bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical Investigation of Optical and Nonlinear Optical (NLO) Properties of 3‐Azabenzanthrone Analogues : DFT and TD‐DFT Approach.
Authors: Lokhande Prerana K M. , Patil Dinesh S. , Kadam Mayuri M , Sekar Nagaiyan 
Published: September 2019

Abstract3‐Azabenzanthrone based chromophores are investigated to study the effect of different substituents on optical and “non‐linear optical (NLO)” properties by means of density functional theory (DFT) with global hybrid functionals (GHs) ‐ B3LYP and BHandHLYP, range separated hybrid functionals (RSHs) CAM−B3LYP, wB97, wB97X, wB97XD and the basis sets 6–31+G(d), cc‐pVDZ, and cc‐pVTZ. It is observed that the incorporation of an electron withdrawing group at the 1 position and an electron donating group at the 2 and 6 positions of 3‐azabenzanthrone system led to more red shifted absorption maxima and showed better NLO response. Molecule 3 with electron withdrawing ‐CN at the 1 position exhibited the highest absorption wavelength (λ= 590 nm). The geometries, dipole moments, HOMO‐LUMO energy gaps, total hyperpolarizability are calculated to investigate the effect of different substituents on the photophysical and NLO properties of 3‐azabenzanthrone based chromophores. The insertion of ‐CN group at the 1 position of 3‐azabenzanthrone system resulted in higher first order hyperpolarizability (β0). The β0 values of 3, 5, 6 and 12 are found to be the maximum among other remaining molecules as the “Bond Length Alternation (BLA)” and “Bond Order Alternation (BOA)” parameters tend to zero. The charge transfer (CT) properties of these analogues are established using molecular electrostatic potential (MEP) analysis and quinoidal character at the same level of theory.
Unravelling the Weak Interactions in Binary Clusters of Serotonin and Amino Acid Residues
Authors: Yang Mengzhou , Huang Dajiang , Wu Haiming , Zhang Hanyu , An Pan , Yuan Chengqian , Su Peifeng , Luo Zhixun 
Published: September 2019

AbstractAs a monoamine neurotransmitter, serotonin affects a wide range of physiological and behavioral procedures of humans but its biological function is complex and multifaceted. Here we present a comprehensive study of the weak serotonin‐residue interactions from cluster science point of view. Eight pairs of serotonin‐residue binary clusters are representatively studied. Upon the most stable structures we depict the hydrogen bonding interaction patterns, along with natural bond orbital (NBO) analysis, atoms in molecules (AIM) analysis, generalized Kohn‐Sham energy decomposition analysis (GKS‐EDA), as well as noncovalent interaction plots based on independent gradient model (IGM). It is found that, for nitrogenous residues, the N⋅⋅⋅H−O dominates the noncovalent interactions; while for hydroxyl‐containing residues, O−H⋅⋅⋅N takes over the dominant interactions; for oxygen and nitrogen‐free residues, both electrostatic and VDW‐like H‐bonds stabilize the binary clusters. This information enriches the molecular mechanism of serotonin receptors and paves a way to study the weak interactions of physiological‐active molecules and also supramolecular materials.
Synthesis of Nano‐Hierarchical Ferrierite with Sole Template and Its Catalytic Application in n‐Butene Skeletal Isomerization
Authors: Liu Wen , Hu Haiqiang , Ke Ming , Liu Yang , Zhang Lei , Xia Chengjie , Wang Qi 
Published: September 2019

AbstractNano‐hierarchical ferrierite(FER) was successfully synthesized by using pyrrolidine as sole organic structure directing(OSDA) agent under static hydrothermal conditions.SEM images showed that the morphology of the product was a loose three‐stage accumulation structure by nano‐rod crystal grains .The influence of crystallization temperature, gel alkalinity, crystallization time and the amount of OSDA on synthesis of FER was investigated in detail.Moreover,FER catalytic performance in n‐butene skeletal isomerizatio was investigated.The results showed that, compared with the commercial FER, the nano‐hierarchical FER showed better catalytic activity.
Mechanical properties of mixed steel fiber reinforced concrete with the combination of micro and macro steel fibers
Authors: Dhanapal Jegatheeswaran , Jeyaprakash Sridhar 
Published: September 2019

