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Rs3213758 in the RPGRIPIL Gene Associated with susceptibility to Segmental Vitiligo in a Chinese Han Population

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Chinese Medical Journal 2018年第24期131卷 3022-3024页

作者： Man Hu Ting-Mei Wang Ying-Ying Dong Qiu-Yun She Sheng Gao Dong-Xian Liu Yun-Hua Deng Department of Dermatology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Department of Dermatology Wuhan Center HospitalWuhanHubei 430014China

To the Editor:Vitiligo is an acquired chronic depigrnentation disorder of the skin resulting from selective destruction of melanocytes.Although it is not a life-threatening disease,it may lead to disfigurement and is associated with many other autoimmune diseases.According to a recent international consensus conference,vitiIigo can be cIassified into two major forms: nonsegmental vitiligo (NSV)and segmental vitiligo (SV,accounts for 5-16% of all vitiligo cases).NSV typically evolves over time, in both distribution and extension patterns,including acrofacial, generalized,mucosal,and facial vitiligo [Figure 1a and 1b].SV is relatively rare and is characterized by unilateral or banded distribution along the ganglion segment.SV usually has an early onset and spreads rapidly in the affected dermatomal area,including single SV,double SV,and the multi-SV [Figure 1c and 1d].

关键词： Rs3213758 RPGRIPIL Gene Associated susceptibility Segmental Vitiligo

susceptibility of microorganism to selected medicinal plants in Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 911-917页

作者： S.M.Masud Rana Md.Mustahsan Billah Mohammad Salim Hossain A.K.M.Saifuddin S.K.M.Azizul Islam Sujan Banik Zannatul Nairn Golam Sarwar Raju Department of Pharmacy Noakhali Science and Technology UniversitySonapurNoakhali-3814Bangladesh Department of Physiology Biochemistry and PharmacologyChittagong Veterinary and Animal Sciences UniversityChittagongBangladesh Department of Pharmacy Atish Dipankar University of Science and TechnologyBananiDhakaBangladesh

Objective:To analyze in-vitro antimicrobial activities of some ethno-pharmacologically significant medicinal plants(methanol extract) against the pathogenic microorganisms(Escherichia coli,Salmonella spp..Bacillus cereus.Staphylococcus aureus.Aspergillus niger and Candida albicans).Methods:The disc diffusion method was applied for antibacterial test and the poisoned food technique was applied for antifungal test.Results:The methanol extract of Terminalia chebula(bark),Fhyllanthus acidus(fruits).Sarcochlamys pulcherrima(leaves) and Abelmoschus esculcntus(fruits) had significant in vitro antibacterial activity angainst the entire test samples in comparison to standard drug ciprofloxacin.Most of the plant extracts showed low activity against Gram negative bacteria while potential activity against Gram positive bacteria.The antifungal activities of methanol extracts of these plants and standard drug griseofulvin were determined against two pathogenicfungi,and Polygonum Iapathifolium(leaves) and Cinnamomum tamala(leaves) showed maximum activity,while Erioglossum rubiginosum(leaves) showed no antifungal activity.Conclusions:Further chemical and pharmacological investigations are required to identify and isolate chemical constituents responsible for these potential bioactivities and thus to determine their full spectrum of efficacy.

关键词： susceptibility Zone of inhibition Percentage of inhibition Antibacterial activity Antifungal activity

Landslide susceptibility: a statistically-based assessment on a depositional pyroclastic ramp

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Journal of Mountain Science 2019年第3期16卷 561-580页

作者： Franny G.MURILLO-GARCíA Stefan STEGER Irasema ALCáNTARA-AYALA Institute of Geography National Autonomous University of Mexico (UNAM) Institute for Earth Observation Eurac Research

This study aimed to produce a high-quality landslide susceptibility map for Teziutlán municipality, a landslide-prone region in Mexico, which is characterised by a depositional pyroclastic ramp. The heterogeneous quality of available topographic information(i.e. higher resolution digital elevation model only for a sub-region) encouraged to confront modelling results based on two different study area delineations and two raster resolutions. Input data was based on the larger modelling region L15(163 km2) and smaller S(70 km2; located inside L15) with an associated raster cell size of 15 m(region L15 and S15) and 5 m(region S5). The resulting three data sets(L15, S15 and S5) were included into three differently flexible modelling techniques(Generalized Linear Model-GLM, General Additive Model-GAM, Support Vector Machine-SVM) to produce nine landslide susceptibility models. Preceding variable selection was performed heuristically and supported by an exploratory data analysis. The final models were based on the explanatory variables slope angle, slope aspect, lithology, relative slope position, elevation, convergence index, distance to streams, distance to springs and topographic wetness index. The ability of the models to classify independent test data was elaborated using a k-fold cross validation procedure and the AUROC(Area Under the Receiver Operating Characteristic) metric. In general, all produced landslide susceptibility maps depicted the hillslopes of the ravines, which cut the pyroclastic ramp, as prone to landsliding. The modelling results showed that predictive performances(i.e. AUROC values) slightly increased with an increasing flexibility of the applied modelling technique. Thus, SVM performed best, while the GAM outperformed the GLM. This tendency was most distinctive when modelling with the largest landslide sample size(i.e. data set L15; n = 662 landslides). Non-linear classifiers(GAMs, SVMs) performed slightly better when trained on the basis of lower raster resolution(data set S15) compared to the

