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Assessment of Heavy Metals Pollution in the Sediments of Euphrates River, Iraq

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Journal of Water Resource and Protection 2012年第12期4卷 1009-1023页

作者： Emad A. Mohammad Salah Tahseen A. Zaidan ahmed S. Al-Rawi Department of Applied Geology College of Science University of Anbar Ramadi Iraq Department of Chemistry College of Science University of Anbar Ramadi Iraq

Fourteen bed sediments samples were collected from the Euphrates River in order to determine concentrations, seasonal, spatial and contamination assessment of heavy metals such as Pb, Cd, Zn, Cu, Ni, Co, Fe, Mn and Cr. The mean concentrations are as follows: 2249.47 mg/kg for Fe, 228.18 mg/kg for Mn, 67.08 mg/kg for Ni, 58.4 mg/kg for Cr, 48.00 mg/kg for Zn, 28.16 mg/kg for Co, 22.56 mg/kg for Pb, 18.91 mg/kg for Cu and 1.87 mg/kg for Cd. To assess metal contamination in sediments, sediment quality guidelines were applied. The mean concentration of Cd, Cu, Ni, Fe, Mn, and Cr exceeded the USEPA guideline. The metal contamination in the sediments was also evaluated by appling enrichment factor (EF), contamination factor (CF), geo-accumulation index (Igeo) and pollution load index (PLI). Based on enrichment factor (EF), the Euphrates River sediments have very high enrichment for Pb, extremely high for Cd, moderate for Zn, significant to very high for Ni, very high to extremely high for Co, moderate to significant for Mn and significant to very high for Cr. According to contamination factor (CF), Cd and Cr are responsible for very high contamination. According to Igeo, the Euphrates River sediments are moderately to strongly polluted by Cd. Based on PLI, all sampling sites suggest no overall pollution of site quality.

关键词： Heavy Metals Euphrates River Sediments Pollution Iraq

Multiple Parameter Based Clustering (MPC): Prospective Analysis for Effective Clustering in Wireless Sensor Network (WSN) Using K-Means Algorithm

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Wireless Sensor Network 2012年第1期4卷 18-24页

作者： Md. Asif Khan Israfil Tamim Emdad ahmed M. Abdul Awal 不详

In wireless sensor network cluster architecture is useful because of its inherent suitability for data fusion. In this paper we represent a new approach called Multiple Parameter based Clustering (MPC) embedded with the traditional k-means algorithm which takes different parameters (Node energy level, Euclidian distance from the base station, RSSI, Latency of data to reach base station) into consideration to form clusters. Then the effectiveness of the clusters is evaluated based on the uniformity of the node distribution, Node range per cluster, Intra and Inter cluster distance and required energy level of each centroid. Our result shows that by varying multiple parameters we can create clusters with more uniformly distributed nodes, minimize intra and maximize inter cluster distance and elect less power consuming centroid.

关键词： K-Means Algorithm Energy Efficient Uniform Distribution RSSI Latency

A high-frequency targeted vector-free allele exchange (VFAE) mutagenesis protocol for genome editing in a wide range of bacterial species

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A high-frequency targeted vector-free allele exchange (VFAE)...

Genetic Polymorphism of Kappa Casein （K-CN）in Iraqi Buffalo Using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism

中国生物工程学会第十一届学术年会暨2017年全国生物技术大会

作者： ahmed E.Gomaa Yongliang Yan Min Lin Biotechnology Research Institute Chinese Academy of Agricultural Sciences

The complexity of the bacterial recombination system is a barrier for the construction of bacterial mutants for the further functional investigation of specific genes.A common approach to generate gene replacements in bacteria is a two-step homologous recombination based on homologous recombination,including the recombineering and CRISPR-Cas9 *** protocols are complicated and time-consuming and mostly do not enable easy construction of multiple knock-ins/*** current study describes a single and double crossover recombination system using an optimized Vector-Free Allele Exchange (VFAE)protocol for gene disruption and gene replacement in both the gram-negativeEscherichia coli BL21 and gram-positive Bacillus subtilis 168 strains.

