Information heat engine: converting information to energy by feedback control

In 1929, Leo Szilard invented a feedback protocol in which a hypothetical intelligence called Maxwell's demon pumps heat from an isothermal environment and transduces it to work. After an intense controversy that lasted over eighty years; it was finally clarified that the demon's role does not contradict the second law of thermodynamics, implying that we can convert information to free energy in principle. Nevertheless, experimental demonstration of this information-to-energy conversion has been elusive. Here, we demonstrate that a nonequilibrium feedback manipulation of a Brownian particle based on information about its location achieves a Szilard-type information-energy conversion. Under real-time feedback control, the particle climbs up a spiral-stairs-like potential exerted by an electric field and obtains free energy larger than the amount of work performed on it. This enables us to verify the generalized Jarzynski equality, or a new fundamental principle of "information-heat engine" which converts information to energy by feedback control.Comment: manuscript including 7 pages and 4 figures and supplementary material including 6 pages and 8 figure

Evidence on anti-malarial and diagnostic markets in Cambodia to guide malaria elimination strategies and policies

BACKGROUND: Understanding Cambodia's anti-malarial and diagnostic landscape in 2015 is critical for informing and monitoring strategies and policies as Cambodia moves forward with national efforts to eliminate malaria. The aim of this paper is to present timely and key findings on the public and private sector anti-malarial and diagnostic landscape in Cambodia. This evidence can serve as a baseline benchmark for guiding implementation of national strategies as well as other regional initiatives to address malaria elimination activities. METHODS: From August 17th to October 1st, 2015, a cross sectional, nationally-representative malaria outlet survey was conducted in Cambodia. A census of all public and private outlets with potential to distribute malaria testing and/or treatment was conducted among 180 communes. An audit was completed for all anti-malarials, malaria rapid diagnostic tests (RDT) and microscopy. RESULTS: A total of 26,664 outlets were screened, and 1303 outlets were eligible and interviewed. Among all screened outlets in the public sector, 75.9% of public health facilities and 67.7% of community health workers stocked both malaria diagnostic testing and a first-line artemisinin-based combination therapy (ACT). Among anti-malarial-stocking private sector outlets, 64.7% had malaria blood testing available, and 70.9% were stocking a first-line ACT. Market share data illustrate that most of the anti-malarials were sold or distributed through the private sector (58.4%), including itinerant drug vendors (23.4%). First-line ACT accounted for the majority of the market share across the public and private sectors (90.3%). Among private sector outlets stocking any anti-malarial, the proportion of outlets with a first-line ACT or RDT was higher among outlets that had reportedly received one or more forms of 'support' (e.g. reportedly received training in the previous year on malaria diagnosis [RDT and/or microscopy] and/or the national treatment guidelines for malaria) compared to outlets that did not report receiving any support (ACT: 82.1 and 60.6%, respectively; RDT: 78.2 and 64.0%, respectively). CONCLUSION: The results point to high availability and distribution of first-line ACT and widespread availability of malaria diagnosis, especially in the public sector. This suggests that there is a strong foundation for achieving elimination goals in Cambodia. However, key gaps in terms of availability of malaria commodities for case management must be addressed, particularly in the private sector where most people seek treatment. Continued engagement with the private sector will be important to ensure accelerated progress towards malaria elimination

Study protocol of cost-effectiveness and cost-utility of a biopsychosocial multidisciplinary intervention in the evolution of non-specific sub-acute low back pain in the working population: cluster randomised trial.

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Low back pain (LBP), with high incidence and prevalence rate, is one of the most common reasons to consult the health system and is responsible for a significant amount of sick leave, leading to high health and social costs. The objective of the study is to assess the cost-effectiveness and cost-utility analysis of a multidisciplinary biopsychosocial educational group intervention (MBEGI) of non-specific sub-acute LBP in comparison with the usual care in the working population recruited in primary healthcare centres. Methods/design: The study design is a cost-effectiveness and cost-utility analysis of a MBEGI in comparison with the usual care of non-specific sub-acute LBP.Measures on effectiveness and costs of both interventions will be obtained from a cluster randomised controlled clinical trial carried out in 38 Catalan primary health care centres, enrolling 932 patients between 18 and 65 years old with a diagnosis of non-specific sub-acute LBP. Effectiveness measures are: pharmaceutical treatments, work sick leave (% and duration in days), Roland Morris disability, McGill pain intensity, Fear Avoidance Beliefs (FAB) and Golberg Questionnaires. Utility measures will be calculated from the SF-12. The analysis will be performed from a social perspective. The temporal horizon is at 3 months (change to chronic LBP) and 12 months (evaluate the outcomes at long term. Assessment of outcomes will be blinded and will follow the intention-to-treat principle. Discussion: We hope to demonstrate the cost-effectiveness and cost-utility of MBEGI, see an improvement in the patients' quality of life, achieve a reduction in the duration of episodes and the chronicity of non-specific low back pain, and be able to report a decrease in the social costs. If the intervention is cost-effectiveness and cost-utility, it could be applied to Primary Health Care Centres. Trial registration: ISRCTN: ISRCTN5871969

Intense violet–blue emission and paramagnetism of nanocrystalline Gd3+ doped ZnO ceramics

Nanocrystalline Zn1-xGdxO (x = 0, 0.02, 0.04, 0.06, and 0.08) ceramics were synthesized by ball milling and subsequent solid-state reaction. The transmission electron microscopy (TEM) micrograph of as synthesized samples revealed the formation of crystallites with an average diameter of 60 nm, and the selected area electron diffraction (SAED) pattern confirmed the formation of wurtzite structure. A red shift in the band gap was observed with increasing Gd3+ concentration. The photoluminescence of nanocrystalline Gd3+ doped ZnO exhibited a strong violet–blue emission. Concentration dependence of the emission intensity of Gd3+ in ZnO was studied, and the critical concentration was found to be 4 mol% of Gd3+. The Gd3+ doped ZnO exhibited paramagnetic behavior at room temperature, and the magnetic moment increased with Gd3+ concentration

A Controlled Investigation of Optimal Internal Medicine Ward Team Structure at a Teaching Hospital

BACKGROUND: The optimal structure of an internal medicine ward team at a teaching hospital is unknown. We hypothesized that increasing the ratio of attendings to housestaff would result in an enhanced perceived educational experience for residents. METHODS: Harbor-UCLA Medical Center (HUMC) is a tertiary care, public hospital in Los Angeles County. Standard ward teams at HUMC, with a housestaff∶attending ratio of 5:1, were split by adding one attending and then dividing the teams into two experimental teams containing ratios of 3:1 and 2:1. Web-based Likert satisfaction surveys were completed by housestaff and attending physicians on the experimental and control teams at the end of their rotations, and objective healthcare outcomes (e.g., length of stay, hospital readmission, mortality) were compared. RESULTS: Nine hundred and ninety patients were admitted to the standard control teams and 184 were admitted to the experimental teams (81 to the one-intern team and 103 to the two-intern team). Patients admitted to the experimental and control teams had similar age and disease severity. Residents and attending physicians consistently indicated that the quality of the educational experience, time spent teaching, time devoted to patient care, and quality of life were superior on the experimental teams. Objective healthcare outcomes did not differ between experimental and control teams. CONCLUSIONS: Altering internal medicine ward team structure to reduce the ratio of housestaff to attending physicians improved the perceived educational experience without altering objective healthcare outcomes