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This article presents a compositional analysis of metal artifacts from the Postclassic period (a.d. 1100–1450) city of Mayapan, Yucatan, Mexico. We document metallurgical production at R-183, an elite residential group and one of the most significant archaeological contexts associated with metalworking at Mayapan. Salvage excavations in 1998 recovered a small cache containing 282 copper bells, two miniature ceramic vessels filled with metal, and production debris including loose casting sprues and miscast bells. Metallographic analysis of a small copper bell and wire fragments from the cache reveals lost-wax casting production techniques. X-ray fluorescence spectrometry (XRF) of metal artifacts provides insight into the range of metals used by the R-183 metalworkers, which included copper-lead, copper-tin, and copper-arsenic alloys, and how these alloys compare to assemblages recovered from other contexts at the city. Our findings strongly suggest the use of remelting and casting techniques, likely utilizing remelted metals of both West and central Mexican origin, together with the use of imported goods made from a range of copper alloys.
The spatial contexts of effigy censer and figurine molds at Mayapan, Yucatan, Mexico suggest a tightly controlled industry in which elite representatives of state government and religious orders exerted oversight over production and distribution. Attached artisans at Mayapan made these and other restricted goods for residents of palaces and patrons of the city's public buildings. The study of effigy ceramic production reveals that, like earlier, Classic period Maya kingdoms, Postclassic elites also sponsored the crafting of symbolically charged goods. This finding expands understanding of Postclassic period economic organization, which is best-known for its expansive regional market exchange. The limited distribution of effigy censers and figurines further attests their primary use in the context of state-sponsored ceremonies and, to a lesser extent, high-status mortuary settings. Unlike other places and times in Mesoamerica, neither figurines nor effigy censers are representative of household-scale religious practice for the majority of urban residents at Mayapan.
This study focuses on the role of the population structure of Leishmania spp. on the adaptive capacity of the parasite. Herein, we investigate the contribution of subpopulations of the L. (V.) braziliensis Thor strain (Thor03, Thor10 and Thor22) in the profile of murine macrophages infection. Infection assays were performed with binary combinations of these subpopulations at stationary phases. The initial interaction time showed major effects on the combination assays, as demonstrated by the significant increase in the infection rate at 5 h. Based on the endocytic index (EI), Thor10 (EI = 563.6) and Thor03 (EI = 497) showed a higher infection load compared to Thor22 (EI = 227.3). However, the EI decreased in Thor03 after 48 h (EI = 447) and 72 h (EI = 388.3) of infection, and showed changes in the infection level in all Thor10/Thor22 combinations. Assays with CellTrace CFSE-labelled Thor22 promastigotes indicated an increase (~1.5 fold) in infection by this subpopulation in the presence of Thor10 when compared to the infection profile of Thor03/Thor22 combinations in the same proportions. In addition, the potential of these subpopulations, alone or in binary combinations, to modulate the expression of cytokines and nitric oxide (NO) in vitro was investigated. Lower NO and tumour necrosis factor-α production levels were observed for all Thor10/Thor22 combinations at 24 h compared to these subpopulations alone. In contrast, Thor03/Thor22 combination assays increased IL-10 production at this time. Collectively, these results provide in vitro evidence on the potential of L. (V.) braziliensis population structure to play a relevant role in a host infection by this parasite.
Cruzia tentaculata is a helminth parasite of marsupials and has a wide geographic distribution from Mexico to Argentina. The aim of this study was to analyse the genetic population structure of this nematode along the Atlantic Forest biome. Cruzia tentaculata specimens were recovered from Didelphis aurita, Didelphis albiventris and Philander quica in 9 localities. Morphological and morphometric data were investigated for phenotypic diversity among localities and hosts using multivariate discriminant analysis of principal components. Phylogenetic relationships of C. tentaculata were determined using maximum likelihood and Bayesian inference. The population structure was analysed by fixation indices, molecular variance analysis, Tajima's D and Fu's Fs neutrality tests, Mantel tests and Bayesian clustering analysis. A higher significant morphometric difference for males was observed between localities. In the haplogroup networks, 2 groups were recovered, separating locations from the north and from the south/southeast. The morphometric variation in C. tentaculata between different localities was compatible with this north and southeast/south pattern, suggesting adaptation to different ecological conditions. Population genetic analyses suggested a pattern of evolutionary processes driven by Pleistocene glacial refugia in the northeast and southeast of the Atlantic Forest based on the distribution of genetic diversity.
