Isotope effect on the E2g phonon and mesoscopic phase separation near the electronic topological transition in Mg1-xAlxB2

We report the boron isotope effect on the E2g phonon mode by micro-Raman spectroscopy on the ternary Mg1-xAlxB2 system, synthesized with pure isotopes 10B and 11B. The isotope coefficient on the phonon frequency is near 0.5 in the full range decreasing near x = 0. The intraband electron-phonon (e-ph) coupling, for the electrons in the sigma band, has been extracted from the E2g line-width and frequency softening. Tuning the Fermi energy near the electronic topological transition (ETT), where the sigma Fermi surface changes from 2D to 3D topology the E2g mode, shows the known Kohn anomaly on the 2D side of the ETT and a splitting of the E2g phonon frequency into a hard and soft component from x = 0 to x = 0.28. The results suggest a minor role of the intraband phonon mediated pairing in the control of the high critical temperature in Mg1-xAlxB2. The common physical features of diborides with the novel multigap FeAs-based superconductors and cuprates is discussed.Comment: 19 pages, 6 figure

Early-type Galaxies in the Hubble Deep Field. The <mu_e>-r_e relation and the lack of large galaxies at high redshift

We present the results of the detailed surface photometry of a sample of early-type galaxies in the Hubble Deep Field. Effective radii, surface brightnesses and total V_606 magnitudes have been obtained, as well as U_300, B_450, I_814, J, H and K colors, which are compared with the predictions of chemical-spectrophotometric models of population synthesis. Spectroscopic redshifts are available for 23 objects. For other 25 photometric redshifts are given. In the -r_e plane the early-type galaxies of the HDF, once the appropriate K+E corrections are applied, turn out to follow the `rest frame' Kormendy relation. This evidence, linked to the dynamical information gathered by Steidel et al.(1996), indicates that these galaxies, even at z~2-3, lie in the Fundamental Plane, in a virial equilibrium condition. At the same redshifts a statistically significant lack of large galaxies [i.e. with Log r_e(kpc) > 0.2] is observed.Comment: 30 pages, LaTeX with aasms4.sty macros, 9 embedded postscript figures + 1 postscript Table. To appear in the Astronomical Journa

IMAGINING CULTURES OF COOPERATION: UNIVERSITIES NETWORKING TO FACE THE NEW DEVELOPMENT CHALLENGES

The Proceedings of the CUCS Torino 2013 Congress (19-21 September 2013) represent the final step of a scientific project and of an organisational and relational process that have proved challenging, engaging and ultimately rewording. At the same time the Proceedings testify the growing contribution by the Italian universities to the debate on international development and set a new beginning towards the next CUCS Congress to be held in 2015 in Brescia, as well as towards a more tight and effective cooperation between Politecnico di Torino, University of Turin and all the other actors involved in international development cooperation within the territory of Turin and Piedmont (international organisations, local institutions, NGOs, foundations, private companies…)

Exact exchange-correlation potential for a time-dependent two electron system

We obtain an exact solution of the time-dependent Schroedinger equation for a two-electron system confined to a plane by an isotropic parabolic potential whose curvature is periodically modulated in time. From this solution we compute the exact time-dependent exchange correlation potential v_xc which enters the Kohn-Sham equation of time-dependent density functional theory. Our exact result provides a benchmark against which various approximate forms for v_xc can be compared. Finally v_xc is separated in an adiabatic and a pure dynamical part and it is shown that, for the particular system studied, the dynamical part is negligible.Comment: 23 pages, 6 figure

Heat Sensing Receptor TRPV1 Is a Mediator of Thermotaxis in Human Spermatozoa

The molecular bases of sperm thermotaxis, the temperature-oriented cell motility, are currently under investigation. Thermal perception relies on a subclass of the transient receptor potential [TRP] channels, whose member TRPV1 is acknowledged as the heat sensing receptor. Here we investigated the involvement of TRPV1 in human sperm thermotaxis. We obtained semen samples from 16 normozoospermic subjects attending an infertility survey programme, testis biopsies from 6 patients with testicular germ cell cancer and testis fine needle aspirates from 6 patients with obstructive azoospermia undergoing assisted reproductive technologies. Expression of TRPV1 mRNA was assessed by RT-PCR. Protein expression of TRPV1 was determined by western blot, flow cytometry and immunofluorescence. Sperm motility was assessed by Sperm Class Analyser. Acrosome reaction, apoptosis and intracellular-Ca2+ content were assessed by flow cytometry. We found that TRPV1 mRNA and protein were highly expressed in the testis, in both Sertoli cells and germ-line cells. Moreover, compared to no-gradient controls at 31°C or 37°C (Ctrl 31°C and Ctrl 37°C respectively), sperm migration towards a temperature gradient of 31-37°C (T gradient) in non-capacitated conditions selected a higher number of cells (14,9 ± 4,2×106 cells T gradient vs 5,1± 0,3×106 cells Ctrl 31°C and 5,71±0,74×106 cells Ctrl 37°C; P = 0,039). Capacitation amplified the migrating capability towards the T gradient. Sperms migrated towards the T gradient showed enriched levels of both TRPV1 protein and mRNA. In addition, sperm cells were able to migrate toward a gradient of capsaicin, a specific agonist of TRPV1, whilst capsazepine, a specific agonist of TRPV1, blocked this effect. Finally, capsazepine severely blunted migration towards T gradient without abolishing. These results suggest that TRPV1 may represent a facilitating mediator of sperm thermotaxis

