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Littérature scientifique sur le sujet « D-Complex Structures »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 11 mars 2023

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Articles de revues sur le sujet "D-Complex Structures"

Ciampolini, P., A. Pierantoni, and G. Baccarani. "Efficient 3-D simulation of complex structures." IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems 10, no. 9 (1991): 1141–49. http://dx.doi.org/10.1109/43.85760.

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Kado, Y., K. Aritake, N. Uodome, et al. "Human hematopoietic prostaglandin D synthase inhibitor complex structures." Journal of Biochemistry 151, no. 4 (2012): 447–55. http://dx.doi.org/10.1093/jb/mvs024.

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Hu, Chun-guang, Xiao-dong Hu, Lin-yan Xu, Tong Guo, and Xiao-tang Hu. "3-D profile measurement for complex micro-structures." Optoelectronics Letters 1, no. 3 (2005): 205–8. http://dx.doi.org/10.1007/bf03033844.

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Hassan, S. F. "O(d,d;R) deformations of complex structures and extended worldsheet supersymmetry." Nuclear Physics B 454, no. 1-2 (1995): 86–102. http://dx.doi.org/10.1016/0550-3213(95)00384-5.

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Yoon, Y. K., J. H. Park, and M. G. Allen. "Multidirectional UV Lithography for Complex 3-D MEMS Structures." Journal of Microelectromechanical Systems 15, no. 5 (2006): 1121–30. http://dx.doi.org/10.1109/jmems.2006.879669.

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Moraes, Roberto A. V., and R. O. Hansen. "Constrained inversion of gravity fields for complex 3-D structures." GEOPHYSICS 66, no. 2 (2001): 501–10. http://dx.doi.org/10.1190/1.1444940.

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As part of a research program to develop gravity interpretation tools that can be merged with seismic techniques, a full 3-D complex structural inversion scheme for (possibly multibody) polyhedral models has been developed. The forward modeling algorithm was adopted from previous work. Because the inverse problem is generally very ill posed, several methods of regularizing the inversion were investigated and a combination of the most useful was adopted. The combination includes (i) a structured matrix formulation for the system equations, (ii) an analytical expression for the Jacobian calculation, (iii) first‐derivative damping, (iv) a choice of damping parameter based on a variation of the trust region method, (v) a weighted scheme for parameter correction, and (vi) complete freezing of degrees of freedom found not to influence the gravity field significantly. This combination yields a robust inversion which was successfully demonstrated on data over the Galveston Island salt dome, offshore Texas. Variations of the technique should be applicable to magnetic data, which would make the method useful for mining problems and petroleum exploration settings involving volcanic structures.

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Ako, Masayuki, Masahiko Machida, Tomio Koyama, Takekazu Ishida, and Masaru Kato. "Vortex state of nano-scaled superconducting complex structures (d-dot)." Physica C: Superconductivity 412-414 (October 2004): 544–47. http://dx.doi.org/10.1016/j.physc.2003.12.058.

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Ako, Masayuki, Masahiko Machida, Tomio Koyama, Takekazu Ishida, and Masaru Kato. "Vortex dynamics in nano-scaled superconducting complex structures (d-dot)." Physica C: Superconductivity 426-431 (October 2005): 122–26. http://dx.doi.org/10.1016/j.physc.2005.03.065.

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Siahkoohi, Hamid R., and Gordon F. West. "3-D seismic imaging of complex structures in glacial deposits." GEOPHYSICS 63, no. 3 (1998): 1041–52. http://dx.doi.org/10.1190/1.1444382.

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A small‐scale, shallow‐penetration 3-D reflection seismic survey has been carried out over stratified glacial formations to test the method’s potential for delineating fine structural details with a reasonable field effort and cost. Recording was carried out with a 96-channel engineering seismograph. Blank shotgun shells were used as the energy source. Field records were obtained with usable reflection energy up to 500 Hz, exploring approximately a 220-m cubical volume. Although special processing was required to attenuate strongly dispersed and scattered surface waves, a stacked data volume of good quality has been assembled. More than 15 reflecting horizons with vertical resolution of about 1.5 m were clearly delineated within the Wisconsin sediments. Results are in good agreement with local outcrops and core information. The identified reflectors (interbeds) within the Late Wisconsin tills are extremely important. These reflectors may provide potential “hydraulic channels” for the movement of surface contaminants through the till into underlying aquifers.

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Brunebarbe, Yohan. "Symmetric differentials and variations of Hodge structures." Journal für die reine und angewandte Mathematik (Crelles Journal) 2018, no. 743 (2018): 133–61. http://dx.doi.org/10.1515/crelle-2015-0109.

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Abstract Let D be a simple normal crossing divisor in a smooth complex projective variety X. We show that the existence on X-D of a non-trivial polarized complex variation of Hodge structures with integral monodromy implies that the pair (X,D) has a non-zero logarithmic symmetric differential (a section of a symmetric power of the logarithmic cotangent bundle). When the corresponding period map is generically immersive, we show more precisely that the logarithmic cotangent bundle is big.

