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The autoclaving, pasteurization, and freezing of bone grafts to remove bacteria and viruses, and for preservation, respectively, is considered to alter biological properties during graft consolidation. Fresh bone grafts release paracrine-like signals that are considered to support tissue regeneration. However, the impact of the autoclaving, pasteurization, and freezing of bone grafts on paracrine signals remains unknown. Therefore, conditioned medium was prepared from porcine cortical bone chips that had undergone thermal processing. The biological properties of the bone-conditioned medium were assessed by examining the changes in expression of target genes in oral fibroblasts. The data showed that conditioned medium obtained from bone chips that had undergone pasteurization and freezing changed the expression of adrenomedullin, pentraxin 3, BTB/POZ domain-containing protein 11, interleukin 11, NADPH oxidase 4, and proteoglycan 4 by at least five-fold in oral fibroblasts. Bone-conditioned medium obtained from autoclaved bone chips, however, failed to change the expression of the respective genes. Also, when bone-conditioned medium was prepared from fresh bone chips, autoclaving blocked the capacity of bone-conditioned medium to modulate gene expression. These in vitro results suggest that pasteurization and freezing of bone grafts preserve the release of biologically active paracrine signals, but autoclaving does not. [ABSTRACT FROM AUTHOR]

In this study a close to reality one component (1K) structural epoxy adhesive is introduced. The physical properties have been investigated by means of gravimetric water uptake, bulk tensile tests, and lap shear tests. The influence of two different types of hollow glass microspheres (HGM) on the ageing behaviour has been observed via accelerated ageing tests followed by lap shear tests of galvanized steel. Results show that the formulation described outperforms very brittle and basic systems consisting of bisphenol A diglycidyl ether (DGEBA) and dicyandiamide (DICY) in terms of ductility. The addition of HGM resulted in higher water absorption suggesting that water gathers as a liquid in the HGM. Further, the addition of HGM led to an increase of the cohesion failure percentage on unaged lap shear specimens without significantly influencing the tensile shear strength and the addition of the bigger HGM observed led to a change in fracture mechanism from substrate-near cohesion failure to cohesion failure. The results of this study on the long-term durability of bonded steel joints indicate that the addition of HGM into the adhesive system has no significant effect on the ageing behaviour in two of three corrosion tests. It can be concluded that the incorporation of HGM is a possible solution not only reducing the amount of chemicals required for automotive adhesive production, but also promoting lightweight construction because of the decreased density of the adhesive system. • A novel, near to realism structural epoxy adhesive for scientific purposes. • Gravimetric water uptake in structural epoxy adhesive. • Ageing resistance of adhesively bonded steel sheets. • Addition of hollow glass microspheres changes fracture mechanism. [ABSTRACT FROM AUTHOR]

In the current paper, we first introduce the research themes of the attention, behaviour and sleep (ABS) laboratory, namely, sleep and ADHD, sleep and obesity, and sleep and academic performance. We then focus in on the topic to be reviewed in the current paper – the association between sleep restriction and neurobehavioral functioning (NBF) in typically developing children. We review the research thus far conducted by the ABS lab specific to this topic and posit the unique methodological contributions of the ABS lab (e.g. home-based assessment of sleep architecture and patterns, extensive phenotyping, etc.) in terms of advancing this research area. In the second section of the paper, we review 13 studies investigating the causal association between experimental sleep restriction and NBF in normally developing pediatric populations. Eight of the 13 studies found that sleep restriction causes impairments in neurobehavioural functioning. However, given the inconsistency in outcome measures, experimental protocols and statistical power, the studies reviewed herein are difficult to interpret. Strategies used by the ABS including implementing home assessments of sleep, restricting sleep relative to the participants’ typical sleep schedules, blinding raters who assess NBF, and using valid and reliable NBF assessments are an attempt to address the gaps in this research area and clarify the causal relationship between sleep restriction and NBF in typically developing children and adolescents. [ABSTRACT FROM AUTHOR]

Soil management techniques, such as mulching, are used to enhance soil organic carbon sequestration. However, we demonstrate that the potential of crop residue mulching to increase soil organic carbon (SOC) sequestration varies by cropping system and soil type in Austrian agricultural soils. Effects of mulch (as harvested crop residues applied at 1.0 t C ha −1 ) on soil and microbial carbon (C) and nitrogen (N) and soil δ 13 C were measured in an Austrian Cambisol field experiment with sole maize or vetch or vetch-maize rotation cropping systems after five years with or without mulching to elucidate how SOC is affected. The direct role of mulch on SOC in different soil types was also investigated in a similar greenhouse mesocosm study with controlled moisture using the same Cambisols and an Austrian agricultural Chernozem. Only sole maize cropping in the field experiment resulted in higher SOC with mulching and when legumes were included in a legume-maize rotation SOC did not improve. Mulching in the field experiment only resulted in higher SOC in the top 0–5 cm of soils with sole maize cropping (by 22%) compared to soils without mulch. Although mulch did not increase SOC in vetch-maize rotation, the δ 13 C of SOC was less negative with mulch indicating larger C contribution from maize than vetch mulch. After four years of annual soybean-maize rotation in the mesocosm experiment, no significant differences in SOC were observed in Cambisols with or without mulch. Again, δ 13 C of both soil types was less negative with mulching indicating a larger C contribution from maize than soybean mulch. No relationships between microbial biomass C and N and SOC were observed in either experiment and only soil N concentration was positively correlated with SOC. Together these studies indicate that maize can increase SOC when crop residues are applied in Austrian Cambisols but that inclusion of legume production and legume mulch in rotation can mute these benefits. [ABSTRACT FROM AUTHOR]