Interacting fermions and domain wall defects in 2+1 dimensions

We consider a Dirac field in 2+1 dimensions with a domain wall like defect in its mass, minimally coupled to a dynamical Abelian vector field. The mass of the fermionic field is assumed to have just one linear domain wall, which is externally fixed and unaffected by the dynamics. We show that, under some general conditions on the parameters, the localized zero modes predicted by the Callan and Harvey mechanism are stable under the electromagnetic interaction of the fermions

Electrochemical Reactivation of AISI 409 Ferritic Stainless Steel Sheet Welded by Laser Process with application in aeronautical

The susceptibility to sensitization in 409 ferritic stainless steel (FSS) weldments was studied, by means of double loop electrochemical potentiokinetic reactivation test (DL-EPR). After the electrochemical test, the microstructure was analyzed by scanning electron microscopy (SEM) and the presence of elements with dispersive energy of X-rays (EDS), with the X-ray diffraction (XRD) technique they were identified present phases in different welds. Microhardness profiles were employed to evaluate the mechanical properties. With the aim of analyze the effect on the degree of sensitization to welding processes and the base material, a methodological analysis of gas metal arc welding GMAW, gas tungsten arc welding GTAW and LASER welding process was performed. The LASER process generated the highest ratio between the reactivation (Ir) and activation (Ia) current, despite it caused less microstructural change. The higher ratio Ir/Ia is attributed to the lack of penetration in the butt join, showing crevice corrosion. Keywords: 409 Ferritic stainless steel, DL-EPR, GMAW, GTAW, LASER

Transit Timing Observations of the Extrasolar Hot-Neptune Planet GL 436b

Gliese 436 is an M dwarf with a mass of 0.45 Msun and hosts the extrasolar planet GL 436b [3, 6, 7, 2], which is currently the least massive transiting planet with a mass of ~23.17 Mearth [10], and the only planet known to transit an M dwarf. GL 436b represents the first transiting detection of the class of extrasolar planets known as "Hot Neptunes" that have masses within a few times that of Neptune's mass (~17 Mearth) and orbital semimajor axis <0.1 AU about the host star. Unlike most other known transiting extrasolar planets, GL 436b has a high eccentricity (e~0.16). This brings to light a new parameter space for habitability zones of extrasolar planets with host star masses much smaller than typical stars of roughly a solar mass. This unique system is an ideal candidate for orbital perturbation and transit-time variation (TTV) studies to detect smaller, possibly Earth-mass planets in the system. In April 2008 we began a long-term intensive campaign to obtain complete high-precision light curves using the Apache Point Observatory's 3.5-meter telescope, NMSU's 1-meter telescope (located at APO), and Sommers Bausch Observatory's 24" telescope. These light curves are being analyzed together, along with amateur and other professional astronomer observations. Results of our analysis are discussed. Continued measurements over the next few years are needed to determine if additional planets reside in the system, and to study the impact of other manifestations on the light curves, such as star spots and active regions.Comment: 4 pages, 3 figures. To appear in "Proceedings of the 15th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun", 2009, AIP Conference Proceedings vol. 1094, ed. Eric Stempel

Lagrangian-Hamiltonian unified formalism for field theory

The Rusk-Skinner formalism was developed in order to give a geometrical unified formalism for describing mechanical systems. It incorporates all the characteristics of Lagrangian and Hamiltonian descriptions of these systems (including dynamical equations and solutions, constraints, Legendre map, evolution operators, equivalence, etc.). In this work we extend this unified framework to first-order classical field theories, and show how this description comprises the main features of the Lagrangian and Hamiltonian formalisms, both for the regular and singular cases. This formulation is a first step toward further applications in optimal control theory for PDE's.Comment: LaTeX file, 23 pages. Minor changes have been made. References are update

Helichrysum stoechas (L.) Moench reduces body weight gain and modulates mood disorders via inhibition of silent information regulator 1 (SIRT1) by arzanol

The prevalence of obesity is steadily rising, making safe and more efficient anti-obesity treatments an urgent medical need. Growing evidence correlates obesity and comorbidities, including anxiety and depression, with the development of a low-grade inflammation in peripheral and central tissues. We hypothesized that attenuating neuroinflammation might reduce weight gain and improve mood. We investigated the efficacy of a methanolic extract from Helichrysum stoechas (L.) Moench (HSE), well-known for its anti-inflammatory properties, and its main constituent arzanol (AZL). HPLC-ESI-MS2 and HPLC-UV were used to characterize the extract. HSE effects on mood and feeding behavior was assessed in mice. The mechanism of action of HSE and AZL was investigated in hippocampus samples and SH-SY5Y cells by western blotting and immunofluorescence. Oral administration of HSE for 3 weeks limited weight gain with no significant decrease in food intake. HSE produced an anxiolytic-like and antidepressant-like phenotype comparable to diazepam and amitriptyline, respectively, in the absence of locomotor and cognitive impairments and induced neuroprotective effects in glutamate-exposed SH-SY5Y cells. A dose-dependent reduction of SIRT1 expression was detected in SH-SY5Y cells and in hippocampal samples from HSE-treated mice. The inhibition of the SIRT1-FoxO1 pathway was induced in the hypothalamus. Molecular docking studies proposed a mechanism of SIRT1 inhibition by AZL, confirmed by the evaluation of inhibitory effects on SIRT1 enzymatic activity. HSE limited weight gain and comorbidities through an AZL-mediated SIRT1 inhibition. These activities indicate HSE an innovative therapeutic perspective for obesity and associated mood disorders

