7,026 research outputs found
2021 Home Grounds and Animals PMG - Author Contact List
No full textThis is a chapter of the 2021 Home Grounds and Animals PMG. This 2021 Virginia Pest Management Guide provides the latest recommendations for controlling diseases, insects, and weeds for home grounds and animals. This publication contains information about prevention and nonchemical control as alternatives to chemical control or as part of an integrated pest management approach. The chemical controls in this guide are based on the latest pesticide label information at the time of writing. Because pesticide labels change, read the label directions carefully before buying and using any pesticide. Regardless of the information provided here, always follow the latest product label instructions when using any pesticide. Commercial products are named in this publication for informational purposes only. Virginia Cooperative Extension does not endorse these products and does not intend discrimination against other products that also may be suitable.Peer reviewe
Advanced modeling for studying antineutrinos and gamma rays coming from the Earth
No full textIn questa tesi sono presentate le sfide scientifiche e i risultati dell'attività ricerca svolta durante il corso di dottorato a supporto della modellazione avanzata per l'analisi spaziale di dati di spettroscopia gamma e per la stima dei segnali di geoneutrini. Questi due argomenti, apparentemente distanti, sono in realtà strettamente connessi: in entrambi i casa la radioattività naturale rappresenta uno strumento per lo studio delle proprietà della superficie e dell'interno della Terra. In particolare ho trattato gli aspetti problematici relativi alla modellazione numerica e cartografica a differenti scale e ho proposto soluzioni operative riguardanti lo studio delle distribuzioni statistiche, il trattamento delle incertezze di input e output e la combinazione di informazioni multivariate. Questi studi mi hanno dato l'opportunità di prender parte al dibattito scientifico che cerca di rispondere alle domande ancora aperte sulla formazione e la composizione del nostro pianeta. I contenuti di questa tesi sono inclusi in 6 studi pubblicati, la cui realizzazione ha visto il coinvolgimento di circa 30 coautori, tra geologi e fisici, provenienti da diverse istituzioni di ricerca di rilevanza internazionale. In ogni capitolo uno specifico caso di studio è presentato e trattato da un particolare punto di vista in modo da mettere in luce il mio contributo. Lo studio degli elementi radiogenici e le previsioni sulla loro distribuzione sono elementi chiave per la comprensione dei processi geologici locali che interessano la crosta così come per lo studio della radioattività ambientale. La mappa della radioattività naturale terrestre della regione Veneto è stata ottenuta sulla base di un dataset integrato di spettroscopia gamma costituito da misure in laboratorio su campioni di roccia e misure airborne. In particolare ho integrato questi due differenti tipi di dati in un unico prodotto cartografico, usando algoritmi geostatistici adatti alle caratteristiche geologiche e morfologiche pecualiari delle aree investigate. I differenti contributi delle incertezze sono stati ampiamente discussi nel caso di studio nel Nord-Est della Sardegna. In questo lavoro la mappa di distribuzione dell'uranio è stata ottenuta sulla base di un dettagliato studio radiometrico realizzato con due differenti tecniche di spettroscopia gamma, caratterizzati da differenti errori di misura. Affrontando questa sfida, ho applicato un particolare metodo geostatistico che ha permesso di analizzare le incertezze di input e di output. Nel caso del rilievo gamma airborne dell'isola d'Elba, è stata usata un'interpolazione spaziale multivariata per ottenere le mappe radiometriche adottando la carta geologica come informazione a priori. In quest'ambito ho trattato gli aspetti complessi della correlazione di dati quantitativi (misure gamma) con le informazioni qualitative geologiche. La forte correlazione tra informazioni geologiche e contenuto di radioattività è stata enfatizzata nell'indagine approfondita condotta in una delle regioni più produttive di petrolio in Albania (Vlora-Elbasan) per la valutazione dei NORM (Naturally Occurring Radioactive Materials). Ho partecipato all'analisi delle misure di concentrazione di attività basata su argomentazioni geologiche e geochimiche. La caratterizzazione litologica delle aree petrolifere risulterà di importanza strategica per la pianificazione di future valutazioni radiologiche della regione. La combinazione dei risultati sperimentali dei segnali di geoneutrini da esperimenti in corso e futuri, può porre vincoli stringenti sul segnale atteso dal mantello e di conseguenza sulla sua composizione. In questa prospettiva una profonda conoscenza della crosta continentale, ed in particolare della regione immediatamente vicina al detector, è imprescindibile. In questo contesto, un dettagliato modello 3D derivante da informazioni geologiche, geofisiche e geochimiche è stato realizzato per stimare il flusso dei geoneutrini atteso al detector SNO+ (Canada). In particolare ho sviluppato un modello 3D strutturale della regione, trattando gli aspetti relativi alla complessità della modellazione del flusso di geoneutrini. Inoltre ho partecipato allo studio che ha portato alla prima stima del segnale dei geoneutrini atteso a JUNO, un rivelatore a scintillatore liquido attualmente in costruzione in Cina, insieme alla stima del segnale atteso degli antineutrini da reattore. La posizione dell'esperimento, molto vicina a due centrali nucleari progettate, riflette il principale goal scientifico di JUNO, ovvero lo studio della gerarchia di massa sulla base delle misure di antineutrini da reattore. In quest'ambito ho prodotto gli spettri dei geoneutrini e le relative incertezze fornendo un risultato che sarà un punto di riferimento e una guida per gli studi futuri. Questi studi riflettono l'interazione di tre discipline scientifiche fondamentali: la Fisica delle particelle, le Scienze della Terra e la Statistica. La loro interconnessione rivela un grande potenziale per il superamento delle frontiere della conoscenza. Ho trattato in prima persona i problemi specifici che nascono necessariamente quando differenti, ma non distanti, campi scientifici sono chiamati ad interagire.This thesis presents the scientific challenges and the goals of my research activity supporting the advanced modeling for the spatial analysis of gamma-ray data and for the predictions of geoneutrinos signal. These two topics, based on different measurements techniques and fields of view, are apparently distant but both make the natural radioactivity a probe for the study of the properties of Earth's surface and interior. I dealt the problematic aspects related to the numerical and cartographic modeling at different scales and I proposed operative solutions regarding mainly the study of statistical distributions, the treatment of the input and output uncertainties and the combination of multivariate information. These studies gave me the opportunity to take part in the scientific debate that tries to answer to the still open questions about the formation and composition of our planet. The contents of this thesis are included in 6 published works realized with the involvement of about 30 coauthors, geologists and physicists, from different istitutions in the world. In each chapter a specific case study is presented from a particular point of view shedding light on my contribution. The study of heat producing elements and the previsions of their distribution are key-points for the understanding of local geological processes affecting the crust as well as for the investigation of environmental radioactivity. The map of terrestrial natural radioactivity of the Veneto region (Italy) was obtained on the basis of an integrated gamma-ray dataset composed by laboratory measurements performed on rock samples and airborne measurements. I integrated these two different types of data in a unique cartographic product, using suitable geostatistical algorithms based on the distinctive geological and morphological features of the investigated areas. The different contributions of the uncertainties were widely faced in case study in the Northeastern Sardinia in which the uranium distribution map comes from a very refined radiometric investigation realized with two different γ-ray spectroscopy measurements methods, characterized by heterogeneous measurement errors. Taking on this challenge, I applied a particular geostatistical method that permitted to analyze the input and the output uncertainties. In the case of airborne gamma ray survey of Elba Island, a multivariate spatial interpolation was used for obtaining the radiometric maps using the geological map as a constraint. I dealt with the complex aspects of correlating quantitative data (γ-ray measurements) with the qualitative information of the geological map. The strong correlation between geological information and radioactivity content was emphasized in the extensive survey in one of the most important oil productive regions (Vlora-Elbasan) in Albania for the assessment of Naturally Occurring Radioactive Materials. I participated to the analysis of the activity concentrations measurements based on geological and geochemical arguments. The discrimination of the lithologic features of the oil fields and the test of geodynamic models can result strategic issues for the planning of the future radiological assessment of the region. Combining experimental results of geoneutrino signals at operating and future experiments, can place better constraints on the mantle signal and in turn on its composition. In this perspective a deep understanding of the continental crust, in particular the region immediately surrounding the detector, is mandatory. In this framework a detailed 3D model compiled from geological, geophysical, and geochemical information provided the estimation of the geoneutrino flux expected at the SNO+ detector (Canada). I developed the geophysical construction of a 3D structural model of the region, dealing with the related aspects to the complexity of the modeling the prediction of the geoneutrino flux. Moreover