High-temperature liquid chromatography coupled on-line to a continuous-flow biochemical screening assay with electrospray ionization mass spectrometric detection

The potential of high-temperature liquid chromatography (HTLC) was investigated in an on-line combination with a screening system for bioactive compounds against the enzyme cathepsin B. Samples were separated by HTLC and subsequently analyzed by an on-line continuous-flow enzymatic assay. Detection was performed by electrospray ionization mass spectrometry, revealing both the bioactivity and the molecular mass of the bioactive compounds. Compared to conventional reversed-phase liquid chromatography, the amount of methanol necessary for separation could be decreased to only 10%, which improved the compatibility of LC with a biochemical assay. Sufficient preheating of the mobile phase prior to the separation and postcolumn cooling to prevent deactivation of the enzyme, even at column temperatures as high as 208 degrees C, was achieved as indicated by the reliable peak shapes obtained. The sensitivity was comparable with previously described systems operating at ambient temperatures as similar IC50 values were obtained. Exposing the inhibitors to high temperatures did not lead to thermal decomposition. The separation of inhibitors and the subsequent biochemical assay was performed either isothermally at various temperatures or by applying various temperature gradients as well as at various flow rates. The results obtained clearly show the compatibility of HTLC with an enzymatic screening assay.     

Study of a new energy efficient process for French fries production

A new, energy efficient production process for French fries was developed and evaluated. Superheated steam (SHS) was used for evaporation of water instead of pre-drying with air and par-frying with oil. The product was frozen by vacuum cooling. Unfortunately, with this process it was not possible to reach the quality of conventional French fries. Sensory analysis indicated that the main quality defect was a tough crust with a fatty appearance. Confocal Scanning Laser Microscopy showed that this was caused by skin formation on the surface during both SHS drying and vacuum cooling. A frying step was necessary to obtain a porous crust. A satisfactory product quality was feasible after drying with SHS instead of air. Due to the concessions made for the product quality, the final energy reduction was limited. Nevertheless, this study has gained more insight into how processing affects potato tissue on micro-scale and it has shown that a porous structure is essential for good quality French fries.     

A system to test the ground surface conditions of construction sites--for safe and efficient work without physical strain

Ground surface conditions on construction sites have an important influence on the health and safety of workers and their productivity. The development of an expert-based "working conditions evaluation" system is described, intended to assist site managers in recognising unsatisfactory ground conditions and remedying these. The system was evaluated in the period 2002-2003. The evaluation shows that companies recognize poor soil/ground conditions as problematic, but are not aware of the specific physical workload hazards. The developed methods allow assessment of the ground surface quality and selection of appropriate measures for improvement. However, barriers exist at present to wide implementation of the system across the industry. Most significant of these is that responsibility for a site's condition is not clearly located within contracting arrangements, nor is it a topic of serious negotiation.     

Behavioural change phases of different stakeholders involved in the implementation process of ergonomics measures in bricklaying

The objective of this qualitative study was to assess whether a hypothesised sequential order of behavioural change phases would be fulfilled in different groups of stakeholders involved at the start of a process to implement ergonomic [corrected] measures in bricklaying teams. The measures include trestles, bricklaying scaffolds, mast climbing work platforms [corrected] and cranes. The behavioural change phases were: (1) being aware of measures, (2) understanding measures, (3) wanting measures, (4) intention to buy or hire measures, (5) ability to use measures, (6) using measures (experience), and (7) continuing to use measures. Structured interviews were conducted to examine the change phases in two groups of stakeholders (employers/work planners (n=11) [corrected] and foremen/bricklayers (n=9) [corrected] from nine companies) thought to be relevant in the decision to adopt and use the ergonomic [corrected] measures. The results show that the fulfilled behavioural change phases differ between individual stakeholders, groups of stakeholders, companies and also between ergonomic measures. The hypothesised order of fulfilled consecutive behavioural change phases for individual stakeholders has not been confirmed by this study. The relationship between [corrected] fulfilled and unfulfilled change phases by each stakeholder (group) and actual use of each ergonomic measure requires further study, so as to improve the selection of suitable implementation strategies [corrected]     

Controllability distributions and systems approximations: ageometric approach

Given a nonlinear system we determine a relation at an equilibrium between controllability distributions defined for a nonlinear system and a Taylor series approximation of it. The value of such a relation is appreciated if we recall that the solvability conditions as well as the solutions to some control synthesis problems can be stated in terms of geometric concepts like controlled invariant (controllability) distributions. The relation between these distributions at the equilibrium will help us to decide when the solvability conditions of this kind of problems are equivalent for the nonlinear system and its approximation     

承前启后发展荷兰整体性长期规划——专访荷兰住房、空间规划与环境部国土规划司司长汉克·欧文科

王秋元（以下简称W）：请您阐述您的主要工作内容与任务,以及您的工作任务与“兰斯塔德环型城市2040远景”（以下简称“2040远景”）的关系。     

Costs of mastitis: facts and perception

A model to calculate the economic losses of mastitis on an average Dutch dairy farm was developed and used as base for a tool for farmers and advisors to calculate farm-specific economic losses of mastitis. The economic losses of a clinical case in a default situation were calculated as euro210, varying from euro164 to euro235 depending on the month of lactation. The total economic losses of mastitis (subclinical and clinical) per cow present in a default situation varied between euro65 and euro182/cow per year depending on the bulk tank somatic cell count. The tool was used to measure perception of the total economic losses of mastitis on the farm and the farmers' assessment of the cost factors of mastitis on 78 dairy farms, of which 64 were used for further analyses. Most farmers (72%) expected their economic losses to be lower than those revealed by our calculation made with their farm information. Underestimating the economic losses of mastitis can be regarded as a general problem in the dairy sector. The average economic losses assessed by the farmers were euro78/cow per year, but a large variation was given, euro17-198/cow per year. Although the average assessment of the farmers of the different cost factors is close to the default value, there is much variation. To improve the adoption rate of advice and lower the incidence of mastitis, it is important to show the farmers the economic losses of mastitis on their farm. The tool described in this paper can play a role in that process.