Journal articles: 'Model buňky'

1

Tanaka, Kazuyoshi, Kenji Okahara, Mayumi Okada, and Tokio Yamabe. "Electronic properties of bucky-tube model." Chemical Physics Letters 191, no. 5 (April 1992): 469–72. http://dx.doi.org/10.1016/0009-2614(92)85410-c.

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Yamabe, Tokio, Kenji Okahara, Mayumi Okada, and Kazuyoshi Tanaka. "Electronic properties of bucky-tube model." Synthetic Metals 56, no. 2-3 (April 1993): 3142–47. http://dx.doi.org/10.1016/0379-6779(93)90093-c.

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3

Ghamsari, A. K., Y. Jin, E. Zegeye, and E. Woldesenbet. "Bucky gel actuator displacement: experiment and model." Smart Materials and Structures 22, no. 2 (January 28, 2013): 025034. http://dx.doi.org/10.1088/0964-1726/22/2/025034.

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Wrobel, Dominika, Radka Kubikova, Monika Müllerová, Tomas Strašák, Květoslav Růžička, Michal Fulem, and Jan Maly. "Phosphonium carbosilane dendrimers – interaction with a simple biological membrane model." Physical Chemistry Chemical Physics 20, no. 21 (2018): 14753–64. http://dx.doi.org/10.1039/c7cp07237f.

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Factors such as shielding of charge on dendrimers by bulky substituents and/or hydrophobicity of substituents are important for final ability of dendrimers to interact with and to penetrate deep into the lipid bilayer.

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Sharma, Mukesh C., and Smita Sharma. "Molecular Modeling Studies of Thiophenyl C-Aryl Glucoside SGLT2 Inhibitors as Potential Antidiabetic Agents." International Journal of Medicinal Chemistry 2014 (December 10, 2014): 1–15. http://dx.doi.org/10.1155/2014/739646.

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A QSAR study on thiophenyl derivatives as SGLT2 inhibitors as potential antidiabetic agents was performed with thirty-three compounds. Comparison of the obtained results indicated the superiority of the genetic algorithm over the simulated annealing and stepwise forward-backward variable method for feature selection. The best 2D QSAR model showed satisfactory statistical parameters for the data set (r2=0.8499, q2=0.8267, and pred_r2=0.7729) with four descriptors describing the nature of substituent groups and the environment of the substitution site. Evaluation of the model implied that electron-rich substitution position improves the inhibitory activity. The good predictive 3D-QSAR models by k-nearest neighbor (kNN) method for molecular field analysis (MFA) have cross-validated coefficient q2 value of 0.7663 and predicted r2 value of 0.7386. The results have showed that thiophenyl groups are necessary for activity and halogen, bulky, and less bulky groups in thiophenyl nucleus enhanced the biological activity. These studies are promising for the development of novel SGLT2 inhibitor, which may have potent antidiabetic activity.

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Ayub, Khurshid, and Ralf Ludwig. "Gas hydrates model for the mechanistic investigation of the Wittig reaction “on water”." RSC Adv. 6, no. 28 (2016): 23448–58. http://dx.doi.org/10.1039/c5ra25747f.

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Water in action! A gas hydrate model consisting of 20 water molecules nicely illustrates acceleration of cis-Wittig reaction over trans-Wittig reaction "on water". "Bucky" water is a perfect model for describing chemical reactions "on water".

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Leppin, Jana, Christoph Förster, and Katja Heinze. "Molybdenum Complex with Bulky Chelates as a Functional Model for Molybdenum Oxidases." Inorganic Chemistry 53, no. 23 (November 13, 2014): 12416–27. http://dx.doi.org/10.1021/ic501751p.

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Chan, C. L., and I. Shih. "Extended Goodman model for series resistance masking on bulky semiconductor junction capacitance." Journal of Applied Physics 67, no. 10 (May 15, 1990): 6544–47. http://dx.doi.org/10.1063/1.345132.

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Goy, Roman, Luca Bertini, Catherine Elleouet, Helmar Görls, Giuseppe Zampella, Jean Talarmin, Luca De Gioia, Philippe Schollhammer, Ulf-Peter Apfel, and Wolfgang Weigand. "A sterically stabilized FeI–FeI semi-rotated conformation of [FeFe] hydrogenase subsite model." Dalton Transactions 44, no. 4 (2015): 1690–99. http://dx.doi.org/10.1039/c4dt03223c.

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Semi-rotated state – As the first example so far a [Fe^IFe^I] H₂ase model complex with a bulky silicon-containing dithiolate bridge is reported showing a semi-rotated geometry without the need of stabilization via agostic interactions.

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Jiang, Shuang, Tianyong Zhang, Xia Zhang, Guanghui Zhang, Li Hai, and Bin Li. "Synthesis, structural characterization, and chemical properties of pentacoordinate model complexes for the active site of [Fe]-hydrogenase." RSC Advances 6, no. 87 (2016): 84139–48. http://dx.doi.org/10.1039/c6ra18628a.

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Four pentacoordinate iron dicarbonyl with bulky NHC ligands were synthesised as model of [Fe]-hydrogenase active site, which exhibited different protonation reactivity due to the variable electronic and steric effects of introduced ligands.

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Srivastava, Kinshuk Raj, Bhupesh Goyal, Anil Kumar, and Susheel Durani. "Scrutiny of electrostatic-driven conformational ordering of polypeptide chains in DMSO: a study with a model oligopeptide." RSC Advances 7, no. 45 (2017): 27981–91. http://dx.doi.org/10.1039/c7ra02137b.

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The molecular mechanism of DMSO-induced stabilisation of β-sheets is attributed to the combination of polar electrostatic interactions among side chains, and backbone desolvation through bulky side chains which promotes backbone hydrogen bonding.

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Dey, Subhayan, Daniel Buzsáki, Clemens Bruhn, Zsolt Kelemen, and Rudolf Pietschnig. "Bulky 1,1′-bisphosphanoferrocenes and their coordination behaviour towards Cu(i)." Dalton Transactions 49, no. 20 (2020): 6668–81. http://dx.doi.org/10.1039/d0dt00941e.

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Breckwoldt, Nicholas C. C., Neill J. Goosen, Hermanus C. M. Vosloo, and Percy Van der Gryp. "Kinetic evaluation of the hydroformylation of the post-metathesis product 7-tetradecene using a bulky phosphite-modified rhodium catalyst." Reaction Chemistry & Engineering 4, no. 4 (2019): 695–704. http://dx.doi.org/10.1039/c8re00239h.

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Hasenaka, Yuki, Taka-aki Okamura, and Kiyotaka Onitsuka. "Modeling of the hydrophobic microenvironment of water-soluble molybdoenzymes in an aqueous micellar solution." Dalton Transactions 44, no. 28 (2015): 12618–22. http://dx.doi.org/10.1039/c5dt01112d.

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15

Singleton, Michael L, Nattamai Bhuvanesh, Joseph H Reibenspies, and Marcetta Y Darensbourg. "Synthetic Support of De Novo Design: Sterically Bulky [FeFe]-Hydrogenase Models." Angewandte Chemie 120, no. 49 (November 24, 2008): 9634–37. http://dx.doi.org/10.1002/ange.200803939.

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Singleton, Michael L, Nattamai Bhuvanesh, Joseph H Reibenspies, and Marcetta Y Darensbourg. "Synthetic Support of De Novo Design: Sterically Bulky [FeFe]-Hydrogenase Models." Angewandte Chemie International Edition 47, no. 49 (November 24, 2008): 9492–95. http://dx.doi.org/10.1002/anie.200803939.

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17

Xu and Chung. "Quantitative Structure–Activity Relationship Study of Bitter Di-, Tri- and Tetrapeptides Using Integrated Descriptors." Molecules 24, no. 15 (August 5, 2019): 2846. http://dx.doi.org/10.3390/molecules24152846.

