Read by QxMD icon Read

Constraint based modeling

Jacqueline E Gonzalez, Maciek R Antoniewicz
Engineered microbes offer a practical and sustainable alternative to traditional industrial approaches. To increase the economic feasibility of biological processes, microbial isolates are engineered to take up inexpensive feedstocks (including lignocellulosic biomass, syngas, methane, and carbon dioxide), and convert them into substrates of central metabolism and further into value-added products. To trace the metabolism of these feedstocks into products, isotopic tracers are applied together with isotopomer analysis techniques such as (13)C-metabolic flux analysis to provide a detailed picture of pathway utilization...
October 22, 2016: Current Opinion in Biotechnology
Saturnin Bertrand Nguenda Anya, Atanase Yene
This paper seeks to identify the determinants of the choice of treatment of pregnant women in Cameroon. Theoretically, the methodology is based on a discrete choice model with random utility. Empirically, the econometric specification is a Nested Multinomial Logit Model. The data used comes from the Demographic Health Survey (DHS) organized in 2011 by the National Institute of Statistics. The results reveal that uneducated women or those having only a primary education prefer to meet the traditional midwives than seek modern maternal health services...
December 2016: Health Economics Review
Biswaranjan Mohanty, Martin L Williams, Bradley C Doak, Mansha Vazirani, Olga Ilyichova, Geqing Wang, Wolfgang Bermel, Jamie S Simpson, David K Chalmers, Glenn F King, Mehdi Mobli, Martin J Scanlon
We describe a general approach to determine the binding pose of small molecules in weakly bound protein-ligand complexes by deriving distance constraints between the ligand and methyl groups from all methyl-containing residues of the protein. We demonstrate that using a single sample, which can be prepared without the use of expensive precursors, it is possible to generate high-resolution data rapidly and obtain the resonance assignments of Ile, Leu, Val, Ala and Thr methyl groups using triple resonance scalar correlation data...
October 24, 2016: Journal of Biomolecular NMR
N Foray
On the 4th July, 1896, in his medical office of Les Échelles (Savoie, France), Victor Despeignes performed the very first radiotherapy against cancer, documented by indisputable proofs. However, the intellectual and practical approach that leads to this first radiotherapy may appear unexpected to date. Indeed, it is likely that the treatment that Despeignes applied to his neighbour, who did not suffer from stomach cancer, was born with the indirect support of the Lumière brothers, on the basis of a biological theory (the parasitory theory of cancer) that is irrelevant today, with an experimental protocol based on experiments performed on tuberculosis et in a bifractionated model linked by the constraints of a district medical doctor...
October 21, 2016: Cancer Radiothérapie: Journal de la Société Française de Radiothérapie Oncologique
Peter R Wiecha, Arnaud Arbouet, Christian Girard, Aurélie Lecestre, Guilhem Larrieu, Vincent Paillard
The rational design of photonic nanostructures consists of anticipating their optical response from systematic variations of simple models. This strategy, however, has limited success when multiple objectives are simultaneously targeted, because it requires demanding computational schemes. To this end, evolutionary algorithms can drive the morphology of a nano-object towards an optimum through several cycles of selection, mutation and cross-over, mimicking the process of natural selection. Here, we present a numerical technique that can allow the design of photonic nanostructures with optical properties optimized along several arbitrary objectives...
October 24, 2016: Nature Nanotechnology
Reddi Kamesh, Kalipatnapu Yamuna Rani
In this paper, a novel formulation for nonlinear model predictive control (MPC) has been proposed incorporating the extended Kalman filter (EKF) control concept using a purely data-driven artificial neural network (ANN) model based on measurements for supervisory control. The proposed scheme consists of two modules focusing on online parameter estimation based on past measurements and control estimation over control horizon based on minimizing the deviation of model output predictions from set points along the prediction horizon...
October 13, 2016: IEEE Transactions on Neural Networks and Learning Systems
Danilo T Perez-Rivera, Veronica L Torres-Torres, Abraham E Torres-Colon, Maytee Cruz-Aponte
Diabetes mellitus is a disease characterized by a range of metabolic complications involving an individual's blood glucose levels, and its main regulator, insulin. These complications can vary largely from person to person depending on their current biophysical state. Biomedical research day-by-day makes strides to impact the lives of patients of a variety of diseases, including diabetes. One large stride that is being made is the generation of techniques to assist physicians to ``personalize medicine''. From available physiological data, biological understanding of the system, and dimensional analysis, a differential equation-based mathematical model was built in a sequential matter, to be able to elucidate clearly how each parameter correlates to the patient's current physiological state...
