studied. The Therapy Process Observational Coding System for Child Psychotherapy-Strategies scale (TPOCS-S) is an observational measure of youth psychotherapy procedures…
Discrimination and Sleep: The Protective Role of School Belonging
ERIC Educational Resources Information Center
Huynh, Virginia W.; Gillen-O'Neel, Cari
2016-01-01
Ethnic minority adolescents experience certain sleep problems, yet factors that affect their sleep are poorly understood. This study examined the association between ethnic discrimination and sleep during adolescence and the extent to which perceived stress mediated these associations. This study also examined whether school belonging can protect…
Global diversity and geography of soil fungi
Leho Tedersoo; Mohammad Bahram; Sergei Põlme; Urmas Kõljalg; Nourou S. Yorou; Ravi Wijesundera; Luis Villarreal Ruiz; Aida M. Vasco-Palacios; Pham Quang Thu; Ave Suija; Matthew E. Smith; Cathy Sharp; Erki Saluveer; Alessandro Saitta; Miguel Rosas; Taavi Riit; David Ratkowsky; Karin Pritsch; Kadri Põldmaa; Meike Piepenbring; Cherdchai Phosri; Marko Peterson; Kaarin Parts; Kadri Pärtel; Eveli Otsing; Eduardo Nouhra; André L. Njouonkou; R. Henrik Nilsson; Luis N. Morgado; Jordan Mayor; Tom W. May; Luiza Majukim; D. Jean Lodge; Su See Lee; Karl-Henrik Larsson; Petr Kohout; Kentaro Hosaka; Indrek Hiiesalu; Terry W. Henkel; Helery Harend; Liang-dong Guo; Alina Greslebin; Gwen Gretlet; Jozsef Geml; Genevieve Gates; William Dunstan; Chris Dunk; Rein Drenkhan; John Dearnaley; André De Kesel; Tan Dang; Xin Chen; Franz Buegger; Francis Q. Brearley; Gregory Bonito; Sten Anslan; Sandra Abell; Kessy Abarenkov
2014-01-01
Fungi play major roles in ecosystem processes, but the determinants of fungal diversity and biogeographic patterns remain poorly understood. Using DNA metabarcoding data from hundreds of globally distributed soil samples,we demonstrate that fungal richness is decoupled from plant diversity.The plant-to-fungus richness ratio declines exponentially toward the poles....
Climate variability drives population cycling and synchrony
Lars Y. Pomara; Benjamin Zuckerberg
2017-01-01
Aim There is mounting concern that climate change will lead to the collapse of cyclic population dynamics, yet the influence of climate variability on population cycling remains poorly understood. We hypothesized that variability in survival and fecundity, driven by climate variability at different points in the life cycle, scales up from...
Mosquito host choices on livestock amplifiers of Rift Valley fever virus in Kenya
USDA-ARS?s Scientific Manuscript database
Animal hosts may vary in their attraction and acceptability as components of the host location process for assessing biting rates of vectors and risk of exposure to pathogens. However, these parameters remain poorly understood for mosquito vectors of the Rift Valley fever (RVF), an arboviral disease...
The physicochemical properties of coarse-mode, iron-containing particles, and their temporal and spatial distributions are poorly understood. Single particle analysis combining x-ray elemental mapping and computer-controlled scanning electron microscopy (CCSEM-EDX) of passively ...
Modeling Spatial and Temporal Aspects of Visual Backward Masking
ERIC Educational Resources Information Center
Hermens, Frouke; Luksys, Gediminas; Gerstner, Wulfram; Herzog, Michael H.; Ernst, Udo
2008-01-01
Visual backward masking is a versatile tool for understanding principles and limitations of visual information processing in the human brain. However, the mechanisms underlying masking are still poorly understood. In the current contribution, the authors show that a structurally simple mathematical model can explain many spatial and temporal…
Tackling the Difficulties in Learning Evolution: Effects of Adaptive Self-Explanation Prompts
ERIC Educational Resources Information Center
Neubrand, Charlotte; Harms, Ute
2017-01-01
Teaching and learning evolution is challenging. Biology education research shows that the underlying evolutionary concepts are poorly understood among students. This prevents a meaningful understanding of the central biological concepts. The instructional format of self-explanation prompts seems to be promising to respond to these difficulties.…
Environmental enteric dysfunction and growth failure/stunting in global child health
USDA-ARS?s Scientific Manuscript database
Approximately 25% of the world's children aged <5 years have stunted growth, which is associated with increased mortality, cognitive dysfunction, and loss of productivity. Reducing by 40% the number of stunted children is a global target for 2030. The pathogenesis of stunting is poorly understood. P...
The Role of the Basolateral Amygdala in Punishment
ERIC Educational Resources Information Center
Dit-Bressel, Philip Jean-Richard; McNally, Gavan P.
2015-01-01
Aversive stimuli not only support fear conditioning to their environmental antecedents, they also punish behaviors that cause their occurrence. The amygdala, especially the basolateral nucleus (BLA), has been critically implicated in Pavlovian fear learning but its role in punishment remains poorly understood. Here, we used a within-subjects…
Depression and Relational Health in Asian American and European American College Women
ERIC Educational Resources Information Center
Lund, Terese J.; Chan, Pauline; Liang, Belle
2014-01-01
Research consistently demonstrates elevated rates of depression among college-aged women, yet evidence of racial differences in depression among this population are poorly understood. Moreover, the correlates of depression among Asian American women are also understudied. In this exploratory analysis, we examined mean differences in depression…
USDA-ARS?s Scientific Manuscript database
Despite their fundamental importance for growth, the mechanisms that regulate food intake are poorly understood. Our previous work demonstrated that insect sulfakinin (SK) signaling is involved in inhibiting feeding in an important model and pest insect, the red flour beetle Tribolium castaneum. B...
Soy protein isolate inhibits hepatic tumor promotion in mice fed a high-fat liquid diet
USDA-ARS?s Scientific Manuscript database
Alcoholic and nonalcoholic fatty liver disease are risk factors for development of hepatocellular carcinoma, but the underlying mechanisms are poorly understood. On the other hand, ingestion of soy-containing diets may oppose the development of certain cancers. We previously reported that replacing ...
The effects of exposure to volatile organic compounds (VOCs), which are of concern to the EPA, are poorly understood, in part because of insufficient characterization of how human exposure duration impacts VOC effects. Two inhalation studies with multiple endpoints, one acute an...
The Importance of Allochthonous Subsidies to an Estuarine Food Web along a Salinity Gradient
Estuarine food webs function within a heterogeneous mosaic and are supported by a mix of primary producers from both local and distant sources. Processes governing the exchange and consumption of organic matter (OM), however, are poorly understood. To study the contribution of ...
Metabolic coevolution in the bacterial symbiosis of whiteflies and related plant sap-feeding insects
USDA-ARS?s Scientific Manuscript database
In animals dependent on intracellular bacteria with very small genomes, the host cell is adapted to support the function of its bacterial symbionts, but the molecular basis of these adaptations is poorly understood. We investigated the metabolic coevolution between the whitefly Bemisia tabaci and th...
How Do Teachers View Their Own Pedagogical Authority?
ERIC Educational Resources Information Center
Harjunen, Elina
2009-01-01
Authority, a fundamental part of the teaching-studying-learning process, is a problematic and poorly understood component of classroom life. It can be said, in practical terms, that pedagogical authority is constructed in classrooms, in teacher-student interaction and in the spirit of their physical presence, confidence, appreciation,…
Exposure to disinfection by-products (DBPs) has been associated with cancer risk, but the mechanisms of action are poorly understood. A recent study found increased bladder cancer risk among subjects attending swimming pools, where uptake of DBPs, such as trihalomethanes (THMs) c...
USDA-ARS?s Scientific Manuscript database
The carotenoid biosynthetic pathway regulatory mechanisms leading to lycopene accumulation are well defined in the model fruit, tomato (Lycopersicon esculentum L.). The regulatory mechanisms leading to accumulation of other carotenoids and flesh colors, however, are poorly understood. The variety ...
Improved methods for measuring and assessing microenvironmental exposure in individuals are needed. How human activities affect particulate matter in the personal cloud is poorly understood. A quality assurance tool to aid the study of particle transport mechanisms (e.g., re-en...
USDA-ARS?s Scientific Manuscript database
The detailed mechanistic aspects for the final starch digestion process leading to effective alpha-glucogenesis by the 2 mucosal alpha-glucosidases, human sucrase-isomaltase complex (SI) and human maltase-glucoamylase (MGAM), are poorly understood. This is due to the structural complexity and vast v...
Evidence of a sewer vapor transport pathway at the USEPA vapor intrusion research duplex
The role of sewer lines as preferential pathways for vapor intrusion is poorly understood. Although the importance of sewer lines for volatile organic compound (VOC) transport has been documented at a small number of sites with vapor intrusion, sewer lines are not routinely sampl...
Variations in Cognitive Maps: Understanding Individual Differences in Navigation
ERIC Educational Resources Information Center
Weisberg, Steven M.; Schinazi, Victor R.; Newcombe, Nora S.; Shipley, Thomas F.; Epstein, Russell A.
2014-01-01
There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to…
USDA-ARS?s Scientific Manuscript database
The networks that govern carbon metabolism and control intracellular carbon partitioning in photosynthetic cells are poorly understood. Target of rapamycin (TOR) kinase is a conserved growth regulator that integrates nutrient signals and modulates cell growth in eukaryotes, though the TOR signaling ...
Altered White Matter Microstructure in Adolescents with Major Depression: A Preliminary Study
ERIC Educational Resources Information Center
Cullen, Kathryn R.; Klimes-Dougan, Bonnie; Muetzel, Ryan; Mueller, Bryon A.; Camchong, Jazmin; Houri, Alaa; Kurma, Sanjiv; Lim, Kelvin O.
2010-01-01
Objective: Major depressive disorder (MDD) occurs frequently in adolescents, but the neurobiology of depression in youth is poorly understood. Structural neuroimaging studies in both adult and pediatric populations have implicated frontolimbic neural networks in the pathophysiology of MDD. Diffusion tensor imaging (DTI), which measures white…
EFFECTS OF TOLUENE ON BRAIN OXIDATIVE STRESS PARAMETERS IN AGING BROWN NORWAY RATS
Aging-related susceptibility to environmental chemicals is poorly understood. Oxidative stress (OS) appears to play an important role in susceptibility and disease in old age. The objectives of this study, therefore, were to test whether OS is a potential toxicity pathway for tol...
Social Motor Synchronization: Insights for Understanding Social Behavior in Autism
ERIC Educational Resources Information Center
Fitzpatrick, Paula; Romero, Veronica; Amaral, Joseph L.; Duncan, Amie; Barnard, Holly; Richardson, Michael J.; Schmidt, R. C.
2017-01-01
Impairments in social interaction and communication are critical features of ASD but the underlying processes are poorly understood. An under-explored area is the social motor synchronization that happens when we coordinate our bodies with others. Here, we explored the relationships between dynamical measures of social motor synchronization and…
In vitro downregulated hypoxia transcriptome is associated with poor prognosis in breast cancer.
Abu-Jamous, Basel; Buffa, Francesca M; Harris, Adrian L; Nandi, Asoke K
2017-06-15
Hypoxia is a characteristic of breast tumours indicating poor prognosis. Based on the assumption that those genes which are up-regulated under hypoxia in cell-lines are expected to be predictors of poor prognosis in clinical data, many signatures of poor prognosis were identified. However, it was observed that cell line data do not always concur with clinical data, and therefore conclusions from cell line analysis should be considered with caution. As many transcriptomic cell-line datasets from hypoxia related contexts are available, integrative approaches which investigate these datasets collectively, while not ignoring clinical data, are required. We analyse sixteen heterogeneous breast cancer cell-line transcriptomic datasets in hypoxia-related conditions collectively by employing the unique capabilities of the method, UNCLES, which integrates clustering results from multiple datasets and can address questions that cannot be answered by existing methods. This has been demonstrated by comparison with the state-of-the-art iCluster method. From this collection of genome-wide datasets include 15,588 genes, UNCLES identified a relatively high number of genes (>1000 overall) which are consistently co-regulated over all of the datasets, and some of which are still poorly understood and represent new potential HIF targets, such as RSBN1 and KIAA0195. Two main, anti-correlated, clusters were identified; the first is enriched with MYC targets participating in growth and proliferation, while the other is enriched with HIF targets directly participating in the hypoxia response. Surprisingly, in six clinical datasets, some sub-clusters of growth genes are found consistently positively correlated with hypoxia response genes, unlike the observation in cell lines. Moreover, the ability to predict bad prognosis by a combined signature of one sub-cluster of growth genes and one sub-cluster of hypoxia-induced genes appears to be comparable and perhaps greater than that of known hypoxia signatures. We present a clustering approach suitable to integrate data from diverse experimental set-ups. Its application to breast cancer cell line datasets reveals new hypoxia-regulated signatures of genes which behave differently when in vitro (cell-line) data is compared with in vivo (clinical) data, and are of a prognostic value comparable or exceeding the state-of-the-art hypoxia signatures.