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New quantitative structure–activity relationship (QSAR) models for bitter peptides were built with integrated amino acid descriptors. Datasets contained 48 dipeptides, 52 tripeptides and 23 tetrapeptides with their reported bitter taste thresholds. Independent variables consisted of 14 amino acid descriptor sets. A bootstrapping soft shrinkage approach was utilized for variable selection. The importance of a variable was evaluated by both variable selecting frequency and standardized regression coefficient. Results indicated model qualities for di-, tri- and tetrapeptides with R2 and Q2 at 0.950 ± 0.002, 0.941 ± 0.001; 0.770 ± 0.006, 0.742 ± 0.004; and 0.972 ± 0.002, 0.956 ± 0.002, respectively. The hydrophobic C-terminal amino acid was the key determinant for bitterness in dipeptides, followed by the contribution of bulky hydrophobic N-terminal amino acids. For tripeptides, hydrophobicity of C-terminal amino acids and the electronic properties of the amino acids at the second position were important. For tetrapeptides, bulky hydrophobic amino acids at N-terminus, hydrophobicity and partial specific volume of amino acids at the second position, and the electronic properties of amino acids of the remaining two positions were critical. In summary, this study not only constructs reliable models for predicting the bitterness in different groups of peptides, but also facilitates better understanding of their structure-bitterness relationships and provides insights for their future studies.

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18

Pegg, GG, and GV Meehan. "Stereoselectivity of Sigmatropic Homodienyl [1,5]-Hydrogen Migrations." Australian Journal of Chemistry 43, no. 6 (1990): 1009. http://dx.doi.org/10.1071/ch9901009.

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Interactions affecting the transition state conformational preference of substituents (R1) at the migration origin have been extensively examined for a range of diversely substituted alkenylcyclopropane substrates undergoing homodienyl [1,5]-hydrogen migration. A chair cyclohexane -like transition state model (11) best rationalizes the stereoselectivity observed in these cases. Thus, the 1,2-double-bond (E)/(Z) ratio for the rearrangement products is in reasonable agreement with prediction based on ΔG° values for R1 equatorial/axial interconversion in substituted cyclohexanes (at least for cases where R3 = H). For systems incorporating a bulky R3 substituent, a marked increase in stereoselectivity for the (E)-olefin product is observed. In agreement with the proposed transition state model (11), bulky R2 or R4 substituents have negligible effect on the conformational preference of R1.

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19

Espinosa-Jalapa, Noel Angel, Nele Berg, Michael Seidl, Ilya G. Shenderovich, Ruth M. Gschwind, and Jonathan O. Bauer. "Complexation behaviour of LiCl and LiPF6 – model studies in the solid-state and in solution using a bidentate picolyl-based ligand." Chemical Communications 56, no. 87 (2020): 13335–38. http://dx.doi.org/10.1039/d0cc05682k.

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Using a new bulky bidentate ligand and combining various structure elucidation methods, coordination modes of [ligand·LiX] (X = Cl, PF₆) complexes both in solid-state and in solution have been revealed.

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20

Rafsanjani, Ahmad, Dominique Derome, and Jan Carmeliet. "Poromechanical modeling of moisture induced swelling anisotropy in cellular tissues of softwoods." RSC Advances 5, no. 5 (2015): 3560–66. http://dx.doi.org/10.1039/c4ra14074e.

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In cellular tissues of softwoods, the degree of swelling anisotropy in thin-walled earlywood cells is much larger than in bulky latewood cells. This behavior is simulated by means of a double porosity poromechanical model.

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21

Martínez-François, Juan Ramón, and Zhe Lu. "Intrinsic versus extrinsic voltage sensitivity of blocker interaction with an ion channel pore." Journal of General Physiology 135, no. 2 (January 25, 2010): 149–67. http://dx.doi.org/10.1085/jgp.200910324.

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Many physiological and synthetic agents act by occluding the ion conduction pore of ion channels. A hallmark of charged blockers is that their apparent affinity for the pore usually varies with membrane voltage. Two models have been proposed to explain this voltage sensitivity. One model assumes that the charged blocker itself directly senses the transmembrane electric field, i.e., that blocker binding is intrinsically voltage dependent. In the alternative model, the blocker does not directly interact with the electric field; instead, blocker binding acquires voltage dependence solely through the concurrent movement of permeant ions across the field. This latter model may better explain voltage dependence of channel block by large organic compounds that are too bulky to fit into the narrow (usually ion-selective) part of the pore where the electric field is steep. To date, no systematic investigation has been performed to distinguish between these voltage-dependent mechanisms of channel block. The most fundamental characteristic of the extrinsic mechanism, i.e., that block can be rendered voltage independent, remains to be established and formally analyzed for the case of organic blockers. Here, we observe that the voltage dependence of block of a cyclic nucleotide–gated channel by a series of intracellular quaternary ammonium blockers, which are too bulky to traverse the narrow ion selectivity filter, gradually vanishes with extreme depolarization, a predicted feature of the extrinsic voltage dependence model. In contrast, the voltage dependence of block by an amine blocker, which has a smaller “diameter” and can therefore penetrate into the selectivity filter, follows a Boltzmann function, a predicted feature of the intrinsic voltage dependence model. Additionally, a blocker generates (at least) two blocked states, which, if related serially, may preclude meaningful application of a commonly used approach for investigating channel gating, namely, inferring the properties of the activation gate from the kinetics of channel block.

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22

Espinosa, Felipe, Richard Fleischhauer, Anne McMahon, and Rolf H. Joho. "Dynamic Interaction of S5 and S6 during Voltage-Controlled Gating in a Potassium Channel." Journal of General Physiology 118, no. 2 (July 30, 2001): 157–70. http://dx.doi.org/10.1085/jgp.118.2.157.

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A gain-of-function mutation in the Caenorhabditis elegans exp-2 K+-channel gene is caused by a cysteine-to-tyrosine change (C480Y) in the sixth transmembrane segment of the channel (Davis, M.W., R. Fleischhauer, J.A. Dent, R.H. Joho, and L. Avery. 1999. Science. 286:2501–2504). In contrast to wild-type EXP-2 channels, homotetrameric C480Y mutant channels are open even at −160 mV, explaining the lethality of the homozygous mutant. We modeled the structure of EXP-2 on the 3-D scaffold of the K+ channel KcsA. In the C480Y mutant, tyrosine 480 protrudes from S6 to near S5, suggesting that the bulky side chain may provide steric hindrance to the rotation of S6 that has been proposed to accompany the open-closed state transitions (Perozo, E., D.M. Cortes, and L.G. Cuello. 1999. Science. 285:73–78). We tested the hypothesis that only small side chains at position 480 allow the channel to close, but that bulky side chains trap the channel in the open state. Mutants with small side chain substitutions (Gly and Ser) behave like wild type; in contrast, bulky side chain substitutions (Trp, Phe, Leu, Ile, Val, and His) generate channels that conduct K+ ions at potentials as negative as −120 mV. The side chain at position 480 in S6 in the pore model is close to and may interact with a conserved glycine (G421) in S5. Replacement of G421 with bulky side chains also leads to channels that are trapped in an active state, suggesting that S5 and S6 interact with each other during voltage-dependent open-closed state transitions, and that bulky side chains prevent the dynamic changes necessary for permanent channel closing. Single-channel recordings show that mutant channels open frequently at negative membrane potentials indicating that they fail to reach long-lasting, i.e., stable, closed states. Our data support a “two-gate model” with a pore gate responsible for the brief, voltage-independent openings and a separately located, voltage-activated gate (Liu, Y., and R.H. Joho. 1998. Pflügers Arch. 435:654–661).

