porosity

..Their porosity, compressive mechanical properties and biological response were evaluated...

b>Porosity and pore size of biomaterial scaffolds play a critical role in bone formation in vitro and in vivo...

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..Formation of hydroxyapatite on the surface of composites, as an indication of their bioactivity, was recorded by EDXA, X-ray diffractometry and confirmed by Raman spectroscopy...

..We envision that these MSN-based systems have a great potential for a variety of drug delivery applications, such as the site-specific delivery and intracellular controlled release of drugs, genes, and other therapeutic agents...

..Highly interconnected porosity was achieved by means of the salt-leaching technique using a mixture of sodium chloride and sodium bicarbonate as ..

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..microCT) analysis demonstrated the capability to fabricate three-dimensional structures with an interconnected porosity and pore sizes suitable for tissue ingrowth and vascularization...

..In addition to their high loadings, they also potentially associate therapeutics and diagnostics, thus opening the way for theranostics, or personalized patient treatments...

..In addition to the presentation of the morphologies of the fabricated scaffolds, preliminary data of cell culture on them are as well included in the present work...

..A sealing effect against the migration of PE particles was found for both Fi and Pl implants in exact fit...

..Advantages and limitations of these materials are analysed along with various architectural parameters of scaffolds important for bone tissue engineering, e.g. porosity, pore size, interconnectivity and pore-wall microstructures.

..The importance of diffusion in scaffolds and how it is influenced by porosity, permeability, architecture, and nutrient mixing has been emphasized...

..In fact, porous materials now seem set to contribute to developments in areas ranging from microelectronics to medical diagnosis...

Increases in cortical porosity (Ct.Po) and decreases in cortical thickness (Ct.Th) are associated with increased bone fragility...

..Open questions concerning the mechanistic understanding of the plant cuticular transport barrier and the role the plant cuticle plays in ensuring the survival and reproductive success of an individual plant are indicated...

..The goal of this study was to characterize intracortical porosity in a cross-sectional patient cohort using novel quantitative computational methods applied to high-resolution ..

This study investigated the relative contributions of pore size and pore density (number of pores per mm2) to porosity in the midshaft of the human femur...

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..radiation allowed visualization of the 3D cortical bone microarchitecture and measurement of intracortical porosity of femoral neck cortical bone specimens from 19 female cadavers imaged at 10.13-microm resolution...

..These fiber diameters were around 411 +/- 158 to 856 +/- 157 nm, and the pore size and porosity around 5-35 microm and 76-93%, respectively...

..The possibility of changing the structure and properties of the gels by adding different solutes could open up new applications for these materials, for example, chromatography applications...

..The mechanism includes a negative feedback that makes peptide-induced pores stable with a well defined size, contrary to the suggestion that peptides disintegrate the membrane in a detergent-like manner...

..Composites provide a partial solution to this problem, although their bioactive and degradation properties are not ideal, therefore novel nanocomposites are needed. The route to these potentially ideal materials is described...

Quantification of porosity and degree of mineralization of bone facilitates a better understanding of the possible effects of adaptive bone remodelling and the possible consequences for its mechanical properties...

..05). Taken together, newly developed 3-D poly(trimethylenecarbonate-co-epsilon-caprolactone)-block-poly(p-dioxanone) scaffold is a promising candidate for bone regeneration...

..In the future, in vivo applications will shed more light on the performance of gradient-based mechanical integrity and signal delivery strategies compared to traditional tissue engineering approaches...

..1-2.5 MPa)) were assessed by standardized impaction and a confined compression test. Loaded samples were used for particle release analysis...

..Along this line, this study aimed at the design of porous scaffolds with controlled porosity and pore size distribution from blends of poly(epsilon-caprolactone) (PCL) and thermoplastic gelatin (TG), a ..

..According to the author's knowledge, this is the first report of a systematic study and determination of the K(d) value for immobilized hepatocytes, incorporating a wide range of cell concentrations within the alginate matrix...

..Based on the simulation of a mutated peptide and the effects of small external electric fields, we conclude that electrostatic forces play a crucial role in the process of pore formation...

..The HA/PU composite scaffold with a high HA content of about 60 wt% has a porosity of more than 78% and a pore size from 100 microm to 800 microm...

..From the envelope and the skeletal volume of the microspheres the porosity was calculated...

..network of interconnected pores (300-900 microm); in addition, a random and not necessarily connected porosity is generated, yielding a hierarchical porous architecture from the macro to the molecular scale...

