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Biosynthesis of polyhydroxyalkanoates from styrene by Enterobacter spp. isolated from polluted environment

Frontiers in Biology 2017年第3期12卷 210-218页

作者： Arooj arshad Bisma Ashraf Iftikhar Ali Nazia Jamil Department of Microbiology and Molecular Genetics University of the Punjab Quaid-e-Azam Campus Lahore-54590 Pakistan

BACKGROUND： Styrene and its metabolites are known to have serious adverse effects on human health and hence, strategies to prevent its release, eradicate it from the environment, and understand its route of degradation are being considered. METHODS： A total of 18 strains were isolated from 4 samples of diesel contaminated soils. Among them 5 strains were selected for their ability to degrade styrene and use it as a sole carbon source to produce PHA. These strains were identified as Enterobacter spp. on the basis of 16S rRNA gene sequencing. Bacteria were screened for their ability to produce PHA by utilizing glucose and styrene as a carbon sources. Screening for PHA production was done by Nile blue A, Sudan black B, and phase contrast microscopy and the selected 3 strains showed positive results. Growth kinetics along with time profiling of PHA was performed for glucose and styrene as carbon sources. RESULTS： PHA extraction was done at equal intervals of 12 h by sodium hypochlorite method which showed that these strains accumulate maximum amount of PHA after 48 h in glucose （30.60%）. FTIR analysis of PHA was done which revealed homopolymer PHB and copolymer （PHB-co-PHV） production in strains by utilizing glucose and styrene. Gas chromatography mass spectrometry was carried out to identify the metabolites produced by bacterial strains grown on styrene. Metabolites of styrene degradation included propyne and phenylalanine. Genomic DNA isolation was carried out to amplify phaC gene which encodes PHA synthase enzyme. CONCLUSIONS： The conversion of styrene to polyhydroxyalkanoates （PHA） provides a new and unique link between an aromatic environmental pollutant and aliphatic PHA accumulation.

关键词： biodegradable polymers environmental pollutants PHA FTIR recycling bacteria

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Functional composition of tall-statured trees underpins aboveground biomass in tropical forests

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Journal of Forestry Research 2023年第2期34卷 333-344页

作者： Suwash Kunwar Li-Qiu Wang Maryam Kazempour Larsary Rajeev Chaudhary Puspa Raj Joshi arshad Ali Department of Forest Resources Management College of ForestryNanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China Forest Ecology Research Group College of Life SciencesHebei UniversityBaoding 071002HebeiPeople’s Republic of China Division Forest Offi ce DadeldhuraMinistry of ForestDhangadhiSudurpashchim ProvinceNepal Department of Forestry Faculty of Natural ResourcesUniversity of Guilan43619-96196 SomehsaraIran Division Forest Offi ce PahalmanpurMinistry of ForestDhangadhiSudurpashchim ProvinceNepal Institute of Forestry Tribhuvan UniversityHetauda CampusHetauda 44107Nepal

The influences of trait diversity(i.e.,the niche complementarity effect)and functional composition(i.e.,the mass ratio effect)on aboveground biomass(AGB)is a highly debated topic in forest ***,further studies are needed to explore these mechanisms in unstudied forest ecosystems to enhance our understanding,and to provide guidelines for specific forest ***,we hypothesized that functional composition would drive AGB better than trait diversity and stem size inequality in the(sub-)tropical forests of *** data from 101 forest plots,we tested 25 structural equation models(SEMs)to link elevation,stem DBH inequality,trait diversity(i.e.,trait richness,evenness,dispersion and divergence),functional composition[i.e.,community-weighted of maximum height mean(CWM of Hmax),specific leaf area(CWM of SLA),leaf dry matter content(CWM of LDMC),and wood density(CWM of WD)]and *** best-fitted SEMs indicated that CWM of Hmax promoted AGB while overruling the impacts of trait diversity indices on ***,low trait diversity indices were linked with higher AGB while overruling the effects of CWM of SLA,LDMC and WD on *** addition,AGB decreased with increasing elevation,whereas stem size inequality did not influence *** results suggest that divergent species’functional strategies could shape AGB along an altitudinal gradient in tropical *** argue that forest management practices should include plant functional traits in the management plan for the co-benefits of biodiversity conservation and carbon sequestration that underpins human wellbeing.