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Thèses sur le sujet "D-Complex Structures"

ROSSI, FEDERICO ALBERTO. "D-Complex Structures on Manifolds: Cohomological properties and deformations." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/41976.

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In questa tesi studiamo alcune proprietà delle "Varietà Doppie" o D-Varietà. In particolare studiamo la teoria delle deformazioni di D-Strutture e di D-Strutture CR, e troviamo una condizione che è equivalente alla classica condizione di Maurer-Cartan che descrive l'integrabilità di deformazioni di D-Strutture. Successivamente prestiamo attenzione alla coomologia delle D-Varietà, provando che una versione D-complessa del del-delbar-Lemma non può essere vera per D-varietà compatte. Inoltre sono stabilite alcune proprietà di sottogruppi speciali della coomologia di de-Rham, ottenute studiando il loro comportamento sotto l'azione di deformazioni. Infine, un risultato riguardante le sottovarietà Lagrangiane minimali dovuto ad Harvey e Lawson riguardante le varietà D-Kahler Ricci-Piatte è generalizzato a una classe di varietà simplettiche quasi D-complesse.<br>We study some properties of Double Manifold, or D-Manifolds. In particular, we study of deformations of D-structures and of CR D-structures, and we found a condition which is equivalent to the classical Maurer-Cartan equation describing the integrability of the deformations. We also focus on the cohomological properties of D-Manifold, showing that a del-delbar-Lemma can not hold for any compact D-Manifold. We also state some properties of special subgroups of de-Rham cohomology, studing also their behaviour under small deformations. Finally, a result by Harvey and Lawson about the minimal Lagrangian Submanifold of a D-Kahler Ricci-flat manifold is generalized to the case of a special almost D-complex symplectic manifold.

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Siahkoohi, Hamid Reza. "3-D seismic imaging of complex structures in near-surface deposits." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27723.pdf.

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Liu, Hengjin 1967. "3-D mesh generation for finite-element modelling of complex natural structures." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99524.

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The finite-element method is based on the discretization of a distributed system. The system subdivision process is called mesh generation. The number, order, geometric characteristics (shape, size and orientation) and physical characteristics (material properties, boundary conditions and load conditions) of elements in the mesh will affect the accuracy of the finite-element solution. The objective of this project is to establish a number of criteria for evaluating 3-D mesh-generation software, and to select the 3-D mesh generator that is most suitable for use in our software pipeline for modelling and simulation of complex natural structures. The evaluation criteria for this project include: ability to preserve the surface mesh during 3-D mesh generation; mesh quality; robustness; time efficiency; and cost. The mesh quality is assessed by visualization methods; histograms of the shape qualities and sizes of elements; solution residuals; condition numbers; and closeness to the exact solution as estimated by a convergence curve. Four unstructured mesh-generation programmes (GiD, Gmsh, GRUMMP and TetGen) have been evaluated. A thin block and three structures (one ligament and two ossicles) of the middle ear were chosen to be the models for the evaluation. A programme was developed to convert the surface definitions describing the models to the native file formats of the mesh-generation programmes, to verify that the surface meshes of these models could be successfully imported into the mesh-generation programmes, and to verify that the resulting volume meshes are topologically correct. The results of the evaluation indicate that the mean value of the shape qualities of elements, the root mean square of the solution residuals, and the closeness to the exact solution are good indicators of the overall mesh quality. The Gmsh programme is finally selected as the best 3-D mesh generator for the purposes of our software pipeline.

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Yuan, Mengtao. "Enhanced and two-dimensional discrete complex image methods for closed-form Green's functions of arbitrary 3-D structures in general multilayered media." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2006. http://proquest.umi.com/login?COPT=REJTPTU0NWQmSU5UPTAmVkVSPTI=&clientId=3739.

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Deschamps, Guillaume. "Espaces twistoriels et structures complexes exotiques." Phd thesis, Université Rennes 1, 2005. http://tel.archives-ouvertes.fr/tel-00011091.

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Dans cette thèse, nous utilisons la théorie des espaces twistoriels afin de construire des structures complexes non standards (en un sens bien précis) sur des produits de 4-variétés réelles avec la sphère de dimension deux. Pour cela nous explicitons l'ensemble des surfaces complexes dont le fibré twistoriel est topologiquement trivial. Dans un deuxième temps nous déterminons parmi ces surfaces celles qui peuvent être munies d'une métrique riemannienne anti-autoduale. De ces résultats, nous déduisons une famille d'exemples simples de 4-variétés réelles parallélisables sans structure complexe. L'espace twistoriel associé à ces variétés admet une structure complexe. C'est notre première classe de 6-variétés munies d'une structure complexe non standard. Une deuxième classe d'exemple sera construite à partir de ces travaux. Enfin, et de façon indépendante, nous étudions brièvement les propriétés de connexités rationnelles des espaces twistoriels.

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da, Silva Ruben Filipe. "Structural studies of surfactant protein D in complex with bacterial lipopolysaccharide ligands." Thesis, Keele University, 2017. http://eprints.keele.ac.uk/4177/.

