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In this study membrane filtration, ultrafiltration, and nanofiltration alone and as part of hybrid processes are considered as means to purify pulp and paper mill process waters suitable for reuse. Thermophilic aerobic biological treatment, pH adjustment, flocculation, and ozonation were tested as pretreatment methods on pilot or on laboratory scale. The aim was to increase flux and reduce fouling by various pretreatment steps and, thus, increase the competitiveness of the membrane process. The results were also evaluated by comparing the benefits obtained against the costs. It was discovered that benefits could be obtained with all the pretreatments tried. Thermophilic aerobic biology assisted in the removal of organic material and increased flux significantly, but the costs were the highest. The most cost-effective processes, however, seem to be pH-adjusted nanofiltration and flocculation nanofiltration hybrid processes, which is understandable because of their significantly lower investment costs compared to, for example, those of biological process. The pH adjustment increased the electrostatic repulsion between negatively charged solutes and membrane, thereby increasing the flux. Flocculation removed the foulants effectively from the feed and it both increased flux and reduced fouling. Yet, many noteworthy benefits were obtained also with ultrafiltration and ozonation. All of the hybrid processes tested could be applied at various points of the water circuit of an integrated pulp and paper mill for purification purposes. The eventual superiority and cost-effectiveness of the applied process remains to be determined case by case.

This article synthesizes research on resilience theory and its implications for prevention interventions to increase resilience in high-risk children and adolescents. In addition, this response to both the articles by Drs. Greenberg and Dishion summarizes their key points. Their papers discuss the neuroscience substrate behind two major mediators of antisocial behaviors, namely lack of self-regulation and executive function problems. In addition, we present an overall Resilience Framework that will help the reader organize the aspects of resilience discussed by these two researchers into a transactional process model. This article extends prior researchers' suggestion that resilience is the product of the interaction of genetic, biological, and environmental precursors to a further consideration of higher-level cognitive precursors, such as purpose in life and existential meaning. The relevance of resilience to the prevention of negative outcomes in high-risk children of alcoholics (COAs) and substance abusers is covered. Within this third wave of resilience research on prevention interventions, we present data suggesting that family strengthening approaches have the greatest impact on increasing resilience.

The hypothesis is advanced that behavioral and physiologic resilience develops in part from infants' and young children's experience coping with the inherent normal stress of daily life and social interaction. Data on the stress of normal social interactions and perturbated interactions from the Face-to-Face Still-Face Paradigm (FFSF) are presented for young infants. These findings, including behavioral, heart rate and vagal tone, and electrodermal reactivity demonstrate the stress inherent in normal interaction and how coping with normal stress develops infants' coping with more intense environmental and social stressors.

When conceptualized within a developmental systems theoretical framework, resilience involves mutually beneficial, reciprocally influential relations between a person and his or her context. The key features of developmental systems theory, which stress the plasticity of these relations, lead to an optimistic view of the possibility of promoting positive human development (PHD) across the life span. The results of recent longitudinal research about adolescent development allow this period to serve as a sample case of how positive development is associated with the alignment of the strengths of individuals with ecological resources for healthy growth.

The significance of psychosocial stress and ways of coping with stress for understanding resilience in childhood and adolescence are reviewed. Psychological and biological processes of reactivity to and recovery from stress are central in understanding the physical and emotional tolls that result from prolonged exposure to chronic stress. A central theme of this article is that stress exerts a double toll on physical and emotional health and well-being. First, as a consequence of allostatic load, stress contributes to disease and disorder. And second, because of effects on specific brain regions, chronic stress takes a second toll by disrupting function in those regions primarily responsible for coping and self-regulation. Implications for future research on resilience and the development of interventions to promote resilience are highlighted.

The balance between optimal levels of emotional arousal and cognitive performance reflects the integration of several dopaminergically and adrenergically regulated neural systems. The amygdalar system is a key region for gating stimulation to cortical regions and the medial amygdala appears to play an especially key role in mediating the fear response. More generally, these arousal regulatory neural systems are key to frustration or stress impact prefrontal cortical function. Further, the threshold for when the level of stress is overwhelming and hence impairs cognitive function reflects minimally genetic and experiential influence. An important interface between Drs. Lewis and Davis's work is how early experience, especially through early parenting, may set the threshold of responsiveness for these arousal regulatory neural systems.