关键词： Functional traits Mass ratio Niche complementarity Niche overlap Topography

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沥青基炭纤维的制备及其表征(英文)

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新型炭材料 2009年第1期24卷 83-88页

作者： arshad Hussain Wazir Lutfullah Kakakhel National Centre of Excellence in Physical Chemistry University of Peshawar Peshawar-25120 Pakistan

石油沥青在氮气氛中420℃热缩聚7h,制得软化点为295℃的炭纤维前驱体沥青。此前驱体沥青在单孔纺丝器中熔纺获得沥青纤维。将沥青纤维于空气中320℃稳定化处理,最后在氮气流中1000℃炭化制成炭纤维。应用SEM、TGA、FTIR和XRD对石油沥青... 详细信息

石油沥青在氮气氛中420℃热缩聚7h,制得软化点为295℃的炭纤维前驱体沥青。此前驱体沥青在单孔纺丝器中熔纺获得沥青纤维。将沥青纤维于空气中320℃稳定化处理,最后在氮气流中1000℃炭化制成炭纤维。应用SEM、TGA、FTIR和XRD对石油沥青、前驱体沥青、沥青纤维、预氧化纤维和炭纤维分别进行表征。发现:前驱体沥青中含有质量分数70.5%中间相组分,炭纤维具有径核结构,其最大抗拉强度为650MPa.

关键词：前驱体沥青炭纤维光学显微镜 X-光衍射仪

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Vibration characteristics of FGM circular cylindrical shells filled with fluid using wave propagation approach

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Applied Mathematics and Mechanics(English Edition) 2009年第11期30卷 1393-1404页

作者： Zafar Iqbal Muhammad Nawaz Naeem Nazra Sultana Shahid Hussain arshad Abdul Ghafar Shah Department of Mathematics University of Sargodha Department of Mathematics G. C. University Faisalabad Department of Mathematics University of Sargodha Department of Mathematics The Islamia University of Bahawalpur

The vibration characteristics of a functionally graded material circular cylindrical shell filled with fluid are examined with a wave propagation approach. The shell is filled with an incompressible non-viscous fluid. Axial modal dependence is approximated by exponential functions. A theoretical study of shell vibration frequencies is analyzed for simply supported-simply supported, clamped-simply supported, and clamped-clamped boundary conditions with the fluid effect. The validity and the accuracy of the present method are confirmed by comparing the present results with those available in the literature. Good agreement is observed between the two sets of results.

关键词： functionally graded material Love's shell theory cylindrical shell volumefraction law natural frequency wave propagation

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Assessment of parameters effectiveness in the reserve estimation methods applicable to coal bed methane reservoirs

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Petroleum Research 2023年第1期8卷 44-53页

作者： Farzain Ud Din Kirmani arshad Raza Muhammad Sarfraz Akram Raoof Gholami Institute of Energy and Environmental Engineering University of the PunjabLahorePakistan Department of Petroleum and Gas Engineering University of Engineering and TechnologyLahorePakistan Department of Petroleum Engineering King Fahd University of Petroleum and MineralsSaudi Arabia Department of Energy Resources University of StavangerStavangerNorway

The reserve estimation of coal bed methane(CBM)reservoirs is ascertained through the analytical methods(volumetric method,material balance equation and decline curve analysis).However,the adoption of reserve estimation methods depends on exploration stage and availability of the required *** study deals with the analytical assessment of parameters that participate in effecting the reserve estimation of CBM reservoirs through the analytical *** accurate measurement challenges always exist for the parameters which participate in the reserve estimation of the conventional and unconventional reservoirs because of the inclusion of limitations while ***,the impact of that measurement challenge must be *** study specifies the impact of parametric change on the reserve estimation of CBM reservoirs so that the degree of parametric effectiveness is *** values are adopted which are associated during the evaluation of input parameters for each method to determine the overall impact on potential of CBM *** reveal that change in specific parameters considering each method provide relatively more effect on estimation of ***,the measurement of parameters must be done accurately for assessing reserves of CBM reservoirs based on available methods.

关键词： Reserve estimation Coal bed methane Parameters effectiveness Analytical methods Numerical simulation

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One-pot Synthesis,Crystal Structures and Antimicrobial Activities of Two New 1,4-Disubstituted 1,2,3-Triazole-4-Carboxylates

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Chinese Journal of Structural Chemistry 2015年第1期34卷 26-32页

作者： MUHAMMAD Naeem Ahmed KHAWAJA Ansar Yasin MUHAMMAD Nawaz Tahir IFZAN arshad MURTAZA Madni Department of Chemistry The University of Azad Jammu and Kashmir University of Sargodha Department of Physics Department of Chemistry Quaid-i-Azam University

