On the 2D Dirac oscillator in the presence of vector and scalar potentials in the cosmic string spacetime in the context of spin and pseudospin symmetries

The Dirac equation with both scalar and vector couplings describing the dynamics of a two-dimensional Dirac oscillator in the cosmic string spacetime is considered. We derive the Dirac-Pauli equation and solve it in the limit of the spin and the pseudo-spin symmetries. We analyze the presence of cylindrical symmetric scalar potentials which allows us to provide analytic solutions for the resultant field equation. By using an appropriate ansatz, we find that the radial equation is a biconfluent Heun-like differential equation. The solution of this equation provides us with more than one expression for the energy eigenvalues of the oscillator. We investigate these energies and find that there is a quantum condition between them. We study this condition in detail and find that it requires the fixation of one of the physical parameters involved in the problem. Expressions for the energy of the oscillator are obtained for some values of the quantum number $n$. Some particular cases which lead to known physical systems are also addressed.Comment: 15 pages, 8 figures, matches published versio

Evidence of spontaneous spin polarized transport in magnetic nanowires

The exploitation of the spin in charge-based systems is opening revolutionary opportunities for device architecture. Surprisingly, room temperature electrical transport through magnetic nanowires is still an unresolved issue. Here, we show that ferromagnetic (Co) suspended atom chains spontaneously display an electron transport of half a conductance quantum, as expected for a fully polarized conduction channel. Similar behavior has been observed for Pd (a quasi-magnetic 4d metal) and Pt (a non-magnetic 5d metal). These results suggest that the nanowire low dimensionality reinforces or induces magnetic behavior, lifting off spin degeneracy even at room temperature and zero external magnetic field.Comment: 4 pages, 3 eps fig

Moisture effects on the bond strength of FRP-masonry elements

Moisture exposure has been observed to be one of the degrading environmental agents which affects the durability of the FRP-strengthened elements by changing the constituent material or bond properties. This paper presents the experimental investigation on the effects of moisture on the pull-off bond strength of GFRP-strengthened brick specimens. The specimens have been prepared following the wet lay-up procedure and exposed to constant moisture level of 100% R.H. at 23̊C for 8 weeks. The degradation in the bond performance has been investigated by performing pull-off tests on the conditioned specimens after 4 and 8 weeks of exposure. The reversibility of the bond degradation has been also studied by storing some specimens in the laboratory conditions for 1 week after conditioning and before performing the pull-off tests. Comparative analysis has been performed and the main results are presented and discussed

Primary pleural myxoid liposarcoma: case report and literature review

Myxoid liposarcoma is a histological subtype of malignant tumors within the group of sarcomas. It is more common in men between the ages of 40 and 50 years. Diagnosis is difficult because they are usually asymptomatic lesions, computed tomography (CT) scan and magnetic resonance are the studies of choice. The gold of treatment is surgical resection with free margins. Chemotherapy and radiotherapy have shown a good response. A 46-year-old male was detected incidental mediastinal lesion by radiography, CT scan showed a hypodense lesion in the right hemithorax that extended to the left hemithorax, infiltrating the diaphragm and large vessels. The patient underwent an exploratory thoracotomy, finding a multilobulated tumor and mucous content approximately 600 ml, adjacent structures were infiltrated, so complete resection was not possible. Subsequently, adjuvant chemotherapy given. The histopathological diagnosis was myxoid liposarcoma. Myxoid liposarcoma is a malignant lesion. The primary pleural origin is rare. Surgical resection with free margins has a good prognosis. Due to advanced disease, a complete resection in this case was not possible, that compromised the patient prognosis

Oxidative stress modulates the expression of VEGF isoforms in the diabetic retina

Funding: This work was supported by the Portuguese Foundation for Science and Technology (FCT) with individual grants to S. Simão (SFRH/ BPD/78404/2011), D. Bitoque (SFRH/BD/52424/2013), S. Calado (SFRH/BD/76873/2011), GA Silva (EXPL-BIM-MEC-1433-2013, PIRG05-GA-2009-249314–EyeSee). FCT Research Center Grant UID/ BIM/04773/2013 CBMR 1334.publishersversionpublishe

Banana peel and grape stalk: potential of valorization through the evaluation of chemical composition and physical-chemical properties

