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Spatiotemporal Evolution of Ecological Quality in Typical Karst Ecologically Fragile Areas Based on Remote Sensing Ecological Indexes
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作者 Denghong HUANG Zhiying ZHANG Zhenzhen ZHANG 《Meteorological and Environmental Research》 2024年第2期22-28,共7页
Fast and effective remote sensing monitoring is an important means for analyzing the spatio-temporal changes in ecological quality in fragile karst regions.This study focuses on Guanling Autonomous County,a national-l... Fast and effective remote sensing monitoring is an important means for analyzing the spatio-temporal changes in ecological quality in fragile karst regions.This study focuses on Guanling Autonomous County,a national-level demonstration county for comprehensive desertification control.Based on Landsat TM/OLI remote sensing image data from 2005,2010,2015,and 2020,remote sensing ecological indices were used to analyze the spatio-temporal changes in ecological quality in Guanling Autonomous County from 2005 to 2020.The results show that:①the variance contribution rates of the first principal component for the four periods were 66.31%,71.59%,63.18%,and 75.24%,indicating that PC1 integrated most of the characteristics of the four indices,making the RSEI suitable for evaluating ecological quality in karst mountain areas;②the remote sensing ecological index grades have been increasing year by year,with an overall trend of improving ecological quality.The area of higher-grade ecological quality has increased spatially,while fragmented patches have gradually decreased,becoming more concentrated in the low-altitude areas in the northwest and east,and there is a trend of expansion towards higher-altitude areas;③the ecological environment quality in most areas has improved,with the improvement in RSEI spatio-temporal variation becoming more noticeable with increasing slope.Areas of higher-grade quality appeared in 2010,and the range of higher-grade quality expanded with increasing slope. 展开更多
关键词 Ecological quality Remote sensing ecological index Karst mountainous area Ecological fragility Guanling Autonomous County
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New Fragile Watermarking Technique to Identify Inserted Video Objects Using H.264 and Color Features
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作者 Raheem Ogla Eman Shakar Mahmood +1 位作者 Rasha I.Ahmed Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2023年第9期3075-3096,共22页
The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video ind... The transmission of video content over a network raises various issues relating to copyright authenticity,ethics,legality,and privacy.The protection of copyrighted video content is a significant issue in the video industry,and it is essential to find effective solutions to prevent tampering and modification of digital video content during its transmission through digital media.However,there are stillmany unresolved challenges.This paper aims to address those challenges by proposing a new technique for detectingmoving objects in digital videos,which can help prove the credibility of video content by detecting any fake objects inserted by hackers.The proposed technique involves using two methods,the H.264 and the extraction color features methods,to embed and extract watermarks in video frames.The study tested the performance of the system against various attacks and found it to be robust.The evaluation was done using different metrics such as Peak-Signal-to-Noise Ratio(PSNR),Mean Squared Error(MSE),Structural Similarity Index Measure(SSIM),Bit Correction Ratio(BCR),and Normalized Correlation.The accuracy of identifying moving objects was high,ranging from 96.3%to 98.7%.The system was also able to embed a fragile watermark with a success rate of over 93.65%and had an average capacity of hiding of 78.67.The reconstructed video frames had high quality with a PSNR of at least 65.45 dB and SSIMof over 0.97,making them imperceptible to the human eye.The system also had an acceptable average time difference(T=1.227/s)compared with other state-of-the-art methods. 展开更多
关键词 Video watermarking fragile digital watermark copyright protection moving objects color image features H.264
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Influence of Reservoir on Groundwater Environment in the Ecologically Fragile Area, Northwest of China
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作者 Ling Wang Tongqin Liu +2 位作者 Feng Tian Jianguo Feng Guiyu Zhao 《Journal of Water Resource and Protection》 2023年第6期315-331,共17页
