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1
K, Toungara. "Contribution à l'amélioration de la qualité de prise en charge du paludisme au Centre de Santé Communautaire de Sanankoroba dans le district sanitaire de Kalabancoro, Mali". Mali Santé Publique 10, n. 02 (20 aprile 2021): 34–39. http://dx.doi.org/10.53318/msp.v10i02.1794.
Abstract (sommario):
Introduction : Le paludisme constitue un véritable problème de santé publique dans le monde et majeur dans les pays subsahariens. Sa prise en charge selon les recommandations de l'OMS n'est pas correctement effectuée partout. Le but de notre travail était de contribuer à l'amélioration de la qualité de la prise en charge du paludisme dans le centre de santé communautaire de Sanankoroba. Matériel et méthodes : Il s'agissait d'une étude transversale à passage répété de recherche action de Susman. Elle s'est déroulée en quatre mois allant du 1ier juillet au 31 octobre 2019 dans le centre de santé de Sanankoroba. Ont été inclus dans cette étude les cas présumés ou confirmés du paludisme par les prestataires de santé du CSCom de Sanankoroba. Résultats : Après la mise en place du plan d'action entre l'évaluation initiale et finale, nous avons constaté une évolution de la concordance entre signes et classification du paludisme de 51% à 93,3% (Chi2 = 40,848 ; p<10-3). Le suivi et l'évolution appliqués par les prestataires étaient passés de 0% à 82,7% (Chi2 = 105,7 ; p = 0,765) au cours de l'évaluation finale. Les conseils sur les mesures de prévention de 0% à 81.3 % après le plan d'action. Conclusion : Les insuffisances constatées au cours de cette étude ont été corrigées grâce à des planifications faites et leur mise en œuvre.Mots clés : paludisme, centre de santé communautaire, Sanankoroba, Mali
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Angelova, Lyudmila, Maria Tsvetkova e Mariya Levkova. "CHROMOSOMAL POLYMORPHISM IN BULGARIAN PATIENTS WITH REPRODUCTIVE PROBLEMS – ONE GENETIC CENTRE EXPERIENCE". Journal of IMAB - Annual Proceeding (Scientific Papers) 27, n. 4 (2 dicembre 2021): 4133–38. http://dx.doi.org/10.5272/jimab.2021274.4133.
Abstract (sommario):
Chromosomal polymorphism is described as normal variants at chromosomal regions with no impact on the phenotype but a possible correlation to infertility and recurrent spontaneous abortions. The aim of this study was to evaluate the effect of the chromosomal polymorphisms involved in families with reproductive failures in the Bulgarian population. Material and methods: A total of 1733 patients with unexplained reproductive failures who visited the Laboratory of Medical Genetics – Varna, Bulgaria, (2004 - 2019) were investigated by conventional cytogenetic analysis GTG and CBG differential banding techniques and analyzed at the resolution 400-550 GTG bands. Results: Chromosomal polymorphisms were found in 173 infertile patients (9,98%). The sex distribution was 6,52% males and 3,46% females. The most frequent finding was inv(9)(qh) (23,7%). The other chromosomal variants, which were found, consisted: 9qh+/- variants (15,1%); polymorphisms on the short arms of the acrocentric chromosomes (21,4%); 16qh+ (12,7%) and 1qh+ (6,9%). Y chromosome polymorphism was found in 27,4% of the males with polymorphisms. Two rare cases of polymorphism involving the centromere regions - 19qcenh+ and 20pcenh+ were also found. Conclusion: There is growing evidence that polymorphisms may have a clinical impact on fertility and could take part in the etiology of RF. In this study, we found a significantly high percentage of polymorphisms (9,98%) among the tested patients, and they were more common among males. The statistical significance of increased incidence of chromosome variations found in our study emphasizes the need for routine evaluation of their role in families with RF in our country.
3
Lima de Paulo, Wanderlei, Marta Ines Velazco Fontova e Renato Canil de Souza. "An analysis of a mean-variance enhanced index tracking problem with weights constraints". Investment Management and Financial Innovations 15, n. 4 (19 novembre 2018): 183–92. http://dx.doi.org/10.21511/imfi.15(4).2018.15.
Abstract (sommario):
In this paper, the authors deal with a mean-variance enhanced index tracking (EIT) problem with weights constraints. Using a shrinkage approach, they show that constructing the constrained EIT portfolio is equivalent to constructing the unconstrained EIT portfolio. This equivalence allows to study the effect of weights constraints on the covariance matrix and on the EIT portfolio. In general, the effects of weights constraints on the EIT portfolio are different from those observed in the case of global minimum variance portfolio. Finally, the authors present a numerical asset allocation example, where the S&amp;P 500 index is used as the market index to be tracked using a portfolio composed of ten stocks, in which the constrained EIT portfolio shows a satisfactory performance when compared to the unconstrained case.
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Dupin, Nicolas, Frank Nielsen e El-Ghazali Talbi. "Unified Polynomial Dynamic Programming Algorithms for P-Center Variants in a 2D Pareto Front". Mathematics 9, n. 4 (23 febbraio 2021): 453. http://dx.doi.org/10.3390/math9040453.
Abstract (sommario):
With many efficient solutions for a multi-objective optimization problem, this paper aims to cluster the Pareto Front in a given number of clusters K and to detect isolated points. K-center problems and variants are investigated with a unified formulation considering the discrete and continuous versions, partial K-center problems, and their min-sum-K-radii variants. In dimension three (or upper), this induces NP-hard complexities. In the planar case, common optimality property is proven: non-nested optimal solutions exist. This induces a common dynamic programming algorithm running in polynomial time. Specific improvements hold for some variants, such as K-center problems and min-sum K-radii on a line. When applied to N points and allowing to uncover M<N points, K-center and min-sum-K-radii variants are, respectively, solvable in O(K(M+1)NlogN) and O(K(M+1)N2) time. Such complexity of results allows an efficient straightforward implementation. Parallel implementations can also be designed for a practical speed-up. Their application inside multi-objective heuristics is discussed to archive partial Pareto fronts, with a special interest in partial clustering variants.
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YANG, LINMIN, ZHE DANG e OSCAR H. IBARRA. "ON STATELESS AUTOMATA AND P SYSTEMS". International Journal of Foundations of Computer Science 19, n. 05 (ottobre 2008): 1259–76. http://dx.doi.org/10.1142/s0129054108006261.
Abstract (sommario):
We introduce the notion of stateless multihead two-way (respectively, one-way) NFAs and stateless multicounter systems and relate them to P systems and vector addition systems. In particular, we investigate the decidability of the emptiness and reachability problems for these stateless automata and show that the results are applicable to similar questions concerning certain variants of P systems, namely, token systems and sequential tissue-like P systems.
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Sáez-Aguado, Jesús, e Paula Camelia Trandafir. "Variants of the $$ \varepsilon $$ ε -constraint method for biobjective integer programming problems: application to p-median-cover problems". Mathematical Methods of Operations Research 87, n. 2 (22 ottobre 2017): 251–83. http://dx.doi.org/10.1007/s00186-017-0618-9.
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Andrei, Ionica. "Existence Theorems for Some Classes of Boundary Value Problems Involving the P(X)-Laplacian". Nonlinear Analysis: Modelling and Control 13, n. 2 (25 aprile 2008): 145–58. http://dx.doi.org/10.15388/na.2008.13.2.14575.
Abstract (sommario):
We prove an alternative for a nonlinear eigenvalue problem involving the p(x)-Laplacian and study a subcritical boundary value problem for the same operator. The theoretical approach is the Mountain Pass Lemma and one of its variants, which is very useful in the study of eigenvalue problems.
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Захаров, И. В., В. Г. Терехов, А. Н. Соколовский e С. С. Зыкова. "Reconfiguration of the on-board complex of a mobile object based on modeling of variants of its structural degradation". Vestnik of Russian New University. Series «Complex systems: models, analysis, management», n. 4 (23 gennaio 2023): 41–48. http://dx.doi.org/10.18137/rnu.v9187.22.04.p.39.
Abstract (sommario):
Решение задач применения бортовых вычислительных комплексов подвижных объектов в условиях влияния неблагоприятных факторов различного происхождения требует гибкого управления режимами работы. Предлагаемый способ функционально-параметрического конфигурирования бортовых вычислительных комплексов подвижных объектов основан на оперативном управлении составом выполняемых задач и параметрами функционирования элементов бортовых вычислительных комплексов на основе анализа ресурса системы, условий функционирования и прогнозирования ее состояния. Solving the problems of using on-board computing systems of mobile objects under the influence of adverse factors of various origins requires flexible control of operating modes. The proposed method of functional parametric configuration of on-board computing complexes of mobile objects is based on operational management of the composition of tasks performed and the parameters of the functioning of the elements of on-board computing complexes based on the analysis of the system resource, operating conditions and forecasting of its condition.
