1,974 research outputs found
Red Skies in the Morning—Professional Ethics at the Dawn of Cloud Computing
The article evaluates risks to clients’ confidential and privileged information when lawyers or law firms store such information in any cloud computing “space” against the requirements of the Model Rules of Professional Conduct and the New York Rules of Professional Conduct. It also evaluates pertinent liability provisions of some of the more commonly used cloud computing services (Amazon.com and Google) against the lawyer’s responsibilities. An interesting portion covers the latest thinking from NIST on cloud computing benefits and risks
Understanding and modelling surface water-groundwater interactions
The main objective of the total project was to contribute to the incorpo-ration of uncertainty assessments in practical water resource decision making in South Africa. The companion report addresses more general issues of uncertainty and hydrological modelling, while this report con-centrates on the uncertainties in both understanding and modelling the interactions between surface water and groundwater. Since groundwa-ter routines were added into the widely used Pitman model in the early 2000s by both Prof Hughes and Mr Karim Sami, the approaches have come under a great deal of criticism mainly from the geohydrological community of specialists within South Africa. Arguably, a great deal of this criticism is based on misunderstandings of the intention of adding groundwater routines into an existing surface water model. It was stated quite clearly at the time that this approach was not seen as a replace-ment for existing detailed numerical approaches to groundwater model-ling. The intention was to create a scientific and practical tool that could be used to simulate the complete hydrological cycle at the catchment scale so that integrated water resources decision making could be better supported
Mutations in human immunodeficiency virus type 1 reverse transcriptase that make it sensitive to degradation by the viral protease in virions are selected against in patients
AbstractMutations in the thumb subdomain of reverse transcriptase (RT) of HIV-1 can cause this enzyme to be degraded in virions by the viral protease (PR). Many of these mutations confer a temperature-sensitive phenotype on RT and viral replication. The degradation of RT by PR appears to take place after Gag-Pol has been processed. We show here that mutations in other parts of RT, including the RNase H domain, can make RT PR-sensitive and temperature-sensitive. These data explain why some mutations in the RNase H domain, which had little or no effect on the polymerase activity of purified recombinant RT, had a profound effect on viral titer. Because the PR-sensitive phenotype significantly reduced viral titer, we previously suggested that these mutations would be selected against in patients. We also show that RT mutations that are known to confer a temperature sensitive phenotype are rarely found in the Stanford database
Mutations at position 184 of human immunodeficiency virus type-1 reverse transcriptase affect virus titer and viral DNA synthesis
AbstractMethionine at position 184 of human immunodeficiency virus type-1 (HIV-1) reverse transcriptase (RT) was changed to valine, isoleucine, threonine, or alanine in an HIV-1-based vector. The vectors were analyzed for replication capacity and for resistance to the nucleoside analog 2′,3′-dideoxy-3′thiacytidine (3TC) using a single-cycle assay. Viruses containing the valine or isoleucine mutations were highly resistant to 3TC and replicated almost as well as the wild-type virus. The virus containing the threonine mutation was resistant to 3TC, but replicated about 30% as well as the wild-type. The alanine mutation conferred partial resistance to 3TC, but replicated poorly. The amounts of viral DNA synthesized decreased in 3TC-treated cells when the cells were infected with wild-type virus and the M184A mutant. The effect of these mutations on the generation of the ends of the linear viral DNA was determined using the sequence of the 2-LTR circle junctions. The M184T mutation increased the proportion of 2-LTR circle junctions containing a tRNA insertion, suggesting that the mutation affected the RNase H activity of RT
Implementation and evaluation of the VA DPP clinical demonstration: protocol for a multi-site non-randomized hybrid effectiveness-implementation type III trial.
