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Much of the Earth’s biosphere has been appropriated for the production of harvestable biomass in the form of food, fuel and fibre. Here we show that the simplification and intensification of these systems and their growing connection to international markets has yielded a global production ecosystem that is homogenous, highly connected and characterized by weakened internal feedbacks. We argue that these features converge to yield high and predictable supplies of biomass in the short term, but create conditions for novel and pervasive risks to emerge and interact in the longer term. Steering the global production ecosystem towards a sustainable trajectory will require the redirection of finance, increased transparency and traceability in supply chains, and the participation of a multitude of players, including integrated ‘keystone actors’ such as multinational corporations.

It is over a decade since the concept of critical fl ux was introduced. From that time intensive research has been done to fi nd the functionality and dependency of critical fl ux for different feeds and membranes. The studies focussed on critical fl ux in the fi eld of oily water fi ltration are scarce, however, there are numerous membrane units which have been applied to treat wastewater contaminated with oil. It might be due to the fact that in this kind of fi ltration the oil drops form a gel layer on the surface of the membranes and this gel layer formation is not the case with feeds where the concept of critical fl ux has been studied (suspended solids forming a cake layer). In membrane fi ltration of oily water, knowledge on the existence of critical fl ux and the infl uence of different parameters on it may enhance a better operation of the membrane units. In order to fi nd the critical fl ux, a set of experiments was carried out in constant pressure mode using varying pressures from 0.5 to 4 bars. A cycling pressure approach (increasing and decreasing pressure) was applied to fi nd the possible critical fl ux in a system consisting of emulsifi ed oil and salts. It was found that a weak form of critical fl ux in some cases might exist close to the lowest pressure. No strong form of critical fl ux was observed from comparison between pure water and permeate fl ux since the permeate fl ux differed signifi cantly from the initial pure water fl ux even at the lowest pressure. The existence of a limiting fl ux and its dependency on operating conditions was proven in some cases. The limiting fl ux was established under different operating conditions, including oil concentration, pH, temperature, salts and fl ow velocity. The results showed that this fl ux was signifi cantly infl uenced by variations in fl ow velocity and temperature.

Akzo Nobel, Eka Chemicals, produces hydrogen peroxide in a large scale using the anthraquinone (AQ) autooxidation process. The key step is the highly selective liquid-phase hydrogenation of the AQs to their corresponding hydroquinones. For this step, a unique hydrogenation technology employing a monolithic catalyst has been developed and implemented.

The electrophoretic mobilities of hemoglobin and lysozyme were measured through polycarbonate track‐etched membranes of different pore sizes. Together with the zeta potential of the protein‐fouled membranes, and measurements of the free‐solution mobilities, protein sizes, and membrane pore sizes, the theory of Ennis et al. was tested. The presence of the membrane offered little hindrance to protein transfer when the membrane pore size was large in comparison with the protein size and the thickness of the electrical double layers. Under some solution conditions, protein agglomeration was significant and the interactions between the larger particles, and the membrane pore walls caused a more pronounced reduction in the protein mobility from its free‐solution value. Good agreement with the theoretical model was found only for cases where the solution remained as a monodispersed suspension of protein monomers.

Nanofiltration membranes were studied and their suitability for treatment of paper mill total effluent was evaluated. The membrane flux, its decline and retentions of various components were studied on a laboratory scale using a flat sheet module under different operation conditions. The results showed that during short filtrations temperature, pressure and flow velocity had minor effects on the retention of the measured components. Only the retention of monovalent ions (chloride) was significantly dependent on the flow velocity and the ionic concentration on the surface of the membrane. With the Desal-5 membrane, however, temperature, pressure and flow velocity were found to have a considerable effect on the permeate flux. The critical flux of the membranes was dependent on the flow velocity. The higher the flow velocity, the higher the pressure that could be used without a decrease in permeate flux. pH had a considerable effect on the ability of the membranes to retain various species. Increasing the pH of the solutions improved retention ability of the membranes. An increase in salt concentration (Na2SO4and NaCl) decreased the flux and led to a decrease in the retentions of COD and chloride. With the RO membrane (TFC ULP) changes in salt concentration did not significantly alter the retentions. Adjustment of the filtration conditions is one way to improve the efficiency of NF membranes. Appropriate pretreatment of the waste water can also improve the flux and filtering efficiency. The permeates from the NF membranes were adequately clean to be reused, for example, as shower waters.

The paper describes how an error-free reduction in robot downtime is obtained by introducing system adaptivity. This was achieved by developing an application package for assembly tasks, using special error detection & recovery routines and off-line programming. All work has been carried out on the known Mark II automatic small-batch assembly system, also developed in-house. Our application package runs off a rule-based system. Off-line programming is made feasible by cell calibration techniques.

