344 research outputs found
Coral Gardens Reef, Belize: A Refugium in the Face of Caribbean-Wide \u3ci\u3eAcropora\u3c/i\u3e Spp. Coral Decline
Caribbean Acropora spp. corals have undergone a decline in cover since the second half of the twentieth century. Loss of these architecturally complex and fast-growing corals has resulted in significant, cascading changes to the character, diversity, and available eco spaces of Caribbean reefs. Few thriving Acropora spp. populations exist today in the Caribbean and western North Atlantic seas, and our limited ability to access data from reefs assessed via long-term monitoring efforts means that reef scientists are challenged to determine resilience and longevity of existing Acropora spp. reefs. Here we used multiple dating methods to measure reef longevity and determine whether Coral Gardens Reef, Belize, is a refuge for Acropora cervicornis against the backdrop of wider Caribbean decline. We used a new genetic-aging technique to identify sample sites, and radiocarbon and high-precision uranium-thorium (U-Th) dating techniques to test whether one of the largest populations of extant A. cervicornis in the western Caribbean is newly established after the 1980s, or represents a longer-lived, stable population. We did so with respect for ethical sampling of a threatened species. Our data show corals ranging in age from 1910 (14C) or 1915 (230Th) to at least November 2019. While we cannot exclude the possibility of short gaps in the residence of A. cervicornis earlier in the record, the data show consistent and sustained living coral throughout the 1980s and up to at least 2019. We suggest that Coral Gardens has served as a refuge for A. cervicornis and that identifying other, similar sites may be critical to efforts to grow, preserve, conserve, and seed besieged Caribbean reefs
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Predictors of anemia in preschool children: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project.
Background: A lack of information on the etiology of anemia has hampered the design and monitoring of anemia-control efforts.Objective: We aimed to evaluate predictors of anemia in preschool children (PSC) (age range: 6-59 mo) by country and infection-burden category.Design: Cross-sectional data from 16 surveys (n = 29,293) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were analyzed separately and pooled by category of infection burden. We assessed relations between anemia (hemoglobin concentration <110 g/L) and severe anemia (hemoglobin concentration <70 g/L) and individual-level (age, anthropometric measures, micronutrient deficiencies, malaria, and inflammation) and household-level predictors; we also examined the proportion of anemia with concomitant iron deficiency (defined as an inflammation-adjusted ferritin concentration <12 μg/L). Countries were grouped into 4 categories on the basis of risk and burden of infectious disease, and a pooled multivariable logistic regression analysis was conducted for each group.Results: Iron deficiency, malaria, breastfeeding, stunting, underweight, inflammation, low socioeconomic status, and poor sanitation were each associated with anemia in >50% of surveys. Associations between breastfeeding and anemia were attenuated by controlling for child age, which was negatively associated with anemia. The most consistent predictors of severe anemia were malaria, poor sanitation, and underweight. In multivariable pooled models, child age, iron deficiency, and stunting independently predicted anemia and severe anemia. Inflammation was generally associated with anemia in the high- and very high-infection groups but not in the low- and medium-infection groups. In PSC with anemia, 50%, 30%, 55%, and 58% of children had concomitant iron deficiency in low-, medium-, high-, and very high-infection categories, respectively.Conclusions: Although causal inference is limited by cross-sectional survey data, results suggest anemia-control programs should address both iron deficiency and infections. The relative importance of factors that are associated with anemia varies by setting, and thus, country-specific data are needed to guide programs
Improved Photometric Redshifts with Surface Luminosity Priors
We apply Bayesian statistics with prior probabilities of galaxy surface
luminosity (SL) to improve photometric redshifts. We apply the method to a
sample of 1266 galaxies with spectroscopic redshifts in the GOODS North and
South fields at 0.1 < z < 2.0. We start with spectrophotometric redshifts
(SPZs) based on Probing Evolution and Reionization Spectroscopically grism
spectra, which cover a wavelength range of 6000-9000A, combined with
(U)BViz(JHK) broadband photometry in the GOODS fields. The accuracy of SPZ
redshifts is estimated to be \sigma (\Delta(z))=0.035 with an systematic offset
of -0.026, where \Delta(z)=\Delta z / (1+z), for galaxies in redshift range of
0.5 < z < 1.25. The addition of the SL prior probability helps break the
degeneracy of SPZ redshifts between low redshift 4000 A break galaxies and
high-redshift Lyman break galaxies which are mostly catastrophic outliers. For
the 1138 galaxies at z < 1.6, the fraction of galaxies with redshift deviation
\Delta (z) > 0.2 is reduced from 15.0% to 10.4%, while the rms scatter of the
