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1.
Nature ; 581(7809): 396-400, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32461650

RESUMEN

Molecular spectroscopy offers opportunities for the exploration of the fundamental laws of nature and the search for new particle physics beyond the standard model1-4. Radioactive molecules-in which one or more of the atoms possesses a radioactive nucleus-can contain heavy and deformed nuclei, offering high sensitivity for investigating parity- and time-reversal-violation effects5,6. Radium monofluoride, RaF, is of particular interest because it is predicted to have an electronic structure appropriate for laser cooling6, thus paving the way for its use in high-precision spectroscopic studies. Furthermore, the effects of symmetry-violating nuclear moments are strongly enhanced5,7-9 in molecules containing octupole-deformed radium isotopes10,11. However, the study of RaF has been impeded by the lack of stable isotopes of radium. Here we present an experimental approach to studying short-lived radioactive molecules, which allows us to measure molecules with lifetimes of just tens of milliseconds. Energetically low-lying electronic states were measured for different isotopically pure RaF molecules using collinear resonance ionisation at the ISOLDE ion-beam facility at CERN. Our results provide evidence of the existence of a suitable laser-cooling scheme for these molecules and represent a key step towards high-precision studies in these systems. Our findings will enable further studies of short-lived radioactive molecules for fundamental physics research.

2.
Neuropsychol Rev ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38862725

RESUMEN

To effectively diagnose and treat subjective cognitive symptoms in post-acute sequalae of COVID-19 (PASC), it is important to understand objective cognitive impairment across the range of acute COVID-19 severity. Despite the importance of this area of research, to our knowledge, there are no current meta-analyses of objective cognitive functioning following non-severe initial SARS-CoV-2 infection. The aim of this meta-analysis is to describe objective cognitive impairment in individuals with non-severe (mild or moderate) SARS-CoV-2 cases in the post-acute stage of infection. This meta-analysis was pre-registered with Prospero (CRD42021293124) and utilized the PRISMA checklist for reporting guidelines, with screening conducted by at least two independent reviewers for all aspects of the screening and data extraction process. Fifty-nine articles (total participants = 22,060) with three types of study designs met our full criteria. Individuals with non-severe (mild/moderate) initial SARS-CoV-2 infection demonstrated worse objective cognitive performance compared to healthy comparison participants. However, those with mild (nonhospitalized) initial SARS-CoV-2 infections had better objective cognitive performance than those with moderate (hospitalized but not requiring ICU care) or severe (hospitalized with ICU care) initial SARS-CoV-2 infections. For studies that used normative data comparisons instead of healthy comparison participants, there was a small and nearly significant effect when compared to normative data. There were high levels of heterogeneity (88.6 to 97.3%), likely reflecting small sample sizes and variations in primary study methodology. Individuals who have recovered from non-severe cases of SARS-CoV-2 infections may be at risk for cognitive decline or impairment and may benefit from cognitive health interventions.

3.
J Head Trauma Rehabil ; 39(4): 258-272, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38270528

RESUMEN

MAIN OBJECTIVE: Cognitive difficulties are some of the most frequently experienced symptoms following mild-to-moderate traumatic brain injuries (TBIs). There is meta-analytic evidence that cognitive rehabilitation improves cognitive functioning after TBI in nonveteran populations but not specifically within the veteran and service member (V/SM) population. The purpose of the current meta-analysis was to examine the effect of cognitive rehabilitation interventions for V/SMs with a history of mild-to-moderate TBI. DESIGN AND MAIN MEASURES: This meta-analysis was preregistered with PROSPERO (CRD42021262902) and used the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) checklist for reporting guidelines. Inclusion criteria required studies to have (1) randomized controlled trials; (2) used adult participants (aged 18 years or older) who were US veterans or active-duty service members who had a history of mild-to-moderate TBI; (3) cognitive rehabilitation treatments designed to improve cognition and/or everyday functioning; (4) used objective neuropsychological testing as a primary outcome measure; and (5) been published in English. At least 2 reviewers independently screened all identified abstracts and full-text articles and coded demographic and effect size data. The final search was run on February 24, 2023, using 4 databases (PubMed, PsycINFO, Web of Science, and Google Scholar). Study quality and bias were examined using the revised Cochrane Risk-of-Bias Tool for Randomized Trials. RESULTS: We identified 8 articles meeting full criteria (total participants = 564; 97% of whom had a history of mild TBI). Compared with control groups, participants showed a small, but significant, improvement in overall objective neuropsychological functioning after cognitive rehabilitation interventions. Interventions focusing on teaching strategies had a larger effect size than did those focusing on drill-and-practice approaches for both objective neuropsychological test performance and performance-based measures of functional capacity. CONCLUSION: There is evidence of cognitive improvement in V/SMs with TBI histories after participation in cognitive rehabilitation. Clinician-administered interventions focusing on teaching strategies may yield the greatest cognitive improvement in this population.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Personal Militar , Veteranos , Humanos , Lesiones Traumáticas del Encéfalo/rehabilitación , Terapia Cognitivo-Conductual/métodos , Masculino , Femenino , Adulto , Entrenamiento Cognitivo
4.
Hum Brain Mapp ; 44(5): 1888-1900, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36583562

