Miracle-dz/UniFAR-FTUs huggingface dataset:
Preparation of a novel metal-chelate affinity beads for albumin isolation from human plasma

In this study, we developed a novel approach to obtain a high protein-adsorption capacity utilizing 2-methacryloylamidohistidine (MAH) as a biollgand. MAH was synthesized by reacting methacryloyl chloride and histidine. Spherical beads, with an average size of 150–200 μm, were obtained by the radical suspension polymerization of MAH, ethyleneglycol dimethacrylate (EGDMA), and 2-hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. p(EGDMA–HEMA–MAH) beads had a specific surface area of 17.6 m2/g. The synthesized MAH monomer was characterized by NMR. p(EGDMA–HEMA–MAH) beads were characterized by a swelling test, FTIR, and elemental analysis. Then, Cu(II) ions were incorporated into the beads and Cu(II) loading was found to be 0.96 mmol/g. These beads, with a swelling ratio of 65% and containing 1.6 mmol MAH/g, were used in the adsorption/desorption of human serum albumin (HSA) from both aqueous solutions and human serum. The adsorption of HSA onto p(EGDMA–HEMA–MAH) was low (8.8 mg/g). Cu(II) chelation onto the beads significantly increased the HSA adsorption (56.3 mg/g). The maximum HSA adsorption was observed at pH 8.0 Higher HSA adsorption was observed from human serum (94.6 mg HSA/g). Adsorptions of other serum proteins were obtained as 3.7 mg/g for fibrinogen and 8.5 mg/g for γ-globulin. The total protein adsorption was determined as 107.1 mg/g. Desorption of HSA was obtained using a 0.1M Tris/HCI buffer containing 0.5M NaSCN. High desorption ratios (to 98% of the adsorbed HSA) were observed. It was possible to reuse Cu(II)-chelated p(EGDMA–HEMA–MAH) beads without significant decreases in the adsorption capacities. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2840–2847, 2003
GRAPHENE AS TUNABLE STATIONARY PHASE ADDITIVE FOR ENANTIOSEPARATION

Graphene-based biosensor and chiral sensor have made significant progress in recent years. Because of the similarity of the optical enantiomers, enantioseparation is perhaps the most subtle to achieve. Developing more effectively chiral separation techniques based on graphene is highly desirable. Herein, pristine graphene was prepared and then applicated to assist resolution of two racemic drugs of propranolol and ofloxacin using thin-layer chromatography (TLC). In comparison with TLC chiral separation by only using pure D-(-)-tartaric acid as a selector with relatively low degree of separation, a mixture of graphene and D-(-)-tartaric acid is more attractive, efficient and ready available. The high specific resolution ability for racemic compounds aided by graphene might allow its potential application in future chiral separation technologies.
A comparison between HPLC-dynamic reaction cell-ICP-MS and HPLC-sector field-ICP-MS for the detection of glutathione-trapped reactive drug metabolites using clozapine as a model compound

In this study, a novel method was developed for tracing down reactive drug metabolites, the formation of which in the human body constitutes an important health risk as a result of their capability to bind to body proteins and DNA. Clozapine was used as a model because this drug forms both reactive and stable metabolites. Glutathione, which forms complexes with reactive metabolites, was added in order to trap reactive species of clozapine, formed by degradation in an electrochemical cell, thereby mimicking the real drug metabolism process. The method developed is based on the use of reversed-phase HPLC as a chromatographic separation technique and inductively coupled plasma-mass spectrometry (ICP-MS) for monitoring of Cl and S. Via Cl-monitoring, all metabolites of the Cl-containing clozapine can be detected, whereas S-monitoring allows for the detection of the S-containing molecule glutathione and its conjugates with reactive metabolites. The spectral overlap of the signals of 32S+ and 34S+ with those of 16O16O+ and 16O18O+, respectively, was tackled in 2 ways. On one hand, a quadrupole-based ICP-MS instrument, equipped with a dynamic reaction cell, was used. O2 was used as a reaction gas to convert the S+ ions to a sufficient extent into the corresponding SO+ species. This did not yield optimal results, due to pronounced ArC+ signals at mass 48 and 50 upon introduction of methanol into the ICP. On the other hand, a sector-field ICP-MS instrument operated at medium mass resolution permitted interference-free monitoring of the S+-signals. A new type of skimmer cone – termed X-skimmer – was evaluated and its use resulted in a 4-fold increase in the sensitivity in a methanolic environment, providing a limit of detection of 1 μg L−1 for S. The chromatograms obtained via HPLC-SF-ICP-MS permitted differentiation between reactive and stable metabolites. As a result, the method developed looks very promising for the detection of glutathione conjugates and shows potential for their quantification in early stages of drug development when a radiolabeled compound is not yet available.
A critical assessment of methods for the intrinsic analysis of liquid interfaces: 2. Density profiles

