953 resultados para Oh(•)
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The reaction of [Re6Q8(OH)6]4- (Q = S, Se) with p-tertbutylpyridine (TBP) in water leads to neutral trans-[Re6Q8(TBP)4(OH)2] whose hydroxyl reactivity with carboxylic acid and TBP exchange reaction with functional pyridine have been investigated.
Increasing the electrolyte capacity of alkaline Zn-air fuel cells by scavenging zincate with Ca(OH)2
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The use of calcium hydroxide for scavenging zincate species is demonstrated to be a highly effective approach for increasing the electrolyte capacity and improving the performance of the zinc-air fuel cell system. A fundamental approach is established in this study to quantify the formation of calcium zincate as the product of scavenging and the amount of water compensation necessary for optimal performance. The good agreement between predicted and experimental results proves the validity of the proposed theoretical approach. By applying the results of theoretical predictions, both the electrolyte capacity and the cell longevity have been increased by more than 40%. It is also found that, using Ca(OH)
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Here we present the design and fabrication of multi-notch optical fibre Bragg gratings for suppressing OH emission lines in the near infrared spectra of the night sky for astrophysical applications. We demonstrate a novel approach of fabricating 2, 3 and 5-notch filters using the phase mask technology, which show a good match with the model.
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This flyer promotes the event " ¡Oh Cuba Hermosa! El cancionero político social en Cuba hasta 1958, Book presentation by Cristóbal Díaz Ayala" cosponsored by FIU Libraries. This event was held at Books & Books in Coral Gables.
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The aim of this study was to examine the plasma concentrations and prevalence of polychlorinated biphenyls (PCBs) and hydroxylated PCB-metabolites (OH-PCBs) in polar bear (Ursus maritimus) mothers (n = 26) and their 4 months old cubs-of-the-year (n = 38) from Svalbard to gain insight into the mother-cub transfer, biotransformation and to evaluate the health risk associated with the exposure to these contaminants. As samplings were performed in 1997/1998 and 2008, we further investigated the differences in levels and pattern of PCBs between the two sampling years. The plasma concentrations of Sum(21)PCBs (1997/1998: 5710 ± 3090 ng/g lipid weight [lw], 2008: 2560±1500 ng/g lw) and Sum(6)OH-PCBs (1997/1998: 228 ± 60 ng/g wet weight [ww], 2008: 80 ± 38 ng/g ww) in mothers were significantly lower in 2008 compared to in 1997/1998. In cubs, the plasma concentrations of Sum(21)PCBs (1997/1998: 14680 ± 5350 ng/g lw, 2008: 6070 ± 2590 ng/g lw) and Sum(6)OH-PCBs (1997/1998: 98 ± 23 ng/g ww, 2008: 49 ± 21 ng/g ww) were also significantly lower in 2008 than in 1997/1998. Sum(21)PCBs in cubs was 2.7 ± 0.7 times higher than in their mothers. This is due to a significant maternal transfer of these contaminants. In contrast, Sum(6)OH-PCBs in cubs were approximately 0.53 ± 0.16 times the concentration in their mothers. This indicates a lower maternal transfer of OH-PCBs compared to PCBs. The majority of the metabolite/precursor-ratios were lower in cubs compared to mothers. This may indicate that cubs have a lower endogenous capacity to biotransform PCBs to OH-PCBs than polar bear mothers. Exposure to PCBs and OH-PCBs is a potential health risk for polar bears, and the levels of PCBs and OH-PCBs in cubs from 2008 were still above levels associated with health effects in humans and wildlife.
