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The neutrophil–osteogenic cell axis promotes bone destruction in periodontitis
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作者 Yutaro Ando Masayuki Tsukasaki +12 位作者 Nam Cong-Nhat Huynh Shizao Zang Minglu Yan Ryunosuke Muro Kazutaka Nakamura Masatsugu Komagamine Noriko Komatsu Kazuo Okamoto Kenta Nakano Tadashi Okamura Akira Yamaguchi Kazuyuki Ishihara Hiroshi Takayanagi 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期154-162,共9页
The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction b... The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune–bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNAsequencing analysis on mouse periodontal lesions and showed that neutrophil–osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk. 展开更多
关键词 PERIOD NEUTROPHIL destruction
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Influence of vacuoles with gas–liquid inclusions on the thermobaric destruction conditions of natural quartz under dynamic heating in an RF-TICP torch system
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作者 苗龙 聂明卿 +7 位作者 Yuri Mihailovich GRISHIN 王晓宇 朱政羲 宋家辉 梁福文 何梓豪 田丰 王宁飞 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期138-147,共10页
In the present work,the turbulent mixing process of a polydisperse quartz particle flow with a plasma stream generated by a radio-frequency(RF)inductively coupled plasma torch was numerically studied.The thermobaric s... In the present work,the turbulent mixing process of a polydisperse quartz particle flow with a plasma stream generated by a radio-frequency(RF)inductively coupled plasma torch was numerically studied.The thermobaric stress in the quartz particles under dynamic heating in a heterogeneous plasma flow was determined by a two-stage approximation approach.The effect of the presence of vacuoles in natural quartz on the particle thermobaric destruction conditions was studied.It was found that the equivalent thermal and baric stresses in quartz particles may significantly increase in the presence of vacuoles within a small gas volume fraction.The influence of the regime and energetic working conditions of an RF inductively coupled plasma torch system on the particle thermobaric destruction conditions was examined,and a recommendation was given to promote the degree of thermobaric destruction of quartz particles,which is of substantial importance for improving the overall enrichment efficiency of quartz concentrates. 展开更多
关键词 high purity quartz dynamic heating vacuole with gas–liquid inclusions thermobaric destruction radio-frequency inductively coupled plasma torch
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Gold mineralization in Jiaodong Peninsula and destruction of North China Craton:Insights from Mesozoic granite
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作者 WANG Bin ZHOU Jianbo +8 位作者 DING Zhengjiang ZHAO Tiqun SONG Mingchun BAO Zhongyi LYU Junyang XU Shaohui YAN Chunming LIU Xiangdong LIU Jialiang 《Global Geology》 2023年第2期98-113,共16页
Large-scale tectonic magmatism and extensive gold mineralization have occurred in the eastern North China Craton(NCC)(Jiaodong and Liaodong peninsulas)since Mesozoic,which indicated that the region experienced decrato... Large-scale tectonic magmatism and extensive gold mineralization have occurred in the eastern North China Craton(NCC)(Jiaodong and Liaodong peninsulas)since Mesozoic,which indicated that the region experienced decratonization process.The genesis type of granites evolved from S-type to I-type and A-type during Late Jurassic to Early Cretaceous,and thus reflects the evolution of geodynamics in the Late Mesozoic,indicating the varied subduction process of the Paleo-Pacific Plate(PPP)and the craton destruction.The evolution of geochemical features shows that the mantle beneath the Jiaodong Peninsula evolved from EM-II in Jurassic to EM-I in Early Cretaceous,demonstrating that the mantle switched from enriched to depleted.The gold of decratonic gold deposits in Jiaodong Peninsula mainly comes from the lithospheric mantle domains metasomatized by fluids derived from the metamorphism and dehydration of the subducted slab in the mantle transition zone.The rapid decomposition of minerals leads to the concentrated release of ore-forming fluids,and this process leads to the explosive gold mineralization during the craton destruction.Extensive magmatic uplift and extensional structures,triggered by the craton destruction in Early Cretaceous formed the extensional tectonic system,providing space for the decratonic gold deposits in Jiaodong Peninsula. 展开更多
