Search results for "folds"

Boundary Behavior of Harmonic Functions on Gromov Hyperbolic Manifolds

2013

Non-equivalent hyperbolic knots

2002

We construct, for each integer n 3, pairs of non-equivalent hyperbolic knots with the same 2fold and n-fold cyclic branched covers. We also discuss necessary conditions for such pairs of knots to exist.  2001 Elsevier Science B.V. All rights reserved. MSC: primary 57M25; secondary 57M12, 57M50

Designed biodegradable hydrogel structures prepared by stereolithography using poly(ethylene glycol)/poly(D,L-lactide)-based resins

2010

Designed three-dimensional biodegradable poly(ethylene glycol)/poly(D,L-lactide) hydrogel structures were prepared for the first time by stereolithography at high resolutions. A photo-polymerisable aqueous resin comprising PDLLA-PEG-PDLLA-based macromer, visible light photo-initiator, dye and inhibitor in DMSO/water was used to build the structures. Porous and non-porous hydrogels with well-defined architectures and good mechanical properties were prepared. Porous hydrogel structures with a gyroid pore network architecture showed narrow pore size distributions, excellent pore interconnectivity and good mechanical properties. The structures showed good cell seeding characteristics, and human…

Physico-chemical and mechanical characterization of in-situ forming xyloglucan gels incorporating a growth factor to promote cartilage reconstruction

2016

Abstract The development of growth factors is very promising in the field of tissue regeneration but specifically designed formulations have to be developed in order to enable such new biological entities (NBEs). In particular, the range of therapeutic concentrations is usually very low compared to other active proteins and the confinement in the target site can be of crucial importance. In-situ forming scaffolds are very promising solutions for minimally invasive intervention in cartilage reconstruction and targeting of NBEs. In this work injectable, in-situ forming gels of a temperature responsive partially degalactosylated xyloglucan (Deg-XG) incorporating the growth factor FGF-18 are fo…

Construction of Spirooxindole Analogues Engrafted with Indole and Pyrazole Scaffolds as Acetylcholinesterase Inhibitors

2021

Twenty-five new hits of spirooxindole analogs 8a–y engrafted with indole and pyrazole scaffolds were designed and constructed via a [3+2]cycloaddition (32CA) reaction starting from three components: new chalcone-based indole and pyrazole scaffolds 5a–d, substituted isatins 6a–c, and secondary amines 7a–d. The potency of the compounds were assessed in modulating cholinesterase (AChE) activity using Ellman’s method. Compounds 8i and 8y showed the strongest acetylcholine esterase inhibition (AChEI) with IC50 values of 24.1 and 27.8 μM, respectively. Molecular docking was used to study their interaction with the active site of hAChE. peerReviewed

Partial data inverse problems for Maxwell equations via Carleman estimates

2015

In this article we consider an inverse boundary value problem for the time-harmonic Maxwell equations. We show that the electromagnetic material parameters are determined by boundary measurements where part of the boundary data is measured on a possibly very small set. This is an extension of earlier scalar results of Bukhgeim-Uhlmann and Kenig-Sj\"ostrand-Uhlmann to the Maxwell system. The main contribution is to show that the Carleman estimate approach to scalar partial data inverse problems introduced in those works can be carried over to the Maxwell system.

Development of an lbuprofen-Releasing Biodegradable PLA/PGA Electrospun Scaffold for Tissue Regeneration

2009

Our aim was to develop a biodegradable fibrous dressing to act as a tissue guide for in situ wound repair while releasing Ibuprofen to reduce inflammation in wounds and reduce pain for patients on dressing changes. Dissolving the acid form of Ibuprofen (from 1% to 10% by weight) in the same solvent as 75% polylactide, 25% polyglycolide (PLGA) polymers gave uniformly loaded electrospun fibers which gave rapid release of drug within the first 8 h and then slower release over several days. Scaffolds with 10% Ibuprofen degraded within 6 days. The Ibuprofen released from these scaffolds significantly reduced the response of fibroblasts to major pro-inflammatory stimulators. Fibroblast attachment…

In vitro and in vivo characterization of porcine acellular dermal matrix for gingival augmentation procedures

2013

Recently, porcine acellular dermal matrix (PADM) has been proposed as a possible alternative to autogenous grafts in periodontal plastic surgery. The aim of the present study was to investigate the in vitro responses of four different oral cell lines cultured on a novel PADM. Furthermore, tissue reaction to PADM was evaluated histologically after subcutaneous implantation in mice.Human gingival fibroblasts (HGF), human osteoblast-like cells, human umbilical vein endothelial cells and human oral keratinocytes (HOK) were cultured and transferred on to the PADM. A tissue culture polystyrene surface served as the control. The viability of all tested cell lines on PADM was measured by using the …

Biomimetic Alginate/Gelatin Cross-Linked Hydrogels Supplemented with Polyphosphate for Wound Healing Applications

2020

In the present study, the fabrication of a biomimetic wound dressing that mimics the extracellular matrix, consisting of a hydrogel matrix composed of non-oxidized and periodate-oxidized marine alginate, was prepared to which gelatin was bound via Schiff base formation. Into this alginate/oxidized-alginate-gelatin hydrogel, polyP was stably but reversibly integrated by ionic cross-linking with Zn2+ ions. Thereby, a soft hybrid material is obtained, consisting of a more rigid alginate scaffold and porous structures formed by the oxidized-alginate-gelatin hydrogel with ionically cross-linked polyP. Two forms of the Zn-polyP-containing matrices were obtained based on the property of polyP to f…

Glaciotektoniskās struktūras karjerā “Grantskalni-Sprinčupe”

2019

Bakalaura darbs “Glaciotektoniskās struktūras karjerā “Grantskalni-Sprinčupe”” ir veltīts glaciotektonisko struktūru, galvenokārt, kroku pētīšanai Rietumkursas augstienes Kurmāles paugurainē. Papildus tam ir dokumentēti arī karjerā novērotie lūzumi un vairākās vietās veikti oļu garenasu mērījumi. Pētījuma izstrādes gaitā ir veikta glaciotektonisko struktūru izpēte, kurā ietilpst atsegumu attīrīšana, to foto dokumentācija, galveno elementu uzmērīšana un datu apstrāde. Pētījuma noslēgumā veikta iegūto rezultātu interpretācija un izteikti secinājumi par iespējamajiem kroku veidojošajiem spriegumu virzieniem un Usmas ledus loba ietekmi uz glaciotektonisko struktūru veidošanos.