Does Density-Dependent Individual Growth Simplify Dynamics in Age-Structured Populations? A General Model Applied to Perch, "Perca fluviatilis"

Availability of resources is a limiting factor for many populations. Diminished resource availability due to intraspecific competition is expected to decrease the annual growth increments of individuals. We study an age- structured population model for individuals with indeterminate growth and annual reproduction; parameters of the model are chosen to characterize a population with life history similar to the Eurasian perch. Different variants of this model are analyzed, all of which have a potential for exhibiting non-equilibrium population fluctuations. We demonstrate that by incorporating density-dependent individual growth into these models changes the dynamics of these populations by damping or even eradicating fluctuations in abundance and biomass. This finding offers an explanation for the observed stable dynamics of unperturbed perch populations. Further, density-dependent individual growth may also be a significant factor for contributing to the conspicuous empirical rarity of non-equilibrium population dynamics in general

Ecology and Adaptation of Stunted Growth in Fish [Updated August 2000]

Dwarf individuals are observed in many species of freshwater fish. This paper studies the potential causes of such stunted growth. We present a model which describes the effect of growth conditions on the age- and size- structure of fish populations. The model parameters are chosen to characterize a Eurasian perch population. Two possible causes of stunting are identified: resource limitation and size- or age-dependent survival probabilities. While the former mechanism often arises from intraspecific density dependence, the latter is of particular relevance in the context of interspecific interactions and fishing. After evaluating the immediate ecological consequences of these factors, we examine the potential for life-history adaptations in stunted fish populations. Interactions between the ecological and adaptive mechanisms of stunting are shown to be intricate: not only does the age at maturity of individuals affect their growth trajectories, but, in addition, alterations in growth conditions can result in different adaptively stable ages at maturity. We show that such adaptive responses can either alleviate or amplify stunting caused by ecological factors. Life-history adaptation may also lead to the persistence of stunting when ecological factors alone would allow for normal growth. An appreciation of the interplay between ecological and adaptive factors therefore is critical for understanding the causes and mechanisms of stunted growth

Community-driven dispersal in an individual-based predator-prey model

We present a spatial, individual-based predator-prey model in which dispersal is dependent on the local community. We determine species suitability to the biotic conditions of their local environment through a time and space varying fitness measure. Dispersal of individuals to nearby communities occurs whenever their fitness falls below a predefined tolerance threshold. The spatiotemporal dynamics of the model is described in terms of this threshold. We compare this dynamics with the one obtained through density-independent dispersal and find marked differences. In the community-driven scenario, the spatial correlations in the population density do not vary in a linear fashion as we increase the tolerance threshold. Instead we find the system to cross different dynamical regimes as the threshold is raised. Spatial patterns evolve from disordered, to scale-free complex patterns, to finally becoming well-organized domains. This model therefore predicts that natural populations, the dispersal strategies of which are likely to be influenced by their local environment, might be subject to complex spatiotemporal dynamics.Comment: 43 pages, 7 figures, vocabulary modifications, discussion expanded, references added, Ecological Complexity accepte

Ryhmäkoon merkitys lapsen sosioemotionaalisen kompetenssin kehitykselle varhaiskasvatuksessa

