BackgroundWeb queries are now widely used for modeling, nowcasting and forecasting influenza-like illness (ILI). However, given that ILI attack rates vary significantly across ages, in terms of both magnitude and timing, little is known about whether the association between ILI morbidity and ILI-related queries is comparable across different age-groups. The present study aimed to investigate features of the association between ILI morbidity and ILI-related query volume from the perspective of age.MethodsSince Google Flu Trends is unavailable in Italy, Google Trends was used to identify entry terms that correlated highly with official ILI surveillance data. All-age and age-class-specific modeling was performed by means of linear models with generalized least-square estimation. Hold-out validation was used to quantify prediction accuracy. For purposes of comparison, predictions generated by exponential smoothing were computed.ResultsFive search terms showed high correlation coefficients of > .6. In comparison with exponential smoothing, the all-age query-based model correctly predicted the peak time and yielded a higher correlation coefficient with observed ILI morbidity (.978 vs. .929). However, query-based prediction of ILI morbidity was associated with a greater error. Age-class-specific query-based models varied significantly in terms of prediction accuracy. In the 0–4 and 25–44-year age-groups, these did well and outperformed exponential smoothing predictions; in the 15–24 and ≥ 65-year age-classes, however, the query-based models were inaccurate and highly overestimated peak height. In all but one age-class, peak timing predicted by the query-based models coincided with observed timing.ConclusionsThe accuracy of web query-based models in predicting ILI morbidity rates could differ among ages. Greater age-specific detail may be useful in flu query-based studies in order to account for age-specific features of the epidemiology of ILI. 相似文献
Artificial lighting allows humans to be active at night, but has many unintended consequences, including interference with ecological processes, disruption of circadian rhythms and increased exposure to insect vectors of diseases. Although ultraviolet and blue light are usually most attractive to arthropods, degree of attraction varies among orders. With a focus on future indoor lighting applications, we manipulated the spectrum of white lamps to investigate the influence of spectral composition on number of arthropods attracted. We compared numbers of arthropods captured at three customizable light-emitting diode (LED) lamps (3510, 2704 and 2728 K), two commercial LED lamps (2700 K), two commercial compact fluorescent lamps (CFLs; 2700 K) and a control. We configured the three custom LEDs to minimize invertebrate attraction based on published attraction curves for honeybees and moths. Lamps were placed with pan traps at an urban and two rural study sites in Los Angeles, California. For all invertebrate orders combined, our custom LED configurations were less attractive than the commercial LED lamps or CFLs of similar colour temperatures. Thus, adjusting spectral composition of white light to minimize attracting nocturnal arthropods is feasible; not all lights with the same colour temperature are equally attractive to arthropods. 相似文献
NDP reductase activity can be inhibited either by treatment with hydroxyurea or by incubation of an nrdAts mutant strain at the non-permissive temperature. Both methods inhibit replication, but experiments on these two types of
inhibition yielded very different results. The chemical treatment immediately inhibited DNA synthesis but did not affect the
cell and nucleoid appearance, while the incubation of an nrdA101 mutant strain at the non-permissive temperature inhibited DNA synthesis after more than 50 min, and resulted in aberrant
chromosome segregation, long filaments, and a high frequency of anucleate cells. These phenotypes are not induced by SOS.
In view of these results, we suggest there is an indirect relationship between NDP reductase and the chromosome segregation
machinery through the maintenance of the proposed replication hyperstructure. 相似文献
MOTIVATION: Efficient fitting tools are needed to take advantage of a fast growth of atomic models of protein domains from crystallography or comparative modeling, and low-resolution density maps of larger molecular assemblies. Here, we report a novel fitting algorithm for the exhaustive and fast overlay of partial high-resolution models into a low-resolution density map. The method incorporates a fast rotational search based on spherical harmonics (SH) combined with a simple translational scanning. RESULTS: This novel combination makes it possible to accurately dock atomic structures into low-resolution electron-density maps in times ranging from seconds to a few minutes. The high-efficiency achieved with simulated and experimental test cases preserves the exhaustiveness needed in these heterogeneous-resolution merging tools. The results demonstrate its efficiency, robustness and high-throughput coverage. AVAILABILITY: http://sbg.cib.csic.es/Software/ADP_EM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online. 相似文献
The olfactory system, particularly the olfactory epithelium, presents a unique opportunity to study the regenerative capabilities of the brain, because of its ability to recover after damage. In this study, we ablated olfactory sensory neurons with methimazole and followed the anatomical and functional recovery of circuits expressing genetic markers for I7 and M72 receptors (M72-IRES-tau-LacZ and I7-IRES-tau-GFP). Our results show that 45 days after methimazole-induced lesion, axonal projections to the bulb of M72 and I7 populations are largely reestablished. Furthermore, regenerated glomeruli are re-formed within the same areas as those of control, unexposed mice. This anatomical regeneration correlates with functional recovery of a previously learned odorant-discrimination task, dependent on the cognate ligands for M72 and I7. Following regeneration, mice also recover innate responsiveness to TMT and urine. Our findings show that regeneration of neuronal circuits in the olfactory system can be achieved with remarkable precision and underscore the importance of glomerular organization to evoke memory traces stored in the brain. 相似文献
