1,795 research outputs found

    The introduction of mandatory inter-municipal cooperation in small municipalities: preliminary lessons from Italy

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    PurposeThis article studies effects of mandatory inter-municipal cooperation (IMC) in small Italian municipalities. Data from 280 small Italian municipalities on effects of IMC in terms of higher efficiency, better effectiveness of local public services, and greater institutional legitimacy of the small municipalities participating in IMC have been investigated against four variables: size; geographical area; type of inter-municipal integration and IMC membership (the presence in the IMC of a bigger municipality, the so-called big brother).Design/methodology/approachData were gathered from a mail survey that was sent to a random sample of 1,360 chief financial officers acting in municipalities of under 5,000 inhabitants, stratified by size (0–1,000 and 1,001–5,000) and geographic area (North, Center, and South) criteria. To analyze dependency relationships between the three potential effects of participating in IMC and possible explanatory variables, we used a logistic regression model as the benefits were binarily categorized (presence or absence of benefits).FindingsFindings show that in more than two-thirds of the municipalities participating in IMC there were benefits in terms of costs reduction and better public services, whereas greater institutional legitimacy was detected in about half of the cases. Our statistical analysis with logistic regression highlighted that IMC type is particularly critical for explaining successful IMC. In particular, positive effects of IMC were mainly detected in those small municipalities that promoted a service delivery organization rather than participating in service delivery agreements or opting for mixed arrangements of joint public services delivery.Originality/valueThe paper focuses on small municipalities where studies are usually scant. Our analysis highlighted that the organizational setting is particularly critical for explaining successful IMC

    Permittivity and permeability of epoxy-magnetite powder composites at microwave frequencies

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    Radio, millimetre and sub-millimetre astronomy experiments as well as remote sensing applications often require castable absorbers with well known electromagnetic properties to design and realize calibration targets. In this context, we fabricated and characterized two samples using different ratios of two easily commercially available materials: epoxy (Stycast 2850FT) and magnetite (Fe3O4\mathrm{Fe_{3}O_{4}}) powder. We performed transmission and reflection measurements from 7 GHz up to 170 GHz with a VNA equipped with a series of standard horn antennas. Using an empirical model we analysed the data to extract complex permittivity and permeability from transmission data; then we used reflection data to validate the results. In this paper we present the sample fabrication procedure, analysis method, parameter extraction pipeline, and results for two samples with different epoxy-powder mass ratios.Comment: 7 pages, 18 figures, submitted to the Journal of Applied Physics (AIP

    Predicting the spatio-temporal dynamics of Popillia japonica populations

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    We developed a reaction–diffusion model to describe the spatio-temporal dynamics of the Japanese beetle (Popillia japonica Newman), based on adult abundance data collected by the Regional Phytosanitary Service during the monitoring activities in the infested area in Lombardy (northern Italy), from 2015 to 2021. The model simulated the abundance of the pest, with a discrete time step of one year along linear trajectories departing from an initial point of establishment. The model allowed the determination of the rate of expansion (i.e. the speed at which the leading edge of a population wave moves over time) of the pest along 13 different trajectories, ranging from 4.5 to 13.8 km/y, with a mean value of 8.2 km/y. Finally, we developed a land suitability index that summarises the effect of land use on the trajectory-specific rate of expansion of P. japonica. Specifically, the model revealed an increase in the rate of expansion of 260 m per year for each additional percentage point in the land suitability index. The model presented and the knowledge acquired in this work represent an important step forward in the comprehension of P. japonica population dynamics, and they represent important elements for the development of a decision support tool for pest risk managers to design and implement scientifically driven management actions

    Dispersal of Philaenus spumarius (Hemiptera: Aphrophoridae), a Vector of Xylella fastidiosa, in Olive Grove and Meadow Agroecosystems

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    The introduction of the Xylella fastidiosa Wells bacterium into Apulia (South Italy) has caused the massive dieback of olive trees, and is threatening olive production throughout the Mediterranean Region. The key vector of X. fastidiosa in Europe is the spittlebug Philaenus spumarius L. The dispersal capabilities of P. spumarius are poorly known, despite being a key parameter for the prediction of the spread of the bacterium. In this study, we have examined the dispersal of P. spumarius adults in two different agroecosystems in Italy: an olive grove in Apulia (Southern Italy) and a meadow in Piedmont (Northern Italy). Insects were marked with albumin and released during seven independent trials over 2 yr. The recapture data were pooled separately for each agroecosystem and used to estimate the dispersal kernels of P. spumarius in the olive grove and in the meadow. The diffusion coefficient estimate for P. spumarius was higher in the meadow than in the olive grove. The median distance from the release point for 1 d of dispersal was 26 m in the olive grove and 35 m in the meadow. On the basis of our model, we estimated that 50% of the spittlebug population remained within 200 m (98% within 400 m) during the 2 mo period of high abundance of the vector on olives in Apulia. The dispersal of P. spumarius is thus limited to some hundreds of meters throughout the whole year, although it can be influenced to a great extent by the structure of the agroecosystem

