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1.
PLoS One ; 17(11): e0275916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36322539

RESUMO

Many humans live in large, complex political centers, composed of multi-scalar communities including neighborhoods and districts. Both today and in the past, neighborhoods form a fundamental part of cities and are defined by their spatial, architectural, and material elements. Neighborhoods existed in ancient centers of various scales, and multiple methods have been employed to identify ancient neighborhoods in archaeological contexts. However, the use of different methods for neighborhood identification within the same spatiotemporal setting results in challenges for comparisons within and between ancient societies. Here, we focus on using a single method-combining Average Nearest Neighbor (ANN) and Kernel Density (KD) analyses of household groups-to identify potential neighborhoods based on clusters of households at 23 ancient centers across the Maya Lowlands. While a one-size-fits all model does not work for neighborhood identification everywhere, the ANN/KD method provides quantifiable data on the clustering of ancient households, which can be linked to environmental zones and urban scale. We found that centers in river valleys exhibited greater household clustering compared to centers in upland and escarpment environments. Settlement patterns on flat plains were more dispersed, with little discrete spatial clustering of households. Furthermore, we categorized the ancient Maya centers into discrete urban scales, finding that larger centers had greater variation in household spacing compared to medium-sized and smaller centers. Many larger political centers possess heterogeneity in household clustering between their civic-ceremonial cores, immediate hinterlands, and far peripheries. Smaller centers exhibit greater household clustering compared to larger ones. This paper quantitatively assesses household clustering among nearly two dozen centers across the Maya Lowlands, linking environment and urban scale to settlement patterns. The findings are applicable to ancient societies and modern cities alike; understanding how humans form multi-scalar social groupings, such as neighborhoods, is fundamental to human experience and social organization.


Assuntos
Características da Família , Características de Residência , Humanos , Cidades , Meio Ambiente , Análise por Conglomerados
2.
PLoS One ; 15(4): e0230892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32255773

RESUMO

It is well known that the development of the ancient Maya civilization had significant and long-lasting impacts on the environment. This study assesses a large collection of faunal remains (>35,000 specimens) recovered over a span of several kilometers in and around the archaeological site of Ceibal, Guatemala, in order to determine whether the composition of animal resources was continuous throughout the site's history between 1000 BC and AD 1200, or whether there were any changes that could be attributed to sociopolitical or environmental causes. Results show a steep uniform decline in the number of freshwater mollusks across the site that occurred during the Preclassic to Classic transition, when large region-wide political changes, including the development of more complex and centralized political organization, took place throughout the Maya region. Evidence of species introductions (e.g., turkeys from central Mexico and possibly the Dermatemys river turtle from the Isthmus of Tehuantepec) and variations in resource exchange (e.g. marine shells) over time indicate that Ceibal was one of likely many communities involved in long-distance animal exchange networks. The results of the faunal analysis at Ceibal show how the ancient Maya had a complex and ever-changing relationship with the local wildlife, with outcomes that can still be observed in the environment today.


Assuntos
Arqueologia , Civilização , Animais , Guatemala
3.
ERJ Open Res ; 4(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29479538

RESUMO

A successful initiative to improve best care practice in IPF supported by electronic medical record changes http://ow.ly/ORxi30hBEmy.

4.
Int J Pharm Compd ; 21(5): 426-429, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216619

RESUMO

The stability of dalteparin 1,000 units/mL in 0.9% sodium chloride for injection stored in polypropylene syringes under refrigeration was examined. Dalteparin 1,000-units/mL syringes were prepared by adding 9 mL of 0.9% sodium chloride for injection to 1 mL of dalteparin sodium 10,000 unit/mL from commercial single-use syringes. Compounded solutions in 0.5-mL aliquots were transferred to 1-mL polypropylene syringes and sealed with a Luer lock tip cap and stored at refrigerated temperatures (2°C to 8°C) with ambient fluorescent light exposure. Syringes from three batches of dalteparin 1,000 units/mL were potency tested in duplicate by a stability-indicating high-performance liquid chromatography assay using a 0.5-mL sample at specified intervals. Visual and pH testing were performed on each batch. Samples were visually inspected for container integrity, color, and clarity. Samples for pH testing were prepared using a 1:1 dilution of dalteparin 1,000 units/mL in sterile water for injection and underwent duplicate analysis at each time point. High-performance liquid chromatography analyses showed a remaining percent of the initial dalteparin content at day 30 of 94.88% ± 2.11%. Samples remained colorless and clear with no signs of container compromise and no visual particulate matter at each time point. Throughout the 30-day study period, pH values remained within 0.3-pH units from the initial value of 5.84. Dalteparin 1,000 unit/mL in 0.9% sodium chloride for injection, packaged in 1-mL polypropylene syringes was stable for at least 30 days while stored at refrigerated conditions with ambient fluorescent light exposure.


