128 research outputs found

    Does urban sprawl increase the costs of providing local public services? Evidence from Spanish municipalities

    Get PDF
    This paper examines the impact of urban sprawl, a phenomenon of particular interest in Spain, which is currently experiencing this process of rapid, low-density urban expansion. Many adverse consequences are attributed to urban sprawl (e.g., traffic congestion, air pollution and social segregation), though here we are concerned primarily with the rising costs of providing local public services. Our initial aim is to develop an accurate measure of urban sprawl so that we might empirically test its impact on municipal budgets. Then, we undertake an empirical analysis using a cross-sectional data set of 2,500 Spanish municipalities for the year 2003 and a piecewise linear function to account for the potentially nonlinear relationship between sprawl and local costs. The estimations derived from the expenditure equations for both aggregate and six disaggregated spending categories indicate that low-density development patterns lead to greater provision costs of local public services.En el presente trabajo se analiza el impacto de la dispersión urbana, un fenómeno de especial interés en España, donde destaca la rapidez con la que este proceso de desarrollo urbano de baja densidad esta teniendo lugar actualmente. A pesar de la diversidad de consecuencias atribuidas a la dispersión urbana (tales como congestión del tráfico, contaminación o segregación social), aquí nos centramos en analizar el incremento en el coste de provisión de los servicios públicos locales. Con este objetivo, en primer lugar definimos una medida precisa de dispersión urbana que nos permita analizar empíricamente su impacto sobre los presupuestos municipales. En segundo lugar, llevamos a cabo un análisis empírico con datos de corte transversal para 2.500 municipios españoles referidos al año 2003 y una función lineal por tramos que recoge la posible relación no lineal existente entre la dispersión urbana y los costes. Las estimaciones obtenidas para las ecuaciones de gasto tanto a nivel agregado como para las seis categorías de gasto consideradas muestran que los desarrollos urbanos de baja densidad incrementan el coste de provisión de los servicios públicos locales

    En el espejo de la Esfinge Gran Bretaña y Egipto sentando las bases para la expansión capitalista estadounidense en el Caribe a inicios del siglo XX

    Get PDF
    Des de la Guerra Hispanoamericana a 1898 fins a més enllà de la fi de la primera Guerra Mundial, els Estats Units van emprendre una croada expansionista sense precedents en la història de el continent americà. La nova potència que disputava l’hegemonia global va ocupar militarment a Puerto Rico, Cuba, República Dominicana, Haití, Panamà, Nicaragua i Mèxic, aplanant el camí per a l’establiment dels seus bancs i empreses, els quals integrarien la regió a el creixement i desenvolupament del seu capital monopolista i financer. No obstant això, el mètode no va ser absolutament inèdit. Ja a la fi de el segle anterior els britànics havien establert les bases per al desplegament de tal dominació imperialista. És per això que, a l’igual que Giovanni Arrighi, va contextualitzar la meva lectura en el marc del llarg segle XX que va començar en els 1870 i que s’estén a través de la següent centúria. Per tant, en aquest article intent examinar com l’ocupació britànica d’Egipte el 1882 i l’argument del deute va marcar certes pautes que ens permeten entendre les dinàmiques que assumeix l’imperialisme nord-americà en la seva expansió a principis de segle XX al Carib.From the Spanish-American War in 1898 until beyond World War I, the United States undertook an expansionist crusade unprecedented in the history of the American continent. The new power that disputed global hegemony militarily occupied Puerto Rico, Cuba, Dominican Republic, Haiti, Panama, Nicaragua, and Mexico, paving the way for the establishment of its banks and companies, which would integrate the region to the growth and development of its monopoly- financial capital. However, the method was not novel. Already at the end of the previous century, the British had laid the foundations for the deployment of such imperialist domination. That is why, like Giovanni Arrighi, I contextualize my reading in the framework of The Long 20th Century that began in the 1870s and extends through the next century. Therefore, in this article, I try to examinehow the British occupation of Egypt in 1882 and the debt argument markedcertain guidelines that allow us to understand the dynamics assumed by US imperialism in its expansion in the early twentieth century in the Caribbean.Desde la Guerra Hispanoamericana en 1898 hasta más allá del final de la primera Guerra Mundial, los Estados Unidos emprendieron una cruzada expansionista sin precedentes en la historia del continente americano. La nueva potencia que disputaba la hegemonía global ocupó militarmente a Puerto Rico, Cuba, República Dominicana, Haití, Panamá, Nicaragua y México, allanando el camino para el establecimiento de sus bancos y empresas, los cuales integrarían la región al crecimiento y desarrollo de su capital monopolista-financiero. Sin embargo, el método no fue absolutamente inédito. Ya a finales del siglo anterior los británicoshabían sentado las bases para el despliegue de tal dominación imperialista. Es por eso que, al igual que Giovanni Arrighi, contextualizo mi lectura en el marco de El Largo siglo XX que comenzó en los 1870’s y que se extiende a través de la siguiente centuria. Por lo tanto, en este artículo intento examinar cómo la ocupación británica de Egipto en 1882 y el argumento de la deuda marcó ciertas pautas que nos permiten entender las dinámicas que asume el imperialismo estadounidense en su expansión a principios del siglo XX en el Caribe

