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New Host Molecules with Imidazoliums as Functional Arms:Syntheses and Anion Recognition

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Chinese Journal of Chemistry 2002年第5期20卷 447-452页

作者： Yuan, Y Jiang, ZL Gao, G Zhang, GL You, JS Xie, rg Sichuan Univ Dept Chem Chengdu 610064 Peoples R China Daxian Teachers Coll Dept Chem Sichuan 635000 Peoples R China Chinese Acad Sci Chengdu Inst Biol Chengdu 610041 Peoples R China

The bridged tri imidazoliums 3·3X --5·3X - (X -=PF - 6, Br -, I -) and bis imidazoliums 6·2PF - 6 were synthesized by N quaternization of imidazole derivative 1 in acetonitrile under reflux. UV spectroscopic titration experiments showed that the halide salts and hexafluorophosphate salts of these imidazoliums exhibited good recognition toward anions in water and in acetonitrile, respectively.

关键词： anion recognition imidazolium synthesis UV titration supramolecular chemistry

Six forests in one:Tree species diversity in the Bosque Protector Chongón Colonche,a lowland mountain range in coastal Ecuadorian

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Forest Ecosystems 2022年第6期9卷 725-733页

作者： Oswaldo Jadan David ADonoso Edwin Ponce-Ramírez franz Pucha-Cofrep Omar Cabrera Facultad de Ciencias Agropecuarias Universidad de Cuenca12 de Octubre y Diego de TapiaCuenca010107Ecuador Programa de Doctorado en Conservacion de Recursos Naturales Escuela Internacional de DoctoradoUniversidad Rey Juan CarlosMostolesMadridES-28933Spain Departamento de Biología Escuela Politecnica NacionalLadron de Guevara E11⋅253Quito170525Ecuador Geoforest S.A 12 de febrero y Av.Franklin VegaMacas140150Ecuador Grupo de Investigacion Hidrología y Climatología Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador Brandenburg University of Technology(BTU)Cottbus-Senftenberg 03044CottbusGermany Departamento de Ciencias Biologicas y Agropecuarias Universidad Tecnica Particular de LojaSan Cayetano Alto S/NLoja110101Ecuador

Tropical mountain ranges shape the structure of tree communities and promote highly diverse natural ***“Bosque Protector Chong on-Colonche”(BPCC),an 86,000-ha mountain formation situated on the coast of Ecuador,is biogeographically important for the region by connecting floristic elements of the wet Choco and the dry Tumbesian *** understanding of the factors that model tree and palm diversity and distribution in this mountain range are *** measured and identified all trees and palms(DBH≥10 cm)in 289 plots of0.2 ha,distributed throughout *** used generalized linear models to explain the relationship between forest diversity and structure and climatic variables(temperature,rain,aridity),and *** then used cluster and non-metric multidimensional scale(NMDS)analyses to search for distinct forest communities within the *** partition(varpart)was used to determine which predictor variables best explained these distinct forest communities.A species indicator analysis identified the species most likely to define these distinct forest ***,we carried out a niche modeling approach to identify the potential distribution of these forest communities within *** total,we identified 220 tree and palm species in our *** average number of species per plot was 17.8±5.8,ranging from 3 to 40 *** methods sorted the 289study plots into six different forest communities,three communities in the dry forest and three in the semi-humid Garúa *** and temperature,but not altitude or aridity,explained floristic *** results emphasize the high but little cataloged diversity in the lowland mountain rainforests of coastal Ecuador.

关键词： Chongón-Colonche Climatic variables Dry forest Forest communities Garúa forest

Potential of Thai Bast Fibers for Injection Molded PLA Composites

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Journal of Renewable Materials 2023年第5期11卷 2279-2300页

作者： Nina Graupner Thiprada Poonsawat Koranat Narkpiban Jörg Müssig The Biological Materials Group Department of BiomimeticsHSB-City University of Applied SciencesBremenD-28199Germany Department of Botany Faculty of Liberal Arts and ScienceKasetsart UniversityKamphaeng SaenNakhon Pathom73140Thailand Bioproduct Science Department of ScienceFaculty of Liberal Art and ScienceKasetsart UniversityKamphaeng SaenNakhon Pathom73140Thailand Department of Science and Mathematics Faculty of Science and TechnologyRajamangala University of Technology Tawan-OkChonburi20110Thailand