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Hampl, Martin. "Territorial Administrative Division of Czech Republic - Conception Problems and Variants of Solution". Geografie 95, n. 4 (1990): 248–59. http://dx.doi.org/10.37040/geografie1990095040248.
Abstract (sommario):
The paper deals with general problems and possible variants of solution of the new territorial administrative arrangement. A special attention is paid to the application of geographical knowledge, especially the results of the social-geographical regionalization in the solution of these problems. Apart from general problems, variants on central, regional and local levels are dealt with in more detail.
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Diallo, MB, e Et Al. "Séroprévalence de l’hépatite B chez les femmes enceintes en consultation prénatale au centre de sante urbain Mafoudia de Dubreka (République de Guinée)." Revue Malienne d'Infectiologie et de Microbiologie 18, n. 1 (23 giugno 2023): 6–10. http://dx.doi.org/10.53597/remim.v18i1.2623.
Abstract (sommario):
Introduction : Le virus de l’hépatite B (VHB) est un virus à ADN enveloppé, de la famille des Hepadnaviridae. Elle est l’une des maladies infectieuses les plus courantes dans le monde. On estime qu'il y a 350 millions de porteurs chroniques du virus de l'hépatite B (VHB) dans le monde avec un risque important chez les femmes enceintes. La présente étude avait pour but d’évaluer la séroprévalence de l’AgHBs chez les femmes enceintes reçues en consultation prénatale au centre de sante urbain Mafoudia de Dubreka. Méthode : Il s'agissait d'une étude transversale d’une durée de trois (03) mois allant du 18 novembre 2020 au 18 février 2021. Résultats : Durant cette étude, nous avons testé 250 femmes enceintes venues en consultation prénatale au centre de santé, une séroprévalence de 10,6% a été obtenue. La tranche d’âge de 15-24 ans était la plus représentée avec 8,6% des cas. Les femmes fonctionnaires étaient les plus touchées avec 16,7%. Les universitaires étaient les plus représentés avec 20,8%. La plupart des femmes enceintes étaient au 3ème trimestre avec 13.7% des cas. Les facteurs de risques associés à ce portage sont entre autres les soins dentaires, piercing et les comportements sexuels à risques avec p ≤ 0,05. Conclusion : Notre étude montre que l’hépatite B représente bien un problème de santé publique chez les gestantes de la ville de Dubréka. Ce constat a pour conséquence d’impacter significativement dans la prise en charge des nouveaux nés sur le plan clinique et économique dans un contexte de pays à ressources limitées
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Cohen, Seymour R., e Jerome W. Thompson. "Variants of Möbius' Syndrome and Central Neurologic Impairment". Annals of Otology, Rhinology & Laryngology 96, n. 1 (gennaio 1987): 93–100. http://dx.doi.org/10.1177/000348948709600122.
Abstract (sommario):
Möbius' syndrome is a complex neurologic disorder; its etiology and characterization have eluded clinicians for over a century. The pure Möbius' syndrome is rare, and the involvement of the sixth and seventh nerves has been found to have a host of associated defects. These include 1) limb and shoulder abnormalities; 2) multiple cranial nerve defects; 3) occasional mental retardation; 4) external, middle, and inner ear abnormalities; 5) laryngeal neurologic defects that cause stridor, obstruction, and aspiration; and 6) severe dysphagia and associated aspiration with life-threatening pneumonias. The children with severe neurologic dysfunction from central nuclear deficiencies were in many respects so similar in their clinical course that they are included in this paper. All of the patients required a tracheotomy to support the airway and to permit tracheobronchial toilet. A feeding gastrostomy was necessary in all but one patient. To counter life-threatening aspiration in the patients with multiple CNS defects, the Lindeman laryngeal diversion was considered the procedure of choice and proved very effective. The details and problems of this procedure are discussed. The aural defects and laryngeal findings in this series of patients are described in detail.
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Soumare, M., e Et Al. "Aspects radiologiques de la tuberculose pulmonaire chez les patients vivant avec le virus d’immunodéficience humaine dans les services de Maladies infectieuses et de Pneumophtisiologie du centre hospitalier universitaire Point G de Bamako". Revue Malienne d'Infectiologie et de Microbiologie 17, n. 2 (2 dicembre 2022): 54–60. http://dx.doi.org/10.53597/remim.v17i2.2783.
Abstract (sommario):
Introduction : la tuberculose constitue un problème majeur de santé publique dans les pays en développement où son incidence est augmentée par l’infection au VIH. Notre objectif principal était de déterminer l’aspect radiologique prédominant et sa relation avec le degré d’immunodépression chez les co-infectés TB/VIH. Méthodes : il s’agissait d’une étude rétrospective analytique descriptive, allant du 1er janvier 2015 au 30 juin 2017, portant sur les co-infectés TB/VIH hospitalisés dans les services de Maladies infectieuses et Pneumophtisiologie du CHU Point G de Bamako, disposant d’un cliché radiologique et d’un dossier, exploitables. L’échantillonnage était exhaustif et les données recueillies ont été saisies et analysées à l’aide du logiciel SPSS 21.0. La comparaison des proportions a été faite par le test d’association khi carré de Pearson significatif si p<0,05. Résultats : la fréquence de la co-infection TB/VIH était de 3,5%. La majorité des patients avaient un CD4<200cellules/μl (88,2%). La bacilloscopie et le Gène Xpert étaient négatifs dans respectivement 85.3 et 52.9% des cas et significativement influencés par l’immunodépression sévère (p=0,000 et p=0,001). La radiographie thoracique était majoritairement pathologique (79,7%), faite de lésions diffuses (55,8%), de type miliaire (21,6%) et cavernes (18,9%), respectivement liées à l’immunodépression sévère (p=0,024 et p=0,000). Conclusion : l’immunodépression constitue un facteur modifiant les aspects radiologiques habituels de la tuberculose pulmonaire. Un aspect normal de la radiographie thoracique chez l’immunodéprimé n’exclut pas la tuberculose pulmonaire évolutive. Le pronostic vital des co-infectés TB/VIH est corrélé au degré d’immunodépression
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Zuo, Mingcheng, e Guangming Dai. "P-lsGOF: A parallel learning-selection-based global optimization framework". Journal of Intelligent & Fuzzy Systems 39, n. 5 (19 novembre 2020): 7333–61. http://dx.doi.org/10.3233/jifs-200753.
Abstract (sommario):
When optimizing complicated engineering design problems, the search spaces are usually extremely nonlinear, leading to the great difficulty of finding optima. To deal with this challenge, this paper introduces a parallel learning-selection-based global optimization framework (P-lsGOF), which can divide the global search space to numbers of sub-spaces along the variables learned from the principal component analysis. The core search algorithm, named memory-based adaptive differential evolution algorithm (MADE), is parallel implemented in all sub-spaces. MADE is an adaptive differential evolution algorithm with the selective memory supplement and shielding of successful control parameters. The efficiency of MADE on CEC2017 unconstrained problems and CEC2011 real-world problems is illustrated by comparing with recently published state-of-the-art variants of success-history based adaptative differential evolution algorithm with linear population size reduction (L-SHADE) The performance of P-lsGOF on CEC2011 problems shows that the optimized results by individually conducting MADE can be further improved.
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Farber, Eduard, Alexey V. Orlov e Anatoly A. Popovich. "TiNi Alloy Lattice Structures with Negative Poisson Ratio: Computer Simulation". Key Engineering Materials 944 (10 aprile 2023): 61–67. http://dx.doi.org/10.4028/p-ek41j4.
Abstract (sommario):
Today, one of the problems of modern implants is their high rigidity, which can lead to bone resorption at the interface between the implant and the bone and to the gradual detachment of the implant. In addition, implant detachment can occur due to the positive Poisson's ratio of the implant along its entire length. This phenomenon is described in detail in [1]. As a possible solution to these problems, it is proposed to use lattice structures with negative Poisson's ratio from TiNi alloy. This alloy has a fairly low modulus of elasticity - about 48 GPa. The use of a porous (lattice) structure of an implant made of TiNi alloy will reduce the modulus of elasticity and bring it closer to the modulus of human cortical bone – 12-17 GPa [2], and possibly the modulus of elasticity of cancellous bone – 0.1-5 GPа [3]. In this work, a computer numerical simulation of strut based lattice structures with several variants of unit cell topology with a negative Poisson's ratio is carried out. For the obtained structures, the following characteristics were calculated - elastic modulus (Young's modulus), modulus of elasticity in shear, Poisson's ratio. The modeling process is implemented using the ANSYS 2019 R2 SpaceClaim finite element analysis package. The data obtained confirmed the promising possibility of modeling and fabricating lattice structures with a low elastic modulus and negative Poisson's ratio from a TiNi alloy. Also, on the basis of this data, conclusions about the influence of the topology and porosity of unit cells on the resulting characteristics of the lattice structure were made.