..The pore size distribution, porosity, pore interconnectivity, and spatial pore heterogeneity of the 3D PCLF scaffolds were assessed using micro-..

..Prior work has shown a strong correlation between porosity, measured as the change in the volume of pores accessible to a cellulase-sized molecule, and the initial ..

..We estimated the radius of these pores, which increases with an increase in magainin 2 concentration. On the basis of these data, we propose a hypothesis on the mechanism of magainin 2-induced pore formation...

..It was shown that PLGA-HAP composites support osteoblast growth and vitality, paving the way for applications as bone tissue engineering scaffolds...

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..Two different surgical implantation techniques in a sheep model were evaluated...

..After further post-processing in a three-dimensional network, these nanofibers can potentially be used as scaffolds for tissue engineering...

..The combined effect of BMP-2, a potent osteoinductive growth factor, and multiscale porosity has yet to be investigated...

..The scaffolds also have textural porosity in the mesopore range (10-20 nm). The scaffolds were sintered at 600, 700, 800 and 1000 degrees C...

..This model is then homogenized to give a continuum description in terms of the vascular density. The resulting equations comprise a double porous medium with coupled Darcy flow through the interstitium and vasculature...

..Measurements of rho(m) of specimens of unequal size or quantities of bone mineral must be interpreted with caution unless appropriate steps are taken to minimize these potential artifacts...

..Thus, high initial microparticle porosities do not only lead to increased drug mobilities, but can also fundamentally alter the underlying mass transport mechanisms...

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..A homogeneous agarose (HA) bead was also produced and modified with DEAE for comparison. It was found that the porosity of SA-DEAE was about 6% larger than that of HA-DEAE...

..the homogeneous expansion of pores within the polymer hydrogel matrices, leading to well-interconnected high porosity. The mechanical properties of the hydrogels were influenced by the cross-linking density and porous structure...

..It was demonstrated that it is possible to manufacture parts with inner channels with a dimension down to 450 microm and wall structures with a thickness down to 330 microm. The mechanical strength of dense test parts is up to 22 MPa...

..We present a method to create a microporous, nanofibriliar fibrin scaffold that has controllable pore size, porosity, and microstructure for applications in tissue engineering...

..The foams prepared combined a very high interconnectivity and porosity with the desired compression modulus...

..a microfilter, the excess lipid layer on both sides of the lipophilic filter increases the "apparent" porosity, epsilon(a), of the filter...

..We demonstrated the feasibility of preparing rabbit autologous hybrid materials following a process for controlling culture conditions, cell characterization and cell/material association...

Blocks of two porous synthetic hydroxyapatites (HA) with porosity fraction of 30-40 and 50-60 vol%, respectively and a coralline derived porous HA were evaluated in vitro in presence of the osteogenic line MC3T3-E1 and of L929 fibroblasts...

..Evidence suggests that the formation of such lipidic pores is a major mechanism for alpha-pore-forming proteins, including apoptosis-regulator Bax...

..Thus, further work is required if these continuum theories are to be reliably salvaged for quantitative studies of biological ion channels in all situations...

..This paper reviews the preparation, chemistry, and properties of electrochemically prepared porous Si or SiO2 hosts relevant to drug delivery applications...

..Therefore, CaP/PLGA composites can be regarded as biocompatible biomaterials with potential for bone tissue engineering and advantageous possibilities of the microparticles regarding material porosity.

..Finally, there was significantly greater bone-to-implant contact within the sinter neck regions of the Ca-P-coated implants...

..g. scaffold porosity, Young's modulus, and dissolution rate...

..In the scaffolds, having much thinner pore walls, heterogenous degradation due to the autocatalytic effect was not observed...

..width, and trabecular bone volume seemed to more than compensate for the dose-dependent increase in cortical porosity. Beneficial effects of teriparatide treatment on the proximal femur persisted beyond the treatment period and may ..

Hydroxyapatite (HA) scaffolds with a 3-D periodic architecture and multiscale porosity have been fabricated by direct-write assembly...

..Furthermore, we demonstrate that the chemical sensing ability can be tuned via layer thickness, composition and surface properties...

..Modified alumina membranes reduce >99% of 0.4 mM 4-nitrophenol at linear flow rates of 0.98 cm/s, and the modification process is also applicable to track-etched polycarbonate supports...

..The nanopore arrays were characterized using transmission electron microscopy (TEM) after the FIB drilling...

