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The roles of MAPKs in disease 被引量:65
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作者 Michael C Lawrence arif Jivan Chunli Shao Lingling Duan Daryl Goad Elma Zaganjor Jihan Osborne Kathleen McGlynn Steve Stippec Svetlana Earnest Wei Chen Melanie H Cobb 《Cell Research》 SCIE CAS CSCD 2008年第4期436-442,共7页
MAP kinases transduce signals that are involved in a multitude of cellular pathways and functions in response to a variety of ligands and cell stimuli. Aberrant or inappropriate functions of MAPKs have now been identi... MAP kinases transduce signals that are involved in a multitude of cellular pathways and functions in response to a variety of ligands and cell stimuli. Aberrant or inappropriate functions of MAPKs have now been identified in diseases ranging from cancer to inflammatory disease to obesity and diabetes. In many cell types, the MAPKs ERK1/2 are linked to cell proliferation. ERK1/2 are thought to play a role in some cancers, because mutations in Ras and B-Raf, which can activate the ERK1/2 cascade, are found in many human tumors. Abnormal ERK1/2 signaling has also been found in polycystic kidney disease, and serious developmental disorders such as cardio-facio-cutaneous syndrome arise from mutations in components of the ERK1/2 cascade. ERK1/2 are essential in well-differentiated cells and have been linked to long-term potentiation in neurons and in maintenance of epithelial polarity. Additionally, ERK1/2 are important for insulin gene transcription in pancreatic beta cells, which produce insulin in response to increases in circulating glucose to permit efficient glucose utilization and storage in the organism. Nutrients and hormones that induce or repress insulin secretion activate and/or inhibit ERK1/2 in a manner that reflects the secretory demand on beta cells. Disturbances in this and other regulatory pathways may result in the contribution of ERK1/2 to the etiology of certain human disorders. 展开更多
关键词 cancer polycystic kidney disease docking motifs Mxi2 insulin gene transcription PEA-15 CHOP
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Correlation of p53 over-expression and alteration in p53 gene detected by polymerase chain reaction-single strand conformation polymorphism in adenocarcinoma of gastric cancer patients from India 被引量:28
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作者 Sajjad Karim arif Ali 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第11期1381-1387,共7页
AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters. METHODS: A total of 103 gastric cancer patients were included in ... AIM: To study the alterations in p53 gene among Indian gastric cancer patients and to correlate them with the various clinicopathological parameters. METHODS: A total of 103 gastric cancer patients were included in this study. The p53 alterations were studied by both immunohistochemical method as well as polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. We only studied four (exon 5, 6, 7, and 8) of the 11 ,p53 exons. The alterations in p53 were also correlated with respect to various clinicopathological parameters. RESULTS: Among 103 cases, p53 over-expression and alteration were detected in 37 (35.92%) and 19 (18.44%) cases, respectively. Most of the ,p53 alterations were found at exon 5 (31.54%), followed by exon 6 (26.31%), exon 7 (21.04%) and exon 8 (21.04%). A significant correlation of p53 overexpression was found with p53 alteration (P = 0.000). Concordance between ,p53 alteration (as detected by SSCP) and over-expression [as detected