52 research outputs found
Re-evaluating the resource potential of lomas fog oasis environments for Preceramic hunter-gatherers under past ENSO modes on the south coast of Peru
Lomas – ephemeral seasonal oases sustained by ocean fogs – were critical to ancient human ecology on the desert Pacific coast of Peru: one of humanity’s few independent hearths of agriculture and “pristine” civilisation. The role of climate change since the Late Pleistocene in determining productivity and extent of past lomas ecosystems has been much debated.
Here we reassess the resource potential of the poorly studied lomas of the south coast of Peru during the long Middle Pre-ceramic period (c. 8,000 – 4,500 BP): a period critical in the transition to agriculture, the onset of modern El Niño Southern Oscillation (‘ENSO’) conditions, and eustatic sea-level rise and stabilisation and beach progradation.
Our method combines vegetation survey and herbarium collection with archaeological survey and excavation to make inferences about both Preceramic hunter-gatherer ecology and the changed palaeoenvironments in which it took place. Our analysis of newly discovered archaeological sites – and their resource context – show how lomas formations defined human ecology until the end of the Middle Preceramic Period, thereby corroborating recent reconstructions of ENSO history based on other data.
Together, these suggest that a five millennia period of significantly colder seas on the south coast induced conditions of abundance and seasonal predictability in lomas and maritime ecosystems, that enabled Middle Preceramic hunter-gatherers to reduce mobility by settling in strategic locations at the confluence of multiple eco-zones at the river estuaries. Here the foundations of agriculture lay in a Broad Spectrum Revolution that unfolded, not through population pressure in deteriorating environments, but rather as an outcome of resource abundance.We thank the Ministerio de Cultural del Perú for granting permission for archaeological fieldwork (Resolución Directoral Nº 933-2012-DGPC-VMPCIC/MC, 19 December 2012 and Nº 386-2014-DGPA-VMPCIC/MC, 22 August 2014) and the export of samples for dating; Don Alberto Benavides Ganoza and the people of Samaca for facilitating fieldwork; the Leverhulme Trust (grant number RPG-117) and the late Don Alberto Benavides de la Quintana (grant number RG69428) and the McDonald Institute for Archaeological Research for funding Cambridge University’s One River Archaeological Project, and the NERC Radiocarbon facility (grant number NF/2013/2/2) for funding radiocarbon dating. We also thank the Servicio Nacional Forestal y de Fauna Silvestre (SERFOR) and the Servicio Nacional de Áreas Naturales Protegidas por el Estado (SERNANP), Peru for permits for the Proyecto Kew Perú to carry out botanical and ecological survey, and Delsy Trujillo, Eric Ramírez, Consuelo Borda and other participants of the Proyecto Kew Perú: Conservación, Restauración de Hábitats y Medios de Vida Útiles, Ica, Peru.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.quascirev.2015.10.02
Cannabinoid CB1 receptor antagonism markedly increases dopamine receptor-mediated stereotypies
The contribution of the endocannabinoid system to dopamine-mediated disorganized behavior in schizophrenia is discussed. We used a model of concurrent stimulation of dopamine D1 and D2 receptors to evaluate the role of this system in dopamine-mediated stereotypies measured in a hole-board test. Pretreatment with the cannabinoid CB1 receptor antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichloro-phenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716A; 1 mg/kg) potentiated stereotyped behavior induced by coadministration of the dopamine D1 receptor agonist SKF 38393 (0.05, 0.1 and 1 mg/kg) and the dopamine D2 receptor agonist quinpirole (0.25 mg/kg). Thus, the endocannabinoid system acts as a brake for abnormal behavior associated with dopaminergic overactivation. © 2007 Elsevier B.V. All rights reserved.Peer Reviewe
Genomic and phenotypic attributes of novel salinivibrios from stromatolites, sediment and water from a high altitude lake
