120 research outputs found

    Fabrication of mesoscale topographical gradients in bulk titanium and their use in injection moulding

    Get PDF
    Fabrication methods for titanium substrates exhibiting continuous micro and nano scale arrays, with increasing feature heights over the length of the array are reported. The resultant feature heights spanned 0–2 μm. Patterned gradient arrays of circular features with diameters of: 500 nm, 1 μm and 2 μm, spaced by twice the diameter were manufactured by the process using specially prepared titanium substrates. Patterns were exposed by electron beam lithography and the length of the patterned arrays was 15 mm or 20 mm. This work presents two selectivity amplification processes to achieve a gradient of feature heights ranging over the titanium array after consecutive reactive ion etching processes. The first, route A: a HSQ on Ti, gradient amplification process. The second, route B, a SiO2 layer amplification transfer into Ti. The crucial initial gradient component deposited for the amplification process for both routes was a diffusion limited plasma polymerised hexane gradient. Etching using respective reactive ion etch chemistries for each gradient transfer through the various selectivity amplification layers (employing consecutive etch steps, in this way) enables a dual amplification for each route to manufacture. The original gradient is transferred into titanium as a function of the sum of the respective selectivities between the materials, using the appropriate dry etch plasma conditions. The substrates henceforth are referred to as inlays, and were tested for use as a high throughput platform for polymer replication by injection moulding. It is envisaged that the fabrication methodology and resultant topographies have use in a range of engineering applications. The overall selectivity to Ti for polymerised hexane is increased by more than 20 times using each dual amplification process

    Integration of Financial and ESG Performance Indicators to Measure and Evaluate Egyptian Insurance Companies Performance

    Get PDF
    This study aims to evaluate the performance of Egyptian insurance companies through the integration of financial and non-financial performance indicators through the dimensions of sustainable development as a mediator variable. The study relied on Allianz Egypt property and liability insurance company data from 2012 to 2021, and the Monte Carlo simulation method was used based on the Mathcad program. This study used structural Equations Modeling via AMOS program to extract the direct and indirect effect through path analysis. The results showed that each environmental dimension, social dimension, and governance dimension plays a mediator role in the relationship between solvency, liquidity, credit, activity, underwriting profitability, and both market share and investment profitability. Our research contributes to the literature of achieving sustainable development in the insurance sector, to keep pace with global developments. This paper presents evidence of the relationship between integrating ESG indicators into insurance companies’ performance and achieving an additional competitive advantage

    Effect of corn supplementation on purine derivatives and rumen fermentation in sheep fed PKC and urea-treated rice straw

    Get PDF
    This study investigated the effect of different levels of corn supplementation as energy source into palm kernel cake–urea-treated rice straw basal diet on urinary excretion of purine derivatives, nitrogen utilization, rumen fermentation, and rumen microorganism populations. Twenty-seven Dorper lambs were randomly assigned to three treatment groups and kept in individual pens for a 120-day period. The animals were subjected to the dietary treatments as follows: T1: 75.3% PKC + 0% corn, T2: 70.3% PKC + 5% corn, and T3: 65.3% PKC + 10% corn. Hypoxanthine and uric acid excretion level were recorded similarly in lambs supplemented with corn. The microbial N yield and butyrate level was higher in corn-supplemented group, but fecal N excretion, T3 has the lowest level than other groups. Lambs fed T3 had a greater rumen protozoa population while the number of R. flavefaciens was recorded highest in T2. No significant differences were observed for total bacteria, F. succinogenes, R. albus, and methanogen population among all treatment. Based on these results, T3 could be fed to lambs without deleterious effect on the VFA and N balance

    Analyzing different types of advertising and its influence on customer choice

    Get PDF
    Marketers spend money on a variety of media platforms in order to influence consumer purchasing choice. Every advertisement on every media platform has a unique composition that engages the customers in a different way depending on the platform. The purpose of this research is to determine five types of advertisement and its influence on consumer purchasing choice at selected retailer stores in Erbil. It is a quantitative approach that is used to analyze data that has been obtained by the researcher. The Manager has circulated the survey to consumers of retailer stores and has gathered responses from those customers. When conducting the current study, the researcher employed a questionnaire in order to gather information. In the first segment, demographic questions were asked, beginning with the customer\u27s gender and marital status and progressing to other inquiries. The second section had questions about the company\u27s products and services. The second part of questionnaire was regarding five types of advertisement as independent factors and consumer purchasing choice at selected retailer stores in Erbil. When it comes to the sampling process, it will be a random sampling method, which means that almost all consumers at retailer stores in Erbil will have equal odds of being picked for the findings revealed that all five advertisements will have positive and significant influence on consumer purchasing choice at selected retailer stores, however, it was found that online advertising is the most effective and efficient among all five advertisements to bring consumer attentions while making decision in selecting certain brand or a product at their daily, weekly and monthly shopping at retailer stores in Erbil. The study recommended that management of firms in retail stores should consider it a requirement to adequately market their products, since doing so will provide them a competitive advantage over their competitor

