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The extracellular matrix plays a critical role in modulating cell behaviour in the developing and adult central nervous system influencing neural cell morphology, function and growth. Neurons and astrocytes, play vital roles in neural signalling and support respectively and respond to cues from the surrounding matrix environment. However, a better understanding of the impact of specific individual extracellular matrix proteins on both neurons and astrocytes is critical for advancing the development of matrix‐based scaffolds for neural repair applications. This study aimed to provide an in‐depth analysis of how different commonly used extracellular matrix proteins— laminin‐1, Fn, collagen IV, and collagen I—affect the morphology and growth of trophic induced pluripotent stem cell (iPSC)‐derived astrocyte progenitors and mouse motor neuron‐like cells. Following a 7‐day culture period, morphological assessments revealed that laminin‐1, fibronectin, and collagen‐IV, but not collagen I, promoted increased process extension and a stellate morphology in astrocytes, with collagen‐IV yielding the greatest increases. Subsequent analysis of neurons grown on the different extracellular matrix proteins revealed a similar pattern with laminin‐1, fibronectin, and collagen‐IV supporting robust neurite outgrowth. fibronectin promoted the greatest increase in neurite extension, while collagen‐I did not enhance neurite growth compared to poly‐L‐lysine controls. Super‐resolution microscopy highlighted extracellular matrix‐specific nanoscale changes in cytoskeletal organization, with distinct patterns of actin filament distribution where the three basement membrane‐associated proteins (laminin‐1, fibronectin, and collagen‐IV) promoted the extension of fine cellular processes. Overall, this study demonstrates the potent effect of laminin‐1, fibronectin and collagen‐IV to promote both iPSC‐derived astrocyte progenitor and neuronal growth, yielding detailed insights into the effect of extracellular matrix proteins on neural cell morphology at both the whole cell and nanoscale levels. The ability of laminin‐1, collagen‐IV and fibronectin to elicit strong growth‐promoting effects highlight their suitability as optimal extracellular matrix proteins to incorporate into neurotrophic biomaterial scaffolds for the delivery of cell cargoes for neural repair. [ABSTRACT FROM AUTHOR]

A comparison was made between four methods of generating roundwood production forecasts for private sector forests in Ireland which used varying levels of inventory data as inputs into the production Model. Two methods were based on stand variables: the Irish Dynamic Yield Model (IDYM) method and the General Yield Class (GYC) method. The other two methods were based on site variables used to derive predictions of productivity from climate and map-based data and include a local prediction (LPYC) and a national prediction of yield class (NPYC), the latter the same as that used in the All Ireland Roundwood Production Forecast 2016-2035 (Phillips et al. 2016). To determine the reliability of predictions for an individual stand, field measurements of yield class (GYC) were compared with the predictions of yield class derived using the NPYC and LPYC methods for 52 privately-owned stands of Sitka spruce in the north-west of Ireland. The prediction of yield class using the NPYC method had a low probability of agreement with GYC, with a large bias to under-predict yield class. The LPYC method had a higher probability of agreement and lower bias indicating a better assessment of local productivity. To assess the impact of the various productivity estimates on roundwood production forecasts, separate roundwood forecasts for the period 2016- 2035 were generated. The forecast produced using the NPYC method was used as a baseline for comparison purposes. As expected, the under-prediction of yield class using the NPYC method produced the lowest volume production estimate (318,454 m3) for the forecast period. Both the GYC and LPYC methods resulted in a significant increase in estimated volume production of between 25% and 29% over the baseline. The IDYM method provided the highest estimate of volume production (432,000 m3) for the forecast period, an increase of 35% over the baseline. The increased output predicted using the IDYM method is explained by the inclusion of stocking and basal area data, which more accurately reflected the increased growing stock of private forests than yield data derived using Forestry Commission yield models based on prescribed management. The increases in productivity associated with the use of LPYC, GYC and IDYM methods had the effect of producing shorter rotations and resulted in an increase in the area clearfelled and associated volume production. Perhaps more importantly, the timing of volume production was affected by using more accurate methods to assess productivity (i.e. LPYC, GYC, IDYM), owing to a higher yield-age profile of stands compared to those assessed using the NPYC predictions. The findings point to a possible under-estimation of the productivity for private stands in the All Ireland Roundwood Production Forecast and have implications for the timing of the forecasted volume which could be brought forward by 5 to 6 years. In the absence of field or aerial laser measurement of height and age, the use of the LPYC method is recommended for future private sector roundwood producion forecasts. [ABSTRACT FROM AUTHOR]

Models of disability assume that impairments have only a limiting effect on technology usage. Drawing upon the results of a year-long participant observation study of the use of camcorders by six severely intellectually disabled adults, we argue that intellectual disability (ID) affects the domestication of technology in a more complex and interwoven fashion. The observed group of ID adults attended a weekly 2-h session, organised by a local day centre, in which they would make videos at local locations. There were two main aspects of appropriation in this context. One is the role of the support worker (SW) in mediating many of their interactions due to accessibility problems with the camcorder. While these interventions by the SW allowed them to use the camcorder, they also slowed their interactions with it making them less direct. SW also guided and constrained their early encounters with the camcorders, strongly influencing the environment of appropriation. The second aspect is the way the group transformed the camcorder into two tools during the course of the study: an ‘artistic’ tool for visual exploration, and a ‘social’ tool that participated in the group’s social activities. These appropriations are very different to anything reported in the literature on mainstream camcorder use. While technologists typically model disability as a set of functional limitations, we would argue for broader models that consider the wider social and support aspects of ID, recognising the different ways in which they may choose to make a technology mundane for them. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spinal cord injury damages axons, causing loss of motor and sensory function. • Promoting and guiding axonal regrowth is essential for functional recovery. • 3D-printed, electroconductive scaffolds with tuneable geometries were developed. • Scaffolds were functionalised with aligned, neurotrophic extracellular matrix. • Electrostimulation via scaffolds significantly increased outgrowth from neurons. Spinal cord injury (SCI) is a devastating neurotrauma, affecting 250,000 to 500,000 people annually, and typically results in paralysis. Electrostimulation can promote neuronal growth, but the formation of a lesion cavity post-SCI inhibits regrowth, limiting its efficacy. Bridging the lesion with a structured, electroactive substrate to direct electrostimulation to growing neurites could support and drive neuronal regrowth through the lesion to enable functional recovery but to date, no such platform exists. This study describes the development of an electroconductive (15 ± 5 S/m), 3D-printed scaffold, comprising a polypyrrole/polycaprolactone framework filled with biomimetic & neurotrophic extracellular matrix. 3D printing allowed inclusion of channels in the scaffold designed to mimic the size of human corticospinal tracts to direct electrostimulation to growing neurons. Scaffolds exhibited excellent biocompatibility with both neurons and human primary astrocytes and maintained electrical and biofunctionality when scaled to match the size of human corticospinal tracts. When neurons were cultured for 7 days on the scaffolds under continuous electrostimulation (200 mV/mm, 12 Hz), significantly longer neurites were observed on electrically stimulated electroconductive scaffolds. These results demonstrate that electrostimulation applied via an anatomically-mimetic, 3D-printed electroconductive scaffold drives neurite outgrowth and represents a promising approach for treatment of spinal cord injury. [ABSTRACT FROM AUTHOR]