Thailand has a huge variability of bast fiber plants,some of which have been little researched regarding their applicability in *** fiber(bundle)s from different species were investigated and incorporated into a polylactide(PLA)matrix by injection *** and kenaf were used as well-studied fibers,while roselle,Fryxell and paper mulberry are less extensively *** strength,tensile modulus and interfacial shear strength(IFSS)of single fiber(bundle)s were highest for hemp,followed by kenaf,roselle,Fryxell and paper *** the lower tensile strength and IFSS of paper mulberry,the highest tensile strength was achieved for the paper mulberry/PLA composite followed by hemp/*** electron microscope(SEM)analyses showed that the single cells in paper mulberry fiber bundles,in contrast to the other fiber types investigated,were only partially bonded to each other,which explains the lower strength of the fiber *** higher aspect ratio of fiber(bundle)s of paper mulberry in the PLA composite can explain the good composite *** from hemp,paper mulberry shows the best reinforcing effect in the PLA matrix and offers interesting potential for composite *** to neat PLA,the tensile strength could be increased by 24%and the tensile modulus by 54%.

关键词： Mechanical properties interfacial shear strength aspect ratio roselle Fryxell paper mulberry

The Role of the Innate Immune System of the Liver in the Control of HBV and HCV

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Virologica Sinica 2008年第2期23卷 116-123页

作者： Ruth Brring Jrg F. Schlaak Department of Gastroenterology University Hospital of Essen

Hepatitis B virus (HBV) and Hepatitis C virus (HCV) infection are among the most frequent causes of chronic liver disease worldwide. As recent studies suggested that Toll like receptor (TLR)-based therapies may represent a promising approach in the treatment of HBV infection, we have studied the role of the local innate immune system of the liver as possible mediator of this effect. Murine non-parenchymal liver cells (NPC; Kupffer cells, KC; sinusoidal endothelial cells, LSEC) were isolated from C57/BL6 and stimulated by TLR 1-9 agonists. Supernatants were harvested and assayed for their antiviral activity against HBV in HBV-Met cells and HCV in the murine HCV replicon cell line MH1. Only supernatants from TLR 3 and -4 stimulated KC and TLR 3 stimulated LSEC were able to potently suppress HBV and HCV replication. By using neutralizing antibodies we could demonstrate that the TLR 3-but not the TLR 4 mediated effect is exclusively mediated through IFN-β. Our data indicate that TLR 3 and -4 mediated stimulation of NPC leads to production of IFN-β which can potently suppress HBV and HCV replication. This is of relevance for the local control of viral hepatitis infection by the innate immune system of the liver, the development of novel TLR-based therapeutic approaches and sheds new light on the viral crosstalk between HCV (TLR 3 stimulator) and HBV.

关键词： Hepatitis B Kupffer cells Sinusoidal endothelial cells Interferon

Toddy Palm (Borassus Flabellifer) Fruit Fibre Bundles as Reinforcement in Polylactide (PLA) Composites: An Overview About Fibre and Composite Characteristics

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Journal of Renewable Materials 2019年第8期7卷 693-711页

作者： Nina Graupner Koranat Narkpiban Thiprada Poonsawat Porntip Tooptompong Jörg Müssig The Biological Materials Group Department of BiomimeticsHSB-City University of Applied SciencesBremenGermanyNeustadtswall 30D-28199 BremenGermany Bioproduct Science Department of ScienceFaculty of Liberal Arts and ScienceKasetsart University1 Malaiman RdKamphaeng SaenNakhon Pathom 73140Thailand Department of Botany Faculty of Liberal Arts and ScienceKasetsart University1 Malaiman RdKamphaeng SaenNakhon Pathom 73140Thailand Textile Technology and Innovation Research Unit Department of Textile ScienceFaculty of Agro-IndustryKasetsart University50 Thanon Ngam Wong WanKhwaeng Lat YaoKhet ChatuchukBangkok 10900Thailand Department of Science and Mathematics Faculty of Science and TechnologyRajamangala University of Technology Tawan-OkChonburi 20110Thailand

