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1.
Nature ; 611(7935): 260-264, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36352135

RESUMO

In most cosmological models, rapid expansion of space marks the first moments of the Universe and leads to the amplification of quantum fluctuations1. The description of subsequent dynamics and related questions in cosmology requires an understanding of the quantum fields of the standard model and dark matter in curved spacetime. Even the reduced problem of a scalar quantum field in an explicitly time-dependent spacetime metric is a theoretical challenge2-5, and thus a quantum field simulator can lead to insights. Here we demonstrate such a quantum field simulator in a two-dimensional Bose-Einstein condensate with a configurable trap6,7 and adjustable interaction strength to implement this model system. We explicitly show the realization of spacetimes with positive and negative spatial curvature by wave-packet propagation and observe particle-pair production in controlled power-law expansion of space, using Sakharov oscillations to extract amplitude and phase information of the produced state. We find quantitative agreement with analytical predictions for different curvatures in time and space. This benchmarks and thereby establishes a quantum field simulator of a new class. In the future, straightforward upgrades offer the possibility to enter unexplored regimes that give further insight into relativistic quantum field dynamics.

2.
BMC Pregnancy Childbirth ; 24(1): 389, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796417

RESUMO

BACKGROUND: Negative childbirth experiences can be related to the onset of perinatal post-traumatic stress symptomatology (P-PTSS), which significantly impacts the mother and the infant. As a response in the face of the discomfort caused by P-PTSS, maladaptive emotion regulation strategies such as brooding can emerge, contributing to the consolidation of post-partum depressive symptoms. Ultimately, both types of symptomatology, P-PTSS and post-partum depression, can act as risk factors for developing mother-child bonding difficulties. Still, this full set of temporal paths has to date remained untested. The present longitudinal study aimed to analyze the risk factors associated with the appearance of P-PTSS after post-partum and to test a path model considering the role of P-PTSS as an indirect predictor of bonding difficulties at eight months of postpartum. METHODS: An initial sample of pregnant women in the third trimester of gestation (N = 594) participated in a longitudinal study comprising two follow-ups at two and eight months of postpartum. The mothers completed online evaluations that included socio-demographic data and measures of psychological variables. A two-step linear regression model was performed to assess the predictive role of the variables proposed as risk factors for P-PTSS, and a path model was formulated to test the pathways of influence of P-PTSS on bonding difficulties. RESULTS: A history of psychopathology of the mother, the presence of depression during pregnancy, the presence of medical complications in the mother, and the occurrence of traumatic birth experiences all acted as significant predictors of P-PTSS, explaining 29.5% of its variance. Furthermore, the path model tested further confirmed an indirect effect of P-PTSS, triggered by a negative childbirth experience, on subsequent bonding difficulties eight months after labor through its association with higher levels of brooding and, ultimately, postpartum depression levels. A further path showed that bonding difficulties at two months postpartum can persist at eight months postpartum due to the onset of brooding and postpartum depression symptoms. CONCLUSION: We identified a set of robust predictors of P-PTSS: the mother's previous history of depression, perinatal depression during pregnancy, the presence of medical complications in the mother and the occurrence of traumatic birth experiences, which has important implications for prevention. This is particularly relevant, as P-PTSS, when triggered by a negative childbirth experience, further indirectly predicted the development of mother-child bonding difficulties through the mediation of higher use of brooding and symptoms of postpartum depression. These findings can serve as a basis for developing new longitudinal studies to further advance the understanding of perinatal mechanisms of mental health.


Assuntos
Depressão Pós-Parto , Relações Mãe-Filho , Apego ao Objeto , Transtornos de Estresse Pós-Traumáticos , Humanos , Feminino , Transtornos de Estresse Pós-Traumáticos/psicologia , Estudos Longitudinais , Adulto , Relações Mãe-Filho/psicologia , Gravidez , Depressão Pós-Parto/psicologia , Fatores de Risco , Período Pós-Parto/psicologia , Parto/psicologia , Mães/psicologia , Lactente , Adulto Jovem
3.
Chaos ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38572944

RESUMO

We have studied the rich dynamics of a damped particle inside an external double-well potential under the influence of state-dependent time-delayed feedback. In certain regions of the parameter space, we observe multistability with the existence of two different attractors (limit cycle or strange attractor) with well separated mean Lyapunov energies forming a two-level system. Bifurcation analysis reveals that, as the effects of the time-delay feedback are enhanced, chaotic transitions emerge between the two wells of the double-well potential for the attractor corresponding to the fundamental energy level. By computing the residence time distributions and the scaling laws near the onset of chaotic transitions, we rationalize this apparent tunneling-like effect in terms of the crisis-induced intermittency phenomenon. Further, we investigate the first passage times in this regime and observe the appearance of a Cantor-like fractal set in the initial history space, a characteristic feature of hyperbolic chaotic scattering. The non-integer value of the uncertainty dimension indicates that the residence time inside each well is unpredictable. Finally, we demonstrate the robustness of this tunneling intermittency as a function of the memory parameter by calculating the largest Lyapunov exponent.

