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Food and Nutrition Sciences 2024年第9期15卷 905-920页

作者： Paulo Cumbane Angellique Niyragira Anésia Felicidade Machava Borges Chambal Faculty of Engineering Department of Chemical Engineering Universidade Eduardo Mondlane Maputo Mozambique Instituto Superior de Cincias e Tecnologia de Moambique (ISCTEM) Maputo Mozambique

This study investigated the antioxidant activity and alpha-amylase inhibitory potential of the methanolic extract from Vangueria infausta fruits with the aim of exploring its therapeutic and nutritional applications. Bioactive compounds such as total phenolics (TPC) and total alkaloids (TAC) were analyzed. Antioxidant activity was assessed using the DPPH, ABTS, FRAP, Ferrozine, Phosphomolybdate, and Folin-Ciocalteu methods, while alpha-amylase inhibitory activity was determined using the 3,5-Dinitrosalicylic Acid (DNSA) and 2-chloro-p-nitrophenyl-α-D-maltotrioside (CNPG3) methods. The results revealed significant variations in antioxidant activity across the methods used, with IC50 values ranging from 318.42 to 1255.56 µg/mL. Alpha-amylase inhibition was also significant, with IC50 values ranging from 140.85 to 121.06 µg/mL. The TPC was found to be 95.6 mg of gallic acid equivalent per 100 g of dry powder, and the TAC was 0.188 mg of atropine equivalent per 100 g of dry powder. These findings suggest that Vangueria infausta possesses promising antioxidant and alpha-amylase inhibitory potential, indicating its potential application in antioxidant therapies and in the management of carbohydrate digestion.

关键词： Vangueria infausta Antioxidant Activity Alpha-Amylase Inhibition TPC TAC

游戏教学法在汉语初级口语课中的应用研究 ——以马来西亚诗巫技职学院为例

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游戏教学法在汉语初级口语课中的应用研究 ——以马来西亚诗巫技...

作者： CHRISTINE sia CHOU ENG（谢周訇）河北大学

学位级别：硕士

人际关系是否融洽,口语交际能力至关重要。如何提升学生的口语表达能力,是汉语作为第二语言教学中要思考的重要问题之一。游戏教学法,寓教于乐,将其应用于汉语口语课堂,可以激发学生学习的兴趣。论文将理论与实践相结合,以作者在马来西... 详细信息

人际关系是否融洽,口语交际能力至关重要。如何提升学生的口语表达能力,是汉语作为第二语言教学中要思考的重要问题之一。游戏教学法,寓教于乐,将其应用于汉语口语课堂,可以激发学生学习的兴趣。论文将理论与实践相结合,以作者在马来西亚诗巫技职学院所执教的2022级四年级烹饪班为研究对象,运用游戏教学法设计了具体的教学方案,并以《汉语》I中第四课的内容为基础进行了教学实践。通过调查问卷和口语测试的方法,对游戏教学法在教学中的效果进行了评估。研究结果表明,游戏教学法在激发学习兴趣、促进同学间关系融洽、丰富教学形式等方面具有显著的帮助效果。这一方法不仅增强了课堂互动,还为汉语教学提供了新思路,对推广汉语作为第二语言教学具有重要价值。但是经过教学实践也发现其应用过程中容易出现游戏目标模糊、时长不易掌控、及游戏类型选择不当等各种问题。针对上述问题,从游戏设计、游戏实施和口语测试三个阶段提出一些建议。教师必须要有精准的时间规划,以确保教学内容能在规定的时间内顺利完成,这包括提前制定游戏规则,并在课堂上清晰地解释,从而节省时间并确保学生能够全面理解游戏的要求和规则。除此之外,教师在实行游戏教学法时应考虑教学目标和内容,这是教师设计游戏时应该特别注意的关键点。这意味着教师需要在设计游戏时明确教学目标,并确保游戏的每个环节都与这些目标紧密相关,使学生在游戏过程中能够获得足够的语言输入和实践机会,并最终达到教学目标。最后,希望此研究可以为职业院校的汉语口语教学提供参考。

