Miracle-dz/UniFAR-FTUs huggingface dataset:
Defect chemistry of lone-pair semiconductors

Abstract A chemical-bond approach reveals the possibility of several unusual bonding configurations that have relatively low energy in materials with lone-pair valence electrons. Valence-alternation pairs (V.A.P.) are the lowest energy charged defects. The interconversion between positive and negative centres is described in detail. The nature of V.A. P.s in pnictides (group V elements) is discussed. The possibility that valence-alternation centres can form intimate or bound pairs is explored. It is pointed out that certain unusual bonding configurations (configuration distortions) arise even in an ideal lone-pair material. It is stressed that the unusual bonding configurations discussed are a result of the special bonding in lone-pair materials and are, therefore, expected to arise in crystals as well as amorphous materials.
Physicochemical Evaluation of Nanoparticles Assembled from Poly(lactic acid)−Poly(ethylene glycol) (PLA−PEG) Block Copolymers as Drug Delivery Vehicles

Nanoparticles assembled from poly(d,l-lactic acid)−poly(ethylene glycol) (PLA−PEG) block copolymers may have a therapeutic application in site-specific drug delivery. A series of AB block copolymers based on a fixed PEG block (5 kDa) and a varying PLA segment (2−110 kDa) have been synthesized by the ring-opening polymerization of d,l-lactide using stannous octoate as a catalyst. These copolymers assembled to form spherical nanoparticles in aqueous media following precipitation from a water-miscible organic solvent. 1H NMR studies of the PLA−PEG nanoparticles in D2O confirmed their core−shell structure, with negligible penetration of the hydrated PEG chains into the PLA core. The influence of the PLA block molecular weight on the hydrodynamic size and micellar aggregation number of the assemblies was determined by dynamic and static light scattering techniques. The hydrodynamic radius of the PLA−PEG 2:5−30:5 nanoparticles was solely dependent on the copolymer architecture and scaled linearly as NPLA1/3, wh.
Electrolyte Status in Preeclampsia

CONCLUSION: The study shows reduced levels of serum calcium, magnesium, potassium and increased level of sodium in patients of preeclampsia as compared to the normal pregnant women. Increased sodium in vascular tissue enhanced vasoconstriction in preeclampsia. Hypocalcemia, hypomagnesemia, hypokalemia and hypernatremia seen in the preeclamptic women may be responsible for the vascular pathology associated with onset of preeclampsia. Hence adjuvant supplementation of calcium, magnesium, potassium with dietary restriction of sodium may pr event further progression of preeclampsia.
Modélisation, classification et annotation d'images partiellement annotées avec un réseau Bayésien

Dans cet article, nous proposons un modele graphique probabiliste pour representer des images partiellement annotees. Nous considerons une image comme partiellement annotee si elle ne possede pas le nombre maximal de mots-cles disponibles pour une image dans la verite-terrain. Ce modele est utilise pour classifier des images et etendre automatiquement les annotations existantes a de nouvelles images, en prenant en compte les eventuelles relations semantiques entre mots-cles. La methode proposee a ete evaluee en classification visuo-textuelle et en extension automatique d'annotations. La classification visuo-textuelle correspond a la classification effectuee en utilisant a la fois l'information visuelle et l'information textuelle, quand elle est disponible. Les resultats experimentaux, obtenus a partir d'une base de plus de 30000 images, montrent une amelioration de 50.5% en moyenne, en terme de taux de reconnaissance, par rapport a la classification basee sur l'information visuelle seule. La prise en compte des eventuelles relations semantiques entre mots-cles ameliore le taux de reconnaissance de 10.5% en moyenne et le taux de bonnes annotations de 6.9% en moyenne. Enfin, la methode proposee s'est montree competitive, experimentalement, avec des classificateurs de l'etat de l'art.
Nonlinear ARMA-GARCH Forecasting for S&P500 Index based on Recurrent Neural Networks

