2,046 research outputs found
Experimental Study of Vertical Flight Path Mode Awareness
An experimental simulator study was run to test pilot detection of an error in autopilot mode selection. Active airline air crew were asked to fly landing approaches by commanding the Flight Path Angle mode while monitoring the approach with both a Head Up Display and Head Down Displays. During one approach, the Vertical Speed mode was intentionally triggered by an experimenter instead, causing a high rate of descent below the intended glide path. Of the 12 pilots, 10 were unable to detect the high descent rate prior to significant glide path deviation
Determining the Role of Choline Dehydrogenase in Sperm Cell Function
Approximately 15% of couples suffer from infertility and male factor infertility is the suspected cause in about half of these couples. 40-60% these male factor infertility cases are idiopathic, but genetic aberrations are associated with infertility in as many as 30% of these. Although the relationship between nutrition and reproduction is established, the role of micronutrient metabolism in male fertility is understudied. Choline, an essential nutrient for humans, is important for maintaining a healthy pregnancy and normal fetal development. Choline is necessary for normal mating behavior and male fertility in D. melanogaster but the reason why remains unknown. Choline dehydrogenase (CHDH) catalyzes the conversion of choline into betaine, a methyl group donor and osmolyte. Several single nucleotide polymorphisms (SNPs)within the CHDH gene may alter the function of the CHDH. A choline dehydrogenase knockout mouse (Chdh-/-) was created to model loss-of-function mutations in humans. Mutation of Chdh reduced CHDH activity and decreased betaine concentration in all tissues that normally express this enzyme. Fetal viability, growth and one-year survival rates were not affected. Chdh-/- animals had 59% more plasma homocysteine, but hepatic AdoMet and AdoHcy were unchanged. Chdh-/- males were infertile due to poor sperm motility. Abnormal mitochondrial morphology and function were observed in Chdh-/- sperm. ATP concentration was 55% lower in Chdh-/- sperm. Dietary betaine supplementation resulted in increased Chdh-/- sperm motility, and full restoration of ATP concentration. CHDH SNP rs12676 (G233T; R→L) and IL17βR SNP rs1025689 (G126C; P→P) are associated with changes in mitochondrial function and sperm motility in men. Men who were TT for rs12676 produced sperm with dysmorphic mitochondria. Compared to GG subjects, sperm produced by GT subjects contained 40% less ATP; men who were TT for this SNP had 73% less ATP. Motility characteristics were changed in men with at least one minor allele of either rs12676 or rs1025689. CHDH protein was decreased in primary hepatocytes from individuals who were TT for rs12676, indicating this SNP marks a functional haplotype. We propose that aberrant choline metabolism stemming from decreased CHDH activity may be an underlying cause of idiopathic male factor infertility in men
Development of a translational model to screen medications for cocaine use disorder I: Choice between cocaine and food in rhesus monkeys
Background Homologous cocaine self-administration procedures in laboratory animals and humans may facilitate translational research for medications development to treat cocaine dependence. This study, therefore, sought to establish choice between cocaine and an alternative reinforcer in rhesus monkeys responding under a procedure back-translated from previous human studies and homologous to a human laboratory procedure described in a companion paper. Methods Four rhesus monkeys with chronic indwelling intravenous catheters had access to cocaine injections (0, 0.043, 0.14, or 0.43 mg/kg/injection) and food (0, 1, 3, or 10 1 g banana-flavored food pellets). During daily 5 h sessions, a single cocaine dose and a single food-reinforcer magnitude were available in 10 30-min trials. During the initial “sample” trial, the available cocaine and food reinforcer were delivered non-contingently. During each of the subsequent nine “choice” trials, responding could produce either the cocaine or food reinforcer under an independent concurrent progressive-ratio schedule. Results Preference was governed by the cocaine dose and food-reinforcer magnitude, and increasing cocaine doses produced dose-dependent increases in cocaine choice at all food-reinforcer magnitudes. Effects of the candidate medication lisdexamfetamine(0.32–3.2 mg/kg/day) were then examined on choice between 0.14 mg/kg/injection cocaine and 10 pellets. Under baseline conditions, this reinforcer pair maintained an average of approximately 6 cocaine and 3 food choices. Lisdexamfetamine dose-dependently decreased cocaine choice in all monkeys, but food choice was not significantly altered. Conclusions These results support utility of this procedure in rhesus monkeys as one component of a platform for translational research on medications development to treat cocaine use disorder
Stranger in the Room: Illuminating Female Identity Through Irish Drama
Indiana University-Purdue University Indianapolis (IUPUI)This thesis centers on a country that has produced some of the greatest and most important English language dramas of the past two centuries. Within this cultural context, this thesis is also about a feminine revival in Irish theatre and how this can be a powerful tool to incite change. Early in history, Irish writers, and specifically dramatists, recreated a type of theatre that captured the true essence of what it meant to be Irish by representing their struggles, frustrations and humor. The Irish talent for storytelling connects back to its Gaelic roots and has remained a constant in the life of a culture that has passed down this art form for centuries. The focus of this thesis is to examine three contemporary Irish plays by prominent playwrights who came to the world of theatre from very different backgrounds. Each play is written by a different hand, yet all share a vital common denominator: the interaction of female character groups – groups that are central to the action of each play. What incited my interest in these three plays – Brian Friel’s Dancing at Lughnasa, Anne Devlin’s Ourselves Alone and Marina Carr’s The Mai – was the playwright’s ability to expose what had been silenced in Irish history for so long. Each female character portrays one important aspect of Irish womanhood that has been tragically understated in the nation’s literature since the death of John Millington Synge: woman’s struggle between what she wants to be and who she is expected to be. These three plays will be scrutinized in terms of three elements of social control contributing to woman’s struggle in Irish society: myth, church and patriarchal tradition
