16 research outputs found

    Paternity and Dominance Loss in Male Breeders: The Cost of Helpers in a Cooperatively Breeding Mammal

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    Paternity insurance and dominance tenure length are two important components of male reproductive success, particularly in species where reproduction is highly skewed towards a few individuals. Identifying the factors affecting these two components is crucial to better understand the pattern of variation in reproductive success among males. In social species, the social context (i.e. group size and composition) is likely to influence the ability of males to secure dominance and to monopolize reproduction. Most studies have analyzed the factors affecting paternity insurance and dominance tenure separately. We use a long term data set on Alpine marmots to investigate the effect of the number of subordinate males on both paternity insurance and tenure of dominant males. We show that individuals which are unable to monopolize reproduction in their family groups in the presence of many subordinate males are likely to lose dominance the following year. We also report that dominant males lose body mass in the year they lose both paternity and dominance. Our results suggest that controlling many subordinate males is energetically costly for dominant males, and those unable to support this cost lose the control over both reproduction and dominance. A large number of subordinate males in social groups is therefore costly for dominant males in terms of fitness

    Operation and performance of the ATLAS semiconductor tracker

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    The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations

    Search for the Standard Model Higgs boson decaying into bb¯ produced in association with top quarks decaying hadronically in pp collisions at √s = 8 TeV with the ATLAS detector

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    A search for Higgs boson production in association with a pair of top quarks (tt¯ H) is performed, where the Higgs boson decays to bb¯, and both top quarks decay hadronically. The data used correspond to an integrated luminosity of 20.3 fb−1 of pp collisions at √s = 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The search selects events with at least six energetic jets and uses a boosted decision tree algorithm to discriminate between signal and Standard Model background. The dominant multijet background is estimated using a dedicated data-driven technique. For a Higgs boson mass of 125 GeV, an upper limit of 6.4 (5.4) times the Standard Model cross section is observed (expected) at 95% confidence level. The best-fit value for the signal strength is μ = 1.6 ± 2.6 times the Standard Model expectation for mH = 125 GeV. Combining all tt¯ H searches carried out by ATLAS at √s = 8 and 7 TeV, an observed (expected) upper limit of 3.1 (1.4) times the Standard Model expectation is obtained at 95% confidence level, with a signal strength μ = 1.7 ± 0.8

    Measurement of the azimuthal anisotropy of charged particles produced in s NN = 5.02 TeV Pb+Pb collisions with the ATLAS detector.

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    Measurements of the azimuthal anisotropy in lead-lead collisions at s NN = 5.02 TeV are presented using a data sample corresponding to 0.49 nb - 1 integrated luminosity collected by the ATLAS experiment at the LHC in 2015. The recorded minimum-bias sample is enhanced by triggers for "ultra-central" collisions, providing an opportunity to perform detailed study of flow harmonics in the regime where the initial state is dominated by fluctuations. The anisotropy of the charged-particle azimuthal angle distributions is characterized by the Fourier coefficients, v 2 - v 7 , which are measured using the two-particle correlation, scalar-product and event-plane methods. The goal of the paper is to provide measurements of the differential as well as integrated flow harmonics v n over wide ranges of the transverse momentum, 0.5  < p T <  60 GeV, the pseudorapidity, | η | <  2.5, and the collision centrality 0-80%. Results from different methods are compared and discussed in the context of previous and recent measurements in Pb+Pb collisions at s NN = 2.76  TeV and 5.02  TeV . In particular, the shape of the p T dependence of elliptic or triangular flow harmonics is observed to be very similar at different centralities after scaling the v n and p T values by constant factors over the centrality interval 0-60% and the p T range 0.5  < p T <  5 GeV

    Search for Higgs boson pair production in the γ γ W W ∗ channel using pp collision data recorded at s = 13 TeV with the ATLAS detector.