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Journal of Agricultural Science and Technology(A) 2013年第10期3卷 835-841页

作者： Talib ahmed Jaayid Muntaha Yakoub Yousief Bashar Falih Zaqeer Jaafer Mohammed Owaid Animal Production Department College of Agriculture Basrah University Basrah Iraq

This study was carried out the animal production department, genetic engineering lab, college of agriculture, （UoB）, Iraq. The aim of this study was to use the polymerase chain reaction restriction fragment length polymorphism （PCR-RFLP） as a fast, efficient and low cost method to detect the genetic variants of kappa-casein gene （k-CN） in Iraqi buffalo using three different primers specific for bovine k-CN to amplify the gene segment, followed by digestion using restriction enzyme （Hind III） for genotyping. DNA from 50 Iraqi buffaloes was extracted by phenol chloroform method. PCR was carried out in a final reaction volume of 25 μL and the reaction mixture was subjected to standard PCR protocol. The results of this work show that among the examined 50 Iraqi Buffalo were homozygous for the K-CN and genotyped as BB for all three primers but gave different bands. Thus PCR-RFLP using Hind III revealed all the samples to be monomorphic for this locus. The restriction digestion analysis of 397 bp PCR product of k-CN indicates the presence of two fragments of 154 bp and 225 bp for BB-genotype. A 437 bp fragment of the bovine genomic K-CN gene was amplified. One Hind III restriction site is found in position 346 of the amplified fragment of allele k-CN B, yielded 91 bp and 346 bp. Amplified products from Iraqi buffalo （530）, after being digested with Hind III, yielded two separate DNA fragments of different sizes i.e., 160 bp and 370 bp. For the first time completed research such specifications in Iraq, for the first time using molecular biology in genetic identification. Our objectives of this study have been to aid in understanding domestication, Buffalo origin and their history and evolution, to identify genetically unique breeds, to provide an objective basis for conservation decisions and to aid the formulation of breeding plans.

关键词： Polymorphism kappa casein gene Iraqi buffalo Hind III PCR-RFLP.

Evaluation of Real-Time PCR and Culturing for the Detection of Leptospires in Canine Samples

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Advances in Microbiology 2012年第2期2卷 162-170页

作者： ahmed ahmed Henricus L. B. M. Klaasen Mark van der Veen Hans van der Linden Marga G. A. Goris Rudy A. Hartskeerl MSD Animal Health Department Microbiological Research and Development Boxmeer The Netherlands WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis Department of Biomedical Research Royal Tropical Institute Amsterdam The Netherlands WHO/FAO/OIE and National Collaborating Centre for Reference and Research on Leptospirosis Department of Biomedical Research Royal Tropical Institute Amsterdam The Netherlands

Validated real-time PCRs detecting leptospires for veterinary purposes are not readily available. This paper describes the prospective evaluation of a SYBR Green-based real-time PCR on serum samples collected from experimentally infected dogs. Compared to culturing, the assay had a diagnostic sensitivity and specificity of 91.7% and 90.0%, respectively. Culturing for part is complementary to PCR and preferably both should be applied for diagnosis and vaccine challenge experiments. In a subsequent prospective study on the dynamics of experimental infections with serovars Canicola and Copenhageni and serovar complex Bananal-Liangguang in young and adult dogs, the PCR was applied on serum samples in conjunction with culturing on blood, urine and kidney samples with the following results: 1) Leptospires persisted longer in the blood of young dogs than of adult ones;2) Numbers of viable leptospires in the blood are rapidly reduced but DNA remains occasionally detectable up to 7 days post infection;3) Appearance of viable leptospires in the urine follows a biphasic dynamics;4) EDTA hampers effective culturing from blood samples;5) Serovar Canicola persists longer in the blood of dogs than Copenhageni and Bananal-Liangguang. Together with a markedly higher recovery rate from kidney samples (71% compared to respectively 33% and 0% in young dogs), this probably reflects the adaptation power of Canicola to its canine maintenance host. Appearance of leptospires in the urine samples indicates that experimental infections have been successful. PCR presents a valuable adjunct to the diagnosis of veterinary leptospirosis and the follow-up in vaccine protection experiments.

关键词： Leptospirosis Diagnosis PCR Evaluation Canine Experimental Infection Challenge Infection Kinetics

Best practices for prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis

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World Journal of Gastrointestinal Endoscopy 2021年第6期13卷 161-169页

作者： Simcha Weissman Mohamed ahmed Matthew R Baniqued Dean Ehrlich James H Tabibian Department of Medicine Hackensack Meridian Health Palisades Medical CenterNorth BergenNJ 07047United States UCLA Vatche and Tamar Manoukian Division of Digestive Diseases Los AngelesCA 91342United States Director of Endoscopy Division of GastroenterologyDepartment of MedicineOlive View-UCLA Medical CenterSylmarCA 91342United States

Acute pancreatitis is of one the most common gastroenterology-related indications for hospital admissions *** the widespread reliance on endoscopic retrograde cholangiopancreatography(ERCP)for the management of pancreaticobiliary conditions,post-ERCP pancreatitis(PEP)has come to represent an important etiology of acute *** many studies aiming to better understand the pathogenesis and prevention of this iatrogenic disorder,findings have been heterogeneous,and considerable variation in clinical practice ***,we review the literature regarding PEP with the goal to raise awareness of this entity,discuss recent data,and present evidence-based best *** believe this manuscript will be useful for gastrointestinal endoscopists as well as other specialists involved in the management of patients with PEP.

