Systematic and Controllable Negative, Zero, and Positive Thermal Expansion in Cubic Zr1–xSnxMo2O8

We describe the synthesis and characterization of a family of materials, Zr1–xSnxMo2O8 (0 < x < 1), whose isotropic thermal expansion coefficient can be systematically varied from negative to zero to positive values. These materials allow tunable expansion in a single phase as opposed to using a composite system. Linear thermal expansion coefficients, αl, ranging from −7.9(2) × 10–6 to +5.9(2) × 10–6 K–1 (12–500 K) can be achieved across the series; contraction and expansion limits are of the same order of magnitude as the expansion of typical ceramics. We also report the various structures and thermal expansion of “cubic” SnMo2O8, and we use time- and temperature-dependent diffraction studies to describe a series of phase transitions between different ordered and disordered states of this material

Mitochondrial dysfunction and biogenesis: do ICU patients die from mitochondrial failure?

Mitochondrial functions include production of energy, activation of programmed cell death, and a number of cell specific tasks, e.g., cell signaling, control of Ca2+ metabolism, and synthesis of a number of important biomolecules. As proper mitochondrial function is critical for normal performance and survival of cells, mitochondrial dysfunction often leads to pathological conditions resulting in various human diseases. Recently mitochondrial dysfunction has been linked to multiple organ failure (MOF) often leading to the death of critical care patients. However, there are two main reasons why this insight did not generate an adequate resonance in clinical settings. First, most data regarding mitochondrial dysfunction in organs susceptible to failure in critical care diseases (liver, kidney, heart, lung, intestine, brain) were collected using animal models. Second, there is no clear therapeutic strategy how acquired mitochondrial dysfunction can be improved. Only the benefit of such therapies will confirm the critical role of mitochondrial dysfunction in clinical settings. Here we summarized data on mitochondrial dysfunction obtained in diverse experimental systems, which are related to conditions seen in intensive care unit (ICU) patients. Particular attention is given to mechanisms that cause cell death and organ dysfunction and to prospective therapeutic strategies, directed to recover mitochondrial function. Collectively the data discussed in this review suggest that appropriate diagnosis and specific treatment of mitochondrial dysfunction in ICU patients may significantly improve the clinical outcome

Provider and Practice Characteristics Associated with Use of Rapid HIV Testing by General Internists

Background. Rapid HIV testing could increase routine HIV testing. Most previous studies of rapid testing were conducted in acute care settings, and few described the primary care providers’ perspective. Objective – To identify characteristics of general internal medicine physicians with access to rapid HIV testing, and to determine whether such access is associated with differences in HIV-testing practices or perceived HIV-testing barriers. Design – Web-based cross-sectional survey conducted in 2009. Participants - 406 physician members of the Society of General Internal Medicine who supervise residents or provide care in outpatient settings. Main measures. Surveys assessed provider and practice characteristics, HIV-testing types, HIV-testing behavior, and potential barriers to HIV testing. Results. Among respondents, 15% had access to rapid HIV testing. In multivariable analysis, physicians were more likely to report access to rapid testing if they were non-white (OR 0.45, 95% CI 0.22, 0.91), had more years since completing training (OR 1.06, 95% CI 1.02, 1.10), practiced in the Northeastern US (OR 2.35; 95% CI 1.28, 4.32), or if their practice included a higher percentage of uninsured patients (OR 1.03; 95% CI 1.01, 1.04). Internists with access to rapid testing reported fewer barriers to HIV testing. More respondents with rapid than standard testing reported at least 25% of their patients received HIV testing (51% versus 35%, p =.02). However, access to rapid HIV testing was not significantly associated with the estimated proportion of patients receiving HIV testing within the previous 30 days (7.24% vs. 4.58%, p=.06). Conclusion. Relatively few internists have access to rapid HIV testing in outpatient settings, with greater availability of rapid testing in community-based clinics and in the Northeastern U.S. Future research may determine whether access to rapid testing in primary care settings will impact routinizing HIV testing