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Search Results: 1 - 10 of 189900 matches for " G. Bonfini "
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GALFIT-CORSAIR: implementing the core-Sersic model into GALFIT
P. Bonfini
Physics , 2014, DOI: 10.1086/678566
Abstract: We introduce GALFIT-CORSAIR: a publicly available, fully retro-compatible modification of the 2D fitting software GALFIT (v.3) which adds an implementation of the core-Sersic model. We demonstrate the software by fitting the images of NGC 5557 and NGC 5813, which have been previously identified as core-Sersic galaxies by their 1D radial light profiles. These two examples are representative of different dust obscuration conditions, and of bulge/disk decomposition. To perform the analysis, we obtained deep Hubble Legacy Archive (HLA) mosaics in the F555W filter (~V-band). We successfully reproduce the results of the previous 1D analysis, modulo the intrinsic differences between the 1D and the 2D fitting procedures. The code and the analysis procedure described here have been developed for the first coherent 2D analysis of a sample of core-Sersic galaxies, which will be presented in a forth-coming paper. As the 2D analysis provides better constraining on multi-component fitting, and is fully seeing-corrected, it will yield complementary constraints on the missing mass in depleted galaxy cores.
Studying the asymmetry of the GC population of NGC 4261
P. Bonfini,A. Zezas,M. Birkinshaw,D. M. Worrall,G. Fabbiano,E. O'Sullivan,G. Trinchieri,A. Wolter
Physics , 2012,
Abstract: We present an analysis of the Globular Cluster (GC) population of the elliptical galaxy NGC 4261 based on HST WFPC2 data in the B, V and I bands. We study the spatial distribution of the GCs in order to probe the anisotropy in the azimuthal distribution of the discrete X-ray sources in the galaxy revealed by Chandra images (Zezas et al. 2003). The luminosity function of our GC sample (complete at the 90% level for V_mag = 23.8 mag) peaks at V_mag = 25.1 (-0.6)(+1.0) mag, which corresponds to a distance consistent with previous measurements. The colour distribution can be interpreted as being the superposition of a blue and red GC component with average colours V-I = 1.01 (-0.06)(+0.06) mag and 1.27 (-0.08)(+0.06) mag, respectively. This is consistent with a bimodal colour distribution typical of elliptical galaxies. The red GC's radial profile is steeper than that of the galaxy surface brightness, while the profile of the blue subpopulation looks more consistent with it. The most striking finding is the significant asymmetry in the azimuthal distribution of the GC population about a NE-SW direction. The lack of any obvious feature in the morphology of the galaxy suggests that the asymmetry could be the result of an interaction or a merger.
The Two Dimensional Projected Spatial Distribution of Globular Clusters: Method and Application to NGC4261
R. D'Abrusco,G. Fabbiano,J. Strader,A. Zezas,S. Mineo,T. Fragos,P. Bonfini,B. Luo,D. -W. Kim,A. King
Physics , 2013, DOI: 10.1088/0004-637X/773/2/87
Abstract: We present a new method for the determination of the two-dimensional (2D) projected spatial distribution of globular clusters (GCs) in external galaxies. This method is based on the K-Nearest Neighbor density estimator of Dressler (1980), complemented by MonteCarlo simulations to establish the statistical significance of the results. We apply this method to NGC4261, a "test galaxy" where significant 2D anisotropy in the GC distribution has been reported. We confirm that the 2D distribution of GC is not azimuthally isotropic. Moreover, we demonstrate that the 2D distribution departures from the average GC radial distribution results in highly significant spiral-like or broken shell features. Overall, the same perturbations are found in "red" and "blue" GCs, but with some differences. In particular, we observe a central feature, roughly aligned with the minor axis of NGC4261, composed of red and most luminous GCs. Blue and fainter GCs are more frequent at large radial distances and follow the spiral-like features of the overall density structure. These results suggest a complex merging history for NGC4261.
Megadoses of Sodium Ascorbate Efficiently Kill HL60 Cells in Vitro: Comparison with Arsenic Trioxide  [PDF]
Domenico Mastrangelo, Lauretta Massai, Giuseppe Fioritoni, Antonio Iacone, Paolo Di Bartolomeo, Patrizia Accorsi, Tiziana Bonfini, Michela Muscettola, Giovanni Grasso
Journal of Cancer Therapy (JCT) , 2013, DOI: 10.4236/jct.2013.48162
Abstract:

Arsenic Trioxide (ATO) is widely acknowledged as the treatment of choice for Acute Promyelocytic Leukemia (APL). It is a “two-sided” drug since it can induce differentiation or kill APL and other tumor cells according to the dosage. Part of the cytotoxic effects of ATO on APL cells is due to its pro-oxidant activity, a characteristic which ATO shares with a number of other compounds, including high doses of ascorbate (ASC). In a comparative investigation on the cytotoxic effects of both ATO and ASC on HL60 (APL) cell lines, in Vitro, we have been able to confirm the known cytotoxic effects of ATO, but, more importantly, we have demonstrated that ASC is significantly more effective than ATO, in killing these cancer cells in Vitro, when the concentrations are maintained within the millimolar (mM) range, i.e. the range of plasma concentrations at which ASC induces oxidative damage to tumor cells. Since these plasma levels can be reached only by the intravenous administration of high doses of ASC, we propose that intravenous high doses of ASC may represent a potentially revolutionary new approach in the management of APL.

