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The protein dynamical transition marks an increase in atomic mobility and the onset of anharmonic motions at a critical temperature (T d), which is considered relevant for protein functionality. This phenomenon is ubiquitous, regardless of protein composition, structure and biological function and typically occurs at large protein content, to avoid water crystallization. Recently, a dynamical transition has also been reported in non-biological macromolecules, such as poly(N-isopropyl acrylamide) (PNIPAM) microgels, bearing many similarities to proteins. While the generality of this phenomenon is well-established, the role of water in the transition remains a subject of debate. In this study, we use atomistic molecular dynamics (MD) simulations and elastic incoherent neutron scattering (EINS) experiments with selective deuteration to investigate the microscopic origin of the dynamical transition and distinguish water and PNIPAM roles. While a standard analysis of EINS experiments would suggest that the dynamical transition occurs in PNIPAM and water at a similar temperature, simulations reveal a different perspective, also qualitatively supported by experiments. From room temperature down to about 180 K, PNIPAM exhibits only modest changes of dynamics, while water, being mainly hydration water under the probed extreme confinement, significantly slows down and undergoes a mode-coupling transition from diffusive to activated. Our findings therefore challenge the traditional view of the dynamical transition, demonstrating that it occurs in proximity of the water mode-coupling transition, shedding light on the intricate interplay between polymer and water dynamics.
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Human information processing is not always rational but influenced by prior attitudes, a phenomenon commonly known as motivated reasoning. We conducted two studies (N1 = 556, N2 = 1198; UK samples) investigating motivated reasoning in the context of climate change with a focus on individual differences as potential moderating factors. While previous research investigated motivated reasoning regarding the debate whether climate change is anthropogenic, we focused on current discourses about the effectiveness of different countermeasures. To this end, participants evaluated fictitious scientific data on the effectiveness of regulations to reduce CO2 emissions. In both studies, participants exhibited motivated reasoning as indicated by the observation that prior attitudes about CO2 reduction policies predicted evaluation of the scientific data. The degree of motivated reasoning was not related to individual difference variables, namely the ability to understand and reason with numbers (Numeracy), the willingness to show this ability (Need for Cognition), and the tendency to maximize one's individual utility (Dark Factor of Personality). However, numeracy was associated with a less biased interpretation of the presented information. Our research demonstrates that motivated reasoning is a general phenomenon, and points to numerical training as one way to improve reasoning.
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Dióxido de Carbono , Cambio Climático , Humanos , Cognición , Solución de Problemas , MotivaciónRESUMEN
Artificial intelligence (AI) has become an integral part of many contemporary technologies, such as social media platforms, smart devices, and global logistics systems. At the same time, research on the public acceptance of AI shows that many people feel quite apprehensive about the potential of such technologies-an observation that has been connected to both demographic and sociocultural user variables (e.g., age, previous media exposure). Yet, due to divergent and often ad-hoc measurements of AI-related attitudes, the current body of evidence remains inconclusive. Likewise, it is still unclear if attitudes towards AI are also affected by users' personality traits. In response to these research gaps, we offer a two-fold contribution. First, we present a novel, psychologically informed questionnaire (ATTARI-12) that captures attitudes towards AI as a single construct, independent of specific contexts or applications. Having observed good reliability and validity for our new measure across two studies (N1 = 490; N2 = 150), we examine several personality traits-the Big Five, the Dark Triad, and conspiracy mentality-as potential predictors of AI-related attitudes in a third study (N3 = 298). We find that agreeableness and younger age predict a more positive view towards artificially intelligent technology, whereas the susceptibility to conspiracy beliefs connects to a more negative attitude. Our findings are discussed considering potential limitations and future directions for research and practice.
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Inteligencia Artificial , Personalidad , Humanos , Reproducibilidad de los Resultados , Trastornos de la Personalidad , EmocionesRESUMEN
We present an analysis of high-resolution quasi-elastic neutron scattering spectra of phosphoglycerate kinase which elucidates the influence of the enzymatic activity on the dynamics of the protein. We show that in the active state the inter-domain motions are amplified and the intra-domain asymptotic power-law relaxation ât-α is accelerated, with a reduced coefficient α. Employing an energy landscape picture of protein dynamics, this observation can be translated into a widening of the distribution of energy barriers separating conformational substates of the protein.