Substantial improvements in the molecular level understanding of fluid interfaces have recently been achieved by recognizing the importance of detecting the intrinsic surface of the coexisting condensed phases in computer simulations (i.e., after the removal of corrugations caused by capillary waves) and by developing several methods for identifying the molecules that are indeed located at the boundary of the two phases. In our previous paper [J. Phys. Chem. C 2010, 114, 11169], we critically compared those methods in terms of reliability, robustness, and computation speed. Once the intrinsic surface of a given phase is detected, various profiles, such as the density profiles of the components, can be calculated relative to this intrinsic surface rather than to the macroscopically planar Gibbs dividing surface. As a continuation of our previous study, here we present a detailed and critical comparison of various methods that can be used to calculate intrinsic density profiles once the full set of truly interfacial molecules has been identified. Two of the methods, the Fourier function and the Voronoi tessellation, are already described in the literature; two other methods, the covering surface and the triangular interpolation, are newly proposed algorithms; one method, the modified grid-based intrinsic profile (GIP) method, is an improvement over an existing procedure. The different methods are again compared in terms of accuracy and computational cost. On the basis of this comparison, we propose a fast and accurate protocol to be routinely used for intrinsic surface analyses in computer simulations.
Atmospheric pressure glow discharge plasma in air at frequency 50 Hz

Homogeneous atmospheric pressure discharge using a dielectric barrier discharge in air at 50 Hz was investigated. Porous alumina ceramic sheets were used as a dielectric barrier. In this paper we compare the filamentary discharge initiated by using glass sheets as a dielectric and the glow discharge obtained by the porous alumina sheets as a dielectric. Generally, the discharge in a dielectric barrier arrangement consists of a large number of filaments. Using porous alumina sheets Al2O3, an atmospheric pressure glow discharge (APGD) plasma has been obtained. This APGD discharge is characterized by a homogeneous profile of long lifetime (∼5 ms) and the current is one pulse per half cycle of the power supply. The electrical measurements and the emission spectrum confirm that the discharge has been formed in the glow mode.
Proteins multi‐funnel energy landscape and misfolding diseases

The problem of how a given α-amino acid sequence, in cells, most of the times, assumes the native structure, is a fundamental problem in Biology, known as the protein folding problem. Here, evidence is presented that suggests that the same α-amino acid sequence can assume several, very different, structures that have the same Gibbs energy as the native structure, in the same thermodynamic conditions. These results lend support to a multi-funnel Gibbs energy landscape for proteins in which Anfinsen's thermodynamic hypothesis alone cannot explain protein folding. How then do proteins fold? In a multi-funnel picture, transient deterministic forces are needed to select the native funnel from all other funnels that the protein can potentially fall into. The suggestion here is that such transient, deterministic forces arise from specific vibrational excited states (VES) that constitute the first step in protein folding and function (the VES hypothesis). An application of the VES hypothesis to calculate the energy absorbed, from water molecules, by a protein α-helix with extensive glutamine (gln) repeats is made, which can explain the structural instability of these proteins and their association with many misfolding diseases. Copyright © 2008 John Wiley & Sons, Ltd.
Quantitative Studies on the Oxygen and Nitrogen Functionalization of Carbon Nanotubes Performed in the Gas Phase

