4,319 research outputs found

    Fabrication, Characterization and Biological Fate of Phytochemical Delivery System

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    Polymethoxyflvones (PMFs) are a group compounds with promising cancer preventing activities and many other health benefits. There\u27s a growing interest in fabricating delivery systems for PMFs as well as other phytochemicals due to their low water solubility. Firstly, we use nanoemulsion delivery system to encapsulate Ī²-carotene. Sonication assisted method was developed to dissolve Ī²-carotene to ensure minimum degradation. Powdered nanoemulsion was obtained after spray dry and freeze dry. Sample obtained after freeze dry showed better physiochemical characteristics. Then we use protein nanoparticle delivery system to encapsulate PMFS. The nanoparticle delivery system was fabricated by mixing the aqueous phase containing Ī²-lactoglobulin with organic phase containing ethanol and tangeretin. Powder was obtained after vacuum evaporation of ethanol followed by freeze-drying. This powder can be easily dispersed into water and have similar property as freshly prepared, suggesting excellent applicability of the system as a convenient powder ingredient. Different delivery systems were made by mixing this powder with stock emulsion to represent various types of diets. These systems were then go through in vitro digestion process. The delivery system contained 4% oil exhibited the highest bioaccessibility of tangeretin due to increased amount of mixed micelle formed after digestion in simulated small intestine. The following permeability determination experiments on Caco-2 cell monolayer model suggested digested sample with higher oil content has higher permeability than PMF that did not go through the digestion process. In order to further study the uptake and internalization of PMFs, a new approach to visualize polymethoxyflavones (PMFs) inside the cell and in mice colon using a fluorescence microscope was developed. 5, 3\u27, 4\u27-tridemethylnobiletin (THN) was used for further study due to strong fluorescent intensity upon conjugation with DPBA. Fluorescence spectroscopy indicated this conjugate has the maximum excitation wavelength of 490 nm and maximum emission wavelength of 570 nm. Both mass spectroscopy and Raman spectroscopy confirmed the reaction between one or two hydroxyl group on THN and diphenyl boron group on DPBA. This method could easily detect the PMFs in the single suspend cell or in the attached cell. It can also be used to visualize PMFs absorbed by mouse tissue such as colon

    Generalized nowhere zero flow

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    Let G be an undirected graph, A be an (additive) abelian group and A* = A - {lcub}0{rcub}. A graph G is A-connected if G has an orientation D(G) such that for every function b : V(G ) A satisfying SvāˆˆVG b(v) = 0, there is a function f : E(G) A* such that at each vertex v āˆˆ V(G), āˆ‚f(v), the net flow out from v, equals b( v). An A-nowhere-zero-flow (abbreviated as A-NZF) in G is a function f : E(G) A* such that at each vertex v āˆˆ V(G), āˆ‚f(v) = 0.;In this paper, we investigate the group connectivity number Lambda g(G) = min{lcub}n : if A is an abelian group with |A| ā‰„ n, then G is A-connected{rcub} for certain families of graphs including complete bipartite graphs, chordal graphs, wheels and biwheels. We also give some general results and methods to approach nowhere zero flow and group connectivity problems

    Analysis of National Patent Cooperation between Jiangsu Province and the Belt and Road Initiative

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    With the further advancement of the ā€œOne Belt, One Roadā€ strategy, patent cooperation between Jiangsu Province and countries along the route has been further strengthened. At the US Patent and Trademark Office (USTPO) and the Jiangsu Provincial Productivity Promotion Center, we searched for cooperation patents and technology alliances between China and 65 countries along the Belt and Road Initiative, and analyzed the current situation of time series distribution, spatial distribution, and main technical fields. The results show that: ā‘ Science and technology cooperation generally maintains a growth trend, which can be divided into three stages: start-up period, volatility growth period and rapid growth period; ā‘”the cooperation area presents an unbalanced feature, and the cooperation patents of the top five countries account for 85.06% of the total. ā‘¢The technical fields and directions of cooperation are more focused, and the cooperation patents are concentrated in the fields of electricity, human life, and physics. ā‘£ Technology transfer and paper cooperation are mainly distributed in West Asia, South Asia, CIS, Eastern Europe, Central and Eastern Europe, and lack of innovative cooperation with East Asia and Central Asia. The conclusions of the study can provide reference for further scientific cooperation and policy formulation in the future

    A Bayesian Approach to the Understanding of Exoplanet Populations and the Origin of Life

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    The study of extrasolar planets, or exoplanets for short, has developed rapidly over the last decade. While we have spent much effort building both ground-based and space telescopes to search for exoplanets, it is even more important that we use the observational data wisely to understand them. Exoplanets are of great interest to both astronomers and the general public because they have shown varieties of characteristics that we couldn't have anticipated from planets within our Solar System. To properly analyze the exoplanet populations, we need the tools of statistics. Therefore, in Chapter 1, I describe the science background as well as the statistical methods which will be applied in this thesis. In Chapter 2, I discuss how to train a hierarchical Bayesian model in detail to fit the relationship between masses and radii of exoplanets and categorize exoplanets based on that. A natural application that comes with the model is to use it for future observations of mass/radius and predict the other measurement. Thus I will show two application cases in Chapter 3. Composition of an exoplanet is also very much constrained by its mass and radius. I will show an easy way to constrain the composition of exoplanets in Chapter 4 and discuss how more complicated methods can be applied in future works. Of even greater interest is whether there is life elsewhere in the Universe. Although the future discovery of extraterrestrial life might be totally a fluke, a clear sketched plan always gives us some directions. Research in this area is still very preliminary. Fortunately, besides directly searching for extraterrestrial life, we can also apply statistical reasoning to first estimate the rate of abiogenesis, which will give us some clue on the question of whether there is extraterrestrial life in a probabilistic way. In Chapter 5, I will discuss how different methods can constrain the abiogenesis rate in an informatics perspective. Finally I will give a brief summary in Chapter 6
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