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Inter-population variabilities in seed mass and germination of Panicum turgidum and Pennisetum divisum in the desert of Kuwait

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Journal of Arid Land 2020年第1期12卷 144-153页

作者： Arvind BHATT Narayana R BHAT Afaf AL-nasser María M CARÓN AndreaSANTO Kuwait Institute for Scientific Research Safat 24885Kuwait Laboratory of Botanical Research(LABIBO) Faculty of Natural SciencesNational University of Salta-CONICETSalta 4400Argentina Independent Researcher Selargius 09047Italy

Understanding variability in seed germination among populations is essential for planning an effective germplasm collection for restoration and conservation *** knowledge of germination and dormancy patterns among populations of desert grasses is crucial for determining the potential of the species and populations to be used for restoration and conservation as well as forage *** in seed germination of Panicum turgidum Forssk and Pennisetum divisum(Gmel.)*** the desert of Kuwait was evaluated in different populations in May *** of seed germination(25 seeds and 4 replicates)was conducted for each population at night/day temperatures of 15℃/20℃and 20℃/30℃under the following light condition:continuous darkness or 12 h/12 h light/*** showed that seed masses of both species strongly varied according to their seed provenances,and both species produced heavier seeds in population with a higher soil electrical *** germination percentage considerably varied between two species,and the variation in *** was greater(17%–49%)than that of ***(72%–93%).Germination percentage in *** was greater at high temperature(20℃/30℃)than at low temperature(15℃/20℃).However,temperature regimes had no effect on germination percentage of *** *** germination time of both species exhibited significant inter-population *** result is especially relevant to assure the selection of the best population of each species and the regeneration success of the *** this,inter-population variability also provides valuable information for enhancing our understanding of the mechanisms that regulate seed germination and how they might be related to seed provenance.

关键词： desert grass seed germination inter-population variability seed provenance seed dormancy

New flavonoids from bioactive extract of Algerian medicinal plant Launeae arborescens

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Asian Pacific Journal of Tropical Biomedicine 2014年第4期4卷 267-271页

作者： Khaled Sekkoum nasser Belboukhari Abdelkrim Cheriti Bioartive Molecule & Chiral separation Laboratory University of Bechar Phytochemistry & Organic Synthesis Laboratory University of Bechar

Objective:To investigate the butanol fraction of the water/acetone extract and isolate of the new flavonoids from Launeae ***:The compounds were isolated by liquid chromatographic methods and their structures were identified by using spectroscopic ***:The isolated compounds were identified as:7-0-[α-rhamnopyranosyl 4',5,6-Trihydroxy flavone 1,4',5'-Di-Methoxy 7-(5"-Me Hexan)1-oyl flavanone 2,3"-isopropyl pyrano[1":7,4":6]3',4',5',5-Tetrahydroxy flavanone 3,5,4',5'-Tri-Hydroxy 7-(3"-Me butan)-yl flavanone 4.5,7-Dihydroxy-2',4',5'-trimethoxy-isoflavanone 5,5,6,7,4'-tetrahydroxy flavonol 6,7-O-[α-rhamnopyranosyl-(1->6)-β-glucopyranosyl]-4',5,7-tri-hydroxy-flavanone 7,7-O-[α-rhamnopyranosyl-(1->6)-β-glucopyranosyl]3',5-Dihydroxy 4'-Methoxy flavanone ***:The presence of different types of bioactive flavonoids in Launeae arhoescens extract can explain the large ethnopharmacological uses and the potential activity of this medicinal plant.

