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A Miniature Thermal Emission Spectrometer (Mini-TES), based on a Michelson interferometer and Cassegrain telescope, was carried by the Spirit rover in Gusev crater and Opportunity rover at Meridiani Planum to determine the bulk mineralogy of surface materials. Spectra from the plains of Gusev demonstrate the ubiquity of olivine-rich basaltic rocks, with additional examples lofted into the adjacent Columbia Hills by meteoroid impacts. Hundreds of rocks observed with mini-TES in the Columbia Hills display spectral characteristics of variable alteration intensity, but likely with very little water involved. Rare exceptions include a tephra deposit cemented by Mg–Fe carbonates and nodular opaline silica rocks, likely indicative of a hot spring/geyser environment. Opportunity’s mini-TES confirmed orbital identification of crystalline hematite at Meridiani Planum and spectral characteristics indicative of a transition from a precursor goethite phase. The sedimentary bedrock that hosts the hematite has spectral features consistent with Al-rich opaline silica, Mg-, Ca-, and Fe-bearing sulfates, plagioclase feldspar, and nontronite. Rare rocks at both sites are recognizable as iron meteorites from their infrared reflective properties.
Thermal infrared data collected by the Thermal Emission Spectrometer (TES) and Thermal Emission Imaging System (THEMIS) instruments have significantly impacted the understanding of martian surface mineralogy. Spatial/temporal variations in igneous lithologies; the discovery of quartz, carbonates, and chlorides; and the widespread identification of amorphous, silica-enriched materials reveal a planet that has experienced a diversity of primary and secondary geo-logic processes including igneous crustal evolution, regional sedimentation, aqueous alteration, and glacial/periglacial activity.
Malnutrition remains a leading contributor to the morbidity and mortality of children under the age of 5 years and can weaken the immune system and increase the severity of concurrent infections. Livestock milk with the protective properties of human milk is a potential therapeutic to modulate intestinal microbiota and improve outcomes. The aim of this study was to develop an infection model of childhood malnutrition in the pig to investigate the clinical, intestinal and microbiota changes associated with malnutrition and enterotoxigenic Escherichia coli (ETEC) infection and to test the ability of goat milk and milk from genetically engineered goats expressing the antimicrobial human lysozyme (hLZ) milk to mitigate these effects. Pigs were weaned onto a protein–energy-restricted diet and after 3 weeks were supplemented daily with goat, hLZ or no milk for a further 2 weeks and then challenged with ETEC. The restricted diet enriched faecal microbiota in Proteobacteria as seen in stunted children. Before infection, hLZ milk supplementation improved barrier function and villous height to a greater extent than goat milk. Both goat and hLZ milk enriched for taxa (Ruminococcaceae) associated with weight gain. Post-ETEC infection, pigs supplemented with hLZ milk weighed more, had improved Z-scores, longer villi and showed more stable bacterial populations during ETEC challenge than both the goat and no milk groups. This model of childhood disease was developed to test the confounding effects of malnutrition and infection and demonstrated the potential use of hLZ goat milk to mitigate the impacts of malnutrition and infection.
OBJECTIVES/SPECIFIC AIMS: The overall goal of this project is to enhance the use of GCRA in Latina breast cancer survivors at high risk of hereditary breast and ovarian cancer to reduce disparities in GCRA uptake. The aims of the study are to (1) develop a cultural adaptation of an evidence-based TGC intervention that consists of phone genetic counseling and a booklet, (2) evaluate the impact of TGC Versus Usual Care, and (3) explore the communication patterns in TGC and genetic counseling sessions with an interpreter. METHODS/STUDY POPULATION: We are conducting a 2-phase, mixed methods study. In Phase I we will develop a cultural adaption of an evidence-based intervention (TGC) for high-risk Latina breast cancer survivors using the Learner Verification and Revision Framework (n=15). In Phase II we will use a cluster randomized design with four community sites randomized to Spanish TGC (n=2 sites) or usual care (n=2 sites) (n=60; 15 per site). The primary outcome is genetic counseling uptake. Among women who receive genetic counseling either through TGC (n~30) or with an interpreter (n~15), we will assess counseling quality by reviewing 20 randomly selected audiotaped sessions (10 TGC; 10 interpreters). We will evaluate women’s HBOC knowledge and satisfaction with counseling. Communication processes and outcomes will be assessed using gold standard RIAS quantitative coding system and qualitative discourse analysis. RESULTS/ANTICIPATED RESULTS: We elicited input from transdisciplinary team members to develop an initial adaptation of a TGC print booklet and intervention protocol for use with high-risk Latina breast cancer survivors with limited English proficiency. The booklet contains low-literacy information about HBOC, risk factors, pros and cons of testing, and management strategies. Based on these materials and prior work, we anticipate TGC will consist of one 1 hour or less TGC session by phone. Participants interested in pursuing testing will receive a saliva kit and will participate in a second TGC session (30 min) to discuss test results and management options. DISCUSSION/SIGNIFICANCE OF IMPACT: Given access barriers and the shortage of Spanish-speaking genetic counselors, adapting and translating TGC intervention is a promising strategy that could reduce disparities by broadening the reach and accessibility to genetic counseling while enhancing the quality of the service for Latinas with limited English proficiency.
