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Roaming is an unconventional type of molecular reaction where fragments, instead of immediately dissociating, remain weakly bound due to long-range Coulombic interactions. Due to its prevalence and ability to form new molecular compounds, roaming is fundamental to photochemical reactions in small molecules. However, the neutral character of the roaming fragment and its indeterminate trajectory make it difficult to identify experimentally. Here, we introduce an approach to image roaming, utilizing intense, femtosecond IR radiation combined with Coulomb explosion imaging to directly reconstruct the momentum vector of the neutral roaming H2, a precursor to H 3 + formation, in acetonitrile, CH3CN. This technique provides a kinematically complete picture of the underlying molecular dynamics and yields an unambiguous experimental signature of roaming. We corroborate these findings with quantum chemistry calculations, resolving this unique dissociative process.
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The capability to excite, probe, and manipulate vibrational modes is essential for understanding and controlling chemical reactions at the molecular level. Recent advancements in tip-enhanced Raman spectroscopies have enabled the probing of vibrational fingerprints in a single molecule with Ångström-scale spatial resolution. However, achieving controllable excitation of specific vibrational modes in individual molecules remains challenging. Here, we demonstrate the selective excitation and probing of vibrational modes in single deprotonated phthalocyanine molecules utilizing resonance Raman spectroscopy in a scanning tunneling microscope. Selective excitation is achieved by finely tuning the excitation wavelength of the laser to be resonant with the vibronic transitions between the molecular ground electronic state and the vibrational levels in the excited electronic state, resulting in the state-selective enhancement of the resonance Raman signal. Our approach contributes to setting the stage for steering chemical transformations in molecules on surfaces by selective excitation of molecular vibrations.
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We report an index patient with complete insensitivity to pain and a history of painless fractures, joint hypermobility, and behavioral problems. The index patient descends from a family with notable cases among his maternal relatives, including his aunt and his mother's first cousin, both of whom suffer from congenital insensitivity to pain. The patient had normal results for prior genetic testing: fragile-X syndrome testing, chromosomal microarray analysis, and exome sequencing. Optical genome mapping detected a homozygous deletion affecting the noncoding 5' untranslated region (UTR) and the first non-coding exon of the SCN9A gene in all affected family members, compatible with recessive disease transmission. Pathogenic homozygous loss-of-function variants in the SCN9A gene are associated with impaired pain sensation in humans. Optical genome mapping can thus detect pathogenic structural variants in patients without molecular etiology by standard diagnostic procedures and is a more accessible diagnostic tool than short-read or long-read whole-genome sequencing.
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Experimental glomerulonephritis results in hypertension that is sensitive to salt. Nevertheless, salt retention alone cannot explain the increase in blood pressure. Angiotensin antagonistic therapy reduces hypertension caused by puromycin amino nucleosides (PAN). We investigated the hypothesis that PAN modifies renal vascular reactivity through processes dependent on angiotensin. Long-Evans rats were given an intraperitoneal injection of either puromycin (150 mg/kg) or saline (controls). Group 1 was fed a normal sodium diet (NSD, n = 9). Group 2 was given 30 mg/L of quinapril (Q) in addition to NSD (NSD + Q; n = 6). Group 3 received a high sodium diet (HSD, n = 7), and Group 4 received HSD + Q (n = 7). Systolic blood pressure (SBP), plasma creatinine, proteinuria, and sodium balance were monitored for 12 days. On day 15, renal vascular reactivity was assessed by administering increasing doses of angiotensin II, acetylcholine (ACh), and sodium nitroprusside (SNP) directly into the renal artery. SBP progressively increased in all PAN groups. This increase in SBP was greater in the HSD groups and was not significantly altered by Q treatment. SBP increased by 22 ± 4% (NSD), 51 ± 5% (NSD + Q), 81 ± 10% (HSD), and 65 ± 8% (HSD + Q). The renal blood flow of PAN rats did not return to baseline despite their normal renal vasoconstrictor responses to angiotensin II. Additionally, they showed reduced renal vasodilator responses to SNP and Ach. The vasodilator responses to both vasodilators were surprisingly unaffected by the inhibition of the angiotensin-converting enzyme (ACE). Renal vasodilator responses to both endothelium-dependent and independent variables were reduced in early PAN-induced hypertension. We found that the angiotensin-mediated mechanism is not responsible for this altered renal vasoreactivity.