A nonlinear ARMA-GARCH model is proposed for forecasting daily stock market returns. The only difference from the linear ARMA-GARCH is the conditional mean component. Two parameters are added and the hyperbolic tangent function is utilized to give a nonlinearity. The nonlinear ARMA-GARCH is solved by the recurrent neural network concept. In order to show the practical applicability of the proposed nonlinear ARMA-GARCH model, daily algorithmic trading is carried out with historical S&P500 daily closing index from 1950 to 2018. It is shown that the proposed nonlinear ARMA-GARCH model out-performs the linear ARMA-GARCH model in terms of financial and statistical measures.
A new and facile strategy for the one-pot fabrication of luminescent gold nanoclusters and their prospective application

A simple, novel, green, economic, environment friendly and convenient one-pot fabrication of luminescent gold nanoclusters, incorporating an aqueous extract of the peels of Allium cepa L. , otherwise considered as a common household waste material, has been described. The optimal experimental conditions including concentrations of Allium cepa L. extract and different reaction temperatures have been investigated in detail. The nanoclusters were characterized by various spectroscopic techniques, such as ultra-violet spectroscopy (UV-vis), photoluminescence spectroscopy (PL), Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction pattern (SAED), Fourier-transform infrared spectra (FTIR), X-ray diffraction spectroscopy (XRD) and scanning electron microscopy with energy dispersive X-ray (SEM-EDX). spectroscopic results revealed the formation of clusters with an average diameter in the range of 4–9 nm and depicted a fluorescence emission spectrum at 640 nm. Furthermore, the EDX pattern also revealed the formation of gold nanoclusters. The prepared nanoclusters were effectively utilized for the remediation of two carcinogenic and lethal textile dyes, rose bengal and methylene blue from aqueous solution. Approximately, 98.9 and 95.1% of rose bengal and methylene blue dye were degraded within 180 and 145 min using the synthesized gold nanoclusters, respectively. Additionally, the exhausted nanoclusters were regenerated and their photo catalytic capability was evaluated for three continuous rounds of cycling. The exhausted nanoclusters and the intermediates of the degradation process were respectively analysed using TEM, SAED and LC-MS techniques. The catalytic efficiency of the fabricated nanoclusters was also evaluated by conversion of 4-nitro phenol to 4-amino phenol in the presence of sodium borohydride in an aqueous medium. It was observed that about 97.3% of 4-nitro phenol was reduced within 70 min. Furthermore, the fabricated clusters were also found to inhibit the growth of a common human pathogenic bacterium, Escherichia coli. Hence, the present study has unfastened a pioneering way for synthesizing Au NCs and their applicability for the remediation of hazardous compounds and their potential as antibacterial agents.
First Observation of Negative Differential Resistance in Surface Tunnel Transistors

Negative differential resistance (NDR) due to an interband tunneling has been observed at room temperature for the first time in a Surface Tunnel Transistor (STT) under forward-bias conditions. To produce clear NDR characteristics, the electron density in the channel was designed to be high enough to induce band overlap at the channel/drain junction. In order to increase the tunneling current further, a channel doped structure, in which a thin n+-GaAs layer was inserted between a p+-GaAs layer (drain) and an i-GaAs layer, was proposed. This channel doped STT exhibited a peak current density of 8 µ A/µ m, which is 280 times larger than that of the conventional STT.
PRACTICAL IDENTIFICATION ANALYSIS OF HALDANE KINETIC PARAMETERS DESCRIBING PHENOL BIODEGRADATION IN BATCH OPERATIONS

The capability of three techniques, “initial specific growth rates (IGRA)”, “substrate depletion data from a single batch experiment (SDES)”, and “growth rates during incubation in batch experiment (GRIB)”, were evaluated with respect to accurately determining Haldane model parameters with a few batch studies by analyzing the identifiability of Haldane kinetic constants estimated by each of these three methods. Both IGRA and SDES are conventional techniques; they use the initial specific growth rate from batch degradation assays, and substrate depletion measurements in a single batch degradation experiment, respectively, as the basis for estimating parameters. The GRIB technique, first proposed in this study, uses specific growth rates during incubation. Six batch experiments were conducted, in which both residual phenol and biomass during the period of incubation were measured to generate data to be used as a basis for parameter estimation. Haldane parameters estimated by IGRA method appear to have a high average correlation coefficient (0.950) and significant slenderness of joint confidence regions, indicating that the derived constants are not practically identifiable. The parameters estimated by the SDES method are not identifiable either, because the average parameter correlation coefficients reach 0.994-0.999. However, the GRIB method, when two batch experiments with initial phenol concentrations of 50 and 400 mg L -1 were used, could give highly identifiable parameters. The best parameters obtained by the GRIB method were maximum specific growth rate μmax = 0.34 h -1 , half-velocity concentration Ks = 1.8 mg L -1 and inhibition constant Ki = 340 mg L -1 . The corresponding average correlation coefficient was as low as 0.693 and the slenderness of joint confidence regions were considerably reduced. The findings of this study suggest that GRIB is superior to IGRA and SDES techniques because it is associated with the ability to give parameters having high identifiability.
Optimizing the sparging condition and membrane module spacing for a ZW500 submerged hollow fiber membrane system