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Mané, M., AS Koné, L. Guèye, S. Huchard, A. Ayémou, A. Dem, MM Dieng e PM Gaye. "C105: Problématique des cancers du col utérin au Sénégal : Etude de cohorte rétrospective". African Journal of Oncology 2, n. 1 Supplement (1 marzo 2022): S44. http://dx.doi.org/10.54266/ajo.2.1s.c105.ogup1006.
Abstract (sommario):
INTRODUCTION : Le cancer du col utérin est le 4ème cancer de la femme dans le monde, et le 2ème en Afrique, aussi bien en termes d’incidence que de mortalité. Son diagnostic est souvent réalisé dans nos contrées à un stade localement avancé, rendant la radio-chimiothérapie concomitante (RCC) indispensable. Toutefois, l’accès à la radiothérapie (RT) reste encore très limité, imposant la mise en route d’une chimiothérapie dite d’attente, dont le but principal serait de ralentir la progression locale de la maladie et d’éviter une probable dissémination micro-métastatique. L’objectif était d’évaluer l’impact de notre pratique clinique quotidienne sur la réponse tumorale, la toxicité, la qualité de vie, la compliance au traitement et les taux de survie. MATERIELS ET METHODES : Nous avons mené une étude de cohorte rétrospective incluant des patientes prises en charge pour un carcinome épidermoïde du col utérin en 2019 au Service de RT du Centre Hospitalier National Dalal Jamm. RESULTATS : Les 49 patientes, d’âge médian de 56 ans, avaient une maladie localement avancée dans 80%. Une chimiothérapie d’attente a été réalisée dans 53%, avec le doublet carboplatine et paclitaxel dans 81%. La réponse thérapeutique était objective chez 68% des patientes. Le délai médian entre le diagnostic et le début de la RT était de cinq mois. Une RCC a été réalisée chez 45 patientes. L’étalement médian de la RT était de 55 jours. Seule une toxicité de grade ≤2 a été retrouvée et elle était essentiellement digestive (45%), cutanée (18%) et urinaire (10%). Le taux de SSP à deux ans dans le groupe chimiothérapie d’attente était de 87% versus 81% dans le groupe RCC seule avec une p-value de 0,55. CONCLUSION : L’accès à une prise en charge optimale dans les délais constitue un problème. La chimiothérapie d’attente en permettant d’obtenir une réponse tumorale objective sans engendrer une toxicité majeure ni altérer la compliance à la RCC, pourrait gagner une place dans l’arsenal thérapeutique dans les PVD, ou l’accès dans les délais à la RT constitue un véritable problème.
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Yahimi, A., N. Djellata, C. Hanzen e Rachid Kaidi. "Analyse des pratiques de détection des chaleurs dans les élevages bovins laitiers algériens". Revue d’élevage et de médecine vétérinaire des pays tropicaux 66, n. 1 (1 gennaio 2013): 31. http://dx.doi.org/10.19182/remvt.10147.
Abstract (sommario):
Une enquête sur les pratiques de détection des chaleurs a été réalisée dans 222 exploitations bovines, réparties dans cinq régions (wilayas) du centre de l’Algérie (Tizi Ouzou, Blida, Médéa, Tipaza et Bouira). Le questionnaire utilisé contenait des informations générales relatives à l’élevage (nombre de femelles, stabulation, spécialisation) mais aussi les pratiques de détection des chaleurs (périodes d’observation, signes observés) et les moyens complémentaires éventuellement utilisés. La majorité des éleveurs (57 p. 100) ont été confrontés à un problème de détection des chaleurs. Dans 49 p. 100 des cas seulement, ils inséminaient pour la première fois leurs vaches 50 à 90 jours après le vêlage. Un éleveur sur deux (53 p. 100) détectait les chaleurs deux fois par jour et 40 p. 100 les observaient trois fois par jour, cette activité étant pratiquée de manière aléatoire. Ils basaient prioritairement leur constat d’oestrus sur la présence d’un écoulement vulvaire (19 p. 100) ou sur l’acceptation du chevauchement (16 p. 100). La taille du troupeau ou la spécialisation ont été sans influence sur la fréquence des signes considérés. Les vaches n’ayant pas présenté des signes de chaleurs au cours des 60 premiers jours suivant le vêlage ont fait l’objet d’un examen clinique par un vétérinaire dans 76 p. 100 des élevages. Les moyens complémentaires de détection tels que le calendrier rotatif, ou le crayon détecteur n’ont été utilisés que par 34 p. 100 des éleveurs. Les facteurs responsables de la manifestation des chaleurs, les moments et le nombre d’observations, l’examen des anoestrus post-partum et l’utilisation des moyens complémentaires ont été influencés par la spécialisation et la taille de l’élevage, contrairement aux signes des chaleurs, la période d’attente et la difficulté de détection.
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Prata, Bruno de Athayde. "Um algoritmo enxame de partículas para uma variante do problema de máxima cobertura". Revista Gestão da Produção Operações e Sistemas, n. 2 (16 marzo 2012): 189. http://dx.doi.org/10.15675/gepros.v0i2.417.
Abstract (sommario):
O presente trabalho tem por objetivo, reportar o desenvolvimento de uma heurística enxame de partículas binária, para uma variante do problema de máxima cobertura. Tal variante consiste em um problema de minimização, o qual se aproxima bastante do problema p-medianas. Foram geradas aleatoriamente 10 instâncias de médio porte, as quais foram solucionadas de forma exata. Um algoritmo PSO binário foi desenvolvido para a variante supracitada, o qual teve sua performance comparada com o método exato e com uma adaptação da heurística de Chvátal. Os resultados obtidos apontam para a efetividade da abordagem proposta, para os conjuntos de problemas ana-lisados.Palavras-chave: Meta-heurísticas; Otimização Combinatória; Enxame de Partículas Binário.
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Gazdag, Zsolt, e Gábor Kolonits. "A new method to simulate restricted variants of polarizationless P systems with active membranes". Journal of Membrane Computing 1, n. 4 (dicembre 2019): 251–61. http://dx.doi.org/10.1007/s41965-019-00024-z.
Abstract (sommario):
AbstractAccording to the P conjecture by Gh. Păun, polarizationless P systems with active membranes cannot solve $${\mathbf {NP}}$$NP-complete problems in polynomial time. The conjecture is proved only in special cases yet. In this paper we consider the case where only elementary membrane division and dissolution rules are used and the initial membrane structure consists of one elementary membrane besides the skin membrane. We give a new approach based on the concept of object division polynomials introduced in this paper to simulate certain computations of these P systems. Moreover, we show how to compute efficiently the result of these computations using these polynomials.
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Kim, Ju Myung, e Bentuo Zheng. "History, Developments and Open Problems on Approximation Properties". Mathematics 8, n. 7 (7 luglio 2020): 1117. http://dx.doi.org/10.3390/math8071117.
Abstract (sommario):
In this paper, we give a comprehensive review of the classical approximation property. Then, we present some important results on modern variants, such as the weak bounded approximation property, the strong approximation property and p-approximation property. Most recent progress on E-approximation property and open problems are discussed at the end.
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Sangho, O., S. Ouattara, N. Telly, Y. Ballayira, CA Coulibaly, B. Traoré e Et Al. "Evaluation de la prise en charge des patients atteints de tuberculose pulmonaire pharmaco-sensible au Centre de santé de référence, Commune V de Bamako, 2015-2018". Revue Malienne d'Infectiologie et de Microbiologie 16, n. 2 (2 giugno 2021): 26–31. http://dx.doi.org/10.53597/remim.v16i2.1866.
Abstract (sommario):
Introduction : En 2018, 6605 cas de tuberculose ont été notifiés au Mali. Bamako en a notifié 32%. Malgré les efforts déployés, la tuberculose constitue un problème majeur de santé de publique. Objectif : Evaluer la prise en charge de la tuberculose pulmonaire en Commune V de Bamako de 2015 à 2018. Matériel et méthodes : Nous avons réalisé une étude transversale de septembre à octobre 2019 sur des séries de cas de tuberculose pulmonaire enregistrées au Centre de Santé de Référence (CSRéf) de la Commune V de Bamako. A l’analyse bivariée les OR ont été estimés et testées à l’aide du Khi Deux au seuil de signification de 5%. Résultats : Un total de 1221 cas a été analysé. La moyenne d’âge était de 37ans±17ans chez les hommes et 35ans±15ans chez les femmes. Les nouveaux cas étaient représentés avec 88,25%, 92,09%, 82,86% et 86,50% respectivement en 2015, 2016, 2017 et 2018. Les cas de rechute étaient de 4,88% en 2017 et 6,34% en 2015. La co-infection avec le VIH variait entre 12,38% et 15,11%. L’analyse des crachats était le plus fréquent examen réalisé avec des proportions de 76,36% à 91%. L’analyse de 5ème mois a montré une amélioration significative pour 2015 et 2016 (p<0,0005) comparée à celle de 2ème mois. La proportion de patients guéris était de 53,97%, 46,40%, 57,86% et 56,90% respectivement en 2015, 2016, 2017, et 2018. Conclusion : Des résultats encourageants ont été obtenus malgré des taux de guérison en deçà de l’objectif.