Toddy palm fruit have an apparent density below 0.8 g/cm³and offer an interesting lightweight construction potential in polylactide(PLA)composites reinforced with 37 mass-%*** fibre bundles show similar mechanical properties compared with coir:tensile strength of 240 MPa,Young´s modulus of 3.8 GPa and an elongation at break of 31%.However,density and diameter(~50μm)of fruit fibre bundles are significantly *** compression moulded composites have a density of 0.9 g/cm³and achieved an unnotched Charpy impact strength of 12 kJ/m^(2),a tensile strength of 25 MPa,Young’s modulus of 1.9 GPa and an elongation at break of 9%.Due to the high porosity of the composites and the different stress-strain behaviour of fibre and matrix the fibre-reinforcement potential could not be fully *** stress of the composite was reached at the elongation at break of the PLA-matrix(~2%)while the fibre achieved its maximum stress at an elongation of~31%.After reaching the maximum stress of the composite,the fibres were pulled out from the matrix with low energy absorption,resulting in a decrease in stress and a limited reinforcement ***,the study investigates whether an insect attack by the Asian fruit fly on the mesocarp has a significant influence on the mechanical fibre *** results have shown that only the rough surface of the fibre bundles is smoothed by insect *** mechanical properties were not significantly *** this reason insect-infested fruits of the toddy palm,which are no longer suitable for food production,can be used for the production of sustainable composite materials.

关键词： Toddy palm fibre Borassus flabellifer fibre polylactide(PLA)composite impact strength fibre/matrix adhesion

Investigations on the aging behavior of transparent bioplastics for optical applications

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InfoMat 2020年第2期2卷 424-433页

作者： Jana Baltscheit Nico Schmidt Finn Schröder Jörg Meyer Photonics and Materials Science Hamm-Lippstadt University of Applied ScienceLippstadtGermany Department of Natural Science Paderborn UniversityPaderbornGermany

In this study,the optical properties of transparent bioplastics have been *** long-term technological goal is to establish biopolymers in a new market segment for demanding optical applications and to contribute to a more sustainable economy.A collection of transparent bioplastics has been tested with respect to the long-term stability and the possibility of an application in optical components for LED *** focus of materials testing was on the influence of short wavelength visible radiation as well as thermal *** results show,that some materials may be candidates for subsequent feasibility *** the best of our knowledge,the application of such polymers in complex technical products and in particular in luminaires has not yet been *** use of bio-based plastics for optical components therefore represents a novelty and has a high development potential.

关键词： (blue)LED irradiance (photo)degradation biobased plastics renewable materials transparent optics

“When you’re down, stay down”:A lesson for all competitive alpine skiers supported by an ACL rupture measured in vivo

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Journal of Sport and Health Science 2022年第1期11卷 14-20页

作者： Jörg Spöorri Erich Müller Josef Kröoll Sports Medical Research Group Department of OrthopaedicsBalgrist University HospitalUniversity of ZurichZurich 8008Switzerland University Centre for Prevention and Sports Medicine Department of OrthopaedicsBalgrist University HospitalUniversity of ZurichZurich 8008Switzerland Department of Sport Science and Kinesiology University of SalzburgHallein-Ri 5400Austria

Background:During an experiment,a ski racer equipped with various measurement devices suffered an anterior cruciate ligament(ACL)rupture in his right *** aim of this study was to describe the underlying injury mechanism from a functional ***:Eight giant slalom turns(i.e.,4 left turns),followed by 1 left turn at which the ACL injury occurred,were recorded by 2 video cameras,electromyography of 4 relevant muscle groups,inertial measurement units to measure knee and hip angles,and pressure insoles to determine ground reaction ***:Due to a loss of balance,the ski racer began to slide sideways at the apex of a left *** sliding,his right(outside)leg was actively abducted upward without touching the *** ski racer then attempted to stand up again by dropping his leg back towards the snow *** end of this dropping was accompanied by a decrease in electromyographic activity in the knee stabilizing *** the inside edge of the outer ski caught the snow surface,a rapidly increasing peak force,knee flexion,and an aggressive sudden activation of the vastus medialis muscle were observed,while biceps femoris and rectus femoris further decreased their activation *** likely resulted in excessive anterior translation of the tibia relative to the femur,causing damage to the ***:Our example emphasizes that ski racers should not get up until they stop ***:“When you’re down,stay down.”

