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Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： Yan Liang Song Chen Xin dong tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor localization.However,the construction of the fingerprint database is quite time-consuming.Especially when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is difficult.An appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)applications.In this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization accuracy.Reference points(RPs)are generated in the grid by the FGGC model.Then,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex environments.As a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous methods.The proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy simultaneously.The mean error of the proposed model is 0.36 m,far lower than that of previous approaches.Thus,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor localization.It also shows high-accuracy performance with a fast running speed even under a large-size grid.The results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

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Experimental study on effects of gas flow rate on soot characteristics in diffusion flames coupled with plasma

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Science China(Technological Sciences) 2024年第2期67卷 475-485页

作者： QI DanDan CHEN MingXiao tu Xin LIU dong MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China Department of Electrical Engineering and Electronics University of LiverpoolLiverpool L693GJUK

This study examined the evolution of morphology and nanostructure of soot particles from the plasma-flame interaction for various gas flow rates.The current study used both optical diagnostic and sampling methods to explore the soot production and combustion characteristics.Soot particles were characterized at the same positions downstream from the flame zone by thermophoretic sampling and transmission electron microscopy.Moreover,X-ray diffraction analysis,and thermogravimetric analysis were performed to study the nanostructure and oxidation reactivity of soot.A reduction in soot concentration was found with the plasma addition,which illustrated an inhibition effect of plasma on soot emission.The increased gas flow rate promoted soot concentration since a growing number of carbons participated in the combustion process.Depending on the gas flow rate(carbon content)variation and plasma activation,either liquid-like soot material with irregularly shaped protrusions or chain-like structure,or a mixture of both,were generated from the diffusion flames.The soot produced by plasma-flame interaction also demonstrated a high correlation between nanostructure and reactivity.The soot from lower carbon content with plasma activation had a shorter fringe length and larger fringe tortuosity related to higher oxidation reactivity.On the contrary,soot from the highest carbon content without plasma-flame interaction exhibited prevalent fullerene-like nanostructures with evident large or small shells and also had a higher carbonization degree resulting in lower oxidation reactivity.

关键词： soot characteristics gas flow rate plasma diffusion flames

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Overexpression of auxin/indole-3-acetic acid gene MdIAA24 enhances Glomerella leaf spot resistance in apple(Malus domestica)

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Horticultural Plant Journal 2024年第1期10卷 15-24页

作者： Qian Wang dong Huang Wenyan tu Fengwang Ma Changhai Liu State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China

Auxin is throughout the entire life process of plants and is involved in the crosstalk with other hormones,yet its role in apple disease resistance remains unclear.In this study,we investigated the function of auxin/indole-3-acetic acid(IAA)gene Md IAA24 overexpression in enhancing apple resistance to Glomerella leaf spot(GLS)caused by Colletotrichum fructicola(Cf).Analysis revealed that,upon Cf infection,35S::Md IAA24 plants exhibited enhanced superoxide dismutase(SOD)and peroxidase(POD)activity,as well as a greater amount of glutathione(reduced form)and ascorbic acid accumulation,resulting in less H_(2)O_(2)and superoxide anion(O_(2)^(-))in apple leaves.Furthermore,35S::Md IAA24 plants produced more protocatechuic acid,proanthocyanidins B1,proanthocyanidins B2 and chlorogenic acid when infected with Cf.Following Cf infection,35S::Md IAA24 plants presented lower levels of IAA and jasmonic acid(JA),but higher levels of salicylic acid(SA),along with the expression of related genes.The overexpression of Md IAA24 was observed to enhance the activity of chitinase andβ-1,3-glucanase in Cfinfected leaves.The results indicated the ability of Md IAA24 to regulate the crosstalk between IAA,JA and SA,and to improve reactive oxygen species(ROS)scavenging and defense-related enzymes activity.This jointly contributed to GLS resistance in apple.