Abstract The present study characterized the surface shear forces induced by sparging for different sparging conditions (i.e. continuous, alternating and pulse) and the membrane module configurations (i.e. spacing). The root mean square (RMS) of surface shear forces induced by gas sparging, which has been reported to be related to the extent of fouling control in membrane systems, were relatively similar for continuous, alternating and pulse sparging. Considering that pulse sparging uses approximately half of the volume of sparged gas than continuous or alternating sparging, the results suggest that pulse sparging is the best sparging approach. The RMS of surface shear forces were substantially higher for the wide module spacing than for the standard (i.e., narrow) module spacing, indicating that fouling control can likely be significantly improved by simply increasing the distance between the membrane modules.Because of the heterogeneous distribution of surface shear forces and sparged bubbles, it is ess.
Comparison of properties of acrylic–polyurethane hybrid emulsions prepared by batch and semibatch processes with monomer emulsion feed

Aqueous acrylic–polyurethane hybrid emulsions were prepared by batch and semibatch polymerization of acrylic monomer mixtures (butyl acrylate, methyl methacrylate and acrylic acid) in the presence of polyurethane dispersion. The acrylic component was introduced in the monomer emulsion feed. The weight ratio between acrylic and polyurethane components was varied to obtain different emulsion properties, microphase structure and mechanical film properties. Scanning electron microscopy, average particle size and molecular weight measurements were performed to characterize the latex systems. Mechanical properties were examined by measuring Koenig hardnesses of dried films. The average particle size increased with the acrylic/polyurethane ratio. Particles of larger than average size and, to some extent, higher than average molecular weights by batch process were formed. Koenig hardnesses decreased with increasing acrylic/polyurethane ratio. Properties of emulsions synthesized by semibatch processes were compared with the results reported for a different polyurethane dispersion. Copyright © 2003 Society of Chemical Industry
Phonons in semiconductors

Abstract It is obvious that the title of this article encompasses an area too vast to be adequately covered in a single review paper. Thus, we hasten to remark at the outset that the primary topic to be dealt with here is the relation between the crystal dynamics, on the one hand, and the basic interactions between the valence electrons and ion cores in semiconducting crystals, on the other. In this sense, this review is essentially an extension and updating of Cochran's recent review article in this series1 with special emphasis on semiconductors and covalently bonded solids.
The role of Alb3 and its homologs in the insertion and assem- bly of thylakoid membrane proteins

Beatrix Dünschede and *Danja Schünemann Molecular Biology of Plant Organelles, Ruhr-University Bochum, 44780 Bochum, Germany; * Correspondence to: danja.schuenemann@rub.de Members of the YidC/Oxa1/Alb3 protein family exhibit a wide phylogenetic distribution. They are found in the plasma membrane of bacteria, the inner membrane of mitochondria and the thylakoid membrane of chloro­ plasts, where they are involved in the biogenesis of membrane proteins. Detailed studies have demon­ strated that members of the YidC/Oxa1/Alb3 family can interact with a variety of substrate proteins and perform versatile functions. Depending on the sub­ strate protein, the YidC/Oxa1/Alb3 proteins can func­ tion as insertases or assist in folding and assembly of the proteins. This review focuses on Alb3 and its homo­ logs in higher plants, green algae and cyanobacteria, and describes their role in the biogenesis of photosyn­ thetic complexes. Journal of Endocytobiosis and Cell Research (2011) 19‐25 Category: Mini‐review eywords: YidC/Oxa1/Alb3 protein family, translocase, K insertion and assembly of membrane proteins, chloroplast Received: 09 February 2011; Accepted: 14 February 2011 ____________________________________________________________________
Fabrication and characteristics of p-type Cu2O thin films by ultrasonic spray-assisted mist CVD method