4.
Cogn Emot ; 38(4): 587-604, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38329805

RESUMO

Decreased levels of positive affect (PA) are a hallmark of depression. Current models propose as potential main mechanisms a dysfunctional use of emotion regulation (ER) strategies (i.e. dampening, positive rumination), and a maladaptive activation of pro-hedonic goals. However, the role of these mechanisms in PA in daily life remains understudied. We used a 10-day ESM design to assess how these mechanisms influence each other and contribute to depressive symptomatology-related low momentary PA in 139 individuals. Higher depressive symptoms were associated with lower PA, pro-hedonic goals, more frequent use of positive rumination, and higher use of dampening. Further, experiencing higher levels of PA predicted lower following time point use of dampening in individuals with higher symptoms. Finally, using positive rumination was more beneficial (i.e. predicted higher PA increases one moment later) for individuals with higher symptomatology. Our findings suggest that moment-to-moment changes in PA daily life are affected by, and have an effect on, both pro-hedonic goals and the use of dampening and positive rumination, highlighting specific cognitive-affective mechanisms that should be considered when designing interventions aimed at improving low PA characterising depression symptomatology.


Assuntos
Afeto , Depressão , Regulação Emocional , Ruminação Cognitiva , Humanos , Feminino , Masculino , Depressão/psicologia , Adulto , Ruminação Cognitiva/fisiologia , Adulto Jovem , Avaliação Momentânea Ecológica , Objetivos , Pessoa de Meia-Idade
5.
Subst Use Misuse ; 59(1): 110-118, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37750391

RESUMO

Background: Brief therapies have proven to reduce tobacco cost-effectively, however, unsuccessful quit attempts remain notable in real-life conditions, and the underlying mechanisms of treatment success are still unclear. Objectives: We aimed to analyze the effectiveness of the Guided Self-Change (GSC) therapy combined with varenicline (VAR+T) in public health services against varenicline alone (VAR), and to identify mediators of treatment outcomes. We conducted a two-arm quasi-experimental study with 126 treatment-seeking smokers (age=57.3±9.1 years; 59.5% women). Before treatment, and at weeks 12 and 24, we assessed tobacco use and five potential mediators: withdrawal, craving, motivation to quit, anxiety, and depression. Results: Only 25% of participants adhered to varenicline prescription, and 54% to GSC therapy. VAR+T group showed a greater proportion of abstainers compared to VAR group at week 12 (75% vs 57.4%; φc=0.21) and week 24 (62.9% vs 52.5%; φc=0.10). When controlling for weeks taking varenicline, motivation showed a significant indirect effect over abstinence rates in VAR+T compared with VAR (a1b1=1.34; 95%CI=0.04, 5.03). Conclusions: The GSC effectiveness seems to increase motivation which in turn contributes to reducing tobacco use. The implementation of GSC therapy in public health services could minimize treatment duration and increase smoking abstinence in 'real-life' conditions where varenicline adherence remains low.


Assuntos
Abandono do Hábito de Fumar , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Vareniclina/uso terapêutico , Fumar , Resultado do Tratamento , Dispositivos para o Abandono do Uso de Tabaco
6.
Eur Arch Psychiatry Clin Neurosci ; 273(8): 1825-1835, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36920535