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Difracción de Neutrones , Fosfoglicerato Quinasa , Proteínas , NeutronesRESUMEN
Reading is a popular leisure activity for children, teenagers, and adults. Several theories agree that reading might improve social cognition, but the empirical evidence remains tentative, with research on adolescents especially lacking. We employed a very large, and nationally representative, longitudinal dataset from the National Educational Panel Study (NEPS) in Germany to examine this hypothesis. Specifically, we tested whether reading prospectively predicted future self-reported prosocial behavior and social adjustment in adolescents, controlling for a number of covariates. Two-way cross-lagged panel analyses probed the longitudinal relationship between leisure reading and these social outcomes from Grade 6 to Grade 9. In addition, we examined the effect of cumulative reading experience across Grades 5-8 on future social outcomes, using structural equation modeling. We also explored the unique contributions of cumulative reading experience in different literary genres (classic literature, popular literature, nonfiction, comic books). Cumulative reading in general did not predict future prosocial behavior and social adjustment. However, cumulative reading of modern classic literature was positively associated with later prosocial behavior and social adjustment. PROTOCOL REGISTRATION: The stage 1 protocol for this Registered Report was accepted in principle on 08 November 2021. The protocol, as accepted by the journal, can be found at: https://doi.org/10.17605/OSF.IO/KSWY7 .
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Altruismo , Ajuste Social , Adulto , Niño , Humanos , Adolescente , Lectura , Actividades Recreativas , Alemania , Conducta Social , Estudios LongitudinalesRESUMEN
By depicting an unrealistic share of skinny or toned body types, modern mass media have been found to shift users' perception of an ideal body toward narrow and often unattainable standards. In response to this, the "#bodypositivity" (BoPo) movement on social media has set out to challenge restrictive body ideals, advocating for more open-minded views toward the human physique. Matching BoPo's emphasis on diversity, we hypothesized that viewing body-positive online content alters women's concept of an ideal body to encompass a broader range of body shapes (on a spectrum from skinny to obese). The results of two pre-registered experiments (N1 = 191; N2 = 266) support our assumption, connecting BoPo not only to a larger mean ideal body shape but also to a diversification of weight-related standards. We discuss our work as a crucial extension of prior research, noting that the range found in people's bodily ideals may be (at least) as relevant as their central tendency. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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The philosophical concept of informal fallacies-arguments that fail to provide sufficient support for a claim-is introduced and connected to the topic of fake news detection. We assumed that the ability to identify informal fallacies can be trained and that this ability enables individuals to better distinguish between fake news and real news. We tested these assumptions in a two-group between-participants experiment (N = 116). The two groups participated in a 30-minute-long text-based learning intervention: either about informal fallacies or about fake news. Learning about informal fallacies enhanced participants' ability to identify fallacious arguments one week later. Furthermore, the ability to identify fallacious arguments was associated with a better discernment between real news and fake news. Participants in the informal fallacy intervention group and the fake news intervention group performed equally well on the news discernment task. The contribution of (identifying) informal fallacies for research and practice is discussed.
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Desinformación , Aprendizaje , Humanos , Disentimientos y DisputasRESUMEN
A substantial number of people refused to get vaccinated against COVID-19, which prompts the question as to why. We focus on the role of individual worldviews about the nature and generation of knowledge (epistemic beliefs). We propose a model that includes epistemic beliefs, their relationship to the Dark Factor of Personality (D), and their mutual effect on the probability of having been vaccinated against COVID-19. Based on a US nationally representative sample (N = 1268), we show that stronger endorsement of post-truth epistemic beliefs was associated with a lower probability of having been vaccinated against COVID-19. D was also linked to a lower probability of having been vaccinated against COVID-19, which can be explained by post-truth epistemic beliefs. Our results indicate that the more individuals deliberately refrain from adhering to the better argument, the less likely they are vaccinated. More generally, post-truth epistemic beliefs pose a challenge for rational communication.
