From mobile phone data to the spatial structure of cities

Pervasive infrastructures, such as cell phone networks, enable to capture large amounts of human behavioral data but also provide information about the structure of cities and their dynamical properties. In this article, we focus on these last aspects by studying phone data recorded during 55 days in 31 Spanish metropolitan areas. We first define an urban dilatation index which measures how the average distance between individuals evolves during the day, allowing us to highlight different types of city structure. We then focus on hotspots, the most crowded places in the city. We propose a parameter free method to detect them and to test the robustness of our results. The number of these hotspots scales sublinearly with the population size, a result in agreement with previous theoretical arguments and measures on employment datasets. We study the lifetime of these hotspots and show in particular that the hierarchy of permanent ones, which constitute the "heart" of the city, is very stable whatever the size of the city. The spatial structure of these hotspots is also of interest and allows us to distinguish different categories of cities, from monocentric and "segregated" where the spatial distribution is very dependent on land use, to polycentric where the spatial mixing between land uses is much more important. These results point towards the possibility of a new, quantitative classification of cities using high resolution spatio-temporal data.Comment: 14 pages, 15 figure

Uncovering the spatial structure of mobility networks

The extraction of a clear and simple footprint of the structure of large, weighted and directed networks is a general problem that has many applications. An important example is given by origin-destination matrices which contain the complete information on commuting flows, but are difficult to analyze and compare. We propose here a versatile method which extracts a coarse-grained signature of mobility networks, under the form of a $2\times 2$ matrix that separates the flows into four categories. We apply this method to origin-destination matrices extracted from mobile phone data recorded in thirty-one Spanish cities. We show that these cities essentially differ by their proportion of two types of flows: integrated (between residential and employment hotspots) and random flows, whose importance increases with city size. Finally the method allows to determine categories of networks, and in the mobility case to classify cities according to their commuting structure.Comment: 10 pages, 5 figures +Supplementary informatio

Crystallization and preliminary X-ray diffraction analysis of levansucrase (LsdA) from Gluconacetobacter diazotrophicus SRT4

The endophytic bacterium Gluconacetobacter diazotrophicus SRT4 secretes a constitutively expressed levansucrase (LsdA; EC 2.4.1.10), which converts sucrose to fructo-oligosaccharides and levan. Fully active LsdA was purified to high homogeneity by non-denaturing reversed-phase HPLC and was crystallized at room temperature by the hanging-drop vapour-diffusion method using ammonium sulfate and ethanol as precipitants. The crystals are extremely sensitive, but native data have been collected to 2.5 A under cryogenic conditions using synchrotron radiation. LsdA crystals belong to the orthorhombic space group P22(1)2(1) or P2(1)2(1)2, with unit-cell parameters a = 53.80, b = 119.39, c = 215.10 A

Tracing out the Northern Tidal Stream of the Sagittarius Dwarf Spheoridal Galaxy

The main aim of this paper is to report two new detections of tidal debris in the northern stream of the Sagittarius dwarf galaxy located at 45 arcdeg and 55 arcdeg from the center of galaxy. Our observational approach is based on deep color-magnitude diagrams, that provides accurate distances, surface brightness and the properties of stellar population of the studied region of this tidal stream. The derived distances for these tidal debris wraps are 45 kpc and 54 kpc respectively.We also confirm these detections with numerical simulations of the Sagittarius dwarf plus the Milky Way. The model reproduces the present position and velocity of the Sagittarius main body and presents a long tidal stream formed by tidal interaction with the Milky Way potential. This model is also in good agreement with the available observations of the Sagittarius tidal stream. We also present a method for estimating the shape of the Milky Way halo potential using numerical simulations. From our simulations we obtain an oblateness of the Milky Way dark halo potential of 0.85, using the current database of distances and radial velocities of the Sagittarius tidal stream. The color-magnitude diagram of the apocenter of Sagittarius shows that this region of the stream shares the complex star formation history observed in the main body of the galaxy. We present the first evidence for a gradient in the stellar population along the stream, possibly correlated with its different pericenter passages. (abridged)Comment: 43 pages (including 15 figures; for high resolution color figures, please contact [email protected]). Submitted to Ap