Gas-phase methods were applied for the oxygen and nitrogen functionalization of multiwalled carbon nanotubes (CNTs). The oxygen functionalization was performed by HNO3 vapor treatment at temperatures from 200 to 250 °C for 12 h up to 120 h. The oxygen-functionalized CNTs were used as the starting material for nitrogen functionalization through thermal treatment under NH3. The BET surface area increased after the treatment in HNO3 vapor, which also caused the weight loss due to carbon corrosion. The oxygen content increased with increasing treatment time but decreased with increasing temperature, as disclosed by elemental analysis, X-ray photoelectron spectroscopy, and temperature-programmed desorption (TPD) results. The surface acidity increased with increasing treatment time as shown by TPD using NH3 as a probe molecule. As to nitrogen functionalization, the amount of nitrogen was correlated with the oxygen amount in the starting CNTs. A higher NH3 concentration caused a lower BET surface area due to car.
Rheological Determination of Interaction Potential Energy for Aqueous Clay Suspensions

Swelling clay suspensions, considered as strongly anisotropic disks, are very unstable in high shear flows. In this study of sodium montmorillonites from Wyoming and China, a hard sphere model is shown to be relevant for the rheological modeling of dilute solutions (2−20 g/L). For more concentrated systems (20−80 g/L), orientation and alignment effects seem to be preponderant. High shear measurements give complete information on the average clay size and critical percolation concentration necessary for the yield stress appearance. At low shear, when interaction effects are dominant, an electrostatic double-layer approach gives directly the average interaction pair potential, allowing good predictions of the elasticity and yield stress of clay dispersions.
A risk‐based protocol to develop acceptable concentrations of bioaccumulative organic chemicals in sediments for the protection of piscivorous wildlife

Abstract Environmental quality guidelines are benchmarks that indicate whether or not environmental concentrations present measureable risks to ecosystem health. This paper outlines an approach for the development of guidelines for concentrations of bioaccumulative organic chemicals in sediments that would be protective of wildlife at the top of the food chain an aquatic ecosystem. The proposed method uses risk assessment techniques that integrate information on relevant exposure pathways from sediments to top predators and toxicity assessment for avian and mammalian species. The method requires biota‐to‐sediment bioaccumulation factors (BSAFs) for various ecosystems and food webs and knowledge of the predator‐prey relationships and physiological parameters of piscivores. The proposed method is considered to be an improvement to existing regulatory methods for the derivation of water quality guidelines that are based on acute and chronic toxicity data generated primarily from waterborne exposure assays of.
Processing of low carbon content interstellar ice analogues by cosmic rays: implications for the chemistry around oxygen-rich stars

Radiolysis of a homogeneous H2O:H2CO:CH3OH (100:2:0.8) ice mixture by fast heavy ions is performed in the laboratory in an attempt to simulate the interaction of cosmic rays with frozen surfaces at 15 K. Bombarded by 220-MeV 16O7 + ions, the ice layer is thin enough to be traversed by projectiles at approximately constant velocity and with charge states close to the equilibrium one. Analysis by Fourier transform infrared spectroscopy (FTIR) reveals that the molecular species formed are CH4, CO2, CO, HCO, HCOO− and CH3OCHO. The formation and dissociation cross-sections of all observed daughter molecules are determined. As a control procedure, a carbon budget is performed as the beam fluence increases. The observed radiation effects lead to a general observation that the destruction cross-sections of condensed gases by heavy ions are ruled by a power law that is a function of the electronic stopping power: σ d ∼ S e , where n is approximately 3/2. This relation is observed for the destruction of precursor H2CO molecules and for the formation of daughter species. The present results help our understanding of the chemical and physicochemical interactions induced by heavy cosmic rays in cold astrophysical environments with low carbon contents, such as those around
Investigations of Secondary Organic Aerosol Formation in Laboratory Chambers

