Elämäntapatutkimus kauneudenhoitoalan opiskelijoille

Tämän opinnäytetyön tarkoitus on selvittää kauneudenhoitoalan opiskelijoiden elämäntapoja ja analysoida niiden vaikutuksia koulussa jaksamiseen sekä opintojen etenemiseen. Opinnäytetyö on tehty yhteistyössä Stadin ammattiopiston kauneudenhoitoalan koulutusyksikön kanssa. Tutkimuksen tavoite on tuoda esille elämäntapojen vaikutus opintoihin, ja mahdollisesti saada nuoret opiskelijat ymmärtämään valintojensa merkitys. Elämäntavat näkyvät väistämättä jokaisen ihmisen arjessa, ja nuorena opitut tavat jatkuvat monesti myös aikuisiällä. Asioiden merkitys on hyvä ymmärtää jo nuorena rakennettaessa tulevaisuutta kouluttautumalla työelämään. Tutkimuksessa kävi ilmi, että elämäntavat vaikuttavat nuorten opintoihin tutkimustulosten perusteella vähemmän kuin ennakko-oletuksena oli. Vastausten mukaan kauneudenhoitoalan opiskelijoiden elämäntavat ovat melko hyvät, eikä heillä juurikaan ole poissaoloja koulusta huonojen elintapojen seurauksena. Kuitenkin esille nousi se, että mikäli poissaoloja koulusta on kertynyt, vaikuttaa se opiskelumotivaatioon ja opintojen etenemiseen. Päällimmäisenä tutkimuksessa nousi esille, että selkein syy poissaoloihin vaikuttaisi tutkimuksen mukaan olevan unenpuute, jota esiintyi noin puolella vastaajista. Suurimmalla osalla opiskelijoista ei ole säännöllistä vuorokausirytmiä, vaikka opiskelu tapahtuu arkipäivisin samaan aikaan. Unen määrän ja laadun koetaan myös vaikuttavan opinnoissa jaksamiseen. Noin puolella vastaajista ei myöskään ole säännöllistä ruokailurytmiä, mutta sen ei koeta kuitenkaan juurikaan vaikuttavan opintoihin negatiivisesti. Tutkimuksen tuloksia voidaan hyödyntää ammatillisissa oppilaitoksissa, kun pyritään ymmärtämään opiskelijoiden opinnoissa jaksamisen syitä sekä opiskelumotivaatiota.Survey of lifestyle habits among beauty care students The purpose of this thesis was to survey the beauty care students’ lifestyle habits and analyse the effects of those habits on the students’ well-being and performance at school. The thesis was done in cooperation with Helsinki Vocational College. The aim of this study was to find out how lifestyle habits affect the studies and hopefully make the young students understand the implications of their choices. The lifestyle choices have a great impact on how we live and the habits adopted early are often carried into adulthood. The significance of one’s choices is important to take into account when getting ready for the future job market. According to the results of this study, lifestyle habits affect the students’ performance less than was assumed. The results showed that the beauty care students’ lifestyle habits are quite good and they did not have many lifestyle related absences from classes. Yet, when absences pile up, it implies problems concerning motivation and advancement in studies. The main finding was that the most common reason for absences is sleep deprivation, which was experienced by half of the students who participated in this study. The majority of the students did not have a regular daily rhythm even though they studied daily at regular times. The quantity and quality of sleep were seen as affecting the studies. About half of the respondents did not have a regular dietary schedule either, but it was not seen as affecting the studies negatively. The results of this study can be used at vocational colleges when trying to understand the issues related to the students’ performance and motivation in studies

Evaluation of extensional and torsional stiffness of single actin filaments by molecular dynamics analysis.