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Dabrowski, Konrad K., Carl Feghali, Matthew Johnson, Giacomo Paesani, Daniël Paulusma e Paweł Rzążewski. "On Cycle Transversals and Their Connected Variants in the Absence of a Small Linear Forest". Algorithmica 82, n. 10 (29 aprile 2020): 2841–66. http://dx.doi.org/10.1007/s00453-020-00706-6.
Abstract (sommario):
Abstract A graph is H-free if it contains no induced subgraph isomorphic to H. We prove new complexity results for the two classical cycle transversal problems Feedback Vertex Set and Odd Cycle Transversal by showing that they can be solved in polynomial time on $$(sP_1+ P_3)$$ ( s P 1 + P 3 ) -free graphs for every integer $$s\ge 1$$ s ≥ 1 . We show the same result for the variants Connected Feedback Vertex Set and Connected Odd Cycle Transversal. We also prove that the latter two problems are polynomial-time solvable on cographs; this was already known for Feedback Vertex Set and Odd Cycle Transversal. We complement these results by proving that Odd Cycle Transversal and Connected Odd Cycle Transversal are -complete on $$(P_2+ P_5,P_6)$$ ( P 2 + P 5 , P 6 ) -free graphs.
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Lauri, Juho, e Sourav Dutta. "Fine-Grained Search Space Classification for Hard Enumeration Variants of Subset Problems". Proceedings of the AAAI Conference on Artificial Intelligence 33 (17 luglio 2019): 2314–21. http://dx.doi.org/10.1609/aaai.v33i01.33012314.
Abstract (sommario):
We propose a simple, powerful, and flexible machine learning framework for (i) reducing the search space of computationally difficult enumeration variants of subset problems and (ii) augmenting existing state-of-the-art solvers with informative cues arising from the input distribution. We instantiate our framework for the problem of listing all maximum cliques in a graph, a central problem in network analysis, data mining, and computational biology. We demonstrate the practicality of our approach on real-world networks with millions of vertices and edges by not only retaining all optimal solutions, but also aggressively pruning the input instance size resulting in several fold speedups of state-of-the-art algorithms. Finally, we explore the limits of scalability and robustness of our proposed framework, suggesting that supervised learning is viable for tackling NP-hard problems in practice.
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PĂUN, GHEORGHE. "COMPUTING WITH MEMBRANES (P SYSTEMS): A VARIANT". International Journal of Foundations of Computer Science 11, n. 01 (marzo 2000): 167–81. http://dx.doi.org/10.1142/s0129054100000090.
Abstract (sommario):
Membrane Computing is a recently introduced area of Molecular Computing, where a computation takes place in a membrane structure where multisets of objects evolve according to given rules (they can also pass through membranes). The obtained computing models were called P systems. In basic variants of P systems, the use of objects evolution rules is regulated by a given priority relation; moreover, each membrane has a label and one can send objects to precise membranes, identified by their labels. We propose here a variant where we get rid of both there rather artificial (non-biochemical) features. Instead, we add to membranes and to objects an "electrical charge" and the objects are passed through membranes according to their charge. We prove that such systems are able to characterize the one-letter recursively enumerable languages (equivalently, the recursively enumerable sets of natural numbers), providing that an extra feature is considered: the membranes can be made thicker or thinner (also dissolved) and the communication through a membrane is possible only when its thickness is equal to 1. Several open problems are formulated.
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Wojtas, Krzysztof, e Piotr Faliszewski. "Possible Winners in Noisy Elections". Proceedings of the AAAI Conference on Artificial Intelligence 26, n. 1 (20 settembre 2021): 1499–505. http://dx.doi.org/10.1609/aaai.v26i1.8255.
Abstract (sommario):
We consider the problem of predicting winners in elections given complete knowledge about all possible candidates, all possible voters (together with their preferences), but in the case where it is uncertain either which candidates exactly register for the election or which voters cast their votes. Under reasonable assumptions our problems reduce to counting variants of election control problems. We either give polynomial-time algorithms or prove #P-completeness results for counting variants of control by adding/deleting candidates/voters for Plurality, k-Approval, Approval, Condorcet, and Maximin voting rules.
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Darvay, Zsolt, e Attila-Szabolcs Orbán. "Implementation of the Full-Newton Step Algorithm for Weighted Linear Complementarity Problems". Műszaki Tudományos Közlemények 15, n. 1 (1 ottobre 2021): 15–18. http://dx.doi.org/10.33894/mtk-2021.15.04.
Abstract (sommario):
Abstract We present a path-following interior-point algorithm for solving the weighted linear complementarity problem from the implementation point of view. We studied two variants, which differ only in the method of updating the parameter which characterizes the central path. The implementation was done in the C++ programming language and the obtained numerical results prove the efficiency of the proposed method.
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Arya, Akschat, Boominathan Perumal e Santhi Krishnan. "Parallelized solution to the asymmetric travelling salesman problem using central processing unit acceleration". Indonesian Journal of Electrical Engineering and Computer Science 25, n. 3 (1 marzo 2022): 1795. http://dx.doi.org/10.11591/ijeecs.v25.i3.pp1795-1802.
Abstract (sommario):
<p><span>Travelling salesman problem is a well researched problem in computer science and has many practical applications. It is classified as a NP-hard problem as its exact solution can only be obtained in exponential time unless P = NP. There are different variants of the travelling salesman problem (TSP) and in this paper, asymmetric travelling salesman problem is addressed since this variant is quite often observed in real world scenarios. There are a number of heuristic approaches to this problem which provides approximate solutions in polynomial time, however this paper proposes an exact optimal solution which is accelerated with the help of multi-threading-based parallelization. In order to find the exact optimal solution, we have used the held-karp algorithm involving dynamic programming and to reduce the time taken to find the optimal path, we have used a multi-threaded approach to parallelize the processing of sub-problems by leveraging the central processing unit cores (CPUs). This method is an extension of a well researched solution to the TSP; however, this method shows that solutions to computationally intensive problems involving sub-problems such as the asymmetic travelling salesman problem (ATSP) can be accelerated with the help of modern CPUs.</span></p>
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Lu, Chun, e Xingyi Zhang. "Solving Vertex Cover Problem by Means of Tissue P Systems with Cell Separation". International Journal of Computers Communications & Control 5, n. 4 (1 novembre 2010): 540. http://dx.doi.org/10.15837/ijccc.2010.4.2512.
Abstract (sommario):
Tissue P systems is a computing model in the framework of membrane computing inspired from intercellular communication and cooperation between neurons. Many different variants of this model have been proposed. One of the most important models is known as tissue P systems with cell separation. This model has the ability of generating an exponential amount of workspace in linear time, thus it allows us to design cellular solutions to NP-complete problems in polynomial time. In this paper, we present a solution to the Vertex Cover problem via a family of such devices. This is the first solution to this problem in the framework of tissue P systems with cell separation.
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Ivanova, V. A., e L. A. Ulianitckaia. "Pluricentric Languages Policy Features through the Example of French". Discourse 6, n. 5 (30 novembre 2020): 113–29. http://dx.doi.org/10.32603/2412-8562-2020-6-5-113-129.
