Arcology and arcosanti: towards a sustainable built environment

Does theory arcology and practice (the Arcosanti Project) respond to the overlapping challenges in the movement toward more sustainable built environments

The urban environment : agendas and problems

The United Nations estimate that by 2025 there will be around 5 billion people living in urban areas, more than the total world population 20 years ago. Currently, the developed nations are the most urbanised with, on average around three-quarters of their population living in cities, but this is changing. Increased levels of economic growth, of migration, of population expansion and, in some cases, of unprecedented industrial growth, mean that Asia and Africa will be the regions most radically affected by urban development over the next twenty years. Increasing debate on issues of urban sustainability has led to the consolidation of environmental agendas and the definition of a specific body of problems and policy issues on two levels. The first involves green agenda problems occupying the concerns of many in the developed nations such as global warming, ozone-layer depletion, loss of bio-diversity, deforestation, and the exhaustion of non-renewable resources. For the developing world, however, these global environmental problems are less immediate than the need to resolve acute problems relating to poverty and the so-called brown agenda problems of air and water pollution, inadequate waste management, the lack of basic services and green areas, declining infrastructure, and poor housing conditions, as well as issues of health, crime, violence, and social exclusion. It is now a commonly held belief that the green agenda cannot be addressed until the urgent problems of urban social deprivation and inequalities are resolved. This paper reviews the scale and character of contemporary urbanisation and the rapid growth of cities, particularly within the developing nations, and examines associated implications with respect to the physical arrangement of cities, their resource consumption and their environmental impact

Towards a framework for university-wide postgraduate programmes in sustainability

The role of Higher Education Institutions in addressing social, environmental, and economic challenges and opportunities in today's world is immense, complex, and vital (GUNI, 2008). Traditionally responses to sustainable development (SD) have been concentrated within specific subjects, however there has been a gradual penetration of sustainability issues into a wide spectrum of disciplines (HEA, February 2009. The definition and priorities of SD are complex and multi-layered and the challenges presented, being inherently holistic, require equal responses from all disciplines. This requires the development of a framework for University-wide, cross disciplinary teaching. The University of Strathclyde has been ranked first in the Engineering Education for Sustainable Development (ESD) Observatory Report 2008. Building on this success, work is underway to develop a university-wide, interdisciplinary Strathclyde Masters programme in Sustainability (SMS, aimed at articulating a framework for integrating flagship postgraduate courses & classes, sustainability literacy & skills training workshops. This paper summarises the theories of sustainability and its inherent interdisciplinary nature by examining current thinking in ESD. This has highlighted the need to review the current curriculum, identifying current interdisciplinary provision aligned with ESD, and implement a multistakeholder consultation process. The paper describes how these theories might be put into practice, detailing the conclusions drawn from the initial consultation process involving external organisations, students, academic staff and the university's professional services. In addition, a model 'Sustainability Map' is presented offering an overview of postgraduate provision of ESD within the institution as a whole, alongside details of the courses offered and contributing departments. The outcome of the multistakeholder consultation process, in conjunction with the 'Sustainability Map', will help inform future consultation focusing on structural refinement and the academic content of the interdisciplinary programme

Optimization of an oxide dispersion strengthened Ni-Cr-Al alloy for gas turbine engine vanes

The investigation was carried out to determine the optimum alloy within the Ni-16Cr-Al-Y2O3 system for use as a vane material in advanced aircraft gas turbine engines. Six alloys containing nominally 4%, 5% and 6% Al with Y2O3 levels of 0.8% and 1.2% were prepared by mechanical attrition. Six small-scale, rectangular extrusions were produced from each powder lot for property evaluation. The approximate temperatures for incipient melting were found to be 1658 K (2525 F), 1644 K (2500 F) and 1630 K (2475 F) for the 4%, 5% and 6% aluminum levels, respectively. With the exception of longitudinal crystallographic texture, the eight extrusions selected for extensive evaluation either exceeded or were close to mechanical property goals. Major differences between the alloys became apparent during dynamic oxidation testing, and in particular during the 1366 K (2000 F)/500 hour Mach 1 tests carried out by NASA-Lewis. An aluminum level of 4.75% was subsequently judged to be optimum based on considerations of dynamic oxidation resistance, susceptibility to thermal fatigue cracking and melting point