    SOIL FERTILITY EVALUATION OF COFFEE (Coffea spp.) PRODUCTION SYSTEMS AND MANAGEMENT RECOMMENDATIONS FOR THE BARAHONA PROVINCE, DOMINICAN REPUBLIC

    Get PDF
    ABSTRACT Reported yields in most coffee farms of the Barahona province in the Dominican Republic are relatively low (< 290 kg ha -1 parchment coffee). In general, coffee producers do not use diagnostic techniques such as soil testing. This fact prevents them from identifying the limiting factors (especially nutrients), complicates the work of coffee cultural management practices, and potentially reduces productivity and coffee quality. This study was designed to diagnose the fertility level of soils in coffee farms in the area of Barahona in 96 farms within an area of 637 hectares and design a nutrient management strategy. Soils from each farm were sampled and analyzed for soil fertility parameters. A survey was provided to farmers that permitted the collection of information regarding yields, management practices, and landscape features. Soils in the area were predominantly clayey. Soil pH varied between 4.61 and 7.69 and soil organic matter ranged between 3.29 and 10.9%. Exchangeable potassium levels were classified as deficient in all areas. The clustering of results identified two main components, which accounted for 76% of the variability of the data and the grouping into five communities by similarity of features. The results show that soil testing of this coffee coffee-growing region can be used as a tool to diagnose the soil fertility status and guide them in implementing management and fertilization recommendations

    Fresh-cut carrot (cv. Nantes) quality as affected by abiotic stress (heat shock and UV-C irradiation) pre-treatments

    Get PDF
    Available at Sciverse ScienceDirectAbiotic stresses such as heat shock and UV-C irradiation can be used to induce synthesis of bioactive compounds and to prevent decay in fresh-cut fruits and vegetables. This study aimed to evaluate the effects of heat shock and UV-C radiation stress treatments, applied in whole carrots, on the overall quality of fresh-cut carrot cv. Nantes during storage (5 C). Heat shock (HS, 100 C/45 s) and UV-C (0.78 0.36 kJ/m2) treated samples had higher phenolic content and exhibited reduced POD activities during storage when compared to control (Ctr) samples (200 mg/L free chlorine/1 min). All samples showed reduced carotenoid content considering raw material. Nonetheless, UV samples registered a three-fold increase in carotenoid content in subsequent storage. Fresh-cut carrot colour showed a continuous increase in whiteness index (WI) values during storage regardless of treatment without impairing visual quality. Respiratory metabolism was affected by both abiotic stress treatments since reduced O2/CO2 rates were found, more significant in HS samples. The decontamination effect was more expressive in HS samples, where a 2.5 Log10 cfu/g reduction in initial microbial load and reduced microbial growth were achieve

    Patterns of nucleotide diversity at the regions encompassing the Drosophila insulin-like peptide (dilp) genes: demography vs positive selection in Drosophila melanogaster.

    Get PDF
    In Drosophila, the insulin-signaling pathway controls some life history traits, such as fertility and lifespan, and it is considered to be the main metabolic pathway involved in establishing adult body size. Several observations concerning variation in body size in the Drosophila genus are suggestive of its adaptive character. Genes encoding proteins in this pathway are, therefore, good candidates to have experienced adaptive changes and to reveal the footprint of positive selection. The Drosophila insulin-like peptides (DILPs) are the ligands that trigger the insulin-signaling cascade. In Drosophila melanogaster, there are several peptides that are structurally similar to the single mammalian insulin peptide. The footprint of recent adaptive changes on nucleotide variation can be unveiled through the analysis of polymorphism and divergence. With this aim, we have surveyed nucleotide sequence variation at the dilp1-7 genes in a natural population of D. melanogaster. The comparison of polymorphism in D. melanogaster and divergence from D. simulans at different functional classes of the dilp genes provided no evidence of adaptive protein evolution after the split of the D. melanogaster and D. simulans lineages. However, our survey of polymorphism at the dilp gene regions of D. melanogaster has provided some evidence for the action of positive selection at or near these genes. The regions encompassing the dilp1-4 genes and the dilp6 gene stand out as likely affected by recent adaptive events