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This work is focused on the recognition of natural lipopolysaccharide (LPS) by the innate immune protein human lung surfactant protein D (hSP-D) in the form of a biologically active recombinant fragment (rfhSP-D), containing the α-helical coiled-coil and three carbohydrate recognition domains (CRD). Intact LPS from two bacterial strains, S. minnesota (R5 mutant) and H. influenzae type b Eagan (CA7 mutant), were delipidated by means of mild acid hydrolysis, leaving the purified polysaccharide (PS) to be used in X-ray diffraction studies by means of co-crystallisation with rfhSP-D. S. minnesota R7 full LPS was also investigated following development of a suitable solubilisation method which also utilised the LPS from E. coli O111:B4. The structural studies of rfhSP-D bound to H. influenzae Eagan CA7 PS (solved and refined at 2.98 Å) and to S. minnesota rough mutant LPS/PS (solved and refined at 3.3 Å) reveal that rfhSP-D binds to LPS preferentially through the non-terminal inner core heptose HepI via the O6’ and O7’ hydroxyls. rfhSP-D recognition of S. minnesota HepI shows a similar bound heptose orientation to that previously reported for heptose binding by rfhSP-D in the literature with an indication of normal Kdo in the inner core Kdo-Hep-Hep trisaccharide. rfhSP-D recognition of the HepI of H. influenzae Eagan CA7 reveals a novel bound heptose orientation, with the heptose rotated by 180° about C5-C6, resulting in the O6’ and O7’ hydroxyls being interchanged with respect to coordination to Ca1 and protein. The novel orientation of HepI is accompanied by a salt bridge being formed between the flanking residue Arg343 and Glu347, both of which adopt a previously unseen conformation. The novel binding mechanism of rfhSP-D for Eagan CA7 suggests flexibility in recognition and offers evidence to explain why this mutant binds more weakly than the Eagan 4A mutant to both rfhSP-D and hSP-D.

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Welzel, Mario [Verfasser]. "Wave-current-induced scouring processes around complex offshore structures / Mario Welzel." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/1239419627/34.

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Bouhaj, Mohamed [Verfasser]. "Experimental identification of SEA parameters for complex aircraft structures / Mohamed Bouhaj." Düren : Shaker, 2020. http://d-nb.info/1210389711/34.

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Khawaja, Aly Salim. "General semi-structured grid generation for complex 3-D geometries with disparate length scales /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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Belorusova, Anna. "Structure-function studies of the vitamin D nuclear receptor complex with the coactivator MED1." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAJ039.

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Le récepteur de la vitamine D (VDR) est un facteur de transcription activé par la forme active de la vitamine D3. VDR est une cible thérapeutique potentielle pour de multiples pathologies telles que les maladies auto-immunes et neurodégénératives et certains cancers. VDR module l’expression de gènes par le recrutement sélectif de corégulateurs. Les données structurales disponibles à ce jour pour des complexes de récepteur nucléaire-corégulateurs sont très limitées. Cette étude se focalise sur l’architecture du complexe formé par VDR et un grand fragment du coactivateur MED1, une sous-unité du complexe Médiateur qui fait le lien entre les récepteurs nucléaires et la machinerie basale de transcription. Les résultats obtenus nous sont permis de caractériser l'interaction du récepteur avec le coactivateur et de révéler l'architecture globale du complexe. Ce travail fournit une base solide pour la détermination structurale d’autres complexes impliqués dans le contrôle de la transcription<br>The vitamin D nuclear receptor (VDR) is a transcription factor activated by the biologically active form of vitamin D3. VDR is a potential candidate to treat neurodegenerative and autoimmune disorders, and cancer. VDR modulates the expression of vitamin D3-regulated genes by selective recruitment of coregulators of transcription which are, in turn, attractive targets in epigenetic-oriented drug discovery. Available structural data for receptor-coregulator complexes are limited; investigation of such complexes is highly important. The present work focuses on the architecture of the complex between VDR and a large part of the coactivator MED1, a subunit of the Mediator complex linking nuclear receptors to the basal transcription machinery. Obtained results revealed important details of the interaction, as well as the overall organization of the complex. This work provides a solid background for the structural investigation of similar complexes involved in the transcriptional control

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Livres sur le sujet "D-Complex Structures"

Frank Lloyd Wright's Martin House Complex, ed. The Eleanor and Wilson Greatbatch Pavilion: The visitor center at Frank Lloyd Wright's Darwin D. Martin House Complex. Martin House Restoration Corporation, 2008.

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D, Hunt Brian, ed. The Pennsylvania Capitol and General Assembly: [principal photography, Brian D. Hunt]. s.n., 1996.

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Besse, A. L. Einstein Manifolds: Reprint of the 1987 edition, with 22 figures. Springer, 2008.

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Besse, A. L. Einstein Manifolds: Reprint of the 1987 edition, with 22 figures. Springer, 2008.

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Einstein manifolds. Springer-Verlag, 1987.

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Besse, A. L. Einstein Manifolds: Reprint of the 1987 edition, with 22 figures. Springer, 2008.

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Siahkoohi, Hamid Reza. 3-D seismic imaging of complex structures in near-surface deposits. 1997.