October 1, 2016: Mathematical Biosciences and Engineering: MBE
Joachim Niehren, Cristian Versari, Mathias John, François Coutte, Philippe Jacques
We wish to predict changes of reaction networks with partial kinetic information that lead to target changes of their steady states. The changes may be either increases or decreases of influxes, reaction knockouts, or multiple changes of these two kinds. Our prime applications are knockout prediction tasks for metabolic and regulation networks. In a first step, we propose a formal modeling language for reaction networks with partial kinetic information. The modeling language has a graphical syntax reminiscent to Petri nets...
October 18, 2016: Bio Systems
David J McKenzie, Michael Axelsson, Denis Chabot, Guy Claireaux, Steven J Cooke, Richard A Corner, Gudrun De Boeck, Paolo Domenici, Pedro M Guerreiro, Bojan Hamer, Christian Jørgensen, Shaun S Killen, Sjannie Lefevre, Stefano Marras, Basile Michaelidis, Göran E Nilsson, Myron A Peck, Angel Perez-Ruzafa, Adriaan D Rijnsdorp, Holly A Shiels, John F Steffensen, Jon C Svendsen, Morten B S Svendsen, Lorna R Teal, Jaap van der Meer, Tobias Wang, Jonathan M Wilson, Rod W Wilson, Julian D Metcalfe
The state of the art of research on the environmental physiology of marine fishes is reviewed from the perspective of how it can contribute to conservation of biodiversity and fishery resources. A major constraint to application of physiological knowledge for conservation of marine fishes is the limited knowledge base; international collaboration is needed to study the environmental physiology of a wider range of species. Multifactorial field and laboratory studies on biomarkers hold promise to relate ecophysiology directly to habitat quality and population status...
2016: Conservation Physiology
Qie He, Junfeng Zhu, David Dingli, Jasmine Foo, Kevin Zox Leder
Over the past decade, several targeted therapies (e.g. imatinib, dasatinib, nilotinib) have been developed to treat Chronic Myeloid Leukemia (CML). Despite an initial response to therapy, drug resistance remains a problem for some CML patients. Recent studies have shown that resistance mutations that preexist treatment can be detected in a substantial number of patients, and that this may be associated with eventual treatment failure. One proposed method to extend treatment efficacy is to use a combination of multiple targeted therapies...
October 2016: PLoS Computational Biology
Jostein Gohli, Kjetil L Voje
BACKGROUND: Bergmann's rule proposes that animals in cold habitats will be larger than those in warm habitats. This prediction has been tested thoroughly at the intraspecific level, but few studies have investigated the hypothesis with interspecific data using phylogenetic comparative approaches. Many clades of mammals have representatives in numerous distinct biomes, making this order highly suitable for a large-scale interspecific assessment of Bergmann's rule. Here, we evaluate Bergmann's rule within 22 mammalian families-with a dataset that include ~35 % of all described species-using a phylogenetic comparative approach...
October 19, 2016: BMC Evolutionary Biology
Mark O'Driscoll
Accurate and efficient replication of the human genome occurs in the context of an array of constitutional barriers including regional topological constraints imposed by chromatin architecture and processes such as transcription, catenation of the helical polymer and spontaneously generated DNA lesions including base modifications and strand breaks. DNA replication is fundamentally important for tissue development and homeostasis; differentiation programmes are intimately linked with stem cell division. Unsurprisingly, impairments of the DNA replication machinery can have catastrophic consequences for genome stability and cell division...
October 18, 2016: Journal of Pathology
Linda J Gormezano, Scott R McWilliams, David T Iles, Robert F Rockwell
Trade-offs between locomotory costs and foraging gains are key elements in determining constraints on predator-prey interactions. One intriguing example involves polar bears pursuing snow geese on land. As climate change forces polar bears to spend more time ashore, they may need to expend more energy to obtain land-based food. Given that polar bears are inefficient at terrestrial locomotion, any extra energy expended to pursue prey could negatively impact survival. However, polar bears have been regularly observed engaging in long pursuits of geese and other land animals, and the energetic worth of such behaviour has been repeatedly questioned...