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Vacunas contra la COVID-19 , COVID-19 , Humanos , COVID-19/prevención & control , Trastornos de la Personalidad , Negativa a la Vacunación , Personalidad , VacunaciónRESUMEN
We report results from quasi-elastic neutron scattering studies on the rotational dynamics of formamidinium (HC[NH2]2+, FA) and methylammonium (CH3NH3+, MA) cations in FA1-xMAxPbI3 with x = 0 and 0.4 and compare it to the dynamics in MAPbI3. For FAPbI3, the FA cation dynamics evolve from nearly isotropic rotations in the high-temperature (T > 285 K) cubic phase through reorientations between preferred orientations in the intermediate-temperature tetragonal phase (140 K < T ⩽ 285 K) to an even more complex dynamics, due to a disordered arrangement of the FA cations, in the low-temperature tetragonal phase (T ⩽ 140 K). For FA0.6MA0.4PbI3, the dynamics of the respective organic cations evolve from a relatively similar behavior to FAPbI3 and MAPbI3 at room temperature to a different behavior in the lower-temperature phases where the MA cation dynamics are a factor of 50 faster as compared to those of MAPbI3. This insight suggests that tuning the MA/FA cation ratio may be a promising approach to tailoring the dynamics and, in effect, optical properties of FA1-xMAxPbI3.
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High-resolution inelastic neutron scattering has been used to study low-energy magnetic transitions in a Ho3+ complex. This complex crystallises in the high-symmetry space group P4/m and has near-perfect D4d symmetry, which has allowed for the determination of all relevant spin-Hamiltonian parameters. Static and dynamic inhomogeneity in the crystal lattice manifests as a temperature-dependent broadening of the observed magnetic excitations. By implementing distributions in the spin-Hamiltonian parameters, it is possible to reproduce with great accuracy the observed magnetic transition spectrum. This reveals the range to which extraneous perturbations of the crystal field affect low-energy electronic states, such as those involved in quantum tunnelling of magnetisation, in atomic clock transitions, or in spintronics.
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Neutron scattering offers the possibility to probe the dynamics within samples for a wide range of energies in a nondestructive manner and without labeling other than deuterium. In particular, neutron backscattering spectroscopy records the scattering signals at multiple scattering angles simultaneously and is well suited to study the dynamics of biological systems on the ps-ns timescale. By employing D2O-and possibly deuterated buffer components-the method allows monitoring of both center-of-mass diffusion and backbone and side-chain motions (internal dynamics) of proteins in liquid state. Additionally, hydration water dynamics can be studied by employing powders of perdeuterated proteins hydrated with H2O. This paper presents the workflow employed on the instrument IN16B at the Institut Laue-Langevin (ILL) to investigate protein and hydration water dynamics. The preparation of solution samples and hydrated protein powder samples using vapor exchange is explained. The data analysis procedure for both protein and hydration water dynamics is described for different types of datasets (quasielastic spectra or fixed-window scans) that can be obtained on a neutron backscattering spectrometer. The method is illustrated with two studies involving amyloid proteins. The aggregation of lysozyme into µm sized spherical aggregates-denoted particulates-is shown to occur in a one-step process on the space and time range probed on IN16B, while the internal dynamics remains unchanged. Further, the dynamics of hydration water of tau was studied on hydrated powders of perdeuterated protein. It is shown that translational motions of water are activated upon the formation of amyloid fibers. Finally, critical steps in the protocol are discussed as to how neutron scattering is positioned regarding the study of dynamics with respect to other experimental biophysical methods.