关键词： Apple MdIAA24 Glomerella leaf spot(GLS) Antioxidant capacity Auxin Salicylic acid Jasmonic acid

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Different mechanisms underlie similar species-area relationships in two tropical archipelagoes

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Plant Diversity 2024年第2期46卷 238-246页

作者： Shengchun Li Tieyao tu Shaopeng Li Xian Yang Yong Zheng Liang-dong Guo Dianxiang Zhang Lin Jiang Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China ECNU-Alberta Joint Lab for Biodiversity Study Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China School of Biological Sciences Georgia Institute of TechnologyAtlantaGA 30332USA Jiangxi Academy of Forestry Nanchang 330032China Institute of Eco-Chongming(IEC) Shanghai 202162China State Key Laboratory of Biocontrol School of EcologySun Yat-sen UniversityGuangzhou 510275China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

Despite much research in the field of island biogeography,mechanisms regulating insular diversity remain elusive.Here,we aim to explore mechanisms underlying plant species-area relationships in two tropical archipelagoes in the South China Sea.We found positive plant species-area relationships for both coral and continental archipelagoes.However,our results showed that different mechanisms contributed to similar plant species-area relationships between the two archipelagoes.For coral islands,soil nutrients and spatial distance among communities played major roles in shaping plant community structure and species diversity.By contrast,the direct effect of island area,and to a lesser extent,soil nutrients determined plant species richness on continental islands.Intriguingly,increasing soil nutrients availability(N,P,K)had opposite effects on plant diversity between the two archipelagoes.In summary,the habitat quality effect and dispersal limitation are important for regulating plant diversity on coral islands,whereas the passive sampling effect,and to a lesser extent,the habitat quality effect are important for regulating plant diversity on continental islands.More generally,our findings indicate that island plant species-area relationships are outcomes of the interplay of both niche and neutral processes,but the driving mechanisms behind these relationships depends on the type of islands.

关键词： Coral and continental islands Plant diversity Soil nutrients Species-area relationships The sampling effect

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Complicated Bosworth fracture-dislocation:A case report and review of the literature

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Chinese Journal of Traumatology 2023年第6期26卷 344-350页

作者： dong-peng tu Li-Jun Cai Hong-Yong Zhao Li-Gang Huang Jing Nie Department of Orthopaedics Hangzhou Xiaoshan Orthopaedic Hospital of Traditional Chinese MedicineHangzhou311261China

Bosworth fracture and dislocation is relatively rare,accounting for about 1%of ankle fractures.It is characterized by the proximal fibula fracture embedded in the posterolateral distal tibia.Due to an insufficient understanding of this fracture,it is easy to cause missed diagnosis and misdiagnosis in clinical practice.Due to the insertion of the fracture,it is challenging to perform closed reduction,and improper treatment is easy to cause complications.Surgical treatment is recommended for this type of fracture.In order to improve the understanding of orthopedic surgeons about Bosworth fracture and dislocation,this paper reports the diagnosis and treatment of 2 cases of Bosworth fracture and dislocation,and reviews the literature on Bosworth fracture's mechanism,diagnosis,classification,complications,and treatment options in recent years.

关键词： Bosworth fracture Ankle fractures Fracture-dislocation

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Rapid Simultaneous Determination of Four Ganoderic Acids in Ganoderma(Chinese Name:Lingzhi)by Direct Infusion-Multiple Reaction Monitoring Cubed

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Journal of Analysis and Testing 2024年第1期8卷 52-62页

作者： Nian Wu Bo peng Ting Li pengfei tu Shengpeng Wang Bo Li Wenjing Liu Yuelin Song Modern Research Center for Traditional Chinese Medicine Beijing Research Institute of Chinese MedicineBeijing University of Chinese MedicineBeijing 100029China Amway(China)Botanical Research Center Wuxi 214011China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipa 999078China Amway(Shanghai)Innovation&Science Co. LtdShanghai 201508China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China

