797 research outputs found
Message Latency Characterization of a Distributed Live, Virtual, Constructive Simulation Environment
A distributed test environment incorporating Live, Virtual, Constructive, (LVC) concepts was developed to execute standalone and integrated simulations and flight-tests that support unmanned aircraft research for NASAs Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) Project. The LVC components form the core infrastructure that supports simulation of UAS operations by integrating live and virtual aircraft in a realistic air traffic environment. This LVC infrastructure enables efficient testing by leveraging the use of existing distributed assets. The LVC concepts used for the UAS in the NAS project include live aircraft, flight simulators, and virtual air traffic control assets operating at facilities distributed across multiple NASA Centers. With a distributed network, however, there is a concern that message latency could impact the realism of a simulation and its data. The latencies associated with sending data among these distributed facilities were, therefore, measured to ensure that they fall within acceptable parameters. Several live and virtual test assets were integrated into the LVC infrastructure including NASA Armstrongs Ikhana MQ-9 unmanned aircraft, NASA Glenns S3-B manned aircraft, and the B747 flight simulator at NASA Ames. Average latencies from 100 to 150 milliseconds were observed between the LVC System running at NASA Ames and each of the participating NASA Centers under a light-to-moderate (fifty aircraft) traffic sample
Observation of surface states on heavily indium doped SnTe(111), a superconducting topological crystalline insulator
The topological crystalline insulator tin telluride is known to host
superconductivity when doped with indium (SnInTe), and for low
indium contents () it is known that the topological surface states are
preserved. Here we present the growth, characterization and angle resolved
photoemission spectroscopy analysis of samples with much heavier In doping (up
to ), a regime where the superconducting temperature is increased
nearly fourfold. We demonstrate that despite strong p-type doping, Dirac-like
surface states persist
Monitoring and characterization of bacterial populations of two biological air filters during the start up phase
[Abstract] This study aimed to monitor and characterize bacterial populations of two biological air filters during their start up phase (four months). The main objective of this work was to assess the potentiality of a microbiological approach to better understand the evolution of the bacterial populations within biofilters and therefore help to select biomass carrier media. The two biological filters were operated at full-scale (480 m3), filled with organic materials and dedicated to the removal of ammonia and Volatile Organic Compounds (VOCs). The first step of the work consisted in developing an extraction method for the biomass fixed on the solid supports. The second step investigated biofilters’ microbial ecology using molecular tools: DAPI (4,6-DiAmino-2- PhenylIndole), TVC (Total Viable Counts), FISH (Fluorescent In Situ Hybridization) and SSCP (Single Strand Conformation Polymorphism). The findings of the experiments did not show a significant evolution of total bacterial concentrations in biofilms of both biological filters during their start up phase. However, SSCP data analysis underlined important variations in the composition of bacterial populations. Finally, examination of the results highlighted the interest to inoculate organic media in order to reduce the acclimation time of microbial populations
Water adsorption on vanadium oxide thin films in ambient relative humidity.
In this work, ambient pressure x-ray photoelectron spectroscopy (APXPS) is used to study the initial stages of water adsorption on vanadium oxide surfaces. V 2p, O 1s, C 1s, and valence band XPS spectra were collected as a function of relative humidity in a series of isotherm and isobar experiments. Experiments were carried out on two VO2 thin films on TiO2 (100) substrates, prepared with different surface cleaning procedures. Hydroxyl and molecular water surface species were identified, with up to 0.5 ML hydroxide present at the minimum relative humidity, and a consistent molecular water adsorption onset occurring around 0.01% relative humidity. The work function was found to increase with increasing relative humidity, suggesting that surface water and hydroxyl species are oriented with the hydrogen atoms directed away from the surface. Changes in the valence band were also observed as a function of relative humidity. The results were similar to those observed in APXPS experiments on other transition metal oxide surfaces, suggesting that H2O-OH and H2O-H2O surface complex formation plays an important role in the oxide wetting process and water dissociation. Compared to polycrystalline vanadium metal, these vanadium oxide films generate less hydroxide and appear to be more favorable for molecular water adsorption
Modulation of the activity of sp transcription factors by mithramycin analogues as a new strategy for treatment of metastatic prostate cancer
