Pressure dependence of the superconducting transition and electron correlations in Na_xCoO_2 \cdot 1.3H_2O

We report T_c and ^{59}Co nuclear quadrupole resonance (NQR) measurements on the cobalt oxide superconductor Na_{x}CoO_{2}\cdot 1.3H_{2}O (T_c=4.8 K) under hydrostatic pressure (P) up to 2.36 GPa. T_c decreases with increasing pressure at an average rate of -0.49\pm0.09 K/GPa. At low pressures P\leq0.49 GPa, the decrease of T_c is accompanied by a weakening of the spin correlations at a finite wave vector and a reduction of the density of states (DOS) at the Fermi level. At high pressures above 1.93 GPa, however, the decrease of T_c is mainly due to a reduction of the DOS. These results indicate that the electronic/magnetic state of Co is primarily responsible for the superconductivity. The spin-lattice relaxation rate 1/T_1 at P=0.49 GPa shows a T^3 variation below T_c down to T\sim 0.12T_c, which provides compelling evidence for the presence of line nodes in the superconducting gap function.Comment: published on 19, Sept. 2007 on Phys. Rev.

Lateral distribution of high energy hadrons and gamma ray in air shower cores observed with emulsion chambers

A high energy event of a bundle of electrons, gamma rays and hadronic gamma rays in an air shower core were observed. The bundles were detected with an emulsion chamber with thickness of 15 cm lead. This air shower is estimated to be initiated with a proton with energy around 10 to the 17th power to 10 to the 18th power eV at an altitude of around 100 gmc/2. Lateral distributions of the electromagnetic component with energy above 2 TeV and also the hadronic component of energy above 6 TeV of this air shower core were determined. Particles in the bundle are produced with process of the development of the nuclear cascade, the primary energy of each interaction in the cascade which produces these particles is unknown. To know the primary energy dependence of transverse momentum, the average products of energy and distance for various average energies of secondary particles are studied

High number of circulating CD34+ cells in patients with myelophthisis.

Hematopoietic Stem Cells High number of circulating CD34+ cells in patients with myelophthisis Six patients with bone marrow micrometastases from solid cancers presented with increased numbers of circulating CD34+ cells; the CD34+ cell counts were very high in some cases. By contrast, no patient with metastatic cancer without bone marrow involvement showed raised numbers of circulating hemopoietic progenitors. haematologica 2005; 90:976-977 (http:/

Analisi del campo di deformazione superficiale della Regione Campania da dati SAR (PS-InSAR)

Il lavoro presenta un’applicazione della tecnica dei diffusori permanenti (Permanent Scatterers) finalizzata alla caratterizzazione del campo di deformazione superficiale della Regione Campania. Per effettuare l’analisi sono state processate, tramite la tecnica PS-InSARTM, 1078 scene SAR ERS1 ed ERS2 relative al periodo giugno 1992 - gennaio 2001. Sulla base della velocità media annua di spostamento di 1.691.740 PS con coerenza maggiore di 0.65 sono state prodotte mappe di velocità media di deformazione mediante l’utilizzo di una procedura articolata nei seguenti punti: a) filtraggio dei dati effettuato sulla base dei valori di coerenza; b) produzione di mappe di velocità media di deformazione in coordinate SAR; c) generazione di mappe di velocità media di deformazione secondo le componenti verticale ed Est-Ovest; d) validazione di risultati mediante confronto con dati prodotti con differenti metodiche d’indagine. L’analisi dei risultati ottenuti ha consentito di identificare aree caratterizzate da distinti stili deformativi. Aree in subsidenza sono risultate essere, per il periodo di interesse, oltre all’area vulcanica dei Campi Flegrei, le aree costiere dei bacini dei fiumi Volturno e Sele ed il settore centrale dell’isola d’Ischia. Aree con significativi valori di sollevamento sono localizzate nel settore settentrionale del Monte Somma, nel settore centrale della Piana Campana, nel Sannio e nel Cilento. Significativi valori di velocità di spostamento in direzione EW si riscontrano, oltre che nell’area dei Campi Flegrei, nel settore appenninico del bacino del Sele e nell’area interposta tra il Somma-Vesuvio e la catena appenninica. Il quadro deformativo globale risulta essere caratterizzato da un andamento complesso, governato da una molteplicità di processi di differente natura (tettonici, vulcano-tettonici, esogeni ed antropici)

Energy Transmission by Barotropic Rossby Waves Revisited

This article presents a semianalytic method to investigate the properties of energy transmission across bottom topography by barotropic Rossby waves. The method is first used to revisit the analytical estimates derived from wave-matching techniques and Wentzel–Kramers–Brillouin (WKB) approximations. The comparison between the semianalytic method and WKB indicates that the results of the latter are valid for waves with periods longer than a month and ridges taller than ~1000 m and wider than ~500 km. For these parameter values both methods predict the passage of low-frequency waves and the reflection of high-frequency waves. The semianalytic method is then used to discuss the energy transmission properties of a cross section of the Mid-Atlantic Ridge. It is shown that the filtering characteristics of realistic bottom topographies depend not only on the spatial scale set by the cross-section envelope, but also on the scales of the individual peaks. This dependence is related to the fact that topographies narrower than ~400 km (e.g., peaks) are high-pass filters of incoming waves, while topographies wider than that (e.g., cross-section envelopes) are low-pass filters. In the particular case of the Mid-Atlantic Ridge the neglect of the contribution of individual peaks leads to an erroneous estimate of the filtering properties of the massif

