Distribución espacial de leguminosas en relación con el arbolado

A study was made of tree canopy influence on spatial distribution of leguminosae species and some soil variables in grassland communities. Besides the differentiation according to the tree species, it is possible to establish groups of samples according to their distance frorn the tree trunk. The greatest influence of canopy on vegetation and soil variables has been detected in the samples taken on the northern side of the trees.Se estudia la incidencia del arbolado sobre la distribución espacial de especies pertenecientes a la familia de las leguminosas y sobre algunas variables edáficas, en comunidades de pastizal adehesado. Aparte de la diferenciación atribuible a la especie arbórea, en todos los casos es posible el establecimiento de grupos de acuerdo con la distancia al tronco. La mayor influencia del arbolado se detecta en orientación norte, tanto en lo que se refiere a la vegetación como a las variables edíficas

Topological Hunds rules and the electronic properties of a triple lateral quantum dot molecule

We analyze theoretically and experimentally the electronic structure and charging diagram of three coupled lateral quantum dots filled with electrons. Using the Hubbard model and real-space exact diagonalization techniques we show that the electronic properties of this artificial molecule can be understood using a set of topological Hunds rules. These rules relate the multi-electron energy levels to spin and the inter-dot tunneling $t$, and control charging energies. We map out the charging diagram for up to N=6 electrons and predict a spin-polarized phase for two holes. The theoretical charging diagram is compared with the measured charging diagram of the gated triple-dot device.Comment: 31 pages, 7 figures, accepted to March 15, 2007 issue of Phys. Rev. B, vol. 7

BiFC and CRISPR-dCpf1, a new tool to study DNA-proteins interactions

Motivation: CRISPR based systems allow directing a protein (Cpf1) to specific genome regions guided by a small RNA molecule (known as sgRNA), which leads Cpf1 to a specific DNA sequence. We are using this system in combination with the Bimolecular fluorescence complementation (BiFC) to monitor DNA-Protein interactions. This new system consists in tagging a fragment of YFP to the endonuclease dead dCpf1 which, by the action of the sgRNA previously designed, will still be guided to the specific DNA sequence without making the dsb. On the other hand, another native know to interact with the same region is tagged to the other YFP fragment. The interaction between the protein and that specific sequence would allow the association of the fragments produce a bimolecular fluorescent complex. This proof-of-principle to monitor DNA-Protein (and eventually DNA-DNA) interactions will allow genome dinamics studies in vivo. Methods: We will use a dead version of the CRISPR based Cpf1 nuclease in combination with BiFC. We will obtain dCpf1 using a directed mutagenesis mechanism by PCR from the pMZCpf1. To validate the system we will first direct the dCpf1-YFP fusion to the centromeres, as a control region of the genome. This fusion will be created by overlapping PCR and also we will put it under the regulation of a medium strength promotor (nmt41), flanked by both halves of the Hygromycin resistance gene. We will integrate this cassette into a Hygromicin resistant strain by homologous recombination. We will obtain the specific sgRNA, which will guide Cpf1-YFP to the centromeres. To show proper localization we will use a cnp1-mCherry (centromeric protein) to assess co-localization. Once validated that level, we will split YFP by tagging the two proteins (dCpf1 and Cnp1) to validate biFC system.Conclusions: The development of this system provides a great tool that would enable observing DNA- proteins interactions with a huge precision. With regards to the future, several sgRNAs could be generated to study interactions of proteins with multiple sequences of a genome.This would allow to study genomic loci dynamics and nuclear topology in vivo

Some Probabilistic Results in a Bisexual Branching Process with Immigration

2000 Mathematics Subject Classification: 60J80.A bisexual branching process with immigration of females and males is introduced. It is allowed, in each generation, that the mating function and the probability distributions associated to the offspring and the immigration may change depending on the number of progenitor couples. Relationships among the probability generating functions involved in the model and some transition and stochastic monotony properties are established.This research has been supported by the Ministerio de Ciencia y Tecnologia and the FEDER through the Plan Nacional de Investigacion Cientifica, Desarrollo e Innovaci on Tecnologica, grant BFM2003-06074

