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Estudios geofísicos, técnicas de sensores remotos y realización de mapas topográficos con GPS diferencial y vehículos aéreos no tripulados (VANT) han proporcionado una mejor comprensión de la organización espacial de los conjuntos departamentales y barrios en Teotihuacán. Nuestras investigaciones demuestran que en contraste con el mapa producido por el Teotihuacan Mapping Project (TMP) (Millon et al. 1973), el distrito de Tlanjinga es más rectangular y está más formalmente organizado, mientras que los conjuntos individuales tienen formas más irregulares, como lo había mostrado la excavación de Tlajinga 33 (Widmer y Storey 1993). Esto difiere de los nítidos cuadrados y rectángulos interpretados por las reconstrucciones arquitectónicas del TMP. El estudio de las imágenes satelitales mostró manchas blanquecinas en el terreno que parecen corresponder con áreas elevadas del mismo y con la desintegración de los aplanados de cal, destruidos por el tiempo y el trabajo agrícola. También verificamos la continuación del trazo de la Calzada de los Muertos que cruza este distrito mediante la modificación del relieve ocasionada por la excavación realizada en la toba volcánica subyacente (tepetate).
Teotihuacan's Tlajinga district is a cluster of neighborhoods on the southern periphery of the city best known for earlier investigations at Compound 33:S3W1. New research includes excavations at two other apartment compounds and along the southern extension of the Street of the Dead. Excavation contexts, major finds, chronology, and preliminary interpretations are the subject of this article. We highlight evidence attesting to a major obsidian-blade workshop at Compound 17:S3E1, offerings, and other features at that compound and Compound 18:S3E1, and the tempo and processes of urbanization viewed through well-recorded stratigraphic sequences of the compounds and the Street of the Dead. We conclude that significant occupation began in the Miccaotli phase, but it was not until some point in the Early Tlamimilolpa phase that the dominant housing type became apartment compounds; the continuation of the axis of Street of the Dead in the district was accomplished by excavating in the volcanic tuft substrate (tepetate) and could have been undertaken by the inhabitants of the district themselves; and the presence of items such as a sculpted stone face, marine shell, and polychrome pottery demonstrates that commoners at Teotihuacan enjoyed some access to finer items within the interregional economy.
The original research by the Teotihuacan Mapping Project (TMP) identified a large number of obsidian workshops within Teotihuacan based on surface concentrations of production debris. Clark (1986b) questioned the validity of these identifications and called for subsurface excavation to confirm the presence of in situ workshop locales. This article summarizes the results from the excavation of one of the obsidian workshops identified in the Tlajinga district of Teotihuacan at Compound 17:S3E1 (Compound 17). We describe the excavations, discuss the lithic technology, and examine the subsurface contexts in terms of what they tell us about in situ obsidian craft activity. Excavations confirm that Compound 17 was a locus of large-scale obsidian craft production during the Classic period. While only a single test case, these results suggest that surface remains at Teotihuacan can be a useful guide in identifying craft production areas when they are confirmed through subsurface testing.
To assess the safety of, and subsequent allergy documentation associated with, an antimicrobial stewardship intervention consisting of test-dose challenge procedures prompted by an electronic guideline for hospitalized patients with reported β-lactam allergies.
Retrospective cohort study.
Large healthcare system consisting of 2 academic and 3 community acute-care hospitals between April 2016 and December 2017.
We evaluated β-lactam antibiotic test-dose outcomes, including adverse drug reactions (ADRs), hypersensitivity reactions (HSRs), and electronic health record (EHR) allergy record updates. HSR predictors were examined using a multivariable logistic regression model. Modification of the EHR allergy record after test doses considered relevant allergy entries added, deleted, and/or specified.
We identified 1,046 test-doses: 809 (77%) to cephalosporins, 148 (14%) to penicillins, and 89 (9%) to carbapenems. Overall, 78 patients (7.5%; 95% confidence interval [CI], 5.9%–9.2%) had signs or symptoms of an ADR, and 40 (3.8%; 95% CI, 2.8%–5.2%) had confirmed HSRs. Most HSRs occurred at the second (ie, full-dose) step (68%) and required no treatment beyond drug discontinuation (58%); 3 HSR patients were treated with intramuscular epinephrine. Reported cephalosporin allergy history was associated with an increased odds of HSR (odds ratio [OR], 2.96; 95% CI, 1.34–6.58). Allergies were updated for 474 patients (45%), with records specified (82%), deleted (16%), and added (8%).
