There are widespread concerns that current trends in resource-use are unsustainable, but possibilities of overshoot/collapse remain controversial. Collapses have occurred frequently in history, often followed by centuries of economic, intellectual, and population decline. Many different natural and social phenomena have been invoked to explain specific collapses, but a general explanation remai...

Abstract: A finite element model is verified accurate enough to simulate the static test of one reinforced-concrete frame with specially shaped columns subjected to the loss of a ground corner column. As the frame sustained loads primarily depending on the beam resisting mechanism in the test, four related parameters, namely the height of beam section, rebar ratio of beam, rebar ratio of slab a...

We have studied the relationship between emphysema and airways collapse, and response to corticosteroids in patients with chronic airflow obstruction. One hundred and seven patients completed a placebo-controlled trial comparing 2 wks treatment with oral prednisolone 40 mg.day-1 to inhaled beclomethasone dipropionate 500 micrograms t.d.s. Response to corticosteroids was defined on the basis of ...