50 research outputs found
Pd@TiO2/carbon nanohorn electrocatalysts: reversible CO2 hydrogenation to formic acid
Direct conversion of carbon dioxide to formic acid at thermodynamic equilibrium is an advantage of enzymatic catalysis, hardly replicated by synthetic analogs, but of high priority for carbon-neutral energy schemes. The bio-mimetic potential of totally inorganic Pd@TiO2 nanoparticles is envisioned herein in combination with Single Walled Carbon NanoHorns (SWCNHs). The high surface nano-carbon entanglement templates a wide distribution of \u201chard-soft\u201d bimetallic sites where the small Pd nanoparticles (1.5 nm) are shielded within the TiO2 phase (Pd@TiO2), while being electrically wired to the electrode by the nanocarbon support. This hybrid electrocatalyst activates CO2 reduction to formic acid at near zero overpotential in the aqueous phase (onset potential at E < 120.05 V vs. RHE, pH = 7.4), while being able to evolve hydrogen via sequential formic acid dehydrogenation. The net result hints at a unique CO2 \u201ccircular catalysis\u201d where formic acid versus H2 selectivity is addressable by flow-reactor technology
Convenient genotyping of nine bovine K-casein variants
K-casein gene polymorphisms are of major importance in the dairy
industry due to their association with different quality and productive
traits (i.e., milk protein). Several methods for genotyping this gene
have been proposed; however, none are focused on the simultaneous
discrimination of nine K-casein variants. A strategy based on PCR-RFLP
was designed to characterize nine K-casein variants (A, B, C, E, F2, G,
H, I and J) and used to genotype three cattle populations: Gyrholando
(3/8 Gyr x 5/8 Holstein), Charolais and Carora. The B variant was the
most frequent in the Charolais and Carora breeds, with allelic
frequencies of 0.60 and 0.59, respectively. In the Gyrholando breed,
four variants were found, with the A variant being the most frequent
and E and H the least. The genotyping strategy was effective in
detection and differentiation of K-casein variants, and it is proposed
for use in laboratories with minimal molecular biology equipment for
genotyping and evaluation of the phenotypic effects of nine K-casein
variants on milk production and quality
On the nature of defects in liquid-phase exfoliated graphene
Liquid-phase exfoliation is one of the most promising routes for large-scale production of multilayer graphene dispersions. These dispersions, which may be used in coatings, composites, or paints, are believed to contain disorder-free graphene multilayers. Here, we address the nature of defects in such samples obtained by liquid-phase exfoliation of graphite powder in N-methyl-2-pyrrolidone. Our Raman spectroscopy data challenge the assumption that these multilayers are free of bulk defects, revealing that defect localization strongly depends on the sonication time. For short ultrasound times, defects are located mainly at the layer edges but they turn out to build up in the bulk for ultrasonic times above 2 h. This knowledge may help to devise better strategies to achieve high-quality graphene dispersions.submittedVersionFil: Bracamonte, MarĂa Victoria. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Instituto de FĂsica Enrique Gaviola; Argentina.Fil: Bracamonte, MarĂa Victoria. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentina.Fil: Lacconi, Gabriela InĂŠs. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de FisicoquĂmica; Argentina.Fil: Lacconi, Gabriela InĂŠs. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Instituto de Investigaciones en FisicoquĂmica de CĂłrdoba; Argentina.Fil: Urreta, Silvia Elena. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Instituto de FĂsica Enrique Gaviola; Argentina.Fil: Urreta, Silvia Elena. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentina.Fil: Foa Torres, Luis Eduardo Francisco. Consejo Nacional de Investigaciones CientĂficas y TĂŠcnicas. Instituto de FĂsica Enrique Gaviola; Argentina.Fil: Foa Torres, Luis Eduardo Francisco. Universidad Nacional de CĂłrdoba. Facultad de MatemĂĄtica, AstronomĂa y FĂsica; Argentina.FĂsica de los Materiales Condensado
Loss of estrogen receptor β decreases mitochondrial energetic potential and increases thrombogenicity of platelets in aged female mice
Platelets derived from aged (reproductively senescent) female mice with genetic deletion of estrogen receptor beta (βER) are more thrombogenic than those from age-matched wild-type (WT) mice. Intracellular processes contributing to this increased thrombogenicity are not known. Experiments were designed to identify subcellular localization of estrogen receptors and evaluate both glycolytic and mitochondrial energetic processes which might affect platelet activation. Platelets and blood from aged (22â24 months) WT and estrogen receptor β knockout (βERKO) female mice were used in this study. Body, spleen weight, and serum concentrations of follicle-stimulating hormone and 17β-estradiol were comparable between WT and βERKO mice. Number of spontaneous deaths was greater in the βERKO colony (50% compared to 30% in WT) over the course of 24 months. In resting (nonactivated) platelets, estrogen receptors did not appear to colocalize with mitochondria by immunostaining. Lactate production and mitochondrial membrane potential of intact platelets were similar in both groups of mice. However, activities of NADH dehydrogenase, cytochrome bc1 complex, and cytochrome c oxidase of the electron transport chain were reduced in mitochondria isolated from platelets from βERKO compared to WT mice. There were a significantly higher number of phosphatidylserine-expressing platelet-derived microvesicles in the plasma and a greater thrombin-generating capacity in βERKO compared to WT mice. These results suggest that deficiencies in βER affect energy metabolism of platelets resulting in greater production of circulating thrombogenic microvesicles and could potentially explain increased predisposition to thromboembolism in some elderly females
Therapy Insight: Parenteral Estrogen treatment for Prostate Cancerâa new dawn for an old therapy
Oral estrogens were the treatment of choice for carcinoma of the prostate for over four decades, but were abandoned because of an excess of cardiovascular and thromboembolic toxicity. It is now recognized that most of this toxicity is related to the first pass portal circulation, which upregulates the hepatic metabolism of hormones, lipids and coagulation proteins. Most of this toxicity can be avoided by parenteral (intramuscular or transdermal) estrogen administration, which avoids hepatic enzyme induction. It also seems that a short-term but modest increase in cardiovascular morbidity (but not mortality) is compensated for by a long-term cardioprotective benefit, which accrues progressively as vascular remodeling develops over time. Parenteral estrogen therapy has the advantage of giving protection against the effects of andropause (similar to the female menopause), which are induced by conventional androgen suppression and include osteoporotic fracture, hot flashes, asthenia and cognitive dysfunction. In addition, parenteral estrogen therapy is significantly cheaper than contemporary endocrine therapy, with substantive economic implications for health providers
Track D Social Science, Human Rights and Political Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd
Molecular characterization of MHC class IIB genes of sympatric Neotropical cichlids
Ministerio de EconomĂa y Competitividad del Gobierno de EspaĂąa, Programa de FormaciĂłn de Personal Investigador FPI BES-2011-047645 to MJH, Programa Estatal de Fomento de la InvestigaciĂłn CientĂfica y TĂŠcnica de Excelencia Proyecto CGL 2010-16103 to MB. This project was further enabled through two German Science Foundation grants to CE (DFG, EI841/4-1 and EI841/6-1) both part of the SPP 1399 priority programme on âhost-parasite interactionsâ