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Chinese Journal of.Polymer Science 2007年第5期25卷 519-523页

作者： N.C. Daf.der M.E. Haque f. akhtar Nuclear and Radiation Chemistry Division Institute of Nuclear Science ＆ Technology Bangladesh Atomic Energy Commission P. O. Box 3787 Dhaka Bangladesh

Natural rubber latex （NRL） and methyl methacrylate （MMA） graf.ed rubber latex were blended in dif.erent ratios and irradiated at various absorbed doses by gamma rays f.om Co-60 source at room temperature. The tensile properties, swelling ratio and permanent set were measured. The maximum tensile strength and modulus at 500% elongation were obtained at an absorbed dose of.8 kGy. Modulus increases f.om 6.99 MPa to 9.87 MPa f.r an increase in proportion of.MMA graf.ed rubber f.om 40% to 60% in the blend at similar absorbed dose. Elongation at break and swelling ratio decrease with increasing absorbed dose as well as the MMA graf.ed rubber content in the blends. The decreasing trend of.permanent set is high up to 5 kGy absorbed dose, and beyond that dose, it becomes almost f.at.

关键词： Natural rubber latex MMA graf.ed rubber latex Blend rubber Irradiation Cross-link.

OPTIMIZATION Of.THE SYNTHESIS Of.ACRYLAMIDE HYDROGEL BY γ-RAY IRRADIATION

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Chinese Journal of.Polymer Science 2004年第3期22卷 253-258页

作者： M.A. Chowdhury M.M. Alam M.f. Mina f. akhtar S.E. Kabir Department of.Chemistry Faculty of Science Jahangir Nagar University Dhaka BangladeshNRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh NRCD INST AERE GPO Box-3787 Dhaka Bangladesh Department of Chemistry Faculty of Science Jahangir Nagar University Dhaka Bangladesh

Hydrogels have been synthesized f.om 10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of.acrylamide monomer by gamma radiation employing doses in the range of.0.2-30 kGy f.om a Co-60 source. The ef.ect of.solution concentration, γ-ray dose, pH and time was studied in order to observe the optimizing conditions in the characterization of.hydrogels. Gel f.action increases with dose f.r all concentrations indicating hundred-percentage conversion of.gel at doses 5 kGy f.r homogenous solutions in the range of.20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% monomer makes an inhomogeneous solution which stile gives about 100% gel f.action. Swelling of.hydrogels under water with respect to time varies with both the doses and concentrations due to the change of.crosslinking density in the gels. The maximum volume change of.hydrogels during swelling and water desorption mainly occurs within 24 h. Swelling is also enhanced with the rise of.pH due to change of.ionic content of.the solvent. Considering the amount of.gel f.action and the properties of.hydrogel, the samples prepared f.om 20% solution at 5 kGy show better results. Moreover, the ef.ect of.bacteria on hydrogel was f.und to be nil, suggesting a prohibition of.growth of.microorganism in it.

关键词： Hydrogel Acrylamide γ-radiation Swelling Microorganism

A new class of.generalized quasi-variational inequalities with applications to Oseen problems under nonsmooth boundary conditions

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Science China Mathematics 2024年第2期67卷 315-338页

作者： Shengda Zeng akhtar A.Khan Stanislaw Migórski Guangxi Colleges and Universities Key Laboratory of.Complex System Optimization and Big Data Processing Yulin Normal UniversityYulin 537000China f.culty of.Mathematics and Computer Science Jagiellonian University in Krak´owKrak´ow 30348Poland Center f.r Applied and Computational Mathematics School of Mathematical SciencesRochester Institute of TechnologyRochesterNY 14623USA College of.Sciences Beibu Gulf UniversityQinzhou 535000China

In this paper, we study a generalized quasi-variational inequality (GQVI f.r short) with twomultivalued operators and two bif.nctions in a Banach space setting. A coupling of.the Tychonov f.xedpoint principle and the Katutani-Ky f.n theorem f.r multivalued maps is employed to prove a new existencetheorem f.r the GQVI. We also study a nonlinear optimal control problem driven by the GQVI and givesuf.icient conditions ensuring the existence of.an optimal control. f.nally, we illustrate the applicability of.thetheoretical results in the study of.a complicated Oseen problem f.r non-Newtonian f.uids with a nonmonotone andmultivalued slip boundary condition (i.e., a generalized f.iction constitutive law), a generalized leak boundarycondition, a unilateral contact condition of.Signorini’s type and an implicit obstacle ef.ect, in which themultivalued slip boundary condition is described by the generalized Clarke subgradient, and the leak boundarycondition is f.rmulated by the convex subdif.erential operator f.r a convex superpotential.