P-type cuprous oxide (Cu2O) thin films were fabricated by an ultrasonic spray-assisted mist chemical vapor deposition (mist CVD) method. Copper(II) acetylacetonate was used as a precursor and deionized water was used as a solvent. Cu2O was grown at a temperature of 350 °C and the films were gradually changed from Cu2O to CuO by increasing the growth temperature. The Cu2O film grown at 350 °C showed p-type conductivity with a carrier concentration of 3.3 × 1015 cm−3 and a Hall mobility of 0.2 cm2·V−1·s−1.
Electronic Structure of a Rigid Cyclic Diamide

Interest in the electronic structure of amides and polypeptides arises in part because optical spectroscopy such as electronic circular dichroism (CD) may be readily used to monitor conformational changes of peptides and proteins in solution. Our current, albeit somewhat incomplete, understanding of the relationship between polypeptide conformation and CD spectra has come in part from experimental and theoretical studies of model systems such as cyclic diamides. In this paper, we study the interactions between amide groups in a bridged cyclic diamide, diazabicyclo[2.2. 2]octane-3,6-dione, through the measurement of its infrared (IR) and ultra-violet (UV) absorption and electronic CD spectra and through ab initio calculations of its electronic structure. The particular rigidity of the bridged cyclic diamide removes ambiguity regarding the conformation of the molecule in solution, which must remain close to the structure determined by X-ray crystallography. The theoretical study has been performed using the .
The effect of service failure severity and agreeableness on switchover intention mediated by consumer forgiveness: a study on consumers of bukalapak

E-commerce keeps growing and developing all over the world. The number of online shopping sites is increasingly over time. The number of ecommerce users in Indonesia keeps increasing and it is expected to reach 43.9 million people by 2022. There are a lot of benefits for companies and users created by e-commerce; nevertheless, it also had disadvantages and serious problems. There are so many service failures that experienced by the customers of the e-commerce. The object of study is Bukalapak because based on the observation; it found that many service failures occurred. The main objective of this study is to examine the effect of service failure severity and agreeableness on consumer switchover intention with the mediating role of consumer forgiveness in the aftermath of service failure. The study is used non-probability sampling method, which is convenience sampling. In total, 190 consumers of Bukalapak in Indonesia were given a hypothetical service failure situation and their response was collected through an online survey. The findings reveal that service failure severity has a direct positive effect on switchover intention. Agreeableness is significantly positively related to switchover intention. Consumer forgiveness cannot be a mediator between service failure severity and agreeableness toward switchover intention. Keyword: Service Failure Severity, Agreeableness, Consumer Forgiveness, Switchover Intentions
A Study of the Relationship Between Dye Absorption and Cotton Fiber Properties at Equilibrium

The relation between cotton fiber properties and dye absorption at equilibrium has been studied for nine cotton samples representing a large range of fiber properties. The absorption was studied both for mercerized and unmercerized cotton samples. A relationship was found to exist between dye absorption at equilibrium and the Micronaire and maturity of American Upland type cotton. A linear relationship was found to exist between maturity and dye absorption at equilibrium. The barium hydroxide absorption also was determined ; similar results were obtained.
Conformation and dynamics of ethylated DNA

N-nitroso compounds are known to modify normal DNA bases chemically and result in mutations which are either corrected by repair proteins or lead to misreading of the code and possibly carcinogenesis. In order to model the conformation of these modified sequences, we have used molecular dynamics simulations which are commonly applied to the study of normal oligonucleotide sequences. As part of this study, we have extended the AMBER force field to allow for the modified base O6-ethylguanine (O6-EtG) in the self-complementary d(CGCG*AGCTCGCG) duplex. Our results show that the AMBER force field produces stable oligonucleotide double helices over 2400 ps. The modified sequence with ethylguanine: cytosine base pairs leads to local disruption of the base pair because of the chemical modification of the guanine base but all other base pairs retain their normal conformation. The modified base pair has only two hydrogen bonds and adopts the so-called wobble conformation. In principle, there are two likely alkyl group conformations which can exist in the duplex, namely the trans,trans-ethylguanine (t,t-EtG) and the cis,trans-ethylguanine (c,t-EtG). The t,t-EtG sequence has a very similar equilibrium structure to the normal sequence whereas the c,t-EtG helix unwinds resulting in a helix which is one and a half times its original length. This change in conformation, together with other thermodynamic and energetic properties, indicates that c,t-EtG is less stable than t,t-EtG when paired with cytosine. The resulting structural changes are therefore factors that could be used in the recognition process prior to the repair.
Silver(I) affinities of amides: a combined ab initio and experimental study

