CrO2: a self-doped double exchange ferromagnet

Band structure calculations of CrO2 carried out in the LSDA+U approach reveal a clear picture of the physics behind the metallic ferromagnetic properties. Arguments are presented that the metallic ferromagnetic oxide CrO2 belongs to a class of materials in which magnetic ordering exists due to double exchange (in this respect CrO2 turns out to be similar to the CMR manganates). It is concluded that CrO2 has small or even negative charge transfer gap which can result in self-doping. Certain experiments to check the proposed picture are suggested.Comment: 4 pages, 4 Figure

Glycemia Determines the Effect of Type 2 Diabetes Risk Genes on Insulin Secretion

OBJECTIVE—Several single nucleotide polymorphisms (SNPs) in diabetes risk genes reduce glucose- and/or incretin-induced insulin secretion. Here, we investigated interactions between glycemia and such diabetes risk polymorphisms. RESEARCH DESIGN AND METHODS—Insulin secretion was assessed by insulinogenic index and areas under the curve of C-peptide/glucose in 1,576 subjects using an oral glucose toler-ance test (OGTT). Participants were genotyped for 10 diabetes risk SNPs associated with -cell dysfunction: rs5215 (KCNJ11), rs13266634 (SLC30A8), rs7754840 (CDKAL1), rs10811661 (CDKN2A/2B), rs10830963 (MTNR1B), rs7903146 (TCF7L2), rs10010131 (WFS1), rs7923837 (HHEX), rs151290 (KCNQ1), an

Analytic philosophy for biomedical research: the imperative of applying yesterday's timeless messages to today's impasses

The mantra that "the best way to predict the future is to invent it" (attributed to the computer scientist Alan Kay) exemplifies some of the expectations from the technical and innovative sides of biomedical research at present. However, for technical advancements to make real impacts both on patient health and genuine scientific understanding, quite a number of lingering challenges facing the entire spectrum from protein biology all the way to randomized controlled trials should start to be overcome. The proposal in this chapter is that philosophy is essential in this process. By reviewing select examples from the history of science and philosophy, disciplines which were indistinguishable until the mid-nineteenth century, I argue that progress toward the many impasses in biomedicine can be achieved by emphasizing theoretical work (in the true sense of the word 'theory') as a vital foundation for experimental biology. Furthermore, a philosophical biology program that could provide a framework for theoretical investigations is outlined

Perceptions and utilization of primary health care services in Iraq: findings from a national household survey

<p>Abstract</p> <p>Background</p> <p>After many years of sanctions and conflict, Iraq is rebuilding its health system, with a strong emphasis on the traditional hospital-based services. A network exists of public sector hospitals and clinics, as well as private clinics and a few private hospitals. Little data are available about the approximately 1400 Primary Health Care clinics (PHCCs) staffed with doctors. How do Iraqis utilize primary health care services? What are their preferences and perceptions of public primary health care clinics and private primary care services in general? How does household wealth affect choice of services?</p> <p>Methods</p> <p>A 1256 household national survey was conducted in the catchment areas of randomly selected PHCCs in Iraq. A cluster of 10 households, beginning with a randomly selected start household, were interviewed in the service areas of seven public sector PHCC facilities in each of 17 of Iraq's 18 governorates. A questionnaire was developed using key informants. Teams of interviewers, including both males and females, were recruited and provided a week of training which included field practice. Teams then gathered data from households in the service areas of randomly selected clinics.</p> <p>Results</p> <p>Iraqi participants are generally satisfied with the quality of primary care services available both in the public and private sector. Private clinics are generally the most popular source of primary care, however the PHCCs are utilized more by poorer households. In spite of free services available at PHCCs many households expressed difficulty in affording health care, especially in the purchase of medications. There is no evidence of informal payments to secure health services in the public sector.</p> <p>Conclusions</p> <p>There is widespread satisfaction reported with primary health care services, and levels did not differ appreciably between public and private sectors. The public sector PHCCs are preferentially used by poorer populations where they are important providers. PHCC services are indeed free, with little evidence of informal payments to providers.</p

Effects of storage conditions of Moringa oleifera seeds on its performance in coagulation

Moringa oleifera is a plant whose seeds have coagulation properties for treating water and wastewater. In this study the coagulation efficiency of Moringa oleifera kept in different storage conditions were studied. The Moringa oleifera seeds were stored at different conditions and durations; open container and closed container at room temperature (28 °C) and refrigerator (3 °C) for durations of 1, 3 and 5 months. Comparison between turbidity removal efficiency of Moringa oleifera kept in refrigerator and room temperature revealed that there was no significant difference between them. The Moringa oleifera kept in refrigerator and room temperature for one month showed higher turbidity removal efficiency, compared to those kept for 3 and 5 months, at both containers. The coagulation efficiency of Moringa oleifera was found to be dependent on initial turbidity of water samples. Highest turbidity removals were obtained for water with very high initial turbidity. In summary coagulation efficiency of Moringa oleifera was found independent of storage temperature and container, however coagulation efficiency of Moringa oleifera decreased as storage duration increased. In addition, Moringa oleifera can be used as a potential coagulant especially for very high turbidity water

Effects of storage duration and temperature of Moringa oleifera stock solution on its performance in coagulation

This study presents the effects of storage duration and temperature of Moringa oleifera stock solution on its coagulation efficiency. Moringa oleifera stock solutions, which were kept at room temperature (28°C), were able to remove turbidity from medium, high and very high turbidity water samples and no coagulation activity was observed for low turbidity water and surface water tested. The highest turbidity removals were observed for stock solutions, which were kept for one day. For Moringa oleifera stock solutions, which were stored longer up to 3 days, the turbidity removal efficiencies decreased to 73.6%, 86.8% and 92.3 % for medium, high and very high turbidity water samples respectively. In the case of medium and high turbidity water samples, Moringa oleifera stock solutions, which were kept for more than 3 days did not perform any coagulation process, while for very high turbidity water sample, it was found to coagulate slightly about 14.9 % and 3.9 % for those which were stored for 5 and 7 days, respectively. For those Moringa oleifera stock solutions, which were stored at 3°C up to 5 days, no significant differences were found between their turbidity removal efficiency on medium, high and very high turbidity, while those that were stored for more than 5 day did not perform coagulation. For surface water and low turbidity water samples significant differences were observed between turbidity removal efficiency of Moringa oleifera stored for different durations. Highest turbidity removal for surface water and low turbidity water were obtained using Moringa oleifera which were kept for 3 days or less and it decreased when using Moringa oleifera stock solution, which were stored longer