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Wireless Engineering and Technology 2013年第2期4卷 77-86页

作者： reham A. El-Mayet hesham M. El-Badawy Salwa h. Elramly Electronic and Communication Department Ain Shams University Cairo Egypt National Telecommunication Institute Cairo Egypt

To provide quality-of service (QoS) guarantees for heterogeneous applications, most recent wireless communications technologies and standards combine the error-correcting capability of hybrid automatic repeat request (hARQ) schemes at the data link layer (DLL) with the adaptation ability of the adaptive modulation and coding (AMC) modes at the physical layer (PhY) layer. This paper aims to investigate the aggregated system capacity as well as the breakdown of this capacity for different ACM modes in each hARQ scheme. This investigation was done by using maximum weighted capacity (MWC) resource allocation at the PhY layer in conjunction with a novel packet error rate (PER)-based scheduling at the medium access control (MAC) layer. As a result, the dominant AMC mode corresponding to channel SNR was available.

关键词： AMC Cross-Layer Design hARQ Nakagami-m Fading Channel QoS

Safest Route Detection via Danger Index Calculation and K-Means Clustering

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Computers, Materials & Continua 2021年第11期69卷 2761-2777页

作者： Isha Puthige Kartikay Bansal Chahat Bindra Mahekk Kapur Dilbag Singh Vipul Kumar Mishra Apeksha Aggarwal Jinhee Lee Byeong-Gwon Kang Yunyoung Nam reham R.Mostafa School of Engineering and Applied Sciences Bennett UniversityGreater NoidaIndia Department of ICT Convergence Soonchunhyang UniversityAsanKorea Department of Information Systems Faculty of Computers and Information SciencesMansoura UniversityMansouraEgypt

The study aims to formulate a solution for identifying the safest route between any two inputted Geographical *** the New York City dataset,which provides us with location tagged crime statistics;we are implementing different clustering algorithms and analysed the results comparatively to discover the best-suited *** results unveil the fact that the K-Means algorithm best suits for our needs and delivered the best ***,a comparative analysis has been performed among various clustering techniques to obtain best *** compared all the achieved results and using the conclusions we have developed a user-friendly application to provide safe route to *** successful implementation would hopefully aid us to curb the ever-increasing crime rates;as it aims to provide the user with a beforehand knowledge of the route they are about to take.A warning that the path is marked high on danger index would convey the basic hint for the user to decide which path to ***,addressing a social problem which needs to be eradicated from our modern era.

关键词： Agglomerative clustering crime rate danger index DBSCAN

那不勒斯热袍菌纤维素酶的表达、酶学性质分析及应用

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那不勒斯热袍菌纤维素酶的表达、酶学性质分析及应用

作者： reham mohammed mohammed Ebaid 江苏大学

学位级别：硕士

在生物质的各种工业应用中,生物燃料的生产越来越受到重视。许多因素影响生物质能转化为生物燃料,如生物质成分、水分含量和最终所需的能源产品。在各种转化方法中,酶解法将生物质转化为可发酵糖具有高产、低能耗、高选择性和生态友好... 详细信息

