Identification and Dynamical Properties of Asteroid Families

Asteroids formed in a dynamically quiescent disk but their orbits became gravitationally stirred enough by Jupiter to lead to high-speed collisions. As a result, many dozen large asteroids have been disrupted by impacts over the age of the Solar System, producing groups of fragments known as asteroid families. Here we explain how the asteroid families are identified, review their current inventory, and discuss how they can be used to get insights into long-term dynamics of main belt asteroids. Electronic tables of the membership for 122 notable families are reported on the Planetary Data System node.Comment: Asteroids IV chapte

Noncanonical inflammasomes: caspase-11 activation and effector mechanisms

Inflammasomes are cytosolic, multiprotein complexes assembled by members of the NOD-like receptor (NLR) and PYHIN protein families in response to pathogen-associated molecular patterns (PAMPs) and danger signals, and serve as activation platforms for caspase-1. Recently, a new noncanonical inflammasome pathway has been described that activates caspase-11, an understudied pro-inflammatory caspase. Despite new insights into the signaling events that control caspase-11 activation, a number of unanswered questions remain..

Innate Immune Recognition of Francisella Tularensis: Activation of Type-I Interferons and the Inflammasome

Francisella tularensis is an intracellular pathogen that can cause severe disease in a wide range of mammalian hosts. Primarily residing in host macrophages, F. tularensis escapes phagosomal degradation, and replicates in the macrophage cytosol. The macrophage uses a series of pattern recognition receptors to detect conserved microbial molecules from invading pathogens, and initiates an appropriate host response. In the cytosol, F. tularensis is recognized by the inflammasome, a multiprotein complex responsible for the activation of the cysteine protease caspase-1. Caspase-1 activation leads to processing and release of proinflammatory cytokines and host cell death. Here we review recent work on the molecular mechanisms of inflammasome activation by F. tularensis, and its consequences both in vitro and in vivo. Finally, we discuss the coordination between the inflammasome and other cytosolic host responses, and the evidence for F. tularensis virulence factors that suppress inflammasome activation

Applying the theory of real options to the optimal timing of timber harvests

Se propone el enfoque de opciones reales como herramienta económico-financiera para la toma de decisiones estratégicas en el sector forestal. En términos de instrumentos financieros, consideraremos en particular una opción exótica conocida como barrier option del tipo knock-in. Suponemos que la proyección del precio de venta promedio de los subproductos sigue un proceso estocástico del tipo Geométrico Browniano, mientras que la producción se determina mediante simulación de un turno forestal. La decisión de talar la masa forestal surge de comparar en cada periodo, el valor de flujo de fondos en cada nodo (FFij(t)) de una rejilla binomial con el valor esperado en el próximo año (X t+1 x e−rΔ t) ). En un ejemplo analizado el criterio tradicional del VAN indica que el mayor valor actual se produce en el instante t = 0 (año 10), mientras que el enfoque de opciones reales arroja que el máximo valor de ejercicio se da en el periodo t = 8 (año 18).We present here a real options approach as a tool for strategic decision-making in the forestry sector. We consider, in particular, an exotic option known as a knock-in barrier option. We use this approach to determine the optimal timing of harvests. The optimal time is determined by comparing at each period, the cash flow corresponding to each node (FFij(t)) in a binomial lattice with the expected value in the next year (X t+1 x e−rΔ t). The traditional NPV indicates, in an hypothetical context analyzed in the paper, that the largest present value is obtained at the tenth year of standing. The real options approach championed here, instead, indicates that the highest value is at the eighteenth year of standing.Fil: Milanesi, Gastón. Universidad Nacional del SurFil: Woitschach, Guillermo B. M.. Universidad Nacional del SurFil: Broz, Diego R.. Universidad Nacional del Su

Comparison of Multiobjective Evolutionary Algorithms for operations scheduling under machine availability constraints

Many of the problems that arise in production systems can be handled with Multi-Objective techniques. One of those problems is that of scheduling operations subject to constraints on the availability of machines and buffer capacity. In this paper we analyze different Evolutionary Multi-Objective Algorithms (MOEAs) for this kind of problems. We consider an experimental framework in which we schedule production operations for four real world Job-Shop contexts using three algorithms, NSGAII, SPEA2 and IBEA. Using two performance indexes, Hypervolume and R2, we found that SPEA2 and IBEA are the most efficient for the tasks at hand. On the other hand IBEA seems to be a better choice of tool since it yields more solutions in the approximate Pareto frontier.Fil: Frutos, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto de Investigaciones Económicas y Sociales del Sur; Argentina;Fil: Méndez, M.. Universidad de Las Palmas de Gran Canaria. Instituto Universitario de Sistemas Inteligentes y Aplicaciones Numéricas en Ingeniería : España;Fil: Tohme, Fernando Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto de Investigaciones Económicas y Sociales del Sur; Argentina;Fil: Broz, Diego Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto de Investigaciones Económicas y Sociales del Sur; Argentina

