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1.
Phys Rev Lett ; 125(26): 262301, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33449792

RESUMEN

Flow coefficients v_{n} of the orders n=1-6 are measured with the High-Acceptance DiElectron Spectrometer (HADES) at GSI for protons, deuterons, and tritons as a function of centrality, transverse momentum, and rapidity in Au+Au collisions at sqrt[s_{NN}]=2.4 GeV. Combining the information from the flow coefficients of all orders allows us to construct for the first time, at collision energies of a few GeV, a multidifferential picture of the angular emission pattern of these particles. It reflects the complicated interplay between the effect of the central fireball pressure on the emission of particles and their subsequent interaction with spectator matter. The high precision information on higher order flow coefficients is a major step forward in constraining the equation of state of dense baryonic matter.

2.
Artículo en Inglés | MEDLINE | ID: mdl-34712102

RESUMEN

The precise measurement of cosmic-ray antinuclei serves as an important means for identifying the nature of dark matter and other new astrophysical phenomena, and could be used with other cosmic-ray species to understand cosmic-ray production and propagation in the Galaxy. For instance, low-energy antideuterons would provide a "smoking gun" signature of dark matter annihilation or decay, essentially free of astrophysical background. Studies in recent years have emphasized that models for cosmic-ray antideuterons must be considered together with the abundant cosmic antiprotons and any potential observation of antihelium. Therefore, a second dedicated Antideuteron Workshop was organized at UCLA in March 2019, bringing together a community of theorists and experimentalists to review the status of current observations of cosmic-ray antinuclei, the theoretical work towards understanding these signatures, and the potential of upcoming measurements to illuminate ongoing controversies. This review aims to synthesize this recent work and present implications for the upcoming decade of antinuclei observations and searches. This includes discussion of a possible dark matter signature in the AMS-02 antiproton spectrum, the most recent limits from BESS Polar-II on the cosmic antideuteron flux, and reports of candidate antihelium events by AMS-02; recent collider and cosmic-ray measurements relevant for antinuclei production models; the state of cosmic-ray transport models in light of AMS-02 and Voyager data; and the prospects for upcoming experiments, such as GAPS. This provides a roadmap for progress on cosmic antinuclei signatures of dark matter in the coming years.

3.
Phys Rev Lett ; 123(2): 022002, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31386541

RESUMEN

We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.

4.
Phys Rev Lett ; 114(21): 212301, 2015 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-26066429

RESUMEN

Results on the production of the double strange cascade hyperon Ξ^{-} are reported for collisions of p(3.5 GeV)+Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold Ξ^{-} production is observed in proton-nucleus interactions. Assuming a Ξ^{-} phase-space distribution similar to that of Λ hyperons, the production probability amounts to P_{Ξ^{-}}=[2.0±0.4(stat)±0.3(norm)±0.6(syst)]×10^{-4} resulting in a Ξ^{-}/(Λ+Σ^{0}) ratio of P_{Ξ^{-}}/P_{Λ+Σ^{0}}=[1.2±0.3(stat)±0.4(syst)]×10^{-2}. Available model predictions are significantly lower than the measured Ξ^{-} yield.

5.
Eur Phys J C Part Fields ; 74(10): 2981, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25972760

RESUMEN

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.

6.
Pathologica ; 103(5): 294-8, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22393685

RESUMEN

Primary systemic therapy (PST) adds some practical problems to the pathologic examination of neoplastic breast tissue obtained from patients before and after chemotherapy. Pathologists, oncologists, breast surgeons, radiotherapists and radiologists in the Marche Region held a Consensus Meeting in Ancona on May 13, 2010, in which 15 statements dealing with neoadjuvant chemotherapy were approved by all participants. The first two statements are related to the pre-PST phase and concern the technical procedures and the histological report of the core biopsy. The other statements deal with similar issues of the post-PST surgical specimen.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Mastectomía/métodos , Terapia Neoadyuvante/métodos , Informe de Investigación/normas , Neoplasias de la Mama/clasificación , Femenino , Humanos , Metástasis Linfática , Clasificación del Tumor
7.
Phys Rev Lett ; 103(13): 132301, 2009 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-19905504

RESUMEN

We report first results on a deep subthreshold production of the doubly strange hyperon Xi;{-} in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar + KCl was studied with the High Acceptance Di-Electron Spectrometer at SIS18/GSI. A high-statistics and high-purity Lambda sample was collected, allowing for the investigation of the decay channel Xi;{-} --> Lambdapi;{-}. The deduced Xi;{-}/(Lambda + Sigma;{0}) production ratio of (5.6 +/- 1.2_{-1.7};{+1.8}) x 10;{-3} is significantly larger than available model predictions.

8.
Phys Rev Lett ; 102(18): 182501, 2009 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-19518864

RESUMEN

The K0 meson production by pi(-) mesons of 1.15 GeV/c momentum on C, Al, Cu, Sn, and Pb nuclear targets was measured with the FOPI spectrometer at the Schwer-Ionen-Synchrotron accelerator of GSI. Inclusive production cross sections and the momentum distributions of K0 mesons are compared to scaled elementary production cross sections and to predictions of theoretical models describing the in-medium production of kaons. The data represent a new reference for those models, which are widely used for interpretation of the strangeness production in heavy-ion collisions. The presented results demonstrate the sensitivity of the kaon production to the reaction amplitudes inside nuclei and point to the existence of a repulsive KN potential of 20+/-5 MeV at normal nuclear matter density.

