Control of porosity and pore size of metal reinforced carbon nanotube membranes

Membranes are crucial in modern industry and both new technologies and materials need to be designed to achieve higher selectivity and performance. Exotic materials such as nanoparticles offer promising perspectives, and combining both their very high specific surface area and the possibility to incorporate them into macrostructures have already shown to substantially increase the membrane performance. In this paper we report on the fabrication and engineering of metal-reinforced carbon nanotube (CNT) Bucky-Paper (BP) composites with tuneable porosity and surface pore size. A BP is an entangled mesh non-woven like structure of nanotubes. Pure CNT BPs present both very high porosity (>90%) and specific surface area (>400 m2/g). Furthermore, their pore size is generally between 20–50 nm making them promising candidates for various membrane and separation applications. Both electro-plating and electroless plating techniques were used to plate different series of BPs and offered various degrees of success. Here we will report mainly on electroless plated gold/CNT composites. The benefit of this method resides in the versatility of the plating and the opportunity to tune both average pore size and porosity of the structure with a high degree of reproducibility. The CNT BPs were first oxidized by short UV/O3 treatment, followed by successive immersion in different plating solutions. The morphology and properties of these samples has been investigated and their performance in air permeation and gas adsorption will be reported.

The timing of Rapid-Response Team activations: a multicentre international study

Background:
Most studies of Rapid-Response Teams (RRTs) assess their effect on outcomes of all hospitalised patients. Little information exists on RRT activation patterns or why RRT calls are needed. Triage error may necessitate RRT review of ward patients shortly after hospital admission. RRT diurnal activation rates may reflect the likely frequency of caregiver visits.

Objectives:
To study the timing of RRT calls in relation to time of day and day of week, and their frequency and outcomes in relation to days after hospital admission.

Methods:
We prospectively studied RRT calls over 1 month in seven hospitals during 2009, collecting data on patient age, sex, admitting unit, admission source, limitations of medical therapy (LOMTs), and admission and discharge dates. We assessed the timing of RRT calls in relation to hospital admission and circadian variation; and differences in characteristics and outcomes of calls occurring early (Days 0 and 1) versus late (after Day 7) after hospital admission.

Results:
There were 652 RRT calls for 518 patients. Calls were more likely on Mondays (P=0.018) and during work hours (P<0.0001) but less likely on weekends (P=0.003) or overnight (P<0.001). There were 177 early calls (27.1%) and 198 late calls (30.4%). Early calls involved younger patients (median ages, 67.5 years [early calls] v 73 years [late calls]; P= 0.01), fewer LOMTs (P=0.029), and lower in hospital mortality (12.8% [early calls] v 32.3% [late calls]; P<0.0001). The mortality difference remained in patients without LOMTs (5.6% [early calls] v 19.6% [late calls]; P=0.003).

Conclusions:
About one-quarter of RRT calls occurred shortly after hospital admission, and were more common when caregivers were around. Early calls may partially reflect suboptimal triage, though the associated mortality appeared low. Late calls may reflect suboptimal end-of-life care planning, and the associated mortality was high. There is a need to further assess the epidemiology of RRT calls at different phases of the hospital stay.

The poetic presentation of philosophy:Leo Strauss on Plato’s “symposium”

This essay undertakes a close analysis of Leo Strauss’s remarkable but undertreated Leo Strauss on Plato’s “Symposium,” reading it as opening a privileged purview of his own (and his students’) wider understandings of philosophy, poetry, and politics. The essay begins by drawing out Strauss’s three framing justifications for his manner of reading the Symposium as a document in the “ancient quarrel” of philosophy and poetry concerning which of the two should rightly shape the culture and ethical ideals of the Greeks (part 1). Then, following the course of Plato’s Symposium, the essay ascends through Strauss’s readings of the first five speeches in Plato’s dialogue (part 2) toward the highlight of Strauss’s reading, namely, his three remarkable sessions on Socrates’s speech. Part 3 analyses Strauss’s reading of this speech up to its climax, which Strauss argues involves the philosophical “demotion of poetry”: a criticism of poets as motivated by the Eros of fame and of tragic poetry as at its best creating captivating images of gods and heroes which reflect their creators’ self-love and patriotic love of “one’s own,”as against any transpolitical truth. Part 4 then looks at Strauss’s unusual reading of the culmination of Socrates’s great speech (Diotima on the “higher mysteries”) alongside Alkibiades’s speech in the Symposium as representing Plato’s “poetic presentation of philosophy.” The essay becomes more critical as it proceeds. Strauss’s reading of the Symposium, like his reading of the Republic, is remarkable for its own “demotion of metaphysics” in Plato, and in my concluding remarks, I will question this status, or disappearance, of metaphysics in Strauss’s Platonism and whether this disappearance compromises Strauss' ability to differentiate philosophy as he sees it from poetry.

Aristotle and the authoritativeness of politikē

This paper explores the normative implications of Aristotle's concept of politikē and demonstrates its relevance to contemporary debates on legitimate political authority. Section one of the paper provides historical and interpretative background on Aristotle's conception of politikē. The second section examines the central normative role that the common good plays in Aristotle's account of politikē and claims that its capacity to play this role points in the direction of a less exclusionary politics than is suggested by Book 1 of the Politics. Finally, in the third section, with reference to work by Andres Rosler and David Estlund, I consider what Aristotle's account can tell us about contemporary debates on the relationship between political authority, legitimacy and expertise.