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Photoperiodic reproductive diapause is an essential part of female life cycle in several insect species living on high latitudes, where overwintering in reproductive stage involves high risks for survival and progeny production. The sensitive period (SP), during which photoperiodic cues can trigger the switch from direct development to diapause, can last from a few hours or days after emergence to the entire life span of females. Moreover, in some species, sexually mature females can enter post-reproductive diapause as a response to decreasing day length and/or temperature. We studied the duration of SP for diapause induction and the females' ability to enter post-reproductive diapause at short day lengths in

Interspecific gene flow (introgression) is an important source of new genetic variation, but selection against it can reinforce reproductive barriers between interbreeding species. We used an experimental approach to trace the role of chromosomal inversions and incompatibility genes in preventing introgression between two partly sympatricDrosophila virilisgroup species,D. flavomontanaandD. montana. We backcrossed F1hybrid females from a cross betweenD. flavomontanafemale andD. montanamale with the males of the parental species for two generations and sequenced pools of parental strains and their reciprocal 2ndgeneration backcross (BC2mon and BC2fla) females. Contrasting the observed amount of introgression (mean hybrid index, HI) in BC2female pools along the genome to simulations under different scenarios allowed us to identify chromosomal regions of restricted and increased introgression. We found no deviation from the HI expected under a neutral null model for any chromosome for the BC2mon pool, suggesting no evidence for genetic incompatibilities in backcrosses towardsD. montana. In contrast, the BC2fla pool showed high variation in the observed HI between different chromosomes, and massive reduction of introgression on the X chromosome (large X-effect). This observation is compatible with reduced recombination combined with at least one dominant incompatibility locus residing within the X inversion(s). Overall, our study suggests that genetic incompatibilities arising within chromosomal inversions can play an important role in speciation.

BackgroundTracing the association between insect cold tolerance and latitudinally and locally varying environmental conditions, as well as key morphological traits and molecular mechanisms, is essential for understanding the processes involved in adaptation. We explored these issues in two closely-related species, Drosophila montana and Drosophila flavomontana, originating from diverse climatic locations across several latitudes on the coastal and mountainous regions of North America. We also investigated the association between sequence variation in one of the key circadian clock genes, vrille, and cold tolerance in both species. Finally, we studied the impact of vrille on fly cold tolerance and cold acclimation ability by silencing it with RNA interference in D. montana.ResultsWe performed a principal component analysis (PCA) on variables representing bioclimatic conditions on the study sites and used latitude as a proxy of photoperiod. PC1 separated the mountainous continental sites from the coastal ones based on temperature variability and precipitation, while PC2 arranged the sites based on summer and annual mean temperatures. Cold tolerance tests showed D. montana to be more cold-tolerant than D. flavomontana and chill coma resistance (CTmin) of this species showed an association with PC2. Chill coma recovery time (CCRT) of both species improved towards northern latitudes, and in D. flavomontana this trait was also associated with PC1. D. flavomontana flies were darkest in the coast and in the northern mountainous populations, but coloration showed no linkage with cold tolerance. Body size decreased towards cold environments in both species, but only within D. montana populations largest flies showed fastest recovery from cold. Finally, both the sequence analysis and RNAi study on vrille suggested this gene to play an essential role in D. montana cold resistance and acclimation, but not in recovery time.ConclusionsOur study demonstrates the complexity of insect cold tolerance and emphasizes the need to trace its association with multiple environmental variables and morphological traits to identify potential agents of natural selection. It also shows that a circadian clock gene vrille is essential both for short- and long-term cold acclimation, potentially elucidating the connection between circadian clock system and cold tolerance.

