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Copper and Mercury in Food, Biological and Pharmaceutical Samples: Spectrophotometric Estimation as Cu(DDTC)2

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American Journal of Analytical Chemistry 2014年第13期5卷 838-850页

作者： mohammad nasir Uddin Nur Mostaq Shah mohammad Amzad Hossain Md. Muzahidul Islam Department of Chemistry University of Chittagong Chittagong Bangladesh

An alternative spectrophotometric method was optimized and validated for the estimation of mercury using diethyldithiocarbamate (DDTC), a common reagent, widely used for the preconcentration and isolation of metal ions in complex matrices followed by their estimation by varied techniques. Diethyldithiocarbamate forms yellow Cu(DDTC)2 with copper and white Hg(DDTC)2 with mercury (having d10 system) which are extracted in CCl4. The UV-visible spectrum of Cu(DDTC)2 is very stable at pH 5.0 and has a maximum absorption (λmax) at 435 nm. Hg(DDTC)2 is more stable than Cu(DDTC)2. Estimation of mercury is based on a quantitative displacement of Cu(II) of Cu(DDTC)2 with the addition of mercury followed by the measurement of reduced absorbance. Primarily, method was optimized and validated for the estimation of copper. Therefore, simultaneous determination of Cu(II) and Hg(II) in mixture is proposed fractionating the extract. The molar specific coefficient (ε) for the mercury was 1.4 × 104 mol﹣1·L·cm﹣1 and for copper was 3.16 × 105 mol﹣1·L·cm﹣1 at 435 nm. The detection limits of Cu2+ and Hg2+ were 0.023 μg·mL﹣1 and 0.029 μg·mL﹣1, respectively. The calibration curve shows good linearity of 0.02 - 12.0 and 0.02 - 15.0 μg·mL﹣1 for the Cu2+ and Hg2+ determination, respectively. Proposed technique was applied to food, biological and pharmaceutical samples for the determination of Cu(II) and Hg(II).

关键词： Copper Mercury Diethyldithiocarbamate Spectrophotometric Method Food Biological Pharmaceutical Samples

Increasing Distance Increasing Bits Substitution (IDIBS) Algorithm for Implementation of VTVB Steganography

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Computer Modeling in Engineering & Sciences 2018年第10期117卷 1-16页

作者： Sahib Khan Arslan Arif Syed Tahir Hussain Rizvi nasir Ahmad Department of Electronics and Telecommunications Politecnico di Torino10129 TorinoItaly DAUIN Politecnico di Torino10129 TorinoItaly Department of Electronic and Electrical Engineering Loughborough UniversityUnited Kingdom

Cryptography and steganography are two important and related fields of information ***,steganography is slightly different in the sense that it hides the existence of secret information from unauthorized *** is one of the most appealing research domains,have applications like copyright protection,data integrity protection and manipulation *** steganography techniques have been proposed in ***,in this work a new information hiding algorithm is *** proposed technique de-correlates frequency components of cover image using discrete cosine transform and uses the least significant bits of frequency components for hiding secret *** tech-nique hides variable number of bits of secret message in different frequency ***,it hides different amount of secret information in different regions of cover im-age and results in enhancement of *** algorithm has the flexibility to change the hiding capacity and quality of final stego *** has been observed from experimental results that a hiding a capacity from 3%to 43%can be achieved with significantly good quality of 41 dB to 37 dB in term of peak signal to noise *** successful recovery of the hidden information need the pattern,called stego key,in which is used in hiding *** algorithm provides twofold security;hiding keeps the existence of hidden information secret and the large key size makes the retrieval of hidden information difficult for intruders.

关键词： VTVB steganography image processing information security data hiding

Stimulants and donors promote megaplasmid pND6-2 horizontal gene transfer in activated sludge

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Journal of Environmental Sciences 2023年第4期126卷 742-753页

作者： Shan Wang Shanshan Li Dan Du Olusegun KAbass Muhammad Salman nasir Wei Yan Department of Environmental Science and Engineering Xi’an Key Laboratory of Solid Waste Recycling and Resource RecoveryXi’an Jiaotong UniversityXi’an 710049China School of Civil and Environmental Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Structures and Environmental Engineering University of AgricultureFaisalabad 38040Pakistan

The activated sludge process is characterized by high microbial density and diversity,both of which facilitate antibiotic resistance gene *** studies have suggested that antibiotic and non-antibiotic drugs at sub-inhibitory concentrations are major inducers of conjugative gene *** self-transmissible plasmid pND6-2 is one of the endogenous plasmids harbored in Pseudomonas putida ND6,which can trigger the transfer of another co-occurring naphthalene-degrading plasmid ***,to illustrate the potential influence of stimulants on conjugative transfer of pND6-2,we evaluated the effects of four antibiotics (ampicillin,gentamycin,kanamycin,and tetracycline) and naphthalene,on the conjugal transfer efficiency of pND6-2 by filter-mating *** findings demonstrated that all stimulants within an optimal dose promoted conjugative transfer of pND6-2from Pseudomonas putida GKND6 to *** KT2440,with tetracycline being the most effective (100μg/L and 10μg/L),as it enhanced pND6-2-mediated intra-genera transfer by approximately one ***,seven AS reactors were constructed with the addition of donors and different stimulants to further elucidate the conjugative behavior of pND6-2 in natural *** stimulants positively affected the conjugal process of pND6-2,while donors reshaped the host abundance in the *** was likely because stimulant addition enhanced the expression levels of conjugation transfer-related ***,Blastocatella and Chitinimonas were identified as the potential receptors of plasmid pND6-2,which was not affected by donor *** findings demonstrate the positive role of sub-inhibitory stimulant treatment on pND6-2 conjugal transfer and the function of donors in re-shaping the host spectrum of pND6-2.

