Miracle-dz/UniFAR-FTUs huggingface dataset:
HPLC/DAD Assay of Related Impurity Ethyl-4-oxopiperidine-1-carboxylate in Loratadine Through Derivatization with 2,4-Dinitrophenylhydrazine

Abstract Assay of ethyl-4-oxopiperidine-1-carboxylate (Impurity H) as related impurity in loratadine (active ingredient or in its pharmaceutical formulations) has been achieved through precolumn derivatization with 2,4-dinitrophenylhydrazine followed by HPLC/DAD. The derivatization reaction was found to be selective, fast, quantitative, and allows good sensitivity when monitored at 368 nm detection wavelength (absolute limit of quantitation is placed around 0.1 µg/mL, meaning 0.01% with respect to the amount of loratadine used in the test solution and 1/10 from the maximum allowed threshold for impurity H). Derivatization conditions and kinetics of the reaction are discussed. For convenience, the HPLC method used for separation of the derivatization product is identical to the method described in the European Pharmacopoeia 6.0, loratadine monograph, the test for related substances (other than impurity H). No interferences from the other compendial cited impurities of loratadine and from the derivatization reagent or related byproducts were observed. The assay was validated according to guidances in force. A linear response function was obtained over the concentration interval 0.1 to 8 µg/mL (0.01 to 0.8% impurity H in loratadine). The precision of the method against the derivatization product is characterized by a relative standard deviation of peak areas below 5%. The accuracy of the method is placed in the 95–105% interval (expressed as % bias from the theoretical concentration values). Stress studies were applied on loratadine to demonstrate that impurity H may represent a degradation byproduct. The method can be easily applied and may successfully replace the gas chromatographic/flame ionization detection (GC-FID) method designed for impurity H in the compendial EP monograph.
The effects of external electric field on the electron transport system of spinach chloroplasts

Since the thylakoid membranes of an active chloroplast are constantly exposed to the electric fields generated by the electron transport system inside the membranes, we have studied the effects of pretreating chloroplasts of spinach (Spinacia oleracea L.) leaves with an external AC (alternating current) electric field on their electron transport system. It was found that a few minutes electric field pretreatment (333 V cm-1 across chloroplast samples), especially at low frequency, irreversibly inhibited the activity of photosystem II (PSII), but under certain conditions, stimulated that of photosystem I (PSI). From the measurements of fluorescence from PSII, we ascribe the inhibition to a lesion close to its reaction center P680, leading to increased dissipation of excitation energy to heat. The effect on PSI was investigated by the reduction of its reaction center, P700 by various artificial donors. We suggest that the stimulative effect can be attributed to a positive shift of the surface charge density of thylakoid membranes that brings about an increase in the accessibility of exogenous electronegative donors.
Thermal model of Knudsen cells for organic molecular beam deposition

Knudsen cells used for molecular beam deposition of organic materials are usually derived from the ones employed for conventional epitaxy of inorganic semiconductors. However, organic molecular materials need rather low evaporation temperatures and a very precise temperature control in the range from 100 to 400 °C. Therefore, a thermal model of the cell is needed, which, taking into account the peculiarity of organic molecular beam deposition, gives the thermal dynamics of the cell and can be used for developing accurate algorithms for thermal programming and control. In this article such a model is developed and fully assessed through a comparison with experimental results; on this basis, all information necessary for precisely controlling and programming Knudsen cells for organics is obtained.
Enzymatic reaction model for the production of symmetrical lipid molecules using the response surface methodology

초콜릿은 코코아 버터(Cocoa butter, CB)를 주원료로 하여 코코아 매스와 당류를 함께 적절히 배 합하여 만든 가공식품으로 정의한다. 코코아 버터는 덥고 습한 열대우림 지역에서 자라는 벽오동과 목본식물 카카오(Theobroma cacao)의 종자에서 얻을 수 있다(Liendoa et al., 1997). 코코아 버터 는 실온에서 굳은 상태로 존재하고 부러지기 쉬우나 체온에서는 급속히 녹는 예민한 융점을 갖는다. 이러한 특징은 코코아버터를 구성하는 triacylglycerol (TAG)의 지방산 조성이 palmitic acid 25 30%, stearic acid 31 37%, 그리고 oleic acid 31 38%의 단순한 지방산 조성으로 이루어져 있고 (Spangenberg, 2001), TAG를 구성하는 지방산의 분포가 포화-불포화-포화(Saturated–Unsaturated– OPEN ACCESS
Antifungal secoabietane dialdehyde and bisabolane-type terpenoids from the heartwood of Cryptomeria japonica D. Don

