Bioactive glass–ceramic coated titanium implants prepared by electrophoretic deposition

Surface modification of Ti alloys towards an improved osteoinductive behaviour is one of the major challenges in orthopaedic implant technology nowadays. One way to achieve this is by applying a bioactive coating which can increase the rate of osseointegration and chemical bonding of surrounding bone to the implant. In the present work, the production of a bioactive glass–ceramic coating on flat Ti alloys by electrophoretic deposition is demonstrated. The coatings are applied by cathodic deposition from non-aqueous suspensions followed by sintering in vacuum, avoiding uncontrolled oxidation of the Ti substrates. The use of non-aqueous suspensions both allowed to reduce the deposition time and yielded homogeneous coatings with a uniform thickness of 8 μm. Evaluation of the coating adhesion confirmed the good mechanical performance of the coatings with a tensile bond strength of 41.0 ± 11.1 MPa. Additionally, a feasibility study demonstrated the potential of electrophoretic deposition as a coating technique for commercial complex implants.     

Tailoring materials properties of UFG aluminium alloys by accumulative roll bonded sandwich-like sheets

Accumulative roll bonding (ARB) as a method of severe plastic deformation is a well-established process to produce ultrafine-grained (UFG) sheet materials with extraordinary mechanical properties. In this work ARB is applied to combine different sheet materials in order to tailor the materials properties by producing sandwich-like structures. The high strength aluminium alloy AA5754, after 4 ARB cycles (N4), is used as a core material. To achieve high corrosion resistance and good visual properties, it is cladded with commercially pure aluminium AA1050A (N4) at room temperature and alternatively with AA6014 (N4) at 230 °C. All materials are UFG and satisfactory bonding between the different layers of aluminium alloys is achieved. Nanoindentation measurements reveal that there is a sharp transition in hardness at the interface. The yield and tensile strength of the core material are fully retained in the case of the AA6014/AA5754 sandwich. The strength of the AA1050A/AA5754 sandwich is slightly lower compared to the core material but still twice as high as the clad material. The serrated yielding effect which is strongly visible in tensile tests on the pure AA5754 alloy completely disappears in the sandwich sheets, which means the surface quality is strongly enhanced.     

Challenges when implementing BIM for industry change

Public clients have been identified as drivers of architectural, engineering and construction (AEC) industry change through their implementation of building information modelling (BIM). Yet, little is known of this implementation process and the associated challenges. This study aims to increase the understanding of what intra- and inter-organizational challenges that arise when a large Swedish public infrastructure client implements BIM to change the work practices of the actors in the Swedish AEC industry. The IT business value model allows for understanding the public client’s implementation of BIM as an IT-supported change process and for understanding the associated intra- and inter-organizational challenges. The findings show nine categories of intra- and inter-organizational challenges related to, for example, demanding BIM in procurement and creating incentives for BIM implementation. The findings show that intra-organizational challenges related to a top-down implementation of BIM, while inter-organizational challenges related to a bottom-up implementation. The impact of these challenges on the public client’s ability to drive AEC industry change by implementing BIM is discussed. The findings contribute with the client perspective to studies on BIM implementation and with an increased understanding of the challenges associated with implementing IT-supported change processes.     

Hydro energy potential of cooling water at the thermal power plant

The hydro energy of the gravity water flow from the coal-fired thermal power plant units to the river in an open cooling system of turbine condensers is determined. On the basis of statistical data for a long time period, the water net head duration curve due to the river annual level change, as well as the reduction of the hydro energy potential due to the thermal power plant overhauls periods, are evaluated in the case study of the Thermal Power Plant “Nikola Tesla B” in Serbia. A small hydro power plant is designed for the utilization of this hydro energy, and the economic benefits of the project are calculated. The internal rate of returns and pay back periods are calculated in dependence of the electricity price and total investment costs. The increase of profitability is assessed, bearing in mind that the plant might be realized as the Clean Development Mechanism project according to the Kyoto protocol. The obtained results show that the project is economically attractive, and it can be carried out with standard matured solutions of hydro turbines available at the market. Even for the relatively low electricity price from small hydro power plants in Serbia of 0.08 €/kW h the internal rate of return and the pay back period are 17.5% and 5.5 years.     

Relations between spouses' depressive symptoms and marital conflict: A longitudinal investigation of the role of conflict resolution styles.

This study investigated longitudinal relations between spouses' depressive symptoms and styles of conflict resolution displayed by husbands and wives in marital conflict, including angry, depressive, and constructive patterns of expression. Behavioral observations were made from a community sample of 276 couples during marital conflict resolution tasks once a year for 3 years. Couples were observed engaging in a major and minor conflict resolution task. Constructive, angry, and depressive conflict resolution styles were derived from the behavioral observation coding. Couples self-reported on depressive symptoms and marital dissatisfaction. Path analyses provided support for an extension of the marital discord model of depression (Beach, Sandeen, & O'Leary, 1990). Specifically, angry, depressive, and constructive styles of conflict each mediated the link between marital dissatisfaction and depressive symptoms. Significant cross-spouse effects were found. Implications for the treatment of depressed and/or relationally discordant couples are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Co-occurrence of ochratoxin A and citrinin in unprocessed cereals established during a three-year investigation period

The aim of this study was to investigate ochratoxin A (OTA) and citrinin (CIT) co-occurrence in different unprocessed cereals (n = 189) originating from Croatia during a three-year investigation period (2014–2016) using validated enzyme immunoassay (ELISA) methods. CIT and OTA were determined in 49% and 7% of samples, respectively. Significantly higher (p < 0.05) overall mean concentrations were determined for CIT (66.8 ± 76.0 µg/kg) in comparison to OTA (5.2 ± 1.1 µg/kg). Based on the analysis of all investigated cereals, CIT was found about 15 times more frequently than OTA and in similarly (15-fold) higher concentrations, irrespective of the cultivation year. The results revealed a moderately positive correlation between OTA and CIT concentrations in maize (r_s = 0.44) and wheat (r_s = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant.