Finding Large Independent Sets in Line of Sight Networks

Line of Sight (LoS) networks provide a model of wireless communication which incorporates visibility constraints. Vertices of such networks can be embedded in finite d-dimensional grids of size n, and two vertices are adjacent if they share a line of sight and are at distance less tha

Vertex-Connectivity for Node Failure Identification in Boolean Network Tomography

In this paper we study the node failure identification problem in undirected graphs by means of Boolean Network Tomography. We argue that vertex connectivity plays a central role. We show tight bounds on the maximal identifiability in a particular class of graphs, the Line of Sight networks. We prove slightly weaker bounds on arbitrary networks. Finally we initiate the study of maximal identifiability in random networks. We focus on two models: the classical Erdős-Rényi model, and that of Random Regular graphs. The framework proposed in the paper allows a probabilistic analysis of the identifiability in random networks giving a tradeoff between the number of monitors to place and the maximal identifiability

Effects of glucose and lactate on <em>Streptococcus </em><em>mutans </em>abundance in a novel multispecies oral biofilm model

The oral microbiome plays an important role in protecting oral health. Here, we established a controlled mixed-species in vitro biofilm model and used it to assess the impact of glucose and lactate on the ability of Streptococcus mutans, an acidogenic and aciduric species, to compete with commensal oral bacteria. A chemically defined medium was developed that supported the growth of S. mutans and four common early colonizers of dental plaque: Streptococcus gordonii, Actinomyces oris, Neisseria subflava, and Veillonella parvula. Biofilms containing the early colonizers were developed in a continuous flow bioreactor, exposed to S. mutans, and incubated for up to 7 days. The abundance of bacteria was estimated by quantitative polymerase chain reaction (qPCR). At high glucose and high lactate, the pH in bulk fluid rapidly decreased to approximately 5.2, and S. mutans outgrew other species in biofilms. In low glucose and high lactate, the pH remained above 5.5, and V. parvula was the most abundant species in biofilms. By contrast, in low glucose and low lactate, the pH remained above 6.0 throughout the experiment, and the microbial community in biofilms was relatively balanced. Fluorescence in situ hybridization confirmed that all species were present in the biofilm and the majority of cells were viable using live/dead staining. These data demonstrate that carbon source concentration is critical for microbial homeostasis in model oral biofilms. Furthermore, we established an experimental system that can support the development of computational models to predict transitions to microbial dysbiosis based on metabolic interactions. 38376204</strong

Understanding the role of graphene on the moisture absorption in graphene/polymer nanocomposites

This study focuses on understanding the effect of graphene, when introduced in epoxy systems, on the overall moisture absorption capacity and behaviour of epoxy resin composites subjected to hydrothermal conditions. Pristine epoxy resin and epoxy resin incorporating functionalised and unfunctionalised graphene reinforcement were manufactured and exposed to 90°C purified water for 30 days. The flexural and tensile properties were observed for both unaged and aged specimens. A lower moisture absorption capacity was observed for graphene enhanced specimens as opposed to pristine epoxy resin, which suggests the potential of graphene as a barrier to moisture ingress. Despite the lower mass gain observed, the performance of the nano-filled resins exhibits a larger reduction in properties following water absorption

Physician Use of Advance Care Planning Discussions in a Diverse Hospitalized Population

Two decades after the Patient Self Determination Act it is unknown how often physicians have advance care planning (ACP) discussions with hospitalized patients. The objective of this study is to investigate use of ACP discussions in a multi-ethnic, multi-lingual hospitalized population. Cross-sectional communication study of hospitalized patients. The Participants are 369 patients at one urban county hospital and one academic medical center. Interventions are not applicable. Participants were asked at baseline and a post-discharge interview whether hospital physicians had discussed either (a) what type of treatment they would want if they could not make decisions for themselves or (b) whether they would want cardiopulmonary resuscitation if needed. We compared patient characteristics for those who did and did not have an ACP discussion. Only 151 (41%) participants reported an ACP discussion. Rates of ACP were low across ethnic, language, education and age groups. In a multivariate model, scoring higher on a co-morbidity scale was associated with higher odds of reporting having had an ACP discussion during hospitalization; this finding remained after adjusting for time period and site of data collection. Multiethnic, multi-lingual hospitalized patients reported low rates of ACP discussions with their physicians regardless of ethnicity, English proficiency, education level or age

Costs of Measuring Outcomes of Acute Hospital Care in a Longitudinal Outcomes Measurement System

It is widely acknowledged that the measurement of outcomes of care and the comparison of outcomes over time within health care providers and risk-adjusted comparisons among providers are important parts of improving quality and cost-effectiveness of care. However, few studies have assessed the costs of measuring outcomes of care. We sought to evaluate the personnel and financial resources spent for a prospective assessment of outcomes of acute hospital care by health professionals in internal medicine. The study included 15 primary care hospitals participating in a longitudinal outcomes measurement program and 2005 patients over an assessment period with an average duration of 6 months. Each hospital project manager participated in a previously-tested structured 30-minute telephone interview. Outcome measures include time spent by the individual job titles in implementing and running the outcomes measurement program. Job-title-specific times were used to calculate costs from the hospitals' perspective. One-time costs (C2132 + 1352) and administrative costs (95 97 per week) varied substantially. Costs per patient were fairly stable at around 20. We estimated that the total cost for each hospital to assess outcomes of care for accreditation (10 tracer diagnoses over 6 months) would be 9700 and that continuous monitoring of outcomes (5 tracer diagnoses) would cost 12,400 per year. This study suggests that outcomes of acute hospital care can be assessed with limited resources and that standardized training programs would reduce variability in overall costs. This study should help hospital decision makers to estimate the necessary funding for outcomes measurement initiatives

