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Nano Research 2023年第4期16卷 4793-4802页

作者： Weiyuan Ding ali saad Yuchen Wu Zhiwei Wang Xiuting Li Institute for Advanced Study Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

Rational construction of active components has been the biggest challenge in preparing efficient bifunctional oxygen ***,electrospinning and chemical vapor deposition(CVD)were employed to embed active species including FeCo nanoparticles,MNx(M=Fe,Co),and FePx in porous and graphitized carbon nanotubes(CNTs)/carbon nanofiber(CNF).The as-prepared FeCo@CoNx@FePx/C exhibited a half-wave potential as high as 0.86 V in oxygen reduction reaction(ORR)and low oxygen evolution reaction(OER)overpotential of 368 mV at 10 mA·cm^(−2),which are superior to Pt/C(0.83 V)and IrO_(2)(375 mV)*** assembled Zn-air battery(ZAB)showed a high energy efficiency(Edischarge/Echarge)of 65%at 20 mA·cm^(−2)and stabilized for 700 charge-discharge *** spectroscopic and microscopic characterizations evidenced that the outstanding bifunctionality of the electrocatalyst can be ascribed to three main reasons:First,FeCo nanoparticles are rich in MOH/MOOH active sites for OER,and FePx/CNTs constructed with CVD also modulate electronic structure to improve electron transfer;second,both MNx in carbon matrix and FePx/CNTs are highly active towards ORR;third,the CNTs/CNF are highly porous and graphitized,which promotes mass transport and improves electrical conductivity and stability of the *** work gives important implications on the design of bifunctional electrocatalysts.

关键词： carbon nanotubes(CNTs)/carbon nanofiber(CNF)-supported multi-active components oxygen reduction reaction oxygen evolution reaction zinc-air battery

A computer-based image analysis for tear ferning featuring

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Journal of Innovative Optical Health Sciences 2015年第5期8卷 40-49页

作者： ali S.saad Gamal A.El-Hiti ali M.Masmali Department of Biomedical Technology College of Applied Medical Sciences King Saud University P.O.Box 10219 Riyadh 11433Saudi Arabia Cornea Research Chair(CRC) Department of Optometry College of Applied Medical SciencesKing Saud University Riyadh 11433Saudi Arabia

The present work focuses on the development of a novel computer-based approach for tear ferning(TF)*** original TF images of the recently developedfive-point grading scale have been used to assign a grade for any TF image automatically.A vector characteristic(VC)representing each grade was built using the reference images.A weighted combination between features selected from textures analysis using gray level co-occurrence matrix(GLCM),power spectrum(PS)analysis and linear specificity of the image were used to build the VC of each grade.A total of 14 features from texture analysis were *** at di®erent frequency points and number of line segments in each image were also *** features from GLCM have shown significant di®erences between the recently developed grading scale images which are:angular second moment at 0and 45,contrast,and correlation at 0and 45;thesefive features were all included in the characteristic *** specific power frequencies were used in the VC because of the discrimination *** of line segments was also chosen because of dissimilarities between images.A VC for each grade of TF reference images was constructed and was found to be significantly different from each other'*** is a basic and fundamental step toward an automatic grading for computer-based diagnosis for dry eye.

关键词： Objective grading tear ferning new grading scale texture analysis image processing PS

Antibacterial mechanism with consequent cytotoxicity of different reinforcements in biodegradable magnesium and zinc alloys: A review

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Journal of Magnesium and Alloys 2023年第9期11卷 3038-3058页

作者： Chowdhury Ahmed Shahed Faiz Ahmad Ebru Günister Farhana Mohd Foudzi saad ali Khurshid Malik Wan Sharuzi Wan Harun Department of Mechanical Engineering Universiti Teknologi PETRONAS(UTP)32610Seri IskandarPerakMalaysia Faculty of Engineering and Natural Sciences Department of Mechanical EngineeringIstanbul Health and Technology UniversityIstanbulTurkey Department of Mechanical and Manufacturing Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Faculty of Mechanical&Automotive Engineering Technology Universiti Malaysia Pahang26600 PekanPahangMalaysia