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Angiotensina II , Rim , Animais , Angiotensina II/farmacologia , Ratos , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Masculino , Ratos Long-Evans , Pressão Sanguínea/efeitos dos fármacos , Puromicina/farmacologia , Nitroprussiato/farmacologia , Puromicina Aminonucleosídeo , Acetilcolina/farmacologia , Nefropatias/induzido quimicamenteRESUMO
IL-27, a member of the IL-6/IL-12 cytokine superfamily, is primarily secreted by antigen presenting cells, specifically by dendric cells, macrophages and B cells. IL-27 has antiviral activities and modulates both innate and adaptive immune responses against viruses. The role of IL-27 in the setting of viral infections is not well defined and both pro-inflammatory and anti-inflammatory functions have been described. Here, we discuss the latest advancements in the role of IL-27 in several viral infection models of human disease. We highlight important aspects of IL-27 expression regulation, the critical cell sources at different stages of the infection and their impact in cell mediated immunity. Lastly, we discuss the need to better define the antiviral and modulatory (pro-inflammatory vs anti-inflammatory) properties of IL-27 in the context of human chronic viral infections.
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Imunidade Adaptativa , Viroses , Humanos , Viroses/imunologia , Animais , Regulação da Expressão Gênica , Interleucina-27/metabolismo , Vírus/imunologia , Interleucinas/imunologia , Interleucinas/metabolismoRESUMO
Introduction: HIV-1 infection may produce a detrimental effect on the immune response. Early start of antiretroviral therapy (ART) is recommended to preserve the integrity of the immune system. In fact, people with HIV (PWH) and normal CD4/CD8 ratio appear not to be more susceptible to severe forms of COVID-19 than the general population and they usually present a good seroconversion rate in response to vaccination against SARS-CoV-2. However, few studies have fully characterized the development of cytotoxic immune populations in response to COVID-19 vaccination in these individuals. Methods: In this study, we recruited PWH with median time of HIV-1 infection of 6 years, median CD4/CD8 ratio of 1.0, good adherence to ART, persistently undetectable viral load, and negative serology against SARS-CoV-2, who then received the complete vaccination schedule against COVID-19. Blood samples were taken before vaccination against COVID-19 and one month after receiving the complete vaccination schedule. Results: PWH produced high levels of IgG against SARS-CoV-2 in response to vaccination that were comparable to healthy donors, with a significantly higher neutralization capacity. Interestingly, the cytotoxic activity of PBMCs from PWH against SARS-CoV-2-infected cells was higher than healthy donors before receiving the vaccination schedule, pointing out the pre-existence of activated cell populations with likely unspecific antiviral activity. The characterization of these cytotoxic cell populations revealed high levels of Tgd cells with degranulation capacity against SARS-CoV-2-infected cells. In response to vaccination, the degranulation capacity of CD8+ T cells also increased in PWH but not in healthy donors. Discussion: The full vaccination schedule against COVID-19 did not modify the ability to respond against HIV-1-infected cells in PWH and these individuals did not show more susceptibility to breakthrough infection with SARS-CoV-2 than healthy donors after 12 months of follow-up. These results revealed the development of protective cell populations with broad-spectrum antiviral activity in PWH with normal CD4/CD8 ratio and confirmed the importance of early ART and treatment adherence to avoid immune dysfunctions.