AbstractThe paper intends to analyze and study the features of steel fiber reinforced concrete (SFRC) and plain concrete that contains combined fibers of various aspect ratios. Experiments on works are held to examine the features of the new combination of concretes. Simultaneously, the characteristics of the concretes that are hardened are examined by performing tests on compressions, flexural strength tests, and split tensile strength (STS). It further verifies the effects of fibers when they are distributed in the hinged zone of structural components to obtain financial benefits by minimizing the ingredients in steel fiber in the concrete mix. The result shows that the combined reinforced concrete steel fiber can be employed as the better combination to be applied in SFRC for achieving strength in STS, and flexure. Anyhow, enhanced ability for working was achieved as more amounts of microfibers in mixed with concrete. And there is slight variation in the features of concrete between beam of fibers with full length and fibers which are available in hinged zone. Similarly, the categorization of neural network such as Neural Network–Levenberg–Marquardt (NN‐LM) and Neural Network‐Gradient Descent (NN‐GD) is further used to perform the experimentation in an intelligent manner, which comes close to the actual values while calculating the mean absolute error (MAE) and root mean square error (RMSE) values.
The nomenclature and application of the names Euphorbia candelabrum Welw. and Euphorbia ingens in tropical Africa
Authors: Bruyns Peter V. , Berry Paul E. 
Published: September 2019

AbstractDuring the last 40 years, one of the most widespread and conspicuous succulent trees in East and north‐east Africa has been referred to as Euphorbia candelabrum Kotschy or as E. candelabrum Trémaux ex Kotschy. This name is a later homonym of E. candelabrum Welw., and consequently it is illegitimate. The species to which the name E. candelabrum Kotschy has been widely applied is shown to be conspecific with E. ingens, which occurs from southern Ethiopia to subtropical South Africa.
The Chronus Quantum software package
Authors: Williams‐Young David B. , Petrone Alessio , Sun Shichao , Stetina Torin F. , Lestrange Patrick , Hoyer Chad E. , Nascimento Daniel R. , Koulias Lauren , Wildman Andrew , Kasper Joseph , Goings Joshua J. , Ding Feizhi , DePrince A. Eugene , Valeev Edward F. , Li Xiaosong 
Published: September 2019

AbstractThe Chronus Quantum (ChronusQ) software package is an open source (under the GNU General Public License v2) software infrastructure which targets the solution of challenging problems that arise in ab initio electronic structure theory. Special emphasis is placed on the consistent treatment of time dependence and spin in the electronic wave function, as well as the inclusion of relativistic effects in said treatments. In addition, ChronusQ provides support for the inclusion of uniform finite magnetic fields as external perturbations through the use of gauge‐including atomic orbitals. ChronusQ is a parallel electronic structure code written in modern C++ which utilizes both message passing implementation and shared memory (OpenMP) parallelism. In addition to the examination of the current state of code base itself, a discussion regarding ongoing developments and developer contributions will also be provided.This article is categorized under:
Software > Quantum Chemistry
Electronic Structure Theory > Ab Initio Electronic Structure Methods
Electronic Structure Theory > Density Functional Theory
Enacting a National Reform Interval in Times of Uncertainty: Evaluation Gluttony Among the Willing
Authors: Lindgren Joakim , Rönnberg Linda , Hult Agneta , Segerholm Christina 
Published: September 2019

AbstractThis chapter offers an empirical illustration of the governing-evaluation-knowledge nexus by pinpointing a particular situation, a pause between two national evaluation and quality assurance (EQA) reforms, while a new national system was being planned and prepared, but its final design was not yet decided upon. This situation – unusual in the Swedish higher education policy context – adds uncertainty to the situation and opens a potential space for policymakers and higher education institutions (HEIs) to navigate. We draw on interviews and documents collected from four HEIs during this reform interval. We analyse and discuss how the four institutions navigate, coordinate, mobilise, copy, and learn in a situation without a formal national EQA system in place but in which the wider higher education policy context is deeply infused with contemporary trends and international policies and ideas on quality assurance (QA). We found that context and institutional preconditions set their mark on the work undertaken during this interval. We also discerned tendencies of homogenisation and isomorphism. Finally, we highlight the tendency of further expansion of EQA activities.
Relaunching National Evaluation and Quality Assurance: Governing by Piloting
Authors: Lindgren Joakim , Rönnberg Linda , Hult Agneta , Segerholm Christina 
Published: September 2019

