Accelerator and reactor neutrino experiments

Neutrino experiments at reactors and accelerators have provided a wealth of physics results and will continue to do so in the future. Over the next decade, these experiments will focus on oscillation studies. They will verify that the atmospheric neutrino results are indeed associated with oscillations and will provide more precise measurements of the oscillation parameters. They will also verify the large mixing angle MSW solution of the solar neutrino problem and provide information on the existence (or non-existence) of the fourth, sterile neutrino which is required if three independent Delta M/sup 2/ values are needed to explain all the observed oscillation signals. (34 refs)

Correlations in high transverse momentum final states

The author reviews experiments and results in the study of particle correlations in high energy collisions leading to high transverse momentum secondaries. Most of the effects observed in opposite direction with respect to that of a high p/sub perpendicular to / hadron, can be largely explained in terms of kinematic effects. These effects have made any search for jets of hadrons opposite to a high p /sub perpendicular to / hadron inconclusive-on the other hand, the positive momentum correlations observed between two high p/sub perpendicular to / hadrons in the same azimuthal region, are certainly of dynamical origin and must be studied further. (9 refs)

The birth of lepton universality and the second neutrino

Bruno Pontecorvo has given many important contributions to particle physics, two of which were closely related to my work at the beginning of my career. I will discuss them here and I will also describe my first meeting with Bruno in 1973, on the occasion of a visit to Dubna

Fibroblastic rheumatism: a case without rheumatological symptoms.

Fibroblastic rheumatism is a rare syndrome characterized by the association of multiple cutaneous nodules with symmetric polyarthritis. We report on a patient who presented a 4-year history of pink to skin-coloured nodular lesions symmetrically localized at para-articular sites without evident rheumatological symptoms. Histopathology of a skin nodule led to the diagnosis of fibroblastic rheumatism showing a poorly circumscribed dermal proliferation of spindle and stellate fibroblast-like cells embedded in thickened collagen bundles with a marked reduction of elastic fibres. X-rays of both hands and feet showed metacarpophalangeal, metatarsalphalangeal and interphalangeal erosions, unexpected by patient history. This case of fibroblastic rheumatism appears unique in view of the absence of any clinical manifestation of polyarthritis at 7 years from appearance of skin lesions

Investigating serum and tissue expression identified a cytokine/chemokine signature as a highly effective melanoma marker

The identification of reliable and quantitative melanoma biomarkers may help an early diagnosis and may directly affect melanoma mortality and morbidity. The aim of the present study was to identify effective biomarkers by investigating the expression of 27 cytokines/chemokines in melanoma compared to healthy controls, both in serum and in tissue samples. Serum samples were from 232 patients recruited at the IDI-IRCCS hospital. Expression was quantified by xMAP technology, on 27 cytokines/chemokines, compared to the control sera. RNA expression data of the same 27 molecules were obtained from 511 melanoma-and healthy-tissue samples, from the GENT2 database. Statistical analysis involved a 3-step approach: analysis of the single-molecules by Mann–Whitney analysis; analysis of paired-molecules by Pearson correlation; and profile analysis by the machine learning algorithm Support Vector Machine (SVM). Single-molecule analysis of serum expression identified IL-1b, IL-6, IP-10, PDGF-BB, and RANTES differently expressed in melanoma (p < 0.05). Expression of IL-8, GM-CSF, MCP-1, and TNF-α was found to be significantly correlated with Breslow thickness. Eotaxin and MCP-1 were found differentially expressed in male vs. female patients. Tissue expression analysis identified very effective marker/predictor genes, namely, IL-1Ra, IL-7, MIP-1a, and MIP-1b, with individual AUC values of 0.88, 0.86, 0.93, 0.87, respectively. SVM analysis of the tissue expression data identified the combination of these four molecules as the most effective signature to discriminate melanoma patients (AUC = 0.98). Validation, using the GEPIA2 database on an additional 1019 independent samples, fully confirmed these observations. The present study demonstrates, for the first time, that the IL-1Ra, IL-7, MIP-1a, and MIP-1b gene signature discriminates melanoma from control tissues with extremely high efficacy. We therefore propose this 4-molecule combination as an effective melanoma marker

The CAST Time Projection Chamber

One of the three X-ray detectors of the CAST experiment searching for solar axions is a Time Projection Chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity X-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is safely set during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62 %. Shielding has been installed around the detector, lowering the background level to 4.10 x 10^-5 counts/cm^2/s/keV between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion-photon coupling and mass.Comment: 19 pages, 11 figures and images, submitted to New Journal of Physic