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101.
The development and proliferation of antibiotic resistance in pathogenic, commensal, and environmental microorganisms is a major public health concern. The extent to which human activities contribute to the maintenance of environmental reservoirs of antibiotic resistance is poorly understood. In the current study, wastewater treatment plants (WWTPs) were investigated as possible sources of tetracycline resistance via qualitative PCR and quantitative PCR (qPCR). Various WWTPs and two freshwater lakes were surveyed for the presence of an array of 10 tetracycline resistance determinants (tet(R)): tet(A)-(E), tet(G), tet(M), tet(O), tet(Q), tet(S). All WWTP samples contained more different types of tet(R) genes, as compared to the lake water samples. Gene copy numbers of tet(G) and tet(Q) in these samples were quantified via qPCR and normalized to both the volume of original sample and to the amount of DNA extracted per sample (a proxy for bacterial abundance). Concentrations of tet(Q) were found to be highest in wastewater influent while tet(G) concentrations were highest in activated sludge. Investigation of the effects of UV disinfection on wastewater effluent showed no reduction in the number of detectable tet(R) gene types. 相似文献
102.
Dong S Lu KQ Sun JQ Rudolph K 《Journal of intelligent material systems and structures》2006,17(6):543-552
Resistance exercise has been widely reported to have positive rehabilitation effects for patients with neuromuscular and orthopaedic conditions. This article presents prototypes of smart variable resistance exercise devices using magneto-rheological fluid dampers. An intelligent supervisory control for regulating the resistive force or torque of the device is developed, and is validated both numerically and experimentally. The device provides both isometric and isokinetic strength training for the human joints including knee, elbow, hip, and ankle. 相似文献
103.
Abstract: The utilization of a fuzzy aspect within data analysis attempts to move from a quantitative to a more qualitative investigative environment. As such, this may allow the more non‐quantitative researchers results they can use, based on sets of linguistic terms. In this paper an inductive fuzzy decision tree approach is utilized to construct a fuzzy‐rule‐based system for the first time in a biological setting. The specific biological problem considered attempts to identify the antecedents (conditions in the fuzzy decision rules) which characterize the length of song flight of the male sedge warbler when attempting to attract a mate. Hence, for a non‐quantitative investigator the resultant set of fuzzy rules allows an insight into the linguistic interpretation on the relationship between associated characteristics and the respective song flight duration. 相似文献
104.
105.
Katherine Jones 《International Journal of Network Management》1995,5(2):77-81
When a disaster recovery plan (DRP) is in place in a company, it is often solely for the mainframe; too often no attention is paid to the departmental distributed servers. 相似文献
106.
How virtual are we? Measuring virtuality and understanding its impact in a global organization 总被引:4,自引:0,他引:4
Katherine M. Chudoba Eleanor Wynn Mei Lu & Mary B. Watson-Manheim 《Information Systems Journal》2005,15(4):279-306
Abstract. Employees in global corporations are increasingly involved in 'virtual teams' on a regular basis. Conflicting definitions of virtuality make it hard to measure such things as how much virtual teaming occurs and how virtual teaming affects performance. As a consequence, it is hard to allocate funding and to design infrastructures and software to support this specific mode of working. Using the concept of discontinuities, or changes in expected conditions, we propose a virtuality index to assess how 'virtual' a given setting is. The discontinuities used include geography, time zone, organization, national culture, work practices, and technology. The index separately measures these aspects of virtuality and their effect on perceived team performance. Data collected at a large multinational corporation clustered into three overarching discontinuities: team distribution, workplace mobility, and variety of work practices. The study revealed that being distributed in and of itself had no impact on self-assessed team performance. Work practice predictability and sociability mitigated effects of working in discontinuous environments, while variety of practices (cultural and work process diversity) and employee mobility negatively impacted performance. 相似文献
107.
María López-Ruiz José Miguel Martínez Katherine Pérez Ana M. Novoa Aurelio Tobías Fernando G. Benavides 《Accident; analysis and prevention》2014
Objectives
To evaluate the impact of road safety interventions, including the penalty point system (PPS) and the reformed Spanish penal code (RPC), on traffic-related occupational injuries in Spain.Methods
The study design was an interrupted time-series with a comparison group. The study group had traffic-related, occupational injuries incurred during working and commuting hours; the comparison group had non-traffic-related injuries incurred at the work site. A negative binomial regression model was used to determine the relative risk (RR) of sustaining occupational injuries for the post-intervention periods compared to the non-intervention period.Results
Non-fatal, traffic-related injuries did not significantly change after the PPS and RPC implementations, except for those occurred in commuting hours, which increased significantly after the PPS. On the other hand, after the RPC, fatal, traffic-related injuries decreased significantly during working hours (0.79; 95%CI 0.65 to 0.97) and commuting hours (RR: 0.63; 95%CI:0.56 to 0.72), although fatal, non-traffic-related injuries also decreased at the work site.Conclusions
Road safety interventions did not clearly affect traffic-related occupational injuries in Spain. Specific occupational risk factors could influence the occurrence of those injuries. 相似文献108.
