5,389 research outputs found

    Indentation of ellipsoidal and cylindrical elastic shells

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    Thin shells are found in nature at scales ranging from viruses to hens’ eggs; the stiffness of such shells is essential for their function. We present the results of numerical simulations and theoretical analyses for the indentation of ellipsoidal and cylindrical elastic shells, considering both pressurized and unpressurized shells. We provide a theoretical foundation for the experimental findings of Lazarus et al. [Phys. Rev. Lett. (submitted)] and for previous work inferring the turgor pressure of bacteria from measurements of their indentation stiffness; we also identify a new regime at large indentation. We show that the indentation stiffness of convex shells is dominated by either the mean or Gaussian curvature of the shell depending on the pressurization and indentation depth. Our results reveal how geometry rules the rigidity of shells

    Simultaneous measurement of multiple parameters of a subwavelength structure based on the weak value formalism

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    A mathematical extension of the weak value formalism to the simultaneous measurement of multiple parameters is presented in the context of an optical focused vector beam scatterometry experiment. In this example, preselection and postselection are achieved via spatially-varying polarization control, which can be tailored to optimize the sensitivity to parameter variations. Initial experiments for the two-parameter case demonstrate that this method can be used to measure physical parameters with resolutions at least 1000 times smaller than the wavelength of illumination

    Subtyping somatic tinnitus: a cross-sectional UK cohort study of demographic, clinical and audiological characteristics

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    Somatic tinnitus is the ability to modulate the psychoacoustic features of tinnitus by somatic manoeuvres. The condition is still not fully understood and further identification of this subtype is essential, particularly for the purpose of establishing protocols for both its diagnosis and treatment. This study aimed to investigate the characteristics of somatic tinnitus within a large UK cohort using a largely unselected sample. We believe this to be relatively unique in comparison to current literature on the topic. This was investigated by using a total of 608 participant assessments from a set of recognised tinnitus and audiology measures. Results from a set of chi-square tests of association found that amongst the individuals with somatic tinnitus, a higher proportion had pulsatile tinnitus (different from heartbeat), were under the age of 40, reported variation in the loudness of their tinnitus and reported temporomandibular joint (TMJ) disorder. The same pattern of results was confirmed using a multivariate analysis of the data based on logistic regression. These findings have strong implications towards the profiling of somatic tinnitus as a distinct subtype of general tinnitus

    A Mindful Environmental Jurisprudence?: Speculations on the Application of Gandhi’s Thought to MCWC v. Nestlé

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    We attempt to engage modern legal reasoning with Gandhi’s thought. We hope to speculate on what jurisprudence would look like if it were more mindful of the concepts central to Gandhi’s thought. By using Gandhi as an intellectual anchor, we hope to take a step toward creating a more “mindful jurisprudence” that implicitly incorporates into its reasoning the needs of environmental stewardship, disempowered populations, and the poverty-stricken. Because Gandhi’s thought has been discussed at length in environmental justice campaigns, we begin this effort by examining the relationship between environmental law and Gandhi’s thought. Given Gandhi’s commentaries on exploitative and oppressive social relationships, we focus on the intersections of law, environment, and economy. We use the recent suit, Michigan Citizens for Water Conservation v. Nestlé Waters North America, Inc. (MCWC), as a case study to which we apply themes from Gandhi’s thought. Applying Gandhi’s thought to MCWC is useful for two reasons. First, MCWC contains several core legal doctrines that appear regularly in environmental cases (and in case law more broadly). As a result, our applications of Gandhi’s thought directly apply to other environmental cases. Second, the case involves a defendant-corporation’s encroachment onto a stream used by local plaintiff-civilians. Environmental justice campaigns often involve similar factual circumstances in which local people resist large outsider organizations. Therefore, using Gandhi’s thought, we examine the legal reasoning in MCWC to identify taken-for-granted assumptions about environment and society that favor outside parties over local residents

    Measures to eradicate multidrug-resistant organism outbreaks: How much does it cost?

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    This study aimed to assess the economic burden of infection control measures that succeeded in eradicating multidrug-resistant organisms (MDROs) in emerging epidemic contexts in hospital settings. The MEDLINE, EMBASE and Ovid databases were systematically interrogated for original English-language articles detailing costs associated with strict measures to eradicate MDROs published between 1 January 1974 and 2 November 2014. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Overall, 13 original articles were retrieved reporting data on several MDROs, including glycopeptide-resistant enterococci (n = 5), carbapenemase-producing Enterobacteriacae (n = 1), methicillin-resistant Staphylococcus aureus (n = 5), and carbapenem-resistant Acinetobacter baumannii (n = 2). Overall, the cost of strict measures to eradicate MDROs ranged from €285 to €57 532 per positive patient. The major component of these overall costs was related to interruption of new admissions, representing €2466 to €47 093 per positive patient (69% of the overall mean cost; range, 13-100%), followed by mean laboratory costs of €628 to €5849 (24%; range, 3.3-56.7%), staff reinforcement costs of €6204 to €148 381 (22%; range, 3.3-52%), and contact precautions costs of €166 to €10 438 per positive patient (18%; range, 0.7-43.3%). Published data on the economic burden of strict measures to eradicate MDROs are limited, heterogeneous, and weakened by several methodological flaws. Novel economic studies should be performed to assess the financial impact of current policies, and to identify the most cost-effective strategies to eradicate emerging MDROs in healthcare facilities

    Associations of Abdominal Muscle Area and Radiodensity with Adiponectin and Leptin: The Multiethnic Study of Atherosclerosis.

