Hierarchical Structure of Porosity in Cortical and Trabecular Bones

2012 ◽  
Vol 1420 ◽  
Author(s):  
Ekaterina Novitskaya ◽  
Elham Hamed ◽  
Jun Li ◽  
Zherrina Manilay ◽  
Iwona Jasiuk ◽  
...  
Keyword(s):  
Hierarchical Structure ◽  
Mechanical Response ◽  
Bone Structure ◽  
Major Effect ◽  
Micro Computed Tomography ◽  
Mineral Phases ◽  
The Hierarchical Structure ◽  
Trabecular Bones ◽  
Main Components ◽  
Insight Into

ABSTRACTIn this paper the amount and morphology of cortical and trabecular bone porosities were estimated using optical microscopy and micro-computed tomography technique. The hierarchical structure of porosity at different structural scales spanning from a single lacuna (sub-microscale) to trabecular or cortical bone levels (mesoscale) was characterized and described. This study was conducted by using samples of untreated, deproteinized and demineralized bones, to obtain better insight into the bone structure and porosities. The motivation of this work is that the porosity in bone has a major effect on its mechanical response, yet it is often neglected in bone models. Investigations of the mechanical properties of bone and its main components (collagen and mineral phases), complemented by modeling, are of importance in orthopedics.

scholarly journals ESSENTIAL CHARACTERISTICS OF THE ECONOMIC SECURITY OF THE STATE AND ITS MAIN COMPONENTS

World Science ◽  
2019 ◽  
Vol 3 (11(51)) ◽  
pp. 4-8
Author(s):  
Golovko Vladyslav
Keyword(s):  
Hierarchical Structure ◽  
National Economy ◽  
Negative Impact ◽  
Economic Security ◽  
The State ◽  
Historical Aspects ◽  
The Hierarchical Structure ◽  
Main Components ◽  
High Level ◽  
Social Demographic

The historical aspects of the development of economic security are considered. The hierarchical structure of economic security was formed according to the results of the study. Each level is characterized separately. The essence of the concept of “economic security of the state” has been defined. Economic security of the state should be understood as such a condition of the national economy, in which it is possible to provide a high level of protection of the interests of each of its subjects from the negative impact of external and internal threats. The main components of the economic security of the state are identified, which include: financial, social, demographic, innovative, investment, food, energy and technological. The process of achieving a high level of economic security of the state by ensuring security for each of its components is presented.

Parafia unicka w Rachaniach do 1811 roku/ The Uniate Parish in Rachanie until 1811

2012 ◽  
Vol 67 (2) ◽  
Author(s):  
Janusz Adam Frykowski
Keyword(s):  
Hierarchical Structure ◽  
Geographical Location ◽  
Historical Sources ◽  
Holy Communion ◽  
The Hierarchical Structure ◽  
History Of ◽  
The Church ◽  
Ancillary Equipment

AbstractThe following paper depicts the history of Saint Simeon Stylites Uniate Parish in Rachanie since it became known in historical sources until 1811- that is the time it ceased to be an independent church unit. The introduction of the article contains the geographical location of the parish, its size and the position within the hierarchical structure of the Church. Having analysed post-visit inspection protocols left by Chelm Bishops, the appearance as well as fittings and ancillary equipment of the church in Rachanie in that particular period are reported. Moreover, the list of 4 local clergymen is recreated and their benefice is determined. As far as possible, both the number of worshipers and the number of Holy Communion receivers is determined.

scholarly journals Topical co‐administration of zoledronate with recombinant human bone morphogenetic protein-2 can induce and maintain bone formation in the bone marrow environment

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hideki Ueyama ◽  
Yoichi Ohta ◽  
Yuuki Imai ◽  
Akinobu Suzuki ◽  
Ryo Sugama ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Bone Formation ◽  
Bone Structure ◽  
Precursor Cells ◽  
The Other ◽  
Bone Morphogenetic Protein 2 ◽  
New Bone Formation ◽  
Micro Computed Tomography ◽  
Mineral Density ◽  
Left Femur

