82 research outputs found
Method for studing the multi-solitone solutions of the korteweg de-vries type equations based on the T-transformation
Запропоновано новий підхід до знаходження часткових розв’язків диференціальних рівнянь у частинних похідних, які моделюють одиночну хвилю. Відповідний підхід грунтується на використанні Т-представлень розв’язків. На цій основі знайдено новий клас солітонних розв’язків рівняння Кортевега де-Вріза та доведено, що відомий солітон рівняння КдВ є частковим випадком запропонованого нами представлення. Запропонований метод може бути застосований і до інших диференціальних рівнянь. Підхід, що грунтується на основі Т-представлень розв’язків, також може бути використаний для знаходження багатосолітонних розв’язків. У роботі запропоновано метод дослідження взаємодії одиночних хвиль. Відповідний метод продемонстровано на прикладі рівняння Кортевега де-Вріза та отримано двосолітонний розв’язок цього рівняння. Методи, запропоновані в даній роботі, можуть стати основою для досліджень одиночних хвиль та солітонів у рамках інших моделей, що описуються системами диференціальних рівнянь у частинних похідних.In recent years the investigation of separated waves plays an important role in many applied scientific fields. Travelling wave solutions can describe various phenomena in fluid mechanics, hydrodynamics, optics, plasma physics, solid state physics, biology, meteorology and other fields. There are many models proposed to describe the physical phenomena of separated waves existence and variety of methods has been proposed to construct the exact and approximate solutions to nonlinear equations. In this paper, we propose a new technique of finding the PDE’s traveling wave solutions, which are based on the T- representation. This generalized representation of solutions has the advantages of classical δ-solitons in terms of their independence from the shape and profile, however, allowed to obtain limited smooth solution that simulates solitary waves.This technique guarantees isolation of a solution and allows to investigate the infinitesimal properties. Using T-representation method we found a new class of KdV solution, which simulate solitary wave and proved that well known KdV solution is a special case of our generalizations. The proposed method can be applied to finding solutions of a wide class of differential equations in partial derivatives in the form of solitary waves . T-representations can be useful for the investigation of multi-soliton solutions. Method for studying multi-soliton solutions is demonstrated on the example of KdV solutions. Multi-soliton solutions are represented as the sum of the T-representations with variable amplitudes. In this case, there are exact solutions for the amplitudes of the perturbations in special areas, which are determined by the maximum of perturbations. Problem of searching the perturbation amplitude is reduced to the Cauchy problem for some initial conditions. Changing conditions for maximum localization of perturbation we cover the area of solitones intersection by a system of curves, where exact solutions for the amplitude functions are found. For an approximate description of the waves interaction quite a few curves are needed. This approach allows to consider different laws of waves motion and simulate their amplitude in the region of intersection. An example of computer simulation is presented in this paper
Utjecaj različitih površinski aktivnih tvari i njihovih koncentracija na kontrolirano oslobađanje kaptoprila iz polimernih matriksa
Various methods are available to formulate water soluble drugs into sustained release dosage forms by retarding the dissolution rate. One of the methods used to control drug release and thereby prolong therapeutic activity is to use hydrophilic and lipophilic polymers. In this study, the effects of various polymers such as hydroxypropyl methylcellulose (HPMC), ethylcellulose (EC) and sodium carboxymethylcellulose (CMC) and surfactants (sodium lauryl sulphate, cetyltrimethylammonium bromide and Arlacel 60) on the release rate of captopril were investigated. The results showed that an increase in the amount of HPMC K15M resulted in reduction of the release rate of captopril from these matrices. When HPMC was partly replaced by NaCMC (the ratio of HPMC/NaCMC was 5:1), the release rate of the drug significantly decreased. However, there was no significant difference in release rate of captopril from matrices produced with ratios of 5:1 and 2:1 of HPMC/NaCMC. The presence of lactose in matrices containing HPMC and NaCMC increased the release rate of captopril. It was interesting to note that although partial replacement of HPMC by EC reduced the release rate of the drug (ratio of HPMC/EC 2:1), the release rate was increased when the ratio of HPMC/EC was reduced to 1:1. The effects