The three-body recombination of a condensed Bose gas near a Feshbach resonance

In this paper, we study the three-body recombination rate of a homogeneous dilute Bose gas with a Feshbach resonance at zero temperature. The ground state and excitations of this system are obtained. The three-body recombination in the ground state is due to the break-up of an atom pair in the quantum depletion and the formation of a molecule by an atom from the broken pair and an atom from the condensate. The rate of this process is in good agreement with the experiment on $^{23}$Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.

Casimir-like tunneling-induced electronic forces

We study the quantum forces that act between two nearby conductors due to electronic tunneling. We derive an expression for these forces by calculating the flux of momentum arising from the overlap of evanescent electronic fields. Our result is written in terms of the electronic reflection amplitudes of the conductors and it has the same structure as Lifshitz's formula for the electromagnetically mediated Casimir forces. We evaluate the tunneling force between two semiinfinite conductors and between two thin films separated by an insulating gap. We discuss some applications of our results.Comment: 8 pages, 3 figs, submitted to Proc. of QFEXT'05, to be published in J. Phys.

Air-coupled PMUT at 100 kHz with PZT active layer and residual stresses: Multiphysics model and experimental validation

In this paper a complete Multiphysics modelling via the Finite Element Method (FEM) of an air-coupled Piezoelectric Micromachined Ultrasonic Transducer (PMUT) is described, with its experimental validation related to the mechanical and acoustic responses

Electrochemical Characterization and CO2 Reduction Reaction of a Family of Pyridazine-Bridged Dinuclear Mn(I) Carbonyl Complexes

Three recently synthesized neutral dinuclear carbonyl manganese complexes with the pyridazine bridging ligand, of general formula [Mn2(μ-ER)2(CO)6(μ-pydz)] (pydz = pyridazine; E = O or S; R = methyl or phenyl), have been investigated by cyclic voltammetry in dimethylformamide and acetonitrile both under an inert argon atmosphere and in the presence of carbon dioxide. This family of Mn(I) compounds behaves interestingly at negative potentials in the presence of CO2. Based on this behavior, which is herein discussed, a rather efficient catalytic mechanism for the CO2 reduction reaction toward the generation of CO has been hypothesized

A 20 GHz bright sample for {\delta} > +72{\deg}: I. Catalogue

During 2010-2011, the Medicina 32-m dish hosted the 7-feed 18-26.5 GHz receiver built for the Sardinia Radio Telescope, with the goal to perform its commissioning. This opportunity was exploited to carry out a pilot survey at 20 GHz over the area for {\delta} > + 72.3{\deg}. This paper describes all the phases of the observations, as they were performed using new hardware and software facilities. The map-making and source extraction procedures are illustrated. A customised data reduction tool was used during the follow-up phase, which produced a list of 73 confirmed sources down to a flux density of 115 mJy. The resulting catalogue, here presented, is complete above 200 mJy. Source counts are in agreement with those provided by the AT20G survey. This pilot activity paves the way to a larger project, the K-band Northern Wide Survey (KNoWS), whose final aim is to survey the whole Northern Hemisphere down to a flux limit of 50 mJy (5{\sigma}).Comment: 10 pages, 10 figures. Accepted by MNRA

Controle de plantas voluntárias de soja com herbicidas utilizados em milho.

