Factors influencing fire severity under moderate burning conditions in the Klamath Mountains, northern California, USA

Treesearch

Becky L. Estes; Eric E. Knapp; Carl N. Skinner; Jay D. Miller; Haiganoush K. Preisler

2017-01-01

Topography, weather, and fuels are known factors driving fire behavior, but the degree to which each contributes to the spatial pattern of fire severity under different conditions remains poorly understood. The variability in severity within the boundaries of the 2006 wildfires that burned in the Klamath Mountains, northern California, along with data on burn...

Juvenile Female Rats, but Not Male Rats, Show Renewal, Reinstatement, and Spontaneous Recovery Following Extinction of Conditioned Fear

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…

Body size and pubertal development explain ethnic differences in structural geometry at the femur in Asian, Hispanic and white early adolescent girls living in the US

USDA-ARS?s Scientific Manuscript database

Variation in structural geometry is present in adulthood, but when this variation arises and what influences this variation prior to adulthood remains poorly understood. Ethnicity is commonly the focus of research of skeletal integrity and appears to explain some of the variation in quantification o...

Dimensions of Perceived Racism and Self-Reported Health: Examination of Racial/Ethnic Differences and Potential Mediators

PubMed Central

Hausmann, Leslie R. M.; Jhalani, Juhee; Pencille, Melissa; Atencio-Bacayon, Jennifer; Kumar, Asha; Kwok, Jasmin; Ullah, Jahanara; Roth, Alan; Chen, Daniel; Crupi, Robert; Schwartz, Joseph

2016-01-01

Background Many details of the negative relationship between perceived racial/ethnic discrimination and health are poorly understood. Purpose The purpose of this study was to examine racial/ ethnic differences in the relationship between perceived discrimination and self-reported health, identify dimensions of discrimination that drive this relationship, and explore psychological mediators. Methods Asian, Black, and Latino(a) adults (N=734) completed measures of perceived racial/ethnic discrimination, self-reported health, depression, anxiety, and cynical hostility. Results The association between perceived discrimination and poor self-reported health was significant and did not differ across racial/ethnic subgroups. Race-related social exclusion and threat/harassment uniquely contributed to poor health for all groups. Depression, anxiety, and cynical hostility fully mediated the effect of social exclusion on health, but did not fully explain the effect of threat. Conclusions Our results suggest that noxious effects of race-related exclusion and threat transcend between-group differences in discriminatory experiences. The effects of race-related exclusion and threat on health, however, may operate through different mechanisms. PMID:21374099

Atmospheric Research at BNL

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

Atmospheric Research at BNL

ScienceCinema

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

Effects of nutrient additions on ecosystem carbon cycle in a Puerto Rican tropical wet forest

Treesearch

YIQING LI; MING XU; XIAOMING ZOU

2006-01-01

Wet tropical forests play a critical role in global ecosystem carbon (C) cycle, but C allocation and the response of different C pools to nutrient addition in these forests remain poorly understood. We measured soil organic carbon (SOC), litterfall, root biomass, microbial biomass and soil physical and chemical properties in a wet tropical forest from May 1996 to July...

Appraisal, Coping, and Social Support as Mediators of Well-Being in Black and White Family Caregivers of Patients with Alzheimer's Disease.

ERIC Educational Resources Information Center

Haley, William E.; And Others

1996-01-01

Family caregivers of patients with Alzheimer's disease (AD) commonly have high levels of psychological distress. Black caregivers often report less depression than white caregivers, but the process underlying this difference is poorly understood. With the use of a stress process model, 123 white and 74 black family caregivers of patients with AD…

Recent Alcohol, Tobacco, and Substance Use Variations between Rural and Urban Middle and High School Students

ERIC Educational Resources Information Center

Warren, Jacob C.; Smalley, K. Bryant; Barefoot, K. Nikki

2017-01-01

The use of addictive substances by adolescents is a major public health concern; however, rural versus urban variations are poorly understood. The purpose of the current study was to examine rural-urban differences in the prevalence of recent use of 11 substances in grades 6 through 12 in a statewide sample of students from the Georgia Student…

Structural adaptations to diverse fighting styles in sexually selected weapons

PubMed Central

McCullough, Erin L.; Tobalske, Bret W.; Emlen, Douglas J.

2014-01-01

The shapes of sexually selected weapons differ widely among species, but the drivers of this diversity remain poorly understood. Existing explanations suggest weapon shapes reflect structural adaptations to different fighting styles, yet explicit tests of this hypothesis are lacking. We constructed finite element models of the horns of different rhinoceros beetle species to test whether functional specializations for increased performance under species-specific fighting styles could have contributed to the diversification of weapon form. We find that horns are both stronger and stiffer in response to species-typical fighting loads and that they perform more poorly under atypical fighting loads, which suggests weapons are structurally adapted to meet the functional demands of fighting. Our research establishes a critical link between weapon form and function, revealing one way male–male competition can drive the diversification of animal weapons. PMID:25201949

Structural adaptations to diverse fighting styles in sexually selected weapons.

PubMed

McCullough, Erin L; Tobalske, Bret W; Emlen, Douglas J

2014-10-07

The shapes of sexually selected weapons differ widely among species, but the drivers of this diversity remain poorly understood. Existing explanations suggest weapon shapes reflect structural adaptations to different fighting styles, yet explicit tests of this hypothesis are lacking. We constructed finite element models of the horns of different rhinoceros beetle species to test whether functional specializations for increased performance under species-specific fighting styles could have contributed to the diversification of weapon form. We find that horns are both stronger and stiffer in response to species-typical fighting loads and that they perform more poorly under atypical fighting loads, which suggests weapons are structurally adapted to meet the functional demands of fighting. Our research establishes a critical link between weapon form and function, revealing one way male-male competition can drive the diversification of animal weapons.

MicroRNA-281 regulates the expression of ecdysone receptor (EcR) isoform B in the silkworm, Bombyx mori

USDA-ARS?s Scientific Manuscript database

Hundreds of Bombyx mori miRNAs had been identified in recent years, but their function in vivo remains poorly understood. The silkworm EcR gene (BmEcR) has three transcriptional isoforms, A, B1 and B2. Isoform sequences are different in the 3’UTR region of the gene, which is the case only in insects...

A trust-wide review of clinical nurse specialists' productivity.

PubMed

Balsdon, Helen; Wilkinson, Susan

2014-04-01

The contribution made by clinical nurse specialists (CNSs) to patient care needs to be understood fully to provide assurance of effective use of resources. However, CNS roles are often poorly understood and not easily articulated. Due to the diversity of these roles, robust reviews of performance and economic benefits can be regarded as time consuming and resource intense, and many organisations enlist external agencies to clarify the contribution to care made by their CNSs. This article gives an overview of a Cambridge University Hospitals NHS Foundation Trust internal review of CNS roles without the support of an external agency. The review provided assurance that this group of nurses is being used effectively and identified opportunities to use the role in different ways to increase effectiveness.

Sunday Liquor Laws and Crime

PubMed Central

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

Attend or defend? Sex differences in behavioral, autonomic, and respiratory response patterns to emotion-eliciting films.

PubMed

Wilhelm, Frank H; Rattel, Julina A; Wegerer, Melanie; Liedlgruber, Michael; Schweighofer, Simon; Kreibig, Sylvia D; Kolodyazhniy, Vitaliy; Blechert, Jens

2017-12-01

Sex differences in emotional reactivity have been studied primarily for negative but less so for positive stimuli; likewise, sex differences in the psychophysiological response-patterning during such stimuli are poorly understood. Thus, the present study examined sex differences in response to negative/positive and high/low arousing films (classified as threat-, loss-, achievement-, and recreation-related, vs. neutral films), while measuring 18 muscular, autonomic, and respiratory parameters. Sex differences emerged for all films, but were most prominent for threat-related films: Despite equivalent valence and arousal ratings, women displayed more facial-muscular and respiratory responding than men and pronounced sympathetic activation (preejection period, other cardiovascular and electrodermal measures), while men showed coactivated sympathetic/parasympathetic responding (including increased respiratory sinus arrhythmia). This indicates a prototypical threat-related defense response in women, while men showed a pattern of sustained orienting, which can be understood as a shift toward less threat proximity in the defense cascade model. Clinical implications are discussed within a socio-evolutionary framework. Copyright © 2017 Elsevier B.V. All rights reserved.

Systematic Review of Bilateral Independent Periodic Discharges Written for Topical Journal Subject on Periodic Discharges.

PubMed

Freund, Brin; Kaplan, Peter W

2018-05-01

Periodic discharges (PDs) are EEG patterns that may have important clinical and prognostic implications. There are different subtypes of PDs that are delineated by their location, and each type may have different meaning regarding prognosis and clinical associations. Bilateral independent PDs are a subtype that have not been analyzed recently and remain poorly understood. In this article, we systematically review the literature to better describe bilateral independent PDs regarding underlying neuropathology, neuroimaging, and neuroexamination correlates, seizure incidence, EEG characteristics, their comparison with other PD subtypes, and prognostic meaning.

Modelling and Holographic Visualization of Space Radiation-Induced DNA Damage

NASA Technical Reports Server (NTRS)

Plante, Ianik

2017-01-01

Space radiation is composed by a mixture of ions of different energies. Among these, heavy inos are of particular importance because their health effects are poorly understood. In. the recent years, a software named RITRACKS (Relativistic Ion Tracks) was developed to simulate the detailed radiation track structure, several DNA models and DNA damage. As the DNA structure is complex due to packing, it is difficult to the damage using a regular computer screen.

Novel Prostate Cancer Pathway Modeling using Boolean Implication

DTIC Science & Technology

2012-09-01

cause of cancer deaths in men. Diagnosis and pathogenesis of this disease is poorly understood. Prostate specific antigen (PSA) test is still the... specific database, I combined 14 different datasets (global prostate cancer database, total n=891) that are in Affymetrix U133A (n=456), U133A 2.0...immunohistochemistry and flow cytometry are limited by the availability of antigen - specific monoclonal antibodies and by the small number of parallel

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…

NASA Aims to Create First-Ever Space-Based Sodium Lidar to Study Poorly Understood Mesosphere

NASA Image and Video Library

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

Remote Sensing and Geologic Studies of Mare Australe: The North Australe Region

NASA Technical Reports Server (NTRS)

Lawrence, S. J.; Stopar, J. D.; Ostrach, L. R.; van der Bogert, C. H.; Hiesinger, H.; Jolliff, B. L.; Giguere, T. A.; Sato, H.; Robinson, M. S.

2017-01-01

A key goal of the Lunar Reconnaissance Orbiter (LRO) mission is to investigate volcanic processes at different temporal and physical scales, with one emphasis being the characterization of ancient (meaning, greater than 3.9 Ga) volcanic units. One such ancient volcanic terrain is Mare Australe, a loosely-circular collection of mare basalts centered at approximately 38.9 deg S, 93 deg E (Fig. 1). Mare Australe is a complex, extensive, and poorly understood volcanic region.

CYP2D6 predicted metabolizer status and safety in adult patients with attention-deficit hyperactivity disorder participating in a large placebo-controlled atomoxetine maintenance of response clinical trial.

PubMed

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.

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…

Factors Influencing the Sahelian Paradox at the Local Watershed Scale: Causal Inference Insights

NASA Astrophysics Data System (ADS)

Van Gordon, M.; Groenke, A.; Larsen, L.

2017-12-01

While the existence of paradoxical rainfall-runoff and rainfall-groundwater correlations are well established in the West African Sahel, the hydrologic mechanisms involved are poorly understood. In pursuit of mechanistic explanations, we perform a causal inference analysis on hydrologic variables in three watersheds in Benin and Niger. Using an ensemble of techniques, we compute the strength of relationships between observational soil moisture, runoff, precipitation, and temperature data at seasonal and event timescales. Performing analysis over a range of time lags allows dominant time scales to emerge from the relationships between variables. By determining the time scales of hydrologic connectivity over vertical and lateral space, we show differences in the importance of overland and subsurface flow over the course of the rainy season and between watersheds. While previous work on the paradoxical hydrologic behavior in the Sahel focuses on surface processes and infiltration, our results point toward the importance of subsurface flow to rainfall-runoff relationships in these watersheds. The hypotheses generated from our ensemble approach suggest that subsequent explorations of mechanistic hydrologic processes in the region include subsurface flow. Further, this work highlights how an ensemble approach to causal analysis can reveal nuanced relationships between variables even in poorly understood hydrologic systems.

Variation in the Gut Microbiota of Termites (Tsaitermes ampliceps) Against Different Diets.

PubMed

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.

Rapid and slow: Varying magma ascent rates as a mechanism for Vulcanian explosions

NASA Astrophysics Data System (ADS)

Cassidy, Mike; Cole, Paul. D.; Hicks, Kelby E.; Varley, Nick R.; Peters, Nial; Lerner, Allan H.

2015-06-01

Vulcanian explosions are one of the most common types of volcanic activity observed at silicic volcanoes. Magma ascent rates are often invoked as being the fundamental control on their explosivity, yet this factor is poorly constrained for low magnitude end-member Vulcanian explosions, which are particularly poorly understood, partly due to the rarity of ash samples and low gas fluxes. We describe ash generated by small Vulcanian explosions at Volcán de Colima in 2013, where we document for the first time marked differences in the vesicularity, crystal characteristics (volume fraction, size and shape) and glass compositions in juvenile material from discrete events. We interpret these variations as representing differing ascent styles and speeds of magma pulses within the conduit. Heterogeneous degassing during ascent leads to fast ascending, gas-rich magma pulses together with slow ascending gas-poor magma pulses within the same conduit. This inferred heterogeneity is complemented by SO2 flux data, which show transient episodes of both open and closed system degassing, indicating efficient shallow fracture sealing mechanisms, which allows for gas overpressure to generate small Vulcanian explosions.

The Road not Taken: Less Traveled Roads from the TGN to the Plasma Membrane

PubMed Central

Spang, Anne

2015-01-01

The trans-Golgi network functions in the distribution of cargo into different transport vesicles that are destined to endosomes, lysosomes and the plasma membrane. Over the years, it has become clear that more than one transport pathway promotes plasma membrane localization of proteins. In spite of the importance of temporal and spatial control of protein localization at the plasma membrane, the regulation of sorting into and the formation of different transport containers are still poorly understood. In this review different transport pathways, with a special emphasis on exomer-dependent transport, and concepts of regulation and sorting at the TGN are discussed. PMID:25764365

The Road not Taken: Less Traveled Roads from the TGN to the Plasma Membrane.

PubMed

Spang, Anne

2015-03-10

The trans-Golgi network functions in the distribution of cargo into different transport vesicles that are destined to endosomes, lysosomes and the plasma membrane. Over the years, it has become clear that more than one transport pathway promotes plasma membrane localization of proteins. In spite of the importance of temporal and spatial control of protein localization at the plasma membrane, the regulation of sorting into and the formation of different transport containers are still poorly understood. In this review different transport pathways, with a special emphasis on exomer-dependent transport, and concepts of regulation and sorting at the TGN are discussed.

Self-management of chronic low back pain: Four viewpoints from patients and healthcare providers.

PubMed

Stenner, Paul; Cross, Vinnette; McCrum, Carol; McGowan, Janet; Defever, Emmanuel; Lloyd, Phil; Poole, Robert; Moore, Ann P

2015-07-01

A move towards self-management is central to health strategy around chronic low back pain, but its concept and meaning for those involved are poorly understood. In the reported study, four distinct and shared viewpoints on self-management were identified among people with pain and healthcare providers using Q methodology. Each construes self-management in a distinctive manner and articulates a different vision of change. Identification of similarities and differences among the viewpoints holds potential for enhancing communication between patients and healthcare providers and for better understanding the complexities of self-management in practice.

Self-management of chronic low back pain: Four viewpoints from patients and healthcare providers

PubMed Central

Stenner, Paul; Cross, Vinnette; McCrum, Carol; McGowan, Janet; Defever, Emmanuel; Lloyd, Phil; Poole, Robert; Moore, Ann P

2015-01-01

A move towards self-management is central to health strategy around chronic low back pain, but its concept and meaning for those involved are poorly understood. In the reported study, four distinct and shared viewpoints on self-management were identified among people with pain and healthcare providers using Q methodology. Each construes self-management in a distinctive manner and articulates a different vision of change. Identification of similarities and differences among the viewpoints holds potential for enhancing communication between patients and healthcare providers and for better understanding the complexities of self-management in practice. PMID:28070378

DOE Office of Scientific and Technical Information (OSTI.GOV)

Badia-Martinez, Daniel; Peralta, Bibiana; Andres, German

Hepatitis C virus infects almost 170 million people per year but its assembly pathway, architecture and the structures of its envelope proteins are poorly understood. Using electron tomography of plastic-embedded sections of insect cells, we have visualized the morphogenesis of recombinant Hepatitis C virus-like particles. Our data provide a three-dimensional sketch of viral assembly at the endoplasmic reticulum showing different budding stages and contiguity of buds. This latter phenomenon could play an important role during the assembly of wt-HCV and explain the size-heterogeneity of its particles.

Isotopic signals of summer denitrification in a northern hardwood forested catchment

Treesearch

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…

The effects of perinatal testosterone exposure on the DNA methylome of the mouse brain are late-emerging

PubMed Central

2014-01-01

Background The biological basis for sex differences in brain function and disease susceptibility is poorly understood. Examining the role of gonadal hormones in brain sexual differentiation may provide important information about sex differences in neural health and development. Permanent masculinization of brain structure, function, and disease is induced by testosterone prenatally in males, but the possible mediation of these effects by long-term changes in the epigenome is poorly understood. Methods We investigated the organizational effects of testosterone on the DNA methylome and transcriptome in two sexually dimorphic forebrain regions—the bed nucleus of the stria terminalis/preoptic area and the striatum. To study the contribution of testosterone to both the establishment and persistence of sex differences in DNA methylation, we performed genome-wide surveys in male, female, and female mice given testosterone on the day of birth. Methylation was assessed during the perinatal window for testosterone's organizational effects and in adulthood. Results The short-term effect of testosterone exposure was relatively modest. However, in adult animals the number of genes whose methylation was altered had increased by 20-fold. Furthermore, we found that in adulthood, methylation at a substantial number of sexually dimorphic CpG sites was masculinized in response to neonatal testosterone exposure. Consistent with this, testosterone's effect on gene expression in the striatum was more apparent in adulthood. Conclusion Taken together, our data imply that the organizational effects of testosterone on the brain methylome and transcriptome are dramatic and late-emerging. Our findings offer important insights into the long-term molecular effects of early-life hormonal exposure. PMID:24976947

Waterborne disease-related risk perceptions in the Sonora River basin, Mexico.

