224 research outputs found
Spatial analysis of BSE cases in the Netherlands
<p>Abstract</p> <p>Background</p> <p>In many of the European countries affected by Bovine Spongiform Encephalopathy (BSE), case clustering patterns have been observed. Most of these patterns have been interpreted in terms of heterogeneities in exposure of cattle to the BSE agent. Here we investigate whether spatial clustering is present in the Dutch BSE case data.</p> <p>Results</p> <p>We have found three spatial case clusters in the Dutch BSE epidemic. The clusters are geographically distinct and each cluster appears in a different birth cohort. When testing all birth cohorts together, only one significant cluster was detected. The fact that we found stronger spatial clustering when using a cohort-based analysis, is consistent with the evidence that most BSE infections occur in animals less than 12 or 18 months old.</p> <p>Conclusion</p> <p>Significant spatial case clustering is present in the Dutch BSE epidemic. The spatial clusters of BSE cases are most likely due to time-dependent heterogeneities in exposure related to feed production.</p
A practical framework for tracing sources of Salmonella in a pig slaughter plant
Salmonella causes around 30 000 cases of human illness per year in The Netherlands, of which an estimated 25% is caused by pork. Salmonella carrying pigs and resident flora on slaughter equipment are relevant sources of carcass contamination. Although recognized, these sources from which and the routes through which Salmonella is transmitted to the pig carcasses during slaughter are not well understood in a quantitative way
Quantitative exposure to livestock-associated MRSA ST398 of pig slaughterhouse workers
Objectives: To quantify livestock-associated MRSA (LA-MRSA) exposure to workers in pig slaughterhouses and assess associated risk factors for carriage in slaughterhouse workers. Methods: A cross-sectional study in three Dutch pig slaughterhouses was undertaken. Nasal swabs of 341 participants, surface wipes, air, and glove samples were screened for presence of MRSA. MRSA was quantitatively determined on gloves and in air samples by culturing and real-time PCR
Case studies: Tuberculination in pig herds suspected of infection with Mycobacterium avium
Mycobacterium avium, both subspecies hominissuis (MAH) and subsp avium (MAA), are considered a significant zoonotic hazard in pigs. Therefore special attention is given to detect the presence of this hazard in pigs during post mortem meat inspection. Herds delivered at slaughter were monitored on blood antibodies against MAH. Herds with an antibody response against a MAH infection were visited. Initially a questionnaire assessing relevant risk factors for MAH was applied
Cascading effects associated with climate-change-induced conifer mortality in mountain temperate forests result in hot-spots of soil CO 2 emissions
Climate change-induced tree mortality is occurring worldwide, at increasingly larger scales and with increasing frequency. How climate change-induced tree mortality could affect the ecology and carbon (C) sink capacity of soils remains unknown. This study investigated regional-scale drought-induced tree mortality, based on events that occurred after a very dry year (2012) in the Carpathians mountain range (Romania), which caused mortality in three common conifer species: Scots pine, Black pine, and Silver fir. This resulted in hot-spots of biogenic soil CO 2 emissions (soil respiration; Rs). Four to five years after the main mortality event, Rs-related soil CO 2 emissions under dead trees were, on average, 21% (ranging from 18 to 35%) higher than CO 2 emissions under living trees. Total (Rs) and heterotrophic (R H )-related soil CO 2 emissions were strongly related to alterations in the soil environment following tree mortality (e.g. changes in quantity and quality of soil organic matter, microclimate, pH or fine root demography). Moreover, the massive mortality event of 2012 resulted in greater presence of successional vegetation (broadleaf seedlings, shrubland and grasses), which may control the environmental factors that either directly or indirectly affected biotic soil fluxes (Rs and R H ). Besides the well-known direct effects of climate change on soil CO 2 emissions, the cascading effects triggered by climate change-induced tree mortality could also exert a strong indirect impact on soil CO 2 emissions. Overall, climate change-induced tree mortality alters the magnitude of environmental controls on Rs and hence determines how the ecosystem C budget responds to climate change. © 2019 Elsevier LtdThis work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) with the projects VERONICA ( CGL2013-42271-P ) and the project IBERYCA ( CGL2017-84723-P ), and by the Romanian Ministry of Education and Scientific Research through UEFISCDI with the projects TREEMORIS ( PN-II-RU-TE-2014-4-0791 ), NATIvE ( PN-III-P1-1.1-PD-2016-0583 ), and BIOCARB ( PN-III-P1-1.1-TE-2016-1508 ). This research was also supported by the Basque Government through the BERC 2018-2021 program, and by the Spanish Ministry of Economy and Competitiveness (MINECO) through the BC3 MarĂa de Maeztu excellence accreditation ( MDM-2017-0714 ). I.C. Petritan was partially funded by the H2020/ERA-NET/ERA-GAS (Project 82/2017, Mobilizing and monitoring climate positive efforts in forests and forestry, FORCLIMIT ). Many thanks to Cosmin Zgremtia, Ionela Medrea, Andrei Apafaian, Raluca Enescu and Marta Ramos for their valuable help during field campaigns and laboratory work
Tree vigour influences secondary growth but not responsiveness to climatic variability in Holm oak
