715 research outputs found
Procedimiento de aplicación de sepiolitas básicas como catalizadores en reacciones de condensación de Knoevenagel
Referencia OEPM: P8904192.-- Fecha de solicitud: 12/12/1989.-- Titular: Consejo Superior de Investigaciones Científicas (CSIC).El procedimiento de invención se refiere a la aplicación de sepiolitas básicas como catalizadores en reacción de condensación de Knoevenagel. Las sepiolitas empleadas se obtienen mediante modificación de la sepiolita natural con iones alcalinos
o alcalinotérreos. Estos catalizadores poseen una elevada área superficial y un elevado volumen de poro.Peer reviewe
Fatigue properties of nanocrystallized surfaces obtained by high energy shot peening
AbstractAn unconventional method of shot peening aimed to generation of a nanograined layer over the surface of specimens has been applied by means of the standard air blast equipment but using peening parameters essentially different from typical ones. Surface nanocrystallization is verified and affirmed through different experimental procedures. Rotating bending fatigue tests are performed to evaluate the effect of this high energy shot peening and the nanocrystallized layer on fatigue life. First series results are available and the other tests are still in progress
GTM-3, an extra-large pore enantioselective chiral zeolitic catalyst
The development of chiral zeolitic catalysts possessing extra-large pores and endowed with the capability of enantioselectively processing bulky products represents one of the greatest challenges in chemistry. Here, we report the discovery of GTM-3, an enantio-enriched extra-large pore chiral zeolite material with -ITV framework structure, obtained using a simple enantiopure organic cation derived from the chiral pool, N,N-ethyl-methyl-pseudoephedrinium, as the chiral-inductor agent. We demonstrate the enantio-enrichment of GTM-3 in one of the two enantiomorphic polymorphs using the two enantiomers of the organic cation. Interestingly, we prove the ability of this zeolitic material to perform enantioselective catalytic operations with very large substrates, here exemplified by the catalytic epoxide aperture of the bulky trans-stilbene oxide with alcohols, yielding unprecedented product enantiomeric excesses up to 30%. Our discovery opens the way for the use of accessible chiral zeolitic materials for the catalytic asymmetric synthesis of chiral pharmaceutical compounds
The CHiME-7 UDASE task: Unsupervised domain adaptation for conversational speech enhancement
Supervised speech enhancement models are trained using artificially generated
mixtures of clean speech and noise signals, which may not match real-world
recording conditions at test time. This mismatch can lead to poor performance
if the test domain significantly differs from the synthetic training domain. In
this paper, we introduce the unsupervised domain adaptation for conversational
speech enhancement (UDASE) task of the 7th CHiME challenge. This task aims to
leverage real-world noisy speech recordings from the target test domain for
unsupervised domain adaptation of speech enhancement models. The target test
domain corresponds to the multi-speaker reverberant conversational speech
recordings of the CHiME-5 dataset, for which the ground-truth clean speech
reference is not available. Given a CHiME-5 recording, the task is to estimate
the clean, potentially multi-speaker, reverberant speech, removing the additive
background noise. We discuss the motivation for the CHiME-7 UDASE task and
describe the data, the task, and the baseline system
CNS Drugs