Unare Lagoon is one of the most important fishery coastal ecosystems in Venezuela. For the past 10 years, changes in its hydrological regime have affected the physiochemical characteristics of the water with important consequences on its faunal composition and abundance. An example of such variation is the abundant presence ofa fish species, Gobioides broussonnetii, recently registered in this ecosystem. The ecology of this species must be studied to identify new ecological processes occurring in the lagoon. Detritus is the most important component of the G. broussonnetii diet, followed by plant and animal items. The species is a primary detritivorous consumer and this may be associated with its activity pattern (morning): It may be an occasional visitor because it was not captured regularly in the monthly samplings. 相似文献
Ultrafiltration is an attractive downstream processing technique for concentrating enzymes and could be considered the primary step of purification. However, the efficiency of this process is often limited by protein fouling and shear-induced enzyme inactivation, which decreases permeate flux and results in the loss of enzyme activity. Although the rejection of phytase was higher than 99%, the loss of the enzyme activity was 14% during operation, indicating that the shear forces generated in the filter have significant influences on the enzyme activity. Two preparations using glycerol (25% and 35%, v/v) as a cryo-protecting agent at different temperatures were studied. The preparation containing 35% glycerol retained 70% of the initial enzyme activity at 70 °C after 1 h and had more than 3 and 6 months storage half-life at 29 °C and 4 °C, respectively. 相似文献
Upon stimulation of cells with interleukin-1 (IL-1) the IL-1 receptor type I (IL-1RI) associated kinase-1 (IRAK-1) transiently associates to and dissociates from the IL-1RI and thereafter translocates into the nucleus. Here we show that nuclear translocation of IRAK-1 depends on its kinase activity since translocation was not observed in EL-4 cells overexpressing a kinase negative IRAK-1 mutant (EL-4(IRAK-1-K239S)). IRAK-1 itself, an endogenous substrate with an apparent molecular weight of 24kDa (p24), and exogenous substrates like histone and myelin basic protein are phosphorylated by nuclear located IRAK-1. Phosphorylation of p24 cannot be detected in EL-4(IRAK-1-K239S) cells. IL-1-dependent recruitment of IRAK-1 to the IL-1RI and subsequent phosphorylation of IRAK-1 is a prerequisite for nuclear translocation of IRAK-1. It is therefore concluded that intracellular localization of IRAK-1 depends on its kinase activity and that IRAK-1 may also function as a kinase in the nucleus as shown by a new putative endogenous substrate. 相似文献
The prion protein (PrP) plays a key role in prion disease pathogenesis. Although the misfolded and pathologic variant of this protein (PrPSC) has been studied in depth, the physiological role of PrPC remains elusive and controversial. PrPC is a cell‐surface glycoprotein involved in multiple cellular functions at the plasma membrane, where it interacts with a myriad of partners and regulates several intracellular signal transduction cascades. However, little is known about the gene expression changes modulated by PrPC in animals and in cellular models. In this article, we present PrPC‐dependent gene expression signature in N2a cells and its implication in the most overrepresented functions: cell cycle, cell growth and proliferation, and maintenance of cell shape. PrPC over‐expression enhances cell proliferation and cell cycle re‐entrance after serum stimulation, while PrPC silencing slows down cell cycle progression. In addition, MAP kinase and protein kinase B (AKT) pathway activation are under the regulation of PrPC in asynchronous cells and following mitogenic stimulation. These effects are due in part to the modulation of epidermal growth factor receptor (EGFR) by PrPC in the plasma membrane, where the two proteins interact in a multimeric complex. We also describe how PrPC over‐expression modulates filopodia formation by Rho GTPase regulation mainly in an AKT‐Cdc42‐N‐WASP‐dependent pathway.
Phototrophic biofilm formation and dynamics result from the interaction between several parameters, including chemical interactions. Some of the secondary metabolites released by microalgae can influence the composition of benthic communities. We determined the effects of decadienal (DD), a polyunsaturated aldehyde produced by diatoms, on a benthic diatom, Fistulifera saprophila. At 5?μg?ml(-1), DD reduced cell motility by 88% and cell adhesion to the substrate by 91%. The effects occurred in less than 30?min. Using a fluorescent probe, we showed that DD could induce nitric oxide (NO) accumulation in F. saprophila cells. Cells exposed to a NO donor presented reduced adhesion and motility, which suggests the involvement of this cellular messenger in the mode of action of DD. Short-term experiments in microcosms showed that the presence of DD on a substrate strongly inhibited biofilm formation. Moreover, when the biofilm was bispecific, DD modified the proportion of the two species present. This indicates that the presence of DD-producing diatoms in a biofilm may favor the presence of certain microalgae at the expense of others. In addition to the effects on adhesion and motility, DD induced the formation of aggregates of F. saprophila cells. Aggregation was independent of NO production. Complementary experiments were performed with two other benthic diatoms, Nitzschia palea and Mayamea atomus. They showed that the effects of DD on adhesion and aggregation were species-dependent. 相似文献