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https://www.readbyqxmd.com/read/28108530/use-of-performance-metrics-for-the-measurement-of-universal-coverage-for-maternal-care-in-mexico
#1
Edson Serván-Mori, David Contreras-Loya, Octavio Gomez-Dantés, Gustavo Nigenda, Sandra G Sosa-Rubí, Rafael Lozano
This study provides evidence for those working in the maternal health metrics and health system performance fields, as well as those interested in achieving universal and effective health care coverage. Based on the perspective of continuity of health care and applying quasi-experimental methods to analyse the cross-sectional 2009 National Demographic Dynamics Survey (n = 14 414 women), we estimated the middle-term effects of Mexico's new public health insurance scheme, Seguro Popular de Salud (SPS) (vs women without health insurance) on seven indicators related to maternal health care (according to official guidelines): (a) access to skilled antenatal care (ANC); (b) timely ANC; (c) frequent ANC; (d) adequate content of ANC; (e) institutional delivery; (f) postnatal consultation and (g) access to standardized comprehensive antenatal and postnatal care (or the intersection of the seven process indicators)...
January 20, 2017: Health Policy and Planning
https://www.readbyqxmd.com/read/28108494/the-rich-club-organization-in-rat-functional-brain-network-to-balance-between-communication-cost-and-efficiency
#2
Xia Liang, Li-Ming Hsu, Hanbing Lu, Akira Sumiyoshi, Yong He, Yihong Yang
Network analyses of structural connectivity in the brain have highlighted a set of highly connected hubs that are densely interconnected, forming a "rich-club" substrate in diverse species. Here, we demonstrate the existence of rich-club organization in functional brain networks of rats. Densely interconnected rich-club regions are found to be distributed in multiple brain modules, with the majority located within the putative default mode network. Rich-club members exhibit high wiring cost (as measured by connection distance) and high metabolic running cost (as surrogated by cerebral blood flow), which may have evolved to achieve high network communications to support efficient brain functions...
January 19, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28108450/netland-quantitative-modeling-and-visualization-of-waddington-s-epigenetic-landscape-using-probabilistic-potential
#3
Jing Guo, Feng Lin, Xiaomeng Zhang, Vivek Tanavde, Jie Zheng
: Waddington's epigenetic landscape is a powerful metaphor for cellular dynamics driven by gene regulatory networks. Its quantitative modeling and visualization, however, remains a challenge, especially when there are more than two genes in the network. A software tool for Waddington's landscape has not been available in the literature. We present NetLand, an open-source software tool for modeling and simulating the kinetic dynamics of gene regulatory networks (GRNs), and visualizing the corresponding Waddington's epigenetic landscape in three dimensions without restriction on the number of genes in a GRN...
January 19, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28108306/bone-remodeling-as-a-spatial-evolutionary-game
#4
Marc D Ryser, Kevin A Murgas
Bone remodeling is a complex process involving cell-cell interactions, biochemical signaling and mechanical stimuli. Early models of the biological aspects of remodeling were non-spatial and focused on the local dynamics at a fixed location in the bone. Several spatial extensions of these models have been proposed, but they generally suffer from two limitations: first, they are not amenable to analysis and are computationally expensive, and second, they neglect the role played by bone-embedded osteocytes. To address these issues, we developed a novel model of spatial remodeling based on the principles of evolutionary game theory...
January 17, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28108173/broach-handle-design-changes-force-distribution-in-the-femur-during-total-hip-arthroplasty
#5
Dustin A Greenhill, Pooyan Abbasi, Kurosh Darvish, Andrew M Star
BACKGROUND: Curved broach handles were developed to overcome limited surgical exposures during total hip arthroplasty. Some authors report increased intraoperative fracture rates during limited exposures. This study evaluates mechanical force ratios transmitted to the bone while broaching with curved vs straight handles. METHODS: An experimental model utilized a 6-axis load cell to measure force distributions produced by 4 different broach handles, each with increasing offset and curvature...
December 29, 2016: Journal of Arthroplasty
https://www.readbyqxmd.com/read/28108004/nonlinear-svm-dtc-for-induction-motor-drive-using-input-output-feedback-linearization-and-high-order-sliding-mode-control
#6
Abdelkarim Ammar, Amor Bourek, Abdelhamid Benakcha
This paper presents a nonlinear Direct Torque Control (DTC) strategy with Space Vector Modulation (SVM) for an induction motor. A nonlinear input-output feedback linearization (IOFL) is implemented to achieve a decoupled torque and flux control and the SVM is employed to reduce high torque and flux ripples. Furthermore, the control scheme performance is improved by inserting a super twisting speed controller in the outer loop and a load torque observer to enhance the speed regulation. The combining of dual nonlinear strategies ensures a good dynamic and robustness against parameters variation and disturbance...
