3,749 research outputs found
Synthesis of monoalkylated calix[4]arenes via direct alkylation
A new one-step procedure for the synthesis of monoalkylated calix[4]arenes is presented. Reaction of calix[4]arene 1a or 1b with 1.2 equivalent of a weak base (K2CO3 in MeCN or CsF in DMF) and excess of alkylating agent affords the monoalkylated calix[4]arenes in moderate to good yield
Divergência genética em genótipos de girassol.
Uma investigação sobre a diversidade genética em 15 genótipos de girassol, por meio de 12 características agronômicas, foi implementada no Instituto Agronômico de Campinas, Brasil. Análises de variância univariada e multivariada revelaram diferenças entre os genótipos. A distância generalizada de Mahalanobis indicou um alto grau de divergência genética. Os genótipos foram agrupados em três grupos. As características início do florescimento, 50% do florescimento, número de folhas e altura da inserção do capítulo contribuíram com grande parte da divergência genética observada. Por meio desses resultados, é possível identificar materiais divergentes e complementares para o desenvolvimento de novos cultivares superiores
Relations between the United States of America and Italy in the post-Cold War period: a defense-industrial perspective
This article analyzes U.S.-Italian relations after 1989 from a defence-industrial perspective. It argues that the concentration and internationalization of the Italian defence industry, particularly through the creation of Finmeccanica, influenced bilateral relations by introducing a new element into defence industrial cooperation between the two countries. Military procurement programs involving American and Italian governments and industries, based on several memorandums of understanding, have become an important component of transatlantic relations. In turn, these programs are influenced by the broader military and political relations between the United States and Italy, which have been particularly intense regarding Italy’s contribution to U.S.-led crisis management operations in Europe, Central Asia and the greater Mediterranean. The paper argues that there is a two-way relationship between defence industrial cooperation and politico-military cooperation.Cet article présente une analyse des relations entre les États-Unis d’Amérique et l’Italie depuis 1989 vues sous l’angle de l’industrie de la défense. La concentration et le développement international de l’industrie italienne de la défense, avec en particulier la création de Finmeccanica, a fait évoluer la relation bilatérale en introduisant un élément nouveau dans la coopération industrielle entre les États-Unis d’Amérique et l’Italie. Les programmes de fournitures militaires auxquels participent les gouvernements et industriels américains et italiens se basent sur plusieurs accords-cadres et sont devenus un élément important des relations transatlantiques. Cet élément est également influencé par les relations bilatérales militaires et politiques. Il s’agit de relations intenses marquées par la participation de l’Italie à des opérations de gestion de crise en Europe, Asie centrale ainsi que dans la région méditerranéenne. En conclusion, l’article montre comment s’articule une relation à double sens dans laquelle la dimension de coopération dans l’industrie de la défense et celle politico-militaire se correspondent
Sunflower and peanut emergency : initial development under sugarcane mulch.
The research aimed to evaluate the effect of residual sugarcane mulch on sunflower and peanut plant emergence and initial development. Vases of 4.0 L were disposed in a randomized experimental blocks design, with four replications, in a factorial arrangement of five mulch amounts and three cultivars of each crop. The mulch treatments consisted of four increasing amounts (5, 10, 15 e 20 t ha-1) and a tester with no mulch. The sunflower cultivars were the varieties IAC-iarama and Catissol and the hybrid H-358; the peanut cultivars were IAC-Caiapó, Runner 886 and Tatu. The speed emergency index and final percentage, the plant height and shoot dry mass were evaluated. The presence of different levels of sugarcane mulch negatively influences the emergency and initial plant development mainly in peanut but also in sunflower. The negative effects are stronger especially for the runner type of peanut cultivars, while cultivar Tatu was less influenced by the mulch thickness
The Heavy Photon Search beamline and its performance
The Heavy Photon Search (HPS) is an experiment to search for a hidden sector
photon, aka a heavy photon or dark photon, in fixed target electroproduction at
the Thomas Jefferson National Accelerator Facility (JLab). The HPS experiment
searches for the ee decay of the heavy photon with bump hunt and
detached vertex strategies using a compact, large acceptance forward
spectrometer, consisting of a silicon microstrip detector (SVT) for tracking
and vertexing, and a PbWO electromagnetic calorimeter for energy
measurement and fast triggering. To achieve large acceptance and good vertexing
resolution, the first layer of silicon detectors is placed just 10 cm
downstream of the target with the sensor edges only 500 m above and below
the beam. Placing the SVT in such close proximity to the beam puts stringent
requirements on the beam profile and beam position stability. As part of an
approved engineering run, HPS took data in 2015 and 2016 at 1.05 GeV and 2.3
GeV beam energies, respectively. This paper describes the beam line and its
performance during that data taking
Duration of quarantine in hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection: a question needing an answer
Probing the nucleon structure with CLAS
An overview of recent results with CLAS is presented with emphasis on nucleon
resonance studies, nucleon spin structure, and generalized parton
distributions.Comment: Plenary talk presented at NSTAR 2007, Bonn, German
The Jlab Upgrade - Studies of the Nucleon with CLAS12
An overview is presented on the program to study the nucleon structure at the
12 GeV JLab upgrade using the CLAS12 detector. The focus is on deeply virtual
exclusive processes to access the generalized parton distributions,
semni-inclusive processes to study transverse momentum dependent distribution
functions, and inclusive spin structure functions and resonance transition form
factors at high Q^2 and with high precision.Comment: 7 pages, 12 figures, NSTAR 2007 conference, Bonn, September 5-8, 200
Distribution, abundance and biological features of anglerfish (Lophius piscatorius and Lophius budegassa) (Osteichthyes: Lophiiformes) in the Mediterranean Sea
The distribution and biological features of anglerfish (Lophius piscatorius and L. budegassa) in the Mediterranean Sea were analysed from trawl surveys data (MEDITS project, years 1994-1999). The above-mentioned species were widely distributed in the Mediterranean, but differences in abundance were found according to geographic sectors and depths. Most of the collected specimens belonged to the first length cohorts and length distributions also differed at macroarea levels. Mean sizes at female sexual maturity were estimated at 68.5 cm and 66.2 cm total length, respectively for L. piscatorius and L. budegassaPublicado
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