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Study of polarized-e polarized-p --> e-prime p pi0 in the Delta(1232) mass region using polarization asymmetries
A. Biselli
Physics , 2003, DOI: 10.1103/PhysRevC.68.035202
Abstract: Measurements of the angular distributions of target and double spin asymmetries for the Delta(1232) in the exclusive channel (polarized-p polarized-e,e-prime p)pi0 obtained at Jefferson Lab in the Q2 range from 0.5 to 1.5 gev2 are presented. Results of the asymmetries are compared with the unitary isobar model, dynamical models, and the effective Lagrangian theory. Sensitivity to the different models was observed, particularly in relation to the description of background terms on which the target asymmetry depends significantly.
Deeply virtual Compton scattering at Jefferson Laboratory
Angela Biselli
Physics , 2015,
Abstract: The generalized parton distributions (GPDs) have emerged as a universal tool to describe hadrons in terms of their elementary constituents, the quarks and the gluons. Deeply virtual Compton scattering (DVCS) on a proton or neutron ($N$), $e N \rightarrow e' N' \gamma$, is the process more directly interpretable in terms of GPDs. The amplitudes of DVCS and Bethe-Heitler, the process where a photon is emitted by either the incident or scattered electron, can be accessed via cross-section measurements or exploiting their interference which gives rise to spin asymmetries. Spin asymmetries, cross sections and cross-section differences can be connected to different combinations of the four leading-twist GPDs (${H}$, ${E}$, ${\tilde{H}}$, ${\tilde{E}}$) for each quark flavors, depending on the observable and on the type of target. This paper gives an overview of recent experimental results obtained for DVCS at Jefferson Laboratory in the halls A and B. Several experiments have been done extracting DVCS observables over large kinematics regions. Multiple measurements with overlapping kinematic regions allow to perform a quasi-model independent extraction of the Compton form factors, which are GPDs integrals, revealing a 3D image of the nucleon.
First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)
CLAS Collaboration,A. S. Biselli
Physics , 2008, DOI: 10.1103/PhysRevC.78.045204
Abstract: The exclusive channel polarized proton(polarized e,e prime p)pi0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the pi0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A_{1/2} and S_{1/2} for the Roper resonance N(1400)P11, and the N(1535)S11 and N(1520)D13 states.
Regulation of normal human polyrnorphonuclear leucocytes by carnitine
Andrea Fattorossi,Roberto Biselli,Anna Casciaro,Sonia Tzantzoglou
Mediators of Inflammation , 1993, DOI: 10.1155/s0962935193000742
An unusual cause of hypoxaemia in a patient with pneumonia
Bove Tiziana,Crescenzi Giuseppe,Calabro Mariagrazia,Biselli Camilla
Annals of Cardiac Anaesthesia , 2008,
Longitudinal target-spin asymmetries for deeply virtual Compton scattering
E. Seder,A. Biselli,S. Pisano,S. Niccolai,the CLAS Collaboration
Physics , 2014, DOI: 10.1103/PhysRevLett.114.032001
Abstract: A measurement of the electroproduction of photons off protons in the deeply inelastic regime was performed at Jefferson Lab using a nearly 6-GeV electron beam, a longitudinally polarized proton target and the CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for $ep\to e'p'\gamma$ events, which arise from the interference of the deeply virtual Compton scattering and the Bethe-Heitler processes, were extracted over the widest kinematics in $Q^2$, $x_B$, $t$ and $\phi$, for 166 four-dimensional bins. In the framework of Generalized Parton Distributions (GPDs), at leading twist the $t$ dependence of these asymmetries provides insight on the spatial distribution of the axial charge of the proton, which appears to be concentrated in its center. These results also bring important and necessary constraints for the existing parametrizations of chiral-even GPDs.
Clinical profile of children with down syndrome treated in a genetics outpatient service in the southeast of Brazil
Pavarino Bertelli, érika Cristina;Biselli, Joice Matos;Bonfim, Daiana;Goloni-Bertollo, Eny Maria;
Revista da Associa??o Médica Brasileira , 2009, DOI: 10.1590/S0104-42302009000500017
Abstract: objective: considering that studies about the frequencies of phenotypic features of down syndrome (ds) in the brazilian population with large ethnic variability are scarce in literature, this study analyzed clinical and demographic characteristics of ds children from the southeastern region of brazil. methods: sixty-two ds children with free trisomy 21 were evaluated by physical examination using reference values that considered the children′s gender and age at their presentation. data about clinical complications were collected by retrospective analysis of the children's medical records and/or information supplied by their mothers. statistical analysis was performed using likelihood ratio test, with significance level less or equal to 5%. results: clinical features observed in more than 90% of the individuals were flat facial profile, brachycephaly, slanted palpebral fissures, hypotonia at birth and flat nasal bridge. congenital heart disease was present in 56.5% of the cases, verbal language acquisition disorder in 87%, and global delayed development in 77.8%. conclusion: the comparison between our data and related literature showed a great variability of the phenotype features frequencies of ds among studies. besides environmental factors, this can reflect individual as well as population characteristics.