Background: Salinivibrios are moderately halophilic bacteria found in salted meats, brines and hypersaline environments. We obtained three novel conspecific Salinivibrio strains closely related to S. costicola, from Socompa Lake, a high altitude hypersaline Andean lake (approx. 3,570 meters above the sea level).Results: The three novel Salinivibrio spp. were extremely resistant to arsenic (up to 200 mM HAsO42-), NaCl (up to 15%), and UV-B radiation (19 KJ/m2, corresponding to 240 minutes of exposure) by means of phenotypic tests. Our subsequent draft genome ionsequencing and RAST-based genome annotation revealed the presence of genes related to arsenic, NaCl, and UV radiation resistance. The three novel Salinivibrio genomes also had the xanthorhodopsin gene cluster phylogenetically related to Marinobacter and Spiribacter. The genomic taxonomy analysis, including multilocus sequence analysis, average amino acid identity, and genome-to-genome distance revealed that the three novel strains belong to a new Salinivibrio species.Conclusions: Arsenic resistance genes, genes involved in DNA repair, resistance to extreme environmental conditions and the possible light-based energy production, may represent important attributes of the novel salinivibrios, allowing these microbes to thrive in the Socompa Lake. © 2014 Gorriti et al.; licensee BioMed Central Ltd.Fil: Gorriti, Marta Fabiana. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Dias, Graciela M.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Chimetto, Luciane A.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Trindade-Silva, Amaro E.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Silva, Bruno S.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Mesquita, Milene M.A.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Gregoracci, Gustavo B.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Farias, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Thompson, Cristiane C.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; BrasilFil: Thompson, Fabiano L.. Laboratório de Microbiologia, Instituto de Biologia, Universidade Federal do
Rio de Janeiro (UFRJ), Rio de Janeiro, Brasil ; Brasi
Role of the endogenous cannabinoid system as a modulator of dopamine transmission: Implications for Parkinson’s disease and schizophrenia
APOE ɛ4 exacerbates age-dependent deficits in cortical microstructure
The apolipoprotein E ɛ4 allele is the primary genetic risk factor for the sporadic type of Alzheimer’s disease. However, the mechanisms by which apolipoprotein E ɛ4 are associated with neurodegeneration are still poorly understood. We applied the Neurite Orientation Dispersion Model to characterize the effects of apolipoprotein ɛ4 and its interactions with age and education on cortical microstructure in cognitively normal individuals. Data from 1954 participants were included from the PREVENT-Dementia and ALFA (ALzheimer and FAmilies) studies (mean age = 57, 1197 non-carriers and 757 apolipoprotein E ɛ4 carriers). Structural MRI datasets were processed with FreeSurfer v7.2. The Microstructure Diffusion Toolbox was used to derive Orientation Dispersion Index maps from diffusion MRI datasets. Primary analyses were focused on (i) the main effects of apolipoprotein E ɛ4, and (ii) the interactions of apolipoprotein E ɛ4 with age and education on lobar and vertex-wise Orientation Dispersion Index and implemented using Permutation Analysis of Linear Models. There were apolipoprotein E ɛ4 × age interactions in the temporo-parietal and frontal lobes, indicating steeper age-dependent Orientation Dispersion Index changes in apolipoprotein E ɛ4 carriers. Steeper age-related Orientation Dispersion Index declines were observed among apolipoprotein E ɛ4 carriers with lower years of education. We demonstrated that apolipoprotein E ɛ4 worsened age-related Orientation Dispersion Index decreases in brain regions typically associated with atrophy patterns of Alzheimer’s disease. This finding also suggests that apolipoprotein E ɛ4 may hasten the onset age of dementia by accelerating age-dependent reductions in cortical Orientation Dispersion Index
The molecular logic of endocannabinoid signalling
The endocannabinoids are a family of lipid messengers that engage the cell surface receptors that are targeted by Δ9-tetrahydrocannabinol, the active principle in marijuana (Cannabis). They are made on demand through cleavage of membrane precursors and are involved in various short-range signalling processes. In the brain, they combine with CB1 cannabinoid receptors on axon terminals to regulate ion channel activity and neurotransmitter release. Their ability to modulate synaptic efficacy has a wide range of functional consequences and provides unique therapeutic possibilities. © 2003, Nature Publishing Group. All rights reserved