‘‘Sugi’’ or Japanese cedar (Cryptomeria japonica D. Don, Taxodiaceae) is a high quality wood commonly utilized as a building material (Hon and Minemura 1991). A large number of phytochemicals from leaves, wood and bark of Sugi have been reported, including sesquiterpenes, diterpenes, triterpenes and norlignans-related compounds (Su et al. 1993; Chen et al. 2001; Morisawa et al. 2002; Yoshikawa et al. 2006). From the same species, Arihara et al. (2004) have isolated norlignans, sesquiterpenes and abietane diterpenes, and the dimers, including a positive diastereomer of 12-hydroxy-6,7-secoabieta8,11,13-triene-6,7-dial. As a continuation of our research about biologically active compounds, here we report the isolation, identification and antifungal activity of the negative diastereomer of 12-hydroxy-6,7-secoabieta8,11,13-triene-6,7-dial and a known bisabolane-type sesquiterpene from the heartwood of sugi.
2-Oxoindolin-3-ylidene Derivatives as 2π Components in 1,3-Dipolar Cycloadditions of Azomethine Ylides

Abstract The 1,3-dipolar cycloadditions of various azomethine ylides to 2-oxoindolin-3-ylidene derivatives have been investigated. The structure and stereochemistry of cycloadducts were studied in detail by NMR spectroscopic methods.
Formation of Ordered Mesoporous MgO with Tunable Pore Diameter and Its Application As Excellent Alkaline Catalyst in Baeyer−Villiger Oxidation

Highly ordered mesoporous MgO catalysts with tunable pore size distribution and fairly good alkaline property were successfully obtained by a double replication procedure. Small-angle XRD, TEM, and nitrogen adsorption and desorption results show that these mesoporous MgO materials possess a highly ordered 2D hexagonal mesostructure with tunable pore diameter that is obtained using different hydrothermal temperature derived SBA-15 and CNK-3 carbon as templates. The alkaline density was determined for all samples from the technique of temperature-programmed desorption of CO2 and FT-IR, and the mesoporous MgO with large pore diameter shows more basic sites than the reference bulk one. Such mesoporous MgO materials have been successfully used as base catalysts in the Baeyer−Villiger oxidation of cyclic ketones to the corresponding lactones. 100% adamantanone conversion and >99% lactone selectivity were obtained over mesoporous MgO-373. The pore diameter has slight influence on the conversion of ketones, since.
Protein Bars and Packaging: A Sequential Explanatory Research to investigate the impact of packaging on consumer perceptions and intention to purchase in Ireland.

Background: There has been an increasing demand for protein bars in the European markets over the past decade which arises a need for companies to focus and create rightful package for their products as most of these brands offer similar value to the consumers in the market; and packaging is the only way by which these companies can differentiate their products in the retail environment. Purpose: The purpose of this paper is to explore the perceptions of consumers from different cultural backgrounds towards packaging of protein bars. It mainly emphasizes on developing an understanding of how specific cultural groups assess a protein bar; providing insights into their purchase patterns and shopping behaviors in the retail store and most importantly identifying the factors that influence their purchase decisions. Methodology: A Sequential Explanatory Research design combining both quantitative and qualitative methods was used to investigate the impact of packaging on consumers from different cultural backgrounds (Europeans, Asians, and Africans) and genders. The data for the quantitative analysis in the first phase was collected from 236 respondents through a structured survey; The SPSS software and R studio were used for statistical analysis. 30 interviews with consumers from different cultural backgrounds were conducted in the second phase for the qualitative analysis. The views of the respondents were interpreted through thematic coding. Triangulations of the results are presented for cross verification. Findings: The findings of this research through both methods reveal that there are significant differences between the perceptions of consumers from different ethnic backgrounds. It is observed that consumer purchase decisions are highly influenced by one particular attribute such as the nutritional benefits derived; the price attribute or the flavor when they intend etc to purchase a protein bar.
DENSITY FUNCTIONAL THEORY-BASED MOLECULAR DYNAMICS SIMULATION OF ACID-CATALYZED CHEMICAL REACTIONS IN LIQUID TRIOXANE

