Miracle-dz/UniFAR-FTUs huggingface dataset:
Determination of Dissociation Constants of Some Hydroxylated Benzoic and Cinnamic Acids in Water from Mobility and Spectroscopic Data Obtained by CE-DAD

In this study, the dissociation constants of a series of phenolic acids, including benzoic acid, four hydroxylated derivatives (p-hydroxybenzoic, protocatechuic, vanillic, and gallic), and four hydroxylated cinnamic acid derivatives (p-coumaric, caffeic, ferulic, and sinapinic) have been determined in water by capillary electrophoresis (CE) from the electrophoretic mobilities at different pH value. The pKa values have also been obtained from the absorbance spectra at the maximum of the electrophoretic peaks, which were measured with a diode-array detector (CE-DAD methodology). The pKa values obtained from both methodologies (CE and CE-DAD) have been compared with those previously published in the literature and also with the values predicted by the SPARC online pKa calculator.
APPLICATION OF POLYMER DISPERSED LIQUID CRYSTAL (PDLC) NEMATIC: OPTICAL-FIBER VARIABLE ATTENUATOR

Dispersions of liquid crystals in polymeric matrices (PDLC) are used as light Variable Optical Attenuators (VOAs). Electronically controllable VOAs play a crucial role for channel power equalizers in WDM systems. This article describes the theoretical model optimizing PDLC performance and the fabrication process utilizing the polymerization-induced phase separation (PIPS) method, and presents the optical attenuation (OA) and polarization dependence loss (PDL) characteristics versus fabrication conditions. Fabricated VOAs have a large attenuation range (10–30 dB) and low insertion loss (IL) at a 1.55 µm wavelength (0.5 dB). Depending on the fabrication parameters, the OA, IL, and PDL are optimized. This device needs an applied voltage V90 of 10 to 70 Vrms for 10–100 µm PDLC thickness. The flatness of the optical characteristics of this device has also been measured in the C+L band.
Quantifying Bias and Uncertainty in Historical Data Collections with Probabilistic Programming

The enhanced access to ever-expanding digital data collections and open computational methods have led to the emergence of new research lines within the humanities and social sciences, bringing in new quantitative evidence and insights. Any data interpretation depends critically on understanding of the scope and limitations in data collection, as well as on reliable downstream analysis. Quantitative analysis can complement qualitative research by providing access to overlooked information that is accessible only through systematic discovery and analysis of latent patterns underlying the available data collections. Probabilistic programming is an expanding paradigm in machine learning that provides new statistical tools for intuitive interpretation of complex data sets. This new paradigm stems from Bayesian analysis and emphasizes explicit modeling of the data generating processes and associated uncertainties. Despite its remarkable application potential, probabilistic programming has so far received little attention in computational humanities. We use a brief case study in computational history to demonstrate how probabilistic programming can be incorporated in reproducible data science workflows in order to detect and quantify bias in a widely studied historical text collection, the Eighteenth Century Collections Online.
Free-standing polyaniline–porous carbon nanofiber electrodes for symmetric and asymmetric supercapacitors

Polyaniline (PANI)–porous carbon nanofiber (PCNF) composites were generated by in situ polymerization of aniline on PCNFs for use as flexible, binder-less electrodes for high-performance supercapacitors. The effect of polymerization time on the electrode performance was studied by using symmetric cell configuration. Because of the high faradic current and good charge transfer between PCNFs and PANI, a maximum specific capacitance of 296 F g−1 and excellent rate performance were achieved for PANI–PCNF electrodes. PANI–PCNF electrodes also showed good capacitance retention (98%) after 1000 charge–discharge cycles. Furthermore, an asymmetric cell was successfully fabricated by using PANI–PCNF as the positive electrode and PCNFs as the negative electrode. Energy density and power density were improved significantly by using the asymmetric cell configuration. The resultant PANI–PCNF//PCNF asymmetric supercapacitor exhibited an energy density of 353 W h kg−1 with the power density of 609 W kg−1 at a current density of 1 A g−1.
Characterising pre-clinical sub-phenotypic models of Acute Respiratory Distress Syndrome: an experimental ovine study

