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Effectiveness of Deep Learning Models for Brain Tumor Classification and Segmentation
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作者 Muhammad Irfan Ahmad Shaf +6 位作者 Tariq Ali umar farooq Saifur Rahman Salim Nasar Faraj Mursal Mohammed Jalalah Samar M.Alqhtani Omar AlShorman 《Computers, Materials & Continua》 SCIE EI 2023年第7期711-729,共19页
A brain tumor is a mass or growth of abnormal cells in the brain.In children and adults,brain tumor is considered one of the leading causes of death.There are several types of brain tumors,including benign(non-cancero... A brain tumor is a mass or growth of abnormal cells in the brain.In children and adults,brain tumor is considered one of the leading causes of death.There are several types of brain tumors,including benign(non-cancerous)and malignant(cancerous)tumors.Diagnosing brain tumors as early as possible is essential,as this can improve the chances of successful treatment and survival.Considering this problem,we bring forth a hybrid intelligent deep learning technique that uses several pre-trained models(Resnet50,Vgg16,Vgg19,U-Net)and their integration for computer-aided detection and localization systems in brain tumors.These pre-trained and integrated deep learning models have been used on the publicly available dataset from The Cancer Genome Atlas.The dataset consists of 120 patients.The pre-trained models have been used to classify tumor or no tumor images,while integrated models are applied to segment the tumor region correctly.We have evaluated their performance in terms of loss,accuracy,intersection over union,Jaccard distance,dice coefficient,and dice coefficient loss.From pre-trained models,the U-Net model achieves higher performance than other models by obtaining 95%accuracy.In contrast,U-Net with ResNet-50 out-performs all other models from integrated pre-trained models and correctly classified and segmented the tumor region. 展开更多
关键词 Brain tumor deep learning ENSEMBLE detection healthcare
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Low-Dimensional Halide Perovskites and Their Advanced Optoelectronic Applications 被引量:12
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作者 Jian Zhang Xiaokun Yang +7 位作者 Hui Deng Keke Qiao umar farooq Muhammad Ishaq Fei Yi Huan Liu Jiang Tang Haisheng Song 《Nano-Micro Letters》 SCIE EI CAS 2017年第3期118-143,共26页
Metal halide perovskites are crystalline materials originally developed out of scientific curiosity. They have shown great potential as active materials in optoelectronic applications. In the last 6 years, their certi... Metal halide perovskites are crystalline materials originally developed out of scientific curiosity. They have shown great potential as active materials in optoelectronic applications. In the last 6 years, their certified photovoltaic efficiencies have reached 22.1%. Compared to bulk halide perovskites, low-dimensional ones exhibited novel physical properties. The photoluminescence quantum yields of perovskite quantum dots are close to 100%. The external quantum efficiencies and current efficiencies of perovskite quantum dot light-emitting diodes have reached 8% and 43 cd A^(-1),respectively, and their nanowire lasers show ultralow-threshold room-temperature lasing with emission tunability and ease of synthesis. Perovskite nanowire photodetectors reached a responsivity of 10 A W^(-1)and a specific normalized detectivity of the order of 10^(12 )Jones. Different from most reported reviews focusing on photovoltaic applications, we summarize the rapid progress in the study of low-dimensional perovskite materials, as well as their promising applications in optoelectronic devices. In particular, we review the wide tunability of fabrication methods and the state-of-the-art research outputs of low-dimensional perovskite optoelectronic devices. Finally, the anticipated challenges and potential for this exciting research are proposed. 展开更多
关键词 Metal halide perovskites Low-dimensional effect SYNTHESIS Optoelectronic devices VERSATILITY
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Fungi as chemical industries and genetic engineering for the production of biologically active secondary metabolites 被引量:7
