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Natural rubber (NR) is valuable material of natural origination with growing demand worldwide. Thus, the methods for NR property improvement are continuously developed. The article will be focused on methods of chemical modification of NR and the use of improved traditional fillers such as carbon black (CB) and silica. Modification reactions include epoxidation, hydrogenation, and grafting vinyl monomers onto NR molecules. Some methods of surface modification of NR film were also reviewed. Thanks to modification the NR degree of unsaturatiton is decrease that leads to its enhanced aging resistance. Besides, grafted functional groups may impart new, never met before properties to NR. Application of modified traditional fillers obviously increase their reinforcement possibility, particularly mechanical. Also, cellulose as a potential reinforcing filler is considered due to its ability to meet requirement of environment protection while keep the mechanical properties of NR products at acceptable high level.

In the present work, ZnO nanoparticles (NPs) was modified with stearic acid (SA) to form ZnO‐SA and subsequently used as an activator for natural rubber vulcanization. Modified ZnO NPs were characterized by FTIR, X‐ray diffraction, SEM, and contact angle measurement. ZnO‐SA NPs were used in the vulcanization of natural rubber (NR) and compared with unmodified ZnO NPs. It was found that ZnO‐SA NPs decreased scorch time and activation energy of the vulcanization process compared to unmodified ZnO NPs. Mechanical performances of NR vulcanized with ZnO‐SA NPs and ZnO NPs were characterized by tensile properties, hardness shore A, compression set, permanent set, and rebound resilience. ZnO‐SA NPs not only increased the vulcanization process of NR but also improved the mechanical properties. This was interpreted as an increment in crosslinking density and better compatibility of ZnO‐SA NPs with NR.

The most popular additive manufacturing (AM) technologies to produce titanium alloy parts are electron beam melting (EBM), selective laser melting (SLM) and directed energy deposition (DED). This investigation explores mainly these three techniques and compares these three methods comprehensively in terms of microstructure, tensile properties, porosity, surface roughness and residual stress based on the information available in the literature. It was found that the microstructure is affected by the highest temperature generated and the cooling rate which can be tailored by the input variables of the AM processes. The parts produced from EBM have strength comparable to that of conventionally fabricated counterparts. SLM and DED yield superior strength, which can be up to 25% higher than traditionally manufactured products. Due to the presence of larger tensile residual stress, surface roughness and porosity, AM fabricated parts have lower fatigue life compared to those of from traditional methods. EBM parts have slightly lower fracture toughness (i.e., lower fatigue life) than conventionally produced parts while SLM and DED have significantly lower fracture toughness. Annealing, hot isostatic pressing, stress relief and additional machining processes improve the characteristics of parts produced from AM. Ti–6Al–4V alloy parts fabricated via AM may have limited applications despite the high demands in aerospace or biomedical engineering. Since rapid product development using 3D printers leads to significant cost reductions more recently, it is expected that more opportunities may soon be available for the AM of titanium alloys with newer AM processes such as cold spray additive manufacturing (CSAM) and additive friction stir deposition (AFSD).

For prediction of tensile strength of combine aged NR/CR blends, samples with NR/CR ratios of 100/0, 95/5 and 90/10 were subjected heat aging at various temperatures, namely 100, 110 and 120°C, each for 22 h, followed by dynamic tensile loadings to 140 % and frequency 300 cycles/min. Then the tensile strengths of aged samples were defined. Based on obtained experimentally values the experimental statistical model was built using FORTRAN language. The model result in prediction equation for tensile strength of NR and NR/CR blends with low CR (not higher 10 %) contents. This equation seems to have fine usability, having relative error between calculated and experimentally defined values of tensile strength less than 10 % in the considered range of experiments.