The ‘Critically Endangered’ Black-winged Trumpeter Psophia obscura is endemic to the Belém Centre of Endemism in extreme eastern Amazonia and has a declining population and range. Here we report on a five-year (2016–2020) systematic camera-trap (n = 61) study of the species in Gurupi Biological Reserve, one of its most important conservation areas. We used a multi-season occupancy model to identify factors affecting occupancy rates and to assess occupancy trends in the reserve. Occupancy was negatively related to elevation and site-level tree density, and was positively related to post-logging recovery times. Average annual occupancy rates remained stable throughout the study period (ranging between 0.57 and 0.67) and this stability was largely driven by high between-year survival rates. Results confirm that the Black-winged Trumpeter is an interior-forest specialist that is highly sensitive to forest disturbance, which underlines the importance of the Gurupi Biological Reserve as a core site for the conservation of the species. However, the species is long-lived, so continuous monitoring is needed to further clarify population trends. We also recommended that the status of the species in other forest remnants, most of which remain unprotected, is assessed.
In Germany, learning through research has experienced a great upswing in the last decade, especially through project funding and research within the framework of the national “Quality Pact for Teaching” (QPL, Qualitätspakt Lehre). Forschendes Lernen – as the concept is called in German – was developed in Germany about fifty years ago. In the last twenty years, this teaching and learning concept has been adapted to current conditions and challenges through the commitment and creative ideas of various university players. Forschendes Lernen became the foundation for undergraduate research in Germany.
In this paper, we give the generic classification of the singularities of 3-parameter line congruences in $\mathbb {R}^{4}$. We also classify the generic singularities of normal and Blaschke (affine) normal congruences.
This article analyzes the US sociologist Donald Pierson’s views on the process of modernization as expressed in research he conducted while residing in Brazil from the 1930s to the 1950s. Looking first at his study on race relations in Bahia and then at his investigations of rural communities in the São Francisco Valley, it shows that Pierson’s exchange with local intellectuals was decisive to his readings of Brazil’s rural, patriarchal past and his understanding of the potential for building a modern social order out of these traditions. His perspective was also evident during the debate on the relation between racism and modernity in the context of the UNESCO Race Relations Project. This examination of Pierson’s work likewise signals how transnational dialogue between the Global North and South contributed to the sociological debate on modernization, and how US scholars ascribed more than one meaning to the modernizing changes underway in peripheral countries around the world.
This article investigates the complex entanglement of neutrality and displacement in Hong Kong and Macau with a focus on the impact of and responses to an unprecedented influx of refugees during the Second World War. Displaced persons were of central importance in shaping the ambiguous experience of neutrality before Hong Kong's occupation by Japan in late 1941 and until the end of the war in Macau. Building on Elizabeth Sinn's conceptualization of Hong Kong as an ‘in-between place’, this article considers these two foreign-ruled territories as ‘in-between places’ where multi-layered transborder flows developed in an ‘in-between time’ of neutrality. Highlighting similarities and connections between Hong Kong and Macau, it argues that neutrality was shaped by the movement of refugees and that refugees often experienced neutrality differently depending on perceptions of race, class, and nationality. The presence of diverse communities of refugees shaped multiple dimensions of urban life, with colonial concerns for spatial order and social control co-existing with humanitarian co-operation. The discourses and practices around refugees are an important precedent to understanding post-war refugeedom in these territories.
Changes in the item order of the US Household Food Security Survey Module (USHFSSM) were performed throughout time. This study aimed to compare the psychometric properties of the general and specific factors of the 2000 and 2012 versions of the USHFSSM to measure the construct of food insecurity in two Portuguese samples of households with children.
Design:
Cross-sectional.
Setting:
Portugal.