It is essential to investigate the mechanical behaviour of cytoskeletal actin filaments in order to understand their critical role as mechanical components in various cellular functional activities. These actin filaments consisting of monomeric molecules function in the thermal fluctuations. Hence, it is important to understand their mechanical behaviour on the microscopic scale by comparing the stiffness based on thermal fluctuations with the one experimentally measured on the macroscopic scale. In this study, we perform a large-scale molecular dynamics (MD) simulation for a half-turn structure of an actin filament. We analyse its longitudinal and twisting Brownian motions in equilibrium and evaluated its apparent extensional and torsional stiffness on the nanosecond scale. Upon increasing the sampling-window durations for analysis, the apparent stiffness gradually decreases and exhibits a trend to converge to a value that is close to the experimental value. This suggests that by extrapolating the data obtained in the MD analysis, we can estimate the experimentally determined stiffness on the microsecond to millisecond scales. For shorter temporal scales, the apparent stiffness is larger than experimental values, indicating that fast, local motions of the molecular structure are dominant. To quantify the local structural changes within the filament on the nanosecond scale and investigate the molecular mechanisms, such as the binding of the actin-regulatory proteins to the filaments, it is preferable to analyse the mechanical behaviour on the nanometre and nanosecond scales using MD simulation

Kannattavuuden arviointi yksityismetsätaloudessa

Opinnäytetyön tavoitteena oli kannattavuuden arviointi esimerkkitilalla metsätalouden ohjelmistoja hyödyntäen ja arvioida ohjelmistojen soveltuvuutta yksityismetsätalouden käyttöön. Työn teoriaosuuteen perehdyttiin tutustumalla Suomen metsävaroihin ja metsänomistajarakenteeseen. Met-sätalouden kannattavuuden perustana olivat teoriapohja liittyen metsätalouden tuloihin, menoihin ja verotukseen. Työssä aineistona käytettiin vuonna 2015 laadittua metsäsuunnitelmaa. Tutkimusmenetelminä olivat esimerkkitilan kannattavuuden arviointi Metsätalouden kannattavuuslaskuria ja Motti-ohjelmistoa hyödyntäen. Metsätalouden kannattavuuslaskurin avulla laadittiin yhteenveto metsätilan taloudellisista tunnusluvuista, taselaskelmasta, tuloslaskelmasta ja kassavirran kehityksestä. Motti-ohjelmistolla laadittiin esimerkkitilan edustaville kuvioille kehitysennusteet ja selvitettiin erilaisten metsänkäsittelytoimenpiteiden taloudellista kannattavuutta. Keskimääräinen liiketulos metsätilalla oli 10 073 euroa vuodessa. Metsätilan hehtaarikohtainen liiketulos oli 45 euroa vuodessa. Metsätilan kirjanpidon tulos säilyi positiivisena lukuun ottamatta tarkastelujakson viimeistä vuotta, jolle ei ajoittunut metsäsuunnitelman mukaisia hakkuita. Esimerkkitilalla kannattavuutta voitaisiin parantaa tekemällä osa metsänhoitotöistä omatoimisesti ostopalvelun sijasta. Metsätalouden kannattavuuslaskurin todettiin soveltuvan kannattavuuden tarkasteluun tilatasolla. Metsätalouslaskurin edellyttämä metsäsuunnitelma mahdollistaa mahdollisimman luotettavan kannattavuuden arvioinnin. Epävarmuustekijöinä laskelmissa on rahavirtojen perustuminen pitkän ajan indekseihin. Motti-ohjelmisto soveltuu erilaisten metsänkäsittelyvaihtoehtojen vertailuun ja niistä aiheutuvien kustannusten arviointiin kuviotasolla. Motti-ohjelman epävarmuustekijänä on puuttuva mahdollisuus simuloida luonnon tai ihmisten aiheuttamien tuhojen vaikutusta metsikön kasvuun.The purpose of this thesis was to estimate profitability in a certain forest holding using silvicultural softwares and evaluate their suitability for use in forestry. The theory part handles Finnish forest resources and forest ownership structure. The profitability of forest holdings was based on the theory in incomes, expenses and taxes. The material for the thesis was a forest management plan that was made in 2015. The thesis consisted of the evaluation of the profitability in one forest holding using a profitability calculation programme and Motti-software. With the profitability calculation programme a summary of the financial figures, balance sheets, income statements and cash flow developments in forest holdings was done. Motti-software was used to make development predictions in the representative compartments and estimate the economic viability of silvicultural works. The average business result in the forest holding was 10 073 euros per year. The average business result per hectare was 45 euros. The turnover of the forest holdings remained positive in the whole period expect the last year, because there were no fellings according to the forest management plan. The profitability of the forest holdings can be improved by making part of the silvicultural work on your own instead of buying the service. The Profitability calculation programme was suitable for examining the profitability at the forest holding level. Because the software requires a forest management plan, the profitability can be estimated as reliably as possible. The uncertainty in the calculations is based on long term esti-mates in cash flows. Motti-software is suitable for comparing silvicultural works and fellings at a compartment level. Motti-software does not have an option to simulate natural or human damage to the development of a forest stand