by immunohistochemistry (IHC)] was found in 75% cases. We found that IHC-positive/SSCP-negative cases accounted for 21% of cases and IHC-negative/SSCP- positive cases accounted for remaining 4% cases. CONCLUSION: Our results show that p53 gene mutations are significantly correlated with p53 protein over-expression, with 75% concordance in over-expression and alteration in the p53 gene, but 25% disconcordance also cautions against the assumption that p53 over-expression is always associated with a gene mutation. There may be other mechanisms responsible for stabilization and accumulation of p53 protein with no evidence of gene mutation that reflect an accumulation of a non-mutated protein, or a false negative SSCP result. 展开更多
关键词 Gastric cancer P53 Single strandconformation polymorphism Gene mutation Immunohistochemistry
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中国棉铃虫核型多角体病毒几丁质酶基因的定位与克隆 被引量:16
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作者 彭辉银 李星 +3 位作者 张双民 Basil M.arif 陈新文 胡志红 《中国病毒学》 CSCD 1998年第2期139-143,共5页
以α32PdATP标记含CfMNPV几丁质酶基因的重组质粒为探针,在68℃条件下对棉铃虫单粒包埋核型多角体病毒(HaSNPV)进行Southern杂交,将HaSNPV的几丁质酶基因分别定位在BamHIE、BglⅡ... 以α32PdATP标记含CfMNPV几丁质酶基因的重组质粒为探针,在68℃条件下对棉铃虫单粒包埋核型多角体病毒(HaSNPV)进行Southern杂交,将HaSNPV的几丁质酶基因分别定位在BamHIE、BglⅡE、EcoRIG、HindⅢF、XbaIH、BamHI+HindIIM和BamHI+XbaIH,并以pTZ19R为载体获得了XbaIH片段克隆。 展开更多
关键词 棉铃虫 核型多角体病毒 几丁质酶 基因定位
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洱海流域不同施肥模式对稻田氮磷径流流失的影响 被引量:19
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作者 姜海斌 沈仕洲 +5 位作者 谷艳茹 于双 邹洪涛 arif Husain 张磊 张克强 《农业环境科学学报》 CAS CSCD 北大核心 2021年第6期1305-1313,共9页
为探究洱海流域水稻种植的合理施肥模式,减少稻田氮磷径流流失,通过田间小区试验,研究不同施肥模式对稻田氮磷径流流失和水稻产量的影响。结果表明:与常规施肥处理(CF)相比,化肥减量20%处理(T1)总氮径流流失量无显著差异,有机肥替代处理... 为探究洱海流域水稻种植的合理施肥模式,减少稻田氮磷径流流失,通过田间小区试验,研究不同施肥模式对稻田氮磷径流流失和水稻产量的影响。结果表明:与常规施肥处理(CF)相比,化肥减量20%处理(T1)总氮径流流失量无显著差异,有机肥替代处理(T2~T5)总氮径流流失量降低31.6%~40.4%,缓控释肥处理(T6)总氮径流流失量降低15.7%;与CF处理相比,T1、T2和T6处理总磷径流流失量无显著差异,T3和T5处理总磷径流流失量分别降低23.3%和17.4%,T4处理总磷流失量增加57.0%。与CF处理相比,T6处理和T1处理籽粒产量无显著差异,T2~T5处理籽粒产量降低11.8%~42.9%;与T1处理相比,T5和T3处理籽粒产量无显著差异。与CF处理相比,T1、T6和T4处理秸秆产量无显著差异,T2、T3和T5处理秸秆产量分别降低15.5%、16.0%和36.0%。综合考虑不同施肥处理的稻田径流流失量和水稻产量等因素,化肥减量(T1)、有机无机配施(T3和T5)和缓控释肥(T6)处理是可供选择的环境友好型施肥模式。 展开更多
关键词 洱海流域 施肥模式 稻田 径流 氮磷流失 产量
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旋转状态下风机叶片雷击接闪特性的实验研究 被引量:15
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作者 郭子炘 李庆民 +5 位作者 于万水 张黎 王国政 马宇飞 WAQAS arif SIEW Wah Hoon 《中国电机工程学报》 EI CSCD 北大核心 2018年第16期4951-4959,共9页
风机雷击事故频发,严重威胁风电场正常运行。现场观测数据表明,旋转风机更易遭受雷击。对此该文设计1:30缩比可旋转3MW风机模型,模拟真实风机旋转叶尖线速度,使用正负极性标准操作波,利用长间隙放电模拟真实雷电,开展旋转状态下风机叶... 风机雷击事故频发,严重威胁风电场正常运行。现场观测数据表明,旋转风机更易遭受雷击。对此该文设计1:30缩比可旋转3MW风机模型,模拟真实风机旋转叶尖线速度,使用正负极性标准操作波,利用长间隙放电模拟真实雷电,开展旋转状态下风机叶片防雷装置接闪特性研究。实验结果表明,旋转会对接闪过程中叶片接闪点分布与接闪后放电通道产生影响,放电具有明显的极性效应。旋转使得正极性放电下叶片接闪器拦截效率下降;对负极性影响较小。正极性放电更易击中远离叶尖部位。成功接闪后,接闪点附近放电通道因叶片旋转发生偏移,产生"拉弧"现象,造成叶片损伤,并与实际风机受损情况相对应。所得结果为风机叶片防雷优化设计提供参考。 展开更多
关键词 风机叶片 旋转 雷击接闪 雷击防护 接闪器 极性效应
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Effect of precut sphincterotomy on post-endoscopic retrograde cholangiopancreatography pancreatitis:A systematic review and meta-analysis 被引量:13
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作者 Abhishek Choudhary Jessica Winn +6 位作者 Sameer Siddique Murtaza arif Zainab arif Ghassan M Hammoud Srinivas R Puli Jamal A Ibdah Matthew L Bechtold 《World Journal of Gastroenterology》 SCIE CAS 2014年第14期4093-4101,共9页
AIM: To conduct a systemic review and meta-analysis to investigate the role of early precut technique. Multiple randomized controlled trails (RCTs) have reported conflicting results of the early precut sphincterotomy.
