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Exploring the factors affecting carbon and nutrient concentrations in tree biomass components in natural forests,forest plantations and short rotation forestry

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Forest Ecosystems 2018年第4期5卷 498-515页

作者： Roque Rodriguez-Soalleiro Cristina Eimil-Fraga Esteban Gomez-Garda Juan Daniel Garcia-Villabrille Alberto Rojo-Alboreca Fernando Munoz Nerea Oliveira Hortensia Sixto cesar perez-cruzado Sustainable Forest Management Unit (UXFS) Department of Plant Production and Engineering ProjectsUniversidade de Santiago de Compostela (USC)Rua Benigno LedoCampus Terra27002 LugoSpain Centro de Investigacion Forestal de Lourian Xunta de Galicia.Carretera de Marin km 3.536153 PontevedraSpain Sustainable Forest Management Unit (UXFS) Department of Agroforestry EngineeringUniversldade de Santiago de Compostela (USC)LugoSpain Universidad de Concepcion Facultad de Ciencias ForestalesVlctona631 ConcepcionChile Forest Systems and Resources Department Centre for Forest ResearchINIACrta. de la Coruna km 7.528040MadridSpain

Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands,the concentrations usually vary with age, site index and even with tree density. The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry(SRF). Five species(Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components:leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together *** concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional ***: The main sources of variation in nutrient concentrations were biomass component > > genotype(species) ≈ age >tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index(NAI)(+65-85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations(rotation 15 years), debarking the wood at logg

关键词： Nutrient removal Biomass crops Poplar genotypes Eucolyptus Oak Birch Plantation sustainability

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In vitro germination and shoot proliferation of the threatened species Cinchona officinalis L(Rubiaceae).

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Journal of Forestry Research 2016年第6期27卷 1229-1236页

作者： Rosa Armijos-Gonzalez cesar perez-Ruiz Departamento de Ciencias Naturales Universidad Tecnica Particular de LojaCP 1101 608 LojaEcuador Departamento de Biotecnologia y Biologia Vegetal E.T.S.Ingenieros AgronomosUniversidad Politecnica de MadridCP 728040 MadridSpain

Cinchona officinalis （Rubiaceae） is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosystem, C. officinalis populations are threatened. Currently, natural regeneration of the populations is low, despite its high plant regeneration and seed formation capacity. In the present study, an efficient protocol for germination, shoot proliferation and plantlets regeneration was developed for this species. Phenolic content and germination rate of C. officinalis seeds were compared with a control species, C. pubescens. Nodal segments from seedlings of C. officinalis were cultured on Gamborg medium supplemented with different combinations of plant growth regulators. Because the phenol content is high in C. officinalis, the phenolic should be removed with hydrogen peroxide or water washes to stimulate germination. Shoots and callus developed from nodal segments within 45 days using most of the tested combinations of plant growth regulators. The best rates of shoot proliferation, callus formation and adventitious buds were obtained in medium supplemented with 5.0 mg L^-1 6-benzyl-aminopurine and 3.0 mg L^-1 indole- 3-butyfic acid.

关键词： Callus Cinchona officinalis Germination Phenols Rubiaceae Shoot

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A Theoretical Model of the Water Vapor Diffusion through the Surface of Cloud Droplets

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Journal of Earth Science and Engineering 2015年第8期5卷 520-523页

作者： Raul cesar perez Lihando Ceds. Department of Subjects Basics National Technological University Regional Mendoza Faculty Rodriguez 257.Mendoza Argentina

In order to understand better the dynamics of formation, growth and evaporation process of the cloud drops, it had developed a mathematical and physics model, using the equation of the vapor diffusion law get cross its surface, taken into consideration that it has a spherical form. When the spherical drop is formed, its time of live will depend on its radio value a; so, on the one hand, if the a value is bigger than critical radio value, then the drop growth because the condensation process win to the evaporation process, on the other hand, if the a value is less than critical radio value, then the cloud drop will be evaporated. To case the drop growth, the condensation process to the vapor diffusion gets cross its surface government the phenomenal dynamical. This important process is theoretically modeling in order to get a bigger understanding to design more efficient method of modifying them in a benefit way.

关键词： Drop diffusion model water vapor.

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Study of the Influence of Critical Radius on the Cloud Drops Formation in the Seeding Operations

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Journal of Environmental Science and Engineering(A) 2012年第5期1卷 616-619页

作者： Rauil cesar perez Department of Civil Engineering National Technology University Mendoza 5500 Argentina

In the seeding operations in order to mitigate the climatic changes or to intervene beneficently on the precipitations process, it is very important to know the roll of the critical radius size of the cloud drops formation and its posterior evolution. In the seeding operations programs, the fundament is to determinate the critical radius in order to obtain efficient results. So, it must consider （a） the critical radius size necessary in order to get the better results; （b） the atmospheric conditions that determine it. In order to get a methodology to calculate the critical radius in each atmospheric condition, the present work has been developed. And with them, it can estimate the nuclei size necessary in order to assure good seeding. The authors had obtained approximate values that were good enough to the goals.

关键词： Critical radius precipitation modification cloud seeding.

