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Low-dose testosterone treatment decreases oxidative damage in TM3 Leydig cells

Asian Journal of Andrology 2011年第3期13卷 432-437,512页

作者： Thomas IS Hwang Tien-Ling Liao Ji-Fan Lin Yi-Chia Lin shu-yu lee Yen-Chun Lai shu-Huei Kao Department of Urology Taipei Medical University Taipei Taiwan China Department of Urology School of Medicine Fu-Jen Catholic University Taipei Taiwan China Division of Urology Department of Surgery Shin Kong Wu Ho-Su Memorial Hospital Taipei Taiwan China School of Medical Laboratory Science and Biotechnology Taipei Medical University Taipei Taiwan China Central Laboratory Shin Kong Wu Ho-Su Memorial Hospital Taipei Taiwan China

Testosterone replacement therapy has benefits for aging men and those with hypogonadism. However, the effects of exogenous testosterone on Leydig cells are still unclear and need to be clarified. In this report, we demonstrate that testosterone supplementation can reduce oxidative damage in Leydig cells. The TM3 Leydig cell line was used as an in vitrocell model in this study. Cytoprotective effects were identified with 100-nmol l-1 testosterone treatment, but cytotoxic effects were found with ≥ 500-nmol l-1 testosterone supplementation. Significantly reduced reactive oxygen species （ROS） generation, lipid peroxide contents and hypoxia induction factor （HIF）-lα stabilization and activation were found with lO0-nmol 1-1 testosterone treatment. There was a 1.72-fold increase in ROS generation in the 500-nmol l-1 compared to the lO0-nmol l-1 testosterone treatment. A 1.58-fold increase in steroidogenic acute regulatory protein （STAR） expression was found in 50-nmol l-1 testosterone-treated cells （P〈0.01）. Chemically induced hypoxia was attenuated by testosterone supplementation. Leydig cells treated with low-dose testosterone supplementation showed cytoprotection by decreasing ROS and lipid peroxides, increasing StAR expression and relieving hypoxia stress as demonstrated by HIF-1α stabilization. Increased oxidative damage was found with ≥ 500-nmol l-1 testosterone manipulation. The mechanism governing the differential dose effects of testosterone on Leydig cells needs further investigation in order to shed light on testosterone replacement therapy.

关键词： Leydig cells oxidative damage reactive oxygen species testosterone

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Indian monsoon drove the dispersal of the thoracica group of Scytodes spitting spiders

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Zoological Research 2024年第1期45卷 152-159页

作者： yu-Fa Luo shu-Qiang Li School of Life and Environmental Sciences Shaoxing UniversityShaoxingZhejiang 312000China Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesYezinNay Pyi Taw 05282Myanmar

We examined the global biogeography of the Scytodes thoracica group of spitting spiders based on 23 years of sampling at the species level(61 species in the thoracica group and 84 species of Scytodes)using DNA data from six *** results indicated that the thoracica group initially dispersed from Southeast Asia to East Africa between 46.5 and 33.0 million years ago,and dispersal events intensified between Southeast/South Asia and East/South Africa from the early to late *** timing of these events indicates that Asian-African faunal exchange of the thoracica group was driven by the Indian monsoon,and the pattern of dispersal suggests that colonialization took root when the Indian monsoon shifted from a North-South direction to an East-West direction from the middle Eocene.

关键词： Geological event Climate change Ballooning organism Faunal exchange Species distribution

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Low-Brightness Object Recognition Based on Deep Learning

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Computers, Materials & Continua 2024年第5期79卷 1757-1773页

作者： shu-Yin Chiang Ting-yu Lin Department of Information and Telecommunications Engineering Ming Chuan UniversityTaoyuan City333Taiwan

