Einstein\u27s Equations, Lagrangians for General Relativity, and ADM Formalism

Einstein’s equations describe the relation of spacetime curvature and present matter. We will consider the case of a Lorentzian manifold diffeomorphic to ℝ × Σ, where time t ∈ ℝ and the three-dimensional manifold Σ represents space. In a homogeneous and isotropic universe, the three-dimensional manifold Σ of the Lorentzian manifold has Riemann curvature tensor (3)R = KI, where K is a constant and I is the 3 × 3 identity matrix. Space is flat when K = 0, spherical when K is positive, and hyperbolic when K is negative. In this paper, we will show models agreeing with each. We will derive the Schwarzschild metric, find Einstein’s equations from the Lagrangian, and analyze them using Arnowitt-Deser-Misner formalism

Test Characteristics of Urinary Lipoarabinomannan and Predictors of Mortality among Hospitalized HIV-Infected Tuberculosis Suspects in Tanzania.

Tuberculosis is the most common cause of death among patients with HIV infection living in tuberculosis endemic countries, but many cases are not diagnosed pre-mortem. We assessed the test characteristics of urinary lipoarabinomannan (LAM) and predictors of mortality among HIV-associated tuberculosis suspects in Tanzania. We prospectively enrolled hospitalized HIV-infected patients in Dar es Salaam, with ≥2 weeks of cough or fever, or weight loss. Subjects gave 2 mLs of urine to test for LAM using a commercially available ELISA, ≥2 sputum specimens for concentrated AFB smear and solid media culture, and 40 mLs of blood for culture. Among 212 evaluable subjects, 143 (68%) were female; mean age was 36 years; and the median CD4 count 86 cells/mm(3). 69 subjects (33%) had culture confirmation of tuberculosis and 65 (31%) were LAM positive. For 69 cases of sputum or blood culture-confirmed tuberculosis, LAM sensitivity was 65% and specificity 86% compared to 36% and 98% for sputum smear. LAM test characteristics were not different in patients with bacteremia but showed higher sensitivity and lower specificity with decreasing CD4 cell count. Two month mortality was 64 (53%) of 121 with outcomes available. In multivariate analysis there was significant association of mortality with absence of anti-retroviral therapy (p = 0.004) and a trend toward association with a positive urine LAM (p = 0.16). Among culture-negative patients mortality was 9 (75%) of 12 in LAM positive patients and 27 (38%) of 71 in LAM negative patients (p = 0.02). Urine LAM is more sensitive than sputum smear and has utility for the rapid diagnosis of culture-confirmed tuberculosis in this high-risk population. Mortality data raise the possibility that urine LAM may also be a marker for culture-negative tuberculosis

HIV decline in Zimbabwe due to reductions in risky sex? Evidence from a comprehensive epidemiological review

Background Recent data from antenatal clinic (ANC) surveillance and general population surveys suggest substantial declines in human immunodeficiency virus (HIV) prevalence in Zimbabwe. We assessed the contributions of rising mortality, falling HIV incidence and sexual behaviour change to the decline in HIV prevalence. Methods Comprehensive review and secondary analysis of national and local sources on trends in HIV prevalence, HIV incidence, mortality and sexual behaviour covering the period 1985-2007. Results HIV prevalence fell in Zimbabwe over the past decade (national estimates: from 29.3% in 1997 to 15.6% in 2007). National census and survey estimates, vital registration data from Harare and Bulawayo, and prospective local population survey data from eastern Zimbabwe showed substantial rises in mortality during the 1990s levelling off after 2000. Direct estimates of HIV incidence in male factory workers and women attending pre- and post-natal clinics, trends in HIV prevalence in 15-24-year-olds, and back-calculation estimates based on the vital registration data from Harare indicated that HIV incidence may have peaked in the early 1990s and fallen during the 1990s. Household survey data showed reductions in numbers reporting casual partners from the late 1990s and high condom use in non-regular partnerships between 1998 and 2007. Conclusions These findings provide the first convincing evidence of an HIV decline accelerated by changes in sexual behaviour in a southern African country. However, in 2007, one in every seven adults in Zimbabwe was still infected with a life-threatening virus and mortality rates remained at crisis leve

Advancing Alternative Analysis: Integration of Decision Science.

Decision analysis-a systematic approach to solving complex problems-offers tools and frameworks to support decision making that are increasingly being applied to environmental challenges. Alternatives analysis is a method used in regulation and product design to identify, compare, and evaluate the safety and viability of potential substitutes for hazardous chemicals.Assess whether decision science may assist the alternatives analysis decision maker in comparing alternatives across a range of metrics.A workshop was convened that included representatives from government, academia, business, and civil society and included experts in toxicology, decision science, alternatives assessment, engineering, and law and policy. Participants were divided into two groups and prompted with targeted questions. Throughout the workshop, the groups periodically came together in plenary sessions to reflect on other groups' findings.We conclude the further incorporation of decision science into alternatives analysis would advance the ability of companies and regulators to select alternatives to harmful ingredients, and would also advance the science of decision analysis.We advance four recommendations: (1) engaging the systematic development and evaluation of decision approaches and tools; (2) using case studies to advance the integration of decision analysis into alternatives analysis; (3) supporting transdisciplinary research; and (4) supporting education and outreach efforts

