757 research outputs found
Michromechanics in biogenic hydrated silica: hinges and interocking devices in diatoms.
Diatoms are single-celled organisms with rigid parts in relative motion at the micrometrescale and below. These biogenic hydrated silica structures have elaborate shapes, interlocking devices, and, in some cases, hinged structures. The silica shells of the diatoms experience various forces from the environment and also from the cell itself when it grows and divides, and the form of these micromechanical parts has been evolutionarily optimized during the last 150 million years or more, achieving mechanical stability. Linking structures of several diatom species such as Aulacoseira, Corethron, and Ellerbeckia are presented in high-resolution SEM images and their structure and presumed functions are correlated. Currently, the industry for micro- and nanoelectromechanical devices (MEMS and NEMS) puts great effort into investigating tribology on the micro- and nanometre scale. It is suggested that micro- and nanotribologists meet with diatomists to discuss future common research attempts regarding biomimetic ideas and approaches for novel and/or improved MEMS and NEMS with optimized tribological properties
The Response of Retailers in Scotland to the Standardised Packaging of Tobacco Products Regulations and Tobacco Products Directive
Introduction With most marketing channels prohibited, the retail environment has assumed greater importance for tobacco companies, even in markets with a ban on the open display of tobacco products. Research has yet to qualitatively explore how retailers respond to standardized packaging in a country where this has been introduced. Methods As part of the DISPLAY study, face-to-face interviews were conducted with 24 small retailers in Scotland between May 23 and June 26, 2017; the interviews were conducted after The Standardised Packaging of Tobacco Products Regulations and the Tobacco Products Directive were fully implemented. Results We found high retailer compliance with the legislation. With price-marked packs and packs containing less than 20 cigarettes and 30 g of rolling tobacco banned, retailers stated that this helped simplify ordering and stock management. The removal of price-marked packs also allowed them some flexibility to set their own prices, but many chose to stick closely to recommended retail price in order to remain competitive and avoid complaints from customers. In contrast to one of the tobacco industry’s arguments against standardized packaging, most retailers suggested that transaction times had not increased, even though the changes had only recently come into force. Conclusions This study challenges some of the arguments used against standardized packaging and provides an insight into the storage and pricing strategies adopted by retailers following the removal of price-marked packs. Implications This study explores the response of the retailers to the introduction of standardized tobacco packaging and provides an insight into the storage and pricing strategies adopted by retailers following the removal of price-marked packs. It explores the importance of the retailer in tobacco companies’ desire to maintain tobacco sales and challenges some of the arguments used against standardized packaging, such as an increase in transaction times. Countries seeking to introduce standardized packaging should monitor the experiences of retailers, preferably from preimplementation through to post implementation, to help understand how retailers respond to this policy and to inform compliance
CO and C_2 Absorption Toward W40 IRS 1a
The H II region W40 harbors a small group of young, hot stars behind roughly
9 magnitudes of visual extinction. We have detected gaseous carbon monoxide
(CO) and diatomic carbon (C_2) in absorption toward the star W40 IRS 1a. The
2-0 R0, R1, and R2 lines of 12CO at 2.3 micron were measured using the CSHELL
on the NASA IR Telescope Facility (with upper limits placed on R3, R4, and R5)
yielding an N_CO of (1.1 +/- 0.2) x 10^18 cm^-2. Excitation analysis indicates
T_kin > 7 K. The Phillips system of C_2 transitions near 8775 Ang. was measured
using the Kitt Peak 4-m telescope and echelle spectrometer. Radiative pumping
models indicate a total C_2 column density of (7.0 +/- 0.4) x 10^14 cm^-2, two
excitation temperatures (39 and 126 K), and a total gas density of n ~ 250
cm^-3. The CO ice band at 4.7 micron was not detected, placing an upper limit
on the CO depletion of delta < 1 %. We postulate that the sightline has
multiple translucent components and is associated with the W40 molecular cloud.
Our data for W40 IRS 1a, coupled with other sightlines, shows that the ratio of
CO/C_2 increases from diffuse through translucent environs. Finally, we show
that the hydrogen to dust ratio seems to remain constant from diffuse to dense
environments, while the CO to dust ratio apparently does not.Comment: To appear in The Astrophysical Journal 17 pages total, 5 figures Also
available at http://casa.colorado.edu/~shuping/research/w40/w40.htm
An Optical/Near-Infrared Study of Radio-Loud Quasar Environments II. Imaging Results
We use optical and near-IR imaging to examine the properties of the
significant excess population of K>=19 galaxies found in the fields of 31 z=1-2
radio-loud quasars by Hall, Green & Cohen (1998). The excess occurs on two
spatial scales: a component at <40'' from the quasars significant compared to
the galaxy surface density at >40'' in the same fields, and a component roughly
uniform to ~100'' significant compared to the galaxy surface density seen in
random-field surveys in the literature. The r-K color distributions of the
excess galaxy populations are indistinguishable and are significantly redder
than the color distribution of the field population.
The excess galaxies are consistent with being predominantly early-type
galaxies at the quasar redshifts, and there is no evidence that they are
associated with intervening MgII absorption systems. The average excess within
0.5 Mpc (~65'') of the quasars corresponds to Abell richness class ~0 compared
to the galaxy surface density at >0.5 Mpc from the quasars, and to Abell
richness class ~1.5 compared to that from the literature.
We discuss the spectral energy distributions (SEDs) of galaxies in fields
with data in several passbands. Most candidate quasar-associated galaxies are
consistent with being 2-3 Gyr old early-types at the quasar redshifts of z~1.5.
