1,699 research outputs found
Four-nucleon contact interactions from holographic QCD
We calculate the low energy constants of four-nucleon interactions in an
effective chiral Lagrangian in holographic QCD. We start with a D4-D8 model to
obtain meson-nucleon interactions and then integrate out massive mesons to
obtain the four-nucleon interactions in 4D. We end up with two low energy
constants at the leading order and seven of them at the next leading order,
which is consistent with the effective chiral Lagrangian. The values of the low
energy constants are evaluated with the first five Kaluza-Klein resonances.Comment: 28 page
Study of Sexual Functioning Determinants in Breast Cancer Survivors
Our goal was to identify the treatment, personal, interpersonal, and hormonal (testosterone) factors in breast cancer survivors (BCSs) that determine sexual dysfunction. The treatment variables studied were type of surgery, chemotherapy, radiation, and tamoxifen. The personal, interpersonal, and physiologic factors were depression, body image, age, relationship distress, and testosterone levels. A sample of 55 female breast cancer survivors seen for routine follow-up appointments from July 2002 to September 2002 were recruited to complete the Female Sexual Functioning Index (FSFI), Hamilton Depression Inventory (HDI), Body Image Survey (BIS), Marital Satisfaction Inventory-Revised (MSI-R), a demographic questionnaire, and have a serum testosterone level drawn. The average time since diagnosis was 4.4 years (SD 3.4 years). No associations were found between the type of cancer treatment, hormonal levels, and sexual functioning. BCS sexual functioning was significantly poorer than published normal controls in all areas but desire. The BCSs’ level of relationship distress was the most significant variable affecting arousal, orgasm, lubrication, satisfaction, and sexual pain. Depression and having traditional role preferences were the most important determinants of lower sexual desire. BCSs on antidepressants had higher levels of arousal and orgasm dysfunction. Women who were older had significantly more concerns about vaginal lubrication and pain. Relationship concerns, depression, and age are important influences in the development of BCS sexual dysfunction. The relationship of testosterone and sexual dysfunction needs further study with larger samples and more accurate assay techniques.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72034/1/j.1075-122X.2005.00131.x.pd
Adherence to self-administered tuberculosis treatment in a high HIV-prevalence setting: a cross-sectional survey in Homa Bay, Kenya.
Good adherence to treatment is crucial to control tuberculosis (TB). Efficiency and feasibility of directly observed therapy (DOT) under routine program conditions have been questioned. As an alternative, Médecins sans Frontières introduced self-administered therapy (SAT) in several TB programs. We aimed to measure adherence to TB treatment among patients receiving TB chemotherapy with fixed dose combination (FDC) under SAT at the Homa Bay district hospital (Kenya). A second objective was to compare the adherence agreement between different assessment tools
Pregnant women with bronchial asthma benefit from progressive muscle relaxation: A randomized, prospective, controlled trial
Background: Asthma is a serious medical problem in pregnancy and is often associated with stress, anger and poor quality of life. The aim of this study was to determine the efficacy of progressive muscle relaxation (PMR) on change in blood pressure, lung parameters, heart rate, anger and health-related quality of life in pregnant women with bronchial asthma. Methods: We treated a sample of 64 pregnant women with bronchial asthma from the local population in an 8-week randomized, prospective, controlled trial. Thirty-two were selected for PMR, and 32 received a placebo intervention. The systolic blood pressure, forced expiratory volume in the first second, peak expiratory flow and heart rate were tested, and the State-Trait Anger Expression Inventory and Health Survey (SF-36) were employed. Results: According to the intend-to-treat principle, a significant reduction in systolic blood pressure and a significant increase in both forced expiratory volume in the first second and peak expiratory flow were observed after PMR. The heart rate showed a significant increase in the coefficient of variation, root mean square of successive differences and high frequency ranges, in addition to a significant reduction in low and middle frequency ranges. A significant reduction on three of five State-Trait Anger Expression Inventory scales, and a significant increase on seven of eight SF-36 scales were observed. Conclusions: PMR appears to be an effective method to improve blood pressure, lung parameters and heart rate, and to decrease anger levels, thus enhancing health-related quality of life in pregnant women with bronchial asthma. Copyright (c) 2006 S. Karger AG, Basel
Developing and implementing an integrated delirium prevention system of care:a theory driven, participatory research study
Background: Delirium is a common complication for older people in hospital. Evidence suggests that delirium incidence in hospital may be reduced by about a third through a multi-component intervention targeted at known modifiable risk factors. We describe the research design and conceptual framework underpinning it that informed the development of a novel delirium prevention system of care for acute hospital wards. Particular focus of the study was on developing an implementation process aimed at embedding practice change within routine care delivery. Methods: We adopted a participatory action research approach involving staff, volunteers, and patient and carer representatives in three northern NHS Trusts in England. We employed Normalization Process Theory to explore knowledge and ward practices on delirium and delirium prevention. We established a Development Team in each Trust comprising senior and frontline staff from selected wards, and others with a potential role or interest in delirium prevention. Data collection included facilitated workshops, relevant documents/records, qualitative one-to-one interviews and focus groups with multiple stakeholders and observation of ward practices. We used grounded theory strategies in analysing and synthesising data. Results: Awareness of delirium was variable among staff with no attention on delirium prevention at any level; delirium prevention was typically neither understood nor perceived as meaningful. The busy, chaotic and challenging ward life rhythm focused primarily on diagnostics, clinical observations and treatment. Ward practices pertinent to delirium prevention were undertaken inconsistently. Staff welcomed the possibility of volunteers being engaged in delirium prevention work, but existing systems for volunteer support were viewed as a barrier. Our evolving conception of an integrated model of delirium prevention presented major implementation challenges flowing from minimal understanding of delirium prevention and securing engagement of volunteers alongside practice change. The resulting Prevention of Delirium (POD) Programme combines a multi-component delirium prevention and implementation process, incorporating systems and mechanisms to introduce and embed delirium prevention into routine ward practices. Conclusions: Although our substantive interest was in delirium prevention, the conceptual and methodological strategies pursued have implications for implementing and sustaining practice and service improvements more broadly