关键词： Post-endoscopic retrograde cholangiopancreatography pancreatitis Endoscopic retrograde cholangiopancreatography Pancreatitis Practice guidelines Pharmacology Prevention

Psychiatric Comorbidity in Patients with Acne

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Open Journal of Psychiatry 2017年第3期7卷 176-185页

作者： Amir Mufaddel Asim ahmed Elnour Abdelaziz A. Omer Esam H. Alshora Alkharj Psychiatric Hospital Riyadh KSA Faculty Pharmacy Program Fatima College of Health Sciences Abu Dhabi/Al Ain UAE Monash University Melbourne Australia Faculty of Medicine Department of Psychiatry University of Khartoum Khartoum Sudan

Acne vulgaris is a chronic inflammatory skin disorder which has a high prevalence among adolescents and young adults and can be associated with emotional and psychological burden on patients. This review aimed to explore psychological factors in patients with acne. Several forms of emotional distress and psychological complications can occur with acne. Such complications may be worse than the physical impact of the skin condition. Current literature suggests that skin changes in acne are associated with changed body image, psychological distress, anxiety, social phobia, suicidal ideation and depression. Population-based studies suggest a significant association between acne and mental distress among both male and female adolescents. Presence of psychological distress is related to severity of acne in some studies. However, other case-controlled studies suggest increased risk for psychological problems in patients with acne regardless of its severity. Stress is suspected to have a role in exacerbations of acne, and the quality of life (QoL) is affected particularly in cases with severe facial acne. Acne treatment can be associated with psychiatric side effects. Isotretinoin may be associated with depression and suicide attempts as shown in several studies but with conflicting results. On the other hand, psychotropic medications (such as antidepressants, antipsychotics and mood stabilizers) can also induce acne. The results of this review indicate the importance of vigilant psychiatric assessment for patients with acne, particularly those receiving isotretinoin, is needed for early diagnosis and treatment of the associated psychiatric co-morbidity.

关键词： Acne Anxiety Depression Isotretinoin Psychodermatology Stress Suicide

Compact Bluetooth/UWB Antenna with Multi-Band Notched Characteristics

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Journal of Electromagnetic Analysis and Applications 2011年第12期3卷 512-518页

作者： ahmed Shaker Saber Helmy Zainud-Deen Kurany Ragb Mahmoud Sabry Mohamed Ibrahem 不详

A small-sized, low-profile, and planar dual band antenna for Bluetooth (2.4 - 2.484 GHz) and ultra-wideband (UWB) (3.1 - 10.6 GHz) with multi-band notched antennas is presented. Two antennas A and B with different types of slots are used to obtain tri-band notched characteristic. In antenna A notched bands, 5 - 6 GHz for WLAN, and 3.3 - 4 GHz for WiMAX, are achieved using a U-slot in ground structure and in the radiating patch. In antenna B two notched bands at 3.3 - 4 GHz, for WiMAX and 7.2 GHz for C-band satellite communication systems are achieved by using a U-slot in ground structure and a H-shaped slot in the radiating patch. The radiation characteristics of the two antennas are calculated using a commercial EM simulator based on Finite Element Method (FEM) and the Finite Integration Technique (FIT). The two antennas show acceptable gain flatness with stable omnidirectional radiation patterns across the integrated Bluetooth and UWB bands.

关键词： Ultra-Wide Band (UWB) Bluetooth Band Notched FEM FIT

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不规则波中多体三浮子波能转换器的优化设计

哈尔滨工程大学学报（英文版） 2023年第3期22卷 475-487页

作者： T.M.ahmed A.R.Bassiouny K.A.Geba Y.Welaya Department of Naval Architecture and Marine Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt Petroleum Marine Services Co.(PMS) Alexandria 23722Egypt

A multi-body wave energy converter,consisting of three floats and modeled as a two body problem,is optimised to enhance its mean absorbed power using the Response Surface Optimisation *** optimisation focuses on two input parameters namely;the floats’diameters and the spacing,in various sea states and at different PTO dampings.A frequency domain analysis is performed for the WEC model scaled at 1∶50 in regular and irregular *** results are validated against numerical and experimental data available in the *** show good agreement against the unmoored model’s added mass,radiation damping,response amplitude operator,mean absorbed power and,capture width *** sea states selected for optimisation are represented by a JONSWAP wave spectrum with,a range of significant wave heights(0.04 to 0.06 m)and a range of peak periods(0.8 to 1.3 s).This corresponds to(2 to 3 m)significant wave heights and(5.6 to 9.2 s)peak periods in full *** show that the optimised WEC model demonstrates good and consistent enhancement of its mean absorbed power and capture width ratio.

关键词： Multi-body wave energy converter Capture width ratio Irregular waves Power absorption Optimisation