RESUMEN

Traumatic brain injury (TBI) in military populations can cause disruptions in brain structure and function, along with cognitive and psychological dysfunction. Diffusion magnetic resonance imaging (dMRI) can detect alterations in white matter (WM) microstructure, but few studies have examined brain asymmetry. Examining asymmetry in large samples may increase sensitivity to detect heterogeneous areas of WM alteration in mild TBI. Through the Enhancing Neuroimaging Genetics Through Meta-Analysis Military-Relevant Brain Injury working group, we conducted a mega-analysis of neuroimaging and clinical data from 16 cohorts of Active Duty Service Members and Veterans (n = 2598). dMRI data were processed together along with harmonized demographic, injury, psychiatric, and cognitive measures. Fractional anisotropy in the cingulum showed greater asymmetry in individuals with deployment-related TBI, driven by greater left lateralization in TBI. Results remained significant after accounting for potentially confounding variables including posttraumatic stress disorder, depression, and handedness, and were driven primarily by individuals whose worst TBI occurred before age 40. Alterations in the cingulum were also associated with slower processing speed and poorer set shifting. The results indicate an enhancement of the natural left laterality of the cingulum, possibly due to vulnerability of the nondominant hemisphere or compensatory mechanisms in the dominant hemisphere. The cingulum is one of the last WM tracts to mature, reaching peak FA around 42 years old. This effect was primarily detected in individuals whose worst injury occurred before age 40, suggesting that the protracted development of the cingulum may lead to increased vulnerability to insults, such as TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Lesiones Encefálicas , Sustancia Blanca , Humanos , Adulto , Sustancia Blanca/patología , Pruebas Neuropsicológicas , Lesiones Encefálicas/patología , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/patología , Encéfalo
5.
Neuropsychol Rev ; 33(1): 42-121, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-33721207

RESUMEN

There is evidence that diffusion-weighted imaging (DWI) is able to detect tissue alterations following mild traumatic brain injury (mTBI) that may not be observed on conventional neuroimaging; however, findings are often inconsistent between studies. This systematic review assesses patterns of differences in DWI metrics between those with and without a history of mTBI. A PubMed literature search was performed using relevant indexing terms for articles published prior to May 14, 2020. Findings were limited to human studies using DWI in mTBI. Articles were excluded if they were not full-length, did not contain original data, if they were case studies, pertained to military populations, had inadequate injury severity classification, or did not report post-injury interval. Findings were reported independently for four subgroups: acute/subacute pediatric mTBI, acute/subacute adult mTBI, chronic adult mTBI, and sport-related concussion, and all DWI acquisition and analysis methods used were included. Patterns of findings between studies were reported, along with strengths and weaknesses of the current state of the literature. Although heterogeneity of sample characteristics and study methods limited the consistency of findings, alterations in DWI metrics were most commonly reported in the corpus callosum, corona radiata, internal capsule, and long association pathways. Many acute/subacute pediatric studies reported higher FA and lower ADC or MD in various regions. In contrast, acute/subacute adult studies most commonly indicate lower FA within the context of higher MD and RD. In the chronic phase of recovery, FA may remain low, possibly indicating overall demyelination or Wallerian degeneration over time. Longitudinal studies, though limited, generally indicate at least a partial normalization of DWI metrics over time, which is often associated with functional improvement. We conclude that DWI is able to detect structural mTBI-related abnormalities that may persist over time, although future DWI research will benefit from larger samples, improved data analysis methods, standardized reporting, and increasing transparency.