Disruption of paired-associate learning in rat offspring perinatally exposed to dioxins

The prevalence of cognitive abnormalities in children has partly been ascribed to environmental chemical exposure. Appropriate animal models and tools for evaluating higher brain function are required to examine this problem. A recently developed behavioral test in which rats learn six unique flavor-location pairs in a test arena was used to evaluate paired-associate learning, a hallmark of the higher cognitive function that is essential to language learning in humans. Pregnant Long-Evans rats were dosed by gavage with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 2,3,7,8-tetrabromodibenzo-p-dioxin (TBDD) at a dose of 0, 200, or 800 ng/kg (referred as Control, TCDD-200, TCDD-800, TBDD-200, or TBDD-800, hereafter) on gestational day 15, and the offspring was tested during adulthood. Paired-associate learning was found to be impaired in the TCDD-200 and TBDD-200 groups, but not in either group exposed to 800 ng/kg, the observations of which were ensured by non-cued trials. As for the emotional aspect, during habituation, the TCDD-200 and TBDD-200 groups showed significantly longer latencies to enter the test arena from a start box than the Control, TCDD-800, and TBDD-800 groups, suggesting that the TCDD-200 and TBDD-200 groups manifested anxiety-like behavior. Thus, both the chlorinated dioxin and its brominated congener affected higher brain function to a similar extent in a nearly identical manner. Use of the behavioral test that can evaluate paired-associate learning in rats demonstrated that in utero and lactational exposure to not only TCDD but also TBDD perturbed higher brain function in rat offspring in a nonmonotonic manner

Effects of loading frequency on the functional adaptation of trabeculae predicted by bone remodeling simulation.

The process of bone remodeling is regulated by metabolic activities of many bone cells. While osteoclasts and osteoblasts are responsible for bone resorption and formation, respectively, activities of these cells are believed to be controlled by a mechanosensory system of osteocytes embedded in the extracellular bone matrix. Several experimental and theoretical studies have suggested that the strain-derived interstitial fluid flow in lacuno-canalicular porosity serves as the prime mover for bone remodeling. Previously, we constructed a mathematical model for trabecular bone remodeling that interconnects the microscopic cellular activities with the macroscopic morphological changes in trabeculae through the mechanical hierarchy. This model assumes that fluid-induced shear stress acting on osteocyte processes is a driving force for bone remodeling. The validity of this model has been demonstrated with a remodeling simulation using a two-dimensional trabecular model. In this study, to investigate the effects of loading frequency, which is thought to be a significant mechanical factor in bone remodeling, we simulated morphological changes of a three-dimensional single trabecula under cyclic uniaxial loading with various frequencies. The results of the simulation show the trabecula reoriented to the loading direction with the progress of bone remodeling. Furthermore, as the imposed loading frequency increased, the diameter of the trabecula in the equilibrium state was enlarged by remodeling. These results indicate that our simulation model can successfully evaluate the relationship between loading frequency and trabecular bone remodeling

Transient response of fluid pressure in a poroelastic material under uniaxial cyclic loading

