Levittäytymispäätöksiin vaikuttavat tekijät

Tiivistelmä. Levittäytyminen on yksi ekologian ja genetiikan tärkeimmistä mekanismeista, jolla on vaikutuksia aina eliöyhteisötasolta yksittäisten alleelien liikkumiseen paikallispopulaatioiden välillä. Levittäytymisellä tarkoitetaan sitä, että eliöyksilö siirtyy uuteen paikkaan lisääntymään. Levittäytymistä tutkitaan nykyään käyttäytymisenä, koska tarkoituksellinen siirtyminen paikasta toiseen edellyttää päätöksentekoa. Levittäytymispäätöksen syntyminen näin ollen tarkoittaa, että sen taustalla on oltava erilaisia tekijöitä, jotka ovat päätöksen syntymiseen vaikuttaneet. Tässä työssä tavoitteeni on selvittää, millaisia tekijöitä levittäytymispäätöksen taustalla voi olla. Levittäytymispäätöksiin vaikuttavat niin ympäristötekijät kuin yksilön sisäiset tekijät. Ympäristötekijöiden osalta levittäytymispäätöksissä on kyse huonoista olosuhteista lähtemisestä ja parempiin olosuhteisiin pyrkimisestä. Yksilön sisäiset tekijät puolestaan määrittävät, millaiset olosuhteet ovat kyseiselle yksilölle optimaalisimmat. Ympäristötekijöiden kohdalla puhutaan niin maisemarakenteen, eliöyhteisön, lajitoverien kuin sukulaisten vaikutuksista paikallisiin ja uuden alueen olosuhteisiin. Yksilön sisäisistä tekijöistä tärkeimpiä ovat puolestaan perimä ja kehitysympäristö ja näiden pohjalta syntyvät yksilölliset ominaisuuskokoelmat eli syndroomat, jotka voivat ohjata yksilön elämää levittäytymistä laajemmillakin osa-alueilla. Levittäytymispäätösten seuraukset ovat kauaskantoisia, koska ne johtavat sekä yksilöiden että niiden perimän siirtymiseen paikallispopulaatioiden välillä. Täten ne voivat vaikuttaa alueen populaatiodynamiikkaan ja aiheuttaa näin sekä uusien paikallispopulaatioiden syntymisiä että paikallisia sukupuuttoja. Perimäaineksen siirtyminen puolestaan vaikuttaa sopeutumiseen vallitseviin olosuhteisiin ja voi siten aiheuttaa sekä paikallispopulaatioiden samankaltaistumista että eriytymistä, jopa lajiutumiseen saakka. Levittäytymispäätösten syiden tunteminen antaa työkaluja mm. suojelubiologiaan sekä elinympäristöjen pirstaloitumisen, ilmastonmuutoksen ja tulokaslajien kanssa toimimiseen

Interspliced transcription chimeras: Neglected pathological mechanism infiltrating gene accession queries?

AbstractOver half of the DNA of mammalian genomes is transcribed, and one of the emerging enigmas in the field of RNA research is intergenic splicing or transcription induced chimerism. We argue that fused low-copy-number transcripts constitute neglected pathological mechanism akin to copy number variation, due to loss of stoichiometric subunit ratios in protein complexes. An obstacle for transcriptomics meta-analysis of published microarrays is the traditional nomenclature of merged transcript neighbors under same accession codes. Tandem transcripts cover 4–20% of genomes but are only loosely overlapping in population. They were most enriched in systems medicine annotations concerning neurology, thalassemia and genital disorders in the GeneGo Inc. MetaCore-MetaDrugTM knowledgebase, evaluated with external randomizations here. Clinical transcriptomics is good news since new disease etiologies offer new remedies. We identified homeotic HOX-transfactors centered around BMI-1, the Grb2 adaptor network, the kallikrein system, and thalassemia RNA surveillance as vulnerable hotspot chimeras. As a cure, RNA interference would require verification of chimerism from symptomatic tissue contra healthy control tissue from the same patient

Social gradient in intermediary determinants of oral health at school level in Finland

Objective: An adapted framework for oral health inequalities suggests that structural determinants cause oral health inequalities through socio-economic position (SEP) and intermediary determinants. We applied this framework to examine whether there is a social gradient in the intermediary determinants at the school level, even when adjusted for school size, geographical location and teaching language. Basic research design: Cross-sectional survey. Methods: This study combined data from two independent studies focusing on Finnish upper comprehensive schools (N=970): the School Health Promotion study (SHPS) and the School Sweet Selling survey (SSSS). All schools that took part in the SSSS and whose pupils answered the SHPS were included in the analysis (n=360, response rate=37%). From the questions of the SHPS and the SSSS suitable for the theoretical framework, attitudes and access to intoxicants, school health services, school environment, home environment, the school's oral health-related actions and the pupil's own behaviour were selected as the intermediary determinants and as the factors determining the school-level SEP. The social gradient in the intermediary determinants of oral health was investigated with Pearson's and Spearman's correlation coefficients between those and the school-level SEP. In the multivariable analysis, the General Linear Model with manual backward elimination was used. Results: A social gradient was observed in the intermediary determinants 'home environment' and 'the pupils' tooth brushing frequency' and an inverse social gradient in 'attitudes and access to intoxicants' and 'school health services'. Conclusions: Social gradient between schools could increase Finnish adolescents' oral health inequalities.</div

