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Teaching laboratories are designed to educate students on basic theories and techniques through guided laboratory experiments. As advances in automation revolutionize research chemistry laboratories, teaching tools can advance to reflect these changes. In this study, we integrated several programmable instruments, including automated pumps for liquid transfer, into an augmented titration setup that can be operated remotely. Our setup empowers students to learn the conceptual, technical, and practical aspects of titration by leveraging laboratory automation tools. Our system uses Siri as a speech recognition tool and the Python programming language to develop action routines for titration uses. The application of Siri provides a smooth user-to-instrument experience, and the use of Python allows coders to effectively develop and maintain the workflow. Three chemistry professors were invited to participate in usability tests of the system using a mobile device. Their positive feedback highlights the promise of our system as a valuable addition to undergraduate chemistry teaching laboratories. This titration setup addresses accessibility challenges and distance learning requirements for chemical education. Further, our tool introduces students to the type of automated experimentation that is emerging as the modern standard in chemistry research laboratories.

[Abridged] Context: We present a systematic X-ray spectral-timing study of the recently discovered, exceptionally bright black hole X-ray binary system MAXI J1820+070. Our analysis focuses on the first part of the 2018 outburst, covering the rise throughout the hard state, the bright hard and hard-intermediate states, and the transition to the soft-intermediate state. Aims: We address the issue of constraining the geometry of the innermost accretion flow and its evolution throughout an outburst. Methods: We employed two independent X-ray spectral-timing methods applied to the NICER data of MAXI J1820+070. We first identified and tracked the evolution of a characteristic frequency of soft X-ray reverberation lags. Then, we studied the spectral evolution of the quasi-thermal component responsible for the observed thermal reverberation lags. Results: The frequency of thermal reverberation lags steadily increases throughout most of the outburst, implying that the relative distance between the X-ray source and the disc decreases as the source softens. However, near transition this evolution breaks, showing a sudden increase (decrease) of lag amplitude (frequency). The temperature of the quasi-thermal component in covariance spectra consistently increases throughout all the analysed observations. Conclusions: The behaviour of thermal reverberation lags near transition might be related to the relativistic plasma ejections detected at radio wavelengths, suggesting a causal connection between the two phenomena. Throughout most of the hard and hard-intermediate states the disc is consistent with being truncated (with an inner radius $R_{\rm in}>\sim 10 R_{\rm g}$), reaching close to the innermost stable circular orbit only near transition., Accepted for publication in Astronomy & Astrophysics, matches published version

Chemists spend an inordinate amount of time performing low-level tasks based on visual observation. Camera-enabled laboratory equipment in conversation with computer vision algorithms can be used to automate many of these processes, thereby freeing up valuable time and resources. We developed a generalizable computer-vision based system capable of monitoring and controlling liquid-level across a variety of chemistry applications. This paper reports on the system’s motivation, architecture, and successful deployment in three experimental use cases which require continous stirring: continuous preferential crystallization (CPC), slurry filtration, and solvent swap distillation

An autonomous laboratory for thin film discovery is used to optimize the doping and annealing of organic semiconductors., Discovering and optimizing commercially viable materials for clean energy applications typically takes more than a decade. Self-driving laboratories that iteratively design, execute, and learn from materials science experiments in a fully autonomous loop present an opportunity to accelerate this research process. We report here a modular robotic platform driven by a model-based optimization algorithm capable of autonomously optimizing the optical and electronic properties of thin-film materials by modifying the film composition and processing conditions. We demonstrate the power of this platform by using it to maximize the hole mobility of organic hole transport materials commonly used in perovskite solar cells and consumer electronics. This demonstration highlights the possibilities of using autonomous laboratories to discover organic and inorganic materials relevant to materials sciences and clean energy technologies.

AIM To explore the prevalence of Aberrant Salience (AS, an alleged experiential feature of psychosis-proneness) in Italian young people and corroborate the transcultural validity of the Aberrant Salience Inventory (ASI). METHODS Young adults attending an Italian university (n = 649) underwent serial evaluations with the ASI together with psychometric proxies for help seeking General Health Questionnaire and attenuated positive and negative symptoms Schizotypal Personality Questionnaire (SPQ). The distribution of ASI scores was explored with latent class analysis (LCA). RESULTS Reliability of the Italian version of the ASI (I-ASI) was acceptable for all subscales (ordinal alpha >.70). Concurrent validity was in the expected direction, with higher correlations with measures of attenuated positive symptoms vs negative symptoms of psychosis (Steigers' z test, P < .005 in all comparisons). LCA identified three classes, with 217 (33.4%) participants in the "high aberrant salience" class. Gender and age were not related to class membership. Compared to the baseline class, SPQ scores in the schizotypy range were more likely in the "high aberrant salience" class (OR = 39.1; 95%confidence interval: 5.30-288.1). CONCLUSION AS is a relatively common experience among Italian young people. The study also confirmed the validity of field-testing ASI as a tool for the real-world characterization of people with vulnerability to psychosis, such as symptomatic help seekers with clinical high-risk states.