    Customizable, engineered substrates for rapid screening of cellular cues

    Get PDF
    Biophysical cues robustly direct cell responses and are thus important tools for in vitro and translational biomedical applications. High throughput platforms exploring substrates with varying physical properties are therefore valuable. However, currently existing platforms are limited in throughput, the biomaterials used, the capability to segregate between different cues and the assessment of dynamic responses. Here we present a multiwell array (3x8) made of a substrate engineered to present topography or rigidity cues welded to a bottomless plate with a 96-well format. Both the patterns on the engineered substrate and the well plate format can be easily customized, permitting systematic and efficient screening of biophysical cues. To demonstrate the broad range of possible biophysical cues examinable, we designed and tested three multiwell arrays to influence cardiomyocyte, chondrocyte and osteoblast function. Using the multiwell array, we were able to measure different cell functionalities using analytical modalities such as live microscopy, qPCR and immunofluorescence. We observed that grooves (5 µm in size) induced less variation in contractile function of cardiomyocytes. Compared to unpatterned plastic, nanopillars with 127 nm height, 100 nm diameter and 300 nm pitch enhanced matrix deposition, chondrogenic gene expression and chondrogenic maintenance. High aspect ratio pillars with an elastic shear modulus of 16 kPa mimicking the matrix found in early stages of bone development improved osteogenic gene expression compared to stiff plastic. We envisage that our bespoke multiwell array will accelerate the discovery of relevant biophysical cues through improved throughput and variety

    Antidiabetic potential of Moringa oleifera Lam. leaf extract in type 2 diabetic rats, and its mechanism of action

    Get PDF
    Purpose: To explore the antidiabetic potential of Moringa oleifera leaf extract in type 2 diabetic rats, and the underlying mechanisms.Methods: Streptozotocin (STZ) at a dose of 40 mg/kg was given to high fat diet (HFD)- fed rats to induce type 2 diabetes. M. oleifera leaf extract at doses 100, 200 and 400 mg/kg were given to 3 groups of type 2 diabetic rats. The area under curve (AUC) of glucose and homeostasis model assessment of insulin resistance (HOMA-R) were calculated using appropriate formulas, whereas levels of glucose,insulin, peroxisome proliferator activated receptor-γ (PPARγ, dipeptidyl peptidase-IV (DPP-IV) and inflammatory cytokines (IL-6, IL-1β and TNFα) were assayed using ELISA kits.Results: The leaf extract of M. oleifera significantly reduced the levels of glucose, insulin and cytokines in treated type 2 diabetic groups (p < 0.05). DC group had significantly increased AUC for glucose, whereas the extract-treated groups showed significant  decrease in glucose AUC. There was significant decrease in insulin sensitivity parameters, as indicated by increase in HOMA-R and decrease in PPARγ levels in the DC group (p < 0.05). However, treatment with the M. oleifera extract reversed this trend via marked decrease in HOMA-R level and significant rise in PPARγ level. In contrast, the extract had no effect on DPP-IV concentration in diabetic treated groups (p < 0.05).Conclusion: These results indicate that M. oleifera leaf extract mitigates hyperglycemia in type 2 DM by modulating hyperinsulinemia, PPARγ and inflammatory cytokines. Thus, the extract is a potential source of drug for the management of type 2 DM. Keywords: Moringa oleifera, Diabetes mellitus, Streptozotocin, Peroxisome proliferator activated receptor-γ, Dipeptidyl peptidase I

    Effects of corn supplementation on the antioxidant activity, selected minerals, and gene expression of selenoprotein and metallothionein in serum, liver, and kidney of sheep-fed palm kernel cake: urea-treated rice straw diets

    Get PDF
    This study aimed to determine influence of corn inclusion on glutathion peroxidase (GPx) activity, selected minerals concentration, and gene expression in sheep-fed palm kernel cake (PKC) and urea-treated rice straw. Twenty-seven of Dorper sheep were divided into three groups and fed a basal diet of (20% rice straw and 80% concentrate) with addition of ground corn at either 0% (T1), 5% (T2), or 10% (T3), respectively. After 120 days feeding trial, all animals were slaughtered and tissue samples of kidney, liver, and muscles were taken for enzyme and mineral analyses. The results showed that Cu concentration in the liver was lower treatment T3 compared to the control and T2. The serum activity of GPx was higher in T2 than in T3 at day 120 of experiment. Serum malondialdehyde (MDA) concentrations decreased at day 80 in sheep on T3, whereas MDA of liver increased linearly with increasing corn supplementation. The qRT-PCR analyses revealed significant up-regulation of ATP7A and MIa genes in T3, while hepatic Cu/Zn SOD, GPx1, and GPx4 mRNA showed a higher expression in lamb hepatocytes in T3 compared to those on T1. Present study results suggest that feeding PKC as basal diet can increase antioxidant activity, but cause liver dysfunction in sheep. Inclusion corn was found to regulate transcriptional levels of the GPx family and metallothionein genes. These genes may play a role in the antioxidant protection response and reduce incidence of toxicity associated with Cu

