Maternal depressive symptoms and child social preference during the early school years: Mediation by maternal warmth and child emotion regulation

This longitudinal study examined processes that mediate the association between maternal depressive symptoms and peer social preference during the early school years. Three hundred and fifty six kindergarten children (182 boys) and their mothers participated in the study. During kindergarten, mothers reported their level of depressive symptomatology. In first grade, teachers rated children's emotion regulation at school and observers rated the affective quality of mother-child interactions. During second grade, children's social preference was assessed by peer nomination. Results indicated that mothers' level of depressive symptomatology negatively predicted their child's social preference 2 years later, controlling for the family SES and teacher-rated social preference during kindergarten. Among European American families, the association between maternal depressive symptoms and social preference was partially mediated by maternal warmth and the child's emotion regulation. Although the relation between maternal depressive symptoms and children peer preference was stronger among African American families than Europrean American families, its mediation by the maternal warmth and child's emotion regulation was not found in African American families. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

Performance-based building and innovation: Balancing client and industry needs

One reason for the interest in performance-based building is that it is commonly advocated as a powerful way of enhancing innovation performance by articulating building performance outcomes, and by offering relevant procurement actors the discretion to innovate to meet these performance requirements more effectively and/or efficiently. The paper argues that the current approach to performance-based building assumes that relevant actors have the capacity, ability and motivation to innovate from a business perspective. It is proposed that the prevailing conceptualization of PBB is too restrictive and should be broadened explicitly to accommodate the required business logic that must be in place before actors will innovate. The relevant performance-based building and innovation literature is synthesized to support the assertion. The paper concludes with an innovation-focused definition of performance-based building

Mechanisms and Impacts of Earth System Tipping Elements

Tipping elements are components of the Earth system which may respond nonlinearly to anthropogenic climate change by transitioning toward substantially different long-term states upon passing key thresholds or “tipping points.” In some cases, such changes could produce additional greenhouse gas emissions or radiative forcing that could compound global warming. Improved understanding of tipping elements is important for predicting future climate risks and their impacts. Here we review mechanisms, predictions, impacts, and knowledge gaps associated with 10 notable Earth system components proposed to be tipping elements. We evaluate which tipping elements are approaching critical thresholds and whether shifts may manifest rapidly or over longer timescales. Some tipping elements have a higher risk of crossing tipping points under middle-of-the-road emissions pathways and will possibly affect major ecosystems, climate patterns, and/or carbon cycling within the 21st century. However, literature assessing different emissions scenarios indicates a strong potential to reduce impacts associated with many tipping elements through climate change mitigation. The studies synthesized in our review suggest most tipping elements do not possess the potential for abrupt future change within years, and some proposed tipping elements may not exhibit tipping behavior, rather responding more predictably and directly to the magnitude of forcing. Nevertheless, uncertainties remain associated with many tipping elements, highlighting an acute need for further research and modeling to better constrain risks

Interaction of silicon dangling bonds with insulating surfaces

We use first principles density functional theory calculations to study the interaction of a model dangling bond silicon tip with the surfaces of CaF2, Al2O3, TiO2, and MgO. In each case the strongest interaction is with the highest anions in the surface. We show that this is due to the onset of chemical bonding with the surface anions, which can be controlled by an electric field across the system. Combining our results and previous studies on semiconductor surfaces suggests that using dangling bond Si tips can provide immediate identification of surface species in atomically resolved noncontact atomic force microscopy and facilitate selective measurements of short-range interactions with surface sites

The diverse roles of mononuclear phagocytes in prion disease pathogenesis

Transmissible spongiform encephalopathies (TSEs), or prion diseases, are neurological diseases that can be transmitted through a number of different routes. A wide range of mammalian species are affected by the disease. After peripheral exposure, some TSE agents accumulate in lymphoid tissues at an early stage of disease prior to spreading to the nerves and the brain. Much research has focused on identifying the cells and molecules involved in the transmission of TSE agents from the site of exposure to the brain and several crucial cell types have been associated with this process. The identification of the key cells that influence the different stages of disease transmission might identify targets for therapeutic intervention. This review highlights the involvement of mononuclear phagocytes in TSE disease. Current data suggest these cells may exhibit a diverse range of roles in TSE disease from the transport or destruction of TSE agents in lymphoid tissues, to mediators or protectors of neuropathology in the brain

