Protection of biodiesel based on sunflower oil from oxidative degradation by natural antioxidants

Biodiesel as an alternative diesel fuel obtained by transesterification of vegetable fats and oils, using alcohol in the presence of a catalyst, has some advantages such as reduced emissions of unburned hydrocarbons, carbon monoxide, sulfates, polycyclic aromatic hydrocarbons, and particular matter but its drawback, of being more prone to oxidation than petroleum-based diesel fuel, can cause the fuel to become acidic (cause fuel system corrosion) and to form insoluble gums and sediments and consequently increase its viscosity. In this study, in order to increase the stability of biodiesel based on high oleic acid sunflower oil against oxidation process during the storage and distribution, different percents S0.01%, 0.02%, 0.05%, 0.1%, and 0.2% (w/v)C of maize flour contaminated by mycotoxins, thus useless for human consumption, were added as natural antioxidants. The antioxidant effect increased with concentration up to an optimal level. Above the optimal level the increase in antioxidant effect with its concentration was relatively small. Oxidative stability of biodiesel was determined using two parallel methods, the Schaal oven storage test (at 70°C) and the Rancimat method (at 110°C). The induction times obtained by the Rancimat method were more similar to the values determined by the oven test. The highest protective effect was observed in samples containing 0.1% (w/ v) of added antioxidants

Long COVID following mild SARS-CoV-2 infection: characteristic T cell alterations and response to antihistamines

Long COVID is characterized by the emergence of multiple debilitating symptoms following SARS-CoV-2 infection. Its etiology is unclear and it often follows a mild acute illness. Anecdotal reports of gradual clinical responses to histamine receptor antagonists (HRAs) suggest a histamine-dependent mechanism that is distinct from anaphylaxis, possibly mediated by T cells, which are also regulated by histamine. T cell perturbations have been previously reported in post-viral syndromes, but the T cell landscape in patients who have recovered from mild COVID-19 and its relationship to both long COVID symptoms and any symptomatic response to HRA remain underexplored. We addressed these questions in an observational study of 65 individuals who had recovered from mild COVID-19. Participants were surveyed between 87 and 408 days after the onset of acute symptoms; none had required hospitalization, 16 had recovered uneventfully, and 49 had developed long COVID. Symptoms were quantified using a structured questionnaire and T cell subsets enumerated in a standard diagnostic assay. Patients with long-COVID had reduced CD4+ and CD8+ effector memory (EM) cell numbers and increased PD-1 (programmed cell death protein 1) expression on central memory (CM) cells, whereas the asymptomatic participants had reduced CD8+ EM cells only and increased CD28 expression on CM cells. 72% of patients with long COVID who received HRA reported clinical improvement, although T cell profiling did not clearly distinguish those who responded to HRA. This study demonstrates that T cell perturbations persist for several months after mild COVID-19 and are associated with long COVID symptoms

Multi-stage calibration of the simulation model of a school building through short-term monitoring

The increasing attention on the improvement of new and existing buildings' performance is emphasizing the importance of the reliability of the simulation models in predicting the complexity of the building behaviour and, consequently, in some advanced applications of building simulation, such as the optimization of the choice of different Energy Efficiency Measures (EEMs) or the adoption of model predictive control strategies. The reliability of the energy model does not depend only on the quality and details of the model itself, but also on the uncertainty related to many input values, such as the physical properties of materials and components, the information on the building management and occupation, and the boundary conditions considered for the simulation. Especially for the existing buildings, this kind of data is often missing or characterized by high uncertainty, and only very simplified behavioural models of occupancy are available. This could compromise the optimization process and undermine the potential of building simulation. In this context, the calibration of the simulation model by means of on-site monitoring is of crucial importance to increase the reliability of the predictions, and to take better decisions, even though this process can be time consuming. This work presents a multi-stage methodology to calibrate the building energy simulation by means of low-cost monitoring and short-term measurements. This approach is applied to a Primary School in the North-East of Italy, which has been monitored from December 2012 to April 2014. Four monitoring periods have been selected to calibrate different sets of variables at a time, while the validation has been carried out on two different periods. The results show that even if less than 8 weeks have been considered in the proposed calibration approach, the maximum error in the estimation of the temperature is less than ±0.5 in 77.3% of the timesteps in the validation period