    Spittlebugs of Mediterranean Olive Groves: Host-Plant Exploitation throughout the Year

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    Spittlebugs are the vectors of the bacterium Xylella fastidiosa Wells in Europe, the causal agent of olive dieback epidemic in Apulia, Italy. Selection and distribution of dierent spittlebug species on host-plants were investigated during field surveys in 2016–2018 in four olive orchards of Apulia and Liguria Regions of Italy. The nymphal population in the herbaceous cover was estimated using quadrat samplings. Adults were collected by sweeping net on three dierent vegetational components: herbaceous cover, olive canopy, and wild woody plants. Three species of spittlebugs were collected: Philaenus spumarius L., Neophilaenus campestris (Fallén), and Aphrophora alni (L.) (Hemiptera: Aphrophoridae). Philaenus spumarius was the predominant species both in Apulia and Liguria olive groves. Nymphal stages are highly polyphagous, selecting preferentially Asteraceae Fabaceae plant families, in particular some genera, e.g., Picris, Crepis, Sonchus, Bellis, Cichorium, and Medicago. Host-plant preference of nymphs varies according to the Region and through time and nymphal instar. In the monitored sites, adults peak on olive trees earlier in Apulia (i.e., during inflorescence emergence) than in Liguria (i.e., during flowering and beginning of fruit development). Principal alternative woody hosts are Quercus spp. and Pistacia spp. Knowledge concerning plant selection and ecological traits of spittlebugs in dierent Mediterranean olive production areas is needed to design eective and precise control strategies against X. fastidiosa vectors in olive groves, such as ground cover modifications to reduce populations of spittlebug vectors

    Phenology, seasonal abundance and stage-structure of spittlebug (Hemiptera: Aphrophoridae) populations in olive groves in Italy

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    Spittlebugs (Hemiptera: Aphrophoridae) are the dominant xylem-sap feeders in the Mediterranean area and the only proven vectors of Xylella fastidiosa ST53, the causal agent of the olive dieback epidemic in Apulia, Italy. We have investigated the structured population phenology, abundance and seasonal movement between crops and wild plant species of both the nymphal and adult stages of different spittlebug species in olive groves. Field surveys were conducted during the 2016–2018 period in four olive orchards located in coastal and inland areas in the Apulia and Liguria regions in Italy. The nymphal population in the herbaceous cover was estimated using quadrat samplings. Adults were collected through sweep nets on three different vegetational components: herbaceous cover, olive canopy and wild woody plants. Philaenus spumarius was the most abundant species; its nymphs were collected from early March and reached a peak around mid-April, when the 4th instar was prevalent. Spittlebug adults were collected from late April until late autumn. P. spumarius adults were abundant on the herbaceous cover and olive trees in late spring, and they then dispersed to wild woody hosts during the summer and returned to the olive groves in autumn when searching for oviposition sites in the herbaceous cover. A relatively high abundance of P. spumarius was observed on olive trees during summer in the Liguria Region. The present work provides a large amount of data on the life cycle of spittlebugs within an olive agroecosystem that can be used to design effective control programmes against these vectors in infected areas and to assess the risk of the establishment and spread of X. fastidiosa to Xylella-free areas

    Simulazione della diapausa e della fenologia del coleottero Giapponese, Popillia japonica

