Centennial-scale vegetation and North Atlantic Oscillation changes during the Late Holocene in the southern Iberia

High-reso CE to lution pollen analysis, charcoal, non-pollen palynomorphs and magnetic susceptibility have been analyzed in the sediment record of a peat bog in Sierra Nevada in southern Iberia. The study of these proxies provided the reconstruction of vegetation, climate, fire and human activity of the last ∼4500 cal yr BP. A progressive trend towards aridification during the late Holocene is observed in this record. This trend is interrupted by millennial- and centennial-scale variability of relatively more humid and arid periods. Arid conditions are recorded between ∼4000 and 3100 cal yr BP, being characterized by a decline in arboreal pollen and with a spike in magnetic susceptibility. This is followed by a relatively humid period from ∼3100 to 1600 cal yr BP, coinciding partially with the Iberian-Roman Humid Period, and is indicated by the increase of Pinus and the decrease in xerophytic taxa. The last 1500 cal yr BP are characterized by several centennial-scale climatic oscillations. Generally arid conditions from ∼450 to 1300 CE, depicted by a decrease in Pinus and an increase in Artemisia, comprise the Dark Ages and the Medieval Climate Anomaly. Since ∼ 1300 to 1850 CE pronounced oscillations occur between relatively humid and arid conditions. Four periods depicted by relatively higher Pinus coinciding with the beginning and end of the Little Ice Age are interrupted by three arid events characterized by an increase in Artemisia. These alternating arid and humid shifts could be explained by centennial-scale changes in the North Atlantic Oscillation and solar activity

An overview on armor research for the laser fusion project HiPER

During the current preparatory phase of the European laser fusion project HiPER, an intensive effort has being placed to identify an armour material able to protect the internal walls of the chamber against the high thermal loads and high fluxes of x-rays and ions produced during the fusion explosions. This poster addresses the different threats and limitations of a poly-crystalline Tungsten armour. The analysis is carried out under the conditions of an experimental chamber hypothetically constructed to demonstrate laser fusion in a repetitive mode, subjected to a few thousand 48MJ shock ignition shots during its entire lifetime. If compared to the literature, an extrapolation of the thermomechanical and atomistic effects obtained from the simulations of the experimental chamber to the conditions of a Demo reactor (working 24/7 at hundreds of MW) or a future power plant (producing GW) suggests that “standard” tungsten will not be a suitable armour. Thus, new materials based on nano-structured W and C are being investigated as possible candidates. The research programme launched by the HiPER material team is introduced

Light and Life: Exotic Photosynthesis in Binary Star Systems

The potential for hosting photosynthetic life on Earth-like planets within binary/multiple stellar systems was evaluated by modelling the levels of photosynthetically active radiation (PAR) such planets receive. Combinations of M and G stars in: (i) close-binary systems; (ii) wide-binary systems and (iii) three-star systems were investigated and a range of stable radiation environments found to be possible. These environmental conditions allow for the possibility of familiar, but also more exotic forms of photosynthetic life, such as infrared photosynthesisers and organisms specialised for specific spectral niches.Comment: Accepted for publication in: Astrobiolog

Tumor necrosis factor reduces Plasmodium falciparum growth and activates calcium signaling in human malaria parasites

Background: Plasmodium has a complex biology including the ability to interact with host signals modulating their function through cellular machinery. Tumor necrosis factor (TNF) elicits diverse cellular responses including effects in malarial pathology and increased infected erythrocyte cytoadherence. As TNF levels are raised during P. falciparum infection we have investigated whether it has an effect on the parasite asexual stage. Methods: Flow cytometry, spectrofluorimetric determinations, confocal microscopy and PCR real time quantifications were employed for characterizing TNF induced effects and membrane integrity verified by wheat germ agglutinin staining. Results: TNF is able to decrease intracellular parasitemia, involving calcium as a second messenger of the pathway. Parasites incubated for 48h with TNF showed reduced erythrocyte invasion. Thus, TNF induced rises in intracellular calcium concentration, which were blocked by prior addition of the purinergic receptor agonists KN62 and A438079, or interfering with intra- or extracellular calcium release by thapsigargin or EGTA (ethylene glycol tetraacetic acid). Importantly, expression of PfPCNA1 which encodes the Plasmodium falciparum Proliferating-Cell Nuclear Antigen 1, decreased after P. falciparum treatment of TNF (tumor necrosis factor) or 6-Bnz cAMP (N6-Benzoyladenosine-3′,5′-cyclic monophosphate sodium salt). Conclusions: This is potentially interesting data showing the relevance of calcium in down regulating a gene involved in cellular proliferation, triggered by TNF. General significance: The data show that Plasmodium may subvert the immunological system and use TNF for the control of its proliferation within the vertebrate host

