Influence of heat treatment on the sensory and physical characteristics and carbohydrate fractions of french-fried potatoes (Solanum tuberosum L.)

AbstractThe aim of this study was to analyze the impact that heat treatment with salts and freezing processes on the sensory, instrumental, and physico-chemical characteristics of fried potatoes of the Monalisa cultivar. The potatoes were blanched in distilled water (P); sodium chloride solution (B1); calcium chloride solution (B2), and a solution with both of these salts (B3). They were then pre-cooked and frozen for 24 hours and for 30 days. After frying, sensory characteristics were analyzed (color, texture, flavor, oiliness), along with overall preference and instrumental determinations of texture, color, and oil content. Further tests were conducted on the sample with the best results in the sensory analysis (B1), along with sample P as a control, to determine granule microstructure, carbohydrate fractions, glycemic index, and glycemic load. Blanching B3, despite reducing oil absorption and providing less oiliness, obtained lesser overall preference. Freezing for 30 days increased the lightness, except for when sodium chloride was used, which intensified the color yellow. The use of sodium chloride did not interfere with the type of starch granules, nor with the formation of resistant starch; however, longer freezing time reduced the glycemic index and concentrated the dietary fiber content. All samples exhibited low glycemic index and moderate glycemic loads.

Effect of ultrasound treatment on quality and microbial load of carrot juice

Effect of ultrasound treatment on carrot juice was investigated through measuring pH, electrical conductivity, viscosity, visual color, total soluble solids, total sugars, total carotenoids, ascorbic acid contents and microbial load. No significant effect (p>0.05) of ultrasound treatment on pH of carrot juice was observed. Electrical conductivity, viscosity and color values gradually increased (p<0.05) with treatment time increase. Total soluble solids, total sugars, total carotenoids and ascorbic acid contents of carrot juice were significantly improved (p<0.05) due to ultrasound treatment. Moreover, significant decrease (p<0.05) in microbial load of sonicated carrot juice was observed. Results from present study suggested that ultrasound treatment could improve quality and safety of carrot juice.

Modelling of changes in electricity end-use and their impacts on electricity distribution

The electricity distribution sector will face significant changes in the future. Increasing reliability demands will call for major network investments. At the same time, electricity end-use is undergoing profound changes. The changes include future energy technologies and other advances in the field. New technologies such as microgeneration and electric vehicles will have different kinds of impacts on electricity distribution network loads. In addition, smart metering provides more accurate electricity consumption data and opportunities to develop sophisticated load modelling and forecasting approaches. Thus, there are both demands and opportunities to develop a new type of long-term forecasting methodology for electricity distribution. The work concentrates on the technical and economic perspectives of electricity distribution. The doctoral dissertation proposes a methodology to forecast electricity consumption in the distribution networks. The forecasting process consists of a spatial analysis, clustering, end-use modelling, scenarios and simulation methods, and the load forecasts are based on the application of automatic meter reading (AMR) data. The developed long-term forecasting process produces power-based load forecasts. By applying these results, it is possible to forecast the impacts of changes on electrical energy in the network, and further, on the distribution system operator’s revenue. These results are applicable to distribution network and business planning. This doctoral dissertation includes a case study, which tests the forecasting process in practice. For the case study, the most prominent future energy technologies are chosen, and their impacts on the electrical energy and power on the network are analysed. The most relevant topics related to changes in the operating environment, namely energy efficiency, microgeneration, electric vehicles, energy storages and demand response, are discussed in more detail. The study shows that changes in electricity end-use may have radical impacts both on electrical energy and power in the distribution networks and on the distribution revenue. These changes will probably pose challenges for distribution system operators. The study suggests solutions for the distribution system operators on how they can prepare for the changing conditions. It is concluded that a new type of load forecasting methodology is needed, because the previous methods are no longer able to produce adequate forecasts.

