104 research outputs found

    Going south : latitudinal change in mammalian biodiversity in Miocene Eurasia

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    For palaeontologists, the challenge is to reconstruct biodiversity patterns of the past. Mammal richness in grids is used to assess the stability of biodiversity hotspots and document changes over time in Europe for Mammal Neogene units 3 to 11 (19.5 to 7.6 Ma), early to late Miocene. The maps clearly show the patchiness of the fossil record. As the Miocene was an eventful epoch with severe environmental changes, Europe slowly became drier, and more seasonal, both in temperature and precipitation. From the early to middle Miocene an area of high biodiversity moved from higher to lower latitudes, culminating in one of the most remarkable hotspots in the history of mammals: the early late Miocene (Vallesian mammal stage) faunas from the Vallès-Penedès (Catalonia, Spain). Remarkably, the surrounding areas did not exhibit similar richness. During the subsequent Vallesian turnover event (~ 9.7 Ma), the large and small mammal distribution became more equitable and the hotspots less prominent. The richest area was found in the periphery of the humid Miocene ecosystem, which experienced species influx from the drier south. The southward shift was a result of the expansion of the humid area with subsequent closed environments and related mixing of ecosystems, coming to a halt in the late Miocene, when all of Europe became equally open

    Influenza in long-term Dutch travelers in the tropics: Symptoms and infections

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    Background: Influenza is a common infection among travelers, and attack rates are well documented in short-term travelers and holiday makers. Little data exists on long-term, non-expatriate travelers. Methods: This was a prospective mono-centre study of immunocompetent, Dutch travelers aged ≥18 to 64 years. It was conducted at the Public Health Service travel clinic in Amsterdam from December 2008 to September 2011, and included all travelers intending to travel to a tropical or sub-tropical country. Results: Among 602 Dutch long-term travelers to tropical regions, 82 % had protective influenza antibody titres pre-travel. The influenza attack rate of serologically confirmed infection during travel was 15 %, and of symptomatic infection was 6.3 % (fever alone) and 2 % (ILI), respectively. Conclusions: The attack rate in this study is similar to seasonal rates of infection in the general population. Influenza vaccination pre-travel is therefore most important for people at risk of medical complications due to influenza

    The range and extent of the Vallesian Crisis (Late Miocene) : new prospects based on the micromammal record from the Vallès-Penedès basin (Catalonia, Spain)