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Relação CD4-CD8 , COVID-19 , Infecções por HIV , SARS-CoV-2 , Humanos , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Infecções por HIV/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Vacinas contra COVID-19/imunologia , Linfócitos T CD8-Positivos/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , HIV-1/imunologia , Citotoxicidade Imunológica , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Linfócitos T Citotóxicos/imunologia , VacinaçãoRESUMO
BACKGROUNDWeakly virulent environmental mycobacteria (EM) can cause severe disease in HLA-DRB1*15:02 or 16:02 adults harboring neutralizing anti-IFN-γ autoantibodies (nAIGAs). The overall prevalence of nAIGAs in the general population is unknown, as are the penetrance of nAIGAs in HLA-DRB1*15:02 or 16:02 individuals and the proportion of patients with unexplained, adult-onset EM infections carrying nAIGAs.METHODSThis study analyzed the detection and neutralization of anti-IFN-γ autoantibodies (auto-Abs) from 8,430 healthy individuals of the general population, 257 HLA-DRB1*15:02 or 16:02 carriers, 1,063 patients with autoimmune disease, and 497 patients with unexplained severe disease due to EM.RESULTSWe found that anti-IFN-γ auto-Abs detected in 4,148 of 8,430 healthy individuals (49.2%) from the general population of an unknown HLA-DRB1 genotype were not neutralizing. Moreover, we did not find nAIGAs in 257 individuals carrying HLA-DRB1* 15:02 or 16:02. Additionally, nAIGAs were absent in 1,063 patients with an autoimmune disease. Finally, 7 of 497 patients (1.4%) with unexplained severe disease due to EM harbored nAIGAs.CONCLUSIONThese findings suggest that nAIGAs are isolated and that their penetrance in HLA-DRB1*15:02 or 16:02 individuals is low, implying that they may be triggered by rare germline or somatic variants. In contrast, the risk of mycobacterial disease in patients with nAIGAs is high, confirming that these nAIGAs are the cause of EM disease.FUNDINGThe Laboratory of Human Genetics of Infectious Diseases is supported by the Howard Hughes Medical Institute, the Rockefeller University, the St. Giles Foundation, the National Institutes of Health (NIH) (R01AI095983 and U19AIN1625568), the National Center for Advancing Translational Sciences (NCATS), the NIH Clinical and Translational Science Award (CTSA) program (UL1 TR001866), the French National Research Agency (ANR) under the "Investments for the Future" program (ANR-10-IAHU-01), the Integrative Biology of Emerging Infectious Diseases Laboratory of Excellence (ANR-10-LABX-62-IBEID), ANR-GENMSMD (ANR-16-CE17-0005-01), ANR-MAFMACRO (ANR-22-CE92-0008), ANRSECTZ170784, the French Foundation for Medical Research (FRM) (EQU201903007798), the ANRS-COV05, ANR GENVIR (ANR-20-CE93-003), and ANR AI2D (ANR-22-CE15-0046) projects, the ANR-RHU program (ANR-21-RHUS-08-COVIFERON), the European Union's Horizon 2020 research and innovation program under grant agreement no. 824110 (EASI-genomics), the Square Foundation, Grandir - Fonds de solidarité pour l'enfance, the Fondation du Souffle, the SCOR Corporate Foundation for Science, the Battersea & Bowery Advisory Group, William E. Ford, General Atlantic's Chairman and Chief Executive Officer, Gabriel Caillaux, General Atlantic's Co-President, Managing Director, and Head of business in EMEA, and the General Atlantic Foundation, Institut National de la Santé et de la Recherche Médicale (INSERM) and of Paris Cité University. JR was supported by the INSERM PhD program for doctors of pharmacy (poste d'accueil INSERM). JR and TLV were supported by the Bettencourt-Schueller Foundation and the MD-PhD program of the Imagine Institute. MO was supported by the David Rockefeller Graduate Program, the Funai Foundation for Information Technology (FFIT), the Honjo International Scholarship Foundation (HISF), and the New York Hideyo Noguchi Memorial Society (HNMS).
