Characterizing the Food Environment in Rural Sri Lanka and its Influence on Diet Quality

Background: Food environments have been understudied in low- and middle-income countries (LMICs), but may contribute to further understanding of nutrition transitions that these countries are experiencing and how programs and policies might improve diet quality. Smallholder farmers are an especially vulnerable group, including in Sri Lanka, where there are concerns about the availability and affordability of nutritious food, especially in rural, food insecure areas, and throughout the year. The Coronavirus Disease 2019 (Covid-19) pandemic and Sri Lanka’s foreign exchange crisis of 2021 elevated these concerns further, with widely reported impacts on food supply chains and prices. Objective: This study sought to characterize the food environment in 45 Grama Niladhari Divisions (GNs) in rural Sri Lanka, in terms of food availability, food costs, and affordability, and test associations with dietary diversity among smallholder farmers. In addition to furthering the evidence base on epidemiological linkages food environments and diet quality, the study aimed to contribute contextual information to an impact evaluation of the R5N program, a World Food Programme food assistance for assets (FFA) intervention aimed at strengthening resilience among smallholders in these areas. Methods: Survey questionnaires in traditional, open-air markets and village retail shops were used to gather food availability and food price data during monthly follow-ups between December 2020 and December 2021. Food availability was assessed at baseline in terms of food variety, the presence of sufficient foods to meet food-based dietary guidance (FBDG) recommendations, and an adapted Nutrition Environment Measures for Stores-Survey (NEMS-S) score. Food costs and affordability were assessed at baseline in terms of the cost of the recommended diet (CoRD) and relative caloric prices (RCPs). This data was merged with diet data from 24-hour recalls, collected as part of the R5N impact evaluation, to test associations at baseline between dietary diversity among smallholder adults and two food environment exposures—food variety and CoRD—using multilevel Poisson regression with GN-level random intercepts. Temporal trends in food availability and CoRD were assessed over the study period and compared to secondary data from Sri Lanka’s national food price surveillance system. Seasonal variation in CoRD were assessed at the national-level before and during Covid-19, using stochastic trend models. Results: At baseline, foods to make up a healthy diet according to FBDG were highly available and affordable in the study area. CoRD was LKR 155.39 ($2.63 2011 PPP$) per person per day, representing 48% of average household food expenditure and just 15% of the households included in the R5N impact evaluation study appeared to have insufficient income to afford that diet. CoRD and food variety were not significantly associated with dietary diversity among smallholders at baseline, after adjusting for GN socio-demographic, economic, and farm size composition of study participants. In contrast, within a GN, a 10% difference in household expenditure was associated with a difference of 0.8% (95% CI: 0.5% - 1.0%) in the expected number of food groups consumed. Food availability gaps emerged in the R5N area during the second half of 2021 that may have limited physical access to sufficient food variety for FBDG, and CoRD increased by 25% the study period after adjusting for inflation, which was nearly triple the level of increase that was seen in the national price surveillance data. Covid-19 increased the volatility of CoRD nationally, though typical seasonal variation in CoRD appeared minor relative to other countries. Conclusions: Food environment exposures measured in the study were not associated with GN mean dietary diversity among smallholders in the R5N study at baseline, though household expenditure did have a significant within-GN association. This suggests that if WFP’s R5N program is successful in its attempt to improve income among smallholders, this could be sufficient to generate diet improvements. However, substantial increases in CoRD took place during the implementation of the R5N program that could alter these findings. Future work will re-examine this association, incorporating longitudinal food environment, household, and diet data

A method for analysis of fatty acids in coral

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109910/1/lno19741950846.pd

Electron capture dissociation implementation progress in fourier transform ion cyclotron resonance mass spectrometry

Successful electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applications to peptide and protein structural analysis have been enabled by constant progress in implementation of improved electron injection techniques. The rate of ECD product ion formation has been increased to match the liquid chromatography and capillary electrophoresis timescales, and ECD has been combined with infrared multiphoton dissociation in a single experimental configuration to provide simultaneous irradiation, fast switching between the two techniques, and good spatial overlap between ion, photon, and electron beams. Here we begin by describing advantages and disadvantages of the various existing electron injection techniques for ECD in FT-ICR MS. We next compare multiple-pass and single-pass ECD to provide better understanding of ECD efficiency at low and high negative cathode potentials. We introduce compressed hollow electron beam injection to optimize the overlap of ion, photon, and electron beams in the ICR ion trap. Finally, to overcome significant outgassing during operation of a powerful thermal cathode, we introduce nonthermal electron emitter-based electron injection. We describe the first results obtained with cold cathode ECD, and demonstrate a general way to obtain low-energy electrons in FT-ICR MS by use of multiple-pass EC

