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Bayesian analysis of radiocarbon (14C) dates in North American archaeology is increasing, especially among archaeologists working in deeper time. However, historical archaeologists have been slow to embrace these new techniques, and there have been only a few examples of the incorporation of calendar dates as informative priors in Bayesian models in such work in the United States. To illustrate the value of Bayesian approaches to sites with both substantial earlier Native American occupations as well as a historic era European presence, we present the results of our Bayesian analysis of 14C dates from the earlier Guale village and the Mission period contexts from the Sapelo Shell Ring Complex (9MC23) in southern Georgia. Jefferies and Moore have explored the Spanish Mission period deposits at this site to better understand the Native American interactions with the Spanish during the 16th and 17th centuries along the Georgia Coast. Given the results of our Bayesian modeling, we can say with some degree of confidence that the deposits thus far excavated and sampled contain important information dating to the 17th-century mission on Sapelo Island. In addition, our modeling of new dates suggests the range of the pre-Mission era Guale village. Based on these new dates, we can now say with some degree of certainty which of the deposits sampled likely contain information that dates to one of the critical periods of Mission period research, the AD 1660–1684 period that ushered in the close of mission efforts on the Georgia Coast.
Farmers’ access to reliable information is crucial to improving rural livelihoods, food security, and national economies in West Africa. This paper discusses the dynamics of accessing and using agricultural learning videos from commercial channels, vs project and non-project channels in Benin and Mali. Using combinations of different models to assess the effectiveness of agricultural extension programs, the findings showed that farmers were motivated to pay for videos and watch them by themselves, without facilitation. Farmers who watched the videos through project support have also continued to watch on their own if the videos are of interest to them. Nevertheless, farmers were less motivated in the learning process when they received the Digital Video Disc (DVD) free and without support to watch them. We also found that the distribution of learning videos through commercial channels reaches more serious users and increases farmers’ self-determination for learning, and farmers are more motivated to provide feedback than viewers who receive DVDs for free or via project support, Non-Governmental Organizations (NGOs), or farmer organizations. Although buying a DVD is an individual action, they like to watch the videos in groups. After buying the DVD, about 43% of respondent borrowed DVD players and one person in five bought a DVD player to watch the videos. Efforts to promote improved technologies need to expand beyond the conventional focus on research and extension services. Support to agricultural technology dissemination must go beyond assistance to smallholder farmers and NGOs (practical implication). As the private sector has a role to play, both in making technologies available and in teaching farmers how to use them, their contribution would create space for innovation (theoretical implication). Our findings suggest that successful development intervention programs can be sell audiovisual material to farmers, who will use it proactively.
Registry-based trials have emerged as a potentially cost-saving study methodology. Early estimates of cost savings, however, conflated the benefits associated with registry utilisation and those associated with other aspects of pragmatic trial designs, which might not all be as broadly applicable. In this study, we sought to build a practical tool that investigators could use across disciplines to estimate the ranges of potential cost differences associated with implementing registry-based trials versus standard clinical trials.
We built simulation Markov models to compare unique costs associated with data acquisition, cleaning, and linkage under a registry-based trial design versus a standard clinical trial. We conducted one-way, two-way, and probabilistic sensitivity analyses, varying study characteristics over broad ranges, to determine thresholds at which investigators might optimally select each trial design.
Registry-based trials were more cost effective than standard clinical trials 98.6% of the time. Data-related cost savings ranged from $4300 to $600,000 with variation in study characteristics. Cost differences were most reactive to the number of patients in a study, the number of data elements per patient available in a registry, and the speed with which research coordinators could manually abstract data. Registry incorporation resulted in cost savings when as few as 3768 independent data elements were available and when manual data abstraction took as little as 3.4 seconds per data field.
Registries offer important resources for investigators. When available, their broad incorporation may help the scientific community reduce the costs of clinical investigation. We offer here a practical tool for investigators to assess potential costs savings.
Photoreceptors have high energy demands and densely packed mitochondria through which light passes before phototransduction. Old world primates including humans have three cone photoreceptor types mediating color vision with short (S blue), medium (M green), and long (L red) wavelength sensitivities. However, S-cones are enigmatic. They comprise <10% of the total cone population, their responses saturate early, and they are susceptible in aging and disease. Here, we show that primate S-cones actually have few mitochondria and are fueled by glycolysis, not by mitochondrial respiration. Glycolysis has a limited ability to sustain activity, potentially explaining early S-cone saturation. Mitochondria act as optical filters showing reduced light transmission at 400–450 nm where S-cones are most sensitive (420 nm). This absorbance is likely to arise in a mitochondrial porphyrin that absorbs strongly in the Soret band. Hence, reducing mitochondria will improve S-cone sensitivity but result in increased glycolysis as an alternative energy source, potentially increasing diabetic vulnerability due to restricted glucose access. Further, glycolysis carries a price resulting in premature functional decline as seen in aged S-cones. Soret band absorption may also impact on mitochondrial rich M and L cones by reducing sensitivity at the lower end of their spectral sensitivity range resulting in increased differentiation from S-cone responses. These data add to the list of unique characteristic of S-cones and may also explain aspects of their vulnerability.
