The accuracy of some density functional (DF) models widely used in material science depends on empirical or free parameters that are commonly tuned using reference physical properties. Grid-search ...methods are the standard numerical approximations used to find the optimal values of the free parameters, making the computational complexity to scale with the number of points in the grid. In this report, we illustrate that Bayesian optimization (BO), a sample-efficient machine learning algorithm, can calibrate different density functional models, e.g., hybrid exchange-correlation and range-separated density functionals. Using the atomization energies and bond lengths from the Gaussian-1 (G1) and Gaussian-2 (G2) databases, we show that BO optimizes the free parameters of the hybrid exchange-correlation functionals with approximately 55 evaluations of the error function. We also show that selecting exchange-correlation functionals for different physical systems can be done with BO. We jointly optimize and select the form of the exchange-correlation functionals and the free parameters by minimizing the root-mean-square error functions for the G1 and G2 data set atomization energies. The calibrated DF model is more accurate on average than standard DF methods, e.g., PBE0 and B3LYP.
The mathematical representation of large data sets of electronic energies has seen substantial progress in the past 10 years. The so-called Permutationally Invariant Polynomial (PIP) representation ...is one established approach. This approach dates from 2003, when a global potential energy surface (PES) for CH5 + was reported using a basis of polynomials that are invariant with respect to the 120 permutations of the five equivalent H atoms. More recently, several approaches from “machine learning” have been applied to fit these large data sets. Gaussian Process (GP) regression is such an approach. Here, we consider the implementation of the (full) GP due to Krems and co-workers, with a modification that renders it permutationally invariant, which we denote by PIP-GP. This modification uses the approach of Guo and co-workers and later extended by Zhang and co-workers, to achieve permutational invariance for neural-network fits. The PIP, GP, and PIP-GP approaches are applied to four case studies for fitting data sets of electronic energies: H3O+, OCHCO+, and H2CO/cis-HCOH/trans-HCOH with the goal of assessing precision, accuracy in normal-mode analysis and barrier heights, and timings. We also report an application to (HCOOH)2, where the full PIP approach is possible but where the PIP-GP one is not feasible. However, by replicating data, which is feasible in this case, the GP approach is able to represent the data with precision comparable to that of the PIP approach. We examine these assessments for varying sizes of data sets in each case to determine the dependence of properties of the fits on the training data size. We conclude with some comments on the different aspects of computational effort of the PIP, GP, and PIP-GP approaches and also challenges these methods face for more “rugged” PESs, exemplified here by H2CO/cis-HCOH/trans-HCOH.
Plant peroxisomes have the capacity to generate different reactive oxygen and nitrogen species (ROS and RNS), such as H2O2, superoxide radical (O2· −), nitric oxide and peroxynitrite (ONOO‐). These ...organelles have an active nitro‐oxidative metabolism which can be exacerbated by adverse stress conditions. Hydrogen sulfide (H2S) is a new signaling gasotransmitter which can mediate the posttranslational modification (PTM) persulfidation. We used Arabidopsis thaliana transgenic seedlings expressing cyan fluorescent protein (CFP) fused to a canonical peroxisome targeting signal 1 (PTS1) to visualize peroxisomes in living cells, as well as a specific fluorescent probe which showed that peroxisomes contain H2S. H2S was also detected in chloroplasts under glyphosate‐induced oxidative stress conditions. Peroxisomal enzyme activities, including catalase, photorespiratory H2O2‐generating glycolate oxidase (GOX) and hydroxypyruvate reductase (HPR), were assayed in vitro with a H2S donor. In line with the persulfidation of this enzyme, catalase activity declined significantly in the presence of the H2S donor. To corroborate the inhibitory effect of H2S on catalase activity, we also assayed pure catalase from bovine liver and pepper fruit‐enriched samples, in which catalase activity was inhibited. Taken together, these data provide evidence of the presence of H2S in plant peroxisomes which appears to regulate catalase activity and, consequently, the peroxisomal H2O2 metabolism.
Plant peroxisomes are subcellular compartments with an active metabolism of reactive oxygen and nitrogen species (ROS and RNS). However, new molecules seem to be present in this organelle. Here, we present biochemical and cell biology evidences of the presence of hydrogen sulfi de (H2S) in peroxisomes which regulates catalase activity.
We analyze orbital solutions for 48 massive multiple-star systems in the Cygnus OB2 association, 23 of which are newly presented here, to find that the observed distribution of orbital periods is ...approximately uniform in log P for P < 45 days, but it is not scale-free. We identify six stars, all supergiants, that exhibit aperiodic velocity variations of ~30 km ssup -1 attributed to atmospheric fluctuations.
IntroductionAttempts at suicide and suicidal tendencies have been the most frequent and common reasons for adolescent inpatient treatments since the last Covid-19 pandemic. Indeed, the WHO has ...reported that the second most frequent cause of mortality in adolescents is related to suicidal acts.ObjectivesThe Sun Project, which is a pilot research program aimed at finding a comprehensive set of steps for treatment, has been developed at the Versailles Medical Center in France and provides multidisciplinary tools to tackle this phenomenon.MethodsThis retrospective observational research with a cohort of fifty people between pre-teen and adolescence has taken advantage of different elements of specific psychotherapeutical approaches such as Acceptance and Commitment Therapy, Interpersonal Psychotherapy, Compassion, Narrative, Dialectical and Cognitive Behavioural Therapies in relation to Family-Based Therapy and employs elements of Emotional Freedom Techniques as well as the CESAR program (Cognitive, Emotional and psycho-Social Avatar Reinforcement program).ResultsThe results have been very positive and this is attributed to the transdisciplinary network around each patient, family inclusion and the multi-pronged psychotherapeutic approach based on functional analysis of every patient’s situation.ConclusionsIn short, The Sun Project has shown that these approaches and interventions give excellent and rapid outcomes in pre-teens and adolescents suffering from suicide related thoughts and acts.Disclosure of InterestNone Declared
Introduction
Drawing represents mainly a motor activity of expression. Drawing represents a form of non-verbal language that is very important both cognitively and affectively. Therefore, it allows ...to hypothesise and evaluate the degree of neurodevelopment of individuals as well as their level of interaction with the environment.
