检索结果-南通市图书馆

Study about Top-Down and Bottom-Up controls in Regulating the Phytoplankton Biomass in a Eutrophic Reservoir in Northeastern Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Water Resource and Protection 2012年第8期4卷 616-621页

作者： Juliana dos Santos Severiano ariadne do Nascimento Moura Enaide Marinho de Melo Magalhaes Viviane Lucia dos Santos Almeida Graduating Program on Botany Rural and Federal University of PernambucoRecifeBrasil Federal University of Alagoas Institute of Biological Sciences and Health—IBSHMaceioBrasil Department of the Environment Prefecture of RecifeOlindaBrasil

This study aims to analyze the effects of nutrients and predation by zooplankton on phytoplankton biomass (chlorophyll a) in a eutrophic reservoir in Brazil (Apipucos Reservoir, State of Pernambuco), through experiments in microcosms. For this, samples of water were placed in 1 L Erlenmeyer flasks and kept for seven days. Treatments included the addition of nutrients (nitrogen combined with phosphorus and isolated additions of nitrogen and phosphorus), with presence and absence of zooplankton and a control which contained the reservoir water without any manipulation. The addition of nutrients did not stimulate phytoplankton growth. However, zooplankton significantly decreased phytoplankton biomass in the treatments it was added to (p cant factor in the regulation of phytoplankton, contradicting several studies which show that phytoplankton biomass is more strongly controlled by nutrients (bottom-up control) than by predation (top-down control).

关键词： chlorophyll α Nutrients Zooplankton Tropical Regions

Increased branching independent of strigolactone in cytokinin oxidase 2-overexpressing tomato is mediated by reduced auxin transport

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Horticulture 2022年第1期2卷 153-171页

作者： Lilian Ellen Pino Joni E.Lima Mateus H.Vicente ariadne F.L.de Sá Francisco Pérez-Alfocea Alfonso Albacete Juliana L.costa TomášWerner Thomas Schmülling Luciano Freschi Antonio Figueira Agustin Zsögön Lázaro E.P.Peres Laboratory of Plant Breeding Centro de Energia Nuclear na AgriculturaUniversity of Sao PauloSão PauloBrazil Laboratory of Hormonal control of Plant Development Department of Biological SciencesEscola Superior de Agricultura‘Luiz de Queiroz’University of Sao PauloPiracicabaBrazil Botany Department ICBFederal University of Minas GeraisBelo HorizonteBrazil Department of Plant Nutrition CEBAS-CSICCampus Univ.EspinardoMurciaSpain Institute of Biology/Applied Genetics Freie Universität BerlinBerlinGermany Institute of Biology University of GrazSchubertstraße 518010 GrazAustria Biosciences Institute University of Sao PauloSão PauloBrazil Plant Sciences Department Federal University of ViçosaViçosaBrazil

Tomato production is influenced by shoot branching,which is controlled by different *** we produced tomato plants overexpressing the cytokinin-deactivating gene cYTOKININ OXYDASE 2(cKX2).cKX2-overexpressing(cKX2-OE)plants showed an excessive growth of axillary shoots,the opposite phenotype expected for plants with reduced cytokinin content,as evidenced by Lc-MS analysis and ARR5-GUS *** TcP transcription factor SlBRc1b was downregulated in the axillary buds of cKX2-OE and its excessive branching was dependent on a functional version of the GRAS-family gene LATERAL SUPPRESSOR(LS).Grafting experiments indicated that increased branching in cKX2-OE plants is unlikely to be mediated by root-derived *** cKX2-OE plants with transgenic antisense plants for the strigolactone biosynthesis gene cAROTENOID cLEAVAGE DIOXYGENASE(ccD7-AS)produced an additive phenotype,indicating independent effects of cytokinin and strigolactones on increased *** the other hand,cKX2-OE plants showed reduced polar auxin transport and their bud outgrowth was reduced when combined with auxin ***,cKX2-OE basal buds did not respond to auxin applied in the decapitated *** results suggest that tomato shoot branching depends on a fine-tuning of different hormonal balances and that perturbations in the auxin status could compensate for the reduced cytokinin levels in cKX2-OE plants.

