Об использовании элементов метода ветвей и границ в схемах динамического программирования

Рассматривается возможный способ повышения эффективности алгоритмов по методу динамического программирования при решении условных экстремальных задач с аддитивными целевыми функциями, заданными на дискретных множествах. Основной идеей рассматриваемого способа является сокращение областей определения экстремума при решении рекуррентных уравнений Беллмана путем сравнения текущих значений функции Беллмана с рекордом, аналогично схеме метода ветвей и границ

Conductive cotton prepared by polyaniline in situ polymerization using laccase

The high-redox-potential catalyst laccase, isolated from Aspergillus, was first used as a biocatalyst in the oxidative polymerization of water-soluble conductive polyaniline, and then conductive cotton was prepared by in situ polymerization under the same conditions. The polymerization of aniline was performed in a water dispersion of sodium dodecylbenzenesulfonate (SDBS) micellar solution with atmospheric oxygen serving as the oxidizing agent. This method is ecologically clean and permits a greater degree of control over the kinetics of the reaction. The conditions for polyaniline synthesis were optimized. Characterizations of the conducting polyaniline and cotton were carried out using Fourier transform infrared spectroscopy, UV–vis spectroscopy, cyclic voltammetry, the fabric induction electrostatic tester, and the far-field EMC shielding effectiveness test fixture.This work was financially supported by the National Natural Science Foundation of China (21274055, 51173071), the Program for New Century Excellent Talents in University (NCET-12-0883), the Natural Science Foundation of Jiangsu Province (BK2011157), the Fundamental Research Funds for the Central Universities (JUSRP51312B), and the Program for Changjiang Scholars and Innovative Research Team in University (IRT1135)

An Automated Phenotype-Driven Approach (GeneForce) for Refining Metabolic and Regulatory Models

Integrated constraint-based metabolic and regulatory models can accurately predict cellular growth phenotypes arising from genetic and environmental perturbations. Challenges in constructing such models involve the limited availability of information about transcription factor—gene target interactions and computational methods to quickly refine models based on additional datasets. In this study, we developed an algorithm, GeneForce, to identify incorrect regulatory rules and gene-protein-reaction associations in integrated metabolic and regulatory models. We applied the algorithm to refine integrated models of Escherichia coli and Salmonella typhimurium, and experimentally validated some of the algorithm's suggested refinements. The adjusted E. coli model showed improved accuracy (∼80.0%) for predicting growth phenotypes for 50,557 cases (knockout mutants tested for growth in different environmental conditions). In addition to identifying needed model corrections, the algorithm was used to identify native E. coli genes that, if over-expressed, would allow E. coli to grow in new environments. We envision that this approach will enable the rapid development and assessment of genome-scale metabolic and regulatory network models for less characterized organisms, as such models can be constructed from genome annotations and cis-regulatory network predictions

Vivências maternas associadas ao aleitamento materno exclusivo mais duradouro: um estudo etnográfico

OBJETIVO: Descrever as experiências da amamentação de mães usuárias do Sistema Único de Saúde buscando, tanto aprender conhecimentos, expectativas, concepções e sentimentos envolvidos como identificar aspectos relevantes para o aleitamento materno exclusivo mais prolongado. MÉTODOS: Estudo qualitativo de cunho etnográfico realizado com oito primíparas e familiares de referência, mediante observação e entrevistas domiciliares durante o 1º semestre de vida dos bebês. Os dados foram sistematizados em três categorias: Iniciando a amamentação; Vivenciando o processo de desmame precoce; Mantendo o aleitamento materno exclusivo. RESULTADOS: A amamentação apresentou-se como evento particular nos diferentes contextos de sua ocorrência, porém foi possível identificar que o aleitamento exclusivo esteve ligado à determinação materna, a despeito das dificuldades vividas. O aleitamento materno exclusivo mais duradouro relacionou-se às mães que se mostraram motivadas com a prática, cientes de seus benefícios e apoiadas pela família, mesmo diante de interferência contrária de seu meio cultural. CONCLUSÃO: A ausência de determinação materna em amamentar exclusivamente deve ser investigada e, quando presente, receber abordagem especial pelos profissionais de saúde.OBJETIVO: Describir las experiencias del amamantamiento de madres usuarias del Sistema Único de Salud buscando, tanto aprender conocimientos, expectativas, concepciones y sentimientos involucrados como identificar aspectos relevantes para la lactancia materno exclusiva más prolongada. MÉTODOS: Estudio cualitativo de cuño etnográfico realizado con ocho primíparas y familiares de referencia, mediante observación y entrevistas domiciliarias durante el 1º semestre de vida de los bebés. Los datos fueron sistematizados en tres categorías: Iniciando el amamantamiento; Vivenciando el proceso de destete precoz; Manteniendo La lactancia materna exclusiva. RESULTADOS: El amamantamiento se presentó como evento particular en los diferentes contextos de su ocurrencia, sin embargo fue posible identificar que la lactancia exclusiva estuvo ligado a la determinación materna, a pesar de las dificultades vividas. La lactancia materna exclusiva más duradera se relacionó a las madres que se mostraron motivadas con la práctica, concientes de sus beneficios y apoyadas por la familia, aun frente a la interferencia contraria de su medio cultural. CONCLUSIÓN: La ausencia de determinación materna para amamantar exclusivamente debe ser investigada y, cuando presente, recibir abordaje especial de los profesionales de salud.OBJECTIVE: To describe the experiences of breastfeeding mothers using the Unified Health System who were seeking to obtain knowledge, expectations, perceptions and feelings involved with identifying aspects relevant for more prolonged, exclusive breastfeeding. METHODS: A qualitative ethnographic study conducted with eight primiparas and family references, through observation and household interviews during the first semester of the infants' lives. The data were summarized in three categories: starting breastfeeding; experiencing the process of early weaning; maintaining exclusive breastfeeding. RESULTS: Breastfeeding appeared as a particular event in different contexts of occurrence, however, it was possible to identify that exclusive breastfeeding was linked to maternal determination, despite the difficulties experienced. Longer lasting exclusive breastfeeding was related to the mothers who were highly motivated to practice, those who were aware of its benefits and were supported by their family, even in the face of interference contrary to their culture. CONCLUSION: The lack of determination for exclusive maternal breastfeeding should be investigated and, when present, receive special consideration by health professionals

