Miracle-dz/UniFAR-FTUs huggingface dataset:
Effect of C on Vacancy Migration in α-Iron

Carbon atoms are always present in Fe-based materials, either as impurities even in high purity samples or as an intrinsic constituent in steels. Density Functional Theory calculations have been performed to study the interaction between C atoms and vacancies (V) in α-Fe. We find that the formation of VCn complexes is energetically favourable for n ≤ 3, with VC2 being the most stable one. The energy gain corresponding to the clustering reaction VCn-1 + C → VCn depends mainly on the strength of C-C covalent bonds. The vacancy diffusivity is shown to be significantly modified by the formation of vacancy-carbon complexes, exhibiting non-Arrhenius behaviour. Effective vacancy diffusion coefficients in α-Fe are calculated as a function of temperature and carbon content using a simplified thermodynamic model. The results are discussed in detail in the limiting case of excess of C with respect to vacancies.
First-principles theory of nitrogen aggregates in diamond

Abstract Local-density-functional theory is used to evaluate the structure, vibrational bands and electronic properties of two point defects in diamond a pair of adjacent substitutional N atoms and a vacancy surrounded by four N atoms. These defects are important as they are possible models of the A and B centres seen in type Ia diamond. For the A centre we find a N─N bond length of 2·14 A, an occupied electronic energy level near midgap and four infrared absorption bands with frequencies close to the experimental values. For the model of the B centre we find a N─C length of 1·49 A an occupied triplet electronic level within the gap consistent with the recent suggestion that the N9 absorption band is due to this defect and again vibratory modes in close agreement with experiment. These results provide strong evidence as to the validity of the models for the A and B centres.
Impact of an I-Corps Site Program on Engineering Students at a Large Southwestern University: Year 3

In today’s global market economy, equipping engineering students with a broader set of skills associated with an entrepreneurial mindset will empower them to create value for the companies they join or to launch their own startups. In recent years, institutions across the nation have been investing resources in developing maker spaces plus curricular and extracurricular programs to provide opportunities for students to acquire knowledge and skills, and pursue innovative ideas in a safe environment – while still in college. This study presented assessment data from a NSF I-Corps site program at a Southwestern university to understand the impact of the program on undergraduate and graduate engineering students’ knowledge, perceptions, and practice of entrepreneurship. In the four-cohort assessment data, participants indicated significantly increased confidence in value proposition, self-efficacy in entrepreneurship, and customer discovery, while maintaining high interest in entrepreneurship. Furthermore, the data indicated that participants with a GO decision (to continue pursuing their technology) had significantly higher perception on the current status of technology and business model than did participants with a no-GO/unsure decision. In addition, this study presented a new pilot program to be offered in spring 2020 and aimed to further enhance the I-Corps Site efforts on campus for broader impacts.
Effects of Web-Based Social Connectedness on Older Adults’ Depressive Symptoms: A Two-Wave Cross-Lagged Panel Study

Background Depressive symptoms are the most prevalent mental health concern among older adults (possibly heightened during the COVID-19 pandemic), which raises questions about how such symptoms can be lowered in this population. Existing research shows that offline social connectedness is a protective factor against depression in older adults; however, it is unknown whether web-based social connectedness can have similar effects. Objective This study investigates whether social connectedness on a support website protects older adults against depressive symptoms over the course of a year, above and beyond the protective effect of offline social connectedness. The secondary aim is to determine whether older adults with increased depressive symptoms are more likely to engage in social connectedness on this website. Thus, we examine depressive symptoms as both an outcome and predictor of web-based social connectedness to fully understand the chain of causality among these variables. Finally, we compare web-based social connectedness with offline social connectedness in their ability to lower depressive symptoms among older adults. Methods A total of 197 adults aged 65 years or older were given access to a social support website, where they were able to communicate with each other via a discussion forum for a year. Participants’ social connectedness on the web-based platform, conceptualized as message production and consumption, was measured using behavioral log data as the number of messages participants wrote and read, respectively, during the first 6 months (t1) and the following 6 months (t2) of the study. Participants self-reported their offline social connectedness as the number of people in their support networks, and they reported their depressive symptoms using the Patient Health Questionnaire-8 both at baseline (t1) and at 12-month follow-up (t2). To ascertain the flow of causality between these variables, we employed a cross-lagged panel design, in which all variables were measured at t1 and t2. Results After controlling for the effect of offline support networks at t1, web-based message consumption at t1 decreased older adults’ depressive symptoms at t2 (β=−.11; P=.02), but web-based message production at t1 did not impact t2 depressive symptoms (β=.12; P=.34). Web-based message consumption had a larger effect (β=−.11; P=.02) than offline support networks (β=−.08; P=.03) in reducing older adults’ depressive symptoms over time. Higher baseline depressive symptoms did not predict increased web-based message consumption (β=.12; P=.36) or production (β=.02; P=.43) over time. Conclusions The more messages older adults read on the web-based forum for the first 6 months of the study, the less depressed they felt at the 1-year follow-up, above and beyond the availability of offline support networks at baseline. This pinpoints the substantial potential of web-based communication to combat depressive symptoms in this vulnerable population. International Registered Report Identifier (IRRID) RR2-10.1186/s13063-015-0713-2
Combined Virtual Screening Strategies

