Transient heat conduction in multi-layer walls: An efficient strategy for Laplace's method

Enhancing load calculation tools into building simulation programs requires an in-depth revision and fine tuning of the load calculation assumptions prior to the addition of the HVAC system modelling routines. It is of special interest the analysis of transient heat conduction through multi-layer walls where, in order to improve the coupling between the passive elements of the building and the HVAC systems, an improvement of the time resolution in the calculation becomes critical. Several methods have been historically used, although recently Laplace's method has been displaced by the State Space method.This paper proposes a new strategy for fine time resolution on the calculation of the response factors through Laplace's method considering a comparison with the performance of the State Space method when used to calculate conduction transfer functions. Our analysis shows that in order to achieve similar accuracy with both approaches, the State Space method requires significant additional computational time.     

Survival model in oral squamous cell carcinoma based on clinicopathological parameters,molecular markers and support vector machines

The aim of the present study is to find an intelligent and efficient model, based on Support Vector Machines (SVM), able to predict prognosis in patients with oral squamous cell carcinoma (OSCC). A total of 34 clinical and molecular variables were studied in 69 patients suffering from an OSCC. Variables were selected by means of two methods applied in parallel (Non-concave penalty and Newton’s methods). The implementation of a predictive model was performed using the SVM as a classifier algorithm. Finally, its classification ability was evaluated by discriminant analysis. Recurrence, number of recurrences, and TNM stage have been identified as the most relevant prognosis factors with both used methods. Classification rates reached 97.56% and 100% for alive and dead patients, respectively (overall classification rate of 98.55%). SVM techniques build tools able to predict with high accuracy the survival of a patient with OSCC.     

Evaluation of different solvents on flavonoids extraction efficiency from sweet oranges and ripe and immature Seville oranges

The effects of different ethanol (50%, 80% and 100%) and methanol (50%, 80% and 100%) aqueous solutions on extraction efficiency of flavonoids from sweet orange (SO) peels, ripe bitter orange (RBO) and immature bitter orange (IBO) were investigated. The highest amount of naringin was found in SO peels, compared to RBO and IBO. UHPLC-HRMS/MS results confirmed the presence of p-coumaric acid and quinic acid in all the three types of oranges while there were 90.91% and 20% possibilities for detecting caffeic acid in RBO and SO, respectively. The probabilities of detecting naringenin from IBO, RBO and SO were 100%, 63.64% and 40%, respectively. The highest neohesperidin and naringin amounts were obtained in RBO. Using 80% methanol was recommended for extracting flavonoids from SO to obtain the highest Soxhlet and precipitation yields whereas 100% ethanol was the most suitable solvent to extract flavonoids from RBO and IBO.     

Molecular fragmentation of wheat-germ agglutinin induced by food irradiation reduces its allergenicity in sensitised mice

WGA, an agglutinin from wheat germ which is largely responsible for many of wheat’s allergies, was used as a model to investigate the action of ionising radiation on WGA’s anti-nutritive effects in sensitised mice. Based on the molecular structure, the present study also examined the structural modification of WGA in relation to the range of dose. Structural integrity was monitored using HPLC, fluorescence spectrometry and circular dichroism. Results showed a loss of intrinsic activity and the formation of insoluble amorphous aggregates with a lack of native conformational structures after irradiation. Current findings suggest that the allergenic epitopes of WGA became less active and antigenic after high-dose radiation. The reduction of cytokines typical of allergic reactions, with decreased lymphocytic infiltrate, was observed in the gut of mice given irradiated versus native WGA. Food irradiation proved effective and safe in combating immunological and allergic effects of WGA.     

