The Minimal Total Irregularity of Graphs

In \cite{2012a}, Abdo and Dimitov defined the total irregularity of a graph $G=(V,E)$ as \hskip3.3cm $\rm irr_{t}$$(G) = \frac{1}{2}\sum_{u,v\in V}|d_{G}(u)-d_{G}(v)|,$ \noindent where $d_{G}(u)$ denotes the vertex degree of a vertex $u\in V$. In this paper, we investigate the minimal total irregularity of the connected graphs, determine the minimal, the second minimal, the third minimal total irregularity of trees, unicyclic graphs, bicyclic graphs on $n$ vertices, and propose an open problem for further research.Comment: 13 pages, 4 figure

High-quality tree structures modelling using local convolution surface approximation

In this paper, we propose a local convolution surface approximation approach for quickly modelling tree structures with pleasing visual effect. Using our proposed local convolution surface approximation, we present a tree modelling scheme to create the structure of a tree with a single high-quality quad-only mesh. Through combining the strengths of the convolution surfaces, subdivision surfaces and GPU, our tree modelling approach achieves high efficiency and good mesh quality. With our method, we first extract the line skeletons of given tree models by contracting the meshes with the Laplace operator. Then we approximate the original tree mesh with a convolution surface based on the extracted skeletons. Next, we tessellate the tree trunks represented by convolution surfaces into quad-only subdivision surfaces with good edge flow along the skeletal directions. We implement the most time-consuming subdivision and convolution approximation on the GPU with CUDA, and demonstrate applications of our proposed approach in branch editing and tree composition

Dexmedetomidine relieves inflammatory response in rats with acute spinal cord injury through IKK/NF-κB signaling pathway

Purpose: To examine the effect of dexmedetomidine (DEX) on inflammatory response in spinal cord damage, and involvement of IKK/NF-κB signaling pathway in the process.Methods: Sixty healthy male Wistar rats were selected and randomly divided into sham, control, IKK inhibition, and DEX groups. Rat hind limb motor function in each group at 1, 24 and 48 h after surgery was determined using Basso Beattie Bresnahan (BBB) method, while Western blot assay was used to evaluate the protein expression levels of IL-1β, IKK and NF-κB in spinal cord tissue.Results: In DEX rat group, neuromotor function at 24 and 48 h, and protein expression level of IL-1β in spinal cord tissue significantly decreased, relative to IKK inhibition group (p < 0.05). There were higher protein expressions of IKK and NF-κB in IKK inhibition and DEX groups than in sham rats, but were lower than the corresponding values for model group (p < 0.05). However, these proteins were significantly downregulated in DEX group, relative to the IKK inhibition rats (p < 0.05).Conclusion: DEX mitigates inflammatory response in rats with acute spinal cord injury via IKK/NF-κB signaling pathway. This provides some ideas for research and development of other drugs for the treatment of acute spinal cord injury

Body mass, Thermogenesis and energy metabolism in Tupaia belangeri during cold acclimation

In order to study the relationship between energy strategies and environmental temperature, basal metabolic rate (BMR), nonshivering thermogenesis (NST), the total protein contents, mitochondrial protein contents, state and state respiratory ability, cytochrome C oxidase activity Ⅲ Ⅳ of liver, heart, diaphragm, gastrocnemius and brown adipose tissue (BAT), serum leptin level and serum thyroid hormone levels were measured in tree shrews (Tupaia belangeri) during cold exposure (5±1oC) for 1 day, 7 days,14days,21 days. The results showed that body mass increased, BMR and NST increased, the change of liver mitochondrial protein content was more acutely than total protein. The mitochondrial protein content of heart and BAT were significantly increased during cold-exposed, however the skeletal muscle more moderate reaction. The state Ⅲ and state Ⅳ mitochondrial respiration of these tissues were enhanced significantly than the control. The cytochrome C oxidase activity with cold acclimation also significantly increased except the gastrocnemius. Liver, muscle, BAT, heart and other organs were concerned with thermoregulation during the thermal regulation process above cold-exposed. There is a negative correlation between leptin level and body mass. These results suggested that T. belangeri enhanced thermogenic capacity during cold acclimation, and leptin participated in the regulation of energy balance and body weight in T. belangeri