在生物质的各种工业应用中,生物燃料的生产越来越受到重视。许多因素影响生物质能转化为生物燃料,如生物质成分、水分含量和最终所需的能源产品。在各种转化方法中,酶解法将生物质转化为可发酵糖具有高产、低能耗、高选择性和生态友好等优点。在这方面,超嗜热酶在极端温度下的稳定性使它们具有独特的生物质转化潜力。近年来,为了提高耐热酶的生物产量和稳定性,人们进行了大量的试验。除了优化生长条件和使用化学方法外,还开发了许多新的遗传表达系统。本研究利用phsh-T载体,从那不勒斯热热袍菌中分离到嗜热纤维素酶(hyperthermophilic cellulase,hTC)基因并在大肠杆菌中表达。确定了该酶95℃为最佳温度。最佳ph值在6.0-6.5之间,在碱性环境中比在酸性环境中更稳定。此外,该酶在95℃孵育时表现出较高的热稳定性,孵育5小时后活性最高。hTC的这些优越性质有力地支持了酶在纤维素生物质水解中用于生物燃料生产或其他工业中的应用。木质纤维素生物质中木质素的存在以及纤维素和半纤维素的解聚限制了酶法转化生物质的效率。微藻和蓝藻由于其细胞壁缺乏木质素,因此被认为是生物燃料(第三代)的潜在原料。在不同种类的蓝藻中,螺旋藻(Spirulina platensis)被认为是最具应用潜力的原料,包括生物燃料的生产。因此,本论文研究了静态磁场(SMF)对螺旋藻生物量生产、碳水化合物积累的影响及其对镉离子(Cd)去除率的影响。此外,还研究了hTC对SMF和高浓度Cd条件下生长的螺旋藻水解的影响。施用6 h·天的SMF,螺旋藻生物量的生产强度最高为0.198 g·L·天。然而,Cd浓度为10 mg·L和15mg·L时,螺旋藻生物量分别比对照降低了8.8%和12.5%。与对照相比,SMF组合显著提高了30.1%的生物量。另一方面,初始Cd浓度的增加导致Cd去除率显著降低,分别为10 mg·L和15 mg·L时的79.7%和61.5%。有趣的是,在初始Cd浓度为10mg·L和15 mg·L的培养基中,使用SMF 6 h·天可以提高Cd的去除率,在20天后,这两种培养基的去除率分别提高了91.4%和82.3%,分别比未经SMF处理的培养基提高了6.3%和25.3%。此外,SMF的应用导致碳水化合物的积累,并同时促进生长,这导致碳水化合物的产量在未经处理的培养基上显著增加。纤维分析结果为7.3%的dw纤维素和13.2%的dw半纤维素,未检测出木质素。以螺旋藻为原料,采用酶法水解螺旋藻,并与传统的酸预处理方法进行了比较。在最高应用浓度(10%)的应用条件下,酸预处理显示,最大还原糖量为1.37μg·mL。然而,使用10μL hTC酶,孵化基质30分钟,应用结果显示达到它的最大还原糖量为1.39μg·mL。另外利用红外光谱来确定纤维水解的程度,分析了结构性变化。在生物质原料中,3422 cm的条带对应O-h拉伸,表明存在纤维素和/或酸。酸预处理使该峰增大是由于样品被酸饱和,而hTC处理使该峰显著降低,证实了纤维素结构在消化纤维中由于破坏了纤维素中的氢键而变得疏松。2945 cm处的吸收带与C-h拉伸有关,证实了纤维素的甲基和亚甲基基团在酸和酶预处理后均被部分除去。此外,酶处理样品在1654 cm(C=O拉伸)处峰值强度的降低可能是由于酶水解纤维素导致半纤维素的部分降解。在95℃培养12小时后,hTC在结晶纤维素上的相对活性最大。然而,当孵育时间增加到48小时后,相对活性变化不明显。因此,该酶与纤维素(12h)相比与纤维素(5h)相比,需要更长的时间才能达到其最大活性。综上所述,目前的结果证实了hTC对纤维素及其结晶形态的显著作用,在未来将有广泛的工业应用。

关键词：纤维素酶超耐热酶热稳定性那不勒斯热袍菌生物质螺旋藻

Role of Nerve Growth Factor (NGF) and Its Receptor Tyrosine Kinase A (TrK A) in Egyptian Cirrhotic Patients with Pruritus

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Open Journal of Gastroenterology 2018年第9期8卷 317-326页

作者： Amr Zaghloul hanan Assaf reham Ezz mohamed Malak Mahmoud Rezk Ashraf Askar Essam El-dinNada Sohag University hospital Sohag Egypt

Background: Pruritus is a distressing symptom of cholestatic, inflammatory, and malignant liver diseases. It is a common symptom in many biliary and cholestatic disorders such as primary biliary cirrhosis (PBC). Several mechanisms are generally accepted as possible explanations to the underlying basis of itch. however, the exact pathophysiology of pruritus in liver diseases remains unclear. The cutaneous and central neurobiology of pruritus is complex and underlies a regulation of variable mechanisms. At present, not all mechanisms including neuromediators and receptors are known. Objective: Our objective is to evaluate whether the expression pattern of NGF and its receptor TrK A has a role in pruritus in a group of Egyptian cirrhotic patients. Patients and Methods: Forty Patients with liver cirrhosis were enrolled in the study depending on clinical evidence of stigmata of chronic liver disease (e.g. jaundice, ascites, palmar erythema, spider naevi, etc.) and ultrasonographic features of liver cirrhosis (e.g. coarse echo texture, shrunken liver, etc.). Patients were divided into two groups. Group (1): included 20 patients cirrhotic patients without pruritus. Group (2): included 20 patients cirrhotic patients with pruritus. A group of age and sex matched healthy twenty volunteers as a control. Results: After evaluation of histopathological using hematoxylin and eosin stained sections (h&E) was done. There was positive correlation between NGF protein expression and severity of pruritus in cirrhotic patients with pruritus (r = 0.876, p value ≤ 0.001). Also there was positive correlation between TrK A protein expression and severity of pruritus in cirrhotic patients with pruritus (r = 0.44, p value ≤ 0.05). Conclusions: We report, for the first time, role of these proteins (NGF/TrK A) in the mechanism of pruritus in cirrhotic patients and may provide a potential target for new treatment of pruritus in cirrhotic.