Serological screening of Coxiella burnetii (Q fever) and Brucella spp. in sheep flocks in the northern prefectures of Japan in 2007
Massimo Giangaspero,Takeshi Osawa,Barbara Bonfini,Riccardo Orusa
Veterinaria Italiana , 2012,
Abstract: Ovine sera collected from the northern Prefectures of Hokkaido, Iwate and Aomori in Japan, were examined for the presence of antibodies against Coxiella burnetii (Q fever) using the complement fixation test and, against Brucella spp., using both the rapid serum agglutination test and the complement fixation test. None of the sera tested were serologically positive to Brucella spp. A total of 21 animals (8.64%) out of 243 samples tested were seropositive to the C. burnetii antigen. Levels of infection were observed in all of the three Prefectures and in ten flocks of the fourteen sampled. Although no diagnostic measures were in place, the infection could not be linked to losses in sheep production or to the decreased fertility in ewes, a lower lambing rate and mortality in lambs. These data confirmed that Q fever is widespread in the sheep population in the area studied. Considering the zoonotic potential of the disease, further studies to investigate the epidemiology of Q fever in this region are required.
Sviluppo e valutazione di test diagnostici per la sierodiagnosi di brucellosi suina
Tiziana Di Febo,Mirella Luciani,Ottavio Portanti,Barbara Bonfini
Veterinaria Italiana , 2012,
Abstract: Sono stati sviluppati una ELISA competitiva (c-ELISA), una ELISA indiretta (i-ELISA) e un test immunologico DELFIA (Dissociation-Enhanced Lanthanide Fluorescence Immunoassay) per la ricerca di anticorpi verso Brucella suis in sieri di maiale e cinghiale. I tre test prevedono l’utilizzo di un anticorpo monoclonale (MAb 4B5A) verso l’LPS di Brucella (c-ELISA e DELFIA) e di un anticorpo monoclonale (MAb 10C2G5) verso le IgG suine (i-ELISA). La specificità (Sp) e la sensibilità (Se) dei tre test sono le seguenti: per la c-ELISA Se e Sp = 100% con un valore di cut-off pari al 61.0% (B/B0%); per la i-ELISA Sp = 99.1% e Se = 100% con un valore di cut-off di 21.7% (PP%); per il DELFIA Sp = 91.0% e Se = 75% ponendo il valore di cut-off al 37.0% (B/B0%). Inoltre sono state valutate le performance, nei confronti di sieri suini, di un test FPA (Fluorescence Polarization Assay) commerciale sviluppato per la ricerca di anticorpi anti-Brucella in sieri bovini; la specificità e la sensibilità ottenute sono entrambe del 100% al valore di cut-off di 99.5 (mP). Questi risultati suggeriscono che la combinazione di c-ELISA, i-ELISA e FPA può essere utilizzata per migliorare la diagnosi di brucellosi suina.
Standardisation of an indirect enzyme-linked immunosorbent assay for the detection
Manuela Tittarelli,Barbara Bonfini,Fabrizio De Massis,Armando Giovannini
Veterinaria Italiana , 2011,
Abstract: An indirect enzyme-linked immunosorbent assay (ELISA) was evaluated for the detection of Brucella antibodies in milk from water buffalo (Bubalus bubalis Linnaeus, 1758). The test accuracy was evaluated on milk samples from the Campania Region in Italy. A total of 100 negative samples were collected from 10 officially brucellosis-free herds in Salerno Province, while 30 positive samples were collected from 3 herds in Caserta Province, where animals gave positive results to the official tests and it was here that Brucella abortus biovar 1 had been isolated. Test sensitivity was 100%, with a confidence interval (CI) of 90.8%-100%, while specificity was 98% (CI 93%-99.4%) on individual milk samples. To simulate bulk milk samples from herds infected at various levels of infection, dilutions from 1:10 to 1:100 of positive milk samples in negative milk were also used. The probability of detecting antibodies in positive milk samples was higher than 50% up to a dilution of 1:50 in negative milk. Considering the average national water buffalo herd size, the probability of identifying infection in a water buffalo herd by bulk milk testing is 50% (CI 33.1%-66.9%) in the worst case scenario of a single infected animal contributing to the bulk milk.