Abstract (sommario):
Introduction. The paper reviews features of the French language policy inFrance,Belguim,Canada, andSwitzerland. The novelty of the study is implied by the fact that features of the language policy are analyzed with previously unknown circumstances taken into account: the circumstances that allow French to be seen as a pluricentric language. The relevance of the study is conditioned by the necessity of observing the sociopolitical space of language functioning, as well as the importance of both analyzing the dynamics of pluricentric languages spreading and identifying mechanisms of using a single language for either uniting disparate nations or countries manipulating.Methodology and sources. The method of the study is a comprehensive approach with a number of linguistic and social variables correlations. The study was conducted using official websites of Organisation international dela Francophonie describing official bodies and institutions responsible for language policy implementation, as well as articles of various publications (Le soir, The Guardian, Ethnologies), devoted to the discussion of French norm regulation problems as the material of the study.Results and discussion. The main result of the study is a review of the status of French as a pluricentric language worldwide, particularly in countries considered to be centres of French variants development and having French as an official language. Main features of a pluricentric language, as well as the factors that turn a monocentric language into a pluricentric one (through the example of French) are looked at. The actions taken by the Organisation internationale dela Francophonie and aimed at the strengthening of relations between French-speaking countries and the promoting of the French language worldwide are described. The study also illustrates the dependence of peripheral language centres fromFrance. An emphasis is put on the politics of the Académie Française aimed at the French language unification in all the countries having it as an official language. An assumption on the reasons of different deviation extent of French variants inCanada,Belgium, andSwitzerland from Standard French is made.Conclusion. It is impossible to consider language to be an independent and isolated phenomenon as it exists and evolves within society serving its needs. Institutions pursuing a language policy are in position to affect its development directly, yet in the context of pluricentric languages it is insufficient to have a single centre of linguistic regulation. Local institutions may have a policy that runs contrary to the language policy of the centre. Gender reforms can also become a new wave of linguistic changes leading to further distancing of different language variants.
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Benghezel, Hichem, Asma Cheribet, Hadjer Bezzouza, Imene Khelifi, Nedjoua Alloui, Rafik Bencherif e Hanane Boukrous. "Hyperuricemia and cardiovascular risk: study in a population admitted to the cardiology department of the University Hospital of Batna". Batna Journal of Medical Sciences (BJMS) 6, n. 2 (30 dicembre 2019): 109–15. http://dx.doi.org/10.48087/bjmsoa.2019.6206.
Abstract (sommario):
La pathologie coronarienne est une pathologie grave posant un véritable problème de santé publique. De nombreux facteurs de risques sont à l’origine ou aggravent cette affection. L’incrimination de l’hyperuricémie comme facteur du risque cardiovasculaire reste un sujet discuté. Nous avons réalisé une étude rétrospective sur 95 prélèvements de patients collectés au niveau du service de cardiologie du centre hospitalo-universitaire de Batna Algérie, afin d’évaluer l’importance et les associations possibles entre l’hyperuricémie et les autres facteurs du risque cardiovasculaire à savoir : diabète, hypertension artérielle, insuffisance rénale, obésité, tabagisme, dyslipidémie, et son rôle directe ou non dans le syndrome coronarien aigu. L’automate cobas e411 roche diagnostics® est utilisé pour le dosage de la Troponine T ultrasensible et l'automate cobas 6000 module c501 roche diagnostics® pour le dosage de l’acide urique, du cholestérol total, du HDL direct, des triglycérides, de l’urée, de la créatinine, de l’Apo A, de l’Apo B100, de la protéine C réactive ultrasensible et l’homocystéine. L’estimation du LDL est effectuée par la formule de Friedewald. Nous avons également calculé le risque relatif cardiovasculaire (RR) par la formule de QRISK®2-2017. Nous avons estimé le débit de filtration glomérulaire selon la formule Modification of Diet in Renal Disease (MDRD) Study equation. L'analyse statistique des donnés est réalisée le logiciel SPSS statistic version 20 (test de Kruskal-Wallis, test d’indépendance du Chi-deux et Phi). Les valeurs de p inférieures à 0,05 ont été considérées comme statistiquement significatives. L’effet causal direct de l'hyperuricémie dans les maladies cardiovasculaires n’a pas pu être tranché. Néanmoins, il semble que l’hyperuricémie est fortement associée aux maladies cardiovasculaires chez la population féminine. Des associations entre l’hyperuricémie et l’élévation de la protéine C reactive (p= 0,063) (Chi-deux : 3,49, p=0,194, Phi=0,174) et la baisse de l’apo B (p=0,008) (Chi-deux : 6,23, p=0,044, Phi=0,256) confortent l’idée des effets pro inflammatoires de l’acide urique et soulèvent la question de la possibilité que des concentrations réduites de l'apo B100 soit un facteur favorisant l’hyperuricémie.
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Holling, Tess, Sheela Nampoothiri, Bedirhan Tarhan, Pauline E. Schneeberger, Kollencheri Puthenveettil Vinayan, Dhanya Yesodharan, Arun Grace Roy et al. "Novel biallelic variants expand the SLC5A6-related phenotypic spectrum". European Journal of Human Genetics 30, n. 4 (11 gennaio 2022): 439–49. http://dx.doi.org/10.1038/s41431-021-01033-2.
Abstract (sommario):
AbstractThe sodium (Na+):multivitamin transporter (SMVT), encoded by SLC5A6, belongs to the sodium:solute symporter family and is required for the Na+-dependent uptake of biotin (vitamin B7), pantothenic acid (vitamin B5), the vitamin-like substance α-lipoic acid, and iodide. Compound heterozygous SLC5A6 variants have been reported in individuals with variable multisystemic disorder, including failure to thrive, developmental delay, seizures, cerebral palsy, brain atrophy, gastrointestinal problems, immunodeficiency, and/or osteopenia. We expand the phenotypic spectrum associated with biallelic SLC5A6 variants affecting function by reporting five individuals from three families with motor neuropathies. We identified the homozygous variant c.1285 A > G [p.(Ser429Gly)] in three affected siblings and a simplex patient and the maternally inherited c.280 C > T [p.(Arg94*)] variant and the paternally inherited c.485 A > G [p.(Tyr162Cys)] variant in the simplex patient of the third family. Both missense variants were predicted to affect function by in silico tools. 3D homology modeling of the human SMVT revealed 13 transmembrane helices (TMs) and Tyr162 and Ser429 to be located at the cytoplasmic facing region of TM4 and within TM11, respectively. The SLC5A6 missense variants p.(Tyr162Cys) and p.(Ser429Gly) did not affect plasma membrane localization of the ectopically expressed multivitamin transporter suggesting reduced but not abolished function, such as lower catalytic activity. Targeted therapeutic intervention yielded clinical improvement in four of the five patients. Early molecular diagnosis by exome sequencing is essential for timely replacement therapy in affected individuals.
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Alfano, Gaetano, Francesco Fontana, Niccolò Morisi, Giacomo Mori, Gianni Cappelli, Riccardo Magistroni e Gabriele Donati. "Ethical challenges in managing unvaccinated patients receiving chronic in-centre haemodialysis". Clinical Kidney Journal 15, n. 4 (16 dicembre 2021): 615–17. http://dx.doi.org/10.1093/ckj/sfab276.
Abstract (sommario):
ABSTRACT Insufficient vaccine coverage and dominance of the more transmissible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are the leading causes of the continued spread of coronavirus disease 2019 (COVID-19) worldwide. To curb the surge in infections, COVID-19 vaccination has been advocated as a priority measure, especially for frail populations and people at high risk of exposure. Patients on in-centre maintenance haemodialysis (HD) embody both conditions. They are at high risk of severe COVID-19 consequences due to their advanced age and weakened immune system and carry an increased risk of SARS-CoV-2 transmission within shared dialysis rooms and public vehicles. Vaccination of the entire HD population is therefore the most effective strategy to protect patients from the dire consequences of COVID-19. Unfortunately, a minority of patients still express COVID-19 vaccine hesitancy. The management of this group of patients, who have the full right to HD treatment, poses demanding problems from a patient safety perspective. The placement of unvaccinated patients within the dialysis room and the protection of all vaccinated patients are some of the most urgent problems the nephrologist faces during the COVID-19 pandemic. In light of these COVID-19-driven changes, an ethical reflection on the management of unvaccinated patients appears crucial to act responsibly and contribute to the health promotion of dialysis patients.
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Ul Hassan, Nafees, Waqas Haider Bangyal, M. Sadiq Ali Khan, Kashif Nisar, Ag Asri Ag. Ibrahim e Danda B. Rawat. "Improved Opposition-Based Particle Swarm Optimization Algorithm for Global Optimization". Symmetry 13, n. 12 (1 dicembre 2021): 2280. http://dx.doi.org/10.3390/sym13122280.
