Journal articles: 'Compound K-distribution'

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Koutras, Markos V., and Serkan Eryilmaz. "Compound Geometric Distribution of Order k." Methodology and Computing in Applied Probability 19, no. 2 (February 4, 2016): 377–93. http://dx.doi.org/10.1007/s11009-016-9482-y.

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Lee, Sang-Hyeok, Sangjin Ahn, and Mi-hyun Kim. "Comparing a Query Compound with Drug Target Classes Using 3D-Chemical Similarity." International Journal of Molecular Sciences 21, no. 12 (June 12, 2020): 4208. http://dx.doi.org/10.3390/ijms21124208.

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3D similarity is useful in predicting the profiles of unprecedented molecular frameworks that are 2D dissimilar to known compounds. When comparing pairs of compounds, 3D similarity of the pairs depends on conformational sampling, the alignment method, the chosen descriptors, and the similarity coefficients. In addition to these four factors, 3D chemocentric target prediction of an unknown compound requires compound–target associations, which replace compound-to-compound comparisons with compound-to-target comparisons. In this study, quantitative comparison of query compounds to target classes (one-to-group) was achieved via two types of 3D similarity distributions for the respective target class with parameter optimization for the fitting models: (1) maximum likelihood (ML) estimation of queries, and (2) the Gaussian mixture model (GMM) of target classes. While Jaccard–Tanimoto similarity of query-to-ligand pairs with 3D structures (sampled multi-conformers) can be transformed into query distribution using ML estimation, the ligand pair similarity within each target class can be transformed into a representative distribution of a target class through GMM, which is hyperparameterized via the expectation–maximization (EM) algorithm. To quantify the discriminativeness of a query ligand against target classes, the Kullback–Leibler (K–L) divergence of each query was calculated and compared between targets. 3D similarity-based K–L divergence together with the probability and the feasibility index, (Fm), showed discriminative power with regard to some query–class associations. The K–L divergence of 3D similarity distributions can be an additional method for (1) the rank of the 3D similarity score or (2) the p-value of one 3D similarity distribution to predict the target of unprecedented drug scaffolds.

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MÅNSSON, MARIANNE. "On Compound Poisson Approximation for Sequence Matching." Combinatorics, Probability and Computing 9, no. 6 (November 2000): 529–48. http://dx.doi.org/10.1017/s096354830000448x.

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Consider sequences {Xi}mi=1 and {Yj}nj=1 of independent random variables, taking values in a finite alphabet, and assume that the variables X1, X2, … and Y1, Y2, … follow the distributions μ and v, respectively. Two variables Xi and Yj are said to match if Xi = Yj. Let the number of matching subsequences of length k between the two sequences, when r, 0 [les ] r < k, mismatches are allowed, be denoted by W.In this paper we use Stein's method to bound the total variation distance between the distribution of W and a suitably chosen compound Poisson distribution. To derive rates of convergence, the case where E[W] stays bounded away from infinity, and the case where E[W] → ∞ as m, n → ∞, have to be treated separately. Under the assumption that ln n/ln(mn) → ρ ∈ (0, 1), we give conditions on the rate at which k → ∞, and on the distributions μ and v, for which the variation distance tends to zero.

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Gómez-Déniz, Emilio, and Luis Gómez. "The Rayleigh Birnbaum Saunders Distribution: A General Fading Model." Symmetry 12, no. 3 (March 3, 2020): 389. http://dx.doi.org/10.3390/sym12030389.

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A new compound non-symmetric distribution for modeling arbitrary fading-shadowing wireless channels is introduced and studied here. This distribution has some advantages in front of other well-known non-symmetric fading distributions such as the Rayleigh–lognormal distribution and the K distribution especially in the tails. We give closed-form expressions for the average BER of DPSK and MSK when the new distribution is used. Applications to compare how the new distribution works in comparisons with the Rayleigh–lognormal, K distributions and others recently proposed in the literature of fading channel are also provided.

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Jeon, Ji-Hyeon, Bitna Kang, Sowon Lee, Sojeong Jin, Min-Koo Choi, and Im-Sook Song. "Pharmacokinetics and Intestinal Metabolism of Compound K in Rats and Mice." Pharmaceutics 12, no. 2 (February 3, 2020): 129. http://dx.doi.org/10.3390/pharmaceutics12020129.

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We aimed to investigate the plasma concentration, tissue distribution, and elimination of compound K following the intravenous administration of compound K (2 mg/kg) in rats and mice. The plasma concentrations of compound K in mice were much higher (about five-fold) than those in rats. In both rats and mice, compound K was mainly distributed in the liver and underwent biliary excretion. There was 28.4% fecal recovery of compound K in mice and 13.8% in rats, whereas its renal recovery was less than 0.1% in both rats and mice. Relative quantification of compound K and its metabolite protopanaxadiol (PPD) in rat bile and intestinal feces indicated that the metabolism from compound K into PPD occurred in the intestine but not in the plasma. Therefore, PPD detected in the plasma samples could have been absorbed from the intestine after metabolism in control rats, while PPD could not be detected in the plasma samples from bile duct cannulated rats. In conclusion, mice and rats shared common features such as exclusive liver distribution, major excretion pathway via biliary route, and intestinal metabolism to PPD. However, there were significant differences between rats and mice in the plasma concentrations of compound K and the fecal recovery of compound K and PPD.

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Jamei, Saeed, Adi Maimun, Rasul Niazmand Bilandi, Nor Azwadi, Simone Mancini, Luigi Vitiello, and Maria De Carlini. "Wake behind a Compound Wing in Ground Effect." Journal of Marine Science and Engineering 8, no. 3 (March 1, 2020): 156. http://dx.doi.org/10.3390/jmse8030156.

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Flow structure is a crucial point for the conceptual design of Wing-in-Ground effect (WIG) crafts. In this study, pressure distributions around a compound wing, velocity and the turbulent intensity distribution in the wake area after trailing of the wing, have been investigated numerically. Computational simulations were completed regarding various angles of attack in-ground-effect. Two parts made up the compound wing: The first composed by one rectangular wing in the center, the second composed by a reverse taper wing, consisting of an anhedral angle at the side. A realizable k-ε turbulent model exhibited the flow field in the physical domain about the wing surface. The numerical results of the compound wing were validated using the data provided by wind tunnel tests. The flow structures around the compound wing were compared with that of a rectangular wing for different conditions. It was found that the pressure distribution on the rectangular wing was weaker than at the lower surface for the compound wing. However, the suction effect on the upper surface of the rectangular wing was higher. Also, the velocity defect and the turbulence level in the wake area was greater behind the compound wing.

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Fardhyanti, Dewi Selvia, Achmad Chafidz, Bayu Triwibowo, Haniif Prasetiawan, Novia Noor Cahyani, and Sinta Andriyani. "Improving the Quality of Bio-Oil Produced from Rice Husk Pyrolysis by Extraction of its Phenolic Compounds." Jurnal Bahan Alam Terbarukan 8, no. 2 (December 17, 2020): 90–100. http://dx.doi.org/10.15294/jbat.v8i2.22530.

