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51.
Ashraf A. Wani Alamgir A. Dar Ishrat Jan Malik Mukhtar Khurshid A. Sofi G. I. Hassan Javid A. Sofi 《Biomedical chromatography : BMC》2022,36(4):e5335
Herein we report a novel, accurate and cost-effective gas chromatography method for the determination of average deposits of profenofos on green pea and cucumber following good agricultural practices. Additionally the risk assessment, dissipation and waiting period for profenofos were determined. The average initial deposits (2 h after spraying) of profenofos in/on green pea and cucumber were 3.41 and 3.62 mg kg−1 respectively following two applications at a 10 day interval of profenofos 50EC formulation. Profenofos residues on both of the substrates were below the detection limit of 0.05 mg kg−1 after 20 days at the recommended dosage. For risk assessment studies, the 20th day will be safe for consumers for consumption of green peas. The gas chromatography method was validated according to the SANTE guidelines using the various analytical parameters: linearity, accuracy, detection and quantification limits. The developed method is simple, selective and repeatable and can be extended for profenofos-based standardization of pesticide formulations for green pea/cucumber and their use as pesticides. 相似文献
52.
Arslan Iftikhar Rimsha Nausheen Humaira Muzaffar Muhammad Ahsan Naeem Muhammad Farooq Mohsin Khurshid Ahmad Almatroudi Faris Alrumaihi Khaled S. Allemailem Haseeb Anwar 《Molecules (Basel, Switzerland)》2022,27(10)
Honey is the principal premier product of beekeeping familiar to Homo for centuries. In every geological era and culture, evidence can be traced to the potential usefulness of honey in several ailments. With the advent of recent scientific approaches, honey has been proclaimed as a potent complementary and alternative medicine for the management and treatment of several maladies including various neurological disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and multiple sclerosis, etc. In the literature archive, oxidative stress and the deprivation of antioxidants are believed to be the paramount cause of many of these neuropathies. Since different types of honey are abundant with certain antioxidants, primarily in the form of diverse polyphenols, honey is undoubtedly a strong pharmaceutic candidate against multiple neurological diseases. In this review, we have indexed and comprehended the involved mechanisms of various constituent polyphenols including different phenolic acids, flavonoids, and other phytochemicals that manifest multiple antioxidant effects in various neurological disorders. All these mechanistic interpretations of the nutritious components of honey explain and justify the potential recommendation of sweet nectar in ameliorating the burden of neurological disorders that have significantly increased across the world in the last few decades. 相似文献
53.
Anna Avetisyan Marina Markaryan Dinesh Rokaya Marcos Roberto Tovani-Palone Muhammad Sohail Zafar Zohaib Khurshid Anna Vardanyan Artak Heboyan 《Molecules (Basel, Switzerland)》2021,26(5)
The objective of the present study was to investigate the effects of various types of fixed prostheses on periodontal tissues and explore the association of gingival biotype and gum recession in relation to prosthesis types. The study participants (N = 95) were divided into three groups based on the type of dental prosthesis: Group-I: cobalt-chrome (Co-Cr) ceramic prosthesis fabricated by the conventional method (n = 35); Group-II: consisted of patients with Co-Cr ceramic prostheses fabricated by a computer-aided design and computer aided manufacturing (CAD/CAM) technique (n = 30); and Group-III: zirconia-based prostheses fabricated by the CAD/CAM technique (n = 30). Following the use of prostheses, periodontal examinations were performed using the Community Periodontal Index (CPI) and Modified Approximal Plaque Index (MAPI). In addition, the gingival biotype was examined using a probe transparency method. The Statistical Package for the Social Sciences (SPSS), Version 20 (IBM Company, Chicago, IL, USA), was used to analyze the results, and the significance level was set at p = 0.05. It showed the MAPI results after the use of prosthetic rehabilitation for 12 months of periodontitis in 87.9% ± 15.4 of patients in Group-I, in 80.6% ± 17.97 in those in Group-II, and in 62.5% ± 21.4 in those in Group-III (p < 0.01). The CPI index results indicated a high prevalence of periodontal disease in all groups. The number of people with healthy periodontium constituted 17.1% of patients in Group-I, 24.2% in Group-II, and 37.1% in Group-III. Our study concluded that prosthetic treatment with periodontal diseases showed better outcomes while using dental prostheses fabricated by the CAD/CAM technique compared to the conventionally fabricated dental prostheses. The thin gingival biotype is more often associated with gingival recession than the thick biotype. 相似文献
54.