PubMed

Morua, Agustin Robles; Halvorsen, Kathleen E; Mayer, Alex S

2011-05-01

Waterborne disease is estimated to cause about 10% of all diseases worldwide. However, related risk perceptions are not well understood, particularly in the developing world where waterborne disease is an enormous problem. We focus on understanding risk perceptions related to these issues in a region within northern Mexico. Our findings show how waterborne disease problems and solutions are understood in eight small communities along a highly contaminated river system. We found major differences in risk perceptions between health professionals, government officials, and lay citizens. Health professionals believed that a high level of human-waste-related risk existed within the region. Few officials and lay citizens shared this belief. In addition, few officials and lay citizens were aware of poor wastewater-management-related disease outbreaks and water contamination. Finally, aside from health professionals, a few interviewees understood the importance of basic hygiene and water treatment measures that could help to prevent disease. Our results add to the literature on environmentally-related risk perceptions in the developing world. We discuss recommendations for improving future human-wastewater-related risk communication within the region. © 2011 Society for Risk Analysis.

Individual Differences Reveal Correlates of Hidden Hearing Deficits

PubMed Central

Masud, Salwa; Mehraei, Golbarg; Verhulst, Sarah; Shinn-Cunningham, Barbara G.

2015-01-01

Clinical audiometry has long focused on determining the detection thresholds for pure tones, which depend on intact cochlear mechanics and hair cell function. Yet many listeners with normal hearing thresholds complain of communication difficulties, and the causes for such problems are not well understood. Here, we explore whether normal-hearing listeners exhibit such suprathreshold deficits, affecting the fidelity with which subcortical areas encode the temporal structure of clearly audible sound. Using an array of measures, we evaluated a cohort of young adults with thresholds in the normal range to assess both cochlear mechanical function and temporal coding of suprathreshold sounds. Listeners differed widely in both electrophysiological and behavioral measures of temporal coding fidelity. These measures correlated significantly with each other. Conversely, these differences were unrelated to the modest variation in otoacoustic emissions, cochlear tuning, or the residual differences in hearing threshold present in our cohort. Electroencephalography revealed that listeners with poor subcortical encoding had poor cortical sensitivity to changes in interaural time differences, which are critical for localizing sound sources and analyzing complex scenes. These listeners also performed poorly when asked to direct selective attention to one of two competing speech streams, a task that mimics the challenges of many everyday listening environments. Together with previous animal and computational models, our results suggest that hidden hearing deficits, likely originating at the level of the cochlear nerve, are part of “normal hearing.” PMID:25653371

Evolution of a sediment wave in an experimental channel

Treesearch

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

Treesearch

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)

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.

Functional heartburn: the stimulus, the pain, and the brain

PubMed Central

Fass, R; Tougas, G

2002-01-01

Functional heartburn is a common disorder and appears to be composed of several distinct subgroups. Identifying the different subgroups based on clinical history only is not achievable at present. The mechanisms responsible for pain, clinical characteristics, and the optimal therapeutic approach remain poorly understood. Response to potent antireflux treatment is relatively limited. Current and future treatment strategies for functional heartburn patients who have failed standard dose proton pump inhibitors (PPIs) include increased PPI dose in some, as well as addition of pain modulators in others. PMID:12427796

What does productivity really mean? Towards an integrative paradigm in the search for biodiversity-productivity relationships

Treesearch

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,...

Low serum omega-3 and omega-6 polyunsaturated fatty acids and other metabolites are associated with poor linear growth in young children from rural Malawi

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...

Subsurface metabolic potential on the Costa Rican Margin

NASA Astrophysics Data System (ADS)

Biddle, J.; Leon, Z. R.; Martino, A. J.; Bousses, K.; House, C. H.

2017-12-01

The distribution of archaea and bacteria and their associated metabolic abilities in the deep subseafloor are poorly understood. In order to explore this, we focused on samples from the Costa Rica margin IODP Expedition 334. The microbial community was analyzed via metagenomics in two different sites at multiple depths. At Site 1378, samples are from 2 meters below the sea floor (mbsf), 33 mbsf and 93 mbsf, and at Site 1379 from 22 mbsf to 45 mbsf. Whole community analysis of conserved gene markers in the metagenome show that the microbial community varies with depth, and drastically differs between the two geographically close sites. Thirty-two genomes were recovered from the metagenomic data with more than 30% completion. Archaea make 49% of all genomes recovered and over 90% of these recovered genomes belong to recently discovered and poorly characterized groups of Archaea. This study explored the relative dynamics of microbial communities in the deep biosphere and presents the metabolic potential of distinct subsurface biosphere archaeal groups.

Supporting Pakistani and Chinese families with young children: perspectives of mothers and health visitors.

PubMed

Hogg, R; de Kok, B; Netto, G; Hanley, J; Haycock-Stuart, E

2015-05-01

In the UK, public health nurses (health visitors) provide support and advice to families with young children, including those from minority ethnic communities. While the need for cultural sensitivity is being increasingly recognized, the factors which contribute to this sensitivity are poorly understood. The Pakistani and Chinese communities constitute the two largest minority ethnic groups in Scotland. This study explored Pakistani and Chinese women's experience of motherhood and of the health visiting service and public health nurses' experiences of working with Chinese and Pakistani mothers. Semi-structured individual interviews were carried out with 16 Pakistani and 15 Chinese mothers. Eight health visitors took part in two focus groups. The study was undertaken in an urban area of Scotland. Data were analysed thematically. Chinese and Pakistani mothers negotiate complex processes in order to ensure that their children maintain their own ethnic identity while fitting in with their peers in their adopted country. Health visitors were seen as supportive, although sometimes advice and information given was culturally inappropriate, and their role was often poorly understood. Health visitors were anxious to be sensitive to families' religious and cultural beliefs. Cultural sensitivity is an important factor in providing appropriate advice and help to Pakistani and Chinese families, and involves health visitors in considering views and practices on parenting which may differ across cultures, including their own. Family characteristics need to be understood on an individual basis, rather than making assumptions about clients' cultural norms and lifestyles. This is best achieved by exploring with mothers if they understand the advice and information they are being offered and also if it is appropriate to their cultural and religious beliefs. © 2014 John Wiley & Sons Ltd.

Deconstructing and Reconstructing Cognitive Performance in Sleep Deprivation

PubMed Central

Jackson, Melinda L.; Gunzelmann, Glenn; Whitney, Paul; Hinson, John M.; Belenky, Gregory; Rabat, Arnaud; Van Dongen, Hans P. A.

2012-01-01

Summary Mitigation of cognitive impairment due to sleep deprivation in operational settings is critical for safety and productivity. Achievements in this area are hampered by limited knowledge about the effects of sleep loss on actual job tasks. Sleep deprivation has different effects on different cognitive performance tasks, but the mechanisms behind this task-specificity are poorly understood. In this context it is important to recognize that cognitive performance is not a unitary process, but involves a number of component processes. There is emerging evidence that these component processes are differentially affected by sleep loss. Experiments have been conducted to decompose sleep-deprived performance into underlying cognitive processes using cognitive-behavioral, neuroimaging and cognitive modeling techniques. Furthermore, computational modeling in cognitive architectures has been employed to simulate sleep-deprived cognitive performance on the basis of the constituent cognitive processes. These efforts are beginning to enable quantitative prediction of the effects of sleep deprivation across different task contexts. This paper reviews a rapidly evolving area of research, and outlines a theoretical framework in which the effects of sleep loss on cognition may be understood from the deficits in the underlying neurobiology to the applied consequences in real-world job tasks. PMID:22884948

Deconstructing and reconstructing cognitive performance in sleep deprivation.

PubMed

Jackson, Melinda L; Gunzelmann, Glenn; Whitney, Paul; Hinson, John M; Belenky, Gregory; Rabat, Arnaud; Van Dongen, Hans P A

2013-06-01

Mitigation of cognitive impairment due to sleep deprivation in operational settings is critical for safety and productivity. Achievements in this area are hampered by limited knowledge about the effects of sleep loss on actual job tasks. Sleep deprivation has different effects on different cognitive performance tasks, but the mechanisms behind this task-specificity are poorly understood. In this context it is important to recognize that cognitive performance is not a unitary process, but involves a number of component processes. There is emerging evidence that these component processes are differentially affected by sleep loss. Experiments have been conducted to decompose sleep-deprived performance into underlying cognitive processes using cognitive-behavioral, neuroimaging and cognitive modeling techniques. Furthermore, computational modeling in cognitive architectures has been employed to simulate sleep-deprived cognitive performance on the basis of the constituent cognitive processes. These efforts are beginning to enable quantitative prediction of the effects of sleep deprivation across different task contexts. This paper reviews a rapidly evolving area of research, and outlines a theoretical framework in which the effects of sleep loss on cognition may be understood from the deficits in the underlying neurobiology to the applied consequences in real-world job tasks. Copyright © 2012 Elsevier Ltd. All rights reserved.

Digestive tract absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant

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

Musical Experience, Auditory Perception and Reading-Related Skills in Children

PubMed Central

Banai, Karen; Ahissar, Merav

2013-01-01

Background The relationships between auditory processing and reading-related skills remain poorly understood despite intensive research. Here we focus on the potential role of musical experience as a confounding factor. Specifically we ask whether the pattern of correlations between auditory and reading related skills differ between children with different amounts of musical experience. Methodology/Principal Findings Third grade children with various degrees of musical experience were tested on a battery of auditory processing and reading related tasks. Very poor auditory thresholds and poor memory skills were abundant only among children with no musical education. In this population, indices of auditory processing (frequency and interval discrimination thresholds) were significantly correlated with and accounted for up to 13% of the variance in reading related skills. Among children with more than one year of musical training, auditory processing indices were better, yet reading related skills were not correlated with them. A potential interpretation for the reduction in the correlations might be that auditory and reading-related skills improve at different rates as a function of musical training. Conclusions/Significance Participants’ previous musical training, which is typically ignored in studies assessing the relations between auditory and reading related skills, should be considered. Very poor auditory and memory skills are rare among children with even a short period of musical training, suggesting musical training could have an impact on both. The lack of correlation in the musically trained population suggests that a short period of musical training does not enhance reading related skills of individuals with within-normal auditory processing skills. Further studies are required to determine whether the associations between musical training, auditory processing and memory are indeed causal or whether children with poor auditory and memory skills are less likely to study music and if so, why this is the case. PMID:24086654

Individual differences reveal correlates of hidden hearing deficits.

PubMed

Bharadwaj, Hari M; Masud, Salwa; Mehraei, Golbarg; Verhulst, Sarah; Shinn-Cunningham, Barbara G

2015-02-04

Clinical audiometry has long focused on determining the detection thresholds for pure tones, which depend on intact cochlear mechanics and hair cell function. Yet many listeners with normal hearing thresholds complain of communication difficulties, and the causes for such problems are not well understood. Here, we explore whether normal-hearing listeners exhibit such suprathreshold deficits, affecting the fidelity with which subcortical areas encode the temporal structure of clearly audible sound. Using an array of measures, we evaluated a cohort of young adults with thresholds in the normal range to assess both cochlear mechanical function and temporal coding of suprathreshold sounds. Listeners differed widely in both electrophysiological and behavioral measures of temporal coding fidelity. These measures correlated significantly with each other. Conversely, these differences were unrelated to the modest variation in otoacoustic emissions, cochlear tuning, or the residual differences in hearing threshold present in our cohort. Electroencephalography revealed that listeners with poor subcortical encoding had poor cortical sensitivity to changes in interaural time differences, which are critical for localizing sound sources and analyzing complex scenes. These listeners also performed poorly when asked to direct selective attention to one of two competing speech streams, a task that mimics the challenges of many everyday listening environments. Together with previous animal and computational models, our results suggest that hidden hearing deficits, likely originating at the level of the cochlear nerve, are part of "normal hearing." Copyright © 2015 the authors 0270-6474/15/352161-12$15.00/0.

Linking Early Environmental Exposures to Adult Diseases

MedlinePlus

... 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 ...

Characteristic of root decomposition in a tropical rainforest in Sarawak, Malaysi

NASA Astrophysics Data System (ADS)

Ohashi, Mizue; Makita, Naoki; Katayam, Ayumi; Kume, Tomonori; Matsumoto, Kazuho; Khoon Kho, L.

2016-04-01

Woody roots play a significant role in forest carbon cycling, as up to 60 percent of tree photosynthetic production can be allocated to belowground. Root decay is one of the main processes of soil C dynamics and potentially relates to soil C sequestration. However, much less attention has been paid for root litter decomposition compared to the studies of leaf litter because roots are hidden from view. Previous studies have revealed that physico-chemical quality of roots, climate, and soil organisms affect root decomposition significantly. However, patterns and mechanisms of root decomposition are still poorly understood because of the high variability of root properties, field environment and potential decomposers. For example, root size would be a factor controlling decomposition rates, but general understanding of the difference between coarse and fine root decompositions is still lacking. Also, it is known that root decomposition is performed by soil animals, fungi and bacteria, but their relative importance is poorly understood. In this study, therefore, we aimed to characterize the root decomposition in a tropical rainforest in Sarawak, Malaysia, and clarify the impact of soil living organisms and root sizes on root litter decomposition. We buried soil cores with fine and coarse root litter bags in soil in Lambir Hills National Park. Three different types of soil cores that are covered by 1.5 cm plastic mesh, root-impermeable sheet (50um) and fungi-impermeable sheet (1um) were prepared. The soil cores were buried in February 2013 and collected 4 times, 134 days, 226 days, 786 days and 1151 days after the installation. We found that nearly 80 percent of the coarse root litter was decomposed after two years, whereas only 60 percent of the fine root litter was decomposed. Our results also showed significantly different ratio of decomposition between different cores, suggesting the different contribution of soil living organisms to decomposition process.

An inexpensive and portable drill rig for bedrock groundwater studies in headwater catchments

Treesearch

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...

Measurements of evaporation from a mine void lake and testing of modelling approaches

NASA Astrophysics Data System (ADS)

McJannet, David; Hawdon, Aaron; Van Niel, Tom; Boadle, Dave; Baker, Brett; Trefry, Mike; Rea, Iain

2017-12-01

Pit lakes often form in the void that remains after open cut mining operations cease. As pit lakes fill, hydrological and geochemical processes interact and these need to be understood for appropriate management actions to be implemented. Evaporation is important in the evolution of pit lakes as it acts to concentrate various constituents, controls water level and changes the thermal characteristics of the water body. Despite its importance, evaporation from pit lakes is poorly understood. To address this, we used an automated floating evaporation pan and undertook measurements at a pit lake over a 12 month period. We also developed a new procedure for correcting floating pan evaporation estimates to lake evaporation estimates based on surface temperature differences. Total annual evaporation was 2690 mm and reflected the strong radiation inputs, high temperatures and low humidity experienced in this region. Measurements were used to test the performance of evaporation estimates derived using both pan coefficient and aerodynamic modelling techniques. Daily and monthly evaporation estimates were poorly reproduced using pan coefficient techniques and their use is not recommended for such environments. Aerodynamic modelling was undertaken using a range of input datasets that may be available to those who manage pit lake systems. Excellent model performance was achieved using over-water or local over-land meteorological observations, particularly when the sheltering effects of the pit were considered. Model performance was reduced when off-site data were utilised and differences between local and off-site vapor pressure and wind speed were found to be the major cause.

Researchers Realize Major Breakthrough in Understanding Endometriosis

MedlinePlus

... 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 ...

Induction of Inhibitory Receptors on T Cells During Plasmodium vivax Malaria Impairs Cytokine Production

PubMed Central

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

Small vessel disease, neurovascular regulation and cognitive impairment: post-mortem studies reveal a complex relationship, still poorly understood.

PubMed

Love, Seth; Miners, J Scott

2017-07-15

The contribution of vascular disease to cognitive impairment is under-recognized and the pathogenesis is poorly understood. This information gap has multiple causes, including a lack of post-mortem validation of clinical diagnoses of vascular cognitive impairment (VCI) or vascular dementia (VaD), the exclusion of cases with concomitant neurodegenerative disease when diagnosing VCI/VaD, and a lack of standardization of neuropathological assessment protocols for vascular disease. Other contributors include a focus on end-stage destructive lesions to the exclusion of more subtle types of diffuse brain injury, on structural abnormalities of arteries and arterioles to the exclusion of non-structural abnormalities and capillary damage, and the use of post-mortem sampling strategies that are biased towards the identification of neurodegenerative pathologies. Recent studies have demonstrated the value of detailed neuropathology in characterizing vascular contributions to cognitive impairment (e.g. in diabetes), and highlight the importance of diffuse white matter changes, capillary damage and vasoregulatory abnormalities in VCI/VaD. The use of standardized, evidence-based post-mortem assessment protocols and the inclusion of biochemical as well as morphological methods in neuropathological studies should improve the accuracy of determination of the contribution of vascular disease to cognitive impairment and clarify the relative contribution of different pathogenic processes to the tissue damage. © 2017 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

The market of human organs: a window into a poorly understood global business.

PubMed

Surman, O S; Saidi, R; Purtilo, R; Simmerling, M; Ko, D; Burke, T F

2008-03-01

The global demand for human organs has set the stage for an exploding and poorly understood global business in human organs. Whenever there is demand for a product, the opportunity for business arises. The form that a business takes is dependent on a complex network of inputs and outputs, each affecting the others. Historically, the details of any specific market are drastically underestimated. Nowhere is this truer than in the market of human organs. The drivers, which propel the "goods" of human organs, form a flourishing business. Critical analysis is essential to understanding of the supply and demand sides and to determine the role of government in regulating the industry. Governmental groups have dismissed formation of a regulated market for organ sales. The concept is nonetheless a topic of active discussion, motivated by the suffering of patients in need of organs and exploitation of the victims of human trafficking. Ethical principles have been invoked on each side of the ensuing debate. Theory in the absence of sufficient data is shaky ground for enactment of new policy. The Aristotelian concept of "practical wisdom" and the pragmatism of William James illuminate the importance of scientific investigation as guide to policy formation. How will stakeholders benefit or lose? What impact might be anticipated in regard to organized medicine's social contract? What can we learn about cross-cultural differences and their effect on the global landscape?