关键词 Jiaodong Peninsula Mesozoic granite craton destruction decratonic gold deposit extensional structure
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Modeling of organic pollutant destruction in a stirred tank reactor by ozonation 被引量:2
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作者 CHENG Jiang YANG Zhuo-ru +2 位作者 CHEN Huan-qin KUO C.H. ZAPPI E.M. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期449-452,共4页
Destruction of organic contaminants in water by ozonation is a gas liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require th... Destruction of organic contaminants in water by ozonation is a gas liquid process which involves ozone mass transfer and fast irreversible chemical reactions. Ozonation reactor design and process optimizing require the modeling of the gas liquid interactions within the reactor. In this paper a theoretical model combining the fluid dynamic and reaction kinetic parameters is proposed for predicting the destruction rates of organic pollutants in a semi batch stirred tank reactor by ozonation. A simple expression for the enhancement factor as our previous work has been applied to evaluate the chemical mass transfer coefficient in ozone absorption. 2,4 dichlorophenol (2,4 DCP) and 2,6 DCP or their mixture are chosen as the model compounds for simulating, and the predicted DCP concentrations are compared with some measured data. 展开更多
关键词 DICHLOROPHENOL destruction OZONATION stirred TANK REACTOR ENHANCEMENT factor
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Destruction of the Northern Margin of the North China Craton in Mid-Late Triassic: Evidence from Asthenosphere-derived Mafic Enclaves in the Jiefangyingzi Granitic Pluton from the Chifeng Area, Southern Inner Mongolia 被引量:2
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作者 LIU Jianfeng LI Jinyi +3 位作者 CHI Xiaoguo ZHENG Peixi HU Zhaochu ZHANG Xiaowei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第4期1071-1092,共22页
The petrology, geochronology and geochemistry of the mafic enclaves in the Mid-Late Triassic Jiefangyingzi pluton from Chifeng area, southern Inner Mongolia, in China are studied to reveal their petrogenetic relations... The petrology, geochronology and geochemistry of the mafic enclaves in the Mid-Late Triassic Jiefangyingzi pluton from Chifeng area, southern Inner Mongolia, in China are studied to reveal their petrogenetic relationship with the host pluton. Furthermore, the coeval magmatic assemblage and its petrogenesis on the northern margin of the North China craton(NCC) are studied synthetically to elucidate their tectonic setting and the implications for the destruction of the NCC. Zircon U-Pb dating reveals that the mafic enclaves formed at 230.4 ± 2.2 Ma, which is similar to the age of the host pluton. The most basic mafic enclaves belong to weak alkaline rocks, and they display rare earth element(REE) and trace element normalized patterns and trace element compositions similar to those of ocean island basalt(OIB). In addition, they have positive εNd(t) values(+3.84 to +4.94) similar to those of the Cenozoic basalts on the northern margin of the NCC. All of these geochemical characteristics suggest that the basic mafic rocks originated from the asthenosphere. Petrological and geochemical studies suggest that the Jiefangyingzi pluton and the intermediate mafic enclaves were formed by the mixing of the asthenosphere-derived and crust-derived magmas in different degrees. The Mid-Late Triassic magmatic rocks on the northern margin of the NCC could be classified into three assemblages according to their geochemical compositions: alkaline series, weak alkaline–sub-alkaline series and sub-alkaline series rocks. Petrogenetic analyses suggest that the upwelling of the asthenosphere played an important role in the formation of these Mid-Late Triassic magmatic rocks. Basing on an analysis of regional geological data, we suggest that the northern margin of the NCC underwent destruction due to the upwelling of the asthenosphere during the Mid-Late Triassic, which was induced by the delamination of the root of the collisional orogeny between Sino-Korean and Siberian paleoplates in Late Permian. 展开更多
