Estudo químico e avaliação do potencial moluscicida da espécie vegetal serjania glabrata kunth (sapindaceae)

The present works was aimed at the chemical study and evaluation of molluscicidal potential of the vegetable specie Serjania glabrata Kunth, which belongs to the family Sapindaceae. This family is characterized by the accumulation of quebrachitol and triterpenic saponins (often toxic) in their parenchymatous tissues, and their seeds an unusual class of composts, the cyanolipids. The plant was separated into leaves, twigs and seeds and subjected to different methods of extraction and purification. The fractionation of hexane extract from the leaves in different solvents using chromatography techniques resulted in the isolation of two mixtures of unsaturated hydrocarbons and triterpene ß-amyrin. The amino acid N-methyl-trans-4-hydroxyl-Lproline was isolated from the ethanolic extract of branches after fractionation in column chromatography. With the hexane extract of the seeds was isolated a cyanolipid type I, the 1-cyano-2-hydroymethylprop-2-en-1-ol-diester. It was also employed the methodology of precipitation saponins and subsequent dialysis of the precipitate of the ethanolic extract of the seeds. Through the column chromatography fractionation was isolated the substance quebrachitol. The evaluation of the molluscicidal potential indicated the hexane extracts of branches as active and hexane extract of the seeds as very active, with the LC50 value of 137,6 µg.mL-1 and 28,3 µg.mL-1, respectively.O presente trabalho teve como objetivo o estudo químico e a avaliação do potencial moluscicida da espécie vegetal Serjania glabrata Kunth, pertence à família Sapindaceae. Esta família caracteriza-se pelo acúmulo de quebrachitol e saponinas triterpênicas (geralmente tóxicas) em seus tecidos parequimáticos, e nas suas sementes uma classe incomum de compostos, os cianolipídios. A planta foi separada em folhas, galhos e sementes e submetida a diferentes metodologias de extração e purificação. O fracionamento extrato hexânico das folhas em diferentes solventes utilizando técnicas cromatográficas resultou no isolamento de duas misturas de hidrocarbonetos insaturados e do triterpeno ß-amirina. O aminoácido n-metil-trans-4-hidroxil-L-prolina foi isolado do extrato etanólico dos galhos após fracionamento em coluna cromatográfica. Do extrato hexâncio das sementes foi isolado um cianolipídio de tipo I, o 1-ciano-2-hidroximetilpropil-2-en-1-ol-diéster. Também foi empregada, a metodologia de precipitação de saponinas e posterior diálise do precipitado com o extrato etanólico das sementes. Do fracionamento em coluna cromatográfica foi isolada a substância quebrachitol. A avaliação do potencial moluscicida dos extratos indicou o hexânico dos galhos como sendo ativo e hexânico das sementes como sendo muito ativo, com valor de LC50 de 137,6 µg.mL-1 e 28,3 µg.mL-1, respectivamente.xiii, 91

Dynamical Formation of Kerr Black Holes with Synchronized Hair: An Analytic Model

East and Pretorius have successfully evolved, using fully nonlinear numerical simulations, the superradiant instability of the Kerr black hole (BH) triggered by a massive, complex vector field. Evolutions terminate in stationary states of a vector field condensate synchronized with a rotating BH horizon. We show that these end points are fundamental states of Kerr BHs with synchronized Proca hair. Motivated by the “experimental data” from these simulations, we suggest a universal (i.e., field-spin independent), analytic model for the subset of BHs with synchronized hair that possess a quasi-Kerr horizon, applicable in the weak hair regime. Comparing this model with fully nonlinear numerical solutions of BHs with a synchronized scalar or Proca hair, we show that the model is accurate for hairy BHs that may emerge dynamically from superradiance, whose domain we identify