Understanding asexual identity as a means to facilitate culturally competent care: A systematic literature review.

PubMed

Jones, Catriona; Hayter, Mark; Jomeen, Julie

2017-12-01

To provide a contemporary overview of asexuality and the implications this has for healthcare practice. Individuals belonging to sexual minority groups face many barriers in accessing appropriate health care. The term "sexual minority group" is usually used to refer to lesbian women, gay, bisexual and transgender individuals. Anecdotal and research evidence suggests that those who identify as asexual have similar poor experiences. Systematic review and qualitative analysis. This work uses a systematic review and qualitative analysis of the existing interview data from self-identified asexuals, to construct features of the asexual identity. The findings will help practitioners and health professionals develop an understanding of this poorly understood construct. Ultimately this work is aimed at facilitating culturally competent care in the context of asexuality. Qualitative analysis produced three themes, which can be used, not only to frame asexuality in a positive and normalising way, but also to provide greater understanding of asexuality, "romantic differences coupled with sexual indifference," "validation through engagement with asexual communities" and "a diversity of subasexual identities." Having some understanding of what it means to identify as asexual, and respecting the choices made by asexuals can markedly improve the experiences of those who embrace an asexual identity when engaging with health care. Anecdotal evidence, taken from one of the largest asexual online forums, suggests that a number of self-identified asexuals choose not to disclose their identity to healthcare professionals through fear of their asexual status being pathologised, problematised or judged. Given that asexuality is a poorly understood concept, this may be due to lack of understanding on behalf of healthcare providers. The review provides health professionals and practitioners working in clinical settings with some insights of the features of an asexual identity to facilitate culturally competent care. © 2017 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...

Sex differences in the reciprocal behaviour of children with autism.

PubMed

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.

Fine-scale landscape genetics of the American badger (Taxidea taxus): disentangling landscape effects and sampling artifacts in a poorly understood species

PubMed Central

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

Biodiversity and ecosystem function in species-poor communities: community structure and leaf litter breakdown in a Pacific island stream

Treesearch

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...

Structure of Ljungan virus provides insight into genome packaging of this picornavirus

NASA Astrophysics Data System (ADS)

Zhu, Ling; Wang, Xiangxi; Ren, Jingshan; Porta, Claudine; Wenham, Hannah; Ekström, Jens-Ola; Panjwani, Anusha; Knowles, Nick J.; Kotecha, Abhay; Siebert, C. Alistair; Lindberg, A. Michael; Fry, Elizabeth E.; Rao, Zihe; Tuthill, Tobias J.; Stuart, David I.

2015-10-01

Picornaviruses are responsible for a range of human and animal diseases, but how their RNA genome is packaged remains poorly understood. A particularly poorly studied group within this family are those that lack the internal coat protein, VP4. Here we report the atomic structure of one such virus, Ljungan virus, the type member of the genus Parechovirus B, which has been linked to diabetes and myocarditis in humans. The 3.78-Å resolution cryo-electron microscopy structure shows remarkable features, including an extended VP1 C terminus, forming a major protuberance on the outer surface of the virus, and a basic motif at the N terminus of VP3, binding to which orders some 12% of the viral genome. This apparently charge-driven RNA attachment suggests that this branch of the picornaviruses uses a different mechanism of genome encapsidation, perhaps explored early in the evolution of picornaviruses.

Coronary artery disease in Bangladesh: A review

PubMed Central

Islam, A.K.M. Monwarul; Majumder, A.A.S.

2013-01-01

Coronary artery disease (CAD) is an increasingly important medical and public health problem, and is the leading cause of mortality in Bangladesh. Like other South Asians, Bangladeshis are unduly prone to develop CAD, which is often premature in onset, follows a rapidly progressive course and angiographically more severe. The underlying pathophysiology is poorly understood. Genetic predisposition, high prevalence of metabolic syndrome and conventional risk factors play important role. Lifestyle related factors, including poor dietary habits, excess saturated and trans fat, high salt intake, and low-level physical activity may be important as well. Some novel risk factors, including hypovitaminosis D, arsenic contamination in water and food-stuff, particulate matter air pollution may play unique role. At the advent of the new millennium, we know little about our real situation. Largescale epidemiological, genetic and clinical researches are needed to explore the different aspects of CAD in Bangladesh. PMID:23993003

Structure of Ljungan virus provides insight into genome packaging of this picornavirus.

PubMed

Zhu, Ling; Wang, Xiangxi; Ren, Jingshan; Porta, Claudine; Wenham, Hannah; Ekström, Jens-Ola; Panjwani, Anusha; Knowles, Nick J; Kotecha, Abhay; Siebert, C Alistair; Lindberg, A Michael; Fry, Elizabeth E; Rao, Zihe; Tuthill, Tobias J; Stuart, David I

2015-10-08

Picornaviruses are responsible for a range of human and animal diseases, but how their RNA genome is packaged remains poorly understood. A particularly poorly studied group within this family are those that lack the internal coat protein, VP4. Here we report the atomic structure of one such virus, Ljungan virus, the type member of the genus Parechovirus B, which has been linked to diabetes and myocarditis in humans. The 3.78-Å resolution cryo-electron microscopy structure shows remarkable features, including an extended VP1 C terminus, forming a major protuberance on the outer surface of the virus, and a basic motif at the N terminus of VP3, binding to which orders some 12% of the viral genome. This apparently charge-driven RNA attachment suggests that this branch of the picornaviruses uses a different mechanism of genome encapsidation, perhaps explored early in the evolution of picornaviruses.

Migration of Apicomplexa Across Biological Barriers: The Toxoplasma and Plasmodium Rides

PubMed Central

Tardieux, Isabelle; Ménard, Robert

2008-01-01

The invasive stages of Apicomplexa parasites, called zoites, have been largely studied in in vitro systems, with a special emphasis on their unique gliding and host cell invasive capacities. In contrast, the means by which these parasites reach their destination in their hosts are still poorly understood. We summarize here our current understanding of the cellular basis of in vivo parasitism by two well-studied Apicomplexa zoites, the Toxoplasma tachyzoite and the Plasmodium sporozoite. Despite being close relatives, these two zoites use different strategies to reach their goal and establish infection. PMID:18194412

The cellular basis for animal regeneration

PubMed Central

Tanaka, Elly; Reddien, Peter W.

2011-01-01

The ability of animals to regenerate missing parts is a dramatic and poorly understood aspect of biology. The sources of new cells for these regenerative phenomena have been sought for decades. Recent advances involving cell fate tracking in complex tissues have shed new light on the cellular underpinnings of regeneration in Hydra, planarians, zebrafish, Xenopus, and Axolotl. Planarians accomplish regeneration with use of adult pluripotent stem cells, whereas several vertebrates utilize a collection of lineage-restricted progenitors from different tissues. Together, an array of cellular strategies—from pluripotent stem cells to tissue-specific stem cells and dedifferentiation—are utilized for regeneration. PMID:21763617

The public's belief about biology.

PubMed

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

EPA Science Inventory

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...

Gender, aging and longevity in humans: an update of an intriguing/neglected scenario paving the way to a gender-specific medicine

PubMed Central

Ostan, Rita; Monti, Daniela; Gueresi, Paola; Bussolotto, Mauro; Franceschi, Claudio

2016-01-01

Data showing a remarkable gender difference in life expectancy and mortality, including survival to extreme age, are reviewed starting from clinical and demographic data and stressing the importance of a comprehensive historical perspective and a gene–environment/lifestyle interaction. Gender difference regarding prevalence and incidence of the most important age-related diseases, such as cardiovascular and neurodegenerative diseases, cancer, Type 2 diabetes, disability, autoimmunity and infections, are reviewed and updated with particular attention to the role of the immune system and immunosenescence. On the whole, gender differences appear to be pervasive and still poorly considered and investigated despite their biomedical relevance. The basic biological mechanisms responsible for gender differences in aging and longevity are quite complex and still poorly understood. The present review focuses on centenarians and their offspring as a model of healthy aging and summarizes available knowledge on three basic biological phenomena, i.e. age-related X chromosome inactivation skewing, gut microbiome changes and maternally inherited mitochondrial DNA genetic variants. In conclusion, an appropriate gender-specific medicine approach is urgently needed and should be systematically pursued in studies on healthy aging, longevity and age-related diseases, in a globalized world characterized by great gender differences which have a high impact on health and diseases. PMID:27555614

Genetics and epigenetics of rheumatoid arthritis

PubMed Central

Viatte, Sebastien; Plant, Darren; Raychaudhuri, Soumya

2013-01-01

Investigators have made key advances in rheumatoid arthritis (RA) genetics in the past 10 years. Although genetic studies have had limited influence on clinical practice and drug discovery, they are currently generating testable hypotheses to explain disease pathogenesis. Firstly, we review here the major advances in identifying RA genetic susceptibility markers both within and outside of the MHC. Understanding how genetic variants translate into pathogenic mechanisms and ultimately into phenotypes remains a mystery for most of the polymorphisms that confer susceptibility to RA, but functional data are emerging. Interplay between environmental and genetic factors is poorly understood and in need of further investigation. Secondly, we review current knowledge of the role of epigenetics in RA susceptibility. Differences in the epigenome could represent one of the ways in which environmental exposures translate into phenotypic outcomes. The best understood epigenetic phenomena include post-translational histone modifications and DNA methylation events, both of which have critical roles in gene regulation. Epigenetic studies in RA represent a new area of research with the potential to answer unsolved questions. PMID:23381558

Connecting marine ecosystem services to human well-being: insights from participatory well-being assessment in Kenya.

PubMed

Abunge, Caroline; Coulthard, Sarah; Daw, Tim M

2013-12-01

The linkage between ecosystems and human well-being is a focus of the conceptualization of "ecosystem services" as promoted by the Millennium Ecosystem Assessment. However, the actual nature of connections between ecosystems and the well-being of individuals remains complex and poorly understood. We conducted a series of qualitative focus groups with five different stakeholder groups connected to a small-scale Kenyan coastal fishery to understand (1) how well-being is understood within the community, and what is important for well-being, (2) how people's well-being has been affected by changes over the recent past, and (3) people's hopes and aspirations for their future fishery. Our results show that people conceive well-being in a diversity of ways, but that these can clearly map onto the MA framework. In particular, our research unpacks the "freedoms and choices" element of the framework and argues for greater recognition of these aspects of well-being in fisheries management in Kenya through, for example, more participatory governance processes.

Blaming the helpers: the marginalization of teachers and parents of the urban poor.

PubMed

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.

Chemical kinetics and modeling of planetary atmospheres

NASA Technical Reports Server (NTRS)

Yung, Yuk L.

1990-01-01

A unified overview is presented for chemical kinetics and chemical modeling in planetary atmospheres. The recent major advances in the understanding of the chemistry of the terrestrial atmosphere make the study of planets more interesting and relevant. A deeper understanding suggests that the important chemical cycles have a universal character that connects the different planets and ultimately link together the origin and evolution of the solar system. The completeness (or incompleteness) of the data base for chemical kinetics in planetary atmospheres will always be judged by comparison with that for the terrestrial atmosphere. In the latter case, the chemistry of H, O, N, and Cl species is well understood. S chemistry is poorly understood. In the atmospheres of Jovian planets and Titan, the C-H chemistry of simple species (containing 2 or less C atoms) is fairly well understood. The chemistry of higher hydrocarbons and the C-N, P-N chemistry is much less understood. In the atmosphere of Venus, the dominant chemistry is that of chlorine and sulfur, and very little is known about C1-S coupled chemistry. A new frontier for chemical kinetics both in the Earth and planetary atmospheres is the study of heterogeneous reactions. The formation of the ozone hole on Earth, the ubiquitous photochemical haze on Venus and in the Jovian planets and Titan all testify to the importance of heterogeneous reactions. It remains a challenge to connect the gas phase chemistry to the production of aerosols.

PHYTOASSESSMENT OF ESTUARINE SEDIMENTS

EPA Science Inventory

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

EPA Science Inventory

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...

Plantation management intensity affects belowground carbon and nitrogen storage in northern California

Treesearch

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

EPA Science Inventory

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...

Activity-Induced Remodeling of Olfactory Bulb Microcircuits Revealed by Monosynaptic Tracing

PubMed Central

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

Jets and Water Clouds on Jupiter

NASA Astrophysics Data System (ADS)

Lian, Yuan; Showman, A. P.

2012-10-01

Ground-based and spacecraft observations show that Jupiter exhibits multiple banded zonal jet structures. These banded jets correlate with dark and bright clouds, often called "belts" and "zones". The mechanisms that produce these banded zonal jets and clouds are poorly understood. Our previous studies showed that the latent heat released by condensation of water vapor could produce equatorial superrotation along with multiple zonal jets in the mid-to-high latitudes. However, that previous work assumed complete and instant removal of condensate and therefore could not predict the cloud formation. Here we present an improved 3D Jupiter model to investigate some effects of cloud microphysics on large-scale dynamics using a closed water cycle that includes condensation, three-dimensional advection of cloud material by the large-scale circulation, evaporation and sedimentation. We use a dry convective adjustment scheme to adjust the temperature towards a dry adiabat when atmospheric columns become convectively unstable, and the tracers are mixed within the unstable layers accordingly. Other physics parameterizations included in our model are the bottom drag and internal heat flux as well as the choices of either Newtonian heating scheme or gray radiative transfer. Given the poorly understood cloud microphysics, we perform case studies by treating the particle size and condensation/evaporation time scale as free parameters. We find that, in some cases, the active water cycle can produce multiple banded jets and clouds. However, the equatorial jet is generally very weak in all the cases because of insufficient supply of eastward eddy momentum fluxes. These differences may result from differences in the overall vertical stratification, baroclinicity, and moisture distribution in our new models relative to the older ones; we expect to elucidate the dynamical mechanisms in continuing work.

The Ocean's Role in Outlet Glacier Variability: A Case Study from Uummannaq, Greenland

NASA Astrophysics Data System (ADS)

Sutherland, D.; Catania, G. A.; Bartholomaus, T. C.; Nash, J. D.; Shroyer, E.; Walker, R. T.; Stearns, L. A.

2014-12-01

The dynamics controlling the coupling between fjord circulation and outlet glacier movement are poorly understood. Here, we use oceanographic data collected from 2013-2014 from two west Greenland fjords, Rink Isbrae and Kangerdlugssup Sermerssua, to constrain the spatial and temporal variability observed in fjord circulation. We aim to quantify the ocean's role, if any, in explaining the marked differences in glacier behavior from two systems that are in close proximity to one another. Combining time series data from a set of subsurface moorings with repeat transects in each fjord allows an unprecedented look at the temporal and spatial variability in circulation. We find significant differences in the variability in each fjord and discuss the implications for the glaciers.

Does the nature of the definitive impression material influence the outcome of (mandibular) complete dentures?

PubMed

McCord, J Fraser; McNally, Lisa M; Smith, Philip W; Grey, Nicholas J A

2005-09-01

The effects of impression materials on the outcome of complete dentures are poorly understood. This double-blind cross-over randomized controlled trial investigated eleven adult edentulous patients. Each received a maxillary denture and three mandibular dentures (which differed only in the three materials used to record the definitive impressions). The three mandibular dentures were given in a random order. Patients' opinions of each denture were recorded using a Linear Analogue Scale. There was a statistically-significant difference between the outcome of the dentures constructed when zinc-oxide eugenol was used, this material being least favoured (p < 0.001). It would therefore appear that care should be exercised when selecting impression materials when constructing mandibular complete dentures.

Gender differences in children's problem behaviours in competitive play with friends.

PubMed

Ensor, Rosie; Hart, Martha; Jacobs, Lorna; Hughes, Claire

2011-06-01

Disruptive behaviour disorders are much more common in boys than girls (Office of National Statistics, 1999); in contrast, gender differences in normative problem behaviours are poorly understood. To address this issue, 228 6-year-olds (134 boys, 94 girls) were each observed playing a board game with a same-gender friend. Ratings of aggression, disruption, arousal and negativity were used to index problem behaviours. Multiple-groups confirmatory factor analyses demonstrated that the latent factor had the same metric for boys and girls, but a mean that was approximately half a standard deviation higher for boys than girls. In addition, the association between the latent factor and teachers' ratings of total difficulties was significantly stronger for boys than girls.

Disentangling the Role of Entanglement Density and Molecular Alignment in the Mechanical Response of Glassy Polymers

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.

A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment.

PubMed

van der Heijden, Marcel G A; de Bruin, Susanne; Luckerhoff, Ludo; van Logtestijn, Richard S P; Schlaeppi, Klaus

2016-02-01

Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions.

Gender differences and pain medication.

PubMed

Richardson, Jen; Holdcroft, Anita

2009-01-01

Subtle genetic and psychological variations are increasingly recognized to contribute to pain and analgesic efficacy and safety. The influence of sex on this relationship remains poorly understood, particularly in humans. The issue is complicated by the overlay of gender onto physical sex, and its associated stereotypes and expectations. Women appear to use more pain-relieving medications than men; however, it remains unclear whether these observations represent true differences in analgesic usage patterns, or reporting bias. Differences in analgesic efficacy relating to body composition, metabolism and hormonal profiles have been demonstrated. Psychological and social elements of gender have also been associated with altered pain experiences and analgesic use profiles, albeit with significant individual variations. Intra-group differences may ultimately prove more important than sex differences. Further research may unravel the various threads linking gender and sex effects on analgesia with the aim of individualizing analgesia to optimize pain relief.

Cryotolerance of stallion spermatozoa is related to ROS production and mitochondrial membrane potential rather than to the integrity of sperm nucleus.

