Papers by Giovanni E. Gigante
Effect of extremely low frequency electromagnetic fields (ELF-EMF) on Kaposi's sarcoma-associated herpes virus in BCBL-1 cells
Bioelectromagnetics, 2006
Association between extremely low frequency electromagnetic fields (ELF-EMF) and human cancers is... more Association between extremely low frequency electromagnetic fields (ELF-EMF) and human cancers is controversial, and few studies have been conducted on their influence on oncogenic viruses. We studied the effects of 1 mT, 50 Hz sine waves, applied for 24-72 h, on Kaposi's sarcoma (KS)-associated herpesvirus (KSHV or HHV-8) in BCBL-1, a latently infected primary effusion lymphoma (PEL) cell line. ELF-EMF exposure did not affect the growth and viability of BCBL-1 cells, either stimulated or not with TPA. The total amount of KSHV DNA detected in ELF-EMF exposed cultures not stimulated with TPA did not differ from that of the unexposed controls (P = ns). However, in the presence of TPA stimulation, total KSHV DNA content was found higher in ELF-EMF exposed than in control BCBL-1 cultures (P = .024) at 72 h exposure, but not earlier. Viral DNA increase significantly correlated with increased mean fluorescence intensity/cell for the lytic antigen gp K8.1A/B (P < .01), but not with percentage of gp K8.1A/B-positive cells or of cells containing virions. Viral progeny produced under ELF-EMF exposure consisted mainly of defective viral particles.
Physical Review A, 1989
The spectrum from Compton-scattered x rays is an inherently broad distribution. This distribu- ti... more The spectrum from Compton-scattered x rays is an inherently broad distribution. This distribu- tion is the sum of several Gaussian-like distributions, which gives the sum its unique shape. The Gaussian-like distributions are the result of convoluting the so-called Compton profile, the spread in the scattered-x-ray energies due to the momentum distributions of the target electrons, with the detector response and the geometrical effects. The distribution is then further modified by the ab- sorption within the sample. A formulation for both qualitatively and quantitatively determining the magnitude of the geometrical contributions is presented. This formulation is based on a recently devised approach to the scattering geometry [Hanson, Gigante, Meron, Phys. Rev. Lett. 61, 135 (1988)]. A methodology for determining the geometrical spread in the energy of the scattered x rays is presented. The results can be conveniently used to optimize scattering geometries for the reduc- tion of the geometry-caused spread.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1989
A new approach to the evaluation of the conical collimator response function is shown. i h e bari... more A new approach to the evaluation of the conical collimator response function is shown. i h e barie collimator formulae are reviewed. The collimator response function has been found in a very easy way. An approximate soluiion has been introduced. Studying the response of a rneasuring systcm, the use of this approxirnation strongly reduces the eompiexity of the relations to be used; thcrefon it would pronde a useful starting point for a Monte Carlo calculation. The errorr introduced are less ihan 10%. Approximate relations that allow the evaluation of the response of conical and cylindrical collimators lo piane and line sourics arc also givm.
Journal of Physical and Chemical Reference Data, 2003
Bulletin of the American Schools of Oriental Research, 2004
Fresenius' Zeitschrift für analytische Chemie, 1987
Zusammenfassung. Die verschiedenen Anregungsmethoden der Rtntgenspektralanalyse mit Protonen, Pho... more Zusammenfassung. Die verschiedenen Anregungsmethoden der Rtntgenspektralanalyse mit Protonen, Photonen und Elektronen (PIXE, XRFA bzw. EPMA) werden hinsichtlich ihres Nachweisvermtgens, ihrer Pr/izision und Genauigkeit verglichen. Die Beurteilung der jeweils optimierten Anregungsmethoden basiert auf praktischen Problemen der Spurenanalyse: auf der Analyse von Aluminium, von Blei und yon Spurenkonzentraten aus Wasser und Glas. Fiir dicke homogene Proben erwies sich die XRFA wegen der sehr guten Stabilitfit der heutigen Ger/ite als iiberlegen. PIXE ist vorteilhaft anzuwenden, wenn dfinne Proben vorliegen oder wenn eine Probenvorbereitung, wie z.B. eine chemische Voranreicherung, erforderlich ist, die zu einer zus/itzlichen Streuung yon ~> 1% ffihrt, so dab die hohe Stabilitfit der XRFA-Ger/ite nicht mehr zum Tragen kommt. EPMA ist sowohl PIXE als auch XRFA unterlegen, solange nicht die lokale Verteilung von Elementen zu ermitteln ist.
