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| 1 | Genesis of tuff interval and its uranium enrichment in Upper Triassic of Ordos Basin, NW China显示文摘Recently measured high gamma ray values in the Yanchang Formation of the Upper Triassic in the Ordos Basin have added an interesting and controversial twist to the study of the formation’s uranium enrichment and genesis.High uranium and thorium contents in the tuffaceous layer cause high gamma ray values in the Yanchang Formation.Petrographic studies,major elements,rare earth elements(REEs),and trace elements have been systematically analyzed to determine the composition,geochemical environment,and diagenetic processes of the layer.The observed color of the tuffaceous layer in the study area varies from yellow to yellowish brown.The tuff consists of matrix supported with sub-rounded to sub-angular lithic fragments.These lithic fragments probably derived from pre-existing rocks and incorporated into the tuffaceous layer during volcanic eruption.Quartz,plagioclase,and biotite were observed in well to poorly sorted form,in addition to framboidal pyrite and organic laminae.Measured ratios of SiO_2/Al_2O_3 ranged from 3.277 to 6.105 with an average of 3.738.The ratio of TiO_2/Al_2O_3 varied from 0.037 to 0.201 with an average of 0.061,indicating that the sediments of the tuffaceous layer originated from an intermediate magma.REE distribution patterns show sharp negative Eu anomalies,indicating a reducing environment,which is suitable for uranium deposition.A reducing environment was confirmed by black shale in the base of the Yanchang Formation.Such black shale has high organic matter content that can take kerogene from mudstone and provide a reducing environment for uranium enrichment in the tuffaceous layer.Moreover,negative Eu anomalies and the REE patterns indicate a subduction-related volcanic arc environment as the magma source of the tuffaceous layers.High values of Rb,Ba,and Sr might be the result of fluid phase activities;low values of Hf and Eu indicate the involvement of crustal material during diagenesis of the tuff.Discrimination diagrams(Th/Yb vs Ta/Yb,Th/Hf vs Ta/Hf)suggest an active continental margin as the tectonic setting of source volcanoes.Plots of Nb versus Y,Rb versus Y+Nb,TiO_2 versus Zr,and Th/Yb versus Nb/Yb of the tuffaceous content point to calc-alkaline continental arc-related magmatism.We concluded that uranium enrichment in the tuffaceous layer was supported by oxidation–reduction. | Shamim Akhtar Nosheen Sahir Xiaoyong Yang | 2018 | Acta Geochimica2018，37，1： | 4 |
| 2 | Geochemistry of sedimentary rocks from Permian–Triassic boundary sections of Tethys Himalaya: implications for paleo-weathering, provenance, and tectonic setting显示文摘The geochemical characteristics of two sections—the Permian–Triassic boundary(PTB) Guryul Ravine section, Kashmir Valley, Jammu and Kashmir,India; and the Attargoo section, Spiti Valley, Himachal Pradesh, India—have been studied in the context of provenance, paleo-weathering, and plate tectonic setting.These sections represent the siliciclastic sedimentary sequence from the Tethys Himalaya. The PTB siliciclastic sedimentary sequence in these regions primarily consists of sandstones and shales with variable thickness. Present studied sandstones and shales of both sections had chemical index of alteration values between 65 and 74; such values reveal low-to-moderate degree of chemical weathering. The chemical index of weathering in studied samples ranged from 71 to 94, suggesting a minor K-metasomatism effect on these samples. Plagioclase index of alteration in studied sections ranged from 68 to 92, indicating a moderate degree of weathering of plagioclase feldspars. The provenance discriminant function diagram suggests that the detritus involved in the formation of present studied siliciclastic sedimentary rocks fall in quartzose sedimentary and felsic igneous provenances. These sediments were deposited in a passive continental margin plate tectonic setting according to their location on a Si_2 O versus K_2O/Na_2 O tectonic setting diagram. | Akhtar R.Mir V.Balaram Javid A.Ganai Shamim A.Dar A.Keshav Krishna | 2016 | Acta Geochimica2016，35，4： | 3 |
| 3 | Zircon U–Pb ages, Hf–O isotopes and trace elements of Mesozoic high Sr/Y porphyries from Ningzhen, eastern China: Constraints on their petrogenesis, tectonic implications and Cu mineralization显示文摘 | Fangyue Wang Sheng-Ao Liu Shuguang Li Shamim Akhtar Yongsheng He | 2014 | LITHOS2014，，： | 1 |
