Double jeopardy: the potential for problems when bats interact with breathable roofing membranes in the United Kingdom

In order to reduce environmental impacts and achieve sustainability, it is important to balance the interactions between the built and natural environment. The construction industry is becoming more aware of ecological concerns and the importance that biodiversity and maintenance ecosystem services has for sustainability. Bats constitute an important component of urban biodiversity and several species in the UK are highly dependent on buildings, making them particularly vulnerable to anthropogenic and environmental changes. Many buildings suitable for use as bat roosts often require re-roofing as they age and traditional bituminous roofing felts are frequently being replaced with breathable roofing membranes (BRMs). In the UK new building regulations and modern materials may substantially reduce the viability of existing roosts, yet at thesame time building regulations require that materials be fit for purpose. Reports suggest that both bats and BRMs may experience problems when the two interact. Such information makes it important to understand how house dwelling bats and BRMs may be affected. This paper considers the possible ways in which bats and BRMs may interact, how this could affect existing bat roosts within buildings and the implications for BRM service life predictions and warranties. Keywords –Breathable Roofing Membranes, Bats in Buildings, Material Deterioration, Sustainability, Conservation, Biodiversi

The technique of bladder implantation: further results and an assessment.

JuLL (1951) suggested that the surgical introduction of a pellet containing a test chemical into the lumen of the mouse bladder might be useful for routine testing for carcinogenic activity. The method, it was thought, would possess the following advantages: (i) the chemical would be slowly eluted from the pellet and would therefore remain in contact with the bladder epithelium for a prolonged period; (ii) the metabolic processes of the liver, etc., would be by-passed, and (iii) the bladder would function under approximately normal conditions. Bladder implantation has been used successfully in Leeds (Bonser, Clayso

Failure of retrograde cerebral perfusion to attenuate metabolic changes associated with hypothermic circulatory arrest

AbstractObjectives: Although retrograde cerebral perfusion has become a popular adjunctive technique and may improve cerebral ischemic tolerance during hypothermic circulatory arrest, direct cerebral metabolic benefit has yet to be demonstrated in human subjects. We investigated the post-arrest metabolic phenomena with and without retrograde cerebral perfusion in patients. Methods: In a prospective randomized trial, 42 patients undergoing aortic surgery requiring hypothermic circulatory arrest were allocated to receive hypothermic circulatory arrest alone (n = 21) or hypothermic circulatory arrest with additional retrograde cerebral perfusion (n = 21). Circulatory arrest was commenced at 15°C, and retrograde perfusion was instituted through the superior vena cava at a maximum jugular bulb pressure of 25 mm Hg. Transcranial, paired, repeated samples of the arterial and jugular bulb blood were analyzed for oxygen and glucose. Velocity in the right middle cerebral artery was also measured simultaneously. Results: There were 3 (7.1%) deaths and 3 (7.1%) episodes of neurologic deficit. Mean bypass and circulatory arrest duration (in minutes) were similar between groups (P = .4 and .14). The mean retrograde perfusion duration was 23 minutes. Post-arrest nasopharyngeal temperature was similar (15.3°C vs 15.3°C). Retrograde perfusion did not affect post-arrest oxygen extraction, glucose extraction, or jugular bulb Po2. There was no immediate lactate release immediately after hypothermic circulatory arrest. Conclusions: Retrograde cerebral perfusion did not influence immediate post-arrest nasopharyngeal temperature or cerebral metabolic recovery. The low jugular bulb Po2 suggests equivalent ischemia. These findings cast doubt on the effectiveness of retrograde cerebral perfusion as a metabolic adjunct to hypothermic circulatory arrest.J Thorac Cardiovasc Surg. 2002;123:943-50

Plant size and neighbourhood characteristics influence survival and growth in a restored ex‐agricultural ecosystem

Restoring woody vegetation on degraded agricultural land is a widespread and common ecological restoration practice. However, highly variable plant survival and growth limit outcomes for many projects. Inconsistent reporting and monitoring of projects mean that an assessment of the relative importance of community-assembly processes is limited, particularly over longer timescales. We use 7 years of monitoring data of nearly 2000 native trees and shrubs in a restoration project on ex-agricultural land in south-western Australia to test the potential effects of facilitation or competition from neighbouring plants, as well as look for patterns in their interaction with the attributes of individuals and species traits. Overall, plant size was the strongest single predictor of survival and incremental growth. Individual plants in neighbourhoods with higher inter-generic basal area were more likely to survive, with this effect strongest in smaller individuals. When plants were larger, they were less likely to grow when in neighbourhoods with high intra-generic basal area. Taller-growing plants (higher species maximum height) were more likely to survive when individuals were small (basal area of 1–10 cm2), compared with shorter growing plants. Growth was also more likely in taller-growing plants, and this relationship increased with the size of the individual. Recruitment was very low, with just 148 new recruits recorded across the 42 plots over 7 years. Maximizing the growth of plants in restorations in the early stages may promote survival and growth in the longer term. We also demonstrate that increased levels of inter-generic neighbouring plants may improve individual plant survival in the restoration of ex-agricultural land. As a result, we suggest tailoring direct-seeding methods to minimize clustering of congeneric individuals. We also highlight the need to find means of promoting recruitment for the long-term sustainability of restoration efforts