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1.
A data acquisition system for time resolved X-ray scattering experiments using linear, quadrant or area gas proportional detectors with delay line readout based on commercially available hardware (National Instruments) is described. The system can easily be configured for recording data from point detectors (e.g. photomultipliers and photodiodes) and/or ancillary data only. Applications involving measurements with two different types of time to digital converters illustrate the features and performances of the system.  相似文献   
2.
This study looked at the quality and quantity of interactions between fathers and their firstborn 5-year-olds from the perspective of the family as a developmental interdependent system. The goals were to identify predictors of men's parenting from men's own adaptation (direct effects) and from their wives' characteristics (indirect effects), both measured during the expectancy. Twenty-three families from the Boston University Pregnancy and Parenthood Project made up the sample. Measures included self-report scales, observations, and semistructured interviews. Several of men's psychological characteristics, particularly their autonomy and job satisfaction, predicted their play time and the quality of their interactions with their children. Women's autonomy, occupation, and age in the expectancy predicted men's caretaking and weekday time involvement with their 5-year-olds. We suggest that the findings can best be explained by the concepts of complementarity and identification. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
OBJECTIVE: This investigation assessed whether current post-traumatic stress disorder (PTSD) was associated with impaired functioning in a nationally representative sample of female Vietnam veterans. METHODS: Logistic models were used to determine the association between PTSD and outcome while adjusting for demographic characteristics and medical and psychiatric co-morbidities. RESULTS: PTSD was associated with significantly elevated odds of poorer functioning in five of the six outcome domains; only the association between perpetration of violence in the past year and PTSD did not achieve statistical significance. After adjusting for demographics and medical and psychiatric co-morbidities, PTSD remained associated with significantly elevated odds of bed days, poorer physical health, and currently not working. CONCLUSIONS: Among female Vietnam veterans PTSD is associated with a broad profile of functional impairment. The significantly increased odds of impaired functioning and diminished quality of life suggest that PTSD may be the core problem of the set of problems afflicting female Vietnam veterans.  相似文献   
4.
Expression levels of fast-twitch (SERCA1), slow-twitch (SERCA2a) and "housekeeping" (SERCA2b) isoforms of the sarcoplasmic reticulum Ca(2+)-transport ATPase were monitored during regeneration of rat soleus muscles following necrosis induced by the toxin notexin at the tissue level by Western blot analysis and at the cellular level by immunocytochemical analysis. Due to necrosis, levels of muscle-specific SERCA1 and SERCA2a isoforms dropped to low levels on the third day after injection of the toxin. Subsequently, during regeneration both isoforms recovered but with a different time course. Expression of the fast type SERCA1 increased first. This type showed its most pronounced increase between day 3 and 10. Expression of the slow type SERCA2a was biphasic. After an increase to approximately one third of the control value on days 5-10, it showed its main increase up to the control level between day 10 and 21. Expression levels of the house-keeping SERCA2b isoform remained relatively constant throughout the 4 weeks of regeneration. Between day 10 and 28, when new innervation is established, SERCA2a expression spread gradually over almost all fibers whereas the number of SERCA1-expressing fibers decreased and only a limited number of fibers co-expressed SERCA1 and SERCA2a. At 4 weeks of regeneration, expression of the fast isoform was found only in 12% of the fibers, whereas the slow form was found in 98% of the fibers. In the contralateral untreated soleus muscles, 26% SERCA1-positive and 81% SERCA2a-positive fibers were observed. Immunocytochemical analysis showed that SERCA1 and SERCA2a were co-expressed with fast and slow myosin isoforms in fibers of normal muscles but in regenerated muscle only slow myosin and slow SERCA isoforms correlated. The results show that during regeneration levels of fast and slow SERCA proteins change in a similar way as their mRNAs do. However, in regenerated soleus, unlike in normal muscle, expression of slow SERCA is coregulated only with the slow myosin isoform. This finding is in agreement with the fact that the number of slow type fibers is increased in regenerated soleus.  相似文献   
5.