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Rice husk is an agricultural waste which contains 50% cellulose, 25%-30% lignin and 15%-20% silica. It can be used as raw material of bio-oil. Bio-oil is liquid which produced by pyrolysis process. Bio-oil can be produced from the rice husk at 773 and 873 K. The main component of Bio-oil from rice husk pyrolysis at 773 and 873 K is phenolic compounds about 47.98% and 62.65%, respectively. It causes corrosive, low heating value, high acidity, high viscosity and unstable that causing an engine damage. The presence of phenolic compound decreases the quality of bio-oil. Therefore, it needs a process such as liquid-liquid extraction to reduce the phenolic compound using 80% methanol and 80% chloroform as a solvent. The extract and raffinate phase were analyzed using UV-Vis spectrophotometer. The aim of this research determine the effect of temperature pyrolysis for the characterization of bio-oil, the stirring speed and the temperature of the extraction for the distribution coefficient and the yield of phenolic compound. The results showed that the characterization of bio-oil produced from rice husk pyrolysis at 773 and 873 K are densities 1,040 and 1,042 Kg/m3; viscosities 9.3488 and 9.5007 cSt; acid numbers 46.75 and 52.45 mg KOH/g; pH 2.5 and 3; flash points 426 and 423 K and heating values 3.229 and 3.339 MJ/kg, respectively. The highest distribution coefficient and yield were obtained at 323 K and a stirring speed of 250 rpm. The distribution coefficient of bio-oil produced by pyrolysis at 773 and 873 K is 1.504, and 1.528, respectively. The yields of bio-oil produced by pyrolysis at 773 and 873 K are 58.885%, and 48.429%, respectively.

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Watts, S. "Radar detection prediction in sea clutter using the compound K-distribution model." IEE Proceedings F Communications, Radar and Signal Processing 132, no. 7 (1985): 613. http://dx.doi.org/10.1049/ip-f-1.1985.0115.

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9

Geske, Mark X., Anant P. Godbole, Andrew A. Schaffner, Allison M. Skolnick, and Garrick L. Wallstrom. "Compound Poisson approximations for word patterns under Markovian hypotheses." Journal of Applied Probability 32, no. 4 (December 1995): 877–92. http://dx.doi.org/10.2307/3215201.

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Consider a stationary Markov chain with state space consisting of the ξ -letter alphabet set Λ= {a1, a2, ···, aξ }. We study the variables M=M(n, k) and N=N(n, k), defined, respectively, as the number of overlapping and non-overlapping occurrences of a fixed periodic k-letter word, and use the Stein–Chen method to obtain compound Poisson approximations for their distribution.

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10

Cai, Jun, and Qihe Tang. "On max-sum equivalence and convolution closure of heavy-tailed distributions and their applications." Journal of Applied Probability 41, no. 01 (March 2004): 117–30. http://dx.doi.org/10.1017/s002190020001408x.

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In this paper, we discuss max-sum equivalence and convolution closure of heavy-tailed distributions. We generalize the well-known max-sum equivalence and convolution closure in the class of regular variation to two larger classes of heavy-tailed distributions. As applications of these results, we study asymptotic behaviour of the tails of compound geometric convolutions, the ruin probability in the compound Poisson risk process perturbed by an α-stable Lévy motion, and the equilibrium waiting-time distribution of the M/G/k queue.

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Cai, Jun, and Qihe Tang. "On max-sum equivalence and convolution closure of heavy-tailed distributions and their applications." Journal of Applied Probability 41, no. 1 (March 2004): 117–30. http://dx.doi.org/10.1239/jap/1077134672.

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In this paper, we discuss max-sum equivalence and convolution closure of heavy-tailed distributions. We generalize the well-known max-sum equivalence and convolution closure in the class of regular variation to two larger classes of heavy-tailed distributions. As applications of these results, we study asymptotic behaviour of the tails of compound geometric convolutions, the ruin probability in the compound Poisson risk process perturbed by an α-stable Lévy motion, and the equilibrium waiting-time distribution of the M/G/k queue.

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12

Geske, Mark X., Anant P. Godbole, Andrew A. Schaffner, Allison M. Skolnick, and Garrick L. Wallstrom. "Compound Poisson approximations for word patterns under Markovian hypotheses." Journal of Applied Probability 32, no. 04 (December 1995): 877–92. http://dx.doi.org/10.1017/s0021900200103353.

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Consider a stationary Markov chainwith state space consisting of theξ-letter alphabet set Λ= {a1, a2, ···,aξ}.We study the variablesM=M(n, k) andN=N(n, k),defined, respectively, as the number of overlapping and non-overlapping occurrences of a fixed periodick-letter word, and use the Stein–Chen method to obtain compound Poisson approximations for their distribution.

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13

Kalász, Huba, Zoltán Szimrók, Gellért Karvaly, Jennifer Adeghate, and Kornélia Tekes. "Pharmacokinetics of Two Chlorine-Substituted Bis-Pyridinium Mono-Aldoximes with Regenerating Effect on Butyrylcholinesterase." Molecules 25, no. 5 (March 10, 2020): 1250. http://dx.doi.org/10.3390/molecules25051250.

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Our aim was to find chlorine-substituted antidotes against organophosphate poisoning and compare their pharmacokinetics to their parent compound, K-203. White male Wistar rats were intramuscularly injected with K-203, K-867 or K-870. Serum, brain, kidneys, liver, lung, eyes, and testes tissues were taken after 5, 15, 30, 60, and 120 min and analyzed using reversed-phase high-performance liquid chromatography. K-203, K-867, or K-870 was present in every tissue that was analyzed, including the serum, the eyes, testes, liver, kidneys, lungs, and the brain. The serum levels of K-867 and K-870 (chlorine-substituted derivatives of K-203) were nearly constant between 15 and 30 min, while their parent compound (K-203) showed peak level at 15 min after the administration of 30 µmol/rat. Neither K-203, nor K-867 or K-870 were toxic at a dose of 100 µmol/200 g in rats. Chlorine-substitution of K-867 and K-870 produced limited absorbance and distribution compared to their parent compound, K203.

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14

Freel, Kelle C., Sang-Jip Nam, William Fenical, and Paul R. Jensen. "Evolution of Secondary Metabolite Genes in Three Closely Related Marine Actinomycete Species." Applied and Environmental Microbiology 77, no. 20 (August 26, 2011): 7261–70. http://dx.doi.org/10.1128/aem.05943-11.

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ABSTRACTThe marine actinomycete genusSalinisporais composed of three closely related species. These bacteria are a rich source of secondary metabolites, which are produced in species-specific patterns. This study examines the distribution and phylogenetic relationships of genes involved in the biosynthesis of secondary metabolites in the salinosporamide and staurosporine classes, which have been reported forS. tropicaandS. arenicola, respectively. The focus is on “Salinispora pacifica,” the most recently discovered and phylogenetically diverse member of the genus. Of 61S. pacificastrains examined, 15 tested positive for a ketosynthase (KS) domain linked to the biosynthesis of salinosporamide K, a new compound in the salinosporamide series. Compound production was confirmed in two strains, and the domain phylogeny supports vertical inheritance from a common ancestor shared withS. tropica, which produces related compounds in the salinosporamide series. There was no evidence for interspecies recombination amongsalAKS sequences, providing further support for the geographic isolation of these two salinosporamide-producing lineages. In addition, staurosporine production is reported for the first time forS. pacifica, with 24 of 61 strains testing positive forstaD, a key gene involved in the biosynthesis of this compound. High levels of recombination were observed betweenstaDalleles inS. pacificaand the cooccurring yet more distantly relatedS. arenicola, which produces a similar series of staurosporines. The distributions and phylogenies of the biosynthetic genes examined provide insight into the complex processes driving the evolution of secondary metabolism among closely related bacterial species.

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Barbour, A. D., and Marianne Månsson. "Compound Poisson approximation and the clustering of random points." Advances in Applied Probability 32, no. 01 (March 2000): 19–38. http://dx.doi.org/10.1017/s0001867800009745.