RESUMO

Individuals at clinical high risk (CHR) for psychosis exhibit altered facial emotion processing (FEP) and poor social functioning. It is unclear whether FEP deficits result from attentional biases, and further, how these abnormalities are linked to symptomatology (e.g., negative symptoms) and highly comorbid disorders that are also tied to abnormal FEP (e.g., depression). In the present study, we employed an eye-tracking paradigm to assess attentional biases and clinical interviews to examine differences between CHR (N = 34) individuals and healthy controls (HC; N = 46), as well as how such biases relate to symptoms and functioning in CHR individuals. Although no CHR-HC differences emerged in attentional biases, within the CHR group, symptoms and functioning were related to biases. Depressive symptoms were related to some free-view attention switching biases (e.g., to and from fearful faces, r = .50). Negative symptoms were related to more slowly disengaging from happy faces (r = .44), spending less time looking at neutral faces (r = - .42), and more time looking at no face (Avolition, r = .44). In addition, global social functioning was related to processes that overlapped with both depression and negative symptoms, including time looking at no face (r = - .68) and free-view attention switching with fearful faces (r = - .40). These findings are consistent with previous research, indicating that negative symptoms play a prominent role in the CHR syndrome, with distinct mechanisms relative to depression. Furthermore, the results suggest that attentional bias indices from eye-tracking paradigms may be predictive of social functioning.


Assuntos
Viés de Atenção , Transtornos Psicóticos , Humanos , Emoções , Atenção , Medo , Transtornos Psicóticos/complicações , Expressão Facial
7.
Am J Perinatol ; 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848044

RESUMO

OBJECTIVE: The aim of this research was to study the ways in which problems of adaptation to pregnancy influence the development of symptoms of perinatal depression via the presence of brooding and low maternal-fetal bonding, in addition to other risk factors previously established in the literature. STUDY DESIGN: Representative sample of pregnant women in the third trimester of gestation (N = 594) completed an online survey that included sociodemographic data and measures of perinatal depression, adjustment to pregnancy, bonding, and brooding. Other risk factors were also assessed as covariates, such as previous history of depression, generalized anxiety, perceived social support, and experience of stressful life events. Descriptive and correlational analyses were performed on the scores obtained by the subjects with the different instruments. A path model was formulated to establish the pathways through which adjustment influences perinatal depression symptomatology. On the one hand, the presence of brooding (worst adjustment to pregnancy → high brooding → perinatal depression symptomatology), and on the other hand, the quality of maternal-fetal bonding (worst adjustment to pregnancy → poor quality fetal-maternal bonding → perinatal depression symptomatology) would act as a mediator. RESULTS: The factors proposed by the literature were predictive of perinatal depressive symptomatology and the quality of adjustment to pregnancy. Problems adjusting to changes during pregnancy and experiencing it unsatisfactorily may predict individual differences in perinatal depressive symptoms. Significantly, this relationship was mediated by two key factors, the presence of brooding and low quality of the maternal-fetal bond. CONCLUSION: Our results provide evidence in favor of the existence of multiple paths through which difficulties in adapting to pregnancy can favor the occurrence of higher levels of perinatal depressive symptoms and identify new avenues for developing research in this area and preventive interventions empirically informed.

8.
J Adolesc ; 95(8): 1628-1640, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37563943

RESUMO

INTRODUCTION: Early adolescence represents a time of heightened vulnerability for depression. Negative interpretation biases have been associated with increases in depressive symptoms during this developmental period; however, the mechanisms underlying the association between interpretation biases and depression remain poorly understood. Cognitive theories posit that interpretation biases give rise to depression by modulating daily affect, particularly in the context of stress. However, this has not yet been directly examined. The present study tested affect intensity and instability as mechanisms linking negative interpretation biases with change in adolescent depressive symptoms. METHODS: Ninety-four adolescents (aged 11-13 years; 51% boys) from Vancouver, Canada, were recruited for this longitudinal study. At baseline (Time 1), participants self-reported depressive symptoms and completed the Scrambled Sentences Task to assess negative interpretation biases. Next, participants completed daily diaries to assess positive affect (PA) and negative affect (NA) during a naturalistic stressor-the first 2 weeks of high school (Time 2). Finally, participants self-reported depressive symptoms 3 months later (Time 3). Path models were conducted to test whether PA and NA intensity and instability mediated prospective associations between negative interpretation biases and depressive symptom changes. RESULTS: Although NA intensity, NA instability, and PA instability predicted increases in depressive symptoms, only NA intensity mediated associations between interpretation biases and symptom changes. Neither PA intensity nor instability mediated these associations. CONCLUSIONS: Elevated daily NA represents a specific mechanism through which stronger negative interpretation biases predict increases in depressive symptoms in adolescence.


Assuntos
Afeto , Depressão , Masculino , Humanos , Adolescente , Feminino , Depressão/psicologia , Estudos Longitudinais , Autorrelato , Viés , Canadá
9.
J Emerg Med ; 65(1): 1-6, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37385920

RESUMO

BACKGROUND: Urinary tract infections (UTI) due to multidrug-resistant bacteria are a frequent reason for visiting the emergency department (ED). OBJECTIVES: The aim of this study was to evaluate the applicability of a predictive model of infection by multidrug-resistant microorganisms in UTIs treated in an ED. METHODS: This is a retrospective observational study. Adult patients admitted to an ED with a diagnosis of UTI and positive urine culture were included. The main objective was to evaluate the area under the curve of the receiver operating characteristic (AUC-ROC), the scale proposed by González-del-Castillo, considering infection by a resistant pathogen as the dependent variable and the scale score of the predictive model used as the independent variable. RESULTS: The study included 414 patients with UTIs, 125 (30.2%) of which were caused by multidrug-resistant microorganisms. A total of 38.4% of patients were treated with antibiotics during the previous 3 months and a multidrug-resistant pathogen was isolated from 10.4% of the total during the previous 6 months. The AUC-ROC of the scale for predicting UTIs due to multidrug-resistant microorganisms was 0.79 (95% confidence interval 0.76-0.83), the optimal cut-off point being 9 points, with a sensitivity of 76.8% and a specificity of 71.6%. CONCLUSIONS: The use of the predictive model evaluated is a useful tool in real clinical practice to improve the success of empirical treatment of patients presenting to the ED with a diagnosis of UTI and positive urine culture pending identification.


Assuntos
Infecções Urinárias , Adulto , Humanos , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Serviço Hospitalar de Emergência , Bactérias
10.
Telemed J E Health ; 29(2): 278-283, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35727139

RESUMO

Introduction: The emergence or persistence of symptoms after acute SARS-CoV-2 infection has made it necessary to develop tools to detect them and assess their impact on patients' quality of life. One of these tools is the COVID-19 Yorkshire Rehabilitation Screening (C19-YRS) scale. We present the results of this tool in a cohort of first pandemic wave patients. Methods: A cross-sectional study of patients with confirmed SARS-CoV-2 infection from March to May 2020 in Lugo (northwestern Spain). C19-YRS was administered via phone 10 months after the acute infection to both former inpatients and outpatients. Electronic medical records were reviewed and relevant data from the acute episode were collected. The main outcome was the presence of impairment in different areas measured by the C19-YRS scale. Results: The answer rate was 63.2%. The mean age was 54 ± 16 years, 38.4% were male and 190 (42.9%) had some comorbidity. Eighty-seven patients (19.6%) required hospitalization and 10 (2.3%) required intensive care unit admission. Ten (3.5%) patients lost their job due to the pandemic. Two hundred seventy-six patients (62.3%) related any symptoms; fatigue (37.2%) and exertional dyspnea (33.4%) were the most common with significant worsening in both cases compared with the situation before the infection. Subgroup analysis showed that more symptom domains were impaired in women than men. Older patients, those with comorbidity and those who needed hospital admission, demanded more health resources after the acute infection. Discussion: C19-YRS is useful for the detection and quantification of symptoms after COVID-19 and provides relevant social, health, and occupational information.


Assuntos
COVID-19 , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , SARS-CoV-2 , Pandemias , Espanha , Qualidade de Vida , Estudos Transversais
11.
Respir Res ; 23(1): 323, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36419130

RESUMO

BACKGROUND: Influenza viruses cause seasonal epidemics worldwide with a significant morbimortality burden. Clinical spectrum of Influenza is wide, being respiratory failure (RF) one of its most severe complications. This study aims to elaborate a clinical prediction rule of RF in hospitalized Influenza patients. METHODS: A prospective cohort study was conducted during two consecutive Influenza seasons (December 2016-March 2017 and December 2017-April 2018) including hospitalized adults with confirmed A or B Influenza infection. A prediction rule was derived using logistic regression and recursive partitioning, followed by internal cross-validation. External validation was performed on a retrospective cohort in a different hospital between December 2018 and May 2019. RESULTS: Overall, 707 patients were included in the derivation cohort and 285 in the validation cohort. RF rate was 6.8% and 11.6%, respectively. Chronic obstructive pulmonary disease, immunosuppression, radiological abnormalities, respiratory rate, lymphopenia, lactate dehydrogenase and C-reactive protein at admission were associated with RF. A four category-grouped seven point-score was derived including radiological abnormalities, lymphopenia, respiratory rate and lactate dehydrogenase. Final model area under the curve was 0.796 (0.714-0.877) in the derivation cohort and 0.773 (0.687-0.859) in the validation cohort (p < 0.001 in both cases). The predicted model showed an adequate fit with the observed results (Fisher's test p > 0.43). CONCLUSION: we present a simple, discriminating, well-calibrated rule for an early prediction of the development of RF in hospitalized Influenza patients, with proper performance in an external validation cohort. This tool can be helpful in patient's stratification during seasonal Influenza epidemics.