Abstract (sommario):
Particle Swarm Optimization (PSO) has been widely used to solve various types of optimization problems. An efficient algorithm must have symmetry of information between participating entities. Enhancing algorithm efficiency relative to the symmetric concept is a critical challenge in the field of information security. PSO also becomes trapped into local optima similarly to other nature-inspired algorithms. The literature depicts that in order to solve pre-mature convergence for PSO algorithms, researchers have adopted various parameters such as population initialization and inertia weight that can provide excellent results with respect to real world problems. This study proposed two newly improved variants of PSO termed Threefry with opposition-based PSO ranked inertia weight (ORIW-PSO-TF) and Philox with opposition-based PSO ranked inertia weight (ORIW-PSO-P) (ORIW-PSO-P). In the proposed variants, we incorporated three novel modifications: (1) pseudo-random sequence Threefry and Philox utilization for the initialization of population; (2) increased population diversity opposition-based learning is used; and (3) a novel introduction of opposition-based rank-based inertia weight to amplify the execution of standard PSO for the acceleration of the convergence speed. The proposed variants are examined on sixteen bench mark test functions and compared with conventional approaches. Similarly, statistical tests are also applied on the simulation results in order to obtain an accurate level of significance. Both proposed variants show highest performance on the stated benchmark functions over the standard approaches. In addition to this, the proposed variants ORIW-PSO-P and ORIW-PSO-P have been examined with respect to training of the artificial neural network (ANN). We have performed experiments using fifteen benchmark datasets obtained and applied from the repository of UCI. Simulation results have shown that the training of an ANN with ORIW-PSO-P and ORIW-PSO-P algorithms provides the best results than compared to traditional methodologies. All the observations from our simulations conclude that the proposed ASOA is superior to conventional optimizers. In addition, the results of our study predict how the proposed opposition-based method profoundly impacts diversity and convergence.
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Zhang, Xue Bai, Ge Xiang Zhang e Ji Xiang Cheng. "An Improved Quantum-Inspired Evolutionary Algorithm Based on P Systems with a Dynamic Membrane Structure for Knapsack Problems". Applied Mechanics and Materials 239-240 (dicembre 2012): 1528–31. http://dx.doi.org/10.4028/www.scientific.net/amm.239-240.1528.
Abstract (sommario):
To improve the performance of Quantum-inspired Evolutionary algorithm based on P Systems (QEPS), this paper presents an improved QEPS with a Dynamic Membrane Structure (QEPS-DMS) to solve knapsack problems. QEPS-DMS combines quantum-inspired evolutionary algorithms (QIEAs) with a P system with a dynamic membrane structure. In QEPS-DMS, a QIEA is considered as a subalgorithm to put inside each elementary membrane of a one-level membrane structure, which is dynamically adjusted in the process of evolution by applying a criterion for measuring population diversity. The dynamic adjustment includes the processes of membrane dissolution and creation. Knapsack problems are applied to test the effectiveness of QEPS-DMS. Experimental results show that QEPS-DMS outperforms QEPS and three variants of QIEAs recently reported in the literature.
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BAREQUET, GILL, e SARIEL HAR-PELED. "POLYGON CONTAINMENT AND TRANSLATIONAL IN-HAUSDORFF-DISTANCE BETWEEN SEGMENT SETS ARE 3SUM-HARD". International Journal of Computational Geometry & Applications 11, n. 04 (agosto 2001): 465–74. http://dx.doi.org/10.1142/s0218195901000596.
Abstract (sommario):
The 3SUM problem represents a class of problems conjectured to require Ω(n2) time to solve, where n is the size of the input. Given two polygons P and Q in the plane, we show that some variants of the decision problem, whether there exists a transformation of P that makes it contained in Q, are 3SUM-hard. In the first variant P and Q are any simple polygons and the allowed transformations are translations only; in the second and third variants both polygons are convex and we allow either rotations only or any rigid motion. We also show that finding the translation in the plane that minimizes the Hausdorff distance between two segment sets is 3SUM-hard.
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Richard Owusu Nyarko, R. Roopini, Velicharla Raviteja, Chinaza Godswill Awuchi, Roshan Kumar, Erwin Martinez Faller, Elrey Librea Navarro et al. "Novel Sars-CoV-2 Variants & Therapeutic Effects". Journal for Research in Applied Sciences and Biotechnology 1, n. 2 (30 giugno 2022): 25–34. http://dx.doi.org/10.55544/jrasb.1.2.3.
Abstract (sommario):
COVID-19 is a severe respiratory infection caused by coronavirus 2. (SARS-CoV-2). Even while SARS-CoV-2 predominantly affects the respiratory system, it can cause problems for other important organs as well. Multiple novel variations of concern have appeared since the beginning of the SARS-CoV-2 pandemic, including the Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), and Omicron (B.1.1.529), all of which are linked to increased transmissibility and severity. Both the newly discovered variants and the most recent innovative treatments for the treatment of COVID-19 are discussed in this work. Care for people with this disease is discussed, with an emphasis on the need of clinical interprofessional teams, government health organisations, and community involvement.
36
Kalenchuk, M. L., e D. M. Savinov. "Problems and prospects of educational lexicography: a new school dictionary of Russian pronunciation". Russian language at school 85, n. 1 (17 gennaio 2024): 67–77. http://dx.doi.org/10.30515/0131-6141-2024-85-1-67-77.
Abstract (sommario):
The article critically examines various educational pronouncing (orthoepic) dictionaries and states the main objections to the quality of such resources. Criticism centres on the irregularities in the transcription rules adopted in school textbooks; phonetic and orthoepic errors; mixing orthoepic information with other linguistic phenomena; the issue of age-related adaptation of school dictionaries; insufficient relevance of pronunciation instructions; criteria for glossary compilation. The analysis demonstrated the need for creating a new educational dictionary, a Dictionary of Russian Pronunciation Difficulties, for years 5 to 11. It was compiled at the V. V. Vinogradov Russian Language Institute of the Russian Academy of Sciences under the editorship of M. L. Kalenchuk and D. M. Savinov. The cornerstone of this lexicographic source is the idea that normative recommendations in dictionaries should be based on the actual speech practices of educated people. The article justifies the choice of the pronouncing dictionary type and argues for a dictionary of difficulties rather than an orthoepic dictionary proper. We provide comprehensive criteria for compiling a dictionary glossary and structuring a dictionary entry. The paper also formulates the principles of normative evaluation of stress and pronunciation of sounds used in codification, as well as the system of permissive and prohibitive standard notes. If necessary, the Dictionary entries provide additional orthoepic data about obsolete pronunciation variants, folk poetic and professional accentual features, stress variants and pronunciation of sounds specific to phraseological units. Information about obsolete variants found in fiction is illustrated and verified with examples from poetic texts.
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Udaya Kumar Reddy, K. R. "A survey of the all-pairs shortest paths problem and its variants in graphs". Acta Universitatis Sapientiae, Informatica 8, n. 1 (1 giugno 2016): 16–40. http://dx.doi.org/10.1515/ausi-2016-0002.
Abstract (sommario):
Abstract There has been a great deal of interest in the computation of distances and shortest paths problem in graphs which is one of the central, and most studied, problems in (algorithmic) graph theory. In this paper, we survey the exact results of the static version of the all-pairs shortest paths problem and its variants namely, the Wiener index, the average distance, and the minimum average distance spanning tree (MAD tree in short) in graphs (focusing mainly on algorithmic results for such problems). Along the way we also mention some important open issues and further research directions in these areas.
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Ho, Ky, e Inbo Sim. "On sufficient “local” conditions for existence results to generalized p(.)-Laplace equations involving critical growth". Advances in Nonlinear Analysis 12, n. 1 (3 settembre 2022): 182–209. http://dx.doi.org/10.1515/anona-2022-0269.
Abstract (sommario):
Abstract In this article, we study the existence of multiple solutions to a generalized p ( ⋅ ) p\left(\cdot ) -Laplace equation with two parameters involving critical growth. More precisely, we give sufficient “local” conditions, which mean that growths between the main operator and nonlinear term are locally assumed for p ( ⋅ ) p\left(\cdot ) -sublinear, p ( ⋅ ) p\left(\cdot ) -superlinear, and sandwich-type cases. Compared to constant exponent problems (e.g., p p -Laplacian and ( p , q ) \left(p,q) -Laplacian), this characterizes the study of variable exponent problems. We show this by applying variants of the mountain pass theorem for p ( ⋅ ) p\left(\cdot ) -sublinear and p ( ⋅ ) p\left(\cdot ) -superlinear cases and constructing critical values defined by a minimax argument in the genus theory for sandwich-type case. Moreover, we also obtain a nontrivial nonnegative solution for sandwich-type case changing the role of parameters. Our work is a generalization of several existing works in the literature.
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Borsuk, Yurii. "Topological analysis of roadway and railway networks of the Ukrainian-Polish borderlands (on the example of Lviv Oblast and Subcarpathian Voivodeship)". Journal of Geology, Geography and Geoecology 33, n. 1 (24 marzo 2024): 44–53. http://dx.doi.org/10.15421/112405.
