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New findings concerning the Pleistocene Glaciation of the Leh Basin,Ladakh(34°03'N/77°38'E)

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Journal of Mountain Science 2010年第4期7卷 367-374页

作者： Hermann Achenbach Geographical Institute University of GoettingenDepartment of High Mountain Geomorphology and Geography

Like for most parts of High Asia,researches concerning the Pleistocene landscape evolution of the Leh Basin(34°03' N/77°38' E) have also left *** push this topic,three up to now unexplored Ladakh Range tributaries of the Leh Basin(Stagmo-,Arzu-and Nang-Valley) have been investigated.U-shaped profiles,transfluence passes,moraine mantled and glacially rounded peaks and ridges,roches moutonnées,glacial flank polishings and ground moraines document the former glaciation of the study *** ice fillings of these tributaries reached a minimum thickness up to 540 *** at the valley outlets and on the orographic right side of the Leh Basin,the glaciation was more than 350 m *** on these empirically extracted results,theoretical snow line considerations lead to the conclusion that the whole Leh Basin was filled up by a former Indus-Valley *** ice injection limited to the nourishment areas of the Ladakh Range valleys could not have caused the reconstructed ice cover(down to 3236 m a.s.l.),which is proved by extended ground moraine *** an Indus ice stream network(most likely during the LGP),nourished by inflowing glaciers of the Ladakh-and Stok Range,explains the widespread existence of the glacial sediments at the outlets of the investigated valleys.

关键词： Glacial-geomorphology Formerglaciation Last glacial period Equilibrium linealtitude High Asia

Molecular Detection of Pathogens Involved in Sexually Transmitted Infections in Brazzaville, Congo

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Open Journal of Medical Microbiology 2024年第3期14卷 190-205页

作者： Jeanine Mireille Sita Maboundou Bitsi Nina Esther Ngoyi Ontsira Edith Sophie Kombo Bayonne Tanguy Mieret Geril Sekangue Obili Herlen Tsoumou Lina Foungou Kessengue Samantha Potokoue Mpia Chloé Dupont Guilhem Conquet Gickel Mpika Bitsene Bienvenu Roland Ibara Ossibi Axel Aloumba Etienne Nguimbi Sylvain Godreuil Faculty of Sciences and Technology Marien NGOUABI University Brazzaville Republic of the Congo Faculty of Health Sciences Marien NGOUABI University Brazzaville Republic of the Congo Bacteriology-Virology Laboratory University Hospital Center Brazzaville Republic of the Congo department of Infectious Diseases Referral Hospital Center of Talanga Brazzaville Republic of the Congo Parasitology-Mycology Laboratory University Hospital Center Brazzaville Republic of the Congo department of Gynecology-Obstetrics University Hospital Center Brazzaville Republic of the Congo UMR IRD224-CNRS5290-UM MIVEGEC Infectious Diseases and Vectors: Ecology Genetics Evolution and Control CREES (Reshearch Center in Ecology and Evolution Health) Montpellier France Bacteriology Laboratory Arnaud de Villeneuve University Hospital CHU of Montpellier Montpellier France department of Infectious Diseases University Hospital Center Brazzaville Republic of the Congo

