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Distrust in scientific expertise1-14 is dangerous. Opposition to vaccination with a future vaccine against SARS-CoV-2, the causal agent of COVID-19, for example, could amplify outbreaks2-4, as happened for measles in 20195,6. Homemade remedies7,8 and falsehoods are being shared widely on the Internet, as well as dismissals of expert advice9-11. There is a lack of understanding about how this distrust evolves at the system level13,14. Here we provide a map of the contention surrounding vaccines that has emerged from the global pool of around three billion Facebook users. Its core reveals a multi-sided landscape of unprecedented intricacy that involves nearly 100 million individuals partitioned into highly dynamic, interconnected clusters across cities, countries, continents and languages. Although smaller in overall size, anti-vaccination clusters manage to become highly entangled with undecided clusters in the main online network, whereas pro-vaccination clusters are more peripheral. Our theoretical framework reproduces the recent explosive growth in anti-vaccination views, and predicts that these views will dominate in a decade. Insights provided by this framework can inform new policies and approaches to interrupt this shift to negative views. Our results challenge the conventional thinking about undecided individuals in issues of contention surrounding health, shed light on other issues of contention such as climate change11, and highlight the key role of network cluster dynamics in multi-species ecologies15.
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Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Internacionalidad , Pandemias/prevención & control , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Opinión Pública , Medios de Comunicación Sociales/estadística & datos numéricos , Vacunación/psicología , Algoritmos , COVID-19 , Vacunas contra la COVID-19 , Análisis por Conglomerados , Infecciones por Coronavirus/psicología , Humanos , Factores de Tiempo , Vacunas ViralesRESUMEN
We explore ultrafast charge transfer (CT) resonantly induced by hard X-ray radiation in organic thiophene-based polymers at the sulfur K-edge. A combination of core-hole clock spectroscopy with real-time propagation time-dependent density functional theory simulations gives an insight into the electron dynamics underlying the CT process. Our method provides control over CT by a selective excitation of a specific resonance in the sulfur atom with monochromatic X-ray radiation. Our combined experimental and theoretical investigation establishes that the dominant mechanism of CT in polymer powders and films consists of electron delocalisation along the polymer chain occurring on the low-femtosecond time scale.
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Excited double-core-hole states of isolated water molecules resulting from the sequential absorption of two x-ray photons have been investigated. These states are formed through an alternative pathway, where the initial step of core ionization is accompanied by the shake-up of a valence electron, leading to the same final states as in the core-ionization followed by core-excitation pathway. The capability of the x-ray free-electron laser to deliver very intense, very short, and tunable light pulses is fully exploited to identify the two different pathways.
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Objectives. To understand changes in how Facebook pages frame vaccine opposition.Methods. We categorized 204 Facebook pages expressing vaccine opposition, extracting public posts through November 20, 2019. We analyzed posts from October 2009 through October 2019 to examine if pages' content was coalescing.Results. Activity in pages promoting vaccine choice as a civil liberty increased in January 2015, April 2016, and January 2019 (t[76] = 11.33 [P < .001]; t[46] = 7.88 [P < .001]; and t[41] = 17.27 [P < .001], respectively). The 2019 increase was strongest in pages mentioning US states (t[41] = 19.06; P < .001). Discussion about vaccine safety decreased (rs[119] = -0.61; P < .001) while discussion about civil liberties increased (rs[119] = 0.33; Py < .001]). Page categories increasingly resembled one another (civil liberties: rs[119] = -0.50 [P < .001]; alternative medicine: rs[84] = -0.77 [P < .001]; conspiracy theories: rs[119] = -0.46 [P < .001]; morality: rs[106] = -0.65 [P < .001]; safety and efficacy: rs[119] = -0.46 [P < .001]).Conclusions. The "Disneyland" measles outbreak drew vaccine opposition into the political mainstream, followed by promotional campaigns conducted in pages framing vaccine refusal as a civil right. Political mobilization in state-focused pages followed in 2019.Public Health Implications. Policymakers should expect increasing attempts to alter state legislation associated with vaccine exemptions, potentially accompanied by fiercer lobbying from specific celebrities.