Insect species with a wide distribution offer a great opportunity to trace latitudinal variation in the photoperiodic regulation of traits important in reproduction and stress tolerances. We measured this variation in the photoperiodic time-measuring system underlying reproductive diapause in Drosophila montana, using a Nanda-Hamner (NH) protocol. None of the study strains showed diel rhythmicity in female diapause proportions under a constant day length (12 h) and varying night lengths in photoperiods ranging from 16 to 84 h at 16°C. In the northernmost strains (above 55°N), nearly all females entered diapause under all photoperiods and about half of them even in continuous darkness, while the females of the southern strains showed high diapause proportions only in the circadian 24 h photoperiod. Significant correlation between the strains’ mean diapause proportions in ≥ 24 h photoperiods and critical day length (CDL; half of the females enter diapause) suggests at least partial causal connection between the traits. Interestingly, females of the northern strains entered diapause even in ≤ 24 h photoperiods, where the night length was shorter than their critical night length (24 h - CDL), but where the females experienced a higher number of Light:Dark cycles than in 24 h photoperiods. NH experiments, performed on the control and selection lines in our previous selection experiment, and completed here, gave similar results and confirmed that selection for shorter, southern-type CDL decreases female diapausing rate in non-circadian photoperiods. Overall, our study shows that D. montana females measure night length quantitatively, that the photoperiodic counter may play a prominent but slightly different role in extra short and extra long photoperiods and that northern strains show high stability against perturbations in the photoperiod length and in the presence of LD cycles. These features are best explained by the quantitative versions of the damped external coincidence model.

Tiivistelmä. Tässä diplomityössä tarkastellaan teräsbetonisten siltakansien vedeneristeen kuplimisongelmaa. Yleisen suomalaisen käsityksen mukaan kupliminen johtuu betonirakenteen suurista kosteuspitoisuuksista, betonin huokoisuudesta ja työvirheistä. Kuitenkaan kuplimisongelma ei ole ratkennut ja kupliminen aiheuttaa edelleen yhteiskunnalle liikenteellisiä haittoja ja ylimääräisiä korjauskustannuksia. Diplomityön tavoitteena oli perehtyä siltakansien vedeneristeen kuplimisongelmaan sekä kotimaisten että kansainvälisten tutkimusten kautta, ja pyrkiä löytämään uusia näkökulmia ja havaintoja kuplimisongelman ymmärtämiseksi. Työn tavoitteena oli myös kartoittaa mahdollisia jatkotutkimustarpeita uusien näkökulmien ja havaintojen tueksi. Työvirheet olivat edelleenkin suurin kuplimisen selittävä tekijä valtaosassa tutkimuksista. Uusien tutkimusten mukaan myös kuumuudella oli suuri myötävaikutus kuplien muodostumiseen siltakannelle. Kansainvälisten tutkimusten mukaan vesihöyrynpaineen lisäksi kuumuus aiheuttaa siltakannella kemiallisia reaktioita, jotka ovat nimetty kylmä- ja kuumaprosesseiksi. Myös osmoosin vaikutus kuplimiseen on tiedostettu kosteilla betonialustoilla. Tutkimuksen perusteella kuplimista voitaisiin vähentää rajoittamalla muodostuvan kaasun painetta kermin alle. Eristysalustan kuivattaminen kosteusvaatimuksiin on oleellinen asia tartuntalujuuksien kannalta. Ehyt tiivistyskäsittely tai laadukas suojabetonikerros estävät kuplan muodostumisen pintarakenteeseen. Työvirheiden välttäminen ja tarkat laadunmittaukset ovat loppujen lopuksi avain onnistumiseen.Problem with blistering of waterproofing of reinforced concrete bridge decks. Abstract. This thesis examines the blistering problem of the waterproofing of reinforced concrete bridge decks. The common consensus within Finland, is that blistering is caused due to the high moisture content of the concrete structure, the porosity of the concrete and work defects. Despite the identification of these issues, blistering has not been solved and blistering continues to cause roadway inconveniences and incurs additional repair costs for the taxpayer. The aim of this thesis was to become acquainted with the blistering problem that can occur during the bridge deck waterproofing process. Information was gathered using both domestic and international studies so as to discover new perspectives and to better understand the blistering problem and its causes. The aim of this work is also to map the possible needs for further research of this topic. This research identified work defects as being the most prominent explanatory factor for blistering in the majority of studies. According to more recent studies, temperature contributed greatly to the formation of blisters on bridge decks. According to international studies, in addition to water vapor pressure, variances in temperature cause chemical reactions within the bridge deck, termed cold and hot processes. These chemical processes should be studied in greater detail in Finland, so as to gain a better understanding of this problem and to allow for the development of new methods and quality guidelines pertaining to materials and/or practices to limit the possibilities of chemical reactions. According to this study, blistering could be reduced by limiting the pressure of the gas formed below the waterproofing. Ensuring that the insulation substrate is dry and meets the moisture requirements is essential for adhesion strength during the waterproofing process. Proper sealing treatment or a protective concrete layer aides in the prevention of blister formation in the surface structure. Avoiding work defects and ensuring accurate measurements are crucial to the success of, as well.

