EXPERIMENTAL AND MODELING STUDIES ON THE FORMULATION OF STABLE LIPID NANOPARTICLE DISPERSIONS

This thesis presents both experimental and modeling studies on the formulation of stable lipid nanoparticle dispersions. A population balance equation (PBE) model was developed for prediction of the average polymorph content and aggregate size distribution to better understand the undesirable SLN aggregation behavior. Experimental and modeling studies showed that the polymorphic transformation was the rate determining step for my system, SLNs with smaller initial size distributions aggregated more rapidly, and aggregates contained particles with both alpha and beta crystals. Next the effect of different liquid carrier oils on the crystallization and aggregation behavior of tristearin NLC dispersions was investigated. I found that NLC dispersion stability was strongly affected by the type and amount of the oil. The results suggested that oil trapped within the growing crystal matrix accelerated the polymorphic transformation but retarded the large shape change normally associated with the transformation. Based on PBE simulation results, I hypothesized that improved NLC dispersion stability was attributable to both reduced particle shape change, which created less new surface area to be covered by surfactant, and increased mobility of surfactant molecules, which resulted in available surfactant being more efficient at covering created surface area. Finally I also studied the effect of formulation variables on the aggregation behavior and rheology of NLC dispersions. I found that NLC dispersion viscosity was strongly affected by particle aggregation. The viscosity of the dispersion could be modified by at least an order of magnitude by controlling particle aggregation using different surfactant and oil concentrations. Oscillatory sweep tests showed typical behaviors of a viscoelastic liquid and a viscoelastic solid for non-aggregated and aggregated NLC dispersions, respectively. Modeling results suggested a stronger bonding force and a higher aggregation efficiency with decreasing surfactant and/or oil concentrations. Both oscillatory sweep experiments and modeling results indicated an interconnected network structure in the aggregated dispersions, while no indication of network formation was observed for non-aggregated dispersions. These results suggested that controlled aggregation represents a promising approach for modifying the viscosity of NLC dispersions without adding viscosity enhancers and could reduce the time and cost for NLC production

Morphological analysis: to evaluate the pattern of Residential building based on wind performance

[EN] Residential morphological patterns are reflection of people's living habits and tradition, local climate and building regulations, so that one of those factors could be studied through in order to understand residential morphological patterns. Based upon our previous study, we do know that in China living habits and local climate mainly influence the shape of residential buildings and apartment patterns, but we do not know whether the pattern of residential plots determined by FAR and sunshine hours are suitable for wind environment related to residential environmental quality. Therefore, it is very significant to evaluate wind environment within residential plots based on the apartment pattern controlled by various building codes. Our study focuses on the pattern of Slab apartments in Nanjing, which are mainly used in China, and selects 40 residential slices with different plot shapes, plot FAR, building heights and sizes. Based upon MATLAB, we have got all geometrical data between buildings among these slices to identify the spatial pattern character of each residential plot. Through evaluating wind environment of these slices by simulation we can obtain wind speed, pressure and age of air and choose the pattern of age of air as the main evaluation factor of wind performance. Correlation analysis will be made between the apartment patterns and pattern of age of air, by doing so, each typical space between buildings will be evaluated. Our study will reveal the relevance of apartment pattern and wind environment, which can be used to support and improve design in the future.Yang, Y.; You, W.; Peng, Y.; Ding, W. (2018). Morphological analysis: to evaluate the pattern of Residential building based on wind performance. En 24th ISUF International Conference. Book of Papers. Editorial Universitat Politècnica de València. 1461-1469. https://doi.org/10.4995/ISUF2017.2017.5977OCS1461146

Trifluorobenzamidine prevents allergic rhinitis by regulating IgE, IL-4 and IL-5 in T-cells

Purpose: To investigate the effect of trifluorobenzamidine (TBI) on a mouse model of ovalbumin (OVA)- induced allergic rhinitis. Methods: Allergic rhinitis was established in mice via sensitization on days 1, 5 and 14 through intraperitoneal injection of OVA (100 μg) in PBS. On day 15, the mice were subjected to intranasal exposure to OVA (1.5 mg dissolved in PBS). Prior to 10 days of intranasal exposure to OVA, the micewere treated with TBI at doses of 5, 10 and 20 μg/kg. Cytokine levels were determined using enzymelinked immunosorbent assay (ELISA) kits, while cyclooxygenase (COX)-2 and caspase-1 activity were assayed with western blotting. Results: Treatment with TBI significantly (p < 0.05) reduced OVA-mediated increases in nasal rub scores, and decreased serum levels of IgE, TNF-α, thymic stromal lymphopoietin (TSLP), IL-1β and histamine in mice. It also significantly regulated spleen weight and IL-4 secretion (p < 0.05) in OVAadministered mice. TBI significantly downregulated the expressions of IL-5, IL-13, TNFα, TSLP, IL-1β and IL-6 (p < 0.05). Administration of TBI caused a marked reduction in OVA-mediated increase in caspase-1 activity in mice intranasal tissues, and also significantly reduced OVA-induced excessive production of MIP-2 and ICAM-1 (p < 0.05). Moreover, TBI prevented OVA-induced infiltration of eosinophils and mast cells into intranasal tissues (p < 0.05). Conclusion: TBI reduces levels of IgE and various pro-inflammatory cytokines in OVA-administered mice. It also regulates Th1:Th2 ratio, inhibited activity of caspase-1, suppressed mast cell/eosinophil infiltration and reduced ICAM-1 and MIP-2 levels. Therefore, TBI possesses inhibitory potential against rhinitis allergy, and thus can potentially be developed as a new treatment strategy for asthma. Keywords: Trifluorobenzamidine, Anti-inflammation, Allergic rhinitis, Cytokines, Caspase-1, Itchin

