Purification,structural data and biological properties of polysaccharide from Prunus amygdalus gum

This work demonstrates the efficiency of almond gum polysaccharides (AGPs) as bioactive compounds. AGPs were first extracted using H₂O₂, in the presence of NaOH, at different times and temperatures. The optimal extraction conditions were 4% H₂O₂ and 2 N NaOH, for 7 h at 50 °C, leading to an extraction yield of 58.2% (w/w). After a purification step, the retained AGPs were characterised using high‐performance liquid chromatography showing a molecular weight of 99.3 kDa. The monosaccharide composition of AGPs were assessed using gas chromatography–mass spectrometry. AGPs were found to be a complex heteropolysaccharide with a repeating unit mainly composed of galactose, arabinose, xylose, mannose, rhamnose, and glucuronic acid with the respective ratios: 45:26:7:10:1:11. The acidic nature of the polysaccharide is due to the presence of glucuronic acid. Total antioxidant activity, free radical‐scavenging activity and reducing power assay of AGPs were investigated. The obtained results showed high antioxidant activities of AGPs. Furthermore, beyond 60 mg mL^?1, AGPs exhibited bacterial growth inhibition for five pathogenic strains: Escherichia coli, Staphylococcus aureus, Enterococcus feacalis, Pseudomonas aeruginosa and Salmonella typhimurium.     

Interprocedural and Flow-Sensitive Type Analysis for Memory and Type Safety of C Code

The explicit memory management and type conversion endow the C language with flexibility and performance that render it the de facto language for system programming. However, these appealing features come at the cost of programs’ safety. Due to the C language permissiveness, highly skilled but inadvertent programmers often spawn insidious programming errors that yield exploitable code. In this paper, we present a novel type and effect analysis for detecting memory and type errors in C source code. We extend the standard C type system with effect, region, and host annotations that hold valuable safety information. We also define static safety checks to detect safety errors using the aforementioned annotations. Our analysis performs in an intraprocedural phase and an interprocedural phase. The flow-sensitive and alias-sensitive intraprocedural phase propagates type annotations and applies safety checks at each program point. The interprocedural phase generates and propagates unification constraints on type annotations across function boundaries. We present an inference algorithm that automatically infers type annotations and applies safety checks to programs without programmers’ interaction.     

Robustness design of a dynamic output-feedback decentralized controller using <Emphasis Type="Italic">H</Emphasis><Subscript>∞</Subscript> synthesis and LMI paradigm

This paper proposes developing a H _∞ dynamic output-feedback decentralized control design method for nonlinear interconnected systems subject to time-varying parameters and external disturbances. The designed controller is formulated as an optimization problem subject to linear matrix inequalities (LMIs) for the concurrent computation of the decentralized observation and control gains, and for the external disturbance mitigation by means of a H _∞ performance criterion minimization. The propounded optimization problem, designed in LMI conditions, is expeditiously resolved by a one-step procedure to override the conservatism generated by using many step-based procedures often used in the analysis and synthesis of interconnected systems. The effectiveness of the developed control scheme is demonstrated through simulation results of multimachine power systems.     

Long term ageing of polyamide 6 and polyamide 6 reinforced with 30% of glass fibers: physicochemical,mechanical and morphological characterization

Hygrothermal ageing of polyamide 6 (PA6) and polyamide 6 reinforced with 30 wt% of glass fibers (PA6GF30) was undertaken. Immersion was conducted in distilled water at 90 °C and 100% relative humidity (RH) for up to 80 days (1920 h). Results revealed a noteworthy decrease either in glass transition temperature T_g or in tensile properties, at early stage of ageing, for both studied materials. This decline was mainly caused by the plasticization effect of water and the weakness of the interfacial interactions leading as a consequence to a loss of adhesion between fiber and matrix. Afterwards, physical and mechanical properties decrease monotonically testifying the occurrence of exhaustive damages and chemical reaction phenomena. Such phenomena were yellowing and crazing formation which were observed for both materials after 1920 h of conditioning. The former is caused by the thermo- oxidation whereas the latter results from the release of internal stresses induced by water sorption. These chemical reactions were monitored by infrared spectroscopy. Thus, an increase of the free N-H stretch and the carbonyl groups (imides) was noted. Accordingly, it seems that long term immersion in distilled water at high temperature induces chemical reactions which indicate the severity of the damage.     

A new interval diagnosis method: Application to the spacecraft rendezvous phase of the Mars sample return mission

This paper presents a new optimized interval principal component analysis applied to detect and isolate actuators faults of an autonomous spacecraft involved in the rendezvous phase of the Mars sample return mission. Based on the exploitation of various arithmetic and interval analysis properties, the new interval model is built by solving the interval eigenpairs problem via a resolution of a parametric linear programming problem. The detection and isolation phases are performed by extending the classic methods to interval-valued data. The proposed method is applied to detect and isolate actuators faults that can occur on the spacecraft's thrusters. Based on data provided by a “high fidelity” industrial simulator developed by Thales Alenia Space, the obtained results proved the effectiveness of the proposed interval fault diagnosis method on detecting and isolating thrusters' faults.     

Unexploited Thapsia garganica,Orlaya maritima,and Retama raetam Seeds: Potential Sources of Unsaturated Fatty Acid and Natural Antioxidants

Total lipid contents, fatty acid compositions, phenolic profiles and antioxidants activities of seeds from Thapsia garganica, Orlaya maritima, and Retama raetam were investigated. The oil values were more than 26 %, except seeds of R. raetam (ca. 3 %). Unsaturated fatty acids accounted for the majority of the fatty acids (more than 75 %). Oleic and linoleic acid were the predominant fatty acids. Total phenolic compounds (24–104 mg GAE g^?1 DR), total flavonoids (4–102 mg QE g^?1g DR), total tannins (28–85 mg GAE g^?1 DR) and condensed tannins (0.62–131 mg CE g^?1 DR) were also determined. The antioxidant activities using different assays were evaluated. The predominant detected classes were the phenolic acids (42–85 %) and the flavonoids (11–48 %). The major phenolic acids were caffeic, trans‐4‐hydroxy‐3‐methoxycinnamic, p‐coumaric, and gallic acid. The predominant flavonoids were quercetin, luteolin, naringin, apigenin, and kaempferol. This study brings attention to the medicinal importance of these species as a source of oil and antioxidant molecules.     

Dielectric Constant,Metallization Criterion and Optical Properties of CuO Doped TeO2–B2O3 Glasses

Journal of Inorganic and Organometallic Polymers and Materials - Copper oxide doped TeO2–B2O3 glass system with empirical formula;...