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The development of Middle Preclassic (900–300 BC) ceremonial architecture is receiving more attention by archaeologists conducting research in the Maya Lowlands. Although a few examples have been partially excavated, there is still a dearth of information on how and why monumental constructions were originally built. This is largely because early structures often lie below several layers of sequential architecture, making them difficult to locate. Even when Middle Preclassic architecture is identified, exposure is often too limited to fully investigate its form and function. A well-preserved and accessible Middle Preclassic platform would be a rare find and could greatly enhance our knowledge and understanding of the subject. At Pacbitun, Cayo District, Belize, such a discovery has been made beneath the artificially raised surface of the main plaza. To make the most of this opportunity, five seasons of excavation worked to expose this massive building in its entirety. In this article, we provide details concerning the structural design of the platform and its abandonment, as well as present potential architectural comparisons. We conclude by reevaluating complexity at Pacbitun.
The illegal wildlife trade is driving declines in populations of a number of large, charismatic animal species but also many lesser known and restricted-range species, some of which are now facing extinction as a result. The ploughshare tortoise Astrochelys yniphora, endemic to the Baly Bay National Park of north-western Madagascar, is affected by poaching for the international illegal pet trade. To quantify this, we estimated population trends during 2006–2015, using distance sampling surveys along line transects, and recorded national and international confiscations of trafficked tortoises for 2002–2016. The results suggest the ploughshare tortoise population declined > 50% during this period, to c. 500 adults and subadults in 2014–2015. Prior to 2006 very few tortoises were seized either in Madagascar or internationally but confiscations increased sharply from 2010. Since 2015 poaching has intensified, with field reports suggesting that two of the four subpopulations are extinct, leaving an unknown but almost certainly perilously low number of adult tortoises in the wild. This study has produced the first reliable population estimate of the ploughshare tortoise and shows that the species has declined rapidly because of poaching for the international pet trade. There is an urgent need for increased action both in Madagascar and along international trade routes if the extinction of the ploughshare tortoise in the wild is to be prevented.
Moringa oleifera seeds are currently being used as a livestock feed across tropical regions of the world due to its availability and palatability. However, limited knowledge exists on the effects of the raw seeds on ruminant metabolism. As such, the rumen stimulation technique was used to evaluate the effects of substituting increasing concentrations of ground Moringa seeds (0, 100, 200 and 400 g/kg concentrate dry matter (DM)) in the diet on rumen fermentation and methane production. Two identical, Rusitec apparatuses, each with eight fermenters were used with the first 8 days used for adaptation and days 9 to 16 used for measurements. Fermenters were fed a total mixed ration with Urochloa brizantha as the forage. Disappearance of DM, CP, NDF and ADF linearly decreased (P<0.01) with increasing concentrations of Moringa seeds in the diet. Total volatile fatty acid production and the acetate to propionate ratio were also linearly decreased (P<0.01). However, only the 400 g/kg (concentrate DM basis) treatment differed (P<0.01) from the control. Methane production (%), total microbial incorporation of 15N and total production of microbial N linearly decreased (P<0.01) as the inclusion of Moringa seeds increased. Though the inclusion of Moringa seeds in the diet decreased CH4 production, this arose from an unfavourable decrease in diet digestibility and rumen fermentation parameters.
While our fascination with understanding the past is sufficient to warrant an increased focus on synthesis, solutions to important problems facing modern society require understandings based on data that only archaeology can provide. Yet, even as we use public monies to collect ever-greater amounts of data, modes of research that can stimulate emergent understandings of human behavior have lagged behind. Consequently, a substantial amount of archaeological inference remains at the level of the individual project. We can more effectively leverage these data and advance our understandings of the past in ways that contribute to solutions to contemporary problems if we adapt the model pioneered by the National Center for Ecological Analysis and Synthesis to foster synthetic collaborative research in archaeology. We propose the creation of the Coalition for Archaeological Synthesis coordinated through a U.S.-based National Center for Archaeological Synthesis. The coalition will be composed of established public and private organizations that provide essential scholarly, cultural heritage, computational, educational, and public engagement infrastructure. The center would seek and administer funding to support collaborative analysis and synthesis projects executed through coalition partners. This innovative structure will enable the discipline to address key challenges facing society through evidentially based, collaborative synthetic research.
