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The δ 13 C profile of Globigerinoides ruber , measured in the GT90/3 shallow-water Ionian sea core and dated with high precision, is presented and analyzed using the Singular Spectrum Analysis and the Wavelet Transform. This time series covers the period 200–1979 AD, with a resolution of 3.87 years. The δ 13 C of foraminifera depends on the photosynthetic activity of the symbiontic algae living on the shells, strictly related to the illumination of the sea-surface. Both spectral methods, besides an 11-years oscillation in phase with the Schwabe cycle of the solar activity, show the presence of a centennial cycle that is in phase with the amplitude modulation of the sunspot number series in the last 300 years. Moreover, another climatic record, the tree ring δ 13 C of a Japanese cedar covering the time interval 125–1952 AD, shows a similar centennial oscillation and therefore suggests that this climatic variation is global and in phase with the solar activity.

Extensive Air Showers at large zenith angles θ > 70° (Horizontal Air Showers, HAS) are observed at the EAS-TOP array at Campo Imperatore (Gran Sasso Laboratories). The rate of these events exceeds the one due to primary cosmic rays (at this angles) and therefore these showers have to be generated by penetrating particles. Assuming that they are produced by atmospheric muons we derived the muon flux as Fμ(> 30 TeV) = 1.1 × 10−11cm−2s−1sr−1, in good agreement with the underground measurements. The upper limits for diffuse neutrino radiation from these measurements is Iν(> 105GeV) dI ν e (E 0 )/dE ν e −18 cm −2 s −1 sr −1 GeV −1 , for the resonant ( E 0 = m W 2 2m e = 6.4 × 10 6 GeV ) neutrinos.

The evolution of the cosmic ray primary composition in the energy range 10 6 –10 7 GeV (i.e. the “knee” region) is studied by means of the e.m. and muon data of the Extensive Air Shower EAS-TOP array (Campo Imperatore, National Gran Sasso Laboratories). The measurement is performed through: (a) the correlated muon number ( N μ ) and shower size ( N e ) spectra, and (b) the evolution of the average muon numbers and their distributions as a function of the shower size. From analysis (a) the dominance of helium primaries at the knee, and therefore the possibility that the knee itself is due to a break in their energy spectrum (at E k He =(3.5±0.3)×10 6 GeV) are deduced. Concerning analysis (b), the measurement accuracies allow the classification in terms of three mass groups: light (p,He), intermediate (CNO), and heavy (Fe). At primary energies E 0 ≈10 6 GeV the results are consistent with the extrapolations of the data from direct experiments. In the knee region the obtained evolution of the energy spectra leads to: (i) an average steep spectrum of the light mass group ( γ p,He >3.1), (ii) a spectrum of the intermediate mass group harder than the one of the light component ( γ CNO ≃2.75, possibly bending at E k CNO ≈(6–7)×10 6 GeV), (iii) a constant slope for the spectrum of the heavy primaries ( γ Fe ≃2.3–2.7) consistent with the direct measurements. In the investigated energy range, the average primary mass increases from 〈ln A 〉=1.6–1.9 at E 0 ≃1.5×10 6 GeV to 〈ln A 〉=2.8–3.1 at E 0 ≃1.5×10 7 GeV. The result supports the standard acceleration and propagation models of galactic cosmic rays that predict rigidity dependent cut-offs for the primary spectra of the different nuclei. The uncertainties connected to the hadronic interaction model (QGSJET in CORSIKA) used for the interpretation are discussed.

UHE cosmic rays are studied by means of the detectors of the different components of secondaries produced by their interactions in the atmosphere (EAS). We describe and discuss the reconstruction techniques and accuracies of the e.m. detector of EAS-TOP. They allow, besides independent high resolution measurements of UHE γ-ray astronomy, good correlation possibilities with the detectors of the different EAS components.

Images of atmospheric EAS Cherenkov light have been recorded in connection with the EAS-TOP experiment. We describe the technique (based on a multianode photomultiplier Philips XP4702) and present some preliminary data analysis.