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Cadwaladerite (Al(OH)2Cl∙4H2O) collected from Cerro Pintados, Chile described by Gordon in 1941 is designated as “doubtful” by the IMA. Material collected from the same locality in 2015 resembling the description of cadwaladerite gave a powder XRD pattern similar to lesukite (Al2(OH)5Cl∙2H2O). However, Gordon provided no X-ray data for his material from Cerro Pintados. In order to determine whether cadwaladerite and lesukite are the same mineral species, measurements were made on a suite of samples from various localities. A portion of the material collected by Gordon in 1941 was also obtained from the Mineralogical Museum of Harvard University. Type material of lesukite from a fumarolic environment at the Tolbachik Fissure in Kamchatka, Russia was obtained as well as lesukite from the Maria Mine, Chile (Arica Province) and a previously undescribed locality for lesukite (Barranaca del Sulfato, Mejillones Peninsula, Antofagasta Province). All samples are yellow to yellow-orange in colour and all exhibit small cubic crystals (up to 50µm), even Gordon’s cadwaladerite which was thought to be amorphous. The Chilean samples are all associated with halite and sometimes with anhydrite. These five samples were studied by SEM, FTIR, powder XRD, and Raman spectroscopy. A ratio of Al:Cl less than or equal to 1.3:1 was observed for all the samples, including measurements made on lesukite from the Russian locality Vergasova et al. studied in 1997, and determined to have a 2:1 ratio. SEM-EDS analyses also show all samples to have minor iron substitution, as well as copper substitution in two samples. FTIR spectra are very similar for all samples. Raman spectroscopy done on both samples collected in Cerro Pintados and the Russian lesukite gave similar spectra. Powder XRD analyses on all samples showed spectra identified to be lesukite, including Gordon’s cadwaladerite. Crystal cell parameters calculated from powder XRD ranged from 19.778Å to 19.878Å. Results using modern instrumental techniques confirm Gordon’s cadwaladerite, collected in 1939 and described in 1941, and lesukite are the same mineral species.
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info:eu-repo/semantics/published
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The basic copper(II) carboxylate adduct, [Cu2-OH(O 2CCF3)3(quinoline)2]2, has been shown by an X-ray structural analysis to have a novel tetranuclear structure; magnetic susceptibility data show that substantial Cu-Cu interaction is present in this compound.
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Fondo Margaritainés Restrepo
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Galanin and Galanin (1-15) [GAL(1-15)] are implicated in anxiety- and depression related behaviors. Moreover, Galanin modulates 5-HT1A receptor (5-HT1AR) function at autorreceptor and postsynaptic level in the brain. In this study, we have analysed the ability of GAL(1-15) to modulate the effects of the 8-OH-DPAT agonist in the Forced Swimming Test (FST). Groups of rats were assessed in the FST. In the first set of experiments, to evaluate the interactions of 8-OH-DPAT and GAL(1-15), rats received subcutaneously (s.c) the effective doses of 8-OH-DPAT (0.25mg/Kg) 60min before the test and intracerebroventricularly (icv) GAL(1-15)1nmol 15min before the tests alone or in combination. In the second set of experiments, groups of rats received s.c. 8-OH-DPAT (0.125mg/Kg), icv GAL(1-15) 1nmol and icv the GALR2 antagonist M871 3 nmol alone or in combination. The locomotor activity was analysed in the open field test. GAL(1-15) 1nmol enhanced the antidepressant-like effects mediated by the effective dose of the 8-OH-DPAT. GAL(1-15) significantly decreased the immobility (p<0.05) and climbing (p<0.05) and increased the swimming (p<0.01) behaviour induced by an effective dose of 8-OH-DPAT (0.25mg/Kg) in FST. Moreover, after coadministration of GAL(1-15) and threshold dose of 8-OH-DPAT (0.125mg/Kg) a significant decreased appeared in immobility (p<0.01) and climbing (p<0.01) and increased the swimming behavior (p<0.001) vs 8-OH-DPAT group. Moreover, M871 blocked completely this interaction. These results indicate that GAL(1-15) enhances the antidepressant effects induced by 8-OH-DPAT in the FST. These findings may give the basis for the development of novel therapeutic drugs. This study was supported by Junta de Andalucía CVI6476.
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We have described that Galanin N-terminal fragment (1-15) [GAL(1-15)] is associated with depressive effects and also modulates the antidepressant effects induced by the 5-HT1A receptor (5-HT1AR) agonist 8-OH-DPAT. The aim of this study is to analyze the ability of GAL(1-15) to modulate 5-HT1AR at the autoreceptor and postsynaptic receptor level in rats by using quantitative autoradiography. We analyzed the effect of intracerebroventricular GAL(1-15)-3nmol (n=6) or aCSF (n=6), 10 minutes, 2 and 5 hours after the injection, on the binding characteristics of the 5-HT1AR agonist [H3]-8-OH-DPAT in sections of the Dorsal Raphe (DR) and Dorsal Hippocampus, specifically CA1 and Dentate Gyrus (DG). Student’s t-test was used to compare the experimental groups. GAL(1-15) produced a time-dependent effect on the binding of [H3]-8-OH-DPAT. In CA1 and DG, a significant increase in the KD and Bmax was observed, by 90%(p<0.05), at 10 minutes and 2 hours after injection. However, 5 hours after GAL(1-15) the only significant change remaining was the increase in Bmax at the DG. The coinjection of the GALR2 antagonist M871 blocked significantly the effects induced by GAL(1-15) in both areas. In DR, 2 hours after injection GAL(1-15) only produced a decrease in the Bmax by 20%(p<0.05). These results indicate that GAL(1-15) interacts with 5-HT1AR at the receptor level in DR and Dorsal Hippocampus. Therapeutic strategies based on these results could be developed for the treatment of depression disorders. This work has been supported by Junta de Andalucia CVI646 and Spanish Ministry of Economy PSI2013-44901-P.