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    Il coleottero giapponese (Popillia japonica Newman) è una specie polifaga e invasiva originaria del nord-est asiatico. Fin dalla sua prima individuazione negli Stati Uniti nel 1916, la specie è stata in grado di invadere vaste aree del nord America ed alcune aree del Canada meridionale. Negli anni '70, la P. japonica è stata introdotta nelle Azzorre e dal 2014 la specie si è insediata in Europa continentale (Italia). Dal 2017, in Svizzera sono stati segnalati alcuni avvistamenti della specie. In Italia, la P. japonica è distribuita lungo la Valle del Ticino al confine tra Lombardia e Piemonte e, dalla sua prima individuazione, l’area di infestazione è incrementata nel tempo. La specie è considerata un organismo da quarantena e quindi il Servizio Fitosanitario Nazionale Italiano e i due Servizi Fitosanitari Regionali stanno attuando misure volte al monitoraggio e al contenimento di P. japonica. Il controllo delle popolazioni di P. japonica può essere supportato dall’uso di modelli in grado di predire le tempistiche di emergenza degli stadi vitali suscettibili (ad esempio, larve e adulti). In questo lavoro, presentiamo un modello meccanicistico per simulare l’influenza della temperatura sull’inizio dei voli e sulla curva fenologica degli adulti di P. japonica. Il modello è stato calibrato e validato utilizzando serie temporali relative alla cattura di individui adulti tramite trappole a feromoni. I dati sono stati raccolti dal Servizio Fitosanitario della Regione Lombardia (Italia). Il modello è in grado di simulare realisticamente l’influenza della temperatura del suolo sui pattern di sviluppo e sulle strategie dei cicli di vita della specie. L’applicazione del modello a scala locale (ad esempio, simulazioni a livello puntuale) possono supportare i decisori (agricoltori, cooperative agricole ecc.) nella pianificazione e implementazione di azioni volte al monitoraggio e al controllo delle popolazioni basate sulle tempistiche di emergenza stimate dal modello. Il modello può essere inoltre applicato su scala regionale per ottenere mappe fenologiche che permettano di identificare le aree dove è prevista una emergenza anticipata della specie. Questa informazione può supportare i decisori che agiscono a livello regionale (ad esempio Servizi Fitosanitari Regionali) nella prioritizzazione delle aree di intervento, nell’implementazione di sistemi di allerta e nell’implementazione di piani di gestione della specie su scala regionale. Finanziamento: Il Progetto GESPO è Finanziato da “Direzione Generale Agricoltura - Regione Lombardia - D.d.s. 28 marzo 2018 - n. 4403D.g.r. n. X/7353 14 novembre 2017”

    Measurement of ISR-FSR interference in the processes e+ e- --> mu+ mu- gamma and e+ e- --> pi+ pi- gamma

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    Charge asymmetry in processes e+ e- --> mu+ mu- gamma and e+ e- --> pi+ pi- gamma is measured using 232 fb-1 of data collected with the BABAR detector at center-of-mass energies near 10.58 GeV. An observable is introduced and shown to be very robust against detector asymmetries while keeping a large sensitivity to the physical charge asymmetry that results from the interference between initial and final state radiation. The asymmetry is determined as afunction of the invariant mass of the final-state tracks from production threshold to a few GeV/c2. It is compared to the expectation from QED for e+ e- --> mu+ mu- gamma and from theoretical models for e+ e- --> pi+ pi- gamma. A clear interference pattern is observed in e+ e- --> pi+ pi- gamma, particularly in the vicinity of the f_2(1270) resonance. The inferred rate of lowest order FSR production is consistent with the QED expectation for e+ e- --> mu+ mu- gamma, and is negligibly small for e+ e- --> pi+ pi- gamma.Comment: 32 pages,29 figures, to be submitted to Phys. Rev.

    Report from Working Group 3: Beyond the standard model physics at the HL-LHC and HE-LHC

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    This is the third out of five chapters of the final report [1] of the Workshop on Physics at HL-LHC, and perspectives on HE-LHC [2]. It is devoted to the study of the potential, in the search for Beyond the Standard Model (BSM) physics, of the High Luminosity (HL) phase of the LHC, defined as 33 ab1^{-1} of data taken at a centre-of-mass energy of 14 TeV, and of a possible future upgrade, the High Energy (HE) LHC, defined as 1515 ab1^{-1} of data at a centre-of-mass energy of 27 TeV. We consider a large variety of new physics models, both in a simplified model fashion and in a more model-dependent one. A long list of contributions from the theory and experimental (ATLAS, CMS, LHCb) communities have been collected and merged together to give a complete, wide, and consistent view of future prospects for BSM physics at the considered colliders. On top of the usual standard candles, such as supersymmetric simplified models and resonances, considered for the evaluation of future collider potentials, this report contains results on dark matter and dark sectors, long lived particles, leptoquarks, sterile neutrinos, axion-like particles, heavy scalars, vector-like quarks, and more. Particular attention is placed, especially in the study of the HL-LHC prospects, to the detector upgrades, the assessment of the future systematic uncertainties, and new experimental techniques. The general conclusion is that the HL-LHC, on top of allowing to extend the present LHC mass and coupling reach by 2050%20-50\% on most new physics scenarios, will also be able to constrain, and potentially discover, new physics that is presently unconstrained. Moreover, compared to the HL-LHC, the reach in most observables will, generally more than double at the HE-LHC, which may represent a good candidate future facility for a final test of TeV-scale new physics

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis
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