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Reducing food portion size could reduce energy intake. However it is unclear at what point consumers respond to reductions by increasing intake of other foods. We predicted that a change to a served portion size would only result in significant additional eating within the same meal if the resulting portion size was no longer visually perceived as ‘normal’. Participants in two crossover experiments (Study 1: N = 45; Study 2: N = 37; adults, 51% female) were served different sized lunchtime portions on three occasions that were perceived by a previous sample of participants as ‘large-normal’, ‘small-normal’, and ‘smaller than normal’ respectively. Participants were able to serve themselves additional helpings of the same food (Study 1), or dessert items (Study 2). In Study 1 there was a small but significant increase in additional intake when participants were served the ‘smaller than normal’ compared to the ‘small-normal’ portion, m difference = 39 kcal, p = .002, d = 0.35, but there was no significant difference between the ‘small-normal’ and ‘large-normal’ conditions, m difference = 20 kcal, p = .08, d = 0.24. A similar pattern was observed in Study 2: m difference = 36 kcal, p = .06, d = 0.18; m difference = 20 kcal, p = .26, d = 0.10. However, smaller portion sizes were each associated with a significant reduction in total meal intake. The findings provide preliminary evidence that reductions that result in portions appearing ‘normal’ in size may limit additional eating, but confirmatory research is needed. (250/250 words)
The Southern Hemisphere VLBI Experiment (or SHEVE) was a joint US-Australian-South African venture with both astronomy and geodesy goals. The principle astronomy goal was to make models or maps of the following sources: at 2.3 GHz (with six antennas and 9 usable baselines) – Centaurus A (the nearest active galaxy), Circinus X-1 (a flaring binary), the VELA pulsar, and 26 other active galactic nuclei and quasars; at 8.4 GHz (only one baseline) – Centaurus A and the galactic center.
Six radio telescopes were operated as the first southern hemisphere VLBI array in April and May 1982. Observations were made at 2.3 and 8.4 Ghz. This array produced VLBI images of 28 southern hemisphere radio sources, high accuracy VLBI geodesy between southern hemisphere sites, and subarcsecond radio astrometry of celestial sources south of declination −45 degrees. This paper discusses only the astrophysical aspects of the experiment.
VLBI observations of the nucleus of Centaurus A were made in April, 1982 at two frequencies with an array of five Australian radio antennas as part of the Southern Hemisphere VLBI Experiment (SHEVE). Observations were undertaken at 2.29 GHz with all five antennas, while only two were operational at 8.42 GHz. The 2.29 GHz data yielded significant information on the structure of the nuclear jet. At 8.42 GHz a compact unresolved core was detected as well.
Latest Sandbian to early Katian sequences across Laurentia's epicontinental sea exhibit a transition from lithologies characterized as ‘warm-water’ carbonates to those characterized as ‘cool-water'carbonates. This shift occurs across the regionally recognized M4/M5 sequence stratigraphic boundary and has been attributed to climatic cooling and glaciation, basin reorganization and upwelling of open ocean water, and/or increased water turbidity and terrigenous input associated with the Taconic tectophase. Documentation of oxygen isotopic trends across the M4/M5 and through bracketing strata provides a potential means of distinguishing among these alternative scenarios; however, oxygen isotopic records generated to date have failed to settle the debate. This lack of resolution is because δ18O records are open to multiple interpretations and potentially confounding factors related to local environmental conditions have not been tested by examining the critical interval in multiple areas and different depositional settings. To begin to address this shortcoming, we present new species-specific and mixed assemblage conodont δ18O values in samples spanning the M4/M5 boundary from the Upper Mississippi Valley, Alabama, and Virginia. The new results are combined with previous studies, providing a record of δ18O variability across SE Laurentia. The combined dataset allows us to test for regional trends at a resolution not previously available. Our results document a ~1.5‰ decrease in values across Laurentia instead of increasing δ18O values across the M4/M5 as predicted in various ‘cool-water’ scenarios. In short, these results do not support a shift to ‘cool-water’ conditions as an explanation for changes in early Katian carbonates across the M4/M5.
We present our high-resolution radio-continuum and X-ray study of supernova remnants (SNRs) in the Magellanic Clouds (MCs). These investigations are based on Australia Telescope Compact Array (ATCA) radio-continuum and ROSAT X-ray observations. Our main aim is to study a complete sample of the MC SNRs and H II regions.
30 Doradus is a giant H II region in the Large Magellanic Cloud (Bode 1801). It is the nearest extragalactic giant H II region and the location of active star formation. The complex nature of this extended region provides an excellent opportunity to investigate the impact of massive stars on the structure of the interstellar medium. Specifically the presence of supernova remnants (SNRs) is expected to play an important role.