..In conclusion, this approach provides a simple one-step process to fabricate surface-modified collagen-like NF-PLLA scaffolds, which have improved cell adhesion and proliferation...

..These advantageous properties indicate that the blended chitosan/PHB material is promising for tissue engineering applications...

..The degree of particle fusion and porosity were influenced by the laser processing parameters, hence control can be attained by varying these parameters...

..and open-cellular pore structures with almost same surface and interior porosities (pore size, 200-300 microm; porosity, about 90%)...

..The ability to micro-pattern cells on porous scaffolds may facilitate the transfer of micro-technology from simple 2D substrates to complex 3D architectures, allowing for tight control over cellular organization in fabricated tissues...

..Such systems have wide application prospects in varied fields such as nanotechnology and engineering...

..Conventional sol-gel processing yields pores an order of magnitude larger. Gelling time was also reduced from many hours to a few minutes, without using a gelling agent, and large crack-free monoliths were synthesized within 1 week...

..Introduction of less than 20wt.% of BGC nanoparticles did not remarkably affect the porosity of PLLA foam. However, as the BGC content increased to 30wt...

..This study has demonstrated that the pore size and structure of the supercritical PDLLA and PLGA scaffolds can be tailored by careful control of processing conditions...

Scaffold with controlled porosity constitute a cornerstone in tissue engineering, as a physical support for cell adhesion and growth...

..Optimizing their mechanical properties, the formed hydrogels represent promising candidates as matrices for soft tissue reconstruction...

Films and sponges were prepared from a solution of Poly(epsilon-caprolactone) (PCL) in tetrahydrofuran (THF). The porosity, crystallinity, and mechanical properties of the samples were studied...

..and a dodecylated US-tube (F-US-tube) nanocomposite] in order to evaluate the effects of material composition and porosity on scaffold pore structure, mechanical properties, and marrow stromal cell culture...

..This study is specifically concerned with the effects these nanotopographies have on adhesion formation in S-phase osteoblasts as identified by BrdU incorporation. Nanopits were found to reduce cellular spreading and adhesion formation...

..For high CHD contents, coatings consist of CHD crystals coated by nano-crystalline hydroxyapatite...

..In contrast, HaCaT keratinocytes cultured under identical conditions using viscose rayon scaffolds occupied very much smaller void distances of 50-80 microm predominantly by stratification...

..In addition, high FN and LM concentrations affected collagen fibre assembly and structure and induced drastic effects on rheological and transport properties...

..Such scaffolds should therefore be further developed as systems for bone tissue regeneration...

..Microchannels are neatly incorporated via an indirect solid freeform fabrication (SFF) process, which could aid in reducing the different constraints commonly observed with other scaffolds...

..The aim of this study was to investigate the influence of physical parameters such as porosity and fibre diameter on the degradation of chitosan fibre-mesh scaffolds, as a possible way of tailoring the ..

..The porosities obtained in the prepared scaffolds were between 76 to 86%. Moreover, the highest porosity of 86% was obtained with minimum fraction of total porogen...

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..Keratinocytes optimally attached to 3-microm-pore films due to a combination of greater pore numbers (porosity), a greater circumference of the pore edge per unit surface area, and greater frequency of flat surface areas for ..

..Spectroscopic ellipsometry is utilized to quantify changes in both the film thickness and porosity; these properties provide insight into the dissolution mechanism...

..moulding combined with salt leaching, and freeze-drying, this process allows excellent control over pore size and porosity and yields scaffolds with a much more homogeneous pore morphology...

..Thus, PES is a substrate for the growth of many different types of human cells and may be a useful scaffolding material for tissue engineering...

..Several design parameters including construct architecture, porosity, degradability, and cell source were examined...

..The investigation showed that this material can be used to make matrices for in vitro proliferous cells. The investigated properties of poly-(3HB) and poly(3HB-co-3HV) films proved to be fundamentally similar...

..The leukocyte elimination ratio depends on pore structures (size and depth) as well as recovery of platelet and erythrocyte...

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..It was concluded that for BSA whose Stoke's diameter is ca. 3.55 nm the minimum pore size of about 45 nm or larger was required for a sufficient adsorption capacity...

..It was shown that the simple two-component SiO2-CaO gel-glass powder is bioactive with comparable dissolution rates as the clinically used melt-derived 45S5 Bioglass powder and extensively studied sol-gel-derived 58S gel-glass powder...

..the processing conditions, the pore size can be altered from sub-micron range to a few hundred microns and the porosity varied from 70% to 97%...