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Introduction to Stokes Structures Lecture Notes in Mathematics. Springer, 2012.

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Frank Lloyd Wright's Martin House Complex. Martin House Restoration Corp., 2004.

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M¨uhlherr, Bernhard, Holger P. Petersson, and Richard M. Weiss. Existence. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691166902.003.0016.

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This chapter proves that Bruhat-Tits buildings exist. It begins with a few definitions and simple observations about quadratic forms, including a 1-fold Pfister form, followed by a discussion of the existence part of the Structure Theorem for complete discretely valued fields due to H. Hasse and F. K. Schmidt. It then considers the generic unramified cases; the generic semi-ramified cases, the generic ramified cases, the wild unramified cases, the wild semi-ramified cases, and the wild ramified cases. These cases range from a unique unramified quadratic space to an unramified separable quadratic extension, a tamely ramified division algebra, a ramified separable quadratic extension, and a unique unramified quaternion division algebra. The chapter also describes ramified quaternion division algebras D₁, D₂, and D₃ over K containing a common subfield E such that E/K is a ramified separable extension.

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Chapitres de livres sur le sujet "D-Complex Structures"

Ben-Artzi, M., and J. Falcovitz. "The GRP Treatment of 2-D Complex Wave Structures." In Hyperbolic Problems: Theory, Numerics, Applications. Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-55711-8_10.

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Okada, H., G. Yagawa, H. Kawai, et al. "The State-of-the-Art Methodology to Compute the 3-D Stress Intensity Factors for Arbitrary Shaped Cracks in Complex Shaped Structures." In Computational Methods in Engineering & Science. Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/978-3-540-48260-4_46.

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James, Tamara, Meng-Lun Hsieh, Leslie Knipling, and Deborah Hinton. "Determining the Architecture of a Protein–DNA Complex by Combining FeBABE Cleavage Analyses, 3-D Printed Structures, and the ICM Molsoft Program." In Methods in Molecular Biology. Springer New York, 2015. http://dx.doi.org/10.1007/978-1-4939-2877-4_3.

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Bode, Wolfram. "X-Ray Crystal Structures of Thrombin in Complex with D-Phe-Pro-Arg and with Small Benzamidine- and Arginine-Based “Non-Peptidic” Inhibitors." In Advances in Experimental Medicine and Biology. Springer US, 1993. http://dx.doi.org/10.1007/978-1-4899-2418-6_2.

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Sussman, J. L., M. Harel, M. Raves, D. Quinn, and I. Silman. "3-D Structure of Acetylcholinesterase and Its Complexes with Anticholinesterase Agents." In Modelling of Biomolecular Structures and Mechanisms. Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0497-5_34.

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Winter, C., B. Krusche, K. P. Lieb, et al. "Complete Spectroscopy of 87,88,89Sr with (n,γ) and (d,p) Reactions?*." In Nuclear Structure of the Zirconium Region. Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73958-3_23.

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Sussman, J. L., M. Harel, and I. Silman. "3-D Structure of Acetylcholinesterase and Complexes of it with Anticholinesterase Agents." In The Jerusalem Symposia on Quantum Chemistry and Biochemistry. Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2718-9_14.

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Buslov, D. K., N. A. Nikonenko, and R. G. Zhbankov. "Analysis of the Complex Structure of Absorption Bands in the IR Spectrum of α-D-Glucose by Regularized Method of Deconvolution." In Spectroscopy of Biological Molecules: Modern Trends. Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5622-6_117.

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Palmer, Richard A., Pingyun Chen, Susan E. Plunkett, and James L. Chao. "Excited State Structure and Relaxation Dynamics of Polypyridyl Complexes of Low Spin d 6 Metal Ions by Means of Step-Scan FTIR Time-Resolved Spectroscopy (S2FT-IR TRS)." In Progress in Fourier Transform Spectroscopy. Springer Vienna, 1997. http://dx.doi.org/10.1007/978-3-7091-6840-0_149.

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Kayser, Christian, Jan Akkermann, Maria E. Moreyra Garlock, et al. "Part D Complex Structures." In Manual of Structural Design. DETAIL, 2022. http://dx.doi.org/10.11129/9783955535667-005.

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Actes de conférences sur le sujet "D-Complex Structures"

Chira-Oliva, Pedro A., P. Nascimento Elias, and João C. R. Cruz. "3-D modeling of complex geological structures." In 11th International Congress of the Brazilian Geophysical Society & EXPOGEF 2009, Salvador, Bahia, Brazil, 24-28 August 2009. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2009. http://dx.doi.org/10.1190/sbgf2009-303.

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A. Chira-Oliva, Pedro, Elias P. Nascimento, and João C.R. Cruz. "3-D Modeling Of Complex Geological Structures." In 11th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2009. http://dx.doi.org/10.3997/2214-4609-pdb.195.1624_evt_6year_2009.

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Yang, B. "Strip distributed transfer function method for analysis of complex 2-D structures." In 37th Structure, Structural Dynamics and Materials Conference. American Institute of Aeronautics and Astronautics, 1996. http://dx.doi.org/10.2514/6.1996-1398.

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Llewellyn-Jones, Thomas M., Bruce W. Drinkwater, and Richard S. Trask. "3-D printed composites with ultrasonically arranged complex microstructure." In SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring, edited by Raúl J. Martín-Palma, Akhlesh Lakhtakia, and Mato Knez. SPIE, 2016. http://dx.doi.org/10.1117/12.2218855.

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Lancellotti, V., B. P. de Hon, and A. G. Tijhuis. "A domain decomposition method for solving 3-D complex structures." In Propagation in Wireless Communications (ICEAA). IEEE, 2011. http://dx.doi.org/10.1109/iceaa.2011.6046347.

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Siahkoohi, H. R., and G. F. West. "3‐D seismic imaging of complex structures in glacial deposits." In SEG Technical Program Expanded Abstracts 1996. Society of Exploration Geophysicists, 1996. http://dx.doi.org/10.1190/1.1826795.

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Wang, Tan Kin, and Kenneth R. McClay. "Gaussian beam seismic modeling and processing of complex 3‐D structures." In SEG Technical Program Expanded Abstracts 1995. Society of Exploration Geophysicists, 1995. http://dx.doi.org/10.1190/1.1887325.

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Kapotas, Sotiris, Jean‐Luc Guiziou, and Michel Barut. "SISTRE: 3‐D velocity determination of complex geologic structures via reflection tomography." In SEG Technical Program Expanded Abstracts 1993. Society of Exploration Geophysicists, 1993. http://dx.doi.org/10.1190/1.1822572.

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Diet, Jean Paul, and Ian F. Jones. "Strategic seismic imaging: A stepwise approach to 3‐D prestack imaging of complex structures." In SEG Technical Program Expanded Abstracts 1994. Society of Exploration Geophysicists, 1994. http://dx.doi.org/10.1190/1.1822748.

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Lee, S. Y., R. A. Meek, R. K. Ho, et al. "Imaging complex salt structures in the Gulf of Mexico with 3‐D depth migration." In SEG Technical Program Expanded Abstracts 1993. Society of Exploration Geophysicists, 1993. http://dx.doi.org/10.1190/1.1822399.

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Rapports d'organisations sur le sujet "D-Complex Structures"

Ebeling, Robert, та Barry White. Load and resistance factors for earth retaining, reinforced concrete hydraulic structures based on a reliability index (β) derived from the Probability of Unsatisfactory Performance (PUP) : phase 2 study. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/39881.

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This technical report documents the second of a two-phase research and development (R&D) study in support of the development of a combined Load and Resistance Factor Design (LRFD) methodology that accommodates geotechnical as well as structural design limit states for design of the U.S. Army Corps of Engineers (USACE) reinforced concrete, hydraulic navigation structures. To this end, this R&D effort extends reliability procedures that have been developed for other non-USACE structural systems to encompass USACE hydraulic structures. Many of these reinforced concrete, hydraulic structures are founded on and/or retain earth or are buttressed by an earthen feature. Consequently, the design of many of these hydraulic structures involves significant soil structure interaction. Development of the required reliability and corresponding LRFD procedures has been lagging in the geotechnical topic area as compared to those for structural limit state considerations and have therefore been the focus of this second-phase R&D effort. Design of an example T-Wall hydraulic structure involves consideration of five geotechnical and structural limit states. New numerical procedures have been developed for precise multiple limit state reliability calculations and for complete LRFD analysis of this example T-Wall reinforced concrete, hydraulic structure.

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Montville, Thomas J., and Roni Shapira. Molecular Engineering of Pediocin A to Establish Structure/Function Relationships for Mechanistic Control of Foodborne Pathogens. United States Department of Agriculture, 1993. http://dx.doi.org/10.32747/1993.7568088.bard.

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This project relates the structure of the bacteriocin molecule (which is genetically determined) to its antimicrobial function. We have sequenced the 19,542 bp pediocin plasmid pMD136 and developed a genetic transfer system for pediococci. The pediocin A operon is complex, containing putative structural, immunity, processing, and transport genes. The deduced sequence of the pediocin A molecule contains 44 amino acids and has a predicted PI of 9.45. Mechanistic studies compared the interaction of pediocin PA-1 and nisin with Listeria monocytgenes cells and model lipid systems. While significant nisin-induced intracellular ATP depletion is caused by efflux, pediocin-induced depletion is caused exclusively by hydrolysis. Liposomes derived from L. monocytogenes phospholipids were used to study the physical chemistry of pediocin and nisin interactions with lipids. Their different pH optima are the results of different specific ionizable amino acids. We generated a predicted 3-D structural model for pediocin PA-1 and used a variety of mutant pediocins to demonstrate that the "positive patch" at residues 11 and 12 (and not the YGNGV consensus sequence) is responsible for the binding step of pediocin action. This structure/function understanding gained here provides necessary prerequisites to the more efficacious use of bacteriocins to control foodborne pathogens.