CHISA 2008 - 18th International Congress of Chemical and Process Engineering (CD-ROM of Full Texts)Bioconversion of food processing residues (agr o-based industrial residues) in valuable products has been receiving an increasing attention in the last years. In fact, the main problem experienced by agro-based industries in several c ountries is the management of their residues. As a consequence, many research centers and government departments are preparing scientific strategies in order to develop biotechnological processes capable of transforming these residues in new bio-products or as sources of other chemicals. Most of these agro-industrial residues are lignocellulosic materials constituted basically of cellulose, hemicelluloses, and lignin. In particular, banana production is one of the main economic resources of several regions in many countries, an important crop in the tropical and sub- tropical regions and one of the most consumed fruits in the world. Grapes are other of the world’s largest fruit crops, mainly grown for direct consumption, grape juice and wine- making processes. These agricultural/industrial activities generate large amounts of residues such as banana fruit peel and grape stalk. Taking in consideration these facts, it is fundamental to know their chemical composition and physical-chemical properties, in order to evaluate perspectives of applications and improvement of procedures towards an efficient utilization of these residues. For this reason, following hydrolysis, the residues obtained were analyzed by HPLC, FTIR, TGA and DSC. Preliminary results indicate the attractiveness of these materials for further applications due to their chemical composition and physical-chemical properties: glucan and xylan contents of banana peel are 23.2 ± 0.2% and 18.9 ± 0.5%, respectively, while grape stalk contains 26.5 ± 1.5% and 16.8 ± 0.4%, respectively. These results are in agreement with those obtained with some other agro-industrial residues. These approaches offer several advantages, since the several fractions obtained from the hydrolysis of these annually produced materials can be applied as raw-materials to reduce the existence of environmentally hazardous situations and/or to increase the supply of energy or chemicals produced from renewable resourcesFCT(Portugal), FAPESP(Brazil) and CAPES/GRICES(Brazil/Portugal)info:eu-repo/semantics/publishedVersio

A new strategy for using banana as an ingredient in the brewing process

Beer is a traditionally fermented beverage made from malted grains of barley, hops, yeast, and water, while banana is an important food crop cultivated widely in tropical and subtropical areas and is one of the major fruits in Brazil. Besides, the banana is also very favorable to food industry (e.g. fermented beverages) due to its rich content on soluble solids, presence of minerals, and providing low acidity. In this context, the objective of this work was to evaluate a new strategy for using banana as adjunct to increase the fermentable sugars and to supply a specific aroma in pilot-plant brewing experiments. For this, static fermentations were conducted in a 180 L cylindrical-conical reactor using 140 L as working volume. Addition of banana was evaluated when changing the concentration of the wort from 10 to 12 ºP and from 10 to 13.5 ºP (ºP is the weight of the extract or the sugar equivalent in 100 g solution, at 20 ºC) and fermented under a constant temperature of 10 and 12.5 ºC, respectively. The results showed that the increment in the initial sugar concentration (12 to 13.5 ºP, due to the use of banana juice as adjunct), and in the temperature (10 to 12.5 ºC), increased approximately 17% the ethanol productivity. Thus, it was concluded that by using of simple preparation techniques of banana juice, banana can be used as adjunct in brewing processes, helping in the development of new products as well as in the elaboration of more concentrated worts when compared the traditional brewing worts.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Malteria do ValeCorn Products BrasilWallerstein Industrial e ComercialDiverseyLever (Brazil)Fundação para a Ciência e a Tecnologia (FCT)CAPES/GRICES (Brazil/Portugal

Hemispheric asymmetry in the sunspot cycle as a nonextensive phenomenon

The appearance of dark sunspots over the solar photosphere is not considered to be symmetric between the northern and southern hemispheres. Among the different conclusions obtained by several authors, we can point out that the North-South asymmetry is a real and systematic phenomenon and is not due to random variability. In the present work, we selected the sunspot area data of a sample of 13 solar cycles divided by hemisphere extracted from the Marshall Space Flight Centre (MSFC) database to investigate the behavior of probability distributions using an out-of-equilibrium statistical model a.k.a non-extensive statistical mechanics. Based on this statistical framework, we obtained that the non-extensive entropic parameter $q$ has a semi-sinusoidal variation with a period of $\sim$22 year (Hale cycle). Among the most important results, we can highlight that the asymmetry index $q(A)$ revealed the dominance of the northern hemisphere against the southern one. Thus, we concluded that the parameter $q(A)$ can be considered an effective measure for diagnosing long-term variations of the solar dynamo. Finally, our study opens a new approach to investigating solar variability from the nonextensive perspective.Comment: 17 pages, 2 tables and 5 figures. Submitted to Solar Physic