The interaction of Ag+ with amides was studied through prototypical systems mimicking the binding of Ag+ to the peptide bond. The Ag+ binding affinities (energies) of formamide, N-methylformamide, N,N-dimethylformamide, acetamide, N-methylacetamide and N,N-dimethylacetamide were determined by the mass spectrometric kinetic method to be 162, 179, 193, 181, 198 and 208 kJ mol−1, respectively, with an estimated uncertainty of ±11 kJ mol−1. The relative stability of different possible Ag+ binding modes was investigated effectively at the ab initio CCSD(T)/[HW(f),6-31+G(d)] level of theory. The absolute theoretical affinities are in good general agreement with the experimental values, even though calculated values tend to be too high by an average of 10 kJ mol−1. The theoretical results show that Ag+ binds preferentially to the amide carbonyl oxygen, whereas monodentate binding to the amino nitrogen, or bidentate binding to both oxygen and nitrogen, are about 40 to 60 kJ mol−1 less stable. Methyl substitution at the amide carbon and amino nitrogen enhances the Ag+ affinity by increasing the molecular polarizability of the amide. The effects of C-methyl and N-methyl substitution on Ag+ binding at the amide carbon and amino nitrogen are found to be significantly different and this difference is discussed.
Bilayer structure of glycolipid crystals. Thermal stability of the crystal and state of the alkyl chain

The role of alkyl chains in the stabilization of a bilayer structure of glycolipids in the crystalline state has been studied for a series of methyl 6-O-acyl-β-D-glucopyranosides and methyl 6-O-acyl-α-D-galactopyranosides. Thermal properties and crystal structures of these glycolipids with an odd number of alkyl carbon atoms in the acyl moiety have been investigated by thermal analysis and X-ray methods. The melting temperatures of methyl 6-O-acyl-β-D-glucopyranosides, which are lower than those of the corresponding methyl 6-O-acyl-α-D-galactopyranosides, decrease with increasing number of alkyl carbon atoms from one to seven, but increase for longer alkyl chains. The α-galactosides show only a monotonic decrease in melting temperature with increasing alkyl chain length. In the crystals, the molecules form a bilayer structure with interdigitated alkyl chains. The arrangement of sugar moieties in the crystals differs between the β-glucosides and the α-galactosides, but they are almost the same among sugar derivatives with various alkyl chain lengths. The packing of the acetyl moiety in a crystal of methyl 6-O-α-D-galactoside is different from that of the other α-galactoside derivatives with longer alkyl chains. The carbonyl oxygen atom causes steric hindrance with adjacent alkyl chains, and such unfavorable intermolecular contact explains the relatively low thermal stability of the crystal. On the other hand, the contribution of the β-glucoside to thermal stability is ascribed to the well-ordered packing of the long alkyl chain moiety.
Copper−Silica Nanocomposites Tailored by the Sol−Gel Route

Nanocomposite silica glassy layers (host) containing copper-based species (guest) were developed and tailored by the sol−gel route. The systems were obtained by starting from ethanolic solutions of tetraethoxysilane (Si(OC2H5)4, TEOS) and copper(II) acetate (Cu(CH3COO)2·4H2O) in a single-step process and subsequently annealed ex situ under different atmospheres (air, nitrogen, or 4% H2 in N2 mixture). In particular, the attention was focused on the possibility of tailoring the system composition and microstructure through a proper choice of the treatment temperatures (100−900 °C), duration (1−5 h), and environment. The composite evolution under annealing was investigated by glancing incidence X-ray diffraction, optical absorption spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. Pure copper−silica-based nanosystems, with guest composition ranging from CuO to Cu and controllable particle size and distribution, were obtained. The stepwise formatio.