January 17, 2017: ISA Transactions
https://www.readbyqxmd.com/read/28108002/reduced-order-model-based-active-disturbance-rejection-control-of-hydraulic-servo-system-with-singular-value-perturbation-theory
#7
Chengwen Wang, Long Quan, Shijie Zhang, Hongjun Meng, Yuan Lan
Hydraulic servomechanism is the typical mechanical/hydraulic double-dynamics coupling system with the high stiffness control and mismatched uncertainties input problems, which hinder direct applications of many advanced control approaches in the hydraulic servo fields. In this paper, by introducing the singular value perturbation theory, the original double-dynamics coupling model of the hydraulic servomechanism was reduced to a integral chain system. So that, the popular ADRC (active disturbance rejection control) technology could be directly applied to the reduced system...
January 17, 2017: ISA Transactions
https://www.readbyqxmd.com/read/28107705/incorporation-of-antimicrobial-peptides-in-nanostructured-lipid-membrane-mimetic-bilayer-cubosomes
#8
Thomas G Meikle, Alexandru Zabara, Lynne J Waddington, Frances Separovic, Calum J Drummond, Charlotte E Conn
The inverse bicontinuous lipidic cubic phase offers a simple and robust membrane mimetic with the ability to encapsulate peptides, potentially increasing bioavailability, while also offering a platform from which functionalized, targeted nanoparticles can be developed. Herein we have investigated the use of a number of cubic phase nanoparticle systems with encapsulated antimicrobial peptides gramicidin A', melittin, and alamethicin. The optimal peptide loading ranges, over which cubic symmetry was retained, were determined using small angle X-ray scattering...
January 8, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28107591/the-role-of-autonomic-dysfunction-in-predicting-one-year-mortality-after-liver-transplantation
#9
Kuang-Cheng Chan, Jia-Rong Yeh, Wei-Zen Sun
BACKGROUND & AIMS: Model for end-stage liver disease (MELD) score has been extensively used to prioritize patients for liver transplantation and determine their prognosis, but with limited predictive value. Autonomic dysfunction may correlate with increased mortality after liver transplant. In this study, two autonomic biomarkers, complexity and deceleration capacity, were added to the predicting model for one-year mortality after liver transplantation. METHODS: Thirty patients with end-stage liver diseases awaiting liver transplantation were included...
January 20, 2017: Liver International: Official Journal of the International Association for the Study of the Liver
https://www.readbyqxmd.com/read/28107510/effect-of-the-crystal-environment-on-side-chain-conformational-dynamics-in-cyanovirin-n-investigated-through-crystal-and-solution-molecular-dynamics-simulations
#10
Logan S Ahlstrom, Ivan I Vorontsov, Jun Shi, Osamu Miyashita
Side chains in protein crystal structures are essential for understanding biochemical processes such as catalysis and molecular recognition. However, crystal packing could influence side-chain conformation and dynamics, thus complicating functional interpretations of available experimental structures. Here we investigate the effect of crystal packing on side-chain conformational dynamics with crystal and solution molecular dynamics simulations using Cyanovirin-N as a model system. Side-chain ensembles for solvent-exposed residues obtained from simulation largely reflect the conformations observed in the X-ray structure...
2017: PloS One
https://www.readbyqxmd.com/read/28107505/septic-systems-contribution-to-phosphorus-in-shallow-groundwater-field-scale-studies-using-conventional-drainfield-designs
#11
Sara Mechtensimer, Gurpal S Toor
Septic systems can be a potential source of phosphorus (P) in groundwater and contribute to eutrophication in aquatic systems. Our objective was to investigate P transport from two conventional septic systems (drip dispersal and gravel trench) to shallow groundwater. Two new in-situ drainfields (6.1 m long by 0.61 m wide) with a 3.72 m2 infiltrative surface were constructed. The drip dispersal drainfield was constructed by placing 30.5 cm commercial sand on top of natural soil and the gravel trench drainfield was constructed by placing 30...
2017: PloS One
https://www.readbyqxmd.com/read/28107363/age-dependent-neuroendocrine-signaling-from-sensory-neurons-modulates-the-effect-of-dietary-restriction-on-longevity-of-caenorhabditis-elegans
#12
Marissa Fletcher, Dennis H Kim
Dietary restriction extends lifespan in evolutionarily diverse animals. A role for the sensory nervous system in dietary restriction has been established in Drosophila and Caenorhabditis elegans, but little is known about how neuroendocrine signals influence the effects of dietary restriction on longevity. Here, we show that DAF-7/TGFβ, which is secreted from the C. elegans amphid, promotes lifespan extension in response to dietary restriction in C. elegans. DAF-7 produced by the ASI pair of sensory neurons acts on DAF-1/TGFβ receptors expressed on interneurons to inhibit the co-SMAD DAF-3...
January 20, 2017: PLoS Genetics
https://www.readbyqxmd.com/read/28107341/complex-dynamics-of-virus-spread-from-low-infection-multiplicities-implications-for-the-spread-of-oncolytic-viruses
#13
Ignacio A Rodriguez-Brenes, Andrew Hofacre, Hung Fan, Dominik Wodarz
While virus growth dynamics have been well-characterized in several infections, data are typically collected once the virus population becomes easily detectable. Earlier dynamics, however, remain less understood. We recently reported unusual early dynamics in an experimental system using adenovirus infection of human embryonic kidney (293) cells. Under identical experimental conditions, inoculation at low infection multiplicities resulted in either robust spread, or in limited spread that eventually stalled, with both outcomes occurring with approximately equal frequencies...
