Unit operations for gas-liquid mass transfer in reduced gravity environments

Basic scaling rules are derived for converting Earth-based designs of mass transfer equipment into designs for a reduced gravity environment. Three types of gas-liquid mass transfer operations are considered: bubble columns, spray towers, and packed columns. Application of the scaling rules reveals that the height of a bubble column in lunar- and Mars-based operations would be lower than terrestrial designs by factors of 0.64 and 0.79 respectively. The reduced gravity columns would have greater cross-sectional areas, however, by factors of 2.4 and 1.6 for lunar and Martian settings. Similar results were obtained for spray towers. In contract, packed column height was found to be nearly independent of gravity

Determination of Flaw Growth Characteristics of Ti-6Al-4V Sheet in the Solution-Treated and Aged Condition

The specific experimental investigation undertaken was designed to answer these questions on Ti-6Al-4V in the solution treated and aged condition. The defect growth and fracture characteristics were studied in parent (unwelded) and welded sheet material. The results of the study indicate that cryogenic proof testing will screen smaller size defects than proof testing at ambient conditions. However some unusual crack growth behavior during the proof test simulation suggests that some further study be made of stress and time duration effects

An international survey of mature students' uses of mobile devices in life and learning

The paper presents research concerned with learner-driven innovative practice with mobile technologies and the interface between formal and informal learning. We build on our previous work investigating student use of personal devices for learning, work, social interaction and entertainment. A recent phase of the research included an international survey focusing on students registered on selected Masters and doctoral programmes in the UK, Sweden, Portugal, Hong Kong and Australia. The research gives an account of everyday uses and more unusual deployments of personal technologies by students from departments of education and technology. It illuminates learner choices and preferences, attitudes towards work–life boundaries, evolving social and cultural practices, and the impacts of technological change

The Effect of Porosity Density and Configuration in Composite Materials on the Ultrasonic Waveform

Current practice is to accept or reject composite parts based upon ultrasonic C-scan results. Normally, this is based only on ultrasonic attenuation data. However, attenuation data alone does not account for variations in porosity distribution or type, and ignores the fact that other variables can influence attenuation besides porosity. This work was directed at determining additional parameters which can be used to define the defect structure in a composite

Turning the Tempest for God’s Forgotten: Psalm 42 as Synecdochic Lead of the Elohistic Psalter

This dissertation’s thesis states Ps 42 is the synecdochic lead of the Elohistic Psalter, arguing for a particular type of literary relationship between Ps 42 and this collection (Pss 42-83). As synecdoche, Ps 42 introduces and represents, in microcosm, the themes, imagery, language, and actuational potential of the collection. The lead psalm becomes a lens that affects what aspects and commonalities come to light in the following psalms. This is not merely an intertextual study, however. This study is situated within psalms studies and the long reach of Gerald Wilson’s work and the Shape and Shaping approach to the Psalter. Therefore, I draw from the study of poetic collections and anthologies, and I seek to refine notions of psalms collections, articulating a conception of the collection. A collection, I propose, is more than a set of psalms with intertextual resonances, but a set of psalms framed and organized as belonging together, which creates an expectation of commonality and forms a new work, not just a set of previous works. This new work and one’s experience of it derives from its constituent poems. Through the collection, the compiler coopts and extends the themes and potentiality of the constituent poems and harnesses the intertextual connections. The collection is non-narrative, built on paratactic juxtapositions, marked primarily by framing devices, and the lead psalm shapes impressions of the whole as both microcosm and lens to the collection. The method employed in this study is literary, attending to manuscript evidence and spacing, poetic analysis, and literary connections. However, I have chosen not to examine the Elohistic collection in isolation, but in comparison to another ancient collection, TH 1-42, utilizing Jonathan Z. Smith’s method of comparison. I compare the Elohistic collection to TH 1-42 because TH 1-42 is an ancient corollary, in contrast to more modern and western models, and is a return to where Wilson began his study. The result of this approach is the picture of a collection that amplifies or extends the thematic emphasis and effective potential of its constituent poems. The collection is a poetic expression itself, discerned gradually. The cumulative collection is encapsulated in the lead psalm, the synecdochic lead

Is global poverty a crime against humanity?

Pogge has repeatedly compared the causes of global poverty with historical crimes against humanity. This claim, however, has been treated as mere rhetoric. This article argues that there are good reasons to take it seriously. It does this by comparing Pogge’s thesis on the causes of global poverty with the baseline definition of crimes against humanity found in international law, especially the Rome Statute of the International Criminal Court. It argues that the causes of global poverty are comparable with the crimes of slavery and apartheid. This has important consequences for cosmopolitan thought, as it makes the need for practical solutions to global poverty more urgent and raises questions about the global poor’s right to resist the international system by violent means

Population Pharmacokinetics and Safety of Ceftolozane-Tazobactam in Adult Cystic Fibrosis Patients Admitted with Acute Pulmonary Exacerbation

ABSTRACT Ceftolozane-tazobactam has potent activity against Pseudomonas aeruginosa , a pathogen associated with cystic fibrosis (CF) acute pulmonary exacerbations (APE). Due to the rapid elimination of many antibiotics, CF patients frequently have altered pharmacokinetics. In this multicenter, open-label study, we described the population pharmacokinetics and safety of ceftolozane-tazobactam at 3 g every 8 h (q8h) in 20 adult CF patients admitted with APE. Population pharmacokinetics were determined using the nonparametric adaptive grid program in Pmetrics for R. A 5,000-patient Monte Carlo simulation was performed to determine the probability of target attainment (PTA) for the ceftolozane component at 1.5 g and 3 g of ceftolozane-tazobactam q8h across a range of MICs using a primary threshold exposure of 60% free time above the MIC ( fT >MIC). In these 20 adult CF patients, ceftolozane and tazobactam concentration data were best described by 2-compartment models, and ceftolozane clearance (CL) was significantly correlated with creatinine clearance ( r = 0.71, P MIC, ceftolozane-tazobactam regimens of 1.5 g and 3 g q8h should achieve PTAs of ≥90% at MICs up to 4 and 8 μg/ml, respectively. Ceftolozane-tazobactam at 3 g q8h was well tolerated. These observations support additional studies of ceftolozane-tazobactam for Pseudomonas aeruginosa APE in CF patients. (This study has been registered at ClinicalTrials.gov under identifier NCT02421120.

Transpiration-Cooled Spacecraft-Insulation-Repair Fasteners

Transpiration-cooled fasteners are proposed that operate like an open-loop heat pipe (self-tapping screws, bolts, and spikes) for use in on-orbit repair of thermal- insulation of a space shuttle or other spacecraft. By limiting the temperature rise of such a fastener and of the adjacent repair material and thermal protection system, the transpiration cooling would contribute to the ability of the repair to retain its strength and integrity in the high-heat-flux, oxidizing environment of reentry into the atmosphere of the Earth. A typical fastener according to the proposal would include a hollow refractory-metal, refractory-composite, or ceramic screw or bolt, the central cavity of which would be occupied by a porous refractory- metal or ceramic plug that would act as both a reservoir and a wick for a transpirant liquid. The plug dimensions, the plug material, and the sizes of the pores would be chosen in conjunction with the transpirant liquid so that (1) capillary pumping could be relied upon to transport the liquid to the heated surface, where the liquid would be vaporized, and (2) the amount of liquid would suffice for protecting against the anticipated heat flux and integrated heat load

Republicanism and the political economy of democracy

Europe is experiencing rapidly accelerating poverty and social exclusion, following half a decade of financial crisis and austerity politics. The key problem behind Europe's malaise, in our view, is the economic disenfranchisement of large parts of its population in the winner-takes-all-society. This article proposes that we examine the contribution of republican political theory as a distinctive approach that provides us with the conceptual and normative resources to reclaim what we call the political economy of democracy, the constellation of political and economic institutions aimed at promoting broad economic sovereignty and individuals' capacities to govern their own lives. This article identifies three key ideas that together constitute a distinctively republican approach to political economy: (1) establish an economic floor; (2) impose an economic ceiling to counter excess economic inequality; and (3) democratize the governance and regulation of the main economic institutions