Weather-based models for predicting grape powdery mildew (Uncinula necator (Schwein) Burrill) epidemics

El oídio de la vid (Vitis vinifera L.), causado por Uncinula necator (Schwein) Burrill, es una enfermedad fúngica relevante en viñedos de la provincia de Mendoza, ocasionando pérdidas de producción y degradación de la calidad del fruto cosechado. Durante seis campañas agrícolas (2001/02; 2002/03; 2005/06; 2007/08; 2008/09; 2009/10), en un parral del cultivar susceptible Chenín (EEA INTA Mendoza, Luján de Cuyo), se observó la evolución de la incidencia del oídio en racimos (como tasa de incremento epidémica diaria), desde floración hasta envero. A partir de registros térmico-hídricos horarios (monitoreados con sensores ubicados en la parte superior del canopeo) se calcularon variables meteorológicas en los 15 días previos a cada observación del progreso de la epidemia. Con variables que integran efectos de la temperatura, humedad del aire y frecuencia de precipitaciones ligeras sobre el incremento de la enfermedad en función del tiempo, se ajustaron modelos de regresión logística para estimar las probabilidades de ocurrencia de tasas epidémicas categorizadas (severa, moderada y nula), logrando una precisión de predicción máxima de 92,5% (modelo bivariado, N=40). Las predicciones del modelo univariado (seleccionado por "Stepwise"; precisión de predicción: 87,5%) se validaron satisfactoriamente con la curva epidémica observada en 2000/2001. Los valores estimados por estos modelos podrían complementar a las observaciones epidémicas y emitir alarmas regionales que sustenten la toma de decisión de control químico.Powdery mildew, caused by Uncinula necator (Schwein) Burrill is one of the most damaging disease affecting grapevines (Vitis vinifera L.) in Mendoza and worldwide, reducing yield and fruit quality. Throughout six growing seasons (2001/02; 2002/03; 2005/06; 2007/08; 2008/09; 2009/10), powdery mildew incidence values (expressed as daily epidemic increment rates) were observed in clusters from flowering to onset of ripening (change of color of the grape berries), in a grapevine planted with the susceptible Chenin cultivar at the EEA INTA Mendoza (Luján de Cuyo). From hourly values of thermal-moisture elements recorded by upper canopy sensors, meteorological variables were calculated in the 15 previous days of each epidemic observation. Using variables which integrate the effects of air temperature and humidity and frequency of light precipitations over the epidemic progress, logistic models were adjusted for estimating the probability of occurrrence of severe, moderate and nil epidemic increment rates, reaching maximum prediction accuracy of 92.5% (two variable models, N=40). Predicted values by the univariate model (selected by Stepwise procedure; prediction accuracy: 87.5%) were validated with the epidemic curve observed during 2000/2001 growing season. These model predictions could complement epidemic observations, giving regional scale to warning systems for improving the decision making process regarding disease chemical control.Fil: Oriolani, Enrique J. A.. Instituto Nacional de Tecnología Agropecuaria (Argentina). Estación Experimental Agropecuaria Mendoza.Fil: Moschini, Ricardo C.. Instituto de Clima y Agua. CIRN. INTA Castelar.Fil: Salas, Sergio. Instituto Nacional de Tecnología Agropecuaria (Argentina). Estación Experimental Agropecuaria Mendoza.Fil: Martinez, Malvina I.. Instituto de Clima y Agua. CIRN. INTA Castelar.Fil: Banchero, Santiago. Instituto de Clima y Agua. CIRN. INTA Castelar

Evidence for Avian Intrathoracic Air Sacs in a New Predatory Dinosaur from Argentina