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23

Luo, Yu-Ran, and Philip D. Pacey. "Generalization of an empirical model for bond dissociation energies." Canadian Journal of Chemistry 71, no. 4 (April 1, 1993): 572–77. http://dx.doi.org/10.1139/v93-079.

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A relationship between homolytic bond dissociation energies (BDEs) of C—X bonds and the electronegativity of X and the degree of methyl substitution of C has been extended. The range of leaving groups, X, now includes SiH3, GeH3, and PH2 and a variety of C-, N-, and O-centred radicals. Alkyl groups with ethyl and propyl chains attached to the radical centre have been incorporated. Steric effects, including those in bulky silanes, have been treated. The method is believed to be generally applicable where resonance and ring strain are not significant. BDEs for 73 bonds have been calculated; in the 42 cases where experimental data are available, the average deviation is 0.7 kcal/mol.

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Caruso, Ugo, Rosita Diana, Angela Tuzi, and Barbara Panunzi. "Novel Solid-State Emissive Polymers and Polymeric Blends from a T-Shaped Benzodifuran Scaffold: A Comparative Study." Polymers 12, no. 3 (March 24, 2020): 718. http://dx.doi.org/10.3390/polym12030718.

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Two novel polyimines were synthesized from a benzodifuran based diamino monomer and two dialdehydes bearing bulky groups and a flexible spacer. The polymers display tuned luminescence performance according to the presence of half-salen groups. The effect of the intramolecular bond on the emission properties were examined. Two model compounds, replicating the same emissive Schiff base cores, were synthetized. From the models, dye-doped blends in the fluorophore/matrix ratio, resembling the polymers, were produced. Amorphous thin films of the covalent polymers and the polymeric blends were obtained by spin-coating technique. The Photoluminescent (PL) response of the different macromolecular systems were qualitatively and quantitatively examined and compared.

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Ismailova, Nazaket. "Management of the Forest Soils Fertility Based on Ecological Models in the South-Eastern Part of the Great Caucasus." Natural Systems and Resources, no. 1 (October 2019): 5–10. http://dx.doi.org/10.15688/nsr.jvolsu.2019.1.1.

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The bloks which are a structural part of the ecological fertility model in the mountain-forest brown and mountain-forest brown soils on the south-eastern slope of the Great Caucasus besides an importance of the ecological models composition have been analyzed in the article. By the main purpose of the given investigations a creation of ecological models of fertility was mountain-forest brown soils (middle mountain broken) and mountainforest brown soils (low mountain (mean broken), interrelation and dependence of biocenosis condition on the environment factors are studied a role of the main parameters (climate, relief, soil and etc) is revealed, the real and optimal parameters of the environment are established for the ecological models blocks creation. The model consists of 7 (seven) blocks: agroecological block soil structure block, soil regimes block, soil features block. value block, agromelioration block and forests biometric block. During the model blocks compiling the main diagnostic indiced as a granulometric composition, humus quantity and supply, water suspension pH, NPK, bulky mass, porosity and water-stable aggregates (> 0,25mm and > 1,00mm) in the mountain-forest brown and mountain-forest brown soils have been taken into account. A comparative character of the ecological fertility models in two different soil types which are dominant in forest ecosystems has been given.

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Krynke, Marek, Ludwik Kania, and Eugeniusz Mazanek. "Modelling the Contact between the Rolling Elements and the Raceways of Bulky Slewing Bearings." Key Engineering Materials 490 (September 2011): 166–78. http://dx.doi.org/10.4028/www.scientific.net/kem.490.166.

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In slewing bearings, a great number of contact pairs are present on the contact surfaces between the rolling elements and raceways of the bearing. Computations to determine the load of the individual rolling elements, taking into account the flexibility of the bearing ring, are most often carried out using the finite element method. Construction of a FEM full model of the bearing, taking into account the shape of the rolling elements and the determination of the contact problem for every rolling element, leads to a singularity of stiffness matrix, which in turn makes the problem impossible to solve. In FEM models the rolling elements are replaced by one-dimensional finite elements (linear elements) to simplify the computation procedure and to obtain an optimal time for computations. The methods of modelling the rolling elements in the slewing bearing, in which balls have been replaced by truss elements with a material non-linear characteristic located between the raceway centres of the curvatures in their axial section, are presented in the paper.

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Wiatr, P., and A. Kryński. "Model predictive control of multilevel cascaded converter with boosting capability – experimental results." Bulletin of the Polish Academy of Sciences Technical Sciences 65, no. 5 (October 1, 2017): 589–99. http://dx.doi.org/10.1515/bpasts-2017-0064.

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Abstract The main goal of this paper is to present a five-level converter with the feature of output voltage boosting capability. Thanks to its modular construction and single DC source usage, 5LCHB converter becomes an important alternative for two-level converters operating with DC-DC converters that use bulky inductors. Furthermore, model predictive control (MPC) method is presented, which allows for boosting output voltage of presented converter while providing three-phase load current control and flying capacitor voltage stabilization. The last section describes a 5kVA laboratory model of five-level hybrid converter interfacing RL load and shows experimental results confirming theoretical analysis derived in previous sections.

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Medel, Robert, Matthias Heger, and Martin A. Suhm. "Molecular Docking via Olefinic OH···π Interactions: A Bulky Alkene Model System and Its Cooperativity." Journal of Physical Chemistry A 119, no. 9 (November 6, 2014): 1723–30. http://dx.doi.org/10.1021/jp508424p.

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29

van Beilen, Jan B., Theo H. M. Smits, Franz F. Roos, Tobias Brunner, Stefanie B. Balada, Martina Röthlisberger, and Bernard Witholt. "Identification of an Amino Acid Position That Determines the Substrate Range of Integral Membrane Alkane Hydroxylases." Journal of Bacteriology 187, no. 1 (January 1, 2005): 85–91. http://dx.doi.org/10.1128/jb.187.1.85-91.2005.

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ABSTRACT Selection experiments and protein engineering were used to identify an amino acid position in integral membrane alkane hydroxylases (AHs) that determines whether long-chain-length alkanes can be hydroxylated by these enzymes. First, substrate range mutants of the Pseudomonas putida GPo1 and Alcanivorax borkumensis AP1 medium-chain-length AHs were obtained by selection experiments with a specially constructed host. In all mutants able to oxidize alkanes longer than C13, W55 (in the case of P. putida AlkB) or W58 (in the case of A. borkumensis AlkB1) had changed to a much less bulky amino acid, usually serine or cysteine. The corresponding position in AHs from other bacteria that oxidize alkanes longer than C13 is occupied by a less bulky hydrophobic residue (A, V, L, or I). Site-directed mutagenesis of this position in the Mycobacterium tuberculosis H37Rv AH, which oxidizes C10 to C16 alkanes, to introduce more bulky amino acids changed the substrate range in the opposite direction; L69F and L69W mutants oxidized only C10 and C11 alkanes. Subsequent selection for growth on longer alkanes restored the leucine codon. A structure model of AHs based on these results is discussed.

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Weinberg, Benjamin Adam, Manel Rakez, Benoist Chibaudel, Tim Maughan, Richard Adams, John Raymond Zalcberg, Axel Grothey, et al. "Tumor bulk as a prognostic biomarker and predictor of benefit from anti-EGFR therapy in patients with metastatic colorectal cancer: Analysis of 476 patients from the ARCAD Clinical Trials Program." Journal of Clinical Oncology 39, no. 3_suppl (January 20, 2021): 108. http://dx.doi.org/10.1200/jco.2021.39.3_suppl.108.