In a longitudinal cohort study of young Australian adults, we reported that for women higher baseline levels of fish consumption were associated with reduced incidence of new depressive episodes during the 5-year follow-up. Fish are high in both n-3 fatty acids and tyrosine. In this study, we seek to determine whether n-3 fatty acids or tyrosine explain the observed association. During 2004–2006, a FFQ (nine fish items) was used to estimate weekly fish consumption among 546 women aged 26–36 years. A fasting blood sample was taken and high-throughput NMR spectroscopy was used to measure 233 metabolites, including serum n-3 fatty acids and tyrosine. During 2009–2011, new episodes of depression since baseline were identified using the lifetime version of the Composite International Diagnostic Interview. Relative risks were calculated using log-binomial regression and indirect effects estimated using the STATA binary_mediation command. Potential mediators were added to separate models, and mediation was quantified as the proportion of the total effect due to the mediator. The n-3 DHA mediated 25·3 % of the association between fish consumption and depression when fish consumption was analysed as a continuous variable and 16·6 % when dichotomised (reference group: <2 serves/week). Tyrosine did not mediate the association (<0·1 %). Components in fish other than n-3 fatty acids and tyrosine might be beneficial for women’s mental health.
Here we report on the material chemistry following crystallization in the presence of water vapor of chlorinated formamidinium lead-triiodide (NH2CH = NH2PbI3−xClx) perovskite films. We found in-situ exposure to water vapor reduces, or possibly eliminates, the retention of chlorine (Cl) inside NH2CH = NH2PbI3−xClx crystals. There is a strong tendency toward Cl volatility, which indicates the sensitivity of these materials for their integration into solar cells. The requisite for additional efforts focused on the mitigation of water vapor is reported. Based on the in situ results, hot casting (<100 °C) in dry conditions demonstrates improved film coverage and Cl retention with efficiencies reaching 12.07%.
We have observed the oxygen-rich SNR 1E 0102.2-7219 with the integral field spectrograph WiFeS at Siding Spring Observatory and discovered sulfur-rich ejecta for the first time. Follow-up deep DDT observations with MUSE on the VLT (8100 s on source) reaching down to a noise level of ~5 × 10−20ergs−1cm−2Å−1spaxel−1 have led to the additional discovery of fast-moving hydrogen as well as argon-rich and chlorine-rich material. The detection of fast-moving hydrogen knots challenges the interpretation that the progenitor of 1E 0102 was a compact core of a Wolf-Rayet star that had shed its entire envelope. In addition to the detection of hydrogen and the products of oxygen-burning, this unprecedented sharp (0.2″ spaxel size at ~0.7″ seeing) and deep MUSE view of an oxygen-rich SNR in the Magellanic Clouds reveals further exciting discoveries, including [Fe xiv]λ5303 and [Fe xi]λ7892 emission, which we associate with the forward shock. We present this exciting data set and discuss some of its implications for the explosion mechanism and nucleosynthesis of the associated supernova.
Epidemiological evidence regarding the association between carbohydrate intake, glycaemic load (GL) and glycaemic index (GI) and risk of ovarian cancer has been mixed. Little is known about their impact on ovarian cancer risk in African-American women. Associations between carbohydrate quantity and quality and ovarian cancer risk were investigated among 406 cases and 609 controls using data from the African American Cancer Epidemiology Study (AACES). AACES is an ongoing population-based case–control study of ovarian cancer in African-Americans in the USA. Cases were identified through rapid case ascertainment and age- and site-matched controls were identified by random-digit dialling. Dietary information over the year preceding diagnosis or the reference date was obtained using a FFQ. Multivariable logistic regression models were used to estimate odds ratios and 95 % CI adjusted for covariates. The OR comparing the highest quartile of total carbohydrate intake and total sugar intake v. the lowest quartile were 1·57 (95 % CI 1·08, 2·28; Ptrend=0·03) and 1·61 (95 % CI 1·12, 2·30; Ptrend<0·01), respectively. A suggestion of an inverse association was found for fibre intake. Higher GL was positively associated with the risk of ovarian cancer (OR 1·18 for each 10 units/4184 kJ (1000 kcal); 95 % CI 1·04, 1·33). No associations were observed for starch or GI. Our findings suggest that high intake of total sugars and GL are associated with greater risk of ovarian cancer in African-American women.
