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pH-triggered cancer-targeting polymers:From extracellular accumulation to intracellular release

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Nano Research 2023年第4期16卷 5155-5168页

作者： rizwan ullah Khan Jinning Shao Jia-Yu Liao Linghui Qian Institute of Drug Metabolism and Pharmaceutical Analysis Zhejiang Province Key Laboratory of Anti-Cancer Drug ResearchCollege of Pharmaceutical SciencesCancer Center&Hangzhou Institute of Innovative MedicineZhejiang UniversityHangzhou 310058China

Stimuli-responsive polymers are promising to achieve targeted delivery,improved stability during circulation,and controlled release of therapeutic and diagnostic *** them,pH-responsive polymeric nanocarriers have attracted significant attention as pH varies in different body fluids(e.g.,stomach,intestine,and colon)and intracellular organelles(e.g.,endosome,lysosome,and mitochondria)to maintain homeostasis,while distinctive pH changes are also found in certain pathological *** example,the extracellular environment of the tumor is acidic,which can be employed to drive selective *** the internalization process,since most nanocarriers enter cells upon endocytosis where a drop of pH from 6.5 to 5.0 can occur from endosome to lysosome,pH-sensitive groups have been developed for enhanced cargo *** this review,both non-covalent and covalent interactions responsive to pH changes are introduced,with a focus on the structure-property relationship and their applications in cancer targeting and endosomal escape.

关键词： cancer targeting pH-responsive structure-property relationship charge shifting acid-labile linkage

Supportive tactics for innovative and sustainability performance in emerging SMEs

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Financial Innovation 2021年第1期7卷 1824-1854页

作者： Farid ullah Ma Degong Muhammad Anwar Saddam Hussain rizwan ullah School of Economics Sichuan UniversityChengduChina Department of Economics ROKHAN Institute of Higher EducationJalalabadAfghanistan Head of Financial Engineering Department School of EconomicsSichuan UniversityChengduChina Witten Institute for Family Business Witten/Herdecke UniversityWittenGermany Institute of Management Studies University of PeshawarPeshawarPakistan Capital University of Science and Technology IslamabadPakistan

For this research,we examined the influence of access to domestic and international financing on sustainability performance with a mediating role of innovative performance and a moderating role of access to government *** were collected from 317 small and medium-sized enterprises(SMEs)through structured *** results indicated that access to domestic and international financing significantly contributes to sustainability and innovative ***,we found a partial mediating role of innovative performance between access to domestic financing and sustainability performance as well as between access to international financing and sustainability *** to government support significantly moderates the relationship between access to domestic finances and innovative performance as well as between access to international finances and innovative *** and policymakers should encourage national and international financial institutions and banks to facilitate SMEs by lending them funds for innovative activities and sustainability ***,the government should support SMEs,so that they can contribute to economic growth and the gross domestic *** implications from these matters will be further discussed in this paper.

关键词： Domestic finance Government support International finance Foreign direct investment Innovative performance Sustainability SMEs

Th-Shaped Tunable Multi-Band Antenna for Modern Wireless Applications

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Computers, Materials & Continua 2023年第2期74卷 2517-2530页

作者： Wasi Ur Rehman Khan Muhammad Fawad Khan Muhammad Irfan Sadiq ullah Naveed Mufti Usman Ali rizwan ullah Fazal Muhammad Saifur Rahman Faisal Althobiani Mohammed Alshareef Mohammad E.Gommosani Department of Telecommunication Engineering University of Engineering and TechnologyMardanPakistan Electrical Engineering Department College of EngineeringNajran UniversityNajranSaudi Arabia Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Natural Science Department Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia

A compact,reconfigurable antenna supporting multiple wireless services with a minimum number of switches is found lacking in literature and the same became the focus and outcome of this *** was achieved by designing a Th-Shaped frequency reconfigurable multi-band microstrip planar antenna,based on use of a single switch within the radiating structure of the *** frequency bands(i.e.,2007–2501 MHz,3660–3983MHz and 9341–1046 MHz)can be operated with the switch in the ON switch *** the OFF state of the switch,the antenna operates within the 2577–3280MHz and 9379–1033MHz *** proposed antenna shows an acceptable input impedance match with Voltage Standing Wave Ratio(VSWR)less than *** peak radiation efficiency of the antenna is 82%.A reasonable gain is obtained from 1.22 to 3.31 dB within the operating bands is *** proposed antenna supports UniversalMobile Telecommunication System(UMTS)-1920 to 2170 MHz,Worldwide Interoperability and Microwave Access(WiMAX)/Wireless Broadband/(Long Term Evolution)LTE2500–2500 to 2690 MHz,Fifth Generation(5G)-2500/3500 MHz,Wireless Fidelity(Wi-Fi)/Bluetooth-2400 to 2480 MHz,and Satellite communication applications in X-Band-8000 to 12000 *** overall planar dimension of the proposed antenna is 40×*** antennawas designed,along with the parametric study,using Electromagnetic(EM)simulation *** antenna prototype is fabricated for experimental validation with the simulated *** proposed antenna is low profile,tunable,lightweight,cheap to fabricate and highly efficient and hence is deemed suitable for use in modern wireless communication electronic devices.

关键词： Antenna design reconfigurable antenna satellite communication frequency bands

Solid state reaction for the formation of spinel MgFe_2O_4 across perovskite oxide interface

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Science China(Physics,Mechanics & Astronomy) 2017年第9期60卷 80-84页

作者： Iftikhar Ahmed Malik XiaoXing Ke Xin Liu ChuanShou Wang XueYun Wang rizwan ullah ChuangYe Song Jing Wang JinXing Zhang Department of Physics Beijing Normal University Institute of Microstructure and Property of Advanced Materials Beijing University of Technology Department of Physics University of Science and Technology Beijing

Solid state reaction is a conventional method to synthesize structurally stable inorganic solids by mixing powdered reactants together at high pressure （over 1 x 105 mbar （1 mbar = 100 Pa）） and high temperature （over 1300 K） [1-4]. This method is effective and sophisticated to prepare solid mate- rials, especially the functional complex oxides such as high temperature superconductors, piezoelectrics, dielectrics, etc. However, the chemical reactions cannot be intrinsically con- trolled and integrated at an atomic level in order to achieve the applications of future thin film devices with reduced dimensions [5]. With the desire of designing high-quality products with the micro/nanoscale integration, many pow- erful physical techniques, such as, pulsed-laser deposition （PLD）, molecular beam epitaxy （MBE）, sputtering deposi- tion, etc., have experienced enormous development due to their ability of lattice and/or interfacial controls. Using these growth techniques, layer-by-layer deposition （multilayer and/or superlattice） can be achieved, providing us a platform to tune the crystal structures at an atomic level by controlling the interfacial terminations and epitaxial strain, which are absent in their bulk counterparts [6-8]. From this point of view, well-controlled interfacial structures may also provide the solid state reaction at an atomic level during the physical depositions, which provides us an effective way to design the desired products from the chemical bonding reconstruction.

关键词：固相反应界面形成钙钛矿型氧化物 MgFe2O4 尖晶石脉冲激光沉积高温超导体控制界面

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语音信号中敲击按键声音的检测和抑制

语音信号中敲击按键声音的检测和抑制

作者： ullah rizwan 中国科学技术大学

学位级别：硕士

在近几十年来,使用电脑和笔记本电脑在不同的通信场景中录制音频已经有了显著增加,如讲座、会议、视频会议和互联网协议语音通信。一些人使用电脑和笔记本采集讲座音频用于存档,另一些人使用录音机来存档。由于键盘靠近麦克风,导致录制... 详细信息