PubMed

Yeste, M; Estrada, E; Rocha, L G; Marín, H; Rodríguez-Gil, J E; Miró, J

2015-03-01

Although cryopreservation of stallion spermatozoa allows long-term preservation of spermatozoa from particular stallions and facilitates international trade, it is understood to inflict damages on sperm cells that may finally reduce their fertilizing ability. In addition, individual differences are known to exist in the sperm ability to withstand freeze-thawing protocols. To date, these differences have mainly been reported on the basis of sperm motility and membrane integrity. For this reason, the present work sought to determine differences between good (good freezability ejaculates: GFE) and poor (poor freezability ejaculates: PFE) freezability stallion ejaculates in other sperm parameters, including peroxide and superoxide levels, potential of mitochondrial membrane and nuclear integrity. With this purpose, a total of 24 stallion ejaculates were cryopreserved and classified into two groups (GFE vs. PFE), depending on their sperm membrane integrity and motility after freeze-thawing. From the total of 24 ejaculates, 13 were classified as GFE and the other 11 were classified as PFE. Apart from differences in sperm membrane permeability and lipid disorder after freeze-thawing, GFE presented significantly (p < 0.05) higher percentages of viable spermatozoa with high content of peroxides and of superoxides than PFE. In contrast, and despite cryopreservation of stallion spermatozoa increasing DNA fragmentation and disrupting disulphide bonds in sperm head proteins, no significant differences between GFE and PFE were seen. We can thus conclude that good and poor freezability stallion ejaculates differ in their reactive oxygen species levels after cryopreservation, but not in the damage extent on sperm nucleus. © 2014 American Society of Andrology and European Academy of Andrology.

Tracking contaminant flux from aquatic to terrestrial food webs

EPA Science Inventory

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

EPA Science Inventory

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

EPA Science Inventory

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

EPA Science Inventory

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...

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.

AN IMPROVED METHOD FOR DETECTING VIRUSES IN WATER

EPA Science Inventory

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.

PubMed

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.

Loneliness in psychosis: a systematic review.

PubMed

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).

Lags in the response of mountain plant communities to climate change

PubMed Central

Alexander, Jake M.; Chalmandrier, Loïc; Lenoir, Jonathan; Burgess, Treena I.; Essl, Franz; Haider, Sylvia; Kueffer, Christoph; McDougall, Keith; Milbau, Ann; Nuñez, Martin A.; Pauchard, Aníbal; Rabitsch, Wolfgang; Rew, Lisa J.; Sanders, Nathan J.; Pellissier, Loïc

2018-01-01

Rapid climatic changes and increasing human influence at high elevations around the world will have profound impacts on mountain biodiversity. However, forecasts from statistical models (e.g. species distribution models) rarely consider that plant community changes could substantially lag behind climatic changes, hindering our ability to make temporally realistic projections for the coming century. Indeed, the magnitudes of lags, and the relative importance of the different factors giving rise to them, remain poorly understood. We review evidence for three types of lag: “dispersal lags” affecting plant species’ spread along elevational gradients, “establishment lags” following their arrival in recipient communities, and “extinction lags” of resident species. Variation in lags is explained by variation among species in physiological and demographic responses, by effects of altered biotic interactions, and by aspects of the physical environment. Of these, altered biotic interactions could contribute substantially to establishment and extinction lags, yet impacts of biotic interactions on range dynamics are poorly understood. We develop a mechanistic community model to illustrate how species turnover in future communities might lag behind simple expectations based on species’ range shifts with unlimited dispersal. The model shows a combined contribution of altered biotic interactions and dispersal lags to plant community turnover along an elevational gradient following climate warming. Our review and simulation support the view that accounting for disequilibrium range dynamics will be essential for realistic forecasts of patterns of biodiversity under climate change, with implications for the conservation of mountain species and the ecosystem functions they provide. PMID:29112781

Continuous-variable quantum key distribution protocols over noisy channels.

PubMed

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.

Ultrashort Nucleic Acid Duplexes Exhibit Long Wormlike Chain Behavior with Force-Dependent Edge Effects

NASA Astrophysics Data System (ADS)

Whitley, Kevin D.; Comstock, Matthew J.; Chemla, Yann R.

2018-02-01

Despite their importance in biology and use in nanotechnology, the elastic behavior of nucleic acids on "ultrashort" (<15 nt ) length scales remains poorly understood. Here, we use optical tweezers combined with fluorescence imaging to observe directly the hybridization of oligonucleotides (7-12 nt) to a complementary strand under tension and to measure the difference in end-to-end extension between the single-stranded and duplex states. Data are consistent with long-polymer models at low forces (<8 pN ) but smaller than predicted at higher forces (>8 pN ), the result of the sequence-dependent duplex edge effects.

Analysis of high quality superconducting resonators: consequences for TLS properties in amorphous oxides

NASA Astrophysics Data System (ADS)

Burnett, J.; Faoro, L.; Lindström, T.

2016-04-01

1/f noise caused by microscopic two-level systems (TLS) is known to be very detrimental to the performance of superconducting quantum devices but the nature of these TLS is still poorly understood. Recent experiments with superconducting resonators indicates that interaction between TLS in the oxide at the film-substrate interface is not negligible. Here we present data on the loss and 1/f frequency noise from two different Nb resonators with and without Pt capping and discuss what conclusions can be drawn regarding the properties of TLS in amorphous oxides. We also estimate the concentration and dipole moment of the TLS.

Differentiation of emotions in laughter at the behavioral level.

PubMed

Szameitat, Diana P; Alter, Kai; Szameitat, André J; Darwin, Chris J; Wildgruber, Dirk; Dietrich, Susanne; Sterr, Annette

2009-06-01

Although laughter is important in human social interaction, its role as a communicative signal is poorly understood. Because laughter is expressed in various emotional contexts, the question arises as to whether different emotions are communicated. In the present study, participants had to appraise 4 types of laughter sounds (joy, tickling, taunting, schadenfreude) either by classifying them according to the underlying emotion or by rating them according to different emotional dimensions. The authors found that emotions in laughter (a) can be classified into different emotional categories, and (b) can have distinctive profiles on W. Wundt's (1905) emotional dimensions. This shows that laughter is a multifaceted social behavior that can adopt various emotional connotations. The findings support the postulated function of laughter in establishing group structure, whereby laughter is used either to include or to exclude individuals from group coherence.

Proton electrochemical gradient: Driving and regulating neurotransmitter uptake.

PubMed

Farsi, Zohreh; Jahn, Reinhard; Woehler, Andrew

2017-05-01

Accumulation of neurotransmitters in the lumen of synaptic vesicles (SVs) relies on the activity of the vacuolar-type H + -ATPase. This pump drives protons into the lumen, generating a proton electrochemical gradient (Δμ H+ ) across the membrane. Recent work has demonstrated that the balance between the chemical (ΔpH) and electrical (ΔΨ) components of Δμ H+ is regulated differently by some distinct vesicle types. As different neurotransmitter transporters use ΔpH and ΔΨ with different relative efficiencies, regulation of this gradient balance has the potential to influence neurotransmitter uptake. Nevertheless, the underlying mechanisms responsible for this regulation remain poorly understood. In this review, we provide an overview of current neurotransmitter uptake models, with a particular emphasis on the distinct roles of the electrical and chemical gradients and current hypotheses for regulatory mechanisms. © 2017 WILEY Periodicals, Inc.

Predictive Models of Nanotoxicity: Relationship of Physicochemical Properties to Particle Movement Through Biological Barriers

EPA Science Inventory

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

EPA Science Inventory

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...

Ankle ligament injuries.

PubMed

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.

Whole Genome Analysis of a Wine Yeast Strain

PubMed Central

Hauser, Nicole C.; Fellenberg, Kurt; Gil, Rosario; Bastuck, Sonja; Hoheisel, Jörg D.

2001-01-01

Saccharomyces cerevisiae strains frequently exhibit rather specific phenotypic features needed for adaptation to a special environment. Wine yeast strains are able to ferment musts, for example, while other industrial or laboratory strains fail to do so. The genetic differences that characterize wine yeast strains are poorly understood, however. As a first search of genetic differences between wine and laboratory strains, we performed DNA-array analyses on the typical wine yeast strain T73 and the standard laboratory background in S288c. Our analysis shows that even under normal conditions, logarithmic growth in YPD medium, the two strains have expression patterns that differ significantly in more than 40 genes. Subsequent studies indicated that these differences correlate with small changes in promoter regions or variations in gene copy number. Blotting copy numbers vs. transcript levels produced patterns, which were specific for the individual strains and could be used for a characterization of unknown samples. PMID:18628902

Express yourself: bold individuals induce enhanced morphological defences

PubMed Central

Hulthén, Kaj; Chapman, Ben B.; Nilsson, P. Anders; Hollander, Johan; Brönmark, Christer

2014-01-01

Organisms display an impressive array of defence strategies in nature. Inducible defences (changes in morphology and/or behaviour within a prey's lifetime) allow prey to decrease vulnerability to predators and avoid unnecessary costs of expression. Many studies report considerable interindividual variation in the degree to which inducible defences are expressed, yet what underlies this variation is poorly understood. Here, we show that individuals differing in a key personality trait also differ in the magnitude of morphological defence expression. Crucian carp showing risky behaviours (bold individuals) expressed a significantly greater morphological defence response when exposed to a natural enemy when compared with shy individuals. Furthermore, we show that fish of different personality types differ in their behavioural plasticity, with shy fish exhibiting greater absolute plasticity than bold fish. Our data suggest that individuals with bold personalities may be able to compensate for their risk-prone behavioural type by expressing enhanced morphological defences. PMID:24335987

Distinct lateral inhibitory circuits drive parallel processing of sensory information in the mammalian olfactory bulb

PubMed Central

Geramita, Matthew A; Burton, Shawn D; Urban, Nathan N

2016-01-01

Splitting sensory information into parallel pathways is a common strategy in sensory systems. Yet, how circuits in these parallel pathways are composed to maintain or even enhance the encoding of specific stimulus features is poorly understood. Here, we have investigated the parallel pathways formed by mitral and tufted cells of the olfactory system in mice and characterized the emergence of feature selectivity in these cell types via distinct lateral inhibitory circuits. We find differences in activity-dependent lateral inhibition between mitral and tufted cells that likely reflect newly described differences in the activation of deep and superficial granule cells. Simulations show that these circuit-level differences allow mitral and tufted cells to best discriminate odors in separate concentration ranges, indicating that segregating information about different ranges of stimulus intensity may be an important function of these parallel sensory pathways. DOI: http://dx.doi.org/10.7554/eLife.16039.001 PMID:27351103

Ion track etching revisited: I. Correlations between track parameters in aged polymers

NASA Astrophysics Data System (ADS)

Fink, D.; Muñoz H., G.; García A., H.; Vacik, J.; Hnatowicz, V.; Kiv, A.; Alfonta, L.

2018-04-01

Some yet poorly understood problems of etching of pristine and swift heavy ion track-irradiated aged polymers were treated, by applying conductometry across the irradiated foils during etching. The onset times of etchant penetration across pristine foils, and the onset times of the different etched track regimes in irradiated foils were determined for polymers of various proveniences, fluences and ages, as well as their corresponding etching speeds. From the results, correlations of the parameters with each other were deduced. The normalization of these parameters enables one to compare irradiated polymer foils of different origin and treatment with one another. In a number of cases, also polymeric gel formation and swelling occur which influence the track etching behaviour. The polymer degradation during aging influences the track etching parameters, which differ from each other on both sides of the foils. With increasing sample age, these differences increase.

Perfectionism related to self-reported insomnia severity, but not when controlled for stress and emotion regulation.

PubMed

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.

Perfectionism related to self-reported insomnia severity, but not when controlled for stress and emotion regulation

PubMed Central

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

Higher frequency of genetic variants conferring increased risk for ADRs for commonly used drugs treating cancer, AIDS and tuberculosis in persons of African descent.

PubMed

Aminkeng, F; Ross, C J D; Rassekh, S R; Brunham, L R; Sistonen, J; Dube, M-P; Ibrahim, M; Nyambo, T B; Omar, S A; Froment, A; Bodo, J-M; Tishkoff, S; Carleton, B C; Hayden, M R

2014-04-01

There is established clinical evidence for differences in drug response, cure rates and survival outcomes between different ethnic populations, but the causes are poorly understood. Differences in frequencies of functional genetic variants in key drug response and metabolism genes may significantly influence drug response differences in different populations. To assess this, we genotyped 1330 individuals of African (n=372) and European (n=958) descent for 4535 single-nucleotide polymorphisms in 350 key drug absorption, distribution, metabolism, elimination and toxicity genes. Important and remarkable differences in the distribution of genetic variants were observed between Africans and Europeans and among the African populations. These could translate into significant differences in drug efficacy and safety profiles, and also in the required dose to achieve the desired therapeutic effect in different populations. Our data points to the need for population-specific genetic variation in personalizing medicine and care.

Higher frequency of genetic variants conferring increased risk for ADRs for commonly used drugs treating cancer, AIDS and tuberculosis in persons of African descent

PubMed Central

Aminkeng, F; Ross, CJD; Rassekh, SR; Brunham, LR; Sistonen, J; Dube, M-P; Ibrahim, M; Nyambo, TB; Omar, SA; Froment, A; Bodo, J-M; Tishkoff, S; Carleton, BC; Hayden, MR

2015-01-01

There is established clinical evidence for differences in drug response, cure rates and survival outcomes between different ethnic populations, but the causes are poorly understood. Differences in frequencies of functional genetic variants in key drug response and metabolism genes may significantly influence drug response differences in different populations. To assess this, we genotyped 1330 individuals of African (n = 372) and European (n = 958) descent for 4535 single-nucleotide polymorphisms in 350 key drug absorption, distribution, metabolism, elimination and toxicity genes. Important and remarkable differences in the distribution of genetic variants were observed between Africans and Europeans and among the African populations. These could translate into significant differences in drug efficacy and safety profiles, and also in the required dose to achieve the desired therapeutic effect in different populations. Our data points to the need for population-specific genetic variation in personalizing medicine and care. PMID:23588107

Where Lies the Risk? An Ecological Approach to Understanding Child Mental Health Risk and Vulnerabilities in Sub-Saharan Africa

PubMed Central

Atilola, Olayinka

2014-01-01

Efforts at improving child-health and development initiatives in sub-Saharan Africa had focused on the physical health of children due to the neglect of child and adolescent mental health (CAMH) policy initiatives. A thorough and broad-based understanding of the prevalent child mental-health risk and vulnerability factors is needed to successfully articulate CAMH policies. In this discourse, we present a narrative on the child mental-health risk and vulnerability factors in sub-Saharan Africa. Through an ecological point of view, we identified widespread family poverty, poor availability and uptake of childcare resources, inadequate community and institutional childcare systems, and inadequate framework for social protection for vulnerable children as among the risk and vulnerability factors for CAMH in the region. Others are poor workplace policy/practice that does not support work-family life balance, poor legislative framework for child protection, and some harmful traditional practices. We conclude that an ecological approach shows that child mental-health risks are diverse and cut across different layers of the care environment. The approach also provides a broad and holistic template from which appropriate CAMH policy direction in sub-Saharan Africa can be understood. PMID:24834431

Where lies the risk? An ecological approach to understanding child mental health risk and vulnerabilities in sub-saharan Africa.

PubMed

Atilola, Olayinka

2014-01-01

Efforts at improving child-health and development initiatives in sub-Saharan Africa had focused on the physical health of children due to the neglect of child and adolescent mental health (CAMH) policy initiatives. A thorough and broad-based understanding of the prevalent child mental-health risk and vulnerability factors is needed to successfully articulate CAMH policies. In this discourse, we present a narrative on the child mental-health risk and vulnerability factors in sub-Saharan Africa. Through an ecological point of view, we identified widespread family poverty, poor availability and uptake of childcare resources, inadequate community and institutional childcare systems, and inadequate framework for social protection for vulnerable children as among the risk and vulnerability factors for CAMH in the region. Others are poor workplace policy/practice that does not support work-family life balance, poor legislative framework for child protection, and some harmful traditional practices. We conclude that an ecological approach shows that child mental-health risks are diverse and cut across different layers of the care environment. The approach also provides a broad and holistic template from which appropriate CAMH policy direction in sub-Saharan Africa can be understood.

Mineral potential for incompatible element deposits hosted in pegmatites, alkaline rocks, and carbonatites in the Islamic Republic of Mauritania (phase V, deliverable 87): Chapter Q in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)

USGS Publications Warehouse

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).

PubMed

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

EPA Science Inventory

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

EPA Science Inventory

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.

PubMed

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

EPA Science Inventory

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 ...

DISSECTING COLONY DEVELOPMENT OF NEUROSPORA CRASSA USING mRNA PROFILING AND COMPARTATIVE GENOMICS APPROACHES

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

EPA Science Inventory

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

EPA Science Inventory

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

DTIC Science & Technology

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)

EPA Science Inventory

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.

PubMed

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.

Effects of ecosystem development on benthic secondary production in restored and created mangrove habitats

EPA Science Inventory

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

EPA Science Inventory

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

EPA Science Inventory

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

EPA Science Inventory

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 ...

REVIEW OF QUANTITATIVE STANDARDS AND GUIDELINES FOR FUNGI IN INDOOR AIR

EPA Science Inventory

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...

Gender, aging and longevity in humans: an update of an intriguing/neglected scenario paving the way to a gender-specific medicine.

PubMed

Ostan, Rita; Monti, Daniela; Gueresi, Paola; Bussolotto, Mauro; Franceschi, Claudio; Baggio, Giovannella

2016-10-01

Data showing a remarkable gender difference in life expectancy and mortality, including survival to extreme age, are reviewed starting from clinical and demographic data and stressing the importance of a comprehensive historical perspective and a gene-environment/lifestyle interaction. Gender difference regarding prevalence and incidence of the most important age-related diseases, such as cardiovascular and neurodegenerative diseases, cancer, Type 2 diabetes, disability, autoimmunity and infections, are reviewed and updated with particular attention to the role of the immune system and immunosenescence. On the whole, gender differences appear to be pervasive and still poorly considered and investigated despite their biomedical relevance. The basic biological mechanisms responsible for gender differences in aging and longevity are quite complex and still poorly understood. The present review focuses on centenarians and their offspring as a model of healthy aging and summarizes available knowledge on three basic biological phenomena, i.e. age-related X chromosome inactivation skewing, gut microbiome changes and maternally inherited mitochondrial DNA genetic variants. In conclusion, an appropriate gender-specific medicine approach is urgently needed and should be systematically pursued in studies on healthy aging, longevity and age-related diseases, in a globalized world characterized by great gender differences which have a high impact on health and diseases. © 2016 The Author(s).