BackgroundThe Diabetes Prevention Program (DPP) study showed that lifestyle intervention resulted in a 58% reduction in incidence of type 2 diabetes among individuals with prediabetes. Additional large randomized controlled trials have confirmed these results, and long-term follow-up has shown sustained benefit 10-20 years after the interventions ended. Diabetes is a common and costly disease, especially among Veterans, and despite strong evidence supporting the feasibility of type 2 diabetes prevention, the DPP has not been widely implemented. The first aim of this study will evaluate implementation of the Veterans Affairs (VA) DPP in three VA medical centers. The second aim will assess weight and hemoglobin A1c (A1c) outcomes, and the third aim will determine the cost-effectiveness and budget impact of implementation of the VA DPP from a health system perspective.Methods/designThis partnered multi-site non-randomized systematic assignment study will use a highly pragmatic hybrid effectiveness-implementation type III mixed methods study design. The implementation and administration of the VA DPP will be funded by clinical operations while the evaluation of the VA DPP will be funded by research grants. Seven hundred twenty eligible Veterans will be systematically assigned to the VA DPP clinical demonstration or the usual care VA MOVE!® weight management program. A multi-phase formative evaluation of the VA DPP implementation will be conducted. A theoretical program change model will be used to guide the implementation process and assess applicability and feasibility of the DPP for VA. The Consolidated Framework for Implementation Research (CFIR) will be used to guide qualitative data collection, analysis, and interpretation of barriers and facilitators to implementation. The RE-AIM framework will be used to assess Reach, Effectiveness, Adoption, Implementation, and Maintenance of the VA DPP. Twelve-month weight and A1c change will be evaluated for the VA DPP compared to the VA MOVE!ProgramMediation analyses will be conducted to identify whether program design differences impact outcomes.DiscussionFindings from this pragmatic evaluation will be highly applicable to practitioners who are tasked with implementing the DPP in clinical settings. In addition, findings will determine the effectiveness and cost-effectiveness of the VA DPP in the Veteran population
A role for Snf2-related nucleosome-spacing enzymes in genome-wide nucleosome organization
The positioning of nucleosomes within the coding regions of eukaryotic genes is aligned with respect to transcriptional start sites. This organization is likely to influence many genetic processes, requiring access to the underlying DNA. Here, we show that the combined action of Isw1 and Chd1 nucleosome-spacing enzymes is required to maintain this organization. In the absence of these enzymes, regular positioning of the majority of nucleosomes is lost. Exceptions include the region upstream of the promoter, the +1 nucleosome, and a subset of locations distributed throughout coding regions where other factors are likely to be involved. These observations indicate that adenosine triphosphate-dependent remodeling enzymes are responsible for directing the positioning of the majority of nucleosomes within the Saccharomyces cerevisiae genome
Pregnancy insulin, glucose, and BMI contribute to birth outcomes in nondiabetic mothers.
OBJECTIVE: We investigated the effects of normal variations in maternal glycemia on birth size and other birth outcomes. RESEARCH DESIGN AND METHODS: Women in two unselected birth cohorts, one retrospective (n = 3,158) and one prospective (n = 668), underwent an oral glucose challenge at 28 weeks of gestation. In the retrospective study, glycemia was linked to routine birth records. In the prospective study, offspring adiposity was assessed by skinfold thickness from birth to age 24 months. RESULTS: In the retrospective study, within the nondiabetic range (2.1-7.8 mmol/l), each 1 mmol/l rise in the mother's 60-min glucose level was associated with a (mean +/- SEM) 2.1 +/- 0.8% (P = 0.006) rise in absolute risk of assisted vaginal delivery, a 3.4 +/- 0.8% (P 90th centile) was independently related to the mother's fasting glucose (odds ratio 2.61 per +1 mmol/l [95% CI 1.15-5.93]) and prepregnancy BMI (1.10 per +1 kg/m(2) [1.04-1.18]). The mother's higher fasting glycemia (P = 0.004), lower insulin sensitivity (P = 0.01), and lower insulin secretion (P = 0.02) were independently related to greater offspring adiposity at birth. During postnatal follow-up, the correlation between the mother's glycemia and offspring adiposity disappeared by 3 months, whereas prepregnancy BMI was associated with offspring adiposity that was only apparent at 12 and 24 months (both P < 0.05). CONCLUSIONS: Prepregnancy BMI, pregnancy glycemia, insulin sensitivity, and insulin secretion all contribute to offspring adiposity and macrosomia and may be separate targets for intervention to optimize birth outcomes and later offspring health
