Emergence of a non-scaling degree distribution in bipartite networks: a numerical and analytical study

We study the growth of bipartite networks in which the number of nodes in one of the partitions is kept fixed while the other partition is allowed to grow. We study random and preferential attachment as well as combination of both. We derive the exact analytical expression for the degree-distribution of all these different types of attachments while assuming that edges are incorporated sequentially, i.e., a single edge is added to the growing network in a time step. We also provide an approximate expression for the case when more than one edge are added in a time step. We show that depending on the relative weight between random and preferential attachment, the degree-distribution of this type of network falls into one of four possible regimes which range from a binomial distribution for pure random attachment to an u-shaped distribution for dominant preferential attachment

A model to define operational irrigation frequency for maximum yield of crops.

Se describe un modelo para definir la frecuencia operacional de riego para obtener maxima produccion de los cultivos. El modelo usa como informacion basica la respuesta de la planta e las condiciones de humedad en el suelo, caracteristicas de retencion y movimiento del agua en el suelo, evapotranspiracion y demanda atmosferica. Se presentan los resultados de la aplicacion del modelo en cultivos de tomate y frijol, en un suelo franco arenoso. Se discute el uso de la informacion mundial de la relacion entre rendimiento de los cultivos y el potencial matricial de agua en el suelo

Efeito de diferentes níveis de irrigação na produção comercial de tomate industrial.

Os objetivos do presente estudo consistiram em avaliar os efeitos de 5 níveis de irrigação sobre a produção do tomate, e determinar a distribuição do sistema radicular

Analise da producao de cebola sob diferentes regimes de irrigacao.

Usando-se um delineamento de blocos casualizados, com cinco tratamentos e cinco repeticoes, estudou-se o efeito de diferentes regimes de irrigacao sobre a producao e tamanho dos bulbos de cebola, variedade Amarelo Chata das canarias. Por ocasiao da colheita determinaram-se a producao e o peso medio dos bulbos. Para a producao de bulbos, verificou-se a diferenca significativa ao nivel de 5% de probabilidade entre os tratamentos de irrigacao

Influência da vermiculita na retenção de água e capacidade de troca de cations em latossolo vermelho amarelo.

Foram estudados os efeitos da adição de vermiculita sobre a retenção de água pelo solo e capacidade de troca de cations (CTC), a fim de verificar a possibilidade de sua utilização em agricultura totalmente dependente de chuva e agricultura irrigada.bitstream/item/179575/1/FL-07749.pd

Propriedades físicas e hídricas do solo fundamentais para dimensionamento e operação de projetos de irrigação.

Os solos irrigados geralmente sao de zonas aridas e semi-aridas e o sucesso da irrigação depende em grande parte da qualidade do solo. Para um manejo racional e eficiente de irrigação, precisa-se conhecer certas relações que se processam entre o solo, a água do solo, a atmosfera e as plantas. O não reconhecimento da importância destas relações como também a sua nao utilização nas praticas irrigacionistas, torna difícil a atividade tanto para o técnico de irrigaçao como para o agricultor.bitstream/item/184560/1/FL-02947.pdfTrabalho apresentado no I Curso sobre Manejo de Solo e Água em Propriedades Agrícolas no Trópico Semi-Árido, 1982, out. Petrolina

Comparacao de tres sistemas de manejo da irrigacao de tomate industrial em escala semicomercial.

No estudo, efetuou-se a comparacao de dois sistemas de manejo de irrigacao em escala semi-comercial, pra a cultura do tomate, com o manejo de irrigacao, usado pelos agricultores. Nesses dois sistemas de manejo, estabeleceu-se o controle de irrigacao em forma de frequencia. Essa frequencia foi definida em funcao de um Modelo que leva em consideracao dados da evapotranspiracao do tomate, propriedades de retencao e transmissao do solo e producao do tomate em funcao do potencial natricial da agua no solo

Transforming aquatic agricultural systems towards gender equality: a five country review

Aquatic agricultural systems (AAS) are systems in which the annual production dynamics of freshwater and/or coastal ecosystems contribute significantly to total household income. Improving the livelihood security and wellbeing of the estimated 250 million poor people dependent on AAS in Bangladesh, Cambodia, the Philippines, the Solomon Islands and Zambia is the goal of the Worldfish Center-led Consortium Research Program (CRP), “Harnessing the development potential of aquatic agricultural systems for development.” One component expected to contribute to sustainably achieving this goal is enhancing the gender and wider social equity of the social, economic and political systems within which the AAS function. The CRP’s focus on social equity, and particularly gender equity, responds to the limited progress to date in enhancing the inclusiveness of development outcomes through interventions that offer improved availability of resources and technologies without addressing the wider social constraints that marginalized populations face in making use of them. The CRP aims to both offer improved availability and address the wider social constraints in order to determine whether a multi-level approach that engages with individuals, households and communities, as well as the wider social, economic and political contexts in which they function, is more successful in extending development’s benefits to women and other excluded groups. Designing the research in development initiatives to test this hypothesis requires a solid understanding of each CRP country’s social, cultural and economic contexts and of the variations across them. This paper provides an initial input into developing this knowledge, based on a review of literature on agriculture, aquaculture and gender relations within the five focal countries. Before delving into the findings of the literature review, the paper first justifies the expectation that successfully achieving lasting wellbeing improvements for poor women and men dependent on AAS rests in part on advances in gender equity, and in light of this justification, presents the AAS CRP’s conceptual frame

Probing Lepton Flavor Violation at Future Colliders

Supersymmetric theories with significant lepton flavor violation have $\tilde{e}$ and $\tilde{\mu}$ nearly degenerate. In this case, pair production of $\tilde{e}^+ \tilde{e}^-$ and $\tilde{\mu}^+ \tilde{\mu}^-$ at LEPII and at the Next Linear Collider leads to the phenomenon of slepton oscillations, which is analogous to neutrino oscillations. The reach in $\Delta m^2$ and $\sin^2 2 \theta$ gives a probe of lepton flavor violation which is significantly more powerful than the current bounds from rare processes, such as $\mu \to e\gamma$. Polarizable $e^-$ beams and the $e^-e^-$ mode at the NLC are found to be promising options.Comment: 10 pages, 3 figures, RevTeX, minor corrections, published versio