Aims. We analyzed multi-epoch X-ray data of the Ultraluminous X-ray source (ULX) NGC 5055 X-1, with luminosity up to $2.32\times10^{40}\ \rm erg\ s^{-1}$, in order to constrain the physical parameters of the source. Methods. We performed timing and spectral analysis of Chandra and XMM-Newton observations. We used spectral models which assume the emission is from an accreting black hole system. We fit the data with a multicolor disk (MCD) combined with a powerlaw (PL) or a thermal Comptonization (NTHCOMP) component, and compared those fits with a slim disk model. Results. The lightcurves of the source do not show significant variability. From the hardness ratios (3-10 keV/0.3-3 keV flux) we infer that the source is not spectrally variable. We found that the photon index is tightly, positively correlated with the unabsorbed 0.3-10 keV flux and the hydrogen column density. Furthermore, the temperature emissivity profile indicates a deviation from the standard sub-Eddington thin disk model. The source shows an inverse correlation between luminosity and inner disk temperature in all fitted models. Conclusions. Our analysis favors the source to be in an ultraluminous soft state. The positive correlations between the photon index and the flux, and between the photon index and the hydrogen column density may suggest the source is accreting at high Eddington ratios and might indicate the presence of a wind. The inverse luminosity relation with the inner disk temperature for all spectral models may indicate that the emission is geometrically beamed by an optically thick outflow., Comment: 8 pages, 10 figures, Accepted for publication in A&A

Sparse evidence of a co-aggregation of the risk of schizophrenia and bipolar disorder provides support for a shared but nonspecific genetic etiology of bipolar disorder and schizophrenia. Temperaments are conceptualized as trait sub-syndromic conditions of major pathologies. This study set out to test the hypothesis of a continuum between schizotypy and affective temperaments versus the alternative hypothesis of their independence based on a cross-sectional, survey design involving 649 (males: 47%) college students. The short 39-item TEMPS-A and the SPQ were used as measures of the affective temperaments and of schizotypy, respectively. Confirmatory factor analyses were applied to a unidimensional model, to a standard correlate traits model, to second-order representations of a common latent structure, and to a bifactor model. Confirmatory bifactor modeling provided evidence against a complete independence of the dimensions subsumed by the affective and the schizotypal traits. The best solution distinguished between two sub-domains grouping positive symptoms and negative symptoms as measured by the SPQ subscales, and a sub-domain related to the affective temperaments as measured by the TEMPS-A. Limitations due to the use of subscales from two different tools should be taken into account.

Background The Temperament Evaluation of Memphis, Pisa, Paris and San Diego – Autoquestionnaire (TEMPS-A) is a widely used self-reported tool aimed at measuring the affective temperaments that define the bipolar spectrum, with cyclothymic, depressive, irritable, hyperthymic, and anxious subscales. Confirmatory factor analysis (CFA) was rarely used to confirm the expected five-factor model. Measurement invariance was never tested. Methods Cross-sectional, survey design involving 649 Italian college students (males: 47%). The short 39-item TEMPS-A and the 12-item General Health Questionnaire (GHQ-12) were used as measures of the affective temperaments and of psychological distress, respectively. CFA was applied to the TEMPS-A. Measurement invariance by gender, age and levels of psychological distress on the GHQ-12 was calculated with the establishment of subsequent equivalence constraints in the model parameters across groups. Results The expected five-factor model had the best fit for all CFA indexes. Configural, metric and scalar invariance of the five-factor model of the TEMPS-A was proved across gender, age and levels of psychological distress of the participants. The hyperthymic temperament subscale has low or no links with the other affective temperament subscales, which were interrelated with medium to large effect sizes. Limitations College students might be not representative of the general population. No information on the clinical status of the students was available beyond self-report data. Conclusion The study proved the measurement invariance of the (short) TEMPS-A, which is a pre-requisite to compare groups or individuals in cross-sectional and longitudinal surveys. Generalizability cannot be assumed without replication of the findings in clinical samples.