Secondary organic aerosol (SOA) is produced in the atmosphere by oxidation of volatile organic compounds. Laboratory chambers are used understand the formation mechanisms and evolution of SOA formed under controlled conditions. This thesis presents studies of SOA formed from anthropogenic and biogenic precursors and discusses the effects of chamber walls on suspended vapors and particles. During a chamber experiment, suspended vapors and particles can interact with the chamber walls. Particle wall loss is relatively well-understood, but vapor wall losses have received little study. Vapor wall loss of 2,3-epoxy-1,4-butanediol (BEPOX) and glyoxal was identified, quantified, and found to depend on chamber age and relative humidity. Particles reside in the atmosphere for a week or more and can evolve chemically during that time period, a process termed aging. Simulating aging in laboratory chambers has proven to be challenging. A protocol was developed to extend the duration of a chamber experiment to 36 h of oxidation and was used to evaluate aging of SOA produced from m-xylene. Total SOA mass concentration increased and then decreased with increasing photooxidation suggesting a transition from functionalization to fragmentation chemistry driven by photochemical processes. SOA oxidation, measured as the bulk particle elemental oxygen-to-carbon ratio and fraction of organic mass at m/z 44, increased continuously starting after 5 h of photooxidation. The physical state and chemical composition of an organic aerosol affect the mixing of aerosol components and its interactions with condensing species. A laboratory chamber protocol was developed to evaluate the mixing of SOA produced sequentially from two different sources by heating the chamber to induce particle evaporation. Using this protocol, SOA produced from toluene was found to be less volatile than that produced from a-pinene. When the two types of SOA were formed sequentially, the evaporation behavior most closely represented that of SOA from the second parent hydrocarbon, suggesting that the structure of the mixed SOA particles resembles a core of SOA from the first precursor coated by a layer of SOA from the second precursor, indicative of limiting mixing.
Adsorption of arsenate from aqueous solution by rice husk-based adsorbent

Rice husk-based adsorbent (RHBA) was prepared by burning rice husk in a muffle furnace at 400°C for 4 h and adsorption of arsenate by the RHBA from aqueous solution was examined. Batch adsorption test showed that extent of arsenate adsorption depended on contact time and pH. Equilibrium adsorption was attained in 60 min, with maximum adsorption occurring at pH 7. Equilibrium adsorption data were well described by the Freundlich isotherm model. Freundlich constants Kf and 1/n were 3.62 and 2, respectively. The RHBA is effective in the adsorption of arsenate from water and is a potentially suitable filter medium for removing arsenate from groundwater at wells or in households.
Greatly reduced leakage current in BiFeO3 thin film by oxygen ion implantation

Oxygen ions are implanted into BiFeO3 films on LaNiO3/SrTiO3(1 0 0) substrates. The evolution of films is characterized by x-ray diffraction, scanning electron microscopy and cross-sectional transmission electron microscopy. The leakage current density of the implanted films is lowered by two orders of magnitude in comparison with unimplanted BFO films. The mechanisms for reduced leakage current in BiFeO3 thin films are discussed.
Simple, Rapid, and Sensitive Spectrofluorimetric Determination of Zaleplon in Micellar Medium

Abstract The influence of micellar medium on the absorption, fluorescent excitation and emission spectra character of Zaleplon was studied. The nonionic surfactant of Triton X-100 showed a strong sensitizing effect for the fluorescence of Zaleplon in a pH 5.0 buffer. The possible enhancement mechanism was discussed. Based on the optimum conditions, a simple, rapid, sensitive and selective spectrofluorimetric method (λex/λem = 345/455 nm) has been developed for the determination of Zaleplon. The linear range was 1.32 × 10−8–1.00 × 10−5 mol/L. The detection limit was 4.0 × 10−9 mol/L with an RSD of 0.06%. The proposed method was successfully applied to the determination of Zaleplon in tablets, serum and urine.
Engineering of Chemical Complexity

Oscillatory Behavior in Cellular Regulatory Networks Chemically-Driven Biological Brownian Machines Modeling Substrate-Based Motility of Eukaryotic Cells Stimuli-Induced Reconfiguration and Directed Motion of Responsive Gels From Colloid Thermophoresis to Thermophoretic Machines Collective Motions in Populations of Microdroplets Dissipative Patterns in Systems of Coupled Reactive Nano- and Microdroplets Dynamics of Filaments of Scroll Waves Control of Chemical Wave Propagation Synchronization Phenomena during Elecrodissolution of Silicon and other papers
Super-linear frequency dependence of ac conductivity of disordered Ag2S–Sb2S3 at cryogenic temperatures