Reassessing immune control of hepatitis A virus.
Walker, Christopher M; Feng, Zongdi; Lemon, Stanley M
2015-04-01
There is renewed interest in hepatitis A virus (HAV) pathogenesis and immunity after 2-3 decades of limited progress. From a public health perspective, the average age at infection has increased in developing countries, resulting in more severe hepatitis that is poorly understood mechanistically. More fundamentally, there is interest in comparing immunity to HAV and hepatitis C virus (HCV): small, positive-strand RNA viruses with very different infection outcomes. Here, we review evidence that circulating HAV virions are cloaked in membranes, with consequences for induction of innate immunity and antibody-mediated neutralization. We also consider the contribution of CD4+ helper versus CD8+ cytotoxic T cells to antiviral immunity and liver injury, and present a model of non-cytotoxic immune control of HAV infection. Copyright © 2015 Elsevier B.V. All rights reserved.
Studies of the Coldest Brown Dwarfs With The James Webb Space Telescope
NASA Astrophysics Data System (ADS)
Roellig, Thomas L.; Greene, Thomas P.; Beichman, Charles; Meyer, Michael; Rieke, Marcia
2016-07-01
The coolest T and Y-class Brown Dwarf objects are very faint and are therefore very poorly understood, since they are barely detectable with the current astronomical instrumentation. The upcoming James Webb Space Telescope now in development for a launch in the Fall of 2018 will have vastly increased sensitivity in the near and mid-infrared compared to any current facilities and will not be affected by telluric absorption over its entire wavelength range of operations. As a result it will be an ideal tool to obtain information about the composition and temperature-pressure structure in these objects' atmospheres. This presentation outlines the JWST guaranteed time observing plans for these studies. These plans comprise both spectro-photometric and spectroscopic observations of a selection of late T and Y-dwarf targets.
Silencing of ATP11B by RNAi-Induced Changes in Neural Stem Cell Morphology.
Wang, Jiao; Wang, Qian; Zhou, Fangfang; Wang, Dong; Wen, Tieqiao
2017-01-01
RNA interference (RNAi) technology is one of the main research tools in many studies of neural stem cells. This study describes effects of ATP11B on the morphology change of neural stem cells by using RNAi. ATP11B belongs to P4-ATPases family, which is preferential translocate phosphatidylserine of cell membrane. Although it exists in neural stem cells, its physiological function is poorly understood. By using RNAi technology to downregulate expression of ATP11B, we found distinct morphological changes in neural stem cells. More important, psiRNA-ATP11B-transfected cells displayed short neurite outgrowth compared to the control cells. These data strongly suggest that ATP11B plays a key role in the morphological change of neural stem cells.
NASA Astrophysics Data System (ADS)
Lin, Neil Y. C.; Bierbaum, Matthew; Cohen, Itai
2017-09-01
By combining confocal microscopy and stress assessment from local structural anisotropy, we directly measure stresses in 3D quiescent colloidal liquids. Our noninvasive and nonperturbative method allows us to measure forces ≲50 fN with a small and tunable probing volume, enabling us to resolve the stress fluctuations arising from particle thermal motions. We use the Green-Kubo relation to relate these measured stress fluctuations to the bulk Brownian viscosity at different volume fractions, comparing against simulations and conventional rheometry measurements. We find that the Green-Kubo analysis gives excellent agreement with these prior results, suggesting that similar methods could be applied to investigations of local flow properties in many poorly understood far-from-equilibrium systems, including suspensions that are glassy, strongly sheared, or highly confined.
Probiotic Bacteria Induce a ‘Glow of Health’
Smillie, Christopher; Varian, Bernard J.; Ibrahim, Yassin M.; Lakritz, Jessica R.; Alm, Eric J.; Erdman, Susan E.
2013-01-01
Radiant skin and hair are universally recognized as indications of good health. However, this ‘glow of health’ display remains poorly understood. We found that feeding of probiotic bacteria to aged mice induced integumentary changes mimicking peak health and reproductive fitness characteristic of much younger animals. Eating probiotic yogurt triggered epithelial follicular anagen-phase shift with sebocytogenesis resulting in thick lustrous fur due to a bacteria-triggered interleukin-10-dependent mechanism. Aged male animals eating probiotics exhibited increased subcuticular folliculogenesis, when compared with matched controls, yielding luxuriant fur only in probiotic-fed subjects. Female animals displayed probiotic-induced hyperacidity coinciding with shinier hair, a feature that also aligns with fertility in human females. Together these data provide insights into mammalian evolution and novel strategies for integumentary health. PMID:23342023
On the generation of solar spicules and Alfvénic waves
NASA Astrophysics Data System (ADS)
Martínez-Sykora, J.; De Pontieu, B.; Hansteen, V. H.; Rouppe van der Voort, L.; Carlsson, M.; Pereira, T. M. D.
2017-06-01
In the lower solar atmosphere, the chromosphere is permeated by jets known as spicules, in which plasma is propelled at speeds of 50 to 150 kilometers per second into the corona. The origin of the spicules is poorly understood, although they are expected to play a role in heating the million-degree corona and are associated with Alfvénic waves that help drive the solar wind. We compare magnetohydrodynamic simulations of spicules with observations from the Interface Region Imaging Spectrograph and the Swedish 1-m Solar Telescope. Spicules are shown to occur when magnetic tension is amplified and transported upward through interactions between ions and neutrals or ambipolar diffusion. The tension is impulsively released to drive flows, heat plasma (through ambipolar diffusion), and generate Alfvénic waves.
Reineck, Philipp; Lau, Desmond W M; Wilson, Emma R; Nunn, Nicholas; Shenderova, Olga A; Gibson, Brant C
2018-02-06
Detonation nanodiamonds are of vital significance to many areas of science and technology. However, their fluorescence properties have rarely been explored for applications and remain poorly understood. We demonstrate significant fluorescence from the visible to near-infrared spectral regions from deaggregated, single-digit detonation nanodiamonds dispersed in water produced via post-synthesis oxidation. The excitation wavelength dependence of this fluorescence is analyzed in the spectral region from 400 nm to 700 nm as well as the particles' absorption characteristics. We report a strong pH dependence of the fluorescence and compare our results to the pH dependent fluorescence of aromatic hydrocarbons. Our results significantly contribute to the current understanding of the fluorescence of carbon-based nanomaterials in general and detonation nanodiamonds in particular.
Ueki, Hiroshi; Wang, I-Hsuan; Fukuyama, Satoshi; Katsura, Hiroaki; da Silva Lopes, Tiago Jose; Neumann, Gabriele; Kawaoka, Yoshihiro
2018-06-25
The pathophysiological changes that occur in lungs infected with influenza viruses are poorly understood. Here we established an in vivo imaging system that combines two-photon excitation microscopy and fluorescent influenza viruses of different pathogenicity. This approach allowed us to monitor and correlate several parameters and physiological changes including the spread of infection, pulmonary permeability, pulmonary perfusion speed, number of recruited neutrophils in infected lungs, and neutrophil motion in the lungs of live mice. Several physiological changes were larger and occurred earlier in mice infected with a highly pathogenic H5N1 influenza virus compared with those infected with a mouse-adapted human strain. These findings demonstrate the potential of our in vivo imaging system to provide novel information about the pathophysiological consequences of virus infections.
Macrophage Activation Mechanisms in Human Monocytic Cell Line-derived Macrophages.
Sumiya, Yu; Ishikawa, Mami; Inoue, Takahiro; Inui, Toshio; Kuchiike, Daisuke; Kubo, Kentaro; Uto, Yoshihiro; Nishikata, Takahito
2015-08-01
Although the mechanisms of macrophage activation are important for cancer immunotherapy, they are poorly understood. Recently, easy and robust assay systems for assessing the macrophage-activating factor (MAF) using monocytic cell line-derived macrophages were established. Gene-expression profiles of U937- and THP-1-derived macrophages were compared using gene expression microarray analysis and their responses against several MAFs were examined by in vitro experiments. Activated states of these macrophages could not be assigned to a specific sub-type but showed, however, different unique characteristics. The unique of monocytic cell line-derived macrophages could provide clues to understand the activation mechanism of macrophages and, therefore, help to develop effective cancer immunotherapy with MAFs. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.
Optimal chemotactic responses in stochastic environments
Godány, Martin
2017-01-01
Although the “adaptive” strategy used by Escherichia coli has dominated our understanding of bacterial chemotaxis, the environmental conditions under which this strategy emerged is still poorly understood. In this work, we study the performance of various chemotactic strategies under a range of stochastic time- and space-varying attractant distributions in silico. We describe a novel “speculator” response in which the bacterium compare the current attractant concentration to the long-term average; if it is higher then they tumble persistently, while if it is lower than the average, bacteria swim away in search of more favorable conditions. We demonstrate how this response explains the experimental behavior of aerobically-grown Rhodobacter sphaeroides and that under spatially complex but slowly-changing nutrient conditions the speculator response is as effective as the adaptive strategy of E. coli. PMID:28644830
Runeson-Broberg, Roma; du Prel, Jean-Baptist; Westerholm, Peter; Nordin, Maria; Knutsson, Anders; Alfredsson, Lars; Fahlén, Göran; Peter, Richard
2017-01-01
In aging societies, zest for work may be pivotal when deciding to stay occupationally active longer. Psychosocial work stress is a prevalent public health problem and may have an impact on zest for work. Work over-commitment (WOC) is a personal coping strategy for work stress with excessive striving and a health risk. However, the long-term effect of WOC on zest for work is poorly understood. To investigate the age-related associations of work over-commitment with zest for work. During 1996-1998 and 2000-2003, predominantly industrial workers (n = 2940) participated in the WOLF-Norrland study and responded to a questionnaire referring to socio-demographics, WOC, zest for work, effort-reward imbalance proxies, and mental health. Age-adjusted multiple logistic regressions were performed with original and imputed datasets. Cross-sectionally, work overcommitted middle-aged employees had an increased prevalence of poor zest for work compared to their contemporaries without WOC (OR: 3.74 [95%-CI 2.19; 6.40]). However, in a longitudinal analysis associations between onset of 'poor zest for work' and the WOC subscales 'need for approval' (OR: 3.29 [95%-CI 1.04; 10.37]) and 'inability to withdraw from work' (OR: 5.14 [95%-CI 1.32; 20.03]) were observed. The longitudinal findings among older employees could be relevant regarding the expected need to remain occupationally active longer.
The effects of caffeine on the cholinergic system.
Pohanka, Miroslav
2014-01-01
Caffeine is a secondary metabolite of tea and coffee plants. It is the active psychostimulant ingredient of widely consumed beverages, chocolate and some drugs as well. The major pathways for caffeine including interaction with adenosine receptors have been identified but caffeine has several minor pathways as well that remain poorly understood including the cholinergic system. Given the role of caffeine in the cholinergic system, some molecular targets have been tracked and a mechanism of its action has been proposed in research studies. However, the biological effect of caffeine on the cholinergic system is not completely understood. The present review focuses on the role of caffeine in the cholinergic system.
Bertrand, Josie-Anne; Bedetti, Christophe; Postuma, Ronald B; Monchi, Oury; Génier Marchand, Daphné; Jubault, Thomas; Gagnon, Jean-François
2012-12-01
Color discrimination deficit is a common nonmotor manifestation of Parkinson's disease (PD). However, the pathophysiology of this dysfunction remains poorly understood. Although retinal structure changes found in PD have been suggested to cause color discrimination deficits, the impact of cognitive impairment and cortical alterations remains to be determined. We investigated the contribution of cognitive impairment to color discrimination deficits in PD and correlated them with cortical anomalies. Sixty-six PD patients without dementia and 20 healthy controls performed the Farnsworth-Munsell 100 hue test and underwent a comprehensive neuropsychological assessment for mild cognitive impairment diagnosis. In a subgroup of 26 PD patients, we also used high-definition neuroanatomical magnetic resonance imaging for cortical thickness and diffusion tensor analysis. PD patients with mild cognitive impairment performed poorly on the Farnsworth-Munsell 100 hue test compared with PD patients without mild cognitive impairment and controls. In PD patients, performance on the Farnsworth-Munsell 100 hue test was correlated with measures of visuospatial abilities and executive functions. Neuroimaging analysis revealed higher mean and radial diffusivity values in right posterior white-matter structures that correlated with poor performance on the Farnsworth-Munsell 100 hue test. No cortical thickness correlation reached significance. This study showed that cognitive impairment makes a major contribution to the color discrimination deficits reported in PD. Thus, performance on the Farnsworth-Munsell 100 hue test may reflect cognitive impairment more than color discrimination deficits in PD. Poor performance on the Farnsworth-Munsell 100 hue test was also associated with white-matter alterations in right posterior brain regions. Copyright © 2012 Movement Disorder Society.
Unveiling a phytoplankton hotspot at a narrow boundary between coastal and offshore waters
Ribalet, Francois; Marchetti, Adrian; Hubbard, Katherine A.; Brown, Kristina; Durkin, Colleen A.; Morales, Rhonda; Robert, Marie; Swalwell, Jarred E.; Tortell, Philippe D.; Armbrust, E. Virginia
2010-01-01
In terrestrial ecosystems, transitional areas between different plant communities (ecotones) are formed by steep environmental gradients and are commonly characterized by high species diversity and primary productivity, which in turn influences the foodweb structure of these regions. Whether comparable zones of elevated diversity and productivity characterize ecotones in the oceans remains poorly understood. Here we describe a previously hidden hotspot of phytoplankton diversity and productivity in a narrow but seasonally persistent transition zone at the intersection of iron-poor, nitrate-rich offshore waters and iron-rich, nitrate-poor coastal waters of the Northeast Pacific Ocean. Novel continuous measurements of phytoplankton cell abundance and composition identified a complex succession of blooms of five distinct size classes of phytoplankton populations within a 100-km–wide transition zone. The blooms appear to be fueled by natural iron enrichment of offshore communities as they are transported toward the coast. The observed succession of phytoplankton populations is likely driven by spatial gradients in iron availability or time since iron enrichment. Regardless of the underlying mechanism, the resulting communities have a strong impact on the regional biogeochemistry as evidenced by the low partial pressure of CO2 and the nearly complete depletion of nutrients. Enhanced phytoplankton productivity and diversity associated with steep environmental gradients are expected wherever water masses with complementary nutrient compositions mix to create a region more favorable for phytoplankton growth. The ability to detect and track these important but poorly characterized marine ecotones is critical for understanding their impact on productivity and ecosystem structure in the oceans. PMID:20823224
Unveiling a phytoplankton hotspot at a narrow boundary between coastal and offshore waters.
Ribalet, Francois; Marchetti, Adrian; Hubbard, Katherine A; Brown, Kristina; Durkin, Colleen A; Morales, Rhonda; Robert, Marie; Swalwell, Jarred E; Tortell, Philippe D; Armbrust, E Virginia
2010-09-21
In terrestrial ecosystems, transitional areas between different plant communities (ecotones) are formed by steep environmental gradients and are commonly characterized by high species diversity and primary productivity, which in turn influences the foodweb structure of these regions. Whether comparable zones of elevated diversity and productivity characterize ecotones in the oceans remains poorly understood. Here we describe a previously hidden hotspot of phytoplankton diversity and productivity in a narrow but seasonally persistent transition zone at the intersection of iron-poor, nitrate-rich offshore waters and iron-rich, nitrate-poor coastal waters of the Northeast Pacific Ocean. Novel continuous measurements of phytoplankton cell abundance and composition identified a complex succession of blooms of five distinct size classes of phytoplankton populations within a 100-km-wide transition zone. The blooms appear to be fueled by natural iron enrichment of offshore communities as they are transported toward the coast. The observed succession of phytoplankton populations is likely driven by spatial gradients in iron availability or time since iron enrichment. Regardless of the underlying mechanism, the resulting communities have a strong impact on the regional biogeochemistry as evidenced by the low partial pressure of CO(2) and the nearly complete depletion of nutrients. Enhanced phytoplankton productivity and diversity associated with steep environmental gradients are expected wherever water masses with complementary nutrient compositions mix to create a region more favorable for phytoplankton growth. The ability to detect and track these important but poorly characterized marine ecotones is critical for understanding their impact on productivity and ecosystem structure in the oceans.
Katsos, Napoleon; Roqueta, Clara Andrés; Estevan, Rosa Ana Clemente; Cummins, Chris
2011-04-01
Specific Language Impairment (SLI) is understood to be a disorder that predominantly affects phonology, morphosyntax and/or lexical semantics. There is little conclusive evidence on whether children with SLI are challenged with regard to Gricean pragmatic maxims and on whether children with SLI are competent with the logical meaning of quantifying expressions. We use the comprehension of statements quantified with 'all', 'none', 'some', 'some…not', 'most' and 'not all' as a paradigm to study whether Spanish-speaking children with SLI are competent with the pragmatic maxim of informativeness, as well as with the logical meaning of these expressions. Children with SLI performed more poorly than a group of age-matched typically-developing peers, and both groups performed more poorly with pragmatics than with logical meaning. Moreover, children with SLI were disproportionately challenged by pragmatic meaning compared to their age-matched peers. However, the performance of children with SLI was comparable to that of a group of younger language-matched typically-developing children. The findings document that children with SLI do face difficulties with employing the maxim of informativeness, as well as with understanding the logical meaning of quantifiers, but also that these difficulties are in keeping with their overall language difficulties rather than exceeding them. The implications of these findings for SLI, linguistic theory, and clinical practice are discussed. Copyright © 2010 Elsevier B.V. All rights reserved.
Observation of sandhill cranes' (Grus canadensis) flight behavior in heavy fog
Kirsch, Eileen M.; Wellik, Mike J.; Suarez, Manuel J.; Diehl, Robert H.; Lutes, Jim; Woyczik, Wendy; Krapfl, Jon; Sojda, Richard S.
2015-01-01
The behaviors of birds flying in low visibility conditions remain poorly understood. We had the opportunity to monitor Sandhill Cranes (Grus canadensis) flying in heavy fog with very low visibility during a comprehensive landscape use study of refuging cranes in the Horicon Marsh in southeastern Wisconsin. As part of the study, we recorded flight patterns of cranes with a portable marine radar at various locations and times of day, and visually counted cranes as they departed the roost in the morning. We compared flight patterns during a fog event with those recorded during clear conditions. In good visibility, cranes usually departed the night roost shortly after sunrise and flew in relatively straight paths toward foraging areas. In fog, cranes departed the roost later in the day, did not venture far from the roost, engaged in significantly more circling flight, and returned to the roost site rather than proceeding to foraging areas. We also noted that compared to mornings with good visibility, cranes flying in fog called more frequently than usual. The only time in this 2-year study that observers heard young of the year calling was during the fog event. The observed behavior of cranes circling and lingering in an area while flying in poor visibility conditions suggests that such situations may increase chances of colliding with natural or anthropogenic obstacles in the vicinity.
Lee, Chun Geun; Herzog, Erica L.; Ahangari, Farida; Zhou, Yang; Gulati, Mridu; Lee, Chang-Min; Peng, Xueyan; Feghali-Bostwick, Carol; Jimenez, Sergio A.; Varga, John; Elias, Jack A.
2014-01-01
Interstitial lung disease (ILD) with pulmonary fibrosis is an important manifestation in systemic sclerosis (SSc, scleroderma) where it portends a poor prognosis. However, biomarkers that predict the development and or severity of SSc-ILD have not been validated, and the pathogenetic mechanisms that engender this pulmonary response are poorly understood. In this study, we demonstrate in two different patient cohorts that the levels of chitotriosidase (Chit1) bioactivity and protein are significantly increased in the circulation and lungs of SSc patients compared with demographically matched controls. We also demonstrate that, compared with patients without lung involvement, patients with ILD show high levels of circulating Chit1 activity that correlate with disease severity. Murine modeling shows that in comparison with wild-type mice, bleomycin-induced pulmonary fibrosis was significantly reduced in Chit1−/− mice and significantly enhanced in lungs from Chit1 overexpressing transgenic animals. In vitro studies also demonstrated that Chit1 interacts with TGF-β1 to augment fibroblast TGF-β receptors 1 and 2 expression and TGF-β–induced Smad and MAPK/ERK activation. These studies indicate that Chit1 is potential biomarker for ILD in SSc and a therapeutic target in SSc-associated lung fibrosis and demonstrate that Chit1 augments TGF-β1 effects by increasing receptor expression and canonical and noncanonical TGF-β1 signaling. PMID:22826322
Nutrient adequacy and diet quality in low-income Hispanic Children – The VIVA LA FAMILIA Study
USDA-ARS?s Scientific Manuscript database
The role of nutrient adequacy and diet quality in the etiology of childhood obesity is poorly understood. Epidemiological studies have suggested that low-cost, energy dense diets high in grains, added sugars, and fat contribute to the development of obesity, especially in low-income groups. The spec...
Cue-Dependent Interference in Comprehension
ERIC Educational Resources Information Center
Van Dyke, Julie A.; McElree, Brian
2011-01-01
The role of interference as a primary determinant of forgetting in memory has long been accepted, however its role as a contributor to poor comprehension is just beginning to be understood. The current paper reports two studies, in which speed-accuracy tradeoff and eye-tracking methodologies were used with the same materials to provide converging…
USDA-ARS?s Scientific Manuscript database
The response of soil microbial communities following soil disturbances is poorly understood. The development of soil microbial communities in two restoration gradients was studied to investigate the impact of land-management regime at the W. K. Kellogg Biological Station, Michigan. The first restora...
Brainstem Transcription of Speech Is Disrupted in Children with Autism Spectrum Disorders
ERIC Educational Resources Information Center
Russo, Nicole; Nicol, Trent; Trommer, Barbara; Zecker, Steve; Kraus, Nina
2009-01-01
Language impairment is a hallmark of autism spectrum disorders (ASD). The origin of the deficit is poorly understood although deficiencies in auditory processing have been detected in both perception and cortical encoding of speech sounds. Little is known about the processing and transcription of speech sounds at earlier (brainstem) levels or…
The Multiple Subfunctions of Attention: Differential Developmental Gateways to Literacy and Numeracy
ERIC Educational Resources Information Center
Steele, Ann; Karmiloff-Smith, Annette; Cornish, Kim; Scerif, Gaia
2012-01-01
Attention is construed as multicomponential, but the roles of its distinct subfunctions in shaping the broader developing cognitive landscape are poorly understood. The current study assessed 3- to 6-year-olds (N = 83) to: (a) trace developmental trajectories of attentional processes and their structure in early childhood and (b) measure the…
USDA-ARS?s Scientific Manuscript database
Introductions of biocontrol beetles (tamarisk beetles) are causing dieback of exotic tamarisk in riparian zones across the western U.S., yet factors that determine plant communities that follow tamarisk dieback are poorly understood. Tamarisk-dominated soils are generally higher in nutrients, organi...
Fasting the Microbiota to Improve Metabolism?
Haas, Joel T; Staels, Bart
2017-10-03
While intermittent or periodic fasting provides a variety of favorable health benefits, the molecular mediators of these effects are poorly understood. In this issue of Cell Metabolism, Li and colleagues (2017) highlight the role of gut microbiota in mediating benefits of intermittent fasting through activation of adipose tissue beiging. Copyright © 2017. Published by Elsevier Inc.
Jacob M. Griffin; Monica G. Turner; Martin Simard
2011-01-01
Widespread bark beetle outbreaks are currently affecting multiple conifer forest types throughout western North America, yet many ecosystem-level consequences of this disturbance are poorly understood. We quantified the effect of mountain pine beetle (Dendroctonus ponderosae) outbreak on nitrogen (N) cycling through litter, soil, and vegetation in...