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Let n random points be uniformly and independently distributed in the unit square, and count the number W of subsets of k of the points which are covered by some translate of a small square C. If n|C| is small, the number of such clusters is approximately Poisson distributed, but the quality of the approximation is poor. In this paper, we show that the distribution of W can be much more closely approximated by an appropriate compound Poisson distribution CP(λ1, λ2,…). The argument is based on Stein's method, and is far from routine, largely because the approximating distribution does not satisfy the simplifying condition that iλ i be decreasing.

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Barbour, A. D., and Marianne Månsson. "Compound Poisson approximation and the clustering of random points." Advances in Applied Probability 32, no. 1 (March 2000): 19–38. http://dx.doi.org/10.1239/aap/1013540020.

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Let n random points be uniformly and independently distributed in the unit square, and count the number W of subsets of k of the points which are covered by some translate of a small square C. If n|C| is small, the number of such clusters is approximately Poisson distributed, but the quality of the approximation is poor. In this paper, we show that the distribution of W can be much more closely approximated by an appropriate compound Poisson distribution CP(λ1, λ2,…). The argument is based on Stein's method, and is far from routine, largely because the approximating distribution does not satisfy the simplifying condition that iλi be decreasing.

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Boutsikas, Michael V., and Markos V. Koutras. "On the asymptotic distribution of the discrete scan statistic." Journal of Applied Probability 43, no. 04 (December 2006): 1137–54. http://dx.doi.org/10.1017/s0021900200002485.

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The discrete scan statistic in a binary (0-1) sequence of n trials is defined as the maximum number of successes within any k consecutive trials (n and k, n ≥ k, being two positive integers). It has been used in many areas of science (quality control, molecular biology, psychology, etc.) to test the null hypothesis of uniformity against a clustering alternative. In this article we provide a compound Poisson approximation and subsequently use it to establish asymptotic results for the distribution of the discrete scan statistic as n, k → ∞ and the success probability of the trials is kept fixed. An extreme value theorem is also provided for the celebrated Erdős-Rényi statistic.

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Boutsikas, Michael V., and Markos V. Koutras. "On the asymptotic distribution of the discrete scan statistic." Journal of Applied Probability 43, no. 4 (December 2006): 1137–54. http://dx.doi.org/10.1239/jap/1165505213.

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The discrete scan statistic in a binary (0-1) sequence of n trials is defined as the maximum number of successes within any k consecutive trials (n and k, n ≥ k, being two positive integers). It has been used in many areas of science (quality control, molecular biology, psychology, etc.) to test the null hypothesis of uniformity against a clustering alternative. In this article we provide a compound Poisson approximation and subsequently use it to establish asymptotic results for the distribution of the discrete scan statistic as n, k → ∞ and the success probability of the trials is kept fixed. An extreme value theorem is also provided for the celebrated Erdős-Rényi statistic.

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Kasmadi, Kasmadi, Budi Nugroho, Atang Sutandi, and Syaiful Anwar. "Filter Cake Utilization as Filler of 15-15-15+5S Compound Fertilizer: Particle Size Distribution and Granule Crushing Strength Properties." Reaktor 19, no. 4 (December 31, 2019): 145–51. http://dx.doi.org/10.14710/reaktor.19.4.145-151.

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Compound fertilizer which combining organic-inorganic materials need to be developed to improve the effectivness of fertilizers in the soil. Filter cake as a material has highly potential to be used as a filler in physical process granulation of compound fertilizer. In this study, the particle size distribution and granule crushing strength properties were tested using 15-15-15 + 5S fertilizer compound formula, which are varied in the filler composition and K sources. Potassium sources consisted of 2 (two) types of fertilizers i.e KCl and K2SO4. Filler composition as a binder in fertilizer granulation consists of 5 combination filter cake and clay ratios (60:40, 70:30, 80:20, 90:10 and 100:0). Granulation carried out by the granulation method using pan granulator of 2 kg/batch capacity, 23 rpm rotation speed and 50o pan slope. The results of the research showed that statistically the combination of filter cake and clay 70:30 had a size distribution and hardness of granules not significantly different from standard fertilizer (100% clay). Keywords: crushing strength; filler; filter cake; granulation; size distribution

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RAPAPORT, ARIEL. "Compound Poisson statistics for multiple returns in shrinking cylinders for mixing processes." Ergodic Theory and Dynamical Systems 36, no. 5 (February 11, 2015): 1616–43. http://dx.doi.org/10.1017/etds.2014.139.

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Given a periodic point ${\it\omega}$ in a ${\it\psi}$-mixing shift with countable alphabet, the sequence $\{S_{n}\}$ of random variables counting the number of multiple returns in shrinking cylindrical neighborhoods of ${\it\omega}$ is considered. Necessary and sufficient conditions for the convergence in distribution of $\{S_{n}\}$ are obtained, and it is shown that the limit is a Pólya–Aeppli distribution. A global condition on the shift system which guarantees the convergence in distribution of $\{S_{n}\}$ for every periodic point is introduced. This condition is used to derive results for $f$-expansions and Gibbs measures. Results are also obtained concerning the possible limit distribution of sub-sequences $\{S_{n_{k}}\}$. A family of examples in which there is no convergence is presented. We also exhibit an example for which the limit distribution is pure Poissonian.

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Yeo, Lily, and Kenneth DM Harris. "Temperature-dependent structural properties of a solid urea inclusion compound containing chiral guest molecules: 2-bromotetradecane/urea." Canadian Journal of Chemistry 77, no. 12 (December 5, 1999): 2105–18. http://dx.doi.org/10.1139/v99-215.

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Periodic structural properties of the 2-bromotetradecane/urea inclusion compound have been investigated as a function of temperature. Differential scanning calorimetry between 298 and 98 K identified three well-defined regimes, denoted the high-, intermediate-, and low-temperature phases. The structural properties of each phase (at 293, 207, and 142 K, respectively) have been investigated by single crystal X-ray diffraction. In the high-temperature phase, the inclusion compound has the hexagonal urea tunnel structure (P6122) characteristic of the conventional urea inclusion compounds, with substantial orientational disorder of the guest molecules. In the intermediate-temperature phase, the symmetry is lowered to orthorhombic (C2221), although the host structure remains close to the hexagonal tunnel structure of the high-temperature phase and there is no clear evidence for increased orientational ordering of the guest molecules. In the low-temperature phase, the urea tunnel structure is monoclinic (P21), and is based on a 2 × 2 × 1 supercell of the hexagonal cell of the high-temperature structure. There are four independent types of tunnel, three of which are strongly distorted from hexagonal geometry. Within these distorted tunnels, there is a comparatively narrow distribution of guest molecule orientations, which correlate well with the observed distortions of the tunnels. The 2-bromotetradecane/urea inclusion compound highlights several issues of wider relevance concerning the structural properties of solid inclusion compounds.Key words: urea inclusion compounds, X-ray diffraction, phase transitions, chiral recognition, incommensurate solid, 2-bromotetradecane/urea.

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Hansen, Anna-Lena, Bastian Dietl, Martin Etter, Reinhard K. Kremer, David C. Johnson, and Wolfgang Bensch. "Temperature-dependent synchrotron X-ray diffraction, pair distribution function and susceptibility study on the layered compound CrTe3." Zeitschrift für Kristallographie - Crystalline Materials 233, no. 6 (June 27, 2018): 361–70. http://dx.doi.org/10.1515/zkri-2017-2100.