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Neutrones , Agua , Difracción de Neutrones/métodos , Polvos/química , Proteínas , Análisis Espectral , Agua/químicaRESUMEN
Semipermeable polymeric anion exchange membranes are essential for separation, filtration and energy conversion technologies including reverse electrodialysis systems that produce energy from salinity gradients, fuel cells to generate electrical power from the electrochemical reaction between hydrogen and oxygen, and water electrolyser systems that provide H2 fuel. Anion exchange membrane fuel cells and anion exchange membrane water electrolysers rely on the membrane to transport OH- ions between the cathode and anode in a process that involves cooperative interactions with H2O molecules and polymer dynamics. Understanding and controlling the interactions between the relaxation and diffusional processes pose a main scientific and critical membrane design challenge. Here quasi-elastic neutron scattering is applied over a wide range of timescales (100-103 ps) to disentangle the water, polymer relaxation and OH- diffusional dynamics in commercially available anion exchange membranes (Fumatech FAD-55) designed for selective anion transport across different technology platforms, using the concept of serial decoupling of relaxation and diffusional processes to analyse the data. Preliminary data are also reported for a laboratory-prepared anion exchange membrane especially designed for fuel cell applications.
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Polímeros , Agua , Aniones , Intercambio Iónico , Iones , Membranas Artificiales , Polímeros/química , Agua/químicaRESUMEN
OBJECTIVE: Global challenges such as climate change or the COVID-19 pandemic have drawn public attention to conspiracy theories and citizens' non-compliance to science-based behavioral guidelines. We focus on individuals' worldviews about how one can and should construct reality (epistemic beliefs) to explain the endorsement of conspiracy theories and behavior during the COVID-19 pandemic and propose the Dark Factor of Personality (D) as an antecedent of post-truth epistemic beliefs. METHOD AND RESULTS: This model is tested in four pre-registered studies. In Study 1 (N = 321), we found first evidence for a positive association between D and post-truth epistemic beliefs (Faith in Intuition for Facts, Need for Evidence, Truth is Political). In Study 2 (N = 453), we tested the model proper by further showing that post-truth epistemic beliefs predict the endorsement of COVID-19 conspiracies and disregarding COVID-19 behavioral guidelines. Study 3 (N = 923) largely replicated these results at a later stage of the pandemic. Finally, in Study 4 (N = 513), we replicated the results in a German sample, corroborating their cross-cultural validity. Interactions with political orientation were observed. CONCLUSION: Our research highlights that epistemic beliefs need to be taken into account when addressing major challenges to humankind.
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COVID-19 , Pandemias , Humanos , Personalidad , Trastornos de la Personalidad , IntuiciónRESUMEN
We report an analysis of high-resolution quasielastic neutron scattering spectra from Myelin Basic Protein (MBP) in solution, comparing the spectra at three different temperatures (283, 303, and 323 K) for a pure D2O buffer and a mixture of D2O buffer with 30% of deuterated trifluoroethanol (TFE). Accompanying experiments with dynamic light scattering and Circular Dichroism (CD) spectroscopy have been performed to obtain, respectively, the global diffusion constant and the secondary structure content of the molecule for both buffers as a function of temperature. Modeling the decay of the neutron intermediate scattering function by the Mittag-Leffler relaxation function, Ï(t) = Eα(-(t/τ)α) (0 < α < 1), we find that trifluoroethanol slows down the relaxation dynamics of the protein at 283 K and leads to a broader relaxation rate spectrum. This effect vanishes with increasing temperature, and at 323 K, its relaxation dynamics is identical in both solvents. These results are coherent with the data from dynamic light scattering, which show that the hydrodynamic radius of MBP in TFE-enriched solutions does not depend on temperature and is only slightly smaller compared to the pure D2O buffer, except for 283 K, where it is much reduced. In accordance with these observations, the CD spectra reveal that TFE induces essentially a partial transition from ß-strands to α-helices, but only a weak increase in the total secondary structure content, leaving about 50% of the protein unfolded. The results show that MBP is for all temperatures and in both buffers an intrinsically disordered protein and that TFE essentially induces a reduction in its hydrodynamic radius and its relaxation dynamics at low temperatures.
