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891.
Stanislav Sobolevsky Izabela Sitko Remi Tachet des Combes Bartosz Hawelka Juan Murillo Arias Carlo Ratti 《PloS one》2016,11(2)
Scientific studies of society increasingly rely on digital traces produced by various aspects of human activity. In this paper, we exploit a relatively unexplored source of data–anonymized records of bank card transactions collected in Spain by a big European bank, and propose a new classification scheme of cities based on the economic behavior of their residents. First, we study how individual spending behavior is qualitatively and quantitatively affected by various factors such as customer’s age, gender, and size of his/her home city. We show that, similar to other socioeconomic urban quantities, individual spending activity exhibits a statistically significant superlinear scaling with city size. With respect to the general trends, we quantify the distinctive signature of each city in terms of residents’ spending behavior, independently from the effects of scale and demographic heterogeneity. Based on the comparison of city signatures, we build a novel classification of cities across Spain in three categories. That classification exhibits a substantial stability over different city definitions and connects with a meaningful socioeconomic interpretation. Furthermore, it corresponds with the ability of cities to attract foreign visitors, which is a particularly remarkable finding given that the classification was based exclusively on the behavioral patterns of city residents. This highlights the far-reaching applicability of the presented classification approach and its ability to discover patterns that go beyond the quantities directly involved in it. 相似文献
892.
893.
Eva del Amo Cristina Esteva Susanna Hernandez-Bou Carmen Galles Marian Navarro Goretti Sauca Alvaro Diaz Paula Gassiot Carmina Marti Nieves Larrosa Pilar Ciruela Mireia Jane Raquel Sá-Le?o Carmen Mu?oz-Almagro Catalan Study Group of Invasive Pneumococcal Disease 《PloS one》2016,11(3)
The aim of this study was to study the serotypes and clonal diversity of pneumococci causing invasive pneumococcal disease in Catalonia, Spain, in the era of 13-valent pneumococcal conjugate vaccine (PCV13). In our region, this vaccine is only available in the private market and it is estimated a PCV13 vaccine coverage around 55% in children. A total of 1551 pneumococcal invasive isolates received between 2010 and 2013 in the Molecular Microbiology Department at Hospital Sant Joan de Déu, Barcelona, were included. Fifty-two serotypes and 249 clonal types—defined by MLST—were identified. The most common serotypes were serotype 1 (n = 182; 11.7%), 3 (n = 145; 9.3%), 19A (n = 137; 8.8%) and 7F (n = 122; 7.9%). Serotype 14 was the third most frequent serotype in children < 2 years (15 of 159 isolates). PCV7 serotypes maintained their proportion along the period of study, 16.6% in 2010 to 13.4% in 2013, whereas there was a significant proportional decrease in PCV13 serotypes, 65.3% in 2010 to 48.9% in 2013 (p<0.01). This decrease was mainly attributable to serotypes 19A and 7F. Serotype 12F achieved the third position in 2013 (n = 22, 6.4%). The most frequent clonal types found were ST306 (n = 154, 9.9%), ST191 (n = 111, 7.2%), ST989 (n = 85, 5.5%) and ST180 (n = 80, 5.2%). Despite their decrease, PCV13 serotypes continue to be a major cause of disease in Spain. These results emphasize the need for complete PCV13 vaccination. 相似文献
894.
Kun Lee Lim Joanne Hewitt Alefiya Sitabkhan John-Sebastian Eden Jennifer Lun Avram Levy Juan Merif David Smith William D. Rawlinson Peter A. White 《PloS one》2016,11(4)
BackgroundNorovirus (NoV) is the major cause of acute gastroenteritis across all age groups. In particular, variants of genogroup II, genotype 4 (GII.4) have been associated with epidemics globally, occurring approximately every three years. The pandemic GII.4 variant, Sydney 2012, was first reported in early 2012 and soon became the predominant circulating NoV strain globally. Despite its broad impact, both clinically and economically, our understanding of the fundamental diversity and mechanisms by which new NoV strains emerge remains limited. In this study, we describe the molecular epidemiological trends of NoV-associated acute gastroenteritis in Australia and New Zealand between January 2013 and June 2014.MethodologyOverall, 647 NoV-positive clinical faecal samples from 409 outbreaks and 238 unlinked cases of acute gastroenteritis were examined by RT-PCR and sequencing. Phylogenetic analysis was then performed to identify NoV capsid genotypes and to establish the temporal dominance of circulating pandemic GII.4 variants. Recombinant viruses were also identified based on analysis of the ORF1/2 overlapping region.FindingsPeaks in NoV activity were observed, however the timing of these epidemics varied between different regions. Overall, GII.4 NoVs were the dominant cause of both outbreaks and cases of NoV-associated acute gastroenteritis (63.1%, n = 408/647), with Sydney 2012 being the most common GII.4 variant identified (98.8%, n = 403/408). Of the 409 reported NoV outbreaks, aged-care facilities were the most common setting in both Western Australia (87%, n = 20/23) and New Zealand (58.1%, n = 200/344) while most of the NoV outbreaks were reported from hospitals (38%, n = 16/42) in New South Wales, Australia. An analysis of a subset of non-GII.4 viruses from all locations (125/239) showed the majority (56.8%, n = 71/125) were inter-genotype recombinants. These recombinants were surprisingly diverse and could be classified into 18 distinct recombinant types, with GII.P16/GII.13 (24% of recombinants) the most common.ConclusionThis study revealed that following its emergence in 2012, GII.4 Sydney 2012 variant continued to be the predominant cause of NoV-associated acute gastroenteritis in Australia and New Zealand between 2013 and 2014. 相似文献
895.