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    The Vallesian Crisis was initially recognized as a local event, which implied the extinction of certain rodent and artiodactyl genera coinciding with the early/late Vallesian boundary (at 9.7 Ma). Following works increased the range and extent of this event to encompass all Europe and involve a great number of mammal taxa. Here, we analyze the Vallesian rodent and insectivore record of the Vallès-Penedès basin (Catalonia, Spain), where the crisis was first recognized. We show that the quality of the record before the crisis is comparatively much better than afterwards so diversity appears inflated and extinction rates are overrated. Accordingly, we used inferred taxon ranges and rarefaction to calculate new diversity measures independent of sample size. These measures virtually eliminate the Vallesian Crisis, showing that diversity somewhat decreased during the earliest late Vallesian and soon recovered afterwards. This is because it cannot be discarded that several rare taxa, customarily said to have disappeared during the crisis, are in fact present. Amongst the rodents and insectivores, these taxa include genera that are generally rare and show a discontinuous record during the early Vallesian. These are presumed specialists adapted to humid forested environments such as flying squirrels, beavers or certain dormice, most of them being only recorded when the sample size is large enough. Alternatively, these genera may have been associated to very specific habitats which, for an unknown reason, are not sampled during the late Vallesian. Our results cast serious doubts on the very existence of the Vallesian Crisis suggesting that rather than an abrupt event a series of extinctions occurred during a longer time span. It has not been evaluated whether the same pattern is observed in the case of large mammals and in other areas. However, our results show that biases introduced by the quality of the record need to be taken into account when assessing the extent of the event.La Crisis Vallesiense fue inicialmente definida como un fenómeno local que implicó la desaparición de ciertos géneros de roedores y artiodáctilos coincidiendo con el límite entre Vallesiense inferior y superior (hace 9.7 Ma). Trabajos posteriores ampliaron el ámbito y alcance de este evento hasta incluir toda Europa e implicar un gran número de taxones de mamíferos. En este trabajo analizamos el registro Vallesiense de roedores e insectívoros de la cuenca del Vallès-Penedès (Cataluña, España), donde la crisis fue reconocida por primera vez. Se muestra que la calidad del registro fósil con anterioridad a la crisis es comparativamente mucho mejor que la de después de modo que se magnifica la diversidad y se exageran las tasas de extinción. Por lo tanto, se ha utilizado rarefacción y se han inferido rangos estratigráficos a fin de calcular nuevas medidas de diversidad independientes del tamaño de la muestra. Estas medidas eliminan virtualmente la Crisis Vallesiense, mostrando que la diversidad disminuyó a principios del Vallesiense superior para recuperarse poco después a finales de esta edad. Esto es debido a que no podemos descartar que diversos taxones poco abundantes, normalmente citados como víctimas de la crisis, estuvieran de hecho presentes. Entre los roedores e insectívoros dichos taxones incluyen géneros que son generalmente raros y que muestran un registro discontinuo durante el Vallesiense inferior. Se trata de supuestos especialistas adaptados a ambientes boscosos húmedos tales como ardillas voladoras, castores o ciertos lirones, la mayoría de los cuales sólo se encuentran cuando el tamaño de la muestra es lo suficientemente grande. Alternativamente, estos géneros podrían haber estado asociados a hábitats muy específicos que por algún motivo no están siendo muestreados durante el Vallesiense superior. Nuestros resultados cuestionan seriamente la existencia de la Crisis Vallesiense y sugieren que en lugar de un evento abrupto podría tratarse de una serie de extinciones que habrían sucedido durante un período más largo. Queda pendiente de evaluación si el mismo patrón se observa en el caso de los grandes mamíferos y en otras áreas. No obstante nuestros resultados muestran que se deberían tomar en consideración las desviaciones introducidas por la calidad del registro al analizar el alcance de este evento

    Onderzoek naar het terugdringen van korte detenties met behulp van instrumenten:Changing justice gears - Empirische fase

