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Synthesis of boron nitride nanorod and its performance as a metalfree catalyst for oxidative desulfurization of diesel fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 120-132页

作者： Tanaz Ghanadi Gholamreza Moradi Alimorad Rashidi Catalyst research center Faculty of Chemical and Petroleum EngineeringRazi UniversityKermanshahIran Nanotechnology research center Research Institute of Petroleum Industry(RIPI)TehranIran

In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal efree catalyst in the present research.This nanocatalyst was synthesized via template-free approach followed by heating treatment at 900℃in nitrogen atmosphere that the characteristics of the sample were identified by the X-ray diffraction,Fourier-transform infrared spectroscopy,Raman spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,atomic force microscopy,and N2 adsorptionedesorption isotherms.The results of structural and morphological analysis represented that BN has been successfully synthesized.The efficacy of the main operating parameters on the process was studied by using response surface methodology based on the BoxeBehnken design method.The prepared catalyst showed high efficiency in oxidative desulfurization of diesel fuel with initial sulfur content of 8040 mg·kg^(-1)S.From statistical analysis,a significant quadratic model was obtained to predict the sulfur removal as a function of efficient parameters.The maximum efficiency of 72.4%was achieved under optimized conditions at oxidant/sulfur molar ratio of 10.2,temperature of 71℃,reaction time of 113 min,and catalyst dosage of 0.36 g.Also,the reusability of the BN was studied,and the result showed little reduction in activity of the catalyst after 10 times regeneration.Moreover,a plausible mechanism was proposed for oxidation of sulfur compounds on the surface of the catalyst.The present study shows that BN materials can be selected as promising metal-free catalysts for desulfurization process.

关键词： Desulfurization Boron nitride(BN)nanostructure Experimental design BoxeBehnken

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： Cheng Zheng Li Yang Yunbing Wang National Engineering research center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been recognized as golden standard for the treatment of VHD.Owing to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of VHD.However,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune response.To prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of SVD.In this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

On-surface synthesis and characterization of polyynic carbon chains

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National Science Review 2024年第3期11卷 192-199页

作者： Wenze Gao Wei Zheng Luye Sun Faming Kang Zheng Zhou Wei Xu Interdisciplinary Materials research center School of Materials Science and Engineering Tongji University

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au（111） surface;the longest one observed consists of ～60 alkyne units（120 carbon atoms）. The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule(C14Cl10) on a bilayer NaCl/Au（111） surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy,in a good agreement with the theoretical HOMO–LUMO gap（5.48 eV）.

关键词： polyyne scanning probe microscopy carbon allotrope on-surface synthesis organometallic polyyne

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel research center Research Institute of Highway Ministry of TransportBejing 100088China Tunnel and Underground Engineering research center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Chromosome-level genome assembly of the Asian citrus psyllid,Diaphorina citri

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Insect Science 2024年第1期31卷 13-27页

作者： Shuang Lei Shi-Jiang Yu Qi Pan Li-Li Ding Si-Chen Li Lu-Yan Cheng Shu-Qi Wang Bing-Hai Lou Jun He Cui-Yun Lei Lin Cong Hao-Qiang Liu Xue-Feng Wang Chun Ran Citrus research Institute Southwest University/Chinese Academy of Agricultural SciencesNational Engineering Research Center for CitrusChongqingChina

Diaphorina citri is a global citrus pest.As a vector insect,it can transmit the causative agents of citrus huanglongbing,causing irreversible losses to the citrus industry.The acquisition of genomic information can provide a molecular genetic basis for effective control of D.citri.Here,the DNBSEQ™,Oxford Nanopore Technologies,and Hi-C technologies are applied to generate a high-quality chromosome-level genome of D.citri.The genome size of D.citri was 523.78 Mb with a scaffold N50 of 47.05 Mb distributed on 13 chromosomes.A total of 250.64 Mb(47.85%)repeat sequences and 24048 protein-coding genes were predicted.Genome resequencing of female and male individuals indicated that the sex chromosome system of D.citri is XO.Phylogenetic analysis demonstrated that D.citri and Pachypsylla venusta,which separated from their most recent common ancestor about 336.62 million years ago,were the most closely related.Additionally,we identified genes potentially involved in detoxification metabolism,pathogen transmission,and honeydew secretion for further investigation.The high-quality genome provides an important reference for developing effective management strategies of D.citri.

关键词： Asian citrus psyllid chromosome-level genome comparative genomics cytochrome P450 detoxification Huanglongbing

Association between body mass index and in vitro fertilization/intra-cytoplasmic sperm injection outcomes: An analysis of 15,124 normal ovarian responders in China

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中华医学杂志(英文版) 2024年第7期137卷 837-845页

作者： Zheng Danlei Wang Yuanyuan Chen Lixue Zeng Lin Li Rong Department of Obstetrics and Gynecology center for Reproductive Medicine Peking University Third Hospital Beijing 100191 China research center of Clinical Epidemiology