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Movimiento Anti-Vacunación , Derechos Civiles , Brotes de Enfermedades , Sarampión/epidemiología , Medios de Comunicación Sociales , Negativa a la Vacunación , California/epidemiología , Humanos , Vacuna Antisarampión/administración & dosificación , Salud Pública , Estados Unidos/epidemiologíaRESUMEN
Iron centered N-heterocyclic carbene (Fe-NHC) complexes have shown long-lived excited states with charge transfer character useful for light harvesting applications. Understanding the nature of the metal-ligand bond is of fundamental importance to rationally tailor the properties of transition metal complexes. The high-energy-resolution fluorescence detected X-ray absorption near edge structure (HERFD-XANES) has been used to probe the valence orbitals of three carbene complexes, [FeII(bpy)(btz)2](PF6)2 (bpy = 2,2'-bipyridine, btz = 3,3'-dimethyl-1,1'-bis(p-tolyl)-4,4'-bis(1,2,3-triazol-5-ylidene)), [FeIII(btz)3](PF6)3, and [FeIII(phtmeimb)2]PF6 (phtmeimb = [phenyl(tris(3-methylimidazol-2-ylidene))borate]-). The multiconfigurational restrict active space (RAS) approach has been used to simulate the metal K pre-edge X-ray absorption spectroscopy of these carbene complexes, and have reproduced the metal K pre-edge spectral features in terms of relative intensity and peak positions. The evident intensity difference between the FeII and the other two FeIII complexes has been elucidated with different intensity mechanisms in the transition. The smaller splitting between the t2g and eg character peak for [FeIII(btz)3](PF6)3 has been observed in the experimental measurements and been reproduced in the RAS calculations. The results show how the combination of experimental HERFD-XANES measurements and ab initio RAS simulations can give quantitative evaluation of the orbital interactions between metal and ligands for such large and strongly interacting systems and thus allow to understand and predict properties of novel complexes.
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Introduction: Caffeine is a widely used ergogenic aid in society, which has made it a topic of interest due to its various benefits at cognitive, physiological, and sports levels, among others. This review aims to investigate the potential benefits of caffeine supplementation in psychophysiological performance through a structured search in the SportsDiscus/Scopus/MEDLINE and Web of Science databases (October 2022). This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guideline, and the inclusion criteria were defined based on the PICOS model. Double-blind, randomized/semi-randomized crossover articles comparing caffeine intake with an identical placebo condition were included. Filters by age or gender of the participants were not applied. The initial search gave a result of 201 articles, which after eliminating duplicates and applying the inclusion and exclusion criteria, the final sample for this review was 8 studies. The review concluded that 3 (37.5 %) found favorable ergogenic effects, 4 (50 %) found partial effects, and 1 (12.5 %) found no effects of caffeine supplementation on variables related to psychophysiological performance. In general, both partial and negative results could be linked to insufficient doses to produce any change, likewise, habitual caffeine consumption is also a variable that could be attenuating its potential ergogenic effect. In conclusion, moderate doses of caffeine 3-6 mg/kg seem to be an effective strategy to improve the psychophysiological response in various contexts without generating detrimental effects on performance, as long as the intervention designs consider the variables that could condition its effect.