Tiivistelmä. Tutkielmamme tavoitteena oli muodostaa syvempi ja laajempi ymmärrys lapsen sosioemotionaalisen kompetenssin kehitykseen liittyvistä tekijöistä varhaiskasvatusryhmässä. Huomiomme kiinnittyi erityisesti ryhmäkokoon mahdollisena selittävänä tekijänä, sillä ryhmäkoko on yhteydessä lasten kehitykseen muun muassa sosiaalisten taitojen sekä vertaissuhteiden osalta. Tarkoituksenamme oli etsiä aihettamme eri näkökulmista lähestyviä tutkimuksia ja siten koota vastauksia tutkimuskysymykseemme siitä, millainen merkitys ryhmäkoolla on lapsen sosioemotionaalisen kompetenssin kehitykselle varhaiskasvatuksessa. Toteutimme kvalitatiivisen tutkielmamme integroivana kirjallisuuskatsauksena, jonka ensimmäinen vaihe oli viitekehyksen kokoaminen. Sen jälkeen keräsimme aineistoomme tutkimuksia, jotka liittyivät tutkimaamme aiheeseen sosioemotionaalisen kompetenssin eri osa-alueiden kautta. Lopulliseen aineistoon valitsimme kuusi tutkimusta aikaväliltä 2012–2018, joiden tulokset analysoimme referoimalla ne ensin lyhyesti, minkä jälkeen reflektoimme niitä viitekehyksemme avulla. Käytimme analyysimenetelmänä teemoittelua. Tutkimusten tuloksista nostimme kolme teemaa: 1) lasten välinen vuorovaikutus ja vertaissuhteet, 2) opettajien mahdollisuudet tukea lasten vertaissuhteita ryhmämuotoisessa toiminnassa sekä 3) opettajien kokemus lapsiryhmän koosta. Näiden teemojen kautta jaoimme tutkimukset niiden tuloksissa ilmenneiden aiheiden mukaan. Tulokseksi saimme, että ryhmä tai ryhmäkoko on jonkin verran yhteydessä lasten sosioemotionaalisen kompetenssin kehitykseen. Muita siihen liittyviä tekijöitä olivat opettajien näkemys sosiaalisten taitojen tärkeydestä, lapsiryhmän haasteiden ratkaiseminen pedagogisesti koko ryhmää hyödyttävällä tavalla, opettajien huoli lasten yksilöllisestä huomioimisesta suurissa ryhmissä, inklusiivisen kasvatuksen merkitys lasten sosiaaliselle kompetenssille ja vertaissuhteille, vuorovaikutuksen laadun yhteys lasten hyvinvointiin ja sosioemotionaalisen kompetenssin kehitykselle sekä inhibitio- ja tunnesäätelykyvyn rooli lasten vertaissuhteissa.The significance of group size for a child’s development of socioemotional competence in early childhood education. Abstract. The aim of our thesis was to create a deeper and more comprehensive understanding of the factors that are connected to the development of children’s socioemotional competence in an early childhood education group. We focused especially on the group size as an explaining factor since it’s connected to the children’s development of social skills and peer relationships among other things. Our purpose was to find researches that approached our subject from different aspects. This way we were able to combine answers to the research question of our thesis. Our research question was about the significance of group size for a child’s development of socioemotional competence in early childhood education. We chose to use an integrative literature review as the method of our qualitative thesis. First, we gathered the conceptual framework and then we collected researches to our material. The researches had to focus on the subject of our thesis through different elements of the socioemotional competence. For our final material we selected six researches from 2012 to 2018. Then we analyzed the results of those researches and reflected them with our conceptual framework. We used thematical analysis as our analytical method. Our themes were: 1) interaction and peer relationships between children, 2) a teacher’s opportunities to support the peer relationships of children in group-based activities and 3) teachers’ experience about the size of a group of children. This way we were able to distribute the researches according to their topics. As our results we found out that the group or the group size is connected to the development of children’s socioemotional competence to some extent. The other associated factors were the teachers’ opinions about the importance of social skills, solving the problems in children’s group in a pedagogical way that benefits every child in the group and the teachers’ concern of paying attention to each child individually in large kindergarten groups. Other factors were the significance of inclusive education practice for children’s social competence and peer relationships, how the quality of interaction is connected to the wellbeing of children and the development of socioemotional competence and lastly the role of inhibitory control and self-regulation skills in children’s peer relationships

Corpus Vasorum Antiquorum, Finland

The Finnish collections of Graeco-Roman pottery result mostly from haphazard acquisitions since the beginning of the nineteenth century, and are in only a very few cases the fruits of systematic collection. As, for almost two centuries, the tradition of classical archaeology in Finland has depended on the interest of private individuals, it is no wonder that only two objects in the present CVA volume are previously published.The CVA Finland, fascicule 1 thus fills a major scholarly and museological gap. The study and publication of these vases aims to dispel their anonymity, conveying them to anyone interested in Greek and Roman pottery.The Finnish collections of Graeco-Roman pottery result mostly from haphazard acquisitions since the beginning of the nineteenth century, and are in only a very few cases the fruits of systematic collection. As, for almost two centuries, the tradition of classical archaeology in Finland has depended on the interest of private individuals, it is no wonder that only two objects in the present CVA volume are previously published.The CVA Finland, fascicule 1 thus fills a major scholarly and museological gap. The study and publication of these vases aims to dispel their anonymity, conveying them to anyone interested in Greek and Roman pottery.The Finnish collections of Graeco-Roman pottery result mostly from haphazard acquisitions since the beginning of the nineteenth century, and are in only a very few cases the fruits of systematic collection. As, for almost two centuries, the tradition of classical archaeology in Finland has depended on the interest of private individuals, it is no wonder that only two objects in the present CVA volume are previously published.The CVA Finland, fascicule 1 thus fills a major scholarly and museological gap. The study and publication of these vases aims to dispel their anonymity, conveying them to anyone interested in Greek and Roman pottery