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    Kortdurende detenties, waaronder korte gevangenisstraffen (korter dan zes maanden), kunnen schadelijk zijn en kunnen criminogene effecten hebben. Daders worden weggehaald uit de omgeving die hen op het rechte pad kan houden - woning, werk en wederhelft - terwijl de gevangenistijd te kort is om deel te nemen aan re-integratieprogramma’s. Het leidt tot ongewenste recidivecijfers. Daders die alternatieve straffen krijgen opgelegd, gaan echter minder vaak opnieuw de fout in dan daders die een korte gevangenisstraf opgelegd krijgen. Alternatieve straffen lijken dus uiteindelijk te kunnen leiden tot een veiligere maatschappij dan korte gevangenisstraf. Het doel van het onderzoek was daarom het ontwikkelen van instrumenten die sturen in de richting van alternatieve sancties waardoor het aantal korte gevangenisstraffen zou kunnen verminderen. Op basis van juridisch vooronderzoek zijn twee instrumenten ontwikkeld: Motivate en Discover. 1) Motivate is een instrument waarin men op een visuele manier wordt gestimuleerd om eerst na te denken over afdoening in de vorm van herstel en resocialisatie en pas als ultimum remedium een straf in de vorm van vergelding, afschrikking en onschadelijkmaking te overwegen; 2) Discover is een instrument bestaande uit verschillende nieuwe alternatieve sancties: i) (herstelgerichte) elektronische thuisdetentie, ii) uitbreiding van de taakstraf uren, iii) herstelgerichte taakstraf, en iv) herstelconferenties. In de empirische fase van het onderzoek is nog een derde instrument toegevoegd: 3) informatie over de positieve effecten van alternatieve sancties in vergelijking tot gevangenisstraf. De instrumenten zijn aangescherpt door middel van overleg met wetenschappers en de rechtspraktijk, tijdens een klankbordgroep, een congres over het reduceren van korte gevangenisstraffen en drie ronde tafel sessies met Slachtofferhulp Nederland, Reclassering Nederland en officieren en rechters. Vervolgens hebben we een gerandomiseerd gecontroleerd online interventieonderzoek uitgevoerd onder rechtenstudenten (n=48), officieren (n=23) en rechters (n=25) om te kijken of de instrumenten bijdragen tot minder korte gevangenisstraffen. Deelnemers kregen drie casussen voorgelegd: een fraude-, een mishandelings- en een verkeersdelictscasus. De helft kreeg de drie nieuwe instrumenten aangereikt plus LOVS-oriëntatiepunten of strafvorderingsrichtlijn, de andere helft kreeg alleen de LOVS-oriëntatiepunten of strafvorderingsrichtlijn. Rechtenstudenten die de instrumenten kregen voorgelegd legden in alle drie de casussen minder korte gevangenisstraffen op in vergelijking met rechtenstudenten die alleen de LOVS-oriëntatiepunten kregen aangereikt. Onder officieren en rechters vonden we gemixte resultaten. De instrumenten resulteerden alleen in de fraudecasus tot minder korte gevangenisstraf. In de geweldscasus legden alleen rechters die de nieuwe instrumenten kregen voorgelegd minder korte gevangenisstraf op; bij officieren was er geen verschil tussen de groep die wel of geen instrumenten hadden gekregen. In de verkeerscasus hadden de instrumenten geen invloed op de wijze van sanctioneren, noch bij rechters noch officieren.De meest plausibele verklaring voor het feit dat de instrumenten in de strafrechtspraktijk niet het verwachte effect hadden op sanctionering is dat de online experimentele beïnvloeding niet impactvol genoeg was. De sanctietoepassing is een lange, traditionele praktijk die niet zomaar met een online tool kan worden veranderd. De uitkomsten pleiten voor verder onderzoek naar mogelijke barrières die de professionals in de strafrechtspraktijk kunnen ervaren jegens herstelgericht sanctioneren. Daarnaast is het interessant te onderzoeken of een (uitgebreidere) training van de instrumenten wel het verwachte effect zou kunnen bewerkstelligen op het verminderen van de korte gevangenisstraf. We pleiten tenslotte ook voor meer aandacht voor herstelgericht sanctioneren in het juridisch onderwijs. <br/

    People with Multiple Tattoos and/or Piercings Are Not at Increased Risk for HBV or HCV in The Netherlands

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    BACKGROUND: Although published results are inconsistent, it has been suggested that tattooing and piercing are risk factors for HBV and HCV infections. To examine whether tattooing and piercing do indeed increase the risk of infection, we conducted a study among people with multiple tattoos and/or piercings in The Netherlands who acquired their tattoos and piercings in The Netherlands and/or abroad. METHODS: Tattoo artists, piercers, and people with multiple tattoos and/or piercings were recruited at tattoo conventions, shops (N = 182), and a biannual survey at our STI-outpatient clinic (N = 252) in Amsterdam. Participants were interviewed and tested for anti-HBc and anti-HCV. Determinants of HBV and HCV infections were analysed using logistic regression analysis. RESULTS: The median number of tattoos and piercings was 5 (IQR 2-10) and 2 (IQR 2-4), respectively. Almost 40% acquired their tattoo of piercing abroad. In total, 18/434 (4.2%, 95%CI: 2.64%-6.46%) participants were anti-HBc positive and 1 was anti-HCV positive (0.2%, 95%CI: 0.01%-1.29%). Being anti-HBc positive was independently associated with older age (OR 1.68, 95%CI: 1.03-2.75 per 10 years older) and being born in an HBV-endemic country (OR 7.39, 95%CI: 2.77-19.7). Tattoo- and/or piercing-related variables, like having a tattoo or piercing in an HBV endemic country, surface percentage tattooed, number of tattoos and piercings etc., were not associated with either HBV or HCV. CONCLUSIONS: We found no evidence for an increased HBV/HCV seroprevalence among persons with multiple tattoos and/or piercings, which might be due to the introduction of hygiene guidelines for tattoo and piercing shops in combination with the low observed prevalence of HBV/HCV in the general population. Tattoos and/or piercings, therefore, should not be considered risk factors for HBV/HCV in the Dutch population. These findings imply the importance of implementation of hygiene guidelines in other countries