The transcriptional response of Caenorhabditis elegans to ivermectin exposure identifies novel genes involved in the response to reduced food intake
We have examined the transcriptional response of Caenorhabditis elegans following exposure to the anthelmintic drug ivermectin (IVM) using whole genome microarrays and real-time QPCR. Our original aim was to identify candidate molecules involved in IVM metabolism and/or excretion. For this reason the IVM tolerant strain, DA1316, was used to minimise transcriptomic changes related to the phenotype of drug exposure. However, unlike equivalent work with benzimidazole drugs, very few of the induced genes were members of xenobiotic metabolising enzyme families. Instead, the transcriptional response was dominated by genes associated with fat mobilization and fatty acid metabolism including catalase, esterase, and fatty acid CoA synthetase genes. This is consistent with the reduction in pharyngeal pumping, and consequential reduction in food intake, upon exposure of DA1316 worms to IVM. Genes with the highest fold change in response to IVM exposure, cyp-37B1, mtl-1 and scl-2, were comparably up-regulated in response to short–term food withdrawal (4 hr) independent of IVM exposure, and GFP reporter constructs confirm their expression in tissues associated with fat storage (intestine and hypodermis). These experiments have serendipitously identified novel genes involved in an early response of C. elegans to reduced food intake and may provide insight into similar processes in higher organisms
Scaling laws near the conformal window of many-flavor QCD
We derive universal scaling laws for physical observables such as the
critical temperature, the chiral condensate, and the pion decay constant as a
function of the flavor number near the conformal window of many-flavor QCD in
the chiral limit. We argue on general grounds that the associated critical
exponents are all interrelated and can be determined from the critical exponent
of the running gauge coupling at the Caswell-Banks-Zaks infrared fixed point.
We illustrate our findings with the aid of nonperturbative functional
Renormalization Group (RG) calculations and low-energy QCD models.Comment: 18 pages, 4 figures, references added and discussion expanded
(matches JHEP version
The RAD51 and DMC1 homoeologous genes of bread wheat: cloning, molecular characterization and expression analysis
<p>Abstract</p> <p>Background</p> <p>Meiotic recombination in eukaryotes requires two homologues of the <it>E. coli </it>RecA proteins: Rad51 and Dmc1. Both proteins play important roles in the binding of single stranded DNA, homology search, strand invasion and strand exchange. Meiotic recombination has been well studied in Arabidopsis, rice, maize and the orthologues of <it>RAD51 </it>and <it>DMC1 </it>have been characterized. However genetic analysis of the <it>RAD51 </it>and <it>DMC1 </it>genes in bread wheat has been hampered due to the absence of complete sequence information and because of the existence of multiple copies of each gene in the hexaploid wheat genome.</p> <p>Findings</p> <p>In this study we have identified that <it>TaRAD51 </it>and <it>TaDMC1 </it>homoeologues are located on group 7 and group 5 chromosomes of hexaploid wheat, respectively. Comparative sequence analysis of cDNA derived from the <it>TaRAD51 </it>and <it>TaDMC1 </it>homoeologues revealed limited sequence divergence at both the nucleotide and the amino acid level. Indeed, comparisons between the predicted amino acid sequences of <it>TaRAD51 </it>and <it>TaDMC1 </it>and those of other eukaryotes reveal a high degree of evolutionary conservation. Despite the high degree of sequence conservation at the nucleotide level, genome-specific primers for cDNAs of <it>TaRAD51 </it>and <it>TaDMC1 </it>were developed to evaluate expression patterns of individual homoeologues during meiosis. QRT-PCR analysis showed that expression of the <it>TaRAD51 </it>and <it>TaDMC1 </it>cDNA homoeologues was largely restricted to meiotic tissue, with elevated levels observed during the stages of prophase I when meiotic recombination occurs. All three homoeologues of both strand-exchange proteins (<it>TaRAD51 </it>and <it>TaDMC1</it>) are expressed in wheat.</p> <p>Conclusions</p> <p>Bread wheat contains three expressed copies of each of the <it>TaRAD51 </it>and <it>TaDMC1 </it>homoeologues. While differences were detected between the three cDNA homoeologues of <it>TaRAD51 </it>as well as the three homoeologues of <it>TaDMC1</it>, it is unlikely that the predicted amino acid substitutions would have an effect on the protein structure, based on our three-dimensional structure prediction analyses. There are differences in the levels of expression of the three homoeologues of <it>TaRAD51 </it>and <it>TaDMC1 </it>as determined by QRT-PCR and if these differences are reflected at the protein level, bread wheat may be more dependent upon a particular homoeologue to achieve full fertility than all three equally.</p
Segregation of object and background motion in the retina
An important task in vision is to detect objects moving within a stationary scene. During normal viewing this is complicated by the presence of eye movements that continually scan the image across the retina, even during fixation. To detect moving objects, the brain must distinguish local motion within the scene from the global retinal image drift due to fixational eye movements. We have found that this process begins in the retina: a subset of retinal ganglion cells responds to motion in the receptive field centre, but only if the wider surround moves with a different trajectory. This selectivity for differential motion is independent of direction, and can be explained by a model of retinal circuitry that invokes pooling over nonlinear interneurons. The suppression by global image motion is probably mediated by polyaxonal, wide-field amacrine cells with transient responses. We show how a population of ganglion cells selective for differential motion can rapidly flag moving objects, and even segregate multiple moving objects
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