Ab initio molecular dynamics simulation is used to investigate the kinetics and thermodynamics of some of the chemical reactions that occur during the induction phase of acid-catalyzed polymerization of 1,3,5-trioxane. In particular, the first ab initio calculation of a free-energy profile in a condensed-phase system is presented. The introduction of an H+ ion to a sample of trioxane liquid initiates the complete protolysis of several trioxane molecules in a rapid succession of picoseconds. Subsequently, the re-formation of small formaldehyde oligomers is observed, which break up again after 1−2 ps. The fast kinetics is found to be consistent with the results of a constrained ab initio molecular dynamics evaluation of the free-energy profile for the formation of a protonated dimer. In the trioxane−formaldehyde mixture, this reaction is found to be barrierless with a reaction free energy in the thermal range (10 kJ mol-1). Solvation of the chemically active carbocation by formaldehyde molecules reduces the.
Controlling Surface Morphology of Electrospun Polystyrene Fibers: Effect of Humidity and Molecular Weight in the Electrospinning Process

Electrospinning is a technique used to produce micron to submicron diameter polymeric fibers. The surface of electrospun fibers is important when considering end-use applications. For example, the ability to introduce porous surface features of a known size is required if nanoparticles need to be deposited on the surface of the fiber or if drug molecules are to be incorporated for controlled release. Surface features, or pores, became evident when electrospinning in an atmosphere with more than 30% relative humidity. Increasing humidity causes an increase in the number, diameter, shape, and distribution of the pores. Increasing the molecular weight of the polystyrene (PS) results in larger, less uniform shaped pores. This work includes an investigation of how humidity and molecular weight affect the surface of electrospun PS fibers. The results of varying the humidity and molecular weight on the surface of electrospun PS fibers were studied using optical microscopy, field emission scanning electron micros.
A Neural Mass Model for Phase Amplitude Coupling in EEG

B) Modulation (Pf) of the output of the sigmoid block represents the influence of background noise activity on expected firing rate of fast inhibitory population Neural Mass Models are mesoscopic models used to describe and reproduce key properties of the EEG. A property relevant to control functions in the brain such as selective attention, working memory, etc. is PhaseAmplitude Coupling. We aim to develop a Neural Mass Model that incorporates PAC. Introduction
Super-Resolved Raman Spectroscopy

ABSTRACT In this paper we present a super-resolved Raman spectroscopy configuration where, due to the proposed resolution improvement, more chemical species can be simultaneously detected. The idea includes usage of the basic property of Raman in which shifting the excitation wavelength will shift the absolute wavelength of the Raman spectral lines. Thus, encoding the spectra prior to analysis by the spectrometer allows obtaining spectral super-resolved sensing via time multiplexing super-resolution concepts applied over the spectral domain.
Pyrotechnic Countermeasures. III: The Influence of Oxygen Balance of an Aromatic Fuel on the Color Ratio of Spectral Flare Compositions

The influence of the oxygen balance, L, of an anthracene-type aromatic fuel in flare compositions on the spectral color ratio, that is the ratio of radiation emitted in band A (l ¼ 1.8 – 2.5 mm) versus radiation emitted in band B (l ¼ 3.5 – 4.8 mm), is investigated. Eight compositions based on potassium perchlorate, polychloroprene binder and either of the following fuels, anthracene, C14H10 (1), anthracene-d 10 ,C 14D10 (2), phenanthrene C14H10 (3), anthrone, C14H10 O( 4), anthraquinone, C14H8O2 (5), 1-aminoanthraquinone, C14H9NO2 (6), 1,5-dihydroxyanthraquinone, C14H8O4 (7) and 1,5dinitroanthraquinone, C14H6N2O6 (8) were prepared and radiometrically investigated. The highest spectral efficiency, El in A-band is obtained with the phenanthrene based composition D3. This mixture also displays the lowest spectral color ratio, qA/B. The highest color ratio is obtained with 1,5-dihydroxyanthraquinone as fuel. The burn rate is highest with anthracene and decreases steadily with increasing oxygen balance of the fuel. The thermodynamic equilibrium compositions, combustion temperatures and spectral efficiencies are given. For part II see Ref. [3].
Additions and corrections: stereochemistry of allyl sulfones. on the structure of metalated allyl sulfones and their stereochemistry of alkylation.

