5,951 research outputs found
Some new applications for heat and fluid flows via fractional derivatives without singular kernel
This paper addresses the mathematical models for the heat-conduction
equations and the Navier-Stokes equations via fractional derivatives without
singular kernel.Comment: This is a preprint of a paper whose final and definite form will be
published in Thermal Science. Paper Submitted 28/ Dec /2016; Revised
20/Jan/2016; Accepted for publication 21/Jan/201
A new fractional derivative without singular kernel: Application to the modelling of the steady heat flow
In this article we propose a new fractional derivative without singular
kernel. We consider the potential application for modeling the steady
heat-conduction problem. The analytical solution of the fractional-order heat
flow is also obtained by means of the Laplace transform.Comment: 1 figur
Medium effects on the selection of sequences folding into stable proteins in a simple model
We study the medium effects on the selection of sequences in protein folding
by taking account of the surface potential in HP-model. Our analysis on the
proportion of H and P monomers in the sequences gives a direct interpretation
that the lowly designable structures possess small average gap. The numerical
calculation by means of our model exhibits that the surface potential enhances
the average gap of highly designable structures. It also shows that a most
stable structure may be no longer the most stable one if the medium parameters
changed.Comment: 4 pages, 4 figure
A novel multifunctional biomedical material based on polyacrylonitrile:preparation and characterization
Wet spun microfibers have great potential in the design of multifunctional controlled release materials. Curcumin (Cur) and vitamin E acetate (Vit. E Ac) were used as a model drug system to evaluate the potential application of the drug-loaded microfiber system for enhanced delivery. The drugs and polyacrylonitrile (PAN) were blended together and spun to produce the target drug-loaded microfiber using an improved wet-spinning method and then the microfibers were successfully woven into fabrics. Morphological, mechanical properties, thermal behavior, drug release performance characteristics, and cytocompatibility were determined. The drug-loaded microfiber had a lobed “kidney” shape with a height of 50 ~ 100 μm and width of 100 ~ 200 μm. The addition of Cur and Vit. E Ac had a great influence on the surface and cross section structure of the microfiber, leading to a rough surface having microvoids. X-ray diffraction and Fourier transform infrared spectroscopy indicated that the drugs were successfully encapsulated and dispersed evenly in the microfilament fiber. After drug loading, the mechanical performance of the microfilament changed, with the breaking strength improved slightly, but the tensile elongation increased significantly. Thermogravimetric results showed that the drug load had no apparent adverse effect on the thermal properties of the microfibers. However, drug release from the fiber, as determined through in-vitro experiments, is relatively low and this property is maintained over time. Furthermore, in-vitro cytocompatibility testing showed that no cytotoxicty on the L929 cells was found up to 5% and 10% respectively of the theoretical drug loading content (TDLC) of curcumin and vitamin E acetate. This study provides reference data to aid the development of multifunctional textiles and to explore their use in the biomedical material field
Bremsstrahlung Radiation as Coherent State in Thermal QED
Based on fully finite temperature field theory we investigate the radiation
probability in the bremsstrahlung process in thermal QED. It turns out that the
infrared divergences resulting from the emission and absorption of the real
photons are canceled by the virtual photon exchange processes at finite
temperature. The full quantum calculation results for soft photons radiation
coincide completely with that obtained in the semi-classical approximation. In
the framework of Thermofield Dynamics it is shown that the bremsstrahlung
radiation in thermal QED is a coherent state, the quasiclassical behavior of
the coherent state leads to above coincidence.Comment: 8 pages, 2 figure
The prevalence of autism spectrum disorders in China: A comprehensive meta-analysis
There are conflicting prevalence estimates of autism spectrum disorders (ASDs) in mainland China (China thereafter). This study is a comprehensive meta-analysis of the pooled prevalence of ASDs in the general population in China. Study investigators independently conducted a systematic literature search of the following databases: PubMed, EMBASE, PsycINFO, China National Knowledge Infrastructure, Chinese biomedical literature service system, and Wan Fang. Studies reporting prevalence of ASDs and autism in Chinese population were identified and analysed using the Comprehensive Meta-Analysis program with the random effects model. Forty-four studies were included in the meta-analysis comprising 2,337,321 subjects of whom 46.66 % were females. The mean age of subjects ranged from 1.6 to 8 years. Based on diagnostic criteria the pooled prevalence of ASDs was 39.23 per 10,000 (95% CI: 28.44-50.03 per 10,000, I2=89.2%); specifically, the prevalence of autism was 10.18 per 10,000 (95% CI: 8.46-11.89 per 10,000, I2=92.5%). Subgroup analyses revealed significant difference in the prevalence of ASDs between genders (72.77 per 10,000 in males vs. 16.45 per 10,000 in females). In conclusion, the prevalence of ASDs and autism in China was found generally lower than those reported in other countries. Further studies are needed to clarify the variation in prevalence
A human motion feature based on semi-supervised learning of GMM
Using motion capture to create naturally looking motion sequences for virtual character animation has become a standard procedure in the games and visual effects industry. With the fast growth of motion data, the task of automatically annotating new motions is gaining an importance. In this paper, we present a novel statistic feature to represent each motion according to the pre-labeled categories of key-poses. A probabilistic model is trained with semi-supervised learning of the Gaussian mixture model (GMM). Each pose in a given motion could then be described by a feature vector of a series of probabilities by GMM. A motion feature descriptor is proposed based on the statistics of all pose features. The experimental results and comparison with existing work show that our method performs more accurately and efficiently in motion retrieval and annotation
Synthesis and evaluation of temperature- and glucose-sensitive nanoparticles based on phenylboronic acid and <i>N</i>-vinylcaprolactam for insulin delivery
Poly N-vinylcaprolactam-co-acrylamidophenylboronic acid p(NVCL-co-AAPBA) was prepared from N-vinylcaprolactam (NVCL) and 3-acrylamidophenylboronic acid (AAPBA), using 2,2-azobisisobutyronitrile (AIBN) as initiator. The synthesis and structure of the polymer were examined by Fourier Transform infrared spectroscopy (FT-IR) and 1H-NMR. Dynamic light scattering (DLS), lower critical solution temperature (LCST) and transmission electron microscopy (TEM) were utilized to characterize the nanoparticles, CD spectroscopy was used to determine if there were any changes to the conformation of the insulin, and cell and animal toxicity were also investigated. The prepared nanoparticles were found to be monodisperse submicron particles and were glucose- and temperature-sensitive. In addition, the nanoparticles have good insulin-loading characteristics, do not affect the conformation of the insulin and show low-toxicity to cells and animals. These p(NVCL-co-AAPBA) nanoparticles may have some value for insulin or other hypoglycemic protein delivery
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