Applications of polymeric adjuvants in studying autoimmune responses and vaccination against infectious diseases

Polymers as an adjuvant are capable of enhancing the vaccine potential against various infectious diseases and also are being used to study the actual autoimmune responses using self-antigen(s) without involving any major immune deviation. Several natural polysaccharides and their derivatives originating from microbes and plants have been tested for their adjuvant potential. Similarly, numerous synthetic polymers including polyelectrolytes, polyesters, polyanhydrides, non-ionic block copolymers and external stimuli responsive polymers have demonstrated adjuvant capacity using different antigens. Adjuvant potential of these polymers mainly depends on their solubility, molecular weight, degree of branching and the conformation of polymeric backbone. These polymers have the ability not only to activate humoral but also cellular immune responses in the host. The depot effect, which involves slow release of antigen over a long duration of time, using different forms (particulate, solution and gel) of polymers, and enhances the co-stimulatory signals for optimal immune activation, is the underlying principle of their adjuvant properties. Possibly, polymers may also interact and activate various toll-like receptors and inflammasomes, thus involving several innate immune system players in the ensuing immune response. Biocompatibility, biodegradability, easy production and purification, and non-toxic properties of most of the polymers make them attractive candidates for substituting conventional adjuvants that have undesirable effects in the host.     

Low Velocity Impact and Mechanical Behaviour of Shot Blasted SiC Wire-Mesh and Silane-Treated Aloevera/Hemp/Flax-Reinforced SiC Whisker Modified Epoxy Resin Composites

Silicon - In this research the effect of adding silicon carbide nano whiskers (SiCw) into epoxy resin and the impact of reinforcing surface treated SiC wire-mesh (SiCwm) and woven...     

Multivariant approach to optimize biodiesel extraction from neem oil using two-stage esterification process and its quality assessment

Finding new biofuel resources and consolidating the preliminary findings on biodiesel extraction are important to optimize mass production. In this paper biodiesel is extracted from non-edible, abundantly available, potential, and viable neem oil. Design of Experiment is employed to optimize the process parameters of the two-stage esterification process. Methanol has the greatest influence in both stages, followed by choice of catalyst and duration. Standard test procedures were followed to ensure the adequacy of the fuel properties, and the results are encouraging in regard to using neem oil as a potentially renewable and sustainable biodiesel source.     

A rule-based method for scalable and traceable evaluation of system architectures

Despite the development of a variety of decision-aid tools for assessing the value of a conceptual design, humans continue to play a dominant role in this process. Researchers have identified two major challenges to automation, namely the subjectivity of value and the existence of multiple and conflicting customer needs. A third challenge is however arising as the amount of data (e.g., expert judgment, requirements, and engineering models) required to assess value increases. This brings two challenges. First, it becomes harder to modify existing knowledge or add new knowledge into the knowledge base. Second, it becomes harder to trace the results provided by the tool back to the design variables and model parameters. Current tools lack the scalability and traceability required to tackle these knowledge-intensive design evaluation problems. This work proposes a traceable and scalable rule-based architecture evaluation tool called VASSAR that is especially tailored to tackle knowledge-intensive problems that can be formulated as configuration design problems, which is demonstrated using the conceptual design task for a laptop. The methodology has three main steps. First, facts containing the capabilities and performance of different architectures are computed using rules containing physical and logical models. Second, capabilities are compared with requirements to assess satisfaction of each requirement. Third, requirement satisfaction is aggregated to yield a manageable number of metrics. An explanation facility keeps track of the value chain all along this process. This paper describes the methodology in detail and discusses in particular different implementations of preference functions as logical rules. A full-scale example around the design of Earth observing satellites is presented.     

Incidence of AZF (azoospermia factor) deletions and familial forms of infertility among patients requiring intracytoplasmic spermatozoa injection (ICSI)

PURPOSE: The aim of our study was to determine the incidence of AZF deletions and familial forms of infertility suggesting autosomal mutations among patients requiring intracytoplasmic sperm injection with ejaculated sperm. METHODS: Cases with obstructive pathologies were excluded; 81 patients were classified according to the numeration of spermatozoa. The distribution was as follows: 10 cases with normal numeration (greater than 20 million/ml) (group 1), 10 cases with between 10 and 20 million/ml (group 2), 6 cases with between 5 and 10 million/ml (group 3), 15 cases with between 1 and 5 million/ml (group 4), 29 cases with less than 1 million/ml (group 5), and 11 azoospermic patients (group 6). The infertility of 11 of the 81 patients might be explained by testicular ectopy. RESULTS: We found two deletions limited to the AZFc region among our 81 infertile patients--one deletion in group 5 and one deletion in group 4 (both groups of oligozoospermic patients)--and no deletion in the groups with normal or subnormal numerations. We found six familial forms of infertility. We did not find any AZF deletion, neither in these 6 patients nor in the 11 with testicular ectopy. The identification of these families of infertile men will allow research of autosomal genes involved in male infertilities. CONCLUSIONS: It is important to test deletions of the AZFc region for oligozoospermic patients, and familial forms of infertility do not seem to concern the same individuals.     