Amna Iftikhar Umaima Zafar Waqar Ahmed Muhammad Asim Shabbir Aysha Sameen Amna Sahar Zuhaib F. Bhat Przemysaw ukasz Kowalczewski Maciej Jarzbski Rana Muhammad Aadil 《Molecules (Basel, Switzerland)》2021,26(24)
Hemp (Cannabis sativa L.) is a herbaceous anemophilous plant that belongs to the Cannabinaceae family. The cannabis seed (hemp) has long been utilized as a food source and is commercially important as an edible oil source. In this review, the positive and negative health effects of cannabis, the relationship between cannabis and various diseases, and the use of cannabis in various food products have been discussed. In addition, the scientific literature on the potential use of cannabis and its derivatives as a dietary supplement for the prevention and treatment of inflammatory and chronic degenerative diseases in animals and humans has been reviewed. Cannabis is being developed as a key ingredient in a variety of food items, including bakery, confectionery, beverages, dairy, fruits, vegetables, and meat. Hemp seeds are high in readily digestible proteins, lipids, polyunsaturated fatty acids (PUFA), insoluble fiber, carbs, and favorable omega-6 PUFA acid to omega-3 PUFA ratio and have high nutritional value. The antioxidants of cannabis, such as polyphenols, help with anxiety, oxidative stress, and the risk of chronic illnesses, including cancer, neurological disorders, digestive problems, and skin diseases. Cannabis has been shown to have negative health impacts on the respiratory system, driving, and psychomotor functions, and the reproductive system. Overall, the purpose of this research is to stimulate more in-depth research on cannabis’s adaptation in various foods and for the treatment of chronic illnesses. 相似文献
55.
M. M. Kamal Ali Z. Abu Zuhri Amna A. O. Nasser 《Fresenius' Journal of Analytical Chemistry》1996,356(8):500-503
The redox behaviour of adsorbed species of 2,4,6-tri(2′-pyridyl)-1,3-5-triazine (TPTZ) at the surface of a mercury electrode
was examined using cycling voltammetry. Based on the adsorption and accumulation of TPTZ at the charged mercury surface cathodic
adsorptive stripping voltammetry (CSV) is applied for the trace determination of TPTZ using a differential pulse (DP) technique.
Experimental and operational parameters for the quantitative analysis of TPTZ are optimized and the detection limit was found
to be 3×10−9 mol/l. The effect of some interferences, e.g. organic compounds, cations and anions, are investigated. 相似文献
56.
Efficient and convenient synthesis of coumarin derivatives was accomplished via reactions of 2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarbothioamide with some carbon electrophiles, e.g. maleic anhydride, dimethyl acetylenedicarboxylate, 1,2-dichloroethane, 3′-nitro-w-bromoacetophenone, N-(4-acetylphenyl)-2-chloroacetamide, ethyl cyanoacetate/3-chlorobenzaldehyde and acetylacetone to construct some N-heterocycles such as thiazolidine, thiazole, pyrimidine and pyrazolone derivatives. The structures of all synthesized products were substantiated from their analytical and spectral data. The antioxidant activities of the synthesized compounds were examined. 相似文献
57.
