Nanostructured tin-carbon/ LiNi0.5Mn1.5O4 lithium-ion battery operating at low temperature

An advanced lithium ion battery using nanostructured tinecarbon lithium alloying anode and a high voltage LiNi0.5Mn1.5O4 spinel-type cathode is studied, with particular focus to the low temperature range. The stable behavior of the battery is assured by the use of an electrolyte media based on a LiPF6 salt dissolved in EC-DEC-DMC, i.e. a mixture particularly suitable for the low temperature application. Cycling tests, both in half cells and in full lithium ion battery using the SneC anode and the LiNi0.5Mn1.5O4 cathode, performed in a temperature range extending from room temperature to "30 C, indicate that the electrode/electrolyte configuration here adopted may be suitable for effective application in the lithium ion battery field. The full cell, cycled at -5 °C, shows stable capacity of about 105 mAh g-1 over more than 200 chargee-discharge cycles that is considered a relevant performance considering the low temperature region

GTP-bound Rab3A exhibits consecutive positive and negative roles during human sperm dense-core granule exocytosis

Exocytosis of mammalian sperm dense-core secretory granule relies on the same fusion molecules as all other secretory cells; one such molecule is the small GTPase Rab3A. Here, we report an in-depth biochemical characterization of the role of Rab3A in secretion by scrutinizing the exocytotic response of streptolysin O-permeabilized human sperm to the acute application of a number of Rab3A-containing constructs and correlating the findings with those gathered with the endogenous protein. Full length, geranylgeranylated, and active Rab3A elicited human sperm exocytosis per se. With Rab3A/Rab22A chimeric proteins, we demonstrated that the carboxy-terminal domain of the Rab3A molecule was necessary and sufficient to promote exocytosis, whereas its amino-terminus prevented calcium-triggered secretion. Interestingly, full length Rab3A halted secretion when added after the docking of the acrosome to the plasma membrane. This effect depended on the inability of Rab3A to hydrolyze GTP. We combined modified immunofluorescence and acrosomal staining protocols to detect membrane fusion and the activation status of endogenous Rab3 simultaneously in individual cells, and found that GTP hydrolysis on endogenous Rab3 was mandatory for fusion pores to open. Our findings contribute to establishing that Rab3 modulates regulated exocytosis differently depending on the nucleotide bound and the exocytosis stage under study.Fil: Bustos, Matias Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Roggero Savoini, Carlos Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. University of Texas; Estados UnidosFil: De la Iglesia, Paola X.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentina. Hospital Italiano; ArgentinaFil: Mayorga, Luis Segundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Tomes, Claudia Nora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Cienicas Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; Argentin

Mechanically milled, nanostructured Sn-C composite anode for lithium ion battery

A tin-carbon composite synthesized by high energy mechanical milling (HEMM) technique is characterized here as an anode material for lithium ion battery. The composite morphology and structure are studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD), respectively, and its electrochemical behavior is characterized by cyclic voltammetry (CV) and galvanostatic cycling in lithium cell. The electrode evidences highly nanostructured morphology and enhanced lithium-tin alloying-de-alloying process stability as the mechanical milling time is increased, with capacity ranging from 500 to 400 mAh g(-1). Further important characteristic of the tin-carbon nanostructure reported here is the very high rate capability, extending up to 2 A g(-1), that finally allows to its application in a high voltage, high rate lithium ion cell using the LiNi0.5Mn1.5O4 spinel cathode. The cell shows a working voltage of 4.3 V and a capacity of 120 mAh g(-1) obtained at 1 C rate. The very promising features of the cell, its high energy and power density, and the low cost of the involved materials, suggest that the electrode reported here can be efficiently used as an anode in advanced configuration lithium ion battery. (C) 2012 Elsevier Ltd. All rights reserved

Energy balance, leptin, NEFA and IGF-I plasma concentrations and resumption of post partum ovarian activity in Swedish Red And White breed cows