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作者 Abid Ali Khan Nafees Bacha +3 位作者 Bashir Ahmad Ghosia Lutfullah umar farooq Russell John Cox 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2014年第11期859-870,共12页
Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites.Fungi have been used as tool for producing different types of secondary metabol... Fungi is somewhere in between the micro and macro organisms which is a good source of producing biologically active secondary metabolites.Fungi have been used as tool for producing different types of secondary metabolites by providing different nutrients at different laboratory conditions.The fungi have been engineered for the desired secondary metabolites by using different laboratory techniques,for example,homologous and heterologous expressions.This review reported how the fungi are used as chemical industry for the production of secondary metabolites and how they are engineered in laboratory for the production of desirable metabolites:also the biosynthetic pathways of the bio-organic-molecules were reported. 展开更多
关键词 FUNGI Natural products MICROBIOLOGY Molecular genetics Chemical biology
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Liver bioengineering:Current status and future perspectives 被引量:2
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作者 Christopher Booth Tom Soker +5 位作者 Pedro Baptista Christina L Ross Shay Soker umar farooq Robert J Stratta Giuseppe Orlando 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第47期6926-6934,共9页
The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The fir... The present review aims to illustrate the strategies that are being implemented to regenerate or bioengineer livers for clinical purposes.There are two general pathways to liver bioengineering and regeneration.The first consists of creating a supporting scaffold,either synthetically or by decellularization of human or animal organs,and seeding cells on the scaffold,where they will mature either in bioreactors or in vivo.This strategy seems to offer the quickest route to clinical translation,as demonstrated by the development of liver organoids from rodent livers which were repopulated with organ specific cells of animal and/or human origin.Liver bioengineering has potential for transplantation and for toxicity testing during preclinical drug development.The second possibility is to induce liver regeneration of dead or resected tissue by manipulating cell pathways.In fact,it is well known that the liver has peculiar regenerative potential which allows hepatocyte hyperplasia after amputation of liver volume.Infusion of autologous bone marrow cells,which aids in liver regeneration,into patients was shown to be safe and to improve their clinical condition,but the specific cells responsible for liver regeneration have not yet been determined and the underlying mechanisms remain largely unknown.A complete understanding of the cell pathways and dynamics and of the functioning of liver stem cell niche is necessary for the clinical translation of regenerative medicine strategies.As well,it will be crucial to elucidate the mechanisms through which cells interact with the extracellular matrix,and how this latter supports and drives cell fate. 展开更多
关键词 LIVER Regenerative medicine Tissue engineering Extracellular matrix SCAFFOLD Stem cells
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Single vs dual(en bloc) kidney transplants from donors ≤ 5 years of age: A single center experience 被引量:3
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作者 Yousef Al-Shraideh umar farooq +14 位作者 Hany El-Hennawy Alan C Farney Amudha Palanisamy Jeffrey Rogers Giuseppe Orlando Muhammad Khan Amber Reeves-Daniel William Doares Scott Kaczmorski Michael D Gautreaux Samy S Iskandar Gloria Hairston Elizabeth Brim Margaret Mangus Robert J Stratta 《World Journal of Transplantation》 2016年第1期239-248,共10页