Practical quantum cryptography for secure free-space communications
Quantum cryptography is an emerging technology in which two parties may
simultaneously generate shared, secret cryptographic key material using the
transmission of quantum states of light. The security of these transmissions is
based on the inviolability of the laws of quantum mechanics and
information-theoretically secure post-processing methods. An adversary can
neither successfully tap the quantum transmissions, nor evade detection, owing
to Heisenberg's uncertainty principle. In this paper we describe the theory of
quantum cryptography, and the most recent results from our experimental
free-space system with which we have demonstrated for the first time the
feasibility of quantum key generation over a point-to-point outdoor atmospheric
path in daylight. We achieved a transmission distance of 0.5 km, which was
limited only by the length of the test range. Our results provide strong
evidence that cryptographic key material could be generated on demand between a
ground station and a satellite (or between two satellites), allowing a
satellite to be securely re-keyed on orbit. We present a feasibility analysis
of surface-to-satellite quantum key generation.Comment: 12 pages, 4 figure
Effectiveness of Home Health Care in Reducing Return to Hospital: Evidence from a Multi-hospital Study in the US
Background
Home health care, a commonly used bridge strategy for transitioning from hospital to home-based care, is expected to contribute to readmission avoidance efforts. However, in studies using disease-specific samples, evidence about the effectiveness of home health care in reducing readmissions is mixed. Objective
To examine the effectiveness of home health care in reducing return to hospital across a diverse sample of patients discharged home following acute care hospitalization. Research design
Secondary analysis of a multi-site dataset from a study of discharge readiness assessment and post-discharge return to hospital, comparing matched samples of patients referred and not referred for home health care at the time of hospital discharge. Setting
Acute care, Magnet-designated hospitals in the United States Participants
The available sample (n = 18,555) included hospitalized patients discharged from medical-surgical units who were referred (n = 3,579) and not referred (n = 14,976) to home health care. The matched sample included 2767 pairs of home health care and non- home health care patients matched on patient and hospitalization characteristics using exact and Mahalanobis distance matching. Methods
Unadjusted t-tests and adjusted multinomial logit regression analyses to compare the occurrence of readmissions and Emergency Department/Observation visits within 30 and 60-days post-discharge. Results
No statistically significant differences in readmissions or Emergency Department /Observation visits between home health care and non-home health care patients were observed. Conclusions
Home health care referral was not associated with lower rates of return to hospital within 30 and 60 days in this US sample matched on patient and clinical condition characteristics. This result raises the question of why home health care services did not produce evidence of lower post-discharge return to hospital rates. Focused attention by home health care programs on strategies to reduce readmissions is needed
North to south: ecosystem features determine seagrass community response to sea otter foraging
We compared sea otter recovery in California (CA) and British Columbia (BC) to determine how key ecosystem properties shape top-down effects in seagrass communities. Potential ecosystem drivers of sea otter foraging in CA and BC seagrass beds that we examined include the role of coastline complexity and environmental stress on sea otter effects. In BC, we found greater species richness across seagrass trophic assemblages. Furthermore, Cancer spp. crabs, an important link in the seagrass trophic cascade observed in CA, was less common. Additionally, the more recent reintroduction of sea otters, more complex coastline, and reduced environmental stress in BC seagrass habitats supported the hypothesis that sea otter foraging pressure is currently reduced in more northern latitudes. In order to manage the ecosystem features that lead to regional differences in top predator effects in seagrass communities, we review our findings, their spatial and temporal constraints, and present a social-ecological framework for future re- search
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