Aurelie Dos Santos Ning Lyu Alis Balayan Rob Knight Katherine Sun Zhuo Yuzhao Sun Jianjiang Xu Martha L. Funderburgh James L. Funderburgh Sophie X. Deng 《International journal of molecular sciences》2022,23(21)
In addition to their therapeutic potential in regenerative medicine, human corneal stromal stem cells (CSSCs) could serve as a powerful tool for drug discovery and development. Variations from different donors, their isolation method, and their limited life span in culture hinder the utility of primary human CSSCs. To address these limitations, this study aims to establish and characterize immortalized CSSC lines (imCSSC) generated from primary human CSSCs. Primary CSSCs (pCSSC), isolated from human adult corneoscleral tissue, were transduced with ectopic expression of hTERT, c-MYC, or the large T antigen of the Simian virus 40 (SV40T) to generate imCSSC. Cellular morphology, proliferation capacity, and expression of CSSCs specific surface markers were investigated in all cell lines, including TNFAIP6 gene expression levels in vitro, a known biomarker of in vivo anti-inflammatory efficacy. SV40T-overexpressing imCSSC successfully extended the lifespan of pCSSC while retaining a similar morphology, proliferative capacity, multilineage differentiation potential, and anti-inflammatory properties. The current study serves as a proof-of-concept that immortalization of CSSCs could enable a large-scale source of CSSC for use in regenerative medicine. 相似文献
109.
Chloroplasts are ancient organelles responsible for photosynthesis and various biosynthetic functions essential to most life on Earth. Many of these functions require tightly controlled regulatory processes to maintain homeostasis at the protein level. One such regulatory mechanism is the ubiquitin-proteasome system whose fundamental role is increasingly emerging in chloroplasts. In particular, the role of E3 ubiquitin ligases as determinants in the ubiquitination and degradation of specific intra-chloroplast proteins. Here, we highlight recent advances in understanding the roles of plant E3 ubiquitin ligases SP1, COP1, PUB4, CHIP, and TT3.1 as well as the ubiquitin-dependent segregase CDC48 in chloroplast function. 相似文献
110.
Jing Li Elisa Flix-Soriano Katherine R. Wright Hongtao Shen Lisa A. Baer Kristin I. Stanford Lian-Wang Guo 《International journal of molecular sciences》2022,23(18)
Obesity is increasing at epidemic rates across the US and worldwide, as are its co-morbidities, including type-2 diabetes and cardiovascular disease. Thus, targeted interventions to reduce the prevalence of obesity are of the utmost importance. The sigma-1 receptor (S1R) and sigma-2 receptor (S2R; encoded by Tmem97) belong to the same class of drug-binding sites, yet they are genetically distinct. There are multiple ongoing clinical trials focused on sigma receptors, targeting diseases ranging from Alzheimer’s disease through chronic pain to COVID-19. However, little is known regarding their gene-specific role in obesity. In this study, we measured body composition, used a comprehensive laboratory-animal monitoring system, and determined the glucose and insulin tolerance in mice fed a high-fat diet. Compared to Sigmar1+/+ mice of the same sex, the male and female Sigmar1−/− mice had lower fat mass (17% and 12% lower, respectively), and elevated lean mass (16% and 10% higher, respectively), but S1R ablation had no effect on their metabolism. The male Tmem97−/− mice exhibited 7% lower fat mass, 8% higher lean mass, increased volumes of O2 and CO2, a decreased respiratory exchange ratio indicating elevated fatty-acid oxidation, and improved insulin tolerance, compared to the male Tmem97+/+ mice. There were no changes in any of these parameters in the female Tmem97−/− mice. Together, these data indicate that the S1R ablation in male and female mice or the S2R ablation in male mice protects against diet-induced adiposity, and that S2R ablation, but not S1R deletion, improves insulin tolerance and enhances fatty-acid oxidation in male mice. Further mechanistic investigations may lead to translational strategies to target differential S1R/S2R regulations and sexual dimorphism for precision treatments of obesity. 相似文献