关键词 Early precut Endoscopic retrograde cholangiopancreatography cannulation Post-endoscopic retrograde cholangiopancreatography pancreatitis Randomized controlled trials META-ANALYSIS
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Survey on synchrophasor data quality and cybersecurity challenges, and evaluation of their interdependencies 被引量:13
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作者 Aditya SUNDARARAJAN Tanwir KHAN +1 位作者 Amir MOGHADASI arif I.SARWAT 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2019年第3期449-467,共19页
Synchrophasor devices guarantee situation awareness for real-time monitoring and operational visibility of smart grid. With their widespread implementation,significant challenges have emerged, especially in communicat... Synchrophasor devices guarantee situation awareness for real-time monitoring and operational visibility of smart grid. With their widespread implementation,significant challenges have emerged, especially in communication, data quality and cybersecurity. The existing literature treats these challenges as separate problems,when in reality, they have a complex interplay. This paper conducts a comprehensive review of quality and cybersecurity challenges for synchrophasors, and identifies the interdependencies between them. It also summarizes different methods used to evaluate the dependency and surveys how quality checking methods can be used to detect potential cyberattacks. 展开更多
关键词 SYNCHROPHASOR Data quality CYBERSECURITY METHODOLOGY
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Stochastic Numerical Analysis for Impact of Heavy Alcohol Consumption on Transmission Dynamics of Gonorrhoea Epidemic 被引量:12
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作者 Kamaleldin Abodayeh Ali Raza +3 位作者 Muhammad Shoaib arif Muhammad Rafiq Mairaj Bibi Muhammad Mohsin 《Computers, Materials & Continua》 SCIE EI 2020年第3期1125-1142,共18页
This paper aims to perform a comparison of deterministic and stochastic models.The stochastic modelling is a more realistic way to study the dynamics of gonorrhoea infection as compared to its corresponding determinis... This paper aims to perform a comparison of deterministic and stochastic models.The stochastic modelling is a more realistic way to study the dynamics of gonorrhoea infection as compared to its corresponding deterministic model.Also,the deterministic solution is itself mean of the stochastic solution of the model.For numerical analysis,first,we developed some explicit stochastic methods,but unfortunately,they do not remain consistent in certain situations.Then we proposed an implicitly driven explicit method for stochastic heavy alcohol epidemic model.The proposed method is independent of the choice of parameters and behaves well in all scenarios.So,some theorems and simulations are presented in support of the article. 展开更多
关键词 Heavy alcohol model stochastic techniques stability analysis
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Rotator cuff tears: An evidence based approach 被引量:12
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作者 Senthil Nathan Sambandam Vishesh Khanna +1 位作者 arif Gul Varatharaj Mounasamy 《World Journal of Orthopedics》 2015年第11期902-918,共17页
Lesions of the rotator cuff(RC) are a common occurrence affecting millions of people across all parts of the globe. RC tears are also rampantly prevalent with an agedependent increase in numbers. Other associated fact... Lesions of the rotator cuff(RC) are a common occurrence affecting millions of people across all parts of the globe. RC tears are also rampantly prevalent with an agedependent increase in numbers. Other associated factors include a history of trauma, limb dominance, contralateral shoulder, smoking-status, hypercholesterolemia, posture and occupational dispositions. The challenge lies in early diagnosis since a high proportion of patients are asymptomatic. Pain and decreasing shoulder power and function should alert the heedful practitioner in recognizing promptly the onset or aggravation of existing RC tears. Partial-thickness tears(PTT) can be bursalsided or articular-sided tears. Over the course of time, PTT enlarge and propagate into full-thickness tears(FTT) and develop distinct chronic pathological changes due to muscle retraction, fatty infiltration and muscle atrophy. These lead to a reduction in tendon elasticity and viability. Eventually, the glenohumeral joint experiences a series of degenerative