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51.
Sheraz Ullah Muhammad Izhar Shah Muwaffaq Alqurashi Muhammad Faisal Javed Osama Dawood Fahid Aslam Muhammad Atiq Ur Rehman Tariq Enas E. Hussain 《Materials》2022,15(7)
The consumption of waste materials in the construction sector is a sustainable approach that helps in reducing the environmental pollution and decreases the construction cost. The present research work emphasizes the mechanical properties of bituminous concrete mix prepared with crumb rubber (CR) and waste sugarcane bagasse ash (SCBA). For the preparation of bituminous concrete mix specimens with CR and SCBA, the effective bitumen content was determined using the Marshall Mix design method. A total of 15 bituminous concrete mix specimens with 4%, 4.5%, 5%, 5.5% and 6% of bitumen content were prepared, and the effective bitumen content turned out to be 4.7%. The effect of five different CR samples of 2%, 4%, 6%, 8% and 10% by weight of total mix and SCBA samples of 25%, 50%, 75% and 100% by weight of filler were investigated on the performance of bituminous concrete. A total of 180 samples with different percentages of CR and SCBA were tested for indirect tensile strength (ITS) and Marshall Stability, and the results were compared with conventional bituminous concrete mix. It was observed that the stability values rose with an increase in CR percentage up to 6%, while the flow values rose as the percentage of SCBA increased in the mix. Maximum ITS results were observed at 4% CR and 25% SCBA replacement levels. However, a decrease in stability and ITS result was observed as the percentages of CR and SCBA increased beyond 4% and 25%, respectively. We concluded that the optimum CR and SCBA content of 4% and 25%, respectively, can be effectively used as a sustainable alternative in bituminous concrete mix. 相似文献
52.
Awais Khalid Pervaiz Ahmad Abdulhameed Khan Mayeen Uddin Khandaker Imen Kebaili Md Mottahir Alam Israf Ud Din Saleh Muhammad Zohaib Razzaq Ibad Ur Rehman Habib Ahmad Abbasi Danish Hayat 《RSC advances》2022,12(11):6592
Boron nitride (BN) nanomaterials are rapidly being investigated for potential applications in biomedical sciences due to their exceptional physico-chemical characteristics. However, their safe use demands a thorough understanding of their possible environmental and toxicological effects. The cytotoxicity of boron nitride nanotubes (BNNTs) was explored to see if they could be used in living cell imaging. It was observed that the cytotoxicity of BNNTs is higher in cancer cells (65 and 80%) than in normal cell lines (40 and 60%) for 24 h and 48 h respectively. The influence of multiple experimental parameters such as pH, time, amount of catalyst, and initial dye concentration on percentage degradation efficiency was also examined for both catalyst and dye. The degradation effectiveness decreases (92 to 25%) as the original concentration of dye increases (5–50 ppm) due to a decrease in the availability of adsorption sites. Similarly, the degradation efficiency improves up to 90% as the concentration of catalyst increases (0.01–0.05 g) due to an increase in the adsorption sites. The influence of pH was also investigated, the highest degradation efficiency for MO dye was observed at pH 4. Our results show that lower concentrations of BNNTs can be employed in biomedical applications. Dye degradation properties of BNNTs suggest that it can be a potential candidate as a wastewater and air treatment material.Photocatalytic degradation studies of methyl orange using BNNTs. 相似文献
53.
Aravind Periyasamy Gandhi Soundappan Kathirvel Tanveer Rehman 《Journal of Rural Medicine》2022,17(2):59
Objectives: The coronavirus disease 2019 (COVID-19) pandemic affected routine healthcare services across all spectra, and tuberculosis (TB) care under the National Tuberculosis Elimination Program have been affected the most. However, evidence available at the community level is minimal. The clinical features, care cascade pathway, and treatment outcomes of TB patients pre- and during/post-COVID-19 pandemic lockdown in a rural community health block in northern India were assessed and compared.Materials and Methods: This was a retrospective cohort study that included all patients diagnosed with TB and initiated treatment under programmatic settings between January 1 and June 30, 2020, in a rural TB unit in northern India. The periods from January 1 to March 23 and March 24 to June 30 were marked as pre-lockdown and during/post-lockdown, respectively.Results: A total of 103 patients were diagnosed and treated for TB during the study period. A significantly higher proportion of pulmonary TB cases were reported during/post-lockdown (43, 82.7%) compared to that pre-lockdown (32, 62.7%), and a higher diagnostic delay was noted during/post-lockdown (35, 81.4%). Through adjusted analysis, patients diagnosed during/post-lockdown period (adjusted risk ratio [aRR], 0.85; 95% confidence interval [CI], 0.73–0.98) and previously treated (aRR, 0.77; 95% CI, 0.60–0.995) had significantly lower favorable treatment outcomes.Conclusions: The symptom and disease (pulmonary/extrapulmonary) pattern have changed during/post-lockdown. The care cascade delays are still high among TB patients, irrespective of the lockdown status. Lockdown had a significant adverse impact on the outcomes of TB treatment. 相似文献
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β-Thalassemia (β-thal) is a monogenic disease characterized by mutations on the HBB gene, affecting the production of globin that results in hypochromic and microcytic anemia. The aim of this study was to determine the prevalence of six common β-thal mutations, and their frequency and inheritance pattern in affected populations of North Waziristan Agency, Pakistan. In this study, 130 blood samples from 37 unrelated β-thalassemic families having a minimum of one transfusion-dependent child with β-thal major (β-TM), were retrieved either from the Thalassaemia Centre for Women and Children Hospital Bannu or their home towns situated in Noth Waziristan Agency. All samples were analyzed by the amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) using six allele-specific primers for the presence of the six β-thal mutations common in the Pakistani population. Of the six common mutations, our study demonstrated five HBB mutations comprising HBB: c.27_28insG, HBB: c.92+5G>C, HBB: c.126_129delCTTT, HBB: c.92+1G>T and HBB: c.17_18delCT from the families studied, while mutation HBB: c.47G>A [codon 15 (G>A)] was not detected in any of the studied families. Furthermore, the HBB: c.27_28insG and HBB: c.92+5G>C were noted to be the most common with frequencies of 42.85 and 31.42%, respectively. The findings of the present study may be useful in launching carrier screening and prenatal diagnosis (PND) programs by screening analyzed and other unanalyzed affected families for the possible presence of common mutations through the ARMS-PCR technique that will help to control the disease. 相似文献
56.
