6,442 research outputs found
Dressed States Approach to Quantum Systems
Using the non-perturbative method of {\it dressed} states previously
introduced in JPhysA, we study effects of the environment on a quantum
mechanical system, in the case the environment is modeled by an ensemble of non
interacting harmonic oscillators. This method allows to separate the whole
system into the {\it dressed} mechanical system and the {\it dressed}
environment, in terms of which an exact, non-perturbative approach is possible.
When applied to the Brownian motion, we give explicit non-perturbative formulas
for the classical path of the particle in the weak and strong coupling regimes.
When applied to study atomic behaviours in cavities, the method accounts very
precisely for experimentally observed inhibition of atomic decay in small
cavities PhysLA, physics0111042
Los sistemas de pago por servicios ambientales entre la adicionalidad y la subsidiariedad: aplicación a la belleza escénica en el pantano de San Juan, Madrid, España
A payment for environmental services (PES) based on the beauty of the San Juan dam landscape is proposed containing two innovative aspect in regard to previous PES systems: the elaboration of a diagnosis oriented to obtain a shared vision of the area based in a participative process including all relevant local stakeholders, and the integration of the PES mechanism into the regional public environmental policy. The proposed system also identifies the offer and the demand of the environmental service. It shows the main problems associated to the preservation of the service and proposes management plans oriented to its conservation. Finally, the economic viability of the system is studied comparing three different scenarios according to the grade of integration of the PES model into the regional conservation public policy. This paper shows how a PES system can be used to guarantee public investments in nature conservation through a private management.Se plantea un sistema de pago por servicios ambientales (PSA) basado en la valoración de la belleza escénica en la
zona del pantano de San Juan, Madrid, con dos aspectos novedosos respecto a estudios PSA previos: la elaboración de un diagnóstico basado en un proceso participativo que involucra a todos los actores sociales locales y cuyo fin es el de obtener una visión compartida sobre el área, y la integración del mecanismo PSA en la gestión pública regional de la conservación de la naturaleza. El sistema propuesto además identifica los oferentes y demandantes del servicio ambiental, muestra los principales problemas asociados a la conservación del servicio y plantea programas de gestión orientados a contribuir a su conservación. Se estudia, por último, la viabilidad económica del sistema comparando tres escenarios hipotéticos en función del grado de integración del sistema PSA en las políticas públicas de conservación de la naturaleza regionales. El trabajo muestra como un sistema PSA puede servir para garantizar las inversiones públicas en conservación a través de la gestión privada
Monocyte Subsets and Serum Inflammatory and Bone-Associated Markers in Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma
© 2021 by the authors.Monocyte/macrophages have been shown to be altered in monoclonal gammopathy of undetermined significance (MGUS), smoldering (SMM) and active multiple myeloma (MM), with an impact on the disruption of the homeostasis of the normal bone marrow (BM) microenvironment.This research was funded by the Biomedical Research Networking Center Consortium CIBER-CIBERONC (CB16/12/00400, CB16/12/00369 and CB16/12/00233-FEDER), PI13/01412- FEDER, from the Instituto de Salud Carlos III (ISCIII), Ministerio de Economía y Competitividad, Madrid, Spain; the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement ERC-2015-AdG 695655 (TiMaScan); and the Black Swan Research Initiative of the International Myeloma Foundation (Los Angeles, CA, USA), (grant IMF13/IMF16
Nuevas fuentes de antioxidantes naturales: caracterización de compuestos bioactivos en cinco frutos nativos de Chile.