Revising the age for the Baptistina asteroid family using WISE/NEOWISE data

We have used numerical routines to model the evolution of a simulated Baptistina family to constrain its age in light of new measurements of the diameters and albedos of family members from the Wide-field Infrared Survey Explorer. We also investigate the effect of varying the assumed physical and orbital parameters on the best-fitting age. We find that the physically allowed range of assumed values for the density and thermal conductivity induces a large uncertainty in the rate of evolution. When realistic uncertainties in the family members' physical parameters are taken into account we find the best-fitting age can fall anywhere in the range of 140-320 Myr. Without more information on the physical properties of the family members it is difficult to place a more firm constraint on Baptistina's age.Comment: 27 pages, 16 figures, accepted to Ap

Arabidopsis Tetraspanins Are Confined to Discrete Expression Domains and Cell Types in Reproductive Tissues and Form Homo- and Heterodimers When Expressed in Yeast

Tetraspanins are evolutionary conserved transmembrane proteins present in all multicellular organisms. In animals, they are known to act as central organizers of membrane complexes and thought to facilitate diverse biological processes, such as cell proliferation, movement, adhesion, and fusion. The genome of Arabidopsis (Arabidopsis thaliana) encodes 17 members of the tetraspanin family; however, little is known about their functions in plant development. Here, we analyzed their phylogeny, protein topology, and domain structure and surveyed their expression and localization patterns in reproductive tissues. We show that, despite their low sequence identity with metazoan tetraspanins, plant tetraspanins display the typical structural topology and most signature features of tetraspanins in other multicellular organisms. Arabidopsis tetraspanins are expressed in diverse tissue domains or cell types in reproductive tissues, and some accumulate at the highest levels in response to pollination in the transmitting tract and stigma, male and female gametophytes and gametes. Arabidopsis tetraspanins are preferentially targeted to the plasma membrane, and they variously associate with specialized membrane domains, in a polarized fashion, to intercellular contacts or plasmodesmata. A membrane-based yeast (Saccharomyces cerevisiae) two-hybrid system established that tetraspanins can physically interact, forming homo- and heterodimer complexes. These results, together with a likely genetic redundancy, suggest that, similar to their metazoan counterparts, plant tetraspanins might be involved in facilitating intercellular communication, whose functions might be determined by the composition of tetraspanin complexes and their binding partners at the cell surface of specific cell types.Marie Curie International Reintegration grant: (no. IRG–256602), U.S. Department of Agriculture-Agricultural Research Service Current Research Information System grant: (5335–21000–030–00D), Fundação Ciência e Tecnologia Postdoctoral Fellowship: (SFRH/BPD/43584/2008), China Scholarship Council fellowship, UC-Berkeley College of Natural Resources SPUR

Kvantitativno određivanje kodeina i aminopirma u smjesama nakon frakcioniranog odjeljivanja pomoću »kalignosta«

U ovom radu ispitana je mogucnost primjene »kalignosta« za odjeljivanje kodein-fosfata i aminopirina u smjesi, u kojoj su zastupane obje supstancije, zatim u smjesi s fenacetinom l kofein-natrijevimbenzoatom. Pri odredivanju potrebnih uvjeta ustanovljeno je, da se frakcioniranim talozenjem najprije istalozi, u alkalnom podrucju (PH 10), kodein-fosfat, a zatim, u slabo kiselom (pH 4-5), aminopirin. Na ovom principu izvrseno je mikroodredivanje kodeinfosfata i aminopirina u spomenutim smjesama

Kvantitativno određivanje kodeina i aminopirma u smjesama nakon frakcioniranog odjeljivanja pomoću »kalignosta«

U ovom radu ispitana je mogucnost primjene »kalignosta« za odjeljivanje kodein-fosfata i aminopirina u smjesi, u kojoj su zastupane obje supstancije, zatim u smjesi s fenacetinom l kofein-natrijevimbenzoatom. Pri odredivanju potrebnih uvjeta ustanovljeno je, da se frakcioniranim talozenjem najprije istalozi, u alkalnom podrucju (PH 10), kodein-fosfat, a zatim, u slabo kiselom (pH 4-5), aminopirin. Na ovom principu izvrseno je mikroodredivanje kodeinfosfata i aminopirina u spomenutim smjesama