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    Searches for non-resonant and resonant Higgs boson pair production are performed in the γ γ W W ∗ channel with the final state of γ γ ℓ ν j j using 36.1  fb - 1 of proton-proton collision data recorded at a centre-of-mass energy of s = 13 TeV by the ATLAS detector at the Large Hadron Collider. No significant deviation from the Standard Model prediction is observed. A 95% confidence-level observed upper limit of 7.7 pb is set on the cross section for non-resonant production, while the expected limit is 5.4 pb. A search for a narrow-width resonance X decaying to a pair of Standard Model Higgs bosons HH is performed with the same set of data, and the observed upper limits on σ ( p p → X ) × B ( X → H H ) range between 40.0 and 6.1 pb for masses of the resonance between 260 and 500 GeV, while the expected limits range between 17.6 and 4.4 pb. When deriving the limits above, the Standard Model branching ratios of the H → γ γ and H → W W ∗ are assumed

    Search for the Higgs boson produced in association with a W boson and decaying to four b-quarks via two spin-zero particles in pp collisions at 13 TeV with the ATLAS detector

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    This paper presents a dedicated search for exotic decays of the Higgs boson to a pair of new spin-zero particles, H → aa, where the particle a decays to b-quarks and has a mass in the range of 20–60 GeV. The search is performed in events where the Higgs boson is produced in association with a W boson, giving rise to a signature of a lepton (electron or muon), missing transverse momentum, and multiple jets from b-quark decays. The analysis is based on the full dataset of pp collisions at √s = 13 TeV recorded in 2015 by the ATLAS detector at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 3.2 fb−1. No significant excess of events above the Standard Model prediction is observed, and a 95% confidence-level upper limit is derived for the product of the production cross section for pp → W H times the branching ratio for the decay H → aa → 4b. The upper limit ranges from 6.2 pb for an a-boson mass ma = 20 GeV to 1.5 pb for ma = 60 GeV

    Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

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    Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

    Search for doubly charged scalar bosons decaying into same-sign W boson pairs with the ATLAS detector.

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    A search for doubly charged scalar bosons decaying into W boson pairs is presented. It uses a data sample from proton-proton collisions corresponding to an integrated luminosity of 36.1 fb - 1 collected by the ATLAS detector at the LHC at a centre-of-mass energy of 13 TeV in 2015 and 2016. This search is guided by a model that includes an extension of the Higgs sector through a scalar triplet, leading to a rich phenomenology that includes doubly charged scalar bosons H ± ± . Those bosons are produced in pairs in proton-proton collisions and decay predominantly into electroweak gauge bosons H ± ± → W ± W ± . Experimental signatures with several leptons, missing transverse energy and jets are explored. No significant deviations from the Standard Model predictions are found. The parameter space of the benchmark model is excluded at 95% confidence level for H ± ± bosons with masses between 200 and 220 GeV

    Visuaalisen ilmeen suunnittelu / Make Up Emma Puhakka

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    Opinnäytetyössä luon visuaalisen ilmeen meikkitaiteilija Emma Puhakalle. Työni taustaksi olen keskittynyt brändäykseen, brändi-ilmeen luomiseen, henkilöbrändäykseen sekä pohtinut myös brändistrategiaa. Suunnittelutyössä toteutan visuaalisen ilmeen asiakkaalleni ja mallinnan uuden ilmeen jalkautumisen eri materiaaleihin. Suunnittelen mm. logon, yrityksen värimaailman, kuosin ja määrittelen typografian. Opinnäytetyöni lopputulos on brändimanuaali, joka pitää sisällään visuaalisen ilmeen ja sen säännöt.In my final thesis I create a visual identity for Make Up Artist Emma Puhakka. In support of my design work I have focused on the brand, creating a personal brand and brand manual. Brand strategy is also one of the main things that I have focused on. In design process I create a visual identity for my client and also show how it works in different materials. Among other things I will design a logo, pattern and define typography and colour palette. The outcome of my final thesis is the brand manual, which includes visual identity and instructions

    Aseellinen toiminta kauppa-aluksia vastaan kansainvälisessä aseellisessa selkkauksessa