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Abstract Results of combined synchrotron X-ray diffraction and pair distribution function experiments performed on the layered compound CrTe3 provide evidence for a short range structural distortion of one of the two crystallographically independent CrTe6 octahedra. The distortion is caused by higher mobility of one crystallographically distinct Te ion, leading to an unusual large Debye Waller factor. In situ high temperature X-ray diffraction investigations show an initial crystallization of a minor amount of elemental Te followed by decomposition of CrTe3 into Cr5Te8 and Te. Additional experiments provide evidence that the Te impurity (<1%) cannot be avoided. Analyses of structural changes in the temperature range 100–754 K show a pronounced anisotropic expansion of the lattice parameters. The differing behavior of the crystal axes is explained on the basis of structural distortions of the Cr4Te16 structural building units. An abrupt distortion of the structure occurs at T≈250 K, which then remains nearly constant down to 100 K. The structural distortion affects the spin exchange interactions between Cr3+ cations. A significant splitting between field-cooled (fc) and zero-field-cooled (zfc) magnetic susceptibility is observed below about 200 K. Applying a small external magnetic field results in a substantial spontaneous magnetization, reminiscent of ferro- or ferrimagnet exchange interactions below ~240 K. A Debye temperature of ~150 K was extracted from heat capacity measurements.

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Wang, Xiaoxin, and Aihua Xia. "On Negative Binomial Approximation to k-Runs." Journal of Applied Probability 45, no. 2 (June 2008): 456–71. http://dx.doi.org/10.1239/jap/1214950360.

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The distributions of the run occurrences for a sequence of independent and identically distributed (i.i.d.) experiments are usually obtained by combinatorial methods (see Balakrishnan and Koutras (2002, Chapter 5)) and the resulting formulae are often very tedious, while the distributions for non i.i.d. experiments are generally intractable. It is therefore of practical interest to find a suitable approximate model with reasonable approximation accuracy. In this paper we demonstrate that the negative binomial distribution is the most suitable approximate model for the number of k-runs: it outperforms the Poisson approximation, the general compound Poisson approximation as observed in Eichelsbacher and Roos (1999), and the translated Poisson approximation in Rollin (2005). In particular, its accuracy of approximation in terms of the total variation distance improves when the number of experiments increases, in the same way as the normal approximation improves in the Berry-Esseen theorem.

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Song, Huang. "Hydrochemistry Research of Intercrystalline with Pore Brine and Pre-3D Modelling of Heibeiwadi Brine Deposit." Key Engineering Materials 783 (October 2018): 170–75. http://dx.doi.org/10.4028/www.scientific.net/kem.783.170.

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Intercrystalline and pore brine develop extensively in the Heibewadi research area which is located at south foot of Altun mountain of Qaidam basin. In central area, intercrystalline brine’s depths range from 5m to 90m. In northwest, south area and central deeper area, pore brine develops under intercrystalline brine layer. The 2 types of aquifers have strong yield property, TDS is 200-350g/l with average of 276g/l. Main salt compound can be mined out economically. According to analysis result of intercrystalline brine, TDS, Cl-, Na+, K+, Mg2+, Li+ irons’ grades are very steady. That mean intercrystalline brine exist in the water-salt system under balance. Only the stability of Ca2+ and SO42- are slightly poor. According the Kurtosis characteristics analysis, Ca2+, SO42- are no-normal positively platykurtic distribution, K+, Cl- and PH are normal positively platykurtic distribution. These 2 groups fall into a sub-class. And the combined with normal negatively platykurtic distribution-TDS and fall into platykurtic distribution group. Mg2+, Li+ are normal positively peaked distribution; Na+ is normal negatively peaked distribution. They all belong to peaked distribution group. According to Na+, K+, Mg2+//Cl-H2O quarternary phase diagram and Na+, K+, Mg2+//Cl-SO42-H2O pentabasic phase diagram, the chlorite and magnesium sulfate subtype have different hydro chemical characteristics and salting-in and salting-out rules.

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JOHN BOSCO BALAGURU, R., N. LAWRENCE, and S. ALFRED CECIL RAJ. "LATTICE INSTABILITY OF 2H-TaSe2." International Journal of Modern Physics B 16, no. 27 (October 30, 2002): 4111–25. http://dx.doi.org/10.1142/s0217979202012153.

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The charge density wave (CDW) in the layered compound 2H-TaSe 2 at low temperatures has a commensurate phase, which causes super lattice points to appear in the Brillöuin zone of the undistorted phase. A Born-von Karman formalism has been employed for the calculation of phonon frequency distribution curves of 2H-TaSe 2 both in the normal and in the commensurate charge density wave (CCDW) phases. A folding technique has been adopted for the calculation in the CCDW phase. The phonon distribution for both the phases have been reported. With these distributions the thermal properties such as specific heat capacity, Debye Waller factor W(k) and thermal conductivity have been worked out, and compared with the available experimental results.

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Boutsikas, M. V., M. V. Koutras, and F. S. Milienos. "Asymptotic results for the multiple scan statistic." Journal of Applied Probability 54, no. 1 (March 2017): 320–30. http://dx.doi.org/10.1017/jpr.2016.102.

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AbstractThe contribution of the theory of scan statistics to the study of many real-life applications has been rapidly expanding during the last decades. The multiple scan statistic, defined on a sequence of n Bernoulli trials, enumerates the number of occurrences of k consecutive trials which contain at least r successes among them (r≤k≤n). In this paper we establish some asymptotic results for the distribution of the multiple scan statistic, as n,k,r→∞ and illustrate their accuracy through a simulation study. Our approach is based on an appropriate combination of compound Poisson approximation and random walk theory.

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FELNER, I., U. ASAF, Y. LEVI, and O. MILLO. "THE EFFECT OF OXYGEN ON SUPERCONDUCTIVITY AND MAGNETISM IN Eu1.5Ce0.5RuSr2Cu2O10 +δ." International Journal of Modern Physics B 13, no. 29n31 (December 20, 1999): 3650–54. http://dx.doi.org/10.1142/s021797929900360x.

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The Eu 1.5 Ce 0.5 RuSr 2 Cu 2 O 10+δ compound is the first known Cu-O based material in which superconductivity (SC) and weak-ferromagnetism (W-FM) coexist (T c =32 K, T M =122 K). SC is confined to the CuO 2 planes, and the magnetic ordering is due to the Ru sublattice. For as-prepared samples (APS), the normal-state resistivity is characteristic of an under-doped SC compound. The hole doping in CuO 2 planes, can be achieved with appropriate variation of the oxygen concentrations, which is obtained by annealing the APS under oxygen pressures up to 150 atm. The effect of oxygen treatment is to shift the onset of SC monotonically, up to 49 K. For 75 atm., two transition temperatures are found, indicating the existence of two SC phases. At the same time, scanning tunneling spectroscopy measurements show spatial variations of the gap with a double-peak distribution.

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Halder, Maurice, Ploingarm Petsophonsakul, Asim Akbulut, Angelina Pavlic, Frode Bohan, Eric Anderson, Katarzyna Maresz, Rafael Kramann, and Leon Schurgers. "Vitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease." International Journal of Molecular Sciences 20, no. 4 (February 19, 2019): 896. http://dx.doi.org/10.3390/ijms20040896.

