Novel Bio ceramic Scaffolds for Regenerative Medicine

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Calcium phosphate ceramics have been used as synthetic grafts for bone repair. This family of alloplastic grafts is an alternative to allografts (from other individuals from the same specie), auto grafts (from the same individual) or xenografts (from individuals from other species). Sintered bovine bone is basically composed mainly by hydroxyapatite (HA), Ca10(PO4)6(OH)2 but chemical analyses indicate the presence of Mg. Chemical and heat treatments are generally required to eliminate biological hazard.

Novel Bio ceramic Scaffolds

However, the more crystalline hydroxyapatite, the less resorbable the product is. An approach to have a highly crystalline and still resorbable material is to use additions of alpha or beta tricalcium phosphate, Ca3(PO4)2 , (TCP). The addition of fractions of some bioactive glasses to hydroxyapatite has shown to be effective in promoting its decomposition to tricalcium phosphate. In addition, glass reinforced hydroxyapatite composite are materials with higher compressive strength due to liquid phase sintering. In this study, novel scaffolds based on hydroxyapatite and tricalcium phosphate are presented.

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Morphological Relationship between Nerve Fibers and Melanocytes in the Epidermis of Melasma

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Melanocytes are cells of neural crest origin. In the human epidermis, they form a close association with keratinocytes via their dendrites. Melanocytes are well known for their role in skin pigmentation, and their ability to produce and distribute melanin has been studied extensively. A close contact between melanocytes and nerve fibers in the epidermis has been demonstrated in normal human skin. In patho physiology of certain dermatoses interactions between the neural and immune systems play an important role.

Morphological

In this study, we investigated the intraepidermal nerve fibers and their contacts with melanocytes in the lesions of melasma using double labeled immune fluorescency and confocal laser scanning microscopy. We found that the percentage of contacts between intraepidermal nerve fibers and melanocytes in the lesion of melasma were 74%, significantly more than the 42% in the normal controls (p<0.05). The difference in the number of neural-melanocytic contacts between the lesional and normal-appearing skin of the melasma patients was also statistically significant (p<0.05). Melasma is an acquired circumscribed facial hyperpigmentation commonly seen in Asian women. A number of anecdotal clinical observations have shown that when the melasma patients are physically exhausted or emotionally distressed, the facial skin hyperpigmentation becomes more obvious.

Network Analysis and the Network Organization in Organization Research

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The ‘Network Perspective’ has emerged as an important influence in organization and management research over the last few decades. The network perspective in this context has no specific definition; instead it generally encompasses the notion of networks and the techniques of network analysis, both of which have long histories in sociology. In this paper we examine empirical articles which use a network perspective in organization studies to see how the use of network analysis and how the concept of ‘network organizations’ is addressed.

Network Organization

It is argued that the use of network analysis and the concept of ‘network organizations’ have little overlap in the literature. The findings show that the use of network analysis techniques is firmly established; however it is not used in investigating network organizations. The literature addressing network organizations is largely theoretical with only a few qualitative empirical studies. Several reasons for the lack of empirical research on network organizations are proposed.

General strength exercise

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General strength exercises are the physical exercises that are used in overall body conditioning. They are not directly related to the specific actions seen in a specific sport (i.e., strengthening the muscles as they are used in a specific sport and increasing an athlete’s functional potential for improved performance).The overhead press exercise which is used by runners can illustrate the concept of a general strength exercise. It is a common exercise in which the arms move directly upward overhead. In running, however, the arms move in a forward-backward motion in relation to the trunk.

General strength exercise

Thus, the overhead press is a good exercise for strengthening the shoulders and arms, but, even though it uses some of the same muscles that are involved in running, it is not directly related to running. If an athlete has weak shoulders this exercise can improve strength capabilities which may indirectly help an athlete’s arms during a run. This exercise is not, however, as effective as an exercise in which the arm and shoulder movements duplicate the exact action (pathway) seen in running. This is known as a specialized exercise. An example of a specialized exercise for the shoulders is driving the arm from behind the body to in front of the body in the same pathway and in the same range of motion as seen in the running stride.

Contact and Joint Forces Modeling and Simulation of Crawler-formation Interactions

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Cable shovels are used in surface mining operations to achieve economic bulk production capacities. The service life of the  rawlers and their shoes define shovel reliability, maintainability, availability and efficiency. The crawler track-terrain  interaction generates high time-fluctuating contact forces that result in stress buildup, crack and fatigue failure of    wler shoes. In addition, the link pins that connect two crawler shoes can exert large fluctuating pin loads on shoe lugding to shoe breakage.

Crawler-formation Interactions

This paper addresses fundamental research into contact forces acting on crawler shoes, joint forces generated in the link pin and total deformation of the formation during shovel propel. During propel, the crawler track is controlled by two drive constraints that cause the crawler to follow straight or turning motions. A virtual prototype simulator of the crawler-terrain interaction dynamics is developed and simulated within the MSC ADAMS environment. The simulation results show that the average penetration depth for different crawler shoes is within the range of 5.9 and 6.7 cm for both types of driving constraints.

Product Donations in Cause-Related Marketing

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The existing literature on Cause-Related Marketing (CRM) deals primarily with monetary donations, though many companies perform CRM campaigns that donate products. When firms donate products through CRM campaigns, there can be two types of donation: donating campaigned product itself and donating different product from the campaigned product. First, the study investigates factors firms should consider when donating the promoted product through the CRM campaign.

Product Donations

Product type (frivolous vs. practical) and consumer characteristics (independent vs. interdependent self-construal) are introduced to explain consumer evaluations of the campaigns. The authors find that interdependent consumers have a more positive attitude toward campaigns of a practical product whereas independent consumers prefer campaigns of a frivolous product. Practical and academic implications are discussed; further, to add more practical implications for manufacturers of frivolous products, the fit between the promoted product and donated product was investigated in cases where the firm intends to donate a practical product.

Melanoma

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MelanomaIpilimumab, used in combination with radiotherapy, electro chemotherapy, or internal radiotherapy, may significantly prolong overall survival in patients with melanoma compared with treatment with ipilimumab.

A lesion is any abnormality in the tissue of an organism, usually caused by disease or trauma. Lesion is derived from the Latin word laesio meaning injury. There are numerous types of lesions with different naming classifications. Lesions can be categorized according to whether or not they are caused by cancer.