Diferentes berries de la zona centro y sur de Chile fueron analizados con el fin de buscar fuentes promisorias de polifenoles con clara actividad sobre la salud humana. Se estudiaron cinco bayas nativas: arrayan, frutilla blanca, murtilla y calafate, y un berry tradicional (uva tintorera). Se determinó in vitro sus propiedades antioxidantes según el ensayo de polifenoles totales de Folin Ciocalteu, antocianinas por pH diferencial, capacidad antioxidante por medición de capacidad de reducción del radical libre 2.2-difenil-1picrilhidracilo (DPPH) y poder de reducción férrica (FRAP) y perfil químico por HPLC-DAD. De los cinco berries, calafate registró el valor más alto (1066,4 ± 24,9 mg GAE/100g de muestra) para polifenoles totales y antocianinas (1031,9 ± 48,1 mg de cianidina-3-glucósido/100g de muestra) seguido por uva tintorera. Calafate presentó excelente poder reductor (11279,2 ± 2027,4 umol Trolox/100g ensayo FRAP y 5235,0 ± 445,9, umol/100g en PPH). El perfil químico de antocianinas mostró delfinidina, cianidina, malvidina, petunidina, peonidina y pelargonidina en los cinco berries. Alrededor de 30 flavonoles derivados de quercetina, myricetina e isorhamnetina fueron identificados así cómo elagitaninos presentes en frutilla blanca, compuestos muy interesantes para estudios posteriores. Estos resultados contribuyen a destacar el uso potencial de estos berries como alimentos funcionales.Berries from central and southern Chile were analyzed in order to find promising sources of polyphenols with clear activity on human health. Five native fruits like arrayan, white strawberry, murtilla and calafate, and a traditional berry (grape called “tintorera”) were studied. Antioxidant properties were determined in vitro according to the total polyphenol assay of Folin Ciocalteu, anthocyanins by differential pH, antioxidant capacity by measuring the capacity of reduction of the free radical 2.2-diphenyl-1-picrylhydracil (DPPH) and iron reducing capacity (FRAP) and chemical profile by HPLC-DAD. Calafate showed the highest value (1066.4 ± 24.9 mg gallic acid / 100g sample) for total polyphenols and anthocyanins (1031.9 ± 48.1 mg of cyanidin-3-glucoside / 100g of sample) followed by blue grape. Calafate displayed excellent reducing power (11279.2 ± 2027.4 umol Trolox / 100g FRAP assay and 5235.0 ± 445.9, umol / 100g in DPPH), followed by grape. The chemical profile ofanthocyanins showed delphinidin, cyanidin, malvidin, petunidin, peonidin and pelargonidin in the five berries. Around 30 flavonols derived from quercetin, yricetin and sorhamnetin were identified as well as ellagitannins present in white trawberry, very interesting compounds for further studies. These results contribute to highlight the potential use of these berries as functional foods
Oxidative Stress and Parkinson’s Disease: Effects on Environmental Toxicology
Epidemiological studies have found an increased risk of Parkinson’s disease (PD) with environmental factors such as exposure to substances derived from industrial processes, use of agrochemicals, or living in a rural environment. The hypothesis that certain environmental toxins could be the source of the EP is supported by the discovery that chemicals such as herbicides paraquat, diquat, and the fungicide maneb are selectively toxic in nigrostriatal dopaminergic neurons. Also, one of the insecticides produced by plants, such as rotenone, and by-product of the synthesis of synthetic heroin MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) can be reproduced in animal models where neurochemicals, histopathological, and clinical characteristic of PD can be found. Interestingly, there are similarities in the chemical structure of paraquat and MPTP. Recent evidence exhibited that inflammation and oxidative stress play an essential role in the development of PD. So, in our laboratory we found that in an animal model melatonin decreases the products of lipid oxidation, nitric oxide metabolites, and the activity of cyclooxygenase 2, which are induced by an intraperitoneal injection of MPTP. This suggests that the neuroprotective effects of melatonin are partially attributed to its antioxidant scavenging and anti-inflammatory action
Validating Measures of Third Year Medical Students’ Use of Interpreters by Standardized Patients and Faculty Observers
Next generation flow for minimally-invasive blood characterization of MGUS and multiple myeloma at diagnosis based on circulating tumor plasma cells (CTPC)
Here, we investigated for the first time the frequency and number of circulating tumor plasma cells (CTPC) in peripheral blood (PB) of newly diagnosed patients with localized and systemic plasma cell neoplasms (PCN) using next-generation flow cytometry (NGF) and correlated our findings with the distinct diagnostic and prognostic categories of the disease. Overall, 508 samples from 264 newly diagnosed PCN patients, were studied. CTPC were detected in PB of all active multiple myeloma (MM; 100%), and smoldering MM (SMM) patients (100%), and in more than half (59%) monoclonal gammopathy of undetermined significance (MGUS) cases (p < 0.0001); in contrast, CTPC were present in a small fraction of solitary plasmacytoma patients (18%). Higher numbers of CTPC in PB were associated with higher levels of BM infiltration and more adverse prognostic features, together with shorter time to progression from MGUS to MM (p < 0.0001) and a shorter survival in MM patients with active disease requiring treatment (p <= 0.03). In summary, the presence of CTPC in PB as assessed by NGF at diagnosis, emerges as a hallmark of disseminated PCN, higher numbers of PB CTPC being strongly associated with a malignant disease behavior and a poorer outcome of both MGUS and MM
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