Diego F. Segura Ana L. Nussenbaum Mariana M. Viscarret Francisco Devescovi Guillermo E. Bachmann Juan C. Corley Sergio M. Ovruski Jorge L. Cladera 《PloS one》2016,11(3)
Parasitoids searching for polyphagous herbivores can find their hosts in a variety of habitats. Under this scenario, chemical cues from the host habitat (not related to the host) represent poor indicators of host location. Hence, it is unlikely that naïve females show a strong response to host habitat cues, which would become important only if the parasitoids learn to associate such cues to the host presence. This concept does not consider that habitats can vary in profitability or host nutritional quality, which according to the optimal foraging theory and the preference-performance hypothesis (respectively) could shape the way in which parasitoids make use of chemical cues from the host habitat. We assessed innate preference in the fruit fly parasitoid Diachasmimorpha longicaudata among chemical cues from four host habitats (apple, fig, orange and peach) using a Y-tube olfactometer. Contrary to what was predicted, we found a hierarchic pattern of preference. The parasitism rate realized on these fruit species and the weight of the host correlates positively, to some extent, with the preference pattern, whereas preference did not correlate with survival and fecundity of the progeny. As expected for a parasitoid foraging for generalist hosts, habitat preference changed markedly depending on their previous experience and the abundance of hosts. These findings suggest that the pattern of preference for host habitats is attributable to differences in encounter rate and host quality. Host habitat preference seems to be, however, quite plastic and easily modified according to the information obtained during foraging. 相似文献
896.
Eva Talavera-Garcia Javier Delgado-Lista Antonio Garcia-Rios Nieves Delgado-Casado Purificacion Gomez-Luna Angela Gomez-Gardu?o Francisco Gomez-Delgado Juan F. Alcala-Diaz Elena Yubero-Serrano Carmen Marin Ana I. Perez-Caballero Francisco J. Fuentes-Jimenez Antonio Camargo Fernando Rodriguez-Cantalejo Francisco J. Tinahones Jose M. Ordovas Francisco Perez- Jimenez Pablo Perez-Martinez Jose Lopez-Miranda 《PloS one》2016,11(4)
BackgroundRecent data suggest that the presence of associated metabolic abnormalities may be important modifiers of the association of obesity with a poorer prognosis in coronary heart disease. We determined the influence of isolated overweight and obesity on carotid intima media thickness (IMT-CC), and also assessed whether this influence was determined by the presence of metabolic abnormalities.Methods1002 participants from the CordioPrev study were studied at entry. We determined their metabolic phenotypes and performed carotid ultrasound assessment. We evaluated the influence of obesity, overweight and metabolic phenotypes on the IMT-CC.ResultsMetabolically sick participants (defined by the presence of two or more metabolic abnormalities) showed a greater IMT-CC than metabolically healthy individuals (p = 4 * 10−6). Overweight and normal weight patients who were metabolically healthy showed a lower IMT-CC than the metabolically abnormal groups (all p<0.05). When we evaluated only body weight (without considering metabolic phenotypes), overweight or obese patients did not differ significantly from normal-weight patients in their IMT-CC (p = 0.077). However, obesity was a determinant of IMT-CC when compared to the composite group of normal weight and overweight patients (all not obese).ConclusionsIn coronary patients, a metabolically abnormal phenotype is associated with a greater IMT-CC, and may be linked to a higher risk of suffering new cardiovascular events. The protection conferred in the IMT-CC by the absence of metabolic abnormality may be blunted by the presence of obesity.