alterations- cuff tear arthropathy. To avert this, a vigilant clinician must utilize and corroborate clinical skill and radiological findings to identify tear progression. Modern radio-diagnostic means of ultrasonography and magnetic resonance imaging provide excellent visualization of structural details and are crucial in determining further course of action for these patients. Physical therapy along with activity modifications, antiinflammatory and analgesic medications form the pillars of nonoperative treatment. Elderly patients with minimal functional demands can be managed conservatively and reassessed at frequent intervals. Regular monitoring helps in isolating patients who require surgical interventions. Early surgery should be considered in younger, active and symptomatic, healthy patients. In addition to being costeffective, this helps in providing a functional shoulder witha stable cuff. An easily reproducible technique of maximal strength and sturdiness should by chosen among the armamentarium of the 展开更多
关键词 ROTATOR CUFF TEARS Partial thickness TEARS Full thickness TEAR Natural history Ultrasonography Magnetic resonance imaging Single ROW REPAIR Double ROW REPAIR Healing
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Numerical simulation to evaluate gas diffusion of turbulent flow in mine ventilation system 被引量:11
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作者 arif Widiatmojo Kyuro Sasaki +4 位作者 Nuhindro Priagung Widodo Yuichi Sugai Johannes Sinaga Haris Yusuf 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期349-355,共7页
Tracer gas technique is a method to analyze the airflow path, measure the airflow quantity, and detect any recirculation or leakages in underground mine. In addition, it is also possible to evaluate the axial gas diff... Tracer gas technique is a method to analyze the airflow path, measure the airflow quantity, and detect any recirculation or leakages in underground mine. In addition, it is also possible to evaluate the axial gas diffusion of gas in turbulent bulk flow by utilizing the tracer gas data. This paper discussed about the measurement using tracer gas technique in Cibaliung Underground Mine, Indonesia and the evaluation of effective axial diffusion coefficient, E, by numerical simulation. In addition, a scheme to treat network flow in mine ventilation system was also proposed. The effective axial diffusion coefficient for each airway was evaluated based on Taylor's theoretical equation. It is found that the evaluated diffusion coefficient agrees well with Taylor's equation by considering that the wall friction factor, f, is higher than those for smooth pipe flow. It also shows that the value of effective diffusion coefficient can be inherently determined and the value is constant when matching with other measurements. Furthermore, there are possibilities to utilize the tracer gas measurement data to evaluate the airway friction factors. 展开更多
关键词 Tracer gas Effective axial diffusion coefficient Mine ventilation Numerical simulation
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Deciphering codon usage patterns and evolutionary forces in chloroplast genes of Camellia sinensis var. assamica and Camellia sinensis var. sinensis in comparison to Camellia pubicosta 被引量:9
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作者 Sophiarani Yengkhom arif Uddin Supriyo Chakraborty 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2771-2785,共15页
Codon usage bias(CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast(cp) gene... Codon usage bias(CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast(cp) genes among three tea species, i.e., Camellia sinensis var. assamica(Assam tea), Camellia sinensis var. sinensis(Chinese tea) and Camellia pubicosta(wild tea species) as no work on CUB was reported earlier. To understand the patterns of codon usage among the cp genes of three tea groups, we used bioinformatic tools to investigate the protein coding sequences of cp genes. In our present study, the mean nucleobase T was the highest whereas C was the lowest in all the three tea groups. The overall AT content was more than GC content, i.e., genes were AT rich. The scaled chi-square(SCS) value indicated that the CUB of cp genes was low. The codon CGT(Arg) was over-represented in C. sinensis var. sinensis whereas GGA(Pro) was over-represented in C. pubicosta species. Heatmap study revealed that most of the GC ending codons showed positive correlations between codon usage and GC3 while AT ending codons exhibited negative correlations. From neutrality plot analysis, it was evident that natural selection had played a major role, while mutation pressure exerted a minor effect in the CUB of cp genes in three tea groups. Highly significant(P<0.01) positive correlation was found between SCS and synonymous codon usage order(SCUO) of cp genes which suggested that high expression of cp genes was associated with high degree of CUB. 展开更多
