Nonlinear structural response using adaptive dynamic relaxation on a massively-parallel-processing system

A parallel adaptive dynamic relaxation (ADR) algorithm has been developed for nonlinear structural analysis. This algorithm has minimal memory requirements, is easily parallelizable and scalable to many processors, and is generally very reliable and efficient for highly nonlinear problems. Performance evaluations on single-processor computers have shown that the ADR algorithm is reliable and highly vectorizable, and that it is competitive with direct solution methods for the highly nonlinear problems considered. The present algorithm is implemented on the 512-processor Intel Touchstone DELTA system at Caltech, and it is designed to minimize the extent and frequency of interprocessor communication. The algorithm has been used to solve for the nonlinear static response of two and three dimensional hyperelastic systems involving contact. Impressive relative speedups have been achieved and demonstrate the high scalability of the ADR algorithm. For the class of problems addressed, the ADR algorithm represents a very promising approach for parallel-vector processing

Stimulation of the gerbil's gustatory receptors by polyols

The gustatory responses of the Mongolian gerbil were tested with 12 sugar alcohols. The electrophysiological effectiveness of the linear polyols as gustatory stimulants increased as the length of the carbon chain increased from 2 to 5. Six and 7 carbon acyclic polyols were no more effective than the pentitols. By comparison myoinositol, a cyclic polyol, was more effective in evoking a response. Responses to mixtures of -sorbitol and sucrose suggest that these sugars compete for a common receptor site. A sucrose receptor site and a model of it is proposed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21723/1/0000115.pd

OMAE2006-92674 ANALYSIS OF TURBULENT FLOWS AND VIV OF TRUSS SPAR RISERS

ABSTRACT Complex flows through riser arrays, such as the case of risers located in the truss section of a truss spar, are very difficult to describe and analyze. It is especially difficult predict and correct Vortex Induced Vibration (VIV) response using traditional tools that were meant to analyze single risers rather than arrays of risers. Computational Fluid Dynamics (CFD) offers the designer the capability to properly analyze these complex problems, increasing the reliability of the design. In this study, a full scale truss spar with vertical risers is modeled using CFD. The VIV response of the risers is predicted and the effect of risers is correctly captured and compared with experiments

Structure and function of a spectrin-like regulator of bacterial cytokinesis

© 2014 Macmillan Publishers Limited. All rights reserved. Bacterial cell division is facilitated by a molecular machine - the divisome - that assembles at mid-cell in dividing cells. The formation of the cytokinetic Z-ring by the tubulin homologue FtsZ is regulated by several factors, including the divisome component EzrA. Here we describe the structure of the 60-kDa cytoplasmic domain of EzrA, which comprises five linear repeats of an unusual triple helical bundle. The EzrA structure is bent into a semicircle, providing the protein with the potential to interact at both N- and C-termini with adjacent membrane-bound divisome components. We also identify at least two binding sites for FtsZ on EzrA and map regions of EzrA that are responsible for regulating FtsZ assembly. The individual repeats, and their linear organization, are homologous to the spectrin proteins that connect actin filaments to the membrane in eukaryotes, and we thus propose that EzrA is the founding member of the bacterial spectrin family

Access to healthy foods: Part I. Barriers to accessing healthy foods: Differentials by gender, social class, income and mode of transport

This paper examines the issues of access to food and the influences people face when shopping for a healthy food basket. It uses data from the Health Edu cation Authority's 1993 Health and Lifestyles Survey to examine the barriers people face in accessing a healthy diet. The main findings are that access to food is primarily determined by income, and this is in turn closely related to physical resources available to access healthy food. There is an associated class bias over access to sources of healthy food. The poor have less access to a car, find it harder to get to out-of-town shopping centres and thus are less able to carry and transport food in bulk. The majority of people shop in supermarkets as they report that local shops do not provide the services people demand and that food choice and quality are limited. In tackling food poverty and pro moting healthy eating, health promotion practice needs to address these struc tural issues as opposed to relying on psycho-social models of education based on the provision of information and choice

International Public Health Research Involving Interpreters: a Case Study from Bangladesh