关键词： Liver Cirrhosis Itching Nerve Growth Factor (NGF) and Its Receptor Tyrosine Kinase A (TrK A)

A randomized open-label trial of on-demand rabeprazole vs ranitidine for patients with non-erosive reflux disease

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World Journal of Gastroenterology 2012年第19期18卷 2390-2395页

作者： Abdallah A Kobeissy Jana G hashash Faek R Jamali Assaad M Skoury reham haddad Sarah El-Samad Rami Ladki Rola Aswad Assaad M Soweid Division of Gastroenterology Department of Internal MedicineAmerican University of Beirut Medical CenterHamra 1103 2090BeirutLebanon Department of Surgery American University of Beirut Medical CenterHamra 1103 2090BeirutLebanon Department of Pharmacy Practice School of PharmacyLebanese American UniversityPO Box 36ByblosLebanon

AIM： To compare the efficacy of the proton-pump inhibitor, rabeprazole, with that of the h2-receptor antagonist, ranitidine, as on-demand therapy for relieving symptoms associated with non-erosive reflux disease （NEed）.METhODS： This is a single center, prospective, randomized, open-label trial of on-demand therapy with rabeprazole （group A） vs ranitidine （group B） for 4 wk. Eighty-three patients who presented to the American University of Beirut Medical Center with persistent gas- troesophageal reflux disease （GERD） symptoms and a normal upper gastrointestinal endoscopy were eligible for the study. Patients in group A （n = 44） were al-lowed a maximum rabeprazole dose of 20 mg twice daily, while those in group B （n = 39） were allowed a maximum ranitidine dose of 300 mg twice daily. Ef- ficacy was assessed by patient evaluation of global symptom relief, scores of the SF-36 quality of life （QoL） questionnaires, total number of pills used, and number of medication-free days.RESULTS： Among the 83 patients who were enrolled in the study, 76 patients （40 in the rabeprazole group and 36 in the ranitidine group） completed the 4-wk trial. Baseline characteristics were comparable between both groups. After 4 wk, there was no significant difference in the subjective global symptom relief between the rabeprazole and the ranitidine groups （71.4% vs 65.4%, respectively; P = 0.9）. There were no statistically significant differences between mean cumulative scores of the SF-36 QoL questionnaire for the two study groups （rabeprazole 22.40±27.53 vs ranitidine 17.28 ± 37.06; P = 0.582）. There was no significant difference in the mean number of pills used （rabeprazole 35.70±29.75 vs ranitidine 32.86±26.98; P = 0.66）. There was also no statistically significant difference in the mean number of medication-free days between both groups.CONCLUSION： Rabeprazole has a comparable efficacy compared to ranitidine when given on-demand for the treatment of NERD. Both medications were associat

关键词： Proton-pump inhibitors h2-receptor antag-onists Non-erosive reflux disease Gastroesophagealreflux disease Quality of life

Classification of marine Ascomycota,Basidiomycota,Blastocladiomycota and Chytridiomycota

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Fungal Diversity 2015年第4期73卷 1-72页

作者： E.B.Gareth Jones Satinee Suetrong Jariya Sakayaroj Ali h.Bahkali mohamed A.Abdel-Wahab Teun Boekhout Ka-Lai Pang Department of Botany and Microbiology College of ScienceKing Saud UniversityP.O.Box:2455Riyadh 1145Saudi Arabia Fungal Biodiversity Laboratory BIOTECNational Science and Technology Development Agency(NSTDA)113 Thailand Science ParkThanon PhahonyothinTombon Khlong NuengAmphoe Khlong LuangPathum Thani 12120Thailand Department of Botany Faculty of ScienceSohag UniversitySohagEgypt CBS Fungal Biodiversity Centre(KNAW) Uppsalalaan 83584CT UtrechtThe Netherlands Institute of Marine Biology and Center of Excellence for the Oceans Taiwan Ocean University2 Pei-Ning RoadKeelung 20224TaiwanRepublic of China

This paper lists the accepted names and classification of marine fungi,updating the scheme presented in *** classification includes 1,112 species(in 472 genera):Ascomycota 805(in 352 genera),Basidiomycota 21 species(in 17 genera),Chytridiomycota and related phyla 26 species(in 13 genera),Zygomycota three(in two genera),Blastocladiomycota one species(one genus),asexual morphs of filamentous fungi 43(in 26 genera);and marine yeasts:Ascomycota 138 species(in 35 genera),Basidiomycota 75 species(in 26 genera).These fungi belong to 129 families and 65 *** halosphaeriaceae remains the largest family of marine fungi with 141 species in 59 genera,while the most specious genera are Aspergillus(47 species),Penicillium(39 species)and the yeast genus Candida(64 species).The review includes details of recent higher order nomenclature changes,and accounts of new families,genera and species described over the past 5 years.

关键词： Fungal classification Marine fungi Molecular phylogeny New taxa Praelongicaulis gen nov Tirisporellales Torpedosporales ordo nov