The Single Ventricle Reconstruction trial randomised neonates with hypoplastic left heart syndrome to a systemic-to-pulmonary-artery shunt strategy. Patients received care according to usual institutional practice. We analysed practice variation at the Stage II surgery to attempt to identify areas for decreased variation and process control improvement.
Prospectively collected data were available in the Single Ventricle Reconstruction public-use database. Practice variation across 14 centres was described for 397 patients who underwent Stage II surgery. Data are centre-level specific and reported as interquartile ranges across all centres, unless otherwise specified.
Preoperative Stage II median age and weight across centres were 5.4 months (interquartile range 4.9–5.7) and 5.7 kg (5.5–6.1), with 70% performed electively. Most patients had pre-Stage-II cardiac catheterisation (98.5–100%). Digoxin was used by 11/14 centres in 25% of patients (23–31%), and 81% had some oral feeds (68–84%). The majority of the centres (86%) performed a bidirectional Glenn versus hemi-Fontan. Median cardiopulmonary bypass time was 96 minutes (75–113). In aggregate, 26% of patients had deep hypothermic circulatory arrest >10 minutes. In 13/14 centres using deep hypothermic circulatory arrest, 12.5% of patients exceeded 10 minutes (8–32%). Seven centres extubated 5% of patients (2–40) in the operating room. Postoperatively, ICU length of stay was 4.8 days (4.0–5.3) and total length of stay was 7.5 days (6–10).
In the Single Ventricle Reconstruction Trial, practice varied widely among centres for nearly all perioperative factors surrounding Stage II. Further analysis may facilitate establishing best practices by identifying the impact of practice variation.
OBJECTIVES/SPECIFIC AIMS: Rodent models can be used to study neonatal abstinence syndrome (NAS), but the applicability of findings from the models to NAS in humans is not well understood. The objective of this study was to develop a rat model of norbuprenorphine-induced NAS and validate its translational value by comparing blood concentrations in the norbuprenorphine-treated pregnant rat to those previously reported in pregnant women undergoing buprenorphine treatment. METHODS/STUDY POPULATION: Pregnant Long-Evans rats were implanted with 14-day osmotic minipumps containing vehicle, morphine (positive control), or norbuprenorphine (0.3–3 mg/kg/d) on gestation day 9. Within 12 hours of delivery, pups were tested for spontaneous or precipitated opioid withdrawal by injecting them with saline (10 mL/kg, i.p.) or naltrexone (1 or 10 mg/kg, i.p), respectively, and observing them for well-validated neonatal withdrawal signs. Blood was sampled via indwelling jugular catheters from a subset of norbuprenorphine-treated dams on gestation day 8, 10, 13, 17, and 20. Norbuprenorphine concentrations in whole blood samples were quantified using LC/MS/MS. RESULTS/ANTICIPATED RESULTS: Blood concentrations of norbuprenorphine in rats exposed to 1–3 mg/kg/d of norbuprenorphine were similar to levels previously reported in pregnant women undergoing buprenorphine treatment. Pups born to dams treated with these doses exhibited robust withdrawal signs. Blood concentrations of norbuprenorphine decreased across gestation, which is similar to previous reports in humans. DISCUSSION/SIGNIFICANCE OF IMPACT: These results suggest that dosing dams with 1–3 mg/kg/day norbuprenorphine produces maternal blood concentrations and withdrawal severity similar to those previously reported in humans. This provides evidence that, at these doses, this model is useful for testing hypotheses about norbuprenorphine that are applicable to NAS in humans.
Glacier basal motion generates diurnal to multi-annual fluctuations in glacier velocity and mass flux. Understanding these fluctuations is important for prediction of future sea-level rise and for gaining insight into glacier physics and erosion. Here, we derive glacier velocity through cross-correlation of WorldView satellite imagery to document the evolution of ice surface velocity on Kennicott Glacier, Alaska, over the 2013 melt season. The summer speedup is spatially uniform over a ~12 km2 area, over which the spring velocity varies significantly. Velocity increases by 1.4-fold to tenfold across the study domain, with larger values where spring velocities are low. To investigate the cross-glacier distribution of basal motion required to explain the observed surface speedup, we employ a two-dimensional cross-sectional glacier flow model. We find the model is insensitive to the spatial distribution of basal slip because stress gradient ice coupling diffuses the surface expression of the basal velocity field. While the temporal evolution of the subglacial hydrologic system is critical for predicting a glacier's response to meltwater inputs, our work suggests that glacier and ice-sheet models do not require a detailed representation of subglacial hydrology to accurately capture the spatial pattern of glacier speedup.
