Search results for "Timing"
showing 10 items of 126 documents
Fast-timing study of the l-forbidden 1/2+ -> 3/2+ M1 transition in 129Sn
2016
The levels in 129Sn populated from the β− decay of 129In isomers were investigated at the ISOLDE facility of CERN using the newly commissioned ISOLDE Decay Station (IDS). The lowest 1/2+ state and the 3/2+ ground state in 129Sn are expected to have configurations dominated by the neutron s1/2 (l = 0) and d3/2 (l = 2) single-particle states, respectively. Consequently, these states should be connected by a somewhat slow l-forbidden M1 transition. Using fast-timing spectroscopy we have measured the half-life of the 1/2+ 315.3-keV state, T1/2 = 19(10) ps, which corresponds to a moderately fast M1 transition. Shell-model calculations using the CD-Bonn effective interaction, with standard effect…
Five-year outcomes following timely primary percutaneous intervention, late primary percutaneous intervention, or a pharmaco-invasive strategy in ST-…
2019
Abstract Aims ST-segment elevation myocardial infarction (STEMI) guidelines recommend primary percutaneous coronary intervention (pPCI) as the default reperfusion strategy when feasible ≤120 min of diagnostic ECG, and a pharmaco-invasive strategy otherwise. There is, however, a lack of direct evidence to support the guidelines, and in real-world situations, pPCI is often performed beyond recommended timelines. To assess 5-year outcomes according to timing of pPCI (timely vs. late) compared with a pharmaco-invasive strategy (fibrinolysis with referral to PCI centre). Methods and results The French registry of Acute ST-elevation and non-ST-elevation Myocardial Infarction (FAST-MI) programme c…
Mechanisms of population declines in boreal forest grouse
2007
Gilbert Ludwig tutki väitöskirjassaan, miksi kanalinnut ovat vähentyneet talousmetsissä. Suomen metsäkanalintukannat ovat vähentyneet merkittävästi viimeisen 40 vuoden ajan. Pesiin ja poikasiin kohdistuvaa saalistusta on pidetty tärkeimpänä syynä kanalintukantojen laskuun. Hakkuiden ja nuorten metsien osuuden lisääntymisen on katsottu lisänneen myyräkantoja ja niitä syöviä petoja, kuten kettuja, lisäten näin myös kanalintujen pesiin ja poikasiin kohdistuvaa saalistusta. Vuosikymmenten aikana laskenut poikastuotto on keskeisessä roolissa kanalintukantojen laskussa. - Ainakaan teerellä vuotuinen aikuiskuolleisuus ei ole lainkaan lisääntynyt. Hengissäsäilyminen on päinvastoin jopa parantunut, …
Timing an Accreting Millisecond Pulsar: Measuring the Accretion Torque in IGR J00291+5934
2006
We performed a timing analysis of the fastest accreting millisecond pulsar IGR J00291+5934 using RXTE data taken during the outburst of December 2004. We corrected the arrival times of all the events for the orbital (Doppler) effects and performed a timing analysis of the resulting phase delays. In this way we have the possibility to study, for the first time in this class of sources, the spin-up of a millisecond pulsar as a consequence of accretion torques during the X-ray outburst. The accretion torque gives us for the first time an independent estimate of the mass accretion rate onto the neutron star, which can be compared with the observed X-ray luminosity. We also report a revised valu…
Data from: Daphnia invest in sexual reproduction when its relative costs are reduced
2018
The timing of sex in facultatively sexual organisms is critical to fitness, due to the differing demographic consequences of sexual vs. asexual reproduction. In addition to the costs of sex itself, an association of sex with the production of dormant life stages also influences the optimal use of sex, especially in environments where resting eggs are essential to survive unfavourable conditions. Here we document population dynamics and the occurrence of sexual reproduction in natural populations of Daphnia magna across their growing season. The frequency of sexually reproducing females and males increased with population density and with decreasing asexual clutch sizes. The frequency of sex…
Bean goose migration shows a long-term temporal shift to earlier spring, but not to later autumn migration in Finland
2023
Ilmastonmuutos vaatii eliöitä mukauttamaan perinnöllisiä tai opittuja käyttäytymismallejaan muuttuviin ympäristöolosuhteisiin. Erityisen alttiita muutoksille voi olla erilaisten habitaattien välillä muuttavat linnut, joiden selviytyminen on yhteydessä muuton onnistuneeseen ajoittamiseen. Tässä tutkimuksessa käytimme metsähanhesta (Anser fabalis) avoimeen lintutietopalveluun, Tiiraan (tiira.fi – BirdLife Suomi), kerättyjä havaintoja selvittääksemme, onko lajin muuton ajoituksessa tapahtunut muutosta viimeisten 40 vuoden aikana. Lisäksi selvitimme ajoituksen yhteyttä muuton aikaiseen suursäätilaan käyttämällä Pohjois-Atlantin suursäätilaa kuvaavaa NAO-indeksiä. Tutkitulla ajanjaksolla 1978–20…
Germination Pattern of Chamaerops humilis Seed after Short-Time Storage
2015
Dwarf fan palm (Chamaerops humilis) plays an important ecological role in the thermo Mediterranean vegetation stage, both in woodlands, xerophitic shrub communities and degraded ecosystems. Dwarf fan palm is typically propagated from seeds. Whereas other palm species show reduced germination after few months of seed storage, no information is available on the effects of storage time on seed germinability . We examined the germination pattern of dwarf palm seeds aged after a storage of four, six or eight months in comparison to fresh seed (control). A covariance analysis was performed to test the effect of time within seed-storage treatment. The germination patterns were significantly fitted…
Sex Allocation Theory for Facultatively Sexual Organisms Inhabiting Seasonal Environments: The Importance of Bet Hedging
2018
Adaptive explanations for dormancy often invoke bet hedging, where reduced mean fitness can be adaptive if it associates with reduced fitness variance. Sex allocation theory typically ignores variance effects and focuses on mean fitness. For many cyclical parthenogens, these themes become linked, as only sexually produced eggs undergo the dormancy needed to survive harsh conditions. We ask how sex allocation and the timing of sex evolve when this constraint exists in the form of a trade-off between asexual reproduction and sexual production of dormant eggs—the former being crucial for within-season success and the latter for survival across seasons. We show that male production can be tempo…
Data from: Low fitness at low latitudes: wintering in the tropics increases migratory delays and mortality rates in an Arctic breeding shorebird
2020
1. Evolutionary theories of seasonal migration generally assume that the costs of longer migrations are balanced by benefits at the non-breeding destinations. 2. We tested, and rejected, the null hypothesis of equal survival and timing of spring migration for High Arctic breeding sanderling Calidris alba using six and eight winter destinations between 55° N and 25° S, respectively. 3. Annual apparent survival was considerably lower for adult birds wintering in tropical West-Africa (Mauritania: 0.74 and Ghana: 0.75) than in three European sites (0.84, 0.84 and 0.87) and in subtropical Namibia (0.85). Moreover, compared with adults, second calendar-year sanderlings in the tropics, but not in …
Timing the information system upgrade
2010
A system upgrade requires careful planning as its implications to organizational systems might be enormous. Although in IS literature the requirements and process of systems upgrade have been discussed, the timing when to upgrade and what factors guide it has been of lesser interest. Consequently, in this paper we focus on information systems upgrading and its timing from the perspective of the user organization. Upgrading is enabled by the availability of a new software version. When to upgrade, meanwhile, is determined by the business interests of the customer organization, business calendar, development projects, and the vendor. These factors were identified by interviewing 14 IT manager…