关键词： cKX2 Hormones Plant development Solanum

chemical Quality of Landrace Varieties cultivated in Traditional communities in the State of Maranhao, Brazil

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Agricultural Science and Technology(B) 2018年第4期8卷 234-241页

作者： Djanira Rubim dos Santos Georgiana Eurides de carvalho Marques Vivian do carmo Loch Roberta Almeida Muniz ariadne Enes Rocha Juliane cutrim Marques Federal Institute of Education Science and Technology of Maranhao Av. Getulio Vargas District Monte Castelo Sao Luis MA65004030 Brazil Department of chemistry Federal Institute of Education Science and Technology of Maranhdo End. Av. Getulio Vargas DistrictMonte Castelo Sao Luis MA 65004030 Brazil State University of Maranhao End of University City Paulo VI Tirirical Soo Luis MA 65055970 Brazil Department of Administration Federal Institute of Education Science and Technology of Maranhao End. Av. Getulio VargasDistrict Monte Castelo Sao Luis MA 65004030 Brazil Department of Phytotechnology State University of Maranhao End of University City Paulo VI Tirirical Sao Luis MA 65055970Brazil

The aim of this study was to analyze the chemical composition of landrace seeds of rice, maize and cassava grown in traditional communities in file state of Maranchao. The sample collection was based on file description of the farmers for identification of varieties of plants, based on protein content, lipids, carbohydrates and mineral through Association of Official Analytical chemists （AOAc） methods. Landrace seeds of nine maize cultivars, 13 rice and 40 cassava, with differences in centesimal composition in all varieties were analyzed. For maize landrace seeds file lipid values, carbohydrates and ash are in the average for the species. The protein contents and ash to file surveyed rice varieties were high, while the levels of lipids and carbohydrates are within average in relation to conventional varieties. The results obtained for cassava showed high percentages of protein, with a significant level for the feeding of the people of the community who consume their byproducts. Thus, differences in file chemical composition of file varieties studied showed file interference of genotype, management and environmental factors in their chemical and physiological quality, reinforcing file importance of file study of creole varieties for the development of new germplasm and for file guarantee of food sovereignty of traditional communities.

关键词： Nutrition seeds sustainability.

Early Detection of White Spot Syndrome Virus(WSSV)in Isolated Hemocytes of Litopenaeus vannamei

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

cellBio 2017年第1期6卷 1-12页

作者： ariadne Hernandez-Perez Rossanna Rodriguez-canul Edgar Torres-Irineo Fernando Mendoza-cano Daniel Eduardo coronado-Molina Jesus Alejandro Zamora-Briseno Jorge Hernandez-Lopez Laboratorio de Inmunología y Biología Molecular Centro de Investigación y de Estudios Avanzados del IPN(CINVESTAV-IPN)Unidad MéridaMéridaMéxico Laboratorio de Pesquerías Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad MéridaMéridaMéxico UMDI-Sisal Facultad de CienciasUniversidad Nacional Autónoma de MéxicoSierra PapacalMéxico centro de Investigaciones Biológicas del Noroeste HermosilloMéxico

To date, White Spot Syndrome (WSS) produced by the White Spot Syndrome Virus (WSSV) causes one of the most severe diseases infecting penaeid shrimps worldwide. Although a vast amount of studies has elucidated pathogenesis in live infection models, there is still little information about the interaction of WSSV infections using in vitro models in the whiteleg shrimp Litopenaeus vannamei (L. vannamei) hemocytes. In this study, a WSSV infection kinetics was performed using total hemocytes isolated from healthy L. vannamei organisms and maintained in in vitro conditions using isotonic solution for shrimp (ISS). The infected experimental cells received ≈ 30,000 viral copies of WSSV. The viability of the hemocytes (control and infected group) was measured during the kinetics with trypan blue exclusion method and cells were maintained up to 6 hpi (post-infection) with non-significant differences of viability between both groups. WSSV replication was assessed using RT- PcR at the RNA expression level of the early viral gene Ie1 and transcripts were detected as early as 30 min pi. Hemocytes from WSSV group showed disrupted integrity, degranulation and irregular shape. This study provides evidence of the capability of WSSV to infect and replicates in L. vannamei hemocytes using in vitro assays in short times as 30 min.