Sterol composition of Bulgarian soya and corn oils

The free sterols, the sterol esters and the sterol glycosides of the raw soya and corn oils as well as those of the technical lecithin and the deodorizer distillated of the latter oils were isolated by preparative TLC. The composition of each of the isolated sterol derivatives was determined by GLC and MS. Sitosterol, campesterol, stigmasterol and an unknown sterol with a molecular weight of 428 are contained in almost all of the examined fractions of the soya oil and its refinement byproducts. Dehydrocampesterol is present in the free sterols of the raw soya oil and the soya lecithin. Stigmasterol is contained in the soya deodorizer distillate in high amounts. It was established that cholesterol was present in the sterol esters of the raw soya oil high amounts. Delta7-stigmastenol occurs only in the sterol esters of the latter oil. Sitosterol, campesterol and stimgasterol are the main components of all sterol fractions of the corn oil and its refinement products. Dehydrocampesterol and unknown sterols with molecular weights of 428 are present in the free sterols of the raw corn oil. Some sterol glycosides of the soya and corn lecithin are esterified with the same major fatty acid components of the glycerides, palmitic acid being the main one. The fatty acid compositon of sterol esters of the raw soya and corn oil roughly corresponds to the fatty acid composition of oils.     

Attenuation statistics estimated from radar measurements in MEO satellite communication systems for mobile terminals

Based on experimental data, we have reported a method to scale the cumulative time, T_F,T(A), a given attenuation, A (dB), is exceeded in a MEO satellite system in fixed terminals, to the time, T_M,T(A), A is exceeded in mobile terminals. Zigzag routes and ring roads simulated city patterns; straight routes simulated freeways. In all cases, T_M,T(A) can be expressed as T_M,T(A)=ξT_F,T(A) with a probability scaling factor ξ independent of A. Although the satellite systems have been simulated at 19.77 GHz, the results concerning ξ can be considered frequency‐independent. We have used a very large number of rain‐rate maps of storms randomly observed in 1991–1992 by a meteorological radar in Northern Italy. The speed of vehicles was modelled as a lognormal random variable. We found: (a) in zigzag routes T_M,T(A)<T_F,T(A), i.e. ξ<1, with results depending on vehicle speed modelling and starting conditions; (b) in ring roads there is no difference between fixed and mobile systems (ξ≈1); (c) in straight freeways T_M,T(A)?T_F,T(A) (ξ?1) and T_M,T(A) can change significantly in different straight lines and in opposite directions (anisotropy and asymmetry) for medium–large attenuation. When compared with zigzag routes or ring roads, the performance in straight freeways is the most optimistic. The numerical values of ξ applicable to a MEO satellite system are not significantly different from those applicable to a GEO satellite system working in the same conditions. Copyright © 2002 John Wiley & Sons, Ltd.     

Classification of Almond Cultivars Using Oil Volatile Compound Determination by HS-SPME–GC–MS

Protected designations of origin “Alicante” and “Jijona” nougats are manufactured products produced using raw materials from Eastern Spain. In order to avoid adulteration practices, determination of volatile compounds from three different almond cultivars (Spanish Guara and Marcona and, from the USA, Butte) was performed to obtain a set of parameters for discrimination between Spanish and American cultivars. Factorial experimental design was applied for the development of a headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME–GC–MS) analytical method for isolation and determination of the volatile compounds in almond oils. Main HS-SPME variables optimized were extraction temperature, extraction time, and stirring speed. Several volatile compounds including aldehydes, alkanes, alcohols and aromatic hydrocarbons were identified. Multivariate techniques were applied for classification and discrimination of the different almond cultivars studied. Specifically, cluster and stepwise linear discriminant analysis (LDA) were used, with LDA showing the best performance. The results obtained demonstrated that the proposed method combined with multivariate statistical analysis can be successfully applied for discrimination among different almond cultivars.     

Characterization of Almond Cultivars by the Use of Thermal Analysis Techniques. Application to Cultivar Authenticity

Almonds are subjected to thermal processes in the production of processed food and this can affect their thermal stability and lead to oxidation processes. In this work, almond samples from three different cultivars (Spanish Guara and Marcona, and American Butte) were characterized by using Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) at different heating rates. Crystallization and melting parameters were determined by DSC; whereas thermal stability was studied by TGA, showing no apparent degradation for all samples up to around 290 °C. Butte samples showed the lowest DSC values and TGA initial degradation temperature. These results were linked with differences in fatty acid profiles between Butte and Spanish almond cultivars, Butte presenting higher linoleic acid content. Successful discrimination was obtained for samples analyzed at 2 and 10 °C min⁻¹ heating rates for DSC and TGA, respectively, by applying multivariate stepwise linear discriminant analysis (LDA). The results obtained proved the suitability of thermal analysis techniques combined with LDA for an easy and fast discrimination among different almond cultivars to control eventual adulteration in food processing.