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Proteína Básica de Mielina , Difracción de Neutrones , Proteína Básica de Mielina/química , Proteína Básica de Mielina/metabolismo , Neutrones , Estructura Secundaria de Proteína , Soluciones , TrifluoroetanolRESUMEN
RATIONALE: High body mass and obesity are frequently linked to the use of sedentary media, like television (TV) or non-active video games. Empirical evidence regarding video gaming, however, has been mixed, and theoretical considerations explaining a relationship between general screen time and body mass may not generalize to non-active video gaming. OBJECTIVE: The current meta-analysis had two main goals. First, we wanted to provide an estimate of the average effect size of the relationship between sedentary video gaming and body mass. In doing so we acknowledged several context variables to gauge the stability of the average effect. Second, to provide additional evidence on processes, we tested the displacement effect of physical activity by video gaming time with the help of a meta-analytic structural equation model (MASEM). METHOD: Published and unpublished studies were identified through keyword searches in different databases and references in relevant reports were inspected for further studies. We present a random-effects, three-level meta-analysis based on 20 studies (total Nâ¯=â¯38,097) with 32 effect sizes. RESULTS: The analyses revealed a small positive relationship between non-active video game use and body mass, ρË=.09, 95% CI [0.03, 0.14], indicating that they shared less than 1% in variance. The studies showed significant heterogeneity, Q (31)â¯=â¯593.03, pâ¯<â¯.001, I2â¯=â¯95.13. Moderator analyses revealed that the relationship was more pronounced for adults, ρË=.22, 95% CI [0.04, 0.40], as compared to adolescents, ρË=.01, 95% CI [-0.21, 0.23], or children, ρË=.09, 95% CI [-0.07, 0.25]. Meta-analytic structural equation modeling found little evidence for a displacement of physical activity through time spent on video gaming. CONCLUSION: These results do not corroborate the assumption of a strong link between video gaming and body mass as respective associations are small and primarily observed among adults.
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Juegos de Video , Adolescente , Adulto , Niño , Ejercicio Físico , Humanos , Obesidad/epidemiología , Televisión , Juegos de Video/efectos adversosRESUMEN
The successful management of the COVID-19 pandemic depends on individuals accepting the current state of research and adhering to the preventive behaviors that follow from it. However, the processing of scientific results is not always rational, but influenced by prior attitudes as well as the ability to understand statistical data. Against this background, this study investigated the role of motivated reasoning and numeracy in the context of the current pandemic. To this end, participants (N = 417; US sample) evaluated two fictitious studies, one indicating that mask mandates in schools are an effective intervention to contain the spread of SARS-CoV-2, and one indicating that mask mandates in schools are counterproductive. Participants evaluated the studies in line with their prior attitude toward mask mandates. In addition, higher numeracy was associated with decreased bias, demonstrating that the ability to reason with numbers can lead to more accurate processing of statistical information.
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COVID-19 , Pandemias , Humanos , Pandemias/prevención & control , SARS-CoV-2 , Instituciones AcadémicasRESUMEN
Apolipoprotein B-100 (apo B-100) is the protein moiety of both low- and very-low-density lipoproteins, whose role is crucial to cholesterol and triglyceride transport. Aiming at the molecular dynamics' details of apo B-100, scarcely studied, we performed elastic and quasi-elastic incoherent neutron scattering (EINS, QENS) experiments combining different instruments and time scales. Similar to classical membrane proteins, the solubilization results in remaining detergent, here Nonidet P-40 (NP40). Therefore, we propose a framework for QENS studies of protein-detergent complexes, with the introduction of a combined model, including the experimental apo B-100/NP40 ratio. Relying on the simultaneous analysis of all QENS amplitudes, this approach is sensitive enough to separate both contributions. Its application identified two points: (i) apo B-100 slow dynamics and (ii) the acceleration of NP40 dynamics in the presence of apo B-100. Direct translation of the exposed methodology now makes the investigation of more membrane proteins by neutron spectroscopy achievable.