关键词 mafic enclave craton destruction ASTHENOSPHERE Mid-Late Triassic North China craton
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Ultrasound-triggered microbubble destruction enhances the radiosensitivity of glioblastoma by inhibiting PGRMC1-mediated autophagy in vitro and in vivo 被引量:2
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作者 Ying He Xun-Hu Dong +3 位作者 Qiong Zhu Ya-Li Xu Ming-Liang Chen Zheng Liu 《Military Medical Research》 SCIE CSCD 2022年第3期331-350,共20页
Background:Ultrasound-triggered microbubble destruction(UTMD) is a widely used noninvasive technology in both military and civilian medicine,which could enhance radiosensitivity of various tumors.However,little inform... Background:Ultrasound-triggered microbubble destruction(UTMD) is a widely used noninvasive technology in both military and civilian medicine,which could enhance radiosensitivity of various tumors.However,little information is available regarding the effects of UTMD on radiotherapy for glioblastoma or the underlying mechanism.This study aimed to delineate the effect of UTMD on the radiosensitivity of glioblastoma and the potential involvement of autophagy.Methods:GL261,U251 cells and orthotopic glioblastoma-bearing mice were treated with ionizing radiation(IR) or IR plus UTMD.Autophagy was observed by confocal microscopy and transmission electron microscopy.Western blotting and immunofluorescence analysis were used to detect progesterone receptor membrane component 1(PGRMC1),light chain 3 beta 2(LC3B2) and sequestosome 1(SQSTM1/p62) levels.Lentiviral vectors or siRNAs transfection,and fluorescent probes staining were used to explore the underlying mechanism.Results:UTMD enhanced the radiosensitivity of glioblastoma in vitro and in vivo(P<0.01).UTMD inhibited autophagic flux by disrupting autophagosome-lysosome fusion without impairing lysosomal function or autophagosome synthesis in IR-treated glioblastoma cells.Suppression of autophagy by 3-methyladenine,bafilomycin A1 or ATG5 siRNA had no significant effect on UTMD-induced radiosensitization in glioblastoma cells(P<0.05).Similar results were found when autophagy was induced by rapamycin or ATG5 overexpression(P>0.05).Furthermore,UTMD inhibited PGRMC1expression and binding with LC3B2 in IR-exposed glioblastoma cells(P<0.01).PGRMC1 inhibitor AG-205 or PGRMC1siRNA pretreatment enhanced UTMD-induced LC3B2 and p62 accumulation in IR-exposed glioblastoma cells,thereby promoting UTMD-mediated radiosensitization(P<0.05).Moreover,PGRMC1 overexpression abolished UTMD-caused blockade of autophagic degradation,subsequently inhibiting UTMD-induced radiosensitization of glioblastoma cells.Finally,compared with IR plus UTMD group,PGRMC1 overexpression significantly increased tumor size [(3.8±1.1) mm^(2)vs.(8.0±1.9) mm^(2),P<0.05] and decreased survival time [(67.2±2.6) d vs.(40.0±1.2) d,P=0.0026] in glioblastoma-bearing mice.Conclusions:UTMD enhanced the radiosensitivity of glioblastoma partially by disrupting PGRMC1-mediated autophagy. 展开更多
关键词 Ultrasound-triggered microbubble destruction RADIOSENSITIZATION Progesterone receptor membrane component 1 AUTOPHAGY GLIOBLASTOMA
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Coordination and evolution mechanism of fractal crack network in mining rock mass destruction 被引量:1
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作者 YU Guang-ming~1, ZHANG Chun-hui~2 (1. Qingdao Institute of Architecture and Engineering, Qingdao 266033, China 2. Liaoning Technical University, Fuxin 123000, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期105-107,共3页