AbstractThis chapter seeks to explore and discuss enactments in the process of piloting a part of the 2016 national evaluation and quality assurance system, namely, the pilot of institutional reviews in which higher education institutions’ internal quality assurance systems were evaluated by the Swedish Higher Education Authority. The chapter analyses the work and experiences of the different actors that took part in these processes. It shows that the pilot includes extensive work that links people, places, policies, practices, and power in particular ways and that numerous translations are made at different stages and by different actors. The results highlight the amount and forms of work done in these processes in general and in particular by actors who we have labelled “qualocrats”. Their embodied form of expertise is mobilised as they move between and across different domains to enact and promote certain knowledge in and of evaluation and quality assurance. The chapter finally suggests that the deliberate temporal design as a pilot study opened up for mutual adjustments, learning, and dialogue but also gave rise to contradictory anticipatory governing signals.
Neural Network Guided Tree-Search Policies for Synthesis Planning
Authors: Thakkar Amol , Bjerrum Esben Jannik , Engkvist Ola , Reymond Jean-Louis 
Published: September 2019

AbstractDevelopments and accessibility of computational methods within machine learning and deep learning have led to the resurgence of methods for computer assisted synthesis planning (CASP). In this paper we introduce our viewpoints on the analysis of reaction data, model building and evaluation. We show how the models’ performance is affected by the specificity of the extracted reaction rules (templates) and outline the direction of research within our group.
Progressive Docking - Deep Learning Based Approach for Accelerated Virtual Screening
Authors: Agrawal Vibudh , Gentile Francesco , Hsing Michael , Ban Fuqiang , Cherkasov Artem 
Published: September 2019

AbstractWe have developed a novel, hybrid QSAR-docking approach (called ‘progressive docking’) that can speed up the process of virtual screening by enhancing it with Deep Learning models trained on-the-go on produced docking scores. The developed method can, therefore, predict docking outcome for yet unprocessed molecular entries and hence to progressively remove unfavorable chemical structures from the remaining docking base. This approach provides 50–100X speed increase for the standard docking procedures while retaining >90% of qualified molecules. We demonstrate that the use of PD allows processing of about 360 million molecules just in 2 weeks using a standard 200 CPU setup.
Attention and Edge Memory Convolution for Bioactivity Prediction
Authors: Withnall Michael , Lindelöf Edvard , Engkvist Ola , Chen Hongming 
Published: September 2019

AbstractWe present some augmentations to literature Message Passing Neural Network (MPNN) architectures and benchmark their performances against a wide range of chemically and pharmaceutically relevant datasets. We analyse the effects of activation function for regularisation, we propose a new graph attention mechanism, and we implement a new edge-based memory system that should maximise the effectiveness of hidden state usage by directing and isolating information flow around the graph. We compare our results to the MolNet [14] benchmarking paper results on graph-based techniques, and also investigate the effect of method performance as a function of dataset preprocessing.
Using an Autoencoder for Dimensionality Reduction in Quantum Dynamics
Authors: Reiter Sebastian , Schnappinger Thomas , de Vivie-Riedle Regina 
Published: September 2019

AbstractA key step in performing quantum dynamics for a chemical system is the reduction of dimensionality to allow a numerical treatment. Here, we introduce a machine learning approach for the (semi)automatic construction of reactive coordinates. After generating a meaningful data set from trajectory calculations, we train an autoencoder to find a low-dimensional set of non-linear coordinates for use in molecular quantum dynamics. We compare the wave packet dynamics of proton transfer reactions in both linear and non-linear coordinate spaces and find significant improvement for physical properties like reaction timescales.
Prediction of the Atomization Energy of Molecules Using Coulomb Matrix and Atomic Composition in a Bayesian Regularized Neural Networks
Authors: Tchagang Alain B. , Valdés Julio J. 
Published: September 2019