fractional redshift error does not change much.Comment: 7 pages, 7 figures, published in A
The potential of food fortification to add micronutrients in young children and women of reproductive age - findings from a cross-sectional survey in Abidjan, Côte d'Ivoire
Poor micronutrient intakes are a major contributing factor to the high burden of micronutrient deficiencies in Côte d'Ivoire. Large-scale food fortification is considered a cost-effective approach to deliver micronutrients, and fortification of salt (iodine), wheat flour (iron and folic acid), and vegetable oil (vitamin A) is mandatory in Côte d'Ivoire. A cross-sectional survey on households with at least one child 6-23 months was conducted to update coverage figures with adequately fortified food vehicles in Abidjan, the capital of and largest urban community in Côte d'Ivoire, and to evaluate whether additional iron and vitamin A intake is sufficient to bear the potential to reduce micronutrient malnutrition. Information on demographics and food consumption was collected, along with samples of salt and oil. Wheat flour was sampled from bakeries and retailers residing in the selected clusters. In Abidjan, 86% and 97% of salt and vegetable oil samples, respectively, were adequately fortified, while only 32% of wheat flour samples were adequately fortified, but all samples contained some added iron. There were no major differences in additional vitamin A and iron intake between poor and non-poor households. For vitamin A in oil, the additional percentage of the recommended nutrient intake was 27% and 40% for children 6-23 months and women of reproductive age, respectively, while for iron from wheat flour, only 13% and 19% could be covered. Compared to previous estimates, coverage has remained stable for salt and wheat flour, but improved for vegetable oil. Fortification of vegetable oil clearly provides a meaningful additional amount of vitamin A. This is not currently the case for iron, due to the low fortification levels. Iron levels in wheat flour should be increased and monitored, and additional vehicles should be explored to add iron to the Ivorian diet
National Prevalence of Micronutrient Deficiencies, Anaemia, Genetic Blood Disorders and Over- and Undernutrition in Omani Women of Reproductive Age and Preschool Children
A national cross-sectional survey was conducted to estimate the prevalence of anaemia, micronutrient deficiencies, haemoglobin disorders and over- and undernutrition in children and women of reproductive age in Oman. Wasting and stunting were found in 9.3% and 11.4% of children aged 0–59 months, respectively, while 4.2% were overweight or obese. In addition, 23.8% were anaemic and 10.2%, 9.5% and 10.6% had iron, vitamin A and vitamin D deficiencies, respectively. Sickle cell and β-thalassaemia genetic traits were present in 5.3% and 4.2% of children and 4.7% and 2.8% of women, respectively. Overall, 9.1% of Omani women were underweight and 59.2% were overweight or obese. The prevalence of anaemia was 27.8%, while iron, folate, vitamin B12 and vitamin D deficiencies affected 24.8%, 11.6%, 8.9% and 16.2%, respectively. Anaemia among both children and women and the prevalence of overweight and obesity in women are the most concerning nutritional problems in Oman.Keywords: Nutrition Disorders; Malnutrition; Micronutrients; Iron-Deficiency Anemia; Avitaminosis; Vitamin D Deficiency; Vitamin B 12 Deficiency; Oman
On the unification of dwarf and giant elliptical galaxies
The near orthogonal distributions of dwarf elliptical (dE) and giant
elliptical (E) galaxies in the mu_e-Mag and mu_e-log(R_e) diagrams have been
interpreted as evidence for two distinct galaxy formation processes. However,
continuous, linear relationships across the alleged dE/E boundary at M_B = -18
mag - such as those between central surface brightness (mu_0) and (i) galaxy
magnitude and (ii) light-profile shape (n) - suggest a similar, governing
formation mechanism. Here we explain how these latter two linear trends
necessitate a different behavior for dE and E galaxies, exactly as observed, in
diagrams involving mu_e (and also _e). A natural consequence is that the
distribution of dEs and Es in Fundamental Plane type analyses that use the
associated intensity I_e, or _e, are expected to appear different. Together
with other linear trends across the alleged dE/E boundary, such as those
between luminosity and color, metallicity, and velocity dispersion, it appears
that the dEs form a continuous extension to the E galaxies. The presence of
partially depleted cores in luminous (M_B < -20.5 mag) Es does however signify
the action of a different physical process at the centers (< ~300 pc) of these
galaxies.Comment: 5 pages from the proceedings of the 2004 conference "Penetrating bars
through masks of cosmic dust: the Hubble tuning fork strikes a new note".
Edited by D. L. Block, I. Puerari, K. C. Freeman, R. Groess, and E. K. Bloc
Effectiveness of an integrated agriculture, nutrition-specific, and nutrition-sensitive program on child growth in Western Kenya: a cluster-randomized controlled trial
Background: Stunting rates remain unacceptably high in many regions, including sub-Saharan Africa. Agricultural programs have led to increased yields and household incomes but showed limited success in improving nutritional status.