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Autoanticorpos , Doenças Autoimunes , Adulto , Humanos , Predisposição Genética para Doença , Genótipo , Cadeias HLA-DRB1/genética , Infecções por Mycobacterium não TuberculosasRESUMO
Kondo lattices are systems with unusual electronic properties that stem from strong electron correlation, typically studied in intermetallic 3D compounds containing lanthanides or actinides. Lowering the dimensionality of the system enhances the role of electron correlations providing a new tuning knob for the search of novel properties in strongly correlated quantum matter. The realization of a 2D Kondo lattice by stacking a single-layer Mott insulator on a metallic surface is reported. The temperature of the system is steadily lowered and by using high-resolution scanning tunneling spectroscopy, the phase transition leading to the Kondo lattice is followed. Above 27 K the interaction between the Mott insulator and the metal is negligible and both keep their original electronic properties intact. Below 27 K the Kondo screening of the localized electrons in the Mott insulator begins and below 11 K the formation of a coherent quantum electronic state extended to the entire sample, i.e., the Kondo lattice, takes place. By means of density functional theory, the electronic properties of the system and its evolution with temperature are explained. The findings contribute to the exploration of unconventional states in 2D correlated materials.
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We present a comprehensive theoretical study of valence-shell photoionization of the CO2 molecule by using the XCHEM methodology. This method makes use of a fully correlated molecular electronic continuum at a level comparable to that provided by state-of-the-art quantum chemistry packages in bound-state calculations. The calculated total and angularly resolved photoionization cross sections are presented and discussed, with particular emphasis on the series of autoionizing resonances that appear between the first and the fourth ionization thresholds. Ten series of Rydberg autoionizing states are identified, including some not previously reported in the literature, and their energy positions and widths are provided. This is relevant in the context of ongoing experimental and theoretical efforts aimed at observing in real-time (attosecond time scale) the autoionization dynamics in molecules.
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We developed an application model based on the System of Environmental Economic Accounting-Ecosystem Accounting (SEEA-EA) framework, endorsed by the United Nations Statistical Commission in 2021. This model enables mapping condition accounts for forest ecosystems using automated computation. We applied the model nationally in Spain between 2000 and 2015 to test its effectiveness. Our model follows five methodological steps to generate forest condition accounts: (i) definition and spatial delimitation of forest ecosystem types; (ii) selection of variables using the ecosystem condition typology encompassing physical, chemical, compositional, structural, functional, and landscape characteristics; (iii) establishment of reference levels, including lower (collapse) and upper (high ecosystem integrity) thresholds; (iv) aggregation of variables into condition index; and (v) calculation of a single condition index by rescaling the aggregated indicators between 0 and 1. The results obtained from the model provide valuable insights into the status and trends of individual condition indicators, as well as aggregated condition index values for forest ecosystems, in a spatially explicit manner. Overall, the condition of the forest ecosystems in Spain showed a slight increase, from 0.56 in 2000 to 0.58 in 2015. However, distinct trends were observed for each ecosystem type. For example, mixed Alpine and Macaronesia forests exhibited a significant improvement, while the continental Mediterranean coniferous forests did not show any change. This innovative approach to monitoring forest condition accounts has important potential applications in policy and decision-making processes. It can contribute to effective evidence-based nature conservation, ecosystem service management, and identifying restoration areas.
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Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Florestas , Espanha , PolíticasRESUMO
Resumen El concepto de bienestar subjetivo se refiere a la forma global, positiva o negativa, en la que las personas evalúan sus vidas y experiencias. La búsqueda de factores que expliquen el bienestar subjetivo, actualmente uno de los temas de mayor interés en la psicología, condujo al concepto de satisfacciones de dominios, que se entienden como los juicios que las personas hacen al evaluar los mayores dominios de vida. Este estudio correlacional tuvo por objetivo establecer la relación de la satisfacción en los dominios económico, de pareja, familia, amigos, salud, vida universitaria y rendimiento académico, con los componentes cognitivo y emocional del bienestar subjetivo (satisfacción vital y felicidad, respectivamente), identificando cuáles de esos dominios lo predicen. La muestra, no probabilística, estuvo conformada por 344 estudiantes de una universidad pública colombiana (50.9 % mujeres y 49.1 % hombres) con edades entre 18 y 29 años (. = 20.89; DT = 2.52). Los resultados mostraron una fuerte relación de todos los dominios con el bienestar subjetivo. La satisfacción en los dominios económico, de pareja, familia, amigos y vida universitaria explicó la varianza de la satisfacción vital y la felicidad en forma diferenciada. Se concluye que: (a) el bienestar se afecta con la satisfacción de necesidades asociadas a los dominios cercanos e importantes para el individuo; (b) las satisfacciones de dominios impactan más el componente cognitivo del bienestar que el emocional; (c) el dominio económico satisface más necesidades cognitivas, la amistad suple necesidades emocionales, y la pareja, la familia y la vida universitaria satisfacen ambas.