This article updates and expands the literature on the impact of production quotas. Unlike many of the early studies, our focus is largely on the removal of production quota programs. We study cases wherein production quota programs have been eliminated and quota owners were compensated for their losses. Specifically, we examine (1) production quotas in both the absence and presence of trade, (2) production quota buyouts (three case studies), (3) sources of funding, and (4) general equilibrium considerations. A fifth section briefly discusses externalities, the interpretation of consumer surplus measures, and the nature of conducting economic analyses of addictive goods.
This article discusses the magnitude and rate of change of radiocarbon reservoir ages from the surface ocean in the South Pacific during the Holocene. 14C reservoir ages are calculated from paired U/Th and 14C measurements. Seventeen pairs of coral dates were determined from samples collected on Rendova and Tetepare Islands, in the Solomon Islands, and from Espiritu Santo Island, Vanuatu. The samples are all Holocene in age, with 230Th ages ranging from about 400 to 9400 BP. Samples were collected as drill cores or surface outcrops. About half of the surface samples appear to have incorporated modern carbon through postdepositional recrystallization. Two of the core samples were also affected by carbon exchange. The Holocene 14C reservoir ages observed in this data set show stable values for the last 3000 yr, and substantial variability from 5000–6000 BP (~100 to ~950 14C yr). Persistent low values (<200 14C yr) were observed for samples from 7000–8000 BP. We attribute these variations to temporal changes in lateral advection and vertical mixing, and possibly to local environmental conditions related to the interplay between sea-level rise and episodic uplift, characteristic of all the coral localities.
VLBI observations of the nucleus of Centaurus A have been made at three southern hemisphere observatories. Since Centaurus A is the nearest active galaxy, VLBI investigations are important because the physical processes in the nucleus can be studied in greater linear detail than in other similar galaxies. Previous VLBI observations of Centaurus A have been hampered by its southerly declination (−43°) and the sparsity of VLBI capability in the southern hemisphere, leading to only scattered single point u, v coverage. This paper presents results from the early stages of development of a southern hemisphere VLBI network.
Uranium dioxide, as the standard nuclear fuel in pressurized water reactors, motivates intensive research to get further insight into the link between radiation damage and microstructure evolution of the material. Cerium dioxide is often considered as a non-radioactive model material for uranium dioxide, for which the experimental study of radiation damage could be performed more easily. Using first-principles calculations based on the density functional theory (DFT) and its DFT+U variant, we compare these two oxides in terms of point defect formation.
The presence of an atmosphere, initially suggested based on limb darkening by Sola (1904) and later by the presence of methane spectral lines by Kuiper (1944), has long given Titan a special place in the minds of planetary geologists. The first close-up images were obtained by Pioneer 11 in 1979 (Gehrels et al., 1980), confirming a substantial atmosphere. These early observations led to the diversion of the trajectory of the Voyager I spacecraft to a closer encounter with Titan in 1980. Although the visible cameras on Voyager also had difficulty seeing Titan's surface (Richardson et al., 2004), radio occultation experiments suggested a surface pressure of 1.5 bars and temperature near 95 K (Lindal et al., 1983). These results were exciting because, for a methane mixing ratio of a few percent at the surface (Hunten, 1978), they placed methane's partial pressure near its triple point. Thus, like water on Earth, solid, liquid, and gaseous methane could potentially exist in Titan's environment. Ethane, which is the main product of methane photolysis, can also be liquid under these conditions. The presence of condensable volatiles in Titan's thick atmosphere opens the door for active fluvial, lacustrine, and pluvial processes that can shape its landscape with similar morphologies to those we find on Earth.
Prompted by the exciting results of the Voyager mission and the nearly two decades of Earth-based imaging campaigns that followed, NASA/ESA launched the Cassini-Huygens mission to Saturn in 1997. To penetrate Titan's thick atmosphere, Cassini is equipped with a Ku-band radar capable of obtaining images of the surface at a scale of 300 meters.
We provide a theoretical and empirical comparison of two historic production quota buyouts: the 2002 US Peanut Quota Buyout and the 2004 US Tobacco Quota Buyout. Producer compensation under the US Peanut Quota Buyout came from the treasury while the US Tobacco Buyout was paid for by a consumer tax (i.e., tobacco tax). Given these two buyouts, an important question arises: How does the method of compensation affect distribution and efficiency? Producers, consumers, and society favor a treasury buyout (TB) for several reasons. Producers are compensated considerably more under a TB, consumers are not burdened with the charge of funding the buyout, and society does not face additional efficiency losses due to the buyout.