Effect of loading type on the fatigue strength of symmetric and asymmetric welded joints made of ultra high strength steel

In this study, finite element analyses and experimental tests are carried out in order to investigate the effect of loading type and symmetry on the fatigue strength of three different non-load carrying welded joints. The current codes and recommendations do not give explicit instructions how to consider degree of bending in loading and the effect of symmetry in the fatigue assessment of welded joints. The fatigue assessment is done by using effective notch stress method and linear elastic fracture mechanics. Transverse attachment and cover plate joints are analyzed by using 2D plane strain element models in FEMAP/NxNastran and Franc2D software and longitudinal gusset case is analyzed by using solid element models in Abaqus and Abaqus/XFEM software. By means of the evaluated effective notch stress range and stress intensity factor range, the nominal fatigue strength is assessed. Experimental tests consist of the fatigue tests of transverse attachment joints with total amount of 12 specimens. In the tests, the effect of both loading type and symmetry on the fatigue strength is studied. Finite element analyses showed that the fatigue strength of asymmetric joint is higher in tensile loading and the fatigue strength of symmetric joint is higher in bending loading in terms of nominal and hot spot stress methods. Linear elastic fracture mechanics indicated that bending reduces stress intensity factors when the crack size is relatively large since the normal stress decreases at the crack tip due to the stress gradient. Under tensile loading, experimental tests corresponded with finite element analyzes. Still, the fatigue tested joints subjected to bending showed the bending increased the fatigue strength of non-load carrying welded joints and the fatigue test results did not fully agree with the fatigue assessment. According to the results, it can be concluded that in tensile loading, the symmetry of joint distinctly affects on the fatigue strength. The fatigue life assessment of bending loaded joints is challenging since it depends on whether the crack initiation or propagation is predominant.

Minkä nuorena hallitsee sen aikuisena taitaa? Liikehallinnan pysyvyys kouluiästä aikuisikään – 24 vuoden seurantatutkimus

Tässä 24 vuoden pitkittäistutkimuksessa tutkitaan liikehallinnan kehitystä ja pysyvyyttä kouluiästä aikuisikään. Lisäksi ennustetaan ja selitetään aikuisiän liikehallintaa kouluiän liikehallinnan perusteella. Tutkimukseen osallistui 44 miestä ja 44 naista eri puolilta Suomea, joiden liikehallintaa mitattiin kouluiässä 1985 ja 1988 (9–16-vuotiaina) sekä aikuisiässä 2009 (33−39-vuotiaina). Liikehallintaa mitattiin kuudella liiketehtävämittarilla (flamingoseisonta, tarkkuusheittokiinniotto, kahdeksikkokuljetus, edestakaisinhyppely, vauhditon 5-loikka ja kärrynpyörä) sekä niistä lasketulla summamuuttujalla. Miesten ja naisten liikehallintaa vertailtiin varianssianalyysilla. Kouluiässä pojat menestyivät välineenkäsittelytehtävissä ja tytöt tasapaino- ja voimistelutehtävissä, mutta kokonaisuutena sukupuolten välillä ei ollut eroa. Aikuisena miehet olivat naisia parempia lähes kaikissa tehtävissä. Kovarianssianalyysissä havaittiin, että kehonrakenteeltaan (BMI) erilaisten ryhmien liikehallinnassa oli vain yksittäisiä eroja koulu- ja aikuisiässä. Toistettujen mittausten varianssianalyysissa ilmeni, että kouluiässä molempien sukupuolten liikehallinnan kehitys oli samanlaista. Kouluiän jälkeen kevyiden ja keskipainoisten poikien liikehallinta parani, mutta painavien tulokset eivät muuttuneet. Kevyiden tyttöjen tuloksissa ei tapahtunut muutosta, mutta keskipainoisten ja painavien tulokset heikkenivät. Koululiikunnan tehostus- ja vertailuryhmien välille kouluiässä muodostuneet erot kaventuivat tai katosivat aikuisena. Kouluiän liikehallinnaltaan eritasoisten ryhmien väliset erot kaventuivat, mutta eivät poistuneet kouluiän jälkeen. Klusterianalyysissa tutkittavat jakaantuivat kouluiässä neljään liikehallintatyyppiin (yleishyvät, tasapainoiset, pallotaitajat ja yleisheikot), jotka säilyivät myös aikuisiässä, mutta niiden väliset erot kaventuivat. Ristiintaulukointi ja khiin neliö -testi osoittivat, että tasoryhmän ja liikehallinnan monipuolisuuden pysyvyys oli vahvaa kouluiästä aikuisikään. Koulu- ja aikuisiän liikehallintatulosten välinen korrelaatio oli naisilla (0.69) vahvempaa kuin miehillä (0.48). Yksittäiset mittaustulokset kouluiässä selittivät keskimäärin 33 % aikuisiän tuloksista (korrelaation neliö). Regressioanalyysissa miesten aikuisiän liikehallintaa selittivät kouluiän muuttujista parhaiten liikehallinnan monipuolisuus sekä liikkuvuus (61 %), mutta naisilla vain liikehallinnan monipuolisuus (37 %). Miesten ja naisten erot liikehallinnassa syntyivät kouluiän jälkeen, mikä johtunee erilaisista liikuntatavoista ja -harrastuksista. Kouluiän liikehallinta määritti vahvasti varsinkin tytöillä aikuisiän liikehallintaa sekä yksilö- että ryhmätasolla, mikä korostaa monipuolisen koululiikunnan merkitystä. Yksilölliset muutokset olivat mahdollisia. Kouluiän jälkeen erityisesti naiset ja kehonrakenteeltaan painavat tarvitsisivat hermolihasjärjestelmää monipuolisesti kuormittavaa ja liikesuunniltaan moniulotteista liikuntaa liikehallinnan kehittämiseksi ja ylläpitämiseksi. Naisten liikehallinnan taantuminen varsinkin tasapainotehtävissä voi altistaa kaatumistapaturmille ja rajoittaa fyysistä toimintakykyä.