关键词： generalized quasi-variational inequality existence theorem optimal control Kakutani-Ky f.n theorem Oseen problem non-Newtonian f.uid nonmonotone slip boundary condition

The Application of.Artif.cial Intelligence in Alzheimer’s Research

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Tsinghua Science and Technology 2024年第1期29卷 13-33页

作者： Qing Zhao Hanrui Xu Jianqiang Li f.heem akhtar Rajput Liyan Qiao f.culty of.Inf.rmation Technology Beijing University of TechnologyBeijing 100124China School of.Medicine Tsinghua UniversityBeijing 100084China Department of.Computer Science Sukkur IBA UniversitySukkur 65200Pakistan Department of.Neurology Tsinghua University Yuquan HospitalBeijing 100040China

Alzheimer's disease(AD)is an irreversible and neurodegenerative disease that slowly impairs memory and neurocognitive f.nction,but the etiology of.AD is still *** the explosive growth of.electronic health data,the application of.artif.cial inteligence(Al)in the healthcare setting provides excellent potential f.r exploring etiology and personalized treatment approaches,and improving the disease's diagnostic and prognostic *** paper f.rst brief.y introduces Al technologies and applications in medicine,and then presents a comprehensive review of.Al in *** simple,it includes etiology discovery based on genetic data,computer-aided diagnosis(CAD),computer-aided prognosis(CAP)of.AD using multi-modality data(genetic,neuroimaging and linguistic data),and pharmacological or non-pharmacological approaches f.r treating ***,some popular publicly available AD datasets are introduced,which are important f.r advancing Al technologies in AD ***,core research challenges and f.ture research directions are discussed.

关键词： Alzheimer's disease artif.cial intelligence etiology discovery computer-aided diagnosis computer-aided prognosis treatment

Tuning structural,electrical,dielectric and magnetic properties of.Mg-Cu-Co f.rrites via dysprosium(Dy^(3+))doping

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Journal of.Rare Earths 2024年第1期42卷 137-146,I0005页

作者： Maria akhtar M.S.Hasan Nasir Amin N.A.Morley Muhammad Imran Arshad Department of.Physics Government College UniversityFaisalabad38000Pakistan Department of.Physics The University of Lahore53700Pakistan Department of.Materials Science and Engineering The University of SheffieldS13JDUK Department of.Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted Mg0.5Cu0.25Co0.25f.2-xDyxO4(0.0≤x≤0.04 with the step interval of.0.01)sof. f.rrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray dif.raction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDS),f.urier transf.rm inf.ared(f.IR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSM)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm f.r sample x=*** non-unif.rm grain growth was demonstrated by micrographs and impurity-f.ee elemental composition was observed f.om EDX *** DC resistivity has an increasing and decreasing trend in f.rromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of.1010Ω·cm,and the activation energy is 0.944 eV f.r samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in f.equency f.om 8 Hz to 8 *** minimum dielectric loss at high f.equency is f.und f.r sample x=*** coercivity(Hc)and saturation magnetization(Ms)are f.und in the ranges of.520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations conf.rm that dysprosium(x=0.03)doped MCC-sof. f.rrites may be applicable in transf.rmer cores,microwave absorbance,and telecommunication devices.