AIM: To compare outcomes between single and dual en bloc(EB) kidney transplants(KT) from small pediatric donors. METHODS: Monocentric nonprospective review of KTs from pediatric donors ≤ 5 years of age. Dual EB KT wa... AIM: To compare outcomes between single and dual en bloc(EB) kidney transplants(KT) from small pediatric donors. METHODS: Monocentric nonprospective review of KTs from pediatric donors ≤ 5 years of age. Dual EB KT was defined as keeping both donor kidneys attached tothe inferior vena cava and aorta, which were then used as venous and arterial conduits for the subsequent transplant into a single recipient. Donor age was less useful than either donor weight or kidney size in decision-making for kidney utilization as kidneys from donors < 8 kg or kidneys < 6 cm in length were not transplanted. Post-transplant management strategies were standardized in all patients.RESULTS: From 2002-2015, 59 KTs were performed including 34 dual EB and 25 single KTs. Mean age of donors(17 mo vs 38 mo, P < 0.001), mean weight(11.0 kg vs 17.4 kg, P = 0.046) and male donors(50% vs 84%, P = 0.01) were lower in the dual EB compared to the single KT group, respectively. Mean cold ischemia time(21 h), kidney donor profile index(KDPI; 73% vs 62%) and levels of serum creatinine(SCr, 0.37 mg/d L vs 0.49 mg/d L, all P = NS) were comparable in the dual EB and single KT groups, respectively. Actuarial graft and patient survival rates at 5-years follow-up were comparable. There was one case of thrombosis resulting in graft loss in each group. Delayed graft function incidence(12% dual EB vs 20% single KT, P = NS) was slightly lower in dual EB KT recipients. Initial duration of hospital stay(mean 5.4 d vs 5.6 d) and the one-year incidences of acute rejection(6% vs 16%), operative complications(3% vs 4%), and major infection were comparable in the dual EB and single KT groups, respectively(all P = NS). Mean 12 mo SCr and abbreviated MDRD levels were 1.17 mg/d L vs 1.35 mg/d L and 72.5 m L/min per 1.73 m^2 vs 60.5 m L/min per 1.73 m^2(both P = NS) in the dual EB and single KT groups, respectively. CONCLUSION: By transplanting kidneys from young pediatric donors into adult recipients, one can effectively expand the limited donor pool and achieve excellent medium-term outcomes. 展开更多
关键词 DONOR age DONOR weight En bloc KIDNEY TRANSPLANT KIDNEY DONOR profile index SINGLE KIDNEY TRANSPLANT Small PEDIATRIC DONOR
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A Composite State Convergence Scheme for Bilateral Teleoperation Systems 被引量:1
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作者 Muhammad Usman Asad umar farooq +3 位作者 Jason Gu Ghulam Abbas Rong Liu Valentina E.Balas 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1166-1178,共13页
State convergence is a novel control algorithm for bilateral teleoperation of robotic systems. First, it models the teleoperation system on state space and considers all the possible interactions between the master an... State convergence is a novel control algorithm for bilateral teleoperation of robotic systems. First, it models the teleoperation system on state space and considers all the possible interactions between the master and slave systems. Second, it presents an elegant design procedure which requires a set of equations to be solved in order to compute the control gains of the bilateral loop. These design conditions are obtained by turning the master-slave error into an autonomous system and imposing the desired dynamic behavior of the teleoperation system. Resultantly, the convergence of master and slave states is achieved in a well-defined manner. The present study aims at achieving a similar convergence behavior offered by state convergence controller while reducing the number of variables sent across the communication channel. The proposal suggests transmitting composite master and slave variables instead of full master and slave states while keeping the operator's force channel intact. We show that,with these composite and force variables;it is indeed possible to achieve the convergence of states in a desired way by strictly following the method of state convergence. The proposal leads to a reduced complexity state convergence algorithm which is termed as composite state convergence controller. In order to validate the proposed scheme in the absence and presence of communication time delays, MATLAB simulations and semi-real time experiments are performed on a single degree-of-freedom teleoperation system. 展开更多
关键词 COMPOSITE VARIABLES linear control SYSTEMS STATE CONVERGENCE TELEOPERATION time delay
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Application of improved BPNN in image restoration-learning coefficient
