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Polymer types regulation strategy toward the synthesis of carbonized polymer dots with excitation-wavelength dependent or independent fluorescence

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Chinese Chemical Letters 2023年第2期34卷 388-392页

作者： Jianliang Bai Xinyu Wang Yaqing Zhu Guojun Yuan Shuang Wu Fu Qin Xu Yu Lili Ren school of Chemistry&Chemical Engineering Southeast UniversityNanjing 211189China school of Environment and Chemical Engineering Anhui Vocational and Technical CollegeHefei 230011China

Three kinds of carbonized polymer dots(CPDs) synthesized via a one-pot process from ophenylenediamine(OPD), m-phenylenediamine(MPD) and p-phenylenediamine(PPD) exhibit excitationwavelength independent yellow, green and red emissions, respectively. In sharp contrast, two kinds of CPDs prepared via a hydrothermal process from citric acid(CA) and diethylenetriamine(DETA) exhibit obvious excitation-wavelength dependent emissions. Through the characterization and comparison of the two types of CPDs, it is concretely revealed that the polymer structure types during the formation of CPDs can effectively control the fluorescence excitation-wavelength independence/dependence. The homogeneous polymer structures contained in CPDs contribute to excitation-wavelength independence, whereas random copolymer structures contribute to excitation-wavelength dependence. These studies are of great significance for further understanding the polymer structures and designing unique optical properties of CPDs.

关键词： Carbonized polymer dots Excitation-wavelength dependence Excitation-wavelength independence Homogeneous polymer structures Random polymer structures

Structure-based discovery of orally efficient inhibitors via unique interactions with H-pocket of PDE8 for the treatment of vascular dementia

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Acta Pharmaceutica Sinica B 2022年第7期12卷 3103-3112页

作者： Xu-Nian Wu Qian Zhou Ya-Dan Huang Xi Xie Zhe Li Yinuo Wu Hai-Bin Luo school of Pharmaceutical Sciences Sun Yat-sen UniversityGuangzhou510006China Key Laboratory of Tropical Biological Resources of Ministry of education and One health Institute School of Pharmaceutical SciencesHainan UniversityHaikou 570228China

Our previous study demonstrated that phosphodiesterase 8(PDE8)could work as a potential target for vascular dementia(Va D)using a chemical probe ***,compound 3a is a chiral compound which was obtained by chiral resolution on HPLC,restricting its usage in ***,a series of non-chiral 9-benzyl-2-chloro-adenine derivatives were discovered as novel PDE8 *** 15 exhibited potent inhibitory activity against PDE8A(IC_(50)=11 nmol/L),high selectivity over other PDEs,and remarkable drug-like properties(worthy to mention is that its bioavailability was up to 100%).Oral administration of 15 significantly improved the c AMP level of the right brain and exhibited dosedependent effects on cognitive improvement in a Va D mouse ***,the X-ray crystal structure of the PDE8A—15 complex showed that the potent affinity and high selectivity of 15 might come from the distinctive interactions with H-pocket including T-shapedπ—πinteractions with Phe785 as well as a unique H-bond network,which have never been observed in other PDE-inhibitor complex before,providing new strategies for the further rational design of novel selective inhibitors against PDE8.

关键词： Phosphodiesterase 8(PDE8) Vascular dementia Structure-based drug design MM-GB/SA Free energy prediction Structure—activity relationship Binding potencies

Research Status of Serum Pharmacology and Serum Pharmacochemistry of Traditional Chinese Medicine

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Agricultural Biotechnology 2021年第1期10卷 126-128页

作者： Qun CHEN Ling HUANG Rui WANG Cong PANG school of Continuing education Bozhou Vocational and Technical CollegeBozhou 236800China

Serum pharmacochemistry of traditional Chinese medicine has become a more accurate and rapidly developing reasonable way to analyze the effective material basis of traditional Chinese medicine in recent years. Through this method, we can select very complex Chinese medicine components and clarify the effective substances consistent with the main functions, and then separate and purify effective ingredients in traditional Chinese medicine, so as to explain the material basis of the drug effect and prove the rationality and principle of action of Chinese medicine compounds. It can show the multi-component and multi-target characteristic of traditional Chinese medicine, and after analyzing the migrating components of serum, we can explore the direct effective substances that act on the patient’s body, so as to accelerate and accurately complete the in-depth study of the effective substances of Chinese medicine.