IL‐12 (p35/p40) and IL‐23 (p19/p40) signal through IL‐12R (IL‐12Rβ2/β1) and IL‐23R (IL‐23Rα/IL‐12Rβ1), respectively, which can promote pathogenic T lymphocyte activation, differentiation, and function in graft‐versus‐host disease (GVHD). With the use of murine models of allogeneic hematopoietic cell transplantation (HCT), we found that IL‐12Rβ1 on donor T cells was dispensable to induce acute GVHD development in certain circumstances, while IL‐23Rα was commonly required. This observation challenges the current paradigm regarding IL‐12Rβ1 as a prerequisite to transmit IL‐23 signaling. We hypothesized that p19/EBI3 (IL‐39) may have an important role during acute GVHD. With the use of gene transfection and immunoprecipitation approaches, we verified that p19 and EBI3 can form biological heterodimers. We found that IL‐39 levels in recipient serum positively correlated with development of acute GVHD in experimental models and in clinical settings, thereby implicating IL‐39 in the pathogenesis of acute GVHD. Furthermore, we observed that human T cells can signal in response to IL‐39. In chronic GVHD, IL‐23Rα and IL‐12Rβ1 were similarly required for donor T cell pathogenicity, and IL‐39 levels were not significantly different from controls without GVHD. Collectively, we identify a novel cytokine, IL‐39, as a pathogenic factor in acute GVHD, which represents a novel potential therapeutic target to control GVHD and other inflammatory disorders. In murine models as well as in patients, interleukin‐23Rα can signal independently of interleukin‐12Rβ1 on donor T cells and interleukin‐39 may potentiate T cell pathogenicity in the development of graft‐versus‐host disease.

IL-12 (p35/p40) and IL-23 (p19/p40) signal through IL-12R (IL-12Rβ2/β1) and IL-23R (IL-23Rα/IL-12Rβ1), respectively, which can promote pathogenic T lymphocyte activation, differentiation, and function in graft-versus-host disease (GVHD). With the use of murine models of allogeneic hematopoietic cell transplantation (HCT), we found that IL-12Rβ1 on donor T cells was dispensable to induce acute GVHD development in certain circumstances, while IL-23Rα was commonly required. This observation challenges the current paradigm regarding IL-12Rβ1 as a prerequisite to transmit IL-23 signaling. We hypothesized that p19/EBI3 (IL-39) may have an important role during acute GVHD. With the use of gene transfection and immunoprecipitation approaches, we verified that p19 and EBI3 can form biological heterodimers. We found that IL-39 levels in recipient serum positively correlated with development of acute GVHD in experimental models and in clinical settings, thereby implicating IL-39 in the pathogenesis of acute GVHD. Furthermore, we observed that human T cells can signal in response to IL-39. In chronic GVHD, IL-23Rα and IL-12Rβ1 were similarly required for donor T cell pathogenicity, and IL-39 levels were not significantly different from controls without GVHD. Collectively, we identify a novel cytokine, IL-39, as a pathogenic factor in acute GVHD, which represents a novel potential therapeutic target to control GVHD and other inflammatory disorders.

A certified reference material, NIMD-01, was developed for the analysis of mercury speciation in human hair. We collected the hair of Vietnamese males from a barbershop in Hanoi in 2016 and prepared 1200 bottles containing 3 g of sieved and blended hair powder. The certified value was given on a dry-mass basis, with the moisture content obtained by drying at 85°C for 4 h. Certified values with the expanded uncertainties (coverage factor, k= 2) were as follows: methylmercury, 0.634 ± 0.071 mg kg−1as mercury; total mercury, 0.794 ± 0.050 mg kg−1; copper, 12.8 ± 1.4 mg kg−1; zinc, 234 ± 29 mg kg–1; selenium, 1.52 ± 0.29 mg kg–1. An indicative arsenic concentration of 0.17 ± 0.03 mg kg–1was measured. Extended uncertainties were estimated by sample homogeneity, long- and short-term stabilities, and a characterization from measurements made by collaborating laboratories.

