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71.
Research suggests that presurgical personality attributes influence postsurgical well-being in both patients and their spouses in the context of coronary artery bypass grafting (CABG) surgery. The authors hypothesized that a spouse's characteristics would influence a partner's psychological well-being, regardless of whether he or she was the patient or the caregiver. In this study, 111 male patients and their caregiver spouses completed measures of neuroticism, optimism, perceived marital satisfaction, and depression prior to elective CABG. Follow-up was conducted at 18 months. As expected, higher caregiver presurgical neuroticism predicted higher patient depressive symptoms at follow-up, with caregiver's concurrent 18-month affect controlled for. Likewise, higher patient presurgical neuroticism predicted higher caregiver depressive symptoms at follow-up. Additionally, higher patient presurgical depressive symptoms and lower presurgical optimism contributed to greater caregiving burden. Relationship satisfaction moderated these effects. These results suggest that partners' personality traits are important determinants of both patients' and their caregiving spouses' well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
Beacon-Less Geographic Routing in Real Wireless Sensor Networks   总被引:2,自引:1,他引:1       下载免费PDF全文
Geographic Routing(GR)algorithms require nodes to periodically transmit HELLO messages to allow neigh- bors to know their positions(beaconing mechanism).Beacon-less routing algorithms have recently been proposed to reduce the control overheads due to these messages.However,existing beacon-less algorithms have not considered realistic physical layers.Therefore,those algorithms cannot work properly in realistic scenarios.In this paper we present a new beacon- less routing protocol called BOSS.Its design is based on the conclusions of our open-field experiments using Tmote-sky sensors.BOSS is adapted to error-prone networks and incorporates a new mechanism to reduce collisions and duplicate messages produced during the selection of the next forwarder node.We compare BOSS with Beacon-Less Routing(BLR) and Contention-Based Forwarding(CBF)algorithms through extensive simulations.The results show that our scheme is able to achieve almost perfect packet delivery ratio(like BLR)while having a low bandwidth consumption(even lower than CBF).Additionally,we carried out an empirical evaluation in a real testbed that shows the correctness of our simulation results.  相似文献   
73.
Inflammatory bowel disease is a chronic disorder including ulcerative colitis and Crohn’s disease (CD). Gut dysbiosis is often associated with CD, and metagenomics allows a better understanding of the microbial communities involved. The objective of this study was to reconstruct in silico carbohydrate metabolic capabilities from metagenome-assembled genomes (MAGs) obtained from healthy and CD individuals. This computational method was developed as a mean to aid rationally designed prebiotic interventions to rebalance CD dysbiosis, with a focus on metabolism of emergent prebiotics derived from arabinoxylan and pectin. Up to 1196 and 1577 MAGs were recovered from CD and healthy people, respectively. MAGs of Akkermansia muciniphila, Barnesiella viscericola DSM 18177 and Paraprevotella xylaniphila YIT 11841 showed a wide range of unique and specific enzymes acting on arabinoxylan and pectin. These glycosidases were also found in MAGs recovered from CD patients. Interestingly, these arabinoxylan and pectin degraders are predicted to exhibit metabolic interactions with other gut microbes reduced in CD. Thus, administration of arabinoxylan and pectin may ameliorate dysbiosis in CD by promoting species with key metabolic functions, capable of cross-feeding other beneficial species. These computational methods may be of special interest for the rational design of prebiotic ingredients targeting at CD.  相似文献   
74.
Background: Clinical diagnosis of Alzheimer’s disease (AD) increasingly incorporates CSF biomarkers. However, due to the intrinsic variability of the immunodetection techniques used to measure these biomarkers, establishing in-house cutoffs defining the positivity/negativity of CSF biomarkers is recommended. However, the cutoffs currently published are usually reported by using cross-sectional datasets, not providing evidence about its intrinsic prognostic value when applied to real-world memory clinic cases. Methods: We quantified CSF Aβ1-42, Aβ1-40, t-Tau, and p181Tau with standard INNOTEST® ELISA and Lumipulse G® chemiluminescence enzyme immunoassay (CLEIA) performed on the automated Lumipulse G600II. Determination of cutoffs included patients clinically diagnosed with probable Alzheimer’s disease (AD, n = 37) and subjective cognitive decline subjects (SCD, n = 45), cognitively stable for 3 years and with no evidence of brain amyloidosis in 18F-Florbetaben-labeled positron emission tomography (FBB-PET). To compare both methods, a subset of samples for Aβ1-42 (n = 519), t-Tau (n = 399), p181Tau (n = 77), and Aβ1-40 (n = 44) was analyzed. Kappa agreement of single biomarkers and Aβ1-42/Aβ1-40 was evaluated in an independent group of mild cognitive impairment (MCI) and dementia patients (n = 68). Next, established cutoffs were applied to a large real-world cohort of MCI subjects with follow-up data available (n = 647). Results: Cutoff values of Aβ1-42 and t-Tau were higher for CLEIA than for ELISA and similar for p181Tau. Spearman coefficients ranged between 0.81 for Aβ1-40 and 0.96 for p181TAU. Passing–Bablok analysis showed a systematic and proportional difference for all biomarkers but only systematic for Aβ1-40. Bland–Altman analysis showed an average difference between methods in favor of CLEIA. Kappa agreement for single biomarkers was good but lower for the Aβ1-42/Aβ1-40 ratio. Using the calculated cutoffs, we were able to stratify MCI subjects into four AT(N) categories. Kaplan–Meier analyses of AT(N) categories demonstrated gradual and differential dementia conversion rates (p = 9.815−27). Multivariate Cox proportional hazard models corroborated these findings, demonstrating that the proposed AT(N) classifier has prognostic value. AT(N) categories are only modestly influenced by other known factors associated with disease progression. Conclusions: We established CLEIA and ELISA internal cutoffs to discriminate AD patients from amyloid-negative SCD individuals. The results obtained by both methods are not interchangeable but show good agreement. CLEIA is a good and faster alternative to manual ELISA for providing AT(N) classification of our patients. AT(N) categories have an impact on disease progression. AT(N) classifiers increase the certainty of the MCI prognosis, which can be instrumental in managing real-world MCI subjects.  相似文献   
75.