Attributing to the rapid demand expansion for the edible medicinal materials in the market,the limited throughput of highperformance liquid chromatography-multiple reaction monitoring(HPLC-MRM)cannot fully address the measurement workload for a huge number of testing samples.Hence,it is urgent to pursue more efficient approaches for the quality evaluation.Because of the greater selectivity of MRM cubed(MRM^(3))over MRM,there might be a chance to omit the time-intensive LC separation.In current study,we attempted to develop a direct infusion(DI)-MRM^(3) program,and the applicability was thereafter assessed through simultaneous determination of four ganoderic acids(GAs)in one of the most famous tonic herbal medicines namely Ganoderma(Chinese name:Lingzhi).Primary parameters such as Q1>Q3>QLIT ion transitions,collision energy(CE),and excitation energy were optimized by programming online energy-resolved mass spectrometry with authentic compounds.A single DI-MRM measurement merely costed four minutes,and in spite of the wide occurrences of isomers,satisfactory selectivity was achieved.Method validation assays demonstrated the method to be sensitive,precise,accurate,and reproducible.The quantitative results from DI-MRM^(3) were also justified by conducting LC-MRM measurements in parallel.Significant differences occurred for the content patterns between the two original sources namely Ganoderma lucidum and G.sinense,and,moreover,either cultivar or harvest time showed dramatical influence on the quantitative features of the four targeted GAs.More importantly,DI-MRM3 is a meaningful analytical option for rapid quantitative analysis of herbal medicines,because of the comparable reliability,nonetheless,less consumptions of both measurement time and solvent,compared with LC-MRM.

关键词： Direct infusion Multiple reaction monitoring cubed High-throughput quantitative analysis Ganoderic acids Ganoderma

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Efficacyand Safetyof Huashi Baidu Granules in Treating Patients with SARS-CoV-2Omicron Variant: A Single-Center Retrospective Cohort Study

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Chinese Journal of Integrative Medicine 2024年第2期30卷 107-114页

作者： CHEN Cai-yu ZHANG Wen XU Xiang-ru PU Yu-ting tu Ya-dan peng Wei YAO Xuan ZHOU Shuang FANG Bang-jiang Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai(200032)China Department of Classical Traditional Chinese Medicine Chongqing Hospital of Traditional Chinese MedicineChongqing(400021)China Acupuncture and Massage College Shanghai University of Traditional Chinese MedicineShanghai(201203)China Institute of Emergency and Critical Care Medicine Shanghai University of Traditional Chinese MedicineShanghai(200032)China

Objective:To evaluate the efficacy and safety of Huashi Baidu Granules(HSBD)in treating patients with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant.Methods:A single-center retrospective cohort study was conducted during COVID-19 Omicron epidemic in the Mobile Cabin Hospital of Shanghai New International Expo Center from April 1st to May 23rd,2022.All COVID-19 patients with asymptomatic or mild infection were assigned to the treatment group(HSBD users)and the control group(non-HSBD users).After propensity score matching in a 1:1 ratio,496 HSBD users of treatment group were matched by propensity score to 496 non-HSBD users.Patients in the treatment group were administrated HSBD(5 g/bag)orally for 1 bag twice a day for 7 consecutive days.Patients in the control group received standard care and routine treatment.The primary outcomes were the negative conversion time of nucleic acid and negative conversion rate at day 7.Secondary outcomes included the hospitalized days,the time of the first nucleic acid negative conversion,and new-onset symptoms in asymptomatic patients.Adverse events(AEs)that occurred during the study were recorded.Further subgroup analysis was conducted in vaccinated(378 HSBD users and 390 non-HSBD users)and unvaccinated patients(118 HSBD users and 106 non-HSBD users).Results:The median negative conversion time of nucleic acid in the treatment group was significantly shortened than the control group[3 days(IQR:2-5 days)vs.5 days(IQR:4-6 days);P<0.01].The negative conversion rate of nucleic acid in the treatment group were significantly higher than those in the control group at day 7(91.73%vs.86.90%,P=0.014).Compared with the control group,the hospitalized days in the treatment group were significantly reduced[10 days(IQR:8-11 days)vs.11 days(IQR:10.25-12 days);P<0.01].The time of the first nucleic acid negative conversion had significant differences between the treatment and control groups[3 days(IQR:2-4 days)vs.5 days(IQR:4-6 days);P<0.01].The incidence of new-onset sym