A new sauropod titanosaur from the Plottier Formation (Upper Cretaceous) of Patagonia (Argentina)

This paper presents a new titanosaur sauropod, collected from levels of reddish clays assigned to the Plottier Formation (Coniacian-Santonian). The holotype of Petrobrasaurus puestohernandezi gen. et. sp. nov. is a disarticulated specimen, from which teeth, cervical, dorsal and caudal vertebrae, sternal plates, metacarpals, femora, tibia, a fragment of ilium, pubis, haemal arches, and cervical and dorsal ribs have been preserved. This period is of particular interest because it saw the definitive isolation of the vertebrate faunas of Patagonia, with the separation of South America from the rest of Gondwana, a process that had begun during the Early Cretaceous. Although some of the characters observed in Petrobrasaurus gen. nov. suggest a relationship with the South American clade Lognkosauria, this new sauropod is regarded as Titanosauria incertae sedis until a more profound analysis of the Titanosauria that in which it is included is undertaken

COCONUT LEAF WASTE PROCESSING WITH BIODRYING PROCESS AS RAW MATERIAL FOR BIOMASS PELLETS IN WASTE TO ENERGY

Coconut leaf waste is a type of waste that contains a good enough calorific value to be used as raw material for biomass pellets. The minimum standard calorific value of biomass in Indonesia according to SNI 8675:2018 is 16.05 MJ/kg. Meanwhile, based on the research results, the calorific value of coconut leaf waste has a value of 13.34 MJ/kg. The way that can be applied to increase the calorific value is by biodrying. This study aimed to determine the effectiveness of the biodrying process in processing coconut leaf waste. This study use bioactivators in the form of tempe yeast, baker's yeast, and tapai yeast. Mass loss and moisture reduction can be achieved, respectively, 8.25-17.62% and 62.4-65.6%. The calorific value can reach the minimum standard after seven days of processing with a value of 17,995-18,623 MJ/kg

Chirality effects on the IRMPD spectra of basket resorcinarene/nucleoside complexes

The IRMPD spectra of the ESI-formed proton-bound complexes of the R,R,R,R- and S,S,S,S-enantiomers of a bis(diamido)-bridged basket resorcin[4]arene (R and S) with cytosine (1), cytidine (2), and cytarabine (3) were measured in the region 2800– 3600 cm1. Comparison of the IRMPD spectra with the corresponding ONIOM (B3LYP/6-31(d):UFF)-calculated absorption frequencies allowed the assessment of the vibrational modes that are responsible for the observed spectroscopic features. All of the complexes investigated, apart from [R·H·3]+, showed similar IRMPD spectra, which points to similar structural and conformational landscapes. Their IRMPD spectra agree with the formation of several isomeric structures in the ESI source, wherein the N(3)-protonated guest establishes noncovalent interactions with the host amidocarbonyl groups that are either oriented inside the host cavity or outside it between one of the bridged side-chains and the upper aromatic nucleus. The IRMPD spectrum of the [R·H·3]+ complex was clearly different from the others. This difference is attributed to the effect of intramolecular hydrogen bonding interactions between the C(2’)-OH group and the aglycone oxygen atom of the nucleosidic guest upon repulsive interactions between the same oxygen atom and the aromatic rings of the host

Global-local plug-in for high-fidelity composite stress analysis in ABAQUS

This paper introduces a user-friendly tool for accurate stress prediction in laminate shell models in ABAQUS. The aim is to provide users with a code for the fast computation of three-dimensional solutions that overcome the limitations of classical shell models and facilitate the use of advanced composite failure criteria consistently. The methodology is based on a two-step global/local technique, denoted to as element-wise (EW), in which accurate local models with 3D capabilities stem from individual shell elements. The local analysis exploits refined laminated theories accounting for layer-wise deformations. Numerical examples on a typical aircraft structure serve as assessments to show the tool capabilities in handling various failure mode onsets., e.g., fiber breakage and matrix cracking