Allocating the surplus induced by cooperation in distribution chains with multiple suppliers and retailers

The coordination of actions and the allocation of profit in supply chains under decentralized control plays an important role in improving the profits of retailers and suppliers in the supply chain. We focus on supply chains under decentralized control in which noncompeting retailers can order from multiple suppliers to replenish their stocks. The goal of the firms in the chain is to maximize their individual profits. As the outcome under decentralized control is inefficient, coordination of actions between cooperating agents can improve individual profits. Cooperative game theory is used to analyze cooperation between agents. We introduce multi-retailer-supplier games and show that agents can always achieve an optimal profit by cooperating and forming the grand coalition. Moreover, we show that there will always be stable allocations of total profit among the firms which cannot be improved by any coalition. In addition, we propose and characterize a stable allocation of the total surplus induced by cooperation.We gratefully acknowledge financial support from the Ministerio de Ciencia, Spain, Innovación y Universidades (MCIU/AEI/FEDER, UE) through project PGC2018-097965-B-I00, PID2020-114594GB–{C21,C22}, PID2022-137211NB-100; and Fundación BBVA: project NetmeetData (Ayudas Fundación BBVA a equipos de investigación científica 2019), Spain; and by Generalitat Valenciana, Spain through project PROMETEO/2021/063

Unitary Owen Points in Cooperative Lot-Sizing Models with Backlogging

This paper analyzes cost sharing in uncapacitated lot-sizing models with backlogging and heterogeneous costs. It is assumed that several firms participate in a consortium aiming at satisfying their demand over the planning horizon with minimal operating cost. Each individual firm has its own ordering channel and holding technology, but cooperation with other firms consists in sharing that information. Therefore, the firms that cooperate can use the best ordering channels and holding technology among members of the consortium. This mode of cooperation is stable. in that allocations of the overall operating cost exist, so that no group of agents benefit from leaving the consortium. Our contribution in the current paper is to present a new family of cost sharing allocations with good properties for enforcing cooperation: the unitary Owen points. Necessary and sufficient conditions are provided for the unitary Owen points to belong to the core of the cooperative game. In addition, we provide empirical evidence, through simulation, showing that, in randomly-generated situations, the above condition is fulfilled in 99% of the cases. Additionally, a relationship between lot-sizing games and a certain family of production-inventory games, through Owen’s points of the latter, is described. This interesting relationship enables easily constructing a variety of coalitionally stable allocations for cooperative lot-sizing models.The research authors is supported from Spain’s Ministerio de Ciencia, Innovación y Universidades (MCIU), from the Agencia Estatal de Investigación (AEI) and from the Fondo Europeo de Desarrollo Regional (FEDER) under the projects MTM2016-74983-C02-01 and PGC2018-097965-B-I00. The research of the third author is also partially supported from projects FEDER-US-1256951, CEI-3-FQM331 and NetmeetData: Ayudas Fundación BBVA a equipos de investigación científica 2019

Dynamic realization games in newsvendor inventory centralization

Consider a set N of n (> 1) stores with single-item and single-period nondeterministic demands like in a classic newsvendor setting with holding and penalty costs only. Assume a risk-pooling single-warehouse centralized inventory ordering option. Allocation of costs in the centralized inventory ordering corresponds to modelling it as a cooperative cost game whose players are the stores. It has been shown that when holding and penalty costs are identical for all subsets of stores, the game based on optimal expected costs has a non empty core (Hartman et al. 2000, Games Econ Behav 31:26–49; Muller et al. 2002, Games Econ Behav 38:118–126). In this paper we examine a related inventory centralization game based on demand realizations that has, in general, an empty core even with identical penalty and holding costs (Hartman and Dror 2005, IIE Trans Scheduling Logistics 37:93–107). We propose a repeated cost allocation scheme for dynamic realization games based on allocation processes introduced by Lehrer (2002a, Int J Game Theor 31:341–351). We prove that the cost subsequences of the dynamic realization game process, based on Lehrer’s rules, converge almost surely to either a least square value or the core of the expected game. We extend the above results to more general dynamic cost games and relax the independence hypothesis of the sequence of players’ demands at different stages