Physics in Riemann's mathematical papers

Riemann's mathematical papers contain many ideas that arise from physics, and some of them are motivated by problems from physics. In fact, it is not easy to separate Riemann's ideas in mathematics from those in physics. Furthermore, Riemann's philosophical ideas are often in the background of his work on science. The aim of this chapter is to give an overview of Riemann's mathematical results based on physical reasoning or motivated by physics. We also elaborate on the relation with philosophy. While we discuss some of Riemann's philosophical points of view, we review some ideas on the same subjects emitted by Riemann's predecessors, and in particular Greek philosophers, mainly the pre-socratics and Aristotle. The final version of this paper will appear in the book: From Riemann to differential geometry and relativity (L. Ji, A. Papadopoulos and S. Yamada, ed.) Berlin: Springer, 2017

An innovative telemedicine knowledge translation program to improve quality of care in intensive care units: protocol for a cluster randomized pragmatic trial

Abstract Background There are challenges to timely adoption of, and ongoing adherence to, evidence-based practices known to improve patient care in the intensive care unit (ICU). Quality improvement initiatives using a collaborative network approach may increase the use of such practices. Our objective is to evaluate the effectiveness of a novel knowledge translation program for increasing the proportion of patients who appropriately receive the following six evidence-based care practices: venous thromboembolism prophylaxis; ventilator-associated pneumonia prevention; spontaneous breathing trials; catheter-related bloodstream infection prevention; decubitus ulcer prevention; and early enteral nutrition. Methods and design We will conduct a pragmatic cluster randomized active control trial in 15 community ICUs and one academic ICU in Ontario, Canada. The intervention is a multifaceted videoconferenced educational and problem-solving forum to organize knowledge translation strategies, including comparative audit and feedback, educational sessions from content experts, and dissemination of algorithms. Fifteen individual ICUs (clusters) will be randomized to receive quality improvement interventions targeting one of the best practices during each of six study phases. Each phase lasts four months during the first study year and three months during the second. At the end of each study phase, ICUs are assigned to an intervention for a best practice not yet received according to a random schedule. The primary analysis will use patient-level process-of-care data to measure the intervention's effect on rates of adoption and adherence of each best practice in the targeted ICU clusters versus controls. Discussion This study design evaluates a new system for knowledge translation and quality improvement across six common ICU problems. All participating ICUs receive quality improvement initiatives during every study phase, improving buy-in. This study design could be considered for other quality improvement interventions and in other care settings. Trial Registration This trial is registered with http://www.clinicaltrials.gov (ID #: NCT00332982

Survey of information technology in Intensive Care Units in Ontario, Canada

<p>Abstract</p> <p>Background</p> <p>The Intensive Care Unit (ICU) is a data-rich environment where information technology (IT) may enhance patient care. We surveyed ICUs in the province of Ontario, Canada, to determine the availability, implementation and variability of information systems.</p> <p>Methods</p> <p>A self-administered internet-based survey was completed by ICU directors between May and October 2006. We measured the spectrum of ICU clinical data accessible electronically, the availability of decision support tools, the availability of electronic imaging systems for radiology, the use of electronic order entry and medication administration systems, and the availability of hardware and wireless or mobile systems. We used Fisher's Exact tests to compare IT availability and Classification and Regression Trees (CART) to estimate the optimal cut-point for the number of computers per ICU bed.</p> <p>Results</p> <p>We obtained responses from 50 hospitals (68.5% of institutions with level 3 ICUs), of which 21 (42%) were university-affiliated. The majority electronically accessed laboratory data and imaging reports (92%) and used picture archiving and communication systems (PACS) (76%). Other computing functions were less prevalent (medication administration records 46%, physician or nursing notes 26%; medication order entry 22%). No association was noted between IT availability and ICU size or university affiliation. Sites used clinical information systems from15 different vendors and 8 different PACS systems were in use. Half of the respondents described the number of computers available as insufficient. Wireless networks and mobile computing systems were used in 23 ICUs (46%).</p> <p>Conclusion</p> <p>Ontario ICUs demontrate a high prevalence of the use of basic information technology systems. However, implementation of the more complex and potentially more beneficial applications is low. The wide variation in vendors utilized may impair information exchange, interoperability and uniform data collection.</p

Dietary calcium and vitamin D intakes in childhood and throughout adulthood and mammographic density in a British birth cohort

