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21.
A Three‐wave Study of Antecedents of Work–Family Enrichment: The Roles of Social Resources and Affect 下载免费PDF全文
Oi Ling Siu Arnold B. Bakker Paula Brough Chang‐qin Lu Haijiang Wang Thomas Kalliath Michael O'Driscoll Jiafang Lu Carolyn Timms 《Stress and health》2015,31(4):306-314
On the basis of conservation of resources theory (Hobfoll, 1989 ) and the resource‐gain‐development perspective (Wayne, Grzywacz, Carlson, & Kacmar, 2007 ), this paper examines the differential impact of specific social resources (supervisory support and family support) on specific types of affect (job satisfaction and family satisfaction, respectively), which, in turn, influence work‐to‐family enrichment and family‐to‐work enrichment, respectively. A sample of 276 Chinese workers completed questionnaires in a three‐wave survey. The model was tested with structural equation modelling. Job satisfaction at time 2 partially mediated the relationship between time 1 supervisory support and time 3 work‐to‐family enrichment (capital), and the effect of supervisory support on work‐to‐family enrichment (affect) was fully mediated by job satisfaction. Family satisfaction at time 2 fully mediated the relationship between time 1 family support and time 3 family‐to‐work enrichment (affect, efficiency). Implications for theory, practice and future research are discussed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Fiete Boehning Daniel Timms Po‐Lin Hsu Thomas Schmitz‐Rode Ulrich Steinseifer 《Artificial organs》2013,37(10):913-920
Rotary blood pumps (RBPs) have demonstrated considerable promise while treating heart failure patients, such that they are being placed at an earlier stage of the disease. These devices may therefore be required to operate for prolonged durations which yields the need for RBPs exhibiting high durability, reliability, and blood compatibility. Noncontacting bearings, utilizing magnetic and/or hydrodynamic suspension techniques, appear to provide a suitable solution to these challenges. Hydrodynamic suspension has the advantage that it does not need feedback control systems. Among various hydrodynamic bearing types, the circular journal bearing has the particular benefit of easy manufacturing. This study presents methods to evaluate the performance of short (length to diameter ratio <1) circular hydrodynamic journal bearings (HJBs) for RBPs. Analytical calculations with specific boundary conditions are presented to predict the rotor's eccentricity under equilibrium states and thus the related performance parameters such as load capacity, power loss, and shear rates. These results and boundary conditions were confirmed experimentally in a specially designed test set‐up. The bearing performance was found to correlate to analytical solutions using the full Sommerfeld boundary condition instead of the half Sommerfeld condition conventionally used for such applications. Geometrical and operational parameter variations showed that HJB designs with a short Sommerfeld Number SS >0.02 can provide sufficient fluid film thicknesses and low shear rates. The measurements were further used to evaluate the bearings' stability. The estimation of the stability threshold drawn in relation to a modified stability index and the equilibrium eccentricity of the rotor allows the prediction of stability for short circular HJB designs under full Sommerfeld condition. 相似文献
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Robert F. Salamonsen Vincent Pellegrino John F. Fraser Kate Hayes Daniel Timms Nigel Hamilton Lovell Christopher Hayward 《Artificial organs》2013,37(8):695-703
This multicenter study examines in detail the spontaneous increase in pump flow at fixed speed that occurs in exercise. Eight patients implanted with the VentrAssist rotary blood pump were subjected to maximal and submaximal cycle ergometry studies, the latter being completed with patients supine and monitored with right heart catheter and echocardiography. Maximal exercise studies conducted in each patient at three different pump speeds on separate days established initially the magnitude and consistency of increases in pump flow that correlated well with changes in heart rate. However, there was considerable variation, coefficients of variation for mean heart rate and pump flow being 47.9 and 49.3%, respectively. Secondly, these studies indicated that increasing pump flows caused significant improvements in maximal exercise capacity. An increase of 2.1 L/min (35%) in maximum blood flow caused 12 W (16%) further increase in achievable work, 1.26 (9.3%) mL/kg/min in maximal oxygen uptake, and 2.3 (23%) mL/kg/min in anaerobic threshold. Mean increases in lactate were 0.85 mm (24%), but mean B‐type natiuretic peptide fell by 126 mm , (?78%). From submaximal supine exercise studies, multiple linear regression of pump flow on factors thought to underlie the spontaneous increase in pump flow indicated that it was associated with increases in heart rate (P = 0.039), pressure gradient across the left ventricle (P = 0.032), and right atrial pressure (P = 0.003). These changes have implications for the recently reported Starling‐like controller for pump flow based on pump pulsatility values, which emulates the Starling curve relating pump output to left ventricular preload. Unmodified, the controller would not permit the full benefits of this effect to be afforded to patients implanted with rotary blood pumps. A modification to the pump control algorithm is proposed to eliminate this problem 相似文献