Abdul Rehman Franz J. Conraths Carola Sauter‐Louis Jürgen Krücken Ard M. Nijhof 《Transboundary and Emerging Diseases》2019,66(1):526-536
Tick‐borne diseases (TBDs) have a large impact on animal health and the livelihood of livestock owners, particularly in developing countries. Although climatic and ecological conditions in Pakistan may favour the transmission of tick‐borne pathogens (TBPs), only a few systematic studies have been carried out on TBPs and the diseases that they cause in this country. To improve our understanding of the distribution of TBPs, 3,807 ticks were collected from ruminants (n = 369) on 108 livestock farms (semi‐arid zone = 36, arid zone = 72) in Punjab Province. After morphological identification ticks were pooled into 405 pools (Hyalomma anatolicum = 300, Rhipicephalus microplus = 89, Hyalomma dromedarii = 9, Rhipicephalus turanicus = 7) based on their species, locality of collection, and the host. DNA from each pool was screened by a Reverse Line Blot (RLB) hybridization assay for the presence of Anaplasma, Ehrlichia, Rickettsia, Babesia, and Theileria species. DNA from at least one TBP was found in 142 (35.1%) pools. Among the positive pools, 91 (64.1%) had a mixed infection with two or more TBPs, whereas 51 (35.9%) pools were infected with a single TBP. The detected pathogens not only included species that were known to be endemic in Pakistan, such as Theileria annulata (6.7%), Theileria orientalis (3.5%), Anaplasma marginale (5.7%), Anaplasma centrale (2.7%), Anaplasma ovis (1.5%), Babesia bigemina (0.7%), and Babesia bovis (0.2%), but also several TBPs that had not been reported to occur in Pakistan before. This included Ehrlichia minasensis (3.2%), an Anaplasma platys‐like organism (1.2%), Babesia occultans (0.2%), and Rickettsia massiliae (0.2%), as well as two previously uncharacterized species: Ehrlichia sp. Multan (18.0%) and Anaplasma sp. (BL099‐6) (2.22%). The pathogenicity of these novel species remains to be examined. This study shows that a much broader spectrum of TBPs is present in Pakistan than previously thought, including several zoonotic pathogens. 相似文献
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58.
Asad Ur Rehman Khan Muhammad Ramzan Muhammad Faisal Iqbal Muhammad Hafeez Mohammed M. Fadhali Hamoud H. Somaily Muhammad Javid Muhammad Waqas Mukhtar Muhammad Farooq Saleem 《Materials》2022,15(22)
Zinc sulfide (ZnS) thin films with variable structural, optical, electrical, and thermoelectric properties were obtained by changing the source-to-substrate (SSD) distance in the physical-vapor-thermal-coating (PVTC) system. The films crystallized into a zinc-blende cubic structure with (111) preferred orientation. The films had a wide 3.54 eV optical band gap. High-quality homogenous thin films were obtained at 60 mm SSD. The sheet resistance and resistivity of the films decreased from 1011 to 1010 Ω/Sq. and from 106 to 105 Ω-cm, when SSD was increased from 20 mm to 60 mm, respectively. The phase and band gap were also verified by first principles that were in agreement with the experimental results. Thermoelectric characteristics were studied by using the semi-classical Boltzmann transport theory. The high quality, wide band gap, and reduced electrical resistance make ZnS a suitable candidate for the window layer in solar cells. 相似文献
59.
Effect of Vascular Risk Factors and Diseases on Mortality in Individuals with Dementia: A Systematic Review and Meta‐Analysis 下载免费PDF全文
60.