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Rare earth fluorescent nanoprobes with minimal side effects enable tumor microenvironment activation for chemotherapy

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Journal of Rare Earths 2024年第2期42卷 256-262,I0001页

作者： Tianqi Cao Yuxin Liu Qi Jia Xiaolu Wang Shouqiang Zhang Jing Zhou Department of Chemistry Capital Normal UniversityBeijing100048China

Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for ***,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor *** this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is *** unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe *** addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor *** change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic *** vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in *** work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.

关键词： Rare earth nanoprobes Fluorescence Ratiometric imaging DOX Chemotherapy

Identification of rural courtyards’utilization status using deep learning and machine learning methods on unmanned aerial vehicle images in north china

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Building Simulation 2024年第5期17卷 799-818页

作者： Maojun Wang Wenyu Xu Guangzhong Cao Tao Liu college of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China college of Urban and Environmental sciences Peking UniversityBeijing 100871China

The issue of unoccupied or abandoned homesteads(courtyards)in china emerges given the increasing aging population,rapid urbanization and massive rural-urban *** the aspect of rural vitalization,land-use planning,and policy making,determining the number of unoccupied courtyards is *** and questionnaire-based surveys were currently the main approaches,but these traditional methods were often expensive and laborious.A new workflow is explored using deep learning and machine learning algorithms on unmanned aerial vehicle(UAV)***,features of the built environment were extracted using deep learning to evaluate the courtyard management,including extracting complete or collapsed farmhouses by Alexnet,detecting solar water heaters by YOLOv5s,calculating green looking ratio(GLR)by *** precisions exceeded 98%.Then,seven machine learning algorithms(Adaboost,binomial logistic regression,neural network,random forest,support vector machine,decision trees,and XGBoost algorithms)were applied to identify the rural courtyards’utilization *** Adaboost algorithm showed the best performance with the comprehensive consideration of most metrics(Accuracy:0.933,Precision:0.932,Recall:0.984,F1-score:0.957).Results showed that identifying the courtyards’utilization statuses based on the courtyard built environment is *** is transferable and cost-effective for large-scale village surveys,and may contribute to the intensive and sustainable approach to rural land use.

关键词： unoccupied homesteads courtyard built environment inner courtyard management GLR solar water heaters machine learning algorithms

Integrating host biological and ecological variables to predict probability of haemosporidian infection in raptors

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Avian Research 2024年第2期15卷 255-264页

作者： Kai Gao Xuemei Yang Xi Huang Wenhong Deng Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China

Variations in host traits that influence their exposure and susceptibility may impact probability of vector-transmitted ***,identifying the predictors of infection probability is necessary to understand the risk of disease outbreaks during expanding environmental ***,we conducted a large survey based on microscopic examination and molecular analysis of haemosporidian parasite infection in raptors rescued at the beijing Raptor Rescue *** these data with biological and ecological variables of the raptors,we determined predictors that affect the probability of haemosporidian infection using generalized linear mixed models and multimodel *** results showed that infection probability exhibited considerable variation across host species in raptors,and body mass,sex,and evolutionary history played relatively weaker roles in driving infection ***,activity pattern,age,geographic range size,migration distance,and nest type were important predictors of the probability of haemosporidian infection,and the role of each predictor differed in the three main haemosporidian genera(Plasmodium,Haemoproteus,and Leucocytozoon).This macro-ecological analysis will add to our understanding of host traits that influence the probability of avian haemosporidian infection and will help inform risk of emerging diseases.

关键词： Activity pattern Emerging infectious diseases Infection probability Interspecific variation Migratory exposure

Imaging plate scanners calibration and the attenuation behavior of imaging plate signals

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Chinese Physics B 2024年第6期33卷 38-44页

作者：薄楠王乃彦 college of Nuclear science and Technology Beijing Normal UniversityBeijing 100875China china Institute of Atomic Energy Beijing 102413China

Based on previously reported work, we propose a new method for calibrating image plate(IP) scanners, offering greater flexibility and convenience, which can be extended to the calibration tasks of various scanner models. This method was applied to calibrate the sensitivity of a GE Typhoon FLA 7000 scanner. Additionally, we performed a calibration of the spontaneous signal attenuation behavior for BAS-MS, BAS-SR, and BAS-TR type IPs under the 20±1℃ environmental conditions, and observed significant signal carrier diffusion behavior in BAS-MS IP. The calibration results lay a foundation for further research on the interaction between ultra-short, ultra-intense lasers and matter.

关键词： image plate scanner ultra-short ultra-intense lasers

Programmable repulsive potential for tight-binding from Chen-Möbius inversion theorem

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science china(Physics,Mechanics & Astronomy) 2024年第1期67卷 71-83页

作者： Jian-Gao Li Jin-Kun Tang Hong-Quan Song Gotthard Seifert Dong-Bo Zhang college of Nuclear science and Technology Beijing Normal UniversityBeijing 100875China Department of Physics Beijing Normal UniversityBeijing 100875China college of Physics and Telecommunication Engineering Zhoukou Normal UniversityZhoukou 466001China Theoretische Chemie Technische Universität DresdenDresden D-01062Germany

An accurate total energy calculation is essential in materials *** date,many tight-binding(TB)approaches based on parameterized hopping can produce electronic structures comparable to those obtained using first-principles ***,TB approaches still have limited applicability for determining material properties derived from the total *** is,the predictive power of the TB total energy is impaired by an inaccurate evaluation of the repulsive *** complexity associated with the parametrization of TB repulsive potentials is the weak link in this *** this study,we propose a new method for obtaining the pairwise TB repulsive potential for crystalline materials by employing the Chen-Möbius inversion *** show that the TB-based phonon dispersions,calculated using the resulting repulsive potential,compare well with those obtained by first-principles calculations for various systems,including covalent and ionic bulk materials and twodimensional *** present approach only requires the first-principles total energy and TB electronic band energy as input and does not involve any *** striking feature enables us to generate repulsive potentials programmatically.