"ASIA ON AINA OLLUT TODELLINEN JA HE OVAT NÄHNEET SEN" : Nuorten kokemuksia opiskeluterveydenhuollon palveluista

Tutkimuksen tarkoituksena oli kartoittaa, miten Kokkolan toisen asteen opiskelijat kokevat saavansa tukea ja apua ongelmiinsa opiskelijaterveydenhuollon kautta. Tavoitteena oli tuottaa tietoa Vartu-projektille nuorten kokemuksista sekä kohtaamistaan haasteista opiskeluterveydenhuollon palveluiden käyttäjinä. Tutkimuksen toimeksiantajana toimi Vartu-projekti, jonka tarkoituksena on edistää 13−29-vuotiaiden nuorten mahdollisuuksia löytää apua ja tukea erityistarpeisiinsa matalalla kynnyksellä Keski-Pohjanmaan alueella. Tutkimusmenetelmänä käytettiin laadullista lähestymistapaa. Aineistonkeruumenetelmänä käytettiin avointa kyselyä. Tutkimuksen kohderyhmänä toimi yksi Kokkolan toisen asteen opiskelijaryhmä, ja kysely toteutettiin luokassa yhden oppitunnin aikana. Aineiston analysoinnissa käytettiin induktiivista sisällönanalyysiä. Nuoret kertoivat hakeneensa opiskeluterveydenhuollon kautta apua somaattisiin sairauksiin, psyykkisiin haasteisiin ja terveysneuvontaan. Suurin osa nuorista koki pääsyn terveydenhoitajan vastaanotolle helpoksi tai melko helpoksi. Osalla nuorista oli vaihtelevia kokemuksia vastaanotolle pääsystä. Nuoret kokivat, että terveydenhoitajan vastaanotolle pääsyyn vaikuttivat kiireellisyyden arviointi, opiskeluterveydenhuollon resurssit sekä monipuolinen ajanvarausjärjestelmä. Nuorten mukaan opiskeluterveydenhuollon hyviä puolia olivat opiskelijalähtöisyys, ajanvarauskäytännöt, hoitosuhteen laatu, terveydenhoitajan osaaminen sekä terveydenhoitajan persoonallisuus. Opiskeluterveydenhuollon kehitettäviksi puoliksi mainittiin päivystysaikojen vähäisyys ja se, ettei terveydenhoitajan vastaanotolle aina pääse.The purpose of this study was to find out how students in vocational upper secondary education in Kokkola experience getting support and help with their problems through student health care. The aim was to provide information for the Vartu-project about adolescent experiences and the challenges they have encountered as student health service customers. This study was assigned by Vartu-project. Vartu-project’s goal is to promote the possibilities of 13-29-years-old adolescents’ easy access to find support and help with their specific needs in Central Ostrobothnia. Qualitative research approach was used in this study. The information was gathered by an open questionnaire from a student group in vocational upper secondary education in Kokkola during one lesson. The material was analyzed using inductive content analysis. The study revealed that the students had seeked for help through student health services for somatic illnesses, psychic challenges and health counseling. Most of the students experienced that it was easy or quite easy to access the student health services. Some of the students had variable experiences about the accessibility. The students experienced that urgency evaluation, student health care resources and a versatile appointment system affected the accessibility of student health services. According to the students the positive sides of student health services was student orientation, appointment policies, the quality of the care relationship, and a professional student health nurse with a good personality. Limited on-call time was mentioned as a side of student health services that needs improvement