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Results are presented on the phytoplankton species compositionand abundance from bottle samples collected in September 1989near the confluence of the Brazil and Malvinas currents offArgentina. The phytoplankton assemblages were dominated by diatomsand dinoflagellates. A surface diatom bloom was found alongthe west side of the Brazil Current, and was dominated by Thalassiosiradelicatula Ostenfeld emend. Hasle (cell numbers up to 5.5 x105 cells 1–1) The bloom was associated with strong temperaturegradients separating Brazil and Malvinas waters, and with thepresence of a cyclonic eddy near the confluence of the currents.These features were detected in satellite imagery coincidentwith the in situ sampling dates.  相似文献   
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Several studies have demonstrated that chewing can be regarded as a preventive measure for cognitive impairment, whereas masticatory deficiency, associated with soft-diet feeding, is a risk factor for the development of dementia. At present the link between orofacial sensorimotor activity and cognitive functions is unknown. In subjects with unilateral molar loss we have shown asymmetries in both pupil size and masticatory muscles electromyographic (EMG) activity during clenching: the molar less side was characterized by a lower EMG activity and a smaller pupil. Since implant-prostheses, greatly reduced both the asymmetry in EMG activity and in pupil’s size, trigeminal unbalance, leading to unbalance in the activity of the Locus Coeruleus (LC), may be responsible for the pupil’s asymmetry. According to the findings obtained in animal models, we propose that the different activity of the right and left LC may induce an asymmetry in brain activity, thus leading to cognitive impairment. According to this hypothesis, prostheses improved the performance in a complex sensorimotor task and increased the mydriasis associated with haptic tasks. In conclusion, the present study indicates that the implant-prosthesis therapy, which reduces the unbalance of trigeminal proprioceptive afferents and the asymmetry in pupil’s size, may improve arousal, boosting performance in a complex sensorimotor task.  相似文献   
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Plasmodium vivax is the most widely distributed human parasite and the main cause of human malaria outside the African continent. However, the knowledge about the genetic variability of P. vivax is limited when compared to the information available for P. falciparum. We present the results of a study aimed at characterizing the genetic structure of P. vivax populations obtained from pregnant women from different malaria endemic settings. Between June 2008 and October 2011 nearly 2000 pregnant women were recruited during routine antenatal care at each site and followed up until delivery. A capillary blood sample from the study participants was collected for genotyping at different time points. Seven P. vivax microsatellite markers were used for genotypic characterization on a total of 229 P. vivax isolates obtained from Brazil, Colombia, India and Papua New Guinea. In each population, the number of alleles per locus, the expected heterozygosity and the levels of multilocus linkage disequilibrium were assessed. The extent of genetic differentiation among populations was also estimated. Six microsatellite loci on 137 P. falciparum isolates from three countries were screened for comparison. The mean value of expected heterozygosity per country ranged from 0.839 to 0.874 for P. vivax and from 0.578 to 0.758 for P. falciparum. P. vivax populations were more diverse than those of P. falciparum. In some of the studied countries, the diversity of P. vivax population was very high compared to the respective level of endemicity. The level of inter-population differentiation was moderate to high in all P. vivax and P. falciparum populations studied.  相似文献   
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Combined torrefaction and pelletization is used to increase the fuel value of biomass by increasing its energy density and improving its handling and combustion properties. In the present study, a single-pellet press tool was used to screen for the effects of pellet die temperature, moisture content, additive addition, and the degree of torrefaction on the pelletizing properties and pellet quality, i.e., density, static friction, and pellet strength. Results were compared with pellet production using a bench-scale pelletizer. The results indicate that friction is the key factor when scaling up from single-pellet press to bench-scale pelletizer. Tuning moisture content or increasing the die temperature did not ease the pellet production of torrefied wood chips significantly. The addition of rapeseed oil as a lubricant reduced the static friction by half and stabilized pellet production; however, the pellet quality, strength, and density were negatively affected. The pellets produced from pine wood torrefied at 250 and 280 °C were shorter than pellets produced from untreated wood and their quality did not match conventional wood pellet standards. However, the heating value of the torrefied pellets was higher and the particle size distribution after grinding the pellets was more uniform compared to conventional wood pellets.  相似文献   
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Homologous recombination requires nucleolytic degradation (resection) of DNA double‐strand break (DSB) ends. In Saccharomyces cerevisiae, the MRX complex and Sae2 are involved in the onset of DSB resection, whereas extensive resection requires Exo1 and the concerted action of Dna2 and Sgs1. Here, we show that the checkpoint protein Rad9 limits the action of Sgs1/Dna2 in DSB resection by inhibiting Sgs1 binding/persistence at the DSB ends. When inhibition by Rad9 is abolished by the Sgs1‐ss mutant variant or by deletion of RAD9, the requirement for Sae2 and functional MRX in DSB resection is reduced. These results provide new insights into how early and long‐range resection is coordinated.  相似文献   
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AimsThe aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma.ResultsThe ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl methacrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS.ConclusionsWe detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions.  相似文献   
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