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A Super Non-dominated Point for Multi-objective Transportation Problem
Get PDFIn this paper a method to obtain a non-dominated point for the multi-objective transportation problem is presented. The superiority of this method over the other existing methods is that the presented non-dominated point is the closest solution to the ideal solution of that problem. The presented method does not need to have the ideal point and other parameters to find this solution. Also, the calculative load of this method is less than other methods in the literature
Chitosan-based nanocomposite scaffolds for tissue engineering applications
No full textThis article reports the fabrication of three-dimensional porous chitosan and hydroxyapatite (HA)/chitosan composite scaffolds by the thermally induced phase separation (TIPS) technique, for bone tissue engineering. Different amounts of HA nanoparticles (10%, 20%, and 30% g/g) were added to the chitosan solution to produce HA/chitosan composite scaffolds of varying compositions. The morphology and pore structure of the scaffolds vis-à-vis composition were characterized using scanning electron microscopy (SEM) and an energy dispersive X-ray (EDX). Both pure chitosan and HA/chitosan composite scaffolds were highly porous and had interconnected pores. The pore sizes ranged from several micrometers to a few hundred micrometers. The HA nanoparticles were well dispersed and physically coexisted with chitosan in the composite scaffolds. However, some agglomeration of HA nanoparticles was observed on the surface of pore walls when a relatively large amount of HA was used. The composite 3D scaffolds are very promising for use in bone tissue engineering application. © 201
In vitro biological evaluation of electrospun polycaprolactone/gelatine nanofibrous scaffold for tissue engineering
No full textThe fabrication of biocompatible and biodegradable scaffolds which mimic the native extracellular matrix of tissues to promote cell adhesion and growth is emphasized recently. Many polymers have been utilized in scaffold fabrication, but there is still a need to fabricate hydrophilic nanosized fibrous scaffolds with an appropriate degradation rate for skin tissue engineering applications. In this study, nanofibrous scaffolds of a biodegradable synthetic polymer, polycaprolactone (PCL), and blends of PCL with a natural polymer, gelatine (Ge), in three different compositions: 85: 15, 70: 30, and 50: 50 were fabricated via an electrospinning technique. The nanofibrous scaffold prepared from 14% w/v PCL/Ge (70: 30) exhibited more balanced properties of homogeneous nanofibres with an average fibre diameter of 155.60 ± 41.13 nm, 83% porosity, and surface roughness of 176.27 ± 2.53 nm. In vitro cell culture study using human skin fibroblasts (HSF) demonstrated improved cell attachment with a flattened morphology on the PCL/Ge (70: 30) nanofibrous scaffold and accelerated proliferation on day 3 compared to the PCL nanofibrous scaffold. These results show that the PCL/Ge (70: 30) nanofibrous scaffold was more favourable and has the potential to be a promising scaffold for skin tissue engineering applications
Progress and prospects in cryopreservation of stallion sperm
No full textSince the first success of mammalian cell cryopreservation, it has become a major method of cell preservation for both human and veterinary medicine. During the process of cryopreservation, cells undergo osmotic and oxidative stresses that damage cellular structures such as the plasma membranes and DNA.While sperm cryopreservation is an important aspect of equine reproduction having both animal welfare and economic benefits, this advantage is tempered by decreased sperm survival and fertility that falls below that found for sperm of other species. Supplementation of semen extenders with oxidative combatants like antioxidants or various other cryoprotectants has shown positive, but somewhat inconsistent results. This mini-review also assesses the outcomes of current research and future directions for improving post-thaw viability of stallion sperm
Sperm protamine-status correlates to the fertility of breeding bulls
No full textDuring fertilization, spermatozoa make essential contributions to embryo development by providing oocyte activating factors, centrosomal components, and paternal chromosomes. Protamines are essential for proper packaging of sperm DNA; however, in contrast to the studies of oocyte-related female infertility, the influence of sperm chromatin structure on male infertility has not been evaluated extensively. The objective of this study was to determine the sperm chromatin content of bull spermatozoa by evaluating DNA fragmentation, chromatin maturity/protamination, PRM1 protein status, and nuclear shape in spermatozoa from bulls with different fertility. Relationships between protamine 1 (PRM1) and the chromatin integrity were ascertained in spermatozoa from Holstein bulls with varied (high vs. low) but acceptable fertility. Sperm DNA fragmentation and chromatin maturity (protamination) were tested using Halomax assay and toluidine blue staining, respectively. The PRM1 content was assayed using Western blotting and in-gel densitometry, flow cytometry, and immunocytochemistry. Fragmentation of DNA was increased and chromatin maturity significantly reduced in spermatozoa from low-fertility bulls compared to those from high-fertility bulls. Field fertility scores of the bulls were negatively correlated with the percentage of spermatozoa displaying reduced protamination and fragmented DNA using toluidine blue and Halomax, respectively. Bull fertility was also positively correlated with PRM1 content by Western blotting and flow cytometry. However, detection of PRM1 content by Western blotting alone was not predictive of bull fertility. In immunocytochemistry, abnormal spermatozoa showed either a lack of PRM1 or scattered localization in the apical/acrosomal region of the nuclei. The nuclear shape was distorted in spermatozoa from low-fertility bulls. In conclusion, we showed that inadequate amount and localization of PRM1 were associated with defects in sperm chromatin structure, coinciding with reduced fertility in bulls. These findings are highly significant because they reveal molecular and morphological phenotypes of mammalian spermatozoa that influence fertility
Erratum: Impact of maternal HIV seroconversion during pregnancy on early mother to child transmission of HIV (MTCT) measured at 4-8 weeks postpartum in South Africa 2011-2012: A national population- based evaluation
No full textThe TRI-AG Academics Research Extension College Of Agriculture Sciences - October 2015
Get PDFhttps://digitalcommons.pvamu.edu/pv-magazine/1023/thumbnail.jp
A Phenomenological Analysis of African American Students, Delinquent Behaviors and Future Academic Achievement
Get PDFTesting Equality of Locally Stationary Covariances with Application to Mortality Rate Modeling
Get PDFOn factorization of a special type of vandermonde rhotrix
Get PDFVandermonde matrices have important role in many branches of applied mathematics such as combinatorics, coding theory and cryptography. Some authors discuss the Vandermonde rhotrices in the literature for its mathematical enrichment. Here, we introduce a special type of Vandermonde rhotrix and obtain its LR factorization namely left and right triangular factorization, which is further used to obtain the inverse of the rhotrix