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Structural effects of reedbed grazing and its cessation on reed-nesting songbird densities

Avian Research 2024年第2期15卷 238-248页

作者： Thomas Pagnon clemence Pechinot Lea Sgro j.remie Demay Remi j.llian Regis Gallais Brigitte Poulin Cyril Marmoex Theria Ecologie 6 avenue des martyrs05400VeynesFrance UMR 6249 Chrono-Environnement CNRSUniversite de Franche-Comte16 route de Gray25000BesanconFrance Conservatoire d’Espaces Naturels d’Occitanie 26 alle de Mycenes34000MontpellierFrance Office Français de la Biodiversite 12 cours Lumiere94300VincennesFrance Tour du Valat Research Institute for the Conservation of Mediterranean Wetlands Le Sambuc13200ArlesFrance

Reedbeds are crucial breeding habitats for vulnerable songbird *** of their protection status,these habitats may be threatened by organic matter accumulation,progressively leading to structural homoge-nization and habitat succession towards *** prevent excessive litter build-up with various in-terventions opening-up the reedbeds,such as grazing,which may be detrimental or suitable for some reed bird *** assessed the effects of extensive grazing by horses and its cessation in the medium and long terms on reedbed structure,and the consequences on reed-nesting songbird densities in Estagnol Nature Reserve,a pro-tected wetland near the French Mediterranean *** compared reedbed structural features between grazed,newly ungrazed and old-ungrazed *** nine years,we censused four songbird species in spring and collected water level data in the same survey *** reduced reedbed extent,rej.venated the vegetation with more short green stems on a thinner litter,and produced higher structural heterogeneity and discontinuity compared to long-lasting non *** ungrazed plot showed intermediate *** surveyed songbird total densities were similar among plots while species numbers and densities *** reedbed was more attractive to Moustached Warblers(Acrocephalus melanopogon)and Great Reed Warblers(Acrocephalus arundi-naceus),likely due to the large edges and the high vegetation structural ***,Moustached Warblers were more negatively affected by higher water level in grazed reedbed,presumably because flooding prevents litter *** newly ungrazed reedbed was not preferred by any *** warbler species were found under low density in the old-ungrazed reedbed,where Reed Buntings(Emberiza schoeniclus)were exclu-sively *** availability related to thick litter layer may explain this *** Reed Warblers(Acrocephalus scirpaceus)were found everywhere in similar

关键词： Bird conservation Edge complexity Fragmentation Habitat management Horse grazing Phragmites australis Reed passerine

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Synthesis of Chitosan Quaternary Ammonium Salts

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Chinese Chemical Letters 2001年第12期12卷 1081-1084页

作者： Xu, WL Wu, j.Fu, cl Zhej.ang Univ Dept Chem Hua Jia Chi Sect Hangzhou 310029 Peoples R China

A series of N-alkyl or N-aryl chitosan quaternary ammonium salts were prepared via Schiffs base intermediates. Quaternization of N-substituted chitosan derivatives was carried out using methyl iodide to produce water-soluble cationic chitosan quaternary ammonium salt. The products were characterized by IR, (HNMR)-H-1 and elemental analysis. The degree of substitution of chitosan quaternary ammonium salt was calculated by elemental analysis.

关键词： synthesis quaternization chitosan quaternary ammonium salts

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Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng Yanming Ma Chris j.Pickard Hanyu Liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior

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Effect of humidity on the surface adhesion force of inorganic crystals by the force spectrum method

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Chinese Science Bulletin 2001年第11期46卷 912-914页

作者： Tang, j.Wang, C Liu, MZ Su, M Bai, cl Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Effect of relative humidity on the surface adhesion force of several inorganic crystals of mica, CaF2 and KC1 was studied by atomic force microscopy (AFM). The results showed that the magnitude of surface adhesion force is mainly dependent on the surface free energy of the adsorbed liquid film, but almost independent of the thickness of the film. Furthermore, the deliquescence on the crystal surface was investigated, which demonstrated the capability of the force spectrum method to monitor changes in ionic concentrations of adsorbed liquid film in real-time.

关键词： mica CaF2 KC1 adhesion force relative humidity AFM.

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Synthesis of single-walled carbon nanotubes by the vertical floating catalyst method

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Chinese Science Bulletin 2002年第2期47卷 158-161页

作者： Zhu, HW Li, XS Lij.e, C Xu, cl Liang, j.Wu, DH Tsing Hua Univ Dept Mech Engn State Key Lab Automot Safety & Energy Beijing 100084 Peoples R China

The vertical floating catalyst method is first used to produce single-walled carbon nanotubes (SWNTs) continuously on a large scale by a newly developed technique and pyrolysis of n-hexane. Diameter distributions, micro-structure and purity of the SWNTs film, rope and web are measured by Raman spectroscopy and electron microscope. The results show that SWNTs product has a high degree of orientation, a wide distribution of diameters (0.7-2.0 nm) and high purity of > 80 %.