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Vitamin K is an essential bioactive compound required for optimal body function. Vitamin K can be present in various isoforms, distinguishable by two main structures, namely, phylloquinone (K1) and menaquinones (K2). The difference in structure between K1 and K2 is seen in different absorption rates, tissue distribution, and bioavailability. Although differing in structure, both act as cofactor for the enzyme gamma-glutamylcarboxylase, encompassing both hepatic and extrahepatic activity. Only carboxylated proteins are active and promote a health profile like hemostasis. Furthermore, vitamin K2 in the form of MK-7 has been shown to be a bioactive compound in regulating osteoporosis, atherosclerosis, cancer and inflammatory diseases without risk of negative side effects or overdosing. This review is the first to highlight differences between isoforms vitamin K1 and K2 by means of source, function, and extrahepatic activity.

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Delgado, G. E., P. Grima-Gallardo, J. A. Aitken, A. Cárdenas, and I. Brito. "The new P-chalcopyrite compound Cu2FeIn2Se5; synthesis, thermal analysis (DTA), and crystal structure analysis by X-ray powder diffraction (XRPD)." Revista Mexicana de Física 67, no. 1 Jan-Feb (January 7, 2021): 18. http://dx.doi.org/10.31349/revmexfis.67.18.

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The Cu2FeIn2Se5 alloy, belonging to the system (CuInSe2)1-x(FeSe)x with x= ⅓, was synthesized by the melt and annealing technique. The differential thermal analysis (DTA) indicates that this compound melts at 1017 K. The crystal structure of this new quaternary compound was established using powder X-ray diffraction. Cation distribution analysis indicates that this material crystallizes in a P-chalcopyrite structure, space group P2c (Nº 112), with unit cell parameters a = 6.1852(2) Å, c = 12.3633(9) Å, V = 472.98(4) Å3. Cu2FeIn2Se5 is a new adamantane type compound derivative of the sphalerite structure, and consists of a three-dimensional arrangement of distorted CuSe4, FeSe4, and InSe4 tetrahedral connected by common faces.

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30

Delgado, G. E., P. Grima-Gallardo, J. A. Aitken, A. Cárdenas, and I. Brito. "The new P-chalcopyrite compound Cu2FeIn2Se5; synthesis, thermal analysis (DTA), and crystal structure analysis by X-ray powder diffraction (XRPD)." Revista Mexicana de Física 67, no. 1 Jan-Feb (January 7, 2021): 18–24. http://dx.doi.org/10.31349/revmexfis.67.18.

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The Cu2FeIn2Se5 alloy, belonging to the system (CuInSe2)1-x(FeSe)x with x= ⅓, was synthesized by the melt and annealing technique. The differential thermal analysis (DTA) indicates that this compound melts at 1017 K. The crystal structure of this new quaternary compound was established using powder X-ray diffraction. Cation distribution analysis indicates that this material crystallizes in a P-chalcopyrite structure, space group P2c (Nº 112), with unit cell parameters a = 6.1852(2) Å, c = 12.3633(9) Å, V = 472.98(4) Å3. Cu2FeIn2Se5 is a new adamantane type compound derivative of the sphalerite structure, and consists of a three-dimensional arrangement of distorted CuSe4, FeSe4, and InSe4 tetrahedral connected by common faces.

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31

Pérez, Tzayam, and José L. Nava. "Simulations of a Single-Phase Flow in a Compound Parabolic Concentrator Reactor." International Journal of Photoenergy 2018 (August 19, 2018): 1–8. http://dx.doi.org/10.1155/2018/2569251.

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This paper deals with the analysis and interpretation of flow visualization and residence time distribution (RTD) in a compound parabolic concentrator (CPC) reactor using computational fluid dynamics (CFD). CFD was calculated under turbulent flow conditions solving the Reynolds averaged Navier–Stokes (RANS) equation expressed in terms of turbulent viscosity and the standard k−ε turbulent model in 3D. A 3D diffusion-convection model was implemented in the CPC reactor to determine the RTD. The fluid flow visualization and RTD were validated with experimental results. The CFD showed that the magnitude of the velocity field remains almost uniform in most of the bulk reactor, although near and inside the 90° connectors and the union segments, the velocity presented low- and high-speed zones. Comparisons of theoretical and experimental RTD curves showed that the k−ε model is appropriate to simulate the nonideal flow inside the CPC reactor under turbulent flow conditions.

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32

Dias, Marta, Patrícia Almeida Carvalho, Isabel Cordeiro dos Santos, Olivier Tougait, Ladislav Havela, and António Pereira Gonçalves. "HOLZ Rings in EBSD Patterns of the UFeB4 Compound: Association with a Random Distribution of Planar Defects." Microscopy and Microanalysis 19, no. 5 (September 17, 2013): 1204–10. http://dx.doi.org/10.1017/s1431927613013366.

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AbstractThe UFeB4 phase present in different alloys of the B–Fe–U system was studied by powder X-ray diffraction (PXRD) and scanning electron microscopy complemented with energy-dispersive spectroscopy and electron backscattered diffraction (EBSD). The PXRD data showed that the ternary compound crystallized adopting essentially the YCrB4-type structure. However, microstructural observations revealed that under high undercooling conditions the UFeB4 phase exhibits a random distribution of defects parallel to, which are consistently associated with intense higher-order Laue zone rings in EBSD patterns. Indexation of the EBSD patterns showed that the defective structure is compatible with an intergrowth of YCrB4- and ThMoB4-type layers according to the (010)YCrB4//(110)ThMoB4 and [001]YCrB4//[001]ThMoB4 orientation relation previously reported for an analogous compound. Magnetic studies indicated that the annealed UFeB4 compound has a paramagnetic behavior in the 2–300 K temperature range.

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33

Fodil, Hamzaoui, and Chouaih Abdelkader. "The electron charge density distribution in a non linear optical compound." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C380. http://dx.doi.org/10.1107/s2053273314096193.

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The 4, 4 dimethyl amino-cyanobiphenyl crystal (DMACB) is characterized by its nonlinear optical properties. The intra molecular charge transfer of this molecule (figure-1) results mainly from the electronic transmission of the electro-acceptor (Cyano) and the electro-donor (Di-Methyl-Amino) groups [1]. An accurate electron charge density distribution around the molecule has been calculated from a high-resolution X-ray diffraction study. The data were collected at 123 K using graphite-monochromated Mo-Kα radiation. The crystal structure has been validated and deposited at the Cambridge Crystallographic Data Centre with the deposition number CCDC 876507. The refinement was carried using the multipolar model of Hansen and Coppens [2]. We have explored systematically the main molecule planes. The different sections show clearly the accumulation of the electron charge density along the chemical bonding. The oxygen lone pairs have been perfectly localized. The charge density function has been used for the calculation of the molecular dipole moment and the electrostatic potential around the molecule [3]. The obtained results show clearly the nature of electron charge transfer in the DMACB compound.

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34

Fleck, Silvia, and Alarich Weiss. "Dielectric and Pyroelectric Properties of Lithium Hydrogen Dimalate, LiH3(C4H4O5)2." Zeitschrift für Naturforschung A 41, no. 11 (November 1, 1986): 1289–96. http://dx.doi.org/10.1515/zna-1986-1104.

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The dielectric constant and the pyroelectric coefficient at constant stress of 1-lithium hydrogen dimalate 1-Li⊕(OOCCHOHCH2COOH)⊖(HOOCCHOHCH2COOH), were investigated in the temperature range 200 ≦ T / K ≦ Td (decomposition temperature) and 100 ≦ T / K ≦ Td, respectively. The compound crystallizes in the space group P21. In the direction of the 21 axis ε'22 increases with almost constant slope with increasing temperature from 7.32 (200 K) to 8.55 (360 K). The pyroelectric coefficient p2 shows a maximum at 152 K and a minimum at 290 K; p2 lies between 15 μC m-2 K-1 and 6 μC m-2 K-1. The contribution of the lattice to the polarization was calculated on the basis of a point charge model developed from a charge distribution calculation on the INDO basis. Assuming certain lattice vibration frequencies and a harmonic oscillator model, p2 = ƒ(T) was calculated.Qualitatively the calculations are in satisfactory agreement with the experiment.