The Acute Respiratory Distress Syndrome (ARDS) describes a heterogenous population of patients with acute severe respiratory failure. However, contemporary advances have begun to identify distinct sub-phenotypes that exist within its broader envelope. These sub-phenotypes have varied outcomes and respond differently to several previously studied interventions. A more precise understanding of their pathobiology and an ability to prospectively identify them, may allow for the development of precision therapies in ARDS. Historically, animal models have played a key role in translational research, although few studies have so far assessed either the ability of animal models to replicate these sub-phenotypes or investigated the presence of sub-phenotypes within animal models. Here, in three ovine models of ARDS, using combinations of oleic acid and intravenous, or intratracheal lipopolysaccharide, we demonstrate the presence of sub-phenotypes which qualitatively resemble those found in clinical cohorts. Principal Components Analysis and partitional clustering reveal two clusters, differentiated by markers of shock, inflammation, and lung injury. This study provides the first preliminary evidence of ARDS phenotypes in pre-clinical models and develops a methodology for investigating this phenomenon in future studies.
Enaminones in Heterocyclic Syntheses: Part 4. A New One‐Step Synthetic Route to Pyrrolo[3,4‐b]pyridine and Convenient Syntheses of 1,4‐Dihydropyridines and 1,1′‐(1,4‐Phenylene)bis(1,4‐dihydropyridine)

Reactions of cyano olefins with (i) enamino imides afforded novel pyrrolo[3,4-b]pyridines; (ii) enamino esters afforded new 1,4-dihydropyridines; and (iii) bisenamino ester afforded new 1,1′-(1,4-phenylene)bis(1,4-dihydropyridine). The new derivatives are planned as suggested drug candidates.
An Incremental Learning Approach for Physical Human-Robot Collaboration

Physical Human-Robot Collaboration requires humans and robots to perform joint tasks in a shared workspace. Since robot’s characteristic strengths are to cope well with high payloads, they are utilized to assist human operators during heavy pulling or pushing activities. A widely used sensor to detect human muscle fatigue and thus, to trigger an assistance request, is an Electromyography (EMG). Many previous approaches to process EMG data are based on training Machine Learning models offline or include a large degree of manual fine tuning. However, due to recent advances in Machine Learning such as incremental learning, there is an opportunity to apply online learning which reduces programming effort and also copes well with subject specific characteristics of EMG signals. Initial results show promising potential, yet, unveil a conflict between convergence time and classification accuracy.
On the dehydration mechanism of Mg(OH)2 by a high-energy electron beam

The dehydration process in Mg(OH)2 induced by high-energy electron irradiation is studied by in situ electron energy loss spectroscopy. During dehydration, both the low energy-loss spectra and the Mg L23 edge show the existence of partially oxidized Mg- or O-deficient MgO in the dehydrated products, which is not seen in the thermally dehydrated MgO. This indicates that the dehydration mechanism under the electron beam may be different from the mechanism involved in a thermal process.
A Non-Aqueous Asymmetric Cell with a Ti2C-Based Two-Dimensional Negative Electrode

A new MXene phase, Ti2C, obtained by aluminum extraction from Ti2AlC and exfoliation of the reaction product, was electrochemically studied vs. Lithium. Li-ions insertion into the 2-D structure was characterized by in situ XRD measurements. Additional electrochemical kinetic characterizations of Ti2C, using a cavity micro-electrode, showed that the electrochemical reactions involve two different phenomena: one diffusion-limited, the other not. A Ti2C/activated carbon asymmetric cell was assembled to highlight the high rate performance of the MXene. The cell was cycled between 1.0 V and 3.5 V, and showed good capacity retention during 1000 galvanostatic charge/discharge cycles at rates up to 10C.
Effect of human synovial fluid from osteoarthritis patients and healthy individuals on lymphatic contractility