Clinical course, costs and predictive factors for response to treatment in carpal tunnel syndrome: The PALMS study protocol

Background Carpal tunnel syndrome (CTS) is the most common neuropathy of the upper limb and a significant contributor to hand functional impairment and disability. Effective treatment options include conservative and surgical interventions, however it is not possible at present to predict the outcome of treatment. The primary aim of this study is to identify which baseline clinical factors predict a good outcome from conservative treatment (by injection) or surgery in patients diagnosed with carpal tunnel syndrome. Secondary aims are to describe the clinical course and progression of CTS, and to describe and predict the UK cost of CTS to the individual, National Health Service (NHS) and society over a two year period. Methods/Design In this prospective observational cohort study patients presenting with clinical signs and symptoms typical of CTS and in whom the diagnosis is confirmed by nerve conduction studies are invited to participate. Data on putative predictive factors are collected at baseline and follow-up through patient questionnaires and include standardised measures of symptom severity, hand function, psychological and physical health, comorbidity and quality of life. Resource use and cost over the 2 year period such as prescribed medications, NHS and private healthcare contacts are also collected through patient self-report at 6, 12, 18 and 24 months. The primary outcome used to classify treatment success or failures will be a 5-point global assessment of change. Secondary outcomes include changes in clinical symptoms, functioning, psychological health, quality of life and resource use. A multivariable model of factors which predict outcome and cost will be developed. Discussion This prospective cohort study will provide important data on the clinical course and UK costs of CTS over a two-year period and begin to identify predictive factors for treatment success from conservative and surgical interventions

Chronic toxicity and carcinogenicity testing in the Sprague–Dawley rat of a prospective insect repellent (KBR 3023) using the dermal route of exposure

Abstract The chronic toxicology and carcinogenic potential of 1-(1-methyl-propoxycarbonyl)-2-(2-hydroxyethyl)-piperidine (KBR 3023), a prospective new insect repellent intended for human use, was studied in rats using the dermal route of application. Relying upon the toxicology profile that emerged in the subchronic rat bioassay that was conducted using dermally applied dosages of 0, 80, 200, 500 and 1000 mg KBR 3023/kg body wt/day, it was determined, in concert with the Environmental Protection Agency (EPA), that dermally applied dosages of 0, 50, 100 or 200 mg KBR 3023/kg body wt/day would be used in the conduction of all definitive forms of subchronic, chronic, and lifetime descriptive testing performed with the chemical. Using this testing approach, the specific results of this 2-year study are as follows. All in-life parameters, which included body weight, food consumption, clinical observations, survival, ophthalmology, clinical chemistry, hematology, and urinalysis, were unaffected by exposure to KBR 3023. Similarly, postmortem analyses, which included organ weights and gross pathology, were also unchanged following exposure to KBR 3023. Histopathology at the dose site/skin was characterized by a pattern of acanthosis and/or hyperkeratosis across all doses in 1-and 2-year rats. Beyond the dosing site, cystic degeneration of the liver was described in 2-year 200-mg KBR 3023/kg body wt/day males. No other compound-related non-dosing site lesion was identified at any dose tested. No evidence of a compound-induced neoplasia was suggested in this bioassay. © 1999 Elsevier Science Ireland Ltd. All rights reserved

Independent Sets in Restricted Line of Sight Networks

Line of Sight (LoS) networks were designed to model wireless networks in settings which may contain obstacles restricting visibility of sensors. A grap

An association between anti-platelet drug use and reduced cancer prevalence in diabetic patients: results from the Vermont Diabetes Information System Study

<p>Abstract</p> <p>Background</p> <p>Diabetes is associated with an increased risk of several malignancies. Both diabetic patients and patients with cancer have an increase in platelet reactivity and platelet activation has recently emerged as a potential mediator of cancer progression. Drug therapies, such as aspirin, that reduce platelet reactivity reduce both cardiovascular and cancer risk.</p> <p>Methods</p> <p>We performed a cross-sectional analysis to assess the association between history of cancer and current anti-platelet drug use in a primary care population of adults with diabetes enrolled in the Vermont Diabetes Information System.</p> <p>Results</p> <p>Self-reported characteristics, medical history, and a complete medication list were recorded on 1007 diabetic adults. Fifty percent of diabetic patients used an anti-platelet drug. In unadjusted analysis, no association was seen between anti-platelet drug use and cancer history (OR = 0.93; <it>P </it>= .70). Platelet inhibitor use was associated with a decreased patient-reported history of malignancy in a multivariate logistic regression adjusted for age, sex, body mass index, comorbidity, and number of medications (OR = 0.66; CI 0.44-0.99; <it>P </it>= .045). Similar odds of association were seen in both males and females, and for aspirin and non-aspirin platelet inhibitor therapy.</p> <p>Conclusions</p> <p>Our data suggest an association between anti-platelet drug use and reduced cancer prevalence in patients with diabetes. Given the potentially large implications of our observations in the diabetic population, further studies are required to determine if this association is causal.</p