Assuntos
Influenza Humana , Linfopenia , Insuficiência Respiratória , Adulto , Humanos , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Estudos Retrospectivos , Estudos Prospectivos , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/epidemiologia , Insuficiência Respiratória/complicações , Linfopenia/complicações , Lactato Desidrogenases
12.
Chembiochem ; 22(4): 645-651, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-32991020

RESUMO

Transcription-activator-like effectors (TALEs) are repeat-based, programmable DNA-binding proteins that can be engineered to recognize sequences of canonical and epigenetically modified nucleobases. Fluorescent TALEs can be used for the imaging-based analysis of cellular 5-methylcytosine (5 mC) in repetitive DNA sequences. This is based on recording fluorescence ratios from cell co-stains with two TALEs: an analytical TALE targeting the cytosine (C) position of interest through a C-selective repeat that is blocked by 5 mC, and a control TALE targeting the position with a universal repeat that binds both C and 5 mC. To enhance this approach, we report herein the development of novel 5 mC-selective repeats and their integration into TALEs that can replace universal TALEs in imaging-based 5 mC analysis, resulting in a methylation-dependent response of both TALEs. We screened a library of size-reduced repeats and identified several 5 mC binders. Compared to the 5 mC-binding repeat of natural TALEs and to the universal repeat, two repeats containing aromatic residues showed enhancement of 5 mC binding and selectivity in cellular transcription activation and electromobility shift assays, respectively. In co-stains of cellular SATIII DNA with a corresponding C-selective TALE, this selectivity results in a positive methylation response of the new TALE, offering perspectives for studying 5 mC functions in chromatin regulation by in situ imaging with increased dynamic range.


Assuntos
5-Metilcitosina/análise , Metilação de DNA , Processamento de Imagem Assistida por Computador/métodos , Sondas Moleculares/metabolismo , Sequências Repetitivas de Ácido Nucleico , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Engenharia Genética , Células HEK293 , Humanos , Sondas Moleculares/química , Efetores Semelhantes a Ativadores de Transcrição/química
13.
J Sleep Res ; 30(4): e13233, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33200511

RESUMO

The electroencephalographic signal constitutes the main sign classically used for the identification of states of alertness. However, activities in the high frequency (>100 Hz) range have not been properly studied despite their high potential for sleep scoring in rodents. In the present study, we designed a method for the identification of the sleep-wake states in rats by exclusively using high-frequency activities of the electroencephalogram. By calculating the ratio between the amplitude of the electroencephalographic signal from 110 to 200 Hz and from 110 to 300 Hz, we obtained an index that had values that were low during wakefulness, intermediate during non-REM sleep and high during REM sleep. This high-frequency index (HiFI) allowed the identification of each state without the need to study other signs such as muscle activity or eye movements. To evaluate the performance of the index, we compared it with the conventional scoring of the sleep-wake cycle based upon the study of the electromyogram and delta (0.5-4 Hz), theta (6-9 Hz) and sigma (10-14 Hz) bands of the electroencephalogram. The index had an accuracy of 90.43 ± 1.91% (Cohen's kappa value of 0.82), confirming that the study of the high-frequency activities of the electroencephalogram was sufficient to reliably identify alertness states in the rat. Compared to other sleep-scoring methods, the HiFI has several advantages. It only requires one electroencephalography electrode, thus reducing the severity of the surgical preparation of the experimental animal, and its calculation is very simple, so it can be easily implemented online to classify sleep-wake states in real time.


Assuntos
Eletroencefalografia , Sono/fisiologia , Vigília/fisiologia , Animais , Eletromiografia , Feminino , Masculino , Ratos , Ratos Wistar , Sono REM
14.
Eur J Clin Microbiol Infect Dis ; 40(12): 2623-2626, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33987802

RESUMO

Cryptococcosis is a fungal infection that is rarely reported in patients without human immunodeficiency virus (HIV) infection, especially when the central nervous system (CNS) or pulmonary system is not involved. We report a case of isolated colonic cryptococcosis without disseminated disease in a 64-year-old immunocompetent woman without HIV infection who presented with chronic diarrhea and no episodes of fever or weight loss. The diagnosis was based on histopathology examination. Furthermore, we performed a literature review showing that few reports have been published so far and in the case of colonic cryptococcal infection, the prognosis is favorable among HIV-uninfected patients.