Nucleophilic Activation of Coordinated Carbon Monoxide. 3. Hydroxide and Methoxide Reactions with the Trinuclear Clusters MJ(C0)12 ( M = Fe, Ru or Os). Implications with Regard to Catalysis of the Water Cas Shift Reaction [J. Am. Chem. SOC. 1985, 107, 585-5933. DAVID C. GROSS and PETER C. FORD* Page 592: The two equations appearing in the right-side column of print are incorrect. These should be respectively
X-ray angiography using kinetic imaging: optimising image signal-to-noise ratio

Poster: "ECR 2018 / C-2368 / X-ray angiography using kinetic imaging: optimising image signal-to-noise ratio" by: "I. Gog, M. Gyano, V. I. Orias, Z. Ruzsa, B. Nemes, B. Merkely, K. Szigeti, S. Osvath, P. Sotonyi; Budapest/HU"
Nucleation and Growth of Hydrates on Ice Surfaces: New Insights from 129Xe NMR Experiments with Hyperpolarized Xenon

The nucleation and growth of hydrate on the surface of ice was followed by NMR spectroscopy using hyperpolarized Xe. From the ice surface area and Xe pressure drop, the thickness of the hydrate film formed was ∼ 500−1000 A before the reaction became extremely slow. The cage occupancy ratio θL/θS was measured as a function of time from the Xe spectrum and was used to monitor the nature of the material formed. The ratio changed from values close to 1 during the early part of the reaction (induction time) to its equilibrium value of ∼3−4 after nucleation processes were finished and rapid growth commenced. The low value can be seen as evidence of a precursor phase that is quite different from the equilibrium hydrate. The induction time was found to be a reproducible function of temperature and pressure for the conditions studied. The kinetics of gas uptake was analyzed according to the Avrami−Erofeyev equation used to describe solid−gas reactions. A surface memory effect was noted on successive cycles of xeno.
Fractionated extraction of polycyclic aromatic hydrocarbons (PAHs) from polluted soils: estimation of the PAH fraction degradable through bioremediation

Chemical extractions were tested to estimate the fraction of 15 polycyclic aromatic hydrocarbons (PAHs) in polluted soils degradable through bioremediation. Of 30 soil samples, differing in PAH concentrations, from 10 long‐term polluted sites, four were used in screening tests conducted with 14 different extractants. PAH extractability increased in the order salt solutions < surfactant solutions < organic solvents and organic solvent–water mixtures. Closest correlations (r = 0.73–0.91) and ratios of c. 1:1 of the extracted to the degradable PAH concentrations were found with aqueous solutions of two surfactants (Genapol UDD 88, Synperonic LF/RA 30).
Cumulant-based expressions for the multibody terms for the correlation between local and electrostatic interactions in the united-residue force field

A general method to derive site-site or united-residue potentials is presented. The basic principle of the method is the separation of the degrees of freedom of a system into the primary and secondary ones. The primary degrees of freedom describe the basic features of the system, while the secondary ones are averaged over when calculating the potential of mean force, which is hereafter referred to as the restricted free energy (RFE) function. The RFE can be factored into one-, two-, and multibody terms, using the cluster-cumulant expansion of Kubo. These factors can be assigned the functional forms of the corresponding lowest-order nonzero generalized cumulants, which can, in most cases, be evaluated analytically, after making some simplifying assumptions. This procedure to derive coarse-grain force fields is very valuable when applied to multibody terms, whose functional forms are hard to deduce in another way (e.g., from structural databases). After the functional forms have been derived, they can be parametrized based on the RFE surfaces of model systems obtained from all-atom models or on the statistics derived from structural databases. The approach has been applied to our united-residue force field for proteins. Analytical expressions were derived for the multibody terms pertaining to the correlation between local and electrostatic interactions within the polypeptide backbone; these expressions correspond to up to sixth-order terms in the cumulant expansion of the RFE. These expressions were subsequently parametrized by fitting to the RFEs of selected peptide fragments, calculated with the empirical conformational energy program for peptides force field. The new multibody terms enable not only the heretofore predictable α-helical segments, but also regular β-sheets, to form as the lowest-energy structures, as assessed by test calculations on a model helical protein A, as well as a model 20-residue polypeptide (betanova); the latter was not possible without introducing these new terms.
Theoretical simulations on photoexcitation dynamics of the silver atom embedded in helium clusters