X-Ray Scattering Cross Sections for Molecules, Plastics, Tissues, and Few Biological Materials
Journal of Trace and Microprobe Techniques, 2002
Compton and Rayleigh scattering cross sections for bone, bakelite, polycarbonate, nylon, lucite, ... more Compton and Rayleigh scattering cross sections for bone, bakelite, polycarbonate, nylon, lucite, polystyrene, polyethylene, water, glycogen, fat, calcium hydroxyapatite and protein are calculated for various monoenergetic Kα X-ray energies covering the angular region from 0 to 180° using non-relativistic, relativistic, relativistic modified and molecular form factors and the non-relativistic incoherent scattering function. The scattered radiation from these materials will be
Materials Science and Engineering: C, 2017
Synchrotron-based XRD spectra from rat bone of different age groups (w, 56 w and 78w), lumber ver... more Synchrotron-based XRD spectra from rat bone of different age groups (w, 56 w and 78w), lumber vertebra at early stages of bone formation, Calcium hydroxyapatite (HAp) [Ca 10 (PO 4) 6 (OH) 2 ] bone fill with varying composition (60% and 70%) and bone cream (35-48%), has been acquired with 15 keV synchrotron X-rays. Experiments were performed at Desy, Hamburg, Germany, utilizing the Resonant and Diffraction beamline (P9), with 15 keV X-rays (λ = 0.82666 A 0). Diffraction data were quantitatively analyzed using the Rietveld refinement approach, which allowed us to characterize the structure of these samples in their early stages. Hydroxyapatite, received considerable attention in medical and materials sciences, since these materials are the hard tissues, such as bone and teeth. Higher bioactivity of these samples gained reasonable interest for biological application and for bone tissue repair in oral surgery and orthopedics. The results obtained from these samples, such as phase data, crystalline size of the phases, as well as the degree of crystallinity, confirm the apatite family crystallizing in a hexagonal system, space group P6 3 /m with the lattice parameters of a = 9.4328 Å and c = 6.8842 Å (JCPDS card #09-0432). Synchrotron-based XRD patterns are relatively sharp and well resolved and can be attributed to the hexagonal crystal form of hydroxyapatite. All the samples were examined with scanning electron microscope at an accelerating voltage of 15 kV. The presence of large globules of different sizes is observed, in small age groups of the rat bone (8w) and lumber vertebra (LV), as distinguished from, large age groups (56 and 78w) in all samples with different magnification, reflects an amorphous phase without significant traces of crystalline phases. Scanning electron microscopy (SEM) was used to characterize the morphology and crystalline properties of Hap, for all the samples, from 2 to 100 μm resolution.
Fourier transform infrared spectroscopic characterization of complexes of carbamoylated quinidine chiral selector and N-derivatized leucine enantiomers in solution
Analytica Chimica Acta, 1999
ABSTRACT
Inexpensive ct-scanner using a photodiode array or an image intensifier
XRF technique application on diagnostics of wall paintings
Microcalcification Detection Using a Kernel Bayes Classifier
Medical Data Analysis, 2002
ABSTRACT Mammography associated with clinical breast examination is the only effective method for... more ABSTRACT Mammography associated with clinical breast examination is the only effective method for mass breast screening. Microcalcifications are one of the primary signs for early detection of breast cancer. In this paper we propose a new kernel method for classification of dificult to diagnose regions in mammographic images. It consists of a novel class of Markov Random Fields, using techniques developed within the context of statistical mechanics. This method is used for the classification of positive Region of Interest (ROI’s) containing clustered microcalcifications and negative ROI’s containing normal tissue. We benchmarked the new proposed method with a nearest neighbor classifier and with an artificial neural network, widely used in literature for computer-aided diagnosis. We obtained the best performance using the novel approach.