..may self-crosslink in the absence of a crosslinking agent, (2) the use of degradable hydrogel microspheres as the porosity generating method would both improve the scaffold's injectability and eliminate the step of solid porogen ..

..25:1, 1.33:1 and 1.5:1 on in vitro and in vivo resorption. 3) To develop 3D interconnected tailored porosity CaP structures using rapid prototyping, with an average 300 microns pore size, and, 30 and 60 volume % porosity ..

..Silk scaffold fabrication methods, porosity, degradation rates, and added growth factor peptides, will be systematically evaluated...

..will be tested using a three-dimensional cell/polymer model developed in our laboratory to determine the optimal porosity and pore size of hydrogel scaffolds for maximum bone formation in vitro...

..These poor behaviors are primarily attributed to the polymer's lack of integrin-specific ligands and proper porosity. A fibrin polymer is capable of engaging many integrins on mostly inflammatory cells;however the lack of ..

..These poor behaviors are primarily attributed to the polymer's lack of integrin-specific ligands and proper porosity. A fibrin polymer is capable of engaging many integrins on mostly inflammatory cells;however the lack of ..

..This study will utilize supercritical fluid technology for controlling particle porosity, LEDGF release, and residual solvent content in microparticles and immunochemical methods for assessing retinal ..

..It creates a unique, 3- dimensional, open-cell porosity most useful when made in silicone rubbers...

..25:1, 1.33:1 and 1.5:1 on in vitro and in vivo resorption. 3) To develop 3D interconnected tailored porosity CaP structures using rapid prototyping, with an average 300 microns pore size, and, 30 and 60 volume % porosity ..

..25:1, 1.33:1 and 1.5:1 on in vitro and in vivo resorption. 3) To develop 3D interconnected tailored porosity CaP structures using rapid prototyping, with an average 300 microns pore size, and, 30 and 60 volume % porosity ..

..The impact of stent graft porosity on the transmission of pressure to the aneurysm will also be studied...

..will examine changes in cigarette design (blend, tobacco weight, circumference, ventilation, paper citrate, paper porosity, rod moisture) due to the LIP laws, and whether these changes significantly affect ignition propensity or thermal ..

..Aim 1: Computationally design and fabricate scaffolds architectures from HA/TCP, PLLA, and PCL at a single porosity of 60% with maximal and sub-maximal permeability Specific Aim 2: Determine elastic modulus and ultimate strength ..

..will examine changes in cigarette design (blend, tobacco weight, circumference, ventilation, paper citrate, paper porosity, rod moisture) due to the LIP laws, and whether these changes significantly affect ignition propensity or thermal ..

..Aim 1: Computationally design and fabricate scaffolds architectures from HA/TCP, PLLA, and PCL at a single porosity of 60% with maximal and sub-maximal permeability Specific Aim 2: Determine elastic modulus and ultimate strength ..

..distribution of many globular proteins depends on the detailed structure of the nucleoid, especially on its porosity to proteins of different size and charge...

..Phase I has two Specific Aims: 1) identify a novel approach to create porosity and high Ti-content at the surface, and 2) demonstrate desirable surface morphology and biocompatibility for ..

..implants, such as Apligraft TM (Organogenesis), do not hold protein therapeutics because of the required porosity of these materials...

..thinning of the cortex is partially offset by periosteal expansion, this process is accompanied by increased porosity. It is well known that increased porosity, a hallmark of enhanced bone turnover, significantly contributes to the ..

..will allow us to definitively determine whether increased stiffness of SC cells leads to a decreased inner wall porosity and consequently the increased outflow resistance characteristic of most cases of POAG...

..will allow us to definitively determine whether increased stiffness of SC cells leads to a decreased inner wall porosity and consequently the increased outflow resistance characteristic of most cases of POAG...

..of shape templates will be prepared, which use will enable the preparation of uniform 3 mu m beads with high porosity, well-defined regular surfaces, and tunable chemistry...

..will allow us to definitively determine whether increased stiffness of SC cells leads to a decreased inner wall porosity and consequently the increased outflow resistance characteristic of most cases of POAG...

..volumetric bone mineral density (BMD), and assessment of bone microstructural characteristics, such as cortical porosity and trabecular connectivity ("noninvasive bone biopsy")...

..volumetric bone mineral density (BMD), and assessment of bone microstructural characteristics, such as cortical porosity and trabecular connectivity ("noninvasive bone biopsy")...