As the research proposed reservoirs after impact on the surrounding ecological fragile areas of groundwater level and scope, through the proposed reservoir area and its surrounding data collecting, hydrogeology survey... As the research proposed reservoirs after impact on the surrounding ecological fragile areas of groundwater level and scope, through the proposed reservoir area and its surrounding data collecting, hydrogeology survey and related test, for Modflow system simulation platform, through to the boundary conditions, initial conditions and source sink term and related hydrogeological parameters, the model identification and verification, The model of hydrogeological parameters in the study area is constructed. The simulation results show that the groundwater depth near the reservoir area will be higher than the critical value (1.8 m) of secondary salinization of soil. At the same time, according to the investigation and experiment, if the reservoir does not do seepage treatment, the water infiltration in the reservoir will aggravate the environmental hydrogeological problems in the ecologically fragile area. 展开更多
关键词 Ecologically fragile Area Reservoir Construction GROUNDWATER Numerical Simulation Environmental Influence
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Socio-Economic and Political Analysis of a Fragile State:A Reflection on Ethiopia
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作者 Asayehgn Desta 《Management Studies》 2023年第2期75-83,共9页
A review of the literature indicates that,currently,Ethiopia is now beyond the bounds of fragility.The purpose of the study was to investigate whether Ethiopia was experiencing fragility.After a review of the literatu... A review of the literature indicates that,currently,Ethiopia is now beyond the bounds of fragility.The purpose of the study was to investigate whether Ethiopia was experiencing fragility.After a review of the literature on fragility,a theoretical framework lens on fragility was developed to empirically test Ethiopia’s current condition.A longitudinal analysis indicates that before 2018,Ethiopia was regarded as the central economic engine of sub-Saharan Africa.However,as the current regime reversed Ethiopia’s developmental state model and moved to follow a neo-liberal model,Ethiopia’s economy has gradually diminished.More specifically,during the current regime,Ethiopia has experienced a decline in its Gross Domestic Product,faced rampant unemployment,and encountered an increase in inflation.Its foreign exchange currency reserves have declined below the three-month threshold of hard currency required for a country to import goods and services,and its external debt has extended beyond the country’s GDP.By encouraging armed conflict and widespread insurgencies,the current regime has caused social tension and deep humanitarian crises in Ethiopia-resulting in devastation of health and school facilities and causing more than five million Ethiopians to be displaced.Finally,failing to provide leadership to his people,the current regime in Ethiopia has willingly allowed the incursion of Ethiopia’s sovereignty by foreign forces.The conclusion of the study is that,when observed through the lens of fragility using a longitudinal framework,currently,Ethiopia has traversed beyond fragility and seems to be heading toward balkanization. 展开更多
关键词 FRAGILITY developmental state neo-liberal model LEGITIMACY SOVEREIGNTY
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Lithium chloride ameliorates learning and memory ability and inhibits glycogen synthase kinase-3 beta activity in a mouse model of fragile X syndrome 被引量:3
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作者 Shengqiang Chen Xuegang Luo +6 位作者 Quan Yang Weiwen Sun Kaiyi Cao Xi Chen Yueling Huang Lijun Dai Yonghong Yi 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第31期2452-2459,共8页
In the present study,Fmr1 knockout mice (KO mice) were used as the model for fragile X syndrome.The results of step-through and step-down tests demonstrated that Fmr1 KO mice had shorter latencies and more error cou... In the present study,Fmr1 knockout mice (KO mice) were used as the model for fragile X syndrome.The results of step-through and step-down tests demonstrated that Fmr1 KO mice had shorter latencies and more error counts,indicating a learning and memory disorder.After treatment with 30,60,90,120,or 200 mg/kg lithium chloride,the learning and memory abilities of the Fmr1 KO mice were significantly ameliorated,in particular,the 200 mg/kg lithium chloride treatment had the most significant effect.Western blot analysis showed that lithium chloride significantly enhanced the expression of phosphorylated glycogen synthase kinase 3 beta,an inactive form of glycogen synthase kinase 3 beta,in the cerebral cortex and hippocampus of the Fmr1 KO mice.These results indicated that lithium chloride improved learning and memory in the Fmr1 KO mice,possibly by inhibiting glycogen synthase kinase 3 beta activity. 展开更多
关键词 fragile X syndrome Fmr1 knockout mice step-down test step-through test learning and memory glycogen synthase kinase 3 beta lithium chloride
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STUDY ON METHOD OF QUANTITATIVE ASSESSMENT OF FRAGILE ENVIRONMENT 被引量:2
