Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34400499

RESUMEN

Constraining secular variation of the Earth's magnetic field strength in the past is fundamental to understanding short-term processes of the geodynamo. Such records also constitute a powerful and independent dating tool for archaeological sites and geological formations. In this study, we present 11 robust archaeointensity results from Pre-Pottery to Pottery Neolithic Jordan that are based on both clay and flint (chert) artifacts. Two of these results constitute the oldest archaeointensity data for the entire Levant, ancient Egypt, Turkey, and Mesopotamia, extending the archaeomagnetic reference curve for the Holocene. Virtual Axial Dipole Moments (VADMs) show that the Earth's magnetic field in the Southern Levant was weak (about two-thirds the present field) at around 7600 BCE, recovering its strength to greater than the present field around 7000 BCE, and gradually weakening again around 5200 BCE. In addition, successful results obtained from burnt flint demonstrate the potential of this very common, and yet rarely used, material in archaeomagnetic research, in particular for prehistoric periods from the first use of fire to the invention of pottery.

3.
Bioorg Med Chem Lett ; 40: 127910, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33711443

RESUMEN

Indoleamine 2,3-dioxygenase (IDO1) and tryptophane 2,3-dioxygenase (TDO) are two heme-containing enzymes which catalyze the conversion of tryptophan to N-formylkynurenine. Both enzymes are well establish therapeutic targets as important factors in the tumor immune evasion mechanism. A number of analogues of the marine pyrroloquinoline alkaloids tsitsikammamines or wakayin have been synthesized, two of them were synthesized using an original method to build the bispyrroloquinone framework. All the derivatives were evaluated in a cellular assay for their capacity to inhibit the enzymes. Six compounds have shown a significant potency on HEK 293-EBNA cell lines expressing hIDO1 or hTDO.


Asunto(s)
Alcaloides/síntesis química , Inhibidores Enzimáticos/síntesis química , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Pirroliminoquinonas/síntesis química , Bibliotecas de Moléculas Pequeñas/síntesis química , Triptófano Oxigenasa/antagonistas & inhibidores , Alcaloides/metabolismo , Organismos Acuáticos/química , Inhibidores Enzimáticos/metabolismo , Células HEK293 , Humanos , Alcaloides Indólicos/química , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica , Pirroles/química , Pirroliminoquinonas/metabolismo , Quinolinas/química , Bibliotecas de Moléculas Pequeñas/metabolismo , Relación Estructura-Actividad
5.
Bol Asoc Med P R ; 107(1): 20-4, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26035980

RESUMEN

Chikungunya is a viral illness characterized by severe joint pains, which may persist for months to years. There is no effective treatment for this disease. We treated 56 patients with moderate to severe persistent pains with a single infusion of ascorbic acid ranging from 25-50 grams and hydrogen peroxide (3 cc of a 3% solution) from July to October 2014. Patients were asked about their pain using the Verbal Numerical Rating Scale-11 immediately before and after treatment. The mean Pain Score before and after treatment was 8 and 2 respectively (60%) (p < 0.001); and 5 patients (9%) had a Pain Score of 0. The use of intravenous ascorbic acid and hydrogen peroxide resulted in a statistically significant reduction of pain in patients with moderate to severe pain from the Chikungunya virus immediately after treatment.


Asunto(s)
Ácido Ascórbico/uso terapéutico , Fiebre Chikungunya/tratamiento farmacológico , Peróxido de Hidrógeno/uso terapéutico , Dolor/tratamiento farmacológico , Ácido Ascórbico/administración & dosificación , Femenino , Humanos , Peróxido de Hidrógeno/administración & dosificación , Masculino , Dolor/etiología , Dimensión del Dolor , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
6.
Nature ; 455(7212): 528-31, 2008 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-18690215

RESUMEN

The domestication of cattle, sheep and goats had already taken place in the Near East by the eighth millennium bc. Although there would have been considerable economic and nutritional gains from using these animals for their milk and other products from living animals-that is, traction and wool-the first clear evidence for these appears much later, from the late fifth and fourth millennia bc. Hence, the timing and region in which milking was first practised remain unknown. Organic residues preserved in archaeological pottery have provided direct evidence for the use of milk in the fourth millennium in Britain, and in the sixth millennium in eastern Europe, based on the delta(13)C values of the major fatty acids of milk fat. Here we apply this approach to more than 2,200 pottery vessels from sites in the Near East and southeastern Europe dating from the fifth to the seventh millennia bc. We show that milk was in use by the seventh millennium; this is the earliest direct evidence to date. Milking was particularly important in northwestern Anatolia, pointing to regional differences linked with conditions more favourable to cattle compared to other regions, where sheep and goats were relatively common and milk use less important. The latter is supported by correlations between the fat type and animal bone evidence.