School-level changes in factors related to oral health inequalities after national recommendation on sweet selling

Aims: In 2007, Finnish authorities gave a national recommendation that schools should not sell sweet products. This study aimed to determine the effects of the national recommendation on school-level intermediary determinants (factors related to oral health inequalities) and if the changes were different according to school-level socio-economic position (SEP). Methods: This ecological and longitudinal study combined school-level data from two independent studies from Finnish upper comprehensive schools (N = 970): the School Health Promotion study (SHPS) and the School Sweet Selling survey (SSSS). The baseline data (SHPS from 2006–2007 and SSSS from 2007) and the post-intervention data (SHPS and SSSS from 2008–2009) were combined into a longitudinal school-level data set (n = 360 and response rate = 37%). The intermediary determinants were: attitudes and access to intoxicants, school health services, school environment, home environment, schools’ health-promoting actions (including sweet product selling) and pupils’ eating habits. Three equal-sized school-level SEP group — slow, middle and high — were formed. The changes in the intermediary determinants were analysed using Wilcoxon Signed Ranks test. Differences between school SEP groups were analysed the using Kruskal–Wallis test. Longitudinal linear mixed modelling was used to determine the contribution of intermediary determinants to the changes in pupils’ eating habits. Results: The national recommendation was effective in decreasing sweet product selling at schools and the effect was equal in each school-level SEP group. Intermediary determinants contributed differently to eating habits in the three SEP groups. Conclusions: A national recommendation seems to be an effective tool in making the school environment healthier without increasing inequalities.</p

An 8-year surveillance of the diversity and persistence of Listeria monocytogenes in a chilled food processing plant analyzed by amplified fragment length polymorphism.

Reprinted with permission from Journal of Food Protection. Copyright held by the International Association for Food Protection, Des Moines, U.S.A.Contamination routes of Listeria monocytogenes were examined in a chilled food processing plant that produced ready-to-eat and ready-to-reheat meals during an 8-year period by amplified fragment length polymorphism (AFLP) analysis. A total of 319 L. monocytogenes isolates were recovered from raw materials (n=18), the environment (n=77), equipment (n=193), and products (n=31), and 18 different AFLP types were identified, five of which were repeatedly found to be persistent types. The three compartments (I to III) of the plant showed markedly different contamination statuses. Compartment I, which produced cooked meals, was heavily contaminated with three persistent AFLP types. AFLP type A1 dominated, and it comprised 93% of the isolates of the compartment. Compartment II, which produced uncooked chilled food, was contaminated with four persistent and five nonpersistent AFLP types. The equipment of compartment III, which produced cooked ready-to-reheat meals, was free of contamination. In compartments that produced cooked meals, the cleaning routines, product types, and lack of compartmentalization seemed to predispose production lines to persistent contamination. The most contaminated lines harbored L. monocytogenes in coolers, conveyors, and packing machines. Good compartmentalization limited the flow of L. monocytogenes into the postheat -treatment area and prevented the undesired movement of equipment and personnel, thus protecting the production lines from contamination. In compartment II, grated cheese was shown to cause product contamination. Therefore, special attention should be paid to continuous quality control of raw ingredients when uncooked ready-to-eat foods are produced. In compartment II, reconstruction of the production line resulted in reduced prevalence rates of L. monocytogenes and elimination of two persistent AFLP types

Acoustic Emission from Paper Fracture

We report tensile failure experiments on paper sheets. The acoustic emission energy and the waiting times between acoustic events follow power-law distributions. This remains true while the strain rate is varied by more than two orders of magnitude. The energy statistics has the exponent $\beta \sim 1.25 \pm 0.10$ and the waiting times the exponent $\tau \sim 1.0 \pm 0.1$, in particular for the energy roughly independent of the strain rate. These results do not compare well with fracture models, for (brittle) disordered media, which as such exhibit criticality. One reason may be residual stresses, neglected in most theories.Comment: 4 pages, 5 figure

Task-oriented reading efficiency: interplay of general cognitive ability, task demands, strategies and reading fluency

The associations among readers’ cognitive skills (general cognitive ability, reading skills, and attentional functioning), task demands (easy versus difficult questions), and process measures (total fixation time on relevant and irrelevant paragraphs) was investigated to explain task-oriented reading accuracy and efficiency (number of scores in a given time unit). Structural equation modeling was applied to a large dataset collected with sixth-grade students, which included samples of dysfluent readers and those with attention difficulties. The results are in line with previous findings regarding the dominant role of general cognitive ability in the accuracy of task-oriented reading. However, efficiency in task-oriented reading was mostly explained by the shorter viewing times of both paragraph types (i.e., relevant and irrelevant), which were modestly explained by general cognitive ability and reading fluency. These findings suggest that high efficiency in task orientation is obtained by relying on a selective reading strategy when reading both irrelevant and relevant paragraphs. The selective reading strategy seems to be specifically learned, and this potentially applies to most students, even those with low cognitive abilities

BMI in childhood and adolescence is associated with impaired reproductive function-a population-based cohort study from birth to age 50 years

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