Two new 1,4-disubstituted 1,2,3-triazoles-4-carboxylates were synthesized via click reaction. Compound 1a was synthesized by the interaction of 6-nitro-tetrazolo[1.5-a]-pyridine with ethyl propynoate at room temperature in the presence of Cu（OAc）2 as a catalyst and THF as solvent. Compound 1b was also synthesized by the same manner except that tert-butyl propionate, instead of ethyl propynoate, was used. The compounds were characterized by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. Compound 1a（C10H9N5O4） crystallizes in the triclinic system, space group P1 with a = 5.0894（9）, b = 8.9834（13）, c = 13.089（2）？, α= 83.041（7）, β= 80.256（7）, γ=87.296（8）°, V = 585.24（16）？3, Z = 2, Mr = 263.22, crystal size（mm） = 0.37 × 0.20 ×0.18,（I 〉 2σ（I）） = 8557, 2493, 1229, Rint = 0.057. Compound 1b（C12H13N5O4） crystallizes in the monoclinic system, space group P21/c with a = 6.8854（5）, b = 21.783（2）, c = 9.3986（8）？,β = 93.239（4）°, V = 1407.4（2）？3, Z = 4, Mr = 291.27, crystal size（mm） = 0.38 × 0.22 × 0.20,（I 〉 2σ（I）） = 11842, 3172, 1866, Rint = 0.047. Antimicrobial assay results showed that the title compounds display excellent activities to different bacterial and fungal strains.

关键词： click reaction triazoles crystal structure antimicrobial activity

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Community based interventions for the prevention and control of Non-Helmintic NTD

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Infectious Diseases of Poverty 2014年第1期3卷 223-234页

作者： Jai K Das Rehana A Salam Ahmed arshad Hasina Maredia Zulfiqar A Bhutta Division of Women&Child Health The Aga Khan UniversityKarachiPakistan Brown University ProvidenceRIUSA Center of Excellence in Women&Child Health The Aga Khan UniversityKarachiPakistan Center for Global Child Health Hospital for Sick ChildrenTorontoCanada

In this paper,we aim to systematically analyze the effectiveness of community based interventions(CBI)for the prevention and control of non-helminthic diseases including dengue,trypanosomiasis,chagas,leishmaniasis,buruli ulcer,leprosy and *** systematically reviewed literature published up to May 2013 and included 62 studies in this *** from our review suggest that CBI including insecticide spraying;insecticide treated bednets and curtains;community education and cleanliness campaigns;chemoprophylaxis through mass drug administration;and treatment have the potential to reduce the incidence and burden of non-helminthic *** of data limited the subgroup analysis for integrated and non-integrated delivery strategies however,qualitative synthesis suggest that integrated delivery is more effective when compared to vertical interventions;however,such integration was possible only because of the existing vertical vector control *** delivered interventions have the potential to achieve wider coverage and sustained community *** these diseases will require a multipronged approach including drug administration,health education,vector control and clean water and sanitation *** would require high level governmental commitment along with strong partnerships among major stakeholders.

关键词： NTDs Non-helminthic Community based interventions

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Surgical and long-term functional outcomes of patients with Duchenne muscular dystrophy following spinal deformity correction

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World Journal of Orthopedics 2023年第6期14卷 411-426页

作者： Simon Roberts Ayesha arshad Athanasios I Tsirikos Department of Spinal Surgery Leeds Teaching Hospitals NHS TrustLeeds LS13EXUnited Kingdom Scottish National Spine Deformity Centre Royal Hospital for Children and Young PeopleEdinburgh EH164TJUnited Kingdom

BACKGROUND Life expectancy in patients with Duchenne muscular dystrophy(DMD)has improved due to advances in medical *** patients develop progressive spinal deformity after loss of ambulatory function and onset of wheelchair dependence for *** is limited published data on the effect of spinal deformity correction on long-term functional outcomes,quality of life(QoL),and satisfaction in DMD *** To investigate the long-term functional outcomes following spinal deformity correction in DMD *** This was a retrospective cohort study from *** was collected from hospital records and *** follow-up,patients completed the muscular dystrophy spine questionnaire(MDSQ).Statistical analysis was performed by linear regression analysis and ANOVA to analyse clinical and radiographic factors significantly associated with MDSQ *** Forty-three patients were included with mean age 14.4 years at *** fusion was performed in 41.9%of *** surgical time was 352.1 min and mean blood loss was 36%of estimated total blood *** hospital stay was 14.1 *** complications occurred in 25.6%of *** preoperative scoliosis was 58°,pelvic obliquity 16.4°,thoracic kyphosis 55.8°,lumbar lordosis 11.1°,coronal balance 3.8 cm,and sagittal balance+6.1 *** surgical correction of scoliosis was 79.2%and of pelvic obliquity was 80.8%.Mean follow-up was 10.9 years(range:2-22.5).Twenty-four patients had died at *** patients completed the MDSQ at mean age 25.4 years(range 15.2-37.3).Two patients were bed-ridden and 7 were on ventilatory *** MDSQ total score was *** 16 patients were satisfied with the results of spinal surgery and would choose surgery again if *** patients(87.5%)reported no severe back pain at *** significantly associated with functional outcomes(MDSQ total score)included greater duration of post-operative follow-up,age,scolios