Benefits achieved by the biodegradable magnesium(Mg) and zinc(Zn) implants could be suppressed due to the invasion of infectious microbial, common bacteria, and fungi. Postoperative medications and the antibacterial properties of pure Mg and Zn are insufficient against biofilm and antibiotic-resistant bacteria, bringing osteomyelitis, necrosis, and even death. This study evaluates the antibacterial performance of biodegradable Mg and Zn alloys of different reinforcements, including silver(Ag), copper(Cu), lithium(Li), and gallium(Ga). Copper ions(Cu^(2+)) can eradicate biofilms and antibiotic-resistant bacteria by extracting electrons from the cellular structure. Silver ion(Ag^(+)) kills bacteria by creating bonds with the thiol group. Gallium ion(Ga^(3+)) inhibits ferric ion(Fe^(3+)) absorption, leading to nutrient deficiency and bacterial death. Nanoparticles and reactive oxygen species(ROS) can penetrate bacteria cell walls directly, develop bonds with receptors, and damage nucleotides. Antibacterial action depends on the alkali nature of metal ions and their degradation rate, which often causes cytotoxicity in living cells. Therefore, this review emphasizes the insight into degradation rate, antibacterial mechanism, and their consequent cytotoxicity and observes the correlation between antibacterial performance and oxidation number of metal ions.

关键词： Biodegradable materials Biomedical implants Antibacterial mechanism Cytotoxicity Reactive oxygen species

Room Temperature Synthesis of Vertically aligned Amorphous Ultrathin NiCo-LDH Nanosheets Bifunctional Flexible Supercapacitor Electrodes

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Energy & Environmental Materials 2024年第2期7卷 277-286页

作者： Kwadwo Asare Owusu Zhaoyang Wang ali saad Felix Ofori Boakye Muhammad Asim Mushtaq Muhammad Tahir Ghulam Yasin Dongqing Liu Zhengchun Peng Xingke Cai Institute for Advanced Study Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronics Shenzhen University3688 Nanhai BoulevardNanshan DistrictShenzhen 518060China School of Chemistry and Materials Science Hubei Engineering UniversityNo.272 Traffic AvenueXiaogan 432000China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyNo.122 Luoshi RoadWuhan 430070China Key Laboratory of Green Printing CAS Research Centre for Excellence in Molecular ScienceInstitute of Chemistry Chinese Academy of Sciences(ICCAS)Beijing 100190China College of Mechatronics and Control Engineering Shenzhen University3688 Nanhai BoulevardNanshan DistrictShenzhen 518050China

Developing a simple scalable method to fabricate electrodes with high capacity and wide voltage range is desired for the real use of electrochemical ***,we synthesized amorphous NiCo-LDH nanosheets vertically aligned on activated carbon cloth substrate,which was in situ transformed from Co-metal-organic framework materials nano-columns by a simple ion exchange process at room *** to the amorphous and vertically aligned ultrathin structure of NiCo-LDH,the NiCo-LDH/activated carbon cloth composites present high areal capacities of 3770 and 1480 mF cm^(-2)as cathode and anode at 2 mA cm^(-2),and 79.5%and 80%capacity have been preserved at 50 mA cm^(-2).In the meantime,they all showed excellent cycling performance with negligible change after>10000 *** fabricating them into an asymmetric supercapacitor,the device achieves high energy densities(5.61 mWh cm^(-2)and 0.352 mW cm^(-3)).This work provides an innovative strategy for simplifying the design of supercapacitors as well as providing a new understanding of improving the rate capabilities/cycling stability of NiCo-LDH materials.

关键词： amorphous nanosheets aqueous supercapacitor high volumetric/areal energy density NiCo-LDH room temperature synthesis

A novel t(3;12)(q21;p13) translocation in a patient with accelerated chronic myeloid leukemia after imatinib and nilotinib therapy

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Cancer Biology & Medicine 2013年第1期10卷 47-51页

作者： Ayda Bennour Ikram Tabka Yosra Ben Youssef Zahra Kmeira Abderrahim Khelif ali saad Halima Sennana Department of Cytogenetics Molecular Genetics and Reproductive Biology Farhat Hached University Teaching Hospital Department of Clinical Hematology Farhat Hached Hospital

The acquisition of secondary chromosomal aberrations in chronic myeloid leukemia (CML) patients with Philadelphia chromosome-positive (Ph+) karyotype signifies clonal evolution associated with the progression of the disease to its accelerated or blastic phase. Therefore, these aberrations have clinical and biological significance. T(3;12)(q26;p13), which is a recurrent chromosomal aberration observed in myeloid malignancies, is typically associated with dysplasia of megakaryocytes, multilineage involvement, short duration of any blastic phase, and extremely poor prognosis. We have identified a recurrent reciprocal translocation between chromosomes 3 and 12 with different breakpoint at bands 3q21 in the malignant cells from a 28-year-old man. The patient was initially diagnosed as having Ph+ CML in the chronic phase. The t(3;12)(q21;p13) translocation occurred 4 years after the patient was first diagnosed with CML while undergoing tyrosine kinase inhibitor therapy. We confirmed the t(3;12)(q21;p13) translocation via fluorescence in situ hybridization assay by using whole-chromosome paint probes for chromosomes 3 and 12. Our findings demonstrate that, similar to other recurrent translocations involving 3q26 such as t(3;3) and t(3;21), the t(3;12)(q21;p13) translocation is implicated not only in myelodysplastic syndrome and acute myeloid leukemia but also in the progression of CML. These findings extend the disease spectrum of this cytogenetic aberration.