BACKGROUND: Hepatotoxicity may be a concern when prescribing antidepressants. Nevertheless, this risk remains poorly understood for serotonin and noradrenaline reuptake inhibitors (SNRIs: venlafaxine, milnacipran, duloxetine) and 'other antidepressants' (mianserin, mirtazapine, tianeptine and agomelatine), particularly in comparison with selective serotonin reuptake inhibitors (SSRIs: fluoxetine, citalopram, paroxetine, sertraline, fluvoxamine, escitalopram), which are by far the most commonly prescribed antidepressants. OBJECTIVE: We quantified the risk of serious liver injury associated with new use of SNRIs and 'other antidepressants' compared with SSRIs in real-life practice. METHODS: Based on the French national health insurance database, this cohort study included 4,966,825 individuals aged 25 years and older with a first reimbursement of SSRIs, SNRIs or 'other antidepressants' between January 2010 and June 2015. We compared the risk of serious liver injury within the 6 months following antidepressant initiation according to antidepressant class, with SSRIs as the reference, using an inverse probability-of-treatment-weighted Cox proportional hazard model adjusted for demographic characteristics and risk factors of liver injury. RESULTS: We identified 382 serious liver injuries overall (none for milnacipran initiators). Age and gender standardized incidence rates per 100,000 person-years were 19.2 for SSRIs, 22.2 for venlafaxine, 12.6 for duloxetine, 21.5 for mianserin, 32.8 for mirtazapine, 31.6 for tianeptine and 24.6 for agomelatine initiators. Initiation of antidepressants of interest versus SSRIs was not associated with an increased risk of serious liver injury [adjusted hazard ratios (95% confidence interval): venlafaxine 1.17 (0.83-1.64), duloxetine 0.54 (0.28-1.02), mianserin 0.90 (0.58-1.41), mirtazapine 1.17 (0.67-2.02), tianeptine 1.35 (0.82-2.23) and agomelatine 1.07 (0.51-2.23)]. This finding was confirmed by the results of an additional study using a case-time-control design. CONCLUSION: These results do not provide evidence of an increased risk of serious liver injury following initiation of SNRIs or 'other antidepressants' compared with SSRIs in real-life practice. This could reflect an inherent lack of difference in risk between the drug classes, or the fact that individuals with higher susceptibility to drug-induced liver injury are not prescribed drugs considered to be more hepatotoxic
Assessment of acute-phase protein response associated with the different pathological forms of bovine paratuberculosis
11 páginas, 1 tabla.In this study, the concentrations of two acute-phase proteins (APPs), haptoglobin (Hp)
and serum amyloid A (SAA), were quantitatively assessed in serum samples from cattle naturally
infected with paratuberculosis (PTB). APP profiles were compared across 190 animals classified
according to the different pathological forms associated with infection: uninfected (n = 59), with
focal lesions (n = 73), multifocal lesions (n = 19), and diffuse paucibacillary (n = 11) and diffuse
multibacillary lesions (n = 28). Our results showed a significant increase in both APPs in infected
animals compared to the control group, with differences depending on the type of lesion. Hp and SAA
levels were increased significantly in all infected animals, except in cows with diffuse multibacillary
lesions that showed similar values to non-infected animals. The expression pattern of both APPs
was similar and negatively correlated with the antibody levels against PTB. These results indicate
that the release of Hp and SAA is related to the presence of PTB lesions associated with a high
cell-mediated immune response and a lower bacterial load, suggesting that the pro-inflammatory
cytokines that are associated with these forms are the main stimulus for their synthesis. These
molecules could show some potential to be used as putative biomarkers of PTB infection, particularly
for the identification of subclinical animals showing pathological forms related to latency or resistance
to the development of advanced lesions.This study was funded by grants RTI2018-099496-B-I00 from the Spanish Ministry of Science and
Innovation and LE259/P18 from “Junta de Castilla y León”
Comparison of Pittsburgh compound B and florbetapir in cross-sectional and longitudinal studies.