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作者 赵跃龙 张玲娟 《Chinese Geographical Science》 SCIE CSCD 1999年第2期45-49,共5页
Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyinc... Todaysustainabledevelopmentiscurentlypromoted,butprohibitedbyfragileenvironment.Soinrecentyears,thestudyincludingformationre... 展开更多
关键词 fragile ECO ENVIRONMENT QUANTITATIVE ASSESSMENT INDEX METHOD
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Aberrant crypt focus and fragile histidine triad protein in sporadic colorectal carcinoma 被引量:2
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作者 Kim Vaiphei Aruna Rangan Rajinder Singh 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2012年第12期250-258,共9页
AIM:To characterize aberrant crypt focus (ACF) in adjoining mucosa in sporadic colorectal carcinoma and to evaluate fragile histidine triad (Fhit) protein and Ki67. METHODS:ACF was identified grossly and classified hi... AIM:To characterize aberrant crypt focus (ACF) in adjoining mucosa in sporadic colorectal carcinoma and to evaluate fragile histidine triad (Fhit) protein and Ki67. METHODS:ACF was identified grossly and classified histologically in 75 resected specimens. ACF was typed into hyperplastic ACF (HACF) and dysplastic ACF (DACF). Sections of ACF, carcinoma and normal colonic mucosa as control were studied for Fhit and Ki67 expressions by immunohistochemistry and were grouped according to staining intensity and the number of positive stained cells observed in different histological groups. Comparison was done between the different groups by Pearson's χ 2 test and γ test for the ordinal data. P value < 0.05 was considered as significant.RESULTS:Age range was 40 to 86 years in males (mean = 43.36) and 45 to 70 years in females (mean = 56). HACF was identified in all cases studied in the non-tumorous colonic mucosa; ACF was observed as non-contiguous scattered foci, which supports the hypothesis of acquisition of single focus monoclonality by colonic epithelial cells in tumor generation. Twenty-four (32%) had DACF and were observed as closure to carcinoma foci. Intensity of Fhit expression:(1) HACF 40% exhibited strong intensity, similar to normal, moderate in 36% and weak in 24%; (2) DACF strong in 25%, moderate in 37.5% and weak in 37.5%; and (3) carcinoma negative in 16%, strong in 43% and moderate and weak in 28.5% each. Significant difference was observed in intensity of the Fhit protein expressions by HACF and DACF (P < 0.05). Tumor in older patients showed a stronger Fhit intensity compared to younger patients (P = 0.036). Vegetarian diet intake and nonsmokers showed stronger Fhit intensities. Advanced stage tumor, non-vegetarian diet and younger age was associated with loss of Fhit protein. Ki67 positivity was an extended crypt pattern in HACF and DACF showed extension up to the neck region of the crypts and surface epithelium. Carcinomas showed a marked increase in Ki67 expression (P < 0.05). Fhit protein had an inverse association with Ki67 expression. CONCLUSION:Weaker Fhit intensity was associated with smoking, non-vegetarian diet intake and increasing Ki67 expression. Loss of Fhit protein expression is possibly influenced by environmental factors like smoking and non-vegetarian diet intake. 展开更多
关键词 ABERRANT CRYPT FOCUS Carcinogenesis Colorectal carcinoma Dysplasia fragile HISTIDINE TRIAD PROTEIN Ki67
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GABAB receptor upregulates fragile X mental retardation protein expression in neurons 被引量:1
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《中国药理学通报》 CAS CSCD 北大核心 2015年第B11期84-84,共1页
Aim Fragile X mental retardation protein (FMRP) is an RNA-binding protein important for the control of translation and synaptic function. The mutation or silencing of FMRP causes Fragile X syndrome (FXS) , which l... Aim Fragile X mental retardation protein (FMRP) is an RNA-binding protein important for the control of translation and synaptic function. The mutation or silencing of FMRP causes Fragile X syndrome (FXS) , which leads to intellectual disability and social impairment. γ-aminobutyric acid (GABA) is the major inhibitory neuro- transmitter of the mammalian central nervous system, and its metabotropic GABAB receptor has been implicated in various mental disorders. The GABAB receptor agonist baclofen has been shown to improve FXS symptoms in a mouse model and in human patients, suggesting the role of GABAB receptor on FMRP regulation. Here we investi- gated the signaling events linking the GABAB receptor and FMRP. Methods Western blot was used in this study to detect protein expression and kinase phosphorylation in cerebellar granule neurons. For key molecules in signal- ling pathway, RNAi was used in MEFs to confirm the results in neurons. Results GABAB receptor activation up- regulated cAMP response element binding protein-dependent Fmrp expression in cultured mouse cerebellar granule neurons via two distinct mechanisms: the transactivation of insulin-like growth factor-1 receptor and activation of protein kinase C. In addition, a positive allosteric modulator of the GABAB receptor, CGP7930, stimulated Fmrp expression in neurons. Conclusion These results suggest a role for GABAB receptor in Fmrp regulation and a po- tential interest of GABAB receptor signaling in FXS improvement. 展开更多