Introducción: La cafeína es una ayuda ergogénica de amplio uso en la sociedad, lo que la ha convertido en un tema de interés por sus diversos beneficios a nivel cognitivo, fisiológico y deportivo, entre otros. Esta revisión tiene como objetivo investigar los beneficios potenciales de la suplementación de cafeína sobre el rendimiento psicofisiológico a través de una búsqueda estructurada en las bases de datos SportsDiscus/Scopus/MEDLINE y Web of Science (octubre de 2022). Esta revisión siguió la guía Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) y los criterios de inclusión se definieron en función del modelo PICOS. Se incluyeron artículos doble ciego, cruzados y aleatorizados/semialeatorizados en donde se comparó la ingesta de cafeína con una condición idéntica de placebo. No se aplicaron filtros por edad ni sexo de los participantes. La búsqueda inicial dio un resultado de 201 artículos, los cuales, después de eliminar los duplicados y aplicar los criterios de inclusión y exclusión, dieron una muestra final para esta revisión de 8 estudios. La revisión concluyo que 3 (37,5 %) encontraron efectos ergogénicos favorables, 4 (50 %) encontraron efectos parciales y 1 (12,5 %) no encontró efectos de la suplementación de cafeína sobre las variables relacionadas con el rendimiento psicofisiológico. En general, los resultados tanto parciales como negativos podrían estar ligados a dosis insuficientes para producir algún cambio; de igual forma, el consumo habitual de cafeína también es una variable que podría estar atenuando su potencial efecto ergogénico. En conclusión, dosis moderadas de cafeína de 3-6 mg/kg parecen ser una estrategia eficaz para mejorar la respuesta psicofisiológica en diversos contextos, sin generar efectos perjudiciales en el rendimiento, siempre y cuando los diseños de intervención consideren las variables que podrían condicionar su efecto.
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Rendimiento Atlético , Cafeína , Cafeína/farmacología , Humanos , Rendimiento Atlético/psicología , Sustancias para Mejorar el Rendimiento/farmacología , Sustancias para Mejorar el Rendimiento/administración & dosificación , Suplementos Dietéticos , Psicofisiología , Estimulantes del Sistema Nervioso Central/farmacología , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
We have built and commissioned a novel standalone multi-crystal x-ray spectrometer (MOSARIX) in the von Hamos configuration based on highly annealed pyrolytic graphite crystals. The spectrometer is optimized for the energy range of 2-5 keV, but this range can be extended up to 20 keV by using higher reflection orders. With its nine crystals and a Pilatus detector, MOSARIX achieves exceptional detection efficiency with good resolving power (better than 4000), opening the door to study small cross section phenomena and perform fast in situ measurements. The spectrometer operates under a He atmosphere, which provides a flexible sample environment for measurements in gas, liquid, and solid phases.
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Resonant inelastic x-ray scattering (RIXS) is a major method for investigation of electronic structure and dynamics, with applications ranging from basic atomic physics to materials science. In RIXS applied to inversion-symmetric systems, it has generally been accepted that strict parity selectivity applies in the sub-kilo-electron volt region. In contrast, we show that the parity selection rule is violated in the RIXS spectra of the free homonuclear diatomic O2 molecule. By analyzing the spectral dependence on scattering angle, we demonstrate that the violation is due to the phase difference in coherent scattering at the two atomic sites, in analogy with Young's double-slit experiment. The result also implies that the interpretation of x-ray absorption spectra for inversion symmetric molecules in this energy range must be revised.
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Online hate speech is a critical and worsening problem, with extremists using social media platforms to radicalize recruits and coordinate offline violent events. While much progress has been made in analyzing online hate speech, no study to date has classified multiple types of hate speech across both mainstream and fringe platforms. We conduct a supervised machine learning analysis of 7 types of online hate speech on 6 interconnected online platforms. We find that offline trigger events, such as protests and elections, are often followed by increases in types of online hate speech that bear seemingly little connection to the underlying event. This occurs on both mainstream and fringe platforms, despite moderation efforts, raising new research questions about the relationship between offline events and online speech, as well as implications for online content moderation.
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Odio , Medios de Comunicación Sociales , Humanos , Agresión , HablaRESUMEN
A huge amount of potentially dangerous COVID-19 misinformation is appearing online. Here we use machine learning to quantify COVID-19 content among online opponents of establishment health guidance, in particular vaccinations ("anti-vax"). We find that the anti-vax community is developing a less focused debate around COVID-19 than its counterpart, the pro-vaccination ("pro-vax") community. However, the anti-vax community exhibits a broader range of "flavors" of COVID-19 topics, and hence can appeal to a broader cross-section of individuals seeking COVID-19 guidance online, e.g. individuals wary of a mandatory fast-tracked COVID-19 vaccine or those seeking alternative remedies. Hence the anti-vax community looks better positioned to attract fresh support going forward than the pro-vax community. This is concerning since a widespread lack of adoption of a COVID-19 vaccine will mean the world falls short of providing herd immunity, leaving countries open to future COVID-19 resurgences. We provide a mechanistic model that interprets these results and could help in assessing the likely efficacy of intervention strategies. Our approach is scalable and hence tackles the urgent problem facing social media platforms of having to analyze huge volumes of online health misinformation and disinformation.