| 4 | Role of sawdust in the removal of copper(II) from industrial wastes显示文摘 | Mohammed Ajmal Akhtar Hussain Khan Shamim Ahmad Anees Ahmad | 1998 | Water Research1998，，10： | 1 |
| 5 | Role of sawdust in the removal of copper(Ⅱ)from industrial wastes显示文摘 | MOHAMMED A M AKHTAR H K SHAMIM A | 1998 | Water Research1998，32，10： | 1 |
| 6 | Mortality characteristics during the two waves of COVID-19 in India:A retrospective observational study显示文摘Objective:To evaluate patient demographic characteristics and risk factors for mortality during the first and the second wave among COVID-19 patients in a tertiary care hospital of India.Methods:Data were taken from the hospital’s electronic system for COVID-19 patients from August 2020 to December 2020,and the second from January 2021 to May 2021.The mortality rate,demographic and clinical characteristics,laboratory profile,and reasons for the death of the two waves were retrieved and compared,and the risk factors of the two waves were determined.Results:In the first wave,1177 COVID-19 cases visited the hospital and 96(8.2%)died.In comparison,the death rate in the second wave was significantly higher(244/2038,12.0%)(P<0.001).No significant difference in age[60(50-69)vs.60.5(53-70),P=0.11]or gender(P=0.34)was observed between the two waves.Compared to the first wave.there were significantly more cases with fever,cough,weakness,loss of taste and smell,and sore throat during the second wave(P<0.05),but significantly fewer cases with kidney disease(6.6%vs.13.5%,P=0.038)and diabetes mellitus(35.7%vs.50.0%,P=0.015).Besides,during the second wave,more patients had abnormal X-ray findings,higher levels of lymphocytes and serum ferritin(P<0.05).In addition,there were significant differences in the rate of death cases with acidosis,septic shock,acute kidney injury,diabetes mellitus,cardiovascular events,hypothyroidism(P<0.05).Multivariate regression showed that during the first wave,age(OR:1.10;95%CI:1.02-1.21),diabetes mellitus(OR:3.16;95%CI:2.08-3.53),and abnormal X-ray(2.67;95%CI:2.32-2.87)were significant independent risk factors of mortality;while in the second wave,age(OR:1.13;95%CI:1.12-1.28),diabetes mellitus(OR:8.98;95%CI:1.79-45.67),abnormal X-ray(OR:12.83;95%CI:2.32-54.76),high D-dimer(OR:10.89;95%CI:1.56-134.53),and high IL-6(OR:7.89;95%CI:1.18-47.82)were significant independent risk factors of mortality.Conclusion:Overall mortality and incidence of severe diseases are higher in the second wave than the first wave.Demographic characteristics,co-morbidities,and laboratory inflammatory parameters,especially D-dimer and IL-6,are significant risk facors of mortality during the COVID-19 pandemic. | Nalini Ramesh Humaney Shilpa Sachin Kuthe Shamim Akhtar Vivek K Pande | 2022 | Journal of Acute Disease2022，11，2： | 1 |
| 7 | Role of sawdust in the removal of copper( Ⅱ ) from industrial wastes 显示文摘 | Mohammed A Akhtar H K Shamim A | 1998 | Water Research1998，32，： | 1 |
| 8 | Role of sawdust in the removal of copper(II) from industrial wastes显示文摘 | Mohammed Ajmal Akhtar Hussain Khan Shamim Ahmad Anees Ahmad | 1998 | Water Research1998，，10： | 1 |
| 9 | 鄂尔多斯盆地上三叠统凝灰岩中的铀富集显示文摘 | SHAMIM Akhtar 古黄玲 杨晓勇 | 2016 | 地质论评2016，62，B11： | 1 |
| 10 | Role of sawdust in the removal of copper ( Ⅱ )from industrial wastes显示文摘 | Mohammed A M Akhtar H K Shamim A | 1998 | Water Research1998，32，10： | 1 |
| 11 | Detection of QTL(quantitative trait loci) associated with wood density by evaluating genetic structure and linkage disequilibrium of teak显示文摘To find the quantitative trait loci associated with wood density in teak(Tectona grandis L.f.), 21 co-dominant markers including 13 site specific recombinase and 8 EST-based co-dominant markers designed from lignin biosynthesis genes were applied to 174 teak plus tree clones at the National Germplasm Bank, Chandrapur,India. The germplasm bank exhibited 10.6% coefficient of variation for wood densities with 84.5 ± 31.3 genetic polymorphism(%). The highly panmictic set of genotypes(FST= 0.035 ± 0.004) harbored 96.47 ± 0.40 genetic variability(%). The average allelic frequency of the 21 codominant markers was 0.65 ± 0.11 with 12.9% pairs of loci in significant LD(p\0.05, R^2 values [ 0.1), confirming their suitability for a strong marker-trait association study. The marker CCoAMT-1 was significantly(p\0.01) associated with wood density showing stability by both GLM and MLM models and explained 4.3% of the phenotypic effect. The marker from the EST representing CCoAMT can be further developed for gene-assisted selection of elite genotypes of teak with greater wood density. Therefore, we believe that the report will help accelerate the genetic improvement and advance the breeding program of the species. | Vivek Vaishnav Shamim Akhtar Ansari | 2019 | Journal of Forestry Research2019，30，6： | 1 |