关键词 CAMELLIA SINENSIS var.assamica CAMELLIA SINENSIS var.sinensis CAMELLIA pubicosta CHLOROPLAST genes CODON usage bias mutation natural selection
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Acute Lymphoblastic Leukemia Presenting as Systemic Juvenile Idiopathic Arthritis: Experience from Bangladesh
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作者 Manik Kumar Talukder Kamrul Laila +6 位作者 Md. arif Hossain Md. Shafiqul Islam Md. Zahidul Islam Kalyan Benjamin Gomes Mujammel Haque Md. Mahbubul Islam Md. Imnul Islam 《Open Journal of Rheumatology and Autoimmune Diseases》 2024年第1期1-12,共12页
Background: Acute lymphoblastic leukemia (ALL), the most common paediatric malignancy, is a heterogeneous hematologic disease. ALL patients may present with isolated and persistent osteo-articular complaints, lower in... Background: Acute lymphoblastic leukemia (ALL), the most common paediatric malignancy, is a heterogeneous hematologic disease. ALL patients may present with isolated and persistent osteo-articular complaints, lower incidence of hepatomegaly, splenomegaly or lymphadenopathy without clear laboratory features, and misdiagnosed as systemic juvenile idiopathic arthritis (sJIA). Methods: This was a single center cross sectional study over a period of 4 years. Clinic laboratory profiles of 39 ALL children were compared with 39 age and sex-matched sJIA cases. Result: Among 39 ALL patients 89.7% were initially misdiagnosed as sJIA upon clinical presentation. Majority (66.7%) of ALL patients had oligo-articular joint involvement. In sJIA, small joints of the hands were most commonly involved. The total WBC count was significantly higher in ALL patients (p-value 0.0065). CRP and LDH values between the two groups showed significant differences (p-value 0.00006 and 0.00001 respectively). Conclusion: The presentation of leukemia with arthralgia or arthritis makes the diagnosis difficult for the physicians. The diagnosis of sJIA must be made with caution keeping the possibility of haematological malignancy in mind. 展开更多
关键词 ALL sJIA ARTHRITIS ARTHRALGIA MUSCULOSKELETAL
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Analysis of the Fertilizing and Bioremediation Potential of Leaf Litter Compost Amendment in Different Soils through Indexing Method
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作者 Sophayo Mahongnao Pooja Sharma +1 位作者 arif Ahamad Sarita Nanda 《Journal of Environmental Protection》 2024年第3期265-297,共33页
This research study explored the efficacy of leaf litter compost as a sustainable soil amendment with the objective of promoting soil health and mitigating the accumulation of potentially toxic elements. The investiga... This research study explored the efficacy of leaf litter compost as a sustainable soil amendment with the objective of promoting soil health and mitigating the accumulation of potentially toxic elements. The investigation encompassed the impact of various organic compost amendments, including leaf compost, cow dung manure, kitchen waste compost, municipal organic waste compost, and vermicompost. The study employed Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to evaluate soil nutrient levels and concentrations of Potentially Toxic Elements (PTEs) such as arsenic, chromium, cadmium, mercury, lead, nickel, and lithium. The fertilization and bioremediation potential of these compost amendments are quantified using an indexing method. Results indicated a substantial increase in overall nutrient levels (carbon, nitrogen, phosphorus, potassium, and sulfur) in soils treated with leaf compost and other organic composts. Fertility indices (FI) are notably higher in compost-amended soils (ranging from 2.667 to 3.938) compared to those amended with chemical fertilizers (ranging from 2.250 to 2.813) across all soil samples. Furthermore, the mean concentrations of PTEs were significantly lower in soils treated with leaf compost and other organic compost amendments compared to those treated with chemical fertilizers amendments. The assessment through the indexing method revealed a high clean index (CI) for leaf compost amendment (ranging from 3.407 to 3.58), whereas the chemical fertilizer amendment exhibits a relatively lower CI (ranging from 2.78 to 3.20). Consequently, leaf compost and other organic composts exhibit the potential to enhance sustainable productivity, promoting soil health and environmental safety by improving nutrient levels and remediating potentially toxic elements in the soil. 展开更多
