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Background
The 2009 A/H1N1 influenza pandemic has received a great deal of attention from public health authorities. Our study examines whether this pandemic and the resulting public health measures could have impacted acute diarrhea, a prevalent, highly transmissible and historically monitored disease.Methods
Using augmentation procedures of national data for the previous five years (2004–2009), we estimated the expected timing and incidence of acute diarrhea in France in 2009–2010 and evaluated differences with the observed. We also reviewed national hand gels for the same period.Findings
Number of episodes of acute diarrhea in France in 2009–2010 was significantly lower than expected until the third week of December (−24%, 95% CI [−36%; −9%]), then significantly higher (+40%, 95% CI [22%; 62%]), leading to a surplus of 574,440 episodes. The epidemic was delayed by 5 weeks with a peak 1.3 times higher than expected. Hand-gels sales inversely correlated with incidence of both influenza-like illness and acute diarrheal disease. Among individuals >65 yo, no excess cases of influenza and no excess rebound in acute diarrhea were observed, despite similar delay in the onset of the seasonal diarrheal epidemic.Interpretation
Our results suggest that at least one endemic disease had an unexpected behavior in 2009–2010. Acute diarrhea seems to have been controlled during the beginning of the pandemic in all age groups, but later peaked higher than expected in the younger population. The all-age delay in seasonal onset seems partly attributable to hand-gels use, while the differential magnitude of the seasonal epidemic between young and old, concurrent for both influenza and acute diarrhea, is compatible with disease interaction. 相似文献63.
Liu Yuan Luo Cong Zhang Xiu-Juan Lu Xin-Xi Yu Hai-Xia Xie Xiao-Jie Fan Zhi-Yi Mo Xiao He Xin-Hua 《Plant Cell, Tissue and Organ Culture》2020,143(1):219-228
Plant Cell, Tissue and Organ Culture (PCTOC) - CONSTANS (CO)/CONSTANS-like (COL) genes play an important role in the photoperiodic flowering pathway. However, the functional roles of the CO/COL... 相似文献
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Abstract We present a “force-biased” algorithm for generating the irregular close packing of hard spheres. The algorithm is partly based on Jodrey and Tory's ideas [9] and incorporates methods from Molecular Dynamics. Packings generated by means of the two algorithms are consistent up to final packing fraction of 0.65, which seems to be the limit density of Jodrey and Tory's method. Significantly higher densities (up to 0.71) can be achieved for small numbers of spheres by the force-biased algorithm. However the shape of the radial and angle distribution functions implies that a partial short-range ordering occurs in packings of those densities. 相似文献
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Degradation kinetics of biochar from pyrolysis and hydrothermal carbonization in temperate soils 总被引:2,自引:0,他引:2
Mo Bai Burkhard Wilske Franz Buegger Jürgen Esperschütz Claudia Irene Kammann Christian Eckhardt Martin Koestler Philipp Kraft Martin Bach Hans-Georg Frede Lutz Breuer 《Plant and Soil》2013,372(1-2):375-387
Background and Aims
Estimates of biochar residence times in soils range over three orders of magnitude. We present the first direct comparison between the biodegradation of a char from hydrothermal carbonization (htcBC) and pyrolysis (pyrBC) with high temporal resolution.Methods
Mineralization of the biochars and their shared Miscanthus feedstock in three soils was determined directly by the 13CO2 efflux using a novel method incorporating wavelength scanned cavity ring-down spectroscopy. Biochar half-life (t1/2) was estimated with three empirical models.Results
(1) The htcBC was readily biodegradable, whereas pyrBC was more recalcitrant. (2) Cumulative degradation of both biochars increased with soil organic carbon and nitrogen content. (3) The corrected Akaike information criterion (AICC) showed an overall preference for the double exponential model (DEM) reflecting a labile and a recalcitrant C-pool, over the first-order degradation model (FODM) and a logarithmic model. (4) The DEM resulted in t1/2 ranging from 19.7–44.5, 0.7–2.1 and 0.8–1.3 years for pyrBC, htcBC and feedstock, respectively.Conclusion
The degradation was rather similar between feedstock and htcBC but one order of magnitude slower for pyrBC. The AICC preferred FODM in two cases, where the DEM parameters indicated no distinction between a labile and recalcitrant carbon pool. 相似文献68.
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Tao Zhang Jianbing Mo Qiong Shi Xianfeng Zhang Maochun Yuan Long Chen Xueqiang Mao Rutong Yu Xiuping Zhou 《Journal of neurochemistry》2013,125(5):698-712
Geranylgeranyltransferase I (GGT) is a prenyltransferase that mediates lipid modification of Rho small GTPases, such as Rho, Rac, and Cdc42, which are important for neuronal synaptogenesis. Although GGT is expressed in brain extensively, the function of GGT in central nerves system is largely unknown so far. We have previously demonstrated that GGT promotes the basal and neuronal activity and brain‐derived neurotrophic factor (BDNF)‐induced dendritic morphogenesis of cultured hippocampal neurons and cerebellar slices. This study is to explore the function and mechanism of GGT in neuronal synaptogenesis. We found that the protein level and activity of GGT gradually increased in rat hippocampus from P7 to P28 and subcellular located at synapse of neurons. The linear density of Synapsin 1 and post‐synaptic density protein 95 increased by over‐expression of GGT β, while reduced by inhibition or down‐regulation of GGT. In addition, GGT and its known substrate Rac was activated by BDNF, which promotes synaptogenesis in cultured hippocampal neurons. Furthermore, BDNF‐induced synaptogenesis was eliminated by GGT inhibition or down‐regulation, as well as by non‐prenylated Rac1 over‐expression. Together, our data suggested that GGT mediates BDNF‐induced neuronal synaptogenesis through Rac1 activation. 相似文献