This research focuses on addressing the challenges associated with image detection in low-light environments,particularly by applying artificial intelligence techniques to machine vision and object recognition *** primary goal is to tackle issues related to recognizing objects with low brightness *** this study,the Intel RealSense Lidar Camera L515 is used to simultaneously capture color information and 16-bit depth information *** detection scenarios are categorized into normal brightness and low brightness *** the system determines a normal brightness environment,normal brightness images are recognized using deep learning *** low-brightness situations,three methods are proposed for *** first method is the SegmentationwithDepth image(SD)methodwhich involves segmenting the depth image,creating amask from the segmented depth image,mapping the obtained mask onto the true color(RGB)image to obtain a backgroundreduced RGB image,and recognizing the segmented *** second method is theHDVmethod(hue,depth,value)which combines RGB images converted to HSV images(hue,saturation,value)with depth images D to form HDV images for *** third method is the HSD(hue,saturation,depth)method which similarly combines RGB images converted to HSV images with depth images D to form HSD images for *** experimental results,in normal brightness environments,the average recognition rate obtained using image recognition methods is 91%.For low-brightness environments,using the SD method with original images for training and segmented images for recognition achieves an average recognition rate of over 82%.TheHDVmethod achieves an average recognition rate of over 70%,while the HSD method achieves an average recognition rate of over 84%.The HSD method allows for a quick and convenient low-light object recognition *** research outcome can be applied to nighttime surveillance systems or nighttime road safety systems

关键词： Low-brightness depth image image segmentation image recognition HDV HSD

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Cu-substituted nickel hexacyanoferrate with tunable reaction potentials for superior ammonium ion storage

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Journal of Materials Science & Technology 2024年第2期169卷 19-27页

作者： Leiyu Fan Guangchang shu Yiwen Liu Haoxiang yu Lei Yan Liyuan Zhang Jie shu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China

In this work,a variety of Cu_(x)Ni_(2-x)Fe(CN)_(6)(x=0,0.4,0.8,1.2,1.6,2)cathodes for ammonium ion batteries are prepared and their electrochemical performances are *** the introduction of copper in nickel hexacyanoferrate,the electrochemical performance varies without changing the structure of nickel *** increase of Cu content in nickel hexacyanoferrate leads to the enhancement of reaction potential and *** results suggest that the substitution of Cu for Ni has a positive effect on improving the cycling stability and rate capacity of nickel hexacyanoferrate when x in Cu_(x)Ni_(2-x)Fe(CN)_(6)is less than ***,Cu_(0.4)Ni_(1.6)Fe(CN)_(6)exhibits the best cycling per-formance(capacity retention of 97.54%at 0.3 C)and the highest rate capacity(41.4 mAh g^(-1)at 10 C)in Cu_(x)Ni_(2-x)Fe(CN)_(6).Additionally,the X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)tests also reveal that the structural evolution of Cu_(0.4)Ni_(1.6)Fe(CN)_(6)is highly reversible upon NH_(4)^(+)***,this work proposes a candidate material for ammoniumion batteries and offers a novel avenue for adjusting the operating potential of the material.

关键词： Nickel hexacyanoferrate Copper hexacyanoferrate NH_(4)^(+)storage Ammonium ion batteries Aqueous batteries

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Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： Rui-Rui Liu Li-Bo Mao shu-Hong yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

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Pd-catalyzed intermolecular Si–O formation via Si–C activation

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Science China Chemistry 2024年第8期67卷 2661-2669页

作者： shuang Liu yu-shu Chen Yichen Wu Peng Wang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistryand Material Technology of Ministry of EducationHangzhou Normal UniversityHangzhou 311121China

The development of efficient Si–O bond formation reaction with 100% atom-economy, excellent functional group tolerance, and broad scope under mild conditions is highly desired due to the prevalence of silanol, silyl ether, and their derivatives in synthetic chemistry and materials science. Here, we have realized the Pd-catalyzed Si–O formation reaction via a Si–C activation approach with 100% atom-economy by employing silacyclobutanes(SCBs) and various hydroxy-containing substrates, including water,alcohols, phenols, and silanols. This protocol features a broad substrate scope, remarkable functional compatibility and mild conditions, providing a series of silanols, silyl ethers in high efficiency. Notably, this protocol could also be used for selective protection of hydroxy functionalities, and for the access of a class of novel polymers containing Si–O main chain. Preliminary mechanistic studies unveiled that this reaction underwent a Pd-catalyzed concerted ring-opening mechanism.