The current role of chemotherapy in pancreatic carcinoma is limited, and progress in the treatment of this disease represents a significant challenge to medical oncology. The most promising drug under study is gemcitabine, a relatively new antimetabolite that represents an attractive candidate for combination chemotherapy because of its excellent side-effect profile and the absence of overlapping toxicities with other chemotherapeutic agents. Combined administration of gemcitabine and anthracyclines could result in the induction of DNA breaks that are not easily repaired by the cell's machinery, thus enhancing the apoptotic signals triggered by these lesions. Forty-four patients with locally advanced and/or metastatic pancreatic adenocarcinoma were enrolled in this multicenter study. Patients received Epirubicin 20 mg m−2 for 3 weeks followed by 1 week of rest (1 cycle) and gemcitabine 1000 mg m−2 after Epirubicin on the same day. All were assessable for toxicity and response, 11 patients responded to treatment with one complete response and 10 partial responses, for an overall response rate of 25%. Median survival was 10.9 months (range, 2–26 months). Therapy was well tolerated, with a low incidence of haematologic grade >2 toxicity. A total of 12 of 27 (44.4%) eligible patients attained a clinical benefit response. Our findings suggest that the gemcitabine-epirubicin schedule is active and well tolerated in patients with advanced pancreatic cancer. British Journal of Cancer (2002) 87, 497–501. doi:10.1038/sj.bjc.6600482 www.bjcancer.com © 2002 Cancer Research UK

On February 23, 1989, an excess of counts of > 100 TeV Extensive Air Showers has been recorded from the direction of the Crab Nebula by three independent detectors: Baksan (North Caucasus, USSR), KGF (India) and EAS-TOP (Gran Sasso, Italy). The chance probability of the combined detection is ~ 10-7. We discuss the EAS-TOP observations from the statistical point of view (chance probability ≤ 10-2) and present some phenomenological characteristics of the events.

We demonstrate the presence of solar flare as well as neutron capture effects in the isotopic composition of rare gases in the Fermo regolith breccia acquired on its parent body based on the measurements of tracks, rare gases and radionuclides. The track density along a 3.2 cm long core decreases by a factor of about 6 and by more than a factor of 13 within the meteorite, indicating small (2-9 cm) and asymmetrical ablation. Rare gases show a large trapped component; the isotopic ratios, particularly 20 Ne/ 22 Ne ≅ 11 and 20 Ne/ 36 Ar = 10 are indicative of a solar component. The galactic cosmic-ray exposure age is determined to be 8.8 Ma. Activities of a dozen radionuclides ranging in half-life from 16 day 48 V to 0.73 Ma 26 Al are consistent with their expected production rates. Track, rare gas and radionuclide data show that the meteoroid was a small body (≤ 120 kg) and had a simple, one-stage exposure history to cosmic rays in the interplanetary space. However, 82 Kr and 128 Xe show an excess due to neutron irradiation on the parent body of the meteorite. The presence of solar gases and the neutron capture effects indicate several stages of irradiation on the parent asteroid. The chemical composition of Fermo confirms that it belongs to the H group of ordinary chondrites with lithic clasts having varying compositions. δ 15 N is found to be 8.3 ± 1.2%0, close to the typical values observed in H chondrites.