Changes Over Time in Absolute and Relative Socioeconomic Differences in Smoking: A Comparison of Cohort Studies From Britain, Finland, and Japan

PubMed Central

Pietiläinen, Olli; Ferrie, Jane; Kivimäki, Mika; Lahti, Jouni; Marmot, Michael; Rahkonen, Ossi; Sekine, Michikazu; Shipley, Martin; Tatsuse, Takashi; Lallukka, Tea

2016-01-01

Introduction: Socioeconomic differences in smoking over time and across national contexts are poorly understood. We assessed the magnitude of relative and absolute social class differences in smoking in cohorts from Britain, Finland, and Japan over 5–7 years. Methods: The British Whitehall II study (n = 4350), Finnish Helsinki Health Study (n = 6328), and Japanese Civil Servants Study (n = 1993) all included employed men and women aged 35–68 at baseline in 1997–2002. Follow-up was in 2003–2007 (mean follow-up 5.1, 6.5, and 3.6 years, respectively). Occupational social class (managers, professionals and clerical employees) was measured at baseline. Current smoking and covariates (age, marital status, body mass index, and self-rated health) were measured at baseline and follow-up. We assessed relative social class differences using the Relative Index of Inequality and absolute differences using the Slope Index of Inequality. Results: Social class differences in smoking were found in Britain and Finland, but not in Japan. Age-adjusted relative differences at baseline ranged from Relative Index of Inequality 3.08 (95% confidence interval 1.99–4.78) among Finnish men to 2.32 (1.24–4.32) among British women, with differences at follow-up greater by 8%–58%. Absolute differences remained stable and varied from Slope Index of Inequality 0.27 (0.15–0.40) among Finnish men to 0.10 (0.03–0.16) among British women. Further adjustment for covariates had modest effects on inequality indices. Conclusions: Large social class differences in smoking persisted among British and Finnish men and women, with widening tendencies in relative differences over time. No differences could be confirmed among Japanese men or women. Implications: Changes over time in social class differences in smoking are poorly understood across countries. Our study focused on employees from Britain, Finland and Japan, and found relative and absolute and class differences among British and Finnish men and women. Key covariates had modest effects on the differences. Relative differences tended to widen over the 4- to 7-year follow-up, whereas absolute differences remained stable. In contrast, class differences in smoking among Japanese men or women were not found. Britain and Finland are at the late stage of the smoking epidemic model, whereas Japan may not follow the same model. PMID:26764256

Comprehensive Characterization of Molecular Differences in Cancer between Male and Female Patients

PubMed Central

Yuan, Yuan; Liu, Lingxiang; Chen, Hu; Wang, Yumeng; Xu, Yanxun; Mao, Huzhang; Li, Jun; Mills, Gordon B.; Shu, Yongqian; Li, Liang; Liang, Han

2016-01-01

Summary An individual’s sex has been long recognized as a key factor affecting cancer incidence, prognosis and treatment responses. However, the molecular basis for sex disparities in cancer remains poorly understood. We performed a comprehensive analysis of molecular differences between male and female patients in 13 cancer types of The Cancer Genome Atlas and revealed two sex-effect groups associated with distinct incidence and mortality profiles. One group contains a small number of sex-affected genes, whereas the other shows much more extensive sex-biased molecular signatures. Importantly, 53% of clinically actionable genes (60/114) show sex-biased signatures. Our study provides a systematic molecular-level understanding of sex effects in diverse cancers and suggests a pressing need to develop sex-specific therapeutic strategies in certain cancer types. PMID:27165743

Neural correlates of socioeconomic status in the developing human brain.

PubMed

Noble, Kimberly G; Houston, Suzanne M; Kan, Eric; Sowell, Elizabeth R

2012-07-01

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 language, memory, social-emotional processing, and cognitive control exhibit relatively large differences across SES. Here we investigated whether volumetric differences could be observed across SES in several neural regions that support these skills. In a sample of 60 socioeconomically diverse children, highly significant SES differences in regional brain volume were observed in the hippocampus and the amygdala. In addition, SES × age interactions were observed in the left superior temporal gyrus and left inferior frontal gyrus, suggesting increasing SES differences with age in these regions. These results were not explained by differences in gender, race or IQ. Likely mechanisms include differences in the home linguistic environment and exposure to stress, which may serve as targets for intervention at a time of high neural plasticity. © 2012 Blackwell Publishing Ltd.

Whole-genome sequencing provides new insights into the clonal architecture of Barrett’s esophagus and esophageal adenocarcinoma

PubMed Central

Warren, Andrew; Cheetham, R. Keira; Northen, Helen; O’Donovan, Maria; Malhotra, Shalini; di Pietro, Massimiliano; Ivakhno, Sergii; He, Miao; Weaver, Jamie M.J.; Lynch, Andy G.; Kingsbury, Zoya; Ross, Mark; Humphray, Sean; Bentley, David; Fitzgerald, Rebecca C.

2015-01-01

The molecular genetic relationship between esophageal adenocarcinoma (EAC) and its precursor lesion, Barrett’s esophagus, is poorly understood. Using whole-genome sequencing on 23 paired Barrett’s esophagus and EAC samples, together with one in-depth Barrett’s esophagus case-study sampled over time and space, we have provided new insights on the following aspects: i) Barrett’s esophagus is polyclonal and highly mutated even in the absence of dysplasia; ii) when cancer develops, copy number increases and heterogeneity persists such that the spectrum of mutations often shows surprisingly little overlap between EAC and adjacent Barrett’s esophagus; and iii) despite differences in specific coding mutations the mutational context suggests a common causative insult underlying these two conditions. From a clinical perspective, the histopathological assessment of dysplasia appears to be a poor reflection of the molecular disarray within the Barrett’s epithelium and a molecular Cytosponge™ technique overcomes sampling bias and has capacity to reflect the entire clonal architecture. PMID:26192915

The impacts of livestock diseases and their control on growth and development processes that are pro-poor

PubMed Central

Perry, Brian; Grace, Delia

2009-01-01

Poverty is now at the heart of development discourse; we discuss how it is measured and understood. We next consider the negative and positive impacts of livestock on pro-poor development. Taking a value-chain approach that includes keepers, users and eaters of livestock, we identify diseases that are road blocks on the ‘three livestock pathways out of poverty’. We discuss livestock impacts on poverty reduction and review attempts to prioritize the livestock diseases relevant to the poor. We make suggestions for metrics that better measure disease impact and show the benefits of more rigorous evaluation before reviewing recent attempts to measure the importance of disease to the poor. High impact of a disease does not guarantee high benefits from its control; other factors must be taken into consideration, including technical feasibility and political desirability. We conclude by considering how we might better understand and exploit the roles of livestock and improved animal health by posing three speculative questions on the impact of livestock diseases and their control on global poverty: how can understanding livestock and poverty links help disease control?; if global poverty reduction was the aim of livestock disease control, how would it differ from the current model?; and how much of the impact of livestock disease on poverty is due to disease control policy rather than disease itself? PMID:19687035

Altitudinal divergence in maternal thermoregulatory behaviour may be driven by differences in selection on offspring survival in a viviparous lizard.

PubMed

Uller, Tobias; While, Geoffrey M; Cadby, Chloe D; Harts, Anna; O'Connor, Katherine; Pen, Ido; Wapstra, Erik

2011-08-01

Plastic responses to temperature during embryonic development are common in ectotherms, but their evolutionary relevance is poorly understood. Using a combination of field and laboratory approaches, we demonstrate altitudinal divergence in the strength of effects of maternal thermal opportunity on offspring birth date and body mass in a live-bearing lizard (Niveoscincus ocellatus). Poor thermal opportunity decreased birth weight at low altitudes where selection on body mass was negligible. In contrast, there was no effect of maternal thermal opportunity on body mass at high altitudes where natural selection favored heavy offspring. The weaker effect of poor maternal thermal opportunity on offspring development at high altitude was accompanied by a more active thermoregulation and higher body temperature in highland females. This may suggest that passive effects of temperature on embryonic development have resulted in evolution of adaptive behavioral compensation for poor thermal opportunity at high altitudes, but that direct effects of maternal thermal environment are maintained at low altitudes because they are not selected against. More generally, we suggest that phenotypic effects of maternal thermal opportunity or incubation temperature in reptiles will most commonly reflect weak selection for canalization or selection on maternal strategies rather than adaptive plasticity to match postnatal environments. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

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...

WWW: The Scientific Method

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...

Size matters: The contribution of mega-infauna to the food webs and ecosystem services of an Oregon estuary - ESA

EPA Science Inventory

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...

Environmental enteric dysfunction is associated with carnitine deficiency and altered fatty acid oxidation

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

EPA Science Inventory

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...

Disruption of the circadian clock within the cardiomyocyte influences mycardial contractile function, metabolism, and gene expression

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 ...

Light absorption of secondary organic aerosol: Composition and contribution of nitro-aromatic compounds

EPA Science Inventory

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

Treesearch

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...

The dark side of suibsidies: quantifying contaminant exposure to riparian predators via stream insects

EPA Science Inventory

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

Treesearch

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...

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…

Ecosystem Development after Mangrove Wetland Creation: Plant-Soil Change across a 20-year Chronosequence

EPA Science Inventory

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...

Working Model Hearts

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…

Technology-Enhanced Discovery

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

EPA Science Inventory

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.

PubMed

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.

PubMed

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.

PubMed

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

USGS Publications Warehouse

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.

Inhibiting platelet-derived growth factor beta reduces Ewing's sarcoma growth and metastasis in a novel orthotopic human xenograft model.

PubMed

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.

Acute clinical recovery from sport-related concussion.

PubMed

Nelson, Lindsay D; Janecek, Julie K; McCrea, Michael A

2013-12-01

Concussion is a highly prevalent injury in contact and collision sports that has historically been poorly understood. An influx of sport-concussion research in recent years has led to a dramatic improvement in our understanding of the injury's defining characteristics and natural history of recovery. In this review, we discuss the current state of knowledge regarding the characteristic features of concussion and typical acute course of recovery, with an emphasis on the aspects of functioning most commonly assessed by clinicians and researchers (e.g., symptoms, cognitive deficits, postural stability). While prototypical clinical recovery is becoming better understood, questions remain regarding what factors (e.g., injury severity, demographic variables, history of prior concussions, psychological factors) may explain individual variability in recovery. Although research concerning individual differences in response to concussion is relatively new, and in many cases limited methodologically, we discuss the evidence about several potential moderators of concussion recovery and point out areas for future research. Finally, we describe how increased knowledge about the negative effects of and recovery following concussion has been translated into clinical guidelines for managing concussed athletes.

Obesity and Its Potential Effects on Antidepressant Treatment Outcomes in Patients with Depressive Disorders: A Literature Review

PubMed Central

Woo, Young Sup; Seo, Hye-Jin; McIntyre, Roger S.; Bahk, Won-Myong

2016-01-01

Accumulating evidence regarding clinical, neurobiological, genetic, and environmental factors suggests a bidirectional link between obesity and depressive disorders. Although a few studies have investigated the link between obesity/excess body weight and the response to antidepressants in depressive disorders, the effect of weight on treatment response remains poorly understood. In this review, we summarized recent data regarding the relationship between the response to antidepressants and obesity/excess body weight in clinical studies of patients with depressive disorders. Although several studies indicated an association between obesity/excess body weight and poor antidepressant responses, it is difficult to draw definitive conclusions due to the variability of subject composition and methodological differences among studies. Especially, differences in sex, age and menopausal status, depressive symptom subtypes, and antidepressants administered may have caused inconsistencies in the results among studies. The relationship between obesity/excess body weight and antidepressant responses should be investigated further in high-powered studies addressing the differential effects on subject characteristics and treatment. Moreover, future research should focus on the roles of mediating factors, such as inflammatory markers and neurocognitive performance, which may alter the antidepressant treatment outcome in patients with comorbid obesity and depressive disorder. PMID:26771598

Heart Rate Variability Moderates the Association Between Separation-Related Psychological Distress and Blood Pressure Reactivity Over Time.

PubMed

Bourassa, Kyle J; Hasselmo, Karen; Sbarra, David A

2016-08-01

Divorce is a stressor associated with long-term health risk, though the mechanisms of this effect are poorly understood. Cardiovascular reactivity is one biological pathway implicated as a predictor of poor long-term health after divorce. A sample of recently separated and divorced adults (N = 138) was assessed over an average of 7.5 months to explore whether individual differences in heart rate variability-assessed by respiratory sinus arrhythmia-operate in combination with subjective reports of separation-related distress to predict prospective changes in cardiovascular reactivity, as indexed by blood pressure reactivity. Participants with low resting respiratory sinus arrhythmia at baseline showed no association between divorce-related distress and later blood pressure reactivity, whereas participants with high respiratory sinus arrhythmia showed a positive association. In addition, within-person variation in respiratory sinus arrhythmia and between-persons variation in separation-related distress interacted to predict blood pressure reactivity at each laboratory visit. Individual differences in heart rate variability and subjective distress operate together to predict cardiovascular reactivity and may explain some of the long-term health risk associated with divorce. © The Author(s) 2016.

Systemic Sclerosis-Associated Pulmonary Arterial Hypertension

PubMed Central

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

Effect of bedrock permeability on stream base flow mean transit time scaling relations: 1. A multiscale catchment intercomparison

NASA Astrophysics Data System (ADS)

Hale, V. Cody; McDonnell, Jeffrey J.

2016-02-01

The effect of bedrock permeability and underlying catchment boundaries on stream base flow mean transit time (MTT) and MTT scaling relationships in headwater catchments is poorly understood. Here we examine the effect of bedrock permeability on MTT and MTT scaling relations by comparing 15 nested research catchments in western Oregon; half within the HJ Andrews Experimental Forest and half at the site of the Alsea Watershed Study. The two sites share remarkably similar vegetation, topography, and climate and differ only in bedrock permeability (one poorly permeable volcanic rock and the other more permeable sandstone). We found longer MTTs in the catchments with more permeable fractured and weathered sandstone bedrock than in the catchments with tight, volcanic bedrock (on average, 6.2 versus 1.8 years, respectively). At the permeable bedrock site, 67% of the variance in MTT across catchments scales was explained by drainage area, with no significant correlation to topographic characteristics. The poorly permeable site had opposite scaling relations, where MTT showed no correlation to drainage area but the ratio of median flow path length to median flow path gradient explained 91% of the variance in MTT across seven catchment scales. Despite these differences, hydrometric analyses, including flow duration and recession analysis, and storm response analysis, show that the two sites share relatively indistinguishable hydrodynamic behavior. These results show that similar catchment forms and hydrologic regimes hide different subsurface routing, storage, and scaling behavior—a major issue if only hydrometric data are used to define hydrological similarity for assessing land use or climate change response.

A missed Fe-S cluster handoff causes a metabolic shakeup.

PubMed

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.

The enhancement and suppression of immersion mode heterogeneous ice-nucleation by solutes.

PubMed

Whale, Thomas F; Holden, Mark A; Wilson, Theodore W; O'Sullivan, Daniel; Murray, Benjamin J

2018-05-07

Heterogeneous nucleation of ice from aqueous solutions is an important yet poorly understood process in multiple fields, not least the atmospheric sciences where it impacts the formation and properties of clouds. In the atmosphere ice-nucleating particles are usually, if not always, mixed with soluble material. However, the impact of this soluble material on ice nucleation is poorly understood. In the atmospheric community the current paradigm for freezing under mixed phase cloud conditions is that dilute solutions will not influence heterogeneous freezing. By testing combinations of nucleators and solute molecules we have demonstrated that 0.015 M solutions (predicted melting point depression <0.1 °C) of several ammonium salts can cause suspended particles of feldspars and quartz to nucleate ice up to around 3 °C warmer than they do in pure water. In contrast, dilute solutions of certain alkali metal halides can dramatically depress freezing points for the same nucleators. At 0.015 M, solutes can enhance or deactivate the ice-nucleating ability of a microcline feldspar across a range of more than 10 °C, which corresponds to a change in active site density of more than a factor of 10 5 . This concentration was chosen for a survey across multiple solutes-nucleant combinations since it had a minimal colligative impact on freezing and is relevant for activating cloud droplets. Other nucleators, for instance a silica gel, are unaffected by these 'solute effects', to within experimental uncertainty. This split in response to the presence of solutes indicates that different mechanisms of ice nucleation occur on the different nucleators or that surface modification of relevance to ice nucleation proceeds in different ways for different nucleators. These solute effects on immersion mode ice nucleation may be of importance in the atmosphere as sea salt and ammonium sulphate are common cloud condensation nuclei (CCN) for cloud droplets and are internally mixed with ice-nucleating particles in mixed-phase clouds. In addition, we propose a pathway dependence where activation of CCN at low temperatures might lead to enhanced ice formation relative to pathways where CCN activation occurs at higher temperatures prior to cooling to nucleation temperature.

The enhancement and suppression of immersion mode heterogeneous ice-nucleation by solutes

PubMed Central

Holden, Mark A.; Wilson, Theodore W.; O'Sullivan, Daniel; Murray, Benjamin J.