We examined the role of dietary calcium and vitamin D intakes in childhood and throughout adulthood in relation to mammographic density using data from a nationally representative cohort of 1161 women followed up since their birth in 1946. Dietary intakes at the age of 4 years were determined by 24-h recalls and at the ages of 36, 43 and 53 years by 5-day food records. After adjusting for known risk factors and confounders, no evidence of a relationship between dietary calcium or vitamin D intakes and mammographic density approximately at the age of 50 years was found, except for a cross-sectional relationship between dietary calcium intake at the age of 53 years and breast density in women who were post-menopausal at the time of mammography, with those in the top fifth of the distribution of calcium intake having a 0.53 s.d. lower percent breast density than those in the lowest fifth (P-value <0.01 for linear trend)

Soil and Cultivar Type Shape the Bacterial Community in the Potato Rhizosphere

The rhizospheres of five different potato cultivars (including a genetically modified cultivar) obtained from a loamy sand soil and two from a sandy peat soil, next to corresponding bulk soils, were studied with respect to their community structures and potential function. For the former analyses, we performed bacterial 16S ribosomal RNA gene-based PCR denaturing gradient gel electrophoresis (PCR-DGGE) on the basis of soil DNA; for the latter, we extracted microbial communities and subjected these to analyses in phenotype arrays (PM1, PM2, and PM4, Biolog), with a focus on the use of different carbon, sulfur and phosphorus sources. In addition, we performed bacterial PCR-DGGE on selected wells to assess the structures of these substrate-responsive communities. Effects of soil type, the rhizosphere, and cultivar on the microbial community structures were clearly observed. Soil type was the most determinative parameter shaping the functional communities, whereas the rhizosphere and cultivar type also exerted an influence. However, no genetically modified plant effect was observed. The effects were imminent based on general community analysis and also single-compound analysis. Utilization of some of the carbon and sulfur sources was specific per cultivar, and different microbial communities were found as defined by cultivar. Thus, both soil and cultivar type shaped the potato root-associated bacterial communities that were responsive to some of the substrates in phenotype arrays

Reasons for non-vaccination against HPV and future vaccination intentions among 19-26 year-old women

<p>Abstract</p> <p>Background</p> <p>Despite CDC recommendations regarding universal catch-up vaccination against human papillomavirus (HPV), only about ten percent of young adult women in the United States have been vaccinated. The purpose of this study was to better understand reasons for non-vaccination among insured 19-26 year-old women and to evaluate future vaccination intentions.</p> <p>Methods</p> <p>We used an administrative claims database from a large US managed care plan to identify women aged 19-26 for receipt of a mailed survey. From a sample of 1,375 women with no evidence of HPV vaccination from June 1, 2006 through April 30, 2007, 222 completed surveys were received, of which 185 were eligible for this analysis. The main outcome measures were unvaccinated women's attitudes and vaccine awareness, likelihood of future action regarding the vaccine, and reasons for inaction.</p> <p>Results</p> <p>Among the 185 non-vaccinees, 25.4% were married, 83.2% were white, and 89.2% had a college or higher level education. The vaccine was described as very important by 32.4% of subjects, and 30.1% had discussed the vaccine with a doctor and received a doctor's recommendation. Half or fewer of respondents were "very" or "extremely" likely to discuss the vaccine with their doctor (50.0%), do additional research on the vaccine (42.6%), ask a doctor to get the vaccine (37.5%), or make an appointment to get the vaccine (27.8%), while 48.0% were "somewhat", "very", or "extremely" likely to do nothing to get the vaccine. Among the latter, reasons for taking no action included being married or in a monogamous relationship (54.9%), belief that the vaccine is too new (35.4%), not having enough information about the vaccine (31.7%), concerns about side effects (24.4%), and uncertainty about insurance coverage (24.4%).</p> <p>Conclusions</p> <p>Educational interventions may be needed to enhance HPV vaccination rates among 19-26 year-old women, particularly regarding information about vaccine safety, vaccine efficacy, insurance coverage, and the value of vaccination to women in monogamous relationships.</p