Asunto(s)
Conmoción Encefálica , Sustancia Blanca , Adulto , Humanos , Niño , Conmoción Encefálica/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Neuroimagen , Estudios Longitudinales , Encéfalo/diagnóstico por imagen
6.
Prev Sci ; 24(6): 1174-1186, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36933101

RESUMEN

We present results of a randomized, controlled, efficacy trial of a handbook intervention for parents of first-year college students. The aim of the interactive intervention was to decrease risk behaviors by increasing family protective factors. The handbook, based in self-determination theory and the social development model, provided evidence-based and developmentally targeted suggestions for parents to engage with their students in activities designed to support successful adjustment to college. We recruited 919 parent-student dyads from incoming students enrolled at a university in the U.S. Pacific Northwest and randomly assigned them to control and intervention conditions. We sent handbooks to intervention parents in June before students' August matriculation. Research assistants trained in motivational interviewing contacted parents to encourage use of the handbook. Control parents and students received treatment as usual. Participants completed baseline surveys during their final semester in high school (time 1) and their first semester at college (time 2). Self-reported frequency of alcohol, cannabis, and simultaneous use increased across both handbook and control students. In intent-to-treat analyses, odds of increased use were consistently lower and of similar magnitude for students in the intervention condition than in the control condition, and odds of first-time use were also lower in the intervention condition. Contact from research assistants predicted parents' engagement, and parent and student report of active engagement with handbook predicted lower substance use among intervention than control students across the transition to college. We developed a low-cost, theory-based handbook to help parents support their young adult children as they transition to independent college life. Students whose parents used the handbook were less likely to initiate or increase substance use than students in the control condition during their first semester in college.ClinicalTrials.gov Identifier: NCT03227809.


Asunto(s)
Estudiantes , Trastornos Relacionados con Sustancias , Adulto Joven , Humanos , Instituciones Académicas , Universidades , Padres , Trastornos Relacionados con Sustancias/prevención & control
7.
Behav Res Methods ; 55(6): 2813-2837, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35953660

RESUMEN

Researcher degrees of freedom can affect the results of hypothesis tests and consequently, the conclusions drawn from the data. Previous research has documented variability in accuracy, speed, and documentation of output across various statistical software packages. In the current investigation, we conducted Pearson's chi-square test of independence, Spearman's rank-ordered correlation, Kruskal-Wallis one-way analysis of variance, Wilcoxon Mann-Whitney U rank-sum tests, and Wilcoxon signed-rank tests, along with estimates of skewness and kurtosis, on large, medium, and small samples of real and simulated data in SPSS, SAS, Stata, and R and compared the results with those obtained through hand calculation using the raw computational formulas. Multiple inconsistencies were found in the results produced between statistical packages due to algorithmic variation, computational error, and statistical output. The most notable inconsistencies were due to algorithmic variations in the computation of Pearson's chi-square test conducted on 2 × 2 tables, where differences in p-values reported by different software packages ranged from .005 to .162, largely as a function of sample size. We discuss how such inconsistencies may influence the conclusions drawn from the results of statistical analyses depending on the statistical software used, and we urge researchers to analyze their data across multiple packages to check for inconsistencies and report details regarding the statistical procedure used for data analysis.


Asunto(s)
Proyectos de Investigación , Programas Informáticos , Humanos , Tamaño de la Muestra , Distribución de Chi-Cuadrado , Correlación de Datos
8.
Hum Brain Mapp ; 43(14): 4492-4507, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35678552

RESUMEN

Individual neuroanatomy can influence motor responses to transcranial magnetic stimulation (TMS) and corticomotor excitability after intermittent theta burst stimulation (iTBS). The purpose of this study was to examine the relationship between individual neuroanatomy and both TMS response measured using resting motor threshold (RMT) and iTBS measured using motor evoked potentials (MEPs) targeting the biceps brachii and first dorsal interosseus (FDI). Ten nonimpaired individuals completed sham-controlled iTBS sessions and underwent MRI, from which anatomically accurate head models were generated. Neuroanatomical parameters established through fiber tractography were fiber tract surface area (FTSA), tract fiber count (TFC), and brain scalp distance (BSD) at the point of stimulation. Cortical magnetic field induced electric field strength (EFS) was obtained using finite element simulations. A linear mixed effects model was used to assess effects of these parameters on RMT and iTBS (post-iTBS MEPs). FDI RMT was dependent on interactions between EFS and both FTSA and TFC. Biceps RMT was dependent on interactions between EFS and and both FTSA and BSD. There was no groupwide effect of iTBS on the FDI but individual changes in corticomotor excitability scaled with RMT, EFS, BSD, and FTSA. iTBS targeting the biceps was facilitatory, and dependent on FTSA and TFC. MRI-based measures of neuroanatomy highlight how individual anatomy affects motor system responses to different TMS paradigms and may be useful for selecting appropriate motor targets when designing TMS based therapies.