Single and double spin asymmetries for deeply virtual Compton scattering measured with CLAS and a longitudinally polarized proton target
S. Pisano,A. Biselli,S. Niccolai,E. Seder,M. Guidal,M. Mirazita,the CLAS Collaboration
Physics , 2015, DOI: 10.1103/PhysRevD.91.052014
Abstract: Single-beam, single-target, and double-spin asymmetries for hard exclusive photon production on the proton $\vec{e}\vec{p} \to e' p'\gamma$ are presented. The data were taken at Jefferson Lab using the CLAS detector and a longitudinally polarized ${}^{14}$NH$_3$ target. The three asymmetries were measured in 165 4-dimensional kinematic bins, covering the widest kinematic range ever explored simultaneously for beam and target-polarization observables in the valence quark region. The kinematic dependences of the obtained asymmetries are discussed and compared to the predictions of models of Generalized Parton Distributions. The measurement of three DVCS spin observables at the same kinematic points allows a quasi-model-independent extraction of the imaginary parts of the $H$ and $\tilde{H}$ Compton Form Factors, which give insight into the electric and axial charge distributions of valence quarks in the proton.
Social Networks and Collective Intelligence: A Return to the Agora
Manuel Mazzara,Luca Biselli,Pier Paolo Greco,Nicola Dragoni,Antonio Marraffa,Nafees Qamar,Simona de Nicola
Computer Science , 2013,
Abstract: Nowadays, acquisition of trustable information is increasingly important in both professional and private contexts. However, establishing what information is trustable and what is not, is a very challenging task. For example, how can information quality be reliably assessed? How can sources? credibility be fairly assessed? How can gatekeeping processes be found trustworthy when filtering out news and deciding ranking and priorities of traditional media? An Internet-based solution to a human-based ancient issue is being studied, and it is called Polidoxa, from Greek "poly", meaning "many" or "several" and "doxa", meaning "common belief" or "popular opinion". This old problem will be solved by means of ancient philosophies and processes with truly modern tools and technologies. This is why this work required a collaborative and interdisciplinary joint effort from researchers with very different backgrounds and institutes with significantly different agendas. Polidoxa aims at offering: 1) a trust-based search engine algorithm, which exploits stigmergic behaviours of users? network, 2) a trust-based social network, where the notion of trust derives from network activity and 3) a holonic system for bottom-up self-protection and social privacy. By presenting the Polidoxa solution, this work also describes the current state of traditional media as well as newer ones, providing an accurate analysis of major search engines such as Google and social network (e.g., Facebook). The advantages that Polidoxa offers, compared to these, are also clearly detailed and motivated. Finally, a Twitter application (Polidoxa@twitter) which enables experimentation of basic Polidoxa principles is presented.
Superiority of Prothrombin Complex Concentrate versus Frozen Fresh Plasma in Cardiology Patients with Warfarin Intoxication–Observational Study  [PDF]
Alexandre de Matos Soeiro, Maria Cristina César, Bruno Biselli, Aline Siqueira Bossa, T. de Carvalho Andreucci Torres Leal, Maria Carolina Feres de Almeida Soeiro, Carlos V. Serrano, Ludhmila Abra?o Hajjar, Múcio Tavares Oliveira
Open Journal of Emergency Medicine (OJEM) , 2017, DOI: 10.4236/ojem.2017.52007
Abstract: Objective: The objective of this study was to analyse the reversibility of the anticoagulant effect of warfarin by comparing prothrombin complex concentrate (PCC) versus frozen fresh plasma (FFP) in cardiology patients with serious warfarin intoxication. Methods: This was an observational and retrospective study comprising 67 patients (18 in group I [PCC] and 49 in group II [FFP]). The primary endpoint was the reversal of anticoagulant effect of warfarin after 2 and 24 hours of PCC or FFP administration. Comparisons between the groups were made using T-test and Q-square. Multivariate analyses were conducted using logistic regression, and the results were considered significant when p < 0.05. Complementary analysis was performed using the ROC curve, calculating the area under the curve (AUC), and calculating the cut-off score for the relation between PCC (UI/kg) or FFP (ml/kg) and INR reversibility. Results: The medium dose used was 27.6 UI/kg of PCC and 14.5 ml/kg of FFP. Significant differences were observed between groups I and II in the INR reversibility measurements after 2 hours (33.3% vs. 6.1%, p = 0.001) and 24 hours (38.9% vs. 12.2%, p = 0.009) as well as in the occurrence of pulmonary edema (5.6% vs. 42.9%, OR = 11.10, p = 0.04). The AUC for PCC was 0.891 (CI 95% [0.72 - 1.0]), and for FFP, it was 0.291 (CI 95% [0.09 - 0.49]). Conclusions: PCC is better than FFP treatment in reversing the warfarin intoxication after 2 and 24 hours of administration. Furthermore, PCC showed lower pulmonary edema in cardiology patients.
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