    Occupational stress in the construction industry:a bibliometric-qualitative analysis of literature and future research directions

    Get PDF
    Purpose: Given the growing concern about employees' well-being, numerous researchers have investigated the causes and effects of occupational stress. However, a review study on identifying existing research topics and gaps is still deficient in the extant literature. To fill this gap, this review study aims to present a bibliometric and science mapping approach to review the state-of-the-art journal articles published on occupational stress in the construction industry. Design/methodology/approach: A three-fold comprehensive review approach consisting of bibliometric review, scientometric analysis and in-depth qualitative discussion was employed to review 80 journal articles in Scopus. Findings: Through qualitative discussions, mainstream research topics were summarized, research gaps were identified and future research directions were proposed as follows: versatile stressors and stress model; an extended subgroup of factors in safety behavior; adaptation of multiple biosensors and bio-feedbacks; evaluation and comparison of organizational stress interventions; and incorporation of artificial intelligence and smart technologies into occupational stress management in construction. Originality/value: The findings of this review study present a well-rounded framework to identify the research gaps in this field to advance research in the academic community and enhance employees' well-being in construction

    Antihypertensive potential of Brassica rapa leaves: An in vitro and in silico approach

    Get PDF
    Aim: Plants contain many essential constituents and their optimization can result in the discovery of new medicines. One such plant is Brassica rapa that is commonly used as a vegetable to fulfill daily food requirements worldwide. This study intends to screen the phytochemicals, antihypertensive potential, GC-MS, and in silico analysis of the leaves of Brassica rapa. Methods: Powdered leaves were subjected to proximate analysis followed by estimation of primary metabolites. Extracts were obtained by hot and cold extraction and investigated for secondary metabolites. All crude extracts were screened for their antihypertensive potential using an angiotensin-converting enzyme (ACE) inhibition assay. GC-MS analysis was carried out to standardize the extract, and an antihypertensive metabolite was confirmed using an in silico approach. Results: Physicochemical evaluation resulted in moisture content (9.10% ± 0.1), total ash value (18.10% ± 0.6), and extractive values (water 9.46% ± 0.5 and alcohol soluble 4.99% ± 0.1), while phytochemical investigation revealed primary metabolites (total proteins 11.90 mg/g ± 0.9; total fats 3.48 mg/g ± 0.5; and total carbohydrates 57.45 mg/g ± 1.2). Methanol extract showed the highest number of secondary metabolites including polyphenols 93.63 mg/g ± 0.6; flavonoids 259.13 mg/g ± 0.6; and polysaccharides 56.63 mg/g ± 1.4, while water extract (70 mg/g ± 2) was rich in glycosaponins. Methanol extract showed the highest antihypertensive potential by inhibiting ACE (79.39%) amongst all extracts, compared to the standard drug captopril, which inhibited 85.81%. Standardization of methanol extract via GC-MS analysis revealed potent phytoconstituents, and a molecular docking study confirmed that oleic acid is the main antihypertensive metabolite. Conclusion: We conclude that leaves of Brassica rapa can successfully lower hypertension by inhibiting ACE, however; in vivo investigations are required to confirm this antihypertensive activity.Open access funding is provided by the Qatar National Librar

    A Meta-Analysis on Clinical Outcomes of Ceftolozane versus Piperacillin in Combination with Tazobactam in Patients with Complicated Urinary Tract Infections

    Get PDF
    Objective. To evaluate efficacy and adverse events of ceftolozane/tazobactam in complicated UTI including acute pyelonephritis. Method. Databases that include PubMed, Embase, Scopus, and TRIP were searched. All randomized controlled trials and cohort studies were considered for the study. Statistical analysis was done using a fixed effects model, and results were expressed in proportion for dichotomous data and risk ratio for continuous data with 95% confidence intervals (CI). Results. A clinical cure of ceftolozane/tazobactam was found to be 92% with 95% CI of 90-94 while that of piperacillin/tazobactam was only 78% (95% CI, 74-82) in patients with complicated UTI. Microbiological eradication was still higher in the ceftolozane/tazobactam group (83%, 95% CI 81-88) when compared with piperacillin/tazobactam (63% 95% CI, 58.77-65.2). Ceftolozane/tazobactam was more effective in the treatment of complicated urinary tract infections other than acute pyelonephritis as compared to piperacillin/tazobactam (RR=1.21, 95% CI, 1.07-1.23). Serious adverse events were found comparable in both groups (RR=1.15, 95% CI, 0.64-2.09). Conclusion. The analysis showed that ceftolozane/tazobactam has better clinical outcomes including cure rates and low resistance for the treatment of complicated urinary tract infection
    corecore