Convenience of scallops in plate structures

In this thesis was performed comprehensive study about the convenience of scallops in plate structures. A literature review was performed and lack of knowledge was fulfilled with fatigue tests performed in the laboratory of Steel Structures at the Lappeenranta University of Technology and with finite element method. The aim of this thesis was to produce design guidance for the use of scallops for different structural details and different loading conditions. An additional aim was to include more precise instructions for scallop design to produce good fatigue resistance and appropriate manufacturing quality. The literature review was performed searching bridge engineering and maritime standards and design guides and studies from scientific databases and reference lists from the literature of this field. Fatigue tests were used to research the effect of using scallops or not using scallops to fatigue strength of bracket specimen. Tests were performed on three specimens with different scallop radii and to five specimens without scallops with different weld penetration depths. Finite element method using solid elements, symmetry and submodels was used to determine stress concentration factors for I-beams with scallops. Stresses were defined with hot spot stress method. Choosing to use a scallop or not in the structure is affected by many factors, such as structural and loading conditions and manufacturability. As a rule of thumb, scallops should be avoided because those cause stress concentration points to the structure and take a lot of time to manufacture. When scallops are not used, good quality welding should be provided and full weld penetration is recommended to be used in load carrying corner weld areas. In some cases, it is advisable to use scallops. In that case, circular scallops are recommended to be used and radius should be chosen from fatigue strength or manufacturing point of view.

Ultralujan teräksen kaarijuotto

Tässä diplomityössä tutkitaan ultralujan rakenneteräksen kaarijuotolla valmistettujen liitosten väsymiskestävyyttä. Tutkittavat liitokset ovat kuormaa kantamattomia X-liitoksia. Tutkinnassa vertaillaan puhtaasti juottamalla valmistettua liitosta hitsauksen ja juoton kombinaatioliitokseen, jossa pohjapalkona toimivan hitsin rajaviivalle on juotettu lisäpalko. Kaarijuottoa esitellään yleisesti liittämismenetelmänä. Ultralujaa rakenneterästä esitellään yleisesti ja tarkastellaan sen metallurgista käyttäytymistä sekä juotettaessa, että hitsattaessa. Tutkimuksessa tehtiin kaikkiaan 21 väsytystestiä. Väsytystestit muodostuivat kolmesta eri koekappalesarjasta. Ensimmäisen ja toisen sarjan koekappaleet tehtiin juottamalla, eri lisäaineilla. 3. sarjassa pienat hitsattiin, jonka jälkeen hitsin rajaviivalle tehtiin juotto. Kappaleiden geometriat mitattiin ennen testejä, ja osasta kappaleista mitattiin jäännösjännitykset. Kappaleista otettiin hieitä, joista tehtiin kovuusmittaukset ja suoritettiin makro- ja mikrotason tarkastelua liitosprosessin lämmöntuonnin vaikutuksesta. Väsytyskokeiden perusteella kappaleille määritettiin nimelliset ja rakenteelliset väsymisluokat. Tuloksista piirrettiin S-N –käyrät. Liitoksista tehtiin FEA-mallit, joista määritettiin liitoksen rajaviivalle muodostuva jännitys ja 2. sarjan koekappaleiden laskennalliset kestoiät. 1. sarjan juotoksissa oli ongelmana juotoksen tarttuvuus teräksen pintaan. 2. sarjan koetulokset olivat kaikkein parhaita. 3. sarjan kombinaatioliitokset ylsivät kohtalaisiin väsymisluokkiin. 2. sarjan koetulosten perusteella kaarijuotossa on potentiaalia ultralujan rakenneteräksen liittämismenetelmänä. Jatkotutkimuksen tarve on kuitenkin laaja. Tämä työ osoitti, että kaarijuottaminen voi olla vaativa liittämisprosessi, sillä toimiakseen se vaatii varsin tarkat parametrit, ja lisäksi prosessi on melko herkkä olosuhdemuutoksille.

