Morphological Characterization of 3D Porous Scaffolds Based on Portland Cement

2008 ◽  
Vol 396-398 ◽  
pp. 687-690 ◽  
Author(s):  
Alexandra A.P. Mansur ◽  
Herman S. Mansur

There is a constant need for bone substitutes. This work was focused on evaluating morphological characteristics of new bioceramic three-dimensional scaffold for bone tissue engineering based on Portland cement with air-voids introduced by outgassing reaction product from lime and aluminum powder. Pores morphology was observed using scanning electron microscopy (SEM). Bulk density, apparent density, and apparent porosity were measured by Archimedes method. Water absorption by total immersion and by capillarity was also investigated. The results have indicated that cement based scaffolds exhibit a hierarchical structure with interconnected macropores and a micropores framework that indicate potential use of the developed porous materials as bone substitutes.

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Jakub Širc ◽  
Radka Hobzová ◽  
Nina Kostina ◽  
Marcela Munzarová ◽  
Martina Juklíčková ◽  
...  

Biomedical applications such as wound dressing for skin regeneration, stem cell transplantation, or drug delivery require special demands on the three-dimensional porous scaffolds. Besides the biocompatibility and mechanical properties, the morphology is the most important attribute of the scaffold. Specific surface area, volume, and size of the pores have considerable effect on cell adhesion, growth, and proliferation. In the case of incorporated biologically active substances, their release is also influenced by the internal structure of nanofibers. Although many scientific papers are focused on the preparation of nanofibers and evaluation of biological tests, the morphological characterization was described just briefly as service methods. The aim of this paper is to summarize the methods applicable for morphological characterization of nanofibers and supplement it by the results of our research. Needleless electrospinning technique was used to prepare nanofibers from polylactide, poly(ε-caprolactone), gelatin, and polyamide. Scanning electron microscopy was used to evaluate the fiber diameters and to reveal eventual artifacts in the nanofibrous structure. Nitrogen adsorption/desorption measurements were employed to measure the specific surface areas. Mercury porosimetry was used to determine total porosities and compare pore size distributions of the prepared samples.


2021 ◽  
Author(s):  
Diego Cunha Zied ◽  
Wagner G. Vieira Junior ◽  
Douglas M. M. Soares ◽  
Cassius V. Stevani ◽  
Eustáquio S. Dias ◽  
...  

Abstract The mushroom Agaricus subrufescens has been synonymous with Agaricus blazei and Agaricus brasiliensis during the last decades and there has been much discussion with regards to the origin, distribution, and nomenclature of this mushroom. Therefore, we conducted a genetic and morphological characterization of the mycelium and mushroom of four commercial strains currently cultivated in Brazil (ABL CS7, ABL 18/01, ABL 98/11, and ABL 16/01) together with an assessment of their agronomic behavior and compared these results with those of other strains used during the last 15 years. All the A. subrufescens strains characterized here are phylogenetically related to the Americas/Europe specimens, bearing an internal transcribed spacer region of type A (ABL 16/01) or both types A and B (ABL 18/01, ABL 98/11, and ABL CS7). We did not find any correlation between the morphological characteristics of the mycelial colonies and the agronomic behavior of the strains. Strains ABL 98/11 and ABL 16/01 produced the best yields and morphological characteristics for the mushrooms, indicating their high weight, which enhances the commercialization of the mushroom and justifies their longstanding commercial use over the last 15 years.


HortScience ◽  
2018 ◽  
Vol 53 (9) ◽  
pp. 1266-1270 ◽  
Author(s):  
Nader R. Abdelsalam ◽  
Hayssam M. Ali ◽  
Mohamed Z.M. Salem ◽  
Elsayed G. Ibrahem ◽  
Mohamed S. Elshikh

Mango (Mangifera indica L.) is a fruit crops belong to the family Anacardiaceae and is the oldest cultivated tree worldwide. Cultivars maintained in Egypt have not been investigated previously. Mango was first brought to Egypt from South Asia. Morphological and molecular techniques were used to identify the genetic diversity within 28 mango cultivars. SSR and EST-SSR were used for optimizing germplasm management of mango cultivars. Significant variations were observed in morphological characteristics and genetic polymorphism, as they ranged from 0.71% to 100%. High diversity was confirmed as a pattern of morphological and genotypes data. Data from the present study may be used to calculate the mango relationship and diversity currently grown in Egypt.


