Comparison and optimization of different methods of evaluation of displacements in cracked reinforced concrete beams

The evaluation of deflections of reinforced concrete beams is strongly affected by the cracking of concrete; in order to develop a correct calculation of deflections, it is necessary to define an adequate tension stiffening model and exact, prediction of the values of cracking moment and of Young's modulus of elasticity. In this paper, the different models of tension stiffening and the semi-empirical correlations for evaluating the modulus of rupture and the Young's modulus are synthetically described and compared with each other. The analytical deflections computed by means of different models are compared with the experimental results obtained by different authors, and an optimization analysis is developed in order to improve the CEB and ACI models.     

A Network Protocol Stack in Standard ML

The FoxNet is an implementation of the standard TCP/IP networking protocol stack using the Standard ML (SML) language. SML is a type-safe programming language with garbage collection, a unique and advanced module system, and machine-independent semantics. The FoxNet is a user-space implementation of TCP/IP that is built in SML by composing modular protocol elements; each element independently implements one of the standard protocols. One specific combination of these elements implements the standard TCP/IP stack. Other combinations are also possible and can be used to easily and conveniently build custom, non-standard networking stacks. This paper describes in detail the final design and implementation of the FoxNet, including many of the details that are crucially affected by the choice of SML as the programming language.     

Effects of carbonaceous nanoparticles from low-emission and older diesel engines on human skin cells

Diesel exhaust particles (DEP) are major constituents of ambient air pollution and are associated with respiratory and cardiovascular diseases as well skin cell alterations in vitro. The epidermal cells are among the first cell populations exposed to chemical pollutants, including DEP, and are an important source of pro-inflammatory mediators. We evaluated the effects of carbonaceous soot particles from current low-emission (Euro IV) diesel engines on the oxidative and inflammatory response of normal human skin cells and compared the results with those induced by carbonaceous soot particles from an older diesel engine (BS) operating under black smoke conditions. We observed that both soot nanoparticles were spontaneously internalised by keratinocytes and distributed mostly around the cell nucleus. Moreover, at the same mass concentration, Euro IV soot particles exhibited a much higher oxidative, pro-fibrotic and toxic potential on these cell types than soot particles from the older diesel engine. These results are in agreement with and confirm our previous findings on human macrophage cells and strengthen the assumption that, at the same mass concentration, soot particles produced under low emission conditions are more cytotoxic than particles from the older diesel engine. This effect could be assigned to the defective surface structure of Euro IV diesel soot, rendering it highly active. Our findings highlight that the reduction of soot emission in terms of mass does not automatically lead to a reduction of the dangerous effects and show that soot particles from different diesel engines possess different biological behaviour towards human cells.     

Effect of standard phenolic compounds and olive oil phenolic extracts on acrylamide formation in an emulsion system

In this work the effect of standard phenolic compounds such as trolox, phenolic acids (ferulic, gallic, protocatechuic and caffeic acid) and secoiridoids, extracted from virgin olive oil (VOO), on acrylamide formation in an emulsion system was investigated. The emulsion system was heated in an oil bath at different temperatures and for different periods of time. At 105 and 115 °C the generated amounts of acrylamide were negligible during the monitoring time. At 125 °C addition of standard phenolic compounds reduced acrylamide formation which was more pronounced at initial time of heating (20 min) reaching up to 70%. Protocatechuic and gallic acid were more effective than trolox, caffeic and ferulic acid in acrylamide reduction at the final time intervals of heating (30–60 min). On the contrary, addition of VOO extract in the emulsion system resulted in a remarkable increase of acrylamide level, which was ascribed to secoiridoids’ structure containing aldehydic groups.     

Characterization of Conventional,Biodynamic, and Organic Purple Grape Juices by Chemical Markers,Antioxidant Capacity,and Instrumental Taste Profile

The objectives of this study were to characterize organic, biodynamic, and conventional purple grape juices (n = 31) produced in Europe based on instrumental taste profile, antioxidant activity, and some chemical markers and to propose a multivariate statistical model to analyze their quality and try to classify the samples from the 3 different crop systems. Results were subjected to ANOVA, correlation, and regression analysis, principal component analysis (PCA), hierarchical cluster analysis (HCA), soft independent modeling of class analogy (SIMCA), and partial least‐squares discriminant analysis (PLSDA). No statistical significant differences (P > 0.05) were observed among juices from the 3 crop systems. Using PCA and HCA, no clear separation among crop systems was observed, corroborating the ANOVA data. However, PCA showed that the producing region highly affects the chemical composition, electronic tongue parameters, and bioactivity of grape juices. In this sense, when organic and biodynamic were grouped as “nonconventional” juices, SIMCA model was able to discriminate 12 out of 13 organic/biodynamic juices and 17 out of 18 conventional juices, presenting an efficiency of 93.5%, while 11 out of 13 non‐conventional and 100% conventional grape juices were correctly classified using PLSDA. The use of electronic tongue and the determination of antioxidant properties and major phenolic compounds have shown to be a quick and accurate analytical approach to assess the quality of grape juices.     

Photocatalytic degradation of acid blue 80 in aqueous solutions containing TiO2 suspensions

The photocatalytic degradation of the anthraquinonic dye Acid Blue 80 in aqueous solutions containing TiO2 dispersions has been investigated. The process has been monitored by following either the disappearance of the dye (via HPLC) and the formation of its end-products (via IC, GC, and TOC analysis). Although a relatively fast decolorization of the solutions has been observed, the mineralization is slower, and the presence of residual organic compounds was evidenced even after long term irradiation, confirming the relevant stability of anthraquinone derivatives. The identification of various unstable intermediates formed after low irradiation times was performed by HPLC-MS, allowing us to give insight into the early steps of the degradation process which mainly involve C-N bonds breaking and substrate hydroxylation. Complete and relatively fast mineralization of the substrate was achieved by irradiating the semiconductor dispersions in the presence of added K2S2O8.     

Disperse and cationic dyes from 2-(o,m, p-Aminophenyl)oxazolo [4,5-b]pyridine

2-(o,m,p-Aminophenyl)oxazolo[4,5-b]pyridines were diazotized and coupled with N,N-disubstituted anilines, giving monoazo dyes suitable for polyamide fabrics. Some of the dyes were quaternized to give cationic dyes for acrylic fibres. The colour of dyed materials was assessed in terms of tristimulus colorimetry. Electronic spectra of the amines and NMR spectra of the cationic dyes are briefly discussed.     

ENERGY LEVELS AND RADIATIVE TRANSITIONS IN MUONIC HYDROGEN

The physics of muonic hydrogen is a powerful tool to test QED at short distances and—assuming the validity of QED—to probe the properties of the proton, deuteron, and triton at low momentum transfer. This paper contains several tables that are useful in planning experiments on muonic hydrogen.     

Knowledge-Based Jobs and the Boundaries of Firms Agent-based Simulation of Firms Learning and Workforce Skill Set Dynamics

The article explores emergence and survival of human resource management strategies and organisational types in a knowledge-based job market. The analysis considers a dynamic environment in which skill requirements change rapidly. We built an agent-based model to simulate a market where firms post job offers to fill vacancies and decide how to select and reward employees; employees, bearing skills, select firms comparing job offers. Taking an evolutionary approach, we explore how hiring strategies, which guarantee survival, emerge from interconnected variation, selection and retention processes. The simulation experiments suggest that, as the rate of change of the environment increases, long-term employment and firm-specific knowledge building emerge as the survival strategy.