This article analyzes the impact of removing the U.S. tobacco program in both a partial and general welfare economics framework. In a partial-equilibrium framework, a consumer tax-funded quota buyout can result in producer gains, consumer losses, net losses resulting from higher prices, and deadweight losses. In a general-equilibrium framework, society can gain from the buyout resulting from considerable potential savings from reduced healthcare costs attributable to a reduction in smoking. Additionally, we present a model that addresses the addictive qualities of tobacco while considering the effects of the quota buyout. We also conclude that another possible effect of the buyout is an increase in worker productivity because employees who are able to quit smoking reduce the amount of smoking-related sick days taken.
PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed 2.5-m optical/infrared telescope to be located at Dome C on the Antarctic plateau. Conditions at Dome C are known to be exceptional for astronomy. The seeing (above ∼30 m height), coherence time, and isoplanatic angle are all twice as good as at typical mid-latitude sites, while the water-vapour column, and the atmosphere and telescope thermal emission are all an order of magnitude better. These conditions enable a unique scientific capability for PILOT, which is addressed in this series of papers. The current paper presents an overview of the optical and instrumentation suite for PILOT and its expected performance, a summary of the key science goals and observational approach for the facility, a discussion of the synergies between the science goals for PILOT and other telescopes, and a discussion of the future of Antarctic astronomy. Paper II and Paper III present details of the science projects divided, respectively, between the distant Universe (i.e. studies of first light, and the assembly and evolution of structure) and the nearby Universe (i.e. studies of Local Group galaxies, the Milky Way, and the Solar System).
The incidence of myocardial infarctions and influenza follow similar seasonal patterns. To determine if acute myocardial infarctions (AMIs) and ischaemic strokes are associated with influenza activity, we built time-series models using data from the Nationwide Inpatient Sample. In these models, we used influenza activity to predict the incidence of AMI and ischaemic stroke. We fitted national models as well as models based on four geographical regions and five age groups. Across all models, we found consistent significant associations between AMIs and influenza activity, but not between ischaemic strokes and influenza. Associations between influenza and AMI increased with age, were greatest in those aged >80 years, and were present in all geographical regions. In addition, the natural experiment provided by the second wave of the influenza pandemic in 2009 provided further evidence of the relationship between influenza and AMI, because both series peaked in the same non-winter month.
To assess the association of the acute-phase protein biomarkers, C-reactive protein (CRP) and α1-acid glycoprotein (AGP), with anaemia in children aged 6–59·9 months in Papua New Guinea.
A nationally representative household-based cross-sectional survey of children aged 6–59·9 months was used to assess the relationships between various combinations of elevated CRP (>5 mg/l) and AGP (>1·2 g/l) with anaemia. Logistic regression was used to determine if other factors, such as age, sex, measures of anthropometry, region, urban/rural residence and household size, modified or confounded the acute-phase protein–anaemia association.
Papua New Guinea.
A total of 870 children aged 6–59·9 months from the 2005 Papua New Guinea National Micronutrient Survey were assessed.
The following prevalence estimates were found: anaemia 48 %; elevated CRP 32 %; and elevated AGP 33 %. Children with elevated CRP had a prevalence of anaemia of 66 % compared with children with normal CRP who had a prevalence of 40 %. Corresponding estimates for AGP were 61 % and 42 %, respectively. Similar results were found with combinations of elevated CRP and AGP. The higher prevalence of anaemia in children with elevated CRP and/or AGP was still present after controlling for confounders.
Elevated levels of CRP and AGP were significantly associated with a higher prevalence of anaemia in the children surveyed. There are no expert group recommendations on whether to or how to account for markers of inflammation in presenting results on anaemia prevalence. Additional research would be helpful to clarify this issue.
Proton implantation and thermal annealing of silicon result in the formation of a specific type of extended defect involving hydrogen, named “platelets”. These defects have been related to the exfoliation mechanism on which a newly developed process to transfer thin films of silicon onto various substrates is based. In a previous paper, we have shown that these platelets undergo a quasi-conservative Ostwald ripening upon annealing. The measurement of the pressure within such pressurised gas-filled cavities is important to understand and simulate both the growth of these defects and the exfoliation mechanism. To extract this pressure from TEM studies, we have developed and tested an analogy between the platelets and a well-known 2D defect: a dislocation loop. The comparison between simulations of the image of the strain field surrounding a fictitious dislocation loop and experimental TEM images of the platelets shows that the platelets can be described by a Burgers vector of about 0.6nm. Moreover, this vector can be used to deduce the pressure of the molecular hydrogen within a platelet. A typical value of 10 GPa is found for a platelet of 20 nm in diameter at room temperature. Consequently, the atomic density of hydrogen within a platelet and the total number of hydrogen trapped by a population of platelet can be calculated and give reasonable values when compared to the implanted dose.