Effects of macrosegregation and microstructure on the corrosion resistance and hardness of a directionally solidified Zn-5.0wt.%Mg alloy

This study aims to analyze the influence of macrosegregation on microstructure evolution, and of microstructure length scale on the corrosion resistance of a Zn-5.0wt.%Mg alloy casting. The analyzed samples were taken along the length of castings unidirectionally solidified in unsteady state conditions of heat extraction. Microstructure characterization, microhardness, linear polarization and electrochemical impedance spectroscopy (EIS) tests were performed. A unique type of microstructure was observed, characterized essentially by a morphology typified by idiomorphic MgZn2 crystals in a “complex eutectic mixture” [coexistence of stable (Zn+Mg2Zn11) and metastable (Zn+MgZn2) eutectics]. The correlation between thermal and microstructural parameters, permitted experimental growth laws, correlating the evolution of the lamellar eutectic spacing with the cooling rate to be established. Vickers microhardness and electrochemical corrosion tests showed that more refined microstructures associated with higher experimental cooling rates, are related to a better set of higher hardness and corrosion resistance221CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP155863/2013-4; Project i-link0944; 166912/2017-4não tem2012/08494-0; 2013/15478-3; 2013/25452-1; 2013/23396-7; 2014/50502-

Calcium signaling in a low calcium environment: how the intracellular malaria parasite solves the problem

Malaria parasites, Plasmodia, spend most of their asexual life cycle within red blood cells, where they proliferate and mature. The erythrocyte cytoplasm has very low [Ca2+] (<100 nM), which is very different from the extracellular environment encountered by most eukaryotic cells. The absence of extracellular Ca2+ is usually incompatible with normal cell functions and survival. In the present work, we have tested the possibility that Plasmodia overcome the limitation posed by the erythrocyte intracellular environment through the maintenance of a high [Ca2+] within the parasitophorous vacuole (PV), the compartment formed during invasion and within which the parasites grow and divide. Thus, Plasmodia were allowed to invade erythrocytes in the presence of Ca2+ indicator dyes. This allowed selective loading of the Ca2+ probes within the PV. The [Ca2+] within this compartment was found to be ∼40 μM, i.e., high enough to be compatible with a normal loading of the Plasmodia intracellular Ca2+ stores, a prerequisite for the use of a Ca2+-based signaling mechanism. We also show that reduction of extracellular [Ca2+] results in a slow depletion of the [Ca2+] within the PV. A transient drop of [Ca2+] in the PV for a period as short as 2 h affects the maturation process of the parasites within the erythrocytes, with a major reduction 48 h later in the percentage of schizonts, the form that re-invades the red blood cells

Cyclic AMP and calcium interplay as second messengers in melatonin-dependent regulation of Plasmodium falciparum cell cycle

The host hormone melatonin increases cytoplasmic Ca2+ concentration and synchronizes Plasmodium cell cycle (Hotta, C.T., M.L. Gazarini, F.H. Beraldo, F.P. Varotti, C. Lopes, R.P. Markus, T. Pozzan, and C.R. Garcia. 2000. Nat. Cell Biol. 2:466–468). Here we show that in Plasmodium falciparum melatonin induces an increase in cyclic AMP (cAMP) levels and cAMP-dependent protein kinase (PKA) activity (40 and 50%, respectively)

A Bovine Pericardium Rigid Prosthesis For Left Ventricle Restoration: 12 Years Of Follow-up [prótese Rígida De Pericárdio Bovino Para Remodelamento Ventricular Esquerdo: 12 Anos De Seguimento]

