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See detailDual effects of an extra disulfide bond on the activity and stability of a cold-adapted alpha-amylase
D'Amico, Salvino ULg; Gerday, Charles ULg; Feller, Georges ULg

in Journal of Biological Chemistry (2002), 277(48), 46110-46115

Chloride-dependent alpha-amylases constitute a well conserved family of enzymes thereby allowing investigation of the characteristics of each member to understand, for example, relevant properties ... [more ▼]

Chloride-dependent alpha-amylases constitute a well conserved family of enzymes thereby allowing investigation of the characteristics of each member to understand, for example, relevant properties required for environmental adaptation. In this context, we have constructed a double mutant (Q58C/A99C) of the cold-active and heat-labile alpha-amylase from the Antarctic bacterium Pseudoalteromonas haloplanktis, defined on the basis of its strong similarity with the mesophilic enzyme from pig pancreas. This mutant was characterized to understand the role of an extra disulfide bond specific to warm-blooded animals and located near the entrance of the catalytic cleft. We show that the catalytic parameters of the mutant are drastically modified and similar to those of the mesophilic enzyme. Calorimetric studies demonstrated that the mutant is globally stabilized (DeltaDeltaG = 1.87 kcal/mol at 20 degrees C) when compared with the wild-type enzyme, although the melting point (T-m) was not increased. Moreover, fluorescence quenching experiments indicate a more compact structure for the mutated a-amylase. However, the strain imposed on the active site architecture induces a 2-fold higher thermal inactivation rate at 45 degreesC as well as the appearance of a less stable calorimetric domain. It is concluded that stabilization by the extra disulfide bond arises from an enthalpy-entropy compensation effect favoring the enthalpic contribution. [less ▲]

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See detailDual energy X-ray absorptiometry-based assessment of male patients using standardized bone density values and a national reference database
Goemaere, S.; Vanderschueren, D.; Kaufman, J. M. et al

in Journal of Clinical Densitometry (2007), 10(1, JAN-MAR), 25-33

Dual energy X-ray absorptiometry (DXA) measurements from different manufacturers provide different bone mineral density (BMD) values and derived T-scores and Z-scores. These differences result partly from ... [more ▼]

Dual energy X-ray absorptiometry (DXA) measurements from different manufacturers provide different bone mineral density (BMD) values and derived T-scores and Z-scores. These differences result partly from technical differences in the algorithms for the determination of bone mineral content and bone area and partly from the use of different manufacturer-derived reference databases. The present study was to implement a uniforrn expression of BNID in all male patients by using standardized BMD (sBMD) values and referring to a newly established national male reference sample. In 8 bone densitometry centers throughout Belgium 229 young healthy men were measured on Hologic (Bedford, MA) or GE-Lunar (Madison, WI) bone densitometers. Quality control procedures were implemented and site cross-calibration performed using the European Spine Phantom. Absolute BMD values were converted to standardized values by validated formulas (sBMD). Clinically acceptable between-center differences were noted. No discrepancy was observed in terms of mean sBMD and standard deviations at the lumbar spine and proximal femur between the Belgian and the US reference populations. Region-specific sBMD thresholds for the diagnosis of male osteoporosis were calculated. The current data provide a basis to implement a nation-wide, uniform expression of BMD in male patients and allow harmonization of the BMD-based diagnosis and treatment of osteoporosis in men. [less ▲]

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See detailDual finite element formulations for the three-dimensional modeling of both inductive and capacitive effects in massive inductors
Dular, Patrick ULg; Kuo-Peng, Patrick

in IEEE Transactions on Magnetics (2006), 42(4), 743-746

Dual finite element formulations are developed for modeling both inductive and capacitive effects in massive inductors. Mixed finite elements are used to satisfy each chosen conformity level for the ... [more ▼]

Dual finite element formulations are developed for modeling both inductive and capacitive effects in massive inductors. Mixed finite elements are used to satisfy each chosen conformity level for the unknown fields and to naturally define the global quantities involved in the inductive and capacitive circuit relations, to be used in circuit coupling. The interest of satisfying conformity properties for the considered magnetic and electric coupled problems is shown and the related mathematical and discrete tools for any wished conformity level are developed. [less ▲]