Based on the natural characters of stratum, complicated geological mining conditions and the essence of mining rock mass destruction, the complexity of rock mass destruction caused by miningw as analyzed. The inner li... Based on the natural characters of stratum, complicated geological mining conditions and the essence of mining rock mass destruction, the complexity of rock mass destruction caused by miningw as analyzed. The inner link between rock mass destruction phenomena caused by mining and nonlinear science was revealed. There are numerous cracks in natural rock mass. The cracks’ distribution is irregular and is of statistical fractal structure. Self-organizational nonlinear evolution of the inner structure flaws leads to the rock mass destruction with external force. The evolution includes single fault’s fractal development, formation and evolution of fractal crack network and coordination of fractal crack network, etc. The law of fractal crack network’s evolution was introduced, at the same time, the coordination of fractal crack network was analyzed. Finally, based on coordination the principal equation of mining-caused subsidence of structural rock mass was established and its steady-state solution and unsteady-state solution were found. 展开更多
关键词 the complexity of rock mass destruction FRACTAL CRACK NETWORK COORDINATION
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Antitumor effect of VEGFR2-targeted microbubble destruction with gemcitabine using an endoscopic ultrasound probe:In vivo mouse pancreatic ductal adenocarcinoma model 被引量:1
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作者 Nana Shimamoto Masaki Ito +3 位作者 Masafumi Chiba Sadamu Honma Hiroo Imazu Kazuki Sumiyama 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2020年第5期478-485,共8页
Background:Ultrasound-targeted microbubble destruction(UTMD)induces cellular inflow of drugs at low intensity,while high intensity eradicates tumor vessels.Since vascular endothelial growth factor receptor 2(VEGFR2)is... Background:Ultrasound-targeted microbubble destruction(UTMD)induces cellular inflow of drugs at low intensity,while high intensity eradicates tumor vessels.Since vascular endothelial growth factor receptor 2(VEGFR2)is highly expressed in pancreatic ductal adenocarcinoma(PDAC),VEGFR2-targeted microbubble(MB)might additionally increase the tissue specificity of drugs and thus improve antitumor effects.In addition,fixing the dual pulse intensity could maximize MB properties.This study evaluated the one-off(experiment 1)and cumulative(experiment 2)treatment effect of UTMD by regulating the dual pulse output applied to PDAC using VEGFR2-targeted MB.Methods:C57BL/6 mice inoculated with Pan-02 cells were allocated to five groups:VEGFR2-targeted MB+gemcitabine(GEM),VEGFR2-targeted MB,non-targeted MB+GEM,GEM,and control groups.After injection of GEM or GEM and either VEGFR2-targeted or non-targeted MB,UTMD was applied for several minutes at low intensity followed by high intensity application.In experiment 1,mice were treated by the protocol described above and then euthanized immediately or at the tumor diameter doubling time(TDT).In experiment 2,the same protocol was repeated weekly and mice were euthanized at TDT regardless of protocol completion.Histological analysis by CD31 and VEGFR2 staining provided microvascular density(MVD)and VEGFR2 expression along vessels(VEGFR2v)or intra/peripheral cells(VEGFR2c).Results:In experiment 1,TDT was significantly longer in the VEGFR2-targeted MB+GEM group compared to the non-targeted MB+GEM,GEM,and control groups,while the VEGFR2-targeted MB group showed no statistical significance.MVD and VEGFR2v in the immediate euthanasia was significantly lower in the VEGFR2-targeted MB+GEM and VEGFR2-targeted MB groups than other conditions.In experiment 2,the VEGFR2-targeted MB+GEM group produced significantly longer TDT than the GEM or control groups,whereas the VEGFR2-targeted MB group showed no significant difference.Histology revealed significantly reduced VEGFR2v and VEGFR2c in the VEGFR2-targeted and non-targeted MB+GEM groups,while only VEGFR2v was significantly less in the VEGFR2-targeted MB group.Conclusions:UTMD-mediated GEM therapy with the dual pulse application using VEGFR2-targeted MB substantially suppresses PDCA growth. 展开更多
关键词 Ultrasound-targeted microbubble destruction VEGFR2-targeted microbubble Pancreatic ductal adenocarcinoma GEMCITABINE
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Serum Metabonomics of Articular Cartilage Destruction Induced by T-2 Toxin in Wistar Rats 被引量:1