关键词： Duchenne muscular dystrophy Scoliosis Surgical Functional Outcomes

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Fine-scale habitat differentiation shapes the composition, structure and aboveground biomass but not species richness of a tropical Atlantic forest

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Journal of Forestry Research 2020年第5期31卷 1599-1611页

作者： Alice Cristina Rodrigues Pedro Manuel Villa arshad Ali Walnir Ferreira-Junior Andreza Viana Neri Laboratorio de Ecologia e Evoluc¸ao de Plantas–LEEP Departamento de Biologia VegetalUniversidade Federal de Vic¸osaVic¸osaMinas Gerais CEP 36570-900Brazil Fundacion para la Conservacion de la Biodiversidad Merida 7101MeridaVenezuela College of Forestry Nanjing Forestry UniversityNanjing 210037JiangsuPeople’s Republic of China Setor de Biologia e Meio Ambiente Instituto Federal do Sul de Minas Gerais-IFSULDEMINAS-Campus MachadoHighway Machado-Paraguac¸ukm 3MachadoMG CEP 37750000Brazil

Evaluating the influences of fine-scale habitat heterogeneity on the composition,diversity,structure and functioning of forests is critical to understand how tropical forests will respond to climate change and devise forest management strategies that will enhance biodiversity conservation and aboveground biomass ***,we hypothesized that topographic and soil factors determine fine-scale habitat differentiation,which in turn shape community composition,species richness,structure and aboveground biomass at the local scale in tropical *** test this hypothesis,we selected two areas(each 100×100 m)with contrasting fine-scale topographic conditions where all trees,palms and lianas with a diameter at breast height ≥ 10 cm were tagged and identified to *** each selected area,100 subplots of 10×10 m were *** mainly found that higher topographic variability caused higher habitat differentiation with changes in species composition and community structure,but did not change species *** habitat-scale analyses indicated that,in the less heterogeneous area,the distribution of species was more uniform along a fine-scale topographical gradient with no variation in convexity,which induced changes in structure and aboveground biomass,but not in species *** nonsignificant relationship between species richness and aboveground biomass may be attributable to species redundancy or functional *** study suggests that environmental filtering is a fundamental process for shaping community assembly and forest functioning along a local topographical gradient in tropical forests.

关键词： Community–habitat associations Convexity Rarefaction Topographic variability

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Comparison of Mechanical Properties of Acid and UV Ozone Treated Nanodiamond Epoxy Nanocomposites

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Journal of Materials Science & Technology 2014年第8期30卷 753-758页

作者： Sobia A.Rakha Naveed Ali Yasir A.Haleem Fakhre Alam Aqeel A.Khurram arshad Munir Experimental Physics Labs National Centre for Physics ComplexIslamabad 45320Pakistan Centre of Excellence in Science and Advance Technologies Islamabad 45320Pakistan Centre of Excellence in Solid State Physics University of the PunjabLahore 54590Pakistan Department of Physics Kohat UniversityKohat 26000Pakistan

Nanodiamond（ND） powder was successfully activated by wet chemical method and by exposure of UV/O3 in a chamber followed by mixing in triethylenetetramine（TETA） *** reinforcement role of activated ND in the mechanical properties of epoxy matrix was *** treatments,*** and UV/O3 provide ND surface with chemical functionalities for adhesion with epoxy *** transform infrared spectroscopy was utilized to confirm the attachment of surface groups to the ND *** low content of acid and UV/O3 activated ND was dispersed ultrasonically in the epoxy matrix separately to make *** mechanical properties of the nanocomposites were investigated under three point *** strong interactions among activated ND particles and the epoxy resin provide efficient load transfer interfaces,which enhances the mechanical properties of the *** was found that the flexural strength,modulus,and toughness of 0.1 wt%ND loaded nanocomposites have been enhanced up to 85%,57%,and 39%,respectively for UV/O3 treated ND *** is also found that the optimum ND concentration to achieve maximum reinforcement is 0.1 wt%while higher concentrations lead to decrease in mechanical *** significant improvement of the mechanical properties of the ND/epoxy nanocomposites is attributed to the good dispersion of the functionalized ND in epoxy matrix.

关键词： Nanodiamond Dispersion Mechanical properties Nanocomposites

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