关键词： Traditional Chinese Medicine Field Serum pharmacology Serum pharmacochemistry Application overview Chinese herbal compound

Structural Effects of L16Q, S20G, and L16Q-S20G Mutations on hlAPP： A Comparative Molecular Dynamics Study

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Chinese Journal of Chemistry 2012年第2期30卷 241-248页

作者： Wang,Mian Yang,Jipeng Wang,Jianyi Wang,Xiaojuan school of Chemistry and Chemical Engineering Guangxi UniversityNanningGuangxi 53004China Jiyuan vocational and Technical College JiyuanHenan 459000China

The conformation change picture of human islet amyloid polypeptide （hlAPP） is outlined using molecular dynamics simulation, and the structural influences of L16Q, S20G, and L16Q-S20G mutations on the conformation of hlAPP are analyzed. Particularly, the conformational changes of the amyloidogenic-related regions of residues 15-- 17 and 20--29 are emphasized. Our studies find that, for WT hlAPP, residues 15--17 always maintain a stable a-helix structure, residues 20--25 structurally fluctuate between turn and 5-helix, and residues 26--29 mainly adopt coil and bend structures. The hydrogen bonds between the polar groups of hlAPP, long-rang van der Waals forces between the residues, and hydrophobic interactions between the residues of hlAPP are important driving forces to maintain the secondary structure of hlAPP. The replacement of leucine 16 by glutamine stabilizes the helix structure of residues 15--17 and 20--23 of hlAPP monomer, and the structure of residues 24--29 fluctuates be- tween helix and turn. The relatively stable helix structures of residues 15--17 and 20--29 are supposed to be beneficial for L16Q hlAPP to resist the aggregation as observed in the experiment. The substitution of serine20 by glycinc drives residues 15--17 and 20--29 of hlAPP to transform from helix structure to β-strands or coil structures with higher extension and flexibility, which may promote the aggregation of hlAPP as the experiments reported. These results are significant to understand the aggregation mechanism of hlAPP monomer into the dimer, trimer, oligomers and fibrils associated with the type 2 diabetes at the atomic level.

关键词： hIAPP wild type mutant molecular dynamics simulation

Determination of Antimicrobial Activity of Methyl Cellulose Films Enriched with Some Essential Oils on Listeria innocua

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Journal of Earth Science and Engineering 2013年第12期3卷 834-839页

作者： Selin Kalkan Zerrin Erginkaya Emel Unal Osmaniye Korkut Ata University Bahce Vocational School of Higher Education Department of Food Technology Osmaniye 80500 Turkey Cukurova University Faculty of Agriculture Department of Food Engineering Adana 01330 Turkey

Essential oils are effective antimicrobials on important some pathogenic bacteria and can be added packaging materials due to absorb various surfaces. In this study, the aim is to determinate of antimicrobial effects of methyl cellulose films with containing various proportions thyme, rosemary, coriander, basil and pimento berry oils （1%, 2%, 3% and 4% g/cc） against important bacteria as a surface contaminant Listeria innocua by in vitro. For this purpose, 1 cm diameter discs were cut from methyl cellulose films containing essential oils and inhibition zone diameter which were measured by the agar diffusion method. As the results of these analyses, all prepared active edible methyl cellulose films were antimicrobial effects on Listeria innocua. The most powerful antimicrobial effect achieved with methyl cellulose film including coriander oil on Listeria innocua. And also the weakest antimicrobial effect achieved with methyl cellulose film including rosemary oil on Listeria. All results were significant by statistically （p 〈 0.01） and all analyses were replicated in three times.

关键词： Antimicrobial activity methyl cellulose edible film Listeria innocua.

Optimal user scheduling and power control in multi-user cognitive broadcast systems

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Science China(Information Sciences) 2012年第6期55卷 1402-1414页

作者： WANG QunHuan 1,2,3,WANG HuiMing 1,2,3 & YIN QinYe 1,3 1 school of Electronic and Information Engineering,Xi'an Jiaotong University,Xi'an 710049,China 2 State Key Lab for Integrated services Networks,Xidian University,Xi'an 710071,China 3 Ministry of education Key Lab for Intelligent Networks and Network Security,Xi'an Jiaotong University,Xi'an 710071,China. school of Electronic and Information Engineering Xi"an Jiaotong University State Key Lab for Integrated services Networks Xidian University Ministry of education Key Lab for Intelligent Networks and Network Security Xi"an Jiaotong University

Cognitive radio systems should not only have the ability to sense and exploit "frequency spectrum holes",but also the ability to sense and utilize "spatial spectrum holes".In this paper,we consider the issue of maximizing the throughput of the cognitive systems by fully utilizing "spatial spectrum holes" brought in by multiple cognitive users,in the scenario where a pair of licensed users and a cognitive broadcast system share multiple spectrum *** exploiting the channel reciprocity under the premise that the licensed system adopts the time-division-duplexing (TDD) mode,we propose a more practical cognitive access scheme that can sense the interference at the licensed user caused by the cognitive transmitter,based on the existing feedback signals from the licensed user to the licensed base *** both interferences from the licensed base station to the cognitive receiver and from the cognitive transmitter to the licensed user into consideration,we investigate the optimal user scheduling and power allocation scheme that can maximize the ergodic sum rate of the cognitive *** show that scheduling the user whose channel gain to interference and noise ratio (CGINR) is the largest for each frequency band is *** also derive the dynamic power allocation scheme meeting the three practical constraints,i.e.,the transmitter's average transmission power constraint,the power amplifier's instantaneous transmission power constraint,and the interference power constraint at the licensed *** result shows that in different coherent time intervals and different frequency bands,the power allocation has a multi-level waterfilling *** analysis shows that the strategy scheduling user with the largest CGINR introduces significant performance improvement compared with the traditional strategy scheduling user with the largest channel gain to noise ratio (CGNR).We also illustrate the impact of power constraints and the number of users on system p