A search for transient point sources of ultra-high-energy (UHE) γ-rays has been performed, based on the correlation of two extensive air shower arrays, BAKSAN (North Caucasus, 1700 m a.s.l., BAKSAN Neutrino Observatory, Russia) and EAS-TOP (Campo Imperatore, 2005 a.s.l., Laboratori Nazionali del Gran Sasso, Italy), which are located at very similar latitudes (φ≈43° N), and separated in longitude by Δλ≈33.7°. The search has been conducted at primary energy Eγ⩾5×1013 eV on the time scale of a daily source transit over the sky, observable in the northern hemisphere (19° The stability of the single detectors has been studied and verified up to high significance level. No coincident excess, not compatible with the expectations from statistical fluctuations, has been observed. The obtained upper limits to the rate of transient events, nγ, at 90% c.l., are • concerning the sky survey, in the declination band corresponding to the zenith, n γ /(Ωt) /(yr sr) with Φγ(Eγ>5×1013 eV)>2.0×10−11 cm −2 s−1 and duration Δt • concerning the candidate sources, e.g., for Markarian 421: nγ/t 5×1013 eV)>1.3×10−11 cm −2 s−1 and Δt A coincident episode from Markarian 421, observed on 15 January, 1994, with expected chance imitation rate nch= 0.01 is discussed.

The break observed in the electron shower size power law spectrum of Extensive Air Showers (EAS) at corresponding primary energy E-0 similar to (3 - 5)10(15) eV ("knee") is studied in different EAS components (electromagnetic and muonic) and at different atmospheric depths. A consistent description is obtained. The interpretation of data in terms of primary composition, and following the most accepted high energy interaction models, leads to an increasing average primary mass in this energy range. The study of such behaviour is expected to provide a crucial information for the understanding of the physical parameters that characterize the break for the different primaries.

The cross section for large p t jet production for transverse momentum 10≤ p t ≤20 GeV/c and rapidity 1.6≤ η ≤2.6 in p – N ( p –`air') interactions is studied from the analysis of multicore Extensive Air Showers recorded in the EAS–TOP calorimeter. The projectiles are the leading particles interacting at atmospheric depths between 250 and 480 cm −2 , the CMS energy of interaction being s ≈500 GeV. The slope of the p t distribution agrees with the expected one from the p – p collider data at the same CMS energy. The measured jet production cross section in p – N interactions with respect to p – p interactions is (dσ/dp t ) pN jet =(dσ/dp t ) p p jet ·A α with α =1.56±0.07 for A =14.7 (average mass number of `air' nuclei). Such value is compatible within the experimental uncertainties with the one obtained in p –nucleus accelerator measurements at s ≃30 GeV in the same range of transverse momentum and rapidity. No indication of increase of α with energy, i.e. of the entity of the `Cronin effect', is found.

The amplitude and phase of the first harmonic of the sidereal anisotropy of cosmic rays at E 0 = 2·10 14 eV have been measured by the EAS-TOP experiment (Campo Imperatore, 2005 m a.s.l., LNGS, Italy) and are respectively (at the equatorial plane): A sid = (3.73±0.57)·10 −4 ; φ sid = 1.82±0.49 h lst, with significance 6.5 s.d. The result is supported by different consistency checks. From the comparison with lower energy data, it follows that the amplitude and the phase of the cosmic ray anisotropy are constant over the energy range 10 12 – 2·10 14 eV. This implies at these energies a constant influence of the local interstellar medium on the propagation of cosmic rays.

The cosmic ray energy spectrum in the range E-o = 10(15)-10(16) eV (including the region of the steepening, "knee") is studied by means of the EAS-TOP array (Campo Imperatore, Gran Sasso Laboratories, atmospheric depth 820 g cm(-2)). Measurements of the electromagnetic size (N-e = total number of charged particles at the observation level) are performed as a function of zenith angle with statistical accuracies of a few percent. The change of slope of the spectrum is observed in each bin of zenith angle at size values decreasing with increasing atmospheric depth. Its attenuation is compatible with the one of shower particles (Lambda(e) = 219 +/- 3 g cm(-2)). This observation provides a consistency check, supporting a normal behaviour of showers at the break, that make plausible astrophysical interpretations based on an effect on primaries occurring at a given primary energy. The break has a "sharp" shape (i.e., within experimental errors is compatible with two intersecting power laws) that represents a constraint with which any interpretation has to match. The change of slope of the power law index reproducing the size spectrum is Delta gamma = 0.40 +/- 0.09. The derived all particle energy spectrum is in good agreement with the extrapolation of the direct measurements at low energies and with other EAS data at and above the knee. Power laws fits to the energy spectrum below and above the knee give tin units of m(-2) s(-1) sr(-1) TeV-1) S(E-o) = (3.48 +/- 0.06) x 10(-10) (E-o/2300)(-2.76+/-0.03) for 900 TeV < E-o < 2300 TeV and S(E-o) = (3.77 +/- 0.08) x 10(-11) (E-o/5000)(-3.19+/-0.06) for 5000 TeV < E-o < 10(4) TeV. The systematic uncertainties connected to the interaction model and the primary composition are discussed. (C) 1999 Elsevier Science B.V.