Promiscuity and preferences of metallothioneins: the cell rules

Metalloproteins are essential for many cellular functions, but it has not been clear how they distinguish between the different metals to bind the correct ones. A report in BMC Biology finds that preferences of two metallothionein isoforms for two different cations are due to inherent properties of these usually less discriminating proteins. Here these observations are discussed in the context of the cellular mechanisms that regulate metal binding to proteins

All clinically-relevant blood components transmit prion disease following a single blood transfusion: a sheep model of vCJD

Variant CJD (vCJD) is an incurable, infectious human disease, likely arising from the consumption of BSE-contaminated meat products. Whilst the epidemic appears to be waning, there is much concern that vCJD infection may be perpetuated in humans by the transfusion of contaminated blood products. Since 2004, several cases of transfusion-associated vCJD transmission have been reported and linked to blood collected from pre-clinically affected donors. Using an animal model in which the disease manifested resembles that of humans affected with vCJD, we examined which blood components used in human medicine are likely to pose the greatest risk of transmitting vCJD via transfusion. We collected two full units of blood from BSE-infected donor animals during the pre-clinical phase of infection. Using methods employed by transfusion services we prepared red cell concentrates, plasma and platelets units (including leucoreduced equivalents). Following transfusion, we showed that all components contain sufficient levels of infectivity to cause disease following only a single transfusion and also that leucoreduction did not prevent disease transmission. These data suggest that all blood components are vectors for prion disease transmission, and highlight the importance of multiple control measures to minimise the risk of human to human transmission of vCJD by blood transfusion

Generalized approach to translating exercise tests and prescribing exercise

Although there is evidence supporting the benefit of regular exercise, and recommendations about exercise and physical activity, the process of individually prescribing exercise following exercise testing is more difficult. Guidelines like % heart rate (HR) reserve (HRR) require an anchoring maximal test and do not always provide a homogenous training experience. When prescribing HR on the basis of % HRR, rating of perceived exertion or Talk Test, cardiovascular/perceptual drift during sustained exercise makes prescription of the actual workload difficult. To overcome this issue, we have demonstrated a strategy for "translating" exercise test responses to steady state exercise training on the basis of % HRR or the Talk Test that appeared adequate for individuals ranging from cardiac patients to athletes. However, these methods depended on the nature of the exercise test details. In this viewpoint, we combine these data with workload expressed as Metabolic Equivalent Task (METs). We demonstrate that there is a regular stepdown between the METs during training to achieve the same degree of homeostatic disturbance during testing. The relationship was linear, was highly-correlated (r = 0.89), and averaged 71.8% (Training METs/Test METs). We conclude that it appears possible to generate a generalized approach to correctly translate exercise test responses to exercise training

Pathogenesis of bovine spongiform encephalopathy in sheep

The pathogenesis of bovine spongiform encephalopathy (BSE) in sheep was studied by immunohistochemical detection of scrapie-associated prion protein (PrPSc) in the gastrointestinal, lymphoid and neural tissues following oral inoculation with BSE brain homogenate. First accumulation of PrPSc was detected after 6 months in the tonsil and the ileal Peyer’s patches. At 9 months postinfection, PrPSc accumulation involved all gut-associated lymphoid tissues and lymph nodes as well as the spleen. At this time point, PrPSc accumulation in the peripheral neural tissues was first seen in the enteric nervous system of the caudal jejunum and ileum and in the coeliac-mesenteric ganglion. In the central nervous system, PrPSc was first detected in the dorsal motor nucleus of the nervus Vagus in the medulla oblongata and in the intermediolateral column in the spinal cord segments T7–L1. At subsequent time points, PrPSc was seen to spread within the lymphoid system to also involve all non-gut-associated lymphoid tissues. In the enteric nervous system, further spread of PrPSc involved the neural plexi along the entire gastrointestinal tract and in the CNS the complete neuraxis. These findings indicate a spread of the BSE agent in sheep from the enteric nervous system through parasympathetic and sympathetic nerves to the medulla oblongata and the spinal cord