107 research outputs found
Investigation of Adding Microscopic Slide Glass Nano Particles on the Metallurgical Characterization and Mechanical Properties of Cast Aluminum 7075 Composites
Abstract. Metal Matrix Composite (MCC) exhibits significantly better properties, like hardness, high tensile strength, low density, and good wear resistance compared to alloy or any other metals. In the present study, the effect of using different proportions (2, 4, 8 and 10 wt.%) of microscopic slide glass nano particles (MSGNP) on the properties of Al-7075 alloy was investigated. The results of the experimental investigation of the metallurgical characterization and mechanical properties of aluminum MMC that formed by stir casting were obtained. Stir casting is the process of introducing a reinforcing material into a molten metal by stirring it in. The results of the aluminum MMC were compared with those for the base alloy material. Optical microscopy, scanning electron microscope (SEM), energy dispersive spectroscopy (EDX), and X-Ray Diffraction study (XRD) were carried out to analyze the microstructure and the dispersion of the (MSGNP) into the composite alloy specimens. Regarding the mechanical properties, the Rockwell hardness gradually increased when the addition of MSGNP was raised from 0 to 10wt.%. Also, there was an increase in the ultimate tensile strength, peaking at the incorporation rate of 4wt.% MSGNP and thereafter, this strength deteriorated. Therefore, the addition of microscopic slide glass nano particles to the Al-7075 is good for enhancing the alloy properties for engineering application
Gibberellic acid effects on protein pattern, hydrolytic enzyme activities and ionic uptake during germination of Vicia faba in sea water
The germination and water uptake of Vicia faba seeds were suppressed in response to the treatments with the different concentrations of sea water (5%, 25% and 50%). The following parameters were increased: the osmotic potential, Na+, Cl, proline and protease activity. While K+, K+/Na+ ratio, Ca2+, amylase activity and total soluble sugars were decreased. Gibberellic acid treatments to the seeds counteracted the harmful effect which were induced by sea water treatments. In turn the germination percentage, water uptake, K+, K+/Na+ ratio, Ca2+, total soluble sugars, a-amylase and protease activities were increased, while Na+, Cl, and proline were decreased. The changes in protein banding pattern in Vicia faba germinated seeds in sea water were investigated. Salinization induced de novo synthesis of some salt responsive proteins. The salt responsive proteins might be osmotin (M wt 23.39 and 26.86 KDa), dehydrin (36.79 and 40.63 KDa) and ubiquitin (8.81 KDa) which were apparent in Vicia faba seeds. The seeds priming soaking in GA and germinated in sea water induced de novo synthesis of some responsive proteins. This indicated that gibberellic acid had a synergistic effect on the induction of the salt gene which is responsible for the synthesis of the mentioned proteins
Modelling Referencing Competency and Individual Performance
Competency is the ability to perform a task efficiently and effectively. One of the necessary skills students need is writing, understanding, and formatting the references section of their work. However, knowledge of this competency is non-existent or unknown in the field of Library and Information Science (LIS). Therefore, the purpose of this study is to investigate the relationship between referencing competencies and individual’s performance in the context of undergraduate students. A quantitative method was adopted; 292 respondents were involved, selected from undergraduate students at one of the Malaysian local universities. Descriptive analysis was performed using Statistical Package for Social Sciences (SPSS) version 26. On the other hand, inferential analysis was performed using Partial Least Square Structural Equation Modelling using SmartPLS version 3.2.8. Findings show that knowledge, skills, and ability positively and significantly affect individual performance.https://dorl.net/dor/ 20.1001.1.20088302.2022.20.1.23.
