Clocking femtosecond X rays CAVALIERI, A. L; FRITZ, D. M; SIDDONS, D. P ...
Physical review letters,
03/2005, Letnik:
94, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Linear-accelerator-based sources will revolutionize ultrafast x-ray science due to their unprecedented brightness and short pulse duration. However, time-resolved studies at the resolution of the ...x-ray pulse duration are hampered by the inability to precisely synchronize an external laser to the accelerator. At the Sub-Picosecond Pulse Source at the Stanford Linear-Accelerator Center we solved this problem by measuring the arrival time of each high energy electron bunch with electro-optic sampling. This measurement indirectly determined the arrival time of each x-ray pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms.
To examine the responses to early IV administration of an anticoagulant or placebo started within 24 hours of stroke among persons with an ipsilateral occlusion or severe stenosis of the internal ...carotid artery (ICA) identified by carotid duplex imaging.
Patients with ischemic stroke of the cerebral hemisphere secondary to an ipsilateral occlusion or severe stenosis of the ICA generally have a poor prognosis. Early, accurate identification of these patients might permit improved treatment.
Exploratory analysis of outcomes at 7 days and 3 months was performed among patients enrolled in the Trial of Org 10172 in Acute Stroke Treatment (TOAST) who had an ischemic stroke in the cerebral hemisphere ipsilateral to an occlusion or a stenosis >50% of the ICA identified by carotid duplex imaging.
Regardless of treatment, patients with duplex evidence of an occlusion of the ICA had more severe strokes and poorer outcomes at 7 days and 3 months than patients who had a stenosis. Favorable outcomes at 7 days were noted in 64 of 119 patients given danaparoid (53.8%) and 41 of 108 patients treated with placebo (38.0%; p = 0.023). By 3 months, favorable outcomes were noted in 82 patients given danaparoid (68.3%) and 58 patients administered placebo (53.2%; p = 0.021).
Early identification by duplex imaging of an occlusion or severe stenosis of the ICA ipsilateral to a hemispheric ischemic stroke might improve selection of patients who could be treated with emergent anticoagulation. Further testing of this approach is needed.
Microvascular networks show promise for applications such as self-healing, self-cooling, and structural damage sensing. Fluid-filled micro-scale channels have been investigated extensively in the ...field of microfluidics, but three-dimensional networks in polymeric structural materials have been achieved only recently. The purpose of microvascular network integration is to provide a vehicle for the distribution and replenishment of active fluids throughout a matrix material enabling multifunctional operation. This perspective seeks to examine the advances in fabrication techniques, characterization, and new theoretical and computational tools for guiding design that are leading to systems with greater functionality and complexity.
Reduced fecundity, associated with severe mental disorders, places negative selection pressure on risk alleles and may explain, in part, why common variants have not been found that confer risk of ...disorders such as autism, schizophrenia and mental retardation. Thus, rare variants may account for a larger fraction of the overall genetic risk than previously assumed. In contrast to rare single nucleotide mutations, rare copy number variations (CNVs) can be detected using genome-wide single nucleotide polymorphism arrays. This has led to the identification of CNVs associated with mental retardation and autism. In a genome-wide search for CNVs associating with schizophrenia, we used a population-based sample to identify de novo CNVs by analysing 9,878 transmissions from parents to offspring. The 66 de novo CNVs identified were tested for association in a sample of 1,433 schizophrenia cases and 33,250 controls. Three deletions at 1q21.1, 15q11.2 and 15q13.3 showing nominal association with schizophrenia in the first sample (phase I) were followed up in a second sample of 3,285 cases and 7,951 controls (phase II). All three deletions significantly associate with schizophrenia and related psychoses in the combined sample. The identification of these rare, recurrent risk variants, having occurred independently in multiple founders and being subject to negative selection, is important in itself. CNV analysis may also point the way to the identification of additional and more prevalent risk variants in genes and pathways involved in schizophrenia.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Risky alcohol use is a major public health problem globally and in Sri Lanka. While a reduction in alcohol consumption can result in physical, mental, and social benefits, behaviour change is ...difficult to achieve. Effective, context-adapted interventions are required to minimise alcohol-related harm at a community level. THEATRE is a complex, community-based intervention evaluating whether a promising Sri Lankan pilot study that utilised arts-based research to moderate alcohol use can be scaled up. While the scaled-up pilot study protocol is presented elsewhere, the aim of this protocol paper is to describe the intervention programme theory and evaluation design, and modifications made to the study resulting from COVID-19 and the financial crisis. Drawing on the Behaviour Change Wheel (BCW) and Theoretical Domains Framework, behaviour change theories are presented with potential pathways to guide implementation and evaluation. Alcohol consumption patterns and context of drinking is detailed. The multifaceted intervention targets individuals and communities using arts-based interventions. Four of nine BCW functions are employed in the design of the intervention: education, persuasion, modelling and enablement, and training. Modifications made to the study due to COVID-19 and the financial crisis are described. Ethical approval was obtained from the Ethics Review Committee, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka (ERC/2018/21-July 2018 and Feb 2022) and the University of Sydney (2019/006). Findings will be disseminated locally to community members and key stakeholders and via international peer-reviewed publications.