检索结果-南通市图书馆

Vegetation structure,dominance patterns and height growth in an Afromontane forest,Southern Africa

Journal of Forestry Research 2020年第2期31卷 453-462页

作者： Sylvanus Mensah Anthony Egeru Achille Ephrem Assogbadjo romain GleleKakai Laboratoire de Biomathematiques et d’Estimations Forestieres Facultedes Sciences AgronomiquesUniversite d’Abomey-Calavi04 BP 1525 CotonouBenin Regional Universities Forum for Capacity Building in Agriculture Makerere UniversityP.O Box 16811WandegeyaKampalaUganda Laboratoire d’Ecologie Appliquee Facultedes Sciences AgronomiquesUniversite d’Abomey-Calavi03 BP 1974 CotonouBenin

Information on forest structure is fundamentally important to track successional vegetation dynamics for efficient forest *** study reports on vegetation characteristics,dominance patterns and species height growth in a northern mistbelt forest type in South *** alpha-diversity indices(species richness and Shannon-Weiner diversity),structural vegetation parameters(tree density and basal area),and species importance value index were *** class distribution and height-diameter allometry were further examined for the overall stand and most important *** densities(472.0±43.5 and 605.3±28.1 trees ha^-1 for C 5 cm to\10 cm and C 10 cm dbh(diameter at breast height)classes,respectively)and basal area values(1.99±0.19 and 48.07±3.46 m^2 ha^-1,respectively)are comparable to other Afromontane forests in East *** overall stand showed an inverted-J shaped distribution pattern which is a typical feature of stand size class distribution in most natural *** ecologically important species also exhibited an inverted-J shaped distribution pattern,suggesting good regeneration and recruitment *** were significant differences in species on height,reflecting species-specific height growth patterns,possibly a result of intrinsic growth potential and competitive *** present study suggests that conservation and management policies,including protection of surrounding land uses against fire,contribute to maintaining a successful recovery of these ***,it should be noted that these forests may be experiencing relatively slow dynamic flux as a result of the overmature state of some trees with several years under relatively strict protection.

关键词： Diversity Population structure Species composition Size class distribution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tree-ring:a suitable implement for spatial and temporal fire distribution analysis in savanna woodland and dry forest

引用

Journal of Forestry Research 2015年第2期26卷 435-446页

作者： Franck Sinsin romain GlèlèKaka? Bettina Orthmann Brice Sinsin Laboratoire d’Ecologie Appliquée Faculté des Sciences AgronomiquesUniversité d’Abomey-Calavi03 BP 1974 CotonouBénin Laboratory of Biomathematics and Forest Estimations Faculté des Sciences AgronomiquesUniversité d’Abomey-Calavi03 BP 1974 CotonouBénin Institute of Biosciences University of Rostock

Based on 120 stem discs collected during3 months of fieldwork along a 12 km route,the history of fires in the Wari Maro Forest（09 1000 N–02 1000E） over the past century in savanna woodland and dry forest was *** major ecological areas are characterized：one highly burnt zone located between two relative less burnt *** analyzing tree rings,246 fire scars were *** scars were caused by 51 fire years,occurring at a mean interval of 2.23 *** 1890 to1965,only 6 years with fires were recorded from sampled *** 1966,no year has passed without *** fire frequency point scale reached 14 *** was the case of Burkea africana,which has been identified as a species tolerant to fire and could be planted to create a natural *** contrast,Anogeissus leiocarpa is highly sensitive to fire,and in a dry forest ecosystem that burns seasonally,it requires a special conservation *** new concepts are described：the rebarking of trees after fire and Mean Kilometer Fire *** first concept was tested with Daniellia oliveri（Rolfe） Hutch ＆ Dalz trees,and the second concept was used to evaluate spatial fire *** demonstrate that savanna woodland and dry forest were subject to a degradation process caused by destructive fires related to vegetation cover clearance and illegal logging.