2018-01-01

Heterogeneous nucleation of ice from aqueous solutions is an important yet poorly understood process in multiple fields, not least the atmospheric sciences where it impacts the formation and properties of clouds. In the atmosphere ice-nucleating particles are usually, if not always, mixed with soluble material. However, the impact of this soluble material on ice nucleation is poorly understood. In the atmospheric community the current paradigm for freezing under mixed phase cloud conditions is that dilute solutions will not influence heterogeneous freezing. By testing combinations of nucleators and solute molecules we have demonstrated that 0.015 M solutions (predicted melting point depression <0.1 °C) of several ammonium salts can cause suspended particles of feldspars and quartz to nucleate ice up to around 3 °C warmer than they do in pure water. In contrast, dilute solutions of certain alkali metal halides can dramatically depress freezing points for the same nucleators. At 0.015 M, solutes can enhance or deactivate the ice-nucleating ability of a microcline feldspar across a range of more than 10 °C, which corresponds to a change in active site density of more than a factor of 105. This concentration was chosen for a survey across multiple solutes–nucleant combinations since it had a minimal colligative impact on freezing and is relevant for activating cloud droplets. Other nucleators, for instance a silica gel, are unaffected by these ‘solute effects’, to within experimental uncertainty. This split in response to the presence of solutes indicates that different mechanisms of ice nucleation occur on the different nucleators or that surface modification of relevance to ice nucleation proceeds in different ways for different nucleators. These solute effects on immersion mode ice nucleation may be of importance in the atmosphere as sea salt and ammonium sulphate are common cloud condensation nuclei (CCN) for cloud droplets and are internally mixed with ice-nucleating particles in mixed-phase clouds. In addition, we propose a pathway dependence where activation of CCN at low temperatures might lead to enhanced ice formation relative to pathways where CCN activation occurs at higher temperatures prior to cooling to nucleation temperature. PMID:29780544

Neural correlations enable invariant coding and perception of natural stimuli in weakly electric fish

PubMed Central

Metzen, Michael G; Hofmann, Volker; Chacron, Maurice J

2016-01-01

Neural representations of behaviorally relevant stimulus features displaying invariance with respect to different contexts are essential for perception. However, the mechanisms mediating their emergence and subsequent refinement remain poorly understood in general. Here, we demonstrate that correlated neural activity allows for the emergence of an invariant representation of natural communication stimuli that is further refined across successive stages of processing in the weakly electric fish Apteronotus leptorhynchus. Importantly, different patterns of input resulting from the same natural communication stimulus occurring in different contexts all gave rise to similar behavioral responses. Our results thus reveal how a generic neural circuit performs an elegant computation that mediates the emergence and refinement of an invariant neural representation of natural stimuli that most likely constitutes a neural correlate of perception. DOI: http://dx.doi.org/10.7554/eLife.12993.001 PMID:27128376

Psychological Well-being in Fathers of Adolescents and Young Adults with Down Syndrome, Fragile X Syndrome, and Autism.

PubMed

Hartley, Sigan L; Seltzer, Marsha Mailick; Head, Lara; Abbeduto, Leonard

2012-04-01

The psychological well-being of fathers of children with developmental disabilities remains poorly understood. The present study examined depressive symptoms, pessimism, and coping in fathers of adolescents and young adults with Down syndrome (DS; n = 59), autism spectrum disorders (ASDs; n = 135), and fragile X syndrome (FXS; n = 46) Fathers of sons/daughters with ASDs reported a higher level of depressive symptoms than the other groups of fathers. Fathers of sons/daughters with DS reported a lower level of pessimism than the other groups of fathers. There were no group differences in paternal coping style. Group differences in paternal depressive symptoms and pessimism were, in part, related to differences in paternal age, the child's behavior problems, risk of having additional children with a disability, and maternal depressive symptoms. Findings from this study can be used to educate providers and design services for fathers during the later parenting years.

Effect of selenium nanoparticles with different sizes in primary cultured intestinal epithelial cells of crucian carp, Carassius auratus gibelio.

PubMed

Wang, Yanbo; Yan, Xuxia; Fu, Linglin

2013-01-01

Nano-selenium (Se), with its high bioavailability and low toxicity, has attracted wide attention for its potential application in the prevention of oxidative damage in animal tissues. However, the effect of nano-Se of different sizes on the intestinal epithelial cells of the crucian carp (Carassius auratus gibelio) is poorly understood. Our study showed that different sizes and doses of nano-Se have varied effects on the cellular protein contents and the enzyme activities of secreted lactate dehydrogenase, intracellular sodium potassium adenosine triphosphatase, glutathione peroxidase, and superoxide dismutase. It was also indicated that nano-Se had a size-dependent effect on the primary intestinal epithelial cells of the crucian carp. Thus, these findings may bring us a step closer to understanding the size effect and the bioavailability of nano-Se on the intestinal tract of the crucian carp.

Effect of selenium nanoparticles with different sizes in primary cultured intestinal epithelial cells of crucian carp, Carassius auratus gibelio

PubMed Central

Wang, Yanbo; Yan, Xuxia; Fu, Linglin

2013-01-01

Nano-selenium (Se), with its high bioavailability and low toxicity, has attracted wide attention for its potential application in the prevention of oxidative damage in animal tissues. However, the effect of nano-Se of different sizes on the intestinal epithelial cells of the crucian carp (Carassius auratus gibelio) is poorly understood. Our study showed that different sizes and doses of nano-Se have varied effects on the cellular protein contents and the enzyme activities of secreted lactate dehydrogenase, intracellular sodium potassium adenosine triphosphatase, glutathione peroxidase, and superoxide dismutase. It was also indicated that nano-Se had a size-dependent effect on the primary intestinal epithelial cells of the crucian carp. Thus, these findings may bring us a step closer to understanding the size effect and the bioavailability of nano-Se on the intestinal tract of the crucian carp. PMID:24204137

Wide distribution of virulence genes among Enterococcus faecium and Enterococcus faecalis clinical isolates.

PubMed

Soheili, Sara; Ghafourian, Sobhan; Sekawi, Zamberi; Neela, Vasanthakumari; Sadeghifard, Nourkhoda; Ramli, Ramliza; Hamat, Rukman Awang

2014-01-01

Enterococcus, a Gram-positive facultative anaerobic cocci belonging to the lactic acid bacteria of the phylum Firmicutes, is known to be able to resist a wide range of hostile conditions such as different pH levels, high concentration of NaCl (6.5%), and the extended temperatures between 5(°)C and 65(°)C. Despite being the third most common nosocomial pathogen, our understanding on its virulence factors is still poorly understood. The current study was aimed to determine the prevalence of different virulence genes in Enterococcus faecalis and Enterococcus faecium. For this purpose, 79 clinical isolates of Malaysian enterococci were evaluated for the presence of virulence genes. pilB, fms8, efaAfm, and sgrA genes are prevalent in all clinical isolates. In conclusion, the pathogenicity of E. faecalis and E. faecium could be associated with different virulence factors and these genes are widely distributed among the enterococcal species.

Wide Distribution of Virulence Genes among Enterococcus faecium and Enterococcus faecalis Clinical Isolates

PubMed Central

Soheili, Sara; Ghafourian, Sobhan; Sekawi, Zamberi; Neela, Vasanthakumari; Sadeghifard, Nourkhoda; Ramli, Ramliza; Hamat, Rukman Awang

2014-01-01

Enterococcus, a Gram-positive facultative anaerobic cocci belonging to the lactic acid bacteria of the phylum Firmicutes, is known to be able to resist a wide range of hostile conditions such as different pH levels, high concentration of NaCl (6.5%), and the extended temperatures between 5°C and 65°C. Despite being the third most common nosocomial pathogen, our understanding on its virulence factors is still poorly understood. The current study was aimed to determine the prevalence of different virulence genes in Enterococcus faecalis and Enterococcus faecium. For this purpose, 79 clinical isolates of Malaysian enterococci were evaluated for the presence of virulence genes. pilB, fms8, efaAfm, and sgrA genes are prevalent in all clinical isolates. In conclusion, the pathogenicity of E. faecalis and E. faecium could be associated with different virulence factors and these genes are widely distributed among the enterococcal species. PMID:25147855

Testosterone-mediated sex differences in the face shape during adolescence: subjective impressions and objective features.

PubMed

Marečková, Klára; Weinbrand, Zohar; Chakravarty, M Mallar; Lawrence, Claire; Aleong, Rosanne; Leonard, Gabriel; Perron, Michel; Pike, G Bruce; Richer, Louis; Veillette, Suzanne; Pausova, Zdenka; Paus, Tomáš

2011-11-01

Sex identification of a face is essential for social cognition. Still, perceptual cues indicating the sex of a face, and mechanisms underlying their development, remain poorly understood. Previously, our group described objective age- and sex-related differences in faces of healthy male and female adolescents (12-18 years of age), as derived from magnetic resonance images (MRIs) of the adolescents' heads. In this study, we presented these adolescent faces to 60 female raters to determine which facial features most reliably predicted subjective sex identification. Identification accuracy correlated highly with specific MRI-derived facial features (e.g. broader forehead, chin, jaw, and nose). Facial features that most reliably cued male identity were associated with plasma levels of testosterone (above and beyond age). Perceptible sex differences in face shape are thus associated with specific facial features whose emergence may be, in part, driven by testosterone. Copyright © 2011 Elsevier Inc. All rights reserved.

Substrate specificity of the ubiquitin and Ubl proteases

PubMed Central

Ronau, Judith A; Beckmann, John F; Hochstrasser, Mark

2016-01-01

Conjugation and deconjugation of ubiquitin and ubiquitin-like proteins (Ubls) to cellular proteins are highly regulated processes integral to cellular homeostasis. Most often, the C-termini of these small polypeptides are attached to lysine side chains of target proteins by an amide (isopeptide) linkage. Deubiquitinating enzymes (DUBs) and Ubl-specific proteases (ULPs) comprise a diverse group of proteases that recognize and remove ubiquitin and Ubls from their substrates. How DUBs and ULPs distinguish among different modifiers, or different polymeric forms of these modifiers, remains poorly understood. The specificity of ubiquitin/Ubl-deconjugating enzymes for particular substrates depends on multiple factors, ranging from the topography of specific substrate features, as in different polyubiquitin chain types, to structural elements unique to each enzyme. Here we summarize recent structural and biochemical studies that provide insights into mechanisms of substrate specificity among various DUBs and ULPs. We also discuss the unexpected specificities of non-eukaryotic proteases in these families. PMID:27012468

A Physiologically-Based Pharmacokinetic (PBPK) Model With Metabolic Interactions of Chloroform (CHCL3) and Trichloroethylene

EPA Science Inventory

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...

Advanced Pavement Design: Finite Element Modeling for Rigid Pavement Joints, Report II: Model Development

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...

Integrating Demographic, Clinical,and Environmental Exposure Information to Identify Genomic Biomarkers Associated With Subtypes of Childhood Asthma

EPA Science Inventory

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

EPA Science Inventory

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...

Interdependence of endomembrane trafficking and actin dynamics during polarized growth of Arabidopsis pollen tubes

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...

Evaluating the relationship between the driver and roadway to address rural intersection safety using the SHRP 2 naturalistic driving study data.

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...

Gastrointestinal toxicity, systemic inflammation, and liver biochemistry in allogeneic hematopoietic stem cell transplantation

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

EPA Science Inventory

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…

Association between fertilizer-mediated changes in microbial communities and Aedes albopictus growth and survival

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, ...

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

Treesearch

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

EPA Science Inventory

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

Treesearch

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)...

PHOTOSYNTHETIC RESPONSES OF VALLISNERIA AMERICANA FOLLOWING EXPOSURE TO ATRAZINE AT THREE NUTRIENT REGIMES

EPA Science Inventory

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

Treesearch

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

EPA Science Inventory

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

EPA Science Inventory

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...

Identification of a Pathway for Perfluorocompounds to Human Diet from Application of Biosolids to Agricultural Fields

EPA Science Inventory

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...

Sex-related differences in stress tolerance in dioecious plants: a critical appraisal in a physiological context.

PubMed

Juvany, Marta; Munné-Bosch, Sergi

2015-10-01

Sex-related differences in reproductive effort can lead to differences in vegetative growth and stress tolerance. However, do all dioecious plants show sex-related differences in stress tolerance? To what extent can the environmental context and modularity mask sex-related differences in stress tolerance? Finally, to what extent can physiological measurements help us understand secondary sexual dimorphism? This opinion paper aims to answer these three basic questions with special emphasis on developments in research in this area over the last decade. Compelling evidence indicates that dimorphic species do not always show differences in stress tolerance between sexes; and when sex-related differences do occur, they seem to be highly species-specific, with greater stress tolerance in females than males in some species, and the opposite in others. The causes of such sex-related species-specific differences are still poorly understood, and more physiological studies and diversity of plant species that allow comparative analyses are needed. Furthermore, studies performed thus far demonstrate that the expression of dioecy can lead to sex-related differences in physiological traits-from leaf gas exchange to gene expression-but the biological significance of modularity and sectoriality governing such differences has been poorly investigated. Future studies that consider the importance of modularity and sectoriality are essential for unravelling the mechanisms underlying stress adaptation in male and female plants growing in their natural habitat. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Diversity and Ecology of Viruses in Hyperarid Desert Soils

PubMed Central

Zablocki, Olivier; Adriaenssens, Evelien M.

2015-01-01

In recent years, remarkable progress has been made in the field of virus environmental ecology. In marine ecosystems, for example, viruses are now thought to play pivotal roles in the biogeochemical cycling of nutrients and to be mediators of microbial evolution through horizontal gene transfer. The diversity and ecology of viruses in soils are poorly understood, but evidence supports the view that the diversity and ecology of viruses in soils differ substantially from those in aquatic systems. Desert biomes cover ∼33% of global land masses, and yet the diversity and roles of viruses in these dominant ecosystems remain poorly understood. There is evidence that hot hyperarid desert soils are characterized by high levels of bacterial lysogens and low extracellular virus counts. In contrast, cold desert soils contain high extracellular virus titers. We suggest that the prevalence of microbial biofilms in hyperarid soils, combined with extreme thermal regimens, exerts strong selection pressures on both temperate and virulent viruses. Many desert soil virus sequences show low values of identity to virus genomes in public databases, suggesting the existence of distinct and as-yet-uncharacterized soil phylogenetic lineages (e.g., cyanophages). We strongly advocate for amplification-free metavirome analyses while encouraging the classical isolation of phages from dominant and culturable microbial isolates in order to populate sequence databases. This review provides an overview of recent advances in the study of viruses in hyperarid soils and of the factors that contribute to viral abundance and diversity in hot and cold deserts and offers technical recommendations for future studies. PMID:26590289

Lags in the response of mountain plant communities to climate change.

PubMed

Alexander, Jake M; Chalmandrier, Loïc; Lenoir, Jonathan; Burgess, Treena I; Essl, Franz; Haider, Sylvia; Kueffer, Christoph; McDougall, Keith; Milbau, Ann; Nuñez, Martin A; Pauchard, Aníbal; Rabitsch, Wolfgang; Rew, Lisa J; Sanders, Nathan J; Pellissier, Loïc

2018-02-01

Rapid climatic changes and increasing human influence at high elevations around the world will have profound impacts on mountain biodiversity. However, forecasts from statistical models (e.g. species distribution models) rarely consider that plant community changes could substantially lag behind climatic changes, hindering our ability to make temporally realistic projections for the coming century. Indeed, the magnitudes of lags, and the relative importance of the different factors giving rise to them, remain poorly understood. We review evidence for three types of lag: "dispersal lags" affecting plant species' spread along elevational gradients, "establishment lags" following their arrival in recipient communities, and "extinction lags" of resident species. Variation in lags is explained by variation among species in physiological and demographic responses, by effects of altered biotic interactions, and by aspects of the physical environment. Of these, altered biotic interactions could contribute substantially to establishment and extinction lags, yet impacts of biotic interactions on range dynamics are poorly understood. We develop a mechanistic community model to illustrate how species turnover in future communities might lag behind simple expectations based on species' range shifts with unlimited dispersal. The model shows a combined contribution of altered biotic interactions and dispersal lags to plant community turnover along an elevational gradient following climate warming. Our review and simulation support the view that accounting for disequilibrium range dynamics will be essential for realistic forecasts of patterns of biodiversity under climate change, with implications for the conservation of mountain species and the ecosystem functions they provide. © 2017 John Wiley & Sons Ltd.

Diagnosis and management of heart failure in the fetus

PubMed Central

DAVEY, B.; SZWAST, A.; RYCHIK, J.

2015-01-01

Heart failure can be defined as the inability of the heart to sufficiently support the circulation. In the fetus, heart failure can be caused by a myriad of factors that include fetal shunting abnormalities, genetic cardiomyopathies, extracardiac malformations, arrhythmias and structural congenital heart disease. With advances in ultrasound has come the ability to characterize many complex conditions, previously poorly understood. Fetal echocardiography provides the tools necessary to evaluate and understand the various physiologies that contribute to heart failure in the fetus. In this review, we will explore the different mechanisms of heart failure in this unique patient population and highlight the role of fetal echocardiography in the current management of these conditions PMID:22992530

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatakeyama, Hiroto; Wu, Sherry Y.; Lyons, Yasmin A.

Even though hyperthermia is a promising treatment for cancer, the relationship between specific temperatures and clinical benefits and predictors of sensitivity of cancer to hyperthermia is poorly understood. Ovarian and uterine tumors have diverse hyperthermia sensitivities. Integrative analyses of the specific gene signatures and the differences in response to hyperthermia between hyperthermia-sensitive and -resistant cancer cells identified CTGF as a key regulator of sensitivity. CTGF silencing sensitized resistant cells to hyperthermia. CTGF small interfering RNA (siRNA) treatment also sensitized resistant cancers to localized hyperthermia induced by copper sulfide nanoparticles and near-infrared laser in orthotopic ovarian cancer models. Lastly, CTGF silencingmore » aggravated energy stress induced by hyperthermia and enhanced apoptosis of hyperthermia-resistant cancers.« less

Women and men with intellectual disabilities who sell or trade sex: voices from the professionals.

PubMed

Kuosmanen, Jari; Starke, Mikaela

2011-01-01

The phenomenon of women and men with intellectual disabilities (ID) selling or exchanging sexual services is poorly understood. In this study, the authors explored the knowledge and perceptions of this phenomenon shared by professionals working in the field. Focus group discussions demonstrated broad familiarity with the phenomenon. Different motives and contributing factors were identified for the behavior, blurring the boundary line between free choice and exploitation. Two distinct discourses emerged from the interviews based on the assumed "rationality" of the sex transaction and its rewards: Those with ID who traded sexual favors were presented as either conscious and autonomous agents or unaware and exploited victims.