Iminium Salts of ω-Dithiafulvenylpolyenals: An Easy Entry to the Corresponding Aldehydes and Doubly Proaromatic Nonlinear Optic-phores

A short, high-yielding route to ω-dithiafulvenylpolyenals (1) via the corresponding iminium salts (2) and starting from trimethyl-1,3-dithiolium tetrafluoroborate is reported. The Knoevenagel reactions of either 1 or 2 with isoxazolone-containing acceptors afford merocyanines 7 and 9, in a process that is often accompanied by a vinylene-shortening side reaction. Experimental and theoretical studies reveal that compounds 7 and 9, featuring two proaromatic end groups, are strongly polarized and show good second-order nonlinear optical responses

Technological study of kaolinitic clays from Fms. Escucha and Utrillas to be used in dermo-pharmaceutical products

The present study aims to evaluate five clay samples from different pits in the Teruel province, Spain. While these clays are primarily utilized as raw materials in ceramics, their potential applications in pharmaceutical and cosmetic domains, notably in sun protection and thermal mud products, are under investigation. Characterization of these clays entailed X-ray diffraction, X-ray fluorescence, scanning electron microscopy, pH measurement, analysis of technological properties, rheological assessment, and thermal property evaluation. Furthermore, given the predominant composition of kaolin in most of the samples, their Sun Protection Factor (SPF) in suspensions and physical stability were assessed. The studied samples exhibited varied mineralogical compositions, primarily consisting of kaolinite (70% to 15%), quartz (75% to 5%), and illite (26% to 7%). The pH values of these dispersions closely matched the skin's pH, exhibiting anti-thixotropic behavior at 50% w/w and demonstrating suitable viscosity for skin application. Based on their composition and rheological properties, the samples exhibited potential for use as therapeutic thermal muds. Analyses of cooling kinetics were performed to validate this potential. Results showed that the dispersions systems attained temperatures between 33.89 ◦C and 34.62 ◦C within 20 min (the common application time for thermal muds) and reached 32 ◦C (skin temperature) in 24.3 to 26.22 min, confirming their appropriateness as therapeutic muds. The SPF values of the dispersions varied from 7.46 to 16.65, with the majority of samples showing significant stability during 45 h. Consequently, it can be inferred that most of the studied samples show advantageous characteristics for inclusion in topical formulations, especially in sun protection and thermal mud products

Altered levels of phospholipases C, diacylglycerols, endocannabinoids, and N-acylethanolamines in patients with hereditary angioedema due to FXII mutation

Background: Hereditary angioedema (HAE) is a rare genetic disorder characterized by local, self-limiting edema due to temporary increase in vascular permeability. HAE with normal C1 esterase inhibitor (C1INH) activity includes the form with mutations in the F12 gene encoding for coagulation factor XII (FXII-HAE) causing an overproduction of bradykinin (BK) leading to angioedema attack. BK binding to B2 receptors (BK2R) leads to an activation of phospholipase C (PLC) and subsequent generation of second messengers: diacylglycerols (DAGs) and possibly the endocannabinoids (eCBs), 2-arachidonoylglycerol (2-AG) and anandamide (AEA), and eCB-related N-acylethanolamines [palmitoylethanolamide (PEA) and oleoylethanolamide (OEA)]. To date, there are no data on the role of these lipid mediators in FXII-HAE. Methods: Here, we analyzed plasma levels of PLC, DAGs, and eCBs in 40 patients with FXII-HAE and 40 sex- and age-matched healthy individuals. Results: Plasma PLC activity was increased in FXII-HAE patients compared to controls. Concentrations of DAG 18:1-20:4, a lipid second messenger produced by PLC, were higher in FXII-HAE compared to controls, and positively correlated with PLC activity and cleaved high molecular kininogen (cHK). Also the concentrations of the DAG metabolite, 2-AG were altered in FXII-HAE. AEA and OEA were decreased in FXII-HAE patients compared to controls; by contrast, PEA, was increased. The levels of all tested mediators did not differ between symptomatic and asymptomatic patients. Moreover, C1INH-HAE patients had elevated plasma levels of PLC, which correlated with cHK, but the levels of DAGs and eCBs were the same as controls. Conclusions: BK overproduction and BKR2 activation are linked to alteration of PLCs and their metabolites in patients with FXII-HAE. Our results may pave way to investigations on the functions of these mediators in the pathophysiology of FXII-HAE, and provide new potential biomarkers and therapeutic targets