3-D density model of the crust of southern and central Finland obtained from joint interpretation of the SVEKALAPKO crustal P-wave velocity models and gravity data

Peer reviewe

Numerical modeling and inversion of geophysical electromagnetic measurements using a thin plate model

Abstract The thesis deals with numerical methods designed for the modeling and inversion of geophysical electromagnetic (EM) measurements using a conductive thin plate model. The main objectives are to study the EM induction problem in general and to develop practical interpretation tools for mineral prospecting in particular. The starting point is a linearized inversion method based on the singular value decomposition and a new adaptive damping method. The inversion method is introduced to the interpretation of time-domain EM (TEM) measurements using a thin plate in free-space. The central part of the thesis is a new approximate modeling method, which is based on an integral equation approach and a special lattice model. At first the modeling method is applied to the interpretation of frequency-domain EM (FEM) data using a thin plate in conductive two-layered earth. After this time-domain responses are modeled applying a Fourier-sine transform of broadband FEM computations. The results demonstrate that the approximate computational method can model the geophysical frequency and time-domain EM responses of a thin conductor in conductive host medium with sufficient accuracy, and that the inversion method can provide reliable estimates for the model parameters. The fast forward computation enables interactive interpretation of FEM data and feasible forward modeling of TEM responses. The misfit function mapping and analysis of the singular value decomposition have provided additional information about the sensitivity, resolution, and the correlation behavior of the thin plate parameters

Perception of Difficulties Encountered in Eating Process from European Elderlies' Perspective

To maintain wellbeing, independence and nourishment of elderly population, one promising strategy is to provide home care by delivering food using “meals on wheels” (MoW) system. Even when the food is home-delivered, the difficulties encountered by elderlies during the overall eating process can be a limiting factor. Hence, the objective of this self-reported study was to explore the difficulty perception in the entire eating process from opening up the package, reheating, hand manipulation and oral processing of the food to bolus swallowing in 405 elderly consumers from five European countries (Finland, France, Poland, Spain and United Kingdom) with three different levels of dependency (category 1: participants living at home with help needed for food purchasing; category 2: participants living at home who need help for meal preparation or meal delivery; category 3: participants living in nursing homes/sheltered accommodation). Frequencies of responses and cross tabulation test were calculated for the difficulties perceived. Results show that the most difficult package to open was the cap irrespective of country or dependency levels (at P < 0.05). Although, glass was the most preferred packaging material, category (P = 0.034) and country (P = 0.001) had significant influence. Self-feeding dependency was correlated with the eating difficulties perceived, category 1 participants did not perceive difficulties in the meal preparation and reported minimal difficulties in the hand manipulation and oral processing (<30%), whilst the difficulties perceived by categories 2 and 3 were significantly higher (∼60% of participants). The insights generated might be helpful for designing efficient MoW systems with appropriate user-friendly features

Fruit and vegetables liking among European elderly according to food preferences, attitudes towards food and dependency

As the population ages and dependency for food-related activities increases, it becomes crucial to better understand food expectations of elderly consumers. Fruit and vegetables (F&V) are generally appreciated by elderly people. However, few studies have investigated elderly peoples’ F&V liking, taking into account their dependency and countries’ specificities. The present study aims to identify the liking of F&V, eating styles and food selectivity depending on the country of residence and levels of dependency. A European survey was conducted with 420 elderly people delegating meal-related activities, living at home or in nursing homes. Based on general food preferences, three eating styles were identified. Results showed that F&V liking is a segmenting variable. Elderly people from the style 1 (n = 145) do not really appreciate fruits nor desserts. On the contrary, elderly people from style 2 (n = 121) are really fruit lovers. Finally, elderly people from style 3 (n = 126) liked desserts, fruits, and even more vegetables. Results showed that elderly people were nor selective towards F&V, even if there were some exceptions as exotic fruits (disliked by 19%) and fennel (disliked by 33%). Fruit and vegetables selectivity was significantly different between countries (p 0.05 in both cases). Selectivity for F&V was very variable and could reach 32 vegetables among 42 and 28 fruits among 34. The most selective participants were from Finland and the least ones, from the UK. These results can be used to design and/or adapt F&V-based products according to elderly consumers’ liking, taking into account their country of origin and their dependency

Metabolic capacities and toxigenic potential as key drivers of Bacillus cereus ubiquity and adaptation

Bacillus cereus is ubiquitous and commonly found in a wide range of environments,including food. In this study, we analysed 114 foodborne B. cereus strains isolated mainly from starchy and dairy products in order to investigate their phenotypic diversity (API system), antimicrobial resistance and toxigenic profiles (hblA, nheA, hlyII,cereolysin O, cytK2, cytK1 and EM1 genes). All isolates were confirmed as B. cereus using 16S-23S ribosomal DNA intergenic transcribed spacers (ITS) signature. They were shown as Gram-positive, catalase and caseinase positive, haemolytic (97%), and positive for lecithin hydrolysis and motility (97 and 87 %, respectively). PCR detection of the B. cereus specific toxin genes revealed the occurrence rates of 100 % for cereolysin O, 98 % for nheA, 74 % for cytk2, 52 % for hblA, 28 % for hlyII, and the absence of cytK1. Only two strains (1.75%), isolated from intestine of boar and pheasant, carried the emetic toxin genetic determinants (ces). Antimicrobial susceptibility of isolates was tested towards 15 different antimicrobial agents. We detected susceptibility of all strains to most antibiotics, intermediate resistance to clindamycin and resistance to β lactam antibiotics with 83% of the resistant isolates producing β lactamase enzyme. This large phenotypic diversity combined with the toxigenic traits and antibiotic resistance; emphasize the high potential risk of food poisoning of B. cereus isolates. Beside, a clear correlation between the metabolic features and the origin of isolation was shown. Most of starchy isolates were able to hydrolyse starch while dairy strains were not able to produce amylases. Our overall results point out that the metabolic flexibility and toxigenic potential represent the main drivers for B. cereus ubiquity and adaptation in a given ecological nich