关键词： single-walled carbon nanotubes (SWNT) vertical floating catalyst method Raman spectroscopy.

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Pregnancy stressors and postpartum symptoms of depression and anxiety:the moderating role of a cognitivebehavioural therapy(CBT)intervention

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General Psychiatry 2024年第1期37卷 112-121页

作者： Yunxiang Sun Soim Park Abid Malik Naj.a Atif Ahmed Zaidi Atif Rahman Pamela j.Surkan Department of International Health Johns Hopkins University Bloomberg School of Public HealthBaltimoreMarylandUSA Department of Public Mental Health Health Services AcademyIslamabadPakistan Human Development Research Foundation RawalpindiPakistan Department of Primary Care and Mental Health Institute of Population HealthUniversity of LiverpoolLiverpoolUK

Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and *** We investigated the association between positive and negative stress events during different stages of pregnancy and postpartum mental health outcomes among low-income pregnant women with symptoms of anxiety in Pakistan and evaluated whether an intervention based on cognitive behavioural therapy(CBT)had a regulatory *** Participants were 621 pregnant Pakistani women with mild *** the Pregnancy Experience Scale-Brief Version,six scores were created to assess positive and negative *** performed a multivariate linear regression to examine whether these six scores,measured both at baseline and in the third trimester,were associated with postpartum anxiety and depressive *** effect of the intervention on this relationship was examined by adding an interaction term to the regression *** Hassles frequency measured in the third trimester was positively associated with depression(B=0.22,95%confidence interval(cl):0.09 to 0.36)and anxiety(B=0.19,95%cl:0.08to 0.30).At the same timepoint,uplifts intensity was negatively associated with symptoms of depression(B=-0.82,95%cl:1.46 to-0.18)and anxiety(B=-0.70,95%cl:-1.25 to-0.15),whereas hassles intensity was positively related to symptoms of depression(B=1.02,95%cl:0.36 to 1.67)and anxiety(B=0.90,95%cl:0.34 to 1.47).The intensity ratio of hassles to uplifts reported in the third trimester was positively related to both depression(B=1.40,95%cl:0.59 to 2.20)and anxiety(B=1.26,95%cl:0.57 to 1.96).The intervention strengthened the overall positive effects of uplfts and the negative effects of *** experiences at baseline during early pregnancy to mid-pregnancy were not associated with mental health *** Stressors in the third trimester but not earlier in pregnancy were associated with postpartum symptoms

关键词： postpartum stress behaviour

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Bulking Up the Bay-Position Substituents Enables Enhanced Selectivity of C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina F.Farac Alan j.Lough Timothy P.Bender Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

The precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional ***,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable for this purpose yet synthetically challenging due to random mixtures of C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric compounds that form during traditional statistical mixed ***,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted C_(s)-symmetric hybrid and complete suppression of sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=cl or F)in their peripheral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed *** findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical *** straightforward approach achieved improved selectivity and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

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Effects of self-administered exercises based on Tuina techniques on musculoskeletal disorders of professional orchestra musicians: a randomized controlled trial

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j.urnal of Integrative Medicine 2015年第5期13卷 314-318页

作者： cláudia Maria Sousa Daniela Coimbra j.rge Machado Henry j.Greten Institute of Biomedical Sciences Abel Salazar University of Porto Porto Polytechnic Institute Superior School of Music and Performing Arts German Society of Traditional Chinese Medicine Heidelberg School of Chinese Medicine

BACKGROUND： Musicians are frequently affected by playing-related musculoskeletal disorders （PRMD）. Common solutions used by Western medicine to treat musculoskeletal pain include rehabilitation programs and drugs, but their results are sometimes disappointing. OBj.CTIVE： To study the effects of self-administered exercises based on Tuina techniques on the pain intensity caused by PRMD of professional orchestra musicians, using numeric visual scale （NVS）. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS： We performed a prospective, controlled single-blinded, randomized study with musicians suffering from PRMD. Participating musicians were randomly distributed into the experimental （n = 39） and the control （n = 30） groups. After an individual diagnostic assessment, specific Tuina self-administered exercises were developed and taught to the participants. Musicians were instructed to repeat the exercises every day for 3 weeks. MAIN OUTCOME MEASURES： Pain intensity was measured by NVS before the intervention and after 1, 3, 5, 10, 15 and 20 d of treatment. The procedure was the same for the control group, however the Tuina exercises were executed in points away from the commonly-used acupuncture points. RESULTS： In the treatment group, but not the control group, pain intensity was significantly reduced on days 1, 3, 5, 10, 15 and 20. CONclUSION： The results obtained are consistent with the hypothesis that self-administered exercises based on Tuina techniques could help professional musicians controlling the pain caused by PRMD. Although our results are very promising, further studies are needed employing a larger sample size and double blinding designs.