Abstract (sommario):
The paper presents an analysis of functioning of roadway and railway networks in the context of logistics flows. The interaction of road vehicles and railroad cars within the given territories was characterized. The provided spatiotemporal modelling allows comparing the configuration of roadways and railways from the peripheral settlements to the regional capitals. The points that form transport links with the administrative centres of each studied territory were identified. A comparative topological analysis of the given lines of roadway and railway transport within the Ukrainian-Polish borderland employed quantitative (distance, time) and qualitative (curvature, travel speed) modelling parameters, characterizing the relationship of the borderland territories in two neighbouring countries of Eastern Europe. Relative indicators, which include curvature and speed, were estimated. A database of settlements based on accessibility to the city by road and rail transport was created, taking into account the top-10 centres of territorial communities, or hromadas, in Lviv Oblast and Subcarpathian Voivodeship. Alternative modes of transport for travelling from a centre of territorial community to the regional centre in Ukraine and Poland were highlighted. The study compared the settlements with low transport accessibility to the regional capital (oblast, voivodeship), taking into account the functioning of the roadway and railway networks. Social-geographical problems of the given territories were identified based on the analysis of topological indicators of each transport connections. I found that the network system of transport infrastructure in Subcarpathian Voivodeship is low-dense, especially in mountainous areas. Also, there was analyzed high accessibility of suburban settlements to the city of Rzeszów. In Lviv, connection between the suburbs and the city centre can be called problematic. Within the studied borderland areas, there were also found cases of disuse of the existing railway stations for passenger traffic. Variants that would promote the development of public transport in the Lviv Oblast have been proposed, based on the example of the transport model in Subcarpathian Voivodeship. Applied developments include the need to build the Opillia-Roztocze highway, assignement of high-speed electric trains from remote areas to the regional capital.
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Song, Bosheng, Kenli Li, David Orellana-Martín, Mario J. Pérez-Jiménez e Ignacio PéRez-Hurtado. "A Survey of Nature-Inspired Computing". ACM Computing Surveys 54, n. 1 (aprile 2021): 1–31. http://dx.doi.org/10.1145/3431234.
Abstract (sommario):
Nature-inspired computing is a type of human-designed computing motivated by nature, which is based on the employ of paradigms, mechanisms, and principles underlying natural systems. In this article, a versatile and vigorous bio-inspired branch of natural computing, named membrane computing is discussed. This computing paradigm is aroused by the internal membrane function and the structure of biological cells. We first introduce some basic concepts and formalisms of membrane computing, and then some basic types or variants of P systems (also named membrane systems ) are presented. The state-of-the-art computability theory and a pioneering computational complexity theory are presented with P system frameworks and numerous solutions to hard computational problems (especially NP -complete problems) via P systems with membrane division are reported. Finally, a number of applications and open problems of P systems are briefly described.
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Oláhová, Monika, Camilla Ceccatelli Berti, Jack J. Collier, Charlotte L. Alston, Elisabeth Jameson, Simon A. Jones, Noel Edwards et al. "Molecular genetic investigations identify new clinical phenotypes associated with BCS1L-related mitochondrial disease". Human Molecular Genetics 28, n. 22 (22 agosto 2019): 3766–76. http://dx.doi.org/10.1093/hmg/ddz202.
Abstract (sommario):
Abstract BCS1L encodes a homolog of the Saccharomyces cerevisiae bcs1 protein, which has a known role in the assembly of Complex III of the mitochondrial respiratory chain. Phenotypes reported in association with pathogenic BCS1L variants include growth retardation, aminoaciduria, cholestasis, iron overload, lactic acidosis and early death (GRACILE syndrome), and Björnstad syndrome, characterized by abnormal flattening and twisting of hair shafts (pili torti) and hearing problems. Here we describe two patients harbouring biallelic variants in BCS1L; the first with a heterozygous variant c.166C>T, p.(Arg56*) together with a novel heterozygous variant c.205C>T, p.(Arg69Cys) and a second patient with a novel homozygous c.325C>T, p.(Arg109Trp) variant. The two patients presented with different phenotypes; the first patient presented as an adult with aminoaciduria, seizures, bilateral sensorineural deafness and learning difficulties. The second patient was an infant who presented with a classical GRACILE syndrome leading to death at 4 months of age. A decrease in BCS1L protein levels was seen in both patients, and biochemical analysis of Complex III revealed normal respiratory chain enzyme activities in the muscle of both patients. A decrease in Complex III assembly was detected in the adult patient’s muscle, whilst the paediatric patient displayed a combined mitochondrial respiratory chain defect in cultured fibroblasts. Yeast complementation studies indicate that the two missense variants, c.205C>T, p.(Arg69Cys) and c.325C>T, p.(Arg109Trp), impair the respiratory capacity of the cell. Together, these data support the pathogenicity of the novel BCS1L variants identified in our patients.
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Paslawski, Jerzy. "FLEXIBILITY APPROACH IN CONSTRUCTION PROCESS ENGINEERING / LANKSTUMAS STATYBOS PROCESO INŽINERIJOJE". Technological and Economic Development of Economy 14, n. 4 (31 dicembre 2008): 518–30. http://dx.doi.org/10.3846/1392-8619.2008.14.518-530.
Abstract (sommario):
The issues of environmental impact on building processes constitute a permanent aspect of the building industry, irrespective of various preventive actions (prefabrication, robotics etc.). The proposed method was developed in the course of tracking problems that arise during performance of building processes exposed to weather impact (as an example of interruptions) on construction sites of airports, highways, logistic centres, or installation of tall building facades. The proposed approach is based on creating multiple variants for process realization options, thus enabling adaptation to current realization conditions at particular stages. The studies that have been carried out confirm the advantage of this method over the traditional planning based on a single realization variant. Santrauka Aplinkos poveikis statybos procesui yra būdingas statybos pramonei nepaisant prevencinių veiksmų (surenkamųjų elementų gamyba, robotizacija). Pasiūlytas metodas buvo sukurtas stebint problemas, atsirandančias vykdant oro sąlygų veikiamus statybos procesus (pavyzdžiui, trikdžius) oro uostų, magistralinių kelių, logistikos centrų, aukštų pastatų fasado įrengimo darbų, statybos aikštelėse. Sukurtojo metodo esmė – pasiūlyti daug variantų konkrečiam procesui įvykdyti. Tai leidžia parinkti tam tikras konkrečių darbų etapų įvykdymo sąlygas. Tyrimas patvirtino, kad šis metodas pranašesnis už tradicinį planavimą, teturintį vienintelį darbų įvykdymo variantą.
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Gumisirizah, Nicholus, Charles M. Muwonge e Joseph Nzabahimana. "Effect of problem-based learning on students’ problem-solving ability to learn physics". Physics Education 59, n. 1 (20 novembre 2023): 015015. http://dx.doi.org/10.1088/1361-6552/ad0577.
Abstract (sommario):
Abstract A learner’s success is supported by the ability to understand real-world problems. This study aimed to examine the effect of problem-based learning on problem-solving ability in the teaching and learning of physics. The study was guided by socio-constructivism theory. A quasi-experiment was conducted with 829 Senior-2 Physics students (age 13–15) from eight (8) selected lower secondary schools in Sheema District, Uganda. Schools were assigned to treatment and control groups using a purposive random sampling technique. Students’ problem-solving ability was measured by conducting a problem-solving ability test in each group before and after studying a chapter on simple machines in physics. Repeated measures analysis of variances was applied for data analysis. The study’s findings showed a significant improvement in students’ problem-solving ability with simple machines in the treatment group compared to the control group (p < .001). Therefore, educators are encouraged to embrace learner-centred methods that enhance students’ problem-solving abilities to help them compete in the world of work.
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Orlova, E. M. "Federal clinical recommendations on diagnostics and treatment of hypoparathyroidism in the children and adolescents". Problems of Endocrinology 60, n. 3 (15 giugno 2014): 69–74. http://dx.doi.org/10.14341/probl201460369-74.
Abstract (sommario):
Hypoparathyroidism is a rare etiologically heterogeneous condition that manifests itself in the children in the first place as hypocalcemia. The purely hypocalcemic convulsions are usually interpreted as manifestations of epilepsy which leads to the prescription of an inadequate treatment. The early diagnostics and correct therapy ensure the normal development and social adaptation of the affected child. The present clinical guidelines developed at the Institute of Pediatric Endocrinology, Endocrinological Research Centre, highlight the diagnostic problems pertaining to hypoparathyroidism, as well as its clinical and genetic variants. In addition, the algorithm of diagnostics of hypocalcemic syndrom is proposed in conjunction with the schemes for its treatment.
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Aguilar-Ordoñez, Israel, Fernando Pérez-Villatoro, Humberto García-Ortiz, Francisco Barajas-Olmos, Judith Ballesteros-Villascán, Ram González-Buenfil, Cristobal Fresno et al. "Whole genome variation in 27 Mexican indigenous populations, demographic and biomedical insights". PLOS ONE 16, n. 4 (8 aprile 2021): e0249773. http://dx.doi.org/10.1371/journal.pone.0249773.