The progress in chemical knowledge and synthetic technologies over the last fifty-years has dramatically increased the synthetic accessible chemical entities. Exploration of natural products rich chemodiversity has also expanded the vast chemical universe where medicinal chemist can pursue the identification of new therapeutic agents. Virtual Screening (VS) benefits from computational technology to explore the increasingly vast chemical universe in an efficient manner. The different VS approaches may be characterized by the computational and human time they require, from the highly automated and fast 2D-QSAR ligand-based VS to the more demanding 3D QSAR and target-based (docking) methodologies. Recently, several studies based on the integration of different VS approaches have been proposed, demonstrating that the hit recovery rate may be maintained (or even increased) with a substantial reduction of computing times. Combined virtual screening methodologies usually begin with the least-demanding approaches at the beginning of the VS process and progress to the more accurate, time consuming techniques in the last stages. This review discusses recent 2D/3D QSAR and ligand-based/target-based “synergistic” combinations that allow speeding-up the VS process, permitting accurate and efficient studies on large databases. The impact of the combination of different techniques on the chemical diversity of the compounds retrieved is also discussed.
Comparison Between Acridan Ester, Luminol, and Ruthenium Chelate Electrochemiluminescence

Transparent indium tin oxide (ITO) electrodes are attractive for use in electrochemiluminescence (ECL). In this work the ECL of an acridan ester (2′,3′,6′-trifluorophenyl 10-methylacridan-9-carboxylate), luminol, and a ruthenium chelate (ruthenium tris 2,2′-bipyridyl) are compared using ITO electrodes. The electrochemistry of all the compounds is described and related to their ECL mechanisms; three possible mechanisms for luminol ECL are described, and it is suggested that the currently accepted mechanism involving luminol and superoxide radicals may not always be correct. Maximum light emission in ruthenium chelate ECL occurs at 1.5 V (vs. Ag/AgCl), but potentials of more than 1 V have a corrosive effect on ITO. The effect of this limitation on ruthenium chelate ECL is discussed as part of a wider assessment of the advantages and disadvantages of ITO as an electrode material for ECL. The effects of pH and H2O2 concentration on ECL detection of the acridan ester and luminol in a planar flow cell are described. The limits of detection of the acridan ester and luminol were 65 pM and 72 pM, respectively.
Enthalpy of combustion of organo-metallic compounds measured with a vacuum-jacketed, rotating, aneroid calorimeter. The enthalpies of formation of germanium tetrabenzyl and di-germanium hexaphenyl

Germanium tetrabenzyl and di-germanium hexaphenyl have been burnt in a rotating aneroid combustion calorimeter. The standard enthalpies of combustion were respectively: ΔH°c=–3774.9±2.5 kcal mol–1; ΔH°c=–4782.4±2.5 kcal mol–1, which yield the standard enthalpies of formation : ΔH°f(GeBz4, c)= 52.5±2.5 kcal mol–1; ΔH°f(Ge2Ph6, c)= 106.7±2.5 kcal mol–1.
Distributed approximating functional fit of the H3 ab initio potential-energy data of Liu and Siegbahn