Structural and Functional adaptation of the lingual papillae of the Egyptian fruit bat (Rousettus aegyptiacus): Specific Adaptive feeding Strategies
The current investigation was directed to clarify the correlations between the feeding strategy and lingual structure of the Egyptian fruit bat captured from the Egyptian east desert. The current work depends on twelve adult Egyptian fruit bats that observed grossly and with the help of the stereo, light, and scanning electron microscope. There were three types of the lingual papillae; one mechanical filiform and two gustatory (fungiform and circumvallate). There were seven subtypes of filiform papillae were recognized on the seven lingual regions. There were scanty numbers of fungiform papillae distributed among the filiform papillae on the lingual tip and two lateral parts of apex and body while fungiform papillae completely absent in the median part. There were three circumvallate papillae. The central bulb of circumvallate papillae surrounded by one layer of two segmented circular annular bad. The lingual tip had cornflower-like and diamond-shaped filiform papillae. Histochemical results revealed that the lingual glands were a stronger AB-positive reaction and gave dark blue color, while the reaction for the PAS-stain was negative. Also, the glands exhibited a blue color as an indication of positive AB reactivity with combined AB-PAS staining
Acute Human Self-Poisoning with Imidacloprid Compound: A Neonicotinoid Insecticide
Background: Deliberate self-poisoning with older pesticides such as organophosphorus compounds are commonly fatal and a serious public health problem in the developing world. The clinical consequences of self-poisoning with newer pesticides are not well described. Such information may help to improve clinical management and inform pesticide regulators of their relative toxicity. This study reports the clinical outcomes and toxicokinetics of the neonicotinoid insecticide imidacloprid following acute self-poisoning in humans. Methodology/Principal Findings: Demographic and clinical data were prospectively recorded in patients with imidacloprid exposure in three hospitals in Sri Lanka. Blood samples were collected when possible for quantification of imidacloprid concentration. There were 68 patients (61 self-ingestions and 7 dermal exposures) with exposure to imidacloprid. Of the self-poisoning patients, the median time to presentation was 4 hours (IQR 2.3–6.0) and median amount ingested was 15 mL (IQR 10–50 mL). Most patients only developed mild symptoms such as nausea, vomiting, headache and diarrhoea. One patient developed respiratory failure needing mechanical ventilation while another was admitted to intensive care due to prolonged sedation. There were no deaths. Median admission imidacloprid concentration was 10.58 ng/L; IQR: 3.84–15.58 ng/L, Range: 0.02–51.25 ng/L. Changes in the concentration of imidacloprid in serial blood samples were consistent with prolonged absorption and/or saturable elimination. Conclusions: Imidacloprid generally demonstrates low human lethality even in large ingestions. Respiratory failure and reduced level of consciousness were the most serious complications, but these were uncommon. Substitution of imidacloprid for organophosphorus compounds in areas where the incidence of self-poisoning is high may help reduce deaths from self-poisoning
Dietary clenbuterol modifies the expression of genes involved in the regulation of lipid metabolism and growth in the liver, skeletal muscle, and adipose tissue of Nile tilapia (Oreochromis niloticus)
The current study aimed to evaluate whether clenbuterol, a β2-adrenergic agonist, supplementation in Nile tilapia (Oreochromis niloticus) diets can influence growth and blood parameters. Besides, assessment of adipogenic genes as fatty acid synthase (FAS) and lipoprotein lipase (LPL) which is a key enzyme in the regulation of the flux of fatty acids in liver, muscle, and adipose tissue as well as muscle growth-regulating genes as myostatin (MYO) in muscle and insulin-like growth factor-1 (IGF-1) in liver. The fish were allocated into three equal groups; control group that fed basal diet only and the other two groups fed a basal diet containing clenbuterol at two doses 5 ppm and 10 ppm/kg diet for 30 consecutive days. Results revealed that clenbuterol supplementation significantly increased body weight, decreased liver, spleen and abdominal fat weights, and decreased total circulatory cholesterol and triacylglycerol levels. Moreover, clenbuterol inhibits lipogenesis by downregulation of FAS gene expression by dose and time-dependent manner in the liver while enhanced lipolysis in both the liver and in the adipose tissue. Moreover, lipolysis was reduced in muscle by dose 10 ppm on day 30. Furthermore, clenbuterol presented higher gene expression of MYO and IGF-1 in muscle and liver respectively by dose 5 ppm at day 15 on the other hand, these findings were reversed by day 30 compared with control. In conclusion, clenbuterol efficacy was apparent in a dose and time response pattern to boost growth and reduce fat deposition rates, indicating for the first time that clenbuterol has a profitable growth impact on Nile tilapia
Growth performance, blood lipids, and fat digestibility of broilers fed diets supplemented with bile acid and xylanase
This study aimed to show the effect of bile acid (BA) and xylanase (Xyl) supplementation on the growth, fat digestibility, serum lipid metabolites, and ileal digesta viscosity of broilers. A total of 720 1 d old male broilers were allocated to one of nine treatments with four replicates in each under a factorial design arrangement of three levels of BA (0 %, 0.25 %, and 0.50 %) and three levels of Xyl (0 %, 0.05 %, and 0.10 %) supplementation. The duration of the experiment was 35 d (7–42 d). Growth performance, blood lipids, fat digestibility, and ileal digesta viscosity were determined. The experimental treatments did not affect feed intake (FI) and weight gain (WG). Supplementation of BA or Xyl did not significantly ameliorate the feed conversion rate (FCR) (p<0.05). The addition of BA linearly increased fat digestibility. At 7–21 d of age, the addition of BA or Xyl had a significant (p<0.05) increase in serum cholesterol (Chol) but no significant difference for other serum lipid parameters in broiler chickens fed with Xyl in the starter and grower periods. However, the supplementation of 0.5 % BA at 7–21 d of age significantly increased the Chol and low-density-lipoprotein (LDL) levels. The results of this trial revealed that the supplementation of xylanases had a great effect on the degradation of arabinoxylan from wheat, which led to a relatively greater reduction in ileal digesta viscosity; it was also found that supplementation of BA significantly increased the concentration of serum lipid metabolites, whereas BA and Xyl supplementation linearly increased the fat digestibility of the birds fed wheat and tallow diets.</p
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