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Apolipoproteína B-100/química , Detergentes/química , Simulación de Dinámica Molecular , Humanos , Neutrones , Dispersión del Ángulo PequeñoRESUMEN
OBJECTIVES: Research has shown that cultural identity and psychological well-being are associated. We suggest that negative stereotypes challenge the psychological well-being of people with a migrant background. This research focused on the dynamics of adolescents' ethnic/racial identity (ERI), national identity, stereotype vulnerability, and psychological well-being on the individual level. The study was conducted in Austria over the course of one school year, providing insights on developmental implications of cultural identity for adolescents with a migrant background in Europe. METHODS: The sample consisted of 317 (T1) adolescents with a migrant background, recruited at Austrian high schools (age: M = 15.19, SD = 1.11; 233 female; ethnic background: mainly Turkey and Ex-Yugoslavian countries). Longitudinal data from a three-wave study were analyzed by means of a random-intercept cross-lagged panel model. RESULTS: Within-person effects provided a better explanation than the between-person approach. Within-person processes suggest that higher levels of ERI commitment and higher national identity predict higher levels of psychological well-being at a later time point, whereas higher levels of ERI exploration and higher stereotype vulnerability predict lower levels of psychological well-being. At the between-person level, findings indicate a positive correlation between ERI exploration and stereotype vulnerability. CONCLUSION: The cultural identity and psychological well-being of adolescents with a migrant background fluctuate over time, influenced by the social context. Stereotype vulnerability contributes to lower levels of psychological well-being among adolescents with a migrant background in Austria. Our findings highlight the necessity to partition the variance of constructs to avoid confounding of between-person and within-person effects. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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Identificación Social , Migrantes , Adolescente , Austria , Etnicidad , Femenino , Humanos , Estudios LongitudinalesRESUMEN
Humanoid robots (i.e., robots with a human-like body) are projected to be mass marketed in the future in several fields of application. Today, however, user evaluations of humanoid robots are often based on mediated depictions rather than actual observations or interactions with a robot, which holds true not least for scientific user studies. People can be confronted with robots in various modes of presentation, among them (1) 2D videos, (2) 3D, i.e., stereoscopic videos, (3) immersive Virtual Reality (VR), or (4) live on site. A systematic investigation into how such differential modes of presentation influence user perceptions of a robot is still lacking. Thus, the current study systematically compares the effects of different presentation modes with varying immersive potential on user evaluations of a humanoid service robot. Participants (N = 120) observed an interaction between a humanoid service robot and an actor either on 2D or 3D video, via a virtual reality headset (VR) or live. We found support for the expected effect of the presentation mode on perceived immediacy. Effects regarding the degree of human likeness that was attributed to the robot were mixed. The presentation mode had no influence on evaluations in terms of eeriness, likability, and purchase intentions. Implications for empirical research on humanoid robots and practice are discussed.
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We have investigated the dynamics of liquid water confined in mesostructured porous silica (MCM-41) and periodic mesoporous organosilicas (PMOs) by incoherent quasielastic neutron scattering experiments. The effect of tuning the water/surface interaction from hydrophilic to more hydrophobic on the water mobility, while keeping the pore size in the range 3.5 nm-4.1 nm, was assessed from the comparative study of three PMOs comprising different organic bridging units and the purely siliceous MCM-41 case. An extended dynamical range was achieved by combining time-of-flight (IN5B) and backscattering (IN16B) quasielastic neutron spectrometers providing complementary energy resolutions. Liquid water was studied at regularly spaced temperatures ranging from 300 K to 243 K. In all systems, the molecular dynamics could be described consistently by the combination of two independent motions resulting from fast local motion around the average molecule position and the confined translational jump diffusion of its center of mass. All the molecules performed local relaxations, whereas the translational motion of a fraction of molecules was frozen on the experimental timescale. This study provides a comprehensive microscopic view on the dynamics of liquid water confined in mesopores, with distinct surface chemistries, in terms of non-mobile/mobile fraction, self-diffusion coefficient, residence time, confining radius, local relaxation time, and their temperature dependence. Importantly, it demonstrates that the strength of the water/surface interaction determines the long-time tail of the dynamics, which we attributed to the translational diffusion of interfacial molecules, while the water dynamics in the pore center is barely affected by the interface hydrophilicity.