Zootaxa ◽  
2020 ◽  
Vol 4821 (1) ◽  
pp. 49-70
Author(s):  
ASHOK KUMAR MEENA ◽  
RAJAMANI SWAMINATHAN ◽  
RAJENDRA NAGAR

The present paper deals with a description of two new species of crickets of the subfamily Podoscirtinae (Orthoptera: Gryllidae), Trelleora khasiana sp. nov. and Indotrella maculata sp. nov., from India; besides, some additional morphological characteristics of the already reported species, Indotrella angusta Gorochov, 2003 is also presented. The morphological characterization of these two new species is supported with suitable line diagrams and plates. A checklist of crickets of Podoscirtinae for the Asia-tropical region is included.


2011 ◽  
Vol 493-494 ◽  
pp. 826-831
Author(s):  
A.C.B.M. Fook ◽  
Thiago Bizerra Fideles ◽  
R.C. Barbosa ◽  
G.T.F.S. Furtado ◽  
G.Y.H. Sampaio ◽  
...  

The application of a hybrid composite consisting of biopolymer and calcium phosphate, similar morphology and properties of natural bone, may be a way to solve the problem of the fragility of ceramics without reducing its mechanical properties, retaining the properties of biocompatibility and high bioactivity. This work aims at the preparation and characterization of three-dimensional scaffolds composite HA / biopolymers (chitosan and gelatin). The freeze-drying technique was employed in this study to obtain these frameworks and partial results showed the effectiveness of this method. This involved the study of structural, chemical and morphological frameworks, in order to direct the research suggested the application. The X Ray Diffraction (XRD) and infrared spectroscopy and Fourier transform (FTIR) results confirmed the formation of hydroxyapatite (HA) phase and the presence of characteristic bands of HA and biopolymers in all compositions. The microstructure of the scaffolds study conducted by Scanning Electron Microscopy (SEM) revealed the formation of longitudinally oriented microchannels with interconnected pores. In all compositions the porous scaffolds showed varying sizes and mostly larger than 100μm, and is therefore considered materials with potential for application in bone tissue engineering.


2003 ◽  
Vol 9 (3) ◽  
pp. 171-182 ◽  
Author(s):  
Elizabeth R. Wright ◽  
Vincent P. Conticello ◽  
Robert P. Apkarian

Elastin-mimetic block copolymers were produced by genetic engineering. Genetically driven synthesis permitted control of the final physiochemical characteristics of the block copolymers. We designed BB and BAB block copolymers in which the A-block was hydrophilic and the B-block was hydrophobic. By designing the copolymers in this manner, it was proposed that they would self-assemble into micellar aggregates that, at high concentration, would form thermoreversible hydrogels. To analyze the three-dimensional fine surface morphology of the copolymers, to the resolution level of a few nanometers, we employed cryo-HRSEM. This method provided vast expanses of the specimen in its frozen hydrated state for survey. In our initial cryo-HRSEM studies, we observed the protein filaments and micelles surrounded by lakes of vitreous ice. Upon examination at low and intermediate magnifications, there was an extensive honeycomb-like filamentous network. To delineate the fine morphology of the hydrogel network at high magnification and to greater depths, we cryoetched away unbound water from the sample surface, in high vacuum, prior to chromium deposition. By using this technique, we were able to visualize for characterization purposes the fine fibril networks formed from the micellar aggregates over the surface of the hydrogel.


2014 ◽  
Vol 6 (2) ◽  
pp. 451-456 ◽  
Author(s):  
K. K. Sharma ◽  
U. S. Singh

The genus Trichoderma contains species that are of a great economic importance due to their ability to act as biological control agents against a large variety of fungal plant pathogens. In the present investigation thirty isolates of the Trichoderma sp. were obtained from the rhizosphere soils of different plants at different locations at Nainital, Almora, Udham Singh Nagar, Derhadun, Haridwar and Tehri Garhwal districts of Uttarakhand (India). The isolates were characterized on the basis of their cultural and morphological characteristics. The cultural characteristics included linear growth, colony colour, pigmentation and growth pattern. Morphological characteristics studied were structure, shape and arrangement of conidiophores, phialides and conidia. Out of thirty isolates, 6 isolates namely PB10, PB13, PB23, PB26, PB27 and PB28 were identified as T. virens and remaining 24 isolates as T. harzianum.


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