在近几十年来,使用电脑和笔记本电脑在不同的通信场景中录制音频已经有了显著增加,如讲座、会议、视频会议和互联网协议语音通信。一些人使用电脑和笔记本采集讲座音频用于存档,另一些人使用录音机来存档。由于键盘靠近麦克风,导致录制的语音被加性键盘敲击声严重破坏,这些噪声主要来自于机器键盘的打字声。由于敲击声的不平稳性和陡峭性,因此这是一个在单通道语音增强领域具有挑战性的问题。本文主要是抑制语音信号中的键盘敲击声。提出了两种新颖的用于检测和抑制冲击性键盘敲击声的两步算法,即基于相关技术的稀疏非负矩阵分解(SNMF-CR)和基于阈值技术的稀疏非负矩阵分解(SNMF-TT)。在这两种方法中,第一步都是用稀疏非负矩阵分解完成的。在第二步中提出了两种新的算法。在SNMF-CR中,从第一步中(SNMF阶段)估计得到的干净语音与原始带噪语音之间做相关。根据原始带噪语音中的噪声损坏段与估计干净语音中的噪声抑制段之间的低相关系数,原始带噪语音中的噪声段被来自第一步估计的干净语音中的相应噪声抑制段替换。在基于阈值的技术中,根据敲击声的能量比普通语音的频率轴分布更广泛的特点,将整个频谱图水平分为上下两部分。将高频能量的范数除以低频能量的范数,得到的比率跟门限比较从而用于检测键盘敲击声。在原始带噪语音中检测到的键盘敲击声片段被相应的由第一步估计的干净语音片段替代。因此,这两种方法中,没有被键盘敲击声破坏的语音段都被保留不变。在带噪的语音段,键盘噪声被抑制了但是语音质量并未下降。因此抑制敲击声后没有带来严重的语音失真,这是本论文的创新点。提出的算法主要和谱减法、增强的OM-LSA算法对比,所提出的算法具有更好的性能。

关键词：单通道语音增强短时傅立叶变换有监督稀疏非负矩阵分解相关性按键声音抑制阈值技术

Cactus-Shaped Frequency Reconfigurable Antenna for Sub 10 GHz Wireless Applications

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Computer Systems Science & Engineering 2023年第6期45卷 2693-2704页

作者： Muhammad Irfan Wasi Ur Rehman Khan Sadiq ullah Naveed Mufti Muhammad Fawad Khan rizwan ullah Usman Ali Fazal Muhammad Faisal Althobiani Mohammed Alshareef Shadi Alghaffari Saifur Rehman V.R.Shamji Electrical Engineering Department College of EngineeringNajran UniversitySaudi Arabia Department of Telecommunication Engineering University of Engineering and TechnologyMardanKPPakistan Department of Electrical Engineering University of Engineering and TechnologyMardanKPPakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Faculty of Maritime Studies King Abdulaziz UniversityJeddahSaudi Arabia

This paper presents,a novel cactus shaped frequency reconfigurable antenna for sub 10 GHz wireless *** diode is utilized as an electrical switch to achieve reconfigurability,enabling operation in four different frequency *** the switch ON state mode,the antenna supports 2177-3431 and 6301-8467 MHz ***,the antenna resonates within 2329-3431 and 4951-6718 MHz while in the OFF state *** efficiency values,ranging from 68%to 84%,and gain values,ranging from 1.6 to 4 dB,in the operating frequency *** proposed antenna satisfy the practical requirements and *** overall planner dimensions of the proposed antenna model is 40×21 mm^(2).Moreover,the measurement results from the prototype support the simulation *** on the frequency ranges supported by the antenna,it can be used for multiple wireless standards and services,including Worldwide interoperability and Microwave Access(WiMAX),Wireless Fidelity(Wi-Fi),Bluetooth,Long Term Evolution(LTE)and satellite *** increases its applicability for use in mobile terminals.

关键词： Antenna frequency reconfigurable PIN diode switch wireless technology

A Review on the Management of Gestational Diabetes Mellitus(GDM):Pharmacological and Non-Pharmacological Interventions

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Journal of Clinical and Nursing Research 2022年第4期6卷 75-82页

作者： Muhammad Khalid Khan rizwan ullah Baig Drug Delivery and Cosmetics Lab(DDCL) Faculty of PharmacyGomal UniversityDera Ismail Khan 27050Pakistan Department of Pharmacy Quaid-E-Azam UniversityIslamabad 44000Pakistan

Gestational diabetes mellitus(GDM)is defined as any degree of glucose or carbohydrate intolerance mainly during *** 10%to 15%of pregnancies are affected and complicated by gestational *** to hormonal changes during pregnancy,the requirement for insulin increases,and thus the usual concentration of insulin previously catered for glycemic control is *** order to meet the body’s demand,the islet cells secrete a higher amount of *** occurs when this higher concentration is also unable to control blood *** increased resistance toward insulin is most noticeable during the third trimester of pregnancy,which gradually normalizes after the termination of *** complications do arise,which affect both the mother and her developing *** the mother,miscarriages,delivery of baby via caesarian section,and other complications may result,whereas the fetus may be affected with congenital abnormalities,neonatal hypoglycemia,and even *** of GDM includes both non-pharmacological and pharmacological *** agents are employed when non-pharmacological interventions fail to achieve the desired ***,insulin,and metformin are the commonly used pharmacological agents.