Assuntos
Dalteparina/química , Cromatografia Líquida de Alta Pressão , Dalteparina/análise , Dalteparina/farmacologia , Estabilidade de Medicamentos , Inibidores do Fator Xa/farmacologia , Concentração de Íons de Hidrogênio , Injeções , Polipropilenos , Cloreto de Sódio , Seringas
5.
Int J Pharm Compd ; 21(2): 150-153, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28346210

RESUMO

The stability of alprostadil diluted in 0.9% sodium chloride stored in polyvinyl chloride (VIAFLEX) containers at refrigerated temperature, protected from light, is reported. Five solutions of alprostadil 11 mcg/mL were prepared in 250 mL 0.9% sodium chloride polyvinyl chloride (PL146) containers. The final concentration of alcohol was 2%. Samples were stored under refrigeration (2°C to 8°C) with protection from light. Two containers were submitted for potency testing and analyzed in duplicate with the stability-indicating high-performance liquid chromatography assay at specific time points over 14 days. Three containers were submitted for pH and visual testing at specific time points over 14 days. Stability was defined as retention of 90% to 110% of initial alprostadil concentration, with maintenance of the original clear, colorless, and visually particulate-free solution. Study results reported retention of 90% to 110% initial alprostadil concentration at all time points through day 10. One sample exceeded 110% potency at day 14. pH values did not change appreciably over the 14 days. There were no color changes or particle formation detected in the solutions over the study period. This study concluded that during refrigerated, light-protected storage in polyvinyl chloride (VIAFLEX) containers, a commercial alcohol-containing alprostadil formulation diluted to 11 mcg/mL with 0.9% sodium chloride 250 mL was stable for 10 days.


Assuntos
Alprostadil/química , Embalagem de Medicamentos , Excipientes/química , Inibidores da Agregação Plaquetária/química , Cloreto de Polivinila/química , Cloreto de Sódio/química , Vasodilatadores/química , Alprostadil/farmacologia , Alprostadil/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Concentração de Íons de Hidrogênio , Soluções Isotônicas , Luz , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/efeitos da radiação , Cloreto de Sódio/efeitos da radiação , Fatores de Tempo , Vasodilatadores/farmacologia , Vasodilatadores/efeitos da radiação
6.
Proc Natl Acad Sci U S A ; 112(14): 4268-73, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25831523

RESUMO

Our archaeological investigations at Ceibal, a lowland Maya site located in the Pasión region, documented that a formal ceremonial complex was built around 950 B.C. at the onset of the Middle Preclassic period, when ceramics began to be used in the Maya lowlands. Our refined chronology allowed us to trace the subsequent social changes in a resolution that had not been possible before. Many residents of Ceibal appear to have remained relatively mobile during the following centuries, living in ephemeral post-in-ground structures and frequently changing their residential localities. In other parts of the Pasión region, there may have existed more mobile populations who maintained the traditional lifestyle of the preceramic period. Although the emerging elite of Ceibal began to live in a substantial residential complex by 700 B.C., advanced sedentism with durable residences rebuilt in the same locations and burials placed under house floors was not adopted in most residential areas until 500 B.C., and did not become common until 300 B.C. or the Late Preclassic period. During the Middle Preclassic period, substantial formal ceremonial complexes appear to have been built only at a small number of important communities in the Maya lowlands, and groups with different levels of sedentism probably gathered for their constructions and for public rituals held in them. These collaborative activities likely played a central role in socially integrating diverse groups with different lifestyles and, eventually, in developing fully established sedentary communities.


Assuntos
Civilização/história , Comportamento Social , Arqueologia , Arquitetura , América Central , Comportamento Ritualístico , Meio Ambiente , Etnicidade/história , Geografia , Guatemala , História Antiga , Humanos , Indígenas Centro-Americanos/história , Características de Residência
7.
PLoS One ; 9(9): e107982, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25254359

RESUMO

Religious rituals that are painful or highly stressful are hypothesized to be costly signs of commitment essential for the evolution of complex society. Yet few studies have investigated how such extreme ritual practices were culturally transmitted in past societies. Here, we report the first study to analyze temporal and spatial variation in bloodletting rituals recorded in Classic Maya (ca. 250-900 CE) hieroglyphic texts. We also identify the sociopolitical contexts most closely associated with these ancient recorded rituals. Sampling an extensive record of 2,480 hieroglyphic texts, this study identifies every recorded instance of the logographic sign for the word ch'ahb' that is associated with ritual bloodletting. We show that documented rituals exhibit low frequency whose occurrence cannot be predicted by spatial location. Conversely, network ties better capture the distribution of bloodletting rituals across the southern Maya region. Our results indicate that bloodletting rituals by Maya nobles were not uniformly recorded, but were typically documented in association with antagonistic statements and may have signaled royal commitments among connected polities.


Assuntos
Sangria/história , Comportamento Ritualístico , Evolução Cultural , Etnicidade/história , Reconhecimento Automatizado de Padrão , Religião/história , Redação/história , América/etnologia , Sangria/psicologia , Gráficos por Computador , Documentação , Etnicidade/psicologia , História Antiga , Humanos , Modelos Estatísticos
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