The consensus among environmental scientists and risk assessors is that the fate and effects of pharmaceutical and personal care products (PPCPS) in the environment are poorly understood. Many classes of PPCPs have yet to be investigated. Acquisition of trends data for a suite of...
Length of efficacy for control of curly top in sugar beet with seed foliar insecticides
USDA-ARS?s Scientific Manuscript database
Curly top in sugar beet caused by Beet curly top virus (BCTV) is an important yield limiting disease that can be reduced via neonicotinoid and pyrethroid insecticides. However the length of efficacy of these insecticides is poorly understood, so a series of field experiments was conducted with the ...
Chapter 1: The cactus ferruginous pygmy-owl: Taxonomy, distribution, and natural history
Jean-Luc E. Cartron; W. Scott Richardson; Glenn A. Proudfoot
2000-01-01
The cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) is a small, cryptic owl that is often difficult to observe. Its natural history and conservation needs are poorly understood. Despite ongoing research in Texas and Arizona, the available information remains limited. In addition, factors influencing demographics (e.g., habitat...
ERIC Educational Resources Information Center
Gase, Lauren N.; Robles, Brenda; Barragan, Noel C.; Kuo, Tony
2014-01-01
Although consumption of sugar-sweetened beverages (SSBs) is associated with many negative health outcomes, including obesity, diabetes, and cardiovascular disease, the relationship between consumer nutritional knowledge and the amount consumed is poorly understood. The objective of this study was to examine the relationship between knowledge of…
ERIC Educational Resources Information Center
Wishart, J. G.; Cebula, K. R.; Willis, D. S.; Pitcairn, T. K.
2007-01-01
Background: Interpreting emotional expressions is a socio-cognitive skill central to interpersonal interaction. Poor emotion recognition has been reported in autism but is less well understood in other kinds of intellectual disabilities (ID), with procedural differences making comparisons across studies and syndromes difficult. This study aimed to…
ERIC Educational Resources Information Center
Grygiel, Pawel; Switaj, Piotr; Anczewska, Marta; Humenny, Grzegorz; Rebisz, Slawomir; Sikorska, Justyna
2013-01-01
It is widely acknowledged that loneliness and depression are prevalent among university students and may contribute to poor academic achievements or higher probability of dropping out of university. However, the associations between these two phenomena are complex and not fully understood. In this paper we describe preliminary findings from a…
Heritability of Creative Achievement
ERIC Educational Resources Information Center
Piffer, Davide; Hur, Yoon-Mi
2014-01-01
Although creative achievement is a subject of much attention to lay people, the origin of individual differences in creative accomplishments remain poorly understood. This study examined genetic and environmental influences on creative achievement in an adult sample of 338 twins (mean age = 26.3 years; SD = 6.6 years). Twins completed the Creative…
Jeremy J. Burdon; Peter H. Thrall; Adnane Nemri
2012-01-01
Natural plant-pathogen associations are complex interactions in which the interplay of environment, host, and pathogen factors results in spatially heterogeneous ecological and epidemiological dynamics. The evolutionary patterns that result from the interaction of these factors are still relatively poorly understood. Recently, integration of the appropriate spatial and...
Academic Performance of Transfer Versus "Native" Students in Natural Resources & Sciences
ERIC Educational Resources Information Center
Johnson, Matthew D.
2005-01-01
Transfer students comprise a substantial component of the student body in many 4-year academic colleges, but the factors affecting students' success once they have transferred are poorly understood. Using data from standard university records, academic performance was examined for 2,467 students enrolled in natural resource majors at a mid-sized…
AGE-RELATED TOXICITY PATHWAY ANALYSIS IN BROWN NORWAY RAT BRAIN FOLLOWING ACUTE TOLUENE EXPOSURE
The influence of aging on susceptibility to environmental exposures is poorly understood. To investigate-the contribution of different life stages on response to toxicants, we examined the effects of an acute exposure to the volatile organic compound, toluene (0.0 or 1.0 g/kg), i...
Context Modulates Attention to Social Scenes in Toddlers with Autism
ERIC Educational Resources Information Center
Chawarska, Katarzyna; Macari, Suzanne; Shic, Frederick
2012-01-01
Background: In typical development, the unfolding of social and communicative skills hinges upon the ability to allocate and sustain attention toward people, a skill present moments after birth. Deficits in social attention have been well documented in autism, though the underlying mechanisms are poorly understood. Methods: In order to parse the…
The effects of anthropogenic contaminants on Gulf of Mexico plant communities are poorly understood despite the declining number of seagrass communities and wetland habitats. This presentation focuses on the second phase of a multi-year study designed to determine the role of su...
Structure of the mouthparts of Frankliniella bispinosa (Morgan) (Thysanoptera: Thripidae)
Carl C. Childers; Diann S. Achor
1991-01-01
Thrips are increasingly recognized as potentially serious pests in a number of different agricultural, ornamental and sylvan commodities worldwide as indicated by the papers presented at this conference. The small size of thrips, their large numbers, capacity for flight and wind dispersal, wide host ranges, poorly understood life histories and probable potential for...
USDA-ARS?s Scientific Manuscript database
Mammary stromal adipocytes constitute an active site for the synthesis of the adipokine adiponectin (APN) that may influence the mammary epithelial microenvironment. The relationship between 'local', mammary tissue-derived APN and breast cancer risk is poorly understood. Herein, we identify a novel ...
The Impact of Threat of Shock-Induced Anxiety on Memory Encoding and Retrieval
ERIC Educational Resources Information Center
Bolton, Sorcha; Robinson, Oliver J.
2017-01-01
Anxiety disorders are the most common mental health disorders, and daily transient feelings of anxiety (or "stress") are ubiquitous. However, the precise impact of both transient and pathological anxiety on higher-order cognitive functions, including short- and long-term memory, is poorly understood. A clearer understanding of the…
Spatial and temporal controls on watershed ecohydrology in the northern Rocky Mountains
Ryan E. Emanuel; Howard E. Epstein; Brian L. McGlynn; Daniel L. Welsch; Daniel J. Muth; Paulo D& #65533; fOdorico
2010-01-01
Vegetation water stress plays an important role in the movement of water through the soil�]plant�]atmosphere continuum. However, the effects of water stress on evapotranspiration (ET) and other hydrological processes at the watershed scale remain poorly understood due in part to spatially and temporally heterogeneous conditions within the...
Is brood parasitism related to host nestling diet and nutrition?
Zachary S. Ladin; Vincent D' Amico; Deb P. Jaisi; W. Gregory Shriver
2015-01-01
Food and nutrient limitation can have negative effects on survival, fecundity, and lifetime fitness of individuals, which can ultimately limit populations. Changes in trophic dynamics and diet patterns, affected by anthropogenic environmental and landscape change, are poorly understood yet may play an important role in population regulation. We determined diets of Wood...
USDA-ARS?s Scientific Manuscript database
To date, some biological activities have been confirmed as different named peptides, however, most FXPRLamide peptides are still poorly understood although these peptides are found in all insects. So, the study of receptors for these peptides is particularly important. Receptors of FXPRLamide peptid...
Principles of Cancer Screening.
Pinsky, Paul F
2015-10-01
Cancer screening has long been an important component of the struggle to reduce the burden of morbidity and mortality from cancer. Notwithstanding this history, many aspects of cancer screening remain poorly understood. This article presents a summary of basic principles of cancer screening that are relevant for researchers, clinicians, and public health officials alike. Published by Elsevier Inc.
Children's Ideas of Animals' Internal Structures
ERIC Educational Resources Information Center
Prokop, Pavol; Prokop, Matej; Tunnicliffe, Sue Dale; Diran, Carla
2007-01-01
Children's understanding about animal internal structure can be affected by several factors which are poorly understood by teachers. We conducted a large sample study (n=702) of children aged 6-16 years (Grades 1-9) examining children's responses to animals of various size, species and dimensions (2D and 3D objects), and exploring factors which…
Depressive Symptoms and Parenting Competence: An Analysis of 13 Regulatory Processes
ERIC Educational Resources Information Center
Dix, Theodore; Meunier, Leah N.
2009-01-01
Mechanisms that lead depressive symptoms to undermine parenting are poorly understood. This review examines cognitive, affective, and motivational processes thought to be responsible for the impact of depressive symptoms on parenting. We present a five-step, action-control model and review 152 studies relevant to 13 regulatory processes. Evidence…
How Does Creating a Concept Map Affect Item-Specific Encoding?
ERIC Educational Resources Information Center
Grimaldi, Phillip J.; Poston, Laurel; Karpicke, Jeffrey D.
2015-01-01
Concept mapping has become a popular learning tool. However, the processes underlying the task are poorly understood. In the present study, we examined the effect of creating a concept map on the processing of item-specific information. In 2 experiments, subjects learned categorized or ad hoc word lists by making pleasantness ratings, sorting…
Andrew MacDougall
2002-01-01
Garry oak (Quercus garryana) meadows of the Pacific Northwest are heavily invaded but the dynamics surrounding this ecosystem transformation are poorly understood. Of particular uncertainty is the role of the invasive species in structuring the community, and the potential stability of this invasive-dominated system when disturbed. Clarifying such...
The role of mites in insect-fungus associations
R. W. Hofstetter; J. C. Moser
2014-01-01
The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on...
Higher Learning, Greater Good: The Private and Social Benefits of Higher Education
ERIC Educational Resources Information Center
McMahon, Walter W.
2009-01-01
A college education has long been acknowledged as essential for both personal success and economic growth. But the measurable value of its nonmonetary benefits has until now been poorly understood. Walter W. McMahon, a leading education economist, carefully describes these benefits and suggests that higher education accrues significant social and…
Genetic Influences on Mechanically-Assessed Activity Level in Children
ERIC Educational Resources Information Center
Wood, Alexis C.; Saudino, Kimberly J.; Rogers, Hannah; Asherson, Philip; Kuntsi, Jonna
2007-01-01
Background: Activity level is an important component of children's temperament, as well as being part of the core symptom domain of hyperactivity-impulsivity within attention deficit hyperactivity disorder (ADHD). Yet it is poorly understood, due partly to limitations on parent and teacher ratings, which are typically used as measurements of these…
Differential Engagement of Brain Regions within a "Core" Network during Scene Construction
ERIC Educational Resources Information Center
Summerfield, Jennifer J.; Hassabis, Demis; Maguire, Eleanor A.
2010-01-01
Reliving past events and imagining potential future events engages a well-established "core" network of brain areas. How the brain constructs, or reconstructs, these experiences or scenes has been debated extensively in the literature, but remains poorly understood. Here we designed a novel task to investigate this (re)constructive process by…
A 2.5-D Representation of the Human Hand
ERIC Educational Resources Information Center
Longo, Matthew R.; Haggard, Patrick
2012-01-01
Primary somatosensory maps in the brain represent the body as a discontinuous, fragmented set of two-dimensional (2-D) skin regions. We nevertheless experience our body as a coherent three-dimensional (3-D) volumetric object. The links between these different aspects of body representation, however, remain poorly understood. Perceiving the body's…
Spleen size is an indirect indicator of rainbow trout bacterial cold water disease resistance
USDA-ARS?s Scientific Manuscript database
The contribution of the spleen to anti-bacterial immunity in lower vertebrates is poorly understood. The spleen first appears as a recognizable organ in shark and bony fish lineages while factors influencing its size and functions in lower vertebrates have received little attention. We have previou...
"Argument!" Helping Students Understand What Essay Writing Is About
ERIC Educational Resources Information Center
Wingate, Ursula
2012-01-01
Argumentation is a key requirement of the essay, which is the most common genre that students have to write. However, how argumentation is realised in disciplinary writing is often poorly understood by academic tutors, and therefore not adequately taught to students. This paper presents research into undergraduate students' concepts of argument…
Competition amplifies drought stress in forests across broad climatic and compositional gradients
Kelly E. Gleason; John B. Bradford; Alessandra Bottero; Anthony W. D' Amato; Shawn Fraver; Brian J. Palik; Michael A. Battaglia; Louis Iverson; Laura Kenefic; Christel C. Kern
2017-01-01
Forests around the world are experiencing increasingly severe droughts and elevated competitive intensity due to increased tree density. However, the influence of interactions between drought and competition on forest growth remains poorly understood. Using a unique dataset of stand-scale dendrochronology sampled from 6405 trees, we quantified how annual growth of...