of various surfactants on the release rate of captopril from HPMC/EC 1:1 matrices were also investigated. The results showed that the surfactants did not significantly change the release rate of the drug. Release data were examined kinetically and the ideal kinetic models were estimated for the drug release. The kinetic analysis of drug release data from various formulations showed that incorporation of surfactants in HPMC/EC matrices did not produce a zero-order release pattern.Postoje različite metode formuliranja vodotopljivih lijekova u dozirane ljekovite oblike s polaganim oslobađanjem. Jedan od načina postizanja kontroliranog otpuštanja, a prema tome i produljenog učinka je upotreba hidrofilnih i lipofilnih polimera. U ovom radu proučavan je utjecaj različitih polimera poput hidroksipropil metilceluloze (HPMC), etilceluloze (EC) i natrijeve soli karboksimetilceluloze (NaCMC) i površinski aktivnih tvari (natrijevog lauril-sulfata, cetiltrimetilamonijevog bromida i Arlacela 60) na oslobađanje kaptoprila. Rezultati pokazuju da povećanje količine HPMC K15M ima za posljedicu smanjenje oslobađanja kaptoprila iz matriksa. Ako se HPMC djelomično zamijeni s NaCMC (omjer HPMC/NaCMC 5:1), oslobađanje ljekovite tvari značajno se smanjuje. Međutim, nema značajne razlike u oslobađanju kaptoprila iz matriksa s omjerom HPMC/NaCMC 5:1 i 2:1. Prisutnost laktoze u matriksu koji sadrži HPMC i NaCMC povećalo je oslobađanje kaptoprila. Iako djelomična zamjena HPMC s EC smanjuje oslobađanje ljekovite tvari (omjer HPMC/EC 2:1), oslobađanje se povećava uz omjer HPMC/EC 1:1. Nadalje, ispitivan je utjecaj površinski aktivnih tvari na oslobađanje kaptoprila iz matriksa u kojima je omjer HPMC/EC (1:1). Može se zaključiti da površinski aktivne tvari ne utječu značajno na oslobađanje ljekovite tvari. U sklopu istraživanja određen je i kinetički model oslobađanja kaptoprila. Analiza kinetičkih podataka ukazuje da dodatak površinski aktivnih tvari u HPMC/EC matrikse ne slijedi kinetiku nultog reda
Fish Oil Enhances Recovery of Intestinal Microbiota and Epithelial Integrity in Chronic Rejection of Intestinal Transplant
The intestinal chronic rejection (CR) is the major limitation to long-term survival of transplanted organs. This study aimed to investigate the interaction between intestinal microbiota and epithelial integrity in chronic rejection of intestinal transplantation, and to find out whether fish oil enhances recovery of intestinal microbiota and epithelial integrity.. In addition, CR rats showed pronounced alteration of tight junction, depicted by marked changes in epithelial cell ultrastructure and redistribution of occuldin and claudins as well as disruption in TJ barrier function. Fish oil administration ameliorated disruption of epithelial integrity in CR, which was associated with an improvement of the mucosal structure leading to improved tight junctions.Our study have presented novel evidence that fish oil is involved in the maintenance of epithelial TJ integrity and recovery of gut microbiota, which may have therapeutic potential against CR in intestinal transplantation
An atlas of genetic scores to predict multi-omic traits
The use of omic modalities to dissect the molecular underpinnings of common diseases and traits is becoming increasingly common. But multi-omic traits can be genetically predicted, which enables highly cost-effective and powerful analyses for studies that do not have multi-omics1. Here we examine a large cohort (the INTERVAL study2; n = 50,000 participants) with extensive multi-omic data for plasma proteomics (SomaScan, n = 3,175; Olink, n = 4,822), plasma metabolomics (Metabolon HD4, n = 8,153), serum metabolomics (Nightingale, n = 37,359) and whole-blood Illumina RNA sequencing (n = 4,136), and use machine learning to train genetic scores for 17,227 molecular traits, including 10,521 that reach Bonferroni-adjusted significance. We evaluate the performance of genetic scores through external validation across cohorts of individuals of European, Asian and African American ancestries. In addition, we show the utility of these multi-omic genetic scores by quantifying the genetic control of biological pathways and by generating a synthetic multi-omic dataset of the UK Biobank3 to identify disease associations using a phenome-wide scan. We highlight a series of biological insights with regard to genetic mechanisms in metabolism and canonical pathway associations with disease; for example, JAK-STAT signalling and coronary atherosclerosis. Finally, we develop a portal ( https://www.omicspred.org/ ) to facilitate public access to all genetic scores and validation results, as well as to serve as a platform for future extensions and enhancements of multi-omic genetic scores
Zebuines kerngenom und taurine Mitochondrien: admixtur von Nelore, der größten brasilianischen rinderrasse.
