Perceived and actual change in job satisfaction.

Analysis of identified questionnaire data collected from 196 office employees at the start and end of a 6-mo period showed that change in overall job satisfaction as perceived at the end was a very poor, though statistically significant, proxy measure of change as computed from initial and terminal reports on levels of satisfaction. Perceived change in job satisfaction had zero regression on initial satisfaction but regressed very significantly on terminal satisfaction and on change in 14 job aspects as perceived at the end of the period. The findings cast serious doubts on the usefulness of the quasilongitudinal design in studies of the impact of technological and organizational changes upon job satisfaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reduction of verotoxigenic Escherichia coli in production of fermented sausages

After a number of foodborne outbreaks of verotoxigenic Escherichia coli involving fermented sausages, some countries have imposed regulations on sausage production. For example, the US Food Safety and Inspection Service requires a 5 log(10) reduction of E. coli in fermented products. Such regulations have led to a number of studies on the inactivation of E. coli in fermented sausages by changing processing and post-processing conditions. Several factors influence the survival of E. coli such as pre-treatment of the meat, amount of NaCl, nitrite and lactic acid, water activity, pH, choice of starter cultures and addition of antimicrobial compounds. Also process variables like fermentation temperature and storage time play important roles. Though a large variety of different production processes of sausages exist, generally the reduction of E. coli caused by production is in the range 1-2 log(10). In many cases this may not be enough to ensure microbial food safety. By optimising ingredients and process parameters it is possible to increase E. coli reduction to some extent, but in some cases still other post process treatments may be required. Such treatments may be storage at ambient temperatures, specific heat treatments, high pressure processing or irradiation. HACCP analyses have identified the quality of the raw materials, low temperature in the batter when preparing the sausages and a rapid pH drop during fermentation as critical control points in sausage production. This review summarises the literature on the reduction verotoxigenic E. coli in production of fermented sausages.     

Enterotoxin formation by Clostridium perfringens during sporulation and vegetative growth

Growth, sporulation and enterotoxin production have been followed for three different strains of Clostridium perfringens on a vegetative (FTG) medium and a sporulation (DS) medium. Enterotoxin production was followed by use of enzyme-linked immunosorbent assay (ELISA). All strains produced enterotoxin under both vegetative growth and sporulation in spite of the fact that one strain is known to be enterotoxin negative. The presumed negative strain produced about the same amount of enterotoxin on both media (1 ng/ml). The two other strains produced about 1000–2000 times more enterotoxin during sporulation than during vegetative growth.     

Thermodynamic Calculations on the Chemical Vapor Deposition of Silicon Nitride and Silicon from Silane and Chlorinated Silanes

After a discussion of the thermochemical values of the Si–H–Cl–N system which occur in the literature, CVD phase diagrams are presented which include contours of constant deposition efficiency. The temperature range considered is from 800 to 2600 K. A number of chlorinated silanes as well as silane can be used as a silicon source, while ammonia is used as the nitrogen source. The effects of pressure variation and dilution by nitrogen and hydrogen are also included. Some initial calculations concerning silicon diimide are made. The CVD phase diagrams are used to describe several mechanisms occurring during the formation of silicon nitride from the gas phase.     

Proximity,accessibility and choice: A matter of taste or condition?*

Drawing on a combination of register data and travel survey data, this research explores changes in the accessibility to different amenities for the Swedish population between 1995 and 2005, as well as the reasons behind the changes: redistribution of either amenities or the population. Overall, proximity has increased concerning most of the amenities during the period. However, despite decreasing ‘potential’ distances, actual travel distances are growing longer due to, for example, an increasing selectivity in preferences. An analysis of the accessibility development for service amenities shows that restructuring within the service sector is the main cause of the changes, and to a lesser extent population redistribution. Resumen. Haciendo uso de una combinación de datos de registros y encuestas de viajes, este estudio explora cambios en la accesibilidad de diferentes servicios y lugares de recreo para la población sueca entre 1995 y 2005, así como las razones detrás de dichos cambios: una redistribución de los servicios o de la población. En conjunto, la proximidad ha aumentado con respecto a la mayoría de los servicios durante el periodo estudiado. Sin embargo, a pesar de las reducciones en distancias “potenciales”, las distancias de viaje están aumentando debido a por ejemplo una mayor selectividad en las preferencias. Un análisis del desarrollo de la accesibilidad de servicios y ocio muestra que la reestructuración dentro del sector servicios es la causa principal de los cambios y, en menor medida, la redistribución de la población.      

High-accuracy turning with slender boring bars

The paper presents the theoretical background for new approaches for achieving high accuracy in finish turning with slender tools.The approaches are developed especially for high-accuracy turning with vibrationsdamped boring bars with a length-to-diameter ratio up to14.The approaches are based on established force models of turning operations and utilize a three-pass scheme where the deflection of the boring bar is calculated and compensated for in the final passes.Very good results are achieved in practical machining tests for a great variation of cutting conditions.Experiments show that the typical diameter error is 0.01 mm,even in situation where the tool deflection is 0.3 mm.