Investment Treaties, Offshore Finance, and the Resource Curse

Questions of how best to understand offshore financial centers (“OFCs”)—countries that have low or zero tax rates, strong banking secrecy regulation, and easy-to-form legal entities—and what, if anything, the international community should do about them remain fixed on the agenda of national and international discourse. This Essay seeks to provide a new theoretical perspective on tax havens and applies this perspective to the cross-border legal regimes that govern international investment. This new analytical framework sees offshore financial centers as countries that are victims of the “resource curse,” as that term is described in economic development literature. Often physically small, isolated islands with scant natural resources, OFCs lack any true commodity to exchange in the global marketplace. As a result, OFCs have transformed their legal systems into a resource, “selling” their favorable laws to businesses and individuals in exchange for corporate registration costs and money management fees as a means of gaining revenue for the state and its inhabitants. Applying this framework to international investment law yields new insights into why countries enter into bilateral investment treaties and how the true social costs of international investment should be understood

The neutral kaon mixing parameter B_K from unquenched mixed-action lattice QCD

We calculate the neutral kaon mixing parameter B_K in unquenched lattice QCD using asqtad-improved staggered sea quarks and domain-wall valence quarks. We use the "2+1" flavor gauge configurations generated by the MILC Collaboration, and simulate with multiple valence and sea quark masses at two lattice spacings of a ~ 0.12 fm and a ~ 0.09 fm. We match the lattice determination of B_K to the continuum value using the nonperturbative method of Rome-Southampton, and extrapolate B_K to the continuum and physical quark masses using mixed action chiral perturbation theory. The "mixed-action" method enables us to control all sources of systematic uncertainty and therefore to precisely determine B_K; we find a value of B_K^{MSbar, NDR}(2 GeV) = 0.527(6)(20), where the first error is statistical and the second is systematic.Comment: 72 pages, 26 figures, 6 tables, uses RevTeX. Discussion about chiral/continuum extrapolation expanded for clarification, references added, conclusions remain unchanged, version published in Phys. Rev.

Heat recovery subsystem and overall system integration of fuel cell on-site integrated energy systems

The best HVAC (heating, ventilating and air conditioning) subsystem to interface with the Engelhard fuel cell system for application in commercial buildings was determined. To accomplish this objective, the effects of several system and site specific parameters on the economic feasibility of fuel cell/HVAC systems were investigated. An energy flow diagram of a fuel cell/HVAC system is shown. The fuel cell system provides electricity for an electric water chiller and for domestic electric needs. Supplemental electricity is purchased from the utility if needed. An excess of electricity generated by the fuel cell system can be sold to the utility. The fuel cell system also provides thermal energy which can be used for absorption cooling, space heating and domestic hot water. Thermal storage can be incorporated into the system. Thermal energy is also provided by an auxiliary boiler if needed to supplement the fuel cell system output. Fuel cell/HVAC systems were analyzed with the TRACE computer program

Police Secrecy Exceptionalism

Every state has a set of transparency statutes that bind state and local governments. In theory, these statutes apply with equal force to every agency. Yet, in practice, law enforcement agencies enjoy a wide variety of unique secrecy protections denied to other government entities. Legislators write police-specific exemptions into public records laws. Judges develop procedural approaches that they apply exclusively to police and prosecutorial records. Police departments claim special secrecy protections from the bottom up. This Article maps the legal infrastructure of police-records secrecy. It draws upon the text of the public records statutes in all fifty states, along with case law and public records datasets, to illuminate the ways that judges, legislators, and police officers use transparency statutes to shield law enforcement agencies from public view. It argues that this robust web of police secrecy protections operates as a kind of police secrecy exceptionalism, analogous in some ways to the exceptional protections granted to national security secrets in the federal context. The Article then examines the doctrinal and policy-oriented underpinnings of this exceptional treatment, finding that these arguments generally fall into one of three buckets: protection against circumvention of the law, protection of citizen or police officer privacy, and preservation of the effectiveness or efficiency of policing. It concludes that none of these defenses justify the extraordinary informational protections currently extended to law enforcement agencies. Moreover, these secrecy protections impose substantial harms. By excavating these overlooked mechanisms of police secrecy, the Article illuminates new avenues of legal reform