The objective of this multicentric study was to assess the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma génitalium and Trichomonas vaginalis infections in Brazzaville, in the Republic of Congo, using molecular methods. From January to December 2021, the sexually transmitted disease risk participants were recruited from six centers: The Association of Young HIV-Positive People of Congo, The Congolese Association for Family Welfare, The Association for Support to Vulnerable Groups, Talangaï hospital, Brazzaville university hospital (outpatient service) and the private clinic COGEMO (outpatient service). The real-time multiplex PCR was carried out to detect these pathogens. Each patient had at least one specimen (urine, urethral, anal and/or vaginal samples). The patients were considered infected when one of their samples was positive. 287 participants made of 227 women and 60 men were tested. The general prevalence of these infections was: Chlamydia trachomatis 2.79%, Neisseria gonorrhoeae 3.14%, Mycoplasma génitalium 3.45% and Trichomonas vaginalis 2.97. The prevalence rates according to sex were: C. trachomatis, M. génitalium, N. gonorrhea and T. vaginalis were 1.32%, 2.05%, 1.32% and 3.42% in women and 8.33%, 7.02%, 10% and 1.75% in men, respectively. Most infected patients were asymptomatic. Prevalence rates were higher in bisexual individuals, with the exception of T. vaginalis which showed higher prevalence in heterosexual patients. The bisexual and homosexual individuals represent a major public health problem in sexually active young adults, particularly among men having sex with men. These sexually transmitted infections are mainly asymptomatic, their diagnosis and management remain difficult in developing countries.

关键词： Prevalence Chlamydia trachomatis Neisseria gonorrhoeae Mycoplasma génitalium Trichomonas vaginalis

A high incidence of non-cavity nesting in an introduced population of House Sparrows suggests that the species should not be constrained by cavity-nest site availability

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Avian Research 2017年第4期8卷 202-209页

作者： Elizabeth Louise Sheldon Simon Charles Griffith department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia

Background: The House Sparrow(Passer domesticus) has undergone dramatic population declines in many parts of *** has been widely hypothesised that a lack of cavity nest sites has contributed to this *** the idea of the House Sparrow being nest site limited is somewhat incompatible with the long history of nest site plasticity in the ***: The nest-site selection in a population of non-native House Sparrows introduced to Australia from Europe just over 150 years ago was *** prevalence of non-cavity nesting was quantified,and nest-site selection in terms of landscape and nesting structure were ***: Flexible nesting behaviors were reported over a range of different landscapes and a surprisingly high rate of nesting in vegetation(43%) was *** nests found in vegetation were not in cavities,but were woven into the foliage and supported by branches and ***: The high rate of vegetation nesting indicates that in this introduced population,the House Sparrow is unlikely to be constrained by cavity-nest site *** high degree of nest site plasticity in the Australian population may suggest that European House Sparrows have the potential to shift away from their proclivity for cavity *** work in Europe should examine the incidence of non-cavity nesting in House Sparrows more closely,and perhaps reconsider the idea that House Sparrows are nest-site constrained.

关键词： Passer domesticus Cavity nests House Sparrow decline Nesting plasticity

Environmental engineering of transition metal dichalcogenide optoelectronics

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Frontiers of physics 2018年第4期13卷 21-52页

作者： Trevor LaMountain Erik J. Lenferink Yen-Jung Chen Teodor K. Stanev Nathaniel P. Stern department of Physics and Astronomy Northwestern University Evanston Illinois 60208 USA

The explosion of interest in two-dimensional van der Waals materials has been in many ways driven by their layered geometry. This feature makes possible numerous avenues for assembling and ma- nipulating the optical and electronic properties of these materials. In the specific case of monolayer transition metal dichalcogenide semiconductors, the direct band gap combined with the flexibility for manipulation of layers has made this class of materials promising for optoelectronics. Here, we review the properties of these layered materials and the various means of engineering these properties for optoeleetronics. We summarize approaches for control that modify their structural and chemical en- vironment, and we give particular detail on the integration of these materials into engineered optical fields to control their optical characteristics. This combination of controllability from their layered surface structure and photonic environment provide an expansive landscape for novel optoelectronic phenomena.

