33,185 research outputs found
Recommended from our members
Processing of advanced Al/SiC particulate metal matrix composites under intensive shearing â A novel rheo process
Particulate Metal Matrix Composites (PMMCs) have attracted interest for application in numerous fields. The current processing methods often produce agglomerated particles in the ductile matrix and as a result these composites exhibit extremely low ductility. The key idea to solve the current problem is to adopt a novel Rheo-process allowing the application of sufficient shear stress () on particulate clusters embedded in liquid metal to overcome the average cohesive force or the tensile strength of the cluster. In this study, cast A356/SiCp composites were produced using a conventional stir casting technique and a novel Rheo-process. The microstructure and properties were evaluated. The adopted Rheo-process significantly improved the distribution of the reinforcement in the matrix. A good combination of improved Ultimate Tensile Strength (UTS) and tensile elongation (Δ) is obtained
Molecular Mechanisms Involved in Neural Substructure Development during Phosphodiesterase Inhibitor Treatment of Mesenchymal Stem Cells.
Stem cells are highly important in biology due to their unique innate ability to self-renew and differentiate into other specialised cells. In a neurological context, treating major injuries such as traumatic brain injury, spinal cord injury and stroke is a strong basis for research in this area. Mesenchymal stem cells (MSC) are a strong candidate because of their accessibility, compatibility if autologous, high yield and multipotency with a potential to generate neural cells. With the use of small-molecule chemicals, the neural induction of stem cells may occur within minutes or hours. Isobutylmethyl xanthine (IBMX) has been widely used in cocktails to induce neural differentiation. However, the key molecular mechanisms it instigates in the process are largely unknown. In this study we showed that IBMX-treated mesenchymal stem cells induced differentiation within 24 h with the unique expression of several key proteins such as Adapter protein crk, hypoxanthine-guanine phosphoribosyltransferase, DNA topoisomerase 2-beta and Cell division protein kinase 5 (CDK5), vital in linking signalling pathways. Furthermore, the increased expression of basic fibroblast growth factor in treated cells promotes phosphatidylinositol 3-kinase (PI3K), mitogen-activated protein kinase (MAPK) cascades and GTPase-Hras interactions. Bioinformatic and pathway analyses revealed upregulation in expression and an increase in the number of proteins with biological ontologies related to neural development and substructure formation. These findings enhance the understanding of the utility of IBMX in MSC neural differentiation and its involvement in neurite substructure development
Influence of affluence on sustainable housing in Mysore, India
Mysore, the second largest city in the state of Karnataka, India, can be identified as an early adopter of sustainable design practices. Between 1903 and 1947 the use of local construction materials, the Swadeshi movement of 1905, robust planning and clear legislation resulted in sustainable urban development. However, post-colonial development fuelled by economic globalisation after the 1980s has transformed perceptions of the house among the growing middle class, becoming a commodity to demonstrate affluence and status. This paper examines the impact of changing social and cultural values on the aspirations of the growing middle classes on sustainable housing and neighbourhood development in Mysore. The methodology comprises literature and archive research to establish the historical content and review some important recent trends. Extensive fieldwork studies, including questionnaires over a wide range of participants (owners, builders and designers) and semistructured interviews with key players, including academics, architects and government agencies. The focus of development has shifted from community to individual, from energy conserving to a more consumerist attitude in the procurement of materials and finishes. The paper examines the impact of these changes. The results of the survey are summarised and reviewed under the categories of communities, site, entrance, house layout and materials
Best Practices in Second Stage Labor Care: Maternal Bearing Down and Positioning
Despite evidence of adverse fetal and maternal outcomes from the use of sustained Valsalva bearing down efforts, current second-stage care practices are still characterized by uniform directions to âpushâ forcefully upon complete dilatation of the cervix while the woman is in a supine position. Directed pushing might slightly shorten the duration of second stage labor, but can also contribute to deoxygenation of the fetus; cause damage to urinary, pelvic, and perineal structures; and challenge a womanâs confidence in her body. Research on the second stage of labor care is reviewed, with a focus on recent literature on maternal bearing down efforts, the âlaboring downâ approach to care, second-stage duration, and maternal position. Clinicians can apply the scientific evidence regarding the detrimental effects of sustained Valsalva bearing down efforts and supine positioning by individualizing second stage labor care and supporting womenâs involuntary bearing down sensations that can serve to guide her behaviors
Valproic Acid Promotes Early Neural Differentiation in Adult Mesenchymal Stem Cells Through Protein Signalling Pathways.