关键词 GABAB RECEPTOR fragile X mental RETARDATION protein fragile X syndrome CREB INSULIN-LIKE growthfactor 1 RECEPTOR PKC positive ALLOSTERIC modulator
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Methanol extract of Codium fragile inhibits tumor necrosis factor-ɑ-induced matrix metalloproteinase-9 and invasiveness of MDA-MB-231 cells by suppressing nuclear factor-κB activation 被引量:1
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作者 Matharage Gayani Dilshara Rajapaksha Gedara Prasad Tharanga Jayasooriya +2 位作者 Chang-Hee Kang Yung-Hyun Choi Gi-Young Kim 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第6期520-525,共6页
Objective:To evaluate whether the methanol extract of Codium fragile(MECF) regulates tumor necrosis factor-α(TNF-α)-induced invasion of human breast cancer MDA-MB-231 cells by suppressing matrix metalloproteinase-9(... Objective:To evaluate whether the methanol extract of Codium fragile(MECF) regulates tumor necrosis factor-α(TNF-α)-induced invasion of human breast cancer MDA-MB-231 cells by suppressing matrix metalloproteinase-9(MMP-9).Methods:Reverse transcriptionpolymerase chain reaction(RT-PCR) and western blot analysis were performed to analyze the expression of MMP-9 and nuclear factor-κB(NF-κB) subunits,p65 and p50,and IκB in MDA-MB-231 cells.3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide(MTT) assay was used for cell viability.MMP-9 activity and invasion were measured by gelatin zymography and a matrigel invasion assay,respectively.NF- κB activity was measured by an electrophoretic mobility shift assay and luciferase activity.Results:MECF had no effects on cell viability up to a concentration of 100 μg/mL in human breast cancer MDA-MB-231 cells regardless of the presence of TNF-α.MDA-MB-231 cells that were stimulated with TNF-α showed a marked increase of invasion compared to the untreated control,whereas pretreatment with MECF downregulated the TNF-α-induced invasion of MDA-MB-231 cells.Additionally,zymography,western blot analysis,and reverse transcriptase-polymerase chain reaction(RT-PCR) confirmed that MECF decreased TNF-α-induced MMP-9 expression and activity which is a key regulator for cancer invasion.According to an electrophoretic morbidity shift assay,pretreatment with MECF in MDA-MB-231 cells significantly decreased the TNF-α-induced DNA-binding activity of nuclear factor- κB(NF- κB),which is an important transcription factor for regulating cancer invasion-related genes such as MMP-9.Furthermore,treatment with MECF sustained the expression of p65 and p50 in response to TNF-α in the cytosolic compartment.The luciferase assay demonstrated that MECF attenuated TNF-α-induced NF- κB luciferase activity.Conclusion:MECF exhibited its antiinvasive capability by downregulating TNF-α-induced MMP-9 expression,resulting from the suppression of NF- κB activity in the human breast cancer cell line MDA-MB-231. 展开更多
关键词 Codium fragile INVASION Nuclear factor-κB Matrix metalloproteinase-9 Tumor NECROSIS factor-α
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A New Fragile Watermarking Scheme for Text Documents Authentication 被引量:1
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作者 XIANG Huazheng SUN Xingming TANG Chengliang 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1661-1666,共6页
Because there are different modification types of deleting characters and inserting characters in text documents, the algorithms for image authentication can not be used for text documents authentication directly. A t... Because there are different modification types of deleting characters and inserting characters in text documents, the algorithms for image authentication can not be used for text documents authentication directly. A text watermarking scheme for text document authentication is proposed in this paper. By extracting the features of character cascade together with the user secret key, the scheme combines the features of the text with the user information as a watermark which is embedded into the transformed text itself. The receivers can verify the integrity and the authentication of the text through the blind detection technique. A further research demonstrates that it can also localize the tamper, classify the type of modification, and recover part of modified text documents. The aforementioned conclusion has been proved by both our experiment results and analysis. 展开更多
关键词 fragile text watermarking character cascade tamper localization tamper type classification tamper recovery
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Fragile Watermarking Based on Robust Hidden Information 被引量:1