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108 Background: Primary tumor sidedness has emerged as a prognostic and predictive biomarker for patients (pts) with metastatic colorectal cancer (mCRC). Tumor bulk has also been postulated to predict response to anti-EGFR therapy. We sought to evaluate the role of tumor bulk as a predictive biomarker to anti-EGFR therapy in pts with left- (LS) and right-sided (RS) mCRC. Methods: Data from 476 pts with mCRC enrolled across 2 first-line trials of anti-EGFR plus chemotherapy versus chemotherapy were pooled. Pts were included if there was available information on tumor sidedness and tumor bulk. All were KRAS wild-type and BRAF wild-type or unknown BRAF status. The right colon was defined as the cecum through the transverse colon, and the left colon as the splenic flexure through the rectum. Tumor bulk was the mean tumor size of target lesions at baseline, bulky defined as > 3.5 cm. Overall survival (OS) and progression-free survival (PFS) were assessed using Kaplan-Meier and Cox models adjusting for performance status (PS), platelet count, primary tumor (PT) resection, number of metastatic sites, and stratified by study. Results: Pts with bulky tumors (211, 44%) had higher PS, white blood cell and platelet counts, higher CEA, fewer sites of metastatic disease, more liver than lung metastases, and fewer had PT resection. OS and PFS medians in months (mos) are presented in the table with 95% confidence intervals (95%CIs). Bulky tumors had inferior median OS compared with non-bulky (mOS, 17.9 vs. 21.3 mos, HRadj 1.33, 95% CI 1.05-1.69, P = 0.016) although median PFS was similar (mPFS, 8.6 vs. 8.7 mos, HRadj 1.15, 95% CI 0.92-1.42, P = 0.21). Conclusions: Tumor bulk is an independent prognostic factor for OS in KRAS wild-type and BRAF wild-type or unknown BRAF status pts. Pts with non-bulky RS tumors have survival outcomes similar to pts with bulky LS tumors. Although the mPFS for pts with RS tumors treated with anti-EGFR therapy was the lowest across subgroups, this finding was not statistically significant. Further research is warranted into whether pts with bulky RS tumors benefit from anti-EGFR therapy. Clinical trial information: NCT00182715, NCT00640081. [Table: see text]

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Haller, Nicolas, Jacob Reiss, Frank Seipel, Robert Weishar, Zachary Alden, Tracy Jane Puccinelli, and Julie Walker. "Development of a Synthetic Training Model for Canine Thoracocentesis." Alternatives to Laboratory Animals 48, no. 2 (March 2020): 78–84. http://dx.doi.org/10.1177/0261192920924408.

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Thoracocentesis, a procedure in which air or fluid is removed from the pleural space, is used to relieve respiratory distress, and as a diagnostic procedure in human and veterinary medicine. Veterinary students commonly learn and practice the procedure on canine cadavers which are in limited supply and are not amenable to long-term storage and use. Practicing thoracocentesis on a cadaveric model also provides limited feedback indicative of success and/or procedural complications. One commercial model for practicing canine thoracocentesis is available, but it costs over US$2000 and is excessively bulky. In order to improve the learning process for veterinary students, we have developed a reusable synthetic canine thorax model that accurately replicates the thoracocentesis procedure, provides immediate feedback to the students and reduces the need for canine cadavers. The low cost of our product provides an efficient alternative to cadavers for instruction in veterinary schools or hospitals.

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Delos, Sue E., Bonnie La, Allissia Gilmartin, and Judith M. White. "Studies of the “Chain Reversal Regions” of the Avian Sarcoma/Leukosis Virus (ASLV) and Ebolavirus Fusion Proteins: Analogous Residues Are Important, and a His Residue Unique to EnvA Affects the pH Dependence of ASLV Entry." Journal of Virology 84, no. 11 (March 24, 2010): 5687–94. http://dx.doi.org/10.1128/jvi.02583-09.

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ABSTRACT Most class I fusion proteins exist as trimers of dimers composed of a receptor binding and a fusion subunit. In their postfusion forms, the three fusion subunits form trimers of hairpins consisting of a central coiled coil (formed by the N-terminal helices), an intervening sequence, and a region containing the C helix (and flanking strands) that runs antiparallel to and packs in the grooves of the N-terminal coiled coil. For filoviruses and most retroviruses, the intervening sequence includes a “chain reversal region” consisting of a short stretch of hydrophobic residues, a Gly-Gly pair, a CX6CC motif, and a bulky hydrophobic residue. Maerz and coworkers (A. L. Maerz, R. J. Center, B. E. Kemp, B. Kobe, and P. Poumbourios, J. Virol. 74:6614-6621, 2000) proposed a model for this region of human T-cell leukemia virus type 1 (HTLV-1) Env in which expulsion of the final bulky hydrophobic residue is important for early conformational changes and specific residues in the chain reversal region are important for forming the final, stable trimer of hairpins. Here, we used mutagenesis and pseudovirus entry assays to test this model for the avian retrovirus avian sarcoma/leukosis virus (ASLV) and the filovirus ebolavirus Zaire. Our results are generally consistent with the model proposed for HTLV-1 Env. In addition, we show with ASLV EnvA that the bulky hydrophobic residue following the CX6CC motif is required for the step of prehairpin target membrane insertion, whereas other residues are required for the foldback step of fusion. We further found that a His residue that is unique to the chain reversal region of ASLV EnvA controls the pH at which ASLV entry occurs.

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Randriamahazaka, Hyacinthe, and Kinji Asaka. "Strain–capacitance relationship in polymer actuators based on single-walled carbon nanotubes and ionic liquid gels." Faraday Discussions 199 (2017): 405–22. http://dx.doi.org/10.1039/c6fd00232c.

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We investigate the electromechanical properties of bucky-gel electrochemical actuators incorporating various amounts of single-walled carbon nanotubes and an ionic liquid electrolyte, 1-butyl-3-methylimidazolium tetrafluoroborate, that are able to convert electrochemical energy into mechanical energy. The interplay between mechanical and electrochemical effects is studied. The electromechanical responses are investigated by means of electrochemical impedance spectroscopy and bending displacement measurements. We develop a theoretical model that allows us to rationalize the electromechanical properties of the bucky-gel actuators. This model takes into account electrochemical stress due to the intercalation (de-intercalation) process, which generates the strain and bending of the actuators. We then analyze the relationship between the strain and the real part of the complex capacitance by introducing a strain–capacitance coefficient. This coefficient is related to the electrochemical stress and the amount of the ionic adsorption (desorption) at the double-layer. From a practical point of view, the determination of the strain–capacitance coefficient is helpful for characterizing and optimizing the performance of electrochemical actuators.

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Chi, D. S., Y. Sonoda, N. R. Abu-Rustum, C. S. Awtrey, J. Huh, R. R. Barakat, and M. W. Kattan. "Nomogram for survival after primary surgery for bulky stage IIIC ovarian carcinoma." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 5058. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.5058.

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5058 Background: Nomograms have been developed for numerous malignancies to predict a specific individual’s probability of long-term survival based on known prognostic factors. To date, no prediction model has been developed for patients with ovarian cancer. The objective of this study was to develop a nomogram to predict the probability of 4-year survival after primary cytoreductive surgery for bulky stage IIIC ovarian carcinoma. Methods: Nomogram predictor variables included age, tumor grade, histologic type, preoperative platelet count, the presence or absence of ascites, and residual disease status after primary cytoreduction. Disease-specific survival was estimated using the Kaplan-Meier method. Cox proportional hazards regression was used for multivariable analysis. The Cox model was the basis for the nomogram. The concordance index was used as an accuracy measure, with bootstrapping to correct for optimistic bias. Calibration plots were constructed. Results: A total of 462patients with bulky stage IIIC ovarian carcinoma underwent primary cytoreductive surgery at our institution during the study period of 1/89 to 12/03, of whom 397 were evaluable for inclusion in the study. The median age of the study population was 60 years (range 22–87). The primary surgeon in all cases was an attending gynecologic oncologist. Postoperatively, all patients received platinum-based systemic chemotherapy. Ovarian cancer-specific survival at 4 years was 51%. A nomogram was constructed on the basis of a Cox regression model and the 6 predictor variables. This nomogram was internally validated using bootstrapping and shown to have excellent calibration with a bootstrap-corrected concordance index of 0.67. Conclusions: A nomogram was developed to predict 4-year disease-specific survival after primary cytoreductive surgery for bulky stage IIIC ovarian carcinoma. The nomogram utilizes 6 predictor variables that are readily accessible, assigns a point value to each variable, and then predicts the probability of 4-year survival based on the total point value for an individual patient. This tool should be useful for patient counseling, clinical trial eligibility determination, postoperative management, and follow-up. No significant financial relationships to disclose.

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Wiatr, P., and M. P. Kazmierkowski. "Model predictive control of multilevel cascaded converter with boosting capability – a simulation study." Bulletin of the Polish Academy of Sciences Technical Sciences 64, no. 3 (September 1, 2016): 581–90. http://dx.doi.org/10.1515/bpasts-2016-0065.

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Abstract This paper presents a multilevel cascaded H-bridge 5-level converter with boosting capability. The standard solution for boosting voltage in power electronic devices is based on a DC-DC converter with a bulky inductor. However, inductor is a problematic component of a power electronic converter because usually it has to be individually designed and produced for every device and also because its size and weight do not allow for compact construction. This paper presents model predictive control (MPC) method that gives boosting capability for the presented converter. A novel contribution of this paper is the development of a predictive model of the converter and cost function enabling output current control and capacitor voltage balancing.

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Wefel, J. S., and M. E. Jensen. "An Intra-oral Single-section Demineralization/Remineralization Model." Journal of Dental Research 71, no. 3_suppl (April 1992): 860–63. http://dx.doi.org/10.1177/002203459207100s14.

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This paper reviews the use of our intra-oral crown single-section model for the evaluation of in situ demineralization and remineralization. The model uses normal, healthy adults who are in need of a gold crown. A slot is placed in the working crown which can hold 3–4 single sections. A typical experiment would use an enamel lesion, root lesion, and sound root section which are characterized with polarized light microscopy and/or microradiography prior to insertion in the crown. After the experimental regimen, the sections are removed and re-characterized for any changes. The model has been used to evaluate mineral changes from the use of fluoride dentifrices and rinses, chewing gum, and food sequencing. The advantages of the model system are the before-and-after measurements on the same section, a natural plaque formation, interaction with saliva, episodic demineralization and remineralization, no bulky appliances, and the use of reasonable time frames. This model, therefore, reduces the artificiality of the in situ study to a great extent and appears to be a useful predictor of demineralization/remineralization interactions.

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Nolan, Michael W., Tracy L. Gieger, Alexander A. Karakashian, Mariana N. Nikolova-Karakashian, Lysa P. Posner, Donald M. Roback, Judith N. Rivera, and Sha Chang. "Outcomes of Spatially Fractionated Radiotherapy (GRID) for Bulky Soft Tissue Sarcomas in a Large Animal Model." Technology in Cancer Research & Treatment 16, no. 3 (February 7, 2017): 357–65. http://dx.doi.org/10.1177/1533034617690980.

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GRID directs alternating regions of high- and low-dose radiation at tumors. A large animal model mimicking the geometries of human treatments is needed to complement existing rodent systems (eg, microbeam) and clarify the physical and biological attributes of GRID. A pilot study was undertaken in pet dogs with spontaneous soft tissue sarcomas to characterize responses to GRID. Subjects were treated with either 20 Gy (3 dogs) or 25 Gy (3 dogs), delivered using 6 MV X-rays and a commercial GRID collimator. Acute toxicity and tumor responses were assessed 2, 4, and 6 weeks later. Acute Radiation Therapy Oncology Group grade I skin toxicity was observed in 3 of the 6 dogs; none experienced a measurable response, per Response Evaluation Criteria in Solid Tumors. Serum vascular endothelial growth factor, tumor necrosis factor α, and secretory sphingomyelinase were assayed at baseline, 1, 4, 24, and 48 hours after treatment. There was a trend toward platelet-corrected serum vascular endothelial growth factor concentration being lower 1 and 48 hours after GRID than at baseline. There was a significant decrease in secretory sphingomyelinase activity 48 hours after 25 Gy GRID ( P = .03). Serum tumor necrosis factor α was quantified measurable at baseline in 4 of the 6 dogs and decreased in each of those subjects at all post-GRID time points. The new information generated by this study includes the observation that high-dose, single fraction application of GRID does not induce measurable reduction in volume of canine soft tissue sarcomas. In contrast to previously published data, these data suggest that GRID may be associated with at least short-term reduction in serum concentration of vascular endothelial growth factor and serum activity of secretory sphingomyelinase. Because GRID can be applied safely, and these tumors can be subsequently surgically resected as part of routine veterinary care, pet dogs with sarcomas are an appealing model for studying the radiobiologic responses to spatially fractionated radiotherapy.

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Leuven, R. S. E. W., and F. H. G. Willems. "Cumulative metal leaching from utilisation of secondary building materials in river engineering." Water Science and Technology 49, no. 3 (February 1, 2004): 197–203. http://dx.doi.org/10.2166/wst.2004.0195.

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The present paper estimates the utilisation of bulky wastes (minestone, steel slag, phosphorus slag and demolition waste) in hydraulic engineering structures in Dutch parts of the rivers Rhine, Meuse and Scheldt over the period 1980-2025. Although they offer several economic, technical and environmental benefits, these secondary building materials contain various metals that may leach into river water. A leaching model was used to predict annual emissions of arsenic, cadmium, copper, chromium, lead, mercury, nickel and zinc. Under the current utilisation and model assumptions, the contribution of secondary building materials to metal pollution in Dutch surface waters is expected to be relatively low compared to other sources (less than 0.1% and 0.2% in the years 2000 and 2025, respectively). However, continued and widespread large-scale applications of secondary building materials will increase pollutant leaching and may require further cuts to be made in emissions from other sources to meet emission reduction targets and water quality standards. It is recommended to validate available leaching models under various field conditions. Complete registration of secondary building materials will be required to improve input data for leaching models.

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Petroka, R. P., and Liang-Wey Chang. "Experimental Validation of a Dynamic Model (Equivalent Rigid Link System) on a Single-Link Flexible Manipulator." Journal of Dynamic Systems, Measurement, and Control 111, no. 4 (December 1, 1989): 667–72. http://dx.doi.org/10.1115/1.3153111.

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Flexibility effects on robot manipulator design and control are typically ignored which is justified when large, bulky robotic mechanisms are moved at slow speeds. However, when increased speed and improved accuracy are desired in robot system performance it is necessary to consider flexible manipulators. This paper simulates the motion of a single-link, flexible manipulator using the Equivalent Rigid Link System (ERLS) dynamic model and experimentally validates the computer simulation results. Validation of the flexible manipulator dynamic model is necessary to ensure confidence of the model for use in future design and control applications of flexible manipulators.

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Pfreundschuh, Michael, Marita Ziepert, Marcel Reiser, Viola Poeschel, Sibylla Wilhelm, Tobias Gaska, Michael Heike, et al. "The Role of Radiotherapy to Bulky Disease in the Rituximab Era: Results from Two Prospective Trials of the German High-Grade Non-Hodgkin- Lymphoma Study Group (DSHNHL) for Elderly Patients with DLBCL." Blood 112, no. 11 (November 16, 2008): 584. http://dx.doi.org/10.1182/blood.v112.11.584.584.