Vital effects in coral skeletal composition display strict three-dimensional control

USGS Publications Warehouse

Meibom, A.; Yurimoto, H.; Cuif, J.-P.; Domart-Coulon, I.; Houlbreque, F.; Constantz, B.; Dauphin, Y.; Tambutte, E.; Tambutte, S.; Allemand, D.; Wooden, J.; Dunbar, R.

2006-01-01

Biological control over coral skeletal composition is poorly understood but critically important to paleoenvironmental reconstructions. We present microanalytical measurements of trace-element abundances as well as oxygen and carbon isotopic compositions of individual skeletal components in the zooxanthellate coral Colpophyllia sp. Our data show that centers of calcification (COC) have higher trace element concentrations and distinctly lighter isotopic compositions than the fibrous components of the skeleton. These observations necessitate that COC and the fibrous skeleton are precipitated by different mechanisms, which are controlled by specialized domains of the calicoblastic cell-layer. Biological processes control the composition of the skeleton even at the ultra-structure level. Copyright 2006 by the American Geophysical Union.

Exercising arrhythmias and sudden cardiac death in horses: Review of the literature and comparative aspects.

PubMed

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.

Pivotal response treatment prompts a functional rewiring of the brain among individuals with autism spectrum disorder.

PubMed

Venkataraman, Archana; Yang, Daniel Y-J; Dvornek, Nicha; Staib, Lawrence H; Duncan, James S; Pelphrey, Kevin A; Ventola, Pamela

2016-09-28

Behavioral interventions for autism have gained prominence in recent years; however, the neural-systems-level targets of these interventions remain poorly understood. We use a novel Bayesian framework to extract network-based differences before and after a 16-week pivotal response treatment (PRT) regimen. Our results suggest that the functional changes induced by PRT localize to the posterior cingulate and are marked by a shift in connectivity from the orbitofrontal cortex to the occipital-temporal cortex. Our results illuminate a potential PRT-induced learning mechanism, whereby the neural circuits involved during social perception shift from sensory and attentional systems to higher-level object and face processing areas.

Pivotal Response Treatment Prompts a Functional Rewiring of the Brain amongst Individuals with Autism Spectrum Disorder

PubMed Central

Venkataraman, Archana; Yang, Daniel Y.-J.; Dvornek, Nicha; Staib, Lawrence H.; Duncan, James S.; Pelphrey, Kevin A.; Ventola, Pamela

2016-01-01

Behavioral interventions for autism have gained prominence in recent years; however, the neural-systems-level targets of these interventions remain poorly understood. We use a novel Bayesian framework to extract network-based differences before and after a 16-week Pivotal Response Treatment (PRT) regimen. Our results suggest that functional changes induced by PRT localize to the posterior cingulate and are marked by a shift in connectivity from the orbitofrontal cortex to the occipital temporal cortex. Our results illuminate a potential PRT-induced learning mechanism, whereby the neural circuits involved during social perception shift from sensory and attentional systems to higher-level object and face processing areas. PMID:27532879

Surface enhanced Raman scattering on Tardigrada--towards monitoring and imaging molecular structures in live cryptobiotic organisms.

PubMed

Kneipp, Harald; Møbjerg, Nadja; Jørgensen, Aslak; Bohr, Henrik G; Hélix-Nielsen, Claus; Kneipp, Janina; Kneipp, Katrin

2013-10-01

Tardigrades are microscopic metazoans which are able to survive extreme physical and chemical conditions by entering a stress tolerant state called cryptobiosis. At present, the molecular mechanisms behind cryptobiosis are still poorly understood. We show that surface enhanced Raman scattering supported by plasmonic gold nanoparticles can measure molecular constituents and their local distribution in live tardigrades. Surface enhanced Raman signatures allow to differentiate between two species and indicate molecular structural differences between tardigrades in water and in a dry state. This opens new avenues for exploring cryptobiosis by studying molecular changes in live cryptobiotic organisms. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Osteoarthritis of the distal interphalangeal joint.

PubMed

Kaufmann, Robert A; Lögters, Tim T; Verbruggen, Gust; Windolf, Joachim; Goitz, Robert J

2010-12-01

Osteoarthritis occurs with the highest prevalence in the distal interphalangeal joint of the hand and has been divided into an erosive and a nonerosive form. The pathogenesis of the early stages of osteoarthritis is poorly understood, but considerable emphasis has been placed on the role of cartilage and subchondral bone as well as soft tissue structures such as collateral ligaments and tendons. Radiographic evaluation represents the most standardized method to quantify disease progression, with different systems having been developed for defining and grading radiographic features. This current concepts article examines the recent knowledge base regarding the etiology, pathogenesis, and evaluation of osteoarthritis of the distal interphalangeal joint. Copyright © 2010. Published by Elsevier Inc.

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

Non-convulsive seizures and electroencephalography findings as predictors of clinical outcomes at a tertiary intensive care unit in Saudi Arabia.

PubMed

Al-Said, Youssef A; Baeesa, Saleh S; Shivji, Zaitoon; Kayyali, Husam; Alqadi, Khalid; Kadi, Ghada; Cupler, Edward J; Abuzinadah, Ahmad R

2018-06-05

Electroencephalography (EEG) in the intensive care unit (ICU) is often done to detect non-convulsive seizures (NCS). The outcome of ICU patients with NCS strongly depends on the underlying etiology. The implication of NCS and other EEG findings on clinical outcome independent from their etiology is not well understood and our aim to investigate it. We retrospectively identified all adult patients in the ICU who underwent EEG monitoring between January 2008 and December 2011. The main goals were to define the rate of NCS or non-convulsive status epilepticus (NCSE) occurrence in our center among patients who underwent EEG monitoring and to examine if NCS/NCSE are associated with poor outcome [defined as death or dependence] with and without adjustment for underlying etiology. The rate of poor outcome among different EEG categories were also investigated. During the study period, 177 patients underwent EEG monitoring in our ICU. The overall outcome was poor in 62.7% of those undergoing EEG. The rate of occurrence of NCS/NCSE was 8.5% and was associated with poor outcome in 86.7% with an odds ratio (OR) of 5.1 (95% confidence interval [CI] 1.09-23.8). This association was maintained after adjusting for underlying etiologies with OR 5.6 (95% CI 1.05-29.6). The rate of poor outcome was high in the presence of periodic discharges and sharp and slow waves of 75% and 61.5%, respectively. Our cohort of ICU patients undergoing EEGs had a poor outcome. Those who developed NCS/NCSE experienced an even worse outcome regardless of the underlying etiology. Copyright © 2018 Elsevier B.V. All rights reserved.

Sexual differences in food preferences in the white stork: an experimental study

NASA Astrophysics Data System (ADS)

Kwieciński, Zbigniew; Rosin, Zuzanna M.; Dylewski, Łukasz; Skórka, Piotr

2017-06-01

Sex differences in the foraging ecology of monomorphic species are poorly understood, due to problems with gender identification in field studies. In the current study, we used experimental conditions to investigate the food preferences of the white stork Ciconia ciconia, an opportunistic species in terms of food, but characterised by a low level of sexual dimorphism. During a 10-day experiment, 29 individuals (20 females and 9 males) were studied by means of a `cafeteria test' in which the storks' diet consisted of mammals, birds, fish, amphibians, insects and earthworms. The storks preferred food characterised by high calorific and protein values such as mammals, birds and fish. Sexes differed strongly in their preferences; males preferred mammals, whereas females preferred birds. Moreover, females consumed insects and earthworms less often than males. Interestingly, males spent significantly less time foraging than females. We have demonstrated that the white stork exhibits clear sexual differences in food preferences which are mostly attributable to differences in parental duties, physiology and anatomy.

A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment

PubMed Central

van der Heijden, Marcel GA; Bruin, Susanne de; Luckerhoff, Ludo; van Logtestijn, Richard SP; Schlaeppi, Klaus

2016-01-01

Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions. PMID:26172208

Evidence synthesis and its role in evidence-based health care.

PubMed

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.

Associations of a Short Sleep Duration, Insufficient Sleep, and Insomnia with Self-Rated Health among Nurses.

PubMed

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.

Biogeographical disparity in the functional diversity and redundancy of corals.

PubMed

McWilliam, Mike; Hoogenboom, Mia O; Baird, Andrew H; Kuo, Chao-Yang; Madin, Joshua S; Hughes, Terry P

2018-03-20

Corals are major contributors to a range of key ecosystem functions on tropical reefs, including calcification, photosynthesis, nutrient cycling, and the provision of habitat structure. The abundance of corals is declining at multiple scales, and the species composition of assemblages is responding to escalating human pressures, including anthropogenic global warming. An urgent challenge is to understand the functional consequences of these shifts in abundance and composition in different biogeographical contexts. While global patterns of coral species richness are well known, the biogeography of coral functions in provinces and domains with high and low redundancy is poorly understood. Here, we quantify the functional traits of all currently recognized zooxanthellate coral species ( n = 821) in both the Indo-Pacific and Atlantic domains to examine the relationships between species richness and the diversity and redundancy of functional trait space. We find that trait diversity is remarkably conserved (>75% of the global total) along latitudinal and longitudinal gradients in species richness, falling away only in species-poor provinces ( n < 200), such as the Persian Gulf (52% of the global total), Hawaii (37%), the Caribbean (26%), and the East-Pacific (20%), where redundancy is also diminished. In the more species-poor provinces, large and ecologically important areas of trait space are empty, or occupied by just a few, highly distinctive species. These striking biogeographical differences in redundancy could affect the resilience of critical reef functions and highlight the vulnerability of relatively depauperate, peripheral locations, which are often a low priority for targeted conservation efforts.

Reduction of rainbow trout spleen size by splenectomy does not alter resistance against bacterial cold water disease

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...

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

EPA Science Inventory

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 ...

Students' Perspective into the Apathy and Social Disconnectedness They Feel in Undergraduate Business Classrooms

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…

Fishing for Features

ScienceCinema

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.

INFILTRATION THROUGH DISTURBED URBAN SOILS AND COMPOST-AMENDED SOIL EFFECTS OF RUNOFF QUALITY AND QUANTITY

EPA Science Inventory

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

Treesearch

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...

A small cysteine-rich protein from the Asian soybean rust fungus, Phakopsora pachyrhizi, suppresses plant immunity

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…

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

EPA Science Inventory

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...

Associations among plasma metabolite levels and short-term exposure to PM2.5 and ozone in a cardiac catheterization cohort.

EPA Science Inventory

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,…

Effort versus reward: preparing samples for fungal community characterization in high-throughput sequencing surveys of soils

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...

Size matters: The contribution of mega-infauna to the food webs and ecosystem services of an Oregon estuary - 9-30-12

EPA Science Inventory

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...

Cotton defense induction patterns under spatially, temporally and quantitatively varying herbivory levels

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

Treesearch

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...

CARRY-OVER EFFECTS OF OZONE ON ROOT GROWTH AND CARBOHYDRATE CONCENTRATIONS OF PONDEROSA PINE SEEDLINGS

EPA Science Inventory

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...

Exposure for ultrafine carbon particles at levels below detectable pulmonary inflammation affects cardiovascular performance in spontaneously hypertensive rats*

EPA Science Inventory

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...

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....

PERCHLOROETHYLENE (PERC) INHIBITS FUNCTION OF VOLTAGE-GATED CALCIUM CHANNELS IN PHEOCHROMOCYTOMA CELLS.

EPA Science Inventory

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...

RNAi-mediated down-regulation of a melanin polyketide synthase (pks1) gene in the fungus Slafractonia leguminicola

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 ...

Fishing for Features

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…

AGING AND LIFE-STAGE SUSCEPTIBILITY: TOLUENE EFFECTS ON BRAIN OXIDATIVE STRESS PARAMETERS IN BROWN NORWAY RATS.

EPA Science Inventory

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…

Adaptation of neuronal signaling and cell stress response pathways in a multigenic response of Drosophila melanogaster to DDT selection

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...

Life cycle expression analysis of three cell wall degradation-related genes in ethylene-treated grass

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...

Deficit irrigation practices may alter Vitis vinifera L. resistance to cold injury: Empirical evidence from the field

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 aerosol formation from fossil fuel sources contribute majority of summertime organic mass at Bakersfield

EPA Science Inventory

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…

Exposure to pairs of Aeromonas strains enhances virulence in the Caenorhabditis elegans infection model

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,...

Rehabilitation Counseling Professional Associations: Membership, Membership Intentions, and Levels of Commitment among Rehabilitation Counseling Professionals

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.

Treesearch

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?

EPA Science Inventory

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...

Vegetative biomass predicts inflorescence production along a CO2 concentration gradient in mesic grassland

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

Treesearch

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,...

Short-term Effects of Air Temperature on Blood Markers of Coagulation and Inflammation in Potentially Susceptible Individuals

EPA Science Inventory

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...

Cardiomyopathy confers susceptibility to particulate matter-induced oxidative stress, vagal dominance, arrhythmia, pulmonary inflammation in heart failure-prone rats

EPA Science Inventory

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…

Regulating Approaches to Learning: Testing Learning Strategy Convergences across a Year at University

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…

Spatial vegetation patterns and neighborhood competition among woody plants in an East African savanna

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…

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…

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

Treesearch

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....

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...

Dissecting genome-wide association signals for loss-of-function phenotypes in sorghum flavonoid pigmentation traits

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...

Single Particulate SEM-EDX Analysis of Iron-Containing Coarse Particulate Matter in an Urban Environment: Sources and Distribution of Iron within Cleveland, Ohio

EPA Science Inventory

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…

Flexibility and extracellular opening determine the interaction between ligands and insect sulfakinin receptors

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 ...

Acute and Subchronic Toxicity of Inhaled Toluene in Male Long-Evans Rats: Oxidative Stress Markers in Brain

EPA Science Inventory

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

EPA Science Inventory

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,…

Changes in Markers of Genotoxicity in Relation to Exposure to Disinfection By-Products in Swimming Pools

EPA Science Inventory

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...

Understanding the carotenoid biosynthetic pathway through observation of four color variants of developing watermelon (Citrullus lanatus (Thunb.) Matsum. & Nanai)

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 ...

A COMPUTER-CONTROLLED SYSTEM FOR GENERATING UNIFORM SURFACE DEPOSITS TO STUDY THE TRANSPORT OF PARTICULATE MATTER

EPA Science Inventory

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...

Luminal Starch Substrate "Brake" on Maltase-Glucoamylase Activity Is Located within the Glucoamylase Subunit

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

EPA Science Inventory

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...

Synergism between inositol polyphosphates and TOR kinase signaling in nutrient sensing, growth control, and lipid metabolism in Chlamydomonas

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

EPA Science Inventory

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…

Transcriptional markers of sub-optimal nutrition in developing Apis mellifera nurse workers

PubMed Central

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

Low Cognitive Impulsivity Is Associated with Better Gain and Loss Learning in a Probabilistic Decision-Making Task

PubMed Central

Cáceres, Pablo; San Martín, René

2017-01-01

Many advances have been made over the last decades in describing, on the one hand, the link between reward-based learning and decision-making, and on the other hand, the link between impulsivity and decision-making. However, the association between reward-based learning and impulsivity remains poorly understood. In this study, we evaluated the association between individual differences in loss-minimizing and gain-maximizing behavior in a learning-based probabilistic decision-making task and individual differences in cognitive impulsivity. We found that low cognitive impulsivity was associated both with a better performance minimizing losses and maximizing gains during the task. These associations remained significant after controlling for mathematical skills and gender as potential confounders. We discuss potential mechanisms through which cognitive impulsivity might interact with reward-based learning and decision-making. PMID:28261137

Low Cognitive Impulsivity Is Associated with Better Gain and Loss Learning in a Probabilistic Decision-Making Task.

PubMed

Cáceres, Pablo; San Martín, René

2017-01-01

Many advances have been made over the last decades in describing, on the one hand, the link between reward-based learning and decision-making, and on the other hand, the link between impulsivity and decision-making. However, the association between reward-based learning and impulsivity remains poorly understood. In this study, we evaluated the association between individual differences in loss-minimizing and gain-maximizing behavior in a learning-based probabilistic decision-making task and individual differences in cognitive impulsivity. We found that low cognitive impulsivity was associated both with a better performance minimizing losses and maximizing gains during the task. These associations remained significant after controlling for mathematical skills and gender as potential confounders. We discuss potential mechanisms through which cognitive impulsivity might interact with reward-based learning and decision-making.

Developmental differences in auditory detection and localization of approaching vehicles.

PubMed

Barton, Benjamin K; Lew, Roger; Kovesdi, Casey; Cottrell, Nicholas D; Ulrich, Thomas

2013-04-01

Pedestrian safety is a significant problem in the United States, with thousands being injured each year. Multiple risk factors exist, but one poorly understood factor is pedestrians' ability to attend to vehicles using auditory cues. Auditory information in the pedestrian setting is increasing in importance with the growing number of quieter hybrid and all-electric vehicles on America's roadways that do not emit sound cues pedestrians expect from an approaching vehicle. Our study explored developmental differences in pedestrians' detection and localization of approaching vehicles. Fifty children ages 6-9 years, and 35 adults participated. Participants' performance varied significantly by age, and with increasing speed and direction of the vehicle's approach. Results underscore the importance of understanding children's and adults' use of auditory cues for pedestrian safety and highlight the need for further research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Organic Analysis in Miller Range 090657 and Buckley Island 10933 CR2 Chondrites: Part 1 In-Situ Observation of Carbonaceous Material

NASA Technical Reports Server (NTRS)

Cao, T.; Nakamura-Messenger, K.; Berger, E. L.; Burton, A. S.; Messenger, S.; Clemett, S. J.

2016-01-01

Primitive carbonaceous chondrites contain a wide variety of organic material, ranging from soluble discrete molecules to insoluble unstructured kerogen-like component as well as structured nano-globules of macromolecular carbon. The relationship between the soluble organic molecules, macromolecular organic material, and host minerals are poorly understood. Due to the differences in extractability of soluble and insoluble organic materials, the analysis methods for each differ and are often performed independently. The combination of soluble and insoluble analyses, when performed concurrently, can provide a wider understanding on spatial distribution, and elemental, structural and isotopic composition of organic material in primitive meteorites. Furthermore, they can provide broader perspective on how extraterrestrial organic ma-terials potentially contributed to the synthesis of life's essential compounds such as amino acids, sugar acids, activated phosphates and nucleobases.