关键词：游戏教学法马来西亚技职学院初级汉语口语课

Highly efficient fiber to Si waveguide free-form coupler for foundry-scale silicon photonics

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Photonics Research 2024年第5期12卷 1055-1066页

作者： LUIGI RANNO JIA Xu BRIAN sia COSMIN POPESCU DREW WENINGER SAMUEL SERNA SHAOLIANG YU LIONEL C.KIMERLING ANURADHA AGARWAL TIAN GU JUEJUN HU Department of Materials Science&Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA Centre for Micro-&Nano-Electronics(CMNE) Nanyang Technological UniversitySingapore 639798Singapore Department of Physics Photonics and Optical EngineeringBridgewater State UniversityBridgewaterMassachusetts 02324USA Zhejiang Laboratory Hangzhou 311100China Materials Research Laboratory Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

As silicon photonics transitions from research to commercial deployment,packaging solutions that efficiently couple light into highly compact and functional sub-micrometer silicon waveguides are imperative but remain *** 220 nm silicon-on-insulator(SOI)platform,poised to enable large-scale integration,is the most widely adopted by foundries,resulting in established fabrication processes and extensive photonic component *** development of a highly efficient,scalable,and broadband coupling scheme for this platform is therefore of paramount *** two-photon polymerization(TPP)and a deterministic free-form micro-optics design methodology based on the Fermat’s principle,this work demonstrates an ultraefficient and broadband 3-D coupler interface between standard SMF-28 single-mode fibers and silicon waveguides on the 220 nm SOI *** coupler achieves a low coupling loss of 0.8 dB for the fundamental TE mode,along with 1 dB bandwidth exceeding 180 *** broadband operation enables diverse bandwidthdriven applications ranging from communications to ***,the 3-D free-form coupler also enables large tolerance to fiber misalignments and manufacturing variability,thereby relaxing packaging requirements toward cost reduction capitalizing on standard electronic packaging process flows.

关键词： fiber waveguide enable

1967~2033 nm波段硅基可调谐外腔半导体激光器设计与仿真

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中国激光 2024年第6期51卷 74-83页

作者：万浩然杨禹霖乔忠良李翔 Jia Xu Brian sia 余文军翁登群李再金李林陈浩赵志斌薄报学高欣曲轶刘重阳汪宏张宇牛智川海南师范大学物理与电子工程学院海南省激光技术与光电子功能材料重点实验室半导体激光海南省国际联合研究中心海南海口571158 新加坡南洋理工大学电气与电子工程学院新加坡639798 新加坡南洋理工大学淡马锡实验室新加坡637553 中国科学院半导体研究所半导体超晶格国家重点实验室北京100083 长春理工大学高功率半导体激光器国家重点实验室吉林长春130022

2μm波长附近可调谐半导体激光器在分子光谱学和光通信领域中有广阔的应用前景。基于绝缘体上硅(SOI)平台,对2μm波长附近可调谐半导体激光器的外腔部分进行了设计优化。分析了不同尺寸光波导的模式损耗特性、单个微环谐振腔受总线波导... 详细信息

2μm波长附近可调谐半导体激光器在分子光谱学和光通信领域中有广阔的应用前景。基于绝缘体上硅(SOI)平台,对2μm波长附近可调谐半导体激光器的外腔部分进行了设计优化。分析了不同尺寸光波导的模式损耗特性、单个微环谐振腔受总线波导耦合间距的作用以及总线波导光反馈终端对外腔半导体激光器性能的影响。并提出了一种具有高工艺兼容度的多模环形光波导光反馈结构。所设计的可调谐半导体激光器硅基外腔可通过环形波导上的镍铬合金微加热器进行0.1 nm/K的高精度调谐,对单个微加热器施加3.2 V电压时,调谐范围可达66 nm(1967~2033 nm)。

关键词：硅光集成可调谐外腔半导体激光器环形谐振腔光波导终端

Refraction characteristics of phononic crystals

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Acta Mechanica Sinica 2015年第4期31卷 481-493页

作者： sia Nemat-Nasser Department of Mechanical and Aerospace Engineering University of California