Six streams of dust were unexpectedly detected by the Ulysses dust detector while this spacecraft was approximately within one AU distance from Jupiter (Grün et al., 1993). Stream durations ranged from hours to days for individual streams. It was clear that the dust in these streams (or bursts), from their directionality of approach to the spacecraft and from the nearness of stream occurrences to Jupiter, emanated from the Jovian system.
Following the original report, Baguhl et al. (1994) later relaxed the criteria for differentiating true dust impacts from “noise pulses” and found almost triple the number of dust impacts in the six streams already found. They also found 5 more streams that, except for one stream, clearly emanated from the Jovian system. The criteria were relaxed in such a way as to not introduce “noise events” into the data.
The decision to utilize antimicrobials in end-of-life situations is complex. Understanding the reasons why physicians prescribe antimicrobials in this patient population is important for informing the design of antimicrobial stewardship interventions.
A 51-item survey containing both closed and open-ended questions on end-of-life antimicrobial use was administered to physicians affiliated with the University of Pennsylvania and Children’s Hospital of Philadelphia from January through April 2017. A mixed-methods approach was used to analyze responses.
Of 637 physicians surveyed, 283 responses (44.4%) were received. Most (86.2%) physicians believed that respecting a patient’s wish to continue antimicrobials was important. Approximately half of physicians (49.8%) believed that antimicrobial use at the end of life contributes to resistance. A higher proportion of pediatricians would often or always continue antimicrobial treatment for active infections and for hospice patients whose death was imminent compared to adult physicians (P<.001). Analysis of free-text responses revealed additional reasons why physicians may continue antimicrobials at end of life, including meeting family expectations, wanting to avoid the perception of “giving up,” uncertainty about prognosis, and reducing patient pain or discomfort.
Physician decision making concerning antimicrobial use in patients at the end of life is multifactorial. Clinicians may overweigh the benefits of antimicrobial therapy in end-of-life situations and view the importance of adhering to stewardship policies differently. Pediatric and adult clinicians have different approaches to this patient population. Better understanding of the complex decision making that occurs in the end-of-life patient population can help guide antimicrobial stewardship policies and improve patient care.
Collagen associated with bone samples is frequently used for radiocarbon (14C) dating of bones recovered from archaeological sites. However, submersion and exposure to moisture favors the degradation of collagen, which leads to difficulty in reliably dating bones from tropical, humid, or previously submerged archaeological sites. In this paper, we characterized the preservation state of a series of bones, through parameters such as %C, %N, C/N ratio, and collagen recovery. We performed 14C analyses of three collagen fractions obtained through the pretreatment steps (total, ultrafiltered, and insoluble collagen) in order to link the preservation state and the reproducibility of 14C values obtained from the three fractions. Collagen ultrafiltration resulted in a decrease of C/N ratio, although collagen yield was reduced. When two or three collagen fractions were obtained, ages were reproducible and consistent with expected values, according to archaeological or hydrogeological criteria. The pretreatment steps were monitored by infrared spectroscopy in order to analyze the collagen fractions at the molecular level. The presence of collagen in the total and insoluble fractions was confirmed. Since many of the Mexican samples had poor ultrafiltered collagen yield (<3%) or nonexistent yield, our results show that if additional contextual information is carefully considered, the remnant collagen in the total and insoluble fraction can be dated, especially from sites where no other datable fraction exists.
