80 research outputs found

    Seasonal detours by soaring migrants shaped by wind regimes along the East Atlantic Flyway

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    1. Avian migrants often make substantial detours between their seasonal destinations. It is likely some species do this to make the most of predictable wind regimes along their respective flyways. We test this hypothesis by studying orientation behaviour of a long-distance soaring migrant in relation to prevailing winds along the East Atlantic Flyway. 2. We tracked 62 migratory journeys of 12 adult European Honey Buzzards Pernis apivorus with GPS loggers. Hourly fixes were annotated with local wind vectors from a global atmospheric model to determine orientation behaviours with respect to the buzzards’ seasonal goal destinations. This enabled us to determine hot spots where buzzards overdrifted and overcompensated for side winds. We then determined whether winds along the buzzards’ detours differed from winds prevailing elsewhere in the flyway. 3. Honey Buzzards cross western Africa using different routes in autumn and spring. In autumn, they overcompensated for westward winds to circumvent the Atlas Mountains on the eastern side and then overdrifted with south-westward winds while crossing the Sahara. In spring, however, they frequently overcompensated for eastward winds to initiate a westward detour at the start of their journey. They later overdrifted with side winds north-westward over the Sahel and north-eastward over the Sahara, avoiding adverse winds over the central Sahara. 4. We conclude that Honey Buzzards make seasonal detours to utilize more supportive winds further en route and thereby expend less energy while crossing the desert. Lifelong tracking studies will be helpful to elucidate how honey buzzards and other migrants learn complex routes to exploit atmospheric circulation patterns from local to synoptic scales

    Regional and seasonal flight speeds of soaring migrants and the role of weather conditions at hourly and daily scales

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    Given that soaring birds travel faster with supportive winds or in good thermal soaring conditions, we expect weather conditions en route of migration to explain commonly observed regional and seasonal patterns in the performance of soaring migrants. We used GPS-loggers to track 13 honey buzzards and four Montagu's harriers for two to six migrations each. We determined how tailwinds, crosswinds, boundary layer height (a proxy for thermal convection) and precipitation affected hourly speeds, daily distances and daily mean speeds with linear regression models. Honey buzzards mostly travel by soaring while Montagu's harriers supplement soaring with flapping. Therefore, we expect that performance of harriers will be less affected by weather than for buzzards. Weather conditions explained between 30 and 50% of variation in migration performance of both species. Tailwind had the largest effect on hourly speeds, daily mean speeds and daily travel distances. Honey buzzards travelled significantly faster and farther, and Montagu's harriers non-significantly faster, under better convective conditions. Honey buzzards travelled at slower speeds and shorter distances in crosswinds, whereas harriers maintained high speeds in crosswinds. Weather conditions varied between regions and seasons, and this variation accounted for nearly all regional and seasonal variation in flight performance. Hourly performance was higher than predicted at times when we suspect birds had switched to intermittent or continuous flapping flight, for example during sea-crossings. The daily travel distance of Montagu's harriers was determined to a significant extent by their daily travel time, which differed between regions, possibly also due to weather conditions. We conclude with the implications of our work for studies on migration phenology and we suggest an important role for high-resolution telemetry in understanding migratory behavior across entire migratory journeys

    Regulatory Approaches to Managing Skilled Migration: Indonesian Nurses in Japan

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    This article examines the Japan–Indonesia Economic Partnership Agreement, an agreement that has allowed Japan to supplement its local healthcare workforce while continuing to sidestep the thorny issue of labour and immigration policy reform and Indonesia to increase its skilled workers’ access to the Japanese labour market at a time when it was making a concerted effort to reorient migrant labour flows away from informal sector occupations. Despite the programme’s many problems, it has contributed to the use of trade agreements as a mechanism for regulating labour migration, and so to the normalisation of migrant labour as a tradable commodity rather than a discrete area of policy-making, with all the attendant risks that normalisation brings

    Interrogating Associations Between Polygenic Liabilities and Electroconvulsive Therapy Effectiveness

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    Background: Electroconvulsive therapy (ECT) is the most effective treatment for severe major depressive episodes (MDEs). Nonetheless, firmly established associations between ECT outcomes and biological variables are currently lacking. Polygenic risk scores (PRSs) carry clinical potential, but associations with treatment response in psychiatry are seldom reported. Here, we examined whether PRSs for major depressive disorder, schizophrenia (SCZ), cross-disorder, and pharmacological antidepressant response are associated with ECT effectiveness. Methods: A total of 288 patients with MDE from 3 countries were included. The main outcome was a change in the 17-item Hamilton Depression Rating Scale scores from before to after ECT treatment. Secondary outcomes were response and remission. Regression analyses with PRSs as independent variables and several covariates were performed. Explained variance (R 2) at the optimal p-value threshold is reported. Results: In the 266 subjects passing quality control, the PRS-SCZ was positively associated with a larger Hamilton Depression Rating Scale decrease in linear regression (optimal p-value threshold = .05, R 2 = 6.94%, p < .0001), which was consistent across countries: Ireland (R 2 = 8.18%, p = .0013), Belgium (R 2 = 6.83%, p = .016), and the Netherlands (R 2 = 7.92%, p = .0077). The PRS-SCZ was also positively associated with remission (R 2 = 4.63%, p = .0018). Sensitivity and subgroup analyses, including in MDE without psychotic features (R 2 = 4.42%, p = .0024) and unipolar MDE only (R 2 = 9.08%, p < .0001), confirmed the results. The other PRSs were not associated with a change in the Hamilton Depression Rating Scale score at the predefined Bonferroni-corrected significance threshold. Conclusions: A linear association between PRS-SCZ and ECT outcome was uncovered. Although it is too early to adopt PRSs in ECT clinical decision making, these findings strengthen the positioning of PRS-SCZ as relevant to treatment response in psychiatry

    Rhodiola rosea L.:from golden root to green cell factories

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    Tandheelkundige behandeling en antitrombotica

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    Patiënten die antitrombotica gebruiken, lopen risico’s op complicaties bij invasieve behandelingen. Bijna alle (98%) tandartsen houden hier in meer of mindere mate rekening mee en 92% heeft daarover wel eens overleg met andere zorgverleners. De kennis over antitrombotica kan echter verbeterd worden

    Bloedige ingrepen bij patiënten met antitrombotica: nieuwe inzichten

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    Wat moet een behandelaar doen als een patiënt een invasieve tandheelkundige ingreep moet ondergaan terwijl hij of zij antitrombotica gebruikt? Moet men stoppen met de medicatie vóór de ingreep met het risico dat de patiënt opnieuw trombosecomplicaties krijgt, of de procedure uitvoeren zonder aanpassing van deze medicijnen? Welk risico is er dan op nabloedingen? Uit recent onderzoek blijkt dat het tijdelijk staken van antitrombotica in veel gevallen niet noodzakelijk is en de patiënt zelfs schade kan berokkenen. Tandartsen hebben de afgelopen decennia tal van wisselende aanbevelingen gekregen. In dit artikel worden nieuwe onderzoeken op dit terrein samengevat en besproken. De auteurs pleiten voor de ontwikkeling van een klinische evidence-based praktijkrichtlijn
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