Standardized electrical tests for electrical equipment in road vehicles Case: Visedo Oy PowerMASTER M-frame

Electrical road vehicles were common at the begin of the 20th century but internal combustion engines took a victory from electrical motors in road vehicles. The acknowledgement of the environment, and the price and the availability of the crude oil are reasons for the comeback of the electrical vehicles. Advancement in industrial technology and political atmosphere in EU as the directive 20--20--20, which consists of reducing fossil emission, increasing renewable energy and increasing the energy efficiency, have made the electrification popular again. In this thesis tests based on standard ISO 16750--2 electrical loads for electrical equipment in road vehicles are made for Visedo Oy's PowerMASTER M-frame power electronics device. This device is designed for mainly drive trains in mobile work machines and marine vessels but can be used in other application in its power range which also includes road vehicles. The functionality of the device is tested with preliminary tests which act as a framework for the tests based on standards.

The effect of diet and parasite load on female phonotaxis in the Texas field cricket, Gryllus integer

Female crickets respond selectively to variations in species-specific male calling songs. This selectivity has been shown to be age-dependent; older females are less choosy. However, female quality should also affect female selectivity. The effect of female quality on mate choice was examined in Gryllus integer by comparing the phonotactic responses of females on different diets and with different parasite loads to various synthetic models of conspecific calling song. Test females were virgin, 11-14 days old, and had been maintained on one of five diets varying in protein and fat content. Phonotaxis was quantified using a non-compensating Kugel treadmill which generates vector scores incorporating the speed and direction of movement of each female. Test females were presented with four calling song models which differed in pulse rate, but were still within the natural range of the species for the experimental temperature. After testing, females were dissected and the number of gregarine parasites within the digestive tract counted. There were no significant effects of either diet or parasitism on female motivation to mate although the combined effects of these variables seem to have an effect with no apparent trend. Control females did not discriminate among song types, but there was a trend of female preferences for lower pulse rates which are closest to the mean pulse rate for the species. Heavily parasitized females did not discriminate among pulse rates altho~gh there was a similar trend of high vector scores for low pulse rates. Diet, however, affected selectivity with poorly-fed females showing significantly high vector scores for pulse rates near the species mean. Such findings raise interesting questions about energy allocation and costs and risks of phonotaxis and mate choice in acoustic Orthoptera. These results are discussed in terms of sexual selection and female mate choice.

Electrocortical indices of cognitive control in working memory : exploring the effects of proactive interference, cognitive load, and aging