关键词： Launeae arborescens Asteraceae Flavanone Isoflavanone Glycosid flavanone

Moisture and Temperature Response of Structural and Lithology based Thermophysical and Energy Saving Traits of Limestone using Experimental and Least-Square Fitting Methods

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Journal of Thermal Science 2021年第2期30卷 551-561页

作者： Farah Anjum Muhammad Yasin Naz Abdul Ghaffar Shazia Shukrullah nasser M AbdEl-Salam Khalid Aref Ibrahim Department of Physics University of AgricultureFaisalabad 38040Pakistan Arriyadh Community College King Saud UniversityArriyadh 11437Saudi Arabia College of Engineering Muzahimiyah BranchKing Saud UniversityRiyadh 11451Saudi Arabia Department of Physics College of Arts and SciencesUniversity of JhangJhang 35200Pakistan

Thermophysical analysis of the crustal rocks is important for heat transfer determination and insulation purposes to save energy in *** the presented work,thermophysical properties of four limestones were investigated in dry and moist state under ambient conditions by using a transient plane source method.A thermal constant analyzer was used to raise the sample temperature and to measure the thermal properties in the temperature range of 300 K to 433 *** conductivity and diffusivity were measured by developing a linear relationship between temperature response of TPS (transient plane source) sensor and dimensionless time function through least-square fitting *** experimental observations and predicted thermal conductivity of samples have shown that in-situ observations are important to determine the thermal properties *** effect of temperature on thermal properties of limestone was defined by considering the chemical composition of the samples and associated heat transfer *** thermal conductivity and diffusivity of limestone decreased while specific heat capacity increased with a rise in *** overall findings indicate that the spinoff of this research is useful in studying the reliance of thermophysical properties of rocks on their structures and lithology.

关键词： limestone thermophysical properties transient plane source(TPS) thermal conductivity

Application of a new SPA-SVM coupling method for QSPR study of electrophoretic mobilities of some organic and inorganic compounds

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Chinese Chemical Letters 2013年第10期24卷 904-908页

作者： nasser Goudarzi Mohammad Goodarzi M.Arab Chamjangali M.H.Fatemi Faculty of Chemistry Shahrood University of Technology Department of Chemistry Faculty of SciencesYong Researchers ClubAzad University Faculty of Chemistry Mazandaran University

In this work, two chemometrics methods are applied for the modeling and prediction of electrophoretic mobilities of some organic and inorganic compounds. The successive projection algorithm, feature selection （SPA） strategy, is used as the descriptor selection and model development method. Then, the support vector machine （SVM） and multiple linear regression （MLR） model are utilized to construct the non-linear and linear quantitative structure-property relationship models. The results obtained using the SVM model are compared with those obtained using MLR reveal that the SVM model is of much better predictive value than the MLR one. The root-mean-square errors for the training set and the test set for the SVM model were 0.1911 and 0.2569, respectively, while by the MLR model, they were 0.4908 and 0.6494, respectively. The results show that the SVM model drastically enhances the ability of prediction in QSPR studies and is superior to the MLR model.

关键词： Quantitative structure-mobility relationship Support vector machine Electrophoretic mobility Successive projection algorithm Multiple linear regression

Long-term complications of the transmeatal approach (Open Transcanal) in cochlear implants: A follow-up study

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Journal of Otology 2023年第1期18卷 33-37页

作者： Hesham Saleh Almofada nasser KAlmutairi Michael Steven Timms King Faisal Specialist Hospital and Research Center RiyadhSaudi Arabia Al Faisal University College of MedicineSaudi Arabia Saudi German Hospital DubaiUnited Arab Emirates

Objective: Multiple alternative approaches of cochlear implant surgery have been described, such as the suprameatal approach, transcanal approach, transmeatal approach and middle cranial fossa ***(open trnascanal) approach has not been adapted since first described in the clinical *** aimed to assess the long-term complications of the transmeatal approach in a series of 131 patients at our center between 2004 and ***: This study was a retrospective case series of all patients who underwent cochlear implants with the transmeatal(open transcanal) approach from May 2004 to December 2008 at King Faisal Specialist and Research Hospital(Riyadh, Saudi Arabia), which were conducted by the same ***: Complications were observed often with various combinations-recurrent otitis externa, posterior tympanic membrane perforation, electrode extrusion, cholesteatoma, and chronic mastoiditis. The overall long-term complication rate was 16%(21/131). The gap between the implantation and the diagnosis of a complication ranged from <1 year to 11 years. Major complications were as follows:cholesteatoma in 5(3.8%) patients, extrusion of the electrode in 5(3.8%) patients, and tympanic membrane perforation or deep retractions in 5(3.8%) patients. Minor complications were as follows: recurrent mastoiditis with/without concomitant temporary facial nerve palsy in 4(3%) patients, recurrent otitis externa infections in 7(5%) patients, and weakness of the posterior canal wall in 1 ***: The transmeatal approach posed an high rate of complications on long-term follow-up such as cholestetoma formation, extrusion of electrode or perielectrode reaction formation to tympanic membrane and external auditory canal.