Abstract Background Bone morphogenetic proteins (BMPs) induce osteogenesis in various environments. However, when BMPs are used alone in the bone marrow environment, the maintenance of new bone formation is difficult owing to vigorous bone resorption. This is because BMPs stimulate the differentiation of not only osteoblast precursor cells but also osteoclast precursor cells. The present study aimed to induce and maintain new bone formation using the topical co-administration of recombinant human BMP-2 (rh-BMP-2) and zoledronate (ZOL) on beta-tricalcium phosphate (β-TCP) composite. Methods β-TCP columns were impregnated with both rh-BMP-2 (30 µg) and ZOL (5 µg), rh-BMP-2 alone, or ZOL alone, and implanted into the left femur canal of New Zealand white rabbits (n = 56). The implanted β-TCP columns were harvested and evaluated at 3 and 6 weeks after implantation. These harvested β-TCP columns were evaluated radiologically using plane radiograph, and histologically using haematoxylin/eosin (H&E) and Masson’s trichrome (MT) staining. In addition, micro-computed tomography (CT) was performed for qualitative analysis of bone formation in each group (n = 7). Results Tissue sections stained with H&E and MT dyes revealed that new bone formation inside the β-TCP composite was significantly greater in those impregnated with both rh-BMP-2 and ZOL than in those from the other experimental groups at 3 and 6 weeks after implantations (p < 0.05). Micro-CT data also demonstrated that the bone volume and the bone mineral density inside the β-TCP columns were significantly greater in those impregnated with both rh-BMP-2 and ZOL than in those from the other experimental groups at 3 and 6 weeks after implantations (p < 0.05). Conclusions The topical co-administration of both rh-BMP-2 and ZOL on β-TCP composite promoted and maintained newly formed bone structure in the bone marrow environment.

Default Logic Models of Certain Inheritance Systems with Exceptions

1993 ◽  
Vol 18 (2-4) ◽  
pp. 129-149
Author(s):  
Serge Garlatti
Keyword(s):  
Hierarchical Structure ◽  
Formal Semantics ◽  
Sufficient Conditions ◽  
Nonmonotonic Reasoning ◽  
Default Logic ◽  
Representation Systems ◽  
The Hierarchical Structure ◽  
Necessary And Sufficient ◽  
Structure Of Knowledge ◽  
Made In

Representation systems based on inheritance networks are founded on the hierarchical structure of knowledge. Such representation is composed of a set of objects and a set of is-a links between nodes. Objects are generally defined by means of a set of properties. An inheritance mechanism enables us to share properties across the hierarchy, called an inheritance graph. It is often difficult, even impossible to define classes by means of a set of necessary and sufficient conditions. For this reason, exceptions must be allowed and they induce nonmonotonic reasoning. Many researchers have used default logic to give them formal semantics and to define sound inferences. In this paper, we propose a survey of the different models of nonmonotonic inheritance systems by means of default logic. A comparison between default theories and inheritance mechanisms is made. In conclusion, the ability of default logic to take some inheritance mechanisms into account is discussed.

scholarly journals Stepwise collapse of a giant pore metal–organic framework

2021 ◽  
Vol 50 (14) ◽  
pp. 5011-5022 ◽  
Author(s):  
Adam F. Sapnik ◽  
Duncan N. Johnstone ◽  
Sean M. Collins ◽  
Giorgio Divitini ◽  
Alice M. Bumstead ◽  
...  
Keyword(s):  
Distribution Function ◽  
Hierarchical Structure ◽  
Pair Distribution Function ◽  
Function Analysis ◽  
Metal Organic Framework ◽  
Defect Engineering ◽  
Structural Collapse ◽  
The Hierarchical Structure ◽  
Metal Organic ◽  
Organic Framework

Defect engineering is used to augment the porosity of MIL-100. Incorporation of defects leads to structural collapse and ultimately causes amorphisation. Pair distribution function analysis reveals a stepwise collapse of the hierarchical structure.

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