关键词： transition metal dichalcogenides optoelectronics van der Waals materials heterostructures excitons

Moth diversity in three biofuel crops and native prairie in Illinois

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Insect Science 2013年第3期20卷 407-419页

作者： Terry Harrison May R. Berenbaum department of Entomology University of Ilfinois at Urbana-Champaign Urbana Illinois USA

The expanding demand for biofuel feedstock may lead to large-scale con- scription of land for monoculture production ofbiofuel crops with concomitant substantial negative impacts on biodiversity. We compared moth diversity in light-trap samples from corn, miscanthus, switchgrass and native prairie, to determine whether there is an observ- able relationship between plant species diversity and moth abundance and diversity. Moth alpha diversity was highest in prairie and was higher in switchgrass than in the other two biofuel crops. Beta diversity generally was low among the biofuel crops, and prairie shared lower beta diversity with switchgrass than with corn or miscanthus. Analysis of variance showed no significant differences in moth abundance per species among treatments. The alpha and beta diversity index findings are consistent with those of other studies on arthro- pods in biofuel crops and provide evidence to suggest that large-scale conversion of acreage to biofuel crops may have substantial negative effects on arthropod biodiversity both within the cropping systems and in the surrounding landscape.

关键词： agricultural landscapes biodiversity bioenergy ecosystem services moths prairies

Spatiotemporal landscape pattern changes and their effects on land surface temperature in greenbelt with semi-arid climate:A case study of the Erbil City,Iraq

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Journal of Arid Land 2024年第9期16卷 1214-1231页

作者： Suzan ISMAIL Hamid MALIKI department of Architecture College of EngineeringSalahaddin UniversityErbil 44002Iraq

Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape *** alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban *** are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation *** they are regarded as a powerful measure for enhancing urban environmental *** the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both ***,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern *** study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study *** results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study *** Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any ***,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and ***,for BU,only aggregation index metric affected LST,while none of VL metrics had a *** study provides insights for landscape pla

关键词： land use and land cover change landscape pattern land surface temperature greenbelt remote sensing

在水资源综合管理中如何体现生态系统的服务功能

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AMBIO－人类环境杂志 2000年第6期29卷 351-353页

作者： Malin falkenmark Carl Folke 周立志 national science Research Council Regeringsgatan 56 SE-103 87 Stockholm Sweden department for Systems ecology SE-106 91 Stockholm Sweden

全球水合作组织(GWP)系由联合国开发计划署和世界银行于1995年发起的一个全球性自愿合作机构,旨在为水资源综合管理(IWRM)提供可行性建议,即包括在不破坏重要生态系统稳定性的前提下,为获得最大经济效益和谋取最大社会福利而进行的水源... 详细信息

全球水合作组织(GWP)系由联合国开发计划署和世界银行于1995年发起的一个全球性自愿合作机构,旨在为水资源综合管理(IWRM)提供可行性建议,即包括在不破坏重要生态系统稳定性的前提下,为获得最大经济效益和谋取最大社会福利而进行的水源、土地和相关资源的协调发展和有效管理。GWP的各项活动将为确保水流域重要生态服务功能得到应有的重视,协助提供必要的基础。为了避免人类赖以生存的生命支持系统遭受破坏,环境资源基础的基本组成部分必须得到保护。

关键词：水资源综合管理生态系统服务功能

Chemical Defense of Soft Coral Sinularia polydactyla from the Red Sea Against Marine Biofilm-Forming Bacteria

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Journal of Ocean University of China 2018年第6期17卷 1451-1457页

作者： ESKandER Rehab AL-SOFYANI Abdulmohsin A. EL-SHERBINY Mohsen M.O. BA-AKDAH Mohammad Abdulaziz SATHEESH Sathianeson department of Marine Biology Faculty of Marine Sciences King Abdulaziz University

Soft corals are an important group of organisms that live in reef ecosystems. In this study, the chemical defense of soft coral Sinularia polydactyla against biofilm-forming bacteria was assessed. The soft coral S. polydactyla was collected from the Obhur creek of the Red Sea and the bioactive compounds were extracted under different conditions using methanol and hexane as solvents. Results revealed that the bioactive compounds produced by the soft coral S. polydactyla were active against the growth, hydrophobicity and extracellular polymeric substances production of the biofilm-forming bacteria. However, the damage or injury in soft coral tissue caused a decrease in the activity against biofilm-forming bacteria. GC-MS analysis revealed that sesquiterpenes were abundant in normal coral sample extract while cembranoids were abundant in damaged coral sample extracts. In general, the results indicated that the soft corals either under stress or with damage may not have a strong chemical defense against the colonizing marine organisms and competitors.