We report a distributed approximating functional (DAF) fit of the ab initio potential-energy data of Liu [J. Chem. Phys. 58, 1925 (1973)] and Siegbahn and Liu [ibid. 68, 2457 (1978)]. The DAF-fit procedure is based on a variational principle, and is systematic and general. Only two adjustable parameters occur in the DAF leading to a fit which is both accurate (to the level inherent in the input data; RMS error of 0.2765 kcal/mol) and smooth (“well-tempered,” in DAF terminology). In addition, the LSTH surface of Truhlar and Horowitz based on this same data [J. Chem. Phys. 68, 2466 (1978)] is itself approximated using only the values of the LSTH surface on the same grid coordinate points as the ab initio data, and the same DAF parameters. The purpose of this exercise is to demonstrate that the DAF delivers a well-tempered approximation to a known function that closely mimics the true potential-energy surface. As is to be expected, since there is only roundoff error present in the LSTH input data, even more .
Impact of Vitiligo on Quality of Life: A Cross-sectional Pilot Study from Western India

Background: Vitiligo is a common, acquired, mucocutaneous discoloration characterized by well-circumscribed depigmented macules. It has profound potential for cosmetic disfigurement and social stigma, which is an often neglected aspect of the disease. Objectives: To analyze the impact of vitiligo on the quality of life (Qol) of patients in western India and To determine the contributory factors. Methods: A cross-sectional, observational study was conducted at a tertiary care hospital on 60 patients with vitiligo (were enrolled after informed consent and ethical approval). Basic patient-related (age, gender, socioeconomic status, co-morbidities) and vitiligo-related variables (body surface area involved, stability, duration of disease, treatment modality) were noted. This information were collated with QoL using a standardized questionnaire, the Dermatology Life Quality Index (DLQI). Statistical analysis was performed using Spearman’s rank correlation coefficient, Pearson’s r, unpaired t-test (SPSS version 16). Results: Mean DLQI score of the study sample was 3.15 ± 4.2 (small effect on QoL). The mean DLQI score in females (3.97) was significantly higher than in males (1.92) (P = 0.046). Also, the DLQI demonstrated a significant positive correlation with body surface area involvement (Spearman’s correlation coefficient = 0.306) (P = 0.018). Other factors were not found to affect the DLQI. Conclusions: Various modifiable and non-modifiable factors influence the QoL of vitiligo patients. Gender- associated stigma may be alleviated by counseling and creating awareness, while the body surface area involvement may be addressed by instituting early and appropriate treatment. The clinician must be vigilant for any subtle signs of impairment of QoL to enable timely intervention.
Quantitative analysis of lamellar structures in brush polymer thin films by synchrotron grazing‐incidence X‐ray scattering

In this study, a grazing-incidence X-ray scattering (GIXS) formula was derived for lamellar structures formed in thin films supported on substrates, and a comprehensive numerical analysis was performed using the scattering formula. A quantitative analysis was conducted of lamellar structures formed in nanometre-scaled thin films of a brush polymer, poly[oxy(n-decylthio­methylen­yl)­ethylene], supported on silicon substrates, by GIXS measurements during cooling and subsequent heating, and data analysis was performed using the scattering formula. This analysis provided details (long period, sub-layers and their thicknesses, volume fraction, bristle paracrystal distortion factor, and orientation) of the lamellar structure with varying temperature that are not easily obtained using conventional techniques. Moreover, a molecular structure model and electron density profiles were established.
Strengthening Development of Rules As Code: Submission to the OECD’s OPSI on Cracking the Code

