Modeling the methyldiethanolamine-piperazine scrubbing system for CO<Subscript>2</Subscript> removal: Thermodynamic analysis

Aqueous solutions of methyldiethanolamine (MDEA) and piperazine (PZ) are commonly used solvent nowadays. In this work a thermodynamic analysis with the Electrolyte-NRTL model has been performed for systems composed of acidic gases and MDEA + PZ aqueous solution. ASPEN Plus® has been used for thermodynamic modeling. Values of binary interaction parameters for liquid phase activity coefficients have been estimated from regressions of experimental data. Moreover, the influence of the interactions between ion pairs and MDEA or PZ molecular species has been analyzed. The final aim is to obtain a reliable tool for design and simulation of absorption and stripping columns, fundamentals also in order to carry out energy saving studies.

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Electroporation-Induced Cell Modifications Detected with THz Time-Domain Spectroscopy

Electroporation (electropermeabilization) increases the electrical conductivity of biological cell membranes and lowers transport barriers for normally impermeant materials. Molecular simulations suggest that electroporation begins with the reorganization of water and lipid head group dipoles in the phospholipid bilayer interface, driven by an externally applied electric field, and the evolution of the resulting defects into water-filled, lipid pores. The interior of the electroporated membrane thus contains water, which should provide a signature for detection of the electropermeabilized state. In this feasibility study, we use THz time-domain spectroscopy, a powerful tool for investigating biomolecular systems and their interactions with water, to detect electroporation in human cells subjected to permeabilizing pulsed electric fields (PEFs). The time-domain response of electroporated human monocytes was acquired with a commercial THz, time-domain spectrometer. For each sample, frequency spectra were calculated, and the absorption coefficient and refractive index were extracted in the frequency range between 0.2 and 1.5 THz. This analysis reveals a higher absorption of THz radiation by PEF-exposed cells, with respect to sham-exposed ones, consistent with the intrusion of water into the cell through the permeabilized membrane that is presumed to be associated with electroporation.     

Nonalcoholic Fatty Liver: A Possible New Target for Type 2 Diabetes Prevention and Treatment

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder worldwide. Several lines of evidence have indicated a pathogenic role of insulin resistance, and a strong association with type 2 diabetes (T2MD) and metabolic syndrome. Importantly, NAFLD appears to enhance the risk for T2MD, as well as worsen glycemic control and cardiovascular disease in diabetic patients. In turn, T2MD may promote NAFLD progression. The opportunity to take into account NAFLD in T2MD prevention and care has stimulated several clinical studies in which antidiabetic drugs, such as metformin, thiazolidinediones, GLP-1 analogues and DPP-4 inhibitors have been evaluated in NAFLD patients. In this review, we provide an overview of preclinical and clinical evidences on the possible efficacy of antidiabetic drugs in NAFLD treatment. Overall, available data suggest that metformin has beneficial effects on body weight reduction and metabolic parameters, with uncertain effects on liver histology, while pioglitazone may improve liver histology. Few data, mostly preclinical, are available on DPP4 inhibitors and GLP-1 analogues. The heterogeneity of these studies and the small number of patients do not allow for firm conclusions about treatment guidelines, and further randomized, controlled studies are needed.     

A 3D moisture-stress FEM analysis for time dependent problems in timber structures

This paper presents a 3D moisture-stress numerical analysis for timber structures under variable humidity and load conditions. An orthotropic viscoelastic-mechanosorptive material model is specialized on the basis of previous models. Both the constitutive model and the equations needed to describe the moisture flow across the structure are implemented into user subroutines of the Abaqus finite element code and a coupled moisture-stress analysis is performed for several types of mechanical loads and moisture changes. The presented computational approach is validated by analyzing some wood tests described in the literature and comparing the computational results with the reported experimental data.     

Design and analysis of an integrated antiresonant reflecting optical waveguide refractive-index sensor

An integrated optical waveguide refractometer, believed to be novel, is presented. The sensor is based on an antiresonant reflecting optical waveguide and uses the strong attenuation dependence on the refractive index of antiresonant cladding layers as the sensing principle. The theory and the operation of the sensor are discussed in terms of one- and two-dimensional geometry. The theoretical predictions and numerical analysis show that a versatile sensor can be realized. The design trade-offs are discussed, and the sensitivity and measurement range are presented.     

"Their ideas of beauty are, on the whole, the same as ours": Consistency and variability in the cross-cultural perception of female physical attractiveness.