Tiivistelmä. Pro gradu -tutkielma tutkii matalaa hierarkiaa ja johtajien johtamistyylejä. Aikaisemmat tutkimukset osoittavat, että nykypäivänä korkea hierarkia organisaatioissa ei enää toimi. Sen sijaan tulisi hyödyntää matalaa hierarkiaa. Aikaisempien tutkimusten tuloksista ei kuitenkaan ilmene, millä tavalla matala hierarkia saadaan toteutettua. Tämän tutkimuksen tavoitteena on selvittää, millä tavalla johtajat käyttäytyvät matalan hierarkian organisaatiossa ja minkälaisia konkreettisia muutoksia johtajan johtamistyylissä matalan hierarkian toteutuminen vaatii. Tarkoituksena on siis saada vastaus siihen, että miten matala hierarkia konkreettisesti saavutetaan johtamistyylien avulla ja käytösmalleja muuttamalla. Kyseessä on kvalitatiivinen tutkimus. Tutkimukseen osallistui kolme organisaation keski- tai ylimmän johdon johtajaa. Aineisto kerättiin teemahaastatteluilla, jotka litteroitiin. Teemahaastattelujen teemat olivat työtyytyväisyys, motivaatio, työn laatu ja tehokkuus, menestys ja tulokset, hyvinvointi, sekä suorituskyky ja sitoutuminen. Aineiston käsittelemisessä hyödynnettiin sisällönanalyysiä. Tärkeimmät tutkimustulokset koskevat organisaatiossa nopeaa viestintää, läpinäkyvyyttä ja johtajan aitoa kiinnostusta ja luottamusta alaisia kohtaan. Lisäksi vapauden antaminen alaisille, johtaminen kohti itseohjautuvuutta sekä johtajan yhteisöllisyyden parantaminen helposti lähestyttävyydellä ovat ominaista matalan hierarkian johtajille. Matalan hierarkian johtajat nähdään pomon sijasta osana tiimiä ja johtajilla on hyvät kuuntelemisen taidot. Tuloksia voi hyödyntää jatkossa matalan hierarkian organisaatioissa, joissa halutaan saavuttaa mahdollisimman hyvä organisaatiokulttuuri. Tutkimuksen tuloksia voi toisaalta hyödyntää myös korkeamman hierarkian omaavissa organisaatioissa, jos tarkoitus on madalluttaa hierarkiaa. Organisaatioiden sisällä tutkimustuloksia voi hyödyntää ylin johto, keskijohto, esimiestaso tai työntekijät koulutus- tai kehitystarkoituksiin. Organisaatioiden lisäksi myös koulutuslaitokset voivat hyödyntää tutkimustuloksia materiaalina.