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Split-belt treadmills that move the legs at different speeds are thought to update internal representations of the environment, such that this novel condition generates a new locomotor pattern with distinct spatio-temporal features compared to those of regular walking. It is unclear the degree to which such recalibration of movements in the spatial and temporal domains is interdependent. In this study, we explicitly altered subjects' limb motion in either space or time during split-belt walking to determine its impact on the adaptation of the other domain. Interestingly, we observed that motor adaptation in the spatial domain was susceptible to altering the temporal domain, whereas motor adaptation in the temporal domain was resilient to modifying the spatial domain. This non-reciprocal relation suggests a hierarchical organization such that the control of timing in locomotion has an effect on the control of limb position. This is of translational interest because clinical populations often have a greater deficit in one domain compared to the other. Our results suggest that explicit changes to temporal deficits cannot occur without modifying the spatial control of the limb.
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Many high-profile societal problems involve an individual or group repeatedly attacking another - from child-parent disputes, sexual violence against women, civil unrest, violent conflicts and acts of terror, to current cyber-attacks on national infrastructure and ultrafast cyber-trades attacking stockholders. There is an urgent need to quantify the likely severity and timing of such future acts, shed light on likely perpetrators, and identify intervention strategies. Here we present a combined analysis of multiple datasets across all these domains which account for >100,000 events, and show that a simple mathematical law can benchmark them all. We derive this benchmark and interpret it, using a minimal mechanistic model grounded by state-of-the-art fieldwork. Our findings provide quantitative predictions concerning future attacks; a tool to help detect common perpetrators and abnormal behaviors; insight into the trajectory of a 'lone wolf'; identification of a critical threshold for spreading a message or idea among perpetrators; an intervention strategy to erode the most lethal clusters; and more broadly, a quantitative starting point for cross-disciplinary theorizing about human aggression at the individual and group level, in both real and online worlds.
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Agresión , Conflicto Psicológico , Modelos Teóricos , Conjuntos de Datos como Asunto , HumanosRESUMEN
Resumen El artículo buscó comprobar que un uso inadecuado de la información en medios de comunicación puede incrementar riesgos en personas susceptibles a enfermedades mentales. Para ello, se estudió el efecto de noticias colombianas, tanto nacionales como regionales, que se relacionaban con la palabra suicidio en el 2014. Posteriormente, se analizaron las noticias, aplicando una encuesta con ocho preguntas por parte de dos integrantes del grupo, entrenados previamente para la realización de la investigación, a fin de ir más a fondo y ver el efecto de los medios de comunicación y su estigmatización. Hoy en día, los adolescentes se ven más expuestos a situaciones que pueden afectar su estado de ánimo por un uso inadecuado de medios de comunicación, teniendo en cuenta que el peor desenlace sería llevar a una conducta suicida.
Abstract The article attempts to verify that inappropriate use of information provided by the media can increase risks for persons who are susceptible to mental illness. The impact of Colombian news in 2014 (national and regional) related to the word suicide was studied to that end. The news was analyzed subsequently through a survey with eight questions applied by two members of the group who had been trained to conduct the study. The idea was to delve deeper and to see the effect of the media and its stigmatization. Nowadays, adolescents are more exposed to situations in which their mood can be affected by improper use of the media, bearing in mind that the worst outcome would be that it leads to suicidal behavior.