The aim of this study was to evaluate the combined effect of salt (sodium chloride, 0–8% w/v), sorbate (potassium sorbate, 0–4.5% w/v), nisin (0–500 ppm) and lysozyme (0–500 ppm) on the survival of Clostridium sporogenes as a non‐toxigenic surrogate of Clostridium botulinum in terms of the probability of growth by using a central composite rotatable design. The results indicated that salt and sorbate were the most effective factors in preventing the growth of Cl. sporogenes in high‐moisture (>95%) and low‐acid conditions. The probability of growth of Cl. sporogenes in broth was reduced by combinations of salt and sorbate. Nisin and lysozyme had insignificant effects on the probability of growth of Cl. sporogenes (P > 0.05). Lysozyme individually and in combination with nisin had no inhibitory effect on Cl. sporogenes. Overall, the addition of sorbate and lysozyme may allow the salt concentration to be reduced while preventing growth.  相似文献   
6.
In the United Kingdom, blanket antibiotic dry cow therapy (BDCT) is commonly prescribed. An alternate strategy is selective dry cow therapy (SDCT) whereby a teat sealant is given instead of an antibiotic to cows with a low probability of infection. Switching from BDCT to SDCT can significantly reduce antibiotic use. The aims of this study were to explore how veterinarians (vets) rationalized their prescribing decisions for mammary treatments at drying off, and the barriers and motivators they perceived to implementing SDCT. Face-to-face interviews were conducted with 20 purposively recruited vets from 6 practices in England, United Kingdom. The data were analyzed qualitatively using an inductive thematic analysis. The majority of participants stated a personal preference for SDCT because it constitutes more responsible antibiotic use. On the majority of farms, the prescribing decision was taken by a senior veterinarian and BDCT was prescribed. Less experienced vets expressed a desire to be more involved in the decision-making process. The first theme, prioritizing responsible antimicrobial prescribing, encapsulated the difficulties vets expressed engaging with farmers, conflicts of interest, and vets’ determination to take action. The second theme, the effect of a vet's experience on their ability to influence farmers, focused on the specific challenges faced by less experienced vets and the importance of vets being both trusted by farmers and being knowledgeable. The third theme, vets’ perceptions about the risk and complexity of implementing SDCT, revealed markedly different levels of concern and fears about adverse outcomes with teat sealants versus antibiotics. The results also showed differences in perceptions about how difficult SDCT is to implement in practice. The last theme, vets’ suggestions for facilitating the introduction of SDCT, was wide ranging and provided useful insight from a veterinary perspective into ways to facilitate SDCT. Initiatives that seek to alter vets’ perceptions of the risks associated with switching to using SDCT are likely to prove useful in facilitating change. Our results also suggest that it is vital for senior vets to take a leading role in facilitating farms to implement SDCT. Less experienced colleagues may benefit from more help from senior vets to gain the trust of farmers and to become involved more quickly in herd-level preventive medicine. Vets must work together and take a united approach to reduce antimicrobial use.  相似文献   
7.
The aim of this study was to investigate the effect of freeze‐drying, hot air‐drying and vacuum‐drying at 70, 90 and 110 °C, on dried lemon pomace polyphenols and antioxidant capacity. The total phenolic content and antioxidant capacity were higher in lemon pomace dried by hot air or under vacuum than those dried by freeze‐drying and increased as the temperature increased. The highest total flavonoid content was recorded in the pomace dried under vacuum at 70 and 90 °C. Lemon pomace dried by freeze‐drying had the highest neohesperidin content, whereas pomace dried under vacuum at 70 °C had the highest rutin and p‐coumaric acid content. The highest gallic acid content was recorded in the pomace dried by hot air at 110 °C. The results of this study indicate that drying technique should be carefully selected according to the bioactive compounds aimed to be extracted.  相似文献   
8.