In the purpose to provide further information in respect of the relationship between metabolism and post partum (PP) ovarian activity resumption in dairy cows, the aim of the present study was to characterize the energy balance (EB) and leptin, NEFA and IGF-I plasma levels in Swedish Red and White (SRW) cows with and without ovarian activity re-initiation within 7 weeks PP. The study was conducted on 12 primiparous SRW cows fed the same diet as total mixed ration for ad libitum intake. The EB was calculated weekly from parturition until seven weeks PP. Blood samples were collected weekly from one week before until 7 weeks after calving for leptin, NEFA and IGF-I analysis. For progesterone (P4) analysis, blood samples were collected two times per week from parturition until the end of the study. P4 profile was used in addition to the clinical examination to detect cows with and without ovarian activity resumption. The clinical and ultrasonographic examination, coupled with P4 profile analysis showed the resumption of ovarian activity within 7 weeks after calving in 8 (group A) and no ovarian resumption in 4 cows (group B). No significant differences were detected in the whole period of observation in the amount of milk production between the two groups, while the mean milk protein content was significantly lower in group B at the third week PP. The calculated EB was negative in both groups in the first three weeks after calving, but more marked in group B. NEFA and Leptin plasma levels did not show significant differences between the two groups. In conclusion, the results of the present study showed that, when low milk producing primiparous cows are concerned, no significant differences in BW loss, milk yield, EB and leptin and NEFA plasma levels between the cows with and without resumption of ovarian activity within 7 weeks post partum were seen. However, significantly higher IGF-I levels in the first two weeks after calving were found in cows with post partum ovarian activity resumption, highlighting the important role of IGF-I as sensitive signal between metabolism and reproduction

Nanostructured tin-carbon/ LiNi0.5Mn1.5O4 lithium-ion battery operating at low temperature

An advanced lithium ion battery using nanostructured tinecarbon lithium alloying anode and a high voltage LiNi0.5Mn1.5O4 spinel-type cathode is studied, with particular focus to the low temperature range. The stable behavior of the battery is assured by the use of an electrolyte media based on a LiPF6 salt dissolved in EC-DEC-DMC, i.e. a mixture particularly suitable for the low temperature application. Cycling tests, both in half cells and in full lithium ion battery using the SneC anode and the LiNi0.5Mn1.5O4 cathode, performed in a temperature range extending from room temperature to "30 C, indicate that the electrode/electrolyte configuration here adopted may be suitable for effective application in the lithium ion battery field. The full cell, cycled at -5 °C, shows stable capacity of about 105 mAh g-1 over more than 200 chargee-discharge cycles that is considered a relevant performance considering the low temperature region

A Donor Polymer with a Good Compromise between Efficiency and Sustainability for Organic Solar Cells

Impressive advancements in solution‐processed bulk heterojunction (BHJ) solar cells have been driven to a large extent by the rational design of conjugated polymers as photoactive donors. These achievements have been obtained without paying much attention to green metrics parameters (such as E factor) and to the increasing synthetic complexity (SC), which is a bottleneck for industrial scalability. In this context, a novel donor copolymer (PBDT3T) based on benzodithiophene and terthiophene building blocks with ester functionalities is synthesized. The 26‐fold‐reduced E factor for the benzodithiophene monomer synthesis and the SC index of 24 for PBDT3T, much lower compared with benchmark donor polymers, provide a hint for good scalability, sustainability, and low costs. PBDT3T features a relatively wide optical bandgap and a deep highest occupied molecular orbital (HOMO), meeting the requirements for suitable donor material in both fullerene and nonfullerene‐based solar cells. PBDT3T is studied in binary and ternary blend, using PC71BM and ITIC as acceptors. The best performances are obtained in the ternary blend devices, reaching power conversion efficiency (PCE) values of 7.14%. Trade‐off considerations between PCE and SC make PBDT3T promising on an industrial perspective

Feed particle size evaluation: conventional approach versus digital holography based image analysis

The aim of this study was to evaluate the application of image analysis approach based on digital holography in defining particle size in comparison with the sieve shaker method (sieving method) as reference method. For this purpose ground corn meal was analyzed by a sieve shaker Retsch VS 1000 and by image analysis approach based on digital holography. Particle size from digital holography were compared with results obtained by screen (sieving) analysis for each of size classes by a cumulative distribution plot. Comparison between particle size values obtained by sieving method and image analysis indicated that values were comparable in term of particle size information, introducing a potential application for digital holography and image analysis in feed industry