A Truth that's Told with Bad Intent: An ERP Study of Deception
ERIC Educational Resources Information Center
Carrion, Ricardo E.; Keenan, Julian P.; Sebanz, Natalie
2010-01-01
Human social cognition critically relies on the ability to deceive others. However, the cognitive and neural underpinnings of deception are still poorly understood. Why does lying place increased demands on cognitive control? The present study investigated whether cognitive control processes during deception are recruited due to the need to…
USDA-ARS?s Scientific Manuscript database
Leptospirosis is a zoonotic infection of global importance, yet its population dynamics remain poorly understood. We present the first empirically-motivated study of the dynamics of leptospirosis, drawing on a unique 24-year time series of disease in California sea lions (CSLs). Since the early 19...
ERIC Educational Resources Information Center
Kochanska, Grazyna; Barry, Robin A.; Stellern, Sarah A.; O'Bleness, Jessica J.
2009-01-01
This multimethod study of 101 mothers, fathers, and children elucidates poorly understood role of children's attachment security as "moderating" a common maladaptive trajectory: from parental power assertion, to child resentful opposition, to child antisocial conduct. Children's security was assessed at 15 months, parents' power assertion observed…
Soil microbial responses to elevated CO2 and O3 in a nitrogen-aggrading agroecosystem
USDA-ARS?s Scientific Manuscript database
Despite decades of study, the underlying mechanisms by which soil microbes respond to rising atmospheric CO2 and ozone remain poorly understood. A prevailing hypothesis, which states that changes in C availability induced by elevated CO2 and ozone drive alterations in soil microbes and the processe...
USDA-ARS?s Scientific Manuscript database
Microsporidia constitute the most common black fl y pathogens, although the species’ diversity, seasonal occurrence and transmission mechanisms remain poorly understood. Infections by this agent are often chronic and non-lethal, but they can cause reduced fecundity and decreased longevity. The objec...
The AMPK-related kinase SNARK regulates muscle mass and myocyte survival
USDA-ARS?s Scientific Manuscript database
The maintenance of skeletal muscle mass is critical for sustaining health; however, the mechanisms responsible for muscle loss with aging and chronic diseases, such as diabetes and obesity, are poorly understood. We found that expression of a member of the AMPK-related kinase family, the SNF1-AMPK-r...
ERIC Educational Resources Information Center
Cleaver, Shaun; Ouellette-Kuntz, Helene; Hunter, Duncan
2008-01-01
As the population ages, mobility limitations are associated with increased mortality and negative health-related states both in the general population and among people with intellectual disabilities. The influence of mobility limitations upon the lives and lifestyles of people with intellectual disabilities remains poorly understood. Specifically,…
Engineering in Children's Fiction--Not a Good Story?
ERIC Educational Resources Information Center
Holbrook, Allyson; Panozza, Lisa; Prieto, Elena
2009-01-01
Responding to concerns that engineering is a poorly understood occupation and that young people are exposed to stereotyped images of scientists and engineers at an early age, this investigation sought to identify how science and engineering is portrayed in contemporary junior fiction (ages 8-12) and to what extent. An examination of 4,800 junior…
Insect-mediated nitrogen dynamics in decomposing wood
Michael D. Ulyshen
2015-01-01
1.Wood decomposition is characterised by complex and poorly understood nitrogen (N) dynamics with unclear implications for forest nutrient cycling and productivity.Wood-dwelling microbes have developed unique strategies for coping with the N limitations imposed by their substrate, including the translocation of N into wood by cord-forming fungi and the fixation of...
Observations and analysis of organic aerosol evolution in some prescribed fire smoke plumes
A. A. May; T. Lee; G. R. McMeeking; S. Akagi; A. P. Sullivan; S. Urbanski; R. J. Yokelson; S. M. Kreidenweis
2015-01-01
Open biomass burning is a significant source of primary air pollutants such as particulate matter (PM) and non-methane organic gases (NMOG). However, the physical and chemical atmospheric processing of these emissions during transport is poorly understood. Atmospheric transformations of biomass burning emissions have been investigated in environmental chambers, but...
Darren A. Miller; Ronald E. Thill; M. Anthony Melchiors; T. Bently Wigley; Philip A. Tappe
2004-01-01
Streamside management zones (SMZs), composed primarily of hardwoods in the southeastern United States, provide habitat diversity within intensively managed pine (Pinus spp.) plantations. However, effects of SMZ width and adjacent plantation structure on riparian wildlife communities are poorly understood. Therefore, during 1990-1995, we examined small mammal...
USDA-ARS?s Scientific Manuscript database
Carbon use by microorganisms in the rhizosphere microbiome has been linked to plant pathogen suppression and increased mineralization of soil nutrients for plant uptake, however factors that influence carbon use traits are poorly understood for most microbial groups. This work characterized the rela...
Increasing Conceptual Understanding of Glycolysis & the Krebs Cycle Using Role-Play
ERIC Educational Resources Information Center
Ross, Pauline M.; Tronson, Deidre A.; Ritchie, Raymond J.
2008-01-01
Cellular respiration and metabolism are topics that are reportedly poorly understood by students and judged to be difficult by many teachers. Although these topics may not be required learning areas in some high school biology curricula, a grasp of fundamental concepts of cellular metabolic processes is advantageous for students undertaking (or…
Matthew E. Craig; Jennifer M. Fraterrigo
2017-01-01
Many invasive plant species show high rates of nutrient acquisition relative to their competitors. Yet the mechanisms underlying this phenomenon, and its implications for ecosystem functioning, are poorly understood, particularly in nutrient-limited systems. Here, we test the hypothesis that an invasive plant species (Microstegium vimineum...
Etiology of Strokes in Children with Sickle Cell Anemia
ERIC Educational Resources Information Center
DeBaun, Michael R.; Derdeyn, Colin P.; McKinstry, Robert C., III
2006-01-01
The most devastating complication of sickle cell anemia is cerebral infarction, affecting [approximately]30% of all individuals with sickle cell anemia. Despite being one of the most common causes of stroke in infants and children, the mechanism of cerebral infarction in this population has not been extensively studied and is poorly understood.…
Does the Left Inferior Longitudinal Fasciculus Play a Role in Language? A Brain Stimulation Study
ERIC Educational Resources Information Center
Mandonnet, Emmanuel; Nouet, Aurelien; Gatignol, Peggy; Capelle, Laurent; Duffau, Hugues
2007-01-01
Although advances in diffusion tensor imaging have enabled us to better study the anatomy of the inferior longitudinal fasciculus (ILF), its function remains poorly understood. Recently, it was suggested that the subcortical network subserving the language semantics could be constituted, in parallel with the inferior occipitofrontal fasciculus, by…
David W. P. Manning; Amy D. Rosemond; Vladislav Gulis; Jonathan P. Benstead; John S. Kominoski; John C. Maerz
2016-01-01
Nutrient enrichment of detritus-based streams increases detrital resource quality for consumers and stimulates breakdown rates of particulate organic carbon (C). The relative importance of dissolved inorganic nitrogen (N) vs. phosphorus (P) for detrital quality and their effects on microbial- vs. detritivore-mediated detrital breakdown are poorly understood....
Probing crystallinity of never-dried wood cellulose with Raman spectroscopy
Umesh P. Agarwal; Sally A. Ralph; Richard S. Reiner; Carlos Baez
2016-01-01
The structure of wood cell wall cellulose in its native state remains poorly understood, limiting the progress of research and development in numerous areas, including plant science, biofuels, and nanocellulose based materials. It is generally believed that cellulose in cell wall microfibrils has both crystalline and amorphous regions. However, there is evidence that...
Consequences of Contextual Factors on Clinical Reasoning in Resident Physicians
ERIC Educational Resources Information Center
McBee, Elexis; Ratcliffe, Temple; Picho, Katherine; Artino, Anthony R., Jr.; Schuwirth, Lambert; Kelly, William; Masel, Jennifer; van der Vleuten, Cees; Durning, Steven J.
2015-01-01
Context specificity and the impact that contextual factors have on the complex process of clinical reasoning is poorly understood. Using situated cognition as the theoretical framework, our aim was to evaluate the verbalized clinical reasoning processes of resident physicians in order to describe what impact the presence of contextual factors have…
Substance Use and Fighting among Male and Female High School Youths: A Brief Report
ERIC Educational Resources Information Center
Noffsinger, Sandra; Clements-Nolle, Kristen; Bacon, Robinette; Lee, William; Albers, Eric; Yang, Wei
2012-01-01
While previous studies have investigated the relationship between substance use and violent behaviors among youths, the individual influence of specific drugs among males and females is poorly understood. Using the Nevada 2005 Youth Risk Behavior Surveillance (YRBS) Survey (N = 1,556), weighted logistic regression was used to assess the…
Genetically Diverse Coronaviruses in Wild Bird Populations of Northern England
Savage, Carol; Naylor, Clive; Bennett, Malcolm; Chantrey, Julian; Jones, Richard
2009-01-01
Infectious bronchitis virus (IBV) causes a costly respiratory viral disease of chickens. The role of wild birds in the epidemiology of IBV is poorly understood. We detected diverse coronaviruses by PCR in wildfowl and wading birds in England. Sequence analysis showed some viruses to be related to IBV. PMID:19624927
Dentate Gyrus Is Necessary for Disambiguating Similar Object-Place Representations
ERIC Educational Resources Information Center
Lee, Inah; Solivan, Frances
2010-01-01
Objects are often remembered with their locations, which is an important aspect of event memory. Despite the well-known involvement of the hippocampus in event memory, detailed intrahippocampal mechanisms are poorly understood. In particular, no experimental evidence has been provided in support of the role of the dentate gyrus (DG) in…
The effects of anthropogenic contaminants on indigenous Gulf of Mexico, near-coastal plant communities are poorly understood despite the declining number of seagrass communities and wetland emergent species. This study focuses on the third phase of a multi-year study designed to...
The Escalating Incidence of Suicide among African Americans: Implications for Counselors
ERIC Educational Resources Information Center
Day-Vines, Norma L.
2007-01-01
Suicide rates have soared among African Americans within the past 2 decades. Curiously, this fact remains poorly understood within and outside the African American community. This article includes a review of M. Compton, N. Thompson, and N. Kaslow's (2005) study, recently published in "Social Psychiatry" and "Psychiatric Epidemiology", and…
ERIC Educational Resources Information Center
Dignam, Jade; Copland, David; O'Brien, Kate; Burfein, Penni; Khan, Asaduzzaman; Rodriguez, Amy D.
2017-01-01
Purpose: The relationship between cognitive abilities and aphasia rehabilitation outcomes is complex and remains poorly understood. This study investigated the influence of language and cognitive abilities on anomia therapy outcomes in adults with aphasia. Method: Thirty-four adults with chronic aphasia participated in Aphasia Language Impairment…
Timothy B. Harrington; Christa M. Dagley; M. Boyd Edwards
2002-01-01
Although overstory trees limit the abundance and species richness of herbaceous vegetation in longleaf pine (Pinus palustris Mill.) plantations, the responsible mechanisms are poorly understood because of confounding among limiting factors. In fall 1998, research was initiated to determine the separate effects of above- and belowground competition...
ERIC Educational Resources Information Center
Hedley, Darren; Uljarevic, Mirko; Cameron, Lauren; Halder, Santoshi; Richdale, Amanda; Dissanayake, Cheryl
2017-01-01
Individuals with autism spectrum disorder face significant challenges entering the workforce; yet research in this area is limited and the issues are poorly understood. In this systematic review, empirical peer-reviewed studies on employment programmes, interventions and employment-related outcomes in individuals with autism spectrum disorder over…
Obesity-Related Hormones in Low-Income Preschool-Age Children: Implications for School Readiness
ERIC Educational Resources Information Center
Miller, Alison L.; Lumeng, Carey N.; Delproposto, Jennifer; Florek, Brian; Wendorf, Kristin; Lumeng, Julie C.
2013-01-01
Mechanisms underlying socioeconomic disparities in school readiness and health outcomes, particularly obesity, among preschool-aged children are complex and poorly understood. Obesity can induce changes in proteins in the circulation that contribute to the negative impact of obesity on health; such changes may relate to cognitive and emotion…
Approaches to Measuring and Understanding Employer Training Expenditure
ERIC Educational Resources Information Center
Smith, Andrew; Burke, Gerald; Long, Michael; Dumbrell, Tom
2008-01-01
While it is recognised that employers invest a substantial amount of money and time in training, the exact nature and amount of this investment is poorly measured and understood. This project set out to supplement the available data, which have many limitations, with more detailed data for selected industries. However, it became quickly apparent…
What Can ADHD without Comorbidity Teach Us about Comorbidity?