关键词： Tuina musculoskeletal disorders professional orchestra musicians randomized controlled trial

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Exploring the effects of taurolidine on tumor weight and microvessel density in a murine model of osteosarcoma

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Oncology Research 2024年第7期32卷 1163-1172页

作者： LISANNE K.A.NEIj.NHUIS LEUTA L.NAUMANN SONIA A.M.FERKEL SAMUEL j.S.RUBIN STEPHAN ROGALLA Division of Gastroenterology and Hepatology Department of MedicineSchool of MedicineStanford UniversityStanford94305USA Department of Surgery Leiden University Medical CenterLeiden2333 ZAThe Netherlands Centre for Human Drug Research Leiden2333 CLThe Netherlands Department of General VisceralVascular and Thoracic SurgeryCharite University Medicine BerlinBerlin10117Germany

Background:Osteosarcoma is the most common malignant primary bone *** prognosis for patients with disseminated disease remains very poor despite recent advancements in ***,current treatment regimens bear a signiﬁcant risk of serious side ***,there is an unmet clinical need for effective therapies with improved safety proﬁ*** is an antibacterial agent that has been shown to induce cell death in different types of cancer cell ***:In this study,we examined both the antineoplastic and antiangiogenic effects of taurolidine in animal models of osteosarcoma.K7M2 murine osteosarcoma cells were inj.cted,both intramuscular and intraperitoneal,into 60 BALB/c mice on day *** were then randomized to receive treatment with taurolidine 2%(800 mg/kg),taurolidine 1%(400 mg/kg),or Nacl 0.9%control for seven days by intravenous or intraperitoneal ***:After 35 days,mice were euthanized,and the tumors were harvested for *** mice were excluded from the analysis due to *** weight was signiﬁcantly lower in the 2%taurolidine intraperitoneal treatment group from day 9 to 21,consistent with elevated mortality in this *** tumor weight was signiﬁcantly lower in the 1%(p=0.003)and 2%(p=0.006)intraperitoneal taurolidine treatment groups compared to the *** antineoplastic effects were observed on intramuscular tumors or for intravenous administration of *** were no signiﬁcant differences in microvessel density or mitotic rate between treatment *** body weight and elevated mortality in the 2%taurolidine intraperitoneal group suggest that the lower 1%dose is ***:In conclusion,there is no evidence of antiangiogenic activity,and the antitumor effects of taurolidine on osteosarcoma observed in this study are ***,its toxic proﬁle grants further *** these observations,further research is necessary to

关键词： Osteosarcoma Taurolidine Cancer treatment Chemotherapy Murine models

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Immediate effects of Tuina techniques on working-related musculoskeletal disorder of professional orchestra musicians

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j.urnal of Integrative Medicine 2015年第4期13卷 257-261页

作者： cláudia Maria Sousa Luis Moreira Daniela Coimbra j.rge Machado Henry j.Greten University of Porto Institute of Biomedical Sciences Abel Salazar j.an Piaget Health Superior School Research in Education and Community Intervention–RECI Porto Polytechnic Institute Superior School of Music and Performing Arts German Society of Traditional Chinese Medicine Heidelberg School of Chinese Medicine

BACKGROUND：Musicians are a prone group to suffer from working-related musculoskeletal disorder（WRMD）.Conventional solutions to control musculoskeletal pain include pharmacological treatment and rehabilitation programs but their effi ciency is sometimes ***：The aim of this research is to study the immediate effects of Tuina techniques on WRMD of professional orchestra musicians from the north of ***,SETTING,PARTICIPANTS AND INTERVENTIONS：We performed a prospective,controlled,single-blinded,randomized *** orchestra musicians with a diagnosis of WRMD were randomly distributed into the experimental group（n=39）and the control group（n=30）.During an individual interview,Chinese diagnosis took place and treatment points were *** acupoints were treated by Tuina techniques into the experimental group and non-specifi c skin points were treated into the control *** was measured by verbal numerical scale before and immediately after ***：After one treatment session,pain was reduced in 91.8%of the cases for the experimental group and 7.9%for the control ***：Although results showed that Tuina techniques are effectively reducing WRMD in professional orchestra musicians of the north of Portugal,further investigations with stronger measurements,double-blinding designs and bigger simple sizes are needed.

关键词： diagnosis(TCM) stress Tuina musicians musculoskeletal disorders

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