The draft working paper, 'Cracking the Code: Rulemaking for humans and machines' (OECD, May 2020), published by the OECD’s Observatory of Public Sector Innovation (OPSI), is intended to act as a 'primer', a resource for public servants across OECD Member States, to help them understand and engage with the concept of ‘Rules as Code’ and its implications. This paper, while generally very supportive of 'Cracking the Code', is a submission to OECD OPSI which makes 14 suggestions for further strengthening the concept and the implementation of 'Rules as Code' (RaC). The suggestions include support for: application of RaC to both conversion of existing legislation and application to new legislation; the use of declarative rules in knowledge-bases; continuing research on 'scaling up' legislative knowledge-bases; ensuring NGO involvement (including by LIIs); and acceptance that interpretation of open-textured terms usually cannot be avoided and must be accommodated. 'Cracking the Code' proposes six principles for successful development of RaC, and while we support them we suggest some major amendments In particular we argue that 'Appealability' does not provide sufficient governance over when automated decision-making should be used at all, and a broader 'Appropriate Application' principle may be needed. We also suggest two further principles, 'Sustainability' and 'Access to Legal Sources'.
Study of Multicenter Redox Molecules with Square Wave Voltammetry

An analytical explicit expression for the current obtained with the well-known multipulse technique square wave voltammetry (SWV), corresponding to the reversible reduction/oxidation of multicenter redox molecules whose centers may or may not interact, has been given in Appendix. This equation is valid for spherical electrodes of any size, including planar electrodes (r0 → ∞) and ultramicroelectrodes (r0 → 0) as limit cases, and it also permits us to deduce the behavior of these processes at the limit situations corresponding to small and great square wave amplitudes. For the sake of simplicity, we have analyzed the behavior of bicenter molecules, ranging from noninteracting centers, for which the square wave current obtained is twice that corresponding to a single E mechanism, to strongly interacting centers which present two successive and well-separated signals of one electron each. The results obtained here are easily extendable to molecules with any number of redox centers. The theoretical prediction.
Dielectric Properties and Dynamic Simulation of Water Bound to Titania/Silica Surfaces

Water adsorbed on titania/silica (TS) surfaces has been studied by dielectric spectroscopy (DS) in the 3-10 MHz frequency range at T = 120-300 K, thermally stimulated depolarization (TSD) at the same temperatures, 1 H NMR, and quantum chemical methods. The TSD spectra ofTS have only one relaxation maximum after sample heating at 400 K. The activation energies of depolarization (TSD) and polarization (DS) decrease at TiO 2 content increasing in TS. According to the TSD, DS, and 1 H NMR data, water adsorbed on the TS surfaces essentially in the interface region forms more weakly bound clusters than on the silica surfaces. Simulation of vibrational-rotational relaxation of the water molecules attached to the TS surfaces shows that the activation energy of rotation is a maximum for the molecules having donor-acceptor bonds, Me-OH 2 (Me = Si, Ti), in the complexes HO-Me-OH 2 + mH 2 O and it is minimum for one water molecule linked to the Ti-O(H)-Si bridge through a hydrogen bond.
A Review on Pharmacological Activities of Citrullus colocynthis (L.) Schrad

Plants are seen generally as resources for food and medicines by humans. Citrullus colocynthis is a decorative European plant. It belongs to the Cucurbitaceae family and is also called bitter apple and bitter cucumber. This plant is mostly found in Africa, Asia and many regions of Iran. In this article, Citrullus colocynthis was found to have antidiabetic, hypolipidemic, antineoplastic, antioxidant, anti-inflammatory, profibrinolytic, analgesic, antiallergic, antimicrobial, pesticidal and immunostimulant activity. It also has an effect on the reproductive system and fertility. This review suggests that Citrullus colocynthis has a broad spectrum of pharmacological activity, in which antidiabetic activity is prominent. It seems that more research is needed to evaluate these findings.
Simulation of Generation of High Pressure and Temperature in Metals under Shock Loading

Pressure and Temperature in different metals including radioactive materials behind converging shock waves, is simulated using generalized form of equation of state. Tait’s equation of state of metals, is valid for pressures of the range of few mega bars and takes into account only elastic pressures. At such high pressures, metal undergo phase change and normal equation of state no more is valid. At such pressures, temperature in metals becomes very high and thermal and excitation pressures dominate over elastic pressure. It is observed that as shock approaches the center of sphere, excitation pressure dominates elastic as well as thermal pressure.
Physicochemical Factors in the Dissolution of Thoria in Solid Nickel