Asunto(s)
Corteza Motora , Estimulación Magnética Transcraneal , Potenciales Evocados Motores/fisiología , Humanos , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiología , Neuroanatomía , Plasticidad Neuronal/fisiología , Ritmo Teta/fisiología
9.
Toxicol Appl Pharmacol ; 434: 115821, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34896435

RESUMEN

We examined whether combinations of Kv7 channel openers could be effective modifiers of deep tissue nociceptor activity; and whether such combinations could then be optimized for use as safe analgesics for pain-like signs that developed in a rat model of GWI (Gulf War Illness) pain. Voltage clamp experiments were performed on subclassified nociceptors isolated from rat DRG (dorsal root ganglion). A stepped voltage protocol was applied (-55 to -40 mV; Vh = -60 mV; 1500 ms) and Kv7 evoked currents were subsequently isolated by linopirdine subtraction. Directly activated and voltage activated K+ currents were characterized in the presence and absence of Retigabine (5-100 µM) and/or Diclofenac (50-140 µM). Retigabine produced substantial voltage dependent effects and a maximal sustained current of 1.14 pA/pF ± 0.15 (ED50: 62.7 ± 3.18 µM). Diclofenac produced weak voltage dependent effects but a similar maximum sustained current of 1.01 ± 0.26 pA/pF (ED50: 93.2 ± 8.99 µM). Combinations of Retigabine and Diclofenac substantially amplified resting currents but had little effect on voltage dependence. Using a cholinergic challenge test (Oxotremorine, 10 µM) associated with our GWI rat model, combinations of Retigabine (5 uM) and Diclofenac (2.5, 20 and 50 µM) substantially reduced or totally abrogated action potential discharge to the cholinergic challenge. When combinations of Retigabine and Diclofenac were used to relieve pain-signs in our rat model of GWI, only those combinations associated with serious subacute side effects could relieve pain-like behaviors.


Asunto(s)
Carbamatos/farmacología , Dolor Crónico/tratamiento farmacológico , Canales de Potasio KCNQ/metabolismo , Síndrome del Golfo Pérsico/tratamiento farmacológico , Fenilendiaminas/farmacología , Potenciales de Acción/efectos de los fármacos , Analgésicos , Animales , Antiinflamatorios no Esteroideos/farmacología , Diclofenaco/farmacología , Ganglios Espinales/citología , Ganglios Espinales/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Canales de Potasio KCNQ/genética , Masculino , Neuronas/efectos de los fármacos , Oxotremorina/farmacología , Ratas , Ratas Sprague-Dawley
10.
Echocardiography ; 39(2): 240-247, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35034372

RESUMEN

INTRODUCTION: Cardiac point-of-care ultrasound (c-POCUS) is an increasingly implemented diagnostic tool with the potential to guide clinical management. We sought to characterize and analyze the existing c-POCUS literature with a focus on the temporal trends and differences across specialties. METHODS: A literature search for c-POCUS and related terms was conducted using Ovid (MEDLINE and Embase) and Web of Science databases through 2020. Eligible publications were classified by publication type and topic, author specialty, geographical region of senior author, and journal specialty. RESULTS: The initial search produced 1761 potential publications. A strict definition of c-POCUS yielded a final total of 574 cardiac POCUS manuscripts. A yearly increase in c-POCUS publications was observed. Nearly half of publications were original research (48.8%) followed by case report or series (22.8%). Most publications had an emergency medicine senior author (38.5%), followed by cardiology (20.8%), anesthesiology (12.5%), and critical care (12.5%). The proportion authored by emergency medicine and cardiologists has decreased over time while those by anesthesiology and critical care has generally increased, particularly over the last decade. First authorship demonstrated a similar trend. Articles were published in emergency medicine (24.4%) and cardiology journals (20.5%) with comparable frequency. CONCLUSION: The annual number of c-POCUS publications has steadily increased over time, reflecting the increased recognition and utilization of c-POCUS. This study can help inform clinicians of the current state of c-POCUS and augment the discussion surrounding barriers to continued adoption across all specialties.