    Multifrequency studies of the peculiar quasar 4C+21.35 during the 2010 flaring activity

    Get PDF
    The discovery of rapidly variable Very High Energy ( VHE; E &gt; 100 GeV). - ray emission from 4C + 21.35 ( PKS 1222+ 216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope ( LAT) in high energy ( HE; E &gt; 100 MeV). - rays, poses intriguing questions on the location of the. - ray emitting region in this flat spectrum radio quasar. We present multifrequency data of 4C + 21.35 collected from centimeter to VHE during 2010 to investigate the properties of this source and discuss a possible emission model. The first hint of detection at VHE was observed by MAGIC on 2010 May 3, soon after a gamma- ray flare detected by Fermi-LAT that peaked on April 29. The same emission mechanism may therefore be responsible for both the HE and VHE emission during the 2010 flaring episodes. Two optical peaks were detected on 2010 April 20 and June 30, close in time but not simultaneous with the two gamma- ray peaks, while no clear connection was observed between the X-ray and gamma- ray emission. An increasing flux density was observed in radio and mm bands from the beginning of 2009, in accordance with the increasing gamma- ray activity observed by Fermi-LAT, and peaking on 2011 January 27 in the mm regime ( 230 GHz). We model the spectral energy distributions ( SEDs) of 4C + 21.35 for the two periods of the VHE detection and a quiescent state, using a one-zone model with the emission coming from a very compact region outside the broad line region. The three SEDs can be fit with a combination of synchrotron self-Compton and external Compton emission of seed photons from a dust torus, changing only the electron distribution parameters between the epochs. The fit of the optical/UV part of the spectrum for 2010 April 29 seems to favor an inner disk radius of &lt; six gravitational radii, as one would expect from a prograde-rotating Kerr black hole.</p

    Potential of Core-Collapse Supernova Neutrino Detection at JUNO

    Get PDF
    JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

    Peri-operative red blood cell transfusion in neonates and infants: NEonate and Children audiT of Anaesthesia pRactice IN Europe: A prospective European multicentre observational study

    Get PDF
    BACKGROUND: Little is known about current clinical practice concerning peri-operative red blood cell transfusion in neonates and small infants. Guidelines suggest transfusions based on haemoglobin thresholds ranging from 8.5 to 12 g dl-1, distinguishing between children from birth to day 7 (week 1), from day 8 to day 14 (week 2) or from day 15 (≥week 3) onwards. OBJECTIVE: To observe peri-operative red blood cell transfusion practice according to guidelines in relation to patient outcome. DESIGN: A multicentre observational study. SETTING: The NEonate-Children sTudy of Anaesthesia pRactice IN Europe (NECTARINE) trial recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. PATIENTS: The data included 5609 patients undergoing 6542 procedures. Inclusion criteria was a peri-operative red blood cell transfusion. MAIN OUTCOME MEASURES: The primary endpoint was the haemoglobin level triggering a transfusion for neonates in week 1, week 2 and week 3. Secondary endpoints were transfusion volumes, 'delta haemoglobin' (preprocedure - transfusion-triggering) and 30-day and 90-day morbidity and mortality. RESULTS: Peri-operative red blood cell transfusions were recorded during 447 procedures (6.9%). The median haemoglobin levels triggering a transfusion were 9.6 [IQR 8.7 to 10.9] g dl-1 for neonates in week 1, 9.6 [7.7 to 10.4] g dl-1 in week 2 and 8.0 [7.3 to 9.0] g dl-1 in week 3. The median transfusion volume was 17.1 [11.1 to 26.4] ml kg-1 with a median delta haemoglobin of 1.8 [0.0 to 3.6] g dl-1. Thirty-day morbidity was 47.8% with an overall mortality of 11.3%. CONCLUSIONS: Results indicate lower transfusion-triggering haemoglobin thresholds in clinical practice than suggested by current guidelines. The high morbidity and mortality of this NECTARINE sub-cohort calls for investigative action and evidence-based guidelines addressing peri-operative red blood cell transfusions strategies. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02350348

    Detection of the Diffuse Supernova Neutrino Background with JUNO

    Get PDF
    As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

    Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

    Full text link
    Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30MM_{\odot} for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure
    corecore