关键词 Bio-Compost Soil Fertility Potentially Toxic Elements BIOREMEDIATION
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Short Communication: Enhancing the Drying Process of Microbial-Based Products with a Dehumidifier
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作者 Nor Hidayah Bohari Elya Masya Mohd Fishal +2 位作者 Ili Bazilah Abd Razak Muhammad Ashraf arif Mohd Nasir Cik Mohd Rizuan Zainal Abidin 《Advances in Microbiology》 CAS 2024年第6期333-339,共7页
The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, c... The development of microbial-based products requires certain criteria for them to be successfully commercialized. The product must meet the following desirable criteria: effectiveness, contamination free, stability, cost-effectiveness, and a prolonged shelf life. Controlling the drying process is crucial for ensuring the stability and durability of the product. The traditional approach, which involved mechanical and natural drying, led to decreased productivity and quality. The objective of this research endeavour was to achieve a dry process enhancement while preserving the microbial quality of Trichoderma asperellum (M103). The temperature and relative humidity during the drying period were monitored under two conditions: with and without a dehumidifier. The results demonstrate that the dehumidifier increases drying period efficiency by up to 63%. 展开更多
关键词 DEHUMIDIFIER DRYING Relative Humidity Microbial-Based Product
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A Review of Anomaly Detection Systems in Cloud Networks and Survey of Cloud Security Measures in Cloud Storage Applications 被引量:8
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作者 arif Sari 《Journal of Information Security》 2015年第2期142-154,共13页
Cloud computing has become one of the most projecting words in the IT world due to its design for providing computing service as a utility. The typical use of cloud computing as a resource has changed the scenery of c... Cloud computing has become one of the most projecting words in the IT world due to its design for providing computing service as a utility. The typical use of cloud computing as a resource has changed the scenery of computing. Due to the increased flexibility, better reliability, great scalability, and decreased costs have captivated businesses and individuals alike because of the pay-per-use form of the cloud environment. Cloud computing is a completely internet dependent technology where client data are stored and maintained in the data center of a cloud provider like Google, Amazon, Apple Inc., Microsoft etc. The Anomaly Detection System is one of the Intrusion Detection techniques. It’s an area in the cloud environment that is been developed in the detection of unusual activities in the cloud networks. Although, there are a variety of Intrusion Detection techniques available in the cloud environment, this review paper exposes and focuses on different IDS in cloud networks through different categorizations and conducts comparative study on the security measures of Dropbox, Google Drive and iCloud, to illuminate their strength and weakness in terms of security. 展开更多
关键词 ANOMALY DETECTION SYSTEMS CLOUD COMPUTING CLOUD Environment Intrustion DETECTION SYSTEMS CLOUD Security
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Greenhouse Gas Emissions from Agro-Ecosystems and Their Contribution to Environmental Change in the Indus Basin of Pakistan 被引量:8
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作者 M. Mohsin IQBAL M. arif GOHEER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第6期1043-1052,共10页