关键词： Si–O formation Si–C activation palladium silacyclobutane silanol silyl ether

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Comparison of models to predict air infiltration rate of buildings with different surrounding environments

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Building Simulation 2024年第6期17卷 1007-1021页

作者： shu Zheng Xiujiao Song Lin Duanmu yu Xue Xudong Yang Department of Building Science Tsinghua UniversityBeijing100084China School of Civil Engineering Dalian University of TechnologyDalian116024China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan030032China

The air infiltration rate of buildings strongly influences indoor environment and energy *** this study,several traditional methods for determining the air infiltration rate were compared,and their accuracy in different scenarios was ***,a method combining computational flow dynamics(CFD)with the Swami and Chandra(S-C)model was developed to predict the influence of the surrounding environment on the air infiltration *** buildings in Dalian,China,were selected:one with a simple surrounding environment and the other with a complex surrounding environment;their air infiltration rates were *** test results were used to validate the accuracy of the air infiltration rate solution models in different urban *** the building with a simple environment,the difference between the simulation and experimental results was 0.86%–22.52%.For the building with a complex environment,this difference ranged from 17.42%to 159.28%.We found that most traditional models provide accurate results for buildings with simple surrounding and that the simulation results widely vary for buildings with complex *** results of the method of combining CFD with the S-C model were more accurate,and the relative error between the simulation and test results was 10.61%.The results indicate that the environment around the building should be fully considered when calculating the air infiltration *** results of this study can guide the application of methods of determining air infiltration rate.

关键词： air infiltration rate models CFD simulation building surrounding air infiltration rate test

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Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen shu-lin Lü Di-jia Zhao Wei Guo Jian-yu Li shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

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Autonomous navigation of an asteroid orbiter enhanced by a beacon satellite in a high-altitude orbit

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Astrodynamics 2024年第3期8卷 375-400页

作者： Weidong Yin yu Shi Leizheng shu Yang Gao University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China

This study aims to assess the autonomous navigation performance of an asteroid orbiter enhanced using an inter-satellite link to a beacon *** navigation includes the orbit determination of the orbiter and beacon,and asteroid gravity estimation without any ground station *** measurements were acquired using satellite-to-satellite tracking(SST)and optical observation of asteroid surface *** study presents a new orbiter-beacon SST scheme,in which the orbiter circumnavigates the asteroid in a low-altitude strongly-perturbed orbit,and the beacon remains in a high-altitude weakly-perturbed *** used Asteroid 433 Eros as an example,and analyzed and designed low-and high-altitude orbits for the orbiter and *** navigation measurements were precisely modeled,extended Kalman filters were devised,and observation configuration was analyzed using the Cramer-Rao lower bound(CRLB).Monte Carlo simulations were carried out to assess the effects of the orbital inclination and altitudes of the orbiter and beacon as key influencing *** simulation results showed that the proposed SST scheme was an effective solution for enhancing the autonomous navigation performance of the orbiter,particularly for improving the accuracy of gravity estimation.

关键词： asteroid exploration gravity estimation orbit determination satellite-to-satellite tracking(SST) optical observation

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Machine Learning-based Identification of Contaminated Images in Light Curve Data Preprocessing

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Research in Astronomy and Astrophysics 2024年第4期24卷 287-295页

作者： Hui Li Rong-Wang Li Peng shu yu-Qiang Li yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Space Object and Debris Observation Chinese Academy of SciencesNanjing 210023China

Attitude is one of the crucial parameters for space objects and plays a vital role in collision prediction and debris *** light curves to determine attitude is the most commonly used *** photometric observations,outliers may exist in the obtained light curves due to various ***,preprocessing is required to remove these outliers to obtain high quality light *** statistical analysis,the reasons leading to outliers can be categorized into two main types:first,the brightness of the object significantly increases due to the passage of a star nearby,referred to as“stellar contamination,”and second,the brightness markedly decreases due to cloudy cover,referred to as“cloudy contamination.”The traditional approach of manually inspecting images for contamination is time-consuming and ***,we propose the utilization of machine learning methods as a *** Neural Networks and SVMs are employed to identify cases of stellar contamination and cloudy contamination,achieving F1 scores of 1.00 and 0.98 on a test set,*** also explore other machine learning methods such as ResNet-18 and Light Gradient Boosting Machine,then conduct comparative analyses of the results.

关键词： techniques:image processing methods:data analysis light pollution

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