关键词： cognitive radio distributed spatial spectrum holes opportunistic scheduling power allocation

Bio-control of Some Food-Borne Pathogenic Bacteria by Bacteriophage

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Journal of Food Science and Engineering 2011年第4期1卷 237-244页

作者： S. Kalkan E. UEnal Z. Erginkaya Department of Food Technology Bahce Vocational School of Higher Education Osmaniye Korkut Ata University Osmaniye80500 Turkey Department of Food Engineering Faculty of Agriculture Cukurova University Adana 01330 Turkey

In recent years, researchers tended to bring new alternative to biological protective systems used in conservation of food and production of safe food. Use of bacteriophage against to pathogen bacteria in food was the most hopeful system in these methods about bio-control. Controls of bacteriophage for each pathogen species and subspecies and determination of phage-host originality are important because efficient bio-control was achieved. Researches concentrated on some food-borne pathogen bacteria such as E. coli O157：H7, Campylobacter, Salmonella and Listeria. In a consequence of these studies made as in vitro and in vivo, first commercial production of phage which will be used in foods was made in Netherlands. Also, it has been informed that use of phage is cost-efficient alternative as compared with other preservatives. This review, discussed application of bacteriophages as bio-control agents in food and advantages and disadvantages about uses of bacteriophages by taking into account antimicrobial characteristics of them.

关键词： Bacteriophage food-born pathogenic bacteria bio-control antimicrobial food review.

Optimization of energy efficiency for the full-duplex massive MIMO systems

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Journal of Systems Engineering and Electronics 2016年第2期27卷 326-332页

作者： Xinhua Wang Ju Liu Chao Zhai Pengbo Xing Lina Zheng school of Information Science and Engineering Shandong University State Key Laboratory of Integrated services Networks Xidian University

The energy efficiency（EE） for the full-duplex massive multi-input multi-output（MIMO） system is investigated. Given the transmit powers of both the uplink and the downlink, the closed-form solutions of the optimal number of antennas and the maximum EE are achieved in the high regime of the signal-to-noise ratio（SNR）. It is shown that the optimal number of antennas and the maximum EE gets larger with the increase in user numbers. To further improve the EE, an optimization algorithm with low complexity is proposed to jointly determine the number of antennas and the transmit powers of both the uplink and the downlink. It is shown that, the proposed algorithm can achieve the system performance very close to the exhaustive search.

关键词： energy efficiency(EE) full-duplex fractional programming massive multi-input multi-output(MIMO)

Service Functions of Private Community health Stations in China: A Comparison Analysis with Government-sponsored Community health Stations

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2012年第2期32卷 159-166页

作者：侯万里樊宏许静王芳柴云徐汉成李永斌刘利群王斌金建强卢祖洵 school of Public health Tongji Medical College Huazhong University of Science and Technology school of Public health Nanjing Medical University Department of Maternal and Child health Care and Community health Ministry of Health

In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical care services in urban areas. However, only limited evidence is available con-cerning the service functions of private community health facilities in China. The aim of this study was to explore the functions of private community health stations (PCHSs) to provide evidence-based rec-ommendations for policy-making and practice in the development of urban community health services systems. A total of 818 PCHSs and 4320 government-sponsored community health stations (GCHSs) located in 28 cities of China were investigated in 2008. The percentages of stations that provided health services and the annual workload per community health worker (CHW) were compared between the two types of institutions. The results showed that the percentages of PCHSs providing public health services were significantly higher than those of GCHSs (Pservices providing between PCHSs and GCHSs (P>0.05). The annual workloads of all the public health services and basic medical services per CHW in PCHSs were lighter than those in GCHSs (Phealth records establishment and health education materials distribution (P>0.05). At present, the GCHSs are still the mainstream in urban China, which will last for a long period in future. However, our findings showed that the annual workloads of CHWs in PCHSs were no heavier than those in GCHSs, and the PCHSs were willing to provide public health services. In view of current inadequacy of health resources in China, it is feasible to further develop PCHSs under the guidance of the government, given that PCHSs can perform the basic functions of community health services, which is useful for the formation of public-private partnerships (PPP)

关键词： private community health stations government-sponsored community health stations services functions