A Coevolutionary Residue Network at the Site of a Functionally Important Conformational Change in a Phosphohexomutase Enzyme Family

Coevolution analyses identify residues that co-vary with each other during evolution, revealing sequence relationships unobservable from traditional multiple sequence alignments. Here we describe a coevolutionary analysis of phosphomannomutase/phosphoglucomutase (PMM/PGM), a widespread and diverse enzyme family involved in carbohydrate biosynthesis. Mutual information and graph theory were utilized to identify a network of highly connected residues with high significance. An examination of the most tightly connected regions of the coevolutionary network reveals that most of the involved residues are localized near an interdomain interface of this enzyme, known to be the site of a functionally important conformational change. The roles of four interface residues found in this network were examined via site-directed mutagenesis and kinetic characterization. For three of these residues, mutation to alanine reduces enzyme specificity to ∼10% or less of wild-type, while the other has ∼45% activity of wild-type enzyme. An additional mutant of an interface residue that is not densely connected in the coevolutionary network was also characterized, and shows no change in activity relative to wild-type enzyme. The results of these studies are interpreted in the context of structural and functional data on PMM/PGM. Together, they demonstrate that a network of coevolving residues links the highly conserved active site with the interdomain conformational change necessary for the multi-step catalytic reaction. This work adds to our understanding of the functional roles of coevolving residue networks, and has implications for the definition of catalytically important residues

Dry Needling for Spine Related Disorders: a Scoping Review

Introduction/Background: The depth and breadth of research on dry needling (DN) has not been evaluated specifically for symptomatic spine related disorders (SRD) from myofascial trigger points (TrP), disc, nerve and articular structures not due to serious pathologies. Current literature appears to support DN for treatment of TrP. Goals of this review include identifying research published on DN treatment for SRD, sites of treatment and outcomes studied. Methods: A scoping review was conducted following Levac et al.’s five part methodological framework to determine the current state of the literature regarding DN for patients with SRD. Results: Initial and secondary search strategies yielded 55 studies in the cervical (C) region (71.43%) and 22 in the thoracolumbar-pelvic (TLP) region (28.57%). Most were randomized controlled trials (60% in C, 45.45% in TLP) and clinical trials (18.18% in C, 22.78% in TLP). The most commonly treated condition was TrP for both the C and TLP regions. In the C region, DN was provided to 23 different muscles, with the trapezius as treatment site in 41.88% of studies. DN was applied to 31 different structures in the TLP region. In the C region, there was one treatment session in 23 studies (41.82%) and 2–6 treatments in 25 (45.45%%). For the TLP region, one DN treatment was provided in 8 of the 22 total studies (36.36%) and 2–6 in 9 (40.9%). The majority of experimental designs had DN as the sole intervention. For both C and TLP regions, visual analogue scale, pressure pain threshold and range of motion were the most common outcomes. Conclusion: For SRD, DN was primarily applied to myofascial structures for pain or TrP diagnoses. Many outcomes were improved regardless of diagnosis or treatment parameters. Most studies applied just one treatment which may not reflect common clinical practice. Further research is warranted to determine optimal treatment duration and frequency. Most studies looked at DN as the sole intervention. It is unclear whether DN alone or in addition to other treatment procedures would provide superior outcomes. Functional outcome tools best suited to tracking the outcomes of DN for SRD should be explored.https://doi.org/10.1186/s12998-020-00310-