2.6 GHz和4.9 GHz双频组网中,用户驻留策略取决于4.9 GHz小区的建设用途,根据不同需求有不同的策略和配置方案.本文基于实际网络经验,结合用户体验和业务需求,提出了5G双频网策略的配置建议.  相似文献   
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Influence of probiotic fermented milk product on the intestinal microbiota, hematological parameters and immune status of the experiment in vivo at Wistar rats was studied. It was shown, that entering of probiotic strains of Bifidobacterium bifidum 791, Bifidobacterium longum B-379M and Lactobacillus acidophilus NK1 u Streptococcus thermophilus in composition fermented milk products in the total quantity of 2,1 x 10(7) CFU/ sm3 in digestive tract within three weeks has a positive influence on the resident of colon microbiota. Significant increasing of population levels of Bifidobacterium, Enterobacteriaceae with normal biochemical properties, registered a strong tendency to increase the content of Lactobacteria, which led to a decreasing the number of potential pathogenic transient flora with pathogenic factors. Monitoring of body mass in experimental animals has shown that including of fermented milk product with probiotic strains in diet has a positive influence on the feed uptake. Probiotic properties of the product also have stimulated effect on the immune status of the rat: improvements in cell immunity (increasing the relative amount of T-helper cells, immuneregulatory index) and hematological parameters (increase  相似文献   
79.
BACKGROUND: The aim of this study was to examine how different environmental factors (temperature, solar radiation, and vapour‐pressure deficit [VPD]) influenced nutritional quality and flavour of cherry tomato fruits (Solanum lycopersicum L. cv. Naomi) grown in two types of experimental Mediterranean greenhouses: parral (low technology) and multispan (high technology). RESULTS: Fruits were sampled three times during 3 years (2004, 2005 and 2006): at the beginning, middle and end of the fruit production period. Values for temperature, solar radiation, and VPD peaked in the third sampling in both greenhouses; values were higher in the parral‐type greenhouse, triggering abiotic stress. This stress reduced the accumulation of lycopene and essential elements, augmenting the phytonutrient content and the antioxidant capacity of tomatoes. During the third sampling, sugars were increased while organic acid content diminished, producing tomatoes with a sweeter‐milder flavour. The parral greenhouse produced tomatoes with higher phenolic compounds and ascorbic acid contents, together with a greater antioxidant capacity, without showing differences in flavour parameters. CONCLUSION: The higher phytonutrients content and antioxidant activity during the environmental stress, more pronounced in parral than multispan greenhouse, together with the sweeter‐milder flavour, conferred a notable nutritional benefit, which considerably improved the nutritional and organoleptic quality of these tomatoes. Copyright © 2010 Society of Chemical Industry  相似文献   
80.
Bioavailability and biological properties of flavonoid glycosides can be improved after the enzymatic hydrolysis of specific glycosyl groups. In this study, we evaluate the antioxidant and antiproliferative potential of rutin after enzymatic hydrolysis performed by α-l-rhamnosidases (hesperidinase from Penicillium sp. and naringinase from Penicillium decumbens) previously heated at 70 °C for 30 min to inactivate the undesirable β-d-glucosidase activity. The highest in vitro antioxidant activity determined by DPPH radical scavenging was achieved with rutin hydrolyzed by hesperidinase. Rutin was predominantly bioconverted into quercetin-3-glucoside. There was no statistical difference between xanthine oxidase inhibition by rutin before and after hydrolysis. However, in vitro inhibitory activity against ten human tumor cell lines showed that hydrolyzed rutin exerted a more potent antiproliferative effect than quercetin and rutin on various cancer cell lines, specially glioma, and ovarian and breast adenocarcinomas. These results indicate that quercetin-3-glucoside could be a promising functional derivative obtained by rutin hydrolysis.  相似文献   
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