Reverse current in diodes can be dominated by generation processes, depending exponentially on temperature according to the rate-limiting step in the generation process. In this report, the current-voltage-temperature (IVT) relationship is analyzed for several midwave infrared and long-wave infrared (MWIR x = 0.295, LWIR x = 0.233) Hg1−x Cd x Te (MCT) diodes. The energy varied from diode to diode. At high reverse biases, the energy tends toward the band gap energy. Close to zero bias, the energy ranged from 0.06 to 0.1 eV. Deep level transient spectroscopy (DLTS) showed a broad peak centered at 55–80 K for the MWIR MCT. Comparison of the DLTS spectrum to a simulation based on the energy and capture cross section from a rate window analysis shows that the peak is a band of traps. The capacitance transient amplitude increased as the filling pulse increased from 1 μs to 0.1 s, consistent with capture at a dislocation. A shift to lower temperatures for the peak was also observed when the diodes are cooled under forward bias. The shift is reversible, indicating that the traps consist at least partially of a bistable defect.  相似文献   
9.
10.
BACKGROUND: The evidence-based approach to medical care involves the explicit use of evidence on the magnitude of the effects of interventions to inform diagnostic and treatment decisions. This article critiques current mainstream guidelines on the management of hypertension in the elderly (aged 60 years and over) and presents an alternative evidence-based approach. METHODS: Three major national and international guidelines for the management of hypertension from the United Kingdom (UK), the United States (US) and from a joint World Health Organisation/International Society of Hypertension (WHO/ISH) Working Party were appraised and the evidence on which they were based was reviewed. The relevant evidence was also assessed to determine the likely magnitude of risks and benefits of anti-hypertensive treatment in older people and an alternative approach to making treatment decisions, based on the New Zealand guidelines for the management of hypertension, is described. RESULTS: Hypertension management guidelines from the UK, US and WHO/ISH made similar recommendations about which elderly patients should be treated, although there were some ambiguities in their advice. Treatment recommendations were based primarily on blood pressure levels which were set at about 160 mm Hg systolic and/or 90 mm Hg diastolic. The threshold levels were based mainly on the cut-off blood pressure levels used in randomised trials of anti-hypertensive drug treatment, rather than the estimated magnitude of treatment benefit. Each of the guidelines acknowledged the important effect of associated cardiovascular disease (CVD) risk factors on the likely benefits of treatment, but did not expand on the magnitude of this effect. No patient-specific estimates of the likely absolute benefits of treatment were provided in any of the guidelines. In contrast the New Zealand guidelines for the management of hypertension recommend the use of explicit estimates of absolute CVD risks and benefits to inform treatment decisions. They were designed to provide practitioners with estimates of the likely absolute risk of CVD in patients with different risk factor profiles and with estimates of the absolute benefits of treatment. The New Zealand guidelines recommend that drug treatment be considered in patients with a 5-year risk of CVD of about 10-15% or more; approximately 25 patients with a 10-15% risk would require treatment for 5 years to prevent one CVD event. As elderly patients are generally at higher absolute CVD risk than younger people, the New Zealand recommendation give priority to the treatment of older patients. In order to take account of differences in life expectancy and the medical costs of caring for elderly people, absolute risk-based guidelines can be improved by incorporating potential years of life gained from treatment and the cost-effectiveness of treatment expressed as $/quality adjusted life years gained. Preliminary analyses indicate that the cost-effectiveness of treatment is generally greatest in patients in their 60s and early 70s. Treatment in younger people is not usually very cost-effective because of their low absolute risk of CVD and the cost-effectiveness of treatment in people over about 75 years declines because of the increasing cost of non-CVD morbidity. CONCLUSIONS: The explicit assessment of absolute CVD risks and likely treatment benefits in patients with hypertension can usefully inform treatment decisions and provide a more rational basis for initiating therapy than blood pressure levels alone. This approach highlights the generally greater CVD risk and potential treatment benefits in older compared with younger hypertensive patients. The absolute risk-based approach can be further enhanced by providing decision makers with patient-specific data on the potential life years gained from treatment and its cost-effectiveness. (ABSTRACT TRUNCATED)  相似文献   
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