Quantum molecular dynamics simulations have been performed to study the photoexcitation Ag(5p 2PJ)←Ag(5s 2S1/2) in size-selected helium clusters considering electronically nonadiabatic transitions. We employed the hybrid method in which the electronic degree of freedom of Ag(2P) was treated quantum mechanically while the motions of helium atoms were described by the semiclassical path integral centroid molecular dynamics method in order to take the quantum fluctuation effect into account. It has been found that the dynamics after photoexcitation is dominantly nonadiabatic in all cluster sizes studied, and that nonadiabatic transitions are enhanced by quantum fluctuation of helium motions. Most of the photoexcited AgHen clusters decompose into an isolated Ag atom and free helium atoms within several picoseconds. However, Ag*Hen (n=1–5) exciplex formation was also found to occur for all helium cluster sizes studied, although this process is found to be minor.
Regression Statistics in Discriminant Analysis

fall on the correct side of the threshold at 0.5 or not. of course it would be nice if all the zeros were predicted as very close to zero and all the ones as very close to one, but a successful classification rule does not require such perfection. Note also that it is perfectly possible to have negative predictions for y. Indeed about half of the group A predictions would be expected to be negative. It is useful to add the horizontal line at 0.5, as has been done in Figure 1, if the software permits.
On the shear modulus of the flux line lattice

The shear modulus c66 of the flux line lattice in type II superconductors can be obtained from a two-body interaction between the flux lines even a t large inductions B ≈Hc2. The potential is composed of a repulsive and an attractive part and has a range diverging at Hc2. An explicit expression for the Ginsburg-Landau c66 is given for arbitrary B and x. From Gorkov's microscopic theory c66 is derived for large B and arbitrary temperature. Simple approximate formula are given. Der Schubmodul des Flusliniengitters in Supraleitern zweiter Art kann aus einer Zweikorperwechselwirkung zwischen den Fluslinien erklart werden, auch bei hoher Induktion B ≈ Hc2. Das Potential setzt sich aus einem abstosenden und einem anziehenden Anteil zusammen. Seine Reichweite divergiert bei Hc2. Ein expliziter Ausdruck fur das c66 der Ginsburg-Landau-Theorie wird fur beliebige B und x angegeben. Aus Gorskovs mikroskopischer Theorie wird c66 fur grose B und beliebige Temperaturen hergeleitet. Einfache Naherungsformeln werden angegeben.
Using fractal analysis of thermal signatures for thyroid disease evaluation

The skin is the largest organ of the body and it protects against heat, light, injury and infection. Skin temperature is an important parameter for diagnosing diseases. Thermal analysis is non-invasive, painless, and relatively inexpensive, showing a great potential research. Since the thyroid regulates metabolic rate it is intimately connected to body temperature, more than, any modification of its function generates a specific thermal image on the neck skin. The shapes of thermal signatures are often irregular in size and shape. Euclidean geometry is not able to evaluate their shape for different thyroid diseases, and fractal geometry is used in this paper. Different thyroid diseases generate different shapes, and their complexity are evaluated by specific mathematical approaches, fractal analysis, in order to the evaluate selfsimilarity and lacunarity. Two kinds of thyroid diseases, hyperthyroidism and papillary cancer are analyzed in this paper. The results are encouraging and show the ability to continue research for thermal signature to be used in early diagnosis of thyroid diseases.
Virial equation of state for rigid spherocylinders

Third, fourth and fifth virial coefficients are reported for isotropic systems of hard prolate spherocylinders with length to breadth ratios of up to 6:1. The results are compared with other recent data for such molecules and with the predictions of an analytical equation of state for convex hard molecules. The variation with shape of the fourth virial coefficient suggested the possibility of negative values for very elongated molecules, and this was confirmed for a length-to-breadth ratio of 11:1. Pade approximants for the equation of state were found to give results in excellent agreement with Monte Carlo simulation data.
First-principles study of calcium di-silicide under high pressure

Electronic states for two possible high-pressure phases (with the structure and with the structure) of are determined by means of a local density approximation band-structure calculation. We confirm that these polymorphs can be regarded as doped networks of Si. However, a simple picture in terms of -orbitals is not adequate for explaining the conduction bands, because (i) an s-like band, which is anti-bonding in connections but bonding between segments of the network, appears and (ii) there is hybridization between Si and Ca.