Abstract (sommario):
There has been limited study of Native American whole genome diversity to date, which impairs effective implementation of personalized medicine and a detailed description of its demographic history. Here we report high coverage whole genome sequencing of 76 unrelated individuals, from 27 indigenous groups across Mexico, with more than 97% average Native American ancestry. On average, each individual has 3.26 million Single Nucleotide Variants and short indels, that together comprise a catalog of 9,737,152 variants, 44,118 of which are novel. We report 497 common Single Nucleotide Variants (with allele frequency > 5%) mapped to drug responses and 316,577 in enhancer or promoter elements; interestingly we found some of these enhancer variants in PPARG, a nuclear receptor involved in highly prevalent health problems in Mexican population, such as obesity, diabetes, and insulin resistance. By detecting signals of positive selection we report 24 enriched key pathways under selection, most of them related to immune mechanisms. No missense variants in ACE2, the receptor responsible for the entry of the SARS CoV-2 virus, were found in any individual. Population genomics and phylogenetic analyses demonstrated stratification in a Northern-Central-Southern axis, with major substructure in the Central region. The Seri, a northern group with the most genetic divergence in our study, showed a distinctive genomic context with the most novel variants, and the most population specific genotypes. Genome-wide analysis showed that the average haplotype blocks are longer in Native Mexicans than in other world populations. With this dataset we describe previously undetected population level variation in Native Mexicans, helping to reduce the gap in genomic data representation of such groups.
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Linders, Cathelijne C., Agnies M. van Eeghen, Janneke R. Zinkstok, Marie-José van den Boogaard e Erik Boot. "Intellectual and Behavioral Phenotypes of Smith–Magenis Syndrome: Comparisons between Individuals with a 17p11.2 Deletion and Pathogenic RAI1 Variant". Genes 14, n. 8 (25 luglio 2023): 1514. http://dx.doi.org/10.3390/genes14081514.
Abstract (sommario):
Aim: Smith–Magenis syndrome (SMS) is a rare genetic neurodevelopmental disorder caused by a 17p11.2 deletion or pathogenic variant in the RAI1 gene. SMS is associated with developmental delay, intellectual disability (ID), and major sleep and behavioral disturbances. To explore how genetic variants may affect intellectual functioning and behavior, we compared intellectual and behavioral phenotypes between individuals with a 17p11.2 deletion and pathogenic RAI1 variant. Method: We reviewed available clinical records from individuals (aged 0–45 years) with SMS, ascertained through a Dutch multidisciplinary SMS specialty clinic. Results: We included a total of 66 individuals (n = 47, 71.2% with a 17p11.2 deletion and n = 19, 28.8% with a pathogenic RAI1 variant) for whom data were available on intellectual functioning, severity of ID (n = 53), and behavioral problems assessed with the Child Behavior Checklist (CBCL, n = 39). Median full-scale IQ scores were lower (56.0 vs. 73.5, p = 0.001) and the proportion of individuals with more severe ID was higher (p = 0.01) in the 17p11.2 deletion group. Median total CBCL 6–18 scores (73.5 vs. 66.0, p = 0.02) and scores on the sub-scales somatic complaints (68.0 vs. 57.0, p = 0.001), withdrawn/depressed behavior (69.5 vs. 55.0, p = 0.02), and internalizing behavior (66.0 vs. 55.0, p = 0.002) were higher in the RAI1 group. Conclusion: The results of this study suggest that 17p11.2 deletions are associated with a lower level of intellectual functioning and less internalizing of problems compared to pathogenic RAI1 variants. The findings of this study may contribute to personalized-management strategies in individuals with SMS.
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Arce Gonzáles, Luís Alberto, e Enrique Guadalupe Gómez. "Explotación de mantos de poco espesor, aplicando el método Cámaras y Pilares con Galería Central y Pilares escalonados - Mina Aztlán 2 – Jalisco - México". Revista del Instituto de Investigación de la Facultad de Ingeniería Geológica, Minera, Metalúrgica y Geográfica 23, n. 46 (30 novembre 2020): 29–36. http://dx.doi.org/10.15381/iigeo.v23i46.19179.
Abstract (sommario):
En minería subterránea la explotación de mantos de espesores menores a 1.20 m, se torna difícil y muy a menudo su costo de minado es elevado, esto debido al método de explotación tradicional que se suele emplear. Este trabajo tiene como objetivo plantear un nuevo diseño de explotación y dar solución al problema operativo en la unidad minera de Aztlán 2 en Autlán de Navarro, Jalisco, México, donde el manto tiene un espesor menor de 1.20 m. Para alcanzar el objetivo planteado se diseñó una variante del método cámara y pilares, que se le ha denominado: cámaras y pilares con galería central y pilares escalonados o sencillamente T Room, permitiendo reducir el costo de minado de USS $ 59.00 dólares la tonelada extraída a USS $ 38.00 dólares, además le da mayor velocidad a la explotación y pasar la producción de 200 toneladas /mes en forma artesanal a 3400 Tn/mes, usando esta nueva variante. La aplicación de esta variante muestra que es económicamente viable para estructuras que tengan similares características, es decir tengan cajas competentes y cuyos espesores sean menores a 1.2 m.
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Sychev, A., V. Avilov, M. Savenkova, E. Luneva e A. Sychev. "Improvement of the tribological properties of heavy-loaded friction units “Centre block-footstep bearing” of a freight car". Journal of Physics: Conference Series 2131, n. 5 (1 dicembre 2021): 052033. http://dx.doi.org/10.1088/1742-6596/2131/5/052033.
Abstract (sommario):
Abstract Various problems and different approaches of solution of such a problematic unit as “centre block-footstep bearing” of freight cars are discussed in the paper. The methods of improving the tribological properties of this friction unit by means of material modification of friction surfaces and perfection of physical, chemical and tribological properties of the used lubricants were studied. Grease lubricants common for friction units of railway machinery were used after being modified with inorganic polymers based on double metaphosphates. Bench and operational tests of the developed additive of the polymeric double metaphosphates were carried out. This additive reduces wear and increases the service life of the friction unit, due to the better adhesion properties of this additive. The variants with a change in the geometry of the contact surface of the disk between the bolster and the “centre block-footstep bearing” arrangement of the car are considered. Simulation of the parameters of movement in curved sections is proposed.
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Montero Delgado, Juan. "Variantes de autor en un poema de Fernando de Herrera: Elegía a la muerte de don Pedro de Zúñiga". Creneida. Anuario de Literaturas Hispánicas, n. 10 (22 gennaio 2023): 149–92. http://dx.doi.org/10.21071/calh.vi10.15051.
Abstract (sommario):
Estudiamos en este trabajo un caso dentro del complejo problema textual herreriano, el de la elegía a la muerte de don Pedro de Zúñiga, fallecido seguramente h. 1570-1571. Del poema nos han llegado dos testimonios íntegros, uno en un manuscrito de 1578 y otro impreso en la edición póstuma de los Versos de Herrera por Francisco Pacheco (1619), además del testimonio parcial (tres versos), pero muy útil, que se recoge en las Anotaciones a Garcilaso (1580). El análisis de las variantes demuestra que la versión P es el resultado de una intensa y coherente reescritura del poema, marcada por la intensificación cultista. Esto nos lleva a concluir que su autor es el propio Herrera, en algún momento entre 1582 (Algunas obras) y 1597 (fecha de su muerte). Resulta verosímil que P represente la redacción final del texto, pero no puede demostrarse.
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Xiaoxiao, Lyu. "Problems in the Translation of Phraseologisms in Bilingual Dictionaries Spanish-Chinese / Chinese-Spanish". Sinología hispánica 1, n. 8 (15 giugno 2019): 103. http://dx.doi.org/10.18002/sin.v1i8.5928.
Abstract (sommario):
<p>The phraseology is part of the linguistic studies on phrases, proverbs, idioms, proverbs and other units of syntax totally or partially fixed. It is the reflection of a certain tradition and idiosyncrasy of society. The native speaker recognizes the phraseological units in the praxis of speech without difficulty. However, because of their idiomaticity and the sociocultural divergence between two linguistic communities, Spanish sayings and expressions cannot always be understood by the Chinese speakers. Students of Spanish as a foreign language have difficulty recognizing the non-literal meaning of an expression, the use of this type of expression in language teaching develops communicative competence, linguistics competence, sociolinguistics and pragmatics competence. Then, when producing a bilingual dictionary, it is not enough to translate it into the target language, but rather to contrast the two languages in order to inform non-native speakers of unknown elements, such as historical and cultural backgrounds, uses, and their frequency of application, variants, etc.</p>