2016: Conservation Physiology
Mohammad Hossein Mehrolhasani, Sajad Khosravi, Mahya Tohidi
INTRODUCTION: In order to improve health, hospital sources such as beds and staffing should be properly allocated and used. The aim of this study is reallocation of Shafa hospital beds in Kerman using a goal-programming model. METHODS: This study was an applied cross-sectional study, which used the goal programming model and software WinQSB to optimize bed allocation. By review of the literature and interviews with experts, the constraints in beds allocation were identified, and using the collected data the desired model was designed...
August 2016: Electronic Physician
Henry Zakumumpa, Modupe Oladunni Taiwo, Alex Muganzi, Freddie Ssengooba
BACKGROUND: Human resources for health (HRH) constraints are a major barrier to the sustainability of antiretroviral therapy (ART) scale-up programs in Sub-Saharan Africa. Many prior approaches to HRH constraints have taken a top-down trend of generalized global strategies and policy guidelines. The objective of the study was to examine the human resources for health strategies adopted by front-line providers in Uganda to sustain ART delivery beyond the initial ART scale-up phase between 2004 and 2009...
October 19, 2016: Human Resources for Health
Álvaro Franco-Giraldo
This article presents a Latin American vision of global health from a counterhegemonic perspective, applicable to various countries of the world in similar circumstances. It begins by reviewing several concepts and trends in global health and outlining the differences between conventional public health, international health, and global health, but without seeing them as antagonistic, instead situating them in a model that is based on global health and also includes the other two disciplines. It is understood that global factors influenced earlier theories, schemes, and models of classic international health...
February 2016: Revista Panamericana de Salud Pública, Pan American Journal of Public Health
Peter Rijnbeek
Massive numbers of electronic health records are currently being collected globally, including structured data in the form of diagnoses, medications, laboratory test results, and unstructured data contained in clinical narratives. This opens unprecedented possibilities for research and ultimately patient care. However, actual use of these databases in a multi-center study is severely hampered by a variety of challenges, e.g., each database has a different database structure and uses different terminology systems...
September 2016: Journal of Hypertension
Miguel Pinto, Vítor Borges, Minia Antelo, Miguel Pinheiro, Alexandra Nunes, Jacinta Azevedo, Maria José Borrego, Joana Mendonça, Dina Carpinteiro, Luís Vieira, João Paulo Gomes
Insights into the genomic adaptive traits of Treponema pallidum, the causative bacterium of syphilis, have long been hampered due to the absence of in vitro culture models and the constraints associated with its propagation in rabbits. Here, we have bypassed the culture bottleneck by means of a targeted strategy never applied to uncultivable bacterial human pathogens to directly capture whole-genome T. pallidum data in the context of human infection. This strategy has unveiled a scenario of discreet T. pallidum interstrain single-nucleotide-polymorphism-based microevolution, contrasting with a rampant within-patient genetic heterogeneity mainly targeting multiple phase-variable loci and a major antigen-coding gene (tprK)...
October 17, 2016: Nature Microbiology
Juan Antonio Campos, Gonzalo García-Baquero, Lidia Caño, Idoia Biurrun, Itziar García-Mijangos, Javier Loidi, Mercedes Herrera
Alien species invasion represents a global threat to biodiversity and ecosystems. Explaining invasion patterns in terms of environmental constraints will help us to assess invasion risks and plan control strategies. We aim to identify plant invasion patterns in the Basque Country (Spain), and to determine the effects of climate and human pressure on that pattern. We modeled the regional distribution of 89 invasive plant species using two approaches. First, distance-based Moran's eigenvector maps were used to partition variation in the invasive species richness, S, into spatial components at broad and fine scales; redundancy analysis was then used to explain those components on the basis of climate and human pressure descriptors...
2016: PloS One
Takahiro Ogawa, Miki Haseyama
This paper presents adaptive subspace-based inverse projections via division into multiple sub-problems (ASIP-DIMS) for missing image data restoration. In the proposed method, a target problem for estimating missing image data is divided into multiple sub-problems, and each sub-problem is iteratively solved with constraints of other known image data. By projection into a subspace model of image patches, the solution of each subproblem is calculated, where we call this procedure "subspacebased inverse projection" for simplicity...
October 10, 2016: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"