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Mark Blythe 《Personal and Ubiquitous Computing》2014,18(4):795-808
Literary criticism places fictional work in historical, social and psychological contexts to offer insights about the way that texts are produced and consumed. Critical theory offers a range of strategies for analysing what a text says and just as importantly, what it leaves unsaid. Literary analyses of scientific writing can also produce insights about how research agendas are framed and addressed. This paper provides three readings of a seminal ubiquitous computing scenario by Marc Weiser. Three approaches from literary and critical theory are demonstrated in deconstructive, psychoanalytic and feminist readings of the scenario. The deconstructive reading suggests that alongside the vision of convenient and efficient ubiquitous computing is a complex set of fears and anxieties that the text cannot quite subdue. A psychoanalytic reading considers what the scenario is asking us to desire and identifies the dream of surveillance without intrusion. A final feminist reading discusses gender and collapsing distinctions between public and private, office and home, family and work life. None of the readings are suggested as the final truth of what Weiser was “really” saying. Rather they articulate a set of issues and concerns that might frame design agendas differently. The scenario is then re-written in two pastiches that draw on source material with very different visions of ubiquitous computing. The Sal scenario is first rewritten in the style of Douglas Adams’ Hitchhiker’s Guide to the Galaxy. In this world, technology is broken, design is poor and users are flawed, fallible and vulnerable. The second rewrites the scenarios in the style of Philip K Dick’s novel Ubik. This scenario serves to highlight what is absent in Weiser’s scenario and indeed most design scenarios: money. The three readings and two pastiches underline the social conflict and struggle more often elided or ignored in the stories told in ubicomp literature. It is argued that literary forms of reading and writing can be useful in both questioning and reframing scientific writing and design agendas. 相似文献
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Stream habitat restoration is an important tool for fisheries management in impaired lotic systems. Although small‐scale benefits of stream habitat restoration are commonly investigated, it is difficult to demonstrate population effects. The Pahsimeroi River Chinook salmon Oncorhynchus tshawytscha population was previously restricted to the lower portion of the river by multiple irrigation structures. To address fish passage issues, a combination of restoration projects was initiated including barrier removals, instream flow enhancements and installation of fish screens on diversions. The largest barrier was removed in 2009, more than doubling the amount of accessible linear habitat. We hypothesized restoration efforts would expand the distribution of spawning salmon in the Pahsimeroi River watershed, leading to a broader distribution of juveniles. We also hypothesized a broader juvenile distribution would have population effects by reducing the prevalence of density‐dependent growth and survival. Redds were documented in newly accessible habitat immediately following barrier removal and accounted for a median of 42% of all redds in the Pahsimeroi River watershed during 2009–2015. Snorkel surveys also documented juvenile rearing in newly accessible habitat. Juvenile productivity increased from a median of 64 smolts/female spawner for brood years 2002–2008 to 99 smolts/female spawner for brood years 2009–2014. Overall, results suggested increased habitat accessibility in the Pahsimeroi River broadened the distribution of spawning adult and rearing juvenile salmon and reduced the effects of density‐dependent survival. Large‐scale stream restoration efforts can have a population effect. Despite the large‐scale effort and response, habitat restoration alone is likely not sufficient to restore this population. 相似文献
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Spatially homogeneous thermal explosions governed by a three-step chain-branching kinetic model are described in the asymptotic
limit of large activation energy for a range of chain-branching cross-over temperatures. The model consists of a sequence
of chain-initiation, chain-branching and chain-termination steps. Temperature-sensitive Arrhenius kinetics is employed for
the initiation and branching steps, while the termination step has a temperature-independent rate. Marked distinctions in
structure arise as the magnitude of the chain-branching cross-over temperature is increased relative to the initial system
temperature. Attention is focused on the regime where the chain-branching cross-over temperature is close to the initial system
temperature. Results are also obtained for the fast and slow explosion limits where the two temperatures are not close.