Nouvelles recherches sur les ors etrusques de la collection Castellani
Les recherches utilisant des methodes non destructives ont ete mises en oeuvre pour l'etude d... more Les recherches utilisant des methodes non destructives ont ete mises en oeuvre pour l'etude des ors de la collection Castellani conserves au Musee National Etrusque de Villa Guilia (Rome). L'analyse au microscope des bijoux, realisee pour identifier les anciennes techniques de fabrication et associee a l'examen de la composition des elements par ED-XRF a permis d'obtenir de nouvelles donnees en utilisant une methodologie multidisciplinaire basee sur la correlation avec les recherches d'ordre chronologique, typologique, stylistique et culturel
Dielectric Spectroscopy of Human Lymphocytes Exposed to a 3Hz Pulsed Magnetic field
The Metal, with an Appendix on Archaeometallurgical Studies
Cesare Brandi e il mondo della scienza e della tecnologia
Méthodologies de recherches pour la paléométallurgie: les metaux du site Villanovien du Gran Carro (Bolsena)
Les trouvailles metalliques provenant de l'habitat submerge de Gran Carro dans le lac de Bols... more Les trouvailles metalliques provenant de l'habitat submerge de Gran Carro dans le lac de Bolsena (Latium septentrional) sont particulierement interssantes par leur homogeneite chronologique et culturelle, cet habitat s'est developpe pendant la periode archaique au debut du premier Age du Fer. Pour mener a bien cette enquete on a choisi d'asssocier une etude preliminaire d'ordre chronologique et typologique des objets a un e definition de alliages metalliques obtenus par fluorescence X dispersive en enregie (ED-XRF) et a des analayses metallographiques realisees au moyen d'un microscope optique et electronique et combinees avec un e systeme de microanalyses computerisees. L'etude des objets a prouve, entre autres, l'existence d'une fonderie locale
XISMuS — X-ray fluorescence imaging software for multiple samples
SoftwareX, 2020
Abstract X-rays have long been used as a non-destructive analytical technique to investigate arte... more Abstract X-rays have long been used as a non-destructive analytical technique to investigate artefacts and objects that can be considered cultural heritage. With the unceasing development of technologies and miniaturization of electronics, X-ray Fluorescence (XRF) analysis has undergone a natural evolution, being now extensively used in a bi-dimensional manner, scanning whole surfaces and generating astonishing amounts of data. Evaluating all this data demands a software distribution or at least a stand-alone algorithm. The former being an obvious choice, as software are easy to install and the learning curve is fast. Moreover, developing a proprietary algorithm is time consuming and not always needed for the average user. In this scope, XIMuS was developed as an ad hoc software for macro-XRF analysis (MA-XRF), with an intuitive and simple graphical user interface (GUI). The software provides several built-in tools, staple for the interpretation of X-ray fluorescence data, automated data evaluation and some novelty functionalities as data stitching. XISMuS creates an iterative user database as samples are loaded and compiled through usage, facilitating navigation through different datasets. Simultaneous samples can be loaded in separate instances for comparison purposes. Elemental mapping is made simple, the methods available are described and have each one an application for fast, balanced or precise calculations, supporting parallel computing. Ratios between elements in specific regions of the image can be measured while a region-derived spectrum is shown and updated live. Image correlation can be performed supporting the usage of threshold filters and/or region selection. Batch exporting is also available, cross-normalizing the input datasets.
Applications of EDXRF in the conservation of acid papers using a synchrotron light microbeam
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1996
Paper can be produced from various raw materials, which give rise to differences in the permanenc... more Paper can be produced from various raw materials, which give rise to differences in the permanence and durability of the paper product. Modern paper is characterised by a tendency to discolor and become brittle, both problems being generally related to the high acidity of these papers. In order to avoid the loss of historical paper documents to this discoloration and
X-ray energy spectrometry: Application in the study of the ion-exchange kinetics
The International Journal of Applied Radiation and Isotopes, 1977
Abstract The X-ray flourescence analysis induced by small radioisotopic sources has been employed... more Abstract The X-ray flourescence analysis induced by small radioisotopic sources has been employed for the study of the ion-exchange resins kinetics. The advantages offered by this technique over other commonly used methods are (a) variations in the concentration of ions in the resin-bead can be determined without sample taking; and (b) automatic measurements lasting a few seconds provide a check on process trends. The ions trapped in the resin-bead, in various zones of the column, can be expressed analytically, and the result is in good agreement with what can be deduced from a simplified model based on the hypothesis that the exchange process is controlled by diffusion of ions from solution to resin.
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Papers by Giovanni E. Gigante