Cognitive control involves the ability to flexibly adjust cognitive processing in order to resist interference and promote goal-directed behaviour. Although frontal cortex is considered to be broadly involved in cognitive control, the mechanisms by which frontal brain areas implement control functions are unclear. Furthermore, aging is associated with reductions in the ability to implement control functions and questions remain as to whether unique cortical responses serve a compensatory role in maintaining maximal performance in later years. Described here are three studies in which electrophysiological data were recorded while participants performed modified versions of the standard Sternberg task. The goal was to determine how top-down control is implemented in younger adults and altered in aging. In study I, the effects of frequent stimulus repetition on the interference-related N450 were investigated in a Sternberg task with a small stimulus set (requiring extensive stimulus resampling) and a task with a large stimulus set (requiring no stimulus resampling).The data indicated that constant stimulus res amp ling required by employing small stimulus sets can undercut the effect of proactive interference on the N450. In study 2, younger and older adults were tested in a standard version of the Sternberg task to determine whether the unique frontal positivity, previously shown to predict memory impairment in older adults during a proactive interference task, would be associated with the improved performance when memory recognition could be aided by unambiguous stimulus familiarity. Here, results indicated that the frontal positivity was associated with poorer memory performance, replicating the effect observed in a more cognitively demanding task, and showing that stimulus familiarity does not mediate compensatory cortical activations in older adults. Although the frontal positivity could be interpreted to reflect maladaptive cortical activation, it may also reflect attempts at compensation that fail to fully ameliorate agerelated decline. Furthermore, the frontal positivity may be the result of older adults' reliance on late occurring, controlled processing in contrast to younger adults' ability to identify stimuli at very early stages of processing. In the final study, working memory load was manipulated in the proactive interference Sternberg task in order to investigate whether the N450 reflects simple interference detection, with little need for cognitive resources, or an active conflict resolution mechanism that requires executive resources to implement. Independent component analysis was used to isolate the effect of interference revealing that the canonical N450 was based on two dissociable cognitive control mechanisms: a left frontal negativity that reflects active interference resolution, , but requires executive resources to implement, and a right frontal negativity that reflects global response inhibition that can be relied on when executive resources are minimal but at the cost of a slowed response. Collectively, these studies advance understanding of the factors that influence younger and older adults' ability to satisfy goal-directed behavioural requirements in the face of interference and the effects of age-related cognitive decline.

The Reluctance of Cattle to Change a Learned Choice May Confound Preference Tests

The conclusion of the article states "it appears that previously learned choices may affect future choices in Y-mazes for cattle. Another area that needs to be researched is the effects of a mildly aversive treatment versus a severely aversive treatment on the tendency of a bovine to resist changing a learned choice".

Simulation-Based Finite and Large Sample Tests in Multivariate Regressions.

In the context of multivariate linear regression (MLR) models, it is well known that commonly employed asymptotic test criteria are seriously biased towards overrejection. In this paper, we propose a general method for constructing exact tests of possibly nonlinear hypotheses on the coefficients of MLR systems. For the case of uniform linear hypotheses, we present exact distributional invariance results concerning several standard test criteria. These include Wilks' likelihood ratio (LR) criterion as well as trace and maximum root criteria. The normality assumption is not necessary for most of the results to hold. Implications for inference are two-fold. First, invariance to nuisance parameters entails that the technique of Monte Carlo tests can be applied on all these statistics to obtain exact tests of uniform linear hypotheses. Second, the invariance property of the latter statistic is exploited to derive general nuisance-parameter-free bounds on the distribution of the LR statistic for arbitrary hypotheses. Even though it may be difficult to compute these bounds analytically, they can easily be simulated, hence yielding exact bounds Monte Carlo tests. Illustrative simulation experiments show that the bounds are sufficiently tight to provide conclusive results with a high probability. Our findings illustrate the value of the bounds as a tool to be used in conjunction with more traditional simulation-based test methods (e.g., the parametric bootstrap) which may be applied when the bounds are not conclusive.

Exact Tests for Contemporaneous Correlation of Disturbances in Seemingly Unrelated Regressions.

This paper proposes finite-sample procedures for testing the SURE specification in multi-equation regression models, i.e. whether the disturbances in different equations are contemporaneously uncorrelated or not. We apply the technique of Monte Carlo (MC) tests [Dwass (1957), Barnard (1963)] to obtain exact tests based on standard LR and LM zero correlation tests. We also suggest a MC quasi-LR (QLR) test based on feasible generalized least squares (FGLS). We show that the latter statistics are pivotal under the null, which provides the justification for applying MC tests. Furthermore, we extend the exact independence test proposed by Harvey and Phillips (1982) to the multi-equation framework. Specifically, we introduce several induced tests based on a set of simultaneous Harvey/Phillips-type tests and suggest a simulation-based solution to the associated combination problem. The properties of the proposed tests are studied in a Monte Carlo experiment which shows that standard asymptotic tests exhibit important size distortions, while MC tests achieve complete size control and display good power. Moreover, MC-QLR tests performed best in terms of power, a result of interest from the point of view of simulation-based tests. The power of the MC induced tests improves appreciably in comparison to standard Bonferroni tests and, in certain cases, outperforms the likelihood-based MC tests. The tests are applied to data used by Fischer (1993) to analyze the macroeconomic determinants of growth.