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作者 张新鹏 王朔中 《Journal of Shanghai University(English Edition)》 CAS 2003年第3期261-264,共4页
Block-wise fragile watermarks can be used to reveal maliciously tampered areas in multimedia products. However a forged content containing a cloned fragile watermark can be constructed by using a series of watermarked... Block-wise fragile watermarks can be used to reveal maliciously tampered areas in multimedia products. However a forged content containing a cloned fragile watermark can be constructed by using a series of watermarked data. To defeat this type of counterfeit attack, a novel fragile watermarking technique is proposed in which different pseudo-random data are selected for different host products, and the generated fragile watermark is dependent upon the selected information. While inserting the fragile watermark, the pseudo-random information is also robustly embedded into the host data. Because of the difference between the selected information, different watermarked data cannot be used to forge illegal contents containing a valid fragile watermark. 展开更多
关键词 digital watermarking information hiding fragile robust.
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Genomic Instability in Cancer II: 4N-Skewed (90°) Reductive Division via Fragile Sites to Fitness Increase for Solid and Hematological Cancer Beginnings 被引量:2
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作者 Kirsten H. Walen 《Journal of Cancer Therapy》 2019年第7期537-564,共28页
The objective herein was to connect the ontogeny process of diplochromosomal, amitotic, 4n-skewed division-system, to cytogenetic deficiency lesions in satellite, repetitive DNAs, especially in the chromosomal fragile... The objective herein was to connect the ontogeny process of diplochromosomal, amitotic, 4n-skewed division-system, to cytogenetic deficiency lesions in satellite, repetitive DNAs, especially in the chromosomal fragile sites, some 100 distributed over the genome. These latter studies had shown that chemical induced replication-stress led to un-replicated lesions in these fragile sites, which from inaccurate repair processes caused genomic instability. In the chain of events of the ontogeny process to the special tetraploidy, it was proposed that primary damaged human cells could undergo replication stress from repair-process present during cell replication, a suggestion verified by X-ray damaged cells producing the unstable fragile sites (see text). The cancer-importance for therapy is recognition of cell cycle change for the 4n derivative fitness-gained, diploid progeny cells. An open question is whether RB controlling G1 to S-period is mutated at this suggested tumorigenesis initiating phase, and if so, with what consequences for therapy. The fragile site studies further showed that repair of repetitive DNAs could produce two types of genomic changes: single gene mutations and CNVs, which were here shown to be chromosomally located on “borders” to repairing satellite lesions. This genomic placement was found to correspond to mutations identified in tumor sequencing (p53, Rb, MYC), favoring a bad luck location for their cancer “mutational nature”. The CNVs in cancers, are here seen as molecular expressions of long-known cytogenetic HSRs and DMs also with demonstrated origin from amplifications of single genes. Over-expression of oncogenes was hinted of being from duplications, but Drosophila genetics demonstrated the opposite, gene inactivation. The reduced eye-size from dominant, BAR-Ultra-Bar-eye phenotypes, was caused by duplications, inactivating the genetic system for eye-size. The finding of CNVs showing “evasion” of the immune system suggests, inactivation of immune-determining genetics. Since mutated genes on borders to satellite DNAs are a fact in hematological cancers, the 4n-skewed division-system is suggested to replace debated leukemogenesis with fitness-gain from molecular mutations. For these cancers the question is how normal bone marrow cells attain genomic damage for special tetraploidy, which was referred to studies of cells moving in artificial marrow-like substrate, needing serious attention. 展开更多
关键词 Centrifugal 90° Turn CENTROSOME Absence Mitotic Slippage Process Diplochromosomes Mutator Mechanism Satellite DNA MUTATIONS fragile Site Instability Repair MUTATIONS Copy Number Variants CHROMOSOME Nuclear Domains HEMATOLOGIC TRANSLOCATIONS Density Bone Marrow Substrate Abnormal Laminar Proteins Chromosome/Gene UPD Haplo-Insufficiency
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The time‑varying effects of oil prices on oil-gas stock returns of the fragile five countries 被引量:1
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作者 Begüm Yurteri Köedağlı Gül Huyugüzel Kışla A.NazifÇtık 《Financial Innovation》 2021年第1期39-60,共22页