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Ansari, S. M., E. M. Schetselaar, and J. A. Craven. Three-dimensional magnetotelluric modelling of the Lalor volcanogenic massive-sulfide deposit, Manitoba. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328003.

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Unconstrained magnetotelluric inversion commonly produces insufficient inherent resolution to image ore-system fluid pathways that were structurally thinned during post-emplacement tectonic activity. To improve the resolution in these complex environments, we synthesized the 3-D magnetotelluric (MT) response for geologically realistic models using a finite-element-based forward-modelling tool with unstructured meshes and applied it to the Lalor volcanogenic massive-sulfide deposit in the Snow Lake mining camp, Manitoba. This new tool is based on mapping interpolated or simulated resistivity values from wireline logs onto unstructured tetrahedral meshes to reflect, with the help of 3-D models obtained from lithostratigraphic and lithofacies drillhole logs, the complexity of the host-rock geological structure. The resulting stochastic model provides a more realistic representation of the heterogeneous spatial distribution of the electric resistivity values around the massive, stringer, and disseminated sulfide ore zones. Both models were combined into one seamless tetrahedral mesh of the resistivity field. To capture the complex resistivity distribution in the geophysical forward model, a finite-element code was developed. Comparative analyses of the forward models with MT data acquired at the Earth's surface show a reasonable agreement that explains the regional variations associated with the host rock geological structure and detects the local anomalies associated with the MT response of the ore zones.

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Applebaum, Shalom W., Lawrence I. Gilbert, and Daniel Segal. Biochemical and Molecular Analysis of Juvenile Hormone Synthesis and its Regulation in the Mediterranean Fruit Fly (Ceratitis capitata). United States Department of Agriculture, 1995. http://dx.doi.org/10.32747/1995.7570564.bard.

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Original Objectives and revisions: (1) "To determine the biosynthetic pathway of JHB3 in the adult C. capitata CA in order to establish parameters for the future choice and synthesis of suitable inhibitors". Modified: to determine the pattern of FR-7 biosynthesis during normal reproductive maturation, and identify enzymes potentially involved in its synthesis. (2) "To correlate allatal epoxidase activity to the biosynthesis of JHB3 at different stages of reproductive maturation/vitellogenesis and evaluate the hypothesis that a specific JH-epoxidase may be rate limiting". Modified: to study the effects of epoxidase inhibitors on the pattern of allatal JH biosynthesis in vitro and on female reproduction in vive. (3) "To probe and clone the gene homologous to ap from C. capitata, determine its exon-intron organization, sequence it and demonstrate its spatial and temporal expression in larvae, pupae and adults." The "Medfly" (Ceratitis capitata) is a serious polyphagous fruit pest, widely distributed in subtropical regions. Damage is caused by oviposition and subsequent development of larvae. JH's are dominant gonadotropic factors in insects. In the higher Diptera, to which the Medfly belongs, JHB3 is a major homolog. It comprises 95% of the total JH produced in vitro in D. melanogaster, with JH-III found as a minor component. The biosynthesis of both JH-III and JHB3 is dependent on epoxidation of double bonds in the JH molecule. The specificity of such epoxidases is unknown. The male accessory gland D. melanogaster produces a Sex Peptide, transferred to the female during copulation. SP reduces female receptivity while activating specific JH biosynthesis in vitro and inducing oviposition in vive. It also reduces pheromone production and activates CA of the moth Helicoverpa armigera. In a previous study, mutants of the apterous (ap) gene of D. melanogaster were analyzed. This gene induces previteilogenic arrest which can be rescued by external application of JH. Considerable progress has been made in recombinant DNA technology of the Medfly. When fully operative, it might be possible to effectively transfer D. melanogaster endocrine gene-lesions into the Medfly as a strategy for their genetic control. A marked heterogeneity in the pattern of JH homologs produced by Medfly CA was observed. Contrary to the anticipated biosynthesis of JHB;, significant amounts of an unknown JH-like compound, of unknown structure and provisionally termed FR-7, were produced, in addition to significant amounts of JH-III and JHB3. Inhibitors of monooxygenases, devised for their effects on ecdysteroid biosynthesis, affect Medfly JH biosynthesis but do not reduce egg deposition. FR-7 was isolated from incubation media of Medfly CA and examined by various MS procedures, but its structure is not yet resolved. MS analysis is being done in collaboration with Professor R.R.W. Rickards of the Australian National University in Canberra, Australia. A homologue of the ap gene of D. melanogaster exists in the Medfly. LIM domains and the homeo-domain, important for the function of the D. melanogaster ap gene, are conserved here too. Attempts to clone the complete gene were unsuccessful. Due to the complexity of JH homologs, presence of related FR-7 in the biosynthetic products of Medfly CA and lack of reduction in eggs deposited in the presence of monooxygenase inhibitors, inhibition of epoxidases is not a feasible alternative to control Medfly reproduction, and raises questions which cannot be resolved within the current dogma of hormonal control of reproduction in Diptera. The Medfly ap gene has similar domains to the D. melanogaster ap gene. Although mutant ap genes are involved in JH deficiency, ap is a questionable candidate for an endocrine lesion, especially since the D. melanogoster gene functions is a transcription factor.