关键词： Fire ecology Tree-rings Savanna woodland Dry forest Conservation strategies

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Self-formation of hexagonal nanotemplates for growth of pyramidal quantum dots by metalorganic vapor phase epitaxy on patterned substrates

引用

Nano Research 2016年第11期9卷 3279-3290页

作者： Alessandro Surrente romain Carron Pascal Gallo Alok Rudra Benjamin Dwir Eli Kapon Laboratory of Physics of Nanostructures Ecole Polytechnique Federale de Lausanne CH- 1015 Lausanne Switzerland

We demonstrate the self-formation of hexagonal nanotemplates on GaAs （111）B substrates patterned with arrays of inverted tetrahedral pyramids during metal-organic vapor phase epitaxy and its role in producing high-symmetry, site-controlled quantum dots （QDs）. By combining atomic force microscopy measurements on progressively thicker GaAs epitaxial layers with kinetic Monte Carlo growth simulations, we demonstrate self-maintained symmetry elevation of the QD formation sites from three-fold to six-fold symmetry. This symmetry elevation stems from adatom fluxes directed towards the high-curvature sites of the template, resulting in the formation of a fully three-dimensional hexagonal template after the deposition of relatively thin GaAs layers. We identified the growth conditions for consistently achieving a hexagonal pyramid bottom, which are useful for producing high-symmetry QDs for efficient generation of entangled photons.

关键词： metalorganic vapor phaseepitax kinetic Monte Carlosimulations epitaxial growth onpatterned substrates symmetry elevation adatom diffusion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mitochondrial transport of catalytic RNAs and targeting of the organellar transcriptome in human cells

引用

Journal of Molecular Cell Biology 2023年第8期15卷 40-53页

作者： PawełGłodowicz Konrad Kuczynski romain Val AndréDietrich Katarzyna Rolle Department of Molecular Neurooncology Institute of Bioorganic ChemistryPolish Academy of Sciencesul.Z.Noskowskiego 12/1461-704 PoznanPoland Institute of Plant Molecular Biology French National Center for Scientific Research(CNRS)and University of Strasbourg12 rue du Général Zimmer67084 StrasbourgFrance

Mutations in the small genome present in mitochondria often result in severe *** genetic strategies have been explored,aiming to rescue such mutations.A number of these strategies were based on the capacity of human mitochondria to import RNAs from the cytosol and designed to repress the replication of the mutated genomes or to provide the organelles with wild-type versions of mutant ***,the mutant RNAs present in mitochondria turned out to be an obstacle to therapy and little attention has been devoted so far to their ***,we present the development of a strategy to knockdown mitochondrial RNAs in human cells using the transfer RNA-like structure of Brome mosaic virus or Tobacco mosaic virus as a shuttle to drive trans-cleaving ribozymes into the organelles in human cell *** obtained a specific knockdown of the targeted mitochondrial ATP6 mRNA,followed by a deep drop in ATP6 protein and a functional impairment of the oxidative phosphorylation *** strategy provides a powerful approach to eliminate mutant organellar transcripts and to analyse the control and communication of the human organellar genetic system.

关键词： human cells mitochondria ribozyme RNA trafficking transcriptome manipulation tRNA-like structure

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

EGFR amplification induces sensitivity to antiEGFR therapy in pancreatic acinar cell carcinoma

引用

World Journal of Gastrointestinal Oncology 2018年第4期10卷 103-107页

作者： Corentin Richard Julie Niogret romain Boidot Francois Ghiringhelli Platform of Transfer in Oncology Center GF LeclercDijon 21000France INSERM U1231 Dijon 21000France University of Bourgogne Franche Comte Dijon 21000France Department of Medical Oncology Georges Francois Leclerc Cancer CenterDijon 21000France

Pancreatic acinar cell carcinoma(PACC) is a rare cancer. When the tumor is metastatic, few therapeutic options are available. Precision medicine using next-generation sequencing is defined by the administration of drugs based on the tumor genetic mutations. The usage of precision medicine for finding new therapeutic options for rare cancers is an emerging field. We have reported here the case of a patient bearing a multitreated metastatic PACC. This patient underwent somatic and constitutional exome analyses. The analyses revealed in the liver metastasis an amplification of the EGFR gene. Accordingly, the patient was treated with off-label usage of panitumumab. We observed rapid response with necrosis of the liver metastasis, while no efficacy was observed in the primary tumor. An exome analysis of the primary tumor revealed amplification of HER2 and MET with EGFR amplification. Such amplifications are known as a resistance mechanism to anti EGFR therapy. Our results suggest that exome analysis may be helpful to highlight targets in rare cancers, such as PACC. EGFR amplification in this pathology should be determined and could be used as a biomarker to propose anti EGFR therapy.