Regenerative medicine is a rapidly expanding area in research and clinical applications. Therapies involving the use of small molecule chemicals aim to simplify the creation of specific drugs for clinical applications. Adult mesenchymal stem cells have recently shown the capacity to differentiate into several cell types applicable for regenerative medicine (specifically neural cells, using chemicals). Valproic acid was an ideal candidate due to its clinical stability. It has been implicated in the induction of neural differentiation; however, the mechanism and the downstream events were not known. In this study, we showed that using valproic acid on adult mesenchymal stem cells induced neural differentiation within 24 h by upregulating the expression of suppressor of cytokine signaling 5 (SOCS5) and Fibroblast growth factor 21 (FGF21), without increasing the potential death rate of the cells. Through this, the Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway is downregulated, and the mitogen-activated protein kinase (MAPK) cascade is activated. The bioinformatics analyses revealed the expression of several neuro-specific proteins as well as a range of functional and structural proteins involved in the formation and development of the neural cells
Establishment of sorghum cell suspension culture system for proteomics studies
This study describes the establishment of sorghum cell suspension culture system for use in proteomics studies. Friable sorghum callus was initiated from young shoots under completely dark conditions on MS medium supplemented with 3 mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) and 2.5 mg/L 1-naphthaleneacetic acid (NAA). Additionally, sorghum cell suspension cultures have been initiated from the friable callus masses in liquid medium with the same composition as the callusinitiation medium. Total soluble proteins (TSP) and culture filtrate (CF) proteins were extracted from the cell culture system and solubilised in urea buffer (9 M urea, 2 M thiourea and 4% CHAPS). Both onedimensional (1D) and two-dimensional (2D) gel analysis of these two proteomes show that the TSP and CF proteomes have different protein expression profiles. The sorghum TSP proteome, which is highlycomplex, is best resolved when separated on large format, 18 cm, pH 4 - 7 isoelectric focusing (IEF) immobilised pH gradient (IPG) strips. On the other hand, the sorghum CF proteome (secretome) is lesscomplex with most proteins being resolved on mini format, 7 cm, pH 3 - 10 IPG strips. Furthermore, narrowing down the pH range from 3 - 10 to 4 - 7 for the CF proteome resulted in improved protein spotresolution
Pattern Formation in Semiconductors
In semiconductors, nonlinear generation and recombination processes of free carriers and nonlinear charge transport can give rise to non-equilibrium phase transitions. At low temperatures, the basic nonlinearity is due to the autocatalytic generation of free carriers by impact ionization of shallow impurities. The electric field accelerates free electrons, causing an abrupt increase in free carrier density at a critical electric field. In static electric fields, this nonlinearity is known to yield complex filamentary current patterns bound to electric contacts
Development of syrup and âmalt-likeâ drink from Raphia hookeri sap
Natural microflora fermentation causes changes in freshly tapped palm sap and therefore makes its storage, transport, and large scale use difficult. This study was aimed at developing stable and value added products, including syrup and non-alcoholic “malt-like” drink from the sap of palms. The sap of Raphia hookeri collected from “evening-to-morning”(1700 Hrs-0700 Hrs) and “morning-to-afternoon” (0700 Hrs-1600 Hrs), respectively, were used in the preparation of syrup. The respective syrups were in turn used in combination with varying proportions of water, sugar, and caramel for the formulation of six(6) palm “malt-like” drinks from which the best (from sensory evaluation) was carbonated and named Palm Malt. The prepared Palm Malt was compared to commercially popular malt drinks on the market. A nine point hedonic scale (1=like extremely – 9=dislike extremely) was used by a panel of 56 to evaluate the colour, taste, flavour and after-taste, as well as overall consumer acceptability of the product. Proximate and physicochemical analyses were also carried out on the sap, syrup and Palm Malt using standard procedures. Descriptive statistics (percentages, mean and standard deviation) were derived and data were also subjected to regression analysis to determine relations between parameters. Analysis of variance (ANOVA) was used to determine variations in properties. Results of the proximate analyses showed that the moisture and protein content of the sap samples ranged from 92.96-94.21% and 0.14-0.17% respectively, with an average ash content of 1.53%. That for the syrup ranged from 13.45-15.60% and 0.14-0.17%, respectively, with ash content of 1.70%. Potassium, the principal cation in body cells, was the most abundant mineral in the saps. Physicochemical results: pH and total sugars of the saps were found to be 3.94-4.05, and 6.53-7.57%, respectively; whereas that for the syrups was found to be 3.96-4.13 and 76.70-82.03% respectively. The pH, total soluble solids, total solids and titratable acidity of the developed Palm Malt were found to be 4.94, 14.50%, 15.86%, 0.55%, respectively. The developed Palm Malt was found to be equally acceptable to consumers, in comparison to commercially popular types of malt drinks (P>0.05). This shows that there is potential for economic utilization of palm sap. If exploited, this would contribute to increased income for farmers and industrialists in the regions of Ghana/Africa where palms grow.Keywords: Raphia hookeri, sap, syrup, malt-like drin
Low temperature scattering with the R-matrix method: the Morse potential
Experiments are starting to probe collisions and chemical reactions between
atoms and molecules at ultra-low temperatures. We have developed a new
theoretical procedure for studying these collisions using the R-matrix method.
Here this method is tested for the atom -- atom collisions described by a Morse
potential. Analytic solutions for continuum states of the Morse potential are
derived and compared with numerical results computed using an R-matrix method
where the inner region wavefunctions are obtained using a standard nuclear
motion algorithm. Results are given for eigenphases and scattering lengths.
Excellent agreement is obtained in all cases. Progress in developing a general
procedure for treating ultra-low energy reactive and non-reactive collisions is
discussed.Comment: 18 pages, 6 figures, 3 tables, conferenc
- âŠ