关键词： WSSV Litopenaeus vannamei Ie1 Gene Hemocytes In Vitro Infection GLS Analysis

Presence of Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV) in Native Shrimps from Southern Mexico

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Marine Science 2017年第3期7卷 424-432页

作者： ariadne Hernández-Pérez Jesús Alejandro Zamora-Briseñ o Juan Antonio Pérez Vega Richard Juan de Dios Mena-Loria Daniel coronado-Molina Jorge Hernández-López Norma Angelica-López-Téllez Rossanna Rodríguez-canul Laboratorio de Inmunología y Biología Molecular Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN) Unidad Mérida Yucatán México centro de Investigaciones Biológicas del Noroeste Sonora México centro Regional de Investigación Pesquera de Lerma Campeche Instituto Nacional de la Pesca (CRIP Lerma-INP) Campeche México

A survey for Infectious Hypodermal and Haematopoietic Necrosis Virus (IHHNV) and White Spot Syndrome Virus (WSSV) was performed during two catching seasons of native shrimps in the Yucatan coast in the Gulf of Mexico. The mtDNA cOI barcode identified two endemic species;the southern pink shrimp Penaeus notialis (Pérez Fantante, 1967) and the northern pink shrimp Penaeus brasiliensis (Latreille, 1987) (previously described as Farfantepenaeus brasiliensis). The prevalence of IHHNV was of 18.18% in 2016, and of 8.57% in 2017. All organisms tested negative for WSSV. This is the first identification of wild shrimps in the state of Yucatan Mexico by mtDNA cOI barcode as well as the first identification of IHHNV in such species. The presence of IHHNV in wild shrimps populations has a potential of persisting in the coast of Yucatan with putative detrimental effect on local fisheries because once established in natural waters and hosts;such pathogens are almost impossible to eradicate.

关键词： IHHNV WSSV mtDNA cOI Barcode Penaeus notialis Penaeus brasiliensis Yucatan Peninsula

Reconfiguring wireless environments via intelligent surfaces for 6G: reflection, modulation, and security

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2023年第3期66卷 60-79页

作者： Jindan XU chau YUEN chongwen HUANG Naveed UL HASSAN George c.ALEXANDROPOULOS Marco DI RENZO Mérouane DEBBAH Engineering Product Development Pillar Singapore University of Technology and Design college of Information Science and Electronic Engineering Zhejiang University Department of Electrical Engineering Lahore University of Management Sciences Department of Informatics and Telecommunications National and Kapodistrian University of Athens Technology Innovation Institute Université Paris-Saclay CNRS Centrale Supélec Laboratoire des Signaux et Systèmes

The reconfigurable intelligent surface(RIS) has been recognized as an essential enabling technology for sixth-generation(6G) mobile communication networks. An RIS comprises a large number of small and low-cost reflecting elements whose parameters can be dynamically adjusted with a programmable *** of these elements can effectively reflect a phase-shifted version of the incident electromagnetic wave. By configuring the wave phases in real time, the propagation environment of the information-bearing signals can be dynamically manipulated to enhance communication reliability, boost transmission rate, expand cellular coverage, and strengthen communication security. In this study, we provide an overview on RIS-assisted wireless communications. Specifically, we elaborate on the state-of-the-art enabling techniques for the RIS technology as well as their corresponding substantial benefits from the perspectives of RIS reflection and RIS modulation. With these benefits, we envision the integration of RISs into emerging applications for6G. In addition, communication security is of unprecedented importance in future 6G networks with ubiquitous wireless services in multifarious verticals and areas. We highlight potential contributions of RISs to physical-layer security, in terms of secrecy rate and secrecy outage probability, exemplified by a typical case study from both theoretical and numerical aspects. Finally, we discuss challenges and opportunities on the deployment of RISs in practice to motivate future research.