Objectives: We assessed whether linear growth could be improved through a potentially scalable, integrated program adding nutrition-specific and nutrition-sensitive components to an existing agricultural program.
Methods: In this cluster-randomized controlled trial in rural Western Kenya, we randomized children aged 6–35 months from farming families to an agricultural intervention without (control group) or with a bundle of interventions (intervention group), including distribution of micronutrient powders (MNP), poultry to increase egg consumption, seeds of greens and onions, and soap and chlorine solution, as well as provision of monthly behavior change trainings. The primary outcome was the change in height-for-age z-score (HAZ) over 2 years of follow-up. We assessed safety through active morbidity and passive adverse event monitoring. We conducted an intention-to-treat analysis, followed by per-protocol and prespecified subgroup analyses.
Results: From March to April 2018, we enrolled 1927 children from 126 clusters (control, 942 children in 63 clusters; intervention, 985 children in 63 clusters). Data on HAZ were available for 1672 (86.6%) children after 2 years. Adherence was >80% for use of MNP, chlorine, and greens and receipt of soap, and ∼40% for egg and red onion consumption. The intention-to-treat analysis indicated a greater change in HAZ over 2 years in the intervention group (adjusted effect size, 0.11; 95% CI: 0.02–0.19). We found a slightly stronger effect in the per-protocol analysis (adjusted effect size, 0.15; 95% CI: 0.06–0.24). Dietary diversity and consumption of iron-rich foods were improved in the intervention group, and reported instances of fever, lower respiratory tract infections, and diarrheal episodes were lower in the intervention group.
Conclusions: This study found a modest improvement in linear growth, indicating the need for multiple, integrated interventions to achieve benefits. The trial was registered with clinicaltrials.gov as NCT03448484
Molecular Gas in the z=1.2 Ultraluminous Merger GOODS J123634.53+621241.3
We report the detection of CO(2-1) emission from the z=1.2 ultraluminous
infrared galaxy (ULIRG) GOODS J123634.53+621241.3 (also known as the
sub-millimeter galaxy GN26). These observations represent the first discovery
of high-redshift CO emission using the new Combined Array for Research in
Millimeter-Wave Astronomy (CARMA). Of all high-redshift (z>1) galaxies within
the GOODS-North field, this source has the largest far-infrared (FIR) flux
observed in the Spitzer 70um and 160um bands. The CO redshift confirms the
optical identification of the source, and the bright CO(2-1) line suggests the
presence of a large molecular gas reservoir of about 7x10^10 M(sun). The
infrared-to-CO luminosity ratio of L(IR)/L'(CO) = 80+/-30 L(sun) (K Km/s
pc^2)^-1 is slightly smaller than the average ratio found in local ULIRGs and
high-redshift sub-millimeter galaxies. The short star-formation time scale of
about 70 Myr is consistent with a starburst associated with the merger event
and is much shorter than the time scales for spiral galaxies and estimates made
for high-redshift galaxies selected on the basis of their B-z and z-K colors.Comment: Accepted for publication in ApJ Letter
Early-type galaxies in the PEARS survey: Probing the stellar populations at moderate redshift
Using HST/ACS slitless grism spectra from the PEARS program, we study the
stellar populations of morphologically selected early-type galaxies in the
GOODS North and South fields. The sample - extracted from a visual
classification of the (v2.0) HST/ACS images and restricted to redshifts z>0.4 -
comprises 228 galaxies (F775W<24 ABmag) out to z~1.3 over 320 arcmin2, with a
median redshift zM=0.75. This work significantly increases our previous sample
from the GRAPES survey in the HUDF (18 galaxies over ~11 arcmin2; Pasquali et
al. 2006b). The grism data allow us to separate the sample into `red' and
`blue' spectra, with the latter comprising 15% of the total. Three different
grids of models parameterising the star formation history are used to fit the
low-resolution spectra. Over the redshift range of the sample - corresponding
to a cosmic age between 5 and 10 Gyr - we find a strong correlation between
stellar mass and average age, whereas the **spread** of ages (defined by the
RMS of the distribution) is roughly ~1 Gyr and independent of stellar mass. The
best-fit parameters suggest it is formation epoch and not formation timescale,
that best correlates with mass in early-type galaxies. This result - along with
the recently observed lack of evolution of the number density of massive
galaxies - motivates the need for a channel of (massive) galaxy formation
bypassing any phase in the blue cloud, as suggested by the simulations of Dekel
et al. (2009).Comment: 12 pages, 12 figures, 3 tables. Submitted for publication in Ap
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