Background: Myocardial infarction might result in dilated left ventricle and numerous techniques have been described to restore the original left ventricle shape and identify tools for late survival assessment. The aim of this study is to compare our experience with a modified Dor procedure using a rigid prosthesis to the septal anterior ventricular exclusion procedure (SAVE) for left ventricle restoration. The EuroScore index for prediction of late follow up survival was evaluated. Methods: We evaluated 80 patients who underwent left ventricle restoration between 1999 to 2007 and eight patients were excluded with incomplete data. A modified Dor procedure with rigid prosthesis (MD group) was performed on 53 patients and 19 underwent the septal anterior ventricular exclusion procedure (SAVE group). The patients were classified according their left ventricle shape as type I, II or III. Kaplan-Meier and Cox proportional hazard ratio regressions analysis were performed to assess survival after both techniques and expected surgical mortality using EuroScore index ranking after 12 years of follow up. Results: The operative mortality was comparable in both groups ranked by EuroScore index. The groups were comparable for all clinical data, except the MD group had more patients using intra-aortic balloon pumps before surgery, (5.7% vs. 0; P<0.01). Kaplan Meier analysis by left ventricle shape showed comparable survival for all patients, with slightly higher survival for type I. Kaplan Meier analysis of all death showed equivalent survival curves for both techniques after 12 years of follow up (71.5 ± 12.3 vs. 46.6 ±20.5 years; P=0.08). Kaplan Meier analysis of EuroScore index for all patients showed a difference between the three ranked categories, i.e., 0 to 10%, 11 to 49% and higher than 50% expected surgical mortality after 12 years of follow up (70.9 ± 16.2 vs. 67.5 ± 12.7 vs. 53.0 ± 15.5; P=0.003). Conclusion: The MD procedure showed consistent ejection fraction improvements after long term follow up. Survival was comparable for all ventricular types and for the MD and SAVE procedures. The EuroScore index is a useful index for late survival assessment of ventricular restoration techniques.262164172Cooley, D.A., Hallman, G.L., Henly, W.S., Left ventricular aneurysm due to myocardial infarctionexperience with 37 patients undergoing aneurysmectomy (1964) Arch Surg, 88, pp. 114-121Jatene, A.D., Left ventricular aneurysmectomy. Resection or reconstruction (1985) J Thorac Cardiovasc Surg, 89 (3), pp. 321-331Dor, V., Saab, M., Coste, P., Kornaszewska, M., Montiglio, F., Left ventricular aneurysm: A new surgical approach (1989) Thorac Cardiovasc Surg, 37 (1), pp. 11-19Dor, V., Sabatier, M., di Donato, M., Montiglio, F., Toso, A., Maioli, M., Efficacy of endoventricular patch plasty in large postinfarction akinetic scar and severe left ventricular dysfunction: Comparison with a series of large dyskinetic scars (1998) J Thorac Cardiovasc Surg, 116 (1), pp. 50-59Braile, D.M., Mustafa, R.M., Ardito, R.V., Zaiantchick, M., Coelho, W.M., (1991) Correction of the Left Ventricle Geometry with Semi Rigid Bovine Pericardial Prosthesis Rev Bras Cir Cardiovasc, 6 (2), pp. 109-115Isomura, T., Horii, T., Suma, H., Buckberg, G.D., Septal anterior ventricular exclusion operation (Pacopexy) for ischemic dilated cardiomyopathy: Treat form not disease (2006) Eur J Cardiothorac Surg, 29 (SUPPL. 1), pp. S245-S250. , RESTORE GroupJones, R.H., Velazquez, E.J., Michler, R.E., Sopko, G., Oh, J.K., O'Connor, C.M., Coronary bypass surgery with or without surgical ventricular reconstruction (2009) N Engl J Med, 360 (17), pp. 1705-1717di Donato, M., Castelvecchio, S., Kukulski, T., Bussadori, C., Giacomazzi, F., Frigiola, A., Surgical ventricular restoration: Left ventricular shape influence on cardiac function, clinical status, and survival (2009) Ann Thorac Surg, 87 (2), pp. 455-461Najafi, M., Sheikhvatan, M., Montazeri, A., Sheikhfathollahi, M., Predictors of quality of life among patients undergoing coronary artery bypass surgery (2008) Acta Cardiol, 63 (6), pp. 713-721Messaoudi, N., de Cocker, J., Stockman, B.A., Bossaert, L.L., Rodrigus, I.E., Is EuroSCORE useful in the prediction of