关键词： reconfigurable intelligent surface physical-layer security RIS-assisted wireless communications phase modulation 6G

Patient-Reported Factors Facilitating Participation in Prevention of Mother to child Transmission of HIV Programs in Kara, Togo, West Africa

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of AIDS 2014年第4期4卷 446-457页

作者： Eméfah c. Loccoh Deladem Azouma Kevin Fiori Jr. Jennifer Schechter Sesso Gbeleou Lisa R. Hirschhorn The University of Michigan Ann Arbor MI USA The University of Lomé Lomé Togo The University of Kara Kara Togo Hope Through Health Medway MA USA L’Association Espoir pour Demain Kara Togo Harvard Medical School Boston MA USA ariadne Labs Boston MA USA

Background: Despite efforts to expand prevention of mother-to-child transmission (PMTcT) of HIV in resource-limited settings, only 53% of women in sub-Saharan Africa receive adequate PMTcT services. Understanding factors that enable successful program completion are crucial to improving adherence rates to PMTcT programs in these settings. Using a positive deviance approach, we explored patient and provider’s perspectives on factors enabling women to successfully access and adhere to PMTcT services to identify areas of program improvement and further reduce HIV transmission. Methods: Semi-structured interviews were conducted with 11 health care workers (HcWs) at two health centers in Kara, Togo and 34 women who had successfully completed the PMTcT program at those facilities. Women were identified using purposive sampling and content theme analysis was used to analyze the data. Results: Knowledge and belief in the potential to give birth to an HIV-negative child, supported by facilitating factors on the individual and community levels, was the cornerstone to women’s PMTcT program success. Effective program education and peer-to-peer interactions fostered the participants’ knowledge and belief in PMTcT, with the resulting internal motivation driving continued participation and adherence. The welcoming environment, availability of peer support groups and financial assistance from the health facility, further facilitated success, with women using this facility-based community to seek advice and support from HcWs and peers. Financial, physical, and emotional support from relatives was also important in ensuring unhindered access. Finally, the faith-based communities’ acceptance and support for HIV-positive women further encouraged participants to adhere to the program. conclusion: Understanding and believing in the ability to have an HIV-negative baby was the most important facilitator for PMTcT program adherence. This led to internal motivation that was continually rein

关键词： Maternal Health Program Adherence AIDS Mother-to-child Transmission HIV Positive Women

Wireless communications empowered by reconfigurable intelligent surfaces: Model-based vs model-free channel estimation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Information and Intelligence 2023年第3期1卷 253-266页

作者： Li Wei chongwen Huang George c.Alexandropoulos Ahmet M.Elbir Zhaohui Yang Zhaoyang Zhang Marco Di Renzo Merouane Debbah chau Yuen Engineering Product Development Pillar Singapore University of Technology and DesignSingapore 487372Singapore college of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Department of Informatics and Telecommunications National and Kapodistrian University of Athens15784 AthensGreece Interdisciplinary centre for Security Reliability and TrustUniversity of LuxembourgL-4365 Esch-sur-AlzetteLuxembourgand Duzce UniversityDuzce 81620Turkey Universite Paris-Saclay CNRSCentraleSupelecLaboratoire des Signaux et Systemes91192France Khalifa University of Science and Technology Abu DhabiUnited Arab Emirates School of Electrical and Electronics Engineering Nanyang Technological UniversitySingapore 639798Singapore

Reconfigurable intelligent surfaces(RISs)are lately being attractive for their great potential in future sixth generation wireless communications(6G),which is attributed to their affordable energy consumption and easy ***,the large numbers of low-cost reflecting elements comprising RISs impose challenges for channel acquisition in various RIS-based wireless applications,such as RIS-enhanced orthogonal frequency-division multiplexing and multi-user multipleinput multiple-output *** this article,we first overview the state-of-the-art RIS hardware architectures designed to assist channel estimation for RIS-empowered wireless communication *** also overview existing channel estimation approaches,which are categorized into model-based and model-free techniques,and discuss their advantages and limitations depending on the RIS *** challenges with RIS-empowered systems in terms of hardware and other parameter limitations are presented,together with future research directions for channel estimation in RIS-based wireless systems,such as RISs with extremely large numbers of elements,multi-hop communications with RISs,and frequency division duplexing for high mobility systems.

关键词： Reconfigurable intelligent surfaces channel estimation Model-based methods Model-free methods