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Rhodamine Mechanophore Functionalized Mechanochromic Double Network Hydrogels with High Sensitivity to Stress

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Chinese Journal of Polymer Science 2020年第1期38卷 24-36,I0005页

作者： Li-jun Wang Kai-Xiang Yang Qiang Zhou Hai-Yang Yang Jia-Qing He Xing-yuan Zhang School of Chemistry and Materials Science University of Science and Technology of China

Mechanochromic hydrogels, a new class of stimuli-responsive soft materials, have potential applications in a number of fields such as damage reporting and stress/strain sensing. We prepared a novel mechanochromic hydrogel using a strategy that has been developed to prepare dual-network(DN) hydrogels. A hydrophobic rhodamine derivative(Rh mechanophore) was covalently incorporated into a first network as a cross-linker. This first network embedded with Rh mechanophore within the DN hydrogel was pre-stretched. This guaranteed that the stress could be transferred extensively to the Rh-crosslinked first network once the hydrogel was under an applied force. Interestingly, we found that the threshold stress required to activate the mechanochromism of the hydrogel was less than 200 kPa, and much less than those in previous reports. Moreover, because of the excellent sensitivity of the hydrogel to stress, the DN hydrogel exhibited reversible freezing-induced mechanochromism. Benefiting from the sensitivity of Rh mechanophore to both p H and force, the DN hydrogel showed p H-regulated mechanochromic behavior. Our experimental results indicate that the preparation strategy we used introduces sensitive mechanochromism into the hydrogel and preserves the advantageous mechanical properties of the DN hydrogel. These results will be beneficial to the design and preparation of mechanochromic hydrogels with high stress sensitivity, and foster their practical applications in a number of fields such as damage reporting and stress/strain sensing.

关键词： Rhodamine mechanophore Mechanochromic Dual-network hydrogel Freezing-induced mechanochromism pH-regulated Stress sensitivity

Successful individualized endodontic treatment of severely curved root canals in a mandibular second molar:A case report

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World Journal of Clinical Cases 2022年第14期10卷 4632-4639页

作者： Lai-jun Xu Jian-Ying Zhang Zi-hua huang Xiang-Zhu Wang Hunan Key Laboratory of Oral Health Research Hunan 3D Printing Engineering Research Center of Oral CareHunan Clinical Research Center of Oral Major Diseases and Oral HealthAcademician Workstation for Oral-maxilofacial and Regenerative Medicine and Xiangya Stomatological HospitalXiangya School of StomatologyCentral South UniversityChangsha 410008Hunan ProvinceChina

BACKGROUND The incidence rate of severely curved root canals in mandibular molars is low,and the root canal treatment of mandibular molars with this aberrant canal anatomy may be technically *** SUMMARY A 26-year-old Chinese female patient presented with intermittent and occlusal pain in the left mandibular second *** patient had undergone filling restoration for caries before endodontic *** the aid of cone beam computed tomography(CBCT),a large periapical radiolucency was observed,and curved root canals in a mandibular second molar were confirmed,depicting a severe and curved distolingual *** treatments,including novel individualized preparation skills and techniques and the use of bioceramic materials as an apical barrier,were performed,and complete healing of the periapical lesion and a satisfactory effect were *** A case of severely curved root canals in a mandibular second molar was successfully treated and are reported *** complex anatomy of the tooth and the postoperative effect were also evaluated via the three-dimensional reconstruction of CBCT images,which accurately identified the aberrant canal *** devices and biomaterial applications combined with novel synthesis techniques can increase the success rate of intractable endodontic treatment.

关键词： Cone beam computed tomography Canal curvature Mandibular second molar Root canal therapy Case report

Observing the evolution of graphene layers at high current density

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Nano Research 2016年第12期9卷 3663-3670页

作者： Chun-Wei huang Jui-yuan Chen Chung-hua Chiu Cheng-Lun Hsin Tseung-Yuen Tseng Wen-Wei Wu Department of Materials Science and Engineering Chiao Tung University 1001 University Road Hsinchiu 30010 Taiwan China Department of Electrical Engineering Central University Chung-Li City Taoyuan 32001 Taiwan China Department of Electronics Engineering and Institute of Electronics Chiao Tung University 1001 University Road Hsinchiu 30010 Taiwan China

Graphene has demonstrated its potential in several practical applications owing to its remarkable electronic and physical properties. In this study, we successfully fabricated a suspended graphene device with a width down to 20 nm. The morphological evolution of graphene under various electric field effects was systematically examined using an in-situ transmission electron microscope （TEM）. The hourglass-shaped graphene sample instantly broke apart at 7.5 mA, indicating an impressive breakdown current density. The current-carrying capacity was calculated to be -1.6 × 10^9 ***-2, which is several orders higher than that of copper. The current-carrying capacity depended on the resistivity of graphene. In addition, atomic volume changes occurred in the multilayer graphene samples due to surface diffusion and Ostwald ripening （OR）, indicating that the breakdown mechanism is well approximated by the electric field. This study not only provides a theory to explain the breakdown behavior but also presents the effects on materials contacted with a graphene layer used as the transmission path.