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See detailDual finite element formulations taking eddy currents in lamination stacks into account
Dular, Patrick ULg; Gyselinck, J.; Geuzaine, Christophe ULg et al

in Proceedings of the 5th Brazilian Conference on Electromagnetics, CBMag 2002 (2002)

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See detailDual Formulations for Accurate Thin Shell Models in a Finite Element Subproblem Method
Dang, Quoc Vuong ULg; Dular, Patrick ULg; Vazquez Sabariego, Ruth ULg et al

in Proceeding of the 19th COMPUMAG Conference on the Computation of Electromagnetic Fields, 2013 (2013, April 01)

A subproblem finite with dual finite element magnetostatic and magnetodynamic formulations is developed for correcting the inaccuracies near edges and corners coming from thin shell models, that replace ... [more ▼]

A subproblem finite with dual finite element magnetostatic and magnetodynamic formulations is developed for correcting the inaccuracies near edges and corners coming from thin shell models, that replace thin volume regions by surfaces. The surface-to-volume correction problem is defined as one of the multiple subproblems applied to a complete problem, considering successive additions of inductors and magnetic or conducting regions, some of these being thin regions. Each SP requires a proper adapted mesh of its regions, which facilitates meshing and increases computational e ciency. [less ▲]

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See detailDual Formulations for Low Frequency Thin Conducting Magnetic Shell Modeling
Geuzaine, Christophe ULg; Dular, Patrick ULg; Klinkenberg, P. et al

in Proceedings of the 8th International IGTE Symposium on Numerical Field Calculation in Electrical Engineering (1998)

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See detailDual Formulations for the Modeling of Thin Conducting Magnetic Shells
Geuzaine, Christophe ULg; Dular, Patrick ULg; Legros, Willy ULg

in Procedings of the Eighth International Symposium on Numerical Field Calculation in Electrical Engineering (IGTE 1998) (1998)

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See detailDual Formulations for the Modeling of Thin Electromagnetic Shells using Edge Elements
Geuzaine, Christophe ULg; Dular, Patrick ULg; Legros, Willy ULg

in IEEE Transactions on Magnetics (2000), 36(4), 799-803

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See detailDual Formulations for the Modeling of Thin Electromagnetic Shells using Edge Elements
Geuzaine, Christophe ULg; Dular, Patrick ULg; Legros, Willy ULg

in Proceedings of the 12th COMPUMAG Conference on the Computation of Electromagnetic Fields (1999)

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See detailDual function of ERR alpha in breast cancer and bone metastasis formation: implication of VEGF and osteoprotegerin.
Fradet, Anais; Sorel, Helene; Bouazza, Lamia et al

in Cancer Research (2011), 71(17), 5728-38

Bone metastasis is a complication occurring in up to 70% of advanced breast cancer patients. The estrogen receptor-related receptor alpha (ERRalpha) has been implicated in breast cancer and bone ... [more ▼]

Bone metastasis is a complication occurring in up to 70% of advanced breast cancer patients. The estrogen receptor-related receptor alpha (ERRalpha) has been implicated in breast cancer and bone development, prompting us to examine whether ERRalpha may function in promoting the osteolytic growth of breast cancer cells in bone. In a mouse xenograft model of metastatic human breast cancer, overexpression of wild-type ERRalpha reduced metastasis, whereas overexpression of a dominant negative mutant promoted metastasis. Osteoclasts were directly affected and ERRalpha upregulated the osteoclastogenesis inhibitor, osteoprotegerin (OPG), providing a direct mechanistic basis for understanding how ERRalpha reduced breast cancer cell growth in bone. In contrast, ERRalpha overexpression increased breast cancer cell growth in the mammary gland. ERRalpha-overexpressing primary tumors were highly vascularized, consistent with an observed upregulation of angiogenic growth factor, the VEGF. In support of these findings, we documented that elevated expression of ERRalpha mRNA in breast carcinomas was associated with high expression of OPG and VEGF and with disease progression. In conclusion, our results show that ERRalpha plays a dual role in breast cancer progression in promoting the local growth of tumor cells, but decreasing metastatic growth of osteolytic lesions in bone. [less ▲]