Asunto(s)
Sistemas de Atención de Punto , Pruebas en el Punto de Atención , Cuidados Críticos , Corazón , Humanos , Ultrasonografía
11.
Hippocampus ; 31(4): 408-421, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33432734

RESUMEN

Episodic memory depends on the computational process of pattern separation in order to establish distinct memory representations of similar episodes. Studies of pattern separation in humans rely on mnemonic discrimination tasks, which have been shown to tax hippocampal-dependent pattern separation. Although previous neuroimaging research has focused on hippocampal processing, little is known about how other brain regions, known to be involved in recognition memory performance, are involved in mnemonic discrimination tasks. Conversely, neuroimaging studies of pattern separation with whole-brain coverage lack spatial resolution to localize activation to hippocampal subfields. In this study, 48 healthy young adult participants underwent whole-brain high-resolution functional MRI (fMRI) scanning while completing a mnemonic discrimination task. A priori region-of-interest analyses revealed activation patterns consistent with pattern separation in distinct hippocampal subregions, particularly in the subiculum. Connectivity analyses revealed a network of cortical regions consistent with the memory retrieval network where fMRI activation was correlated with hippocampal activation. An exploratory whole-brain analysis revealed widespread activation differentially associated with performance of the mnemonic discrimination task. Taken together, these results suggest that a network of brain regions contribute to mnemonic discrimination performance, with the hippocampus and parahippocampal cortex as a hub in the network displaying clear signals consistent with pattern separation and regions such as the dorsal medial prefrontal cortex particularly important for successful lure discrimination.


Asunto(s)
Hipocampo , Memoria Episódica , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Hipocampo/diagnóstico por imagen , Hipocampo/fisiología , Humanos , Imagen por Resonancia Magnética , Reconocimiento en Psicología/fisiología , Adulto Joven
12.
Phys Rev Lett ; 127(3): 033001, 2021 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-34328758

RESUMEN

Isotope shifts of ^{223-226,228}Ra^{19}F were measured for different vibrational levels in the electronic transition A^{2}Π_{1/2}←X^{2}Σ^{+}. The observed isotope shifts demonstrate the particularly high sensitivity of radium monofluoride to nuclear size effects, offering a stringent test of models describing the electronic density within the radium nucleus. Ab initio quantum chemical calculations are in excellent agreement with experimental observations. These results highlight some of the unique opportunities that short-lived molecules could offer in nuclear structure and in fundamental symmetry studies.

13.
Behav Pharmacol ; 32(4): 278-285, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33491991

RESUMEN

Intravenous drug self-administration remains the 'gold standard' for assessing abuse liability. Failure of a drug to maintain self-administration might indicate the absence of positive reinforcing effects but might also indicate the presence of aversive effects. Sensitivity to aversive and punishing effects of drugs (as well as nondrug stimuli) might collectively determine the likelihood of use, abuse and relapse. Using a choice procedure, this study compared the effects of remifentanil (mu opioid receptor agonist; 0.001-0.01 mg/kg/infusion) and histamine (H1-4 receptor agonist; 0.32-3.2 mg/kg/infusion), alone and in mixtures, to test the hypothesis that remifentanil/histamine mixtures are less reinforcing compared with remifentanil alone and less punishing compared with histamine alone. Male Sprague-Dawley rats (n = 10) chose between an intravenous infusion + a pellet and a pellet alone. Rats were indifferent to saline, chose remifentanil + a pellet over a pellet alone, and chose a pellet alone over histamine + a pellet. The effects of remifentanil/histamine mixtures generally were different from the constituent doses of histamine alone but not from remifentanil alone. A mixture containing 3.2 mg/kg/infusion histamine and either 0.001 or 0.0032 mg/kg/infusion remifentanil was not different from saline but was different from the effects of the constituent dose, insofar as choice increased compared with 3.2 mg/kg/infusion histamine alone and decreased compared with 0.001 or 0.0032 mg/kg/infusion remifentanil alone. Reinforcing doses of remifentanil combined with punishing doses of histamine can yield mixtures that are neither preferred nor avoided, offering 'proof-of-principle' for using drug mixtures to avoid adverse effects of opioid receptor agonists.