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35

Issaoui, Chokri, Hammouda Chebbi, and Abderrahmen Guesmi. "Crystal structure of Na4Co7−xAl0.67x(As1−yPyO4)6(x = 1.60;y= 0.116)." Acta Crystallographica Section E Crystallographic Communications 72, no. 4 (March 15, 2016): 495–97. http://dx.doi.org/10.1107/s205698901600400x.

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The title compound, tetrasodium hepta(cobalt/aluminium) hexa(arsenate/phosphate), Na4Co5.40Al1.07(As0.883P0.116O4)6, was prepared by a solid-state reaction. It is a new member of the family of isostructural compounds with the general formulaA4M7(XO4)6(A: Na, K;M: Ni, Co;X: P, As) that is most similar to Na4Co5.63Al0.91(AsO4)6. The Co2+ions in the title compound are substituted by Al3+in a fully occupied octahedral site (site symmetry 2/m) and a partially occupied tetrahedral site (site symmetry 2). A third octahedral site is fully occupied by Co2+ions only. With regard to the P and As atoms, one site (site symmetrym) is simultaneously occupied by As and P, whereas in the second site there is only arsenic. The alkali cations are, as in the isostructural compounds, distributed over half-occupied crystallographic sites, with a positional disorder of one of them. The proposed structural model is based both on a careful investigation of the crystal data, as well as validation by means of bond-valence-sum (BVS) and charge-distribution (CHARDI) calculations. The correlation between the X-ray refinement and the validation results is discussed.

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36

Drokina, Tamara V., German A. Petrakovskii, Dmitrii A. Velikanov, and Maksim S. Molokeev. "X-Ray and Magnetic Measurements of TmFeTi₂O₇." Solid State Phenomena 215 (April 2014): 470–73. http://dx.doi.org/10.4028/www.scientific.net/ssp.215.470.

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In this paper we are reported about a peculiarity of the crystal structure and the magnetic state of TmFeTi2O7. The compound TmFeTi2O7 has been synthesizedusing the solid-phase reaction method. Using X-ray diffraction method the disorder in the distribution of the iron ions over five nonequivalent crystal sites was observed, also the populations of the iron atoms positions were determined. We show that below Tf = 6 K the magnetization of TmFeTi2O7 depends on the magnetic history of the sample. There are indications for spin glass state. This results allow us to assume the state of spin glass is realized below freezing temperature Tf = 6 K in TmFeTi2O7.

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37

Setyawati, I. A., K. H. Thompson, V. G. Yuen, Y. Sun, M. Battell, D. M. Lyster, C. Vo, et al. "Kinetic analysis and comparison of uptake, distribution, and excretion of 48V-labeled compounds in rats." Journal of Applied Physiology 84, no. 2 (February 1, 1998): 569–75. http://dx.doi.org/10.1152/jappl.1998.84.2.569.

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Setyawati, I. A., K. H. Thompson, V. G. Yuen, Y. Sun, M. Battell, D. M. Lyster, C. Vo, T. J. Ruth, S. Zeisler, J. H. McNeill, and C. Orvig. Kinetic analysis and comparison of uptake, distribution, and excretion of48V-labeled compounds in rats. J. Appl. Physiol. 84(2): 569–575, 1998.—Vanadium has been found to be orally active in lowering plasma glucose levels; thus it provides a potential treatment for diabetes mellitus. Bis(maltolato)oxovanadium(IV) (BMOV) is a well-characterized organovanadium compound that has been shown in preliminary studies to have a potentially useful absorption profile. Tissue distributions of BMOV compared with those of vanadyl sulfate (VS) were studied in Wistar rats by using48V as a tracer. In this study, the compounds were administered in carrier-added forms by either oral gavage or intraperitoneal injection. Data analyzed by a compartmental model, by using simulation, analysis, and modeling (i.e., SAAM II) software, showed a pattern of increased tissue uptake with use of48V-BMOV compared with48VS. The highest48V concentrations at 24 h after gavage were in bone, followed by kidney and liver. Most ingested48V was eliminated unabsorbed by fecal excretion. On average, 48V concentrations in bone, kidney, and liver 24 h after oral administration of 48V-BMOV were two to three times higher than those of48VS, which is consistent with the increased glucose-lowering potency of BMOV in acute glucose lowering compared with VS.

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38

Rostami, Abbas, Seyyed Khatiboleslam Sadrnezhaad, and Gholam Ali Bagheri. "Production of Nanostructured Ni-Ti-Ag Alloy by Mechanical Alloying." Advanced Materials Research 829 (November 2013): 67–72. http://dx.doi.org/10.4028/www.scientific.net/amr.829.67.

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Because of corrosion resistance and antibacterial effects, shape memory Ni-Ti-Ag alloy can be considered for different biomedical applications. Mechanical alloying is used to produce nanostructured Ni-Ti-Ag alloy from elemental powders. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) are used to characterize the product. Results show that after 1h milling, homogenous distribution of the elements occurs; while no intermetallic compounds is observed. After 3h milling, titanium dissolves in nickel to form amorphous and nanostructured solid phases. Peaks of B2 phase appear in the XRD pattern after the 3h milling of the powder mixture. Sintering of the 3h-milled mixture at 1223 K leads to the formation of NiTi intermetallic compound; while titanium disappears, the content of the element nickel reduces and grain growth takes place.

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39

Pah, Lim Kean, Abdul Halim Shaari, Chen Soo Kien, Chin Hui Wei, Albert Gan, Ng Siau Wei, and Chong Kuen Hou. "Effect of Sintering Temperature on the Microstructure, Electrical and Magnetotransport Properties of La_0.67Sr_0.33MnO₃ Compound." Advanced Materials Research 895 (February 2014): 319–22. http://dx.doi.org/10.4028/www.scientific.net/amr.895.319.

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In this work, we report the effect of sintering temperature (900°C, 1000°C, 1100°C and 1200°C) on the electrical and magnetotransport properties of polycrystalline La0.67Sr0.33MnO3 (LSMO). Single phase of LSMO hexagonal structure (R-3c) accompanied with minor phases was successfully synthesized by co-precipitation method. With increasing sintering temperature, grain growth was promoted and grain connectivity was improved. It was found that an enhancement of resistivity on smaller grain size was due to larger grain surface over volume (grain boundaries effect). The shifting of the metal-insulator transition (TMI) to higher temperature was also responsible for observed changes in physical properties. TMI of 900°C, 1000°C and 1100°C were 232 K, 278 K and 298 K respectively however 1200°C was out of measurement range (higher than 300 K). In summary, CP900 with smaller grain size distribution (~200 nm) displayed the highest resistivity and MR% of -19.2% (at 80 K, 10 kG).

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40

Firdausy, Alif Firman, Roihatul Muti'ah, and Eka Kartini Rahmawati. "Predicting Pharmacokinetic Profiles of Sunflower’s (Helianthus annuus L.) Active Compounds using in Silico Approach." Journal of Islamic Medicine 4, no. 1 (April 3, 2020): 1–7. http://dx.doi.org/10.18860/jim.v4i1.8840.