The beef industry is a major employment industry in Brazil and the country is currently the world’s third largest exporter of beef. From the mid-1950s to the mid-1960s, thousands of zebus were imported from India, establishing the meat breed Nelore (or Nellore). This study uses cluster analysis methods, implemented by the “admixture” software, to analyze the proportion of indicine and taurine genetic material in the current Nelore population. angus, Fleckvieh, Hereford, Holstein Friesian, Limousin and Piedmontese cattle breeds are used as taurine references. ancestral Nelore and Gir animals and the Brahman cattle breed serve as the indicine references
Genetic Drivers of Epigenetic and Transcriptional Variation in Human Immune Cells
Characterizing the multifaceted contribution of genetic and epigenetic factors to disease phenotypes is a major challenge in human genetics and medicine. We carried out high-resolution genetic, epigenetic, and transcriptomic profiling in three major human immune cell types (CD14 monocytes, CD16 neutrophils, and naive CD4 T cells) from up to 197 individuals. We assess, quantitatively, the relative contribution of -genetic and epigenetic factors to transcription and evaluate their impact as potential sources of confounding in epigenome-wide association studies. Further, we characterize highly coordinated genetic effects on gene expression, methylation, and histone variation through quantitative trait locus (QTL) mapping and allele-specific (AS) analyses. Finally, we demonstrate colocalization of molecular trait QTLs at 345 unique immune disease loci. This expansive, high-resolution atlas of multi-omics changes yields insights into cell-type-specific correlation between diverse genomic inputs, more generalizable correlations between these inputs, and defines molecular events that may underpin complex disease risk.This work was predominantly funded by the EU FP7 High Impact Project BLUEPRINT (HEALTH-F5-2011-282510) and the Canadian Institutes of Health Research (CIHR EP1-120608). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 282510 (BLUEPRINT), the European Molecular Biology Laboratory, the Max Planck society, the Spanish Ministry of Economy and Competitiveness, ‘Centro de Excelencia Severo Ochoa 2013-2017’, SEV-2012-0208 and Spanish National Bioinformatics Institute (INB-ISCIII) PT13/0001/0021 co-funded by FEDER "“Una Manera de hacer Europa”. D.G. is supported by a “la Caixa”-Severo Ochoa pre-doctoral fellowship, M.F. was supported by the BHF Cambridge Centre of Excellence [RE/13/6/30180], K.D. is funded as a HSST trainee by NHS Health Education England, S.E. is supported by a fellowship from La Caixa, V.P. is supported by a FEBS long-term fellowship and N.S.'s research is supported by the Wellcome Trust (Grant Codes WT098051 and WT091310), the EU FP7 (EPIGENESYS Grant Code 257082 and BLUEPRINT Grant Code HEALTH-F5-2011-282510) and the NIHR BRC. The Blood and Transplant Unit (BTRU) in Donor Health and Genomics is part of and funded by the National Institute for Health Research (NIHR) and is a partnership between the University of Cambridge and NHS Blood and Transplant (NHSBT) in collaboration with the University of Oxford and the Wellcome Trust Sanger Institute. The T-cell data was produced by the McGill Epigenomics Mapping Centre (EMC McGill). It is funded under the Canadian Epigenetics, Environment, and Health Research Consortium (CEEHRC) by the Canadian Institutes of Health Research and by Genome Quebec (CIHR EP1-120608), with additional support from Genome Canada and FRSQ. T.P. holds a Canada Research Chair
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Reproductive health and lifestyle factors associated with health-related quality of life among perinatally HIV-infected adolescents in Uganda
Background
With increased survival of perinatally HIV - infected adolescents due to antiretroviral therapy (ART), the focus of HIV care has shifted to health-related quality of life (HRQoL) as a measure of disease progression, effects of ART co-morbidity and prognosis. We assessed factors associated with better HRQoL in perinatally HIV -infected adolescents in Uganda by determining the associations between sexual and reproductive health (SRH) or lifestyle experiences on HRQoL.