关键词： Sof. f.rrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Base Pressure Control with Semi-Circular Ribs at Critical Mach Number

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f.uid Dynamics & Materials Processing 2024年第9期20卷 2007-2028页

作者： Ambareen Khan Sher Af.han Khan Mohammed Nishat akhtar Abdul Aabid Muneer Baig School of.Aerospace Engineering Universiti Sains MalaysiaPenang11600Malaysia Department of.Mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaKuala Lumpur59000Malaysia Department of.Engineering Management College of EngineeringPrince Sultan UniversityP.O.Box 66833Riyadh11586Saudi Arabia

When better f.el-air mixing in the combustion chamber or a reduction in base drag are required in vehicles,rockets,and aeroplanes,the base pressure control is *** the base pressure and drag is necessary in both *** this work,semi-circular ribs with varying diameters(2,4,and 6 mm)positioned at six distinct positions(0.5D,1D,1.5D,2D,3D,and 4D)inside a square duct with a side of.15 mm are proposed as an ef.icient way to apply the passive control ***-depth research is done on optimising rib size f.r various rib *** to this study,the base pressure rises as rib height ***,the optimal location f.r the semi-circular ribs with a diameter of.2 mm is at *** 1D location appears to be optimal f.r the 4 mm size as *** the 6 mm size,however,the 4D position f.lls this f.nction.

关键词： Base pressure nozzle pressure ratio base drag sonic Mach number passive control

Impact of.numerous larval diets on the biology of.pink bollworm Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)under laboratory conditions

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Journal of.Cotton Research 2024年第1期7卷 69-78页

作者： akhtar Shamim ARIf.Muhammad Jalal GOGI Muhammad Dildar HAQ Imran-ul Department of.Entomology University of Agriculture FaisalabadPunjabPakistan Ayub Agricultural Research Institute(Entomological Research Institute) FaisalabadPunjabPakistan Department of.Plant Pathology University of AgricultureFaisalabadPunjabPakistan

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 *** in view the f.cts like limited research investigations,unavailability,and high cost of.artif.cial diet’s constituents and their premixes,the present research investigations on the dietary aspect of.*** were *** larvae of.*** were reared on dif.erent diets that were prepared using indigenous *** 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 *** to cotton bolls and wheat germ meal were okra seed sprouts,okra f.uit,cottonseed meal,and okra seed meals,which were included in the study to introduce an ef.icient and economic mass-rearing *** The larval development completed in 19.68d±0.05 d with a weight of.20.18mg±0.20 mg at the f.urth instar f.d on the cottonseed meal-based diet instead of.wheat germ meal based *** the same diet,84.00%±4.00%,17.24 mg±0.03 mg,and 7.76d±0.06 d were recorded as pupae f.rmation,pupal weight,and pupal duration,*** emergence,76.00%±1.00%was recorded f.om pupae collected f.om larvae raised on cottonseed meal-based *** male and f.male moths lived f.r 40.25d±0.10 d,and 44.34d±0.11 d,*** deposited 21.28±0.04 eggs per day with the viability of.65.78%±0.14%.The larval mortal-ity at the f.urth instar was 37.20%±1.36%and malf.rmed pupation of.12.00%±1.41%was *** 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,*** This research is of.novel nature as it provides a concis

关键词： Artif.cial diets Cottonseed meal Laboratory rearing Pectinophora gossypiella Wheat germ meal

Acute Kidney Injury with Rhabdomyolysis: 25 Years Experience f.om a Tertiary Care Center

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Open Journal of.Nephrology 2015年第3期5卷 67-74页

作者： Rubina Naqvi f. akhtar E. Ahmed A. Naqvi A. Rizvi Sindh Institute of.Urology and Transplantation (SIUT) Karachi Pakistan

Objective: To describe patients presenting with acute kidney injury af.er rhabdomyolysis at a tertiary renal care center in Pakistan. Patients and Methods: An observational cohort of.patients identif.ed as having acute kidney injury (AKI) with rhabdomyolysis, which was diagnosed by rise in creatinine phosphokinase (CK) and lactate dehydrogenase (LDH) more than 4 times the ref.rence range whereas AKI was def.ned according to RIf.E criteria. On ultrasonography, all patients had normal size non obstructed kidneys, and no other co morbid. Results: Between January1990 to December 2014, 334 patients with rhabdomyolysis and AKI registered to this hospital. Mean age was 28.22 ± 11.22 years with M:f.ratio of.3.33:1. Mean values of.CK and LDH were 597,749.790 ± 180,461.360 and 4077.026 ± 5050.704 U/L with ref.rence range of.26 - 174 U/L and 91 - 180 U/L respectively. We divided the study population into 4 groups over timeline. Rhabdomyolysis etiology was divided in 3 groups;1) traumatic, 2) non-traumatic exertional, and 3) non-traumatic non-exertional. In the last group, which spans f.om 2010-2014, we treated many cases with toxic rhabdomyolysis and main toxin was paraphenylenediamine (PPD). The other causes showed more or less same prevalence over two and a half.decade, except non-traymatic exertional which has decreased during last 5 years without any explainable cause. Renal replacement therapy (RRT) was required on arrival in 94% cases. Complete renal recovery was observed in 70%, while 15.86% died and 10% were lost during recovery phase. A small number 2.69% lef. against medical advice during acute phase of.illness and 0.8% developed chronic kidney disease (CKD). Conclusion: The common clinical conditions f.und associated with rhabdomyolysis and AKI includes trauma, immobilization, sepsis, overexertion, and drugs and toxins. In recent years, we have seen many young patients with PPD poisoning;we have f.und good renal recovery in patients who survived initial 2 - 3 weeks.