AbstractExact calculation of electronic properties of molecules is a fundamental step for intelligent and rational compounds and materials design. The intrinsically graph-like and non-vectorial nature of molecular data generates a unique and challenging machine learning problem. In this paper we embrace a learning from scratch approach where the quantum mechanical electronic properties of molecules are predicted directly from the raw molecular geometry, similar to some recent works. But, unlike these previous endeavors, our study suggests a benefit from combining molecular geometry embedded in the Coulomb matrix with the atomic composition of molecules. Using the new combined features in a Bayesian regularized neural networks, our results improve well-known results from the literature on the QM7 dataset from a mean absolute error of 3.51 kcal/mol down to 3.0 kcal/mol.
Augmentation Is What You Need!
Authors: Tetko Igor V. , Karpov Pavel , Bruno Eric , Kimber Talia B. , Godin Guillaume 
Published: September 2019

AbstractWe investigate the effect of augmentation of SMILES to increase the performance of convolutional neural network models by extending the results of our previous study [1] to new methods and augmentation scenarios. We demonstrate that augmentation significantly increases performance and this effect is consistent across investigated methods. The convolutional neural network models developed with augmented data on average provided better performances compared to those developed using calculated molecular descriptors for both regression and classification tasks.
Psychosocial working conditions and depressive disorder: disentangling effects of job control from socioeconomic status using a life-course approach
Authors: Svane-Petersen Annemette Coop , Holm Anders , Burr Hermann , Framke Elisabeth , Melchior Maria , Rod Naja Hulvej , Sivertsen Børge , Stansfeld Stephen , Sørensen Jeppe Karl , Virtanen Marianna , Rugulies Reiner , Madsen Ida E. H. 
Published: September 2019

AbstractPurposeJob control, the combination of skill discretion and decision authority, is considered a central component of the psychosocial working environment. This longitudinal study examines the relation between job control and risk of incident depressive disorder using a life-course approach.MethodsWe analyze data from The Danish Work Life Course Cohort study, including all Danish individuals aged 15–30 who entered the Danish labor market during 1995–2009 and were free from depressive disorder at entry (955,573 individuals). We measured job control using a job exposure matrix. Depressive disorders were measured using information from nationwide registers of psychiatric in- and outpatient admissions. Using Cox regression models we estimated the prospective association between job control and risk of incident depressive disorders. Analyses accounted for a range of potential confounders prior to workforce entry including socioeconomic status in adolescence and parental psychiatric and somatic diagnoses prior to labor market entry, together with potential confounders in adulthood including income, education, and demographics.ResultsLower levels of past year job control were associated with a higher risk of depressive disorder after adjustment for all covariates (HR = 1.27, 95% CI 1.16–1.38). Results stratified by gender showed associations for both men (HR = 1.38, 95% CI 1.19–1.61) and women (HR = 1.19, 95% CI 1.08–1.32). Conclusions: Our findings suggest that the level of job control at work affects the risk of clinically diagnosed depressive disorder, and that this association is not due to confounding by socioeconomic status.
Zur Problematik der realistischen Beurteilung und Quantifizierung der Materialparameter für numerische Simulationen
Authors: Ladinig Tobias 
Published: September 2019

Zusammenfassung
Numerische Simulationen finden eine breite Anwendung in der gebirgsmechanischen Planung. Kritisch für die Aussagekraft des Ergebnisses ist die Qualität der Eingangsparameter. Die Materialparameter von Gebirge nehmen dabei eine besondere Stellung ein, weil die Erfassung und Beurteilung der Gebirgseigenschaften im Allgemeinen nicht ohne Annahmen und Abschätzungen möglich ist. Daraus folgt, dass die Materialparameter des Gebirges Unsicherheiten und Streubreiten aufweisen. Dieser Umstand wird anhand von einfachen und praktischen Beispielen diskutiert. Abschließend werden Möglichkeiten zum Umgang mit diesen Unsicherheiten besprochen. Diese sind Erfahrung aus dem fortschreitenden Abbau, das Prinzip der kontinuierlichen Planung und das Ausweisen einer Versagenswahrscheinlichkeit.
A Functional Approach to Vertical Turbulent Transport of Scalars in the Atmospheric Surface Layer
Authors: Clement Robert J. , Moncrieff John B. 
Published: September 2019