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Abstract Background: The RICOVER60 trial has shown that 6 cycles of CHOP-14 with 8 applications of rituximab (6xR-CHOP-14) was superior to 8xR-CHOP-14, 6xCHOP-14 and 8xCHOP-14 in elderly patients with CD20-positive aggressive lymphoma. In that trial 117/306 (36%) of the patients in the 6xR-CHOP-14 arm were assigned to receive additional radiotherapy (Rx) to bulky disease (Pfreundschuh et al., Lancet Oncol. 2008). To study the relevance of additional Rx to bulky disease we subsequently initiated a prospective study in which no Rx was planned after 6 × R-CHOP-14. Methods: 166 elderly patients - subjected to the same inclusion and exclusion criteria as in the RICOVER-60 (R-CHOP-Rx) trial - were recruited for this study to receive 6xR-CHOP-14 without any radiotherapy (R-CHOP-noRx). The outcome of these patients was compared with the 306 patients assigned to receive 6xR-CHOP-14 and radiotherapy to bulky disease (³7.5 cm) in the R-CHOP-Rx trial. Results: 164/166 R-CHOP-noRx patients are evaluable with a median observation time of 17 months. Patients from both studies were well balanced for many known prognostic factors, but patients in R-CHOP-noRx were older (71 vs. 69 years; p=0.018), more frequently in advanced stages (60% vs. 50%; p=0.037), and with extranodal involvement (63% vs. 53%; p=0.024), while bulky disease was more frequent in the R-CHOP-Rx study (38% vs. 29%; p=0.038). Adherence to the immuno-chemotherapy protocol was excellent in both studies with median relative rituximab and cytotoxic drug doses of 99%. Overall response to therapy was similar in the two studies: CR/CRu: 76% vs. 78%; progressions 5.5% vs. 6.5%; relapses after CR/CRu 8% vs.10%; therapy-associated deaths 7% vs. 6% in R-CHOP-noRx and R-CHOP-Rx, respectively. Similarly, there were no significant differences between the two studies with respect to EFS, PFS and OS. This also holds in multivariate models adjusting for the prognostic imbalances between the cohorts. However, the patients with bulky disease in the R-CHOP-Rx trial assigned to receive additional radiotherapy to bulky disease had a 25% better 18-month EFS (68% [95%-CI: 59–76] vs. 43% [29–58]; p=0.002), a 10% better PFS (77% [70–85] vs. 67% [52–82]; p=0.123), and a 4% better OS (80% [72–87] vs. 76% [63–90]; p=0.509) compared with R-CHOP-noRx. The lower EFS rate in the R-CHOP-noRx study was due to patients with bulky disease not achieving CR or CRu after 6xRCHOP, while patients with bulky disease in CR or CRu after 6xR-CHOP-14 fared equally well with and without additional radiotherapy (18-month-EFS: 84% vs. 86%; p=0.512). Conclusion: In the rituximab era additional radiotherapy to bulky disease has no role for elderly patients in CR/CRu after completion of 6xR-CHOP-14 immunochemotherapy, but (unlike 2 additional chemotherapy cycles in the 8xR-CHOP-14 arm of R-CHOP-Rx) appears to be beneficial for patients with bulky disease achieving a PR.

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Shevchuk, T. M., M. A. Bordyuk, V. V. Krivtsov, V. V. Kukla, and V. A. Mashchenko. "Viscoelastic Properties of Filled Polyurethane Auxetics." Physics and Chemistry of Solid State 22, no. 2 (June 16, 2021): 328–35. http://dx.doi.org/10.15330/pcss.22.2.328-335.

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The paper presents experimental values of lateral and extension transmission ultrasonic waves speed and their absorbance coefficient obtained with the help of discrete immersed method in metal filled polymer auxetic samples with polyurethane matrix. Poisson’s ratio, real and imaginary parts of complex dynamic elastic modulus (Young’s modulus, shear modulus, bulk modulus) and mechanical losses tangent of angle for extension, lateral and bulk deformation have been calculated regarding paper’s results. Viscoelastic properties of polyurethane auxetic have been examined regarding different theoretical approaches. To support negative values of Poisson’s ratio, a filled polymer model with critical filler amount and auxetic deformation models have been used. Models structural characteristics for filled polyurethane auxetics have been defined. Systems modeling with solid bulky inclusions, that are able to absorb and to disseminate ultrasonic waves, enables to consider suchlike systems as complex density materials. It is shown that in certain ratio of wave parameters and environment structural and mechanical properties, resonance effects take place, regarding filler’s particles vibration as inclusions in general.

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Causo, Albert, Etsuko Ueda, Kentaro Takemura, Yoshio Matsumoto, Jun Takamatsu, and Tsukasa Ogasawara. "User-Adaptable Hand Pose Estimation Technique for Human-Robot Interaction." Journal of Robotics and Mechatronics 21, no. 6 (December 20, 2009): 739–48. http://dx.doi.org/10.20965/jrm.2009.p0739.

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Hand pose estimation using a multi-camera system allows natural non-contact interfacing unlike when using bulky data gloves. To enable any user to use the system regardless of gender or physical differences such as hand size, we propose hand model individualization using only multiple cameras. From the calibration motion, our method estimates the finger link lengths as well as the hand shape by minimizing the gap between the hand model and observation. We confirmed the feasibility of our proposal by comparing 1) actual and estimated link lengths and 2) hand pose estimation results using our calibrated hand model, a prior hand model and data obtained from data glove measurements.

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Holland, Patrick L. "Low-coordinate iron complexes as synthetic models of nitrogenase." Canadian Journal of Chemistry 83, no. 4 (April 1, 2005): 296–301. http://dx.doi.org/10.1139/v05-005.

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Three-coordinate iron sites are potentially important intermediates in the reduction of dinitrogen by the enzyme nitrogenase, but synthetic work to outline the behavior of three-coordinate iron complexes is in its infancy. Recent work shows that bulky diketiminate ligands give a general route to three-coordinate iron complexes with a variety of third ligands. The low coordination number leads to exciting new reactions in which NN bonds are weakened or broken. Such complexes show great promise for evaluating the ability of low-coordinate iron to perform bond cleavage reactions akin to the individual steps of the nitrogenase system.Key words: nitrogenase, three-coordinate iron, diketiminate, NN cleavage.

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Dickson, M. R. "A Working Model of a Fully Digital Academic High-Throughput Microscopy Facility." Microscopy and Microanalysis 4, S2 (July 1998): 72–73. http://dx.doi.org/10.1017/s1431927600020481.

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The Electron Microscope Unit at the University has a good selection of microscopes: two tungsten SEMs, two FESEMs, a microprobe analysis system, a 125 kY TEM, a 200 kV TEM, an AFM, an FIB miller, a Zeiss Photomicroscope and a Leica Macroscope. We service around 300 clients’ projects a year in every field of experimental science and engineering, logging over 8,000 hrs of beam time annually.But funding constraints have always kept us short staffed and our laboratory has been working towards complete digital image capture for the past ten years to enhance our productivity. The perceived benefits of digitisation for us are:Photographic processing of negatives eliminated.Archiving of (bulky) photographic negatives eliminated.Need for special darkroom & graphics skills eliminatedResponsibility for archiving and indexing images devolved to individual usersResponsibility for image processing devolved to individual users.Rapid turnaround of images.Rapid sharing of results.

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Cortelazzo, Sergio, Stefano Luminari, Monica Bellei, Maurizio Martelli, Umberto Vitolo, Luigi Rigacci, Achille Ambrosetti, et al. "A Predictive Model for Limited Stage Diffuse Large B-Cell Lymphoma (DLBCL): A Retrospective Analysis of 1,252 Cases Performed by the Intergruppo Italiano Linfomi (IIL)." Blood 104, no. 11 (November 16, 2004): 3261. http://dx.doi.org/10.1182/blood.v104.11.3261.3261.