Background The PIM family kinases promote cancer cell survival and motility as well as metastatic growth in various types of cancer. We have previously identified several PIM substrates, which support cancer cell migration and invasiveness. However, none of them are known to regulate cellular movements by directly interacting with the actin cytoskeleton. Here we have studied the phosphorylation-dependent effects of PIM1 on actin capping proteins, which bind as heterodimers to the fast-growing actin filament ends and stabilize them. Methods Based on a phosphoproteomics screen for novel PIM substrates, we have used kinase assays and fluorescence-based imaging techniques to validate actin capping proteins as PIM1 substrates and interaction partners. We have analysed the functional consequences of capping protein phosphorylation on cell migration and adhesion by using wound healing and real-time impedance-based assays. We have also investigated phosphorylation-dependent effects on actin polymerization by analysing the protective role of capping protein phosphomutants in actin disassembly assays. Results We have identified capping proteins CAPZA1 and CAPZB2 as PIM1 substrates, and shown that phosphorylation of either of them leads to increased adhesion and migration of human prostate cancer cells. Phosphorylation also reduces the ability of the capping proteins to protect polymerized actin from disassembly. Conclusions Our data suggest that PIM kinases are able to induce changes in actin dynamics to support cell adhesion and movement. Thus, we have identified a novel mechanism through which PIM kinases enhance motility and metastatic behaviour of cancer cells. Graphical abstract

Supplemental material, sj-pdf-1-jbr-10.1177_07487304221108968 for Plasticity in Photoperiodism: Drosophila montana Females Have a Life-Long Ability to Switch From Reproduction to Diapause by Pekka Lankinen, Chedly Kastally and Anneli Hoikkala in Journal of Biological Rhythms

Photoperiodic reproductive diapause is an essential part of female life cycle in several insect species living on high latitudes, where overwintering in reproductive stage involves high risks for survival and progeny production. The sensitive period (SP), during which photoperiodic cues can trigger the switch from direct development to diapause, can last from a few hours or days after emergence to the entire life span of females. Moreover, in some species, sexually mature females can enter post-reproductive diapause as a response to decreasing day length and/or temperature. We studied the duration of SP for diapause induction and the females’ ability to enter post-reproductive diapause at short day lengths in Drosophila montana strains from different latitudes in Europe, North America, and Japan. Our study shows that the females of this species have a life-long SP and that they retain an ability to switch between reproduction and diapause as a response to back-and-forth changes in day length for at least 3 months. D. montana strains from different latitudes showed high variation in females’ ability to enter post-reproductive diapause; females of the southern strains generally requiring longer time and/or lower temperature to enter this stage than those of the northern strains. Moreover, the proportion of females that switched to post-reproductive diapause in 3 weeks in short day conditions at 16 °C showed positive correlation with the critical day length (CDL) for diapause induction and the latitudinal and continental origin of the strains. Life-long SP increases females’ flexibility to respond to short-term changes in environmental conditions and enables reproducing females to switch to post-reproductive diapause when the days get shorter and colder toward the autumn. This ability can play a major role in species phenology and should be taken into account in theoretical and empirical studies on insect adaptation to seasonal variation. peerReviewed

Tutkimuksessa tarkasteltiin seksuaalirikoksen tekijöitä, tekotilanteita sekä arvioitiin tulosten ja ennaltaehkäiseviä toimenpiteitä käsittelevän kirjallisuuskatsauksen avulla seksuaalirikosten ennaltaehkäisyn mahdollisuuksia Suomessa. Tutkimuksessa käytettiin rekisteri- ja kyselyaineistoja sekä seksuaalirikosten tekijöiltä ja heidän kanssaan työskenteleviltä asiantuntijoilta kerättyä haastatteluaineistoa. Tutkimustulosten mukaan erityisesti nuori ikä, varhaiset riskitekijät sekä sosiaalinen huonoosaisuus ovat yhteydessä seksuaalirikoksiin. Myös ulkomailla syntyneillä oli korkeampi riski syyllistyä seksuaalirikokseen, mikä ei selittynyt huono-osaisuudella. Tulosten mukaan tekijät valitsevat usein uhreikseen päihtyneitä henkilöitä. Painostaminen ja lahjominen kohdistuvat enemmän nähden heikommassa asemassa oleviin. Lapseen kohdistuva seksuaalirikos on monen tekijän summa, ja seksuaalirikokseen johtava prosessi alkaa tyypillisesti psykologisesta lähentymisestä tekijän ja uhrin välillä. Tekijöille oli tyypillistä kokea uhri aktiiviseksi. Nuorten kokema seksuaalinen väkivalta tapahtuu yleensä nuorten keskuudessa tuttujen välillä. Tulosten pohjalta laadittiin toimenpidesuositukset seksuaalirikosten ennaltaehkäisemiseksi.

