Cost effective use of liquid nitrogen in cryogenic wind tunnels

A method of reliquefying from 12 to 19% of the nitrogen exhaust gas from a cryogenic wind tunnel has been developed. Technical feasibility and cost effectiveness of the system depends on performance of an innovative positive displacement expander which requires scale model testing to confirm design studies. The existing cryogenic system at the 0.3-m transonic cryogenic tunnel has been surveyed and extensive upgrades proposed. Upgrades are generally cost effective and may be implemented immediately since they are based on established technology

Effects of digital engagement on the quality of life of older people

It is often asserted that older people's quality of life (QOL) is improved when they adopt information and communication technology (ICT) such as the Internet, mobile phones and computers. Similar assumptions are made about older people's use of ICT-based care such as telecare and telehealth. To examine the evidence around these claims, we conducted a scoping review of the academic and grey literature, coving the period between January 2007 and August 2014. A framework analysis approach, based on six domains of QOL derived from the ASCOT and WHOQOL models, was adopted to deductively code and analyse relevant literature. The review revealed mixed results. Older people's use of ICT in both mainstream and care contexts has been shown to have both positive and negative impacts on several aspects of QOL. Studies which have rigorously assessed the impact of older people's use of ICT on their QOL mostly demonstrate little effect. A number of qualitative studies have reported on the positive effects for older people who use ICT such as email or Skype to keep in touch with family and friends. Overall, the review unearthed several inconsistencies around the effects of older people's ICT use on their QOL, suggesting that implicit agreement is needed on the best research methods and instrumentation to adequately describe older people's experiences in today's digital age. Moreover, the available evidence does not consider the large number of older people who do not use ICT and how non-use affects QOL

Mitochondrial Sirtuins and Their Relationships with Metabolic Disease and Cancer

Significance: Maintenance of metabolic homeostasis is critical for cellular and organismal health. Proper regulation of mitochondrial functions represents a crucial element of overall metabolic homeostasis. Mitochondrial sirtuins (SIRT3, SIRT4, and SIRT5) play pivotal roles in promoting this homeostasis by regulating numerous aspects of mitochondrial metabolism in response to environmental stressors. Recent Advances: New work has illuminated multiple links between mitochondrial sirtuins and cancer. SIRT5 has been shown to regulate the recently described post-translational modifications succinyl-lysine, malonyl-lysine, and glutaryl-lysine. An understanding of these modifications is still in its infancy. Enumeration of SIRT3 and SIRT5 targets via advanced proteomic techniques promises to dramatically enhance insight into functions of these proteins. Critical Issues: In this review, we highlight the roles of mitochondrial sirtuins and their targets in cellular and organismal metabolic homeostasis. Furthermore, we discuss emerging roles for mitochondrial sirtuins in suppressing and/or promoting tumorigenesis, depending on the cellular and molecular context. Future Directions: Currently, hundreds of potential SIRT3 and SIRT5 molecular targets have been identified in proteomic experiments. Future studies will need to validate the major targets of these enzymes, and elucidate how acetylation and/or acylation modulate their functionality. A great deal of interest exists in targeting sirtuins pharmacologically; this endeavor will require development of sirtuin-specific modulators (activators and inhibitors) as potential treatments for cancer and metabolic disease. Antioxid. Redox Signal. 22, 1060?1077.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140306/1/ars.2014.6213.pd

Cost-effective use of liquid nitrogen in cryogenic wind tunnels, phase 2

Cryogenic seal tests were performed and Rulon A was selected for the subject nutating positive displacement expander. A four-chamber expander was designed and fabricated. A nitrogen reliquefier flow system was also designed and constructed for testing the cold expander. Initial tests were unsatisfactory because of high internal friction attributed to nutating Rulon inlet and outlet valve plates. Replacement of the nutating valves with cam-actuated poppet valves improved performance. However, no net nitrogen reliquefaction was achieved due to high internal friction. Computer software was developed for accurate calculation of nitrogen reliquefaction from a system such as that proposed. These calculations indicated that practical reliquefaction rates of 15 to 19 percent could be obtained. Due to mechanical problems, the nutating expander did not demonstrate its feasibility nor that of the system. It was concluded that redesign and testing of a smaller nutating expander was required to prove concept feasibility

Quotient Hash Tables - Efficiently Detecting Duplicates in Streaming Data

This article presents the Quotient Hash Table (QHT) a new data structure for duplicate detection in unbounded streams. QHTs stem from a corrected analysis of streaming quotient filters (SQFs), resulting in a 33\% reduction in memory usage for equal performance. We provide a new and thorough analysis of both algorithms, with results of interest to other existing constructions. We also introduce an optimised version of our new data structure dubbed Queued QHT with Duplicates (QQHTD). Finally we discuss the effect of adversarial inputs for hash-based duplicate filters similar to QHT.Comment: Shorter version was accepted at SIGAPP SAC '1

From Cheechako to Koviashuvik and Shahóon: Wilderness and the Alaskan Sublime in Ken Ilgunas’s Walden on Wheels and Ernestine Hayes’s Blonde Indian

As “America's last frontier”, Alaska provides an opportunity to revisit the pioneer past in a challenging and awe-inspiring landscape (Nash 2014). While the Alaskan nature illustrates the inhospitable and terrifying features of the Burkean sublime, the Trans-Alaska Pipeline and air traffic exemplify the presence of technology in a state that has been perceived as “pure” or “untrammelled”, a view associated with the natural sublime. For these reasons, contemporary U.S. memoirs including descriptions of Alaska constitute suitable case studies for analyzing the rhetorical affordances and limits of the sublime for figuring (non-)human materiality and for questioning the nature/culture divide. While the Anthropocene and the sublime produce senses of excess, overwhelm, and disorientation (Purdy 2015), the memoir, as human-centered and referring to an “extra-textual reality” (Couser 2011), is a privileged genre to investigate the Anthropocene sublime and these related affects. Through a rhetorical and narratological—mainly informed by recent insights from econarratology, which study the place and function of materiality and (non-)human agency in literary texts while rhetorically alerting readers to an ethics of care for (non-)human otherness (James and Morel 2020)—analysis of Ken Ilgunas's Walden on Wheels (2013) and Ernestine Hayes's Blonde Indian (2006) as well as of their uses of the notions of koviashuvik and shahóon, this paper will argue that the natural sublime and the American concept of wilderness are still problematic and divisive, and will present the “haptic sublime” (McNee 2016) and “stuplime” (Ngai 2005) as contributing to imagining a more participative and “ecological sublime” (Hitt 1999)

Dans les lignes, à travers les âges Guy Delhasse raconte Liège en toutes lettres

Dans Liège en toutes lettres, Guy Delhasse raconte comment les écrivain(e)s ont écrit la ville de Liège depuis 1823. De ses vies ouvrière, politique, religieuse, sociale, scolaire à celles de ses commerces, de ses transports, de ses arts, et de sa gastronomie, Liège y rayonne à tous les coins de rues et dans pléthores de lignes d’auteurs et autrices (in)connu(e)s pour se graver dans nos mémoires