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    Tutkimuksen tavoitteena oli selvittää, miten kansainvälinen oikeus sääntelee sodankävijävaltion vaikuttamista vihollisen kauppameriliikenteeseen valtioiden välisen aseellisen selkkauksen aikana. Rajausten perusteella tutkimuksen pääkysymykseksi muotoutui: Miten kansainvälinen oikeus sääntelee sota-alusten aseellista toimintaa kauppa-aluksia vastaan kansainvälisessä aseellisessa selkkauksessa. Osana tutkimusta selvitettiin miten merivyöhykkeet vaikuttavat aseellisen toiminnan sääntöihin ja voiko kauppa-alus suojautua aseelliselta toiminnalta kulkemalla puolueettomalla merialueella. Tutkimus toteutettiin noudattaen eurooppalaista oikeuspositivistista lähestymistapaa. Siinä huomio keskittyy voimassa oleviin oikeussääntöihin, joita tulkitaan sellaisina kuin ne ovat tarkasteluhetkellä. Tähän lähestymistapaan perustuvan tieteisopin tarkoituksena on jäsennellä ongelmaan liittyvistä oikeuslähteistä kokonaisuus, selventää siihen sovellettavien oikeussääntöjen sisältöä tulkinnan avulla, ja näiden perusteella esittää tarkasteltavan ongelman oikeudellinen tila. Oikeuslähteinä käytettiin valtiosopimuksia ja tapaoikeuden käsikirjoja. Oikeuslähteiden tulkinnassa hyödynnettiin niihin liittyviä kommentaareja sekä asiantuntijoiden kirjoituksia. Viime vuosisadan sotien käytäntöä, jossa kauppa-aluksia upotettiin valtavia määriä, voidaan pitää nykyisten merisodankäynnin oikeussääntöjen vastaisena. Kansainvälisen oikeuden asiantuntijoiden tekemä valinta sotilaskohteen määritelmän ilmaisun 'tehokas vaikutus sotatoimiin' liittämisestä osaksi aseellisen toiminnan edellytyksiä kauppa-aluksia vastaan, on parantanut rahtia kuljettavien kauppa-alusten suojaa aseelliselta toiminnalta. Tavanomaista rahtia kuljettava kauppa-alus ei ole sallittu kohde aseelliselle toiminnalle, ellei se ole aseistettu tai tuota tiedustelutietoa asevoimille, kulje vihollisen sota-alusten saattueessa tai vastusta alustarkastusta tai haltuunottoa. Vihollisen taloudelliseen heikentämiseen pyrkivä kauppa-alusten tuhoaminen ei siis ole kansainvälisen oikeuden sääntöjen perusteella sallittua. Puolueettomien valtioiden kauppa-alukset nauttivat lähtökohtaisesti vihollisen kauppa-aluksia parempaa suojaa. Jos puolueeton alus kuljettaa rahtia vihollisen satamaan tai satamasta muodostuvat aseellisen toiminnan säännöt lähes vihollisen kauppa-aluksia vastaaviksi. Puolueettomia kauppa-aluksia koskevissa säännöissä korostuvat vaatimukset kohteen varoittamisesta ennen aseellisen toiminnan aloittamista. Puolueettomien valtioiden talousvyöhykkeet eivät käytännössä rajoita aseellista toimintaa kauppa-aluksia vastaan Itämerellä. Kulkiessaan puolueettoman valtion aluevesillä kauppa-alusta vastaan ei saada kohdistaa aseellista toimintaa. Kauppa-alus voi halutessaan käyttää puolueettoman valtion aluevesiä suojautuakseen aseelliselta toiminnalta. Mikäli Suomi ohjaisi meriliikenteensä kulkemaan puolueettoman merialueen kautta, Suomen toiminta olisi mahdollista tulkita puolueettomuuden loukkaukseksi. Se ei kuitenkaan poistaisi kauppa-aluksilta puolueettoman merialueen aikaansaamaa suojaa
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