Dynamics of Fe(II), sulphur and phosphate in pilot-scale constructed wetlands treating a sulphate-rich chlorinated hydrocarbon contaminated groundwater

Long-term investigations were carried out in two pilot-scale horizontal subsurface flow constructed wetlands (planted and unplanted) with an iron-rich soil matrix for treating sulphate-rich groundwater which was contaminated with low concentrations of chlorinated hydrocarbons. The temporal and spatial dynamics of pore-water sulphide, Fe(II) and phosphate concentrations in the wetland beds were characterized and the seasonal effects on sulphide production and nitrification inhibition were evaluated. The results demonstrated that the pore-water sulphide concentrations gradually increased from less than 0.2 mg/L in 2005 to annual average concentrations of 15 mg/L in 2010, while the pore-water Fe(II) concentrations decreased from 35.4 mg/L to 0.3 mg/L. From 2005 to 2010, the phosphate removal efficiency declined from 91% to 10% under a relatively constant inflow concentration of 5 mg/L. The pronounced effect of plants was accompanied by a higher sulphate reduction and ammonium oxidation in the planted bed, as compared to the unplanted control. A high tolerance of plants towards sulphide toxicity was observed, which might be due to the detoxification of sulphide by oxygen released by the roots. However, during the period of 2009-2010, the nitrification was negatively impacted by the sulphide production as the reduction in the removal of ammonium from 75% to 42% (with inflow concentration of 55 mg/L) correlated with the increasing mean annual sulphide concentrations. The effect of the detoxification of sulphide and the immobilization of phosphate by the application of the iron-rich soil matrix in the initial years was proven; however, the life-span of this effect should not only be taken into consideration in further design but also in scientific studies.     

Shape‐Memory Topographies on Nickel–Titanium Alloys Trained by Embossing and Pulse Electrochemical Machining

The two‐way shape‐memory effect (TWSME) in Nickel–titanium (NiTi) alloys is of interest for applications in aerospace, biomedicine, and microengineering due to its reversible shape recovery. In this study, the authors demonstrate two approaches to obtain switchable surface structures using the TWSME. Samples are structured using two surface geometries by either cold embossing, or pulse electrochemical machining (PECM). After planarization, a change from optically smooth to structured and vice versa is observed. The switch is induced through heating and cooling the sample above and below the phase transformation temperature. The protrusions reflect the pattern applied by the two processes. Both methods are promising for preparation of switchable metallic surfaces on larger areas.     

egoisst: a negotiation support system for electronic business-to-business negotiations in e-commerce

Electronic negotiations can range from simple offer exchanges to complex communicative acts concerning packages of products and services. In contrast to dominant approaches aiming at automating the negotiation process (e.g. auction models), we introduce the notion of negotiation support for human negotiators conducting complex electronic negotiations. The negotiation support system egoisst for business-to-business electronic commerce is presented that is based on theories of communication and information systems and that combines communication and document management. egoisst has been successfully validated for e-negotiations in the construction industry.     

Who talks to whom about what? How interdisciplinary communication and knowledge of expertise distribution improve in integrated R&D labs

Although several studies have examined the impact of open workspaces, there is still an on-going debate about its advantages and disadvantages. Our paper contributes to this debate by shedding light on three issues: the effect of open workspaces on (1) the flow of communication along and across hierarchical lines; (2) the content of communication; and (3) the specificities of open integrated laboratories. Our findings derive from a longitudinal case in a large pharmaceutical company that has relocated some R&D teams from enclosed to multi-space offices and labs. The relocation has resulted in (a) increased interdisciplinary communication, particularly at lower hierarchical levels, (b) a shift of the location of discussions and the content of conversations and (c) an improved knowledge about expertise distribution.

Practitioner Summary: Communication is essential in knowledge-driven organisations. This article examines the impact of a relocation of R&D employees from enclosed to multi-space offices and labs on communication patterns. We explain how the new environment fosters interdisciplinary communication, shifts the location of discussions and increases the knowledge of expertise distribution.     