O presente trabalho teve por objetivo avaliar a eficiência de diversos herbicidas no controle de plantas voluntárias de soja. O experimento foi conduzido em casa de vegetação, onde as unidades experimentais foram compostas de vasos de 10 dm3 de capacidade, dispostos em delineamento inteiramente casualizado em esquema fatorial 2 x 12, com quatro repetições. As cultivares Conquista e Valiosa RR® foram submetidas à aplicação dos herbicidas: atrazine (1.500 g ha-1), tembotrione (100 g ha-1), mesotrione (120 g ha-1), nicosulfuron (40 g ha-1), 2,4-D (670; 1.050 e 1.340 g ha-1), diquat (300 g ha-1), paraquat (400 g ha-1), [paraquat + diuron] (500 + 250 g ha-1) e glyphosate (1.500 g ha-1), além de uma testemunha sem aplicação. A aplicação foi realizada quando as plantas encontravam-se no estádio fenológico V3. Os herbicidas atrazine, glyphosate, [paraquat + diuron] e diquat apresentaram os maiores níveis de controle das plantas voluntárias de soja da variedade Conquista. Os herbicidas atrazine, [paraquat + diuron] e 2,4-D na dose de 1.340 g ha-1 foram os mais eficientes no controle das plantas voluntárias de soja da variedade Valiosa RR®. A suscetibilidade das plantas voluntárias de soja provenientes da variedade convencional (Conquista) e da variedade resistente ao glyphosate (Valiosa RR®) foi variável de acordo com o herbicida aplicado. Control of volunteer soybean plants with herbicides used in corn. This study aimed at evaluating the effectiveness of several herbicides on the control of volunteer soybean plants. The experiment was carried out in a greenhouse, where the experimental units were composed of vessels with 10 dm3 capacity, arranged in a completely randomized design, in a 2 x 12 factorial scheme, with four replications. The cultivars Conquista and Valiosa RR® underwent an application of the herbicides: atrazine (1.500 g ha-1), tembotrione (100 g ha-1), mesotrione (120 g ha-1), nicosulfuron (40 g ha-1), 2.4 D (670; 1,050 and 1,340 g ha-1), diquat (300 g ha-1), paraquat (400 g ha-1), [paraquat + diuron] (500 + 250 g ha-1), and glyphosate (1,500 g ha-1), besides an untreated control. The application was made when the plants were in the phenological stage V3. The herbicides atrazine, glyphosate, [paraquat + diuron] and diquat showed the highest control levels of the volunteer soybean plants of the variety Conquista. The herbicides atrazine, [paraquat + diuron] and 2.4-D at the dose of 1,340 g ha-1 were the most effective ones in controlling volunteer soybean plants of the cultivar Valiosa RR®. The susceptibility of the volunteer soybean plants from the conventional variety (Conquista) and the glyphosate-resistant variety (Valiosa RR®) was variable depending on the applied herbicide

Dietary polyphenols and non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD), which is emerging as a major public health issue worldwide, is characterized by a wide spectrum of liver disorders, ranging from simple fat accumulation in hepatocytes, also known as steatosis, to non-alcoholic steatohepatitis (NASH) and cirrhosis. At present, the pharmacological treatment of NAFLD is still debated and dietary strategies for the prevention and the treatment of this condition are strongly considered. Polyphenols are a group of plant-derived compounds whose anti-inflammatory and antioxidant properties are associated with a low prevalence of metabolic diseases, including obesity, hypertension, and insulin resistance. Since inflammation and oxidative stress are the main risk factors involved in the pathogenesis of NAFLD, recent studies suggest that the consumption of polyphenol-rich diets is involved in the prevention and treatment of NAFLD. However, few clinical trials are available on human subjects with NAFLD. Here, we reviewed the emerging existing evidence on the potential use of polyphenols to treat NAFLD. After introducing the physiopathology of NAFLD, we focused on the most investigated phenolic compounds in the setting of NAFLD and described their potential benefits, starting from basic science studies to animal models and human trials

Weed phytosociological and floristic survey in agricultural areas of southwestern Goiás region.

The use of the Roundup Ready ® technology and the cultivation of a second cropinfluence the floristic composition of weed communities in Brazilian Central-West region cropping systems. This study has aimed to diagnose the dominant weed species in southwestern Goiás in areas of genetically-modified and conventional soybeans, using phytosociological and floristic surveys. Weed sampling was obtained by collecting all the plants present within a 0.5 m hollow frame, randomly thrown 20 times in each of thirty-five agricultural areas in the 2012/2013 harvest. Field survey was carried out in three periods: before desiccation for soybean sowing, before postemergence herbicide in soybean first application and before postemergence herbicide application in late harvest. A total of 525 m2 was inventoried and 3,219 weeds were collected, which included 79 species, 58 genera and 28 families. Families Poaceae, Asteraceae, Euphorbiaceae, Fabaceae, Amaranthaceae, were the most representative in the survey. Species Cenchrus echinatus, Glycine max, Chamaesyce hirta, Commelina benghalensis, and Alternanthera tenella stood out in importance. The RR+millet soybean treatment had the highest number of species (44), while the conventional soybean + sorghum treatment had the lowest number of species (18). The highest number of species was recorded in first sampling period. Treatments conventional soybean + maize and conventional soybean + millet showed higher similarity (70%), while treatments RR soybean + millet and conventional soybean + sorghum showed the least (51%). Species of difficult control were recorded in all cultivation systems analyzed