Poroelasticity is a theory that quantifies the time-dependent mechanical behavior of a fluid-saturated porous medium induced by the interaction between matrix deformation and interstitial fluid flow. Based on this theory, we present an analytical solution of interstitial fluid pressure in poroelastic materials under uniaxial cyclic loading. The solution contains transient and steady-state responses. Both responses depend on two dimensionless parameters: the dimensionless frequency Ω that stands for the ratio of the characteristic time of the fluid pressure relaxation to that of applied forces, and the dimensionless stress coefficient H governing the solid–fluid coupling behavior in poroelastic materials. When the phase shift between the applied cyclic loading and the corresponding fluid pressure evolution in steady-state is pronounced, the transient response is comparable in magnitude to the steady-state one and an increase in the rate of change of fluid pressure is observed immediately after loading. The transient response of fluid pressure may have a significant effect on the mechanical behavior of poroelastic materials in various fields

Fluid pressure response in poroelastic materials subjected to cyclic loading

When cyclic loading is applied to poroelastic materials, a transient stage of interstitial fluid pressure occurs, preceding a steady state. In each stage, the fluid pressure exhibits a characteristic mechanical behavior. In this study, an analytical solution for fluid pressure in two-dimensional poroelastic materials, which is assumed to be isotropic, under cyclic axial and bending loading is presented, based on poroelasticity. The obtained analytical solution contains transient and steady-state responses. Both of these depend on three dimensionless parameters: the dimensionless stress coefficient; the dimensionless frequency; and, the axial-bending loading ratio. We focus particularly on the transient behavior of interstitial fluid pressure with changes in the dimensionless frequency and the axial-bending loading ratio. The transient properties, such as half-value period and contribution factor, depend largely on the dimensionless frequency and have peak values when its value is about 10. This suggests that, under these conditions, the transient response can significantly affect the mechanical behavior of poroelastic materials

Wall boundary model for primitive chain network simulations

In condensed polymeric liquids confined in slit channels, the movement of chains is constrained by two factors: entanglement among the chains and the excluded volume between the chains and the wall. In this study, we propose a wall boundary (WB) model for the primitive chain network (PCN) model, which describes the dynamics of polymer chains in bulk based on coarse graining upon the characteristic molecular weight of the entanglement. The proposed WB model is based on the assumptions that (i) polymers are not stuck but simply reflected randomly by the wall, and (ii) subchains below the entanglement length scale behave like those in bulk even near the wall. Using the WB model, we simulate the dynamics of entangled polymer chains confined in slit channels. The results show that as the slit narrows, the chains are compressed in the direction normal to the wall, while they are expanded in the parallel direction. In addition, the relaxation time of the end-to-end vector increases, and the diffusivity of the center of mass decreases. The compression in the normal direction is a natural effect of confinement, while the expansion is introduced by a hooking process near the wall. The trends revealed that the relaxation time and diffusivity depend on the increase in friction due to an increased number of entanglements near the wall, which is also associated with the hooking process in the PCN model. These results are expected within the assumptions of the PCN model. Thus, the proposed WB model can successfully reproduce the effects of wall confinement on chains

Effect of tensile force on the mechanical behavior of actin filaments.

Actin filaments are the most abundant components of the cellular cytoskeleton, and play critical roles in various cellular functions such as migration, division and shape control. In these activities, mechanical tension causes structural changes in the double-helical structure of the actin filament, which is a key modulator of cytoskeletal reorganization. This study performed large-scale molecular dynamics (MD) and steered MD simulations to quantitatively analyze the effects of tensile force on the mechanical behavior of actin filaments. The results revealed that when a tensile force of 200pN was applied to a filament consisting of 14 actin subunits, the twist angle of the filament decreased by approximately 20°, corresponding to a rotation of approximately -2° per subunit, representing a critical structural change in actin filaments. Based on these structural changes, the variance in filament length and twist angle was found to decrease, leading to increases in extensional and torsional stiffness. Torsional stiffness increased significantly under the tensile condition, and the ratio of filament stiffness under tensile force to that under no external force increased significantly on longer temporal scales. The results obtained from this study contribute to the understanding of mechano-chemical interactions concerning actin dynamics, showing that increased tensile force in the filament prevents actin regulatory proteins from binding to the filament