Some of the most interesting refraction prop- erties of phononic crystals are revealed by examining the anti-plane shear waves in doubly periodic elastic composites with unit cells containing rectangular and/or elliptical multi- inclusions. The corresponding band structure, group velocity, and energy-flux vector are calculated using a powerful mixed variational method that accurately and efficiently yields all the field quantities over multiple frequency pass-bands. The background matrix and the inclusions can be anisotropic, each having distinct elastic moduli and mass densities. Equifrequency contours and energy-flux vectors are read- ily calculated as functions of the wave-vector components. By superimposing the energy-flux vectors on equifrequency contours in the plane of the wave-vector components, and supplementing this with a three-dimensional graph of the corresponding frequency surface, a wealth of information is extracted essentially at a glance. This way it is shown that a composite with even a simple square unit cell con- taining a central circular inclusion can display negative or positive energy and phase velocity refractions, or simply performs a harmonic vibration （standing wave）, depending on the frequency and the wave-vector. Moreover, that the same composite when interfaced with a suitable homoge- neous solid can display：（1） negative refraction with negative phase velocity refraction; （2） negative refraction with pos- itive phase velocity refraction; （3） positive refraction with negative phase velocity refraction; （4） positive refraction with positive phase velocity refraction; or even （5） completereflection with no energy transmission, depending on the fre- quency, and direction and the wavelength of the plane-wave that is incident from the homogeneous solid to the interface. For elliptical and rectangular inclusion geometries, analyti- cal expressions are given for the key calculation quantities. Expressions for displacement, velocity, linear m

关键词： Doubly periodic composites - Phononiccrystals Band structure Group and energy-flux vectors

Genetic and Agronomic Parameter Estimates of Growth, Yield and Related Traits of Maize (Zea mays L.) under Different Rates of Nitrogen Fertilization

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American Journal of Plant Sciences 2024年第4期15卷 274-291页

作者： Prince Emmanuel Norman Lansana Kamara Aloysius Beah Kelvin Sahr Gborie Francess sia Saquee Sheku Alfred Kanu Fayia Augustine Kassoh Yvonne Sylvia Gloria Ethel Norman Abdul Salaam Kargbo Sierra Leone Agricultural Research Institute (SLARI) Freetown Sierra Leone School of Agriculture Njala University Njala Campus Njala Sierra Leone School of Natural Resources Management Njala University Njala Campus Njala Sierra Leone Department of Agro Biotechnology Institute of Agriculture RUDN University Moscow Russia Faculty of Development Agriculture & Natural Resources Management Eastern Technical University of Sierra Leone Kenema Sierra Leone

This study evaluated the genetic and agronomic parameter estimates of maize under different nitrogen rates. The trial was established at the Njala Agricultural Research Centre experimental site during 2021 and 2022 in a split block design with three maize varieties (IWCD2, 2009EVDT, and DMR-ESR-Yellow) and seven nitrogen (0, 30, 60, 90, 120, 150 and 180 kg∙N∙ha−1) rates. Findings showed that cob diameter and anthesis silking time (ASI) had intermediate heritability, ASI had high genetic advance, ASI and grain yield had high genotypic coefficient of variation (GCV), while traits with high phenotypic coefficient of variation (PCV) were plant height, ASI, grain yield, number of kernel per cob, number of kernel rows, ear length, and ear height. The PCV values were higher than GCV, indicating the influence of the environment in the studied traits. Nitrogen rates and variety significantly (p −1 plots exhibiting the lowest and highest grain yields of 1238 kg∙ha−1 and 2098 kg∙ha−1, respectively. Variety and nitrogen effects on partial factor productivity (PFPN), agronomic efficiency (AEN), net returns (NR), value cost ratio (VCR) and marginal return (MR) indicated that these parameters were significantly affected (p N (41.3 kg grain kg−1∙N) and AEN (29.4 kg grain kg−1∙N) were obtained in the 30 kg∙N∙ha−1 plots, while the highest VCR (2.8) and MR (SLL 1.8 SLL−1 spent on N) were obtained in the 180 kg∙N∙ha−1. The significant influence of variety and nitrogen on traits suggests that increasing yields and maximizing profits require use of appropriate nitrogen fe