This study analyzes oil price exposure of the oil–gas sector stock returns for the fragile five countries based on a multi-factor asset pricing model using daily data from 29 May 1996 to 27 January 2020.The endogenou... This study analyzes oil price exposure of the oil–gas sector stock returns for the fragile five countries based on a multi-factor asset pricing model using daily data from 29 May 1996 to 27 January 2020.The endogenous structural break test suggests the presence of serious parameter instabilities due to fluctuations in the oil and stock markets over the period under study.Moreover,the time-varying estimates indicate that the oil–gas sectors of these countries are riskier than the overall stock market.The results further suggest that,except for Indonesia,oil prices have a positive impact on the sectoral returns of all markets,whereas the impact of the exchange rates on the oil–gas sector returns varies across time and countries. 展开更多
关键词 Sectoral stock return Oil price Time-varying parameter model fragile five
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COUPLING ANALYSES OF FRAGILE ECO-ENVIRONMENT IN THE WEST OF THE SONGNEN PLAIN
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作者 Chang-chun Song Wei Deng +1 位作者 Xin-shan Song Zhao-qing Luan 《Chinese Geographical Science》 SCIE CSCD 2001年第3期61-67,共7页
The fragile eco-environment is a special type of ecosystem,its response to the change of environmental condi -tions is very susceptive.So it is rather prone to be disturbed under unfav orable conditions.Human activity... The fragile eco-environment is a special type of ecosystem,its response to the change of environmental condi -tions is very susceptive.So it is rather prone to be disturbed under unfav orable conditions.Human activity h as greatly changed the geo-chemical process in the ecosystem,thus caused a series o f positive and negative effects.In t he ecosys-tem,especially in the fragile eco-e nvironment,different systems and r egimes are interconnected and interdetermined.For the suntainable development of ecosystem and the protection and rational utilization of resources,it is of great impor-tance to study these internal relati onships and seek rational regulatio n and control measure.This paper tak es the fragile eco-environment in the west of the Songnen Plain as an example.Based on th e study of the topograph,physiognom y,soil,vegetation and their geographic distribution in the landscape,th e paper explains the structure of the ecologic land-scape and quantifies the ecologic ge o-chemical processes under differe nt landscape conditions.In additio n,the paper al-so tries making coupling analyses of the ecologic succession and the landscape geochemical environment.And in the pa-per,some research results are given. 展开更多
关键词 WEST of the Songnen PLAIN fragile ECO-ENVIRONMENT ecologic structure COUPLING of ecologic factors
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The environmental adaptability and reproductive properties of invasive green alga Codium fragile from the Nan'ao Island,South China Sea
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作者 Lanping Ding Xulei Wang +2 位作者 Bingxin Huang Weizhou Chen Shanwen Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第3期70-75,共6页
It has been widely recognized that biological invasion has become one of the greatest threats to the ecosystem.Codium fragile is an invasive species which exhibits a variety of attributes like parthenogenesis,winter f... It has been widely recognized that biological invasion has become one of the greatest threats to the ecosystem.Codium fragile is an invasive species which exhibits a variety of attributes like parthenogenesis,winter fragment,and vegetative reproduction;and therefore,it has become a successful invader,colonizing most subtropical regions.In China’s southeast coastal aquaculture waters,the green algal bloom caused by C.fragile will probably become a serious problem.In order to understand more details about the species,an experiment focused on its reproductive characteristics was conducted using culture established from a sample collected in the aquaculture raft of the Nan’ao Island in the South China Sea.The results showed that there were two types of gametes resembling aplanospores and zoospores respectively,both of which were able to germinate.During the gametes liberation,a long mucilage tube was formed out of the mouth of the gametangium assisting dispersal of gametes away from the parent plant.This tube was adapted not only to its surrounding flowing water environment but also to its parent plant’s outer gelatinous structure.In general,the optimum temperature for gametes release and germination was 15-20℃ and 15℃,respectively,which corresponded to the local offshore marine water.The plant was observed to produce vegetative buds under favourable reproductive conditions which were called propagules.They were capable of developing into filamentous thalli.The results will provide some scientific evidences for revealing the biological mechanism of bloom and control strategies of invasive green algae. 展开更多
关键词 Codium fragile GAMETES PROPAGULES mucilage tube temperature environmental adaptation