关键词： Antibiotics Naphthalene Donor Conjugative transfer Host range

Repeat cranial tomography in patients with mild head injury and stable neurological examination - a perspective from a developing country

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Chinese Journal of Traumatology 2011年第5期14卷 297-300页

作者： Sadaf nasir Manzar Hussain Department of Radiology Liaquat National HospitalKarachi Pakistan Department of Neurosurgery Department of Surgery Aga Khan University Hospital Karachi Pakistan

Objective： To determine the frequency of altered findings on repeat cranial tomography （CT） in patients with mild head injury along with stable neurological examination at tertiary care ***： Cross-sectional study was done in the Department of Radiology, Liaquat National Hospital, Karachi from January 2008 to September 2010. All patients with mild head injury in terms of Glasgow Coma Scale （GCS） who underwent repeat scan without clinical or neurological deterioration in the emergency department of a tertiary care centre were included. The collected data were accordingly entered and analyzed by the principal investigator using Statistical Package for Social Sciences （SPSS） version ***： In all 275 patients, only 17 （6%） of the patients were found worseing on repeat CT, 120 （43.63%）scans improved, 138 （50.18%） unchanged and 17 （6.18%）worsened. None of these patients showed signs of clinical ***： Our results suggest that for patients with mild head injury and stable neurological examination, only 6% of them show deterioration on repeat CT, especially when patients＇ GCS is below 13.

关键词： Brain injuries Neurologic examination Glasgow coma scale Tomography

Computing and Implementation of a Controlled Telepresence Robot

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Intelligent Automation & Soft Computing 2023年第8期37卷 1569-1585页

作者： Ali A.Altalbe Aamir Shahzad Muhammad nasir Khan Prince Sattam Bin Abdulaziz University Al-Kharj11942Saudi Arabia Faculty of Computing and Information Technology King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Mechanical Engineering The University of LahoreLahore54000Pakistan Department of Electrical Engineering GC University LahoreLahore54000Pakistan

The development of human-robot interaction has been continu-ously increasing for the last *** this development,it has become simpler and safe interactions using a remotely controlled telepresence robot in an insecure and hazardous *** audio-video communication connection or data transmission stability has already been well handled by fast-growing technologies such as 5G and ***,the design of the phys-ical parameters,e.g.,maneuverability,controllability,and stability,still needs ***,the paper aims to present a systematic,controlled design and implementation of a telepresence mobile *** primary focus of this paper is to perform the computational analysis and experimental implementa-tion design with sophisticated position control,which autonomously controls the robot’s position and speed when reaching an obstacle.A system model and a position controller design are developed with root locus *** design robot results are verified experimentally,showing the robot’s agreement and control in the desired *** robot was tested by considering various parameters:driving straight ahead,right turn,self-localization and complex *** results prove that the proposed approach is flexible and adaptable and gives a better *** experimental results show that the proposed method significantly minimizes the obstacle hits.

关键词： Computing telepresence healthcare system position controller mobile robot

SSZ Semail Ophiolite vs MORB Masirah Ophiolite: A Perspective from Podiform Chromitites

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Acta Geologica Sinica(English Edition) 2020年第S1期94卷 51-52页

作者： Sobhi nasir UNESCO Chair for Ophiolite Studies Sultan Qaboos University Oman

One of the major topics of debate in ophiolite geology is the original tectonic setting of ophiolites. New studies show that most ophiolites are formed more frequently in a suprasubduction zone(SSZ) environment and that only a very small number of ophiolites have formed in an oceanic range(MOR). The Masirah ophiolite is one of the few oceanic ridge ophiolites that have been preserved, and the evidence that was formed in a subduction environment is missing(Moseley and Abbotts 1979, Dilek and Furnes, 2011;Rollinson, 2017). Masirah Island, the Batain and Ras Madrah areas of eastern Oman are almost entirely composed of a well-developed ophiolite, known as the Masirah ophiolite(Fig. 1), which is, however, completely unrelated to the nearby Semail Ophiolite in the northern Oman Mountains(Fig. 2). The Masirah ophiolite is Jurassic in age and represents oceanic lithosphere derived from the Indian Ocean, but is about 15–20 Myr later than emplacement of midCretaceous Semail ophiolite in northern Oman. The presence of basaltic to rhyolitic lavas of calc-alkaline affinity and boninites in the lava sequence of the Semail ophiolite led several researchers to propose a back-arc basin model for this ophiolite(e.g. Tamura and Arai, 2006;Godard et al., 2008;Rollinson and Adetunji, 2015). The Masirah Ophiolite shows close affinities with MORB peridotites in general. Most of the olivine from the Masirah harzburgites show Fo contents that are similar to those of olivine from MORB. Both pyroxenes in these harzburgites have similar Mg# values, Al2O3 and Cr2O3 contents to those of pyroxenes from MORB peridotites. The observed primitive mantlenormalized REE patterns showing enrichment in LREEs indicate that the Masirah peridotites have been modified by fluids or melts enriched in LREEs in a MORB environment. Podiform chromitites housed in ophiolites today interpreted as magmatic deposits formed during the reaction of molten rock in environments spike in the middle of the ocean(MOR) or supra

关键词： Masirah ophiolite Semail ophiolite MOR subduction chromitite

Thermal Properties of Se100–xZnxGlassy System

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Materials Sciences and Applications 2011年第5期2卷 289-298页

作者： Mohd nasir Mohd Abdul Majeed Khan Mushahid Husain mohammad Zulfequar 不详

The crystallization process in Se100–xZnx glassy system is investigated using differential scanning calorimeters (DSC). The samples are prepared by conventional melt-quenching technique in the composition range 2 ≤ x ≤ 20 (at%). Non-isothermal measurements are carried out for different heating rates .The value of the glass transition temperature Tg the crystallization temperature Tc and the crystallization peak temperature Tp, are found to be depending upon both heating rate as well as the composition from thermal analytical data. The investigation of crystallization kinetics indicates a single stage crystallization process. The glass transition energy Eg and the crystallization activation energy Ec are also evaluated from thermal analytical data. The analyzer has been used the most reliable non-isothermal kinetic methods. The value of kinetics parameters Eg, Ec and ‘n’ are calculated using non-isothermal kinetics methods. The analysis shows that the incorporation of Zinc content has a strong influence on the crystallization mechanism for the Se100–xZnx glassy system.

关键词： Chalcogenide Glasses Amorphous Crystallization Kinetics DSC Non-Isothermal

Potato Virus Y mRNA Expression Knockdown Mediated by siRNAs in Cultured Mammalian Cell Line

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Virologica Sinica 2011年第2期26卷 105-113页

作者： Bushra Tabassum Idrees Ahmad nasir Tayyab Husnain National Centre of Excellence in Molecular Biology(CEMB) University of the Punjab

RNA interference(RNAi) is a powerful tool for functional gene analysis which has been successfully used to downregulate the expression levels of target *** goal of this research was to provide a highly robust and concise methodology for in-vitro screening of efficient siRNAs from a bulk to be used as a tool to protect potato plants against PVY *** our study,a 480bp fragment of the capsid protein gene of potato virus Y(CP-PVY) was used as a target to downregulate PVY mRNA expression in-vitro,as the CP gene interferes with viral uncoating,translation and replication.A total of six siRNAs were designed and screened through transient transfection assay and knockdown in expression of CP-PVY mRNA was calculated in CHO-k ***-PVY mRNA knockdown efficiency was analyzed by RT-PCR and real-time PCR of CHO-k cells co-transfected with a CP gene construct and *** biological replicates were performed in this *** our findings,one CP gene specific siRNA out of a total of six was found to be the most effective for knockdown of CP-PVY mRNA in transfected CHO-k cells by up to 80%-90%.

关键词： RNAi Potato virus Y siRNA in-vitro Expression knockdown Transfection

State of Health Estimation of LiFePO_(4) Batteries for Battery Management Systems

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Computers, Materials & Continua 2022年第11期73卷 3149-3164页

作者： Areeb Khalid Syed Abdul Rahman Kashif Noor Ul Ain Ali nasir Department of Electrical Engineering University of Engineering and TechnologyLahorePakistan Department of Electrical Engineering University of Central PunjabLahorePakistan

When considering the mechanism of the batteries,the capacity reduction at storage(when not in use)and cycling(during use)and increase of internal resistance is because of degradation in the chemical composition inside the *** optimize battery usage,a battery management system(BMS)is used to estimate possible aging effects while different load profiles are requested from the *** is specifically seen in a case when the vehicle is connected to the net(online through BMS).During this process,the BMS chooses the optimized load profiles based on the least aging effects on the battery *** major focus of this paper is to design an algorithm/model for lithium iron phosphate(LiFePO4)*** model of the batteries is based on the accelerated aging test data(data from the beginning of life till the end of life).The objective is to develop an algorithm based on the actual battery trend during the whole life of the *** the analysis of the test data,the complete trend of the battery aging and the factors on which the aging is depending on is identified,the aging model can then be recalibrated to avoid any differences in the production process during cell *** validation of the model was carried out at the end by utilizing different driving profiles at different C-rates and different ambient temperatures.A Linear and non-linear model-based approach is used based on statistical *** parameterization was carried out by dividing the data into small chunks and estimating the parameters for the individual ***-adaptive characteristic map using a lookup table was also *** nonlinear model was chosen as the best candidate among all other approaches for longer validation of 8-month data with real driving data set.

关键词： Aging model state of health lithium-ion cells battery management system state of charge battery modeling