| 12 | Role of sawdust in the removal of copper( I1 ) from industrial wastes显示文摘 | Mohammed A M Akhtar H K Shamim A | 1998 | Water Research1998，32，10： | 1 |
| 13 | Impact of numerous larval diets on the biology of pink bollworm Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)under laboratory conditions显示文摘Background Pink bollworm,Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)has become a poten-tial pest of cotton by causing substantial yield losses around the world including Pakistan.Keeping in view the facts like limited research investigations,unavailability,and high cost of artificial diet’s constituents and their premixes,the present research investigations on the dietary aspect of P.gossypiella were conducted.The larvae of P.gossypiella were reared on different diets that were prepared using indigenous elements.The standard/laboratory diet com-prised of wheat germ meal 34.5 g,casein 30.0 g,agar–agar 20.0 g,sucrose 10.0 g,brewer’s yeast 5.0 g,α-cellulose 1.0 g,potassium-sorbate1.5 g,niplagin 0.5 g,decavitamin 0.01 g,choline-chloride 0.06 g,maize-oil 3.30 g,honey 2.0 g,and water 730.0 mL.Alternatives to cotton bolls and wheat germ meal were okra seed sprouts,okra fruit,cottonseed meal,and okra seed meals,which were included in the study to introduce an efficient and economic mass-rearing system.Results The larval development completed in 19.68d±0.05 d with a weight of 20.18mg±0.20 mg at the fourth instar fed on the cottonseed meal-based diet instead of wheat germ meal based diet.On the same diet,84.00%±4.00%,17.24 mg±0.03 mg,and 7.76d±0.06 d were recorded as pupae formation,pupal weight,and pupal duration,respectively.Adult emergence,76.00%±1.00%was recorded from pupae collected from larvae raised on cottonseed meal-based diet.These male and female moths lived for 40.25d±0.10 d,and 44.34d±0.11 d,respectively.Females deposited 21.28±0.04 eggs per day with the viability of 65.78%±0.14%.The larval mortal-ity at the fourth instar was 37.20%±1.36%and malformed pupation of 12.00%±1.41%was recorded.Replacement of wheat germ meal with that of local meals(cottonseed and okra seed)in the standard laboratory diet has saved 463.80 to 467.10 PKR with 1.62 to 1.63 cost economic returns,respectively.Conclusion This research is of novel nature as it provides a concise and workable system for the economic and suc-cessful rearing of P.gossypiella under laboratory conditions. | AKHTAR Shamim ARIF Muhammad Jalal GOGI Muhammad Dildar HAQ Imran-ul | 2024 | Journal of Cotton Research2024，7，1： | 0 |
| 14 | Biochemical investigations during in vitro adventitious shoot regeneration in leaflet explants from nodal segments of a mature Albizia procera tree显示文摘The in vitro adventitious shoot differentiation in leaflet explants of an adult tree differed from that of leaflet explants of seedlings of Albizia procera(Roxb.)Benth. reported previously elsewhere. The leaflet explants from an adult tree passed through an initial callus phase for30 days on MS medium supplemented with 3 % sucrose,2.5 l M 2,4-D followed by a subsequent adventitious shoot differentiation phase for another 30 days on half MS medium supplemented with 0.25 l M each of BA and IBA.The regeneration rate of in vitro adventitious shoots in explants from the adult tree, i.e.1.66 shoots/callus, was lower than that from seedlings, i.e. [10 shoots/callus,which was reported elsewhere. Correspondingly, the activities of nitrate reductase and peroxidase, and endogenous phenol content remained very low during in vitro adventitious shoot differentiation in leaflet explants of an adult tree possibly due to lower availability of competent stem(juvenile) cells for the process. | Ekta Rai Sulochna Bouddha Shamim Akhtar Ansari | 2016 | Journal of Forestry Research2016，27，3： | 0 |
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