There is growing concern that increasing concentrations of greenhouse gases in the atmosphere have been responsible for global warming through their effect on radiation balance and temperature. The magnitude of emissi... There is growing concern that increasing concentrations of greenhouse gases in the atmosphere have been responsible for global warming through their effect on radiation balance and temperature. The magnitude of emissions and the relative importance of different sources vary widely, regionally and locally. The Indus Basin of Pakistan is the food basket of the country and agricultural activities are vulnerable to the effects of global warming due to accelerated emissions of GHGs. Many developments have taken place in the agricultural sector of Pakistan in recent decades in the background of the changing role of the government and the encouragement of the private sector for investment in new ventures. These interventions have considerable GHG emission potential. Unfortunately, no published information is currently available on GHG concentrations in the Indus Basin to assess their magnitude and emission trends. The present study is an attempt to estimate GHG (CO2, CH4 and N2O) emissions arising from different agro-ecosystems of Indus Basin. The GHGs were estimated mostly using the IPCC Guidelines and data from the published literature. The results showed that CH4 emissions were the highest (4.126 Tg yr^-1) followed by N20 (0.265 Tg yr^-1) and CO2 (52.6 Tg yr^-1). The sources of CH4 are enteric fermentation, rice cultivation and cultivation of other crops. N2O is formed by microbial denitrification of NO3 produced from applied fertilizer-N on cropped soils or by mineralization of native organic matter on fallow soils. CO2 is formed by the burning of plant residue and by soil respiration due to the decomposition of soil organic matter. 展开更多
关键词 greenhouse gases AGRICULTURE Indus Basin Pakistan
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Vitamin D Deficiency and Its Relationship with Child-Pugh Class in Patients with Chronic Liver Disease 被引量:8
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作者 Zubia Jamil Sharmin arif +2 位作者 Anum Khan Asghar Aurangzeb Durrani Nayyar Yaqoob 《Journal of Clinical and Translational Hepatology》 SCIE 2018年第2期135-140,共6页
Background and Aims:Skeletal manifestation in liver dis-eases represents the minimally scrutinized part of the disease spectrum.Vitamin D deficiency has a central role in developing hepatic osteodystrophy in patients ... Background and Aims:Skeletal manifestation in liver dis-eases represents the minimally scrutinized part of the disease spectrum.Vitamin D deficiency has a central role in developing hepatic osteodystrophy in patients with chronic liver disease.This study aimed to investigate vitamin D levels and their relationship with disease advancement in these patients.Methods:Vitamin D levels were checked in 125 chronic liver disease patients.The patients were classified in three stages according to Child-Pugh score:A,B and C.The relationship of vitamin D levels with Child-Pugh score and other variables in the study was assessed by the contingency coefficient.Correlation and logistic regression analyses were also carried out to find additional predictors of low vitamin D levels.Results:Among the patients,88%had either insufficient or deficient stores of vitamin D,while only 12%had sufficient vitamin D levels(p>0.05).Vitamin D levels were notably related to Child-Pugh class(contingency coefficient=0.5,p<0.05).On univariate and multinomial regression analyses,age,female sex,MELD and Child-Pugh class were predictors of low vitamin D levels.Age,model of end-stage liver disease score and Child-Pugh score were negatively correlated to vitamin D levels(p<0.05).Conclusions:Vitamin D deficiency is notably re-lated to age,female sex and model of end-stage liver disease score,in addition to Child-Pugh class of liver cirrhosis.Vita-min D levels should be routinely checked in patients with ad-vanced liver cirrhosis(Child-Pugh class B and C)and this deficiency must be addressed in a timely manner to improve general well-being of cirrhotic patients. 展开更多
关键词 Vitamin D deficiency Liver cirrhosis OSTEODYSTROPHY Liver disease Skeletal manifestations
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Handheld high-throughput plasmonic biosensor using computational on-chip imaging 被引量:8
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作者 arif E Cetin Ahmet F Coskun +4 位作者 Betty C Galarreta Min Huang David Herman Aydogan Ozcan Hatice Altug 《Light(Science & Applications)》 SCIE EI CAS 2014年第1期388-397,共10页