Deglacial changes in flow and frontal structure through the Drake Passage

The oceanic gateways of the Drake Passage and the Agulhas Current are critical locations for the inflow of intermediate-depth water masses to the Atlantic, which contribute to the shallow return flow that balances the export of deep water from the North Atlantic. The thermohaline properties of northward flowing intermediate water are ultimately determined by the inflow of water through oceanic gateways. Here, we focus on the less well-studied “Cold Water Route” through the Drake Passage. We present millennially-resolved bottom current flow speed and sea surface temperature records downstream of the Drake Passage spanning the last 25,000 yr. We find that prior to 15 ka, bottom current flow speeds at sites in the Drake Passage region were dissimilar and there was a marked anti-phasing between sea surface temperatures at sites upstream and downstream of the Drake Passage. After 14 ka, we observe a remarkable convergence of flow speeds coupled with a sea surface temperature phase change at sites upstream and downstream of Drake Passage. We interpret this convergence as evidence for a significant southward shift of the sub-Antarctic Front from a position north of Drake Passage. This southward shift increased the through-flow of water from the Pacific, likely reducing the density of Atlantic Intermediate Water. The timing of the southward shift in the sub-Antarctic Front is synchronous with a major re-invigoration of Atlantic Meridional Overturning Circulation, with which, we argue, it may be linked

Prognostic role of amenorrhea induced by adjuvant chemotherapy in premenopausal patients with early breast cancer.

The prognostic role of drug-induced amenorrhea (DIA) was restrospectively evaluated in 221 out of 254 consecutive premenopausal patients treated with adjuvant CMF or a CMF-containing regimen; 33 patients were eliminated because of lack of menstrual data. All patients had metastatic axillary nodes; drug regimens were: CMF x 9 courses +/- Tamoxifen (TM) and CMF x 6 courses; median age was 43 (range 26-54). Premenopausal status was defined as last normal menses within the 6 weeks preceding initiation of chemotherapy: DIA as cessation of menses for at least 3 months not later than 3 months from the end of chemotherapy. DIA occurred in 166,221 (75.1%) patients and was strictly related to the age of the patients; also, the older the patients the shorter the time required to develop DIA. At median follow up of 69 months, Mantel-Byar analysis showed a longer disease free survival (DFS) for patients who developed DIA as compared with non amenorrheic women (P less than 0.001). DIA prognostic value was independent of age, number of involved nodes, tumour size and number of CMF cycles, as assessed by the Cox model (RH 0.43, 95% C.I. 0.24-0.77), in which DIA was entered as a time dependent covariate

Diffusive Spreading of Chainlike Molecules on Surfaces

We study the diffusion and submonolayer spreading of chainlike molecules on surfaces. Using the fluctuating bond model we extract the collective and tracer diffusion coefficients D_c and D_t with a variety of methods. We show that D_c(theta) has unusual behavior as a function of the coverage theta. It first increases but after a maximum goes to zero as theta go to one. We show that the increase is due to entropic repulsion that leads to steep density profiles for spreading droplets seen in experiments. We also develop an analytic model for D_c(theta) which agrees well with the simulations.Comment: 3 pages, RevTeX, 4 postscript figures, to appear in Phys. Rev. Letters (1996

Multimodal Treatment Eliminates Cancer Stem Cells and Leads to Long-Term Survival in Primary Human Pancreatic Cancer Tissue Xenografts.

Copyright: 2013 Hermann et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.PURPOSE: In spite of intense research efforts, pancreatic ductal adenocarcinoma remains one of the most deadly malignancies in the world. We and others have previously identified a subpopulation of pancreatic cancer stem cells within the tumor as a critical therapeutic target and additionally shown that the tumor stroma represents not only a restrictive barrier for successful drug delivery, but also serves as a paracrine niche for cancer stem cells. Therefore, we embarked on a large-scale investigation on the effects of combining chemotherapy, hedgehog pathway inhibition, and mTOR inhibition in a preclinical mouse model of pancreatic cancer. EXPERIMENTAL DESIGN: Prospective and randomized testing in a set of almost 200 subcutaneous and orthotopic implanted whole-tissue primary human tumor xenografts. RESULTS: The combined targeting of highly chemoresistant cancer stem cells as well as their more differentiated progenies, together with abrogation of the tumor microenvironment by targeting the stroma and enhancing tissue penetration of the chemotherapeutic agent translated into significantly prolonged survival in preclinical models of human pancreatic cancer. Most pronounced therapeutic effects were observed in gemcitabine-resistant patient-derived tumors. Intriguingly, the proposed triple therapy approach could be further enhanced by using a PEGylated formulation of gemcitabine, which significantly increased its bioavailability and tissue penetration, resulting in a further improved overall outcome. CONCLUSIONS: This multimodal therapeutic strategy should be further explored in the clinical setting as its success may eventually improve the poor prognosis of patients with pancreatic ductal adenocarcinoma