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作者 ZHU Lei ZHAO Zhi Jun +5 位作者 REN Xiao Bin LI Qiang DING Hua SUN Zhou KAO Qing Jun WANG Li Hua 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第1期76-80,共5页
T-2 导致毒素的软骨破坏的分子的致病还充分没被解开。这研究的目的是与关节的软骨破坏在一个老鼠异例模型在浆液代谢物检测变化。三十只健康男 Wistar 老鼠被喂包含 T-2 毒素(300 ng/kg 食物) 3 个月的一本食谱。在 femorotibial 软骨... T-2 导致毒素的软骨破坏的分子的致病还充分没被解开。这研究的目的是与关节的软骨破坏在一个老鼠异例模型在浆液代谢物检测变化。三十只健康男 Wistar 老鼠被喂包含 T-2 毒素(300 ng/kg 食物) 3 个月的一本食谱。在 femorotibial 软骨的组织病理学说的变化以 chondrocyte 退化 / 坏死和表面的软骨缺点被描绘,并且浆液的内长的代谢物侧面被 UPLC/Q-TOF MS 决定。对待的老鼠在关节的软骨显示出 chondrocyte 坏死和表面的软骨缺点的广泛的区域。另外, 8 代谢物被发现与控制组相比在这些老鼠显著地变化,包括 lysoPE ( 18:0/0:0 ), lysoPC ( 14:0 ), lysoPC [ 18:4 ( 6Z,9Z,12Z,15Z )], lysoPC [( 16:1 ( 9Z )], lysoPC ( 16:0 ),L缬氨酸, hippuric 酸,和 asparaginyl-glycine 。与损害主要是的软骨联系的这 8 代谢物在 phospholipid 和氨基酸包含了新陈代谢的小径。 展开更多
关键词 TOF MS Serum Metabonomics of Articular Cartilage destruction Induced by T-2 Toxin in Wistar Rats KBD
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Four-Octyl itaconate ameliorates periodontal destruction via Nrf2-dependent antioxidant system 被引量:3
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作者 Liangjing Xin Fuyuan Zhou +7 位作者 Chuangwei Zhang Wenjie Zhong Shihan Xu Xuan Jing Dong Wang Si Wang Tao Chen Jinlin Song 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期297-308,共12页
Periodontitis is a widespread oral disease characterized by continuous inflammation of the periodontal tissue and an irreversible alveolar bone loss, which eventually leads to tooth loss. Four-octyl itaconate(4-OI) is... Periodontitis is a widespread oral disease characterized by continuous inflammation of the periodontal tissue and an irreversible alveolar bone loss, which eventually leads to tooth loss. Four-octyl itaconate(4-OI) is a cell-permeable itaconate derivative and has been recognized as a promising therapeutic target for the treatment of inflammatory diseases. Here, we explored, for the first time,the protective effect of 4-OI on inhibiting periodontal destruction, ameliorating local inflammation, and the underlying mechanism in periodontitis. Here we showed that 4-OI treatment ameliorates inflammation induced by lipopolysaccharide in the periodontal microenvironment. 4-OI can also significantly alleviate inflammation and alveolar bone loss via Nrf2 activation as observed on samples from experimental periodontitis in the C57BL/6 mice. This was further confirmed as silencing Nrf2 blocked the antioxidant effect of 4-OI by downregulating the expression of downstream antioxidant enzymes. Additionally, molecular docking simulation indicated the possible mechanism under Nrf2 activation. Also, in Nrf2-/-mice, 4-OI treatment did not protect against alveolar bone dysfunction due to induced periodontitis, which underlined the importance of the Nrf2 in 4-OI mediated periodontitis treatment.Our results indicated that 4-OI attenuates inflammation and oxidative stress via disassociation of KEAP1-Nrf2 and activation of Nrf2 signaling cascade. Taken together, local administration of 4-OI offers clinical potential to inhibit periodontal destruction,ameliorate local inflammation for more predictable periodontitis. 展开更多
关键词 Four-Octyl itaconate ameliorates periodontal destruction via Nrf2-dependent antioxidant system
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Destruction of an advanced malignant tumour by direct electrical current-case report 被引量:1
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作者 Chima Oji John Ani 《Health》 2010年第9期1049-1053,共5页
We carried out a study on the effect of low-level direct current on cancer by using it to treat a woman who had a large malignant squamous cell carcinoma of the sinus cavity. We used a device that produced low-level d... We carried out a study on the effect of low-level direct current on cancer by using it to treat a woman who had a large malignant squamous cell carcinoma of the sinus cavity. We used a device that produced low-level direct current and passed the current through the tumour via a 4 × 4 cm flat aluminium foil and a needle electrode that was insulated along its entire length except for the portion actually inserted into the tumour. The treatment was eight hourly daily and lasted for eight weeks. The therapy resulted in the total remission of the tumour and a feeling of wellness by the patient. This finding implies promising therapeutic potential for the use of direct electrical current as a simple, effective, low cost alternative for the treatment of cancer. 展开更多