Background: Living birds possess a unique heterogeneous pulmonary system composed of a rigid, dorsally-anchored lung and several compliant air sacs that operate as bellows, driving inspired air through the lung. Evidence from the fossil record for the origin and evolution of this system is extremely limited, because lungs do not fossilize and because the bellow-like air sacs in living birds only rarely penetrate (pneumatize) skeletal bone and thus leave a record of their presence.Methodology/Principal Findings: We describe a new predatory dinosaur from Upper Cretaceous rocks in Argentina, Aerosteon riocoloradensis gen. et sp. nov., that exhibits extreme pneumatization of skeletal bone, including pneumatic hollowing of the furcula and ilium. In living birds, these two bones are pneumatized by diverticulae of air sacs (clavicular, abdominal) that are involved in pulmonary ventilation. We also describe several pneumatized gastralia (“stomach ribs”), which suggest that diverticulae of the air sac system were present in surface tissues of the thorax.Conclusions/Significance: We present a four-phase model for the evolution of avian air sacs and costosternal-driven lung ventilation based on the known fossil record of theropod dinosaurs and osteological correlates in extant birds:(1) Phase I—Elaboration of paraxial cervical air sacs in basal theropods no later than the earliest Late Triassic.(2) Phase II—Differentiation of avian ventilatory air sacs, including both cranial (clavicular air sac) and caudal (abdominal air sac) divisions, in basal tetanurans during the Jurassic. A heterogeneous respiratory tract with compliant air sacs, in turn, suggests the presence of rigid, dorsally attached lungs with flow-through ventilation.(3) Phase III—Evolution of a primitive costosternal pump in maniraptoriform theropods before the close of the Jurassic.(4) Phase IV—Evolution of an advanced costosternal pump in maniraptoran theropods before the close of the Jurassic.In addition, we conclude:(5) The advent of avian unidirectional lung ventilation is not possible to pinpoint, as osteological correlates have yet to be identified for uni- or bidirectional lung ventilation.(6) The origin and evolution of avian air sacs may have been driven by one or more of the following three factors: flow-through lung ventilation, locomotory balance, and/or thermal regulation.</p