The Nevado de Toluca is a stratovolcano located in the southwest of the Toluca Valley in central Mexico. At a height of around 4200 m there are two crater lakes: El Sol and La Luna. Since Precolumbian times, people in the surrounding valleys carried out rituals and deposited offerings into the lakes. After the Spanish conquest, these rituals were kept alive clandestinely. Currently, reminiscent of Mesoamerican rituals subsist. Due to the long duration of the ritual at the Nevado de Toluca, it is important to date the materials recovered in the underwater and terrestrial archaeological explorations. This article proposes a chronology of Prehispanic ritual activities performed in the Nevado de Toluca based on the characterization and radiocarbon (14C) dating performed to materials from the volcano’s lakes.
This article focuses on radiocarbon (14C) dating of the organic matter (OM) of natural-anthropogenic objects—the cultural layers (CLs) of archaeological sites. Using examples from three ancient sites located within the European part of Russia, in southern taiga and forest-steppe natural zones, we demonstrate approaches to the interpretation of 14C dating of OM derived from the organomineral material of the CLs studied. We use the term “archaeological humus” as defined as the OM formed within the CL from “anthropogenic matter” (i.e., organic residues that were produced during the past human occupation of the site) without or with negligible contribution of OM inherited from pre-anthropogenic stages of pedogenesis. The archaeological humus is formed within closed or semi-closed systems by the processes of humification and physical stabilization of OM. The use of hierarchical (from macro- to submicro-) morphological investigations at one of the sites (Gnezdovo) combined with 14C dating allowed conclusions to be drawn about the age of formation of different OM components in CLs.
In this paper, first results comparing modified Longin and ninhydrin collagen extraction methodologies are presented. The goal of this study is to investigate the bones of several species with different ages, preservation conditions, and collagen contents to determine the most suitable preparation method. Different types of samples are used such as VIRI samples, previously dated bones, and background samples. Each bone has undergone elemental analysis, infrared analysis, and 14C measurement. The results are presented and the advantages and disadvantages of each preparation method are discussed. In general, results obtained by the two methods are in accordance with the consensus value for 2σ uncertainty. For VIRI I and a mammoth bone, the ninhydrin preparation gives, respectively, 8450±70 BP and 14,870±60 BP whereas the modified Longin process gives 8365±45 BP and 14,750±100 BP in agreement with the expected values. From the experimental point of view, the modified Longin process is easier to implement than the ninhydrin protocol. From this approach, we can conclude that the modified Longin process could be preferred in most cases and particularly when the amount of bone is small and the sample is not too contaminated.
After decades of collaborative experience between archaeologists and radiocarbon scientists, with the aim at producing radiocarbon dates capable of answering the most various research questions, it is now widely recognized that an accurate sampling strategy is the cornerstone of a solid 14C-based chronology. In this paper, we discuss the sampling criteria required to obtain good quality 14C data within a challenging archaeological context like the Bronze Age site of Erimi Laonin tou Porakou (Limassol, Cyprus). Following a dedicated sampling strategy, in the productive complex of the settlement, charcoal samples were collected from secure contexts according to stratigraphic examination of excavated strata and analysis of associated features and material culture. Micromorphology was also applied for a more accurate interpretation of individual deposits and reconstruction of depositional and post-depositional processes. In the necropolis, bone samples were selected among the fragmentary and commingled human remains through evaluation of the preservation state and the minimum number of individuals (MNI). A discrepancy between the charcoal and the bone 14C determinations was encountered, probably due to old wood issues. The 14C dates were analyzed using a Bayesian model that incorporates the archaeological information, and a preliminary 14C-based chronology was defined for this site.
Interest in planting mixtures of cover crop species has grown in recent years as farmers seek to increase the breadth of ecosystem services cover crops provide. As part of a multidisciplinary project, we quantified the degree to which monocultures and mixtures of cover crops suppress weeds during the fall-to-spring cover crop growing period. Weed-suppressive cover crop stands can limit weed seed rain from summer- and winter-annual species, reducing weed population growth and ultimately weed pressure in future cash crop stands. We established monocultures and mixtures of two legumes (medium red clover and Austrian winter pea), two grasses (cereal rye and oats), and two brassicas (forage radish and canola) in a long fall growing window following winter wheat harvest and in a shorter window following silage corn harvest. In fall of the long window, grass cover crops and mixtures were the most weed suppressive, whereas legume cover crops were the least weed suppressive. All mixtures also effectively suppressed weeds. This was likely primarily due to the presence of fast-growing grass species, which were effective even when they were seeded at only 20% of their monoculture rate. In spring, weed biomass was low in all treatments due to winter kill of summer-annual weeds and low germination of winter annuals. In the short window following silage corn, biomass accumulation by cover crops and weeds in the fall was more than an order of magnitude lower than in the longer window. However, there was substantial weed seed production in the spring in all treatments not containing cereal rye (monoculture or mixture). Our results suggest that cover crop mixtures require only low seeding rates of aggressive grass species to provide weed suppression. This creates an opportunity for other species to deliver additional ecosystem services, though careful species selection may be required to maintain mixture diversity and avoid dominance of winter-hardy cover crop grasses in the spring.