关键词： Pancreatic cancer Acinar cell carcinoma Exome Genetic mutations Precision medicine

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nankai Trough Velocity Structure Reconstruction using FWI of Wide-angle OBS Data with Graph-space Optimal Transport Misfit Function

引用

Acta Geologica Sinica(English Edition) 2021年第S01期95卷 11-14页

作者： Andrzej GóRSZCZYK romain BROSSIER Ludovic MéTIVIER ISTerre Université Grenoble AlpesGrenobleFrance Institute of Geophysics Polish Academy of SciencesWarsawPoland Université Grenoble Alpes CNRSLJKGrenobleFrance

Technical development oriented on the detailed seismic imaging and velocity model building coupled with rapid increase of the computing power available nowadays make it possible to process large volumes of seismic dat... 详细信息

关键词： time-domain full-waveform inversion alternative misfit function high-resolution crustal-scale imaging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preoperative albumin level is a marker of alveolar echinococcosis recurrence after hepatectomy

引用

World Journal of Gastroenterology 2017年第5期23卷 853-858页

作者： Gaetan-romain Joliat Ismail Labgaa Nicolas Demartines Nermin Halkic Department of Visceral Surgery University Hospital CHUV1011 LausanneSwitzerland

AIM To identify a preoperative blood marker predictive of alveolar echinococcosis(AE) recurrence after *** All consecutive patients who underwent operation for liver AE at the Lausanne University Hospital(CHUV) between January 1992 and December 2015 were included in this retrospective study. Preoperative laboratory values of leukocytes, mean corpuscular volume(MCV), red blood cell distribution width(RDW), thrombocytes, C-reactive protein(CRP) and albumin were collected and analyzed. Univariate and multivariate Cox regression analyses were performed to determine the risk factors for AE recurrence after liver resection. A receiver operating characteristic(ROC) curve was used to define the best discrimination threshold of the blood marker. Moreover, recurrencefree survival curves were calculated using the KaplanMeier *** The cohort included 68 adult patients(37 females) with median age of 61 years [interquartile range(IQR): 46-71]. Eight of the patients(12%) presented a recurrence over a median follow-up time of 76 mo(IQR: 34-128). Median time to recurrence was 10 mo(IQR: 6-11). Median preoperative leukocyte, MCV, RDW,thrombocyte and CRP levels were similar between recurrent and non-recurrent cases. Median preoperative albumin level was 43 g/L(IQR: 41-45) for nonrecurrent cases and 36 g/L(IQR: 33-42) for recurrent cases(P = 0.005). The area under the ROC curve for preoperative albumin level to predict recurrence was 0.840(95%CI: 0.642-1, P = 0.002). The cutoff albumin level value was 37.5 g/L for sensitivity of 94.5% and specificity of 75%. In multivariate analysis, preoperative albumin and surgical resection margins were independent predictors of AE recurrence(HR = 0.099, P = 0.007 and HR = 0.182, P = 0.045 respectively).CONCLUSION Low preoperative albumin level was associated with AE recurrence in the present cohort. Thus, preoperative albumin may be a useful biomarker to guide follow-up.

关键词： Liver surgery Alveolar echinococcosis Albumin Predictive marker Recurrence

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Evidence for the effect of brief exposure to food,but not learning interference,on maze solving in desert ants

引用

Integrative Zoology 2022年第5期17卷 704-714页

作者： Tomer GILAD Arik DORFMAN Aziz SUBACH romain LIBBRECHT Susanne FOITZIK Inon SCHARF School of Zoology The George S.Wise Faculty of Life SciencesTel Aviv UniversityTel AvivIsrael Institute of Organismic and Molecular Evolution Johannes Gutenberg University MainzMainzGermany