关键词： Acute Kidney Injury Rhabdomyolysis RIf.E Criteria Torture Toxins PPD

Two-Stream Approximation to the Radiative Transf.r Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of.Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of.the interaction between solar radiation and the Earth's atmosphere is f.rmalized by the radiative transf.r equation(RTE), whose resolution calls f.r two-stream approximations among other methods. This paper proposes a new two-stream approximation of.the RTE with the development of.the phase f.nction and the intensity into a third-order series of.Legendre polynomials. This new approach, which adds one more term in the expression of.the intensity and the phase f.nction, allows in the conditions of.a plane parallel atmosphere a new mathematical f.rmulation of.γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta f.nction and Modif.ed Eddington, and second-order approximation methods with ref.rence to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion f.nction of.the proposed New Method using the f.ndamental def.nition of.two-stream approximation(f.TSA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision f.r wide domains of.the zenith angle μ 0, but tends to deviate f.om the Disort method with the zenith angle, especially f.r high values of.optical thickness. In spite of.this divergence in ref.ectance f.r high values of.optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained f.r most cases of.optical thickness in this study. An analysis of.the Legendre polynomial series f.r simple f.nctions shows that the high precision is due to the f.ct that the approximated f.nctions ameliorate the accuracy when the order of.approximation increases, although it has been proven that there is a limit order depending on the f.nction f.om which the precision is lost. This observation indicates that increasing the order of.app

关键词： Radiative Transf.r Equation two-stream method Legendre polynomial optical thickness moments of.specif.c intensity conversion f.nction transmittance ref.ectance

Clinical studies in COVID-related olf.ctory disorders:Review of.an institutional experience

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World Journal of.Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 129-136页

作者： Theresa Tharakan Dorina Kallogjeri Jay f.Piccirillo Department of.Otolaryngology-Head and Neck Surgery Clinical Outcomes Research OfficeSchool of MedicineWashington University in St LouisSt LouisMissouriUSA

Objective:To share a single institutional experience with clinical research on COVID-related olf.ctory dysf.nction(OD).Data Source/Method:Narrative review of.published original data and ongoing clinical trials on COVID-related OD at Washington University f.om 2020 to ***:There were three new diagnostic-/patient-reported outcome measures developed and *** report f.ve clinical trials of.interventions f.r COVID-related olf.ctory disorders:combined Visual-Olf.ctory Training(VOLT)with patient-pref.rred scents versus standard olf.ctory training(VOLT trial),oral gabapentin versus placebo(Gabapentin f.r the Relief.of.Acquired Chemosensory Experience trial),nasal theophylline irrigations versus placebo(Smell Changes and Ef.icacy of.Nasal Theophylline trial),stellate ganglion block(single-arm),and mindf.lness-based stress reduction(MBSR)versus lif.style intervention(MBSR trial).Conclusions:Initial intervention trials f.r COVID-related OD have shown potential f.r improving subjective and objective olf.ctory ***,there remains no gold standard treatment that def.nitively outperf.rms placebo in controlled ***,continued investigation of.novel therapeutic strategies f.r COVID-related OD is necessary to maximize olf.ctory outcomes f.r af.ected patients.

关键词： chemosensory disorders COVID olf.ctory dysf.nction