Modeling cell layers on complex surfaces using constrained Voronoi diagrams

Author(s):  
Fiona Wood
Author(s):  
C.N. Sun

The present study demonstrates the ultrastructure of the gingival epithelium of the pig tail monkey (Macaca nemestrina). Specimens were taken from lingual and facial gingival surfaces and fixed in Dalton's chrome osmium solution (pH 7.6) for 1 hr, dehydrated, and then embedded in Epon 812.Tonofibrils are variable in number and structure according to the different region or location of the gingival epithelial cells, the main orientation of which is parallel to the long axis of the cells. The cytoplasm of the basal epithelial cells contains a great number of tonofilaments and numerous mitochondria. The basement membrane is 300 to 400 A thick. In the cells of stratum spinosum, the tonofibrils are densely packed and increased in number (fig. 1 and 3). They seem to take on a somewhat concentric arrangement around the nucleus. The filaments may occur scattered as thin fibrils in the cytoplasm or they may be arranged in bundles of different thickness. The filaments have a diameter about 50 A. In the stratum granulosum, the cells gradually become flatted, the tonofibrils are usually thin, and the individual tonofilaments are clearly distinguishable (fig. 2). The mitochondria and endoplasmic reticulum are seldom seen in these superficial cell layers.


2021 ◽  
Vol 9 ◽  
Author(s):  
L. Göttsche ◽  
M. Kool ◽  
R. A. Williams

Abstract We conjecture a Verlinde type formula for the moduli space of Higgs sheaves on a surface with a holomorphic 2-form. The conjecture specializes to a Verlinde formula for the moduli space of sheaves. Our formula interpolates between K-theoretic Donaldson invariants studied by Göttsche and Nakajima-Yoshioka and K-theoretic Vafa-Witten invariants introduced by Thomas and also studied by Göttsche and Kool. We verify our conjectures in many examples (for example, on K3 surfaces).


2007 ◽  
Vol 23 (7) ◽  
pp. 503-511 ◽  
Author(s):  
Shinichi Fukushige ◽  
Hiromasa Suzuki

Algorithmica ◽  
2021 ◽  
Author(s):  
Gill Barequet ◽  
Minati De ◽  
Michael T. Goodrich

2021 ◽  
Vol 96 ◽  
pp. 101746
Author(s):  
Ziyun Huang ◽  
Danny Z. Chen ◽  
Jinhui Xu
Keyword(s):  

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 10
Author(s):  
Suzan M. Hazzaa ◽  
Mabrouk A. Abd Eldaim ◽  
Amira A. Fouda ◽  
Asmaa Shams El Dein Mohamed ◽  
Mohamed Mohamed Soliman ◽  
...  

Intermittent fasting (IF) plays an important role in the protection against metabolic syndrome-induced memory defects. This study aimed to assess the protective effects of both prophylactic and curative IF against high-fat diet (HFD)-induced memory defects in rats. The control group received a normal diet; the second group received a HFD; the third group was fed a HFD for 12 weeks and subjected to IF during the last four weeks (curative IF); the fourth group was fed a HFD and subjected to IF simultaneously (prophylactic IF). A high-fat diet significantly increased body weight, serum lipids levels, malondialdehyde (MDA) concentration, glial fibrillary acidic protein (GFAP) and H score in brain tissue and altered memory performance. In addition, it significantly decreased reduced glutathione (GSH) concentration in brain tissue and viability and thickness of pyramidal and hippocampus granular cell layers. However, both types of IF significantly decreased body weight, serum lipids, GFAP protein expression and H score and MDA concentration in brain tissue, and improved memory performance, while it significantly increased GSH concentration in brain tissue, viability, and thickness of pyramidal and granular cell layers of the hippocampus. This study indicated that IF ameliorated HFD-induced memory disturbance and brain tissue damage and the prophylactic IF was more potent than curative IF.


2021 ◽  
Vol 2 (5) ◽  
Author(s):  
Soroosh Tayebi Arasteh ◽  
Adam Kalisz

AbstractSplines are one of the main methods of mathematically representing complicated shapes, which have become the primary technique in the fields of Computer Graphics (CG) and Computer-Aided Geometric Design (CAGD) for modeling complex surfaces. Among all, Bézier and Catmull–Rom splines are the most common in the sub-fields of engineering. In this paper, we focus on conversion between cubic Bézier and Catmull–Rom curve segments, rather than going through their properties. By deriving the conversion equations, we aim at converting the original set of the control points of either of the Catmull–Rom or Bézier cubic curves to a new set of control points, which corresponds to approximately the same shape as the original curve, when considered as the set of the control points of the other curve. Due to providing simple linear transformations of control points, the method is very simple, efficient, and easy to implement, which is further validated in this paper using some numerical and visual examples.


iScience ◽  
2021 ◽  
Vol 24 (4) ◽  
pp. 102287 ◽  
Author(s):  
Marion C. Bichet ◽  
Wai Hoe Chin ◽  
William Richards ◽  
Yu-Wei Lin ◽  
Laura Avellaneda-Franco ◽  
...  

Animals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 2019
Author(s):  
Salvatore Desantis ◽  
Serena Minervini ◽  
Lorenzo Zallocco ◽  
Bruno Cozzi ◽  
Andrea Pirone

The pig has been increasingly used as a suitable animal model in translational neuroscience. However, several features of the fast-growing, immediately motor-competent cerebral cortex of this species have been adequately described. This study analyzes the cytoarchitecture of the primary motor cortex (M1) of newborn, young and adult pigs (Sus scrofa domesticus). Moreover, we investigated the distribution of the neural cells expressing the calcium-binding proteins (CaBPs) (calretinin, CR; parvalbumin, PV) throughout M1. The primary motor cortex of newborn piglets was characterized by a dense neuronal arrangement that made the discrimination of the cell layers difficult, except for layer one. The absence of a clearly recognizable layer four, typical of the agranular cortex, was noted in young and adult pigs. The morphometric and immunohistochemical analyses revealed age-associated changes characterized by (1) thickness increase and neuronal density (number of cells/mm2 of M1) reduction during the first year of life; (2) morphological changes of CR-immunoreactive neurons in the first months of life; (3) higher density of CR- and PV-immunopositive neurons in newborns when compared to young and adult pigs. Since most of the present findings match with those of the human M1, this study strengthens the growing evidence that the brain of the pig can be used as a potentially valuable translational animal model during growth and development.


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