extended intensive care unit stay after cardiac surgery? (2009) Eur J Cardiothorac Surg, 36 (1), pp. 35-39Santarpino, G., Onorati, F., Rubino, A.S., Abdalla, K., Caroleo, S., Santangelo, E., Preoperative intraaortic balloon pumping improves outcomes for high-risk patients in routine coronary artery bypass graft surgery (2009) Ann Thorac Surg, 87 (2), pp. 481-488Nashef, S.A., Roques, F., Michel, P., Gauducheau, E., Lemeshow, S., Salamon, R., European system for cardiac operative risk evaluation (EuroSCORE) (1999) Eur J Cardiothorac Surg, 16 (1), pp. 9-13Dor, V., Sabatier, M., di Donato, M., Maioli, M., Toso, A., Montiglio, F., Late hemodynamic results after left ventricular patch repair associated with coronary grafting in patients with postinfarction akinetic or dyskinetic aneurysm of the left ventricle (1995) J Thorac Cardiovasc Surg, 110 (5), pp. 1291-1299Athanasuleas, C.L., Buckberg, G.D., Stanley, A.W., Siler, W., Dor, V., Didonato, M., RESTORE Group. Surgical ventricular restoration: The RESTORE Group experience (2004) Heart Fail Rev, 9 (4), pp. 287-297Salati, M., di Biasi, P., Paje, A., Santoli, C., Left ventricular geometry after endoventriculoplasty (1993) Eur J Cardiothorac Surg, 7 (11), pp. 574-578Buckberg, G.D., Coghlan, H.C., Torrent-Guasp, F., The structure and function of the helical heart and its buttress wrapping. VI. Geometric Concepts of Heart Failure and Use For Structural Correction (2001) Semin Thorac Cardiovasc Surg, 13 (4), pp. 386-401di Donato, M., Sabatier, M., Dor, V., Gensini, G.F., Toso, A., Maioli, M., Effects of the Dor procedure on left ventricular dimension and shape and geometric correlates of mitral regurgitation one year after surgery (2001) J Thorac Cardiovasc Surg, 121 (1), pp. 91-96Suma, H., Horii, T., Isomura, T., Buckberg, G., A new concept of ventricular restoration for nonischemic dilated cardiomyopathy (2006) Eur J Cardiothorac Surg, 29 (SUPPL. 1), pp. S207-S212. , RESTORE GroupForm versus disease: Optimizing geometry during ventricular restoration (2006) Eur J Cardiothorac Surg, 29 (SUPPL. 1), pp. S238-S244. , RESTORE GroupKieser, T.M., The left ventricle: To reconstruct or not: Lessons from the STICH trial (2009) J Thorac Cardiovasc Surg, 138 (3), p. 784Suma, H., Isomura, T., Horii, T., Buckberg, G., Role of site selection for left ventriculoplasty to treat idiopathic dilated cardiomyopathy (2004) Heart Fail Rev, 9 (4), pp. 329-336. , RESTORE GroupDancini, J.L., Rodrigues, J.J., Santos, J.S., Pinto, R.F.A., Burgos, F.J.C., Conforti, C.A., Left ventricular aneurysmectomy: Late followup (1996) Rev Bras Cir Cardiovasc, 1 (11), pp. 23-29Almeida, R.M.S., Lima, J.D., Bastos, L.C., Carvalho, C.T., Loures, D.R., Endoventricular circular patch plasty with septal exclusion: Initial experience (2000) Rev Bras Cir Cardiovasc, 4 (15), pp. 302-307Campagnucci, V.P., Rivetti, L.A., Pinto e Silva, A.M.R., Gandra, S.M.A., Pereira, W.L., Aneurismectomia de ventrículo esquerdo com o coração batendo ininterruptamente: Resultados imediatos (2006) Rev Bras Cir Cardiovasc, 21 (1), pp. 55-61Herrera, C.B., Insalralde, A., Brandi, A.C., Santos, C.A., Herrera, D.D., Soares, M.J.F., Correção de aneurisma de ventrículo esquerdo em paciente chagásico empregando prótese de pericárdio bovino (2000) Rev Bras Cir Cardiovasc, 15 (1), pp. 72-74Sgarbi, C.J., Ardito, R.V., Santos, R.C., Bogdan, R.A.B., Arruda Jr., F.V., Silva, E.M., Correção cirúrgica do aneurisma de ventrículo esquerdo: Comparação entre as técnicas de sutura linear e reconstrução geométrica (2000) Rev Bras Cir Cardiovasc, 15 (4), pp. 293-301Versteegh, M.I., Lamb, H.J., Bax, J.J., Curiel, F.B., van der Wall, E.E., de Roos, A., MRI evaluation of left ventricular function in anterior LV aneurysms before and after surgical resection (2003) Eur J Cardiothorac Surg, 23 (4), pp. 609-613Use of cardiac magnetic resonance imaging in surgical ventricular restoration (2006) Eur J Cardiothorac Surg, 29 (SUPPL. 1), pp. S216-S224. , Buckberg GD;RESTORE GroupWalker, J.C., Guccione, J.M., Jiang, Y., Zhang, P., Wallace, A.W., Hsu, E.W., Helical myofiber orientation after myocardial infarction and left ventricular surgical restoration in sheep (2005) J Thorac Cardiovasc Surg, 129 (2), pp. 382-39

