The effect of positive feedback on industrial housekeeping and accidents; A long-term study at a shipyard

The experiments aimed to determine the effects of performance feedback on housekeeping behavior and consequently, on injuries over a longer period of time, and also to assess the validity of well-known Heinrich's axioms with respect to accident causation. The study was conducted at two production halls of a shipyard. Nine performance targets were set for housekeeping performance. An observation method was developed to measure performance. After we determined the baseline, feedback on performance was given by posting the results of each observation round as a large graph on the wall. The housekeeping index was significantly improved in both halls after the feedback was started. The effect persisted throughout the two-year follow-up period. Accidents were reduced by 70–90%, much more than expected merely on the basis of improved housekeeping. The effect of feedback on accidents persisted for the three-year follow-up period. The possible mechanisms are discussed.     

Assessment of Social Services’ Disaster Risk Management: Case Finland

Local actors are crucial in disaster risk management; thus, their capacities should be assessed periodically. In this study, local social services’ preparedness plans were assessed using Emergency Management Program Measurement and quantitative document analysis. The specific aim was to study how social service areas of various sizes were prepared for disasters in Finland. The results showed that disaster risk management capacity varied significantly between large and small service areas. Larger areas were better prepared for supporting management, and had better procedures to activate their response, modern public information and deeper cooperation with the private sector and the civil society. The differences might derive from the fact that large areas have more resources allocated to disaster risk management.     

Ultrastructure of the frog retina after high-pressure freezing and freeze substitution

In many types of tissue, high-pressure freezing (HPF), followed by freeze substitution, can produce excellent ultrastructural preservation at depths over 10 times that obtained by other cryofixation techniques. However, in the case of neural tissue, the benefits of HPF have not been realized. In the present study, isolated frog ( Rana pipiens) retina was sliced at a thickness of 150 or 350 μm, rapidly frozen in a Balzers HPM 010 high-pressure freezer, and freeze substituted with 1% OsO₄ and 0.1% tannic acid in acetone. Specially designed HPF chambers and specific freezing media (35% high-MW dextran for 150-μm slices or 15% low-MW dextran for 350-μm slices) were required for adequate freezing.
The quality of preservation after HPF was excellent throughout the retina in both the 150- and 350-μm slices, compared with chemically fixed slices. Specifically, HPF resulted in better preserved cellular, mitochondrial and nuclear membranes in all retinal layers.
This is the first study to successfully cryofix all of the layers of the retina. The increased depths of adequate freezing achieved by HPF should facilitate various ultrastructural studies of retina, as well as of other CNS tissues, where preservation approaching that of the 'native' state is required.     

Heat and Mass Transfer Analogy Studies of Binary Liquid Mixture in Comparison with Eteanol-n-Heptane Evaporating to Air

ABSTRACT

An expenmental and theoretical study of heat and mass transfer analogy and a comparison of that to a binary liquid mixture evaporation is presented. Common organic solvents, ethanol and n-heptane, were used to form an alcohol - hydrocarbon mixture. Studies were carried out in a horizontal rectangular channel having air flow velocities of 0.2 – 0.9 m/s. Heat transfer coefficients were measured with a copper plate resistor and mass transfer coefficients with a square pool. The heat and mass transfer analogy is presented for a system having two evaporating compounds with a fixed value of air flow and verified by measuring and comparing mass transfer coefficients for distilled water with air flow velocities of 0.2 - 0.9 mls. An illustrative example of the use of the theory for industrial ventilation is presented.     

Evaluation of a participatory ergonomic intervention process in kitchen work

We evaluated a participatory ergonomic intervention process applied in 59 municipal kitchens. In groups of three to five kitchens, the workers participated in eight workshops, and generated and evaluated solutions to optimize musculoskeletal load in their work. An ergonomist initiated and supported the process. By the end, 402 changes were implemented. Evaluative data were collected using research diaries, questionnaires, and focus group interviews. The intervention model proved feasible and the participatory approach was mostly experienced as motivating. The workers’ knowledge and awareness of ergonomics increased, which improved their ability to tackle ergonomic problems by themselves. The changes in ergonomics were perceived to decrease physical load and improve musculoskeletal health. As hindering factors for implementation, lack of time and motivation, and insufficient financial resources were mentioned. In addition, the workers expressed a wish for more support from the management, technical staff, and ergonomists.     