The ac conductivity of a new class of disordered solids, i.e. mechanochemically synthesized amorphous fast ion conducting Ag2S–Sb2S3 materials, has been investigated in the audio frequency range (10–107 Hz) down to cryogenic temperatures (∼10 K). The conductivity spectra exhibit the usual signature of a disordered system at higher temperatures, well described by the Jonscher power law (JPL) i.e., σ′(ω) = σ dc + A(T)ω*, although the frequency exponent (n < 1) is found to be a weak function of temperature. However, as the temperature is lowered, the frequency width of the σ dc region decreases gradually and that of the JPL region increases. Eventually, the σ dc region disappears and the JPL region alone dominates the spectrum. However, at the lowest temperatures, both the σ dc and JPL regions disappear and σ′(ω) obeys a super-linear power law (SPL) (σ′ ∝ ωm , m ≥ 1). It is observed that the SPL has strikingly similar characteristics to the well-established nearly-constant-loss (NCL) behaviour corresponding to m = 1. Both SPL and NCL appear in the same time–temperature (low-temperature/low-frequency) domain. Furthermore, in both cases the conductivity is a distinctly weak function of temperature but quite sensitive to frequency, and the SPL/NCL → JPL crossover frequency is thermally activated with almost the same energy as the ac activation energy. The presence of the SPL is further manifested in the form of a well-defined minimum in the dielectric loss, ε″(ω), spectra. It is therefore proposed that the entire low-temperature/low-frequency spectra can be described by a modified Jonscher power law, σ′(ω) = σ dc(T) + A(T) ωn + B(T)ωm , m = 1 (NCL), m > 1 (SPL), where the second term with n < 1 accounts for the JPL and the third term with m ≥ 1 accounts for SPL/NCL. The results and some other low-temperature/low-frequency conductivity data are consistent with an asymmetric double well potential (ADWP) model.
Cognitive, Affective, Social and Cultural Aspects of Teaching and Learning in Media Studies

The vision that we will present is not intended to be exhaustive or totalizing, although it does attempt to highlight the most significant aspects that characterize it. It is a reflection of more than twenty years of work in the educational field, at different levels and with different functions, it is also the result of personal evolution, and how she will be subject to evolution. Comparing media studies with the 19th century, it seems that media has conquered an essential position in every individual's life. This study meets the requirements of a growing pool of traditional and non-traditional students, including teachers, who find education as an important aspect for jobs in the modern age of information and technology. This research will utilize the literature which has been published already, including quantitative as well as qualitative measures. Past papers were selected, which were published in different areas. Comparing with other empirical research, the first phase of the procedure of the study is to collect the data The study is to identify the teachers and learner's characteristics such as affective, cognitive, and social factors which causes an impact on learning and teaching enhanced environment in media studies.
Rayleigh scattering in multilayered structures of porous silicon

The possibility of growing high-quality porous silicon (por-Si) multilayered structures[1,2], which can consist of hundreds of layers with different, controllable porosity [3], revealed variousnew ways of using this material in optoelectronics and photonics. Apart from obvious applications of por-Si multilayered structures as mirrors, optical ﬁlters, etc., the most attractive goal is to combine the photonicmanipulation with the por-Si luminescence, which, in principle, would allow the fabrication of Si-basedlasers with adjustable properties [4]. The photon transport through the por-Si multilayered structure is usually described using the transfermatrix method [5]. In this approximation it is assumed that the individual por-Si layers can be characterizedby a well deﬁned refractive index, which depends on porosity. The general features of the reﬂection andtransmission coefﬁcients are reproduced by this method (see, e.g., the recent observation of the photonicBloch oscillations [6]). However, even in the case when the absorption is negligible, not all interferencepeaks predicted by the transfer matrix calculations are seen experimentally, and the observed peaks arenoticeable suppressed [6,7]. To get more insight in this phenomenon it is convenient to study some simplemultilayered structures, in particular those containing a single microcavity, where the resonant transmit-tance peak is well separated and could be analyzed in details. Below we present the experimental data onthe transmittance spectra of several structures of this sort. The observed suppression of the resonant peaksis then interpreted by taking into account the Rayleigh scattering of light on the microscopic structuredisorder of por-Si—the effect, which is not allowed for in the transfer matrix calculations.