We demonstrate a handheld on-chip biosensing technology that employs plasmonic microarrays coupled with a lens-free computational imaging system towards multiplexed and high-throughput screening of biomolecular intera... We demonstrate a handheld on-chip biosensing technology that employs plasmonic microarrays coupled with a lens-free computational imaging system towards multiplexed and high-throughput screening of biomolecular interactions for point-of-care applications and resource-limited settings.This lightweight and field-portable biosensing device,weighing 60 g and 7.5 cm tall,utilizes a compact optoelectronic sensor array to record the diffraction patterns of plasmonic nanostructures under uniform illumination by a single-light emitting diode tuned to the plasmonic mode of the nanoapertures.Employing a sensitive plasmonic array design that is combined with lens-free computational imaging,we demonstrate label-free and quantitative detection of biomolecules with a protein layer thickness down to 3 nm.Integrating large-scale plasmonic microarrays,our on-chip imaging platform enables simultaneous detection of protein mono-and bilayers on the same platform over a wide range of biomolecule concentrations.In this handheld device,we also employ an iterative phase retrieval-based image reconstruction method,which offers the ability to digitally image a highly multiplexed array of sensors on the same plasmonic chip,making this approach especially suitable for high-throughput diagnostic applications in field settings. 展开更多
关键词 computational imaging high-throughput biodetection lens-free imaging on-chip sensing PLASMONICS point of care diagnostics telemedicine
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Online power quality disturbance detection by support vector machine in smart meter 被引量:8
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作者 Imtiaz PARVEZ Maryamossadat AGHILI +2 位作者 arif I.SARWAT Shahinur RAHMAN Fahmida ALAM 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2019年第5期1328-1339,共12页
Power quality assessment is an important performance measurement in smart grids.Utility companies are interested in power quality monitoring even in the low level distribution side such as smart meters.Addressing this... Power quality assessment is an important performance measurement in smart grids.Utility companies are interested in power quality monitoring even in the low level distribution side such as smart meters.Addressing this issue,in this study,we propose segregation of the power disturbance from regular values using one-class support vector machine(OCSVM).To precisely detect the power disturbances of a voltage wave,some practical wavelet filters are applied.Considering the unlimited types of waveform abnormalities,OCSVM is picked as a semisupervised machine learning algorithm which needs to be trained solely on a relatively large sample of normal data.This model is able to automatically detect the existence of any types of disturbances in real time,even unknown types which are not available in the training time.In the case of existence,the disturbances are further classified into different types such as sag,swell,transients and unbalanced.Being light weighted and fast,the proposed technique can be integrated into smart grid devices such as smart meter in order to perform a real-time disturbance monitoring.The continuous monitoring of power quality in smart meters will give helpful insight for quality power transmission and management. 展开更多
关键词 MACHINE learning ONE-CLASS support VECTOR MACHINE Power quality Disturbances SMART grid SMART METER
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MOF衍生的单原子催化剂中γN原子在ORR反应中的远程作用及其调制机制 被引量:1
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作者 邢浩然 Muhammad arif +3 位作者 何光裕 肖海 陈银娟 陈海群 《Science China Materials》 SCIE EI CAS CSCD 2023年第8期3200-3212,共13页
燃料电池的发展有助于促进“双碳”目标的早日实现,但其阴极氧还原反应(ORR)的多步质电耦合传输机制导致其动力学过程缓慢.目前,金属有机框架材料衍生的单原子催化剂(SACs)因具有较高的ORR催化活性而被认为是一种优势燃料电池阴极材料.... 燃料电池的发展有助于促进“双碳”目标的早日实现,但其阴极氧还原反应(ORR)的多步质电耦合传输机制导致其动力学过程缓慢.目前,金属有机框架材料衍生的单原子催化剂(SACs)因具有较高的ORR催化活性而被认为是一种优势燃料电池阴极材料.然而,由于SACs活性位点的外层结构难以精确表征,因此相关催化反应机制尚不明确.鉴于此,本研究着眼第三配位层γN原子对其邻近βC原子位点和活性金属中心的双重影响开展了深入研究.结果表明,不同位置和数量的γN掺杂会改变Fe–N_(4)/C–γN_(x)结构中被取代C位点的电子结构,从而影响邻近金属中心的βC原子电荷分布.同时,这些变化还将通过长程效应间接影响金属中心的电子分布及自旋,从而增强4e−反应路径的ORR性能.更重要的是,电负性增强的βC原子更容易吸附OH基团,因此使得γN掺杂的Fe–N_(4)/C–γN_(x)具备更加优异的碱性环境ORR理论性能.基于以上结果,我们还发现γN调制的βC辅助ORR路径具有比常规4e−反应路径更低的过电势.本研究针对决速步的波函数分析促进了从电子层次对该反应作用机制的理解,揭示了该类单原子催化剂中γN位点精确设计和表征的重要意义. 展开更多
关键词 单原子催化剂 反应路径 配位层 N掺杂 燃料电池 金属有机框架材料 电负性 阴极材料
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