An updated compilation of published and new data of major-ion (Ca, Cl, K, Mg, Na, NO3, SO4) and methylsulfonate (MS) concentrations in snow from 520 Antarctic sites is provided by the national ITASE (International Trans-Antarctic Scientific Expedition) programmes of Australia, Brazil, China, Germany, Italy, Japan, Korea, New Zealand, Norway, the United Kingdom, the United States and the national Antarctic programme of Finland. The comparison shows that snow chemistry concentrations vary by up to four orders of magnitude across Antarctica and exhibit distinct geographical patterns. The Antarctic-wide comparison of glaciochemical records provides a unique opportunity to improve our understanding of the fundamental factors that ultimately control the chemistry of snow or ice samples. This paper aims to initiate data compilation and administration in order to provide a framework for facilitation of Antarctic-wide snow chemistry discussions across all ITASE nations and other contributing groups. The data are made available through the ITASE web page (http://www2.umaine.edu/itase/content/syngroups/snowchem.html) and will be updated with new data as they are provided. In addition, recommendations for future research efforts are summarized.
Bone is frequently dated in archaeological studies and, especially for very old bones (more than 40,000 years old), it is critical to have an accurate and precise measure of the material-specific background value and its associated uncertainty. The SUERC Radiocarbon Laboratory has obtained a mammoth bone as a background bone standard and an appropriate number are now routinely prepared and measured in each AMS batch, resulting in the accumulation of a large number of background bone results over a two-year period. Additionally, information on which of the two accelerator mass spectrometry (AMS) instruments was used to make the radiocarbon (14C) measurements, and which sample pretreatment method (modified Longin or modified ultrafiltration) was used to extract and purify the collagen, is recorded for each sample. These data have been used to estimate the laboratory bone background (to be subtracted from each unknown bone sample prepared in the laboratory) and its associated analytical uncertainty. The statistical analysis of the bone results has made use of a linear mixed effects model to examine the variation, and to apportion the overall variation between and within batches on both AMS instruments, and the different pretreatment methods used at SUERC.
We present a new surface-balance and ice-motion dataset derived from high-precision GPS measurements from a network of steel poles within three icefields of the Allan Hills blue-ice area, Antarctica. The surveys were conducted over a 14 year time period. Ice-flow velocities and mass- balance estimates for the main icefield (MIF) are consistent with those from pre-GPS era measurements but have much smaller uncertainties. The current study also extends these measurements through the near-western icefield (NWIF) to the eastern edge of the mid-western icefield (MWIF). The new dataset includes, for the first time, well-constrained evidence of upward motion within the Allan Hills MIF, indicating that old ice should be present at the surface. These data and terrestrial meteorite ages suggest that paleoclimate reconstructions using the surface record within the Allan Hills MIF could potentially extend the ice-core-based record beyond the 800 000 years currently available in the EPICA Dome C core.
The SUERC Radiocarbon Laboratory employs a one-step “background subtraction” method when calculating 14C ages. An interglacial wood (VIRI Sample K) is employed as the non-bone organic background standard, while a mammoth bone (LQH12) from Latton Quarry is used as the bone background standard. Results over several years demonstrate that the bone background is consistently around a factor of two higher and more variable than the wood background. As a result, the uncertainty on routine bone measurements is higher than for other sample types. This study investigates the factors that may contribute to the difference in F14C values and the higher variability. Preparations of collagen using modified Longin or ultrafiltration methods show no significant difference, nor does eliminating the collagen dissolution step. Two bone samples of known infinite age with respect to radiocarbon are compared and again no significant difference is observed. Finally, the quantity and age of the organic matter in the water used during the pretreatment is investigated and it is shown that there is insufficient organic matter in the reverse osmosis water to influence background values significantly. The attention is now on determining if incomplete demineralization could lead to contaminants being retained by the phosphate in the hydroxyapatite.
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.