关键词： graphene breakdown high current density in-situ transmissionelectron microscope (TEM) Ostwald ripening

Competency-based management effects on satisfaction of nurses and patients

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International Journal of Nursing Sciences 2014年第1期1卷 121-125页

作者： Zong-Xia Chang Gui-hua Yang Wei yuan Nursing Department People’s Hospital of Liaocheng CityLiaochengChina

Purpose:To evaluate the effect of competency-based management in improving nurse and patient ***:According to the competency-based management objectives and principles,821 nurses were classified into different levels based on clear nurse qualifications and post *** to the different levels of nursing staff and training plans with different emphases,the goal was for the nursing staff to gradually achieve the corresponding *** training programs for different levels of nurses were formulated to enable nurses to gradually increase their competency ***:After implementation of competency-based management,nurse job satisfaction and patient satisfaction increased significantly(P<0.01).Additionally,the reported nurse job burnout decreased(P<0.01).Conclusion:Competency-based management can promote nurses’enthusiasm,reduce job burnout,improve job satisfaction,as well as improve patient satisfaction.

关键词： Competency-based management Nurses Patient satisfaction

High-performance martensitic stainless steel nanocomposite powder for direct energy deposition prepared by ball milling

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Rare Metals 2023年第7期42卷 2419-2432页

作者： Zhen Wang Shu-Rong Xu Qing-Xuan Sui Jiang Wang Bo Liu Hao Wen Tian-Yi Xiao Quan yuan Feng-jun Zhao jun Liu School of Materials Science and Engineering Central South UniversityChangsha410083China Jinchuan Nickel Cobalt Research and Design Institute Jinchuan Group Co.LtdJinchang737100China

Direct energy deposition(DED)has great potential for the production of stainless steel matrix nanocomposite ***,the propensity of nanoparticle agglomeration leads to the difficulty in realizing homogenous dispersion of nanoparticles in the *** this study,a series of agglomeration-free nanoWC-Co-reinforced 420 stainless steel matrix nanocomposite powders with high flowability were prepared by ball milling under the optimal *** effect of ball milling time on the properties of the composite powders was *** powder properties ensure the DED processing ***,the corresponding composites were fabricated by DED,and the effects of nano-WC-Co content on the properties of the composites were comprehensively *** contact angles between the single pass cladding layer and the substrate change with increasing nano-WC-Co content(decrease from 127.38°to 113.07°).The different contact angles will significantly influence the quality of the multipass cladding ***,the addition of nanoWC-Co leads not only to further grain refinement but also to more pronounced isotropy of the micros *** the increase in nano-WC-Co content,the corrosion resistance is significantly improved(62.28%lower corrosion current for 420-15 wt%nano-WC-Co than for 420).

关键词： Steel matrix composites Direct energy deposition(DED) Ball milling time Contact angle Microstructure Mechanical property

Climate change attribution of the 2021 Henan extreme precipitation: Impacts of convective organization

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Science China Earth Sciences 2022年第10期65卷 1837-1846页

作者： Han QIN Wei yuan jun WANG Yang CHEN Panxi DAI Adam HSOBEL Zhiyong MENG Ji NIE Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China Aviation Meteorological Center Civil Aviation Administration of ChinaBeijing 100621China Key Laboratory of Regional Climate-Environment for Temperate East Asia(RCE-TEA) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric Science School of Earth SciencesZhejiang UniversityHangzhou 310027China Department of Applied Physics and Applied Mathematics and Lamont-Doherty Earth Observatory Columbia University

In this study, we investigate the climate attribution of the 21·7 Henan extreme precipitation event. A conditional storyline attribution method is used, based on simulations of the event with a small-domain high-resolution cloud-resolving model. Large-scale vertical motion is determined by an interactive representation of large-scale dynamics based on the quasigeostrophic omega equation, with dynamical forcing terms taken from observation-based reanalysis data. It is found that warming may lead to significant intensification of both regional-scale(10–14% K, depending on convective organization) and station-scale precipitation extremes(7–9% K^(-1)). By comparing clustered convection organized by a localized surface temperature anomaly and squall-line convection organized by vertical wind shear, we further explored how convective organization may modify precipitation extremes and their responses to warming. It is found that shear convective organization is much more sensitive to large-scale dynamic forcing and results in much higher precipitation extremes at both regional and station scales than unorganized convection is. The clustered convection increases station-scale precipitation only slightly during heavy precipitation events. For regional-scale extreme precipitation sensitivity, shear-organized convection has a larger sensitivity by 2–3% Kthan that of unorganized convection, over a wide temperature range, due to its stronger diabatic heating feedback. For the station-scale extreme precipitation sensitivity, no systemic dependence on convective organization is found in our simulations.