Asunto(s)
Conducta de Elección/efectos de los fármacos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Histamina/farmacología , Refuerzo en Psicología , Remifentanilo , Autoadministración/psicología , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/farmacología , Animales , Conducta Animal/efectos de los fármacos , Formas de Dosificación , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Composición de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Agonistas de los Receptores Histamínicos/farmacología , Infusiones Intravenosas/métodos , Ratas , Receptores Opioides mu/agonistas , Remifentanilo/efectos adversos , Remifentanilo/farmacología
14.
Rev Sci Tech ; 39(1): 283-288, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32729559

RESUMEN

Veterinary certificates have been an integral component of animal and animal product trade for many years. These certificates are agreed to by trading partners during bilateral or multilateral negotiations on the trade of animals and animal products, and provide assurance that goods are free from specific diseases. Many countries seek to implement or adopt a more streamlined and secure method of information exchange, with some implementing the electronic exchange of certificates for cross-border trade. Such an exchange of data has many advantages over its paper counterpart, including a streamlined business process, better accessibility to information (particularly in advance of shipment arrival) and the reduction of fraudulent certificates. Although there are some challenges related to this initiative and important considerations to be taken into account for its implementation, many countries are becoming aware of its efficiencies, leading to more productive and mutually beneficial trading-partner relationships.


Les certificats vétérinaires sont une composante essentielle des échanges internationaux d'animaux et de produits d'origine animale depuis de nombreuses années. Il s'agit de certificats approuvés préalablement par les partenaires commerciaux lors de négociations bilatérales ou multilatérales relatives aux échanges d'animaux et de produits d'origine animale et qui apportent la garantie que les marchandises échangées sont indemnes de certaines maladies spécifiées. Plusieurs pays ont cherché à mettre en oeuvre ou à valider une procédure d'échange d'informations à la fois plus simple et plus sûre ; parmi eux certains ont mis en place un système de certification électronique pour les échanges transfrontaliers. Ce type de transmission de données présente de nombreux avantages par rapport à la délivrance de certificats papier : un processus opérationnel rationalisé, un meilleur accès à l'information (en particulier avant l'arrivée d'une cargaison) et un nombre réduit de certificats frauduleux. Bien que certains problèmes en lien avec cette initiative restent encore à résoudre et que plusieurs aspects importants devront être pris en compte lors de sa mise en oeuvre, un nombre croissant de pays prennent conscience du fait que les performances d'un tel système contribueront à des relations plus productives et mutuellement bénéfiques entre partenaires commerciaux.


Hace ya muchos años que los certificados veterinarios son un componente intrínseco del comercio de animales y productos de origen animal. Estos certificados, acordados por las partes en el curso de negociaciones bilaterales o multilaterales sobre ese tipo de comercio, aportan la garantía de que las mercancías están exentas de una u otra enfermedad. Muchos países están tratando de aplicar o adoptar un método más ágil y seguro para intercambiar información, y algunos están implantando el intercambio de certificados por vía electrónica para operaciones comerciales transfronterizas. Esta modalidad de transmisión de datos presenta muchas ventajas con respecto al uso del papel, en particular porque agiliza los procesos de trabajo, facilita el acceso a la información (en particular, antes de que llegue la mercancía) y reduce los casos de certificados fraudulentos. Aunque esta iniciativa no deja de presentar dificultades y hay importantes consideraciones que es preciso tener en cuenta para llevarla adelante, muchos países van cobrando conciencia de que trae consigo procesos más eficientes y se traduce en relaciones más productivas y mutuamente beneficiosas entre los socios comerciales.


Asunto(s)
Comercio , Cooperación Internacional , Animales
15.
Phys Rev Lett ; 122(23): 233001, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31298870

RESUMEN

We introduce and present a theory of interferometric measurement of a normal Auger decay lifetime in molecules. Molecular Auger interferometry is based on the coherent phase control of Auger dynamics in a two-color (ω/2ω) laser field. We show that, in contrast to atoms, in oriented molecules of certain point groups the relative ω/2ω phase modulates the total ionization yield. A simple analytical formula is derived for the extraction of the lifetimes of Auger-active states from a molecular Auger interferogram, circumventing the need in either high-resolution or attosecond spectroscopy. We demonstrate the principle of the interferometric Auger lifetime measurement using inner-valence decay in CH_{3}F.