A Longitudinal Study of Workspace Design for Knowledge Exploration and Exploitation in the Research and Development Process

In order to leverage organizational learning, scholars have already defined but are still discussing the interpretation of two different learning types, exploration and exploitation. Exploring new frontiers across knowledge domains and maintaining the balance with exploiting the existing knowledge is critical for the prosperity of an organization. The spatial dimension of organizational learning considers that proximity of employees has an influence on their learning activities, but from a rather macro perspective without taking workspace design into account. We account for these issues by examining the impact of workspace design on knowledge exploration and exploitation on the micro level at distinct stages along the value chain (i.e., the research, development and project market team unit) of Novartis, a pharmaceutical company. In a longitudinal study, employees of the three cases have been interviewed and observed over the course of three years, before and after workspace redesign. With the change from a cellular to an open workspace, employees become closer and highly visible to each other, which influences knowledge work. As the cases occurred sequentially in time, design principles were derived. The findings suggest that exploitation is supported by workspace design that leads to high proximity inducing faster feedback cycles and first‐hand information. Exploration, however, is supported by workspace design that leads to high visibility triggering more cross‐functional interactions and thereby the variability of knowledge. The later the stage in the research and development process, the higher the need for balanced learning activities. This balance is well reflected in a ‘multi‐space’ workspace consisting of shared meeting areas, quiet zones, central staircases and integrated laboratories and desk areas.     

User Innovation in Techniques: A Case Study Analysis in the Field of Medical Devices

Users are the primary source of new techniques, i.e. systematic activities by which a complex task is accomplished. Even though user‐generated techniques are a pervasive phenomenon which can be observed in many different contexts, existing research on user innovation has focused on product and service innovations. We focus on this important area of user innovation by studying four cases in the field of medical devices to analyse the processes by which users generate and diffuse new techniques as well as the interdependencies between user‐generated techniques and subsequent changes to product use and product innovation. Our findings suggest that user innovation in techniques triggers product innovation by users and manufacturers. Therefore, users' contributions to total innovation output are much higher than previously considered. Additionally, the diffusion of techniques differs significantly from the diffusion of new products. It can only be achieved with the involvement of diffusion agents and their interpersonal interaction and joint performance of the technique with possible adopters. As the diffusion of a technique is often a prerequisite for the diffusion of any related product, companies are forced to re‐think their marketing strategies.     

TiO<Subscript>2</Subscript>-containing and ZnO-containing borosilicate glass—a novel thin glass with exceptional antibiofilm performances to prevent microfouling

Biofilm formation, also known as microfouling, on indwelling medical devices such as catheters or prosthetic joints causes difficult to treat and recurrent infections. It is also the initial step for biocorrosion of surfaces in aquatic environment. An efficient prevention of microfouling is preferable but the development of antibiofilm surfaces is enormously challenging. Therefore, soda-lime, aluminosilicate, and three borosilicate glasses with different TiO₂ and ZnO compositions were investigated on their feasibility to prevent biofilm formation by standardized in vitro biofilm assays using different pathogenic bacteria. Furthermore, the biocompatibility of these glasses was evaluated using eukaryotic cell lines end erythrocytes. Only two borosilicate glasses, containing TiO₂ and ZnO, showed an increased antibiofilm performance inhibiting biofilm adhesion and formation. The biofilm thickness and area were significantly reduced by over 90?% and characterized by diffuse structures. All tested glass types showed neither cytotoxicity nor hemotoxicity. Therefore, the antibiofilm borosilicate-thin glasses are qualified for surface coatings where biofilms are not desirable such as on medical devices.     

On the effect of noisy measurements of the regressor in functional linear models

We consider the estimation of the slope function in functional linear regression, where a scalar response Y is modelled in dependence of a random function X, when Y and only a panel Z ₁,…,Z _L of noisy measurements of X are observable. Assuming an i.i.d. sample of (Y,Z ₁,…,Z _L ) of size n we propose an estimator of the slope which is based on a dimension reduction technique and additional thresholding. We derive in terms of both the sample size n and the panel size L a lower bound of a maximal weighted risk over a certain ellipsoid of slope functions and a certain class of covariance operators associated with the regressor X. It is shown that the proposed estimator attains this lower bound up to a constant and hence it is minimax-optimal. The results are illustrated considering different configurations which cover in particular the estimation of the slope as well as its derivatives.