Background: One of the primary differences between Cognitive Behavioral Therapy (CBT) and Acceptance and Commitment Therapy (ACT) for anxiety is the approach to managing negative thoughts. CBT focuses on challenging the accuracy of dysfunctional thoughts through cognitive restructuring exercises, whereas ACT attempts to foster acceptance of such thoughts through cognitive defusion exercises. Previous research suggests that both techniques reduce the distress associated with negative thoughts, though questions remain regarding the benefit of these techniques above and beyond exposure to feared stimuli. Aims: In the present study, we conducted a brief experimental intervention to examine the utility of cognitive defusion + in-vivo exposure, cognitive restructuring + in-vivo exposure, and in-vivo exposure alone in reducing the impact of negative thoughts in patients with social anxiety disorder. Method: All participants completed a brief public speaking exposure and those in the cognitive conditions received training in the assigned cognitive technique. Participants returned a week later to complete a second exposure task and self-report measures. Results: All three conditions resulted in similar decreases in discomfort related to negative thoughts. ANOVA models failed to find an interaction between change in accuracy or importance and assignment to condition in predicting decreased distress of negative thoughts. Conclusions: These preliminary results suggest that changes in perceived importance and accuracy of negative thoughts may not be the mechanisms by which cognitive defusion and cognitive restructuring affect distress in the short-term.
Volunteer corn (VC) in hybrid corn has become more prevalent in recent years and can reduce grain yield. Nitrogen (N) management can influence VC interference in corn. Field experiments were established to determine the effects of N fertilizer management and VC interference on hybrid corn growth and grain yield. Treatments consisted of three VC densities (control, 0 plants m−2; low density, 1 plant m−2; high density, 4 plants m−2) and six N fertilizer treatments (0 kg N ha−1, 67 kg N ha−1 at planting, 67 kg N ha−1 at planting + 133 kg N ha−1 at V5 corn growth stage, 67 kg N ha−1 at planting + 133 kg N ha−1 at V10 corn growth stage, 200 kg N ha−1 at V5 corn growth stage, and 200 kg N ha−1 at V10 corn growth stage). The effect of VC on hybrid corn was dependent on N rate. When 200 kg N ha−1 was applied, regardless of application timing, hybrid corn dry weight, hybrid corn N content, and hybrid corn grain yield were reduced by the high VC density. However, when VC grain yield was added to hybrid corn grain yield, VC density did not affect total grain yield. When 0 and 67 kg N ha−1 were applied, neither hybrid corn dry weight nor hybrid corn N content was affected by either VC density, but the high VC density reduced hybrid corn grain yield for both N rates by 19% and total grain yield by 9 and 10%, respectively. Application timing of N fertilizer had no effect on hybrid corn dry weight, N content, or grain yield. However, late N fertilizer applications (200 kg N ha−1 at V10 and 67 kg N ha−1 at planting +133 kg N ha−1 at V10) resulted in greater VC N content, VC grain yield, and total yield. Assuming the harvestability of VC, the ability of a late N treatment (V10) to maximize total grain yield allows growers to use a late N application to reduce the competitive effects of VC in hybrid corn.
Rapid adoption of glyphosate-resistant (GR) corn hybrids has led to the
reemergence of volunteer corn as a problematic weed in soybean and has made
controlling the initial stand of corn in a replant situation more difficult.
If volunteer corn in soybean or the initial corn stand in a replant
situation is not controlled, yield loss can occur. Clethodim and glufosinate
are often used to control GR corn in corn replant situations and in soybean.
The objectives of this research were to evaluate the response of two hybrid
corn varieties and their F2 progeny to clethodim and glufosinate
and to evaluate the effect of plant nitrogen (N) concentration on clethodim
and glufosinate efficacy. First, a dose-response study was conducted with
clethodim and glufosinate on DeKalb 60-18 and 60-18F2, and DeKalb
63-42 and 63-42F2 to compare the response of the hybrids and
their F2 progeny to the herbicides. DeKalb 63-42 was more
tolerant to clethodim than 60-18 and 60-18F2. No differences were
found between the hybrids and their respective F2 progeny in the
response to clethodim or glufosinate. In a second dose-response study
assessing the effect of N conditions on herbicide efficacy, both clethodim
and glufosinate were less injurious to plants growing in low N than in high