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See detailDual Harmonic and Time Approaches for the Design of Microwave Devices
Meys, B.; Geuzaine, Christophe ULg; Henrotte, F. et al

in IEEE Transactions on Magnetics (1999), 35(3), 1829--1832

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See detailDual Harmonic and Time Approaches for the Design of Microwave Devices
Meys, B.; Geuzaine, Christophe ULg; Henrotte, F. et al

in Proceedings of the Eighth Biennal IEEE Conference on Electromagnetic Field Computation (1998)

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See detailDual living free radical and ring opening polymerizations from a double-headed initiator
Hawker, Craig J; Hedrick, James L; Malmström, Eva E et al

in Macromolecules (1998), 31(2), 213-219

The concept of performing dual living polymerizations from a single initiating molecule with no intermediate activation, or transformation, steps is presented. The compatibility of “living”, or controlled ... [more ▼]

The concept of performing dual living polymerizations from a single initiating molecule with no intermediate activation, or transformation, steps is presented. The compatibility of “living”, or controlled free radical procedures, either nitroxide mediated or atom transfer radical polymerization (ATRP), with the living ring opening polymerization of ε-caprolactone, and vice versa, is demonstrated by the synthesis of a variety of well-defined block copolymers. For example, from a hydroxy-functionalized alkoxyamine, either the living ring opening polymerization of ε-caprolactone, or the “living” free radical polymerization of styrene can be performed leading to narrow polydispersity polymeric initiators. These polymeric initiators can then be used to initiate the living polymerization of the other monomer system without the need for intermediate steps. In a similar way, hydroxy-functionalized ATRP initiators can be used as bifunctional initiators for the polymerization of both ε-caprolactone and a variety of other vinyl monomers. The novel block copolymers that are obtained were shown to have low polydispersities and controllable molecular weights for both of the blocks. [less ▲]

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See detailDual Magnetodynamic Formulations and Their Source Fields Associated with Massive and Stranded Inductors
Dular, Patrick ULg; Kuo-Peng, P.; Geuzaine, Christophe ULg et al

in IEEE Transactions on Magnetics (2000), 36(4), 1293--1299

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See detailDual Magnetodynamic Formulations and Their Source Fields Associated with Massive and Stranded Inductors
Dular, Patrick; Kuo-Peng, P.; Geuzaine, Christophe ULg et al

in Proceedings of the 12th COMPUMAG Conference on the Computation of Electromagnetic Fields (1999)

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See detailDual Magnetodynamic Formulations and their Source Fields associated with Stranded Inductors
Dular, Patrick ULg; Kuo-Peng, P.; Geuzaine, Christophe ULg et al

in Proceedings of the 12th Conference on the Computation of Electromagnetic Fields, COMPUMAG 1999 (1999)

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See detailDual methods for optimizing finite element flexural systems
Fleury, Claude ULg; Sander, G.

in Computer Methods in Applied Mechanics & Engineering (1983), 37(3), 249-275

Modern numerical methods for the optimization of large discretized systems are now well developed and highly efficient in the case of thin walled elastic structures modeled by finite elements. However ... [more ▼]

Modern numerical methods for the optimization of large discretized systems are now well developed and highly efficient in the case of thin walled elastic structures modeled by finite elements. However, this is not yet true for structures whose components are subject simultaneously to bending and extension loads. In this paper, the idea of Generalized Optimality Criterion (GOC), set forth in previous papers for bar, membrane, and pure bending elements, is extended to deal with general beam and flat shell elements. The modifications brought to the GOC result in explicit approximations for the behavior constraints that are correct up to the first order, but that exhibit a more complex algebraic form. Indeed these explicit expressions are no longer merely linear in the reciprocal design variables. However, they continue to be additively separable, and therefore dual methods remain fully applicable, just as in the original statement of the GOC approach. Numerical examples will be offered to demonstrate the efficiency of the method presented. [less ▲]

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