An erratum to this article can be found at 相似文献
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J Tor-Agbidye VS Palmer MI Sabri AM Craig LL Blythe PS Spencer 《Canadian Metallurgical Quarterly》1998,55(8):583-595
Nutritional status is an important factor in modulating the metabolic fate of xenobiotics. Sulfur amino acid (SAA) deficiency has been proposed as a risk factor for human neurological diseases among protein-poor populations subsisting on the cyanophoric plant cassava. Female Sprague-Dawley rats were used to develop and define a model of SAA deficiency for use in future studies examining cassava-related neurotoxicity. Rats were kept in metabolic cages for 7-21 d and fed a balanced diet (BD) of known composition or a comparable diet selectively deficient in methionine and cystine (SAA-free diet). Animals fed the SAA-free diet failed to thrive, lost body weight, excreted porphyrinic materials, and showed a steep and persistent reduction of urinary inorganic sulfate. In contrast, animals on the BD gained body weight and maintained baseline output of urinary inorganic sulfate. Urinary thiocyanate excretion did not differ between groups, but plasma thiocyanate concentrations reached double that in SAA-deficient rats. Increased plasma thiocyanate suggests mobilization of sulfur amino acids from endogenous sources. Liver glutathione and blood cyanide concentrations were similar in animals on the BD and the SAA-deficient diet. In summary, a diet free of methionine and cystine results in increased retention of inorganic sulfur as thiocyanate and a near absence of inorganic sulfur excretion in urine. 相似文献
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Electromyography of the esophageal musculature of a cow that had been regurgitating and losing weight after correction of an esophageal obstruction was suggestive of unilateral denervation. Radiography before and after oral administration of barium sulfate revealed a dilated terminal portion of the thoracic esophagus, suggestive of a focal motility problem. Electromyography was performed on the esophageal musculature by positioning the electrode through the rumen fistula and into the thoracic esophagus and by positioning the electrode percutaneously with the aid of a tube placed in the cervical esophagus. Numerous fibrillation potentials and sharp epsilon-positive waves were detected in the muscles of the left side of the distal portions of the cervical and thoracic esophagus. During hospitalization, the cow was given alfalfa pellets, ground corn, and sodium bicarbonate through the rumen fistula 3 times each day for several weeks to maintain body weight. 相似文献
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Christopher D. Sinigalliano Jared S. Ervin Laurie C. Van De Werfhorst Brian D. Badgley Elisenda Ballesté Jakob Bartkowiak Alexandria B. Boehm Muruleedhara Byappanahalli Kelly D. Goodwin Michèle Gourmelon John Griffith Patricia A. Holden Jenny Jay Blythe Layton Cheonghoon Lee Jiyoung Lee Wim G. Meijer Rachel Noble Meredith Raith Hodon Ryu Michael J. Sadowsky Alexander Schriewer Dan Wang David Wanless Richard Whitman Stefan Wuertz Jorge W. Santo Domingo 《Water research》2013
Here we report results from a multi-laboratory (n = 11) evaluation of four different PCR methods targeting the 16S rRNA gene of Catellicoccus marimammalium originally developed to detect gull fecal contamination in coastal environments. The methods included a conventional end-point PCR method, a SYBR® Green qPCR method, and two TaqMan® qPCR methods. Different techniques for data normalization and analysis were tested. Data analysis methods had a pronounced impact on assay sensitivity and specificity calculations. Across-laboratory standardization of metrics including the lower limit of quantification (LLOQ), target detected but not quantifiable (DNQ), and target not detected (ND) significantly improved results compared to results submitted by individual laboratories prior to definition standardization. The unit of measure used for data normalization also had a pronounced effect on measured assay performance. Data normalization to DNA mass improved quantitative method performance as compared to enterococcus normalization. The MST methods tested here were originally designed for gulls but were found in this study to also detect feces from other birds, particularly feces composited from pigeons. Sequencing efforts showed that some pigeon feces from California contained sequences similar to C. marimammalium found in gull feces. These data suggest that the prevalence, geographic scope, and ecology of C. marimammalium in host birds other than gulls require further investigation. This study represents an important first step in the multi-laboratory assessment of these methods and highlights the need to broaden and standardize additional evaluations, including environmentally relevant target concentrations in ambient waters from diverse geographic regions. 相似文献