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1.
Proc Natl Acad Sci U S A ; 115(35): 8740-8745, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30104352

RESUMO

Hundreds of scarlet macaw (Ara macao cyanoptera) skeletons have been recovered from archaeological contexts in the southwestern United States and northwestern Mexico (SW/NW). The location of these skeletons, >1,000 km outside their Neotropical endemic range, has suggested a far-reaching pre-Hispanic acquisition network. Clear evidence for scarlet macaw breeding within this network is only known from the settlement of Paquimé in NW dating between 1250 and 1450 CE. Although some scholars have speculated on the probable existence of earlier breeding centers in the SW/NW region, there has been no supporting evidence. In this study, we performed an ancient DNA analysis of scarlet macaws recovered from archaeological sites in Chaco Canyon and the contemporaneous Mimbres area of New Mexico. All samples were directly radiocarbon dated between 900 and 1200 CE. We reconstructed complete or near-complete mitochondrial genome sequences of 14 scarlet macaws from five different sites. We observed remarkably low genetic diversity in this sample, consistent with breeding of a small founder population translocated outside their natural range. Phylogeographic comparisons of our ancient DNA mitogenomes with mitochondrial sequences from macaws collected during the last 200 years from their endemic Neotropical range identified genetic affinity between the ancient macaws and a single rare haplogroup (Haplo6) observed only among wild macaws in Mexico and northern Guatemala. Our results suggest that people at an undiscovered pre-Hispanic settlement dating between 900 and 1200 CE managed a macaw breeding colony outside their endemic range and distributed these symbolically important birds through the SW.


Assuntos
Cruzamento , Fósseis , Modelos Biológicos , Papagaios/fisiologia , Animais , Filogeografia , Sudoeste dos Estados Unidos
2.
Proc Natl Acad Sci U S A ; 112(27): 8238-43, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26100874

RESUMO

High-precision accelerator mass spectrometer (AMS) (14)C dates of scarlet macaw (Ara macao) skeletal remains provide the first direct evidence from Chaco Canyon in northwestern New Mexico that these Neotropical birds were procured from Mesoamerica by Pueblo people as early as ∼ A.D. 900-975. Chaco was a prominent prehistoric Pueblo center with a dense concentration of multistoried great houses constructed from the 9th through early 12th centuries. At the best known great house of Pueblo Bonito, unusual burial crypts and significant quantities of exotic and symbolically important materials, including scarlet macaws, turquoise, marine shell, and cacao, suggest societal complexity unprecedented elsewhere in the Puebloan world. Scarlet macaws are known markers of social and political status among the Pueblos. New AMS (14)C-dated scarlet macaw remains from Pueblo Bonito demonstrate that these birds were acquired persistently from Mesoamerica between A.D. 900 and 1150. Most of the macaws date before the hypothesized apogeal Chacoan period (A.D. 1040-1110) to which they are commonly attributed. The 10th century acquisition of these birds is consistent with the hypothesis that more formalized status hierarchies developed with significant connections to Mesoamerica before the post-A.D. 1040 architectural florescence in Chaco Canyon.


Assuntos
Fósseis , Papagaios/metabolismo , Esqueleto , Meio Social , Animais , Arqueologia/métodos , Osso e Ossos/metabolismo , Radioisótopos de Carbono , Ecossistema , Geografia , Humanos , Espectrometria de Massas/métodos , Modelos Teóricos , Datação Radiométrica , Fatores de Tempo
3.
Proc Natl Acad Sci U S A ; 113(5): 1118-20, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26677872
4.
Eye (Lond) ; 38(1): 95-102, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37369766

RESUMO

OBJECTIVE: To compare long-term effectiveness of Standard (UV intensity: 3 mW/cm2, duration: 30 min) vs Accelerated (UV intensity: 9 mW/cm2, duration: 10 min) corneal cross-linking (CXL) for stabilising keratoconus. METHODS: Data for this observational study were captured through a web-based registry system from the routine clinical practice (15 sites across Australia, New Zealand and Italy). The outcomes were compared using mixed-effects regression models. A total of 100 eyes (75 patients) who had standard CXL and 76 eyes (66 patients) who had accelerated CXL, with a follow-up visit at five-year post-CXL were included. RESULTS: Both CXL protocols were effective and safe in stabilising keratoconus and improving outcomes. The adjusted mean changes (95% CI) in outcomes were better in standard CXL than in accelerated CXL [visual acuity gain, 10.2 (7.9-12.5) vs 4.9 (1.6-8.2) logMAR letters; pinhole visual acuity 5.7 (3.5-7.8) vs 0.2 (-2.2 to 2.5) logMAR letters; Kmax -1.8 (-4.3 to 0.6) vs 1.2 (-1.5 to 3.9)D; K2 -0.9 (-2.2 to 0.3) vs 0.1 (-1.3 to 1.6)D; MCT -3.0 (-13.7 to 7.7) vs -11.8 (-23.9 to 0.4) µm (p values for visual acuity, pinhole visual acuity, Kmax: <0.05; for K2 and MCT: >0.05)]. The frequency of adverse events at the 5-year follow-up visit was low in both groups [standard, 5 (5%; haze 3; scarring 1, epithelial defect 1) and accelerated 3 (3.9%; haze 2, scarring 1)]. CONCLUSIONS: Both standard and accelerated CXL were safe and effective procedures for stabilising keratoconus in the long term. The standard CXL resulted in greater improvements in visual acuity and keratometry.