关键词： Nitrogen Rates Genetic and Agronomic Estimates Introduced Genotypes Grain Yield Zea mays

A Survey of VASNET Framework to Provide Infrastructure-Less Green IoTs Communications for Data Dissemination in Search and Rescue Operations

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Journal of Electronic Science and Technology 2016年第3期14卷 220-228页

作者： Mohamad Nazim Jambli Adnan Shahid Khan sia Chiu Shoon the Faculty of Computer Science and Information Technology Universiti Malaysia Sarawak94300 Kota SamarahanMalaysia

implementation of wireless technologies based on the vehicular ad hoc sensor network （VASNET） may provide support for the search and rescue （SAR） team to operate effectively in natural disaster events, such as landslide, earthquake, flooding, and tsunami. The operations of SAR team are very challenging in such events due to the possible damages of the existing telecommunication infrastructures. The existing deployment of the cellular communications infrastructure may be partially or completely destroyed after the occurrence of these natural disasters. Thus, the current VASNET infrastructure must be able to support the infrastructure-less network by integrating other green wireless technologies that can benefit the SAR team, which can indirectly save more human lives and reduce the number of casualties. Therefore, the integration of green Internet of things （loT） and VASNET is proposed to form a heterogeneous framework for data dissemination in SAR operations. In addition, this paper also discusses the existing lot framework in disaster scenarios with future research direction for IoT using on any aspect, especially related to the natural disaster scenarios.

关键词： Framework green Internet of things (loT) SAR operations vehicular ad hoc sensor network (VASNET).

Discover and Unfold the Mystery of Chinese Medicine

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Chinese Medicine and Culture 2019年第2期2卷 93-94页

作者： Sng Kim sia Lin Xun Department of Postgraduate Program International Education CollegeShanghai University of Traditional Chinese MedicineShanghaiChina

This article shares my experience and journey in Chinese Medicine where I started back in 2014 in Malaysia for my bachelor's degree,and subsequently led me in continuing my postgraduate studies in Shanghai University ... 详细信息

关键词： China Chinese medicine experience sharing journey Malaysia

Overview of milling techniques for improving the solubility of poorly water-soluble drugs

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Asian Journal of Pharmaceutical Sciences 2015年第4期10卷 255-274页

作者： Zhi Hui Loh Asim Kumar Samanta Paul Wan sia Heng GEANUS Pharmaceutical Processing Research Laboratory Department of PharmacyNational University of Singapore18 Science Drive 4Singapore 117543Singapore Janssen India Department of PDMS-SMMD-ADJohnson&Johnson Ltd.Higi HouseOpp Ralli WolfLBS MargMulund(W)Mumbai 400080India

Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a“topedown”approach in the production of fine *** drug particulates are especially desired in formulations designed for parenteral,respiratory and transdermal *** drugs after crystallization may have to be comminuted and this physical transformation is required to various extents,often to enhance processability or solubility especially for drugs with limited aqueous *** mechanisms by which milling enhances drug dissolution and solubility include alterations in the size,specific surface area and shape of the drug particles as well as millinginduced amorphization and/or structural disordering of the drug crystal(mechanochemical activation).Technology advancements in milling now enable the production of drug micro-and nano-particles on a commercial scale with relative *** review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of *** information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

关键词： Drug solubility Fluid energy milling Ball milling Media milling High pressure homogenization Cryomilling

The COVID-19 Pandemic:Global Asymmetries and Challenges for the Future of Health

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China CDC weekly 2021年第7期3卷 140-141页

作者： Nísia Trindade Lima Carlos Grabois Gadelha Oswaldo Cruz Foundation-Fiocruz

The coronavirus disease 2019(COVID-19)pandemic reveals economic,social,and environmental trends that have been present since the last two decades,and it is characterized as a new phenomenon that qualitatively alters contemporary global and national dilemmas—not only because it was caused by a hitherto unknown virus,but by the magnitude of the crisis and the transformations that shape the *** marks a disruptive and threatening historical period in the face of the foundations of modern sociability built during the post-war period.

关键词： COV demic contemporary