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    ObjectiveThis study examined the associations of muscle area and radiodensity with adiponectin and leptin.MethodsA total of 1,944 participants who enrolled in the Multi-Ethnic Study of Atherosclerosis underwent computed tomography to quantify body composition and measurements of adiponectin, leptin, interleukin-6, C-reactive protein, and resistin.ResultsThe mean age and BMI of participants were 64.7 years and 28.1 kg/m2 and 49% were female. With adjustment for age, gender, race/ethnicity, traditional cardiovascular disease risk factors, inflammatory biomarkers, physical activity, and sedentary behavior, a 1-SD increment in total abdominal, stability, and locomotor muscle area was associated with a 19%, 17%, and 12% lower adiponectin level, respectively (P < 0.01 for all) but not leptin (P > 0.05). Muscle radiodensity was more robustly associated with adiponectin and leptin in the multivariable linear regression models. That is, with full adjustment for all covariates, a 1-SD increment in total abdominal, stability, and locomotor muscle radiodensity was associated with a 31%, 31%, and 18% lower adiponectin level (P < 0.01 for all) and a 6.7%, 4.6%, and 8.1% higher leptin level (P < 0.05 for all), respectively.ConclusionsThe data suggest that increases in muscle area and radiodensity may have positive impacts on chronic inflammation and, in turn, reduce the risk of cardiometabolic disease

    Preliminary studies of geochemical tools to traceability of Sicilian honey

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    Today is increasing the attention of consumers for the origin of food and high reputation of products with a distinct geographical identity. Food traceability is an important issue in food safety and quality control, with impacts on food security, its quantity and overall availability. Furthermore, the possibility of tracing the origin of foodstuff is assuming an increasingly important role at the legislative level, as a tool that may allow to prove on product authenticity and to control adulteration So, establish systems to trace food or feed products through specified stages of production, processing and distribution play a key role also to ensure food safety. For these reason, in the last years, a various of analytical techniques have been tested to found ways to establish the geographical origin of different kinds of food and many works reported that the combination of different analytical methods associated a multifactorial analysis of the data seems to be the most promising system to establish univocal traceability systems. Despite, the honey is a well appreciated natural product in the world and the detection of potential fraud could be favored through tools linking the chemistry composition of this production to producing area. A relatively small number of investigations regarding traceability of honey can be found in the scientific literature. Therefore, in these contest the development of fingerprinting techniques based on the determination of the specific markers of provenance analyzed whit chemometric approach represents an interesting area of research. Recent works have been demonstrated the potentiality of the study of the distribution patterns of rare earth as a promising analytical method for traceability of food products due coherent and predictable chemical behaviour of these compounds. Also, have been demonstrated that their distribution in soil keeps unaltered in plants growing on that soil and eventually in agricultural products obtained from those plants and through the normalization of the REEs distribution, it is possible to appreciate their relative enrichments in soil-plant- agro food products The aim of the research is to observe if the REEs normalizated pattern of honey is kept unaltered respect the soils of production to establish a correlation between geographic area and honey product. In this first study the REE approach, give very intriguing results in the geographical traceability of honey samples. The results have been supported by statistical treatment. A larger study is in progress to optimize the analytical methodology and to extend the research to a major number of sample for a better geographical characterization

    Ultrafast Spectroscopy with Photocurrent Detection: Watching Excitonic Optoelectronic Systems at Work.

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    While ultrafast spectroscopy with photocurrent detection was almost unknown before 2012, in the last 3 years, a number of research groups from different fields have independently developed ultrafast electric probe approaches and reported promising pilot studies. Here, we discuss these recent advances and provide our perspective on how photocurrent detection successfully overcomes many limitations of all-optical methods, which makes it a technique of choice when device photophysics is concerned. We also highlight compelling existing problems and research questions and suggest ways for further development, outlining the potential breakthroughs to be expected in the near future using photocurrent ultrafast optical probes.A.A.B. is currently a Royal Society University Research Fellow. A.A.B. also acknowledges a VENI grant from the NWO. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 639750). C.S. acknowledges funding from the Natural Science and Engineering Research Council of Canada, the Fonds de recherche du Québec–nature et technologies, the Canada Research Chair in Organic Semiconductor Materials, and the Université de Montréal Research Chair. C.S. and E.V. acknowledge collaboration with Sachetan Tuladhar, Michelle Vezie, Sheridan Few, Jenny Nelson, Hao Li, and Eric Bittner. Finally, C.S. and E.V. acknowledge essential discussions with Andy Marcus and Julia Widom for the implementation of the two-dimensional spectroscopy apparatus.This is the author accepted manuscript. The final version is available from the American Chemical Society via http://dx.doi.org/10.1021/acs.jpclett.5b0195
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