Abstract The concept of subjective well-being refers to the overall positive or negative way in which people evaluate their lives and experiences. It is generally accepted that subjective well-being is made up of a cognitive component usually called satisfaction with life or life satisfaction and an emotional component usually referred to as happiness. The search for factors that explain subjective well-being is currently one of the most interesting topics in psychology and led to the concept of domain satisfactions, which are understood as the judgments that people make when evaluating the major domains of life. It refers to the perceived degree of satisfaction that we obtain from the way in which each of these main domains or areas of our lives are developed. This correlational study with predictive intent aimed at establishing the relationship of satisfaction in the economic, couple, family, friends, health, university life, and academic performance domains, with the cognitive and emotional components of subjective well-being (life satisfaction and happiness, respectively), identifying which of these domains predict well-being. The non-probabilistic sample, for convenience, was made up of 344 women and men (50.9 % and 49.1 % respectively) between 18 and 29 years of age (M = 20.89); SD = 2.52), students from an important Colombian public university based in the city of Palmira. The instruments, which include the Diener's life satisfaction and Lyubomirsky and Lepper's happiness scales, and simple items for each domain satisfaction studied (economic, couple, family, friends, health, university life, and academic performance) were answered in a format printed by 64 % of the participants and in virtual format by 36 %, according to their own choice. The results showed that all domain satisfactions were significantly related to both the cognitive and the emotional components of subjective well-being. The results also showed that except for satisfaction with health and academic performance, all other domain satisfactions predicted at least one of the components of subjective well-being. In general, domain satisfactions explained the variance of satisfaction and happiness much better than sociodemographic variables. Thus, it was confirmed that the psychological significance of events that occur in the main areas of people´s lives have much more relevance to well-being than situational factors such as sociodemographic ones. In a different sense, and order of impact, satisfaction with the economic domain, satisfaction with university life, and satisfaction with the couple emerged as the domains that had the greatest influence on life satisfaction, and satisfaction with friends and satisfaction with university life emerged as the strongest predictors of happiness. The results suggest that well-being is especially affected by the satisfaction of needs associated with the closest domains and more important to the individual. These would include the economic domain and relationships that involve affections, but also other domains that, for specific reasons, occupy a relevant place in the individual's internal hierarchy of importance, which may vary among cultures and even among people of the same culture. The above conclusion could explain, among other findings, the significant impact of satisfaction with university life on subjective well-being. The results also suggest that, in general, domain satisfactions have a greater impact on the cognitive component of well-being than on the emotional component, and that, in particular, domains such as economics fundamentally satisfy cognitive needs, friendship fundamentally satisfy emotional needs, and other domains such as couple, family and university life, satisfy both cognitive and emotional needs. This would demonstrate the importance of applying differentiated instruments to study the cognitive and emotional components of well-being.