Assuntos
Antifúngicos/administração & dosagem , Colo/microbiologia , Criptococose/microbiologia , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Criptococose/imunologia , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/genética , Cryptococcus neoformans/isolamento & purificação , Cryptococcus neoformans/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade
15.
Macromol Rapid Commun ; 42(3): e2000538, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33244816

RESUMO

The preparation of non-isocyanate polyurethanes (NIPUs) by polyaddition of (poly)cyclic carbonates to (poly)amines represents one of the most optimistic alternatives for replacing conventional polyurethanes prepared by the toxic isocyanate chemistry. However, the limited reactivity of conventional five membered cyclic carbonates even in the presence of catalysts restricts their industrial implementation. One way to mitigate this lack of reactivity is to combine with other chemistries to create hybrid-NIPUs with superior performance. In this article the combination of the adhesive promoter, dopamine, and the fast-curing promoter, an aminopropyl trimethoxysilane, is found to create a synergetic effect on the rheological and adhesive properties of NIPUs. After demonstrating the importance of adjusting soft/hard ratios to obtain lap-shear strength adhesion values up to 21 MPa on stainless steel, these values are retained when adding dopamine and silane compounds. Importantly, the adhesive properties of NIPU are preserved at high temperature (T > 200 °C) for optimal compositions. Finally, adhesion tests on various substrates (polyamide, high density polyethylene, poly(methyl methacrylate), oak wood, and aluminum) show best performances on polar substrates confirming the strong interactions of hydroxyl groups of NIPU and dopamine.


Assuntos
Isocianatos , Poliuretanos , Adesivos , Dopamina , Resistência ao Cisalhamento
16.
Chaos ; 31(1): 013104, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33754771

RESUMO

We consider a hydrodynamic model of a quantum dusty plasma. We prove mathematically that the resulting dust ion-acoustic plasma waves present the property of being conservative on average. Furthermore, we test this property numerically, confirming its validity. Using standard techniques from the study of dynamical systems, as, for example, the Lyapunov characteristic exponents, we investigate the chaotic dynamics of the plasma and show numerically its existence for a wide range of parameter values. Finally, we illustrate how chaotic dynamics organizes in the parameter space for fixed values of the initial conditions, as the Mach number and the quantum diffraction parameter are continuously varied.

17.
J Strength Cond Res ; 35(6): 1766-1772, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557176

RESUMO

ABSTRACT: Martín-López, Á, Mendes, RS, and Castillo-Rodríguez, A. Internal and external loads in training week before the competition in U19 high-level soccer players. J Strength Cond Res 35(6): 1766-1772, 2021-Nowadays, the information about the load in training sessions (TRs) and the relationship of these TRs with official competition are necessary to gain the sport success in soccer. The aim of this study was to quantify the different loads in TRs according to days before the competition (P-4, P-2, and P-1) on soccer players U19 based on their playing position and their sport success. Twenty-four male Spanish high-level players (age: 16.5 ± 0.5 years; height: 1.69 ± 0.04 m; and body mass: 63.0 ± 6.3 kg) participated in the study. They were grouped according to their playing position: external defenders, internal defenders (ID), external midfielders, internal midfielders (IM), and forwards (FO). To conduct the study, global positioning system technology was used, and a 1-way analysis of variance and Pearson correlation were performed. The main results revealed that the highest physical and physiological responses in the TRs were shown by ID, IM, and players without sport success (p < 0.05), and during P-2. In addition, sport success is predicted by the mean heart rate (R2 = 0.33; p < 0.001). As conclusion, players covering central positions in the playing field performed higher physical and physiological demands than players covering exterior or forward positions. Furthermore, physical and physiological responses during the TRs P-2 may be similar to the responses produced in competition match and are notably different depending on the sport success of the soccer player.