Standardizzazione di un test ELISA indiretto per la ricerca di anticorpi brucellari nel latte di bufala (Bubalus bubalis) in Italia
Manuela Tittarelli,Barbara Bonfini,Fabrizio De Massis,Armando Giovannini
Veterinaria Italiana , 2011,
Abstract: è stata valutato un test ELISA indiretto per rilevare la presenza di anticorpi brucellari nel latte di bufala (Bubalus bubalis Linnaeus, 1758). L’accuratezza della prova è stata valutata su latte proveniente da allevamenti bufalini campani. Sono stati impiegati 100 campioni negativi provenienti da dieci allevamenti ufficialmente indenni della provincia di Salerno e 30 campioni positivi provenienti da tre allevamenti della provincia di Caserta con animali positivi ai test ufficiali e presenza di Brucella abortus biovar 1. La sensibilità della prova è stata del 100% (intervallo di confidenza [IC] del 90,8%-100%) e la specificità sui campioni di latte individuale è stata del 98% (IC 93%-99,4%). Al fine di simulare campioni di latte di massa provenienti da allevamenti infetti a varie prevalenze di infezione, sono state analizzate diluizioni da 1:10 a 1:100 di campioni di latte positivo in latte negativo. La probabilità di rilevare anticorpi in campioni di latte positivo è risultata superiore al 50% fino alla diluizione 1:50 in latte negativo. Considerando la consistenza media nazionale degli allevamenti bufalini, la probabilità di individuare l’infezione in un allevamento, ricorrendo alla prova ELISA su latte di massa, è risultata del 50% (IC 33,1%-66,9%) qualora nel latte di massa fosse presente il latte di un solo animale infetto.
Uso della chemiluminescenza per la diagnosi della brucellosi bovina e ovina mediante ELISA indiretta e competitiva
Manuela Tittarelli,Barbara Bonfini,Romolo Salini,Maria Magliulo
Veterinaria Italiana , 2008,
Abstract: I metodi ufficiali previsti dal Piano nazionale di eradicazione della brucellosi bovina ed ovi-caprina sono la sieroagglutinazione rapida (SAR) con l’antigene acidificato al Rosa Bengala e la fissazione del complemento (FDC). Nella attuale fase del piano di eradicazione non è infrequente imbattersi in risultati di difficile interpretazione ottenuti con i test ufficiali, pertanto è necessario poter disporre di test aggiuntivi che presentino livelli di specificità e di sensibilità più elevati. A questo scopo sono stati validati due metodi ELISA, indiretto (i-ELISA CL) e competitivo (c-ELISA CL), mediante l’utilizzo di un substrato chemiluminescente per la determinazione di anticorpi anti-Brucella in siero bovino ed ovino. I metodi si basano sulla rivelazione degli anticorpi anti-Brucella, contenuti nel siero, mediante la catalisi di un substrato enzimatico chemiluminescente (sistema luminolo/H2O2/ enhancer), da parte della perossidasi coniugata ad anticorpi secondari anti-IgG, nella i-ELISA CL, o al monoclonale anti-LPS, nella c-ELISA CL. Sulla base dei risultati ottenuti, per l'i-ELISA CL è stato stabilito un valore di cut-off, espresso come percentuale di positività (PP), del 60% per i sieri bovini e del 37,5% per quelli ovini; con questo valore di cut-off si ottiene una sensibilità ed una specificità del test del 100% per i sieri bovini, e una sensibilità del 100% e una specificità del 99,8% per quelli ovini. Per la c-ELISA CL è stato scelto un cut-off, espresso come percentuale di inibizione (PI), del 30% per i sieri bovini e del 40% per quelli ovini, che assicura valori di sensibilità e specificità del 100% in entrambi i casi.
An ELISA for the evaluation of gamma interferon production in cattle vaccinated with Brucella abortus strain RB51
Manuela Tittarelli,Fabrizio De Massis,Barbara Bonfini,Mauro Di Ventura
Veterinaria Italiana , 2009,
Abstract: The results of an enzyme-linked immunosorbent assay (ELISA) implemented for the detection of gamma interferon (g-interferon) production in cattle vaccinated with Brucella abortus strain RB51 are presented. A purified protein fraction derived from RB51 (RB51 brucellin) has been used as antigenic stimulus for whole blood. The test was evaluated for 300 days in ten heifers vaccinated at calfhood with 10 × 109 colony-forming units of RB51 and in five control heifers. All animals came from officially brucellosis-free herds. Vaccinated animals started to give positive results from day 17 post vaccination (pv) until day 239 pv. All vaccinated animals gave a positive reaction at least once (with a stimulation index exceeding 2.5). Nevertheless, if sampling on day 20 pv is excluded (90% of vaccinated animals gave positive results), the sensitivity of the test varies from 20% to 70%, with a 40% average. A stimulation index over 2.5 was also recorded in three control animals. The results suggest that the g-interferon test is not suitable for the detection of cattle vaccinated with RB51, either at the individual or at the herd level.
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