关键词： Alpine skiing Athletes Injury mechanism Injury prevention Knee injuries

Assessing hydrological and provisioning ecosystem services in a case study in Western Central Brazil

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Ecological Processes 2014年第1期3卷 248-262页

作者： Lars Koschke Carsten Lorz Christine Fürst Tobias Lehmann franz Makeschin Department of Soil Science and Site Ecology Dresden University of TechnologyPienner Str.1901737 TharandtGermany Faculty for Woods and Forestry Forest PedologyGeology and Site EcologyHochschuleWeihenstephan-TriesdorfUniversity of Applied SciencesFreisingGermany Center for Development Research Department of Ecology and Natural Resources ManagementUniversity of BonnWalter-Flex-Str.353113 BonnGermany

Introduction:Current land use in the Federal District,Western Central Brazil,causes problems related to the water supply which are linked to the regulation of ecosystem services(ES).In scope of an Integrated Water Resources Management concept,we further developed the web-based planning support tool GISCAME for the Pipiripau river basin case ***:We introduced analyses on ecosystem potentials in the raster-based tool to assess,in a spatially explicit manner,the scenario impact on water purification,sediment retention,water retention,and provision of food and fodder in order to identify potential pathways for conserving water *** demonstrate the method,we assess ES depending on a number of land use/land cover change(LULCC)***:We found that a considerable increase of water purification and sediment retention is difficult to achieve with realistic small scale LULCC,mainly because in areas with a low potential to provide hydrological ES and thus with a high demand for sustainable land use,such as native Savanna(Cerrado)and natural forests(Mata),favorable land uses were often already *** observed synergies in the response of regulating hydrological ES to LULCC but at the same time also trade-offs with provision of food and ***:Our findings suggest that further degradation and loss of Cerrado and Mata must be avoided and their restoration should be promoted in order to safeguard water *** suggest that restoration measures should be focused on arable land located at steep slopes near surface waters to effectively increase hydrological ES through the marginal reduction of provision services.

关键词： services retention provision

Calcium-Dependent Protein Kinase CPK21 Functions in Abiotic Stress Response in Arabidopsis thaliana

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Molecular Plant 2011年第1期4卷 83-96页

作者： Sandra franz Britta Ehlert Anja Liese Joachim Kurth Anne-Claire Cazale Tina Romeis Department of Plant Biochemistry Institute for Biology Freie Universitat Berlin Koenigin-Luise-Str. 12-16 14195 Berlin Germany Department of Plant Microbe Interactions Max-Planck-lnstil:ute for Plant Breeding Research Carl-von-Linne-Weg 10 50935 Cologne Germany Present address: Laboratoire des Interactions Plantes Micro-organismes (LIPM) UMR CNRS-INRA 25941441 31320 Castanet-Tolosan France

Calcium-dependent protein kinases （CDPKs） comprise a family of plant serine/threonine protein kinases in which the calcium sensing domain and the kinase effector domain are combined within one molecule. So far, a biological function in abiotic stress signaling has only been reported for few CDPK isoforms, whereas the underlying biochemical mechanism for these CDPKs is still mainly unknown. Here, we show that CPK21 from Arabidopsis thaliana is biochemically activated in vivo in response to hyperosmotic stress. Loss-of-function seedlings of cpk21 are more tolerant to hyperosmotic stress and mutant plants show increased stress responses with respect to marker gene expression and metabolite accumulation. In transgenic Arabidopsis complementation lines in the cpk21 mutant background, in which either CPK21 wildtype, or a full-length enzyme variant carrying an amino-acid substitution were stably expressed, stress responsitivity was restored by CPK21 but not with the kinase inactive variant. The biochemical characterization of in planta synthesized and purified CPK21 protein revealed that within the calcium-binding domain, N-terminal EF1- and EF2-motifs compared to C-terminal EF3- and EF4-motifs differ in their contribution to calcium-regulated kinase activity, suggesting a crucial role for the N-terminal EF-hand pair. Our data provide evidence for CPK21 contributing in abiotic stress signaling and suggest that the N-terminal EF-hand pair is a calcium-sensing determinant controlling specificity of CPK21 function.

关键词： Abiotic/environmental stress calcium signaling/transport Arabidopsis CDPK EF-hand.