Quantitative image analysis for the characterization of microbial aggregates in biological wastewater treatment : a review

Quantitative image analysis techniques have gained an undeniable role in several fields of research during the last decade. In the field of biological wastewater treatment (WWT) processes, several computer applications have been developed for monitoring microbial entities, either as individual cells or in different types of aggregates. New descriptors have been defined that are more reliable, objective, and useful than the subjective and time-consuming parameters classically used to monitor biological WWT processes. Examples of this application include the objective prediction of filamentous bulking, known to be one of the most problematic phenomena occurring in activated sludge technology. It also demonstrated its usefulness in classifying protozoa and metazoa populations. In high-rate anaerobic processes, based on granular sludge, aggregation times and fragmentation phenomena could be detected during critical events, e.g., toxic and organic overloads. Currently, the major efforts and needs are in the development of quantitative image analysis techniques focusing on its application coupled with stained samples, either by classical or fluorescent-based techniques. The use of quantitative morphological parameters in process control and online applications is also being investigated. This work reviews the major advances of quantitative image analysis applied to biological WWT processes.The authors acknowledge the financial support to the project PTDC/EBB-EBI/103147/2008 and the grant SFRH/BPD/48962/2008 provided by Fundacao para a Ciencia e Tecnologia (Portugal)

Multimodal Cooperative Resolution of Referential Expressions in the DENK System

We present an approach to the resolution of multimodal referential expressions in a cooperative human-machine communication setting, provided by the DenK system. We discuss how references involving multiple modalities are resolved, and we also indicate how the system can respond cooperatively in case the resolution process fails

Dynamics of plasma catecholamine and corticosterone concentrations during reinforced and extinguished operant behavior in rats

Plasma noradrenaline (NA), adrenaline (A) and corticosterone (CS) concentrations were determined simultaneously in permanently heart-cannulated rats before and during the performance of reinforced and nonreinforced (extinguished) operant behavior. Shortly before the experimental food-reinforced (VI 15-sec schedule) lever-pressing task, anticipatory elevations of plasma NA and CS contents were observed. During reinforced lever responding plasma NA increased, A did not change and CS declined. Extinction was associated with a transient increase in A, decreasing NA and elevated CS concentrations. In addition, a relationship was found between individual lever-pressing rate, neurosympathetic and adrenomedullary reactivity and the degree of schedule-induced polydipsia. The results indicate that presence and absence of expected behavioral consequences (controllability and loss of control, respectively) are attended by selective, but highly dissociated patterns of neurosympathetic, adrenomedullary and adrenocortical output. Collectively, the findings reinforce the concept that distinctive emotional and/or motivational states are associated with different patterns of neuroendocrine responses. The reactivity of the sympathoadrenomedullary component is heavily dependent upon a rat's individual behavioral strategy

Subthreshold symptoms and obsessive-compulsive disorder: evaluating the diagnostic threshold

In this study we compared subjects with obsessive and/or compulsive symptoms who did not meet all criteria for obsessive-compulsive disorder (OCD) (subthreshold subjects) to subjects with full-blown OCD and also to subjects without obsessions or compulsions. The data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), a large representative sample of the general Dutch population (n=7076). Using the Composite International Diagnostic Interview, Version 1.1 (CIDI 1.1), three groups were distinguished: subjects without lifetime obsessions or compulsions (94.2%), subthreshold subjects (4.9%) and subjects with full-blown OCD according to DSM-III-R (0.9%). These three groups were compared on various items, including psychological vulnerability, health and functional status, psychiatric co-morbidity and seeking treatment. Subthreshold and OCD subjects had similar scores on the majority of the items measured. Thus, there was little difference between subthreshold and OCD subjects in health, functional status, psychological vulnerability and psychiatric co-morbidity. However, OCD and subthreshold subjects scored worse on most of these items when compared to the controls without obsessions or compulsions. Having obsessions and compulsions is associated with substantial suffering and disability. Most subjects with obsessions and/or compulsions are not diagnosed with OCD according to the DSM-III-R criteria although these subjects generally display similar consequences to full-blown OCD subjects. We recommend that these subthreshold cases receive special attention in the development of DSM-

On the use of catalysis to bias reaction pathways in out-of-equilibrium systems

Catalysis is an essential function in living systems and provides a way to control complex reaction networks. In natural out-of-equilibrium chemical reaction networks (CRNs) driven by the consumption of chemical fuels, enzymes provide catalytic control over pathway kinetics, giving rise to complex functions. Catalytic regulation of man-made fuel-driven systems is far less common and mostly deals with enzyme catalysis instead of synthetic catalysts. Here, we showviasimulations, illustrated by literature examples, how any catalyst can be incorporated in a non-equilibrium CRN and what their effect is on the behavior of the system. Alteration of the catalysts' concentrations in batch and flow gives rise to responses in maximum conversion, lifetime (i.e.product half-lives andt90 - time to recover 90% of the reactant) and steady states.In situup or downregulation of catalysts' levels temporarily changes the product steady state, whereas feedback elements can give unusual concentration profiles as a function of time and self-regulation in a CRN. We show that simulations can be highly effective in predicting CRN behavior. In the future, shifting the focus from enzyme catalysis towards small molecule and metal catalysis in out-of-equilibrium systems can provide us with new reaction networks and enhance their application potential in synthetic materials, overall advancing the design of man-made responsive and interactive systems.ChemE/Advanced Soft Matte