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Ferritin,heavy polypeptide 1 interacts with fragile X-related protein 1
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作者 Yun Ma Shuya He +5 位作者 Yang Yang Qiong Chen Weichun Xiao Binyuan Li Jiao Su Xianghui Fu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第10期790-796,共7页
Fragile X-related protein 1(FXR1P) is a member of the FXR gene family,which also includes fragile X mental retardation protein and fragile X-related protein 2(FXR2P).To understand the functions of FXR1P,we screene... Fragile X-related protein 1(FXR1P) is a member of the FXR gene family,which also includes fragile X mental retardation protein and fragile X-related protein 2(FXR2P).To understand the functions of FXR1P,we screened FXR1P-interacting proteins using a yeast two-hybrid system.FXR1P was fused to pGBKT7 and used as the bait to screen a human fetal brain cDNA library.This screening revealed 10 FXR1P-interacting proteins including FTH1.FTH1 encodes Homo sapiens ferritin,heavy polypeptide 1.The interaction between FXR1P and FTH1 was confirmed by retesting in yeast using both a β-galactosidase assay and growth studies on selective media.A co-immunoprecipitation assay in mammalian cells further confirmed the FXR1P/FTH1 interaction.Moreover,the results revealed that FTH1 colocalized with FXR1P in the cytoplasm around the nucleus in mammalian cells.The present findings suggest that FXR1P plays an important role in iron metabolism in the brain by interacting with FTH1.This provides clues for elucidating the relationship between FXR1P function and fragile X syndrome. 展开更多
关键词 fragile X-related protein ferritin heavy polypeptide 1 yeast two-hybrid system interaction
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EXPRESSION OF FRAGILE HISTIDINE TRIAD AND P53 IN NON-SMALL CELL LUNG CANCER
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作者 侯兴华 张道荣 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2006年第2期121-126,共6页
Objective: To investigate the expression offragile histidine triad (FHIT) and p53 protein in non-small cell lung cancer (NSCLC) and explore the relationship between their expressions and the clinicopathological f... Objective: To investigate the expression offragile histidine triad (FHIT) and p53 protein in non-small cell lung cancer (NSCLC) and explore the relationship between their expressions and the clinicopathological features. Methods: FHIT protein and p53 protein were detected by immunohistochemistry in 76 cases of NSCLCs and matched normal lung tissues. Results: Fifty-one cases (67.1%) showed negative expression of FHIT (apparent reduction or loss) and thirty-seven cases (48.7%) showed p53 positive expression (overexpression). The difference was significant (P=0.04). However, there was no significant difference in FHIT expression between the p53-positive group and the p53-negative group (64.9% versus 69.2%, P=0.686). The negative rate of FHIT protein expression was higher in squamous cell carcinoma than in adenocarcinoma, in moderately and poorly differentiated carcinoma than in well-differentiated carcinoma, and in cases with smoking history than in cases without smoking history (P〈0.05). There was no relationship between FHIT expression and clinical stage or lymph node metastasis. The negative FHIT expression was not an independent predictor of overall survival (P=0.338). Conclusion: The frequency of negative expression of FHIT protein is higher than that of positive expression of p53 in NSCLCs. The negative expression of FHIT is independent of the expression of p53. The change of expression of FHIT may play a role in the smoking related lung tumorigenesis while it may have no relationship with the progress of NSCLC or prognosis of the patients. 展开更多
关键词 fragile histidine triad P53 Lung neoplasm Non-small cell lung cancer IMMUNOHISTOCHEMISTRY
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New Semi-Fragile Authentication Watermarking
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作者 孙鑫 易开祥 费敏锐 《Journal of Shanghai University(English Edition)》 CAS 2002年第2期158-162,共5页
In this paper we propose a semi fragile watermarking scheme, which can be used for image authentication. Let the original image be performed by l level discrete wavelet transformation. An approximate wavelet coeffi... In this paper we propose a semi fragile watermarking scheme, which can be used for image authentication. Let the original image be performed by l level discrete wavelet transformation. An approximate wavelet coefficient matrix of the original image and real value chaotic sequences are than used to generate the content based and secure watermark. The watermark is embedded into original image by using HVS. The tamper detection can identify the tampered region of the received watermarked image. Experimental results are given. 展开更多
关键词 fragile watermark AUTHENTICATION chaotic sequences human visual system (HVS) DWT.