Many tree species from Mediterranean regions have started to show increased rates of crown defoliation, reduced groth, and dieback associated with the increase in temperatures and changes in the frequency and intensity of drought events experienced during the last decades. In this regard, Quercus ilex L. subsp. ballota (Desf.) (Holm oak), despite being a drought-tolerant species widely distributed in the Mediterranean basin, it has recently started to show acute signs of decline, extended areas from Spain being affected. However, few studies have assessed the role of climatic variability (i.e., temperature, precipitation, and drought) on the decline and resilience of Holm oak. Here, we measured secondary growth of seventy Holm oaks from a coppice stand located in central Spain. Sampled trees had different stages of decline, so they were classified into four vigour groups considering their crown foliar lost: healthy (0%), low defoliated (25%), highly defoliated (25 70%), and dying (70 100%). Our results showed that during the study period (1980 2009) the highly defoliated and dying Holm oaks grew significantly less than their healthy and low defoliated neighbours, suggesting permanent growth reduction in the less vigorous individuals. Despite these differences, all four vigour groups showed similar responses to climatic variations, especially during winter and late spring early summer seasons, and similar resilience after severe drought events, managing to significantly recover to pre-drought growth rates after only two years. Our findings, hence, illustrate that tree vigour influences secondary growth but not responsiveness to climatic variability in Holm oak. Still, as reduced growth rates are frequently associated with the process of tree mortality, we conclude that the less vigorous Holm oaks might not be able to cope with future water stress conditions, leading to increased mortality rates among this emblematic Mediterranean specie
The Dutch multicenter experience of the Endo-Sponge treatment for anastomotic leakage after colorectal surgery
Anastomotic leakage is a feared complication following colorectal surgery and is associated with early and long-term morbidity and mortality. The presacral cavity as the result of leakage can be treated with an endo-sponge (B-Braun Medical). The aim of this study was to assess the effectiveness of endo-sponge treatment of the presacral cavity as the result of anastomotic leakage in the Netherlands. Between July 2006 and April 2008, 16 patients (M/F = 9:7) with median age 64 years (range 19-78 years) who underwent surgery for rectal cancer (n = 13) or ulcerative colitis (n = 3) were treated with the endo-sponge treatment after anastomotic leakage. Of the 16 patients, eight patients started with the endo-sponge treatment within 6 weeks after the initial surgery. In these patients the endo-sponge was placed after a median of 24 days (range 13-39 days) following surgery. In the remaining eight patients the endo-sponge treatment was started later than 6 weeks after the initial surgery. In this group there was a median of 74 days (range 43-1,602 days) between surgery and the start of endo-sponge placement. There was closure in six out of eight patients (75%) in the group that started with the endo-sponge treatment within 6 weeks of surgery compared with three out of eight patients (38%) in the group that started later (p = 0.315). Closure was achieved in a median of 40 (range 28-90) days with a median number of 13 sponge replacements (range 8-17). Endo-sponge placement can be helpful in the treatment for anastomotic leakage after colorectal surgery and might prevent a chronic presacral sinus. However, it is not yet clear if this new treatment modality results in quicker healin
Dietary Supplementation with Soluble Plantain Non-Starch Polysaccharides Inhibits Intestinal Invasion of Salmonella Typhimurium in the Chicken
Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S.Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S.Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1â99.7; P<0.0001). In vitro studies confirmed that plantain NSP (5â10 mg/ml) inhibited adhesion of S.Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64â81); P<0.001) and to primary chick caecal crypts (82% mean inhibition (95% CI, 75â90); P<0.001). Adherence inhibition was shown to be mediated via an effect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis
Growth and resilience responses of Scots pine to extreme droughts across Europe depend on predrought growth conditions
Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by treesâ phenotypic variability, which is, in turn, affected by long-term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree-level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree-, site-, and drought-related factors and their interactions driving the tree-level resilience to extreme droughts. We used a tree-ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2, 800Â km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid-elevation and low productivity sites from 1980â1999 to 2000â2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree-level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long-term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation
Exploring the logic of mobile search
After more than a decade of development work and hopes, the usage of mobile Internet has finally taken off. Now, we are witnessing the first signs of evidence of what might become the explosion of mobile content and applications that will be shaping the (mobile) Internet of the future. Similar to the wired Internet, search will become very relevant for the usage of mobile Internet. Current research on mobile search has applied a limited set of methodologies and has also generated a narrow outcome of meaningful results. This article covers new ground, exploring the use and visions of mobile search with a users' interview-based qualitative study. Its main conclusion builds upon the hypothesis that mobile search is sensitive to a mobile logic different than today's one. First, (advanced) users ask for accessing with their mobile devices the entire Internet, rather than subsections of it. Second, success is based on new added-value applications that exploit unique mobile functionalities. The authors interpret that such mobile logic involves fundamentally the use of personalised and context-based services
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