This antimicrobial stewardship intervention using β-lactam test-dose procedures was safe. Overall, 3.8% of patients with β-lactam allergy histories had an HSR; cephalosporin allergy histories conferred a 3-fold increased risk. Encouraging EHR documentation might improve this safe, effective, and practical acute-care antibiotic stewardship tool.
The aim of the study was to determine whether routine probiotic supplementation (RPS) with Lactobacillus rhamnosus GG (LGG) or Lactobacillus acidophilus +Lactobacillus bifidum is associated with reduced risk of necrotising enterocolitis (NEC)≥Stage II in preterm neonates born at ≤32 weeks’ gestation. We conducted a retrospective cohort study on the effect of probiotic supplementation in very low birth weight infants in our neonatal unit by comparing two periods: before and after supplementation. The incidence of NEC≥Stage II, late-onset sepsis and all-cause mortality was compared for an equal period ‘before’ (Period I) and ‘after’ (Period II) RPS with LGG or L. acidophillus+L. bifidum. Multivariate logistic regression analysis was conducted to adjust for relevant confounders. The study population was composed of 261 neonates (Period I v. II: 134 v. 127) with comparable gestation duration and birth weights. In <32 weeks, we observed a significant reduction in NEC≥Stage II (11·3 v. 4·8 %), late-onset sepsis (16 v. 10·5 %) and mortality (19·4 v. 2·3 %). The benefits in neonates aged ≤27 weeks did not reach statistical significance. RPS with LGG or L. acidophillus+L. bifidum is associated with a reduced risk of NEC≥Stage II, late-onset sepsis and mortality in preterm neonates born at ≤32 weeks’ gestation.
Site-wide, assemblage-based lithic analyses help to elucidate community dynamics including variability in domestic economies, technological skill and decision making, exchange networks, and ritual practices. In this study we present the results of an analysis of over 36,000 lithic artifacts from the site of La Laguna, Tlaxcala. We compare Middle to Late Formative period (ca. 600–400 b.c.) and Terminal Formative period (ca. 100 b.c.–a.d. 150) deposits to examine transformations associated with urbanization and state formation during this interval. The residents of La Laguna had relatively equal and ample access to obsidian, and most production was organized independently by households. We identify blade production zones and variability in consumption patterns suggestive of different domestic, communal, and ceremonial activities. The introduction of bloodletters, elaborate large bifacial knives, and zoomorphic eccentrics to the Terminal Formative assemblage may indicate the emergence of higher statuses, new social roles, and militaristic symbolism during this period.
The households of Formative period central Mexico represent critical loci for understanding major social transformations during a millennium (900 b.c.– a.d. 100) that witnessed the expansion and contraction of several macro-regional stylistic and economic networks, formalization of enduring political and religious institutions, and initial urbanization and state formation. Households and their constituent members used style to articulate important elements of their identity through practices of group consumption and personal adornment. In this study we consider style within the context of ceramic serving vessels and portable adornments primarily from sites in the state of Tlaxcala. We evaluate the manner in which dimensions of stylistic expression in these material goods contributed to shifting conceptualizations of household and individual identity and their articulation with community and supra-community social networks, noting the generally collective or affinitive manipulation of styles with means of socially differentiating age, status, and other dimensions of identity.
The Grammatical Structures Comprehension Test (CEG) was used to analyze grammatical comprehension problems in native Spanish-speaking children with Specific Language Impairment (SLI). The test is divided into 20 blocks containing the most common grammatical structures in Spanish. Our objective was to establish whether the CEG was sensitive in detecting these problems and whether there were differential patterns in grammatical comprehension between children with SLI (14 participants) and two control groups: a chronological control group (CC) with 14 participants and a linguistic control group (LC) also with 14 participants. We found significant differences between the SLI group and the chronological control participants (Box’s M = 63.080, F = 1, 159, p = .238), with a correct classification rate of 85.7 % in the discriminant function analysis. These differences did not occur in all the blocks, in which we identified a range of different performance patterns that varied according to the structures being analyzed. This work helps to clarify certain questions about grammatical comprehension in children with SLI and contributes to the debate on delay vs. “delay within the delay”.
Recent work at La Laguna in Central Mexico provides an excellent illustration of the way in which information from architecture, food remains, ceramic vessels and chemical signatures can be brought together to demonstrate communal feasting associated with specific structures and public spaces. Structure 12M-3 contained a range of evidence indicative of food preparation and consumption. Ritual effigy vessels depicted deities connected with food and fertility, and fire and the hearth. Taken together, the several lines of evidence indicate that Structure 12M-3 was a special building, located directly behind the main temple and devoted to the preparation and production of communal feasts that were held in the adjacent plaza. This provides new insights into community life in the urban centres of early Mesoamerica.