关键词： Philadelphia chromosome t(3 12)(q21 p13) chronic myeloid leukemia accelerated phase fluorescence in situhybridization

Mesoporous Ternary Nitrides of Earth?Abundant Metals as Oxygen Evolution Electrocatalyst

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Nano-Micro Letters 2020年第6期12卷 190-202页

作者： ali saad Hangjia Shen Zhixing Cheng Ramis Arbi Beibei Guo Lok Shu Hui Kunyu Liang Siqi Liu John Paul Attfield Ayse Turak Jiacheng Wang Minghui Yang Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201Zhejiang ProvincePeople’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Department of Engineering Physics McMaster UniversityHamilton L8S 4L7Canada State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Sciences1295 Dingxi RoadShanghai 200050People’s Republic of China Centre for Science at Extreme Conditions and EaStCHEM School of Chemistry University of EdinburghKings BuildingsWest Mains RoadEdinburgh EH93JJUK

As sustainable energy becomes a major concern for modern society,renewable and clean energy systems need highly active,stable,and low-cost catalysts for the oxygen evolution reaction(OER).Mesoporous materials offer an attractive route for generating efficient electrocatalysts with high mass transport ***,we report an efficient hard templating pathway to design and synthesize three-dimensional(3-D)mesoporous ternary nickel iron nitride(Ni3FeN).The as-synthesized electrocatalyst shows good OER performance in an alkaline solution with low overpotential(259 mV)and a small Tafel slope(54 mV dec?1),giving superior performance to IrO2 and RuO2 *** highly active contact area,the hierarchical porosity,and the synergistic effect of bimetal atoms contributed to the improved electrocatalytic performance toward *** a practical rechargeable Zn–air battery,mesoporous Ni3FeN is also shown to deliver a lower charging voltage and longer lifetime than *** work opens up a new promising approach to synthesize active OER electrocatalysts for energy-related devices.

关键词： Ordered mesoporous structure Hard template Ni3FeN Oxygen evolution reaction Zn–air battery

Study of gonadic growth factors: Seminal transforming growth factor-β1, epidermal growth factor and insulin-like growth factor-I and their relationship with male infertility

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Advances in Reproductive Sciences 2014年第1期2卷 16-23页

作者： Houda Amor Mounir Ajina ali saad Habib Ben ali Laboratoire de Cytogénétique Génétique Moléculaire et Biologie de la Reproduction Humaines CHU Farhat Hached Sousse Tunisie Unité de Médecine de la Reproduction CHU Farhat Hached Sousse Tunisie

Background: The aim of this study was to establish normal reference values for several growth factors in semen and provide a basis for understanding their physiological significance in fertile and infertile subjects. Methods: 110 infertile men semen was evaluated according to WHO standards and by enzyme immunoassay (ELISA kit protocol) to determine the rate of growth factors (TGFβ1, IGFI, EGF). We have also listed neutrophils by staining with peroxidase to examine the association of inflammation with the levels of these factors. The determination of the epididymal (alpha-1,4-glucosidase) marker was directed according to the technical recommended by the WHO in 2010. Each patient received a hormonal balance including the determination of plasma FSH, LH and Testosterone. Results: Concentrations of TGFβ1 were significantly higher in (severe and extreme azoospermic, oligospermic) pathological groups compared to the control group (P 0.05) between control and pathological groups. The IGFI is partly testicular and/or epididymal as it is lowered in some patients with obstructive azoospermia. Positive correlations were observed between the seminal IGFI, mobility (r = 0.487) and sperm morphology (r = +0.187). Immunological sperm abnormalities and/or idiopathic do not alter the rate of EGF seminal. There is no significant correlation between seminal EGF or with sperm parameters or with plasma levels of FSH and LH. Conclusion: The growth factors are primarily peptides, handling and identification in a complex environment as the seminal plasma, but it requires a lot of precautions if we do not want to expose to the risk of bad farms/interpretations of data obtained.