The lymphatic system has been proposed to play a crucial role in the development and progression of osteoarthritis (OA). The synovial fluid (SF) of arthritic joints contains mediators of the inflammatory response and products of the injury to articular tissues, while lymphatic system plays a critical role in resolving inflammation and overall joint homeostasis. Despite the importance of both the lymphatic system and SF in OA disease, their relationship is still poorly understood. Here, we utilized SF derived from osteoarthritis patients (OASF) and healthy individuals (HSF) to investigate potential effects of SF on migration of lymphatic endothelial cells (LECs) in vitro, and lymphatic contractility of femoral lymphatic vessels (LVs) ex vivo. Both OASF and HSF treatments led to an increased migratory response in vitro compared to LECs treatment with media without serum. Ex vivo, both OASF and HSF treatments to the lumen of isolated LVs led to significant differences in the tonic and phasic contractions and these observations were dependent on the SF treatment time. Specifically, OASF treatment transiently enhanced the RFLVs tonic contractions. Regarding the phasic contractions, OASF generated either an abrupt reduction after 1 hr of treatment or a complete cease of contractions after an overnight treatment, while HSF treatment displayed a gradual decrease in lymphatic contractility. The observed variations after SF treatments suggest that the pump function of lymphatic vessel draining the joint could be directly compromised in OA and thus might present a new therapeutic target.
Ti L-spectrum XANES and electron structure of the system Ti-Al-C

The electron structure and Ti L-absorption edge in the system Ti-Al-C have been studied theoretically using the local coherent potential of the multiple scattering theory. The calculated local partial electron density of states of Ti made it possible to study the influence of Al on the electron structure of this material and its Ti Ti L-absorption spectrum. It was shown that in the ternary system comparing with the binary titanium carbide the first maximum of the titanium unoccupied d-states nearly disappeared and the intensity of the second one fell more than twice. These calculations are in a good correspondence with the experimental TI L-Spectra and indicate that the contribution of Ti s-states to XANES can be neglected.
A quantum model for water: Equilibrium and dynamical properties

Path integral molecular dynamics and centroid molecular dynamics have been applied to study and modify an empirical flexible model for water, the simple point charge/flexible (SPC/F) model. The quantum structural, thermodynamic and dynamical properties have been calculated and compared to their classical counterparts, as well as to experiment. The path integral molecular dynamics simulations demonstrate that the quantum liquid is less structured and exhibits less hydrogen bonding than its classical analog. Quantization also leads to a lower dielectric constant, relative to the corresponding classical value. Centroid molecular dynamics has been used to calculate single molecule time correlation functions, the Debye dielectric relaxation correlation function, and the power spectrum for the quantum model. These time correlation functions decay more rapidly than the classical ones, indicating that nuclear rotational tunneling occurs in the liquid. The power spectrum of the quantized liquid also exhibits red shifted bend and stretch frequencies relative to the classical model. A modification of the parametrization of the harmonic intramolecular potential for the simple point charge/flexible (SPC/F) model is suggested and tested in order to improve the dielectric properties as well as the values of the vibrational frequencies. The quantum simulation of the modified water model, called SPC/F2, gives better agreement with the experimental IR spectrum of water and the measured value of the dielectric constant. However, the self-diffusion constant for the modified SPC/F model is still somewhat too large relative to experiment. In addition, the NMR rotational time constant is too small compared to experiment. While these discrepancies leave room for future modifications (e.g., including electronic polarizability), the model represents the first parametrization of an empirical flexible water potential explicitly developed for quantum path integral simulations.Path integral molecular dynamics and centroid molecular dynamics have been applied to study and modify an empirical flexible model for water, the simple point charge/flexible (SPC/F) model. The quantum structural, thermodynamic and dynamical properties have been calculated and compared to their classical counterparts, as well as to experiment. The path integral molecular dynamics simulations demonstrate that the quantum liquid is less structured and exhibits less hydrogen bonding than its classical analog. Quantization also leads to a lower dielectric constant, relative to the corresponding classical value. Centroid molecular dynamics has been used to calculate single molecule time correlation functions, the Debye dielectric relaxation correlation function, and the power spectrum for the quantum model. These time correlation functions decay more rapidly than the classical ones, indicating that nuclear rotational tunneling occurs in the liquid. The power spectrum of the quantized liquid also exhibits red s.
A quadratic model captures the human V1 response to variations in chromatic direction and contrast