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A Rapid Screening and Diagnosis on Fragile X Syndrome by PCR
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作者 陈敬春 杨爱德 +3 位作者 费洪宝 金润铭 何美娟 王碧玉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1999年第2期66-69,共4页
Polymerase chain reaction (PCR) technique combined with direct detection by silver staining on denaturing DNA sequencing gel was used to analyze the (CGG)n repeats within the FMR1 gene on 169 suspected patients wit... Polymerase chain reaction (PCR) technique combined with direct detection by silver staining on denaturing DNA sequencing gel was used to analyze the (CGG)n repeats within the FMR1 gene on 169 suspected patients with mental retardation and 33 kindreds of 6 fragile X families. The results showed that : (1) No PCR products were detected in 3 males in the suspected group. (2) In the fragile X family studies, the 5 male probands failed to show any PCR products. (3) Diplex PCR with the primers flanking the FRAXE locus was used to serve as an internal control for the 8 above mentioned males and only normal products of the FRAXE locus were detected, indicating that the possibility of false negative results of the FRAXA locus could be eliminated. These findings suggested that analysis of (CGG)n repeat within the FMR1 gene by PCR technique could efficiently detect premutation carriers and that negative PCR products in mentally retarded males might highly imply the diagnosis of fragile X syndrome after the false negative results have been excluded by diplex PCR. This PCR assay is suitable for the screening and diagnosis of fragile X syndrome in a large number of populations due to its rapidity, simplicity, stability and reliability. 展开更多
关键词 fragile X syndrome PCR SCREENING DIAGNOSIS
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Litter decomposition in fragile ecosystems:A review
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作者 Hao Qu XueYong Zhao +5 位作者 XiaoAn Zuo ShaoKun Wang XuJun Ma Xia Tang XinYuan Wang Eduardo Medina-Roldán 《Research in Cold and Arid Regions》 CSCD 2022年第3期151-161,共11页
As a linkage between plants and soil,litter decomposition and its effect on nutrient recirculation have an important ecolog‐ical significance as they contribute to soil structure improvement and the restoration of de... As a linkage between plants and soil,litter decomposition and its effect on nutrient recirculation have an important ecolog‐ical significance as they contribute to soil structure improvement and the restoration of degraded ecosystems.Fragile eco‐systems in arid regions(both hot and cold)are depleted in soil organic matter,and as a result of various factors their circu‐lation of material and energy is slower.Here we discuss how litter decomposition is necessary to maintain the stability of fragile ecosystems.We reviewed research on litter decomposition carried out in arid regions.Our objective in this review is to outline how litter decomposition,and the subsequent buildup of organic matter in soil,is a key process determining the stability of fragile ecosystems.Our review shows that existing studies have focused on the influence of single ecologi‐cal factors on litter decomposition and nutrient cycling,and highlights how the exploration of interactions among factors determining litter decomposition is still lacking.This interaction is a key aspect,since in the real world,decomposition and nutrient return to soil of litter products is affected by multiple factors.We propose a network setup on a cross-regional scale using standardized methods(e.g.,the tea bag method)to understand litter decomposition and nutrient return in frag‐ile ecosystems.Such a unique network could contribute to establish predictive models suitable for litter decomposition and nutrient return in these areas,and thus could provide theoretical and practical support for regional ecological protec‐tion and high-quality development. 展开更多
关键词 litter mass loss fragile ecosystems ARID SEMI-ARID hot-deserts cold-deserts
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