16.
Acta Paediatr ; 108(8): 1398-1405, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30825228

RESUMEN

AIM: Structured light plethysmography (SLP) is a novel light-based method that captures chest wall movements to evaluate tidal breathing. We carried out a narrative mini review of the clinical use of SLP in paediatrics. METHODS: PubMed and Google Scholar were searched for papers published in English up to December 2018. This identified a methodology paper published in 2010 and eight full papers, including three paediatric studies and one paediatric case report. We also included data from ten conference abstracts and one clinical case study. RESULTS: We found data that validated the ability of SLP to differentiate airway obstruction from tidal breathing parameters and bronchodilator responsiveness for children aged two years and over. Non-contact measurement of regional chest wall movement was a unique feature. Feasibility data were scarce and more studies are needed, especially in infants. Preliminary studies suggest that SLP has the potential to be used in cases of dysfunctional breathing and neuromuscular diseases and as a follow-up tool after lung infections or surgery. CONCLUSION: Structured light plethysmography has been validated to demonstrate lung function abnormality in paediatric asthma, but further studies are needed to demonstrate its benefits over current practice and how it can be used for other conditions.


Asunto(s)
Fotopletismografía , Respiración , Niño , Humanos
17.
Hippocampus ; 28(2): 108-120, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29149767

RESUMEN

Effective memory representations must be specific to prevent interference between episodes that may overlap in terms of place, time, or items present. Pattern separation, a computational process performed by the hippocampus, overcomes this interference by establishing nonoverlapping memory representations. Although it is widely accepted that declarative memories are consolidated during sleep, the effects of sleep on pattern separation have yet to be elucidated. We used whole-brain, high-resolution functional neuroimaging to investigate the effects of sleep on a task that places high demands on pattern separation. Sleep had a selective effect on memory specificity and not general recognition memory. Activity in brain regions related to memory retrieval and cognitive control demonstrated an interaction between sleep and delay. Surprisingly, there was no effect of sleep on hippocampal activity using a group-level analysis. To further understand the role of the hippocampus on our task, we performed a representational similarity analysis, which showed that hippocampal activation was biased toward pattern separation relative to cortical activation and that this bias increased following a delay (regardless of sleep). Cortical activation, conversely, was biased toward pattern completion and this bias was preferentially enhanced by sleep.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Memoria/fisiología , Sueño/fisiología , Adolescente , Adulto , Análisis de Varianza , Encéfalo/diagnóstico por imagen , Femenino , Hipocampo/diagnóstico por imagen , Hipocampo/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Estimulación Luminosa , Adulto Joven
18.
Proc Biol Sci ; 285(1880)2018 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-29899078

RESUMEN

Group living is widespread among animal species, and comes with a number of costs and benefits associated with foraging, predator avoidance and reproduction. It is largely unknown, however, whether individuals sacrifice exposure to their own preferred or optimal environmental conditions so they can remain part of a social group. Here, we demonstrate that individual three-spine sticklebacks vary in the degree to which they forego exposure to their preferred ambient temperature so they can associate with a group of conspecifics. Individual fish varied widely in preferred temperature when tested in isolation. When the same individuals were presented with a choice of a warm or cold thermal regime in the presence of a social group in one of the environments, fish spent more time with the group if it was close to their own individually preferred temperature. When a group was in a relatively cool environment, focal individuals that were more social deviated most strongly from their preferred temperature to associate with the group. Standard and maximum metabolic rate were not related to temperature preference or thermal compromise. However, individuals with a higher standard metabolic rate were less social, and so energetic demand may indirectly influence the environmental costs experienced by group members. The reduced tendency to engage with a social group when there is a large difference between the group temperature and the individual's preferred temperature suggests a role for temperature in group formation and cohesion that is mediated by individual physiology and behaviour. Together, these data highlight exposure to non-preferred temperatures as a potential cost of group membership that probably has important but to date unrecognized implications for metabolic demand, energy allocation, locomotor performance and overall group functioning.