Ayman Yousef Nasser A.M. Barakat Touseef Amna Afeesh R. Unnithan Salem S. Al-Deyab Hak Yong Kim 《Journal of luminescence》2012,132(7):1668-1677
Among the various nanostructural morphologies, nanofibers have a distinct interest due to the long axial ratio which strongly modifies the photocatalytic activity. In this work, study of the effect of CdO-doping on the photoluminescence properties of ZnO nanofibers was carried out. Nanofibers composed of the two oxides (ZnO and CdO) were prepared using facile, effective, simple and high yield technique; electrospinning. Typically, a sol–gel consisting of poly(vinyl alcohol), cadmium acetate and zinc acetate was electrospun. Calcination of the produced nanofibers in air did not affect the nanofibrous morphology and led to produce ZnO/CdO alloy nanofibers. Interestingly, variation of Zn to Cd ratio in the original electrospun solution did not influence the morphology, so nanofibers having CdO of 39.4, 56.5 and 72.2 wt% could be prepared. Optical properties study indicated that addition of CdO to ZnO decreases the band gap and consequently the introduced nanofibers can be utilized as photocatalyst under a visible light radiation. Moreover, the results indicated that increasing the CdO content causes to increase the solid solubility. Accordingly, the low content CdO nanofibers (39.4 wt%) reveal two band gaps in the PL spectra. Consequently, these nanofibers have the best photocatalytic activity among the prepared samples; the methylene blue dye was completely eliminated within 4.5 h. However, full dye degradation was obtained at relatively longer times when the other formulations were utilized. Beside the simplicity and low cost aspects in the proposed preparation strategy, utilizing the solar radiation as activation energy to initiate the photoreactions might recommend the introduced nanofibers to be exploited as photocatalyts in the field of waste water treatment. 相似文献
58.
A. Khurshid S. Firdous L. Ahmat J. Ferraria J. D. Vollet-Filho C. Kurachi V. S. Bagneto M. Nawaz M. Ikram M. Ahmad 《Laser Physics》2012,22(1):317-321
Up-regulation of stress-activated proteins in cancer cells plays a protective role against photodynamic induced apoptosis. Post photodynamic therapy extracted normal rat liver tissue usually shows a fraction of surviving cells, the photodynamic resistant cells, residing in the necrotic region. To treat these photo-dynamic resistant cells a technique has been proposed based on fractionated drug administration of diluted photosensitizer, keeping the net concentration (5 mg/kg) constant, and subsequently varying drug light interval (DLI). Flourescence measurements were made for the presence of photosensitizer in a tissue. For qualitative analysis both histological and morphological studies were made. Although preliminary aim of this approach was not achieved but there were some interesting observation made i.e. for higher dilution of photosensitizer there was a sharp boundary between necrotic and normal portion of tissue. An increase in the absorption coefficient (α) from 2.7 → 2.9 was observed as photosensitizer was diluted while the corresponding threshold dose (D th) persistently decreases from (0.10 → 0.02) J/cm2 when irradiated with a 635 nm laser fluence of 150 J/cm2. 相似文献
59.
Khurshid Ahmad Mir 《Mathematica Slovaca》2011,61(4):657-664
In this paper, a size-biased Consul distribution (SBCOND) is defined. Recurrence relations for central moments and the moments
about origin are obtained. Different estimation methods for the parameters of the model are discussed. A comparative analysis
is done among the three different estimation methods and the proposed model is compared with the generalized logarithmic series
distribution (GLSD) and simple Consul distribution. 相似文献
60.
Ghulam Bary Muhmmad Imran Jamil Muhammad Arslan Lubna Ghani Waqar Ahmed Haseen Ahmad Gohar Zaman Khurshid Ayub Muhammad Sajid Riaz Ahmad Duohui Huang Futi Liu Yue Wang 《Journal of Saudi Chemical Society》2021,25(7):101260
Alkene is an attractive substrate for chemists due to its easy availability and reactivity towards large number of reactants affording diverse range of organic compounds. It reacts under ionic and free radical mechanisms including single electron transfer (SET). In this review, strategies used for C–C and C-heteroatom functionalization of alkene has been discussed with emphasis on the regio, stereoselectivity, mechanistic detail and sustainability aspects. These strategies mainly follow the free radical mechanism, and the highly reactive carbon radicals show uncontrollable regio- and stereoselectivities. Thus these strategies still need to be focused; especially in the asymmetric versions. The regio- and stereoselectivities of functionalization of alkenes have been highlighted and debated. In addition, the hazardous reagents such as Cl2, Br2 I2, CO, peroxides, and benzene have also been discussed with the emphasis on their impact on the environment. Their plausible green alternatives have also been suggested, such as MX as halogen replacement; CO surrogates (formaldehyde etc.); sustainable aromatic solvents as benzene replacement. The non-green strategies relying on pre-formed silyl hydride and their green alternative strategies such as transfer hydrogenations have also been indicated. The applications of the functionalization of alkenes for the total synthesis of bioactive compounds have also been discussed in detail. In addition, future perspectives are also highlighted for further developments in the functionalization of alkenes. 相似文献