Asunto(s)
Bovinos/fisiología , Industria Lechera/historia , Leche/historia , Leche/estadística & datos numéricos , Animales , Cerámica/análisis , Europa (Continente) , Europa Oriental , Ácidos Grasos/análisis , Cabras , Historia Antigua , Humanos , Carne , Leche/química , Ovinos
7.
Proc Natl Acad Sci U S A ; 105(43): 16460-5, 2008 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-18955702

RESUMEN

Recent excavations and high-precision radiocarbon dating from the largest Iron Age (IA, ca. 1200-500 BCE) copper production center in the southern Levant demonstrate major smelting activities in the region of biblical Edom (southern Jordan) during the 10th and 9th centuries BCE. Stratified radiocarbon samples and artifacts were recorded with precise digital surveying tools linked to a geographic information system developed to control on-site spatial analyses of archaeological finds and model data with innovative visualization tools. The new radiocarbon dates push back by 2 centuries the accepted IA chronology of Edom. Data from Khirbat en-Nahas, and the nearby site of Rujm Hamra Ifdan, demonstrate the centrality of industrial-scale metal production during those centuries traditionally linked closely to political events in Edom's 10th century BCE neighbor ancient Israel. Consequently, the rise of IA Edom is linked to the power vacuum created by the collapse of Late Bronze Age (LB, ca. 1300 BCE) civilizations and the disintegration of the LB Cypriot copper monopoly that dominated the eastern Mediterranean. The methodologies applied to the historical IA archaeology of the Levant have implications for other parts of the world where sacred and historical texts interface with the material record.


Asunto(s)
Arqueología , Radioisótopos de Carbono , Civilización , Historia Antigua , Humanos , Jordania
8.
Science ; 374(6573): 1330, 2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34882440

RESUMEN

Science, politics, identity, and conflict converge in investigations of the city of peace.

9.
PLoS One ; 16(6): e0251870, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34106939

RESUMEN

This article presents new archaeological observations and multidisciplinary research from Dor, Israel to establish a more reliable relative sea level for the Carmel Coast and Southern Levant between the Middle Bronze Age and the Roman period (ca. 3500-1800 y BP). Our record indicates a period of low relative sea level, around -2.5 m below present, from the Middle Bronze Age to the Hellenistic period (ca. 3500-2200 y BP). This was followed by a rapid rise to present levels, starting in the Hellenistic period and concluding during the Roman period (ca. 2200-1800 y BP). These Roman levels agree with other relative sea-level indications from Israel and other tectonically stable areas in the Mediterranean. Several relative sea-level reconstruction models carried out in the current study provide different predictions due to their parameters and do not model the changes observed from field data which points to a non-isostatic origin for the changes. Long-term low stable Iron Age relative sea level can be seen in Dor, where Iron Age harbor structures remain around the same elevation between ca. 3100-2700 y BP. A similar pattern occurs at Atlit, the Iron Age harbor to the north used continuously from ca. 2900 y BP to the beginning of the Hellenistic period (ca. 2200 y BP). An examination of historical and archaeological sources reveals decline and occasional disappearance of Hellenistic sites along the coast of Israel at ca. 2200 y BP (2nd century BCE), as in the case of Yavneh Yam, Ashdod Yam, Straton's Tower, and tel Taninim. In Akko-Ptolemais, the large harbor installations built in the Hellenistic period were never replaced by a substantial Roman harbor. The conclusions of this research are thus relevant for the sea-level research community and for the historical analyses of the Israeli and South Levantine coastline.