关键词： chemical ecology antifouling antibiofilm activity bioactive compound coral tissue damage

The Genome of Medicinal Plant Macleaya cordata Provides New Insights into Benzylisoquinoline Alkaloids Metabolism

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Molecular Plant 2017年第7期10卷 975-989页

作者： Xiubin Liu Yisong Liu Peng Huang Yongshuo Ma Zhixing Qing Qi Tang Huifen Cao Pi Cheng Yajie Zheng Zejun Yuan Yuan Zhou Jinfeng Liu Zhaoshan Tang Yixiu Zhuo Yancong Zhang Linlan Yu Jialu Huang Peng Yang Qiong Peng dinbo Zhang Wenkai Jiang Zhonghua Zhang Kui Lin Dae-Kyun Ro Xiaoya Chen Xingyao Xiong Yi Shang Sanwen Huang Jianguo Zeng National and Local Union Engineering Research Center of Veterinary Herbal Medicine Resource and Initiative Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients Horticulture and landscape College Veterinary Medicine College Hunan Agricultural University Changsha 410128 China Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture Sino-Dutch Joint Laboratory of Horticultural Genomics Beijing 100081 China Agricuitural Genome Institute at Shenzhen Chinese Academy of Agricultural Sciences Shenzhen 518124 China School of Pharmacy Hunan University of Chinese Medicine Changsha 410208 China MOE Key Laboratory for Biodiversity Science and Ecological Engineering and College of Life Sciences Beijing Normal University Beijing 100875 China Micolta Bioresource Inc. Changsha 410016 China Herbal Extract Engineering Research Center Changsha 410331 China Biotechnology Research Center Hunan Academy of Agricultural Sciences Changsha 410125 China Novogene Bioinformatics Institute Beijing 100083 China department of Biological Sciences University of Calgary Calgary T2N1N4 Canada National Key Laboratory of Plant Molecular Genetics National Plant Gene Research Center Institute of Plant Physiology and Ecology Shanghai Institutes forBiological Sciences Chinese Academy of Sciences Shanghai 200032 China Plant Science Research Center Shanghai Chenshan Botanical Garden Shanghai 201602 China

The overuse of antibiotics in animal agriculture and medicine has caused a series of potential threats to public health. Macleaya cordata is a medicinal plant species from the Papaveraceae family, providing a safe resource for the manufacture of antimicrobial feed additive for livestock. The active constituents from M. cordata are known to include benzylisoquinoline alkaloids （BIAs） such as sanguinarine （SAN） and chelerythrine （CHE）, but their metabolic pathways have yet to be studied in this non-model plant. The active biosynthesis of SAN and CHE in M. cordata was first examined and confirmed by feeding ^13C-labeled tyrosine. To gain further insights, we de novo sequenced the whole genome of M. cordata, the first to be sequenced from the Papaveraceae family. The M. cordata genome covering 378 Mb encodes 22,328 predicted protein-coding genes with 43.5% being transposable elements. As a member of basal eudicot, M. cordata genome lacks the paleohexaploidy event that occurred in almost all eudicots. From the genomics data, a complete set of 16 metabolic genes for SAN and CHE biosynthesis was retrieved, and 14 of their biochemical activities were validated. These genomics and metabolic data show the conserved BIA metabolic pathways in M. cordata and provide the knowledge foundation for future productions of SAN and CHE by crop improvement or microbial pathway reconstruction.

关键词： Macleaya cordata genome Benzylisoquinoline alkaloids Secondary metabolism Sanguinarine Chelerythrine Isotopic labeling