Telemedicina: Situação em Portugal

Introdução: A telemedicina é hoje reconhecida pela OMS como uma ferramenta para melhorar o acesso e a qualidade dos cuidados de saúde. Apesar das vantagens aparentes é uma tecnologia recente e está longe de constituir uma prática de rotina na vida clínica diária. Objectivo: Conhecer a situação actual em Portugal relativamente à telemedicina, nomeadamente: quais as Unidades de Saúde com instalações de telemedicina e áreas em que se desenvolve esta actividade; número de serviços anuais e evolução; dificuldades e obstáculos dos profissionais e Instituições; perspectivas futuras Metodologia: A recolha dos dados foi efectuado através de: inquérito enviados às ARS do Norte, Centro, Lisboa e Vale do Tejo, Alentejo, Algarve e IGIF; entrevista com algumas instituições relativa aos serviços em funcionamento; pesquisa bibliográfica e na Internet Resultados: Dos 6 inquéritos enviados foram recebidos 5, provenientes da ARS Norte, Centro, Lisboa e Vale do Tejo, Algarve e Alentejo. Foram efectuadas entrevistas: H S. João, CHVila Nova de Gaia, CHVale do Sousa e H Pediátrico de Coimbra. Obtivemos informações relativas aos equipamentos instalados e serviços actualmente em funcionamento, em todo o país, destacando- se o funcionamento nas áreas da cardiologia, imagiologia e dermatologia. Não havia registo do número de teleconsultas e transmissão de exames excepto no que se refere à ARS Alentejo. Das dificuldades e obstáculos encontrados salientamos a falta de adesão dos profissionais e instituições; custos do funcionamento do sistema; ausência de definição funcional dos profissionais envolvidos (falta de remuneração dos actos médicos e acumulação de funções); ausência de uma estratégia nacional. Quanto às perspectivas futuras, de um modo geral, os objectivos das ARS incluem: a ligação dos centros de saúde e hospitais, e petrechamento com um equipamento básico de Telemedicina em conformidade com as actividades e tipos de consulta a realizar; o desenvolvimento de projectos no âmbito do INTERREG III. Comentários: O desafio que as organizações tem que enfrentar é a mudança estrutural provocada pela modernização dos processos e métodos de trabalho, «o hospital virtual», e a diluição das barreiras entre os Cuidados Primários e os Diferenciados. A telemedicina exige novas formas de gestão e de medição de desempenho das instituições; esta actividade deve ser equiparada às outras normalmente desenvolvidas nas unidades de saúde. Introduction: Telemedicine is recognized by the WHO as a tool for improvement of access and the quality of health care. However it is not yet a routine procedure in health services. Objective: to assess the utilization of telemedicine in Portugal, namely: health care services equipped with telemedicine, and services provided; annual services and evolution; difficulties and obstacles from professionals and institutions; future trends Methodology: data was obtained through a questionnaire sent to the five Regional Administrations of Health and the Financial Department of Health, interviews with some of the professionals practising Telemedicine and research in the web Results: We received five questionnaires from the Regional Administrations of Health, and collected data from the following Hospitals: S. João, Vila Nova de Gaia, Vale do Sousa e Coimbra Children’s Hospital. We obtained information of the institutions practising telemedicine, and the type of services. Cardiology, radiology and dermatology were the services more frequently provided. The number of teleconsultations or transmitted studies was not registered, except in Alentejo. The more common difficulties to implement this technology were: clinical and providers acceptance; lack of integration into the health care mainstream (the costs of teleconsultations are not reimbursed); equipment and operational costs; absence of a national strategy. Future trends include the equipment of telemedicine stations in Primary and Hospital care and the development of projects in cooperation with Spain (INTERREG III). Comments: Organizations face the challenge of a structural change due to the new technologies (telemedicine and health informatics) and the disappearance of barriers between primary and hospital care. Institutional, organizational and national policies must face new realities to introduce telemedicine into the mainstream of health, including assessment of health outcomes