Resumo Este artigo procurou comprovar que um uso inadequado da informação em meios de comunicação pode gerar riscos em pessoas suscetíveis a doença mental. Para isso, estudou-se o efeito de notícias colombianas, tanto nacionais como regionais, que se relacionavam com a palavra suicídio, em 2014. Em seguida, analisaram-se as notícias aplicando uma pesquisa com oito perguntas por parte de dois integrantes do grupo, treinados para a realização da pesquisa, a fim de ir mais a fundo e ver o efeito dos meios de comunicação e sua estigmatização. Atualmente, os adolescentes se veem mais expostos a situações que podem afetar seu humor por um uso inadequado de meios de comunicação, considerando que o pior desfecho seria levar a um comportamento suicida.
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Humanos , Suicidio , Enfermedad , Adolescente , Medios de Comunicación , DepresiónRESUMEN
La diabetes gestacional (DG) es una de las complicaciones médicas que más frecuentemente afectan a las mujeres embarazadas; algunos autores reportan una prevalencia entre el 9,7 y el 13,9%. La DG puede ser causa de efectos adversos como: nacimiento pretérmino, macrosomia, nacimiento por cesárea, hiperbilirrubinemia, hipertensión gestacional, así como la predisposición de desarrollar posteriormente diabetes mellitus tipo 2 y síndrome metabólico. La literatura señala la asociación entre los microorganismos presentes en el biofilm subgingival, etiológicos de la inflamación de los tejidos de soporte dentarios y diabetes mellitus. Uno de estos microorganismos, Porphyromonas gingivalis, expresa, entre otros factores de virulencia, una proteína llamada fimbrilina, la cual presenta variaciones genotípicas relacionadas con su capacidad de inducción en la expresión de mediadores inflamatorios; los genotipos fimA II y fimA IV se consideran con mayor capacidad de virulencia y su presencia se ha asociado con la resistencia a la insulina. En este estudio analizamos la prevalencia de los genotipos fimA II y fimA IV en un grupo de mujeres mexicanas de la región central de México con DG, en mujeres con embarazo sin diabetes y mujeres sin embarazo y sin diabetes. Los resultados encontrados muestran una elevada presencia del genotipo fimA II en mujeres con DG (p < 0,05)
Gestational diabetes (GD) is one of the most common complications in pregnant women, with some authors reporting prevalence between 9.7% and 13.9%. GD can lead to the following adverse effects: preterm birth, macrosomia, cesarean birth, hyperbilirubinemia, gestational hypertension, and predisposition to later develop diabetes mellitus type 2 and metabolic syndrome. The literature shows an association between microorganisms in the subgingival biofilm, which produces inflammation of the dental support tissue, and diabetes mellitus. Porphyromonasgingivalis is one of these microorganisms, and among other virulence factors, it expresses a protein called fimbrilin which has genotypic variations related to its ability to induce expression of inflammatory mediators. Genotypes fimA II and fimA IV are considered to have a greater virulence and their presence has been associated with insulin resistance. An analysis is made on the prevalence of genotypes fimA II and fimA IV in a group of women in central region of Mexico with GD, pregnant women without diabetes, and non-pregnant women without diabetes. The results show an elevated presence of genotype fimA II in women with GD (P <.05)
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Humanos , Femenino , Embarazo , Adulto , Diabetes Gestacional , Infecciones por Bacteroidaceae/epidemiología , Porphyromonas gingivalis , Porphyromonas gingivalis/genética , Proteínas Fimbrias/genética , Mujeres Embarazadas , Genotipo , Epidemiología Descriptiva , Prevalencia , Estudios Transversales , Estudio Observacional , MéxicoRESUMEN
Atualmente um número considerável de pacientes adultos submete-se a diversos procedimentos ortodônticos. A maioria destes pacientes apresentam algumas restauraçöes confeccionadas com diferentes tipos de materiais, porém o ortodontista deve conhecer as técnicas e os materiais que viabilizam a colagem de braquetes sobre diferentes substratos. Neste artigo descreve-se a técnica de colagem de braquetes sobre dentes metálicos utilizando o Typodont