Solvent-Assisted Crystallization of Fatty Acid Alkyl Esters from Animal Fat

An easy and efficient method for the separation of saturated and unsaturated fatty acid mono alkyl esters, prepared from animal fat, was developed. The most efficient separation was achieved by the use of solvents such as methanol and acetone at low temperatures. The dilution of the alkyl esters with 10 times the amount of solvent (10:1 v/w) and storage of the mixture for 4 h at ?22 °C could be defined as optimum conditions. After filtration of the saturated fraction at the corresponding temperature very pure fractions were obtained. For fatty acid methyl esters deriving from tallow, with an initial content of saturated fatty acids of almost 50 %, a saturated ester fraction with only 5 % unsaturated fatty acids and an unsaturated ester fraction with about 9 % of saturated fatty acids could be obtained. The solvent easily could be recovered by distillation. In addition fatty acid ethyl, 1‐propyl, 2‐propyl, 1‐butyl, tert‐butyl and 3‐methyl‐1‐butyl esters were prepared and separated into saturated and unsaturated fractions. All fractions were analyzed according to the fatty acid compositions and showed similar or slightly worse results compared to the methyl esters. The cold filter plugging points of the unsaturated fractions were measured, showing the lowest value for the unsaturated methyl ester fraction at ?26 °C. The fractionation with the use of solvents is an easy tool in order to obtain fatty acid alkyl esters with excellent cold temperature behavior out of animal fat.     

A New Prototype Two‐Phase (TiNi)–(β‐W) SMA System with Tailorable Thermal Hysteresis

The Ti–Ni–W two‐phase shape memory alloy (SMA) thin film system is presented as a prototype for new SMAs with tailorable thermal transformation hysteresis (ΔT). The concept is to combine the SMA TiNi with almost insoluble W to create the two‐phase system (TiNi)–(β‐W). This system behaves like a pseudobinary TiNi system. Phase transformation behavior for compositions above the solubility limit of W in TiNi exhibit a B2–R phase transformation with characteristically small ΔT. Moreover, ΔT is dependent on the amount of W and it can be tailored to zero and even negative. This phenomenon is rationalized as being due to the mechanical interaction between the phases B2‐TiNi and β‐W. The presented results are very promising for the development of high‐speed Ti–Ni‐based SMA actuators.     

Growth modulation of low density lipoprotein receptor sterol sensitivity in cultured human fibroblasts

Sterols regulate low density lipoprotein (LDL) receptor and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase gene expressions by end product repression. Studies on cultured cells have shown that growing cells have a higher LDL uptake than quiescent cells and that incubation of cells with growth factors or mitogenic compounds leads to sterol-resistant upregulation of LDL receptor gene expression. The recent finding that elevated LDL receptor activity in acute myelogenous leukemia cells was characterized by a decreased sensitivity to downregulation by sterols raises the possibility that the mechanism behind this is related to the cellular growth rate. By using cultured human fibroblasts as a model system we therefore studied whether growth modulation of sterol sensitivity takes place in normal actively growing cells. Judging from the ability of sterols (25-hydroxycholesterol+cholesterol) to inhibit ¹²⁵I-LDL degradation, we found that the sensitivity to sterols varied markedly between cells of different densities. The lowest sensitivity to sterols and highest ¹²⁵I-LDL degradation rate were found in subconfluent cells, whereas sparse and confluent cells were the most sensitive ones. In contrast to the LDL receptor, HMG-CoA reductase sterol sensitivity did not appear to be growth regulated. We conclude that growth-dependent modulation of sterol sensitivity and LDL receptor activity takes place in normal human fibroblasts. Modulation of sterol sensitivity may be an important mechanism to ensure an adequate cholesterol supply in growing cells.     

Effects of psychological hardiness, job demands, and job control on sickness absence: A prospective study.

This study prospectively investigated the effects of psychological hardiness, job control, and job demands on medically certified sickness absence. Data from a questionnaire survey were combined with archival data for sickness absence among 7,239 civilian and military employees of the Norwegian Armed Forces (84.3% male, 69.8% military). A 2-component hurdle regression was used in the statistical analyses of the sickness absence data. After controlling for age, sex, and baseline absence, hardiness predicted both the likelihood of having any sickness absence (odds ratio = 0.97) and the number of absence spells (a 6.5% decrease in the expected count for 1 standard deviation change in hardiness). In addition, an interaction was found among hardiness, job control, and psychological demands. When demands were high, high job control was associated with more absence among employees with low levels of hardiness. Together, these findings point to hardiness as an important individual resource in relation to health, and that it is necessary to consider individual differences when examining the effects of work characteristics. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Future manufacturing approaches in the chemical and pharmaceutical industry

In order to develop future manufacturing strategies the chemical and pharmaceutical industry works on the implementation of process intensification and new modularization methods. In this paper current challenges, process intensification approaches and future manufacturing initiatives are summarized and discussed.     

Practice world

Civil Engineer Sigurd Hveem at the Norwegian Building Research Institute, BI, describes the laboratory and field tests carried out on the dynamic response of different lightweight timber floors to establish new design guidelines. NBI are also looking at theoretical calculation methods in order to predict the results obtained by measuring dynamic properties.