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The Natufian Culture and the Origin of the Neolithic in the Levant
Anthropolog
Preliminary hidrological results from Sarennes glacier basin, French Alps
Located in the French Alps, Glacier de Sarennes is a small glacier which has its mass balance, measured since 1948. Now since 1992, the Snow Engineenng and Avalanche control department of Cemagref Grenoble measures water leve1 in the emissary of this glacier at the altitude of 2800 meters. The time step of these records is 10 minutes. The aim of this study is to realize the first hydrological assessment, despite having few records until now, to be able to control the new experimental discharge station, and to extract the first scientific results
Preliminary hidrological results from Sarennes glacier basin, French Alps
Located in the French Alps, Glacier de Sarennes is a small glacier which has its mass balance, measured since 1948. Now since 1992, the Snow Engineenng and Avalanche control department of Cemagref Grenoble measures water leve1 in the emissary of this glacier at the altitude of 2800 meters. The time step of these records is 10 minutes. The aim of this study is to realize the first hydrological assessment, despite having few records until now, to be able to control the new experimental discharge station, and to extract the first scientific results
Five-level cascade asymmetric multilevel converter
A five-level cascaded asymmetric multilevel converter is analysed and designed. This topologysynthesises five voltage levels with a reduced number of components when compared to the most common symmetric topologies. It allows getting more voltage levels with less switching states. Its behaviour is similar to a hybrid converter with the advantage of working with only one DC bus. It does not present the usual drawbacks of symmetrical topologies. The cascaded asymmetric converter, presented here, appears as a very attractive alternative among the five-level converters with no voltage balancing problem. The performance of the proposed topology is evaluated with Pspice simulations in different applications.Fil: Gonzalez, Sergio Alberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de IngenierĂa; ArgentinaFil: Valla, Maria Ines. Universidad Nacional de La Plata. Facultad de IngenierĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - La Plata; ArgentinaFil: Christiansen, C. F.. Universidad Nacional de La Plata. Facultad de IngenierĂa; Argentin
Quasiparticle Liquid in the Highly Overdoped Bi2212
We present results from the study of a highly overdoped (OD) Bi2212 with a
K using high resolution angle-resolved photoemission spectroscopy.
The temperature dependent spectra near the () point show the presence of
the sharp peak well above . From the nodal direction, we make comparison
of the self-energy with the optimally doped and underdoped cuprates, and the
Mo(110) surface state. We show that this OD cuprate appears to have properties
that approach that of the Mo. Further analysis shows that the OD has a more
-independent lineshape at the Fermi surface than the lower-doped cuprates.
This allows for a realistic comparison of the nodal lifetime values to the
experimental resistivity measurements via Boltzmann transport formulation. All
these observations point to the validity of the quasiparticle picture for the
OD even in the normal state within a certain energy and momentum range.Comment: 4 pages, 4 figure
Sum rule for the optical scattering rates
An important quantity in electronic systems is the quasiparticle scattering
rate (QPSR). A related optical scattering rate (OSR) is routinely extracted
from optical data, and, while it is not the same as the QPSR, it nevertheless
displays many of the same features. We consider a sum rule which applies to the
area under a closely related quantity, almost equal to the OSR in the low
energy region. We focus on the readjustment caused by, for example, a
quasiparticle density of states change due to the superconducting transition.
Unfortunately, no general statement about mechanism can be made solely on the
energy scale in which the spectral weight readjustment on the OSR occurs.Comment: 22 pages, 7 figures accepted for publication by Phys. Rev.
Renormalization of spectral lineshape and dispersion below Tc in Bi2Sr2CaCu2O8+d
Angle-resolved photoemission (ARPES) data in the superconducting state of
Bi2Sr2CaCu2O8+d show a kink in the dispersion along the zone diagonal, which is
related via a Kramers-Kronig analysis to a drop in the low-energy scattering
rate. As one moves towards (pi,0), this kink evolves into a spectral dip. The
occurrence of these anomalies in the dispersion and lineshape throughout the
zone indicate the presence of a new energy scale in the superconducting state.Comment: New Figure 3 with expanded discussio
Review of outcomes used in nutritional trials in Pediatric Critical Care
Background: Generating robust evidence within Pediatric Intensive Care (PIC) can be challenging because of low patient numbers and patient heterogeneity. Systematic reviews may overcome small study biases but are limited by lack of standardisation in outcome measures and their definition. Trials of nutritional interventions in PIC are increasing, thus we wanted to examine the outcome measures being used in these trials.
Objective: To systematically describe outcome measures used when a nutritional intervention has been evaluated in a PIC randomized controlled trial.
Methods: A systematic literature review of all studies involving a PIC trial of a nutritional intervention was undertaken from 1 January 1996 until 20 February 2018.
Results: Thirty-one trials met the criteria and were reviewed. They included a total of 3346 patients across all trials. Thirty-nine primary outcomes and 93 secondary outcomes were found. These were categorized into PIC-related outcomes (infection, intensive care dependency, organ dysfunction / long-term functional and mortality) and nutritional outcomes (energy targets, nutritional parameters and feeding tolerance). We found large variation in the outcome measures used. Outcome domains of energy targets, feeding tolerance and infection were not adequately defined.
Conclusions: Large variations in the outcome measures chosen and their definitions exist within PIC nutritional trials. Optimal nutritional outcomes for PIC must be agreed and defined, specifically domains of nutrition efficiency, nutrition tolerance and non-nutritional PIC outcomes. The next step is to conduct an International Delphi study to gain expert consensus and develop a core outcome set to be reported in future pediatric nutrition trials
High-Resolution Photoemission Study of MgB2
We have performed high-resolution photoemission spectroscopy on MgB2 and
observed opening of a superconducting gap with a narrow coherent peak. We found
that the superconducting gap is s-like with the gap value of 4.5 meV at 15 K.
The temperature dependence (15 - 40 K) of gap value follows well the BCS form,
suggesting that 2Delta/kBTc at T=0 is about 3. No pseudogap behavior is
observed in the normal state. The present results strongly suggest that MgB2 is
categorized into a phonon-mediated BCS superconductor in the weak-coupling
regime.Comment: 3 pages, 3 figures, accepted in Physical Review Letter
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