An important goal for vision science is to develop quantitative models for the representation of visual signals at post-receptoral sites. To this end, we develop the quadratic color model (QCM) and examine its ability to account for the BOLD fMRI response in human V1 to spatially-uniform temporal chromatic modulations, systematically varying in their chromatic directions and contrasts. We find that the QCM explains the same, cross-validated variance as a conventional GLM, with far fewer free parameters. The QCM generalizes to allow prediction of V1 responses to a large range of modulations. We replicated the results for each subject and find good agreement across both replications and subjects. We find that within the LM cone contrast plane, V1 is most sensitive to L-M contrast modulations and least sensitive to L+M contrast modulations. Within V1, we observe little to no change in chromatic sensitivity as a function of eccentricity.
Development and application of a ReaxFF reactive force field for oxidative dehydrogenation on vanadium oxide catalysts (The Journal of Physical Chemistry A (2008) 112C)

We have developed a new ReaxFF reactive force field to describe accurately reactions of hydrocarbons with vanadium oxide catalysts. The ReaxFF force field parameters have been fit to a large quantum mechanics (QM) training set containing over 700 structures and energetics related to bond dissociations, angle and dihedral distortions, and reactions between hydrocarbons and vanadium oxide clusters. In addition, the training set contains charge distributions for small vanadium oxide clusters and the stabilities of condensed-phase systems. We find that ReaxFF reproduces accurately the QM training set for structures and energetics of small clusters. Most important is that ReaxFF describes accurately the energetics for various oxidation states of the condensed phases, including V2O5, VO2, and V2O3 in addition to metallic V (V0). To demonstrate the capability of the ReaxFF force field for describing catalytic processes involving vanadium oxides, we performed molecular dynamics (MD) simulation for reactions of a .
Verify&Revive: Secure Detection and Recovery of Compromised Low-end Embedded Devices

Tiny and specialized computing platforms, so-called embedded or Internet of Things (IoT) devices, are increasingly used in safety- and privacy-critical application scenarios. A significant number of such devices offer limited or no security features, making them attractive targets for a wide variety of cyber attacks, exemplified by malware infestations. One key component in securing these devices is establishing a root of trust, which is typically attained via remote attestation (RA), a security service that aims to ascertain the current state of a remote device and detect any malicious tampering. Although several (software-based, hardware-based, and hybrid) RA approaches have been proposed to address this problem, two main issues remain, regardless of the type of RA. First, all but one of the existing RA approaches are vulnerable to Time-Of-Check Time-Of-Use (TOCTOU) attack, where a transient malware may infect the corresponding embedded device between two consecutive RA routines without being detected. Second, little attention has been devoted to efficiently and securely rescuing devices that are determined to be compromised, increasing the maintenance cost of IoT deployments, especially in industrial control systems, where (re-)deploying a new device is often a cost-sensitive operation. Motivated by the fact that many low-end devices neither support hardware-based RA nor can afford hardware modifications required by hybrid approaches, we tackle the aforementioned issues by proposing Verify&Revive, the first reliable pure-software approach to remote attestation with recovery techniques, targeting the low-end range of IoT devices. It consists of two components: Verify and Revive. Verify is a TOCTOU-secure RA scheme with a built-in secure erasure module that is automatically executed as a countermeasure in case of detection of a malware infection on the IoT device. Revive is a secure code update scheme that is executed upon request to install regular updates or as a recovery technique to restore the last benign settings of the cleaned, yet non-functioning, IoT device. A proof of attestation, erasure, and update/recovery is obtained relying on trustworthy software, leveraging and extending a formally-verified software-based memory isolation technique, called the Security MicroVisor (SμV). We implement and evaluate Verify&Revive on industrial resource-constrained IoT devices, showing very low overhead in terms of a memory footprint, performance, and battery lifetime.
PEOA New Hydrate Inhibitor Polymer

The hydrate inhibition potential of four different polymers has been tested in a high-pressure apparatus at high pressures and low temperatures. Aqueous polymer solutions were prepared at 1 wt % concentration. Methane (99.5% purity) was used as hydrate former gas. Hydrate formation rates of the tests were calculated to decide the best inhibitors. A known hydrate inhibitor, poly(N-vinylpyrrolidone) (PVP) and a water-soluble thermoplastic polymer (PEO) were determined the best kinetic inhibitors among them.
Structure regulation of silk fibroin films for controlled drug release