9.
Phys Rev Lett ; 98(5): 052302, 2007 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-17358850

RESUMEN

The invariant-mass spectrum of e+e- pairs produced in 12C+12C collisions at an incident energy of 2 GeV per nucleon has been measured for the first time. The measured pair production probabilities span over 5 orders of magnitude from the pi(0)-Dalitz to the rho/omega invariant-mass region. Dalitz decays of pi(0) and eta account for all the yield up to 0.15 GeV/c(2), but for only about 50% above this mass. A comparison with model calculations shows that the excess pair yield is likely due to baryon-resonance and vector-meson decays. Transport calculations based on vacuum spectral functions fail, however, to describe the entire mass region.

10.
J Exp Clin Cancer Res ; 24(4): 541-6, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16471316

RESUMEN

In the present study, we report results of 28 rectal cancer patients, aged 70 years and older, treated with preoperative radiotherapy and 5FU concomitant chemotherapy. Twenty-eight out of 136 patients treated in our Department between 1997 and 2004 aged > or = 70 years, mean 73 (range 70-81); 3 T2, 18 T3, 7 T4; 15 N0, 5N1, 8 N2; Radiotherapy (5040 cGy, 28 fractions) was delivered combined with 5FU - based concomitant chemotherapy. Compliance to chemoradiotherapy was excellent. Major acute toxicity (> or = G3) evaluation showed haematological Grade 3 only in 2 patients. No severe acute Gastrointestinal toxicity was observed. All patients underwent surgery without severe perioperative complications. Complete pathological response pT0 was found in 3 patients (11%). Overall T downstaging occurred in 61% of the cases. Mean follow up was 34 months (range 4- 84). Kaplan Meier Overall Survival and Disease Free Survival at 5 years were 74% (95% CI 54 -95) and 65% (95% CI 38-93), respectively. Only 1 patient showed G3 diarrhea according to CTCAE that interfered with his Quality of Life and required hospitalization. In conclusion, concomitant radiochemotherapy 5FU based is safe in rectal cancer patients aged > or = 70 with a good tumour downstaging (61% of patients) and excellent feasibility. No treatment related death was observed.


Asunto(s)
Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/cirugía , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante , Terapia Combinada , Supervivencia sin Enfermedad , Humanos , Terapia Neoadyuvante , Radioterapia Adyuvante , Análisis de Supervivencia
11.
Phys Rev Lett ; 87(7): 072701, 2001 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-11497888

RESUMEN

The energetic proton emission has been investigated as a function of the reaction centrality for the system (58)Ni + (58)Ni at 30A MeV. Extremely energetic protons (E(NN)(p) > or = 130 MeV) were measured and their multiplicity is found to increase almost quadratically with the number of participant nucleons, thus indicating the onset of a mechanism beyond one- and two-body dynamics.

12.
Minerva Med ; 84(11): 603-14, 1993 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-8015688

RESUMEN

Findings were reviewed of 518 female patients with carcinoma of the body of the uterus treated and followed up during the 12 year period 1970-1982. For the patients treated with total hysterectomy and bilateral salpingo-oophorectomy followed by postoperative radiation therapy, the five-year overall survival was 88% for stage I histologic grade G1, as compared with 73% for stage I grade G2 + G3 and 48% for stages II + III. The survival rates were also analyzed in terms of myometrial infiltration. The rates of pelvic and paraaortic nodal metastases were analyzed; these observations suggested that routine postoperative radiotherapy should be considered.


Asunto(s)
Histerectomía , Neoplasias Uterinas/radioterapia , Neoplasias Uterinas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Neoplasias Uterinas/patología
13.
Minerva Med ; 83(6): 333-46, 1992 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-1321369

RESUMEN

Findings were reviewed of 1566 female patients with primary breast carcinoma treated with radical or total mastectomy followed by postoperative radiation therapy during the 22 year period 1960-82. The five-year overall survival for the axillary node-positive breast cancer group was 58.3 percent, as compared with 79.9 percent for the node-negative group. The survival rates were also analyzed in terms of age of the patients and number of the axillary positive nodes present. The ratios of observed deaths to expected deaths were turned from many times greater than unity into nearly the expected number, after ten year follow-up period. These findings showed that host factors are capable of destroying tumor cells both in node-negative and in node-positive patients. The significance of axillary negative nodes was emphasized. The rates of locoregional recurrences and distant metastases for node-negative patients were analyzed; these observations suggested that routine postoperative radiotherapy should be considered also in node-negative breast cancer patients.


Asunto(s)
Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Carcinoma Intraductal no Infiltrante/radioterapia , Carcinoma Intraductal no Infiltrante/cirugía , Carcinoma/radioterapia , Carcinoma/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Carcinoma/mortalidad , Carcinoma Intraductal no Infiltrante/mortalidad , Niño , Radioisótopos de Cobalto/uso terapéutico , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Mastectomía Radical , Mastectomía Simple , Persona de Mediana Edad , Modelos Estadísticos , Metástasis de la Neoplasia , Cuidados Posoperatorios , Teleterapia por Radioisótopo , Dosificación Radioterapéutica , Factores de Tiempo
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