However, some objects have SEDs consistent with being 4-5 Gyr old at z~1.5, and
a number of others are consistent with ~2 Gyr old but dust-reddened galaxies at
the quasar redshifts. These potentially different galaxy types suggest there
may be considerable dispersion in the properties of early-type cluster galaxies
at z~1.5. There is also a population of galaxies whose SEDs are best modelled
by background galaxies at z>2.5.Comment: Accepted to ApJ; 54 pages including 30 figures; 2 color GIF files
available separately; also available from
http://www.astro.utoronto.ca/~hall/thesis.htm
The role of alcohol packaging as a health communications tool: An online cross-sectional survey and experiment with young adult drinkers in the United Kingdom
Introduction Alcohol packaging is a potentially valuable means of communicating product and health-related information, with growing academic and political interest in its role as a health communications vehicle. Methods An online cross-sectional survey and experiment were conducted with a non-probability sample of 18–35-year-old drinkers in the United Kingdom (n = 1360). The survey assessed exposure to, and engagement with, current messaging on packs, and support for displaying product and health-related information. For the randomised experiment, participants were shown, and asked questions about, a vodka bottle with either no warnings (control), small text warnings, large text warnings or pictorial (image-and-text) warnings; the main binary outcome measures were negative product appeal and social acceptability, and positive cognitive and behavioural impact. Results Two-fifths of the sample rarely or never saw on-pack health-related information, with almost three-quarters rarely or never reading or looking closely at this. There was strong support for displaying a range of product and health-related information (e.g. units, ingredients) on packs. Relative to the control, products with warnings were more likely to be perceived as unappealing and socially unacceptable, and to positively impact alcohol-related cognitions and behaviours. For example, pictorial warnings were 10 times as likely to positively influence cognitions and behaviours (AOR = 10.01, 95% CI: 8.09, 17.46). Discussion and Conclusions Alcohol packaging could have an important role in delivering health messaging. Large pictorial or text warnings may help counteract the appeal and social acceptability of alcohol products and increase awareness of risks, potentially supporting a reduction in consumption and related harms.Output Status: Forthcoming/Available Onlin
Health information, messaging and warnings on alcohol packaging: a focus group study with young adult drinkers in Scotland
Introduction: Alcohol packaging can communicate alcohol-related health information, messaging and warnings. However, there is a dearth of research exploring awareness of, and engagement with, health information and messaging on alcohol packaging, and response to novel alcohol warnings. Methods: Eight focus groups were conducted in Glasgow (Scotland) with current drinkers (n = 50), segmented by age (18–24, 25–35), gender (female, male) and social grade (ABC1, C2DE), to explore awareness and use of health information and messaging on existing packaging, and perceptions of novel front-of-package warnings differing in size (small, large), form (text-only, text and image) and message content (general, specific). Results:Unaided recall of some health information and messaging was high (e.g. units, pregnancy symbols); however, most participants did not attend to or meaningfully engage with these, viewing them as unnoticeable, obscure and ineffective. Participants were skeptical of alcohol companies’ motivations with respect to health messaging on products. They were surprised to see the novel warnings on alcohol products but generally supported their inclusion. Most thought that these warnings could increase awareness of alcohol-related harms, particularly for younger or potential drinkers. Large, combined (text and image) warnings with specific messages on the front of packaging were considered most engaging and potentially effective. Conclusions: The health-related information and messaging on alcohol packaging in Scotland is failing to inform consumers about the potential risks associated with alcohol use. Prominent warnings on alcohol packaging could help to capture attention, increase awareness of alcohol-related harms, and may support a reduction in consumption and alcohol-related harms
Health information, messaging and warnings on alcohol packaging: a focus group study with young adult drinkers in Scotland. Key findings report for Alcohol Focus Scotland.
Updated resonance photo-decay amplitudes to 2 GeV
We present the results of an energy-dependent and set of single-energy
partial-wave analyses of single-pion photoproduction data. These analyses
extend from threshold to 2 GeV in the laboratory photon energy, and update our
previous analyses to 1.8 GeV. Photo-decay amplitudes are extracted for the
baryon resonances within this energy range. We consider two photoproduction sum
rules and the contributions of two additional resonance candidates found in our
most recent analysis of elastic scattering data. Comparisons are made
with previous analyses.Comment: Revtex, 26 pages, 3 figures. Postscript figures available from
ftp://clsaid.phys.vt.edu/pub/pr or indirectly from
http://clsaid.phys.vt.edu/~CAPS
Measurement of microbial activity in soil by colorimetric observation of in situ dye reduction: an approach to detection of extraterrestrial life
BACKGROUND: Detecting microbial life in extraterrestrial locations is a goal of space exploration because of ecological and health concerns about possible contamination of other planets with earthly organisms, and vice versa. Previously we suggested a method for life detection based on the fact that living entities require a continual input of energy accessed through coupled oxidations and reductions (an electron transport chain). We demonstrated using earthly soils that the identification of extracted components of electron transport chains is useful for remote detection of a chemical signature of life. The instrument package developed used supercritical carbon dioxide for soil extraction, followed by chromatography or electrophoresis to separate extracted compounds, with final detection by voltammetry and tandem mass-spectrometry. RESULTS: Here we used Earth-derived soils to develop a related life detection system based on direct observation of a biological redox signature. We measured the ability of soil microbial communities to reduce artificial electron acceptors. Living organisms in pure culture and those naturally found in soil were shown to reduce 2,3-dichlorophenol indophenol (DCIP) and the tetrazolium dye 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt (XTT). Uninoculated or sterilized controls did not reduce the dyes. A soil from Antarctica that was determined by chemical signature and DNA analysis to be sterile also did not reduce the dyes. CONCLUSION: Observation of dye reduction, supplemented with extraction and identification of only a few specific signature redox-active biochemicals such as porphyrins or quinones, provides a simplified means to detect a signature of life in the soils of other planets or their moons
Cancer prevention and therapy through the modulation of the tumor microenvironment
Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer
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