关键词： Infertility Semen EGF IGF-I TGF-β1 FSH LH

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基于卷积神经网络的移动机器人室内物体检测

基于卷积神经网络的移动机器人室内物体检测

作者： SYED saad ali 哈尔滨工业大学

学位级别：硕士

视觉识别技术是机器人能够与人类协同工作的的核心技术之一。过去的计算机视觉系统,在有约束的环境中表现良好,但不适用于复杂多变的工业环境,因此很多任务需要训练有素的工人来完成。近年来,基于机器学习的计算机视觉技术,极大的提升... 详细信息

视觉识别技术是机器人能够与人类协同工作的的核心技术之一。过去的计算机视觉系统,在有约束的环境中表现良好,但不适用于复杂多变的工业环境,因此很多任务需要训练有素的工人来完成。近年来,基于机器学习的计算机视觉技术,极大的提升了现实世界中的自然图像分类的识别率。但是这些方法依赖大量的训练数据(数以百万计的训练图像),需要很长的训练时间(几小时到几天),使这些机器学习算法不适用于实时的通用机器人。本课题使用卷积神经网络进行物体识别任务(识别给定图像中的物体)。为了避免长时间的复杂训练,我们将捕获的图像输入预训练好的卷积神经网络中,并将卷积神经网络的输出作为表征图像中目标的特征向量。首先利用摄像机对目标进行跟踪,再将特征向量序列存储在内存中,最后用支持向量机对特征进行训练,从而实现对目标的分类。支持向量机可以在较短的训练时间内进行训练,从而满足实时性要求。本文测试了上述视觉系统在现实世界室内环境中的识别率。利用摄像机和运动检测,设计的系统可以跟踪在视野中显示的物体。如果用户启动了学习模式,系统将为这个新对象训练一个新的支持向量机。如果用户启动了预测模式,系统会基于已经训练过的模型猜测对象的身份。本文也研究了仅使用视觉反馈对对象进行分类的可能。系统会检查给定对象的特征向量与任何已知的目标特征向量的特征向量之间相似性,相似性通过测量两者之间的欧氏距离得到。最后,我们使用标准数据库测试提出的算法,并与其它数据库对比。

关键词：计算机视觉深度学习对象识别在线学习监督学习

Influence of Implant Location on the Clinical Outcomes of Implant Abutments: A Systematic Review and Meta-analysis

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Influence of Implant Location on the Clinical Outcomes of Im...

作者： Amr Gamal saad ali ElHoussiney 重庆医科大学

学位级别：硕士

Objectives: To compare the failure events and incidence of complications of different abutment materials in anterior and posterior *** was defined as complete loss of the abutment requiring replacement by a new ***: Electronic search using Pub Med/MEDLINE and Google Scholar complemented with hand searches were performed with specific search terms,searches were restricted to publications in English language between January 2006 and March ***: 863 and 1264 implants were inserted in the anterior and posterior regions respectively in a total of 1529 *** titanium abutments failed in anterior or posterior *** the other hand 1.6% of zirconia abutments failed in anterior region and 1.5%failed in posterior *** complications occurred mostly in the posterior region and mostly involving zirconia ***–analysis was only possible for zirconia abutments failure due to considerable heterogeneity of studies and outcome *** significant difference in failure rate was found between anterior and posterior zirconia abutments [Risk ratio（RR）: 1.53;95% confidence interval: 0.49 to 4.77;p=0.47].Conclusion: The systematic review and meta-analysis shows similar outcome of different abutment materials when used in anterior or posterior regions in terms of failure events,biological and esthetic *** only significant finding was the increased incidence of technical complications in the posterior region mostly involving zirconia *** screw loosening was the most common technical complication.

关键词：种植体位置基牙材料临床治疗疗效评价

Quantitative analysis of cefixime via complexation with palladium(Ⅱ) in pharmaceutical formulations by spectrophotometry

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Journal of Pharmaceutical Analysis 2013年第4期3卷 248-256页

作者： Syed Najmul Hejaz Azmi Bashir Iqbal Nada Said Hassan Al-Humaimi Iman Rashid Saif Al-Salmani Noora ali saad Al-Ghafri Nafisur Rahman Department of Applied Sciences Chemistry SectionHigher College of Technology Department of Chemistry Aligarh Muslim University

An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution （pH 3） in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer＇s law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell＇s sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods.

关键词： Spectrophotometry Cefixime Palladium ion Pd(II)-cefixime complex