Background: Cross-cultural and international research are important components of public health research, but the challenges of language barriers and working with interpreters are often overlooked, particularly in the case of qualitative research. Methods: A case-study approach was used to explore experiences of working with an interpreter in Bangladesh as part of a research project investigating women's experiences of emergency obstetric care. The case study: Data from the researcher's field notes provided evidence of experiences in working with an interpreter and show how the model of interviewing was adapted over time to give a more active role to the interpreter. The advantages of a more active role were increased rapport and "flow" in interviews. The disadvantages included reduced control from the researcher's perspective. Some tensions between the researcher and interpreter remained hard to overcome, irrespective of the model used. Independent transcription and translation of the interviews also raised questions around accuracy in translation. Conclusion: The issues examined in this case study have broader implications for public health research. Further work is needed in three areas: 1) developing effective relationships with interpreters; 2) the impact of the interpreter on the research process; and 3) the accuracy of the translation and level of analysis needed in any specific public health research. Finally, this paper highlights the importance to authors of reflecting on the potential impact of translation and interpretation on the research process when disseminating their research

Ovine pedomics : the first study of the ovine foot 16S rRNA-based microbiome

We report the first study of the bacterial microbiome of ovine interdigital skin based on 16S rRNA by pyrosequencing and conventional cloning with Sanger-sequencing. Three flocks were selected, one a flock with no signs of footrot or interdigital dermatitis, a second flock with interdigital dermatitis alone and a third flock with both interdigital dermatitis and footrot. The sheep were classified as having either healthy interdigital skin (H), interdigital dermatitis (ID) or virulent footrot (VFR). The ovine interdigital skin bacterial community varied significantly by flock and clinical condition. The diversity and richness of operational taxonomic units was greater in tissue from sheep with ID than H or VFR affected sheep. Actinobacteria, Bacteriodetes, Firmicutes and Proteobacteria were the most abundant phyla comprising 25 genera. Peptostreptococcus, Corynebacterium and Staphylococcus were associated with H, ID and VFR respectively. Sequences of Dichelobacter nodosus, the causal agent of ovine footrot, were not amplified due to mismatches in the 16S rRNA universal forward primer (27F). A specific real time PCR assay was used to demonstrate the presence of D. nodosus which was detected in all samples including the flock with no signs of ID or VFR. Sheep with ID had significantly higher numbers of D. nodosus (104-109 cells/g tissue) than those with H or VFR feet

How Mistimed and Unwanted Pregnancies Affect Timing of Antenatal Care Initiation in three Districts in Tanzania

Early antenatal care (ANC) initiation is a doorway to early detection and management of potential complications associated with pregnancy. Although the literature reports various factors associated with ANC initiation such as parity and age, pregnancy intentions is yet to be recognized as a possible predictor of timing of ANC initiation. Data originate from a cross-sectional household survey on health behaviour and service utilization patterns. The survey was conducted in 2011 in Rufiji, Kilombero and Ulanga districts in Tanzania on 910 women of reproductive age who had given birth in the past two years. ANC initiation was considered to be early only if it occurred in the first trimester of pregnancy gestation. A recently completed pregnancy was defined as mistimed if a woman wanted it later, and if she did not want it at all the pregnancy was termed as unwanted. Chisquare was used to test for associations and multinomial logistic regression was conducted to examine how mistimed and unwanted pregnancies affect timing of ANC initiation. Although 49.3% of the women intended to become pregnant, 50.7% (34.9% mistimed and 15.8% unwanted) became pregnant unintentionally. While ANC initiation in the 1st trimester was 18.5%, so was 71.7% and 9.9% in the 2nd and 3rd trimesters respectively. Multivariate analysis revealed that ANC initiation in the 2nd trimester was 1.68 (95% CI 1.10‒2.58) and 2.00 (95% CI 1.05‒3.82) times more likely for mistimed and unwanted pregnancies respectively compared to intended pregnancies. These estimates rose to 2.81 (95% CI 1.41‒5.59) and 4.10 (95% CI 1.68‒10.00) respectively in the 3rd trimester. We controlled for gravidity, age, education, household wealth, marital status, religion, district of residence and travel time to a health facility. Late ANC initiation is a significant maternal and child health consequence of mistimed and unwanted pregnancies in Tanzania. Women should be empowered to delay or avoid pregnancies whenever they need to do so. Appropriate counseling to women, especially those who happen to conceive unintentionally is needed to minimize the possibility of delaying ANC initiation.\u