ERIC Educational Resources Information Center
Takeda, Toshinobu; Ambrosini, Paul J.; deBerardinis, Rachel; Elia, Josephine
2012-01-01
Neuropsychiatric comorbidity in ADHD is frequent, impairing and poorly understood. In this report, characteristics of comorbid and comorbid-free ADHD subjects are investigated in an attempt to identify differences that could potentially advance our understanding of risk factors. In a clinically-referred ADHD cohort of 449 youths (ages 6-18), age,…
Characteristics of Social Smoking among College Students
ERIC Educational Resources Information Center
Waters, Kimberly; Harris, Kari; Hall, Sandra; Nazir, Niaman; Waigandt, Alex
2006-01-01
Social smoking is a newly identified phenomenon in the young adult population that is poorly understood. We investigated differences in social smoking (smoking most commonly while partying or socializing) and other smoking within a convenience sample of college smokers (n = 351) from a large midwestern university. Results revealed that 70% of 351…
USDA-ARS?s Scientific Manuscript database
Premise of the Research: Jackfruit (Artocarpus heterophyllus, Moraceae) is an emerging but underutilized crop whose pollination is poorly understood. We present a multidimensional investigation of the reproductive biology and chemical ecology of jackfruit and a putative pollinator, Clinodiplosis ult...
ERIC Educational Resources Information Center
Cosner, Shelby
2012-01-01
Research suggests that school leaders play an important role in cultivating and developing collaborative data practices by teachers. Although diagnosis and intervention are critical facets of leaders' work to support collaborative data practice development, this work remains poorly understood. Missing from data-use literature is more explicit and…
ERIC Educational Resources Information Center
Ardiel, Evan L.; Giles, Andrew C.; Yu, Alex J.; Lindsay, Theodore H.; Lockery, Shawn R.; Rankin, Catharine H.
2016-01-01
Habituation is a highly conserved phenomenon that remains poorly understood at the molecular level. Invertebrate model systems, like "Caenorhabditis elegans," can be a powerful tool for investigating this fundamental process. Here we established a high-throughput learning assay that used real-time computer vision software for behavioral…
Matthew D. Powers; Kurt S. Pregitzer; Brian J. Palik; Christopher R. Webster
2011-01-01
Variable retention harvesting (VRH) is promoted for enhancing biodiversity and ecosystem processes in managed forests, but regeneration responses to the complex stand structures that result from VRH are poorly understood. We analyzed foliar stable carbon isotope ratios (δ13C), oxygen isotope ratios (δ18O...
Improving ITS sequence data for identification of plant pathogenic fungi
R. Henrik Nilsson; Kevin D. Hyde; Julia Pawłowska; Martin Ryberg; Leho Tedersoo; Anders Bjørnsgard Aas; Siti A. Alias; Artur Alves; Cajsa Lisa Anderson; Alexandre Antonelli; A. Elizabeth Arnold; Barbara Bahnmann; Mohammad Bahram; Johan Bengtsson-Palme; Anna Berlin; Sara Branco; Putarak Chomnunti; Asha Dissanayake; Rein Drenkhan; Hanna Friberg; Tobias Guldberg Frøslev; Bettina Halwachs; Martin Hartmann; Beatrice Henricot; Ruvishika Jayawardena; Ari Jumpponen; Håvard Kauserud; Sonja Koskela; Tomasz Kulik; Kare Liimatainen; Björn D. Lindahl; Daniel Lindner; Jian-Kui Liu; Sajeewa Maharachchikumbura; Dimuthu Manamgoda; Svante Martinsson; Maria Alice Neves; Tuula Niskanen; Stephan Nylinder; Olinto Liparini Pereira; Danilo Batista Pinho; Teresita M. Porter; Valentin Queloz; Taavi Riit; Marisol Sánchez-García; Filipe de Sousa; Emil Stefańczyk; Mariusz Tadych; Susumu Takamatsu; Qing Tian; Dhanushka Udayanga; Martin Unterseher; Zheng Wang; Saowanee Wikee; Jiye Yan; Ellen Larsson; Karl-Henrik Larsson; Urmas Kõljalg; Kessy Abarenkov
2014-01-01
Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours. These taxa often have complex and poorly understood life cycles, lack observable, discriminatory morphological characters, and may not be amenable to in vitro culturing. As a result, species identification is frequently difficult...
Influences of cyclic, high temperatures on juvenile channel catfish growth and feeding
USDA-ARS?s Scientific Manuscript database
Effects of high summer temperatures on channel catfish (Ictalurus punctatus) are poorly understood, particularly for thermal regimes that mimic pond aquaculture conditions. Therefore, this study examined the effects of three cycling upper-range temperature regimes (23-27ºC, 27-31ºC, and 31-35ºC) cha...
NASA Technical Reports Server (NTRS)
Greenwood, R. C.; Franchi, I. A.; Zolensky, M. E.; Buchanan, P. C.
2016-01-01
The process responsible for the mass independent oxygen isotope variation observed in Solar System materials remains poorly understood. While self-shielding of CO, either in the early solar nebula, or precursor molecular cloud, appears to be a viable mechanism, alternative models have also been proposed.
ERIC Educational Resources Information Center
Ehrlich, Katherine B.; Cassidy, Jude; Dykas, Matthew J.
2011-01-01
The issue of informant discrepancies about child and adolescent functioning is an important concern for clinicians, developmental psychologists, and others who must consider ways of handling discrepant reports of information, but reasons for discrepancies in reports have been poorly understood. Adolescent attachment and informant depressive…
Michael E. Akresh; David I. King; Robert T. Brooks
2015-01-01
Shrubland birds have experienced widespread declines in the eastern United States. Habitat for shrubland birds is typically dynamic, in which available habitat changes temporally and spatially in response to disturbance and succession. Despite widespread concerns among conservationists about shrubland birds, much is still poorly understood regarding fundamental...
Should I stay or should I go? Understanding the shapeshifting rainbow trout/steelhead
Geoff Koch; Gordon Reeves
2015-01-01
Steelhead are the sea-going form of Oncorhynchus mykiss. Rainbow trout,also O. mykiss, remain in freshwater. Each form, or life-history, can produce offspring of the other, but the mechanism for this and potential effects that climate change may have on the species are poorly understood.Forest...
The Populus homeobox gene ARBORKNOX2 regulates cell differentiation during secondary growth
Juan Du; Shawn D. Mansfield; Andrew T. Groover
2009-01-01
The stem cells of the vascular cambium divide to produce daughter cells, which in turn divide before undergoing differentiation during the radial growth of woody stems. The genetic regulation of these developmental events is poorly understood, however. We report here the cloning and functional characterization of a Populus class-I KNOX...
Aging-related susceptibility to environmental chemicals is poorly understood. Oxidative stress (OS) appears to play an important role in susceptibility and disease in old age. The objectives of this study, therefore, were to test whether OS is a potential toxicity pathway for tol...
Shishir P. S. Chundawat; Bryon S. Donohoe; Leonardo da Costa Sousa; Thomas Elder; Umesh P. Agarwal; Fachuang Lu; John Ralph; Michael E. Himmel; Venkatesh Balan; Bruce E. Dale
2011-01-01
Deconstruction of lignocellulosic plant cell walls to fermentable sugars by thermochemical and/or biological means is impeded by several poorly understood ultrastructural and chemical barriers. A promising thermochemical pretreatment called ammonia fiber expansion (AFEX) overcomes the native recalcitrance of cell walls through subtle morphological and physicochemical...
USDA-ARS?s Scientific Manuscript database
The mucosal surfaces of fish serve as the first-line of defense against the myriad of aquatic pathogens present in the aquatic environment. The immune repertoire functioning at these interfaces is still poorly understood. The skin, in particular, must process signals from several fronts, sensing and...
USDA-ARS?s Scientific Manuscript database
Cytokinin, auxin and gibberellin content in resting and wound-responding potato tuber are not clearly defined. Consequently, the coordination and possible networking of these classical hormones in the regulation of wound-healing processes are poorly understood. Using a well-defined tuber wound-hea...
Section 504 in American Public Schools: An Ongoing Response to Change
ERIC Educational Resources Information Center
Schraven, Jodie; Jolly, Jennifer L.
2010-01-01
This paper seeks to specifically focus on the evolution of civil rights case law and legislation as it pertains to educating students with disabilities, specifically the often implemented but poorly understood Section 504 provisions. The purpose of this paper is to examine historical influences that precipitated the implementation of Section 504…
Impact of six lignocellulosic biochars on C and N dynamics of two contrasting soils
USDA-ARS?s Scientific Manuscript database
Both soil and biochar properties have been shown to influence greenhouse gas emissions from biochar-amended soils, but the underlying mechanisms are poorly understood. Here we examine the effect of six lignocellulosic biochars produced from the pyrolysis of corn stover and wood feedstocks on CO2 and...
Cognitive Operations on Space and Their Impact on the Precision of Location Memory
ERIC Educational Resources Information Center
Lansdale, Mark; Humphries, Joyce; Flynn, Victoria
2013-01-01
Learning about object locations in space usually involves the summation of information from different experiences of that space and requires various cognitive operations to make this possible. These processes are poorly understood and, in the extreme, may not occur--leading to mutual exclusivity of memories (Baguley, Lansdale, Lines, & Parkin,…
Fluoxetine Restores Spatial Learning but Not Accelerated Forgetting in Mesial Temporal Lobe Epilepsy
ERIC Educational Resources Information Center
Barkas, Lisa; Redhead, Edward; Taylor, Matthew; Shtaya, Anan; Hamilton, Derek A.; Gray, William P.
2012-01-01
Learning and memory dysfunction is the most common neuropsychological effect of mesial temporal lobe epilepsy, and because the underlying neurobiology is poorly understood, there are no pharmacological strategies to help restore memory function in these patients. We have demonstrated impairments in the acquisition of an allocentric spatial task,…
ERIC Educational Resources Information Center
Morris, David S.
2016-01-01
Extracurricular activity participation (EAP) has been positively linked with increased academic achievement and college attendance. However, the mechanisms linking EAP to educational outcomes are poorly understood. Using the Education Longitudinal Study of 2002 (ELS), this study contributes to our understanding of the relationship between EAP and…
Migration is one of the most poorly understood components of a bird’s life cycle. For that reason, migratory stopover habitats are often not part of conservation planning and may be overlooked when planning new development projects. This project highlights and addresses an overl...
USDA-ARS?s Scientific Manuscript database
The mechanisms arthropods use to induce plant gall formation are poorly understood. However, there is growing evidence that effector proteins are involved. To examine this hypothesis, we sequenced the genome of the Hessian fly (Mayetiola destructor, M. des), an obligate plant parasitic gall midge an...
ERIC Educational Resources Information Center
Ryan, Julia; Ross, Samantha; Reyes, Rebecca; Kosmerly, Stacey; Rogers, Maria
2016-01-01
Despite the many studies that have documented the association between symptoms of ADHD and social difficulties in children and adolescents, few have examined this phenomenon in college students. In addition, the underlying factors contributing to such social difficulties are still poorly understood. We hypothesised that college students with…
ERIC Educational Resources Information Center
Balliet, Russell N.
2012-01-01
Understanding how geologists conduct fieldwork through analysis of problem solving has significant potential impact on field instruction methods. Recent progress has been made in this area but the problem solving behaviors displayed by geologists during fieldwork and the associated underlying cognition remains poorly understood. We present…
USDA-ARS?s Scientific Manuscript database
E. coli and enterococci are commonly used as pathogen indicators in surface water, however, the transport of these bacteria to drainage tiles from manure application fields and the correlation of these indicators to pathogens in this setting is poorly understood. Salmonella spp. is prevalent in poul...
Jill A. Zalesny; Ronald S., Jr. Zalesny; Adam H. Wiese; Bart Sexton; Richard B. Hall
2008-01-01
The response of Populus to irrigation sources containing elevated levels of sodium (Na+) and chloride (Cl-) is poorly understood. We irrigated eight Populus clones with fertilized well water (control) (N, P, K) or municipal solid waste landfill leachate weekly during 2005 and 2006 in...