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Shomer, Ilan, Ruth E. Stark, Victor Gaba, and James D. Batteas. Understanding the hardening syndrome of potato (Solanum tuberosum L.) tuber tissue to eliminate textural defects in fresh and fresh-peeled/cut products. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7587238.bard.

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The project sought to understand factors and mechanisms involved in the hardening of potato tubers. This syndrome inhibits heat softening due to intercellular adhesion (ICA) strengthening, compromising the marketing of industrially processed potatoes, particularly fresh peeled-cut or frozen tubers. However, ICA strengthening occurs under conditions which are inconsistent with the current ideas that relate it to Ca-pectate following pectin methyl esterase (PME) activity or to formation of rhamnogalacturonan (RG)-II-borate. First, it was necessary to induce strengthening of the middle lamellar complex (MLX) and the ICA as a stress response in some plant parenchyma. As normally this syndrome does not occur uniformly enough to study it, we devised an efficient model in which ICA-strengthening is induced consistently under simulated stress by short-chain, linear, mono-carboxylic acid molecules (OAM), at 65 oC [appendix 1 (Shomer&Kaaber, 2006)]. This rapid strengthening was insufficient for allowing the involved agents assembly to be identifiable; but it enabled us to develop an efficient in vitro system on potato tuber parenchyma slices at 25 ºC for 7 days, whereas unified stress was reliably simulated by OAMs in all the tissue cells. Such consistent ICA-strengthening in vitro was found to be induced according to the unique physicochemical features of each OAM as related to its lipophilicity (Ko/w), pKa, protonated proportion, and carbon chain length by the following parameters: OAM dissociation constant (Kdiss), adsorption affinity constant (KA), number of adsorbed OAMs required for ICA response (cooperativity factor) and the water-induced ICA (ICAwater). Notably, ICA-strengthening is accompanied by cell sap leakage, reflecting cell membrane rupture. In vitro, stress simulation by OAMs at pH<pKa facilitated the consistent assembly of ICAstrengthening agents, which we were able to characterize for the first time at the molecular level within purified insoluble cell wall of ICA-strengthened tissue. (a) With solid-state NMR, we established the chemical structure and covalent binding to cell walls of suberin-like agents associated exclusively with ICA strengthening [appendix 3 (Yu et al., 2006)]; (b) Using proteomics, 8 isoforms of cell wall-bound patatin (a soluble vacuolar 42-kDa protein) were identified exclusively in ICA-strengthened tissue; (c) With light/electron microscopy, ultrastructural characterization, histochemistry and immunolabeling, we co-localized patatin and pectin in the primary cell wall and prominently in the MLX; (d) determination of cell wall composition (pectin, neutral sugars, Ca-pectate) yielded similar results in both controls and ICA-strengthened tissue, implicating factors other than PME activity, Ca2+ or borate ions; (e) X-ray powder diffraction experiments revealed that the cellulose crystallinity in the cell wall is masked by pectin and neutral sugars (mainly galactan), whereas heat or enzymatic pectin degradation exposed the crystalline cellulose structure. Thus, we found that exclusively in ICA-strengthened tissue, heat-resistant pectin is evident in the presence of patatin and suberinlike agents, where the cellulose crystallinity was more hidden than in fresh control tissue. Conclusions: Stress response ICA-strengthening is simulated consistently by OAMs at pH< pKa, although PME and formation of Ca-pectate and RG-II-borate are inhibited. By contrast, at pH>pKa and particularly at pH 7, ICA-strengthening is mostly inhibited, although PME activity and formation of Ca-pectate or RG-II-borate are known to be facilitated. We found that upon stress, vacuolar patatin is released with cell sap leakage, allowing the patatin to associate with the pectin in both the primary cell wall and the MLX. The stress response also includes formation of covalently bound suberin-like polyesters within the insoluble cell wall. The experiments validated the hypotheses, thus led to a novel picture of the structural and molecular alterations responsible for the textural behavior of potato tuber. These findings represent a breakthrough towards understanding of the hardening syndrome, laying the groundwork for potato-handling strategies that assure textural quality of industrially processed particularly in fresh peeled cut tubers, ready-to-prepare and frozen preserved products.

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Ripoll, Santiago, Tabitha Hrynick, Ashley Ouvrier, Megan Schmidt-Sane, Federico Marco Federici, and Elizabeth Storer. 10 façons dont les gouvernements locaux en milieu urbain multiculturel peuvent appuyer l’égalité vaccinale en cas de pandémie. SSHAP, 2023. http://dx.doi.org/10.19088/sshap.2023.001.