AbstractMeasurements have been made of the thermodynamics and diffusivity of oxygen in dilute solution in nickel in the range 1050–1200° C. The dissolution of thoria in nickel was then studied by α-ray spectrometry in atmospheres of controlled oxygen partial pressure between 1295 and 1400° C. It was concluded that the rate-determining step in the dissolution process was the diffusion of thorium atoms in nickel, and that the presence of oxygen in solution in the metal enhanced this process.
Supercontinuum laser absorption spectroscopy in the mid-infrared range for identification and concentration estimation of a multi-component atmospheric gas mixture

In this paper, we first report the recent achievement of a mid-infrared supercontinuum fiber laser source in our laboratory. Using fluoride fibers, we have generated a wavelength supercontinuum covering the whole 2-3. 5μm range, and delivering a power spectral density of 0.3 mW/nm on a large spectral range. Experimental results are presented. This source can open opportunities for broadband remote sensing of multiple gas species in the atmosphere, especially above 3 μm, where numerous organic compounds have strong absorption signatures. Therefore, we consider a simple Supercontinuum Laser Absorption Spectroscopy (SLAS) experiment, and we develop a numerical case study above 3 μm, involving a multi-component gas mixture. We first describe a method for modelling noisy spectroscopic signals. Then we consider the inverse problem, and attempt to perform identification and quantitative estimation of the gas mixture. After showing the inapplicability of a direct multi-linear regression, we focus on processing methods that use complexity penalization principles, and show that they can address efficiently the identification/estimation problem. Among various penalization criteria, those based on Minimum Description Length (MDL) approaches are shown to perform particularly well. Finally, we apply these methods to preliminary experimental spectroscopic signals obtained with supercontinuum sources in our laboratory.
Control of plasma properties in capacitively coupled oxygen discharges via the electrical asymmetry effect

Using a combined experimental, numerical and analytical approach, we investigate the control of plasma properties via the electrical asymmetry effect (EAE) in a capacitively coupled oxygen discharge. In particular, we present the first experimental investigation of the EAE in electronegative discharges. A dual-frequency voltage source of 13.56 MHz and 27.12 MHz is applied to the powered electrode and the discharge symmetry is controlled by adjusting the phase angle θ between the two harmonics. It is found that the bulk position and density profiles of positive ions, negative ions, and electrons have a clear dependence on θ, while the peak densities and the electronegativity stay rather constant, largely due to the fact that the time-averaged power absorption by electrons is almost independent of θ. This indicates that the ion flux towards the powered electrode remains almost constant. Meanwhile, the dc self-bias and, consequently, the sheath widths and potential profile can be effectively tuned by varying θ. This enables a flexible control of the ion bombarding energy at the electrode. Therefore, our work proves the effectiveness of the EAE to realize separate control of ion flux and ion energy in electronegative discharges. At low pressure, the strength of resonance oscillations, which are found in the current of asymmetric discharges, can be controlled with θ.
Computer simulation studies of anisotropic systems. XVIII. Re-entrant phase separation in nematogenic mixtures of cylindrical and spherical particles

Addition of a solute composed of quasi-spherical molecules to a nematic liquid crystal is known to depress the nematic–isotropic transition temperature. A biphasic régime, consisting of coexisting nematic and isotropic phases, is also created at the transition. A molecular field theory of such mixtures, developed by Humphries and Luckhurst, predicts, in addition, the appearance of a re-entrant biphasic region following the nematic phase for a narrow range of compositions. This unusual re-entrant phase separation has not been observed for real nematogenic mixtures, presumably because the system freezes before the re-entrant phases can be formed. Here we report the observation of this biphasic régime for a model nematogenic mixture, formed from cylindrical and spherical particles, which was studied using the Monte Carlo technique of computer simulation. The particles are confined to the sites of a simple cubic lattice but still retain their rotational freedom; in consequence the mixture is unable to freeze in the conventional sense. The temperature variation of the heat capacity and the solute–solute radial distribution function reveal the predicted transition to the re-entrant biphasic régime. The internal energy and the second-rank orientational order parameter were also determined as a function of temperature. The predictions of the Humphries–Luckhurst theory are found to be in good qualitative accord with the results of the simulation.