Telemedicina: Situação em Portugal

Introdução: A telemedicina é hoje reconhecida pela OMS como uma ferramenta para melhorar o acesso e a qualidade dos cuidados de saúde. Apesar das vantagens aparentes é uma tecnologia recente e está longe de constituir uma prática de rotina na vida clínica diária. Objectivo: Conhecer a situação actual em Portugal relativamente à telemedicina, nomeadamente: quais as Unidades de Saúde com instalações de telemedicina e áreas em que se desenvolve esta actividade; número de serviços anuais e evolução; dificuldades e obstáculos dos profissionais e Instituições; perspectivas futuras Metodologia: A recolha dos dados foi efectuado através de: inquérito enviados às ARS do Norte, Centro, Lisboa e Vale do Tejo, Alentejo, Algarve e IGIF; entrevista com algumas instituições relativa aos serviços em funcionamento; pesquisa bibliográfica e na Internet Resultados: Dos 6 inquéritos enviados foram recebidos 5, provenientes da ARS Norte, Centro, Lisboa e Vale do Tejo, Algarve e Alentejo. Foram efectuadas entrevistas: H S. João, CHVila Nova de Gaia, CHVale do Sousa e H Pediátrico de Coimbra. Obtivemos informações relativas aos equipamentos instalados e serviços actualmente em funcionamento, em todo o país, destacando- se o funcionamento nas áreas da cardiologia, imagiologia e dermatologia. Não havia registo do número de teleconsultas e transmissão de exames excepto no que se refere à ARS Alentejo. Das dificuldades e obstáculos encontrados salientamos a falta de adesão dos profissionais e instituições; custos do funcionamento do sistema; ausência de definição funcional dos profissionais envolvidos (falta de remuneração dos actos médicos e acumulação de funções); ausência de uma estratégia nacional. Quanto às perspectivas futuras, de um modo geral, os objectivos das ARS incluem: a ligação dos centros de saúde e hospitais, e petrechamento com um equipamento básico de Telemedicina em conformidade com as actividades e tipos de consulta a realizar; o desenvolvimento de projectos no âmbito do INTERREG III. Comentários: O desafio que as organizações tem que enfrentar é a mudança estrutural provocada pela modernização dos processos e métodos de trabalho, «o hospital virtual», e a diluição das barreiras entre os Cuidados Primários e os Diferenciados. A telemedicina exige novas formas de gestão e de medição de desempenho das instituições; esta actividade deve ser equiparada às outras normalmente desenvolvidas nas unidades de saúde. Introduction: Telemedicine is recognized by the WHO as a tool for improvement of access and the quality of health care. However it is not yet a routine procedure in health services. Objective: to assess the utilization of telemedicine in Portugal, namely: health care services equipped with telemedicine, and services provided; annual services and evolution; difficulties and obstacles from professionals and institutions; future trends Methodology: data was obtained through a questionnaire sent to the five Regional Administrations of Health and the Financial Department of Health, interviews with some of the professionals practising Telemedicine and research in the web Results: We received five questionnaires from the Regional Administrations of Health, and collected data from the following Hospitals: S. João, Vila Nova de Gaia, Vale do Sousa e Coimbra Children’s Hospital. We obtained information of the institutions practising telemedicine, and the type of services. Cardiology, radiology and dermatology were the services more frequently provided. The number of teleconsultations or transmitted studies was not registered, except in Alentejo. The more common difficulties to implement this technology were: clinical and providers acceptance; lack of integration into the health care mainstream (the costs of teleconsultations are not reimbursed); equipment and operational costs; absence of a national strategy. Future trends include the equipment of telemedicine stations in Primary and Hospital care and the development of projects in cooperation with Spain (INTERREG III). Comments: Organizations face the challenge of a structural change due to the new technologies (telemedicine and health informatics) and the disappearance of barriers between primary and hospital care. Institutional, organizational and national policies must face new realities to introduce telemedicine into the mainstream of health, including assessment of health outcomes

Matrix metalloproteinase-10 is upregulated by thrombin in endothelial cells and increased in patients with enhanced thrombin generation

OBJECTIVE: Thrombin is a multifunctional serine protease that promotes vascular proinflammatory responses whose effect on endothelial MMP-10 expression has not previously been evaluated. METHODS AND RESULTS: Thrombin induced endothelial MMP-10 mRNA and protein levels, through a protease-activated receptor-1 (PAR-1)-dependent mechanism, in a dose- and time-dependent manner. This effect was mimicked by a PAR-1 agonist peptide (TRAP-1) and antagonized by an anti-PAR-1 blocking antibody. MMP-10 induction was dependent on extracellular regulated kinase1/2 (ERK1/2) and c-jun N-terminal kinase (JNK) pathways. By serial deletion analysis, site-directed mutagenesis and electrophoretic mobility shift assay an AP-1 site in the proximal region of MMP-10 promoter was found to be critical for thrombin-induced MMP-10 transcriptional activity. Thrombin and TRAP-1 upregulated MMP-10 in murine endothelial cells in culture and in vivo in mouse aorta. This effect of thrombin was not observed in PAR-1-deficient mice. Interestingly, circulating MMP-10 levels (P<0.01) were augmented in patients with endothelial activation associated with high (disseminated intravascular coagulation) and moderate (previous acute myocardial infarction) systemic thrombin generation. CONCLUSIONS: Thrombin induces MMP-10 through a PAR-1-dependent mechanism mediated by ERK1/2, JNK, and AP-1 activation. Endothelial MMP-10 upregulation could be regarded as a new proinflammatory effect of thrombin whose pathological consequences in thrombin-related disorders and plaque stability deserve further investigation