The influence of sulphate-reducing bacteria biofilm on the corrosion of stainless steel AISI 316

This work investigates microbially-influenced corrosion (MIC) of stainless steel AISI 316 by two sulphate-reducing bacteria, Desulfovibrio desulfuricans and a local marine isolate. The biofilm and pit morphology that developed with time were analyzed using atomic force microscopy (AFM). Electrochemical impedance spectroscopy (EIS) results were interpreted with an equivalent circuit to model the physicoelectric characteristics of the electrode/biofilm/solution interface. D. desulfuricans formed one biofilm layer on the metal surface, while the marine isolate formed two layers: a biofilm layer and a ferrous sulfide deposit layer. AFM images corroborated results from the EIS modeling which showed biofilm attachment and subsequent detachment over time.     

Probabilistic simulation of fire scenarios

A risk analysis tool is developed for computation of the distributions of fire model output variables. The tool, called Probabilistic Fire Simulator (PFS), combines Monte Carlo simulation and CFAST, a two-zone fire model. In this work, the tool is used to estimate the failure probability of redundant cables in a cable tunnel fire, and the failure and smoke filling probabilities in an electronics room during an electronics cabinet fire. Sensitivity of the output variables to the input variables is calculated in terms of the rank order correlations. The use of the rank order correlations allows the user to identify both modelling parameters and actual facility properties that have the most influence on the results. Various steps of the simulation process, i.e. data collection, generation of the input distributions, modelling assumptions, definition of the output variables and the actual simulation, are described.     

Effects of Ospemifene on Drug Metabolism Mediated by Cytochrome P450 Enzymes in Humans in Vitro and in Vivo

The objective of these investigations was to determine the possible effects of the novel selective estrogen receptor modulator, ospemifene, on cytochrome P450 (CYP)-mediated drug metabolism. Ospemifene underwent testing for possible effects on CYP enzyme activity in human liver microsomes and in isolated human hepatocytes. Based on the results obtained in vitro, three Phase 1 crossover pharmacokinetic studies were conducted in healthy postmenopausal women to assess the in vivo effects of ospemifene on CYP-mediated drug metabolism. Ospemifene and its main metabolites 4-hydroxyospemifene and 4′-hydroxyospemifene weakly inhibited a number of CYPs (CYP2B6, CYP2C9, CYP2C19, CYP2C8, and CYP2D6) in vitro. However, only CYP2C9 activity was inhibited by 4-hydroxyospemifene at clinically relevant concentrations. Induction of CYPs by ospemifene in cultured human hepatocytes was 2.4-fold or less. The in vivo studies showed that ospemifene did not have significant effects on the areas under the plasma concentration-time curves of the tested CYP substrates warfarin (CYP2C9), bupropion (CYP2B6) and omeprazole (CYP2C19), demonstrating that pretreatment with ospemifene did not alter their metabolism. Therefore, the risk that ospemifene will affect the pharmacokinetics of drugs that are substrates for CYP enzymes is low.     

User problems with individual temperature control in offices

Individual thermal control is important for handling personal differences in thermal preference. Several studies have shown that comfort, health and productivity in offices can be improved by individual thermal control. Local controls for temperature are commonly available in modern office buildings. However, office occupants are often still dissatisfied with the thermal environment and their control options. In this study we used contextual techniques to gain an understanding of the user problems with individual temperature control. A total of 27 office occupants in 13 Finnish buildings were interviewed in their offices. They were asked to show and tell us how they use the controls. The results show that the temperature controls were often not used in thermal discomfort. A diversity of problems with individual temperature control was identified and are listed with proposed solutions. The main reason for the many of the problems is that systems are planned and constructed without a realistic view of their users, and end users are presumed to have knowledge they don’t have. The users should be studied and more effort should be put into user interface development.     

Breaking of window glass close to fire

A heat conduction equation with linerized radiation cooling boundary conditions is used to calculate the thermal field in a long-strip window pane heated by thermal radiation (fire), except on narrow strips along edges built into the frame. This temperature field is used to calculate a quasi-static thermal stress field in the pane in the first-order planar stress approximation. Derived analytic equations of stresses are presented graphically. Thermal stresses build up at the edges in a narrow strip of a few times the pane thickness. In cool spots of the order of 100 K lower than the average temperature, stress build-up can cause a microcrack to become a fast-propagating fracture.     

Dust formed during drilling in natural stone quarries

Bulletin of Engineering Geology and the Environment - Dust mass concentration and concentration decrease was studied in two natural stone quarries in Finland. The dust mass concentrations produced...     

Analysis of EMG and acceleration signals for quantifying the effects of deep brain stimulation in Parkinson's disease

Deep brain stimulation (DBS) is effective in reducing motor symptoms in Parkinson's disease (PD). However, objective methods for quantifying its efficacy are lacking. We present a principal component (PC)-based tracking method for quantifying the effects of DBS in PD by using electromyography (EMG) and acceleration measurements. Ten parameters capturing PD characteristic signal features were initially extracted from isometric EMG and acceleration recordings. Using a PC approach, the original parameters were transformed into a smaller number of PCs. Finally, the effects of DBS were quantified by examining the PCs in a low-dimensional feature space. The EMG and acceleration data from 13 PD patients with DBS ON and OFF, and 13 healthy age-matched controls were used for analysis. Clinical evaluation of patients showed that their motor symptoms were effectively reduced with DBS. The analysis results showed that the signal characteristics of 12 patients were more similar to those of the healthy controls with DBS ON than with DBS OFF. These observations indicate that the PC-based tracking method can be used to objectively quantify the effects of DBS on the neuromuscular function of PD patients. Further studies are suggested to estimate the clinical sensitivity of the method to different types of PD.     

Behaviour of Coal associated Minerals during Coking and Blast Furnace Processes – a Review

Metallurgical coke is made from a mix of several types of coal that contain various minerals, including quartz, carbonates, feldspars, sulphides and a number of phyllosilicates, represented by clay minerals and micas. During coking and coke consumption processes the minerals undergo various physical and chemical changes, which in the case of coke oven batteries include desulphurization, decarbonation, dehydration, dehydroxylation, polymorph transformations, melting with the formation of an alkali and silica‐rich liquid, and transformation to another crystalline phase. The typical modifications of mineral phases in a blast furnace (BF) coke are polymorph transformations, melting, and the formation of another crystalline phase. These events are also preceded by notable changes in the shape of crystalline aggregates. All these changes affect the coke properties and the processes occurring in a BF. Mineralogical data can help us to better understand the processes taking place in coke batteries and in a BF, and to improve the quality of a coke by more careful selection of coal blends and setting optimal temperatures for its pre‐heating. The degradation of a BF coke by alkalis can be reduced by the addition of certain minerals to the feed coke before charging into the BF.     

Effects of formulation and processing variables on dry fish feed pellets containing fish waste

A low-cost preparation process starting from fish waste, pregelatinised wheat flour and soya flour was optimised with regard to the physical properties of the pellets, by using response surface modelling. Independent variables were the ratio of wheat flour to soya flour, quantity of added water, temperature of added water, and mixing time. Pellet quality attributes measured for each set of variables were bulk density, water absorption index, sinking velocity, residual moisture, and structural integrity in water. Mixing time played the most important role among the input variables in defining pellet quality. The results suggest that a dry fish feed pellet of good quality can be manufactured by a simple pressing method using a mixture of 50% fish waste, 30–35% pregelatinised wheat flour, and 15–20% soya meal mixed with water (30-35% of the sum of other ingredients) of 60–65°C for 4–5 min. A method for determining structural integrity of pellets in turbulent water is presented.