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Abstract Introduction: few studies have explored the usefulness of a prognostic index specifically devised for patients with localized DLBCL. The IIL has performed a retrospective analysis of a large group of patients with limited stage DLBCL and developed a new prognostic model. Results: 1,252 patients with localized (Ann Arbor stage I-II) aggressive B-cell lymphoma (IWF: G or H, WHO:DLBCL) diagnosed from 1988 to 2002 and without CNS involvement, treated by 4 cooperative groups and 2 single institutions, are the subject of this analysis. Patient’s median age was 57 years (range, 17–91) and M/F ratio was 1.26. Clinical stage was I in 239 (19%), IE in 303 (24%), II in 356 (28%) and IIE in 354 (28%) patients, respectively. Supradiaphragmatic disease was present in 56% of patients, 13% had > 3 nodal sites, 53% had extranodal involvement, and 7% had >1 extranodal site. Bulky disease (≥10 cm) was present in 26% of patients, ECOG-PS >1 in 12% and B symptoms in 14%. Abnormal biochemical data included: elevated LDH (28%), β2-microglobulin (B2M;19%) and ESR (38%) and reduced albumin (< 3.5 g/dL) in 21% of the cases. Patients were treated with anthracyclin-containing regimens ± IF-RT. After a median follow-up of 62 months for alive patients (range 1–183 months), 3 and 5-year OS rates were 73% and 71%, respectively. By univariate analysis the following 11 variables were found to be predictive of a short survival: age ≥65 yrs (P=0,0001), stage II nodal (P=0,0001), number of nodal sites (P<0.0001), poor ECOG-PS (P<0.0001), B symptoms (P=0.0009), bulky disease (P=0.0001), elevated ESR (P=0.0001), LDH (P<0.0001), Radiotherapy (P<0.001), B2M (P=0.007) and reduced serum albumin (<0.0001). By Cox multivariate analysis, age ≥65 years (p<0.001), stage II nodal (P<0.001), high LDH (P<0.001) and bulky disease (P<0.01) were indipendent risk factors (RF) for a short survival. The prognostic model was calculated with the sum of scores assigned to each variable; a score of 2 was assigned to advanced age, high LDH, and Bulky; for Stage a score of 1 was considered for stage Ie-IIe and 2 for stage II nodal. Three groups of patients with a different probability of survival (P<0.000001) were identified. Patients at low (Score 0–1; 387 pts), intermediate (Score 2–3; 484 pts) or high risk (Score 4–8; 381 pts) had a 5 years OS of 87%, 77%, 51% respectively. The predictive performance of the model was internally validated through a non parametric Bootstrap method and through residues’ analysis. Conclusions: This prognostic model, developed and validated on a very large series of patients with localized DLBCL, will allow us to select appropriate therapeutic approaches on the basis of different risk categories.

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Cavanagh, Katie L., Stephen A. Glover, Helen L. Price, and Rhiannon R. Schumacher. "SN2 Substitution Reactions at the Amide Nitrogen in the Anomeric Mutagens, N-Acyloxy-N-alkoxyamides." Australian Journal of Chemistry 62, no. 7 (2009): 700. http://dx.doi.org/10.1071/ch09166.

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N-Acyloxy-N-alkoxyamides 1a are unusual anomeric amides that are pyramidal at the nitrogen because of bis oxyl substitution. Through this configuration, they lose most of their amide character and resemble α-haloketones in reactivity. They are susceptible to SN2 reactions at nitrogen, a process that is responsible for their mutagenic behaviour. Kinetic studies have been carried out with the nucleophile N-methylaniline that show that, like SN2 reactions at carbon centres, the rate constant for SN2 displacement of carboxylate is lowered by branching β to the nitrogen centre, or bulky groups on the alkoxyl side chain. Branching or bulky groups on the carboxylate leaving group, however, do not impact on the rate of substitution, which is mostly controlled by the pKA of the departing carboxylate group. These results are in line with computed properties for the model reaction of ammonia with N-acetoxy-N-methoxyacetamide but are in contrast to the role of steric effects on their mutagenicity.

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Zhuang, Ze-Peng, Rui Chen, Zhi-Bin Fan, Xiao-Ning Pang, and Jian-Wen Dong. "High focusing efficiency in subdiffraction focusing metalens." Nanophotonics 8, no. 7 (June 22, 2019): 1279–89. http://dx.doi.org/10.1515/nanoph-2019-0115.

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AbstractVector beams with phase modulation in a high numerical aperture system are able to break through the diffraction limit. However, the implementation of such a device requires a combination of several discrete bulky optical elements, increasing its complexity and possibility of the optical loss. Dielectric metalens, an ultrathin and planar nanostructure, has a potential to replace bulky optical elements, but its optimization with full-wave simulations is time-consuming. In this paper, an accurate and efficient theoretical model of planar metalens is developed. Based on this model, a twofold optimization scheme is proposed for optimizing the phase profile of metalenses so as to achieve subdiffraction focusing with high focusing efficiency. Then, a metalens that enables to simultaneously generate radially polarized beam (RPB) and modulate its phase under the incidence of x-polarized light with the wavelength of 532 nm is designed. Full-wave simulations show that the designed metalens of NA = 0.95 can achieve subdiffraction focusing (FWHM = 0.429λ) with high transmission efficiency (77.6%) and focusing efficiency (17.2%). Additionally, superoscillation phenomenon is found, leading to a compromise between the subdiffraction spot and high efficiency. The proposed method may provide an accurate and efficient way to achieve sub-wavelength imaging with the expected performances, which shows a potential application in super-resolution imaging.

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Gros, A., K. Jacquot, and T. Messaoudi. "KNOWLEDGE-BASED FRAMEWORK FOR AUTOMATIC SEMANTISATION AND RECONSTRUCTION OF MILITARY ARCHITECTURE ON CITY-SCALE MODELS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W9 (January 31, 2019): 369–75. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w9-369-2019.

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Abstract. The scale models of fortified towns belonging to the Plans-Reliefs collection are exceptional witnesses of the formation of the French territory. The aim of the URBANIA project is the valorisation and the diffusion of this heritage through the creation of virtual models. The town scale model of Strasbourg at 1:600 currently exhibited in the Historical Museum of Strasbourg was selected as a case study. We develop and experiment an automatic procedure to identify and reconstruct military architecture works from point cloud digitisation of this fragile and bulky heritage. A priori knowledge formalized in a domain ontology informs the identification of the works &ndash; via geometrical feature comparison and consistency evaluation within the fortification system morphology &ndash; and their parametric 3D reconstruction refined by direct fit to the initial point cloud.

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O'Brien, Susan, Samantha Jaglowski, John C. Byrd, Rajat Bannerji, Kristie Blum, Christopher P. Fox, Richard R. Furman, et al. "Analysis of Prognostic Factors Predictive of Complete Response (CR) to Ibrutinib in Patients with CLL/SLL." Blood 126, no. 23 (December 3, 2015): 4153. http://dx.doi.org/10.1182/blood.v126.23.4153.4153.