Capillary filtration technology has been developed in Finland by Outokumpu Mintec Oy. Almost ten years of full scale experience of capillary filtration has shown that this type of filter is a very profitable and very economical solution to many filtration problems. The main area where capillary filters are used is in the dewatering of mineral concentrates. Both vacuum capillary as well as pressurised capillary filters are now commercially available. In the work reported here, the effect of flocculants on the capacity of Ceramec filters is studied. The titrations were made using three copper concentrates and a laboratory-scale automatic dipping machine. During the experiments no permanent plugging of ceramic filter media was observed. On the contrary, small concentrations of non-ionic or slightly anionic flocculants increased the capacity. However, too high a concentration of flocculants caused plugging of the ceramic plates. There were also remarkable differences between the copper concentrates used and their behaviour during filtration with Ceramec filters. Storage of copper concentrates changes their zeta potential very dramatically. In addition, the type of copper sample has an effect on the capacity. Clearly better capacities were achieved using a slurry sample which was brought straight from the mine, compared with using a copper sample which was first dewatered in a mining enrichment plant. The results show that these kinds of experiments should be performed in the mineral concentration plant if very accurate results are desired. A good way to predict the capacity and the cake moisture of mineral concentrates is to perform test filtrations using small, pilot-scale capillary action filters which can be directly connected to the mineral concentration process.

The present study concerns the deformation behaviour of two austenitic stainless steels (base composition corresponding to 316L) with two different nitrogen levels, 0.14 and 0.29 wt-% respectively. The influence of grain size on the mechanical properties has been investigated. The grain size dependence of the monotonic as well as the cyclic stress-strain curves were shown to follow a Hall-Petch type relationship. The influence of the grain size was found to be lower for the cyclic thanfor the mOnotonic yield stresses. The lower grain size sensitivity of the cyclic yield stresses can be explained by the successive breakdown of the planar slip mode during cyclic straining. For both static and cyclic deformation modes the dependence of grain size increases with higher nitrogen content. Dislocation structures of the various conditions were studied with transmission electron microscopy and related to the mechanical behaviour of the two materials.

During daily work in hospitals a large amount of clinical data is produced each day. Totally computerized patient records are not yet widely used but a large part of essential information is already stored on computer files. These include laboratory test results, diagnoses, codes for operations, codes of histopathological diagnoses and maybe even the patient's medication. Accordingly, these databases include much clinical knowledge that would be useful for clinicians.Laboratories try to support clinicians by producing reference values for laboratory tests. It is, of course, necessary information but, however, it does not give very much information about the weight of evidence that an abnormal laboratory test will give in special clinical settings.We have developed a software package - DiagaiD - in order to build a smart link between patient databases and clinicians. It utilizes neural network-based machine learning techniques and can produce decision support which meets the special needs of clinicians. From example cases it can learn clinically relevant transformations from original numeric values to logical values. By using data transformation together with a single layer perceptron it is possible to build nonlinear models from a set of preclassified example cases.In this paper, we use two small datasets to show how this scheme works in the diagnosis of acute appendicitis and in the diagnosis of myocardial infarction. Results are compared with those obtained using logistic regression or backpropagation neural networks. The performance of our neuro-fuzzy tool seemed to be slightly better in these two materials but the differences did not reach statistical significance.

This paper describes the result of a complete parameterization of the activities in Mark II (Skantze, 1988; Holmstedt, 1989) FAA-cell using the subbatch-principle. All data concerning products, parts, fixtures, paths, grippers, external equipment and the system itself is stored in a number of databases. A small core of code then works upon these data until all data is exhausted. From the users point of view, there is no code or sequence of statements what so ever. Instead, the user controls an application program for assembly where much of the necessary knowledge about assembly is expressed in the rules in the code. The rules are often of a trivial nature: firstgrasp the part - theninsert it, i.e. the order of many of the actions are easy to predict and does not have to be teached again and again. As a result, we introduced a completely new product (seven different parts) to our FAA pilot facility in less than four hours.

Synthetic chemicals and biologically engineered materials are major forces in today's food systems, but they are also major drivers of the global environmental changes and health challenges that characterize the Anthropocene. To address these challenges, we will need to increase assessment activity, promote alternative production practices with less reliance on such technologies, and regulate social campaigns and experiments., Competing Interests: L.J.G. serves on the EAT Foundation Board of Trustees and on the Global Resilience Partnership Advisory Board., (© 2022 The Authors.)