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Si l’on s’en tient aux chiffres de la vaccination contre la COVID-19 dans les pays du G7, la campagne apparaît comme un véritable succès tant au niveau global qu’au niveau national. En effet, à ce jour, 79,4 % de la population totale des pays du G7 a reçu une première dose, 72,9 % une seconde, et 45,4 % une dose de rappel (données du 28 avril 2022) 1 En France, c’est 80,6 % de la population totale qui a reçu une première dose, 78,2 % qui a reçu deux doses, et 55,4 % qui a reçu un rappel (données du 28 avril 2022).2 Au Royaume-Uni, 79,3 % de la population totale a reçu une première dose, 74,1 % une seconde, et 58,5 % un rappel.1 Enfin, en Italie, 85,2 % de la population totale a reçu une première dose, 80,4 % a reçu deux doses et 66,5 % a reçu leurs rappels (données du 28 avril 2022). Ces taux de vaccination élevés masquent pourtant des disparités importantes à l’intérieur de chaque pays. Ainsi, à Marseille, deuxième ville de France, moins de 50 % des habitants des quartiers nord de la ville étaient vaccinés à la fin de l’année 2021, alors que plus de 70 % des habitants des quartiers sud l’étaient au même moment.3 Dans le quartier populaire de Ealing, situé au nord-ouest de Londres, 70 % de la population admissible avait reçu une première dose, soit près de 10 % de moins que la moyenne nationale. 4 (Données du 4 avril 2022). Des disparités similaires ont été observées dans d’autres métropoles urbaines des pays du G7. Ce document examine ces disparités au prisme de la notion d’« (in)égalité vaccinale ». En s’appuyant sur des recherches qualitatives menées pendant la campagne de vaccination de la COVID-19 dans les quartiers nord de Marseille, le quartier de Ealing à Londres (Nord-ouest) et dans la région de l'Émilie-Romagne et à Rome, en Italie, il montre comment les autorités locales peuvent agir pour atténuer ces inégalités. Mieux comprendre les inégalités en matière de vaccins fut primordial lors de la pandémie de la COVID-19 en ce sens que les populations sous-vaccinées étaient la plupart du temps des minorités ethniques ou culturelles, vivant dans des zones défavorisées, ou sans-papiers, donc plus susceptibles de contracter la COVID-19, et d’en subir les conséquences les plus dramatiques. 5 6 7 8 Ainsi, à Ealing, quatre mois après la campagne de vaccination, seulement 57,6% des personnes dans le décile de pauvreté le plus bas avaient reçu une dose, contre 81% des personnes dans le décile le plus aisé. 9 En outre, 89,2 % des résidents britanniques blancs de Ealing étaient vaccinés, contre 64 % des Pakistanais et 49,3 % des habitants issus des Caraïbes.9 À Rome, comme c’est le cas dans d’autres métropoles urbaines des pays du G7, nos données révèlent des disparités particulières importantes entre le recours aux vaccins des populations sans papiers et celui des citoyens établis. Les facteurs d’inégalité vaccinale dans ces environnements urbains sont complexes et liés à l’interaction de nombreux phénomènes tels que les inégalités économiques, le racisme structurel, l'inégalité d'accès aux soins de santé, la méfiance envers les professionnels de santé, les représentants de l'État, et plus encore. Les collectivités locales tout comme les professionnels de la santé, les groupes communautaires et les résidents jouent un rôle clé dans la manière dont s’exprime l’(in)égalité vaccinale. Pour autant, peu de leçons ont été systématiquement tirées des efforts menés en matière d’ «engagement vaccinal » au niveau local. Dans ce document, nous proposons d’expliquer comment l’expérience des inégalités structurelles se recoupe avec celle des habitants, et comment ces expériences ont été prises en compte ou au contraire ignorées dans la promotion et l’administration des vaccins contre la COVID-19 par les collectivités locales. Nous adressons également un ensemble de recommandations qui s’appliquent aux programmes de « vaccination de rattrapage » contre la COVID-19 (visant à atteindre les personnes qui n’ont pas encore reçu leur schéma vaccinal complet), mais elles concernent également les programmes de vaccination d'urgence à venir. Ce document repose sur des recherches menées entre octobre et décembre 2021 à Marseille et sur des échanges réguliers avec les autorités du Borough de Ealing initiés dès mai 2021. Il identifie comment les gouvernements locaux, les acteurs de la santé, les groupes communautaires et les résidents jouent un rôle clé dans la production d’(in)égalités vaccinales. Ce document a été élaboré pour la SSHAP par Santiago Ripoll (IDS), Tavitha Hrynick (IDS), Ashley Ouvrier (LaSSA), Megan Schmidt-Sane (IDS), Federico Federici (UCL) et Elizabeth Storer (LSE). Il a été revu par Eloisa Franchi (Université de Pavie) et Ellen Schwartz (Conseil de santé publique de Hackney). La recherche a été financée par la British Academy COVID-19 Recovery : Fonds G7 (COVG7210038). Les recherches ont été menées à l’Institut d’études du développement (IDS), à l’Université de Sussex et au Laboratoire des sciences sociales appliquées (LaSSA). La SSHAP en assume la responsabilité.

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Shenker, Moshe, Paul R. Bloom, Abraham Shaviv, et al. Fate of Phosphorus Originated from Treated Wastewater and Biosolids in Soils: Speciation, Transport, and Accumulation. United States Department of Agriculture, 2011. http://dx.doi.org/10.32747/2011.7697103.bard.

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Beneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levelsBeneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levels that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction.

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