Trial Registration
ClinicalTrials.gov NCT00924937相似文献897.
Laura Martin-Fernandez Andrey Ziyatdinov Marina Carrasco Juan Antonio Millon Angel Martinez-Perez Noelia Vilalta Helena Brunel Montserrat Font Anders Hamsten Juan Carlos Souto José Manuel Soria 《PloS one》2016,11(1)
Background
Venous thromboembolism (VTE) is a common disease where known genetic risk factors explain only a small portion of the genetic variance. Then, the analysis of intermediate phenotypes, such as thrombin generation assay, can be used to identify novel genetic risk factors that contribute to VTE.Objectives
To investigate the genetic basis of distinct quantitative phenotypes of thrombin generation and its relationship to the risk of VTE.Patients/Methods
Lag time, thrombin peak and endogenous thrombin potential (ETP) were measured in the families of the Genetic Analysis of Idiopathic Thrombophilia 2 (GAIT-2) Project. This sample consisted of 935 individuals in 35 extended families selected through a proband with idiopathic thrombophilia. We performed also genome wide association studies (GWAS) with thrombin generation phenotypes.Results
The results showed that 67% of the variation in the risk of VTE is attributable to genetic factors. The heritabilities of lag time, thrombin peak and ETP were 49%, 54% and 52%, respectively. More importantly, we demonstrated also the existence of positive genetic correlations between thrombin peak or ETP and the risk of VTE. Moreover, the major genetic determinant of thrombin generation was the F2 gene. However, other suggestive signals were observed.Conclusions
The thrombin generation phenotypes are strongly genetically determined. The thrombin peak and ETP are significantly genetically correlated with the risk of VTE. In addition, F2 was identified as a major determinant of thrombin generation. We reported suggestive signals that might increase our knowledge to explain the variability of this important phenotype. Validation and functional studies are required to confirm GWAS results. 相似文献898.
Meghan R. Mason Carolina Encina Srinand Sreevatsan Claudia Mu?oz-Zanzi 《PLoS neglected tropical diseases》2016,10(8)
BackgroundLeptospirosis is a neglected zoonosis affecting animals and humans caused by infection with Leptospira. The bacteria can survive outside of hosts for long periods of time in soil and water. While identification of Leptospira species from human cases and animal reservoirs are increasingly reported, little is known about the diversity of pathogenic Leptospira species in the environment and how surveillance of the environment might be used for monitoring and controlling disease.ConclusionsThis study reports the presence of pathogenic Leptospira in the peri-domestic environment of households in three community types and the differences in Leptospira diversity at the community level. Systematic environmental surveillance of Leptospira can be used for detecting changes in pathogen diversity and to identify and monitor contaminated areas where an increased risk of human infection exists. 相似文献
899.
Effect of EGCG On Fe(III)‐induced conformational transition of silk fibroin,a model of protein related to neurodegenerative diseases 下载免费PDF全文
The abnormal aggregation of amyloid proteins is reported to play a critical role in the etiology of neurodegenerative disorders. Studies have shown that excessive ferric irons are associated with the misfolding of amyloid proteins, and that (‐)‐epigallocatechin gallate (EGCG) is a good metallic ion chelator with inhibitory effect on the aggregation of amyloid proteins. EGCG has been thus considered as a potential drug candidate for the treatment of neurodegenerative diseases. However, the mechanism of action for EGCG in inhibition of aggregation of amyloid proteins is still remaining unclear. Silk fibroin (SF) shares similarities with amyloid proteins in some amino acid sequences and fibrillation kinetics. In this work, therefore, we used SF as a model of protein to investigate the effects of Fe(III) and EGCG on conformational transition by using turbidity assay, thioflavin T (ThT) fluorescence spectroscopy, Raman spectroscopy, and atomic force microscope (AFM). We demonstrated that low concentration of Fe(III) ions promoted the formation of β‐sheet conformers, while high concentration of Fe(III) ions inhibited further aggregation of SF. EGCG could significantly inhibit the conformational transition of SF when induced by Fe(III), and decrease the amount of β‐sheet conformers dose‐dependently. The findings provide important information regarding to EGCG as a potential agent for the prevention and treatment of neurodegenerative diseases. Fe(III) can accelerate the conformation transition of silk fibrion (SF) from random coil into β‐sheet, while (‐)‐epigallocatechin gallate (EGCG) inhibits Fe(III)‐induced β‐sheet aggregation of SF., 2016. © 2015 Wiley Periodicals, Inc. Biopolymers 105: 100–107, 2016 相似文献
900.