AbstractEddy covariance has been the de facto method of analyzing scalar turbulent transport data. To refine the information available from these data, we derive a simplified version of the turbulent scalar-transport equation for the surface layer, which employs a more explicit form of signal decomposition and dispenses with Reynolds averaging in favour of an averaging operator based on the relevant scalar-flux driving variables. The resulting method, termed functional covariance, provides five areas of improvement in flux estimation: (i) Better representation of surface fluxes through closer correspondence of turbulent exchange with variations in the driving variables. (ii) An approximate 25% reduction in flux uncertainty resulting from improved independence of turbulent-flux samples. (iii) Improved data retention through less onerous quality control (stationarity) testing. (iv) Improved estimation of low-frequency flux contributions through reduced uncertainty and avoidance of driving-variable nonstationarity. (v) Potential elimination of flux-storage estimation when state driving-variables are used to define the functional-covariance flux averaging. We describe the important considerations required for application of functional covariance, apply both functional- and eddy-covariance methods to an example dataset, compare the resulting eddy- and functional-covariance estimates, and demonstrate the aforementioned benefits of functional covariance.
Trace elements geochemistry in high-incidence areas of liver-related diseases, northwestern Ethiopia
Authors: Ahmed Jemal 
Published: September 2019

Abstract
This paper reports the results of trace elements geochemistry from Tigray national state, northwestern Ethiopia. The area is part of the Arabian-Nubian Shield, where the dominant exposure is low-grade metamorphic rocks and has a long history of liver-related diseases. The increase in the number of liver-related disease patients of the area has been an environmental health issue of national concern. The aim of the study is to determine the level of trace element concentrations and distributions in water and stream sediments of the area and identify the possible sources in relation to human health. Water, stream sediment and rocks samples (20 water, 20 stream sediments, and 6 rock samples) were collected in March 2011 and analyzed for major and trace element contents using ICP-MS, ICP-OES, ion Chromatography, and XRF methods. Bromine, aluminum, fluorine, arsenic, and nitrate values exceed the WHO maximum acceptable concentration (MAC) for drinking purpose. Bromine ranges from 0.11 to 1.48 mg/l show higher values in all samples, and fluorine ranges from 0.21 to 16.49 mg/l show higher values in 20% of the samples. Other trace elements are aluminum—30%, arsenic—10%, and nitrate (NO3)—10%, and they are examples of elements which have above MAC for drinking water. Selenium deficiency may be the other problematic element in the area for which its deficiency is associated with liver damage and heart muscle disorder. The concentration of cobalt and chromium exceeded world geochemical background value in average shale at most sample stations indicated that these stations were in potential risk.
Estimation of heterosis for yield-related traits for single cross and three-way cross hybrids of oilseed rape (Brassica napus L.)
Authors: Wolko Joanna , Dobrzycka Agnieszka , Bocianowski Jan , Bartkowiak-Broda Iwona 
Published: September 2019

AbstractRapeseed breeding programs are focused mainly on improving plant potential and seed yield. One of the ways to improve seed yield in oilseed rape is heterosis, which is hybrid vigor that results in a greater biomass, increased seed yield, and faster development. The purpose of this study was to estimate yield-related trait heterosis for single cross and three-way cross hybrids of winter oilseed rape (Brassica napus L.). A population of 60 doubled-haploid (DH) lines and two generations of hybrids were evaluated in field trials to assess six yield-related traits: plant height, number of branches per plant, number of siliques per plant, silique length, number of seeds per silique, and thousand seed weight. Heterosis effects for each trait were estimated by a comparison of the particular hybrid with: (1) the trait mean over both parents—mid-parent heterosis and (2) to the value of better parent—best-parent heterosis. Traits with clear positive heterosis and traits with varied heterosis were observed in this study. For the first group, we include plant height, silique length, and the number of seeds per silique—a large number of hybrids expressed significant positive heterosis for these traits, independent from the year of observations and the type of hybrid. For the second group, with varied heterosis, we can include the number of branches and siliques per plant and thousand seed weight. For these traits, hybrids exhibited both positive and negative significant heterosis, without a clear pattern for the years and types of hybrids.