In most developed countries, motor vehicle accidents are a leading cause of death among young people, and a large proportion of motor vehicle accidents are alcohol-related. In Spain there are no currently available instruments for assessing positive expectancies related to drinking and driving behavior. Attempting to modify these expectancies may be an effective prevention approach, so there is a need for a valid and reliable scale to measure the construct. The aims of the present study were to translate, culturally adapt, and examine the psychometric properties of a Spanish-language version of the Positive Expectancies for Drinking and Driving for Youth (PEDD-Y) in a sample of Spanish young adults. A total of 352 college students with drivers licenses were recruited at a university in southeast Spain. We examined the factor structure, psychometric properties (reliability and validity) and temporal stability of the Spanish version of the PEDD-Y among Spanish young adult drivers. Findings indicated that the Spanish version of the PEDD-Y demonstrated satisfactory psychometric properties and was shown to significantly predict lifetime prevalence and future intentions to drink and drive as well as riding with a drunk driver. The Convenience factor performed with the most consistent reliability and predictive validity. Limitations and future research questions are discussed.
Urbanization of the world's first cities involved the social integration of greater scales of community membership as well as the social differentiation of individuals along the continua of wealth, power, and occupational specialization that define urban landscapes. This article considers the causal role of public ritual in these processes during the period of incipient urbanism in central Mexico (c. 600 BC–AD 100) by examining temple and plaza offerings at La Laguna, a town within an urbanizing cultural landscape whose inhabitants participated in the transformative exchanges that resulted in urban state capitals such as Teotihuacan.
It is generally acknowledged that the popularity of breast-feeding, expressed in terms of the frequency with which it is taken up, and the length of time it is continued, is declining, and that, especially among populations of the Third World, the implications of this decline for infant health are likely to be serious and far reaching.
Breast-feeding in the human and higher primates unlike the case of most other mammals, is learned rather than instinctive; over a long time it has been shown to be highly labile. Its success appears to depend not only upon the capacity of the mother to lactate, i.e. to produce milk, or on the child's ability to suckle, but perhaps more significantly, on the mother's desire to breast-feed, on the availability of sufficient reference models upon which she can base her own performance and draw upon for psycho-social support during lactation. In modern settings breast-feeding is likely to involve the mother in complex and new role situations, and to become increasingly vulnerable to the social characteristics of the environment in which she operates.
It has been suggested that the outer young Galactic halo globular cluster population might be associated (or even the nuclei) to tidal disrupted dwarf spheroidals, now extinct galaxies. If this hypothesis is true, these systems might be still surrounded by a distinct and detectable stellar population similar to that of their progenitor galaxies. We have designed a systematic photometric survey of Galactic globular clusters to unveil the possible remnants of the systems where they were formed and estimate their contribution to the Galatic halo.
Two Terminal Formative (ca. 100 B. C.–A.D. 100) domestic areas of La Laguna, Tlaxcala, are compared to examine variability in residential structures, assemblages, and practices, and their correlation to status differences at this midsize regional center during the period of initial central Mexican urbanization and state formation. Combining multiple lines of evidence, the study assesses the applicability of previous frameworks for investigating household status to this particular community. It demonstrates significant differences between elite and commoner residences in architectural elaboration, labor mobilization, access to certain foreign goods, and particular ritual practices, but general similarities in domestic economies and more restrained differentiation informs of personal adornment and domestic ritual. These conclusions are consistent with demarcated lineage ranking but relatively minor wealth accumulation by a more rural elite located peripherally to larger cities and polities.
Obsidian prismatic blades were widely traded across Mesoamerica during the Early and Middle Formative periods. However, it was not until the Late Formative period (400 b.c.—a.d. 100) that prismatic blade cores began to be exchanged extensively. Although it is generally accepted that the trading of blades preceded the trading of cores by almost 1,000 years, little is know about the structure of blade trading during the Early and Middle Formative periods. We describe three distributional models for the trade of obsidian prismatic blades: whole-blade trade, processed-blade trade, and local-blade production. These models were evaluated using obsidian consumption data from Oaxaca, the Basin of Mexico, and Tlaxcala. The results indicate that Formative period blade trade involved different forms over time and space.