关键词： Cochlear implant Transmeatal approach Open transcanal approach Surgical complication

Techniques for Enhancement of Noisy Speech in Adverse Environments

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Techniques for Enhancement of Noisy Speech in Adverse Enviro...

作者： SAMATIN NJIKAM ABOUBAKAR nasser 湖南大学

学位级别：硕士

近年来,针对受加性噪声污染的语音信号进行语音增强的研究备受关注。在这些语音增强系统的设计过程中主要有两个部分：干净语音谱估计和噪声谱估计。本论文着重解决这两个问题。本论文的第一个贡献是提出了一种改进的语音增强技术。该... 详细信息

近年来,针对受加性噪声污染的语音信号进行语音增强的研究备受关注。在这些语音增强系统的设计过程中主要有两个部分：干净语音谱估计和噪声谱估计。本论文着重解决这两个问题。本论文的第一个贡献是提出了一种改进的语音增强技术。该技术基于语音信号对数幅度谱的最小均方误差估计(MMSE-LSA)和一种有效的先验无语音概率(SAP)估计。先验无语音概率是本文改进MMSE-LSA的必要组成部分。不少基于LSA估计的语音增强方法要么直接采用一个较小的固定值作为先验SAP,要么采用一个较小的固定值作为先验SAP的参数。由于先验无语音概率的计算受到纯噪声段的影响,因此使用一个固定值来计算先验SAP的方法就显得不适合、不优良。更好的方法是使用动态的参数来计算先验SAP,这样就可以在每一帧中对其进行更新。这篇文章中,我们提出了两个和先验SAP计算有关的动态因子：一个平滑更新因子以及一个与第k个谱成分相关的因子。平滑更新因子取决于频带语音信号存在与否的判决,具体的计算方式是对之前的先验SAP递归取平均值。而与第k个谱成分相关的因子则依赖于先验信噪比(SNR)。判断一个频率带中是否存在语音信号是通过计算和比较带噪语音谱的条件概率来实现的。我们采用了两种客观评价方法和语谱图来对所提算法进行性能评估。实验结果表明,不管是语音质量、背景噪声的消除还是语音失真的数量,该算法都有显著的优越性。本论文的第二个贡献是为嘈杂环境下的噪声估计提出了一种替代方法。算法是基于一个追踪最小噪声语音的最优方法。本算法通过连续的求解带噪语音的过去频谱值均值和一个在语音存在段用来控制噪声谱估计更新的平滑更新因子来实现的。动态平滑更新因子是基于频率带是否存在语音信号的判决来计算得到的。区别语音存在和不存在则是通过计算出带噪语音能量谱和相应局部最小值的差值来判断的。与其它方法不同的是,我们的算法不需要明确使用语音存在概率来完成计算。评估所提出的算法用到了NOIZEUS数据库,实验结果表明,当把本文所提噪声估计算法整合到语音增强中,能够获得更好的语音质量和明显的噪声消除,同时也最小化了语音失真数量和音乐噪声。

关键词： MMSE-LSA估算语音增强无语音概率噪声估计最小统计

Indolent lung opacity: Ten years follow-up of pulmonary inflammatory pseudo-tumor

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World Journal of Clinical Cases 2017年第2期5卷 61-66页

作者： Jad A Degheili Nadim A Kanj Salwa A Koubaissi Mouhamad J nasser Division of General Surgery Department of Surgery American University of Beirut-Medical Center Division of Pulmonary Critical Care and Sleep Medicine Department of Internal Medicine American University of Beirut-Medical Center Department of Internal Medicine American University of Beirut-Medical Center