关键词： Landslide susceptibility Pyroclastic ramp Logistic regression Generalized Additive Model Support Vector Machine Cross validation

Distribution and susceptibility Assessment of Collapses and Landslides in the Riparian Zone of the Xiaowan Reservoir

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Chinese Geographical Science 2019年第1期29卷 70-85页

作者： ZHONG Ronghua HE Daming HU Jinming DUAN Xingwu HUANG Jiangcheng CHENG Xupeng Institute of International Rivers and Eco-security Yunnan University Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Yunnan University

The southwest alpine gorge region is the major state base of hydropower energy development in China and hence planned many cascading hydropower stations. After the reservoir impoundment, the intense water level fluctuations under the interaction of cascade dams operating and the mountainous flooding, usually cause bank collapse, landslide and debris flow hazards. The Xiaowan reservoir(XWR), for example, as the ‘dragon head' meg reservoir located in the middle mainstream of Lancang River, have resulted in a series of geohazards during its building and operating. In this study, we investigated the number and surface area of collapses and landslides(CLs) occurred in the water level fluctuations zone(WLFZ) of XWR using remote sensing images of Gaofen-1 and Google Earth; evaluated the CLs susceptibility using information value method. The results presented that the total WLFZ area of 87.03 km2 and 804 CLs masses with a total area of 1.98 km2 were identified in the riparian zone of XWR. CLs mainly occurred at an elevation of 1190–1240 m, and the CLs density increased with an increase in altitude. The WLFZ with a slope gradient of 25°– 45° is the main CLs distribution area that accounts for more than half of the total CLs area. The susceptibility assessment revealed that high and very high susceptibility zones are generally distributed along zones with an elevation of 1210–1240 m, a slope degree of 25°–45° and a slope aspect perpendicular to the direction of Lancang River. Furthermore, these susceptible zones are close in distance to the dam site and tend to be in the riparian zones with the formation lithology of Silurian strata. These results provide a valuable contribution to prevent and control geohazards in the XWR area. Moreover, this study offers a constructive sample of geohazards assessment in the riparian zone of large reservoirs throughout the mountains of southwest China.

关键词： susceptibility assessment collapses and landslides water level fluctuations Xiaowan Reservoir Lancang-Mekong River

GIS-based landslide susceptibility mapping using hybrid integration approaches of fractal dimension with index of entropy and support vector machine

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Journal of Mountain Science 2019年第6期16卷 1275-1293页

作者： ZHANG Ting-yu HAN Ling ZHANG Heng ZHAO Yong-hua LI Xi-an ZHAO Lei School of Earth Science and Resources Chang’an UniversityKey Laboratory of Degraded and Unutilized Land Remediation EngineeringMinistry of Land and ResourcesShaanxi Provincial Key Laboratory of Land RehabilitationXi’an 710064China School of Geological and Surveying&Mapping Engineering Chang’an UniversityXi’an 710064China Shaanxi Provincial Land Engineering Construction Group Xi’an 710075China College of Geology&Environment Xi’an University of Science and TechnologyXi’an 710054China

The loess area in the northern part of Baoji City, Shaanxi Province, China is a region with frequently landslide occurrences. The main aim of this study is to quantitatively predict the extent of landslides using the index of entropy model(IOE), the support vector machine model(SVM) and two hybrid models namely the F-IOE model and the F-SVM model constructed by fractal dimension. First, a total of 179 landslides were identified and landslide inventory map was produced, with 70%(125) of the landslides which was optimized by 10-fold crossvalidation being used for training purpose and the remaining 30%(54) of landslides being used for validation purpose. Subsequently, slope angle, slope aspect, altitude, rainfall, plan curvature, distance to rivers, land use, distance to roads, distance to faults, normalized difference vegetation index(NDVI), lithology, and profile curvature were considered as landslide conditioning factors and all factor layers were resampled to a uniform resolution. Then the information gain ratio of each conditioning factors was evaluated. Next, the fractal dimension for each conditioning factors was calculated and the training dataset was used to build four landslide susceptibility models. In the end, the receiver operating characteristic(ROC) curves and three statistical indexes involving positive predictive rate(PPR), negative predictive rate(NPR) and accuracy(ACC) were applied to validate and compare the performance of these four models. The results showed that the F-SVM model had the highest PPR, NPR, ACC and AUC values for training and validation datasets, respectively, followed by the F-IOE model.Finally, it is concluded that the F-SVM model performed best in all models, the hybrid model built by fractal dimension has advantages than original model, and can provide reference for local landslide prevention and decision making.