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作者 umar farooq 沈庭芝 +3 位作者 Muhammad Imran 赵三元 Sadia Murawwat 王清云 《Journal of Beijing Institute of Technology》 EI CAS 2012年第4期543-546,共4页
A new method of artificial intelligence based on a new improved back propagation neural network (BPNN) algorithm is partially applied in the problem of image restoration. In order to over- come the inherited issues ... A new method of artificial intelligence based on a new improved back propagation neural network (BPNN) algorithm is partially applied in the problem of image restoration. In order to over- come the inherited issues in conventional back propagation algorithm i.e. slow convergence rate, longer training time, hard to achieve global minima etc. , different methods have been used including the introduction of dynamic learning rate and dynamic momentum coefficient etc. With the passage of time different techniques has been used to improve the dynamicity of these coefficients. The meth- od applied in this paper improves the effect of learning coefficient η by using a new way to modify the value dynamically during learning process. The experimental results show that this helps in im- proving the efficiency overall both in visual effect and quality analysis. 展开更多
关键词 image restoration image processing INTELLIGENT back propagation neural network(BPNN) dynamic learning coefficient
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Structural Evolution and Electronic Properties of Au2Gen-/0(n=1-8) Clusters: Anion Photoelectron Spectroscopy and Theoretical Calculations
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作者 Sheng-Jie Lu Hong-Guang Xu +1 位作者 Xi-Ling Xu Wei-Jun Zheng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第2期229-240,I0003,共13页
Investigating the structures and properties of Au-Ge mixed clusters can give insight into the microscopic mechanisms in gold-catalyzed Ge films and can also provide valuable information for the production of germanium... Investigating the structures and properties of Au-Ge mixed clusters can give insight into the microscopic mechanisms in gold-catalyzed Ge films and can also provide valuable information for the production of germanium-based functional materials. In this work, size-selected anion photoelectron spectroscopy and theoretical calculations were used to explore the structural evolution and electronic properties of Au2Gen^-/0 (n=1-8) clusters. It is found that the two Au atoms in Au2Gen^-/0 (n=1-8) showed high coordination numbers and weak aurophilic interactions. The global minima of Au2Gen- anions and Au2Gen neutrals are in spin doublet and singlet states, respectively. Au2Gen- anions and Au2Gen neutrals showed similar structural features, except for Au2Ge4^-/0 and Au2Ge5^-/0. The C2v symmetric V-shaped structure is observed for Au2Ge1^-/0, while Au2Ge2^-/0 has a C2v symmetric dibridged structure. Au2Ge3^-/0 can be viewed as the two Au atoms attached to different Ge-Ge bonds of Ge3 triangle. Au2Ge4- has two Au atoms edge-capping Ge4 tetrahedron, while Au2Ge4 neutral adopts a C2v symmetric double Au atoms face-capping Ge4 rhombus. Au2Ge5-8^-/0 show triangular, tetragonal, and pentagonal prism-based geometries. Au2Ge6 adopts a C2v symmetric tetragonal prism structure and exhibits σ plus π double bonding characters. 展开更多
关键词 Photoelectron spectroscopy Transition metal Germanium cluster Structural evolution Quantum chemical calculations
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A Smart Wellness Service Platform and Its Practical Implementation
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作者 umar farooq Intae Ryoo Gon Khang 《Computers, Materials & Continua》 SCIE EI 2021年第1期45-57,共13页