Family sketches can be evaluated in a projective, neurocognitive and affective way to provide insights on the attachment system, degree of bonding, communication, social and affect interaction as well as difficulties or problems that have motivated emergency consultation.
Objectives
This study evaluate the possible correlation between family dysfunction and irritability as cause of request of consultation in an emergency department of mental health in child & adolescents through the analysis of family drawings.
Methods
This is a retrospective, observational study of correlation between the reasons of emergency consultations, dysfunctional irritability and family difficulties represented through family drawing. It is based on a randomised sample of 30 reports of emergency appointments of children between 8 to 13 years old that have been examined in the Child & Adolescent Psychiatry Emergency Department at the Pitié Salpêtrière Hospital during two years for Emotional or Irritability dysfunction.
An adaptation of both Goodenough-Harris Drawing projective test and Corman test were used to evaluate findings from family drawings as well as neurocognitive parameters of drawing technics, sociodemographic dates, cognitive level and family dysfunction.
Results
The degree of cohesion, identification and devaluation of adult figures have been important elements of interpretation in irritability dysfunction and family drawings.
Conclusions
The family environment could be a factor in the interpretation of chronic irritability and its manifestations on the child’s family drawings establish a clear correlation.
The adapted assessment of the family drawing could be an important tool in the nosological exploration of children’s mental health in emergency, especially on relational systemic representation and symbolization.
Disclosure of Interest
None Declared
Functionalized indoles are recurrent motifs in bioactive natural products and pharmaceuticals. While transition metal‐catalyzed carbene transfer has provided an attractive route to afford ...C3‐functionalized indoles, these protocols are viable only in the presence of N‐protected indoles, owing to competition from the more facile N−H insertion reaction. Herein, a biocatalytic strategy for enabling the direct C−H functionalization of unprotected indoles is reported. Engineered variants of myoglobin provide efficient biocatalysts for this reaction, which has no precedents in the biological world, enabling the transformation of a broad range of indoles in the presence of ethyl α‐diazoacetate to give the corresponding C3‐functionalized derivatives in high conversion yields and excellent chemoselectivity. This strategy could be exploited to develop a concise chemoenzymatic route to afford the nonsteroidal anti‐inflammatory drug indomethacin.
Catalysis without protection: A biocatalytic strategy for the synthesis of C3‐functionalized indoles via myoglobin‐catalyzed carbene transfer is reported. This approach enabled the transformation of a broad range of indole derivatives bearing unprotected N−H groups with high efficiency and excellent chemoselectivity. This transformation could be integrated into a chemoenzymatic scheme for the synthesis of a drug molecule (indomethacin) at the preparative scale.
Currently, air pollution is a critical public health problem, which means that the daily measurement of urban air quality can be enriched if measured in a personalized way. Personal environmental ...monitoring devices can guide the population to take action. They can track their daily activities, avoiding situations that could affect their health, allowing them to precisely know the air quality they breathe in real-time in various microenvironments. In this work, we present a review of cyclonic separation technology patents, such as pre-separators in monitoring devices. We focused on the state-of-the-art commercially available personal monitoring devices, the classification of kinds of patents, and a review of cyclone patents and gas–particle separation behaviors. The World Intellectual Property Organization IP’s portal and Google Patents search engine were used, using international patent classification plus mesh terms involving a cyclone in an air particulate monitor after predefining inclusion and exclusion criteria such as gas–air cyclones, high efficiency, and fine particle separation. Twenty-nine patents were analyzed according to the main characteristics (e.g., cut point, flow rate, and cyclone improvement) available in the patent document. The wide range of cyclones indicates a maximum flow rate of between 0.5 and 4.5 Lpm and a lower cyclone cut point of 0.8 μm. This review includes a discussion of the most relevant features of the patent documents (flow rate, particle cut point, some cyclone improvements, and technology detection). This paper aims to give an overview of the use of cyclones as pre-separators for personal air monitoring devices and to acknowledge the patented improvements of new inventors or developers.
Alloying noble metals with non-noble metals enables high activity while reducing the cost of electrocatalysts in fuel cells. However, under fuel cell operating conditions, state-of-the-art oxygen ...reduction reaction alloy catalysts either feature high atomic percentages of noble metals (>70%) with limited durability or show poor durability when lower percentages of noble metals (<50%) are used. Here, we demonstrate a highly-durable alloy catalyst derived by alloying PtPd (<50%) with 3d-transition metals (Cu, Ni or Co) in ternary compositions. The origin of the high durability is probed by in-situ/operando high-energy synchrotron X-ray diffraction coupled with pair distribution function analysis of atomic phase structures and strains, revealing an important role of realloying in the compressively-strained single-phase alloy state despite the occurrence of dealloying. The implication of the finding, a striking departure from previous perceptions of phase-segregated noble metal skin or complete dealloying of non-noble metals, is the fulfilling of the promise of alloy catalysts for mass commercialization of fuel cells.
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