Gene Expression Profiling in the Type 1 Diabetes Rat Diaphragm

BACKGROUND:Respiratory muscle contractile performance is impaired by diabetes, mechanisms of which included altered carbohydrate and lipid metabolism, oxidative stress and changes in membrane electrophysiology. The present study examined to what extent these cellular perturbations involve changes in gene expression. METHODOLOGY/PRINCIPAL FINDINGS:Diaphragm muscle from streptozotocin-diabetic rats was analyzed with Affymetrix gene expression arrays. Diaphragm from diabetic rats had 105 genes with at least +/-2-fold significantly changed expression (55 increased, 50 decreased), and these were assigned to gene ontology groups based on over-representation analysis using DAVID software. There was increased expression of genes involved in palmitoyl-CoA hydrolase activity (a component of lipid metabolism) (P = 0.037, n = 2 genes, fold change 4.2 to 27.5) and reduced expression of genes related to carbohydrate metabolism (P = 0.000061, n = 8 genes, fold change -2.0 to -8.5). Other gene ontology groups among upregulated genes were protein ubiquitination (P = 0.0053, n = 4, fold change 2.2 to 3.4), oxidoreductase activity (P = 0.024, n = 8, fold change 2.1 to 6.0), and morphogenesis (P = 0.012, n = 10, fold change 2.1 to 4.3). Other downregulated gene groups were extracellular region (including extracellular matrix and collagen) (P = 0.00032, n = 13, fold change -2.2 to -3.7) and organogenesis (P = 0.032, n = 7, fold change -2.1 to -3.7). Real-time PCR confirmed the directionality of changes in gene expression for 30 of 31 genes tested. CONCLUSIONS/SIGNIFICANCE:These data indicate that in diaphragm muscle type 1 diabetes increases expression of genes involved in lipid energetics, oxidative stress and protein ubiquitination, decreases expression of genes involved in carbohydrate metabolism, and has little effect on expression of ion channel genes. Reciprocal changes in expression of genes involved in carbohydrate and lipid metabolism may change the availability of energetic substrates and thereby directly modulate fatigue resistance, an important issue for a muscle like the diaphragm which needs to contract without rest for the entire lifetime of the organism

Female asylum seekers with musculoskeletal pain: the importance of diagnosis and treatment of hypovitaminosis D

BACKGROUND: Hypovitaminosis D is well known in different populations, but may be under diagnosed in certain populations. We aim to determine the first diagnosis considered, the duration and resolution of symptoms, and the predictors of response to treatment in female asylum seekers suffering from hypovitaminosis D. METHODS: Design: A pre- and post-intervention observational study. Setting: A network comprising an academic primary care centre and nurse practitioners. Participants: Consecutive records of 33 female asylum seekers with complaints compatible with osteomalacia and with hypovitaminosis D (serum 25-(OH) vitamin D <21 nmol/l). Treatment intervention: The patients received either two doses of 300,000 IU intramuscular cholecalciferol as well as 800 IU of cholecalciferol with 1000 mg of calcium orally, or the oral treatment only. Main outcome measures: We recorded the first diagnosis made by the physicians before the correct diagnosis of hypovitaminosis D, the duration of symptoms before diagnosis, the responders and non-responders to treatment, the duration of symptoms after treatment, and the number of medical visits and analgesic drugs prescribed 6 months before and 6 months after diagnosis. Tests: Two-sample t-tests, chi-squared tests, and logistic regression analyses were performed. Analyses were performed using SPSS 10.0. RESULTS: Prior to the discovery of hypovitaminosis D, diagnoses related to somatisation were evoked in 30 patients (90.9%). The mean duration of symptoms before diagnosis was 2.53 years (SD 3.20). Twenty-two patients (66.7%) responded completely to treatment; the remaining patients were considered to be non-responders. After treatment was initiated, the responders' symptoms disappeared completely after 2.84 months. The mean number of emergency medical visits fell from 0.88 (SD 1.08) six months before diagnosis to 0.39 (SD 0.83) after (P = 0.027). The mean number of analgesic drugs that were prescribed also decreased from 1.67 (SD 1.5) to 0.85 (SD 1) (P = 0.001). CONCLUSION: Hypovitaminosis D in female asylum seekers may remain undiagnosed, with a prolonged duration of chronic symptoms. The potential pitfall is a diagnosis of somatisation. Treatment leads to a rapid resolution of symptoms, a reduction in the use of medical services, and the prescription of analgesic drugs in this vulnerable population

Selective Breeding for a Behavioral Trait Changes Digit Ratio

The ratio of the length of the second digit (index finger) divided by the fourth digit (ring finger) tends to be lower in men than in women. This 2D∶4D digit ratio is often used as a proxy for prenatal androgen exposure in studies of human health and behavior. For example, 2D∶4D ratio is lower (i.e. more “masculinized”) in both men and women of greater physical fitness and/or sporting ability. Lab mice have also shown variation in 2D∶4D as a function of uterine environment, and mouse digit ratios seem also to correlate with behavioral traits, including daily activity levels. Selective breeding for increased rates of voluntary exercise (wheel running) in four lines of mice has caused correlated increases in aerobic exercise capacity, circulating corticosterone level, and predatory aggression. Here, we show that this selection regime has also increased 2D∶4D. This apparent “feminization” in mice is opposite to the relationship seen between 2D∶4D and physical fitness in human beings. The present results are difficult to reconcile with the notion that 2D∶4D is an effective proxy for prenatal androgen exposure; instead, it may more accurately reflect effects of glucocorticoids, or other factors that regulate any of many genes