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This project compared the effects of grouping sows after weaning or within 2 d after insemination on sexual behavior, aggression, injuries, stress, and mating success. At weaning (d 0), 360 sows were ...housed in groups of 10 sows at 4.4 m2 per sow (group weaned GpW) or individual stalls (stall weaned StW), with 18 groups per treatment. Six days after weaning (d 6), 7 inseminated GpW sows were moved to pens at 2.1 m2 per sow and keeping acquainted sows, and simultaneously, groups of 7 inseminated StW sows were mixed at 2.1 m2 per sow. Group-weaned sows showed greater variation in the onset of estrus (P=0.02) but not in the length of estrus compared to StW sows (P=0.21), with 7% fewer GpW sows inseminated within 5 d of weaning (P=0.05). Group-weaned sows showed lower sexual receptivity scores, showing less spontaneous standing during boar exposure and partly compensating by a greater response to the back-pressure test (both P<0.01). The GpW treatment also showed greater variability in sows inseminated twice within 6 d of weaning, with 3 out of 18 pens having only 5 mated sows out of 10. Mixing after weaning resulted in higher levels of stress than mixing after insemination, with GpW sows having higher plasma cortisol concentration than StW sows on d 1 (P<0.001) but no treatment differences on d 7 in cortisol concentration or aggression at feeding (P=0.48). Group-weaned sows experienced greater weight loss during the first week postweaning (P=0.05). Anogenital sniffing in GpW sows was frequently observed from d 2 to 5, but mounting and flank nosing increased on d 4 and 5. Frequency of sexual behavior initiated by GpW sows tended to correlate with weight loss (P=0.08), and sexual behavior received correlated positively with cortisol concentration at d 1 (P=0.005). In conclusion, sows housed in groups at weaning and regrouped after insemination experienced higher stress than sows housed in individual stalls at weaning and mixed in groups after insemination. This resulted in lower mating success within 5 d of weaning, which in turn increased between-week variability. The lower sexual receptivity in sows grouped at weaning may be due to suppressed estrus-related behaviour, with ovulation occurring, or delayed ovulation beyond d 6. Further research is needed to identify underlying mechanisms to reduce variability, manage aggression and sexual behavior, and optimize estrus detection in group-housed weaning systems.
Recent studies suggest that the angiogenic cytokine vascular endothelial growth factor (VEGF) is involved in the pathogenesis of depression. However, only a few studies have investigated serum VEGF ...levels in individuals with depression, or the possible association between genetic variants within the VEGF gene and depression. The purpose of the present study was to investigate differences between serum VEGF levels in individuals with depression vs. control individuals, and associations between genetic markers located within VEGF and depression. In addition, determinants of the serum VEGF levels were identified. One-hundred and fifty-five depressed subjects and 280 controls were included in the study. All individuals returned a questionnaire and participated in a semi-structured diagnostic interview. Eleven single nucleotide polymorphisms were successfully analysed. VEGF levels were measured in serum by immunoassay and independent determinants of the serum VEGF level were assessed by generalized linear models.The main findings were that depression, severity of depression, previous depressive episodes, age and body mass index (BMI) were associated with higher serum VEGF levels. The genetic marker rs10434 was significantly associated with depression after correction for multiple testing, but not with the serum VEGF level. Our final model included depression and BMI as predictors of serum VEGF levels. Our study suggests a role for circulating serum VEGF in depression. Furthermore, our data also demonstrate that other factors than a diagnosis of depression influence the serum VEGF level. The importance of these factors should be emphasized when studies are compared.
To examine the joint associations of accelerometer-measured physical activity and sedentary time with all-cause mortality.
We conducted a harmonised meta-analysis including nine prospective cohort ...studies from four countries. 44 370 men and women were followed for 4.0 to 14.5 years during which 3451 participants died (7.8% mortality rate). Associations between different combinations of moderate-to-vigorous intensity physical activity (MVPA) and sedentary time were analysed at study level using Cox proportional hazards regression analysis and summarised using random effects meta-analysis.
Across cohorts, the average time spent sedentary ranged from 8.5 hours/day to 10.5 hours/day and 8 min/day to 35 min/day for MVPA. Compared with the referent group (highest physical activity/lowest sedentary time), the risk of death increased with lower levels of MVPA and greater amounts of sedentary time. Among those in the highest third of MVPA, the risk of death was not statistically different from the referent for those in the middle (16%; 95% CI 0.87% to 1.54%) and highest (40%; 95% CI 0.87% to 2.26%) thirds of sedentary time. Those in the lowest third of MVPA had a greater risk of death in all combinations with sedentary time; 65% (95% CI 1.25% to 2.19%), 65% (95% CI 1.24% to 2.21%) and 263% (95% CI 1.93% to 3.57%), respectively.
Higher sedentary time is associated with higher mortality in less active individuals when measured by accelerometry. About 30-40 min of MVPA per day attenuate the association between sedentary time and risk of death, which is lower than previous estimates from self-reported data.
Bipolar disorder is a heritable mental illness with complex etiology. We performed a genome-wide association study of 41,917 bipolar disorder cases and 371,549 controls of European ancestry, which ...identified 64 associated genomic loci. Bipolar disorder risk alleles were enriched in genes in synaptic signaling pathways and brain-expressed genes, particularly those with high specificity of expression in neurons of the prefrontal cortex and hippocampus. Significant signal enrichment was found in genes encoding targets of antipsychotics, calcium channel blockers, antiepileptics and anesthetics. Integrating expression quantitative trait locus data implicated 15 genes robustly linked to bipolar disorder via gene expression, encoding druggable targets such as HTR6, MCHR1, DCLK3 and FURIN. Analyses of bipolar disorder subtypes indicated high but imperfect genetic correlation between bipolar disorder type I and II and identified additional associated loci. Together, these results advance our understanding of the biological etiology of bipolar disorder, identify novel therapeutic leads and prioritize genes for functional follow-up studies.
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