The role of religiousness on substance-use disorder treatment outcomes: a comparison of black and white adolescents
This study compares 41 Black and 124 White adolescents at intake and discharge from a residential treatment program for substance-use disorders. Study data were obtained as part of a larger study (N = 195) that sought to assess the relationship of helping behavior and addiction recovery. This post-hoc analysis aims to identify cultural strengths that may be associated with recovery from substance-use disorders among Black adolescents. Using regression analyses and controlling for the severity of substance use and background variables that distinguish racial groups, religious practices and behaviors at intake were examined. Specifically, Black youth and White youth were compared on treatment outcomes, including alcohol or drug use during treatment, drug craving, 12-Step work, and 12-Step helping. The burden of health and socioeconomic disparities at intake did not disproportionately disfavor Black adolescents. Outcomes related to 12-Step measures were similar between Black and White youth. White adolescents reported higher craving scores at discharge, and Black adolescents were more likely to use drugs during treatment. High levels of religiousness at treatment intake were linked to greater 12-Step work and greater 12-Step helping at discharge. High levels of religiousness at intake were not related to drug use during treatment or to craving scores at discharge. The relationship between intake levels of religiousness and treatment-related outcomes did not differ by race.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3437261/Accepted manuscrip
Spatially Resolved Images of Dust Belt(s) Around the Planet-hosting Subgiant Kappa CrB
We present Herschel spatially resolved images of the debris disc orbiting the
subgiant Kappa CrB. Not only are these the first resolved images of a debris
disc orbiting a subgiant, but Kappa CrB is a rare example of an intermediate
mass star where a detailed study of the structure of the planetary system can
be made, including both planets and planetesimal belt(s). The only way to
discover planets around such stars using the radial velocity technique is to
observe 'retired' A stars, which are cooler and slower rotators compared to
their main-sequence counterparts. A planetary companion has already been
detected orbiting the subgiant Kappa CrB, with revised parameters of m sin i =
2.1MJ and apl = 2.8AU (Johnson et al. 2008a). We present additional Keck I
HIRES radial velocity measurements that provide evidence for a second planetary
companion, alongside Keck II AO imaging that places an upper limit on the mass
of this companion. Modelling of our Herschel images shows that the dust is
broadly distributed, but cannot distinguish between a single wide belt (from 20
to 220AU) or two narrow dust belts (at around 40 and 165AU). Given the
existence of a second planetary companion beyond approximately 3AU it is
possible that the absence of dust within approximately 20AU is caused by
dynamical depletion, although the observations are not inconsistent with
depletion of these regions by collisional erosion, which occurs at higher rates
closer to the star.Comment: Updated abstrac
Building a Participatory Culture: Collaborating with Student Organizations for Twenty-first Century Library Instruction
Today’s students are critical thinkers, collaborators, and creators. They expect to participate in twenty-first century learning environments not as passive information consumers (think lectures), but as active contributors (think team-based problem-solving). There are opportunities for instruction librarians to collaborate directly with student-led organizations. These partnerships have the potential to increase attendance at library events and provide platforms for students to engage in richer forms of exploratory learning that incorporate twenty-first century skills. This article will discuss the literature surrounding library instruction collaborations, identify “Librarian–Student Organization Collaborations” as an important form of partnership, and supply specific case studies of successful library instruction events based on these collaborations
Nutrition and Metabolic Correlates of Obesity and Inflammation: Clinical Considerations
Since 1980, the global prevalence of obesity has doubled; in the United States, it has almost tripled. Billions of people are overweight and obese; the WHO reports that >65% of the world’s population die of diseases related to overweight rather than underweight. Obesity is a complex disease that can be studied from “metropolis to metabolite”—that is, beginning at the policy and the population level through epidemiology and intervention studies; to bench work including preclinical models, tissue, and cell culture studies; to biochemical assays; and to metabolomics. Metabolomics is the next research frontier because it provides a real-time snapshot of biochemical building blocks and products of cellular processes. This report comments on practical considerations when conducting metabolomics research. The pros and cons and important study design concerns are addressed to aid in increasing metabolomics research in the United States. The link between metabolism and inflammation is an understudied phenomenon that has great potential to transform our understanding of immunometabolism in obesity, diabetes, cancer, and other diseases; metabolomics promises to be an important tool in understanding the complex relations between factors contributing to such diseases
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