Lessons from the urban laboratory at Arcosanti in Arizona

The Trouble with Autocratic Architecture: A critical and cocreative look at Paolo Soleri's Arcosanti Project. Doctress Neutop

Extractives From Grand Fir [Abies Grandis (DOUGL.) LINDL.] Bark

The neutral fraction of the petroleum-ether-soluble bark extract contains a homologous series of normal alkanes (C19 to C42), free β-sitosterol, behenyl and lignoceryl alcohols, esters of these three compounds with arachidic, behenic, and lignoceric acids, and a major fraction comprising a mixture of behenyl and lignoceryl ferulates. The triterpene lactones cyclograndisolide and epicyclograndisolide are minor components

Towards an engineering theory of evolution

Effective biological engineering requires the acknowledgement of evolution and its consideration during the design process. In this perspective, the authors present the concept of the evotype to reason about and shape the evolutionary potential of natural and engineered biosystems

Adaptive statistical iterative reconstruction improves image quality without affecting perfusion CT quantitation in primary colorectal cancer

Objectives: To determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR) on perfusion CT (pCT) parameter quantitation and image quality in primary colorectal cancer. Methods: Prospective observational study. Following institutional review board approval and informed consent, 32 patients with colorectal adenocarcinoma underwent pCT (100 kV, 150 mA, 120 s acquisition, axial mode). Tumour regional blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) were determined using identical regions-of-interests for ASIR percentages of 0%, 20%, 40%, 60%, 80% and 100%. Image noise, contrast-to-noise ratio (CNR) and pCT parameters were assessed across ASIR percentages. Coefficients of variation (CV), repeated measures analysis of variance (rANOVA) and Spearmanâ rank order correlation were performed with statistical significance at 5%. Results: With increasing ASIR percentages, image noise decreased by 33% while CNR increased by 61%; peak tumour CNR was greater than 1.5 with 60% ASIR and above. Mean BF, BV, MTT and PS differed by less than 1.8%, 2.9%, 2.5% and 2.6% across ASIR percentages. CV were 4.9%, 4.2%, 3.3% and 7.9%; rANOVA P values: 0.85, 0.62, 0.02 and 0.81 respectively. Conclusions: ASIR improves image noise and CNR without altering pCT parameters substantially. Keywords: Perfusion imaging, Multidetector computed tomography, Colorectal neoplasms, Computer-assisted image processing, Radiation dosag

Circadian rhythmicity in emerging mood disorders: state or trait marker?

Background: Circadian rhythm disturbances overlap with the symptoms of mood episodes and may trigger or prolong mood symptoms. There is limited research on the role of circadian disturbances in mood disorders in young people and/or first episode cases of unipolar and bipolar disorders. Methods: Actigraphy was undertaken for about 14 days in 63 post-pubertal individuals aged 13–25 years with a recent onset of a mood disorder meeting recognised diagnostic criteria. We examined associations between three easily interpretable markers of circadian rhythm activity (amplitude, acrophase and rhythmicity index) and demography and clinical characteristics. Then, circadian markers were compared between diagnostic groups, controlling for potential confounders. Results: Longer duration of illness was correlated with reduced circadian rhythmicity and lower levels of activity over 24 h. A delay in the timing of maximum activity was associated with the level of manic but not depressive symptoms. The circadian rhythmicity index differentiated unipolar from bipolar cases, and in bipolar but not unipolar disorder, the rhythmicity was less robust in those with more severe manic or depressive symptoms. Conclusions: Less robust circadian rhythmicity, especially associated with increasing symptom severity, may represent a more specific or a trait marker of young people with mood disorders who are at higher risk of a bipolar course of illness