We have previously shown that the very low activity of the cosmogenic 44Ti in meteorites records the galactic cosmic ray (GCR) flux over a century time-scale (Bonino et al., 1995). The heliospheric magnetic field (HMF) variations are the principal source of the GCR modulation in the heliosphere. We present here new measurements which extend our investigation over the last two centuries. The 44Ti activity at the time of fall has been obtained on the basis of the recently revised value of its half-life of 59.2 years. We basically confirm our earlier findings (Bonino et al., 1997). The 44Ti profile, with the time of fall of the meteorites, shows variations in phase in agreement with those expected. The magnitude of oscillations is ∼ 4 times higher than expected (∼ 6%) on the basis of the GCR flux over the past centuries deduced from sunspot number since 1700 and by the neutron monitor and balloon measurements in the last decades. The higher 44Ti production rate during prolonged solar quiet periods (Gleissberg minima) may imply that during these minima the HMF was weaker than during the recent minima of the 11-year solar cycle.

In this paper we present the δ18O profile of Globigerinoides ruber measured in the GT90/3 shallow water Ionian sea core, dated with high precision. The δ18O profile covers the period 1200–1900 AD, with a resolution of 3.87 years. This long record of 700 years of δ18O allows us to identify the imprint of the solar cycle in a climatic record. In fact, the spectral analysis of the time series performed with different methods shows a dominant periodicity of about 11 years with an amplitude of ≈0.07‰. The signal is in opposition to the sunspot number cycle. This component is identified at a high significance level by Monte Carlo Singular Spectrum Analysis (MC-SSA).

We report on a measurement of the ${}^{44}\mathrm{Ti}$ half-life aimed at lowering existing systematic uncertainties in this value, which is important to astrophysics. The half-life was measured by following the decay of ${}^{44}\mathrm{Ti}$ relative to ${}^{60}\mathrm{Co}$ for about 5 yr and the measurements were performed independently in three laboratories---Argonne, Jerusalem, and Torino. We suggest to combine our result, $59.0\ifmmode\pm\else\textpm\fi{}0.6$ yr, with the one from the accompanying Letter by G\"orres et al., $60.3\ifmmode\pm\else\textpm\fi{}1.3$ yr, to obtain a current ``best value'' for the half-life of ${}^{44}\mathrm{Ti}$ of $59.2\ifmmode\pm\else\textpm\fi{}0.6$ yr ( $1\ensuremath{\sigma}$ error).

We tested the effects of daily melatonin treatment on the growth of the ascites hepatoma in rats, determining survival time, cell number and cell cycle phases at various stages of tumor development. Melatonin inhibited cellular proliferation, doubled mean life-time and increased survival. Thymidine incorporation in hepatoma cells from treated rats decreased significantly without changes in the apoptotic index. Flow cytometric analysis showed that melatonin slowed cell cycle progression by increasing the number of cells in phase G0G1. Thus, similar to in vitro models, melatonin's oncostatic action in vivo appears to be directed to specific cell cycle mechanisms, which remain to be elucidated.