关键词： Huashi Baidu Granule severe acute respiratory syndrome coronavirus 2 Omicron variant retrospective cohort trial Chinese medicine

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Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

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Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping Huang Yong-Jiang Wang Meng-Ling tu Junheng Li Bingyan Xu Guoqing peng Jing Yang Sheng-Xiong Huang State Key Laboratory of Phytochemistry and Plant Resources in West China and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for Economic Plants and Biotechnology Kunming Institute of Botany Chinese Academy of Sciences

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity. Given that two C-10 modified camptothecin derivatives,topotecan and irinotecan, have been approved as potent anticancer agents, there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g., C-9, C-10, etc.).However, contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold, thereby limiting the development of modified derivatives. Reported herein, we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa, via metabolomic and transcriptomic analysis. These consist of a cytochrome P450(Nt CPT9H) which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin, as well as two methyltransferases(Nt OMT1/2, converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5, decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin). Importantly, the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis experiments. This work provides a genetic basis for producing camptothecin derivatives through metabolic engineering. This will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis

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Isolation,identification,and virulence gene analysis of pathogenic Aeromonas dhakensis in Macrobrachium rosenbergii and histopathological observation

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Journal of Oceanology and Limnology 2024年第2期42卷 664-675页

作者： Xin peng Haihui tu Xinyi YAO Xuan LAN Zhenxiao ZHONG Jinping LUO Qiongying TANG Shaokui YI Zhenglong XIA Guoliang YANG Zhejiang Provincial Key Laboratory of Aquatic Resources Conservation and Development College of Life SciencesHuzhou UniversityHuzhou 313000China Jiangsu Shufeng Prawn Breeding Co. Ltd.Gaoyou 225654China

To identify the cause of mass mortality of adult Macrobrachium rosenbergii in a farm in Gaoyou City,Jiangsu Province,China,a dominant strain named DKQ-1 was isolated from the hepatopancreas of dying M.rosenbergii and identified as Aeromonas dhakensis by purification culture,biochemical characterization,and 16S rRNA and gyrB gene sequence analysis.The results of the challenge test revealed that the strain was highly pathogenic and the 50%lethal dose(LD_(50))in 72 h to M.rosenbergii was 1.54×10^(5)CFU/mL.The amplification results of virulence genes show that strain DKQ-1 carried 9 virulence genes,including ascV,aexT,aer,act,lip,ompAI,gcaT,acg,and exu,supporting the strong virulence of strain DKQ-1 to M.rosenbergii.Histopathological observation of the hepatopancreas,gills,and intestines indicated that DKQ-1 injection into M.rosenbergii could cause serious tissue damage,which further supported the strong virulence of this strain.In addition,a drug susceptibility test revealed that strain DKQ-1 was sensitive to 16 kinds of antibiotics,resistant to 9 kinds of antibiotics,and had intermediate resistance to spectinomycin and kanamycin.This study is the first report of A.dhakensis isolated from M.rosenbergii and provided a reference for the pathogen identification of bacterial diseases in M.rosenbergii,and for the prevention and treatment caused by A.dhakensis.

关键词： Aeromonas dhakensis histopathology virulence gene gyrB drug susceptibility test Macrobrachium rosenbergii

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China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-Jun tu Long-De Wang 无 Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable disease.According to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a result.Additionally,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in 2020.As the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,respectively.The“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from 2013.Data from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted during 2020.Of those,over 80.0%(81.9%)were ischemic

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

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