Deregulated activity of transcription factors (TFs) of the Sp/KLF family, like Sp1, Sp3 and Sp4, and consequent over-expression of Sp-regulated genes occur frequently in human cancers. This provides the rationale for development of inhibitors of Sp TFs as cancer therapeutics. Mithramycin A (MTM-A) is a natural polyketide that binds GC-rich DNA sequences, inhibits activity of Sp TFs and exhibits potent antitumor activity in experimental systems. However, clinical use of MTM-A is limited by the severe toxicity of the compound. Here, we studied two MTM-A analogues, which had been generated by genetically engineering of the MTM-A biosynthetic pathway, and evaluated their activity in human prostate cancer in cell cultures and mouse models. The compounds, named MTM-SDK and MTM-SK, were highly effective in vitro inhibiting proliferation of prostate cancer cells and transcription of Sp-regulated genes by blocking binding of Sp proteins to the gene promoters When administered to mice, both compounds were well tolerated with maximum tolerated doses of MTM-SDK and MTM-SK, respectively, 4- and 32- fold higher than MTM-A. After systemic administration, both compounds were cleared rapidly from the bloodstream but maintained plasma levels well above the active concentrations required in vitro for inhibition of Sp TF activity and cell proliferation. Consistently, MTM-SDK and MTM-SK inhibited transcription of Sp-regulated genes in prostate tumor xenografts and exhibited potent antitumor activity in subcutaneous and metastatic tumor xenograft models with no or minimal toxicity. Taken together, these data indicate that MTM-SDK and MTM-SK possess significantly improved pharmacological and toxicological properties compared to MTM-A and represent promising drugs for treatment of advanced prostate cancer
Water first aid is beneficial in humans post-burn: evidence from a bi-national cohort study
Introduction: Reported first aid application, frequency and practices around the world vary greatly. Based primarily on animal and observational studies, first aid after a burn injury is considered to be integral in reducing scar and infection, and the need for surgery. The current recommendation for optimum first aid after burn is water cooling for 20 minutes within three hours. However, compliance with this guideline is reported as poor to moderate at best and evidence exists to suggest that overcooling can be detrimental. This prospective cohort study of a binational burn patient registry examined data collected between 2009 and 2012. The aim of the study was to quantify the magnitude of effects of water cooling first aid after burn on indicators of burn severity in a large human cohort.
Method: The data for the analysis was provided by the Burn Registry of Australia and New Zealand (BRANZ). The application of first aid cooling prior to admission to a dedicated burn service, was analysed for its influence on four outcomes related to injury severity. The patient related outcomes were whether graft surgery occurred, and death while the health system (cost) outcomes included total hospital length of stay and admission to ICU. Robust regression analysis using bootstrapped estimation adjusted using a propensity score was used to control for confounding and to estimate the strength of association with first aid. Dose-response relationships were examined to determine associations with duration of first aid. The influence of covariates on the impact of first aid was assessed.
Results: Cooling was provided before Burn Centre admission for 68% of patients, with at least twenty minutes duration for 46%. The results indicated a reduction in burn injury severity associated with first aid. Patients probability for graft surgery fell by 0.070 from 0.537 (13% reduction) (p = 0.014). The probability for ICU admission fell by 0.084 from 0.175 (48% reduction) (p (p = 0.001). All outcomes except death showed a dose-response relationship with the duration of first aid. The size of burn and age interacted with many of the relationships between first aid and outcome and these are described and discussed.
Discussion & Conclusion: This study suggests that there are significant patient and health system benefits from cooling water first aid, particularly if applied for up to 20 minutes. The results of this study estimate the effect size of post-burn first aid and confirm that efforts to promote first aid knowledge are not only warranted, but provide potential cost savings
Health literacy, health status, and healthcare utilization of Taiwanese adults: results from a national survey
Abstract Background Low health literacy is considered a worldwide health threat. The purpose of this study is to assess the prevalence and socio-demographic covariates of low health literacy in Taiwanese adults and to investigate the relationships between health literacy and health status and health care utilization. Methods A national survey of 1493 adults was conducted in 2008. Health literacy was measured using the Mandarin Health Literacy Scale. Health status was measured based on self-rated physical and mental health. Health care utilization was measured based on self-reported outpatient clinic visits, emergency room visits, and hospitalizations. Results Approximately thirty percent of adults were found to have low (inadequate or marginal) health literacy. They tended to be older, have fewer years of schooling, lower household income, and reside in less populated areas. Inadequate health literacy was associated with poorer mental health (OR, 0.57; 95% CI, 0.35-0.91). No association was found between health literacy and health care utilization even after adjusting for other covariates. Conclusions Low (inadequate and marginal) health literacy is prevalent in Taiwan. High prevalence of low health literacy is not necessarily indicative of the need for interventions. Systematic efforts to evaluate the impact of low health literacy on health outcomes in other countries would help to illuminate features of health care delivery and financing systems that may mitigate the adverse health effects of low health literacy.http://deepblue.lib.umich.edu/bitstream/2027.42/78252/1/1471-2458-10-614.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78252/2/1471-2458-10-614.pdfPeer Reviewe
A randomised comparison evaluating changes in bone mineral density in advanced prostate cancer: luteinising hormone-releasing hormone agonists versus transdermal oestradiol.