The consistency of physical attractiveness ratings across cultural groups was examined. In Study 1, recently arrived native Asian and Hispanic students and White Americans rated the attractiveness of Asian, Hispanic, Black, and White photographed women. The mean correlation between groups in attractiveness ratings was r?=?.93. Asians, Hispanics, and Whites were equally influenced by many facial features, but Asians were less influenced by some sexual maturity and expressive features. In Study 2, Taiwanese attractiveness ratings correlated with prior Asian, Hispanic, and American ratings, mean r?=?.91. Supporting Study 1, the Taiwanese also were less positively influenced by certain sexual maturity and expressive features. Exposure to Western media did not influence attractiveness ratings in either study. In Study 3, Black and White American men rated the attractiveness of Black female facial photos and body types. Mean facial attractiveness ratings were highly correlated (r?=?.94), but as predicted Blacks and Whites varied in judging bodies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of adverse weather conditions in acute releases of hazardous substances, Texas, 2000-2001

High winds, flooding, lightning, and other phenomena associated with adverse weather can cause power failures, equipment damage, and process upsets resulting in chemical releases. Of the 5000 events in Texas that were reported to the Hazardous Substances Emergency Events Surveillance (HSEES) system during 2000-2001, adverse weather conditions contributed to 110 (2%) events. Rain was the most frequent adverse weather condition. Most events to which adverse weather conditions contributed occurred during June or September; these months correspond with the high temperature and hurricane season in Texas. Most events occurred in coastal counties with large numbers of industrial facilities. Three industries reported the majority of events: industrial and miscellaneous chemicals manufacturing; petroleum refining; and plastics, synthetics, and resin manufacturing. Power failures were associated more often with adverse weather-related events than with nonweather-related events. Releases occurred most commonly from ancillary process equipment and process vessels. Events associated with adverse weather-related conditions involved nine victims. System and process design improvements, such as improved backup power generation and redesigned secondary containment systems, could be explored to reduce the potential negative effects of severe weather.     

Hourly indoor radon measurements in a research house

This paper reports and discusses the behaviour of radon concentration with time in an uninhabited dwelling. The relationship between variations in radon concentrations and indoor-outdoor temperatures and wind intensity has also been discussed. Radon concentration was measured hourly in a house located at a height of 800 m in the Lombard Prealps, at the top of the Valassina valley. The wind velocity and indoor-outdoor temperatures were measured by means of a meteorological station located on the terrace of the house. The data were analysed using the LBL model for indoor-outdoor air exchange and the models for the indoor accumulation of radon due to exhalation from building materials and pressure-driven infiltrations located underground. The role of wind and indoor-outdoor temperatures were analysed. The agreement of measurements with modelling clearly demonstrates the importance of the different sources of indoor radon. As the investigation was conducted in an uninhabited house, the measurements were not affected by the behaviour of people, e.g. opening and closing of windows. Measurements of the outdoor atmospheric concentrations of (222)Rn provide an index of the atmospheric stability, the formation of thermal inversions and convective turbulence.     

Use of correspondence discriminant analysis to predict the subcellular location of bacterial proteins

Correspondence discriminant analysis (CDA) is a multivariate statistical method derived from discriminant analysis which can be used on contingency tables. We have used CDA to separate Gram negative bacteria proteins according to their subcellular location. The high resolution of the discrimination obtained makes this method a good tool to predict subcellular location when this information is not known. The main advantage of this technique is its simplicity. Indeed, by computing two linear formulae on amino acid composition, it is possible to classify a protein into one of the three classes of subcellular location we have defined. The CDA itself can be computed with the ADE-4 software package that can be downloaded, as well as the data set used in this study, from the P?le Bio-Informatique Lyonnais (PBIL) server at http://pbil.univ-lyon1.fr.     

Reduction of immunoreactivity of bovine beta-lactoglobulin upon combined physical and proteolytic treatment

Bovine beta-lactoglobulin was hydrolyzed with trypsin or chymotrypsin before, during and after treatment at 600 MPa and pH 6.8 for 10 min at 30, 37 and 44 degrees C. The extent of beta-lactoglobulin hydrolysis under pressure was noticeably higher than at atmospheric pressure, particularly when chymotrypsin was used. Addition of proteases at ambient pressure to previously pressure-treated beta-lactoglobulin gave only a modest increase in proteolysis with respect to the untreated protein. Products of enzyme hydrolysis under pressure were separated by reverse-phase HPLC, and were found to be different from those obtained at atmospheric pressure when chymotrypsin was used. The residual immunochemical reactivity of the products of combined pressure-enzyme treatment was assessed on the unresolved hydrolysates by ELISA tests using polyclonal and monoclonal antibodies, and on individual hydrolytic fractions by Western Blotting using sera of paediatric patients allergic to whey proteins in cow milk. The immunoreactivity of the whole hydrolysates was related to their content of residual intact beta-lactoglobulin, and no immunochemical reactivity was found for all the products of chymotrypsin hydrolysis under pressure. The results indicate that chymotrypsin effectively hydrolysed hydrophobic regions of beta-lactoglobulin that were transiently exposed during the pressure treatments and that were not accessible in the native protein or in the protein that had been previously pressure treated.