Assuntos
Desempenho Atlético , Corrida , Futebol , Adolescente , Sistemas de Informação Geográfica , Humanos , Masculino , Exame Físico
18.
Angew Chem Int Ed Engl ; 60(24): 13507-13512, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826797

RESUMO

5-Methylcytosine (5mC), the central epigenetic mark of mammalian DNA, plays fundamental roles in chromatin regulation. 5mC is written onto genomes by DNA methyltransferases (DNMT), and perturbation of this process is an early event in carcinogenesis. However, studying 5mC functions is limited by the inability to control individual DNMTs with spatiotemporal resolution in vivo. We report light-control of DNMT catalysis by genetically encoding a photocaged cysteine as a catalytic residue. This enables translation of inactive DNMTs, their rapid activation by light-decaging, and subsequent monitoring of de novo DNA methylation. We provide insights into how cancer-related DNMT mutations alter de novo methylation in vivo, and demonstrate local and tuneable cytosine methylation by light-controlled DNMTs fused to a programmable transcription activator-like effector domain targeting pericentromeric satellite-3 DNA. We further study early events of transcriptome alterations upon DNMT-catalyzed cytosine methylation. Our study sets a basis to dissect the order and kinetics of diverse chromatin-associated events triggered by normal and aberrant DNA methylation.


Assuntos
DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/efeitos da radiação , Luz , 5-Metilcitosina/metabolismo , Biocatálise , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferases/química , DNA (Citosina-5-)-Metiltransferases/genética , Células HEK293 , Humanos , Mutação , Transcriptoma/efeitos da radiação
19.
J Am Chem Soc ; 142(16): 7289-7294, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32286069

RESUMO

Ten-eleven-translocation (TET) dioxygenases catalyze the oxidation of 5-methylcytosine (5mC), the central epigenetic regulator of mammalian DNA. This activity dynamically reshapes the epigenome and transcriptome by depositing oxidized 5mC derivatives and initiating active DNA demethylation. However, studying this dynamic is hampered by the inability to selectively activate individual TETs with temporal control in cells. We report activation of TETs in mammalian cells by incorporation of genetically encoded 4,5-dimethoxy-2-nitrobenzyl-l-serine as a transient active-site block, and its subsequent deprotection with light. Our approach enables precise insights into the impact of cancer-associated TET2 mutations on the kinetics of TET2 catalysis in vivo, and allows time-resolved monitoring of target gene activation and transcriptome reorganization. This sets a basis for dissecting the order and kinetics of chromatin-associated events triggered by TET catalysis, ranging from DNA demethylation to chromatin and transcription regulation.


Assuntos
5-Metilcitosina/metabolismo , Dioxigenases/metabolismo , Humanos , Oxirredução , Transcriptoma
20.
Ann Rheum Dis ; 79(9): 1170-1173, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32532753

RESUMO

BACKGROUND: The susceptibility of patients with rheumatic diseases and the risks or benefits of immunosuppressive therapies for COVID-19 are unknown. METHODS: We performed a retrospective study with patients under follow-up in rheumatology departments from seven hospitals in Spain. We matched updated databases of rheumatology patients with severe acute respiratory syndrome coronavirus 2-positive PCR tests performed in the hospital to the same reference populations. Rates of PCR+ confirmed COVID-19 were compared among groups. RESULTS: Patients with chronic inflammatory diseases had 1.32-fold higher prevalence of hospital PCR+ COVID-19 than the reference population (0.76% vs 0.58%). Patients with systemic autoimmune or immune-mediated disease (AI/IMID) showed a significant increase, whereas patients with inflammatory arthritis (IA) or systemic lupus erythematosus did not. COVID-19 cases in some but not all diagnostic groups had older ages than cases in the reference population. Patients with IA on targeted-synthetic or biological disease-modifying antirheumatic drugs (DMARDs), but not those on conventional-synthetic DMARDs, had a greater prevalence despite a similar age distribution. CONCLUSION: Patients with AI/IMID show a variable risk of hospital-diagnosed COVID-19. Interplay of ageing, therapies and disease-specific factors seem to contribute. These data provide a basis to improve preventive recommendations to rheumatic patients and to analyse the specific factors involved in COVID-19 susceptibility.


Assuntos
Doenças Autoimunes/epidemiologia , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Hospitalização/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Doenças Reumáticas/epidemiologia , Adulto , Distribuição por Idade , Idoso , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/virologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/virologia , COVID-19 , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/virologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase , Prevalência , Estudos Retrospectivos , Doenças Reumáticas/tratamento farmacológico , Doenças Reumáticas/virologia , SARS-CoV-2 , Espanha/epidemiologia
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