I performed the first estimation of the geoneutrino signal expected at JUNO, a liquid scintillation detector that will be built in China, together with a prediction of the expected reactor antineutrino signal. The experiment will be located very close to two planned nuclear plants in order to study the neutrino mass hierarchy, which is the last missing ingredient in the neutrino puzzle. I produced the geoneutrino spectra and the relative uncertainties providing a result that will be a reference point and a guide for future refinements. These studies reflect the melting of three fundamental scientific disciplines: Particle physics, Earth science and Statistics. Their interconnection reveals a great potential for advancing the frontiers of knowledge. I had to deal with specific problems that necessarily emerge when different, but not distant, fields of science are called to interact
GOCE Bayesian Gravity Inversion for Geoneutrino Exploitation at JUNO
No full textThe goal of this work is to build a 3D geophysical model of the 6° × 4° area centred at the location of the JUNO experiment, currently under construction in the Guangdong Province (South China), by exploiting GOCE gravity data integrated with some a-priori geological and geophysical knowledge by means of a Bayesian approach to gravity inversio
Author Checklist
No full textProvides a checklist to review manuscripts, for content, format, structure of tables, graphs and figures, text citations and references, and other concerns
National bestselling author Barbara Kingsolver to present on local dining at Virginia Tech
No full textAuthor Barbara Kingsolver will visit campus Tuesday, Sept. 14 to present her recent bestseller and this year's Virginia Tech Common Book about eating local food: Animal, Vegetable, Miracle.</p
Award-winning poet and author Jeff Mann to read from his works at Virginia Tech
No full textAward-winning poet and author Jeff Mann of the Virginia Tech Department of English will be reading from his works at the Volume II bookstore on April 8 at 7: p.m
2021 Horticultural and Forest PMG - Authors
No full textHorticultural and Forest Crops 2021 Author Contact ListPeer reviewe
Draft notes on the Seminole Trail (U.S. 29) in Virginia.
No full textNotes on the attempt by the author to find documentation for the origin and validity of the designation of Route 29 in Virginia as the "Seminole Trail"
Investigating beef cattle prices for short time periods
No full textAuthor attempts to add to the knowledge of beef cattle prices. Additional price knowledge should lead to more efficient resource use by those in the beef cattle industryResearch Division Repor
A fully automated gamma-ray spectrometer for NORMs characterization
No full textThe large production of naturally-occurring radioactive material (NORM) represent a severe radiological hazard for health and for this reason has to be subject to regulation. We designed, built-up and tested an ad-hoc laboratory instrument, the MCA_Rad, dedicated to the quantification of the specific activity of 40K and several radioisotope of 238U and 232Th decay chains. MCA_Rad is a high-resolution gamma-ray spectrometer system made of two 60% relative efficiency coaxial p-type HPGe detectors, with an energy resolution of ~1.9 keV at 1332.5 keV (60Co). The detectors are lead and copper shielded for reaching a low background, positioned facing each other and cooled at
approximately -190 °C by electromechanical stirling cryocoolers. The instrument is equipped with an automatic sample changer, which allows managing independently the measurement of 24 samples without any human intervention. The material is contained in a small cylindrical polycarbonate box of 180 cm3 of useful volume and labeled by a barcode that uniquely entifies the sample. A dedicated software has been developed in order to
automatically manage the acquisition and the spectral analysis: sum of the spectra, background subtraction, energy calibration and abundances estimation. The fully energy calibration of the detectors of the MCA_Rad was performed using certified reference materials of natural origin. The chemical composition and density were consered in order
to account for different photon attenuation within the source material itself. In our approach the correction factor for self-absorption effect was determined via Monte Carlo simulation. The overall uncertainty about the absolute efficiency of the MCA_Rad system is estimated to be <5 %. The MCA_Rad allows for checking the secular equilibrium among the U and Th decay chains segments. This makes this instrument particularly suitable for the
characterization of the NORMs which are, respect to a typical rock or soil sample, more subject to several chemical and physical processes that disturb the secular equilibrium. Moreover the overall uncertainty about the absolute efficiency of estimated to be <5 % and the full automation of the experimental setup, represent adding values for the accurate and of the systematic characterization of a large number of samples and in turn for the regulation
of the NORMs
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