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The interplay between electronic and nuclear motions in molecules is a central concept in molecular science. To what extent it influences attosecond photoionization delays is an important, still unresolved question. Here, we apply attosecond electron-ion coincidence spectroscopy and advanced calculations that include both electronic and nuclear motions to study the photoionization dynamics of CH4 and CD4 molecules. These molecules are known to feature some of the fastest nuclear dynamics following photoionization. Remarkably, we find no measurable delay between the photoionization of CH4 and CD4, neither experimentally nor theoretically. However, we measure and calculate delays of up to 20 as between the dissociative and non-dissociative photoionization of the highest-occupied molecular orbitals of both molecules. Experiment and theory are in quantitative agreement. These results show that, in the absence of resonances, even the fastest nuclear motion does not substantially influence photoionization delays, but identify a previously unknown signature of nuclear motion in dissociative-ionization channels. These findings have important consequences for the design and interpretation of attosecond chronoscopy in molecules, clusters, and liquids.
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Introducción y objetivos: La infección por SARS-CoV-2 parece provocar en muchos atletas un deterioro funcional delrendimiento cardiopulmonar. Se estudió el impacto post COVID-19 en el sistema cardiopulmonar, a través del test de ergoespirometría máxima, en futbolistas profesionales elite. Material y método: La muestra estuvo compuesta por 10 futbolistas de la primera división AFA (Asociación de Fútbol Argentino), a quienes se realizaron test de consumo de oxígeno máximo (VO2máx) pre y post infección por COVID-19. Las variablesanalizadas fueron VO2máx absoluto y relativo, velocidad aeróbica máxima (VAM), primer umbral ventilatorio (VT1), segundoumbral ventilatorio (VT2), frecuencia cardiaca máxima (FCmáx) y cociente respiratorio (RER). Resultados: El promedio de la edad fue 22,4 ± 6,9 años, masa corporal 71,5 ± 7,1 kg y estatura 176,2 ± 6,9 cm. Los sujetospost COVID-19 disminuyeron significativamente un 18% el VO2VT2 (p =0,028) y el RER disminuyó significativamente 5%(p =0,02). La FCmax, fue la única variable que post COVID-19 se incrementó significativamente 1,8% (p =0,04). No se observaron cambios significativos en la masa corporal; 71,5 ± 7,1 vs 73,9 ± 7,4 (p <0,118), VO2máx 61,7 ± 5,2 vs 59,0 ± 5,1 ml·kg·min-1(p <0,213), VAM 18,7 ± 0,9 vs 18,6 ± 0,5 km·h-1 (p <0,739), VO2VT1 39,2 ± 4,0 vs 37,8 ± 4,3 ml·kg·min-1 (p <0,460), Velocidad alVT1 11,6 ± 0,5 vs 11,8 ± 0,6 (p <0,480) y demás variables. Conclusión: Parece razonable y seguro evaluar a los atletas después de la infección por SARS-CoV-2 con ergoespirometríapara asegurar las condiciones de salud y entrenabilidad. En este tipo de atletas (futbolistas elite), la utilización del segundoumbral ventilatorio (VT2) puede ser utilizado como estrategia para observar cambios pos COVID-19. La disminución hallada,puede estar relacionada más al cese del entrenamiento que al daño cardiopulmonar.(AU)
Introduction and objectives: The SARS-CoV-2 infection appears to cause functional impairment of cardiopulmonaryperformance in many athletes. We studied the post-COVID-19 impact on the cardiopulmonary system, through the maximalergospirometry test, in elite professional soccer players. Material and method: The sample consisted of 10 AFA (Argentine Football Association) first division soccer players, whounderwent pre and post COVID-19 infection maximal oxygen uptake (VO2max) tests. The variables analyzed were absolute andrelative VO2max, maximal aerobic speed (MAS), first ventilatory threshold (VT1), second ventilatory threshold (VT2), maximalheart rate (HRmax) and respiratory exercise ratio (RER). Results: The mean age was 22.4 ± 6.9 years, body mass 71.5 ± 7.1 kg and height 176.2 ± 6.9 cm. Post COVID-19 subjects significantly decreased VO2VT2 by 18% (P = 0.028) and RER significantly decreased by 5% (P = 0.02). HRmax was the only variablethat significantly increased post COVID-19 by 1.8% (P = 0.04). No significant changes was observed in body mass 71.5 ± 7.1 vs73.9 ± 7.4 (P< 0.118), VO2max 61.7 ± 5.2 vs 59.0 ± 5.1 ml·kg·min-1 (P<0,213), MAS 18.7 ± 0.9 vs 18.6 ± 0.5 km·h-1 (P<0,739), VO2VT139.2 ± 4.0 vs 37.8 ± 4.3 ml·kg·min-1 (P<0.460), speed al VT1 11.6 ± 0.5 vs 11.8 ± 0.6 (P <0.480) and other variables. Conclusion: It seems reasonable and safe to evaluate athletes after SARS-CoV-2 infection with ergospirometry to ensurehealth conditions and trainability. In this type of athletes (elite soccer players), the use of the second ventilatory threshold(VT2) can be used as a strategy to observe post-COVID-19 changes. The decrease found may be related more to the cessationof training than to cardiopulmonary damage.(AU)