The primary cosmic ray (CR) proton, helium and CNO fluxes in the energy range 80-300 TeV are studied at the National Gran Sasso Laboratories by means of EAS-TOP (Campo Imperatore, 2005 m a.s.l.) and MACRO (deep underground, 3100 m w.e., the surface energy threshold for a muon reaching the detector being E-mu(th) approximate to 1.3 TeV). The measurement is based on: (a) the selection of primaries based on their energy/nucleon (i.e., with energy/nucleon sufficient to produce a muon with energy larger than 1.3 TeV) and the reconstruction of the shower geometry by means of the muons recorded by MACRO in the deep underground laboratories; (b) the detection of the associated atmospheric Cherenkov light (C.l.) signals by means of the C.l. detector of EAS-TOP. The C.l. density at core distance r > 100 m is directly related to the total primary energy E-0. Proton and helium ("p + He") and proton, helium and CNO ("p + He + CNO") primaries are thus selected at E-0 approximate to 80 TeV, and at E-0 similar or equal to 250 TeV, respectively. Their flux is measured: J(p+He)(80 TeV) = (1.8 +/- 0.4) x 10(-6) m(-1)-s(-1) sr(-1) TeV-1, and J(p+He+CNO)(250 TeV) = (1.1 +/- 0.3) x 10(-7) m(-2)-s(-1) sr(-1) TeV-1, their relative weights being J(p+He)(J(p+He+CNO)) over bar (250 TeV) = 0.78 +/- 0.17. By using the measurements of the proton spectrum obtained from the direct experiments and hadron flux data in the atmosphere, we obtain for the relative weights of the three components at 250 TeV: J(p) : J(He) : J(CNO) = (0.20 +/- 0.08) : (0.58 +/- 0.19) : (0.22 +/- 0.17). This corresponds to the dominance of helium over proton primaries at 100-1000 TeV, and a possible non-negligible contribution from CNO. The lateral distribution of Cherenkov light in Extensive Air Showers (EASs), which is related to the rate of energy deposit of the primary in the atmosphere, is measured for a selected proton and helium primary beam, and good agreement is found when compared with the one calculated with the CORSIKA/QGSJET simulation model. (C) 2004 Elsevier B.V. All rights reserved.

The primary cosmic ray (CR) proton, helium and CNO fluxes in the energy range 80-300 TeV are studied at the National Gran Sasso Laboratories by means of EAS-TOP (Campo Imperatore, 2005 m a.s.l.) and MACRO (deep underground, 3100 m w.e., the surface energy threshold for a muon reaching the detector being Eμth~1.3 TeV). The measurement is based on: (a) the selection of primaries based on their energy/nucleon (i.e., with energy/nucleon sufficient to produce a muon with energy larger than 1.3 TeV) and the reconstruction of the shower geometry by means of the muons recorded by MACRO in the deep underground laboratories; (b) the detection of the associated atmospheric Cherenkov light (C.l.) signals by means of the C.l. detector of EAS-TOP. The C.l. density at core distance r>100 m is directly related to the total primary energy E0. Proton and helium (``p+He'') and proton, helium and CNO (``p+He+CNO'') primaries are thus selected at E0~=80 TeV, and at E0~=250 TeV, respectively. Their flux is measured: Jp+He(80TeV)=(1.8+/-0.4)×10-6 m-2s-1sr-1TeV-1, and Jp+He+CNO(250TeV)=(1.1+/-0.3)×10-7 m-2s-1sr-1TeV-1, their relative weights being: Jp+He/Jp+He+CNO(250TeV)=0.78+/-0.17. By using the measurements of the proton spectrum obtained from the direct experiments and hadron flux data in the atmosphere, we obtain for the relative weights of the three components at 250 TeV: Jp:JHe:JCNO=(0.20+/-0.08):(0.58+/-0.19):(0.22+/-0.17). This corresponds to the dominance of helium over proton primaries at 100-1000 TeV, and a possible non-negligible contribution from CNO. The lateral distribution of Cherenkov light in Extensive Air Showers (EASs), which is related to the rate of energy deposit of the primary in the atmosphere, is measured for a selected proton and helium primary beam, and good agreement is found when compared with the one calculated with the CORSIKA/QGSJET simulation model.