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A corrosion product rarely reported in the literature has been found on the copper support of three miniature paintings of the 17th and 18th centuries. This product, which has been identified as dicoppertrihydroxyformate (Cu2(OH)3HCOO), is an unusual basic copper formate found on copper artifacts. The identification and characterization of dicoppertrihydroxyformate was carried out directly over the corroded surface of the objects, using a nondestructive approach, which combines the integrated use of various microanalytical techniques. Using this approach, it was possible to obtain a set of new reference data about the natural form of Cu2(OH)3HCOO, that will enable its unambiguous identification in other similar objects. In this work, the probable causes that may have contributed to its formation are also discussed.
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The Authors describe first-hand experiences carried out within the framework of selected International projects aimed at developing collaborative research and education using the One Health (OH) approach. Special emphasis is given to SAPUVETNET, a series of projects co-financed under the EU-ALFA program, and aimed to support an International network on Veterinary Public Health (VPH) formed by Veterinary Faculties from Latin-America (LA) and Europe (EU). SAPUVETNET has envisaged a series of objectives/activities aimed at promoting and enhancing VPH research/training and intersectoral collaboration across LA and EU using the OH approach, as well as participating in research and/or education projects/networks under the OH umbrella, namely EURNEGVEC-European Network for Neglected Vectors & Vector-Borne Infections, CYSTINET-European Network on Taeniosis/Cysticercosis, and NEOH-Network for Evaluation of One Health; the latter includes expertise in multiple disciplines (e.g. ecology, economics, human and animal health, epidemiology, social and environmental sciences, etc.) and has the primary purpose of enabling quantitative evaluation of OH initiatives by developing a standardized evaluation protocol. The Authors give also an account of the ongoing creation of OHIN-OH International Network, founded as a spin-off result of SAPUVETNET. Finally, some examples of cooperation development projects characterised by an OH approach are also briefly mentioned.
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Rapidity-odd directed flow (v1) measurements for charged pions, protons, and antiprotons near midrapidity (y=0) are reported in sNN=7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV Au+Au collisions as recorded by the STAR detector at the Relativistic Heavy Ion Collider. At intermediate impact parameters, the proton and net-proton slope parameter dv1/dy|y=0 shows a minimum between 11.5 and 19.6 GeV. In addition, the net-proton dv1/dy|y=0 changes sign twice between 7.7 and 39 GeV. The proton and net-proton results qualitatively resemble predictions of a hydrodynamic model with a first-order phase transition from hadronic matter to deconfined matter, and differ from hadronic transport calculations.
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The aim of this study was to evaluate the effectiveness of 17% ethylene-diamine-tetra-acetic acid (EDTA) used alone or associated with 2% chlorhexidine gel (CHX) on intracanal medications (ICM) removal. Sixty single-rooted human teeth with fully formed apex were selected. The cervical and middle thirds of each canal were prepared with Gates Glidden drills and rotary files. The apical third was shaped with hand files. The specimens were randomly divided into two groups depending on the ICM used after instrumentation: calcium hydroxide Ca(OH)(2) +CHX or Ca(OH)(2) +sterile saline (SS). After seven days, each group was divided into subgroups according to the protocol used for ICM removal: instrumentation and irrigation either with EDTA, CHX+EDTA, or SS (control groups). All specimens were sectioned and processed for observation of the apical thirds by using scanning electron microscopy. Two calibrated evaluators attributed scores to each specimen. The differences between the protocols for ICM removal were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Friedman and Wilcoxon signed rank tests were used for comparison between the score of debris obtained in each root canal third. Remains of Ca(OH)(2) were found in all specimens independently of the protocol and ICM used (P > 0.05). Seventeen percent EDTA showed the best results in removing ICM when used alone (P < 0.05), particularly in those associated with CHX. It was concluded that the chelating agent 17% EDTA significantly improved the removal of ICM when used alone. Furthermore, the type of the vehicle associated with Ca(OH)(2) also plays a role in the ICM removal.