Participants:
An adaptation of the 2000 version was applied to 839 adults (from households with children aged 7–17 years) from the National Food, Nutrition and Physical Activity Survey 2015–2016, while the 2012 version was used among 2855 families from the Generation XXI birth cohort.
Results:
The 2000 version showed to have a stronger ωh than the 2012 version (0·89 v. 0·78 for the general factor), as well as eigenvalues higher than 1 for the general factor (eigenvalues equal to 9·54, 0·97 and 0·80, for the general factor, specific factor 1 and specific factor 2, respectively), while the 2012 version had also the contribution of specific factors to explain food insecurity (eigenvalues equal to 9·40, 2·40 and 1·20, for general factor and specific factors 1 and 2, respectively). Good internal consistency (ωt = 0·99, for both versions) was obtained.
Conclusions:
In conclusion, the 2000 and 2012 versions of the USHFSSM showed good psychometric properties; however, the 2000 version has stronger general factor, while the 2012 version also has the contribution of specific factors.
Prenatal exposure to dichlorodiphenyldichloroethylene (p,p´-DDE) may interfere with fetal development; however, studies evaluating anthropometry and gestational age at birth show inconsistent results. Typically, p,p´-DDE exposure has been measured during the third trimester and missed the key early pregnancy period. We evaluated the association between p,p´-DDE exposure before week 18 of pregnancy and anthropometry at birth, as well as gestational length, in 170 mother–child pairs from a cohort study in a flower-growing mexican region. Maternal serum p,p´-DDE concentrations were determined by gas chromatography. The associations between p,p´-DDE and z-scores of birth weight, birth length, and gestational age were evaluated by linear multiple regression models. Logistic regression models were used for low birth weight and small size for gestational age. Effect modification by child’s sex was explored. The average gestational age at the blood sample extraction was 10.6 weeks. p,p'-DDE was detected in 64.7% of mothers, at a geometric mean of 0.24 ng/mL. Prenatal p,p´-DDE exposure was not associated with the birth outcomes in the whole sample. However, a high p,p´-DDE exposure was marginally associated with greater small for gestational age risk in male newborns (OR≥0.076ng/mL vs <0.076 ng/mL = 3.09, 95% CI: 0.61; 15.58), but not in female (p for interaction = 0.08).
Even though, we found no reductions in anthropometric measurements or gestational length associated with early prenatal p,p´-DDE exposure, the potential effect modification by infant’s sex in terms of small for the gestational age risk deserves future studies.
Subsistence hunting provides an important food source for rural populations in tropical forests but can lead to wildlife depletion. Management of wildlife resources depends on assessments of hunting sustainability. We assessed the sustainability of subsistence hunting in two Amazonian Extractive Reserves. We examined hunting data from a community-based monitoring programme conducted in 30 communities during 63 consecutive months to address temporal trends in hunting yields in terms of catch per unit of effort of all game species and the six most hunted species. We also assessed the prey profiles across different communities. Game species composition did not differ between monitored communities, and the most hunted species were Tayassu pecari, large cracids, Cuniculus paca, Mazama spp., Tapirus terrestris and Pecari tajacu. Catch per unit of effort was stable for all game species and each of the most hunted species, indicating that hunting was generally sustainable. These findings reflect the exceptionally low human population density and continuous forest cover of the study landscape, and long-term hunting sustainability and local protein acquisition will depend on maintaining these social and environmental settings. The results also show that large Sustainable Use Protected Areas can help foster sustainable game management and should thus be included in public policies.
Depression in older adults with multiple medical comorbidities can contribute to clinical deterioration, and increased mortality. Electroconvulsive therapy (ECT) is the first-line treatment for these patients. This study aimed to evaluate the effectiveness and safety of subcutaneous (SC) ketamine as an alternative to ECT. We reviewed the medical records of all consecutive older inpatients with severe depression and multiple medical comorbidities who were referred for ECT but treated with SC ketamine over 1 year in our institution. Demographic data, DSM-5 diagnosis, MÅDRS score, and CGI score were analyzed. Twelve patients aged 67–94 years were included. All patients were rated as severely ill, 83% were women, with a mean of 12.6 (SD, 1.4) medical comorbidities. Remission was achieved in 75% of the intention-to-treat population and 100% of treatment completers. The number of sessions ranged from 1 to 6, and days until remission from 1 to 16. Patients remained without relapse for 8–28 months. SC ketamine was safe and well tolerated, and most adverse events were mild and transient. Although limited by the retrospective open-label design of the study and small sample size, our findings provide a potential new indication for ketamine: treatment of severe depression, not necessarily resistant to antidepressants, in older patients with multiple medical comorbidities, at risk of clinical deterioration, and referral for ECT. SC ketamine was highly effective in this population, with no relapse and good tolerance. Randomized controlled trials are needed to adequately test the use of ketamine in this specific group.