Production of cosmogenic radioisotopes in meteorites depends on the galactic cosmic ray flux, which is controlled by the heliospheric magnetic field (HMF), which, in turn, depends on the solar activity. The radioisotopes can, therefore, serve as proxy records of the behaviour of the heliosphere in the past, in particular over prolonged solar quiet periods, such as during Gleissberg or Maunder minima, when the production rate of radioisotopes is expected to change significantly. For this purpose we have measured the 44 Ti (T 1/2 =66.6 yr) in ten stony meteorites, which fell between 1840–1992. The results indicate that the production of 44 Ti was significantly higher when the solar activity was persistently low, indicating that the HMF was weak during such periods, enabling higher flux of cosmic rays to enter the inner heliosphere.

Treatment with calcium antagonists has been shown to be beneficial in patients with primary and secondary Raynaud’s phenomenon. A double-blind placebo-controlled crossover trial was performed to assess the efficacy of amlodipine, a new long-acting calcium antagonist, in patients with Raynaud’s phenomenon without underlying disease. 20 of the 24 patients enrolled (20 women and 4 men, mean age 45 years) completed the trial. The number of episodes of Raynaud’s phenomenon per week and the severity of discomfort significantly improved during amlodipine (p < 0.0001 and p < 0.0004, respectively) but not placebo treatment. Perfusion-pressure index, evaluated with Doppler sonography using a postischaemia reactive hyperaemia test, significantly improved (p < 0.04) after treatment with amlodipine but not placebo. These results indicate that amlodipine is a useful treatment for primary and suspected secondary Raynaud’s phenomenon, at least in the short term.

We study sequences of times between successive arrivals of air showers detected in the EAS-TOP experiment (primary energy between 70 and 1000 TeV) in order to establish their nature, whether stochastic or chaotic.

We present the results of a search for Gamma Ray Bursts at energies Eγ ≥ 10 GeV and Eγ ≥ 100 TeV made by the EAS-TOP Air Shower Array in correlation with ∼ 50 events detected by BATSE in the last 3 years.

Different fluxes and spectra of galactic cosmic rays (GCR) and solar cosmic rays result in a wide variety of radioactive and stable-nuclides production rates. The records of cosmic-ray interactions, have been studied in terrestrial archives, in meteorites, cosmic dust and lunar samples. We present here some results obtained in our laboratory on the study of cosmogenic radionuclides produced in meteorites which fell in the last century. The laboratory is situated in the underground station of Monte dei Cappuccini, Torino, at a depth of 70 m water equivalent to reduce the cosmic-ray background level. To measure γ-activity in meteorites we have set up a highly efficient and selective Ge−NaI(Tl) γ-ray spectrometer surrounded by a passive shield. The solar modulation affects the intensity of GCR and therefore the isotopes production rates in meteorites. The 11 y solar cycle is well reproduced by the variations of22Na (T 1/2=2.6 y) in meteorites which fell during the past three solar cycles. The44Ti (T 1/2=66.6 y) activity measured in eight chondrites which fell in the last 110 y is qualitatively consistent with the century-scale solar-activity variation, called the Gleissberg cycle. The increase is roughly four times higher, than expected (about 5%) for a GCR flux calculated by a model in which the solar-activity modulation is determined solely by the sunspot number indexR. This result suggests a much weakened modulation of GCR during the prolonged Gleissberg minimum during which highly ordered magnetic fields set up in the heliosphere.

Purpose: Since metastatic renal cell carcinoma has a poor prognosis and treatment strategies, including hormone therapy, chemotherapy and immunotherapy, have little impact on the quality of life and global survival statistics, new interest has recently focused on the combination of immuno-chemotherapy using pyrimidine analogues, such as gemcitabine.Materials and Methods: In a phase II study 16 patients with metastatic renal cell carcinoma were treated with 1,000 mg./m.2 gemcitabine intravenously on days 1, 8, 15 and 28 for 6 months, 3 MU (1 MU = 1 × 106 IU) interferon (IFN)-α intramuscularly 3 times a week and 4.5 million IU interleukin (IL)-2 subcutaneously daily for 5 days a week for 2 consecutive weeks every month for 6 months. Responding and nonprogressing cases were maintained on immunotherapy consisting of IFN-α and IL-2 for further 6 months.Results: In 15 evaluable patients overall response rate (1 complete response plus 3 partial response) was 28% while stable disease was achieved in 7 (47...