Parasitism by bacteriophages has led to the evolution of a variety of defense mechanisms in their host bacteria. However, it is unclear what factors lead to specific defenses being deployed upon phage infection. To explore this question, we co-evolved the bacterial fish pathogen Flavobacterium columnare and its virulent phage V156 in presence and absence of a eukaryotic host signal (mucin) for sixteen weeks. The presence of mucin leads to a dramatic increase in CRISPR spacer acquisition, especially in low nutrient conditions where over 60% of colonies obtain at least one new spacer. Additionally, we show that the presence of a competitor bacterium further increases CRISPR spacer acquisition in F. columnare. These results suggest that ecological factors are important in determining defense strategies against phages, and that the phage-bacterium interactions on mucosal surfaces may select for the diversification of bacterial immune systems.

Parasitism by bacteriophages has led to the evolution of a variety of defense mechanisms in their host bacteria. However, it is unclear what factors lead to specific defenses being deployed upon phage infection. To explore this question, we exposed the bacterial fish pathogenFlavobacterium columnareto its virulent phage V156 in the presence of a eukaryotic host signal (mucin). All tested conditions led to some level of innate immunity, but the presence of mucin led to a dramatic increase in CRISPR spacer acquisition, especially in low nutrient conditions where over 60% of colonies had obtained at least one new spacer. Additionally, we show that the presence of a competitor bacterium further increases CRISPR spacer acquisition inF. columnare. These results suggest that ecological factors are important in determining defense strategies against phages, and that the concentration of phages on metazoan surfaces may select for the diversification of bacterial immune systems.

C. Wright Millsin sosiologinen elämä / Juha Suoranta. Tampere : Vastapaino, 2017. Tallinna : Tallinna Raamatutrükikoja Oü.

Increasing problems with antibiotic resistance have directed interest toward phage therapy in the aquaculture industry. However, phage resistance evolving in target bacteria is considered a challenge. To investigate how phage resistance influences the fish pathogen Flavobacterium columnare, two wild-type bacterial isolates, FCO-F2 and FCO-F9, were exposed to phages (FCO-F2 to FCOV-F2, FCOV-F5, and FCOV-F25, and FCO-F9 to FCL-2, FCOV-F13, and FCOV-F45), and resulting phenotypic and genetic changes in bacteria were analyzed. Bacterial viability first decreased in the exposure cultures but started to increase after 1 to 2 days, along with a change in colony morphology from original rhizoid to rough, leading to 98% prevalence of the rough morphotype. Twenty-four isolates (including four isolates from no-phage treatments) were further characterized for phage resistance, antibiotic susceptibility, motility, adhesion, and biofilm formation, protease activity, whole-genome sequencing, and virulence in rainbow trout fry. The rough isolates arising in phage exposure were phage resistant with low virulence, whereas rhizoid isolates maintained phage susceptibility and high virulence. Gliding motility and protease activity were also related to the phage susceptibility. Observed mutations in phage-resistant isolates were mostly located in genes encoding the type IX secretion system, a component of the Bacteroidetes gliding motility machinery. However, not all phage-resistant isolates had mutations, indicating that phage resistance in F. columnare is a multifactorial process, including both genetic mutations and changes in gene expression. Phage resistance may not, however, be a challenge for development of phage therapy against F. columnare infections since phage resistance is associated with decreases in bacterial virulence. IMPORTANCE Phage resistance of infectious bacteria is a common phenomenon posing challenges for the development of phage therapy. Along with a growing world population and the need for increased food production, constantly intensifying animal farming has to face increasing problems of infectious diseases. Columnaris disease, caused by Flavobacterium columnare, is a worldwide threat for salmonid fry and juvenile farming. Without antibiotic treatments, infections can lead to 100% mortality in a fish stock. Phage therapy of columnaris disease would reduce the development of antibiotic-resistant bacteria and antibiotic loads by the aquaculture industry, but phage-resistant bacterial isolates may become a risk. However, phenotypic and genetic characterization of phage-resistant F. columnare isolates in this study revealed that they are less virulent than phage-susceptible isolates and thus not a challenge for phage therapy against columnaris disease. This is valuable information for the fish farming industry globally when considering phage-based prevention and curing methods for F. columnare infections.