January 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28107086/interaction-between-lipid-droplets-and-endoplasmic-reticulum-in-human-atherosclerotic-plaques
#14
Ida Perrotta
Lipid droplets (LDs) are intracellular organelles that are found in nearly all cell types, where they serve fundamental roles in lipid metabolism and energy homeostasis. Traditionally considered as simple lipid storage deposits, these dynamic and remarkable organelles have recently been implicated in a number of other cellular functions, ranging from protein storage and degradation to virus replication. Intracellular accumulation of LDs is also a hallmark feature of diverse human diseases including diabetes type II, obesity, hepatosteatosis, cancer, and atherosclerosis...
January 20, 2017: Ultrastructural Pathology
https://www.readbyqxmd.com/read/28107053/diversity-and-coevolutionary-dynamics-in-high-dimensional-phenotype-spaces
#15
Michael Doebeli, Iaroslav Ispolatov
We study macroevolutionary dynamics by extending microevolutionary competition models to long timescales. It has been shown that for a general class of competition models, gradual evolutionary change in continuous phenotypes (evolutionary dynamics) can be nonstationary and even chaotic when the dimension of the phenotype space in which the evolutionary dynamics unfold is high. It has also been shown that evolutionary diversification can occur along nonequilibrium trajectories in phenotype space. We combine these lines of thinking by studying long-term coevolutionary dynamics of emerging lineages in multidimensional phenotype spaces...
February 2017: American Naturalist
https://www.readbyqxmd.com/read/28107004/microviscosity-offered-by-ionic-liquids-and-ionic-liquid-glycol-mixtures-is-probe-dependent
#16
Anu Kadyan, Siddharth Pandey
Interactions present within the solubilizing media constituted of ionic liquids (ILs) govern the outcomes of chemical processes carried out within such media by controlling the behavior of solutes dissolved therein. Fluidity afforded by IL-based media, in this context, not only reveals interactions present within the system, it also helps decide whether the system is suitable for an application. Response of spectroscopic microviscosity probes dissolved in IL and IL-based solvents, in this regard, reveals information on both solute-solvent and solvent-solvent interactions present within the system...
January 20, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28106979/li-ion-localization-and-energetics-as-a-function-of-anode-structure
#17
Nicholas William McNutt, Marshall T McDonnell, Orlando Rios, David J Keffer
In this work, we study the effect of carbon composite anode structure on the localization and energetics of Li-ions. A computational molecular dynamics study is combined with experimental results from neutron scattering experiments to understand the effect of composite density, crystallite size, volume fraction of crystalline carbon, and ion loading on the nature of ion storage in novel, lignin-derived composite materials. In a recent work1, we demonstrated that these carbon composites display a fundamentally different mechanism for Li-ion storage than traditional graphitic anodes...
January 20, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28106823/integrated-microrna-mrna-profiling-identifies-oncostatin-m-as-a-marker-of-mesenchymal-like-er-negative-her2-negative-breast-cancer
#18
Giulia Bottai, Lixia Diao, Keith A Baggerly, Laura Paladini, Balázs Győrffy, Carlotta Raschioni, Lajos Pusztai, George A Calin, Libero Santarpia
MicroRNAs (miRNAs) simultaneously modulate different oncogenic networks, establishing a dynamic system of gene expression and pathway regulation. In this study, we analyzed global miRNA and messenger RNA (mRNA) expression profiles of 17 cell lines representing different molecular breast cancer subtypes. Spearman's rank correlation test was used to evaluate the correlation between miRNA and mRNA expression. Hierarchical clustering and pathway analysis were also performed. Publicly available gene expression profiles (n = 699) and tumor tissues (n = 80) were analyzed to assess the relevance of key miRNA-regulated pathways in human breast cancer...
January 19, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28106453/giant-amplification-of-noise-in-fluctuation-induced-pattern-formation
#19
Tommaso Biancalani, Farshid Jafarpour, Nigel Goldenfeld
The amplitude of fluctuation-induced patterns might be expected to be proportional to the strength of the driving noise, suggesting that such patterns would be difficult to observe in nature. Here, we show that a large class of spatially extended dynamical systems driven by intrinsic noise can exhibit giant amplification, yielding patterns whose amplitude is comparable to that of deterministic Turing instabilities. The giant amplification results from the interplay between noise and nonorthogonal eigenvectors of the linear stability matrix, yielding transients that grow with time, and which, when driven by the ever-present intrinsic noise, lead to persistent large amplitude patterns...
January 6, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28106441/loschmidt-echo-revivals-critical-and-noncritical
#20
R Jafari, Henrik Johannesson
A quantum phase transition is generally thought to imprint distinctive characteristics on the nonequilibrium dynamics of a closed quantum system. Specifically, the Loschmidt echo after a sudden quench to a quantum critical point-measuring the time dependence of the overlap between initial and time-evolved states-is expected to exhibit an accelerated relaxation followed by periodic revivals. We here introduce a new exactly solvable model, the extended Su-Schrieffer-Heeger model, the Loschmidt echo of which provides a counterexample...
January 6, 2017: Physical Review Letters
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