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Mark D Stewart Diana Merino Vega Rebecca C Arend Jonathan F Baden Olena Barbash Nike Beaubier Grace Collins Tim French Negar Ghahramani Patsy Hinson Petar Jelinic Matthew J Marton Kimberly McGregor Jerod Parsons Lakshman Ramamurthy Mark Sausen Ethan S Sokol Albrecht Stenzinger Hillary Stires Kirsten M Timms Diana Turco Iris Wang J Andrew Williams Elaine Wong-Ho Jeff Allen 《The oncologist》2022,27(3):167
BackgroundHomologous recombination deficiency (HRD) is a phenotype that is characterized by the inability of a cell to effectively repair DNA double-strand breaks using the homologous recombination repair (HRR) pathway. Loss-of-function genes involved in this pathway can sensitize tumors to poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors and platinum-based chemotherapy, which target the destruction of cancer cells by working in concert with HRD through synthetic lethality. However, to identify patients with these tumors, it is vital to understand how to best measure homologous repair (HR) status and to characterize the level of alignment in these measurements across different diagnostic platforms. A key current challenge is that there is no standardized method to define, measure, and report HR status using diagnostics in the clinical setting.MethodsFriends of Cancer Research convened a consortium of project partners from key healthcare sectors to address concerns about the lack of consistency in the way HRD is defined and methods for measuring HR status.ResultsThis publication provides findings from the group’s discussions that identified opportunities to align the definition of HRD and the parameters that contribute to the determination of HR status. The consortium proposed recommendations and best practices to benefit the broader cancer community.ConclusionOverall, this publication provides additional perspectives for scientist, physician, laboratory, and patient communities to contextualize the definition of HRD and various platforms that are used to measure HRD in tumors. 相似文献
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Comparison of Chlamydia psittaci isolates by restriction endonuclease and DNA probe analyses. 总被引:7,自引:1,他引:7 下载免费PDF全文
DNAs from eight Chlamydia psittaci isolates (koala conjunctivitis, avian psittacosis, avian ornithosis, ovine abortion, ovine polyarthritis, sporadic bovine encephalomyelitis, and feline conjunctivitis) and one Chlamydia trachomatis isolate (lymphogranuloma venereum) were compared by restriction endonuclease and DNA probe analyses. Digestion with HindIII yielded a series of discrete fragments which allowed the differentiation of most isolates. A gene probe, pFEN207, which encodes the chlamydia-specific component of the lipopolysaccharide group antigen was used in Southern hybridizations. The probe was chlamydia specific and hybridized to a single BamHI fragment and multiple HindIII fragments in each isolate. The variation in size of the hybridizing fragments allowed easy differentiation of the isolates and may eventually lead to a meaningful subgrouping of the diverse group of disease agents presently included in the species C. psittaci. 相似文献
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AM Innes KM Boycott EG Puffenberger D Redl IM MacDonald AE Chudley C Beaulieu R Perrier T Gillan A Wade JS Parboosingh 《Clinical genetics》2010,78(5):424-431
Innes AM, Boycott KM, Puffenberger EG, Redl D, MacDonald IM, Chudley AE, Beaulieu C, Perrier R, Gillan T, Wade A, Parboosingh JS. A founder mutation in BBS2 is responsible for Bardet‐Biedl syndrome in the Hutterite population: utility of SNP arrays in genetically heterogeneous disorders. Bardet‐Biedl syndrome (BBS) is a multisystem genetically heterogeneous disorder, the clinical features of which are largely the consequence of ciliary dysfunction. BBS is typically inherited in an autosomal recessive fashion, and mutations in at least 14 genes have been identified. Here, we report the identification of a founder mutation in the BBS2 gene as the cause for the increased incidence of this developmental disorder in the Hutterite population. To ascertain the Hutterite BBS locus, we performed a genome‐wide single nucleotide polymorphism (SNP) analysis on a single patient and his three unaffected siblings from a Hutterite family. The analysis identified two large SNP blocks that were homozygous in the patient but not in his unaffected siblings, one of these regions contained the BBS2 gene. Sequence analysis and subsequent RNA studies identified and confirmed a novel splice site mutation, c.472‐2A>G, in BBS2. This mutation was also found in homozygous form in three subsequently studied Hutterite BBS patients from two different leuts, confirming that this is a founder mutation in the Hutterite population. Further studies are required to determine the frequency of this mutation and its role, if any, in the expression of other ciliopathies in this population. 相似文献