Silk fibroin (SF) films were prepared using a casting method and the change of secondary structure and crystal structure owing to treatment with ethanol–water mixtures of different concentrations was investigated by Fourier transform infrared spectroscopy and X-ray diffraction. The results were used to reveal the influence of structure of SF matrix on the release kinetics of drug compounds incorporated. It was found that the content of silk II structure, constituted by β-sheet, first increased and then decreased with increasing ethanol concentration ranging from 50 to 90%, reaching a maximum around 70–80%. The release kinetics of Rhodamine B, a model compound for small molecule drugs, was described by Peppas equation. The results indicated that Rhodamine B released from SF films via Fickian diffusion mechanism and the diffusional exponent n increased with increasing β-sheet content in the matrix. The experimental data had a good linear fit, suggesting that the silk II crystal could be used as a natural regulator for drug release from SF material. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Qualidade da água em viveiro de Tilápia do Nilo (Oreochromis niloticus): caracterização diurna de variáveis físicas, químicas e biológicas, São Paulo, Brasil

Este estudo teve por objetivo descrever o comportamento de variaveis fisicas, quimicas e biologicas da agua de um viveiro de engorda de tilapias ( Oreochromis niloticus , Linnaeus) no periodo diurno, visando contribuir com um melhor entendimento da dinâmica e metabolismo desse sistema e sugerir propostas de manejo para melhoria da qualidade da agua e da producao dos organismos. Realizou-se o levantamento de variaveis limnologicas de viveiro de piscicultura, avaliando-se as oscilacoes diurnas (6h as 20h, a cada 2 horas de intervalo) do oxigenio dissolvido e sua porcentagem de saturacao, do gas carbonico livre, da temperatura da agua, da transparencia da agua, da condutividade eletrica, da turbidez, dos solidos totais em suspensao, da alcalinidade total e do pH, da luminosidade incidente na agua, das series de nitrogenio e fosforo e da clorofila a . Elevados valores de fosforo e de clorofila a foram obtidos, verificando-se relacao de causa e efeito, ou seja, a entrada de fosforo promoveu o crescimento das algas. A principal fonte de fosforo adveio do arracoamento diario. Constatou-se forte relacao da dinâmica do oxigenio dissolvido e gas carbonico com a atividade fotossintetica das algas e, consequentemente, da variacao da luminosidade ao longo do dia. As oscilacoes de pH obtidas relacionaram-se ao baixo poder tampao da agua, em funcao dos baixos valores de alcalinidade total. Pode-se sugerir a aplicacao de calcario agricola com a finalidade de melhorar o poder tampao da agua. O uso de aeradores apos as 20h tambem e recomendado. Palavras-chave : Limnologia. Qualidade da agua. Viveiro de piscicultura. Tilapia do Nilo.
Optimized cryo-EM data-acquisition workflow by sample-thickness determination

Sample thickness is a known key parameter in cryo-electron microscopy (cryo-EM) and can affect the amount of high-resolution information retained in the image. Yet, common data acquisition approaches in single particle cryo-EM do not take it into account. Here, we demonstrate how the sample thickness can be determined before data acquisition, allowing to identify optimal regions and restrict automated data collection to images with preserved high-resolution details. This quality over quantity approach, almost entirely eliminates the time- and storage-consuming collection of suboptimal images, which are discarded after a recorded session or during early image processing due to lack of high-resolution information. It maximizes data collection efficiency and lowers the electron microscopy time required per dataset. This strategy is especially useful, if the speed of data collection is restricted by the microscope hardware and software, or if microscope access time, data transfer, data storage and computational power are a bottleneck. Synopsis Sample thickness is a key parameter in single particle cryo-electron microscopy. Determining sample thickness before data acquisition allows to target optimal areas and maximize data output quality of single particle cryo-electron microscopy sessions. Scripts and optimized workflows for EPU and SerialEM are presented and available as open-source.