Assuntos
Ceratocone , Fotoquimioterapia , Humanos , Ceratocone/tratamento farmacológico , Crosslinking Corneano , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Riboflavina/uso terapêutico , Raios Ultravioleta , Cicatriz , Colágeno/uso terapêutico , Reagentes de Ligações Cruzadas/uso terapêutico , Sistema de Registros , Topografia da Córnea/métodos , Seguimentos
5.
PLoS One ; 13(6): e0198290, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902207

RESUMO

Questions about how archaeological populations obtained basic food supplies are often difficult to answer. The application of specialist techniques from non-archaeological fields typically expands our knowledge base, but can be detrimental to cultural interpretations if employed incorrectly, resulting in problematic datasets and erroneous conclusions not easily caught by the recipient archaeological community. One area where this problem has failed to find resolution is Chaco Canyon, New Mexico, the center of one of the New World's most vibrant ancient civilizations. Discussions of agricultural feasibility and its impact on local population levels at Chaco Canyon have been heavily influenced by studies of soil salinity. A number of researchers have argued that salinized soils severely limited local agricultural production, instead suggesting food was imported from distant sources, specifically the Chuska Mountains. A careful reassessment of existing salinity data as measured by electrical conductivity reveals critical errors in data conversion and presentation that have misrepresented the character of the area's soil and its potential impact on crops. We combine all available electrical conductivity data, including our own, and apply multiple established conversion methods in order to estimate soil salinity values and evaluate their relationship to agricultural productivity potential. Our results show that Chacoan soils display the same salinity ranges and spatial variability as soils in other documented, productive fields in semi-arid areas. Additionally, the proposed large-scale importation of food from the Chuska Mountains region has serious social implications that have not been thoroughly explored. We consider these factors and conclude that the high cost and extreme inflexibility of such a system, in combination with material evidence for local agriculture within Chaco Canyon, make this scenario highly unlikely. Both the soil salinity and archaeological data suggest that there is no justification for precluding the practice of local agriculture within Chaco Canyon.


Assuntos
Agricultura/história , Solo/química , Arqueologia , Civilização , Produtos Agrícolas/crescimento & desenvolvimento , História Antiga , New Mexico , Salinidade
6.
Nat Commun ; 8: 14115, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28221340

RESUMO

For societies with writing systems, hereditary leadership is documented as one of the hallmarks of early political complexity and governance. In contrast, it is unknown whether hereditary succession played a role in the early formation of prehistoric complex societies that lacked writing. Here we use an archaeogenomic approach to identify an elite matriline that persisted between 800 and 1130 CE in Chaco Canyon, the centre of an expansive prehistoric complex society in the Southwestern United States. We show that nine individuals buried in an elite crypt at Pueblo Bonito, the largest structure in the canyon, have identical mitochondrial genomes. Analyses of nuclear genome data from six samples with the highest DNA preservation demonstrate mother-daughter and grandmother-grandson relationships, evidence for a multigenerational matrilineal descent group. Together, these results demonstrate the persistence of an elite matriline in Chaco for ∼330 years.


Assuntos
Arqueologia/métodos , DNA Mitocondrial/genética , Fósseis , Genômica/métodos , Indígenas Norte-Americanos/genética , Sepultamento , DNA Mitocondrial/química , Feminino , Geografia , Haplótipos , Humanos , Masculino , New Mexico , Linhagem , Datação Radiométrica , Análise de Sequência de DNA
7.
Orbit ; 23(4): 241-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15590526

RESUMO

PURPOSE: To report a case of poliosis arising from treatment with topical medications. DESIGN: Interventional case report. METHODS: A 37-year-old man was treated for fungal endophthalmitis arising from Aspergillus fumigatus keratitis with penetrating keratoplasty, lensectomy and vitrectomy together with systemic and prolonged topical medications. RESULTS: Recovery was complicated by retinal detachment, elevated intraocular pressure and bullous keratopathy. Unilateral poliosis developed eight months following keratoplasty and has persisted over 2(1)/(2) years. CONCLUSIONS: Topical medications are implicated in causing the poliosis.


Assuntos
Anti-Hipertensivos/efeitos adversos , Aspergilose/tratamento farmacológico , Endoftalmite/tratamento farmacológico , Pestanas/efeitos dos fármacos , Doenças do Cabelo/induzido quimicamente , Transtornos da Pigmentação/induzido quimicamente , Prostaglandinas F Sintéticas/efeitos adversos , Adulto , Aspergilose/microbiologia , Econazol/uso terapêutico , Endoftalmite/microbiologia , Infecções Oculares Fúngicas/tratamento farmacológico , Infecções Oculares Fúngicas/microbiologia , Humanos , Pressão Intraocular/efeitos dos fármacos , Ceratite/tratamento farmacológico , Ceratite/microbiologia , Ceratoplastia Penetrante , Latanoprosta , Masculino
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