Insect species with a wide distribution offer a great opportunity to trace latitudinal variation in the photoperiodic regulation of traits important in reproduction and stress tolerances. We measured this variation in the photoperiodic time-measuring system underlying reproductive diapause in Drosophila montana, using a Nanda-Hamner (NH) protocol. None of the study strains showed diel rhythmicity in female diapause proportions under a constant day length (12 h) and varying night lengths in photoperiods ranging from 16 to 84 h at 16°C. In the northernmost strains (above 55°N), nearly all females entered diapause under all photoperiods and about half of them even in continuous darkness, while the females of the southern strains showed high diapause proportions only in the circadian 24 h photoperiod. Significant correlation between the strains’ mean diapause proportions in ≥ 24 h photoperiods and critical day length (CDL; half of the females enter diapause) suggests at least partial causal connection between the traits. Interestingly, females of the northern strains entered diapause even in ≤ 24 h photoperiods, where the night length was shorter than their critical night length (24 h - CDL), but where the females experienced a higher number of Light:Dark cycles than in 24 h photoperiods. NH experiments, performed on the control and selection lines in our previous selection experiment, and completed here, gave similar results and confirmed that selection for shorter, southern-type CDL decreases female diapausing rate in non-circadian photoperiods. Overall, our study shows that D. montana females measure night length quantitatively, that the photoperiodic counter may play a prominent but slightly different role in extra short and extra long photoperiods and that northern strains show high stability against perturbations in the photoperiod length and in the presence of LD cycles. These features are best explained by the quantitative versions of the damped external coincidence model.

Supplemental material, sj-pdf-1-jbr-10.1177_0748730421997265 for Nanda-Hamner Curves Show Huge Latitudinal Variation but No Circadian Components in Drosophila Montana Photoperiodism by Pekka Lankinen, Chedly Kastally and Anneli Hoikkala in Journal of Biological Rhythms

Insect species with a wide distribution offer a great opportunity to trace latitudinal variation in the photoperiodic regulation of traits important in reproduction and stress tolerances. We measured this variation in the photoperiodic time-measuring system underlying reproductive diapause in Drosophila montana, using a Nanda-Hamner (NH) protocol. None of the study strains showed diel rhythmicity in female diapause proportions under a constant day length (12 h) and varying night lengths in photoperiods ranging from 16 to 84 h at 16°C. In the northernmost strains (above 55°N), nearly all females entered diapause under all photoperiods and about half of them even in continuous darkness, while the females of the southern strains showed high diapause proportions only in the circadian 24 h photoperiod. Significant correlation between the strains’ mean diapause proportions in ≥ 24 h photoperiods and critical day length (CDL; half of the females enter diapause) suggests at least partial causal connection between the traits. Interestingly, females of the northern strains entered diapause even in ≤ 24 h photoperiods, where the night length was shorter than their critical night length (24 h - CDL), but where the females experienced a higher number of Light:Dark cycles than in 24 h photoperiods. NH experiments, performed on the control and selection lines in our previous selection experiment, and completed here, gave similar results and confirmed that selection for shorter, southern-type CDL decreases female diapausing rate in non-circadian photoperiods. Overall, our study shows that D. montana females measure night length quantitatively, that the photoperiodic counter may play a prominent but slightly different role in extra short and extra long photoperiods and that northern strains show high stability against perturbations in the photoperiod length and in the presence of LD cycles. These features are best explained by the quantitative versions of the damped external coincidence model. peerReviewed