关键词： tight binding first-principles calculation total energy repulsive potential phonon dispersion

Decabromodiphenyl ether induces the chromosome association disorders of spermatocytes and deformation failures of spermatids in mice

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Journal of Environmental sciences 2024年第4期138卷 531-542页

作者： Jinglong Xue Xiangyang Li Yafei Chi Leqiang Gao Yue Zhang Yan Wang Moxuan Zhao Jialiu Wei Zhixiong Shi Xianqing Zhou Department of Toxicology and Hygienic Chemistry School of Public HealthCapital Medical UniversityBeijing 100069China beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China Laboratory Animal Center Capital Medical UniversityBeijing 100069China Key Laboratory of Cardiovascular Epidemiology&Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China

The environmental presence of decabromodiphenyl ether(BDE-209),which is toxic to the male reproductive system,is *** current study investigated its mechanism of toxicity in *** results showed,that BDE-209 induced DNA damage,decreased the expression of the promoter of meiosis spermatogenesis-and oogenesis-specific basic helix-loop-helix 1(Sohlh1),meiosis related-factors Lethal(3)malignant brain tumor like 2(L3MBTL2),PIWI-like protein 2(MILI),Cyclin-dependent kinase 2(CDK2),Cyclin A,synaptonemal complex protein 1(SYCP1)and synaptonemal complex protein 3(SYCP3),and caused spermatogenic cell apoptosis,resulting in a decrease in sperm quantity and ***,BDE-209 downregulated the levels of anaphase-promoting complex/cyclosome(APC/C),increased the expression of PIWI-like protein 1(MIWI)in the cytoplasm of elongating spermatids,and decreased the nuclear levels of RING finger protein 8(RNF8),ubiquitinated(ub)-H2A/ub-H2B,and Protamine 1(PRM1)/Protamine 2(PRM2),while increasing H2A/H2B nuclear levels in *** reproductive toxicity was persistent for 50 days following the withdrawal of BDE-209 *** results suggested that BDE-209 inhibits the initiation of meiosis by decreasing the expression of ***,the reduced expression of L3MBTL2 inhibited the formation of chromosomal synaptonemal complexes by depressing the expression of meiosis regulators affecting the meiotic progression and also inhibited histone ubiquitination preventing the replacement of histones by protamines,by preventing RNF8 from entering nuclei,which affected the evolution of spermatids into mature sperm.

关键词： BDE-209 Meiosis L3MBTL2 Sperm RNF8 Histone ubiquitination

Sounding the alarm:Functionally referential signaling in Azure-winged Magpie

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Avian Research 2024年第1期15卷 35-41页

作者： Xingyi Jiang Yanyun Zhang Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China

Functionally referential signals are a complex form of communication that conveys information about the external *** signals have been found in a range of mammal and bird species and have helped us understand the complexities of animal *** are well known for their extraordinary cognitive abilities,but relatively little attention has been paid to their vocal ***,we investigated the functionally referential signals of a cooperatively breeding corvid species,Azure-winged Magpie(Cyanopica cyanus).Through field observations,we suggest that Azure-winged Magpie uses referential alarm calls to distinguish two types of threats:’rasp’ calls for terrestrial threats and ’chatter’ calls for aerial threats.A playback experiment revealed that Azure-winged Magpies responded to the two call types with qualitatively different *** sought cover by flying into the bushes in response to the ’chatter’ calls,and flew to or stayed at higher positions in response to ’rasp’ calls,displaying a shorter response time to ’chatter’ *** differences in acoustic structure were found between the two types of *** the extensive cognitive abilities of corvids and the fact that referential signals were once thought to be unique to primates,these findings are important for expanding our understanding of social communication and language evolution.

关键词： Alarm call Animal communication Azure-winged Magpie Referential signal

A novel structure of ultra-high-loading small moleculesencapsulated ZIF-8 colloid particles

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Nano Research 2024年第4期17卷 2929-2940页

作者： Pengfei Duan Yunhe An Xiaoxiao Wei Yanjie Tian Di Guan Xiangwen Liu Lanqun Mao Institute of Analysis and Testing Beijing Academy of Science and Technology(Beijing Center for Physical and Chemical Analysis)Beijing 100089China college of Chemistry Beijing Normal UniversityBeijing 100875China

The safety of nanoparticle-based drug delivery systems(DDSs)for cancer treatment is still a challenge,restricted by the intrinsic cytotoxicity of drug carriers and leakage of loaded ***,we propose a novel nanocarrier’s cytotoxicity avoidance strategy by synthesizing an encapsulation core–shell structure of zeolitic imidazolate framework-8(ZIF-8)-based colloid particles(CPs)with an amorphous ZIF-8 *** encapsulation structure achieves an ultra-high loading rate(LR)of 90%(i.e.,9 mg doxorubicin(DOX)per 1 mg ZIF-8)for DOX and the protection of DOX from ***,to deliver unit-dose drug,this ultra-high LR of 90%significantly reduces the usage of ZIF-8 to 1.2%(2 orders of magnitude)compared to that of DOX@ZIF-8 with a 10%LR,in which cytotoxicity of ZIF-8 could well below the safety limit and then be relatively ***,drug delivery efficacy,scale-up ability,and universality of this encapsulation structure have been further *** findings suggest the great potential of this ZIF-8-based encapsulation core–shell structure in the field of drug delivery.

关键词： metal-organic frameworks zeolitic imidazolate framework-8(ZIF-8) drug delivery nanoparticles nanostructures

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen Jian-Jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method