An action research protocol to strengthen system-wide inter-professional learning and practice

Background. Inter-professional learning (IPL) and inter-professional practice (IPP) are thought to be critical determinants of effective care, improved quality and safety and enhanced provider morale, yet few empirical studies have demonstrated this. Whole-of-system research is even less prevalent. We aim to provide a four year, multi-method, multi-collaborator action research program of IPL and IPP in defined, bounded health and education systems located in the Australian Capital Territory (ACT). The project is funded by the Australian Research Council under its industry Linkage Program. Methods/Design. The program of research will examine in four inter-related, prospective studies, progress with IPL and IPP across tertiary education providers, professional education, regulatory and registration bodies, the ACT health system's streams of care activities and teams, units and wards of the provider facilities of the ACT health system. One key focus will be on push-pull mechanisms, ie, how the education sector creates student-enabled IPP and the health sector demands IPL-oriented practitioners. The studies will examine four research aims and meet 20 research project objectives in a comprehensive evaluation of ongoing progress with IPL and IPP. Discussion. IPP and IPL are said to be cornerstones of health system reforms. We will measure progress across an entire health system and the clinical and professional education systems that feed into it. The value of multi-methods, partnership research and a bi-directional push-pull model of IPL and IPP will be tested. Widespread dissemination of results to practitioners, policymakers, managers and researchers will be a key project goal

Increased Oxidative Burden Associated with Traffic Component of Ambient Particulate Matter at Roadside and Urban Background Schools Sites in London

As the incidence of respiratory and allergic symptoms has been reported to be increased in children attending schools in close proximity to busy roads, it was hypothesised that PM from roadside schools would display enhanced oxidative potential (OP). Two consecutive one-week air quality monitoring campaigns were conducted at seven school sampling sites, reflecting roadside and urban background in London. Chemical characteristics of size fractionated particulate matter (PM) samples were related to the capacity to drive biological oxidation reactions in a synthetic respiratory tract lining fluid. Contrary to hypothesised contrasts in particulate OP between school site types, no robust size-fractionated differences in OP were identified due high temporal variability in concentrations of PM components over the one-week sampling campaigns. For OP assessed both by ascorbate (OPAA m−3) and glutathione (OPGSH m−3) depletion, the highest OP per cubic metre of air was in the largest size fraction, PM1.9–10.2. However, when expressed per unit mass of particles OPAA µg−1 showed no significant dependence upon particle size, while OPGSH µg−1 had a tendency to increase with increasing particle size, paralleling increased concentrations of Fe, Ba and Cu. The two OP metrics were not significantly correlated with one another, suggesting that the glutathione and ascorbate depletion assays respond to different components of the particles. Ascorbate depletion per unit mass did not show the same dependence as for GSH and it is possible that other trace metals (Zn, Ni, V) or organic components which are enriched in the finer particle fractions, or the greater surface area of smaller particles, counter-balance the redox activity of Fe, Ba and Cu in the coarse particles. Further work with longer-term sampling and a larger suite of analytes is advised in order to better elucidate the determinants of oxidative potential, and to fuller explore the contrasts between site types.\ud \u

Regional Systems of Care Demonstration Project: American Heart Association Mission: Lifeline STEMI Systems Accelerator.

BACKGROUND: Up to 50% of patients fail to meet ST-segment-elevation myocardial infarction (STEMI) guideline goals recommending a first medical contact-to-device time of <90 minutes for patients directly presenting to percutaneous coronary intervention-capable hospitals and <120 minutes for transferred patients. We sought to increase the proportion of patients treated within guideline goals by organizing coordinated regional reperfusion plans. METHODS: We established leadership teams, coordinated protocols, and provided regular feedback for 484 hospitals and 1253 emergency medical services (EMS) agencies in 16 regions across the United States. RESULTS: Between July 2012 and December 2013, 23 809 patients presented with acute STEMI (direct to percutaneous coronary intervention hospital: 11 765 EMS transported and 6502 self-transported; 5542 transferred). EMS-transported patients differed from self-transported patients in symptom onset to first medical contact time (median, 47 versus 114 minutes), incidence of cardiac arrest (10% versus 3%), shock on admission (11% versus 3%), and in-hospital mortality (8% versus 3%; P<0.001 for all comparisons). There was a significant increase in the proportion of patients meeting guideline goals of first medical contact-to-device time, including those directly presenting via EMS (50% to 55%; P<0.001) and transferred patients (44%-48%; P=0.002). Despite regional variability, the greatest gains occurred among patients in the 5 most improved regions, increasing from 45% to 57% (direct EMS; P<0.001) and 38% to 50% (transfers; P<0.001). CONCLUSIONS: This Mission: Lifeline STEMI Systems Accelerator demonstration project represents the largest national effort to organize regional STEMI care. By focusing on first medical contact-to-device time, coordinated treatment protocols, and regional data collection and reporting, we were able to increase significantly the proportion of patients treated within guideline goals