Background: High body mass index (BMI) results in decreased fecundity, and women with high BMI have reduced rates of clinical pregnancy and live birth inin vitro fertilization/intra-cytoplasmic sperm injection (IVF/ICSI). Meanwhile, ovarian responses show great heterogeneity in patients with a high BMI. This study aimed to analyze the effects of a high BMI on IVF/ICSI outcomes in the Chinese female with normal ovarian response.Methods: We performed a retrospective cohort study comprising 15,124 patients from the medical record system of the Reproductive center of Peking University Third Hospital, with 3530 (23.3%) in the overweight group and 1380 (9.1%) in the obese group, who had a normal ovarian response (5-15 oocytes retrieved) and underwent fresh embryo transfer (ET) cycles from January 2017 to December 2018, followed by linked frozen-thawed embryo transfer (FET) cycles from January 2017 to December 2020. Cumulative live birth rate (CLBR) was used as the primary outcome. Furthermore, a generalized additive model was applied to visually illustrate the curvilinear relationship between BMI and the outcomes. We used a decision tree to identify the specific population where high BMI had the greatest effect on IVF/ICSI outcomes.Results: High BMI was associated with poor IVF/ICSI outcomes, both in cumulative cycles and in separate fresh ET or FET cycles. In cumulative cycles, compared with the normal weight group, obesity was correlated with a lower positive pregnancy test rate (adjusted odds ratio [aOR]: 0.809, 95% confidence interval [CI]: 0.682-0.960), lower clinical pregnancy rate (aOR: 0.766, 95% CI: 0.646-0.907), lower live birth rate (aOR: 0.706, 95% CI: 0.595-0.838), higher cesarean section rate (aOR: 2.066, 95% CI: 1.533-2.785), and higher rate of large for gestational age (aOR: 2.273, 95% CI: 1.547-3.341). In the generalized additive model, we found that CLBR declined with increasing BMI, with 24 kg/m2 as an inflection point. In the decision tree, BMI only made a difference in the population aged ≤34.5 yea

关键词： Obesity Body mass index In vitro fertilization Live birth Decision trees Normal ovarian response

Design of Resilient Sensor Networks Balancing Resilience and Efficiency

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International Journal of Disaster Risk Science 2024年第1期15卷 107-115页

作者： Sergey N.Vecherin Kiril D.Ratmanski Luke Hogewood Igor Linkov Cold Regions research and Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been developed and applied in many technical areas,becoming exceptionally pertinent to disaster risk science.During a disaster situation,accurate sensing information is the key to efficient recovery efforts.In general,resilience aims to minimize the impact of disruptions to systems through the fast recovery of critical functionality,but resilient design may require redundancy and could increase costs.In this article,we describe a method based on binary linear programming for sensor network design balancing efficiency with resilience.The application of the developed framework is demonstrated for the case of interior building surveillance utilizing infrared sensors in both twoand three-dimensional spaces.The method provides optimal sensor placement,taking into account critical functionality and a desired level of resilience and considering sensor type and availability.The problem formulation,resilience requirements,and application of the optimization algorithm are described in detail.Analysis of sensor locations with and without resilience requirements shows that resilient configuration requires redundancy in number of sensors and their intelligent placement.Both tasks are successfully solved by the described method,which can be applied to strengthen the resilience of sensor networks by design.The proposed methodology is suitable for large-scale optimization problems with many sensors and extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Redundant networks Resilience and efciency Resilient sensor networks

Intranasal boosting with RBD-HR protein vaccine elicits robust mucosal and systemic immune responses

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Genes & Diseases 2024年第4期11卷 327-339页

作者： Li Chen Wenyan Ren Hong Lei Jiayu Wang Haiying Que Dandan Wan Aqu Alu Dandan Peng Minyang Fu Weiqi Hong Yuhe Huang Xiangrong Song Guangwen Lu Xiawei Wei Laboratory of Aging research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuan 610041China

The emergence of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants has decreased the efficacy of SARs-CoV-2 vaccines in containing coronavirus disease 2019(CoVID-19)over time,and booster vaccination strategies are urgently necessitated to achieve sufficient protection.Intranasal immunization can improvemucosal immunity,offer-ing protection against the infection and sustaining the spread of SARS-CoV-2.In this study,an intranasal booster of the RBD-HR vaccine after two doses of the mRNA vaccine significantly increased the levels of specific binding antibodies in serum,nasal lavage fluid,and bronchoal-veolar lavage fluid compared with only two doses of mRNA vaccine.After intranasal boosting with the RBD-HR vaccine,the levels of serum neutralizing antibodies against prototype and variant strains of SARS-Cov-2 pseudoviruses weremarkedly higher than those in mice receiving mRNA vaccine alone,and intranasal boosting with the RBD-HR vaccine also inhibited the bind-ing of RBD to hACE2 receptors.Furthermore,the heterologous intranasal immunization regimen promoted extensive memory T cell responses and activated CD103+dendritic cells in the respiratory mucosa,and potently enhanced the formation of T follicular helper cells and germinal center B cells in vital immune organs,including mediastinal lymph nodes,inguinal lymph nodes,and spleen.Collectively,these data infer that heterologous intranasal boosting with the RBD-HR vaccine elicited broad protective immunity against SARS-CoV-2 both locallyandsystemically.

关键词： Heterologous immunization Intranasal immunization mRNA vaccine SARS-CoV-2 Subunitprotein vaccine

Relationship between mitochondrial respiratory dysfunction of blood mononuclear cells and heart failure severity

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Journal of Geriatric Cardiology 2024年第1期21卷 130-134页

作者： Viacheslav A.Korepanov Tariel A.Atabekov Tatiana Yu.Rebrova Roman E.Batalov Sergey A.Afanasiev Cardiology research Institute Tomsk National Research Medical CenterRussian Academy of SciencesTomskRussia

Chronic heart failure(CHF)is a clinical syndrome manifested by reduced pumping ability of the heart,increased pressure in heart chambers in both physical activity and at rest.The symptoms of this syndrome are dyspnea,undue fatigability,peripheral edema,which follow structural and functional changes of the myocardium.[1]The growing incidence of CHF,especially among elderly people,is an urgent problem for medicine in the vast majority of industrialized countries.For instance,in Russian Federation,CHF is diagnosed in about 7%of cardiovascular patients.At the same time,this indicator varies from 0.3%in young people(20-29 years old)to 70%in the older age group.[2,3].

关键词： severity instance pumping