Sera from Patients with NMOSD Reduce the Differentiation Capacity of Precursor Cells in the Central Nervous System

Introduction: AQP4 (aquaporin-4)–immunoglobulin G (IgG)-mediated neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory demyelinating disease that affects the central nervous system, particularly the spinal cord and optic nerve; remyelination capacity in neuromyelitis optica is yet to be determined, as is the role of AQP4–IgG in cell differentiation. Material and Methods: We included three groups—a group of patients with AQP4–IgG-positive neuromyelitis optica, a healthy group, and a sham group. We analyzed differentiation capacity in cultures of neurospheres from the subventricular zone of mice by adding serum at two different times: early and advanced stages of differentiation. We also analyzed differentiation into different cell lines. Results and Conclusions: The effect of sera from patients with NMOSD on precursor cells differs according to the degree of differentiation, and probably affects oligodendrocyte progenitor cells from NG2 cells to a lesser extent than cells from the subventricular zone; however, the resulting oligodendrocytes may be compromised in terms of maturation and possibly limited in their ability to generate myelin. Furthermore, these cells decrease in number with age. It is very unlikely that the use of drugs favoring the migration and differentiation of oligodendrocyte progenitor cells in multiple sclerosis would be effective in the context of neuromyelitis optica, but cell therapy with oligodendrocyte progenitor cells seems to be a potential alternative.     

Study of a microwave digestion method for total arsenic determination in marine mussels by electrothermal atomic absorption spectrometry: application to samples from the Ria de Arousa

Arsenic determination in mussel tissue was performed by electrothermal atomic absorption spectrometry (ETAAS) with Zeeman background correction and using iridium as a chemical modifier. Samples were digested by microwave heating using a mixture of nitric and sulphuric acids. This mixture makes possible the destruction of organoarsenic compounds, specifically arsenobetaine, prior to the graphite furnace determination. Optimum pyrolysis and atomization temperatures were 1,100 and 1,800 °C, respectively. The method was precise (with RSD% < 10), accurate (study of a certified reference material: 18.4 ± 1.4 μg As g⁻¹ vs. a certified content: 18.0 ± 1.1 μg As g⁻¹; recoveries between 90 and 104%) and sensitive (LOD 0.21 μg g⁻¹ on a dry weight basis). The method was applied to the determination of arsenic in aquaculture mussels collected in four sampling campaigns from the productive Ría de Arousa (estuary sited in Galicia, NW of Spain).     

Business Cycles and Investment in Productivity-Enhancing Activities: Evidence from Spanish Firms

This paper tests the opportunity-cost theory on the long-run effects of business cycles using a panel of Spanish firms during the period 1991–2010. Under this theory, the share of productivity-enhancing activities (PEAs), such as R&D investment or on-the-job training, relative to production activities should increase during downturns because of the fall in their relative cost — in terms of forgone output. This would imply that business cycles may have a (positive) long-term impact on firms' productivity growth. In the spirit of Aghion et al. (2008), we allow the impact of the cycle on PEA to vary between firms with different access to external funding. We find that, in accordance with the opportunity-cost approach, the share of R&D investment and training expenditures on total investment outlays follow a countercyclical pattern, which in the case of R&D may be reversed by the presence of credit constraints. However, the share of investment in other non-R&D-related intangible investments is found to be acyclical, which could suggest some kind of substitution across different PEAs over the cycle.     

High-Temperature Mechanical Behavior of Extruded Mg-Y-Zn Alloy Containing LPSO Phases

The high-temperature mechanical behavior of extruded Mg_97?3x Y_2x Zn _x (at. pct) alloys is evaluated from 473 K to 673 K (200 °C to 400 °C). The microstructure of the extruded alloys is characterized by Long Period Stacking Ordered structure (LPSO) elongated particles within the magnesium matrix. At low temperature and high strain rates, their creep behavior shows a high stress exponent (n = 11) and high activation energy. Alloys behave as a metal matrix composite where the magnesium matrix transfers part of its load to the LPSO phase. At high-temperature and/or low stresses, creep is controlled by nonbasal dislocation slip. At intermediate and high strain rates at 673 K (400 °C) and at intermediate strain rates between 623 K and 673 K (350 °C and 400 °C), the extruded alloys show superplastic deformation with elongations to failure higher than 200 pct. Cracking of coarse LPSO second-phase particles and their subsequent distribution in the magnesium matrix take place during superplastic deformation, preventing magnesium grain growth.