Inflammatory pseudotumor(IPT) has always been considered a diagnostic challenge. Its rarity and resemblance to other more common pathological entities imposes that neither clinical nor radiological characteristics can lead to a definitive diagnosis. The surgical excision of the lesion is the ultimate approach for accurate diagnosis and cure. Moreover the true nature of IPT, its origin as a neoplastic entity or an overreactive inflammatory reaction to an unknown trigger, has been a long debated matter. Surgery remains the treatment of choice. IPT is mostly an indolent disease with minimal morbidity and mortality. Local invasion and metastasis predict a poor prognosis. We hereby present a unique case of pulmonary IPT that was surgically excised, but recurred contralaterally, shortly thereafter. Despite no medical or surgical treatment for ten years, the lesion has remained stable in size, with neither symptoms nor extra-pulmonary manifestations.

关键词： Inflammatory pseudotumor Anaplastic lymphoma kinase Inflammatory myofibroblastic tumor Plasma cells granuloma IgG4-related sclerosing disease

Determinants of overweight and obesity and preventive strategies in Pacific countries: a systematic review

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Global Health Journal 2022年第3期6卷 122-128页

作者： Tanebu Julia Tong Masoud Mohammadnezhad nasser Salem Alqahtani Ministry of Health and Medical Services Tarawa 487Kiribati Faculty of Health Studies School of Nursing and Healthcare LeadershipUniversity of BradfordBradfordWest Yorkshire BD71DPUnited Kingdom Department of Clinical Nutrition Northern Border UniversityArar 1321Saudi Arabia

Objective:This study aimed to explore more on contributing factors and prevention of overweight and obesity among Pacific ***:Using Cochrane library guideline,four electronic databases,PubMed,Embase,Scopus and CINAHL,were systematically searched from 2010 to *** strategy included key concepts,free text terms,and database-controlled vocabulary terms to identify articles on determinants and preventative strategies of overweight and obesity in the Pacific countries.A data extraction sheet was developed to extract relevant information required for analysis and theme development for this ***:A total of 22 articles were summarized and *** of overweight and obesity identified two themes:environmental related factors 13.6%(3/22)and sociocultural related factors 27.3%(6/22).The preventative strategies of overweight and obesity was categorized into behavioural change 22.7%(5/22),school-related 18.2%(4/22),and policies 50%(11/22).The quality assessment of articles showed“Good”68.2%(15/22),and“Fair”31.8%(7/22).Conclusion:This study highlighted two contributing,non-medication factors affecting overweight and obesity are both environmental and socio-cultural *** and obesity preventative strategies identified in the Pacific context considered behavioural change,knowledge enhancement,and policy *** research should aim at exploring the current preventative strategies in-depth,to appreciate the most feasible and recommended preventative approach within the Pacific society.

关键词： Determinants Preventative strategies Overweight Obesity Pacific Systematic review

Oral and perioral herpes simplex virus infection type I in a fivemonth- old infant: A case report

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World Journal of Clinical Cases 2021年第3期9卷 685-689页

作者： Ashwag Yagoub Aloyouny Hamad nasser Albagieh Rasha Hamed Al-Serwi Basic Dental Science Department College of DentistryPrincess Nourah bint Abdulrahman UniversityRiyadh 11671RiyadhSaudi Arabia Oral Medicine and Diagnostic Science Department College of DentistryKing Saud UniversityRiyadh 12372RiyadhSaudi Arabia

BACKGROUND Herpes simplex virus(HSV)is a highly infectious pathogen that is easily transmitted via the bodily fluids of an infected *** virus usually affects individuals older than six months of age,and rarely causes lesions or symptoms in younger *** SUMMARY We present the case of a five-month-old healthy girl who presented with painful herpetic gingivostomatitis and perioral *** discuss the pathophysiology of primary HSV infection and the effect of maternal antibodies on the infant’s immune *** addition,we explain the diagnosis,management,and prognosis of HSV infection in young *** This case highlights the importance of early diagnosis and management of HSV infections to decrease the risk of developing severe complications and death.

关键词： Herpetic gingivostomatitis Oral lesions Herpes simplex virus Perioral lesions Infants Case report Herpes simplex virus type 1