This article focuses on designing and evaluating conversation practice in a second language (L2) with a robot that employs human spoken and non-verbal interaction strategies. Based on an analysis of previous work and semi-structured interviews with L2 learners and teachers, recommendations for robot-led conversation practice for adult learners at intermediate level are first defined, focused on language learning, on the social context, on the conversational structure and on verbal and visual aspects of the robot moderation. Guided by these recommendations, an experiment is set up, in which 12 pairs of L2 learners of Swedish interact with a robot in short social conversations. These robot–learner interactions are evaluated through post-session interviews with the learners, teachers’ ratings of the robot’s behaviour and analyses of the video-recorded conversations, resulting in a set of guidelines for robot-led conversation practice: (1) societal and personal topics increase the practice’s meaningfulness for learners; (2) strategies and methods for providing corrective feedback during conversation practice need to be explored further; (3) learners should be encouraged to support each other if the robot has difficulties adapting to their linguistic level; (4) the robot should establish a social relationship by contributing with its own story, remembering the participants’ input, and making use of non-verbal communication signals; and (5) improvements are required regarding naturalness and intelligibility of text-to-speech synthesis, in particular its speed, if it is to be used for conversations with L2 learners.
The chapter describes the Brazilian mining sector, focusing on its competitive dynamics, strategic challenges and technological needs, as well as institutional arrangements to promote innovation. It aims at identifying how mining firms and mining, equipment, technology and services (METS) firms deal with innovation protection and technology transfer in Brazil. The primary sample includes resident and non-resident companies. The chapter covers the key technological areas of mining patenting in Brazil, as well as the main stakeholders of those patents. Through import contracts, technology transfer among firms and with other stakeholders of the mining industry, mainly universities, is reviewed, and the role of foreign METS is highlighted in this process. The chapter also presents as a case study the bigger Brazilian mining enterprise: Vale S.A. The focus is on Vale’s strategies to mitigate external challenges and to face technological needs through innovation.
The development of colorectal cancer involves some morphological changes, and in the initial stage, pre-neoplastic lesions called aberrant crypt foci (ACF) appear. Thus, an intervention with sources of bioactive compounds such as Hibiscus sabdariffa L., rich in phenolic compounds and anthocyanins, could attenuate the risk of developing these lesions due to its antioxidant, anti-inflammatory and anti-proliferative properties. Therefore, the aim of this study was to evaluate the effects of 5 % and 10 % supplementation of dehydrated H. sabdariffa calyces (DHSC) during the development of 1,2-dimethylhydrazine-induced pre-neoplastic lesions in male BALB/c mice. The characterisation of DHSC was carried out. The in vivo experiment lasted 12 weeks, and the animals were randomly divided into three experimental groups: the control group (CON) and the supplemented groups with 5 % DHSC and 10 % DHSC. The activities of liver enzymes catalase (CAT) and superoxide dismutase were determined. In addition, ACF, SCFA, presence of inflammatory infiltrates, goblet cells and leucocytes in the colonic mucosa were quantified. There was a significant reduction in ACF and the presence of inflammatory infiltrates in the colon of animals in groups 5DHSC and 10DHSC. In addition, the 10DHSC group showed an increase in the activity of the CAT enzyme, in the production of butyrate and in the presence of natural killer cells in the colon, in addition to more hypertrophied goblet cells. Based on these findings, it is suggested that DHSC supplementation may be recommended to attenuate cellular responses in the early stage of pre-neoplastic lesions.