Advances in the field of medical sciences and medical technology,and present-day challenges,such as an aging population,rising medical expenses,and lifestyle-related diseases,have collectively catalyzed a research eco... Advances in the field of medical sciences and medical technology,and present-day challenges,such as an aging population,rising medical expenses,and lifestyle-related diseases,have collectively catalyzed a research ecosystem termed“smart wellness.”This article describes the establishment of a smart wellness service platform designed to empower individuals to create a sense of balance in their lives.Step-by-step details include service model,design,and architectural considerations.As a proof of concept,implementation details of a Health Improvement and Management Systems(HIMS)Hub,a Smart Wellness Service Platform deployed in six cities in South Korea,are presented.An on-site survey conducted in Busan Metropolitan City reveals the percentage of satisfied users to be 91.3%.Furthermore,data gathered from 27,236 physical evaluations of users from a Busan city center over the period of April 2013 to May 2018 reveal that males and females in their 50s and 60s account for the highest number of participants,while males in their 70s have a higher rate of participation than females in the same age group. 展开更多
关键词 WELLNESS smart wellness smart wellness service platform u-Healthcare sports and exercise medicine
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Greyscale based learning in BPNN for image restoration problem
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作者 umar farooq 闫雪梅 +1 位作者 SADIA Murawwat MUHAMMAD Imran 《Journal of Beijing Institute of Technology》 EI CAS 2013年第1期94-100,共7页
A new method of back propagation learning with respect to the problem of image restora- tion which is named as greyscale based learning in back propagation neural networks (BPNN) is in- vestigated. It is observed th... A new method of back propagation learning with respect to the problem of image restora- tion which is named as greyscale based learning in back propagation neural networks (BPNN) is in- vestigated. It is observed that by using this method the value of mean square error (MSE) decreases significantly. In addition, this method also gives good visual results when it is applied in image resto- ration problem. This method is also useful to tackle the inherited drawback of falling into local mini- ma by reducing its effect on overall system by bifurcating the learning locally different for different grey scale values. The performance of this algorithm has been studied in detail with different combi- nations of weights. In short, this algorithm provides much better results especially when compared with the simple back propagation algorithm with any further enhancements and without going for hy- brid solutions. 展开更多
关键词 greyscale based learning back propagation neural network(BPNN) image restoration
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Occurrence of Root-Knot and Reniform Nematodes in Ornamental Plants Grown in Aligarh Muslim University Campus, India
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作者 Aasia Rashid Bhat Tabreiz Ahmed Khan umar farooq 《American Journal of Plant Sciences》 2014年第13期1885-1888,共4页
An extensive survey of about 50 ornamental plants growing in A.M.U. campus were carried out to find out the infection of root-knot (Meloidogyne spp.) and reniform nematodes (Rotylenchulus reniformis). Out of 50 specie... An extensive survey of about 50 ornamental plants growing in A.M.U. campus were carried out to find out the infection of root-knot (Meloidogyne spp.) and reniform nematodes (Rotylenchulus reniformis). Out of 50 species of ornamental plants studied, 29 species of these plants were found to be infected with root-knot nematodes (Meloidogyne spp.) and 15 species were infected with reniform nematode (Rotylenchulus reniformis). The highest percentage of infection of root-knot nematodes was observed in Impatiens balsamina (100%) and reniform nematode was observed in Hibiscus rosa-sinensis (56%). Among the Meloidogyne spp. the highest percentage of infection of M. incognita was observed in Pseuderanthemum atropurpureum (80%) whereas, the highest percentage of infection of M. javanica and M. arenaria was observed in Mirabilis jalapa (72%) and Celosis cristata (28%). 展开更多
关键词 ROOT-KNOT NEMATODE Reniform NEMATODE ORNAMENTAL Plants
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Profiles of energy metabolites and haptoglobin in dairy cows under organic management in Alberta farms
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作者 John F. Odhiambo umar farooq +4 位作者 Summera Iqbal Dominik Mansmann Qendrim Zebeli Suzanna M. Dunn Burim N. Ametaj 《Open Journal of Animal Sciences》 2013年第2期105-113,共9页
Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at... Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at the University of Alberta dairy farm. Blood samples were collected during the following periods: Dry, 0 - 30, 30 - 60, and 60 - 90 days in milk (DIM, n = 7 cows). Concentrations of metabolites were evaluated by enzymatic colorimetric methods. Concentrations of Hp were determined by bovine ELISA kits. Data were analyzed by the mixed procedures of SAS. Concentrations of NEFA and BHBA in blood were elevated (P < 0.001) 0 to 30 d, intermediate 30 to 60, and 60 to 90 d, and lower in the dry period. In addition, BHBA was higher (P < 0.0001) at all stages of lactation in conventional than organic cows (e.g. 1289.4 ± 88.6 vs. 883.6 ± 47.5 μmol/L in conventional and organic cows at 0 - 30 d, respectively). Serum concentrations of cholesterol increased with increasing DIM and returned to nadir levels during dry period and was higher (P < 0.0001) in conventional than organic cows. Low glucose concentrations were observed 0 to 30 d, levels were intermediate 30 to 60 and 60 to 90 d, and peaked during the dry period (P < 0.54) between conventional and organic cows. Lactate did not (P < 0.24) vary with DIM or day × farm type but was higher (P < 0.0001) in organic cows than in conventional cows. Serum concentrations of Hp were elevated during dry period;reached peak levels 0 to 30 d and decreased gradually with increasing days postpartum and were much higher at all periods in conventional than organic cows. Overall, concentrations of Hp were 528.1 ± 45.2 μg/mL in conventional cows vs. 261.1 ± 16.9 μg/mL in organic cows (P < 0.0001). Taken together, these data indicate that metabolic changes associated with initiation of lactation are preceded by an acute phase response in dairy cows, and that cows in organic systems seem to be healthier than cows under conventional systems. These differences might be due to differences in nutritional management in the two systems. 展开更多
关键词 ORGANIC COWS BHBA NEFA HAPTOGLOBIN
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Catalytic Reduction of Coomassie Brilliant Blue R-250 by Silver Nanomagnetic Clusters
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作者 Madiha Ishaq umar farooq +1 位作者 Muhammad Salman Muhammad Makhshoof Athar 《材料科学与工程(中英文B版)》 2021年第1期28-41,共14页
The research work represents the synthesis of silver nanoparticles(AgNPs)coated on magnetic iron oxide nanoparticles by chemical reduction and co-precipitation method,respectively.AgNPs were coated on magnetic ironoxi... The research work represents the synthesis of silver nanoparticles(AgNPs)coated on magnetic iron oxide nanoparticles by chemical reduction and co-precipitation method,respectively.AgNPs were coated on magnetic ironoxide nanoparticles to form Ag@Fe3O4.AgNPs were characterized by UV-Visible spectroscopy.The magnetic nanoparticles(MNPs)and magnetic nanoclusters(MNC)were characterized by Fourier transform infra red(FTIR)spectroscopy.Bulk density,moisture content and ash content were also determined.These MNCs were used for the reduction of 4-nitrophenol(4-NP)and coomassie Brilliant Blue R-250(CBBR-250).The parameters such as effect of time,catalyst dosage,concentration of sodium borohydride and concentration of 4-NP and dye were studied.It was found that the catalytic reduction of 4-NP and dye were in 20 minutes by MNCs.Kinetic analysis shows that the pseudo-first-order was found to be linear.It revealed that the use of these MNCs can be considered as a reliable method for the catalytic reduction studies. 展开更多
关键词 AGNPS MNCS catalytic reduction 4-NP CBBR-250.
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Bioassay-guided isolation of novel and selective urease inhibitors from Diospyros lotus 被引量:3
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作者 Abdur Rauf Ghias Uddin +5 位作者 Bina S. Siddiqui Ajmal Khan umar farooq Farhan A. Khan Syed Majid Bukhari Sher Bahadar Khan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2017年第11期865-870,共6页