Aprendizaje basado en problemas: una aplicación práctica en la enseñanza de materiales
En el presente trabajo se presenta el diseño de un ABP, aprendizaje basado en problemas, de aplicación en la enseñanza de Propiedades de los Materiales de la asignatura de Fundamentos de Materiales I del primer curso del Grado de Arquitectura Técnica. Con la utilización de esta metodología didáctica se pretende, por una parte, mejorar la calidad del aprendizaje y trabajar no sólo las competencias específicas del grado sino que también las enfocadas a la consecución de habilidades de trabajo en equipo y comunicativas, y por otra, aumentar la motivación del alumno por la asignatura.SIN FINANCIACIÓNNo data 201
Motivación y creatividad en la formación universitaria
En esta ponencia se presentan y analizan los resultados de la experiencia de dos metodologías y herramientas didácticas puestas en práctica en la enseñanza de Fundamentos de Materiales I, asignatura de primer curso del Grado de Arquitectura Técnica. Por una parte, de la utilización de un ABP, aprendizaje basado en problemas, como alternativa al método tradicional de enseñanza, en el cual el docente explica una parte de la materia y seguidamente propone a los alumnos una actividad de aplicación de dichos contenidos, y por otra, de la utilización de herramientas informáticas como instrumentos de utilidad no sólo en la adquisición de conocimientos, sino que también como forma de fomentar el desarrollo de la creatividad.SIN FINANCIACIÓNNo data 201
Foros virtuales. Una herramienta e-Learning para fomentar la interactividad y aprendizaje colaborativo
En los últimos años en la docencia se está dando gran importancia a lo que se ha venido en llamar "aprendizaje colaborativo" y una de las causas es la revolución tecnológica que aboga por entornos de aprendizaje virtuales y globales. Dentro de estos entornos, los foros didácticos ponen en red simultáneamente a muchas personas, proporcionando una característica muy importante para el aprendizaje: la interactividad En este trabajo se ha utilizado, dentro de la plataforma virtual e-Gela una herramienta de comunicación e-Learning, el foro, para reforzar contenidos curriculares. En este sentido el foro se constituye como el medio para que el alumno plantee sus dudas, y sean sus propios compañeros quienes se las resuelvan. El objetivo de este estudio es sistematizar y mostrar la utilidad del foro para resolver dudas, desde la percepción y experiencia de los estudiantes. A partir de esta información y experiencia se pretende que los docentes consideren incorporar un foro de dudas en su asignatura.SIN FINANCIACIÓNNo data 201
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Reversal of dopamine D(2) receptor responses by an anandamide transport inhibitor.
We characterized the pharmacological properties of the anandamide transport inhibitor N-(4-hydroxyphenyl)-arachidonamide (AM404) in rats and investigated the effects of this drug on behavioral responses associated with activation of dopamine D(2) family receptors. Rat brain slices accumulated [(3)H]anandamide via a high-affinity transport mechanism that was blocked by AM404. When administered alone in vivo, AM404 caused a mild and slow-developing hypokinesia that was significant 60 min after intracerebroventricular injection of the drug and was reversed by the CB1 cannabinoid receptor antagonist SR141716A. AM404 produced no significant catalepsy or analgesia, two typical effects of direct-acting cannabinoid agonists. However, AM404 prevented the stereotypic yawning produced by systemic administration of a low dose of apomorphine, an effect that was dose-dependent and blocked by SR141716A. Furthermore, AM404 reduced the stimulation of motor behaviors elicited by the selective D(2) family receptor agonist quinpirole. Finally, AM404 reduced hyperactivity in juvenile spontaneously hypertensive rats, a putative model of attention deficit hyperactivity disorder. The results support a primary role of the endocannabinoid system in the regulation of psychomotor activity and point to anandamide transport as a potential target for neuropsychiatric medicines
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