Worldwide, conservation initiatives have attempted to curb illegal harvest, use and trade of marine turtles at least since the 1950s. Despite some declines in local trade and consumption, these illegal activities are still often reported as a key threat to marine turtle populations. Reassessing and refining global conservation priorities for marine turtles allows us to formulate evidence-based strategies and effective interventions to address this threat. We surveyed a total of 103 marine turtle conservation researchers and practitioners globally to understand how conservation efforts can be better allocated to curb illegal harvest, use and trade. We explored the characteristics of these illegal activities, conservation priorities, challenges and lessons learnt. According to participants’ perceptions, progress has been achieved, but illegal harvest, use and trade remain pressing threats globally. Current challenges to addressing illegal activities relate to fisheries management, enforcement and legislation. Recommended priority actions include law and penalty enforcement, enhancing environmental literacy, awareness and stakeholder participation, and improving local conservation leadership and onshore/maritime management based on research. Based on participants' perceptions, we identify priorities for marine turtle conservation interventions that aim to curb illegal harvest, use and trade. Given the challenges of obtaining reliable information on sensitive topics such as illegal harvest, use and trade, further work should seek to validate our findings through empirical research. Further work could also seek to comprehend better how expert elicitation in conservation is influenced by individual experience, perspectives and goals.
A recent review paper on nepheline solid solutions dealt mainly with sodic varieties from nepheline syenites and differentiated alkali basaltic sills. Excel spreadsheets were provided for recalculating cell formulae in terms of the stoichiometric parameters ΔAlcavity cation charge and ΔTframework charge and molecular percentages of the end-members Ne, Ks, Ca-nepheline and excess Si (Qxs). Small amounts of tetrahedral divalent species (usually <0.10 wt.% though with up to 0.33 wt.% MgO) were related to a stuffed-tridymite end-member of ideal formula K8Mg4Si12O32 (denoted KsT2+-nepheline), although the equations used to calculate these end-members only considered Si, Al and Fe3+ as tetrahedral framework species. Recently, K-rich nepheline and kalsilite which contain up 0.54 wt.% MgO have been found in some feldspar-free mafic potassic volcanic rocks from central Brazil. Equations have been developed to deal rigorously with the presence of significant amounts of Mg (and Mn) in recalculating nepheline solid-solution parameters. In two related communications reworked spreadsheets are provided with examples of their use. High quality microprobe analyses of nepheline and kalsilite from magmatic rocks must include analyses for Mg and Mn and, if possible, estimates of Fe2+ contents.
Natural nepheline usually contains very small amounts of MgO (<0.1 wt.%), although these examples are mainly from Mg-poor alkaline igneous rocks such as nepheline syenites. However, this work shows that nepheline and kalsilite with much higher MgO concentrations can occur in the groundmass of strongly SiO2-undersaturated, feldspar-free, mafic volcanic rocks (i.e. olivine-rich foidites). Furthermore, a strong positive correlation is evident between their Mg and Fe contents. The occurrence of Mg-rich nepheline and kalsilite seems to be related to their derivation from Mg-rich magmas when compared to most of the host rocks investigated to date. Additionally, the physicochemical conditions of crystallisation seem to have an important role in the incorporation of ‘small’ divalent cations by these minerals. The prevalence of Mg-rich nepheline and kalsilite as late magmatic phases and the divergent Mg and Fe relationships for phenocrysts and ‘quenched’ groundmass crystals support this hypothesis. The positive correlation between Mg and Fe contents reflects their strong geochemical affinity and the entrance of Fe3+, Fe2+ and Mg2+ cations into the same crystallographic site of nepheline and kalsilite structures. The calculation of atomic formulae and stoichiometry parameters for nepheline-group minerals where data for the T2+ cations (e.g. Mg2+) are incorporated gives more reliable compositional parameters (see Paper 1). Calculated excess silica values (Si′) are affected significantly when the coupled substitution 2Al3+ = Mg2+ + Si4+ is considered. Thus, specific analyses of ‘small’ divalent cations are essential to obtain more realistic values of excess Si′, in particular, for nepheline and kalsilite that crystallised from Mg-rich, Si-poor, mafic–ultramafic alkaline lavas.