1.19 Calcium Phosphate Ceramics With Inorganic Additives ☆

The use of inorganic compounds as synthetic growth factors is a promising approach for improving the biological properties of existing synthetic bone graft substitutes such as calcium phosphates. In this article we have described some of the inorganic additives that may improve the capabilities of calcium phosphates, and help bridge the gap toward autograft?s performance known as gold standard for bone regeneration. This article focuses on the specific roles of bioinorganics in processes related to bone formation and resorption and how these modify the biological properties of calcium phosphates, and finally provides insight into the future of this field

Half-Seed Analysis for Comparing Linolenic Acid Synthesis Between High and Low Oleic Acid Sunflower Inbred Lines

The modification of fatty acid composition of two sunflowers inbred lines, HA89 and R978, low oleic acid (normal) and high oleic acid (mutant) respectively, in seeds and during the first stages of growth (A1-B2) was studied under controlled conditions. Enzymatic mechanisms have great effect on the catabolism of seed stored lipids. Temperature and oxygen regulation influence developing sunflower seeds. For simultaneous study of seed and developing seed, half-seed analysis technique was used. The behavior of the fatty acids during the germination in cotyledon of seed showed the increase of linolenic acid in both lines, demonstrating the activity of linoleic acid desaturase (\uc46-desaturase). But linoleic acid as a substrate for linoleate desaturase increased during all stages of developing only in mutant line that revealed higher activity of oleic acid desaturase (\uc412-desaturase) in transforming oleic acid to linoleic acid in this line, and lower activity of this enzyme in low oleic acid line, the reasons probably being the low availability of substrate of this enzyme in low oleic acid line and the complexity of enzymatic mechanisms. The modification of fatty acids in developing sunflower, depends not only on ambient conditions such as temperature and oxygen regulation as described by many authors, but also on the genotype. \ua9 2004, by Walter de Gruyter Berlin/Boston. All rights reserved

A multi-stages approach to the calibration of a school building's simulation model

The calibration process is an important step to improve the reliability of the simulation model and to reduce the differences between simulated and measured building energy performance. This paper presents a methodology to calibrate a building simulation model by means of low-cost monitoring set-up and short term measurements. The proposed method can be defined as a multi-stage calibration. It is based on the assumption that input data affect the simulation results differently according to the considered period of the year. It seems thus possible to calibrate different sets of parameters in different reference periods, with the advantage of using shorter recording times when the calibration periods have been consistently selected

Double Circular-Triangular Six-Degrees-of-Freedom Parallel Robot

This paper describes a new structure of a six-DOF parallel robot. First, a known planar three-DOF double-triangular structure is modified by replacing the stationary triangle with a circle. It increases the work envelope considerably especially when rotational motions are required. The ability for unlimited rotational motion allows extending the structure into six-DOF by using two sets of stationary circles and moveable triangles. Each set can actuate the moving triangle in a planar three-DOF motion and hence actuate a line connecting the centers of the movable triangles in four-DOF. The robot's end-effector is attached to a link along this line while rotation about and translation along this line are obtained by the additional rotational DOF of the movable triangles. The solution of the direct kinematics of this six-DOF manipulator is given in a closed-form and it is shown that at most, four different solutions exist

Competition and Selection Among Conventions

In many domains, a latent competition among different conventions determines which one will come to dominate. One sees such effects in the success of community jargon, of competing frames in political rhetoric, or of terminology in technical contexts. These effects have become widespread in the online domain, where the data offers the potential to study competition among conventions at a fine-grained level. In analyzing the dynamics of conventions over time, however, even with detailed on-line data, one encounters two significant challenges. First, as conventions evolve, the underlying substance of their meaning tends to change as well; and such substantive changes confound investigations of social effects. Second, the selection of a convention takes place through the complex interactions of individuals within a community, and contention between the users of competing conventions plays a key role in the convention's evolution. Any analysis must take place in the presence of these two issues. In this work we study a setting in which we can cleanly track the competition among conventions. Our analysis is based on the spread of low-level authoring conventions in the eprint arXiv over 24 years: by tracking the spread of macros and other author-defined conventions, we are able to study conventions that vary even as the underlying meaning remains constant. We find that the interaction among co-authors over time plays a crucial role in the selection of them; the distinction between more and less experienced members of the community, and the distinction between conventions with visible versus invisible effects, are both central to the underlying processes. Through our analysis we make predictions at the population level about the ultimate success of different synonymous conventions over time--and at the individual level about the outcome of "fights" between people over convention choices.Comment: To appear in Proceedings of WWW 2017, data at https://github.com/CornellNLP/Macro