BACKGROUND: Luteinising hormone-releasing hormone agonists (LHRHa), used as androgen deprivation therapy (ADT) in prostate cancer (PCa) management, reduce serum oestradiol as well as testosterone, causing bone mineral density (BMD) loss. Transdermal oestradiol is a potential alternative to LHRHa. OBJECTIVE: To compare BMD change in men receiving either LHRHa or oestradiol patches (OP). DESIGN, SETTING, AND PARTICIPANTS: Men with locally advanced or metastatic PCa participating in the randomised UK Prostate Adenocarcinoma TransCutaneous Hormones (PATCH) trial (allocation ratio of 1:2 for LHRHa:OP, 2006-2011; 1:1, thereafter) were recruited into a BMD study (2006-2012). Dual-energy x-ray absorptiometry scans were performed at baseline, 1 yr, and 2 yr. INTERVENTIONS: LHRHa as per local practice, OP (FemSeven 100μg/24h patches). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was 1-yr change in lumbar spine (LS) BMD from baseline compared between randomised arms using analysis of covariance. RESULTS AND LIMITATIONS: A total of 74 eligible men (LHRHa 28, OP 46) participated from seven centres. Baseline clinical characteristics and 3-mo castration rates (testosterone ≤1.7 nmol/l, LHRHa 96% [26 of 27], OP 96% [43 of 45]) were similar between arms. Mean 1-yr change in LS BMD was -0.021g/cm(3) for patients randomised to the LHRHa arm (mean percentage change -1.4%) and +0.069g/cm(3) for the OP arm (+6.0%; p<0.001). Similar patterns were seen in hip and total body measurements. The largest difference between arms was at 2 yr for those remaining on allocated treatment only: LS BMD mean percentage change LHRHa -3.0% and OP +7.9% (p<0.001). CONCLUSIONS: Transdermal oestradiol as a single agent produces castration levels of testosterone while mitigating BMD loss. These early data provide further supporting evidence for the ongoing phase 3 trial. PATIENT SUMMARY: This study found that prostate cancer patients treated with transdermal oestradiol for hormonal therapy did not experience the loss in bone mineral density seen with luteinising hormone-releasing hormone agonists. Other clinical outcomes for this treatment approach are being evaluated in the ongoing PATCH trial. TRIAL REGISTRATION: ISRCTN70406718, PATCH trial (ClinicalTrials.gov NCT00303784)
The association of health literacy with adherence in older 2 adults, and its role in interventions: a systematic meta-review
Background: Low health literacy is a common problem among older adults. It is often suggested to be associated with poor adherence. This suggested association implies a need for effective adherence interventions in low health literate people. However, previous reviews show mixed results on the association between low health literacy and poor adherence. A systematic meta-review of systematic reviews was conducted to study the association between health literacy and adherence in adults above the age of 50. Evidence for the effectiveness of adherence interventions among adults in this older age group with low health literacy was also explored. Methods: Eight electronic databases (MEDLINE, ERIC, EMBASE, PsycINFO, CINAHL, DARE, the Cochrane Library, and Web of Knowledge) were searched using a variety of keywords regarding health literacy and adherence. Additionally, references of identified articles were checked. Systematic reviews were included if they assessed the association between health literacy and adherence or evaluated the effectiveness of interventions to improve adherence in adults with low health literacy. The AMSTAR tool was used to assess the quality of the included reviews. The selection procedure, data-extraction, and quality assessment were performed by two independent reviewers. Seventeen reviews were selected for inclusion. Results: Reviews varied widely in quality. Both reviews of high and low quality found only weak or mixed associations between health literacy and adherence among older adults. Reviews report on seven studies that assess the effectiveness of adherence interventions among low health literate older adults. The results suggest that some adherence interventions are effective for this group. The interventions described in the reviews focused mainly on education and on lowering the health literacy demands of adherence instructions. No conclusions could be drawn about which type of intervention could be most beneficial for this population. Conclusions: Evidence on the association between health literacy and adherence in older adults is relatively weak. Adherence interventions are potentially effective for the vulnerable population of older adults with low levels of health literacy, but the evidence on this topic is limited. Further research is needed on the association between health literacy and general health behavior, and on the effectiveness of interventions
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