关键词 destruction MALIGNANT TUMOUR Human PATIENT DIRECT Electrical CURRENT
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Mud Wasps and Its Role in the Destruction of Ancient Buildings in Application to the Temple of Isis in the Temple of Dandara, Qena, Egypt and Methods of Prevention 被引量:1
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作者 Elashmawy Ahmed Abd-Elkareem Hany Ahmed Fouad 《Journal of Building Construction and Planning Research》 2022年第1期37-53,共17页
Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildin... Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildings, which represents a major challenge to these archaeological sites. It works to hide the stone surfaces and archaeological inscriptions found on them in addition to that it works to damage the stone surfaces themselves through the nests that they build on these surfaces. It works on weakening the structure of sandstone and the study that included a study on mud wasps and Analysis of nests and studied through the use of various devices and methods, the damage and its nature have also been studied as a result of the presence of wasp nests and the reasons for their existence. Various treatment methods and the best appropriate methods for treating sandstone and stopping wasp activity have also been studied. 展开更多
关键词 Mud Wasps SANDSTONE Temple of Isis destruction Treatment
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Destruction or Survival: Antithetical Characters in The Bluest Eye and Sula
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作者 韩小芳 《英语广场(学术研究)》 2012年第2期12-14,共3页
In Toni Morrison’s novel The Bluest Eye and Sula, there are two pairs of antithetical characters, one is Pecola and Claudia, the other is Sula and Nel. Due to the lack of redeeming intelligence, family emotional supp... In Toni Morrison’s novel The Bluest Eye and Sula, there are two pairs of antithetical characters, one is Pecola and Claudia, the other is Sula and Nel. Due to the lack of redeeming intelligence, family emotional support and community help, the protagonists Pecola and Sula gradually sink into destruction. In contrast, the less important characters Claudia and Nel manage to survive and gain some spiritual growth. 展开更多
关键词 Antithetical destruction SURVIVAL
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THE DESTRUCTION OF ANCIENT ECOLOGICAL ENVIRONMENT AND THE MOVEMENT OF CIVILIZATION CENTER IN CHINA
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作者 孔繁德 《Chinese Geographical Science》 SCIE CSCD 1992年第4期92-98,共7页
China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjian... China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjiang (Yangtze) River valley from the Huanghe (Yellow) River. This movement began in the Qin and Han dynasties (221 B.C-220 A.D.) because at that time the large-scale reclamation was felled, the grassland was reclaimed into farmland, the vegetation was seriously destroyed in the loess and north of the Huanghe River, and the climate was getting colder; and the turn from north to south occurred in the Sui and Tang dynasties (581-907 A.D.) and completed in the Song Dynasty (960-1279 A.D.). However, at present the vegetation damage of the Changjiang River valley is very serious too and the silt carrying capacity of the Changjiang River is increasing sharply; thus the Changjiang River is in danger of becoming a second Huanghe River, so we must pay attention to the protection of ecological 展开更多
关键词 blind RECLAMATION destruction of vegetation soil erosion DESERTIFICATION movement of CIVILIZATION CENTER
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STUDY ON WEAR AND DESTRUCTION OF HOB IN GEAR HOBBING
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作者 Liu Dawei Research Centre of Vehicle and Traffic Engineering, Qingdao University, Qingdao 266071, ChinaChen Jing Lu Shaofang Jilin University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第4期376-379,共4页