Asunto(s)
Ambiente , Smegmamorpha/fisiología , Conducta Social , Animales , Temperatura
19.
Osteoarthritis Cartilage ; 26(3): 414-421, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29326062

RESUMEN

OBJECTIVE: Depletion of glycosaminoglycans (GAGs) and degradation of collagen network are early hallmarks of osteoarthritis (OA). Currently, there are no chondroprotective therapies that mitigate the loss of GAGs or effectively restore the collagen network. Recently, a novel polymeric cartilage supplement was described that forms a charged interpenetrating polymer network (IPN) reconstituting the hydrophilic properties of the extracellular matrix (ECM). To investigate the mechanism by which this hydrophilic IPN improves articular cartilage material properties, a finite element (FE) model is used to evaluate the IPN's effect on the fibrillar collagen network, nonfibrillar matrix, and interstitial fluid flow. METHODS: Bovine osteochondral plugs were degraded with chondroitinase ABC to selectively decrease GAG content. Samples were mechanically tested before and after IPN treatment using unconfined testing geometry and stress-relaxation protocol. Every measurement was modeled separately using a fibril-reinforced poroviscoelastic FE model. Measurement replication was achieved by optimizing the following model parameters: initial and strain-dependent fibril network modulus (Ef0, Efε, respectively), nonfibrillar matrix modulus (Enf), initial permeability (k0) and strain-dependent permeability factor (M). RESULTS: Based on the FE model results, treatment of native and GAG depleted cartilage with the hydrophilic IPN increases the ECM stiffness and impedes fluid flow. The IPN did not alter the stiffness of fibrillary network. Cartilage permeability and the strain-dependent permeability factor decreased with increasing IPN w/v%. CONCLUSIONS: The IPN reconstitutes cartilage material properties primarily by augmenting the hydrophilic ECM. This reinforcement of the solid phase also affects the fluid phase reestablishing low permeability.


Asunto(s)
Biopolímeros/farmacología , Cartílago Articular/efectos de los fármacos , Animales , Fenómenos Biomecánicos , Cartílago Articular/patología , Bovinos , Estrés Mecánico
20.
Toxicol Appl Pharmacol ; 352: 119-131, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29803855

RESUMEN

Many veterans of Operation Desert Storm (ODS) struggle with the chronic pain of Gulf War Illness (GWI). Exposure to insecticides and pyridostigmine bromide (PB) have been implicated in the etiology of this multisymptom disease. We examined the influence of 3 (DEET (N,N-diethyl-meta-toluamide), permethrin, chlorpyrifos) or 4 GW agents (DEET, permethrin, chlorpyrifos, pyridostigmine bromide (PB)) on the post-exposure ambulatory and resting behaviors of rats. In three independent studies, rats that were exposed to all 4 agents consistently developed both immediate and delayed ambulatory deficits that persisted at least 16 weeks after exposures had ceased. Rats exposed to a 3 agent protocol (PB excluded) did not develop any ambulatory deficits. Cellular and molecular studies on nociceptors harvested from 16WP (weeks post-exposure) rats indicated that vascular nociceptor Nav1.9 mediated currents were chronically potentiated following the 4 agent protocol but not following the 3 agent protocol. Muscarinic linkages to muscle nociceptor TRPA1 were also potentiated in the 4 agent but not the 3 agent, PB excluded, protocol. Although Kv7 activity changes diverged from the behavioral data, a Kv7 opener, retigabine, transiently reversed ambulation deficits. We concluded that PB played a critical role in the development of pain-like signs in a GWI rat model and that shifts in Nav1.9 and TRPA1 activity were critical to the expression of these pain behaviors.


Asunto(s)
Conducta Animal , Ganglios Espinales/metabolismo , Músculo Esquelético/inervación , Canal de Sodio Activado por Voltaje NAV1.9/metabolismo , Percepción del Dolor , Síndrome del Golfo Pérsico/metabolismo , Síndrome del Golfo Pérsico/psicología , Bromuro de Piridostigmina , Canal Catiónico TRPA1/metabolismo , Adaptación Fisiológica , Animales , Cloropirifos , DEET , Modelos Animales de Enfermedad , Ganglios Espinales/fisiopatología , Canales de Potasio KCNQ/metabolismo , Masculino , Umbral del Dolor , Permetrina , Síndrome del Golfo Pérsico/inducido químicamente , Síndrome del Golfo Pérsico/fisiopatología , Ratas Sprague-Dawley , Receptores Muscarínicos/metabolismo , Transducción de Señal , Factores de Tiempo
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