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China's Global Shipping Connectivity:Internal and External Dynamics in the Contemporary Era(1890–2016)

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Chinese Geographical Science 2018年第2期28卷 202-216页

作者： cesar DUCRUET WANG Liehui French National Center for Scientific Research UMR 8504 Geographie-citesParis F-75006France The Center for Modern Chinese City Studies East China Normal UniversityShanghai 200062China School of Urban and Regional Science East China Normal UniversityShanghai 200241China

China's global shipping connectivity had been somewhat overlooked as the bulk of related studies predominantly focused on the throughput volume of its own port cities. This article tackles such lacunae by providing a relational perspective based on the extraction of vessel movement archives from the Lloyd's List corpus. Two complementary analyses are proposed: long-term dynamics with all ships included(1890–2008) and medium-term dynamics focusing on container flows(1978–2016). Each analysis examines China's maritime connectivity in various ways and on different spatial scales, from the global to the local, in terms of concentration, vulnerability, and expansion. The main results underline the influence of technological, economic, and political factors on the changing distribution of connectivity internally and externally. In particular, China has managed to reduce its dependence upon external transit hubs, to increase the internal connectivity of its own port system, and to strengthen its dominance towards an increasing number of foreign nodes and trade partners through the maritime network.

关键词： China connectivity maritime network port system vessel movements

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Calorimetry is not color-blind. Molecular insights on association processes in surfactant-polymer mixtures derived from calorimetric experiments

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Science China Chemistry 2011年第12期54卷 2024-2027页

作者： LOH Watson BRINATTI cesar Institute of Chemistry Universidade Estadual de Campinas(UNICAMP)

This comment will review and discuss recent results obtained with the use of calorimetry in assessing molecular information from complex phenomena such as association in surfactant/polymer mixtures. These examples were selected to support the view that it is possible to ally the great sensitivity of modem calorimeters with carefully planned experiments and, sometimes, ancillary techniques in order to derive detailed information on molecular interactions.

关键词： calorimetry polymer-surfatant interaction self-assembly

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Endoscopic resection of superficial gastrointestinal tumors

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World Journal of Gastroenterology 2008年第29期14卷 4600-4606页

作者： Giovannini Marc cesar Vivian Lopes Endoscopic Unit Paoli-Calmettes Institute232 Bd St-Marguerite Cedex 13273 France

Therapeutic endoscopy plays a major role in the management of gastrointestinal (GI) neoplasia. Its indications can be generalized into four broad categories; to remove or obliterate neoplastic lesion, to palliate malignant obstruction, or to treat bleeding. Only endoscopic resection allows complete histological staging of the cancer, which is critical as it allows stratification and refinement for further treatment. Although other endoscopic techniques, such as ablation therapy, may also cure early GI cancer, they can not provide a definitive pathological specimen. Early stage lesions reveal low frequency of lymph node metastasis which allows for less invasive treatments and thereby improving the quality of life when compared to surgery. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are now accepted worldwide as treatment modalities for early cancers of the GI tract.

关键词： Superficial gastrointestinal cancers Endoscopic mucosal resection Endoscopic submucosaldissection Lymph node spreading Esophagus Stomach Colorectal

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Quite amusing stem cells:Muse cells

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Neural Regeneration Research 2023年第11期18卷 2377-2378页

作者： Molly Monsour cesar V.Borlongan University of South Florida Morsani College of Medicine TampaFLUSA Department of Neurosurgery and Brain Repair University of South FloridaMorsani College of MedicineTampaFLUSA

Stem cells may be the future of therapeutics for stroke due to their regenerative and immunomodulatory *** barriers faced when employing stem cells,however,include faulty migration,low cell survival,and diminished proliferation.M ultilineage-differentiating stress ensuring (Muse) cells,a subset of mesenchymal stem cells,overcome these *** cells aid in neuroregeneration,have immense regenerative potential,and are pluripotent,non-tumorigenic,and *** stroke specifically,these cells may restore an a nti-inflammatory environment,regenerate damaged neurons,and integrate into the neuronal *** fact,Muse cells may be aptly designed to ameliorate neurovascular unit damage following stroke and observed in other neuroinflammatory disorders.

关键词： modulator overcome integrate

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Traumatic brain injury treatment using a rodent model of homelessness

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Neural Regeneration Research 2024年第9期19卷 1873-1874页

作者： Molly Monsour cesar V.Borlongan University of South Florida Morsani College of Medicine TampaFLUSA Center of Excellence for Aging and Brain Repair Department of Neurosurgery and Brain RepairUniversity of South Florida Morsani College of MedicineTampaFLUSA

Introduction:Traumatic brain injury(TBI)is a common diagnosis among veterans secondary to combat *** is also rampant among those experiencing homelessness,possibly due to veterans making up 12.3%of the homeless population(Tsai and Rosenheck,2015),or due to the high risk of violence or trauma among those experiencing *** is up to 10×more prevalent among those experiencing homelessness(Stubbs et al.,2020;Dell et al.,2021).

关键词： diagnosis TBI less

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Going straight for the gut:gut-brain axis pathology and treatment of Parkinson's disease

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Neural Regeneration Research 2024年第10期19卷 2111-2112页

作者： Dominique Ebedes cesar V.Borlongan University of South Florida Morsani College of Medicine TampaFLUSA Center of Excellence for Aging and Brain Repair Department of Neurosurgery and Brain RepairUniversity of South Florida Morsani College of MedicineTampaFLUSA

This perspective focuses on the recent literature regarding the role of the gut-brain axis(GBA) in fecal microbiota transplantation(FMT) and stem cell therapy(SCT) in Parkinson's disease(PD).PD is the second most common neurodegenerative disease in the United States,yet therapies remain *** research suggests that the GBA may play a role in the pathogenesis of *** FMT as well as SCT offer promising new avenues for PD *** bing the interactions between FMT and SCT with the GBA may reveal novel therapeutics for PD.

关键词： straight pathology pathogenesis

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