IntroductionQuantitative in vivo measurement of brain amyloid burden is important for both research and clinical purposes. However, the existence of multiple imaging tracers presents challenges to the interpretation of such measurements. This study presents a direct comparison of Pittsburgh compound B-based and florbetapir-based amyloid imaging in the same participants from two independent cohorts using a crossover design.MethodsPittsburgh compound B and florbetapir amyloid PET imaging data from three different cohorts were analyzed using previously established pipelines to obtain global amyloid burden measurements. These measurements were converted to the Centiloid scale to allow fair comparison between the two tracers. The mean and inter-individual variability of the two tracers were compared using multivariate linear models both cross-sectionally and longitudinally.ResultsGlobal amyloid burden measured using the two tracers were strongly correlated in both cohorts. However, higher variability was observed when florbetapir was used as the imaging tracer. The variability may be partially caused by white matter signal as partial volume correction reduces the variability and improves the correlations between the two tracers. Amyloid burden measured using both tracers was found to be in association with clinical and psychometric measurements. Longitudinal comparison of the two tracers was also performed in similar but separate cohorts whose baseline amyloid load was considered elevated (i.e., amyloid positive). No significant difference was detected in the average annualized rate of change measurements made with these two tracers.DiscussionAlthough the amyloid burden measurements were quite similar using these two tracers as expected, difference was observable even after conversion into the Centiloid scale. Further investigation is warranted to identify optimal strategies to harmonize amyloid imaging data acquired using different tracers
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Being Surveyed Can Change Later Behavior and Related Parameter Estimates
Does completing a household survey change the later behavior of those surveyed? In three field studies of health and two of microlending, we randomly assigned subjects to be surveyed about health and/or household finances and then measured subsequent use of a related product with data that does not rely on subjects' self-reports. In the three health experiments, we find that being surveyed increases use of water treatment products and take-up of medical insurance. Frequent surveys on reported diarrhea also led to biased estimates of the impact of improved source water quality. In two microlending studies, we do not find an effect of being surveyed on borrowing behavior. The results suggest that limited attention could play an important but context-dependent role in consumer choice, with the implication that researchers should reconsider whether, how, and how much to survey their subjectsEconomic
Expressive Prosody in Patients With Focal Anterior Temporal Neurodegeneration
Background and objectivesProgressive focal anterior temporal lobe (ATL) neurodegeneration has been historically called semantic dementia. More recently, semantic variant primary progressive aphasia (svPPA) and semantic behavioral variant frontotemporal dementia (sbvFTD) have been linked with predominant left and right ATL neurodegeneration, respectively. Nonetheless, clinical tools for an accurate diagnosis of sbvFTD are still lacking. Expressive prosody refers to the modulation of pitch, loudness, tempo, and quality of voice used to convey emotional and linguistic information and has been linked to bilateral but right-predominant frontotemporal functioning. Changes in expressive prosody can be detected with semiautomated methods and could represent a useful diagnostic marker of socioemotional functioning in sbvFTD.MethodsParticipants underwent a comprehensive neuropsychological and language evaluation and a 3T MRI at the University of California San Francisco. Each participant provided a verbal description of the picnic scene from the Western Aphasia Battery. The fundamental frequency (f0) range, an acoustic measure of pitch variability, was extracted for each participant. We compared the f0 range between groups and investigated associations with an informant-rated measure of empathy, a facial emotion labeling task, and gray matter (GM) volumes using voxel-based morphometry.ResultsTwenty-eight patients with svPPA, 18 with sbvFTD, and 18 healthy controls (HCs) were included. f0 range was significantly different across groups: patients with sbvFTD showed reduced f0 range in comparison with both patients with svPPA (mean difference of -1.4 ± 2.4 semitones; 95% CI -2.4 to -0.4]; p < 0.005) and HCs (mean difference of -1.9 ± 3.0 semitones; 95% CI -3.0 to -0.7]; p < 0.001). A higher f0 range was correlated with a greater informant-rated empathy (r = 0.355; p ≤ 0.05), but not facial emotion labeling. Finally, the lower f0 range was correlated with lower GM volume in the right superior temporal gyrus, encompassing anterior and posterior portions (p < 0.05 FWE cluster corrected).DiscussionExpressive prosody may be a useful clinical marker of sbvFTD. Reduced empathy is a core symptom in sbvFTD; the present results extend this to prosody, a core component of social interaction, at the intersection of speech and emotion. They also inform the long-standing debate on the lateralization of expressive prosody in the brain, highlighting the critical role of the right superior temporal lobe
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