Animal models of fetal renal disease

Fetal models of urinary tract disease have been used for many years and have provided unique and important insights into the pathophysiology of these conditions. This review will summarize the principal model systems used and the current directions of investigation. These models (including rabbit, opossum, sheep and recently swine) have demonstrated that in utero obstruction of the urinary tract alters renal growth, differentiation and produces stereotypical patterns of tissue response, particularly fibrosis. New molecular understanding of these processes has identified specific mechanisms that may be key elements in the development of renal dysfunction due to obstruction. These factors include the renin–angiotensin system (RAS) and its interaction with TGF-β in altering growth regulation and tissue fibrosis. These factors offer the prospect of clinical utility as markers of disease progression as well as pharmacologic therapy. Gene knockout systems have opened a new horizon of molecular models of congenital obstructive uropathy with insights into the role of the RAS in particular. It remains to be defined how closely these knockouts represent the human conditions they resemble. Continued application of fetal models of urinary obstruction, integrating large animal and knockout systems offers promise for improved diagnosis and treatment in these challenging conditions. Copyright © 2001 John Wiley & Sons, Ltd.     

Prenatal assessment of pulmonary vasculature development in fetuses with congenital diaphragmatic hernia: A literature review

Pathophysiological studies have shown that pulmonary vascular development is impaired in fetuses with a congenital diaphragmatic hernia (CDH), leading to a simplified vascular tree and increased vascular resistance. Multiple studies have described prenatal ultrasound parameters for the assessment of the pulmonary vasculature, but none of these parameters are used in daily clinical practice. We provide a comprehensive review of the literature published between January 1990 and February 2022 describing these parameters, and aim to explain the clinical relevance of these parameters from what is known from pathophysiological studies. Prenatal detection of a smaller diameter of the contralateral (i.e. contralateral to the diaphragmatic defect) first branch of the pulmonary artery (PA), higher pulsatility indices (PI), higher peak early diastolic reverse flow values, and a lower vascularization index seem of added value for the prediction of survival and, to a lesser extent, morbidity. Integration within the routine evaluation is complicated by the lack of uniformity of the methods used. To address the main components of the pathophysiological changes, we recommend future prenatal studies in CDH with a focus on PI values, PA diameters and pulmonary vascular branching.     

Engaging an ecovillage and measuring its ecological footprint

As ecovillages present themselves as models of low-carbon living measuring the Ecological Footprint (EF) of an ecovillage serves both to validate that claim and to examine the component features of how the EF is achieved. This article examines the first measurement of the EF of Ireland’s only ecovillage, situated in the village of Cloughjordan in county Tipperary. The objectives here were to measure the EF of the ecovillage at the household scale and then to use the EF to provide meaningful feedback and reflective learning on human carbon intensity to the ecovillage residents. Various methods were applied in this action research to achieve high levels of engagement and potent communication of what could be learnt from the EF. This article places a particular focus on the necessary adaptation of an original EF method, on how it was implemented in the ecovillage, on the results obtained and on how these were communicated to the residents. The bottom-up component EF method samples consumption data at source and in so doing appoints consumption reflection and responsibility in ways the more remote compound method can not. The strategic combination of this specific quality with co-creation method aims to meaningfully engage and motivate a settlement to reduce its carbon intensity. According to the methodology, the ecovillage residents overshoot the fair earth share by 10% needing 1.1 planets to sustain their lifestyles. It is planned that subsequent to this intervention future measurements will show whether the overshoot has reduced.     

Community gardens and sustainable land use planning: A case-study of the Alex Wilson community garden

An analytical account of the history and aspirations of the Alex Wilson Community Garden in Toronto provides an ideal opportunity to examine the connections between two typically distinct enterprises: ecological restoration and community gardening. These are both important contemporary ecological movements, but are rarely combined in a single project that demonstrates the principles of sustainable land use and community planning. The garden is named in memory of Alex Wilson, a landscape designer, community activist and writer who worked and lived in Toronto, Canada. During his life, Wilson established a community garden which was eventually replaced by conventional urban development. After his death in 1993, friends and colleagues decided to honour his memory by establishing a permanent community garden in his name. The Alex Wilson Community Garden opened to the public in June 1998. The case-study explores how the garden reflects Wilson's work by linking community gardening and ecological restoration. These features are unified in Wilson's work as a means of nurturing relationships between people, communities and the landscape—relationships that are social, economic and ecological. In his book,The Culture of Nature: North American landscape from Disney to the Exxon Valdez (1991), Wilson argues that “we must build landscapes that heal and empower, that make intelligible our relations with each other and the natural world”. The Alex Wilson Community Garden illustrates in a practical manner the principles espoused by Wilson through its design, planning and functioning. The case-study reports on the innovative approach to landscape design taken in the garden, which reconstructs the natural and cultural history of southern Ontario, featuring lake-shore, agricultural and woodland sections. The garden has been planted exclusively with native plant species, and is expected to have a positive impact on local biodiversity. The planning process which led up to the design of the garden was participatory in nature, encompassing friends and colleagues of Alex Wilson, local residents and city planning officials, and made use of a number of planning tools not usually applied in an urban setting, including the granting of a conservation easement. The garden also addresses emerging issues associated with globalisation and large cities by providing food production opportunities for local residents, including a low-income housing complex and a nearby drop-in centre. Ecological monitoring and assessment of the naturalised area will be carried out by local residents.     

Kinetic of formation for single carbon dioxide and mixed carbon dioxide and tetrahydrofuran hydrates in water and sodium chloride aqueous solution

A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide–tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time decreases with the increase of the initial carbon dioxide pressure up to 2.96 MPa. Beyond this pressure, the induction time is becoming relatively constant with the increase of initial carbon dioxide pressure indicating that the liquid phase is completely supersaturated with carbon dioxide. Experimental results show that the inclusion of tetrahydrofuran reduces the induction time required for hydrate formation. These observations indicate hydrate nucleation process and onset growth are more readily to occur in the presence of tetrahydrofuran. In contrast, the presence of sodium chloride prolongs the induction time due to clustering of water molecules with the ions and the salting-out effects. It is also shown that the degree of subcooling required for hydrate formation is affected by the presence of tetrahydrofuran and sodium chloride in the hydrate forming system. The presence of tetrahydrofuran in the hydrate system significantly reduces the amount of carbon dioxide uptake. The apparent rate constant, k, for those systems are reported.     

LivestockPlus: Forages,sustainable intensification,and food security in the tropics

The increased use of grain-based feed for livestock during the last two decades has contributed, along with other factors, to a rise in grain prices that has reduced human food security. This circumstance argues for feeding more forages to livestock, particularly in the tropics where many livestock are reared on small farms. Efforts to accomplish this end, referred to as the ‘LivestockPlus’ approach, intensify in sustainable ways the management of grasses, shrubs, trees, and animals. By decoupling the human food and livestock feed systems, these efforts would increase the resilience of the global food system. Effective LivestockPlus approaches take one of two forms: (1) simple improvements such as new forage varieties and animal management practices that spread from farmer to farmer by word of mouth, or (2) complex sets of new practices that integrate forage production more closely into farms’ other agricultural activities and agro-ecologies.