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31.
Mohammed S. Alqahtani Mohamed Abbas Mohammed Abdulmuqeet Abdullah S. Alqahtani Mohammad Y. Alshahrani Abdullah Alsabaani Murugan Ramalingam 《Materials》2022,15(14)
The COVID-19 pandemic has the tendency to affect various organizational paradigm alterations, which civilization hasyet to fully comprehend. Personal to professional, individual to corporate, and across most industries, the spectrum of transformations is vast. Economically, the globe has never been more intertwined, and it has never been subjected to such widespread disruption. While many people have felt and acknowledged the pandemic’s short-term repercussions, the resultant paradigm alterations will certainly have long-term consequences with an unknown range and severity. This review paper aims at acknowledging various approaches for the prevention, detection, and diagnosis of the SARS-CoV-2 virus using nanomaterials as a base material. A nanostructure is a material classification based on dimensionality, in proportion to the characteristic diameter and surface area. Nanoparticles, quantum dots, nanowires (NW), carbon nanotubes (CNT), thin films, and nanocomposites are some examples of various dimensions, each acting as a single unit, in terms of transport capacities. Top-down and bottom-up techniques are used to fabricate nanomaterials. The large surface-to-volume ratio of nanomaterials allows one to create extremely sensitive charge or field sensors (electrical sensors, chemical sensors, explosives detection, optical sensors, and gas sensing applications). Nanowires have potential applications in information and communication technologies, low-energy lightning, and medical sensors. Carbon nanotubes have the best environmental stability, electrical characteristics, and surface-to-volume ratio of any nanomaterial, making them ideal for bio-sensing applications. Traditional commercially available techniques have focused on clinical manifestations, as well as molecular and serological detection equipment that can identify the SARS-CoV-2 virus. Scientists are expressing a lot of interest in developing a portable and easy-to-use COVID-19 detection tool. Several unique methodologies and approaches are being investigated as feasible advanced systems capable of meeting the demands. This review article attempts to emphasize the pandemic’s aftereffects, utilising the notion of the bullwhip phenomenon’s short-term and long-term effects, and it specifies the use of nanomaterials and nanosensors for detection, prevention, diagnosis, and therapy in connection to the SARS-CoV-2. 相似文献
32.
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
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34.
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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36.
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
37.
Karaer A Mert I Akinsu F Tug M Tefs K Schuster V Mollamahmutoglu L 《The journal of obstetrics and gynaecology research》2007,33(4):581-584
Ligneous inflammation is a rare disease characterized by progressive growth of ligneous plaques on mucosal surfaces. Involvement of the female genital tract is an unusual condition. We present a patient with multifocal ligneous inflammation involving her genital tract, oral mucosa and conjunctiva. Plasminogen functional activity was 18% of normal (reference: 55-145%). Molecular analysis exhibited that her genetic status is homozygous for a combination of three polymorphisms. But no true mutation could be found in all 19 exons of the plasminogen gene. We did not observe any clinical changes, although plasminogen activity has improved in the course of 5 months of oral contraceptive therapy Most gynecologists are unfamiliar with this diagnosis and pathologists with wide experience in gynecology are unaware of this disease. However, the histology of lesions is characteristic and a diagnosis can be made quite easily once it has been considered. 相似文献
38.
IntroductionFemale sexual dysfunction (FSD) is a prevalent sexual health problem that does not spare the women in Malaysia, a nation with a conservative multiethnic society.AimTo investigate the prevalence of FSD and the potential risk factors that may impair sexual function among women at a primary care setting in Malaysia.Main Outcome MeasureThe prevalence, the risk factors, and the main predictors for FSD were measured among these women.MethodsA validated Malay version of the Female Sexual Function Index was used to assess FSD. A total of 230 married women aged 18–70 years participated in this study. The sociodemographic and marital profiles of women who had FSD and those who did not were compared; the risk factors for FSD were determined.ResultsThe majority of the respondents were younger than 50 years old, predominantly Malays, and had a higher academic achievement. The prevalence of FSD in the primary care population was 29.6%. The prevalence of women with lack of orgasms, low sexual arousal, lack of lubrication, sexual dissatisfaction, and sexual pain were 59.1%, 60.9%, 50.4%, 52.2%, and 67.8%, respectively.ConclusionThe risk factors for FSD are older age, Malays, married longer (more than 14 years), having less sexual intercourse (less than 1–2 times a week), having more children, married to an older husband (aged >42 years), and having a higher academic status. Lack of lubrication is found to be the main predictor for FSD in this study. Is lack of lubrication a cause or a complication of FSD? Prospective research is needed in the near future. Sidi H, Puteh SEW, Abdullah N, and Midin M. The prevalence of sexual dysfunction and potential risk factors that may impair sexual function in Malaysian women. 相似文献
39.
Abdullah Alhendal Randa Abd Almoaeen Mohamed Rashad Ali Husain Fouzi Mouffouk Zahoor Ahmad 《RSC advances》2022,12(28):18077
This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. To overcome the inherent shortcomings of the CNTs'' solubility and dispersion in both organic phases and in the sol–gel solution, the outer surface of the CNTs was initially functionalized with carboxylic acid groups and then reacted with both aramid oligomers and 3-aminopropyl triethoxysilane (APTES). The obtained sorbent was characterized by FT-IR, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Using sol–gel chemistry, the functionalized CNTs were coated onto SPME fibers and used in conjunction with GC-MS for the analysis of polycyclic aromatic hydrocarbons (PAHs) in water and soil samples. Excellent repeatability (run-to-run RSD% ∼ 8) and reproducibility (fiber-to-fiber RSD% ∼ 6) were achieved in addition to low LODs (0.10–0.30 ng mL−1) and noticeable recovery%. The present method of sorbent preparation led to enhanced thermal and chemical stabilities, a long sorbent lifetime and good affinity towards PAHs. Moreover, the present sorbent enhanced the extraction capability by more than 30% compared to that of commercially available PDMS counterparts.This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. 相似文献
40.