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Abstract Introduction: Chronic lymphocytic leukemia (CLL) has a heterogeneous clinical course, with many patients (pts) experiencing relapse after initial treatment. Ibrutinib is a first-in-class once-daily, oral, inhibitor of Bruton's tyrosine kinase indicated for treatment of pts with CLL with ≥1 prior therapy and for pts with 17p deletion CLL. Extended follow-up of ibrutinib-treated pts has demonstrated an increase in complete response (CR) rate over time (Byrd, Blood 2015; Brown, Blood 2015). This ad hoc analysis examines baseline factors predictive of CR in pts with CLL/SLL treated with ibrutinib. Methods: Univariate and multivariate analyses were performed on pooled data from studies of pts treated with either single-agent ibrutinib (PCYC-1102, PCYC-1112), or in combination with ofatumumab (PCYC-1109), to assess the prognostic value of various baseline factors on a CR to ibrutinib treatment in CLL/SLL. CR criteria were met per iwCLL parameters, including bone marrow confirmation, which was not mandated at any standard timepoint in any protocol. Both treatment-naive (TN) and previously treated (R/R) pts were included. Factors with P<0.15 in a univariate model were tested in a stepwise-selection logistic regression model. The multivariate model selected prognostic factors with P<0.05. Results: Data from 398 pts with TN or R/R CLL/SLL were analyzed. Patients had a median age of 67 years (range, 30-86 years). At baseline, 238 (60%) pts had bulky disease ≥5 cm, 227 (57%) were Rai stage III-IV, and 230 (58%) had ECOG ≥1 status. At baseline 121 (30%) pts had del11q, 127 (32%) del17p, 242 (61%) unmutated IGHV, and 230 (58%) β-2-microglobulin levels ≥3.5 mg/L. A total of 31 (8%) pts were TN, with 38 (10%) having 1, 106 (27%) having 2, and 223 (56%) having had ≥3 prior lines of therapy, with a median of 3 prior therapies for R/R pts. Univariate analysis of prognostic factors showed that bulky disease, Rai stage at baseline, number of prior therapies, and β2-microglobulin levels at baseline had a significant effect on the odds of CR. The final multivariate model selected showed a significant effect for TN over R/R, and for bulky disease (<5 cm) (Table). The odds of a CR increased for TN pts vs. pts with ≥1 prior therapy (OR = 2.56, P =0.0488), while the odds of a CR increased without bulky disease (<5 cm vs. ≥5 cm [OR = 5.03, P=0.0002]). Univariate analysis excluding TN pts showed that bulky disease (<5 cm vs. ≥5 cm) and β2-microglobulin levels (≤3.5 vs. ≥3.5 mg/L) were the only baseline factors with significant effect on the odds of a CR (P=0.0001 and P=0.009, respectively). The final multivariate model for the R/R population selected only bulky disease as a significant factor (P=0.0001). The majority of pts for the R/R analysis received ibrutinib as third-line (29%) or beyond (61%), while 10% received ibrutinib after only 1 prior therapy. Of all pts treated with ibrutinib, 35/398 (9%) had a CR (PCYC-1102: R/R 12/101 [12%], TN 8/31 [26%]; PCYC-1109: 3/71 [4.2%]; PCYC-1112: 12/195 [6.2%]). 62% of all pts met iwCLL CR criteria for all hematological parameters (platelet, hemoglobin, ANC, and ALC), some pending bone marrow confirmation of CR. Median duration of response for all responders was not reached. The median time to CR among 35 CR pts was 13.7 months. The median time to first response (partial response with lymphocytosis [PR-L] or better) was 2.5 months. Conclusions: Initial response to ibrutinib is achieved early, but the median time to CR is over one year. The rate of CR reported here with longer-term ibrutinib treatment is higher than in earlier reports (Byrd 2013, O'Brien 2014). Patients with treatment naive CLL and those without bulky lymphadenopathy have better odds of attaining a CR to treatment with ibrutinib. Table. Analysis of baseline prognostic factors for all pts Prognostic factors Baseline factor effect Odds Ratio P-value Univariate model ibrutinib vs. ibrutinib+anti-CD20 mAb 2.46 0.1459 <65 vs. ≥65 years 0.90 0.7816 Male vs. female 1.85 0.1578 ECOG 0 vs. >1 1.71 0.1334 Del11q negative vs. positive 1.05 0.9007 Del17p negative vs. positive 1.86 0.1569 IGHV mutated vs. unmutated 0.43 0.1268 Rai stage 0-II vs. III-IV 2.30 0.0251 Bulky disease <5 cm vs. ≥5 cm 5.84 <0.0001 Number of prior lines (0-1, 2, ≥3)0-1 vs. 20-1 vs. 30 vs. ≥10 vs. ≥2 -0.611.493.544.384.42 0.00470.04810.04810.00120.0053 β2M <3.5 vs. ≥3.5 mg/L 3.05 0.0035 Multivariate model Bulky disease <5 cm vs. ≥5 cm 5.03 0.0002 Prior lines 0 vs. ≥1 2.56 0.0488 Disclosures O'Brien: Pharmacyclics LLC, an AbbVie Company: Honoraria, Research Funding. Off Label Use: yes, discussion of ibrutinib in treatment naïve CLL. Jaglowski:Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; Seattle Genetics: Consultancy; Immunomedics: Research Funding. Byrd:Acerta Pharma BV: Research Funding. Bannerji:MedImmune: Research Funding; Regeneron: Research Funding; Gilead: Research Funding; AbbVie: Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; Merck: Patents & Royalties. Blum:Constellation Pharmaceuticals: Research Funding; Morphosys: Research Funding; Gilead: Research Funding; Millenium: Research Funding; Seattle Genetics: Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; Janssen: Research Funding; Novartis: Research Funding; Celgene: Research Funding. Fox:Janssen: Honoraria; Roche: Consultancy, Honoraria; Adienne: Consultancy, Other: Travel, Accommodations, Expenses, Research Funding; Gilead: Consultancy, Other: Travel, Accommodations, Expenses, Speakers Bureau; NAPP: Consultancy; Takeda Oncology: Honoraria, Other: Travel, Accommodations, Expenses. Hillmen:AbbVie: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Gilead: Consultancy, Honoraria, Research Funding; Novartis: Honoraria, Research Funding; GSK: Consultancy, Honoraria, Research Funding; Roche: Consultancy, Honoraria, Research Funding; Celgene: Research Funding. Kipps:Gilead: Consultancy; Genentech: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding. Montillo:Janssen: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Infinity: Research Funding; AbbVie: Research Funding; Gilead: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; Roche: Honoraria, Research Funding, Speakers Bureau; GSK: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses, Speakers Bureau. Sharman:Gilead: Research Funding, Speakers Bureau; Janssen: Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Honoraria, Research Funding. Suzuki:Pharmacyclics LLC, an AbbVie Company: Employment. James:Pharmacyclics LLC, an AbbVie Company: Employment. Chu:Pharmacyclics LLC, an AbbVie Company: Employment. Coutre:Janssen: Consultancy; Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; AbbVie: Research Funding.

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Pavkin, D. Yu, E. A. Nikitin, and V. A. Zobov. "Robotic System for Maintenance of Feed Table for Livestock Complexes." Agricultural Machinery and Technologies 14, no. 3 (September 25, 2020): 33–38. http://dx.doi.org/10.22314/2073-7599-2020-14-3-33-38.

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Abstract:

Assessing the robotization level of technological processes in livestock complexes based on the breeding, authors found that the most free niche of robotization of technological processes in livestock complexes is the feeding process, which forms 55 percent of milk productivity. There is a need to develop a wheeled robotic platform that will ensure the availability of the feed mixture along the feeding front. This platform will multi-stage saturate the bulky components of the feed mixture with concentrated ones, increasing their attractiveness to animals, while normalizing the balance of dry matter consumed and fiber obtained from bulky feeds.(Research purpose) To simulate the control system of a robotic platform with an independent electro- motorized drive.(Materials and methods) The article presents technologies for organizing animal feeding processes on the farm, conducted a technological assessment of the effectiveness of automated and robotic machines used on the farm. Authors used the Matlab/Simulink simulation environment in the research process.(Results and discussion) The article presents a developed mathematical model describing the kinematics and dynamics of the platform movement. Authors formed the assumed element base into a general model of the robot in an artificial Matlab/Simulink environment, simulating the process of moving around a circle.(Conclusions) The created mathematical model forms the basis for creating a control system for the robot under development. The device for dosing feed additives will ensure the balance of dry matter and fiber consumed.

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Journal articles on the topic 'Model buňky'

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