Search results for "pane"
showing 10 items of 1074 documents
Overexpression of interleukin-23, but not interleukin-17, as an immunologic signature of subclinical intestinal inflammation in ankylosing spondylitis
2009
Objective Subclinical gut inflammation is common in spondylarthritis, but the immunologic abnormalities underlying this process are undefined. Perturbation of the interleukin-23 (IL-23)/Th17 axis has emerged as a fundamental trigger of chronic inflammation. This study was undertaken to investigate the expression and tissue distribution of IL-23/Th17–related molecules in Crohn's disease (CD) and in subclinical gut inflammation in ankylosing spondylitis (AS). Methods Quantitative gene expression analysis of Th1/Th2 and IL-23/Th17 responses was performed in intestinal biopsy samples obtained from 12 patients with CD, 15 patients with AS, and 13 controls. IL-23 tissue distribution and identific…
The dynamics of radical right-wing populist party preferences and perceived group threat: A comparative panel analysis of three competing hypotheses …
2014
Existing cross-sectional research considers citizens' preferences for radical right-wing populist (RRP) parties to be centrally driven by their perception that immigrants threaten the well-being of the national ingroup. However, longitudinal evidence for this relationship is largely missing. To remedy this gap in the literature, we developed three competing hypotheses to investigate: (a) whether perceived group threat is temporally prior to RRP party preferences, (b) whether RRP party preferences are temporally prior to perceived group threat, or (c) whether the relation between perceived group threat and RRP party preferences is bidirectional. Based on multiwave panel data from the Netherl…
Self-reported health versus biomarkers: does unemployment lead to worse health?
2020
Abstract Objectives This paper examines the relationship between unemployment and health using both subjective and biometric information on health status. Study design Longitudinal panel data. Methods We compare the results of regressions of unemployment on self-reported health with those of regressions of unemployment on health as measured with biomarkers (hypertension and levels of blood glucose and C-reactive protein). Using the panel structure of our data, we account for selection bias with respect to unemployment by controlling for health before exposure to unemployment. Results We observe a striking pattern. Using self-reported health as the outcome variable, we find a link between un…
In Vitro Percutaneous Penetration of Acyclovir from Solvent Systems and Carbopol 971-P Hydrogels: Influence of Propylene Glycol
2005
The mechanism underlying propylene glycol (PG) effects on acyclovir (ACV) penetration through human epidermis were studied. Solvent systems and Carbopol gels containing increasing percentage of PG (from 0% to 70%, w/w) were used. Viscosity studies of both vehicles were carried out to characterise the influence of rheological behaviour. In solvent systems skin permeation values of ACV increase as the concentration of PG increase yielding a maximum enhancement ratio (ER = 10) for 70% PG. The release rate of ACV from gels was determined. Higuchi's model was used to estimate the apparent diffusion coefficient of the drug. These values show a decrease as the content of PG in the vehicle increase…
Unveiling the Antecedents of International Diversification: An Agency Theory Approach
2014
While various studies have developed hypotheses about the antecedents of international diversification drawing mainly on the resource-based view, the behavioral theory of the firm, and the transaction costs literature, we advance our understanding by investigating the explanatory power of agency costs of free cash flow arguments. Using a sample panel of 167 Italian firms longitudinally evaluated during the 1980-2010 period, this study tests whether the firm’s choice to spread operations in multiple foreign countries is conditioned by excess of free cash flow and debt, especially in firm-contexts where agency problems are exacerbated by managers or large shareholders’ opportunism. We find th…
Unveiling the Antecedents of International Diversification: An Agency Theory Approach
2014
While various studies have developed hypotheses about the antecedents of international diversification drawing mainly on the resource-based view, the behavioral theory of the firm, and the transaction costs literature, we advance our understanding by investigating the explanatory power of agency costs of free cash flow arguments. Using a sample panel of 167 Italian firms longitudinally evaluated during the 1980-2010 period, this study tests whether the firm’s choice to spread operations in multiple foreign countries is conditioned by excess of free cash flow and debt, especially in firm-contexts where agency problems are exacerbated by managers or large shareholders’ opportunism. We find th…
An agent-based model to support the preliminary design and operation of heating and power grids with cogeneration units and photovoltaic panels in de…
2022
The increase in the energy demands of residential neighborhoods constitutes a huge challenge to be faced. A viable option lies in the insertion of both renewable energy production systems and cogeneration units within urban territories. On-site production allows for the satisfaction of the heating and electrical demands of end-users and favors the distribution of produced energy within the neighborhood, especially under the regulatory framework of energy communities. This paper proposes a tool to model heating and electricity networks integrated with cogeneration units and PV panels installed in urban areas. The tool accounts for the following possibilities: (i) energy flow management and p…
Cracking of n-heptane on a hzsm-5 zeolite. The influence of acidity and pore structure
1985
Abstract The crackino of n-heptane on a HZSM-5 zeolite has been studied in a continuous qlass flow reactor, at atmospheric pressure, up to 470°C. The initial selectivities to the different reaction products, kinetic rate constants, activation energies and decay parameters have been calculated and compared with those obtained using a large pore zeolite (HYUS). A different product distribution is obtained with the two zeolites. In that way, and considering initial selectivities, different C 6 /C 1 , C 5 /C 2 , C 4 /C3, i-C 4 /n-C 4 , ethylene/ethane, propylene/propane ratios have been found on the two zeolite catalysts. The results have been quantitatively explained by considerinq a direct cr…
Diastereoselective synthesis of antiquorin and related polyoxygenated atisene-type diterpenes
2007
Abstract A diastereoselective approach to polyoxygenated atisene-type diterpenes starting from (S)-(+)-carvone is described. The key steps used in the preparation of the atisene framework are an intramolecular Diels–Alder reaction, an intramolecular diazoketone cyclopropanation, an endocyclic cyclopropane ring cleavage and the regioselective reduction of an allylic bromide by a low-valent chromium species. The synthesis of natural atisanes antiquorin (1), atis-16-ene-3,14-dione (3), atis-16-ene-2,3,14-trione (8) and 3β-hydroxy-atis-16-ene-2,14-dione (9) following this approach is presented. Also described is the synthesis of 18-hydroxy-atis-16-ene-3,14-dione (5), the structure erroneously a…
A procedure to evaluate the seven parameters of the two-diode model for photovoltaic modules
2019
Abstract The paper presents an analytical procedure to calculate the seven parameters of the two-diode model of photovoltaic (PV) panels for any value of the solar irradiance and cell temperature. Six parameters (the photocurrent, the diode reverse saturation currents, the quality factor of the first diode and the series and shunt resistances), are evaluated by solving the equations related to the properties of the main points of the current-voltage (I-V) characteristics. The further information, necessary to calculate the entire set of seven truly independent parameters, is based on two conditions that have to be simultaneously satisfied: 1) the exclusion of negative values of the model pa…