Methods
In a cross-sectional study, data on SRH, lifestyle experiences, socio demographic factors, communication with parents on sexuality and satisfaction of SRH services in ART clinics were collected from 614 HIV perinatally infected adolescents aged 10–19 using an interviewer-administered survey questionnaire. HRQoL data were collected using the Medical Outcomes Study HIV Health Survey instrument (MOS-HIV). Factors associated with better HRQoL were analysed using multiple logistic regression.
Results
The mean age was 16.2 ± 2.1 years, 362 (58.8 %) were females and 210 (34.2 %) were sexually active. Adolescents on ART were twice likely to present with better physical health (AOR = 2.07, 95 % CI: 1.24–3.46) and four times more likely to present with better mental health (AOR = 3.9, 95 % CI: 2.22–6.92) than those who were not on ART. There were no statistically significant associations between SRH (ever had sex, ever been pregnant, condom use, contraceptive use) or life style factors and physical health or mental health. Those with secondary or tertiary education were more likely to present with a better mental health (AOR = 5.3, 95 % CI: 1.86–15.41) compared those who had attained primary or no education. Participants who desired to have a child in future more likely (AOR 1.7, 95 % CI: 1.05–3.00) to present with a better mental health. Lack of communication with guardians on sexuality (AOR = 0.6, 95 % CI: 0.40–0.89), or dissatisfaction with SRH services (AOR 0.34, 95 % CI: 0.18–0.62) were associated with poorer mental health.
Conclusion
Among perinatally HIV-infected adolescents in Uganda, being on ART was associated with better physical and mental health while lack of communication with guardians on sexuality or dissatisfaction with SRH services was associated with poor mental health. Adolescents with pregnancy intentions were more likely to have a better mental health
Atypical Neurophysiology Underlying Episodic and Semantic Memory in Adults with Autism Spectrum Disorder
Individuals with autism spectrum disorder (ASD) show atypicalities in episodic memory (Boucher et al. in Psychological Bulletin, 138 (3), 458-496, 2012). We asked participants to recall the colours of a set of studied line drawings (episodic judgement), or to recognize line drawings alone (semantic judgement). Cycowicz et al. (Journal of Experimental Child Psychology, 65, 171-237, 2001) found early (300 ms onset) posterior old-new event-related potential effects for semantic judgements in typically developing (TD) individuals, and occipitally focused negativity (800 ms onset) for episodic judgements. Our results replicated findings in TD individuals and demonstrate attenuated early old-new effects in ASD. Late posterior negativity was present in the ASD group, but was not specific to this time window. This non-specificity may contribute to the atypical episodic memory judgements characteristic of individuals with ASD
Potential neoplastic evolution of Vero cells: in vivo and in vitro characterization
Vero cell lines are extensively employed in viral vaccine manufacturing. Similarly to all established cells, mutations can occur during Vero cells in vitro amplification which can result in adverse features compromising their biological safety. To evaluate the potential neoplastic evolution of these cells, in vitro transformation test, gene expression analysis and karyotyping were compared among low- (127 and 139 passages) and high-passage (passage 194) cell lines, as well as transformed colonies (TCs). In vivo tumorigenicity was also tested to confirm preliminary in vitro data obtained for low passage lines and TCs. Moreover, Vero cells cultivated in foetal bovine serum-free medium and derived from TCs were analysed to investigate the influence of cultivation methods on tumorigenic evolution. Low-passage Vero developed TCs in soft agar, without showing any tumorigenic evolution when inoculated in the animal model. Karyotyping showed a
hypo-diploid modal chromosome number and rearrangements with no difference among Vero cell line passages and TCs. These abnormalities were reported also in serum-free cultivated Vero. Gene expression revealed that high-passage Vero cells had several under-expressedand a few over-expressed genes compared to low-passage ones.Gene ontology revealed no significant enrichment of pathways related to oncogenic risk. These findings suggest that in vitro high passage, and not culture conditions, induces Vero transformation correlated to karyotype and gene expression alterations. These data, together with previous investigations reporting tumour induction in high-passage Vero cells, suggest the use of low-passage Vero cells or cell lines other than Vero to increase the safety of vaccine manufacturing
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