Oral and maxillofacial trauma frequently results in both hard and soft tissue injuries. This case report presents a 3-year-old patient who developed a lower-lip abscess due to foreign bodies two months post-trauma. Clinical examination revealed swollen masses in the skin and mucosa of the lower lip. After diagnosing the abscess, the foreign body was removed, leading to full recovery. This case emphasizes the importance of thorough clinical examination, detailed medical history, appropriate paraclinical testing, and the use of ultrasound as a superior diagnostic tool, given its safety, non-invasiveness, and diagnostic efficacy, especially when X-rays are inconclusive.

In the article, the effects of silica (silicon oxide) on some properties of natural rubber (NR) were studied. Silica used are unmodified (SiKBT) and modified with triethoxi silane propyl tetrasunfite (SiBT). It is shown SiBT increases vulcanization network density (VND), so it enhances strength and elastic properties of NR. In contrary, SiKBT decreases VND and reduces, but has almost no effect on strength of NR. Silica, both modified and unmodified, are assumed to improve network regularity of NR that change thermal degradation behavior of materials and keep the strength of NR‐SiKBT compound unchanged.

Computer aided hardware/software partitioning is one of the key challenges in hardware/software co-design. This paper describes a new approach to hardware/software partitioning for a synchronous communication model including multiple hardware devices. We transform the partitioning into a reachability problem of timed automata. By means of an optimal reachability algorithm, the optimal solution can be obtained with limited resources in hardware. To relax the initial condition of the partitioning for optimization, two algorithms are designed to explore the dependency relations among processes in the sequential specification. Moreover, we propose a scheduling algorithm to improve the synchronous communication efficiency further after partitioning stage. Some experiments are conducted with the model checker UPPAAL to show our approach is both effective and efficient.

The reaction of iodine, electrogenerated from iodide, is used for the detection of As(III) via electrocatalytic reaction in the diffusion layer of a boron‐doped diamond electrode. The merits of this electrode material for this purpose (over platinum, gold or glassy carbon) are demonstrated and the kinetics of the reaction between I2and As(III) in acid reported.

We present a complete axiomatisation of the operator of projection onto state in the Duration Calculus (DC) relative to validity in DC without extending constructs. Projection onto state was introduced and studied extensively in our earlier works. We first establish the completeness of a system of axioms and proof rules for the operator relative to validity in the extension of DC by neighbourhood formulas, which express the neighbourhood values of boolean DC state expressions. By establishing a relatively complete axiomatisation for the neighbourhood formulas in DC, we then achieve completeness of our system relative to basic DC.

Experimental and theoretical investigations of yarn-object interactions are presented in this paper. The behavior of the yarn—tensioning and drop off—is studied, taking into account several factors such as yarn length, yarn tension, object speed, object orientation. and object profile. A comparison of theoretical predictions and experimental measure ments for different yams indicates good agreement. The theoretical model can be used to optimize the object profile in order to reduce interactive yarn tension.

This paper presents an investigation of the dynamic behaviour of a yarn in an interaction with a high-speed object, for the lower warp sheet during the weaving process. The yarn movement on the object can be described in four stages from non-contact, contact, drop-off and withdrawal. A model is developed to predict this interaction, taking into account several factors such as yarn length, yarn tension, object speed, object orientation and object profile. A comparison of theoretical predictions and experimental measurements for different yarns indicates a good agreement. The theoretical model can be used to optimise the object profile in order to reduce the interactive yarn tension and to avoid any yarn damage.

This paper deals with dependability of imperfect implementations concerning given requirements. The requirements are assumed to be written as formulas in Duration Calculus. Implementations are modelled by continuous semi-Markov processes with finite state space, which are expressed in the paper as finite automata with stochastic delays of state transitions. A probabilistic model for Duration Calculus formulas is introduced, so that the satisfaction probabilities of Duration Calculus formulas with respect to semi-Markov processes can be defined, reasoned about and calculated through a set of axioms and rules of the model.