Encapsulation of diclofenac molecules into poly (ε caprolactone) electrospun fibers for delivery protection

Mg-Al Hydrotalcite-like clay (LDH) intercalated with diclofenac anions (HTlc-DIC) was introduced into poly(-caprolactone) (PCL) in different concentrations by the electrospinning technique, and mats of nonwoven fibers were obtained and compared to the pristine pure electrospun PCL. The fibers, characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, show an exfoliated clay structure up to 3 wt%, a good thermal stability of the diclofenac molecules and a crystallinity of PCL comparable to the pure polymer. The scanning electron microscopy revealed electrospun PCL and PCL composite fibers diameters ranging between 500 nm to 3.0 m and a generally uniform thickness along the fibers. As the results suggested the in vitro drug release from the composite fibers is remarkably slower than the release from the corresponding control spun solutions of PCL and diclofenac sodium salt. Thus, HTlc-DIC/PCL fibrous membranes can be used as an antinflammatory scaffold for tissue engineering

Structural classification by the Lipase Engineering Database: a case study of Candida antarctica lipase A

<p>Abstract</p> <p>Background</p> <p>The Lipase Engineering Database (LED) integrates information on sequence, structure and function of lipases, esterases and related proteins with the α/β hydrolase fold. A new superfamily for <it>Candida antarctica </it>lipase A (CALA) was introduced including the recently published crystal structure of CALA. Since CALA has a highly divergent sequence in comparison to other α/β hydrolases, the Lipase Engineering Database was used to classify CALA in the frame of the already established classification system. This involved the comparison of CALA to similar structures as well as sequence-based comparisons against the content of the LED.</p> <p>Results</p> <p>The new release 3.0 (December 2009) of the Lipase Engineering Database contains 24783 sequence entries for 18585 proteins as well as 656 experimentally determined protein structures, including the structure of CALA. In comparison to the previous release <abbrgrp><abbr bid="B1">1</abbr></abbrgrp> with 4322 protein and 167 structure entries this update represents a significant increase in data volume. By comparing CALA to representative structures from all superfamilies, a structure from the deacetylase superfamily was found to be most similar to the structure of CALA. While the α/β hydrolase fold is conserved in both proteins, the major difference is found in the cap region. Sequence alignments between both proteins show a sequence similarity of only 15%. A multisequence alignment of both protein families was used to create hidden Markov models for the cap region of CALA and showed that the cap region of CALA is unique among all other proteins of the α/β hydrolase fold. By specifically comparing the substrate binding pocket of CALA to other binding pockets of α/β hydrolases, the binding pocket of <it>Candida rugosa </it>lipase was identified as being highly similar. This similarity also applied to the lid of <it>Candida rugosa </it>lipase in comparison to the potential lid of CALA.</p> <p>Conclusion</p> <p>The LED serves as a valuable tool for the systematic analysis of single proteins or protein families. The updated release 3.0 was used for the evaluation of α/β hydrolases. The HTML version of the database with new features is available at <url>http://www.led.uni-stuttgart.de</url> and provides sequences, structures and a set of analysis tools including phylogenetic trees and HMM profiles</p

Use of Taguchi Design of Experiments to Determine ALPLS Ascent Delta-5 Sensitivities and Total Mass Sensitivities to Release Conditions and Vehicle Parameters

The objective of this study is to evaluate the use of Taguchi's Design of Experiment Methods to improve the effectiveness of this and future parametric studies. Taguchi Methods will be applied in addition to the typical approach to provide a mechanism for comparing the results and the cost or effort necessary to complete the studies. It is anticipated that results of this study should include an improved systematic analysis process, an increase in information obtained at a lower cost, and a more robust, cost effective vehicle design

Some issues in the 'archaeology' of software evolution

During a software project's lifetime, the software goes through many changes, as components are added, removed and modified to fix bugs and add new features. This paper is intended as a lightweight introduction to some of the issues arising from an `archaeological' investigation of software evolution. We use our own work to look at some of the challenges faced, techniques used, findings obtained, and lessons learnt when measuring and visualising the historical changes that happen during the evolution of software

An experimental study of the dual-fuel performance of a small compression ignition diesel engine operating with three gaseous fuels