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Introduction: Sunflower (Heliantus annuus L.) widely known as medicinal plant for treating several diseases, such as hypertension, allergy, pain, inflammation, and cancer. It contains various bioactive compounds which some of them were hellianuols. Hellianuols are a sesquiterpene lactones which marked by benzene fused 6- to 8-membered cyclic ether ring structure. To make sure that hellianuols were adequate for development as a new chemical entities, we predicted some pharmacokinetic parameters of several hellianuols compounds (A to L) through in silico approach.Methods: We constructed 3 dimensional structures of hellianuol A, B, C, D, E, F, G, H, I, J, K and L then generated the SMILE codes of each compound. These codes then used as main material for running pkCSM online tool to predict absorption, distribution, metabolism, and excretion profile of each compounds.Results: Helianuols predicted to be well absorbed in intestine (90,793% to 95,384% permeability), skin (Log Kp: -2,662 to -3,570), and high permeability against monolayer Caco-2 cell lines (LogPapp: 1,186 to 1,341 ×10-6cm/s). Unfortunately, it had been predicted that hellianuols does not well distributed in the body based on volume of distribution at steady state (VDSS: 0,094 to 0,317) value. But its also predicted that most of hellianuols had a capability to pass through blood-brain barriers (LogBBB: up to 0,389) and penetrated into central nervous system as well. Only hellianuol G, H and K predicted to be metabolized by CYP1A2 inhibitor and only hellianuol A, B, D, E and K metabolized by CYP2C19. Also predicted that hellianuols were excreted in around 0,719 to 1,082 mg/kg/day.Conclusion: Hellianuols contained in leaf aqueous extract of sunflower predicted to be a good new pharmaceutical entities candidate based on its pharmacokinetic profiles.Keywords: Hellianuol, sunflower, pharmacokinetic profie, pkCSM online tool

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41

Gaudin, E., L. Fischer, F. Boucher, M. Evain, and V. Petricek. "Ag2Ti2P2S11: A New Layered Thiophosphate. Synthesis, Structure Determination and Temperature Dependence of the Silver Distribution." Acta Crystallographica Section B Structural Science 53, no. 1 (February 1, 1997): 67–75. http://dx.doi.org/10.1107/s010876819601097x.

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The new Ag2Ti2P2S11 quaternary phosphosulfide disilver dititanium undecathiodiphosphate is obtained by heating the elements at ca 850 K in an evacuated silica tube. It crystallizes in orthorhombic symmetry, Pnma space group, with a = 8.5222 (11), b = 6.8359 (10), c = 24.142 (4) Å, V = 1406.4 (4) Å3 and Z = 4 at 293 K. The refinement of the room-temperature structure leads to a reliability factor of R = 0.0378 for 1556 independent reflections and 128 variables. Ag2Ti2P2S11 is composed of layers, separated by van der Waals gaps. The layers are composed of [Ti2S9] chains built from [TiS7] units (TiS6 octahedra in which a corner has been replaced by an S2 pair) and linked through regular [PS4] and highly distorted [AgS4] tetrahedra. The formula of the compound can be written as AgI 2TiIV 2PV 2(S2)−IIS−II 9. A Gram–Charlier anharmonic development of the atomic displacement factor for Ag atoms reveals a strong non-harmonic probability density deformation, especially in the direction of two empty neighbouring tetrahedra, away from the Ti and P cations. The temperature dependence of the effective one-particle potential shows that the Ag distribution is primarily static in nature. At high temperature the tetrahedrally coordinated site is the preferential site. At lower temperature the Ag atoms are redistributed over the tetrahedral site and the adjacent triangular site. The disorder could not be resolved due to a phase transition with splitting of spots just below room temperature.

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Jones, K. S., and C. J. Santana. "Amorphization of elemental and compound semiconductors upon ion implantation." Journal of Materials Research 6, no. 5 (May 1991): 1048–54. http://dx.doi.org/10.1557/jmr.1991.1048.

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Cross-sectional TEM studies of ion implantation induced amorphization in a large number of semiconductors have been performed. Samples of Si, AlAs, GaAs, GaP, GaSb, InP, InAs, and ZnSe were simultaneously implanted at 77 K with 20 keV Si+ at doses between 1 × 1014/cm2 and 1 × 1016/cm2. A dose of 1 × 1015/cm2 minimized the ion beam induced epitaxial crystallization and sputtering effects. The depth of the amorphous layer at this dose was compared with Monte Carlo damage density distribution calculations (TRIM'90). The threshold damage density (TDD) necessary for amorphization was determined for each compound. The values of the threshold damage density vary from as low as 2.4 × 1019 keV/cm3 for InAs up to 7.3 × 1020 keV/cm3 for AlAs. ZnSe never became amorphous and GaSb exhibited an unusual disordering after the highest dose. The values of the threshold damage density for the various compositions were compared with known thermochemical data and several bond energy estimates. No single calculation explained all of the trends observed.

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43

Sever, Belgin, Mehlika Dilek Altıntop, Yeliz Demir, Cüneyt Türkeş, Kaan Özbaş, Gülşen Akalın Çiftçi, Şükrü Beydemir, and Ahmet Özdemir. "A new series of 2,4-thiazolidinediones endowed with potent aldose reductase inhibitory activity." Open Chemistry 19, no. 1 (January 1, 2021): 347–57. http://dx.doi.org/10.1515/chem-2021-0032.

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Abstract In an effort to identify potent aldose reductase (AR) inhibitors, 5-(arylidene)thiazolidine-2,4-diones (1–8), which were prepared by the solvent-free reaction of 2,4-thiazolidinedione with aromatic aldehydes in the presence of urea, were examined for their in vitro AR inhibitory activities and cytotoxicity. 5-(2-Hydroxy-3-methylbenzylidene)thiazolidine-2,4-dione (3) was the most potent AR inhibitor in this series, exerting uncompetitive inhibition with a K i value of 0.445 ± 0.013 µM. The IC50 value of compound 3 for L929 mouse fibroblast cells was determined as 8.9 ± 0.66 µM, pointing out its safety as an AR inhibitor. Molecular docking studies suggested that compound 3 exhibited good affinity to the binding site of AR (PDB ID: 4JIR). Based upon in silico absorption, distribution, metabolism, and excretion data, the compound is predicted to have favorable pharmacokinetic features. Taking into account the in silico and in vitro data, compound 3 stands out as a potential orally bioavailable AR inhibitor for the management of diabetic complications as well as nondiabetic diseases.

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44

Pan, Diangang, Lu Li, Junyu Yang, and Hong Chang. "Magnetic Properties and Carrier Transport of Ir0.9Mn1−xSn1.1+x." Materials 12, no. 2 (January 16, 2019): 283. http://dx.doi.org/10.3390/ma12020283.

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The nonstoichiometric Ir0.9Mn1−xSn1.1+x (x = 0.1, 0.05, and −0.05) are crystallized in half-Heusler alloys. The magnetic transition is observed at 77 K for x = 1.05, and it decreases with the decreasing Mn content. It is proven to be a ferromagnetic transition with a nonlinear magnetic moment alignment, as the magnetization is not saturated at 70 kOe. The different magnetic behavior than a typical ferromagnet (FM is due to the Ir ions with strong spin orbital coupling (SOC). The different hysteresis loops reflect that the ionic distribution is not completely homogeneous. The high coercivity observed in the cubic compound is due to the strong single-ion anisotropy of the Ir ions. A metallic-semiconducting transition at 130 K is observed in Ir0.9Mn1.05Sn1.05. A negative magnetoresistance is observed at 2 K and 14 T with the value as −2.6%.