The wear and destruction appearances of hobs are researched. The reasons of the wear and destruction of hobare analyzed. And the influence of the change of the hobbing force and the hobbing temperature on the wear and... The wear and destruction appearances of hobs are researched. The reasons of the wear and destruction of hobare analyzed. And the influence of the change of the hobbing force and the hobbing temperature on the wear and destruc-tion of hob in gear hobbing is also analyzed. In gear hobbing, the main wear mechanisms are adhesion and ploughingwhen cutting the 20CrMnTi gear using W 18Cr4V high-speed steel hob. 展开更多
关键词 GEAR HOB GEAR HOBBING WEAR and destruction WEAR MECHANISM
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Dynamic heating and thermal destruction conditions of quartz particles in polydisperse plasma flow of RF-ICP torch system
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作者 L MIAO Yu M GRISHIN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第11期114-126,共13页
Numerical simulation of turbulent mixing process of polydisperse quartz particle(particle size distribution in the range of 0.1-0.4 mm)flow with Ar and Ar-H2 plasma generated by radio frequency inductively coupled pla... Numerical simulation of turbulent mixing process of polydisperse quartz particle(particle size distribution in the range of 0.1-0.4 mm)flow with Ar and Ar-H2 plasma generated by radio frequency inductively coupled plasma(RF-ICP)torch has been made.An approximate two-stage approach has been proposed to calculate the spatial-temporal distributions of temperature and resulting thermal stress in quartz particles during dynamic heating in polydisperse plasma flow.The influence of working gas compositions,particle size distributions,injection angle and flow rate of carrier gas on the thermal destruction conditions of quartz particles has been determined under different particle feed rates.It is found that all the solid quartz particles(0.1-0.4 mm)could be thermal destructed without overheating in RF-ICP torch system,when the hydrogen volume fraction in working gases is more than 1.5%-2%and particle feed rate is in a certain range.The values of the maximum and minimum feed rates have been determined under different hydrogen volume fractions.An optimal particle injection angle and flow rate of carrier gas is found around 50°-60°and 160-220 slpm,under which the value of maximum equivalent thermal stress in quartz particles is highest. 展开更多
关键词 RF-ICP torch dynamic heating thermal destruction hydrogen volume fraction optimal injection conditions
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Fibrous hamartoma of infancy with bone destruction of the tibia:A case report
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作者 Yong-Jie Qiao Wen-Bin Yang +5 位作者 Yan-Feng Chang Hao-Qiang Zhang Xin-Yuan Yu Sheng-Hu Zhou Yan-Yan Yang Lv-Dan Zhang 《World Journal of Clinical Cases》 SCIE 2022年第30期11190-11197,共8页
BACKGROUND Fibrous hamartoma of infancy(FHI)is a rare disease of infancy with unknown etiology.The disease mainly involves soft tissue,has no specific clinical manifestations,and is difficult to diagnose.At present,th... BACKGROUND Fibrous hamartoma of infancy(FHI)is a rare disease of infancy with unknown etiology.The disease mainly involves soft tissue,has no specific clinical manifestations,and is difficult to diagnose.At present,the diagnosis is mainly confirmed by histopathological examination,and the main treatment is surgical resection of the pathological tissue,which is prone to recurrence.CASE SUMMARY A five-month-old female patient was admitted to our hospital with swelling in the right calf.Two biopsies were performed in our hospital and another hospital,respectively,confirming the diagnosis as fibrous hamartoma.After exclusion of surgical contraindications,resection was performed with clear margins of 1 cm.Radiographic examination showed tumor recurrence more than four months after the operation,and surgery was performed again to extend the resection margins to 1.5 cm.The patient is recovering well,and after a follow-up of 36 mo,shows no signs of recurrence.CONCLUSION Our case report demonstrates that FHI should be considered in the differential diagnosis for a lower extremity mass with bone destruction.For FHI with bone destruction and unclear boundaries,excision margins of 1.5 cm could be superior to margins of 1 cm. 展开更多