Using photometrically selected metal-poor stars to study dwarf galaxies and the Galactic stellar halo

NASA Astrophysics Data System (ADS)

Youakim, Kris; Starkenburg, Else; Martin, Nicolas; Pristine Team

2018-06-01

The Pristine survey is a narrow-band photometric survey designed to efficiently search for extremely metal-poor (EMP) stars. In the first three years of the survey, it has demonstrated great efficiency at finding EMP stars, and also great promise for increasing the current, small sample of the most metal-poor stars. The present sky coverage is ~2500 square degrees in the Northern Galactic Halo, including several individual fields targeting dwarf galaxies. By efficiently identifying member stars in the outskirts of known faint dwarf galaxies, the dynamical histories and chemical abundance patterns of these systems can be understood in greater detail. Additionally, with reliable photometric metallicities over a large sky coverage it is possible to perform a large scale clustering analysis in the Milky Way halo, and investigate the characteristic scale of substructure at different metallicities. This can reveal important details about the process of building up the halo through dwarf galaxy accretion, and offer insight into the connection between dwarf galaxies and the Milky Way halo. In this talk I will outline our results on the search for the most pristine stars, with a focus on how we are using this information to advance our understanding of dwarf galaxies and their contribution to the formation of the Galactic stellar halo.

Desiccation stress and tolerance in green algae: consequences for ultrastructure, physiological and molecular mechanisms

PubMed Central

Holzinger, Andreas; Karsten, Ulf

2013-01-01

Although most green algae typically occur in aquatic ecosystems, many species also live partly or permanently under aeroterrestrial conditions, where the cells are exposed to the atmosphere and hence regularly experience dehydration. The ability of algal cells to survive in an air-dried state is termed desiccation tolerance. The mechanisms involved in desiccation tolerance of green algae are still poorly understood, and hence the aim of this review is to summarize recent findings on the effects of desiccation and osmotic water loss. Starting from structural changes, physiological, and biochemical consequences of desiccation will be addressed in different green-algal lineages. The available data clearly indicate a range of strategies, which are rather different in streptophycean and non-streptophycean green algae. While members of the Trebouxiophyceae exhibit effective water loss-prevention mechanisms based on the biosynthesis and accumulation of particular organic osmolytes such as polyols, these compounds are so far not reported in representatives of the Streptophyta. In members of the Streptophyta such as Klebsormidium, the most striking observation is the appearance of cross-walls in desiccated samples, which are strongly undulating, suggesting a high degree of mechanical flexibility. This aids in maintaining structural integrity in the dried state and allows the cell to maintain turgor pressure for a prolonged period of time during the dehydration process. Physiological strategies in aeroterrestrial green algae generally include a rapid reduction of photosynthesis during desiccation, but also a rather quick recovery after rewetting, whereas aquatic species are sensitive to drying. The underlying mechanisms such as the affected molecular components of the photosynthetic machinery are poorly understood in green algae. Therefore, modern approaches based on transcriptomics, proteomics, and/or metabolomics are urgently needed to better understand the molecular mechanisms involved in desiccation-stress physiology of these organisms. The very limited existing information is described in the present review. PMID:23986769

The neural bases of feeling understood and not understood

PubMed Central

Torre, Jared B.; Eisenberger, Naomi I.

2014-01-01

Past research suggests that feeling understood enhances both personal and social well-being. However, little research has examined the neurobiological bases of feeling understood and not understood. We addressed these gaps by experimentally inducing felt understanding and not understanding as participants underwent functional magnetic resonance imaging. The results demonstrated that feeling understood activated neural regions previously associated with reward and social connection (i.e. ventral striatum and middle insula), while not feeling understood activated neural regions previously associated with negative affect (i.e. anterior insula). Both feeling understood and not feeling understood activated different components of the mentalizing system (feeling understood: precuneus and temporoparietal junction; not feeling understood: dorsomedial prefrontal cortex). Neural responses were associated with subsequent feelings of social connection and disconnection and were modulated by individual differences in rejection sensitivity. Thus, this study provides insight into the psychological processes underlying feeling understood (or not) and may suggest new avenues for targeted interventions that amplify the benefits of feeling understood or buffer individuals from the harmful consequences of not feeling understood. PMID:24396002

The effects of caffeine on the cholinergic system.

PubMed

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.

Brain structure predicts risk for obesity ☆

PubMed Central

Smucny, Jason; Cornier, Marc-Andre; Eichman, Lindsay C.; Thomas, Elizabeth A.; Bechtell, Jamie L.; Tregellas, Jason R.

2014-01-01

The neurobiology of obesity is poorly understood. Here we report findings of a study designed to examine the differences in brain regional gray matter volume in adults recruited as either Obese Prone or Obese Resistant based on self-identification, body mass index, and personal/family weight history. Magnetic resonance imaging was performed in 28 Obese Prone (14 male, 14 female) and 25 Obese Resistant (13 male, 12 female) healthy adults. Voxel-based morphometry was used to identify gray matter volume differences between groups. Gray matter volume was found to be lower in the insula, medial orbitofrontal cortex and cerebellum in Obese Prone, as compared to Obese Resistant individuals. Adjusting for body fat mass did not impact these results. Insula gray matter volume was negatively correlated with leptin concentration and measures of hunger. These findings suggest that individuals at risk for weight gain have structural differences in brain regions known to be important in energy intake regulation, and that these differences, particularly in the insula, may be related to leptin. PMID:22963736

Reported maternal tendencies predict the reward value of infant facial cuteness, but not cuteness detection

PubMed Central

Hahn, Amanda C.; DeBruine, Lisa M.; Jones, Benedict C.

2015-01-01

The factors that contribute to individual differences in the reward value of cute infant facial characteristics are poorly understood. Here we show that the effect of cuteness on a behavioural measure of the reward value of infant faces is greater among women reporting strong maternal tendencies. By contrast, maternal tendencies did not predict women's subjective ratings of the cuteness of these infant faces. These results show, for the first time, that the reward value of infant facial cuteness is greater among women who report being more interested in interacting with infants, implicating maternal tendencies in individual differences in the reward value of infant cuteness. Moreover, our results indicate that the relationship between maternal tendencies and the reward value of infant facial cuteness is not due to individual differences in women's ability to detect infant cuteness. This latter result suggests that individual differences in the reward value of infant cuteness are not simply a by-product of low-cost, functionless biases in the visual system. PMID:25740842

Her versus his migraine: multiple sex differences in brain function and structure

PubMed Central

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

An empirical analysis of public and private medical practice in Australia.

PubMed

Cheng, Terence C; Joyce, Catherine M; Scott, Anthony

2013-06-01

The combination of public and private medical practice is widespread in many health systems and has important consequences for health care cost and quality. However, its forms and prevalence vary widely and are poorly understood. This paper examines factors associated with public and private sector work by medical specialists using a nationally representative sample of Australian doctors. We find considerable variations in the practice patterns, remuneration contracts and professional arrangements across doctors in different work sectors. Both specialists in mixed practice and private practice differ from public sector specialists with regard to their annual earnings, sources of income, maternity and other leave taken and number of practice locations. Public sector specialists are likely to be younger, to be international medical graduates, devote a higher percentage of time to education and research, and are more likely to do after hours and on-call work compared with private sector specialists. Gender and total hours worked do not differ between doctors across the different practice types. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Bacterial Translocation Ratchets: Shared Physical Principles with Different Molecular Implementations: How bacterial secretion systems bias Brownian motion for efficient translocation of macromolecules.

PubMed

Hepp, Christof; Maier, Berenike

2017-10-01

Secretion systems enable bacteria to import and secrete large macromolecules including DNA and proteins. While most components of these systems have been identified, the molecular mechanisms of macromolecular transport remain poorly understood. Recent findings suggest that various bacterial secretion systems make use of the translocation ratchet mechanism for transporting polymers across the cell envelope. Translocation ratchets are powered by chemical potential differences generated by concentration gradients of ions or molecules that are specific to the respective secretion systems. Bacteria employ these potential differences for biasing Brownian motion of the macromolecules within the conduits of the secretion systems. Candidates for this mechanism include DNA import by the type II secretion/type IV pilus system, DNA export by the type IV secretion system, and protein export by the type I secretion system. Here, we propose that these three secretion systems employ different molecular implementations of the translocation ratchet mechanism. © 2017 The Authors. BioEssays Published by WILEY Periodicals, Inc.

Redox Conditions Affect Ultrafast Exciton Transport in Photosynthetic Pigment-Protein Complexes.

PubMed

Allodi, Marco A; Otto, John P; Sohail, Sara H; Saer, Rafael G; Wood, Ryan E; Rolczynski, Brian S; Massey, Sara C; Ting, Po-Chieh; Blankenship, Robert E; Engel, Gregory S

2018-01-04

Pigment-protein complexes in photosynthetic antennae can suffer oxidative damage from reactive oxygen species generated during solar light harvesting. How the redox environment of a pigment-protein complex affects energy transport on the ultrafast light-harvesting time scale remains poorly understood. Using two-dimensional electronic spectroscopy, we observe differences in femtosecond energy-transfer processes in the Fenna-Matthews-Olson (FMO) antenna complex under different redox conditions. We attribute these differences in the ultrafast dynamics to changes to the system-bath coupling around specific chromophores, and we identify a highly conserved tyrosine/tryptophan chain near the chromophores showing the largest changes. We discuss how the mechanism of tyrosine/tryptophan chain oxidation may contribute to these differences in ultrafast dynamics that can moderate energy transfer to downstream complexes where reactive oxygen species are formed. These results highlight the importance of redox conditions on the ultrafast transport of energy in photosynthesis. Tailoring the redox environment may enable energy transport engineering in synthetic light-harvesting systems.

Her versus his migraine: multiple sex differences in brain function and structure.

PubMed

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.

Feline drug metabolism and disposition: pharmacokinetic evidence for species differences and molecular mechanisms

PubMed Central

2013-01-01

Synopsis Although it is widely appreciated that cats respond differently to certain drugs when compared with other companion animal species, the causes of these differences are poorly understood. This review critically evaluates published evidence for altered drug effects in cats, focusing on pharmacokinetic differences between cats, dogs and humans, and the molecular mechanisms underlying these differences. Pharmacokinetic studies indicate that acetaminophen, propofol, carprofen, and acetylsalicylic acid (aspirin) are cleared significantly more slowly in cats versus dogs and humans. All of these drugs are metabolized by conjugation. Cats lack the major phenol UDP-glucuronosyltransferase (UGT) enzymes, including UGT1A6 and UGT1A9, that glucuronidate acetaminophen and propofol. Deficient glucuronidation may also explain slower carprofen clearance, although there is no direct evidence for this. However, poor aspirin clearance in cats appears to be mainly a consequence of slower glycine conjugation. Cats are also deficient in several other conjugation enzymes, including N-acetyltransferase (NAT) 2 and thiopurine methyltransferase (TMPT). NAT2 deficiency may be the reason cats are more prone to developing methemoglobinemia rather than hepatotoxicity from acetaminophen. TMPT deficiency may predispose cats to azathioprine toxicity. No evidence was found for slower elimination of drugs cleared by oxidation or unchanged into urine or bile. Piroxicam, an oxidized drug, was cleared much more rapidly in cats than humans and dogs, although the mechanism for this difference is unclear. More work is needed to better understand drug metabolism and disposition differences in cats, thereby enabling more rational prescribing of existing medications, and the development of safer drugs for this species. PMID:23890237

Mental health among adolescents living with HIV in Namibia: the role of poverty, orphanhood and social support.

PubMed

Gentz, Shelene G; Calonge-Romano, Isabel; Martínez-Arias, Rosario; Zeng, Chengbo; Ruiz-Casares, Mónica

2018-05-30

The mental health needs of children and adolescents living with HIV (ALHIV) in Namibia are poorly understood, despite the dramatic improvement in their survival. ALHIV in resource poor contexts face particular risk factors, such as poverty, orphanhood, and poor social support. This study examines the mental health of ALHIV in Namibia, and the factors that contribute to mental health problems. A case-control design assessed emotional and behavioural symptoms of distress, risk and protective factors among adolescents aged 12-18 years. Case participants were 99 HIV-positive adolescents. Case controls were 159 adolescents from the same community who were not known to be HIV seropositive at the time of the study. Control group participants were selected from schools using a stratified random sampling. A larger proportion of HIV-positive adolescents were orphaned (62.6% vs. 20.8%, p < .001); the groups showed no differences in poverty factors. HIV-positive adolescents scored lower than the control group on total perceived social support (p < .05) and caregiver support (p < .05), but no differences in perceived friend support and support from a self-selected person were present. HIV-positive adolescents reported significantly more total emotional and behavioural difficulties (p = .027) and conduct problems (p = .025), even after controlling for socio-demographic factors. However, after controlling for the effects of orphanhood, group differences in mental health outcomes were no longer significant. Furthermore, mediation analysis suggested that social support completely mediated the relationship between HIV status and mental health (standardised pathway coefficients = .05, p = .021). Policies and programmes that aim to strengthen social support and take orphanhood status into consideration may improve the mental health of adolescents living with HIV.

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…

Land-use history has a stronger impact on soil microbial community composition than aboveground vegetation and soil properties

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…

Germination and growth of native and invasive plants on soil associated with biological control of Tamarisk (Tamarix spp.)

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?

PubMed

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.

Nitrogen cycling following mountain pine beetle disturbance in lodgepole pine forests of Greater Yellowstone

Treesearch

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...

ANALYTICAL CHEMISTRY RESEARCH NEEDS FOR MAPPING TRENDS OF PHARMACEUTICAL AND PERSONAL CARE PRODUCT POLLUTION FROM PERSONAL USE

EPA Science Inventory

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

Treesearch

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...

Relationship between Nutritional Knowledge and the Amount of Sugar-Sweetened Beverages Consumed in Los Angeles County

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…

Loneliness and Depression among Polish University Students: Preliminary Findings from a Longitudinal Study

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…

Approaches to understanding the impact of life-history features on plant-pathogen co-evolutionary dynamics

Treesearch

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…

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…

PHYTOTOXICITY OF THREE SUBMERGED AQUATIC MACROPHYTE SPECIES TO COPPER AND ATRAZINE UNDER HIGH AND LOW NUTRIENT CONCENTRATIONS

EPA Science Inventory

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...

Paracrine-acting adiponectin promotes mammary epithelial differentiation and synergizes with genistein to enhance transcriptional response to estrogen receptor beta signaling

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

Treesearch

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?

Treesearch

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...

Principles of Cancer Screening.

PubMed

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…

Invasive perennial grasses in Quercus garryana meadows of southwestern British Columbia: prospects for restoration

Treesearch

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

Treesearch

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…

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

Treesearch

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…

Dissecting the Influences of Climate and Demography on the Dynamics of Leptospirosis in California Sea Lions

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...

Early Attachment Organization Moderates the Parent-Child Mutually Coercive Pathway to Children's Antisocial Conduct

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...

Description of microsporidia in simulids: molecular and morphological characterization of microsporidia in the larvae of Simulium pertinax Kollar (Diptera: Simuliidae)

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...

Relationship between Mobility Limitations and the Places where Older Adults with Intellectual Disabilities Live

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

Treesearch

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

Treesearch

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...

Small mammal communities of streamside management zones in intensively managed pine forests of Arkansas

Treesearch

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...

Fermentation of model hemicelluloses by Prevotella strains and Butyrivibrio fibrisolvens in pure culture and in ruminal enrichment cultures

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...

Phylogeny, plant species, and plant diversity influence carbon use phenotypes among Fusarium populations in the rhizosphere microbiome

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…

Plant–microbial competition for nitrogen increases microbial activities and carbon loss in invaded soils

Treesearch

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…

Convergence of detrital stoichiometry predicts thresholds of nutrient-stimulated breakdown in streams

Treesearch

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

Treesearch

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

PubMed Central

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…

NUTRIENT METABOLISM AS A PHYTOTOXICITY INDICATOR OF THREE SAV SPECIES EXPOSED TO COPPER AND ATRAZINE UNDER SHORT-TERM CONDITIONS

EPA Science Inventory

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…

Influence of Cognitive Ability on Therapy Outcomes for Anomia in Adults with Chronic Poststroke Aphasia

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…

Above- and belowground competition from longleaf pine plantations limits performance of reintroduced herbaceous species

Treesearch

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...

Comparative transcriptome and secretome analysis of wood decay fungi Postia placenta and Phanerochaete chrysosporium

Treesearch

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...

Employment Programmes and Interventions Targeting Adults with Autism Spectrum Disorder: A Systematic Review of the Literature

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…

A flower in fruit's clothing: Pollination of jackfruit Artocarpus heterophyllus, Moraceae) by a new species of gall midge, Clinodiplosis ultracrepidata sp. nov. (Diptera: Cecidomyiidae)

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...

Leading the Ongoing Development of Collaborative Data Practices: Advancing a Schema for Diagnosis and Intervention

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…

Dopamine Receptor DOP-4 Modulates Habituation to Repetitive Photoactivation of a "C. elegans" Polymodal Nociceptor

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…

The physiological basis for regeneration response to variable retention harvest treatments in three pine species

Treesearch

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

Treesearch

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...

The Origin and Significance of the CCAM Line: Evidence from Chondrules and Dark Inclusions in Allende (CV3)

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.

Reporter Discrepancies among Parents, Adolescents, and Peers: Adolescent Attachment and Informant Depressive Symptoms as Explanatory Factors

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…

Demographic response of a shrubland bird to habitat creation, succession, and disturbance in a dynamic landscape

Treesearch

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

Treesearch

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

Treesearch

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...

TOLUENE EFFECTS ON OXIDATIVE STRESS IN BRAIN REGIONS OF YOUNG-ADULT, MIDDLE-AGE AND SENESCENT BROWN NORWAY RATS

EPA Science Inventory

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...

Multi-scale visualization and characterization of lignocellulosic plant cell wall deconstruction during thermochemical pretreatment

Treesearch

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...

Evasion of mucosal defenses during Aeromonas hydrophila infection of channel catfish (Ictalurus punctatus) skin

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...

Wounding induces changes in cytokinin and auxin content in potato tuber, but does not induce formation of gibberellins

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…