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45

Li, Shuanming, and José Garrido. "On a general class of renewal risk process: analysis of the Gerber-Shiu function." Advances in Applied Probability 37, no. 03 (September 2005): 836–56. http://dx.doi.org/10.1017/s0001867800000501.

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We consider a compound renewal (Sparre Andersen) risk process with interclaim times that have a K n distribution (i.e. the Laplace transform of their density function is a ratio of two polynomials of degree at most n ∈ N). The Laplace transform of the expected discounted penalty function at ruin is derived. This leads to a generalization of the defective renewal equations given by Willmot (1999) and Gerber and Shiu (2005). Finally, explicit results are given for rationally distributed claim severities.

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46

Northrop, Judith A., and Antonia Papandreou-Suppappola. "Computationally Efficient Estimation of Compound K-Distribution Sea Clutter in Thermal Noise and Its Application to Sea Echo Reflectivity Observations." IEEE Transactions on Aerospace and Electronic Systems 56, no. 3 (June 2020): 2340–50. http://dx.doi.org/10.1109/taes.2019.2949395.

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47

Bianchi, R., G. Gervasio, and G. Viscardi. "Experimental Electron-Density Study of 4-Cyanoimidazolium-5-olate at 120 K." Acta Crystallographica Section B Structural Science 54, no. 1 (February 1, 1998): 66–72. http://dx.doi.org/10.1107/s0108768197009269.

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This paper presents an analysis of the electron density in 4-cyanoimidazolium-5-olate, determined by the rigid pseudoatom model from accurate X-ray data measured at 120 K. A comparison of the electrostatic potential between experiment and theory is given for the isolated molecule. The results confirm the typical mesoionic electron distribution of the title compound and the presence of three hydrogen bonds in the crystal structure. The atomic charges and molecular dipole moment derived from the ab initio Hartree–Fock method are close to those obtained from the multipole model, which includes the kappa radial parameters. Electrostatic energies are also calculated for hydrogen bonding and molecular stacking interactions.

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Schäfer, Marion C., and Svilen Bobev. "K and Ba distribution in the structures of the clathrate compounds KxBa16−x(Ga,Sn)136(x= 0.8, 4.4, and 12.9) and KxBa8−x(Ga,Sn)46(x= 0.3)." Acta Crystallographica Section C Crystal Structure Communications 69, no. 4 (March 12, 2013): 319–23. http://dx.doi.org/10.1107/s0108270113006203.

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Studies of the K–Ba–Ga–Sn system produced the clathrate compounds K0.8(2)Ba15.2(2)Ga31.0(5)Sn105.0(5)[a= 17.0178 (4) Å], K4.3(3)Ba11.7(3)Ga27.4(4)Sn108.6(4)[a= 17.0709 (6) Å] and K12.9(2)Ba3.1(2)Ga19.5(4)Sn116.5(4)[a= 17.1946 (8) Å], with the type-II structure (cubic, space groupFd\overline{3}m), and K7.7(1)Ba0.3(1)Ga8.3(4)Sn37.7(4)[a= 11.9447 (4) Å], with the type-I structure (cubic, space groupPm\overline{3}n). For the type-II structures, only the smaller (Ga,Sn)24pentagonal dodecahedral cages are filled, while the (Ga,Sn)28hexakaidecahedral cages remain empty. The unit-cell volume is directly correlated with the K:Ba ratio, since an increasing amount of monovalent K occupying the cages causes a decreasing substitution of the smaller Ga in the framework. All three formulae have an electron count that is in good agreement with the Zintl–Klemm rules. For the type-I compound, all framework sites are occupied by a mixture of Ga and Sn atoms, with Ga showing a preference for Wyckoff site 6c. The (Ga,Sn)20pentagonal dodecahedral cages are occupied by statistically disordered K and Ba atoms, while the (Ga,Sn)24tetrakaidecahedral cages encapsulate only K atoms. Large anisotropic displacement parameters for K in the latter cages suggest an off-centering of the guest atoms.

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Ol’khovich, Marina, Angelica Sharapova, Svetlana Blokhina, and German Perlovich. "Isavuconazole: Thermodynamic Evaluation of Processes Sublimation, Dissolution and Partition in Pharmaceutically Relevant Media." Molecules 26, no. 16 (August 6, 2021): 4759. http://dx.doi.org/10.3390/molecules26164759.

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A temperature dependence of saturated vapor pressure of isavuconazole (IVZ), an antimycotic drug, was found by using the method of inert gas-carrier transfer and the thermodynamic functions of sublimation were calculated at a temperature of 298.15 K. The value of the compound standard molar enthalpy of sublimation was found to be 138.1 ± 0.5 kJ·mol−1. The IVZ thermophysical properties—melting point and enthalpy—equaled 302.7 K and 29.9 kJ mol−1, respectively. The isothermal saturation method was used to determine the drug solubility in seven pharmaceutically relevant solvents within the temperature range from 293.15 to 313.15 K. The IVZ solubility in the studied solvents increased in the following order: buffer pH 7.4, buffer pH 2.0, buffer pH 1.2, hexane, 1-octanol, 1-propanol, ethanol. Depending on the solvent chemical nature, the compound solubility varied from 6.7 × 10−6 to 0.3 mol·L−1. The Hansen s approach was used for evaluating and analyzing the solubility data of drug. The results show that this model well-described intermolecular interactions in the solutions studied. It was established that in comparison with the van’t Hoff model, the modified Apelblat one ensured the best correlation with the experimental solubility data of the studied drug. The activity coefficients at infinite dilution and dissolution excess thermodynamic functions of IVZ were calculated in each of the solvents. Temperature dependences of the compound partition coefficients were obtained in a binary 1-octanol/buffer pH 7.4 system and the transfer thermodynamic functions were calculated. The drug distribution from the aqueous solution to the organic medium was found to be spontaneous and entropy-driven.

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Peral, I., G. Madariaga, A. Pérez-Etxebarria, and T. Breczewski. "X-ray diffraction study of the phase transitions of (CH3)4NCdCl3 between 293 and 80 K: a quantitative analysis of the ferroelastic domains distribution below 118 K." Acta Crystallographica Section B Structural Science 56, no. 2 (April 1, 2000): 215–25. http://dx.doi.org/10.1107/s0108768199013622.

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X-ray diffraction patterns of [N(CH_{3})_{4}][CdCl_{3}], tetramethylammonium trichlorocadmate(II), have been investigated in the temperature range 80–293 K, which includes two phase transitions at 118 and 104 K, respectively. The main interest in this compound is to establish the mechanism of the structural phase transitions common to other members of the isostructural family [(CH_{3})_{4}N][MX_{3}]. It is supposed to be related to the ordering of the organic part together with some small distortion of the inorganic chains. The origin of the order–disorder mechanism would be the orientationally disordered distribution of the tetramethylammonium tetrahedra at room temperature. Maximum Entropy Methods suggest that the most probable distribution of the organic groups can be described through the so-called two-well model, in which one threefold axis of the tetramethylammonium tetrahedron coincides with the crystallographic threefold axis of the structure. Below 118 K the reflections are split. However, the splitting cannot be fully explained by the ferroelastic domains expected to appear after the phase transitions. Recent NMR results [Mulla-Osman et al. (1998). J. Phys. Condensed Matter, 10, 2465–2476] corroborate the existence of more domains than expected from symmetry considerations. A model of ferroelastic domains which is in agreement with both X-ray diffraction diagram and NMR measurements is proposed.

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Journal articles on the topic 'Compound K-distribution'

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