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41.
Hammad Ahmed Shah Moncef L. Nehdi Muhammad Imtiaz Khan Usman Akmal Hisham Alabduljabbar Abdullah Mohamed Muhammad Sheraz 《Materials》2022,15(15)
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete. 相似文献
42.
Selim Kurtoglu Mehmet Emre Atabek Ceyhun Dizdarer Ozgur Pirgon Pinar Isguven Sevil Emek 《Pediatric diabetes》2009,10(6):401-407
Background: Insulin detemir is a basal insulin analog designed to produce a superior pharmacokinetic profile to basal formulations of human insulin. It has shown consistently improved tolerability in comparison to neutral protamine Hagedorn (NPH) insulin in adult cohorts, but there are relatively few publications involving pediatric cohorts. Methods: The efficacy and safety of insulin detemir in children with type 1 diabetes was assessed using data from the Turkish cohort of PREDICTIVE? (a large, multinational, observational) study. The children investigated were using basal–bolus therapy involving NPH insulin or insulin glargine at baseline but were switched to insulin detemir as part of routine clinical care by their physicians. Results: Twelve weeks of treatment with insulin detemir significantly reduced mean hemoglobin A1c (9.7–8.9%, p < 0.001) and mean fasting glucose [185–162 mg/dL (10.3–9 mmol/L), p < 0.01]. Fasting glucose variability was also lower after treatment with insulin detemir than previously (on either NPH or glargine, p < 0.05). The frequencies of total, major and nocturnal hypoglycemic events were significantly reduced with insulin detemir relative to baseline, with an estimated mean of 6.89 fewer events/patient/yr overall (p < 0.001) and 2.6 fewer nocturnal events/patient/yr (p < 0.01). Weight and insulin dose remained relatively unchanged. Conclusions: Twelve weeks of treatment with insulin detemir improved glycemic control and reduced hypoglycemia in children with type 1 diabetes. This improved tolerability might allow further dose titration and therefore additional improvements in glucose control. 相似文献
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Al-Johar D Shinwari N Arif J Al-Sanea N Jabbar AA El-Sayed R Mashhour A Billedo G El-Doush I Al-Saleh I 《Phytotherapy research : PTR》2008,22(10):1311-1323
This study examined the chemopreventive effect of Nigella sativa and some of its antioxidant constituents on a number of colon cancer biomarkers in rats induced with azoxymethane (AOM). Sixty male Sprague-Dawley rats were randomly assigned into ten subgroups: vehicle (1-5) and experimental (6-10). The rats in each group were fed one of the following diets: basal diet, (200 mg/kg) Nigella sativa, (0.2 mg/kg) selenium, (1.2 mg/kg) all-trans-retinol plus (100 mg/kg) DL-alpha-tocopherol and (10 mg/kg) thymoquinone, respectively. Only rats in subgroups 6-10 were injected with AOM (15 mg/kg) once per week for 2 weeks. Both groups were fed their respective diets for 5 weeks. Then they were killed and examined for colonic aberrant crypt foci (ACF). Our result showed that only vitamin supplementation was effective on ACF. Nigella sativa revealed inhibitory effects only on DNA damage (day 34) in the AOM-treated rat group. Alternatively, selenium, thymoquinone and vitamins inhibited the MDA content in the liver. Although the exact mechanisms involved in the protective role of Nigella sativa against the initiation of colon carcinogenesis are not clearly understood, the results suggest that its inhibitory effects might depend on the combined competitive inhibition of various antioxidant constituents of this plant. 相似文献
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Abdallah MA Abdullah HI Kang S Taylor DD Nakajima ST Gercel-Taylor C 《Fertility and sterility》2007,87(4):978-981
We describe our experience of over 300 cycles of preimplantation genetic diagnosis (PGD) and report clinical pregnancy rates (35%-67%) that support using this technology to screen for genetic disorders and chromosomal abnormalities. In clinical practice for over ten years, PGD offers couples the earliest form of genetic screening and may help improve ongoing pregnancy rates in poor-prognosis patients. 相似文献
49.
OBJECTIVE: To investigate the effect of continuous administration of gonadotropin-releasing hormone agonist (GnRHa) during the luteal phase in an intracytoplasmic sperm injection program. STUDY DESIGN: One hundred eighty-one women underwent a down-regulation protocol of GnRHa administered from the 21st day of the preceding cycle. Patients were randomized at initiation of stimulation by a computer-generated list. Group 1 patients (n = 90) were continuously administered GnRHa for 12 days after embryo transfer, while in group 2 patients GnRHa was stopped on the day of human chorionic gonadotropin administration. RESULTS: Demographic parameters, infertility etiologies, number of gonadotropin ampules used, number of mature oocytes recovered, rates of testicular sperm usage, number of embryos transferred, and cycle and transfer cancellation rates were similar in both groups. Clinical pregnancy rates, implantation rates and live birth rates did not show a significant difference. CONCLUSION: Extending GnRHa treatment through the luteal phase appeared not to have a significant impact on pregnancy or implantation rates in intracytoplasmic sperm injection cycles. 相似文献
50.
Macrocephaly describes a head circumference greater than two standard deviations above the mean and is a feature of a number of genetic syndromes. Here we report on two patients with microcephaly, immune deficiency and anemia. In addition, one case had periventricular leukomalacia and the other case had myelinisation delay in periventricular white matter development. These cases may represent a distinct new syndrome. 相似文献