Relative size and stand age determine Pinus banksiana mortality
Han Y. H. Chen; Songling Fu; Robert A. Monserud; Ian C. Gillies
2008-01-01
Tree mortality is a poorly understood process in the boreal forest. Whereas large disturbances reset succession by killing all or most trees, background tree mortality was hypothesized to be affected by competition, ageing, and stand composition. We tested these hypotheses on jack pine (Pinus banksiana Lamb.) mortality using data from long-term...
Abstract
Epidemiological studies suggest an association between ambient particulate matter and cardiopulmonary diseases in humans. The mechanisms underlying these health effects are poorly understood. To better understand the potential relationship between particulate-ma...
Fire history from three species on a central Appalachian ridgetop
Amy E. Hessl; Tom Saladyga; Thomas Schuler; Peter Clark; Joshua Wixom
2011-01-01
The impact of settlement era fires on Appalachian forests was substantial, but whether these fires affected the extent of fire-adapted ridgetop plant communities is poorly understood. Here we present fire history and stand structure of an Appalachian ridgetop (Pike Knob, West Virginia) based on fire scars from three species (Pinus pungens Lamb.,
ERIC Educational Resources Information Center
Olney, Nicholas T.; Goodkind, Madeleine S.; Lomen-Hoerth, Catherine; Whalen, Patrick K.; Williamson, Craig A.; Holley, Deborah E.; Verstaen, Alice; Brown, Laurel M.; Miller, Bruce L.; Kornak, John; Levenson, Robert W.; Rosen, Howard J.
2011-01-01
Pathological laughing and crying is a disorder of emotional expression seen in a number of neurological diseases. The aetiology is poorly understood, but clinical descriptions suggest a disorder of emotion regulation. The goals of this study were: (i) to characterize the subjective, behavioural and physiological emotional reactions that occur…
Tuomas Aakala; Shawn Fraver; Anthony W. D' Amato; Brian J. Palik
2013-01-01
Factors influencing tree growth in structurally complex forests remain poorly understood. Here we assessed the influence of competition on Pinus resinosa (n = 224) and Pinus strobus (n = 90) growth in four old-growth stands in Minnesota, using mixed effects models. A subset of trees, with...
ERIC Educational Resources Information Center
Bastedo, Michael N.; Bowman, Nicholas A.
2017-01-01
Low-socioeconomic status (SES) students are underrepresented at selective colleges, but the role that admissions offices play is poorly understood. Because admissions offices often have inconsistent information on high school contexts, we conducted a randomized controlled trial to determine whether providing detailed information on high school…
Is Pyrenophora semeniperda the cause of downy brome (Bromus tectorum) die-offs?
Owen W. Baughman; Susan E. Meyer
2013-01-01
Downy brome (cheatgrass) is a highly successful, exotic, winter annual invader in semi-arid western North America, forming near-monocultures across many landscapes. A frequent but poorly understood phenomenon in these heavily invaded areas is periodic 'die-off' or complete stand failure. The fungal pathogen Pyrenophora semeniperda is abundant in cheatgrass...
Stress Among Migrant and Seasonal Farmworkers in Rural Southeast North Carolina
ERIC Educational Resources Information Center
Kim-Godwin, Yeoun Soo; Bechtel, Gregory A.
2004-01-01
Although funding to enhance the delivery of health care among migrant farmworkers has primarily focused on urgent care issues within this population, the etiology of mental health risks and perceived stress is poorly understood. To identify the type and severity of stress perceived by migrant and seasonal farmworkers in rural southeast North…
Superior Temporal Activation in Response to Dynamic Audio-Visual Emotional Cues
ERIC Educational Resources Information Center
Robins, Diana L.; Hunyadi, Elinora; Schultz, Robert T.
2009-01-01
Perception of emotion is critical for successful social interaction, yet the neural mechanisms underlying the perception of dynamic, audio-visual emotional cues are poorly understood. Evidence from language and sensory paradigms suggests that the superior temporal sulcus and gyrus (STS/STG) play a key role in the integration of auditory and visual…
Parental Depression, Relationship Quality, and Nonresident Father Involvement with Their Infants
ERIC Educational Resources Information Center
Paulson, James F.; Dauber, Sarah E.; Leiferman, Jenn A.
2011-01-01
The role of depression in nonresident fathers' involvement with their infant children is poorly understood. A three-factor model of father involvement was evaluated, and its association with parental relationship quality and depressive symptoms in both parents were tested. Data on 569 families from the Early Childhood Longitudinal Study were used.…
USDA-ARS?s Scientific Manuscript database
The human pathogen Salmonella has shown a remarkable adaptability which allows these bacteria to thrive in a variety of environments and hosts. The manner in which these pathogens establish within a niche amidst the native microbiota remains poorly understood. Here, we aimed to uncover the mechanism...
USDA-ARS?s Scientific Manuscript database
Legumes and many nonleguminous plants enter symbiotic interactions with microbes, and it is poorly understood how host plants respond to promote beneficial, symbiotic microbial interactions while suppressing those that are deleterious or pathogenic. Trans-acting siRNAs (tasiRNAs) negatively regulate...
Air pollution is linked to central nervous system (CNS) disease, but the mechanisms responsible are poorly understood. Rats exposed to Diesel Exhaust (DE, 2.0,0.5, and 0 mg/m3) by inhalation over 4 weeks demonstrated elevated levels of whole brain IL-6 protein, nitrated proteins,...
USDA-ARS?s Scientific Manuscript database
Bud primordia of Picea abies, despite a frozen shoot, stay ice free down to -50 °C by a mechanism termed supercooling whose biophysical and biochemical requirements are poorly understood. Bud architecture was assessed by 3D-reconstruction, supercooling and freezing patterns by infrared video thermog...
The PH gene determines fruit acidity and contributes to the evolution of sweet melons
USDA-ARS?s Scientific Manuscript database
Acids are one of the three major components of fleshy fruit taste, together with sugars and volatile flavor compounds. However, the molecular-genetic control of acid accumulation in fruit is poorly understood and, to date, no genes responsible for acid accumulation in fleshy fruit have been function...
Seriously Considering Design in Educational Games
ERIC Educational Resources Information Center
Gaydos, Matthew
2015-01-01
Research suggests that well-designed games can be good for learning under the right conditions. How such games are designed remains poorly understood, as studies have focused more on "whether" games can produce learning than on how such games work or how they can be reliably developed. That is, though the design of a game is considered…
Non-native plants and wildlife in the Intermountain West
Andrea R. Litt; Dean E. Pearson
2013-01-01
Non-native plant invasions can change communities and ecosystems by altering the structure and composition of native vegetation. Changes in native plant communities caused by non-native plants can influence native wildlife species in diverse ways, but the outcomes and underlying mechanisms are poorly understood. Here, we review and synthesize current information for...
ERIC Educational Resources Information Center
Mehta, Mitul A.; Gore-Langton, Emma; Golembo, Nicole; Colvert, Emma; Williams, Steven C. R.; Sonuga-Barke, Edmund
2010-01-01
Severe deprivation in the first few years of life is associated with multiple difficulties in cognition and behavior. However, the brain basis for these difficulties is poorly understood. Structural and functional neuroimaging studies have implicated limbic system structures as dysfunctional, and one functional imaging study in a heterogeneous…
A review of ecological consequences of shifting the timing of burning tallgrass prairie
USDA-ARS?s Scientific Manuscript database
Prescribed burning is widely accepted as a critical management tool in the tallgrass prairie, however, the ecological effects of burning at different times of the season are poorly understood. In the Kansas Fleet Hills, timing of fire is an important management issue that carries socio-economic as w...
Environmental exposure and altered menstrual function
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keye, W.R. Jr.
The impact of environmental agents and occupational factors on hypothalamic and pituitary function and menstruation are poorly understood. To date, most research related to environment, occupation, and reproduction has focused on pregnancy outcome, not menstrual function. It is imperative, however, that menstrual function be considered as an outcome variable in the study of reproduction and occupation.
Modeling containment of large wildfires using generalized linear mixed-model analysis
Mark Finney; Isaac C. Grenfell; Charles W. McHugh
2009-01-01
Billions of dollars are spent annually in the United States to contain large wildland fires, but the factors contributing to suppression success remain poorly understood. We used a regression model (generalized linear mixed-model) to model containment probability of individual fires, assuming that containment was a repeated-measures problem (fixed effect) and...
QTL mapping and candidate gene analysis of telomere length control factors in maize (Zea mays L.)
USDA-ARS?s Scientific Manuscript database
Telomere length is under genetic control and important for essential telomere functions. Failure to regulate telomere length homeostasis contributes to cancers and aging-related diseases in animals, but the effects of telomere length defects in plants remains poorly understood. To learn more about t...
The health effects of long-term exposure to volatile organic compounds (VOCs) are poorly understood, due primarily to insufficient human exposure data and inconsistent animal models. To develop a rodent model of long-term exposure to VOCs, a sub-chronic inhalation study with mult...
Multi-decadal establishment for single-cohort Douglas-fir forests
James A. Freund; Jerry F. Franklin; Andrew J. Larson; James A. Lutz
2014-01-01
The rate at which trees regenerate following stand-replacing wildfire is an important but poorly understood process in the multi-century development of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) forests. Temporal patterns of Douglas-fir establishment reconstructed from old-growth forests (>450 year) have...
ERIC Educational Resources Information Center
Tort, Adriano B. L.; Komorowski, Robert; Kopell, Nancy; Eichenbaum, Howard
2011-01-01
The association of specific events with the context in which they occur is a fundamental feature of episodic memory. However, the underlying network mechanisms generating what-where associations are poorly understood. Recently we reported that some hippocampal principal neurons develop representations of specific events occurring in particular…
USDA-ARS?s Scientific Manuscript database
The effects of acute stressor exposure on proximal (growth hormone; GH) and distal (insulin-like growth factor-I; IGF-I and IGF-binding proteins) components of the somatotropic axis are poorly understood in finfish. We exposed rainbow trout (Oncorhynchus mykiss) to a 5-minute handling disturbance to...
Assessing Knowledge, Attitudes, and Behavior toward Charismatic Megafauna: The Case of Dolphins
ERIC Educational Resources Information Center
Barney, Erin C.; Mintzes, Joel J.; Yen, Chiung-Fen
2005-01-01
Using concept maps, a Kellert-type (S. R. Kellert, 1985) inventory, and self-report behavioral items, this cross-age study assessed public knowledge, attitudes, and behaviors toward bottlenose dolphins. Results suggest that this important megafaunal species is poorly understood by the public at large, and that negative "utilitarian" attitudes and…
ERIC Educational Resources Information Center
Gee, Gilbert C.; Pavalko, Eliza K.; Long, J. Scott
2007-01-01
Self-reported discrimination is linked to diminished well-being, but the processes generating these reports remain poorly understood. Employing the life course perspective, this paper examines the correspondence between expected age preferences for workers and perceived age discrimination among a nationally representative sample of 7,225 working…
Lateral, Not Medial, Prefrontal Cortex Contributes to Punishment and Aversive Instrumental Learning
ERIC Educational Resources Information Center
Jean-Richard-dit-Bressel , Philip; McNally, Gavan P.
2016-01-01
Aversive outcomes punish behaviors that cause their occurrence. The prefrontal cortex (PFC) has been implicated in punishment learning and behavior, although the exact roles for different PFC regions in instrumental aversive learning and decision-making remain poorly understood. Here, we assessed the role of the orbitofrontal (OFC), rostral…
ERIC Educational Resources Information Center
Knuepffer, C.; Murdoch, B. E.; Lloyd, D.; Lewis, F. M.; Hinchliffe, F. J.
2012-01-01
The immediate and long-term neural correlates of linguistic processing deficits reported following paediatric and adolescent traumatic brain injury (TBI) are poorly understood. Therefore, the current research investigated event-related potentials (ERPs) elicited during a semantic picture-word priming experiment in two groups of highly functioning…
USDA-ARS?s Scientific Manuscript database
Age-related macular degeneration (AMD) is a leading cause of visual impairment worldwide. Genetics and diet contribute to the relative risk for developing AMD, but their interactions are poorly understood. Genetic variations in Complement Factor H (CFH), and dietary glycemic index (GI) are major ris...