We have measured the thermoluminescence (TL) profile of the Mediterranean Sea core CT85.5 at the same depths where the cosmogenic-isotope10Be production peak at 35 ky BP was found. Strong TL peaks are evident at 37.5 ky and 35.6 ky BP. The Fourier analysis of the TL time series running from 32.5 ky to 42.6 ky at 100 y sampling interval shows 2500 y and 500 y periodicities. We suggest that the Sun was «active» at the time of the10Be enhancement.

A number of marine as well as continental K/T sections in India, particularly around the Deccan volcanic regime, have been analyzed to obtain concentration profiles of some platinum group and other trace elements, specifically to search for anomalous levels of iridium. Except for the Um Sohryngkew River (USR) section in Meghalaya, where iridium is found to occur at an anomalously high level in the K/T boundary layer, all other sections show low levels in the range of 10 to ∼120 pg/g. The iridium profile in the USR section is characterized by a sharp peak of 12.1 ng/g in a 1.5 cm thick limonitic layer, superimposed on a broad band of ∼0.2 ng/g extending over a 50±20 cm thick section, beyond which Ir decreases to the base level of ∼0.02 ng/g, both in the Tertiary as well as in the Cretaceous. High Ir is accompanied by high Os but the Os/Ir ratio in the peak (0.37) is different from the Os/Ir ratio of ∼2 measured in the broad band. The Ir profile in the USR section seems to be consistent with fallout of cometary debris preceding and following the main impact. The measurements at other sites in the Deccan suggest that the iridium inventory of the Deccan is too low to account for the high iridium observed in the KTB layer all over the world, but may be sufficient to give rise to its enhancement adjacent to the KTB peak.

An accurate dating of recent Ionian Sea sediment cores has been performed by the210Pb radiometric method and by a detailed tephroanalysis. The markers of the historical volcanic eruptions which occurred in the Campanian area (Vesuvius, Phlegrean Fields, Ischia) during the last two millenia have been identified along the cores. Among the others, the famous Plinian Vesuvius eruption of 79 AD, which buried the Roman town of Pompei, has been recognized. Direct210Pb dating is limited to the last two centuries. The tephroanalysis demonstrates that the sedimentation rate estimated by the210Pb method is correct and it is constant, at least for the last 2 ky. The presence of the137Cs peak due to the intense activity of nuclear-weapon testing in the atmosphere in 1963–64 AD assures that the top of the core is present and not disturbed. The high precision of the core dating allows to transform the depth scale into a time scale with an accuracy of ∼1%. The analysis of several cores taken in the same area demonstrates that the results presented here are of general validity, at least in this region. The carbonatic mud deposited in the last millennia in the Gallipoli Terrace can be successfully utilized for investigating the environmental conditions in the recent past.

We describe and discuss the operation, calibration and stability of the EAS-TOP calorimeter (Campo Imperatore, National Gran Sasso Laboratories), a large area hadron and muon detector devoted to cosmic-ray physics. It consists of iron slabs (for a total thickness of 818 g cm(-2)) and Iarocci tubes as sensitive layers, operating in the streamer mode and the "quasi proportional" regime. Using a model describing the operation of the "quasi proportional" chambers, we derive a calibration curve in the energy range 50-5000 GeV, whose reliability has been indirectly checked through on-site measurements, by means of an accelerator beam run (up to similar or equal to 600-700 GeV) and by comparing the model predictions on hadron shower transition curves with the data. (C) 1999 Elsevier Science B.V. All rights reserved.