Analyzing historical trajectories of social interactions at varying scales can lead to complementary interpretations of relationships among archaeological settlements. We use social network analysis combined with geographic information systems at three spatial scales over time in the western U.S. Southwest to show how the same social processes affected network dynamics at each scale. The period we address, A.D. 1200–1450, was characterized by migration and demographic upheaval. The tumultuous late thirteenth-century interval was followed by population coalescence and the development of widespread religious movements in the fourteenth and fifteenth centuries. In the southern Southwest these processes resulted in a highly connected network that drew in members of different settlements within and between different valleys that had previously been distinct. In the northern Southwest networks were initially highly connected followed by a more fragmented social landscape. We examine how different network textures emerged at each scale through 50-year snapshots. The results demonstrate the usefulness of applying a multiscalar approach to complex historical trajectories and the potential for social network analysis as applied to archaeological data.
While it is widely believed that a “conservative coalition” of Southern Democrats and Republicans sometimes formed on floor votes in the mid-twentieth-century House to block liberal policy initiatives, a fully fleshed-out picture of what the coalition was and how it operated is lacking. In this article, we investigate whether the conservative coalition wielded negative agenda control, that is, whether it used positions of power in the House to block bills from floor consideration that would have harmed a majority of its members. We find that the likelihood that the conservative coalition was rolled increased significantly after the Rules Committee packing in 1961—especially for bills that came from standing committees chaired by nonsoutherners. These results are consistent with the notion that Rules systematically protected the conservative coalition from unfavorable floor votes and that southern committee chairs continued to offer some blocking power after the Rules packing.
To investigate factors (ability, motivation and the environment) that act as barriers to limiting fast-food consumption in women who live in an environment that is supportive of poor eating habits.
Cross-sectional study using self-reports of individual-level data and objectively measured environmental data. Multilevel logistic regression was used to assess factors associated with frequency of fast-food consumption.
Socio-economically disadvantaged areas in metropolitan Melbourne, Australia.
Women (n 932) from thirty-two socio-economically disadvantaged neighbourhoods living within 3 km of six or more fast-food restaurants. Women were randomly sampled in 2007–2008 as part of baseline data collection for the Resilience for Eating and Activity Despite Inequality (READI) study.
Consuming low amounts of fast food was less likely in women with lower perceived ability to shop for and cook healthy foods, lower frequency of family dining, lower family support for healthy eating, more women acquaintances who eat fast food regularly and who lived further from the nearest supermarket. When modelled with the other significant factors, a lower perceived shopping ability, mid levels of family support and living further from the nearest supermarket remained significant. Among those who did not perceive fruits and vegetables to be of high quality, less frequent fast-food consumption was further reduced for those with the lowest confidence in their shopping ability.
Interventions designed to improve women's ability and opportunities to shop for healthy foods may be of value in making those who live in high-risk environments better able to eat healthily.
Nutrition label use could help consumers eat healthfully. Despite consumers reporting label use, diets are not very healthful and obesity rates continue to rise. The present study investigated whether self-reported label use matches objectively measured label viewing by monitoring the gaze of individuals viewing labels.
The present study monitored adults viewing sixty-four food items on a computer equipped with an eye-tracking camera as they made simulated food purchasing decisions. ANOVA and t tests were used to compare label viewing across various subgroups (e.g. normal weight v. overweight v. obese; married v. unmarried) and also across various types of foods (e.g. snacks v. fruits and vegetables).
Participants came to the University of Minnesota's Epidemiology Clinical Research Center in spring 2010.
The 203 participants were ⩾18 years old and capable of reading English words on a computer 76 cm (30 in) away.
Participants looked longer at labels for ‘meal’ items like pizza, soup and yoghurt compared with fruits and vegetables, snack items like crackers and nuts, and dessert items like ice cream and cookies. Participants spent longer looking at labels for foods they decided to purchase compared with foods they decided not to purchase. There were few between-group differences in nutrition label viewing across sex, race, age, BMI, marital status, income or educational attainment.
Nutrition label viewing is related to food purchasing, and labels are viewed more when a food's healthfulness is ambiguous. Objectively measuring nutrition label viewing provides new insight into label use by various sociodemographic groups.