The social and spatial behaviour of caribou Rangifer tarandus

All animals are social at some point in their life. The causes and consequences of animal social behaviour are widely studied, but the integration of space use and spatial features of the landscape within our understanding of social behaviour is not widely studied. My thesis broadly addresses the role of spatial features of the landscape and individual-level space use traits as potential drivers of emergent social behaviour in caribou (Rangifer tarandus). First, I present a theoretical framework linking social and spatial behaviour within the context of evolutionary and behavioural ecology theory. Next, I assess the relationship between social behaviour and space use across scales, from fine-scale foraging and interactions to coarse-scale examination of how individuals and groups vary social behaviour through space and time. Overall, I found that caribou social behaviour is linked to space use and spatial behaviour in four important ways. First, I found that collective movement was an important predictor for patterns of habitat selection, where caribou tend to select foraging habitat (i.e. lichen) while alone, but to move collectively between foraging patches. Second, despite high home range overlap between caribou, and thus potential to associate, sub-groups of individuals had strong social preference for one another and formed distinct social communities. Third, based on a thirty year dataset of caribou group size, I found that group sizes varied spatially and temporally. In contrast to our expectation, groups decreased in size as a function of increasing population density, while groups tended to be larger in winter compared to summer, presumably as a result of seasonal access to foraging opportunities. Finally, I found that social network strength and habitat specialization were density-dependent, while more social individuals were habitat generalists. However, habitat specialization had a greater effect on fitness, where habitat specialists had higher fitness than habitat generalists, but only at high density. My thesis addresses questions about the relationship between social and spatial behaviour and provides a theoretical framework for future studies to address similar questions. Throughout my thesis I also argue for the integration of various diverse ecological fields, including socioecology, spatial ecology, movement ecology, and conservation biology

Robust velocity dispersion and binary population modeling of the ultra-faint dwarf galaxy Reticulum II

We apply a Bayesian method to model multi-epoch radial velocity measurements in the ultra-faint dwarf galaxy Reticulum II, fully accounting for the effects of binary orbital motion and systematic offsets between different spectroscopic datasets. We find that the binary fraction of Ret II is higher than 0.5 at the 90% confidence level, if the mean orbital period is assumed to be 30 years or longer. Despite this high binary fraction, we infer a best-fit intrinsic dispersion of 2.8$_{-1.2}^{+0.7}$ km/s, which is smaller than previous estimates, but still indicates Ret II is a dark-matter dominated galaxy. We likewise infer a $\lesssim$ 1% probability that Ret II's dispersion is due to binaries rather than dark matter, corresponding to the regime $M_{\odot}/L_{\odot} \lesssim$ 2. Our inference of a high close binary fraction in Ret II echoes previous results for the Segue 1 ultra-faint dwarf and is consistent with studies of Milky Way halo stars that indicate a high close binary fraction tends to exist in metal-poor environments.Comment: 9 pages, 5 figures, to be submitted to MNRA

Astro2020 Science White Paper: Toward Finding Earth 2.0: Masses and Orbits of Small Planets with Extreme Radial Velocity Precision

Having discovered that Earth-sized planets are common, we are now embarking on a journey to determine if Earth-like planets are also common. Finding Earth-like planets is one of the most compelling endeavors of the 21st century - leading us toward finally answering the question: Are we alone? To achieve this forward-looking goal, we must determine the masses of the planets; the sizes of the planets, by themselves, are not sufficient for the determination of the bulk and atmospheric compositions. Masses, coupled with the radii, are crucial constraints on the bulk composition and interior structure of the planets and the composition of their atmospheres, including the search for biosignatures. Precision radial velocity is the most viable technique for providing essential mass and orbit information for spectroscopy of other Earths. The development of high quality precision radial velocity instruments coupled to the building of the large telescope facilities like TMT and GMT or space-based platforms like EarthFinder can enable very high spectral resolution observations with extremely precise radial velocities on minute timescales to allow for the modeling and removal of radial velocity jitter. Over the next decade, the legacy of exoplanet astrophysics can be cemented firmly as part of humankind's quest in finding the next Earth - but only if we can measure the masses and orbits of Earth-sized planets in habitable zone orbits around Sun-like stars.Comment: Science White Paper Submitted to the Astro2020 Decadal Survey (35 co-signers in addition to co-authors

On the Reported Death of the MACHO Era

We present radial velocity measurements of four wide halo binary candidates from the sample in Chaname & Gould (2004; CG04) which, to date, is the only sample containing a large number of such candidates. The four candidates that we have observed have projected separations >0.1 pc, and include the two widest binaries from the sample, with separations of 0.45 and 1.1 pc. We confirm that three of the four CG04 candidates are genuine, including the one with the largest separation. The fourth candidate, however, is spurious at the 5-sigma level. In the light of these measurements we re-examine the implications for MACHO models of the Galactic halo. Our analysis casts doubt on what MACHO constraints can be drawn from the existing sample of wide halo binaries.Comment: 6 Pages, 4 Figures, Accepted for MNRAS Letter

Probable Gravitational Microlensing towards the Galatic Bulge

The MACHO project carries out regular photometric monitoring of millions of stars in the Magellanic Clouds and Galactic Bulge, to search for very rare gravitational microlensing events due to compact objects in the galactic halo and disk. A preliminary analysis of one field in the Galactic Bulge, containing {$\sim430,000$} stars observed for 190 days, reveals four stars which show clear evidence for brightenings which are time-symmetric, achromatic in our two passbands, and have shapes consistent with gravitational microlensing. This is significantly higher than the $\sim 1$ event expected from microlensing by known stars in the disk. If all four events are due to microlensing, a 95\% confidence lower limit on the optical depth towards our bulge field is $1.3 \times 10^{-6}$, and a ``best fit" value is $\tau \approx 1.6 \times 10^{-6}/\epsilon$,where $\epsilon$ is the detection efficiency of the experiment, and $\epsilon < 0.4$. If the true optical depth is close to the ``best fit" value, possible explanations include a ``maximal" disk which accounts for most of the galactic circular velocity at the solar radius, a halo which is centrally concentrated, or bulge-bulge microlensing.Comment: submitted to Astrophysical Journal Letters, 10 pages text as uuencoded compressed PostScript, 5 figures and paper also available via anonymous ftp from merlin.anu.edu.au in /pub/kcf/mach