关键词： GIS Landslide susceptibility Hybrid model Fractal dimension

Comparison of different sampling strategies for debris flow susceptibility mapping: A case study using the centroids of the scarp area, flowing area and accumulation area of debris flow watersheds

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Journal of Mountain Science 2021年第6期18卷 1476-1488页

作者： GAO Rui-yuan WANG Chang-ming LIANG Zhu College of Construction Engineering Jilin UniversityChangchun 130012China

The quality of debris flow susceptibility mapping varies with sampling strategies. This paper aims at comparing three sampling strategies and determining the optimal one to sample the debris flow watersheds. The three sampling strategies studied were the centroid of the scarp area(COSA), the centroid of the flowing area(COFA), and the centroid of the accumulation area(COAA) of debris flow watersheds. An inventory consisting of 150 debris flow watersheds and 12 conditioning factors were prepared for research. Firstly, the information gain ratio(IGR) method was used to analyze the predictive ability of the conditioning factors. Subsequently, 12 conditioning factors were involved in the modeling of artificial neural network(ANN), random forest(RF) and support vector machine(SVM). Then, the receiver operating characteristic curves(ROC) and the area under curves(AUC) were used to evaluate the model performance. Finally, a scoring system was used to score the quality of the debris flow susceptibility maps. Samples obtained from the accumulation area have the strongest predictive ability and can make the models achieve the best performance. The AUC values corresponding to the best model performance on the validation dataset were 0.861, 0.804 and 0.856 for SVM, ANN and RF respectively. The sampling strategy of the centroid of the scarp area is optimal with the highest quality of debris flow susceptibility maps having scores of 373470, 393241 and 362485 for SVM, ANN and RF respectively.

关键词： Debris flow Artificial neural network Support vector machine Random forest susceptibility Sampling strategy

Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles

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Science China Earth Sciences 2010年第7期53卷 1071-1078页

作者： ZHAO XiangYu1,2 & LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China

Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the Chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles.

关键词： Néel theory temperature dependence of susceptibility grain size distribution

Study of third-order nonlinear susceptibility of polySchiff base containing triphenylamine

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Science China Chemistry 2007年第2期50卷 230-237页

作者： NIU HaiJun WANG Wen HUANG YuDong ZHANG YunDong ZHANG YunJun BAI XuDuo LIU Yuan Key Laboratory of Color and Macromolecular Chemistry Heilongjiang UniversityHarbin 150080China Institute of Advanced Ceramic Harbin Institute of TechnologyHarbin 150001China Department of Applied Chemistry Harbin Institute of TechnologyHarbin 150001China Institute of Opto-electronics Harbin Institute TechnologyHarbin 150001China

PolySchiff base containing triphenylamine has been synthesized by polycondensation and character-ized by FT-IR,NMR,UV-visible spectrometer. Measurements of the third-order optical nonlinear sus-ceptibility χ(3) by Z-scan technique have shown that the large nonlinearity is dominated by the two-photon absorption in PSB. The sign and size of real part Reχ(3) ,nonlinear refractive index n2 have been measured with the condition of 532 nm,8 ns-duration pulses to be -1.23×10-10 esu,-3.06×10-12 esu;nonlinear absorption index β and size of image part Imχ(3) to be 3.63×10-10 m/W,1.15×10-11 esu,respec-tively,so the third-order nonlinear susceptibility χ(3) is 1.19×10-11 esu. The value is larger than other polymers reported. PSB is self-focusing material and has potential application in nonlinear optic field.

关键词： polySchiff base triphenylamine third-order susceptibility Z-scan

Magnetic susceptibility inversion method with full tensor gradient data using low-temperature SQUIDs

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Petroleum Science 2019年第4期16卷 794-807页

作者： Yan-Fei Wang Liang-Liang Rong Long-Qing Qiu D.V.Lukyanenko A.G.Yagola Key Laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China Institutions of Earth Science Chinese Academy of SciencesBeijing 100029China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Physical Faculty Lomonosov Moscow State UniversityMoscowRussia 119991

Full tensor magnetic gradient measurements are available nowadays. These are essential for determining magnetization parameters in deep layers. Using full or partial tensor magnetic gradient measurements to determine the subsurface properties, e.g., magnetic susceptibility, is an inverse problem. Inversion using total magnetic intensity data is a traditional way.Because of di culty in obtaining the practical full tensor magnetic gradient data, the corresponding inversion results are not so widely reported. With the development of superconducting quantum interference devices(SQUIDs), we can acquire the full tensor magnetic gradient data through field measurements. In this paper, we study the inverse problem of retrieving magnetic susceptibility with the field data using our designed low-temperature SQUIDs. The solving methodology based on sparse regularization and an alternating directions method of multipliers is established. Numerical and field data experiments are performed to show the feasibility of our algorithm.

关键词： Full tensor magnetic gradient susceptibility Sparse regularization