关键词： Extreme precipitation Global warming Climate change attribution Convective organization Hourly precipitation

Effects of thermal treatment on physical and mechanical characteristics of coal rock

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Journal of Central South University 2016年第9期23卷 2336-2345页

作者： YIN Tu-bing WANG Pin LI Xi-bing SHU Rong-hua YE Zhou-yuan School of Resources and Safety Engineering Central South University Changsha 410083 China School of Energy and Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

To study the physical and mechanical properties of coal rock after treatment at different temperatures under impact loading, dynamic compression experiments were conducted by using a split Hopkinson pressure bar(SHPB). The stress–strain curves of specimens under impact loading were obtained, and then four indexes affected by temperature were analyzed in the experiment: the longitudinal wave velocity, elastic modulus, peak stress and peak strain. Among these indexes, the elastic modulus was utilized to express the specimens' damage characteristics. The results show that the stress–strain curves under impact loading lack the stage of micro-fissure closure and the slope of the elastic deformation stage is higher than that under static loading. Due to the dynamic loading effect, the peak stress increases while peak strain decreases. The dynamic mechanical properties of coal rock show obvious temperature effects. The longitudinal wave velocity, elastic modulus and peak stress all decrease to different extents with increasing temperature, while the peak strain increases continuously. During the whole heating process, the thermal damage value continues to increase linearly, which indicates that the internal structure of coal rock is gradually damaged by high temperature.

关键词： rock mechanical property split Hopkinson pressure bar (SHPB) high temperature coal rock dynamic mechanical property

Intestinal Protozoan Infections in Patients with Diarrhea—Shanghai Municipality,Zhenjiang City,and Danyang City,China,2011–2015 and 2019–2021

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China CDC weekly 2022年第8期4卷 143-147页

作者： Yanyan Jiang Zhongying yuan hua Liu Jianhai Yin yuan Qin Xiaofeng Jiang Jie Xu Jianping Cao Yujuan Shen National Institute of Parasitic Diseases Chinese Center for Disease Control and Prevention(Chinese Center for Tropical Diseases Research)Key Laboratory of Parasite and Vector BiologyNational Health Commission of the People’s Republic of ChinaWorld Health Organization Collaborating Centre for Tropical DiseasesShanghaiChina School of Global Health Chinese Center for Tropical Diseases ResearchShanghai Jiao Tong University School of MedicineShanghaiChina

Summary What is already known about this topic?Intestinal protozoa are common pathogens of diarrhea ***,the etiology of diarrhea due to intestinal protozoan infections in China is not *** is added by this report?Based on active syndromic surveillance in Shanghai,Zhenjiang,and Danyang during 2011–2015 and 2019–2021,89(1.67%)patients were infected with intestinal protozoa(Cryptosporidium spp.,Giardia duodenalis,Enterocytozoon bieneusi,and Cyclospora cayetanensis),and positivity rates statistically differed by region and *** are the implications for public health practice?This was the most comprehensive data collection in investigating parasitic diarrheal diseases in *** of these protozoa in diarrhea will provide new perspectives for detecting hidden etiological agents of diarrhea as early as possible.

关键词： globally ang detecting

Incremental Multi-Label Learning with Active Queries

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Journal of Computer Science & Technology 2020年第2期35卷 234-246页

作者： Sheng-jun huang Guo-Xiang Li Wen-Yu huang Shao-yuan Li College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Pattern Analysis and Machine Intelligence Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing University Nanjing 210023China

In multi-label learning,it is rather expensive to label instances since they are simultaneously associated with multiple ***,active learning,which reduces the labeling cost by actively querying the labels of the most valuable data,becomes particularly important for multi-label learning.A good multi-label active learning algorithm usually consists of two crucial elements:a reasonable criterion to evaluate the gain of querying the label for an instance,and an effective classification model,based on whose prediction the criterion can be accurately *** this paper,we first introduce an effective multi-label classification model by combining label ranking with threshold learning,which is incrementally trained to avoid retraining from scratch after every *** on this model,we then propose to exploit both uncertainty and diversity in the instance space as well as the label space,and actively query the instance-label pairs which can improve the classification model *** experiments on 20 datasets demonstrate the superiority of the proposed approach to state-of-the-art methods.

关键词： active learning multi-label learning uncertainty diversity