Assay dilution factors confound measures of total antioxidant capacity in polyphenol-rich juices
USDA-ARS?s Scientific Manuscript database
The extent to which sample dilution factor (DF) affects Total Antioxidant Capacity (TAC) values is poorly understood. Thus, we examined the impact of DF on the ORAC, FRAP, DPPH, and Total Phenols (TP) assays using pomegranate juice (PJ), grape juice (GJ), selected flavonoids, ascorbic acid, and ella...
Photomorphogenic responses to ultraviolet-B light.
Jenkins, Gareth I
2017-11-01
Exposure to ultraviolet B (UV-B) light regulates numerous aspects of plant metabolism, morphology and physiology through the differential expression of hundreds of genes. Photomorphogenic responses to UV-B are mediated by the photoreceptor UV RESISTANCE LOCUS8 (UVR8). Considerable progress has been made in understanding UVR8 action: the structural basis of photoreceptor function, how interaction with CONSTITUTIVELY PHOTOMORPHOGENIC 1 initiates signaling and how REPRESSOR OF UV-B PHOTOMORPHOGENESIS proteins negatively regulate UVR8 action. In addition, recent research shows that UVR8 mediates several responses through interaction with other signaling pathways, in particular auxin signaling. Nevertheless, many aspects of UVR8 action remain poorly understood. Most research to date has been undertaken with Arabidopsis, and it is important to explore the functions and regulation of UVR8 in diverse plant species. Furthermore, it is essential to understand how UVR8, and UV-B signaling in general, regulates processes under natural growth conditions. Ultraviolet B regulates the expression of many genes through UVR8-independent pathways, but the activity and importance of these pathways in plants growing in sunlight are poorly understood. © 2017 John Wiley & Sons Ltd.
Hunter, Karen E; Quick, Marsha L; Sadanandam, Anguraj; Hanahan, Douglas; Joyce, Johanna A
2013-01-01
Pancreatic neuroendocrine tumors (PanNETs) are a relatively rare but clinically challenging tumor type. In particular, high grade, poorly-differentiated PanNETs have the worst patient prognosis, and the underlying mechanisms of disease are poorly understood. In this study we have identified and characterized a previously undescribed class of poorly differentiated PanNETs in the RIP1-Tag2 mouse model. We found that while the majority of tumors in the RIP1-Tag2 model are well-differentiated insulinomas, a subset of tumors had lost multiple markers of beta-cell differentiation and were highly invasive, leading us to term them poorly differentiated invasive carcinomas (PDICs). In addition, we found that these tumors exhibited a high mitotic index, resembling poorly differentiated (PD)-PanNETs in human patients. Interestingly, we identified expression of Id1, an inhibitor of DNA binding gene, and a regulator of differentiation, specifically in PDIC tumor cells by histological analysis. The identification of PDICs in this mouse model provides a unique opportunity to study the pathology and molecular characteristics of PD-PanNETs.
Dust-forming molecules in VY Canis Majoris (and Betelgeuse)
NASA Astrophysics Data System (ADS)
Kamiński, T.; Gottlieb, C. A.; Schmidt, M. R.; Patel, N. A.; Young, K. H.; Menten, K. M.; Brünken, S.; Müller, H. S. P.; Winters, J. M.; McCarthy, M. C.
2013-05-01
The formation of inorganic dust in circumstellar environments of evolved stars is poorly understood. Spectra of molecules thought to be most important for the nucleation, i.e. AlO, TiO, and TiO2, have been recently detected in the red supergiant VY CMa. These molecules are effectively formed in VY CMa and the observations suggest that non-equilibrium chemistry must be involved in their formation and nucleation into dust. In addition to exploring the recent observations of VY CMa, we briefly discuss the possibility of detecting these molecules in the "dust-poor" circumstellar environment of Betelgeuse.
Scheel, Amy; Deal, Nick; St John, Natalie; Wells, Amy; Caruso, Maggie; Gilbert, Elizabeth R; Cline, Mark
2017-05-15
LPLRFamide is a member of the RFamide peptide family that elicits an anorexigenic effect when centrally injected in chicks although the mechanism mediating this response is poorly understood. Therefore, the purpose of this experiment was to elucidate the hypothalamic mechanism of short-term anorexia after central administration of LPLRFamide in chicks. In Experiment 1 chicks centrally injected with LPLRFamide decreased food intake at 15min but not 30min following administration compared to vehicle-injected chicks. For Experiment 2, c-Fos immunoreactivity was quantified in several appetite-associated hypothalamic nuclei and in LPLRF-injected chicks, compared to vehicle-injected chicks, there was an increase in the number of reactive cells in the magnocellular division of the paraventricular nucleus. Lastly in Experiment 3, real time-PCR was performed and hypothalamic proopiomelanocortin (POMC) mRNA abundance was increased in LPRLFamide-injected chicks compared to vehicle-injected chicks. Thus, following central injection of LPLRFamide there is activation of the paraventricular nucleus of the hypothalamus and increased expression of hypothalamic POMC mRNA in chicks. Copyright © 2016 Elsevier Inc. All rights reserved.
Carroll, J Matthew; Hovick, Torre J; Davis, Craig A; Elmore, Robert Dwayne; Fuhlendorf, Samuel D
2017-10-01
Disturbance is critical for the conservation of rangeland ecosystems worldwide and many of these systems are fire dependent. Although it is well established that restoring fire as an ecological process can lead to increased biodiversity in grasslands and shrublands, the underlying mechanisms driving community patterns are poorly understood for fauna in fire-prone landscapes. Much of this uncertainty stems from the paucity of studies that examine the effects of fire at scales relevant to organism life histories. We assessed the response of a non-migratory ground-dwelling bird to disturbance (i.e., prescribed fire) and environmental stochasticity over the course of a 4-yr period, which spanned years of historic drought and record rainfall. Specifically, we investigated the nesting ecology of Northern Bobwhite (Colinus virginianus; hereafter Bobwhite) to illuminate possible avenues by which individuals respond to dynamic landscape patterns during a critical reproductive stage (i.e., nesting) in a mixed-grass shrubland in western Oklahoma, USA. We found that Bobwhites exhibited extreme plasticity in nest substrate use among time since fire categories (TSF) and subsequently maintained high nest survival (e.g., 57-70%). Bobwhites were opportunistic in nest substrate use among TSF categories (i.e., 72% of nest sites in shrubs in 0-12 months post fire compared to 71% in herbaceous vegetation in >36 months post fire), yet nesting decisions were first filtered by similar structural components (i.e., vertical and horizontal cover) within the vicinity of nest sites regardless of TSF category. Despite being a non-migratory and comparatively less mobile ground-nesting bird species, Bobwhites adjusted to dynamic vegetation mosaics on a fire-prone landscape under stochastic climatic conditions that culminated in stable and high nest survival. Broadly, our findings provide a unique depiction of organism response strategies to fire at scales relevant to a critical life-stage, a topic that has been previously understudied and poorly understood. We also demonstrate how doing so can better inform conservation practices aimed at restoring fire regimes on grassland and shrubland landscapes. © 2017 by the Ecological Society of America.
Abundance patterns of the light neutron-capture elements in very and extremely metal-poor stars
NASA Astrophysics Data System (ADS)
Spite, F.; Spite, M.; Barbuy, B.; Bonifacio, P.; Caffau, E.; François, P.
2018-03-01
Aims: The abundance patterns of the neutron-capture elements in metal-poor stars provide a unique record of the nucleosynthesis products of the earlier massive primitive objects. Methods: We measured new abundances of so-called light neutron-capture of first peak elements using local thermodynamic equilibrium (LTE) 1D analysis; this analysis resulted in a sample of 11 very metal-poor stars, from [Fe/H] = -2.5 to [Fe/H] = -3.4, and one carbon-rich star, CS 22949-037 with [Fe/H] = -4.0. The abundances were compared to those observed in two classical metal-poor stars: the typical r-rich star CS 31082-001 ([Eu/Fe] > +1.0) and the r-poor star HD 122563 ([Eu/Fe] < 0.0), which are known to present a strong enrichment of the first peak neutron-capture elements relative to the second peak. Results: Within the first peak, the abundances are well correlated in analogy to the well-known correlation inside the abundances of the second-peak elements. In contrast, there is no correlation between any first peak element with any second peak element. We show that the scatter of the ratio of the first peak abundance over second peak abundance increases when the mean abundance of the second peak elements decreases from r-rich to r-poor stars. We found two new r-poor stars that are very similar to HD 122563. A third r-poor star, CS 22897-008, is even more extreme; this star shows the most extreme example of first peak elements enrichment to date. On the contrary, another r-poor star (BD-18 5550) has a pattern of first peak elements that is similar to the typical r-rich stars CS 31082-001, however this star has some Mo enrichment. Conclusions: The distribution of the neutron-capture elements in our very metal-poor stars can be understood as the combination of at least two mechanisms: one that enriches the forming stars cloud homogeneously through the main r-process and leads to an element pattern similar to the r-rich stars, such as CS 31082-001; and another that forms mainly lighter, first peak elements. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 165.N-0276(A), (PI R.Cayrel).
Makin-Byrd, Kerry; Cronkite, Ruth C; Timko, Christine
2011-07-01
Although abuse victimization and dual diagnosis are associated with poor functioning across numerous domains, their impact on attendance and involvement in mutual-help groups (MHGs) is not well understood. This study examined the impact of physical or sexual abuse victimization on MHG attendance and involvement and the influence of abuse on the association between MHG involvement and outcomes of abstinence and psychiatric health. Participants were 217 dually diagnosed men assessed at intake into mental health treatment and 6 months later. Compared with nonabused patients, sexually abused patients exhibited more substance use, psychiatric, and social problems at baseline and attended and were involved with MHGs more than nonabused patients at follow-up. Moreover, MHG involvement was most predictive of abstinence for sexually abused patients, as compared with nonabused and physically abused patients. Although dually diagnosed patients with abuse histories demonstrate more severe initial problems, they are likely to utilize MHGs, which may benefit efforts to achieve abstinence. Published by Elsevier Inc.
Bony cranial ornamentation linked to rapid evolution of gigantic theropod dinosaurs
NASA Astrophysics Data System (ADS)
Gates, Terry A.; Organ, Chris; Zanno, Lindsay E.
2016-09-01
Exaggerated cranial structures such as crests and horns, hereafter referred to collectively as ornaments, are pervasive across animal species. These structures perform vital roles in visual communication and physical interactions within and between species. Yet the origin and influence of ornamentation on speciation and ecology across macroevolutionary time scales remains poorly understood for virtually all animals. Here, we explore correlative evolution of osseous cranial ornaments with large body size in theropod dinosaurs using a phylogenetic comparative framework. We find that body size evolved directionally toward phyletic giantism an order of magnitude faster in theropod species possessing ornaments compared with unadorned lineages. In addition, we find a body mass threshold below which bony cranial ornaments do not originate. Maniraptoriform dinosaurs generally lack osseous cranial ornaments despite repeatedly crossing this body size threshold. Our study provides novel, quantitative support for a shift in selective pressures on socio-sexual display mechanisms in theropods coincident with the evolution of pennaceous feathers.
Assay Dilution Factors Confound Measures of Total Antioxidant Capacity in Polyphenol-Rich Juices
Bolling, Bradley W.; Chen, Ya-Yen; Kamil, Alison G.; Chen, C-Y. Oliver
2016-01-01
The extent to which sample dilution factor (DF) affects total antioxidant capacity (TAC) values is poorly understood. Thus, we examined the impact of DF on the ORAC, FRAP, DPPH, and total phenols (TP) assays using pomegranate juice (PJ), grape juice (GJ), selected flavonoids, ascorbic acid, and ellagic acid. For ORAC, GJ was comparable to PJ at DF 750, but at DF 2000, the ORAC value of GJ was 40% more than PJ. Increasing DF increased GJ and PJ, DPPH, TP, and FRAP values 11% and 14%, respectively. Increased test concentrations of quercetin and catechin resulted in 51% and 126% greater ORAC values, but decreased naringenin by 68%. Flavonoids, but not ellagic acid or ascorbic acid, may contribute to the dilution effect on the variation of final TAC values. Thus, reporting TAC or TP using a single DF may introduce uncertainty about the confidence of TAC assay values, especially when comparing different juices. These results underscore the importance of using compatible test standards for reporting TAC values. PMID:22251245