Theories of forgetting highlight 2 active mechanisms through which animals forget prior knowledge by recipro-cal disruption of *** to“proactive interference,”information learned previously interferes with the acquisition of new information,whereas“retroactive interference”suggests that newly gathered information interferes with already existing *** goal was to examine the possible effect of both mechanisms in the desert ant Cataglyphis niger,which does not use pheromone recruitment,when learning spatial information while searching for food in a *** experiment indicated that neither proactive nor retroactive interference took place in this system although this awaits conﬁrmation with individual-level learning ***,the ants’persistence or readiness to search for food grew with successive runs in the *** persistence led to more ant workers arriving at the food when retested a day later,even if the maze was shifted between *** support thisﬁnding in a second experiment,where ant workers reached the food reward at the maze end in higher numbers after encountering food in the maze entry compared to a treatment,in which food was present only at the maze *** result suggests that spatial learning and search persistence are 2 parallel behavioral mechanisms,both assisting foraging *** suggest that their relative contribution should depend on habitat complexity.

关键词： binary-tree maze desert ants forgetting memory motivation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mating behavior of Psammotettix alienus （Hemiptera： Cicadellidae）

引用

Insect Science 2018年第1期25卷 148-160页

作者： Maja Derlink Isabelle Abt romain Mabon Charlotte Julian Meta Virant-DoberletI Emmanuel Jacquot Department of Organisms and Ecosystems Research National Institute of Biology Vecna pot 111 1000 Ljubljana Slovenia INRA- Cirad-Montpellier SupAgro UMR 385 BGPI Cirad TA A-54K 34398 Montpellier France Bayer CropScience 16 rue Jean Marie Leclair - CS 90106 69266 Lyon Cedex 09 France

The Wheat dwarf virus, the causal agent of the wheat dwarf disease, is trans- mitted by leafhoppers from the genus Psammotettix and currently the main protection strategy is based on the use of insecticide treatments. Sustainable management strategies for insect vectors should include methods that are targeted to disrupt reproductive behavior and here we investigated the mating behavior of Psammotettix alineus （Dahlbom 1850） in order to determine the role of vibrational signals in intra-specific communication and pair formation. Both genders spontaneously emit species- and sex-specific calling songs that consisted of regularly repeated pulse trains and differ primarily in pulse train duration and pulse repetition time. Females preferred the conspecific male calling song. After a coordinated exchange of pulse trains, the male approached the stationary female. During the close range courtship and also immediately prior to copulatory attempts distinct male vibrational signals associated with wing flapping and wing vibrations were recorded from the substrate. In the presence of a receptive female, competing males emitted vibrational signals most likely aimed to interfere with male-female interaction. Mated females re- gained sexual receptivity after they laid eggs. Although results suggest that the viruliferous status of insects may have an effect on vibrational songs, our current results did not reveal a significant effect of virus on leafhopper performance in mating behavior. However, this study also suggests, that detailed understanding ofplant-vecto^virus interactions relevant for vector mating behavior is essential for trying new approaches in developing future control practices against plant viruses transmitted by insect vectors.

关键词： mating behavior Psammotettix alienus vibrational communication wheat dwarf virus

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Capturing Near-Equilibrium Solutions: A Comparison between High-Order Discontinuous Galerkin Methods and Well-Balanced Schemes

引用

Communications in Computational Physics 2019年第6期26卷 1-34页

作者： Maria Han Veiga David A.Velasco-Romero Remi Abgrall romain Teyssier Institute of Computational Science University of ZurichSwitzerland Institute of Mathematics University of ZurichSwitzerland Universidad Autonoma del Estado de Morelos Mexico Instituto de Ciencias Fisicas Universidad Nacional Aut́onoma de ḾexicoMexico

Equilibrium or stationary solutions usually proceed through the exact balance between hyperbolic transport terms and source terms. Such equilibrium solutions are affected by truncation errors that prevent any classical numerical scheme from capturing the evolution of small amplitude waves of physical significance. In order to overcome this problem, we compare two commonly adopted strategies: going to very high order and reduce drastically the truncation errors on the equilibrium solution, or design a specific scheme that preserves by construction the equilibrium exactly, the so-called well-balanced approach. We present a modern numerical implementation of these two strategies and compare them in details, using hydrostatic but also dynamical equilibrium solutions of several simple test cases. Finally, we apply our methodology to the simulation of a protoplanetary disc in centrifugal equilibrium around its star and model its interaction with an embedded planet, illustrating in a realistic application the strength of both methods.

关键词： Numerical methods benchmark well-balanced methods discontinuous Galerkin methods

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：