关键词 INFANT TIBIA Fibrous hamartoma Bone destruction Case report
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The Ultrasonic NDT of Adherent Area between Metal and Nonmetal Surfaces and the Prediction of Its Destruction Strength
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作者 Lu Hongnian Han Yan Song ShuzhengNorth China Institute of Technology 《测试技术学报》 1994年第S1期213-213,共1页
A new approach so-called multi-reflection scanning method by transvers ultrason-ic wave is described for the NDT of adherend between metal and.nonmetal surfaces.Accord-ing to the adherent state,the destruction strengt... A new approach so-called multi-reflection scanning method by transvers ultrason-ic wave is described for the NDT of adherend between metal and.nonmetal surfaces.Accord-ing to the adherent state,the destruction strength can be predicted by Bayesian inference. A skew probe scanning on the metal side is used to transform the longitudinal wave,dis-patched by a PZT transducer,after entering the metal layer into transversal.Then the lat-ter propagates in a zigzag path along the adhesive layer.The reflected wave strength are de-tected and integrated with respect to time.The relation between the adherent area along thescanned path and the time integral of reflected wave magnitude is founded. The prediction model by Bayesian inference has been studied.As the adhesive process isfixed,the relation batween the destruction strength of a part versus the measured adherentarea proportion and their distribution can be established.Practice shows that,even the rateof spoilage as high as 60%,the software can strictly 展开更多
关键词 PREDICTION destruction adhesive ZIGZAG Bayesian inference founded longitudinal TRANSDUCER JUDGE
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Habitat destruction may lead to highly female-biased sex ratios
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作者 王亚强 《Journal of Chongqing University》 CAS 2017年第3期93-97,共5页
Local mate competition(LMC) was firstly used to explain extra-ordinary female-biased sex ratios. However, some observations have found that the sex ratios of some species are more female-biased than the predictions of... Local mate competition(LMC) was firstly used to explain extra-ordinary female-biased sex ratios. However, some observations have found that the sex ratios of some species are more female-biased than the predictions of LMC and its extensions; there is not yet a theory that accounts for the mechanisms of more female-biased sex ratio. Here, we assume that LMC occurs at a destructed habitat that reduces the resource for production, and present a new extension for the LMC model. Consequently, our model shows that the evolutionarily stable strategy(ESS) for sex ratio depends on two parameters: the number of foundresses and the degree of habitat destruction. Moreover, the sex ratio decreases as the degree of habitat destruction increases, i.e., the proportion of female increases. These results generally agree with experimental data, and may provide a new basis for the evolution of female-biased sex ratios in local mate competition and a new theory support for conservation of some species. 展开更多
关键词 local mate competition habitat destruction sex ratio evolutionarily stable strategy
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Emplacement Depths and Exhumation of Mesozoic Granitoids Responding to Lithospheric Destruction in the Jiaodong Peninsula, North China Craton
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作者 DOU Jingzhao ZHANG Huafeng CHEN Fukun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期76-77,共2页
1 Introduction The North China Craton(NCC)has experienced lithospheric destruction in Mesozoic accompanied with crustal exhumation.Fission track or(U-Th)/He dating of zircon and apatite for the Mesozoic granitoids in
关键词 Li Emplacement Depths and Exhumation of Mesozoic Granitoids Responding to Lithospheric destruction in the Jiaodong Peninsula NCC
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