关键词： Gestational diabetes mellitus Postprandial glucose Macrosomia OHA Neonatal Pre-eclampsia

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巴基斯坦证券交易所股票波动率研究

巴基斯坦证券交易所股票波动率研究

作者： ullah rizwan（李子安）北京交通大学

学位级别：硕士

本文尝试使用来自卡拉奇证券交易所(最近更名为巴基斯坦证券交易所)(KSE)的数据来模拟新兴市场的条件波动。我们采用了非对称模型,例如E-GARCH(1,1),T-GARCH(1,1)和P-GARCH(1,1)和对称模型,例如ARCH(1),GARCH(1,1)和GARCH-M(1,1),对22... 详细信息

本文尝试使用来自卡拉奇证券交易所(最近更名为巴基斯坦证券交易所)(KSE)的数据来模拟新兴市场的条件波动。我们采用了非对称模型,例如E-GARCH(1,1),T-GARCH(1,1)和P-GARCH(1,1)和对称模型,例如ARCH(1),GARCH(1,1)和GARCH-M(1,1),对22年的每日、每周及每月KSE 100指数回报系列进行了研究,以探讨波动的性质和不同的相关方面。新的经验证据表明,这三个收益序列均显示出具有高峰度和平稳性的非正态分布特性。此外,我们发现波动性很高,并且持续存在,这导致了目前所观察到的冲击的影响,对未来收益的影响持续了更长的时间。最后,事实证明,用于日收益率系列的P-GARCH(1,1)和用于每周数据的GARCH(1,1)模型与波动率建模最符合。

关键词：对称和非对称模型条件波动率卡拉奇证券交易所

Higher Concentrations and Ecological Risks of Selected Persistent Organic Pollutants in Macrobrachium lamarrei from the Streams of Sialkot, Pakistan

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Journal of Agricultural Science and Technology(B) 2016年第1期6卷 27-34页

作者： rizwan ullah Riffat Naseem Malik Ashiq Muhammad Karam Ahad Muhammad Tariq Rehana Asghar Abdul Qadir Department of Zoology Mirpur University of Science & Technology (MUST) Mirpur-10250 (AJK) Pakistan Department of Environmental Sciences Quaid-i-Azam University lslamabad 45320 Pakistan Ecotoxicology Research Programme Institute of Plant and Environmental Protection National Agricultural Research Centre(NARC) Islamabad 44000 Pakistan Department of Biotechnology Mirpur University of Science & Technology (MUST) Mirpur-10250 (AJK) Pakistan Colleve of Earth and Environmental Sciences. University of the Punjab. Lahore 54590. Pakistan

Persistent organic pollutants （POPs） persisting in the environment, which accumulate in human and animal tissue and bio-magnify in food-chains, would have significant impacts on human health and the environment. Thus, the present study was designed to investigate the accumulation of organic pollutants in prawn from streams of Sialkot, Pakistan. Fresh water prawn Macrobrachium lamarrei was captured from streams of study area. Samples were prepared for extraction of selected organic pollutants and then analyzed through gas chromatograph-electron capture detector （GC-ECD）. Results of current study showed that five pesticide residues, i.e., B-HCH, Lindane, DDD, 2, 4-DDT and 4, 4-DDT were detected in composite prawn sample. The rest of POPs residues were not found in prawn. The ratio of a-HCH/γ-HCH indicated an input of technical HCH and long range transport, while the ratio of DDT/（DDD ＋ DDE） showed recent use of DDT to the study area. The high values of TEC-HQ and PEC-HQ of POPs in the studied prawn samples depicted risk posed to health.

关键词： Prawn streams pesticides Sialkot Pakistan.