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排序方式: 共有892条查询结果,搜索用时 31 毫秒
31.
Anita Valmarska Dragana Miljkovic Nada Lavrač Marko Robnik-Šikonja 《Journal of Intelligent Information Systems》2018,51(2):301-337
Parkinson’s disease is a neurodegenerative disorder that affects people worldwide. Careful management of patient’s condition is crucial to ensure the patient’s independence and quality of life. This is achieved by personalized treatment based on individual patient’s symptoms and medical history. The aim of this study is to determine patient groups with similar disease progression patterns coupled with patterns of medications change that lead to the improvement or decline of patients’ quality of life symptoms. To this end, this paper proposes a new methodology for clustering of short time series of patients’ symptoms and prescribed medications data, and time sequence data analysis using skip-grams to monitor disease progression. The results demonstrate that motor and autonomic symptoms are the most informative for evaluating the quality of life of Parkinson’s disease patients. We show that Parkinson’s disease patients can be divided into clusters ordered in accordance with the severity of their symptoms. By following the evolution of symptoms for each patient separately, we were able to determine patterns of medications change which can lead to the improvement or worsening of the patients’ quality of life. 相似文献
32.
In this article, the role of the restoring stiffness, as one of the basic parameters in ship hydroelastic analysis, is brought
out. It is formulated using the variational principle and the method of virtual displacements. It is shown that asymmetry
of the restoring stiffness is a physical reality. Moreover, it is confirmed that modal variation, still disputed in the relevant
literature, has to be taken into account to satisfy the ship’s stability. Consistent stiffness is formulated here by regarding
stiffness definition as relation between forces and displacements. Hybrid stiffness known from the literature is wrong since
some terms are specified as relation between forces and displacement gradient. Influence of the consistent and symmetrized
stiffness matrix, and the hybrid one, on dynamic response is illustrated for a prismatic pontoon and a large container ship.
It is found that the latter two matrices do not assure convergence of transfer functions of sectional forces to zero value
as the wave frequency approaches zero. The rigid body and elastic responses are compared, and pertinent conclusions are drawn.
It is also shown that it is not necessary to use the unified geometric and restoring stiffness for ordinary hydroelastic analysis
of ship structures. The consistent formulation of the restoring stiffness matrix will be useful for extending linear potential
theory hydrodynamic codes for rigid body analysis to deformable bodies. 相似文献
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34.
Dr. Andrija Smelcerovic Dr. Jelena Lazarevic Katarina Tomovic Marija Anastasijevic Dr. Marko Jukic Dr. Gordana Kocic Dr. Marko Anderluh 《ChemMedChem》2019,14(5):514-521
Due to uncomfortable injection regimens of peptidic agonists of glucagon-like peptide-1 receptor (GLP-1R), orally available nonpeptide positive allosteric modulators (PAMs) of GLP-1Rs are foreseen as the possible future mainstream therapy for type 2 diabetes. Herein, current GLP-1R PAMs are reviewed. Based on the effectiveness and in silico predicted physicochemical properties, pharmacokinetics, and toxicity, possible candidates for further development as oral drugs were selected. The suggestion is that GLP-1R PAMs might be used orally alone or in combination with dipeptidyl peptidase-4 (DPP-4) inhibitors, which could offer an optimal treatment option next to metformin monotherapy in type 2 diabetes mellitus, or in a wider spectrum of indications. Quercetin acts as a GLP-1R PAM and DPP-4 inhibitor, and therefore, might be considered as a pioneering agent with a dual mechanism of action, in terms of GLP-1R positive allosteric modulation and DPP-4 inhibition for potentiating GLP-1 dependent effects. 相似文献
35.
An increasing requisite regarding the reproduction quality of electrophotographic printing machines demands improvement of new electrophotographic toner formulation, especially used pigments. The subject of this paper is a comparison of prints realised by depositing high chroma (HC) and standard emulsion aggregation (EA) toner on gloss fine art paper. HC toner has a different composition of the cyan and magenta tones compared with the corresponding standard EA toner tones and therefore behaves differently under real conditions. The patches used for this experiment were cyan and magenta tone prints with tone values (TVs) of 0, 20, 60 and 100%. Ultraviolet (UV) degradation was measured over time intervals of 0, 6, 12, 24, 48, 96, 144 and 240 h for all patches. Results (laboratory values) were calculated using colorimetric difference. Values were plotted as a function of time in tonal degradation graphs. A model was created using non‐linear regression‐based modelling. The experiment demonstrates that magenta patches are more susceptible to degradation in comparison with cyan patches. With the increase in tonal value, it is noticeable that the colorimetric difference is higher. Colorimetric differences calculated using HC magenta toner and standard EA cyan toner (100% TV) were higher than ?E = 5, starting to appear after 6 h of exposure to UV radiance. After 12 h of exposure, colorimetric differences of standard magenta tones that were greater than ?E = 5 also started to appear. Cyan patches (100% TV) printed with HC toner were more stable than the other patches, and after 240 h of exposure had not crossed the boundary of ?E = 5. 相似文献
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38.
Nina Kobal Tjaa Kraovec Maja utar Marija Volk Borut Peterlin Marko Hawlina Ana Fakin 《International journal of molecular sciences》2021,22(4)
Mutations in rhodopsin gene (RHO) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8–71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB (N = 3, 20%) sector RP (N = 3, 20%), pericentral RP (N = 1, 6.7%) and classic RP (N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal–Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report. 相似文献
39.
Communication technologies have been hailed as having a potential to promote democracy and freedom, and this paper aims to examine these claims in a comparative, international context. Our analysis focuses on the mediating role of horizontal communication networks (i.e., telephone, mobile telephone and the Internet) in the relationship between culture and political development. Using cultural value indicators of the World Values Survey and the measures of communication technology development, this study tests the mediating path from culture to communication technologies and to political development. The results suggest that cultural values have a role in shaping the structural characteristics of horizontal networks such as accessibility and decentralization, and that these features of horizontal networks are positively related to institutional and effective democracy as well as to economic competitiveness of nations. 相似文献
40.
Marko J. Tadjer Michael A. Mastro José M. Rojo Alberto Boscá Mojena Fernando Calle Francis J. Kub Charles R. Eddy Jr. 《Journal of Electronic Materials》2014,43(4):1188-1193
Manganese dioxide films were grown on large area flexible carbon aerogel substrates. Characterization by x-ray diffraction confirmed α-MnO2 growth. Three types of films were compared as a function of hexamethylenetetramine (HMTA) concentration during growth. The highest concentration of HM TA produced MnO2 flower-like films, as observed by scanning electron microscopy, whose thickness and surface coverage lead to both a higher specific capacitance and higher series resistance. Specific capacitance was measured to be 64 F/g using a galvanostatic setup, compared to the 47 F/g-specific capacitance of the carbon aerogel substrate. Such supercapacitor devices can be fabricated on large area sheets of carbon aerogel to achieve high total capacitance. 相似文献