A Machine Vision Method for Correction of Eccentric Error: Based on Adaptive Enhancement Algorithm

In the procedure of surface defects detection for large-aperture aspherical optical elements, it is of vital significance to adjust the optical axis of the element to be coaxial with the mechanical spin axis accurately. Therefore, a machine vision method for eccentric error correction is proposed in this paper. Focusing on the severe defocus blur of reference crosshair image caused by the imaging characteristic of the aspherical optical element, which may lead to the failure of correction, an Adaptive Enhancement Algorithm (AEA) is proposed to strengthen the crosshair image. AEA is consisted of existed Guided Filter Dark Channel Dehazing Algorithm (GFA) and proposed lightweight Multi-scale Densely Connected Network (MDC-Net). The enhancement effect of GFA is excellent but time-consuming, and the enhancement effect of MDC-Net is slightly inferior but strongly real-time. As AEA will be executed dozens of times during each correction procedure, its real-time performance is very important. Therefore, by setting the empirical threshold of definition evaluation function SMD2, GFA and MDC-Net are respectively applied to highly and slightly blurred crosshair images so as to ensure the enhancement effect while saving as much time as possible. AEA has certain robustness in time-consuming performance, which takes an average time of 0.2721s and 0.0963s to execute GFA and MDC-Net separately on ten 200pixels 200pixels Region of Interest (ROI) images with different degrees of blur. And the eccentricity error can be reduced to within 10um by our method

Bioactivity-guided fractionation of the triglyceride-lowering component and in vivo and in vitro evaluation of hypolipidemic effects of Calyx seu Fructus Physalis

<p>Abstract</p> <p>Background</p> <p>In folklore, some people take the decoction of <it>Calyx seu Fructus Physalis </it>(CSFP) for lowering blood lipids. The present study is designed to evaluate the lipid-lowering activities of CSFP, and search for its pharmacodynamical material.</p> <p>Methods</p> <p>CSFP was extracted by water and 75% ethanol, respectively. The extracts of CSFP for reducing serum lipid levels were evaluated on mouse model of hyperlipidemia. The optimized extract was subjected to the bioactivity-guided fractionation in which the liquid-liquid extraction, collumn chromatography, the <it>in vivo </it>and <it>in vitro </it>models of hyperlipidemia were utilized. The structure of active component was determined by ¹³C-NMR and ¹H-NMR.</p> <p>Results</p> <p>The 75% ethanol extract of CSFP decreased the serum total cholesterol (TC) and triglyceride (TG) levels in mouse model of hyperlipidemia. Followed a separation process for the 75% ethanol extract of CSFP, the fraction B was proved to be an active fraction for lowering lipid <it>in vivo </it>and <it>in vitro </it>experiments, which could significantly decrease the serum TC and TG levels in mouse model of hyperlipidemia, and remarkably decrease the increase of TG in primary mouse hepatocytes induced by high glucose and the increase of TG in HepG2 cells induced by oleic acid. The fraction B2, isolated from B on bioactivity-guided fractionation, could significantly decrease TG level in HepG2 cells. One compound with the highest content in B2 was isolated and determined as luteolin-7-O-beta-D-glucopyranoside by NMR spectra. It could significantly reduce the TG level in HepG2 cells, and inhibited the accumulation of lipids by oil red O stain.</p> <p>Conclusion</p> <p>Our results demonstrated that the 75% ethanol extract of CSFP could improve <it>in vitro </it>and <it>in vivo </it>lipid accumulation. Luteolin-7-O-beta-D-glucopyranoside might be a leading pharmacodynamical material of CSFP for lowering lipids.</p

Dynamic Brazilian Tests of Granite Under Coupled Static and Dynamic Loads

Rocks in underground projects at great depth, which are under high static stresses, may be subjected to dynamic disturbance at the same time. In our previous work (Li et al. Int J Rock Mech Min Sci 45(5):739–748, 2008), the dynamic compressive behaviour of pre-stressed rocks was investigated using coupled-load equipment. The current work is devoted to the investigation of the dynamic tensile behaviour of granite rocks under coupled loads using the Brazilian disc (BD) method with the aid of a high-speed camera. Through wave analyses, stress measurements and crack photography, the fundamental problems of BD tests, such as stress equilibrium and crack initiation, were investigated by the consideration of different loading stresses with abruptly or slowly rising stress waves. The specially shaped striker method was used for the coupled-load test; this generates a slowly rising stress wave, which allows gradual stress accumulation in the specimen, whilst maintaining the load at both ends of the specimen in an equilibrium state. The test results showed that the tensile strength of the granite under coupled loads decreases with increases in the static pre-stresses, which might lead to modifications of the blasting design or support design in deep underground projects. Furthermore, the failure patterns of specimens under coupled loads have been investigated