Probing Non-Standard Couplings of Neutrinos at the Borexino Detector

The present experimental status does not exclude weak-strength non-standard interactions of neutrinos with electrons. These interactions can be revealed in solar neutrino experiments. Our discussion covers several aspects related to this issue. First, we perform an analysis of the Super Kamiokande and SNO data to investigate their sensitivity to such interactions. In particular, we show that the \nu_e oscillation into sterile neutrinos can be still allowed if \nu_e has extra interactions of the proper strength. Second, we suggest that the Borexino detector can provide good signatures for these non-standard interactions. Indeed, in Borexino the shape of the recoil electron spectrum from the \nu e \to \nu e scattering essentially does not depend on the solar neutrino conversion details, since most of the signal comes from the mono-energetic ^7Be neutrinos. Hence, the partial conversion of solar \nu_e into a a nearly equal mixture of \nu_\mu and \nu_\tau, as is indicated by the atmospheric neutrino data, offers the chance to test extra interactions of \nu_\tau, or of \nu_e itself.Comment: 17 LaTeX pages, 15 postscript figures, uses epsfig.sty. More extended discussion about the spectral deformation for both Super-Kamiokande and Borexino; new figures are adde

Robust signatures of solar neutrino oscillation solutions

With the goal of identifying signatures that select specific neutrino oscillation parameters, we test the robustness of global oscillation solutions that fit all the available solar and reactor experimental data. We use three global analysis strategies previously applied by different authors and also determine the sensitivity of the oscillation solutions to the critical nuclear fusion cross section, S_{17}(0), for the production of 8B. The favored solutions are LMA, LOW, and VAC in order of g.o.f. The neutral current to charged current ratio for SNO is predicted to be 3.5 +- 0.6 (1 sigma), which is separated from the no-oscillation value of 1.0 by much more than the expected experimental error. The predicted range of the day-night difference in charged current rates is (8.2 +- 5.2)% and is strongly correlated with the day-night effect for neutrino-electron scattering. A measurement by SNO of either a NC to CC ratio > 3.3 or a day-night difference > 10%, would favor a small region of the currently allowed LMA neutrino parameter space. The global oscillation solutions predict a 7Be neutrino-electron scattering rate in BOREXINO and KamLAND in the range 0.66 +- 0.04 of the BP00 standard solar model rate, a prediction which can be used to test both the solar model and the neutrino oscillation theory. Only the LOW solution predicts a large day-night effect(< 42%) in BOREXINO and KamLAND. For the KamLAND reactor experiment, the LMA solution predicts 0.44 of the standard model rate; we evaluate 1 sigma and 3 sigma uncertainties and the first and second moments of the energy spectrum.Comment: Included predictions for KamLAND reactor experiment and updated to include 1496 days of Super-Kamiokande observation