Two new dimeric naphthoquinones, 5′,8′-dihydroxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(1; Di-naphthodiospyrol D) and 5′,8′-dihydroxy-5,8-dimethoxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraon... Two new dimeric naphthoquinones, 5′,8′-dihydroxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(1; Di-naphthodiospyrol D) and 5′,8′-dihydroxy-5,8-dimethoxy-6,6′-dimethyl-7,3′-binaphthyl-1,4,1′,4′-tetraone(2; Di-naphthodiospyrol E), along with known naphthoquinones diospyrin(3) and 8-hydroxy diospyrin(4) were isolated from the chloroform fraction of extract of Diospyros lotus roots. Their structures were elucidated by advanced spectroscopic analyses, including HSQC, HMBC, NOESY, and J-resolved NMR experiments. The fractions and compounds 1-4 were evaluated for urease activity and phosphodiesterase-Ⅰ, carbonic anhydrase-Ⅱ and α-chymotrypsin enzyme inhibitory activities. Compounds 1 and 2 and their corresponding fractions showed significant and selective inhibitory effects on urease activities. The IC_(50) values of 1 and 2 were 260.4 ± 6.37 and 381.4 ± 4.80 μmol·L-1, respectively, using thiourea(IC_(50) = 21 ± 0.11 μmol·L^(-1)) as the standard inhibitor. This was the first report demonstrating that the naphthoquinones class showed urease inhibition. 展开更多
关键词 DIOSPYROS lotus NAPHTHOQUINONES Phosphodiesterase-Ⅰ Carbonic anhydrase-Ⅱ Α-CHYMOTRYPSIN UREASE inhibitory activities
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Sedative and antinociceptive activities of two new sesquiterpenes isolated from Ricinus communis 被引量:2
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作者 umar farooq Ajmal Khan +5 位作者 Sadia Naz Abdur Rauf Haroon Khan Afsar Khan Irfan Ullah Syed Majid Bukhari 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2018年第3期225-230,共6页
Two new sesquiterpenes, trivially named ricinusoids A(1) and ricinusoids B(2), were isolated from ethyl acetate fraction of Ricinus communis. The structures of new compounds were elucidated by detailed spectroscopic t... Two new sesquiterpenes, trivially named ricinusoids A(1) and ricinusoids B(2), were isolated from ethyl acetate fraction of Ricinus communis. The structures of new compounds were elucidated by detailed spectroscopic techniques, including 1 D-and 2 D-NMR, UV, IR spectroscopy, and mass spectrometry. The compounds(1-2) were also assessed for in-vivo sedative and analgesic like effects in open field and acetic acid induced writhing tests respectively at 5, 10, and 20 mg·kg^(–1) i.p. Pretreatment of both test compounds caused significant(P ≤ 0.05) reduction in locomotive activity like sedative agents and abdominal constrictions like analgesics. Both compounds(1-2) possessed marked sedative and antinociceptive effects in animal models. 展开更多
关键词 Ricinus communis SESQUITERPENOIDS EUPHORBIACEAE Spectroscopic techniques Antinociceptive activity
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Three new anthraquinone derivatives isolated from Symplocos racemosa and their antibiofilm activity
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作者 umar farooq Sara Khan +9 位作者 Sadia Naz Ajmal Khan Afsar Khan Ayaz Ahmed Abdur Rauf Syed Majid Bukhari Shujaat Ali Khan Arfa Kamil Nadia Riaz Abdur Rahman Khan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2017年第12期944-949,共6页
Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C(Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of exte... Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C(Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses(UV, IR, Mass, ~1 H-and ^(13)C-NMR, and two-dimensional(2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·m L^(-1) against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae. 展开更多
关键词 SYMPLOCOS racemosa SUBSTITUTED ANTHRAQUINONE ANTIBIOFILM activity
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治理和税收:外国援助是否重要?
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作者 温军 乌马尔·法鲁克 +4 位作者 摩撒·塔巴什 加勒布·艾尔·拉法 比拉尔·海德尔·苏哈尼 吴雨晨(译) 孙彩红(审校) 《国际行政科学评论(中文版)》 2023年第1期307-329,共23页
本文旨在探究治理、外国援助和税收之间的关系。一般认为,治理是一个多面性因素,可能受到外国援助等其他因素的影响。外国援助会阻碍治理状况,从而减少税收。为了检验上述理论假设,本研究收集了一些亚洲经济体2001—2019年的数据,并采... 本文旨在探究治理、外国援助和税收之间的关系。一般认为,治理是一个多面性因素,可能受到外国援助等其他因素的影响。外国援助会阻碍治理状况,从而减少税收。为了检验上述理论假设,本研究收集了一些亚洲经济体2001—2019年的数据,并采用面板FMOLS(完全修正的最小二乘法)检验来估计回归状况。实证结果起初显示治理和外国援助在长期内都与税收成正相关。然而,在外国援助和治理的相互作用下,税收出现了负相关趋势。外国援助恶化了治理状况,对税收产生了负面的溢出效应。实证分析表明,公共政策官员应该专注于治理并判断外国援助的有效性,以达到增加税收的目标。 展开更多
关键词 亚洲经济体 协整分析 外国援助 治理 税收
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