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Humanos , Masculino , Adolescente , Adulto Jovem , Adulto , Infecções por Coronavirus/epidemiologia , Consumo de Oxigênio , Futebol , Atletas/estatística & dados numéricos , Desempenho Atlético/estatística & dados numéricos , Espirometria , Medicina Esportiva , Argentina , Frequência Cardíaca , Exercício FísicoRESUMO
The motion of atoms is at the heart of any chemical or structural transformation in molecules and materials. Upon activation of this motion by an external source, several (usually many) vibrational modes can be coherently coupled, thus facilitating the chemical or structural phase transformation. These coherent dynamics occur on the ultrafast timescale, as revealed, e.g., by nonlocal ultrafast vibrational spectroscopic measurements in bulk molecular ensembles and solids. Tracking and controlling vibrational coherences locally at the atomic and molecular scales is, however, much more challenging and in fact has remained elusive so far. Here, we demonstrate that the vibrational coherences induced by broadband laser pulses on a single graphene nanoribbon (GNR) can be probed by femtosecond coherent anti-Stokes Raman spectroscopy (CARS) when performed in a scanning tunnelling microscope (STM). In addition to determining dephasing (~440 fs) and population decay times (~1.8 ps) of the generated phonon wave packets, we are able to track and control the corresponding quantum coherences, which we show to evolve on time scales as short as ~70 fs. We demonstrate that a two-dimensional frequency correlation spectrum unequivocally reveals the quantum couplings between different phonon modes in the GNR.
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Covering 35% of Europe's land area, forest ecosystems play a crucial role in safeguarding biodiversity and mitigating climate change. Yet, forest degradation continues to undermine key ecosystem services that forests deliver to society. Here we provide a spatially explicit assessment of the condition of forest ecosystems in Europe following a United Nations global statistical standard on ecosystem accounting, adopted in March 2021. We measure forest condition on a scale from 0 to 1, where 0 represents a degraded ecosystem and 1 represents a reference condition based on primary or protected forests. We show that the condition across 44 forest types averaged 0.566 in 2000 and increased to 0.585 in 2018. Forest productivity and connectivity are comparable to levels observed in undisturbed or least disturbed forests. One third of the forest area was subject to declining condition, signalled by a reduction in soil organic carbon, tree cover density and species richness of threatened birds. Our findings suggest that forest ecosystems will need further restoration, improvements in management and an extended period of recovery to approach natural conditions.
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Carbono , Ecossistema , Solo , Florestas , Árvores , Biodiversidade , Europa (Continente)RESUMO
Oblique Fresnel peripheral prisms have been used for field expansion in homonymous hemianopia mobility such as walking and driving. However, limited field expansion, low image quality, and small eye scanning range limit their effectiveness. We developed a new oblique multi-periscopic prism using a cascade of rotated half-penta prisms, which provides 42° horizontal field expansion along with 18° vertical shift, high image quality, and wider eye scanning range. Feasibility and performance of a prototype using 3D-printed module are demonstrated by raytracing, photographic depiction, and Goldmann perimetry with patients with homonymous hemianopia.