    Effect of travel on influenza epidemiology

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    To assess the attack and incidence rates for influenza virus infections, during October 2006-October 2007 we prospectively studied 1,190 adult short-term travelers from the Netherlands to tropical and subtropical countries. Participants donated blood samples before and after travel and kept a travel diary. The samples were serologically tested for the epidemic strains during the study period. The attack rate for all infections was 7% (86 travelers) and for influenza-like illness (ILI), 0.8%. The incidence rate for all infections was 8.9 per 100 person-months and for ILI, 0.9%. Risk factors for infection were birth in a non-Western country, age 55-64 years, and ILI. In 15 travelers with fever or ILI, influenza virus infection was serologically confirmed; 7 of these travelers were considered contagious or incubating the infection while traveling home. Given the large number of travelers to (sub)tropical countries, travel-related infection most likely contributes to importation and further influenza spread worldwide

    High and persistent excretion of hepatitis A virus in immunocompetent patients.

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    The duration and level of virus excretion in blood and faeces of patients with hepatitis A virus (HAV) infection were studied in relation to levels of alanine aminotransferase (ALT), disease severity and HAV genotype. Clinical data, blood and faeces were collected from 27 patients with acute hepatitis A (median age: 33 years) for a maximum of 26 weeks. Single blood donations from 55 other patients with acute HAV (median age: 32 years) were also used. Virus loads were quantified by competitive nested RT-PCR. HAV was excreted in faeces for a median period of 81 days after disease onset, with 50% of patients still excreting high levels at Day 36 (2 x 10(6) - 2 x 10(8) copies/ml faeces suspension). Viraemia was detected, but not quantifiable, for a median period of 42 days. In the first 10 days of illness, higher ALT levels were correlated with higher viraemia levels. Comparison of patients infected with genotype 1a with those infected with type 1b did not differ significantly in terms of the duration of HAV excretion or jaundice. In conclusion, faecal excretion of HAV is at a high titre in the first month, perhaps making patients infectious for a longer period than assumed currently. Blood banks should be aware that viraemia may be present for more than 1 month, and genotype did not affect the duration of virus excretion or jaundice

    The Miocene mammal record of the Vallès-Penedès Basin (Catalonia)

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    The land mammal record of the Vallès-Penedès Basin (Catalonia, NE Spain) ranges from the early Miocene (Ramblian) to the late Miocene (Turolian), that is from about 20 to 7 Ma. Here we present an updated review of the mammal succession focusing on biochronology as well as on environmental and faunal changes. Based on faunal similarities with central Europe, we interpret this basin as a transitional zone between the forested environments of northern regions and the more arid landscapes of the inner Iberian Peninsula. The quality of the Vallès-Penedès record and its chronostratigraphic control is clearly better for the late Aragonian and the Vallesian (between 12.6-9.0 Ma), especially for small mammals. Therefore, we analyze small mammal diversity dynamics during this interval. Contrary to previous analyses, which found an abrupt extinction event coinciding with the early/late Vallesian boundary (the Vallesian Crisis), our results show that this pattern is due to uneven sampling. Instead, taxonomic richness slowly decreased since the late Vallesian as a result of a series of extinctions that mostly affected forest-dwelling taxa

    Synchronous vegetation response to the last glacial-interglacial transition in northwest Europe

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    The North Atlantic region experienced abrupt high-amplitude cooling at the onset of the Younger Dryas stadial. However, due to chronological uncertainties in the available terrestrial records it is unclear whether terrestrial ecosystem response to this event was instantaneous and spatially synchronous, or whether regional or time-transgressive lags existed. Here we use new palynological results from a robustly dated lake sediment sequence retrieved from lake Hämelsee (north Germany) to show that vegetation change started at 12,820 cal. yr BP, concurrent with the onset of changes in local climate. A comparison of the Hämelsee results to a compilation of precisely dated palynological records shows instant and, within decadal-scale dating uncertainty, synchronous response of the terrestrial plant community to Late-Glacial climate change across northwest Europe. The results indicate that the environmental impact of climate cooling was more severe than previously thought and illustrates the sensitivity of natural terrestrial ecosystems to external forcing. © 2022, The Author(s)
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