Improvements and Modifications to Room‐Temperature Fabrication Method for Dielectric Li2MoO4 Ceramics

Dielectric properties of lithium molybdate disks fabricated by moistening water‐soluble Li₂MoO₄ powder, compressing it, and postprocessing the samples at 120°C, were improved by the optimization of powder particle size, sample pressing pressure, and postprocessing time. It appeared that the postprocessing temperature of the Li₂MoO₄ ceramics could be chosen so as to be applicable to the associated integrated materials as long as the postprocessing time was adequately adjusted to ensure the removal of the residual water. In addition, the dielectric properties of Li₂MoO₄ ceramic were modified with an inclusion of suitable additives. For example, at 1 GHz the relative permittivity of Li₂MoO₄ disks fabricated at room temperature and postprocessed at 120°C was increased from 6.4 to 8.8 with an addition of 10 vol% of rutile TiO₂ and to 9.7 with an addition of 10 vol% of BaTiO₃. At the same time the loss tangent value increased from 0.0006 to 0.0014 and to 0.011, respectively.     

Methods for detection of irradiation of spices

European Food Research and Technology - Three types of methods for the identification of irradiation of spices were tested as potential control methods. The methods were microbiological, combining...     

Probiotic and milk technological properties of Lactobacillus brevis

Two Lactobacillus brevis strains ATCC 8287 and ATCC 14869(T), were evaluated for their applicability as putative probiotics in dairy products. The strains expressed good in vitro adherence to human Caco-2 and Intestine 407 cells and tolerated well low pH, bile acids and pancreatic fluid under in vitro conditions. In antimicrobial activity assays, strain ATCC 8287 showed inhibitory properties toward selected potential harmful microorganisms, particularly against Bacillus cereus. Both L. brevis strains were resistant to vancomycin, which is typical for the genus Lactobacillus. The L. brevis strains were not able to acidify milk to yoghurt but were suitable as supplement strains in yoghurts. This was shown by producing a set of yoghurt products and analysing their rheological and sensory properties during a cold storage period of 28 days. Survival of the strains through human intestine was examined in 1-week feeding trials. Despite its human origin, L. brevis ATCC 14869(T) could not survive through the gastrointestinal (GI) tract, whereas L. brevis ATCC 8287 was detected in the faecal samples taken during and immediately after ingestion of the strain. In conclusion, L. brevis ATCC 8287 is a promising candidate as a probiotic supplement in dairy products.     

Vacancy formation and solid solubility in the U-Zr-N system

For the purpose of developing a nuclear fuel with enhanced thermophysical properties and better irradiation performance density functional theory calculations are used to explore UN, ZrN and (U, Zr)N. Negative deviation of ground state energy from the ideal solution model as well as energetically favourable maximal distance between substitutional metal atoms in respective nitrides indicate mutual solubility of UN and ZrN at all temperatures. Nitrogen vacancy formation energies in UN (1.81 eV) and ZrN (1.40 eV) are considerably lower than metal vacancy formation energies. A substitutional Zr atom in UN has little effect on nitrogen vacancy formation energies (∼1.79 eV), while U in ZrN decreases the value by ∼0.1 eV (∼1.30 eV) due to elastic stress and charge density redistribution in the material. The relative distance between a substitutional metal atom and a vacancy in UN has little influence over the radially declining displacement pattern induced by the substitutional atom, while in ZrN the relaxation of atoms is governed by the position of the vacancy. The calculated vacancy formation energies indicate a lower surface energy of ZrN in comparison with UN.     

Occurrence of nitrifiers and diversity of ammonia-oxidizing bacteria in developing drinking water biofilms

We studied the population dynamics of nitrifying bacteria during the development of biofilms up to 233 or 280 days on polyvinylchloride pipes connected to two full-scale drinking water distribution networks supplying processed and chloraminated surface water. The numbers of nitrifiers in biofilms were enumerated at intervals of 10–64 days by the most probable number (MPN) method at waterworks and at several study sites in distribution network areas. The numbers of nitrifiers increased towards the distal sites. The highest detected MPN counts of ammonia-oxidizing bacteria (AOB) for study areas 1 and 7 were 500 MPN cm⁻² and 1.0×10⁶ MPN cm⁻², and those of nitrite-oxidizing bacteria (NOB) 96 MPN cm⁻² and 2.2×10³ MPN cm⁻², respectively. The diversity of AOB was determined by PCR amplifying, cloning and sequencing the partial ammonia monooxygenase (amoA) gene of selected biofilm samples presenting different biofilm ages. The PCR primers used, A189 and A682, also amplified a fragment of particulate methane monooxygenase (pmoA) gene of methane-oxidizing bacteria. The majority of biofilm clones (24 out of 30 studied) contained Nitrosomonas amoA-like sequences. There were only two pmoA-like sequences of Type I methanotrophs, and four sequences positioned in amoA/pmoA sequence groups of uncultured bacteria. From both study area very similar or even completely identical Nitrosomonas amoA-like sequences were obtained despite of high difference in AOB numbers. The results show that the conditions in newly formed biofilms in drinking water distribution systems favor the growth of Nitrosomonas-type AOB.