A dual-fuel engine is a compression ignition (CI) engine where the primary gaseous fuel source is premixed with air as it enters the combustion chamber. This homogenous mixture is ignited by a small quantity of diesel, the ‘pilot’, that is injected towards the end of the compression stroke. In the present study, a direct-injection CI engine, was fuelled with three different gaseous fuels: methane, propane, and butane. The engine performance at various gaseous concentrations was recorded at 1500 r/min and quarter, half, and three-quarters relative to full a load of 18.7 kW. In order to investigate the combustion performance, a novel three-zone heat release rate analysis was applied to the data. The resulting heat release rate data are used to aid understanding of the performance characteristics of the engine in dual-fuel mode. Data are presented for the heat release rates, effects of engine load and speed, brake specific energy consumption of the engine, and combustion phasing of the three different primary gaseous fuels. Methane permitted the maximum energy substitution, relative to diesel, and yielded the most significant reductions in CO2. However, propane also had significant reductions in CO2 but had an increased diffusional combustion stage which may lend itself to the modern high-speed direct-injection engine

Assessing architectural evolution: A case study

This is the post-print version of the Article. The official published can be accessed from the link below - Copyright @ 2011 SpringerThis paper proposes to use a historical perspective on generic laws, principles, and guidelines, like Lehman’s software evolution laws and Martin’s design principles, in order to achieve a multi-faceted process and structural assessment of a system’s architectural evolution. We present a simple structural model with associated historical metrics and visualizations that could form part of an architect’s dashboard. We perform such an assessment for the Eclipse SDK, as a case study of a large, complex, and long-lived system for which sustained effective architectural evolution is paramount. The twofold aim of checking generic principles on a well-know system is, on the one hand, to see whether there are certain lessons that could be learned for best practice of architectural evolution, and on the other hand to get more insights about the applicability of such principles. We find that while the Eclipse SDK does follow several of the laws and principles, there are some deviations, and we discuss areas of architectural improvement and limitations of the assessment approach

Some issues in the 'archaeology' of software evolution

During a software project's lifetime, the software goes through many changes, as components are added, removed and modified to fix bugs and add new features. This paper is intended as a lightweight introduction to some of the issues arising from an `archaeological' investigation of software evolution. We use our own work to look at some of the challenges faced, techniques used, findings obtained, and lessons learnt when measuring and visualising the historical changes that happen during the evolution of software

Report from GI-Dagstuhl Seminar 16394: Software Performance Engineering in the DevOps World

This report documents the program and the outcomes of GI-Dagstuhl Seminar 16394 "Software Performance Engineering in the DevOps World". The seminar addressed the problem of performance-aware DevOps. Both, DevOps and performance engineering have been growing trends over the past one to two years, in no small part due to the rise in importance of identifying performance anomalies in the operations (Ops) of cloud and big data systems and feeding these back to the development (Dev). However, so far, the research community has treated software engineering, performance engineering, and cloud computing mostly as individual research areas. We aimed to identify cross-community collaboration, and to set the path for long-lasting collaborations towards performance-aware DevOps. The main goal of the seminar was to bring together young researchers (PhD students in a later stage of their PhD, as well as PostDocs or Junior Professors) in the areas of (i) software engineering, (ii) performance engineering, and (iii) cloud computing and big data to present their current research projects, to exchange experience and expertise, to discuss research challenges, and to develop ideas for future collaborations

Development of pH-controlled triggering mechanisms for controlled release of lysozyme

Thesis(Master)--Izmir Institute of Technology, Food Engineering, Izmir, 2011Includes bibliographical references (leaves: 58-61)Text in English; Abstract: Turkish and Englishxi, 61 leavesIn this study, zein and whey protein (WP) based films and their blends and composites have been prepared to obtain pH-controlled triggering mechanisms for controlled release of lysozyme. The total amount of lysozyme released from standard zein films was not considerably affected from changes in pH between 7.3 and 5.3 since this hydrophobic biopolymer lacked charged ionisable groups to bind lysozyme ionically. In contrast, incorporation of lentil protein isolate (LPI) into zein created a composite structure and caused binding of positively charged lysozyme (pI>9.0) on negatively charged groups of LPI (pI: 4.5-6) within the film matrix in release medium with pH between 5.3 and 7.3. The amount of bound lysozyme in zein-LPI composites increased linearly as LPI concentration increased between 1,5 and 4,5 mg/cm2 at pH 7.3. The release of bound enzyme could be triggered by reducing pH of release medium from 7.3 to 4.3, down below pI of LPI. On the other hand, films of WP (pI≈5.2) bind considerable amount of lysozyme due to their inherent net negative charges close to neutrality. The release of bind lysozyme could be trigged as pH of release medium reduced from 6.0 to 3.0, down below the pI of WP. The preparation of WP-oleic acid blend and WP-bees wax composites increased the film porosity and amounts of released lysozyme from films at pH 4.5 and 5.0, by 2-4 and 1.2-1.5 folds, respectively. The zein and WP based films containing 0.7 to 1.4 mg/cm2 lysozyme showed good antimicrobial activity against Listeria innocua. This work showed the potential of creating pH-controlled release systems during antimicrobial packaging of food