11.
PLoS One ; 15(12): e0243619, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33362214

RESUMEN

Tsunami events in antiquity had a profound influence on coastal societies. Six thousand years of historical records and geological data show that tsunamis are a common phenomenon affecting the eastern Mediterranean coastline. However, the possible impact of older tsunamis on prehistoric societies has not been investigated. Here we report, based on optically stimulated luminescence chronology, the earliest documented Holocene tsunami event, between 9.91 to 9.29 ka (kilo-annum), from the eastern Mediterranean at Dor, Israel. Tsunami debris from the early Neolithic is composed of marine sand embedded within fresh-brackish wetland deposits. Global and local sea-level curves for the period, 9.91-9.29 ka, as well as surface elevation reconstructions, show that the tsunami had a run-up of at least ~16 m and traveled between 3.5 to 1.5 km inland from the palaeo-coastline. Submerged slump scars on the continental slope, 16 km west of Dor, point to the nearby "Dor-complex" as a likely cause. The near absence of Pre-Pottery Neolithic A-B archaeological sites (11.70-9.80 cal. ka) suggest these sites were removed by the tsunami, whereas younger, late Pre-Pottery Neolithic B-C (9.25-8.35 cal. ka) and later Pottery-Neolithic sites (8.25-7.80 cal. ka) indicate resettlement following the event. The large run-up of this event highlights the disruptive impact of tsunamis on past societies along the Levantine coast.


Asunto(s)
Tsunamis , Arqueología , Sedimentos Geológicos/análisis , Historia Antigua , Humanos , Israel , Mediciones Luminiscentes , Tsunamis/historia
12.
PLoS One ; 14(9): e0221967, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31532811

RESUMEN

While the punctuated equilibrium model has been employed in paleontological and archaeological research, it has rarely been applied for technological and social evolution in the Holocene. Using metallurgical technologies from the Wadi Arabah (Jordan/Israel) as a case study, we demonstrate a gradual technological development (13th-10th c. BCE) followed by a human agency-triggered punctuated "leap" (late-10th c. BCE) simultaneously across the entire region (an area of ~2000 km2). Here, we present an unparalleled, diachronic archaeometallurgical dataset focusing on elemental analysis of dozens of well-dated slag samples. Based on the results, we suggest punctuated equilibrium provides an innovative theoretical model for exploring ancient technological changes in relation to larger sociopolitical conditions-in the case at hand the emergence of biblical Edom-, exemplifying its potential for more general cross-cultural applications.


Asunto(s)
Cobre/análisis , Metalurgia/historia , Arqueología , Historia Antigua , Humanos , Israel , Jordania , Modelos Teóricos , Paleontología
13.
J Endod ; 38(11): 1484-8, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23063222

RESUMEN

INTRODUCTION: Symptomatic teeth with periradicular lesions of infectious origin remain a significant challenge in dentistry, and the reason for the acute perturbation is incompletely understood. The present study used pyrosequencing of bacterial 16S ribosomal RNA (rRNA) genes to characterize the microbiota of periradicular lesions. METHODS: Thirteen periradicular lesions from 11 symptomatic and 2 asymptomatic teeth were sampled during apical surgery. Samples were subjected to DNA extraction and 16S rRNA polymerase chain reaction (PCR) amplification. PCR amplicons were then sequenced by using the Roche 454 GS FLX platform. Data were analyzed with the Quantitative Insights into Microbial Ecology (QIIME) software package. RESULTS: Seven of the 13 periradicular lesions (53.8%) yielded PCR amplicons, which generated 35,731 high-quality DNA sequences belonging to 10 bacterial phyla and 73 bacterial genera. All 7 lesions were associated with symptoms. The phyla with most bacterial taxa were Proteobacteria (proportion of total bacterial taxa, 33.3%), Firmicutes (30.9%), Actinobacteria (12.2%), and Bacteroidetes (11.4%). The most abundant genera were Fusobacterium (average of total sequences, 21.0%), Streptococcus (8.0%), Prevotella (7.5%), Corynebacterium (7.2%), Porphyromonas (6.0%). and Actinomyces (5.8%). CONCLUSIONS: This study demonstrated that the microbiota of symptomatic periapical lesions is predominated by anaerobic bacteria but also contains substantial levels of streptococci, actinomyces, and bacteria not previously identified in the oral cavity. The etiopathogenic role and therapeutic implication of periradicular bacteria need to be determined.


Asunto(s)
ADN Bacteriano/genética , Cavidad Pulpar/microbiología , Periodontitis Periapical/microbiología , Análisis de Secuencia de ADN/métodos , Humanos , Metagenoma , ARN Ribosómico 16S/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA