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  1 / 31214 MEDLINE  
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PMID:29268104
Autor:Geng C; Bergheaud V; Garnier P; Zhu YG; Haudin CS
Endereço:UMR ECOSYS, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France; Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 361021, Xiamen, China.
Título:Impact of sludge treatments on the extractability and fate of acetyl sulfamethoxazole residues in amended soils.
Fonte:Chemosphere; 194:828-836, 2018 Mar.
ISSN:1879-1298
País de publicação:England
Idioma:eng
Resumo:Sludge recycled in agriculture may bring antibiotics into cropped soils. The nature, total amount, and availability of the antibiotics in soil partly depend on the sludge treatments. Our paper compares the fate of N-acetyl sulfamethoxazole (AC-SMX) residues between soils incubated with the same sludge but submitted to different processes before being added in soil. The fate of C-AC-SMX residues was studied in mixtures of soil and sludges at different treatment levels: 1) activated and 2) centrifuged sludges, both enriched with C-AC-SMX, and 3) limed and 4) heat-dried sludges obtained by treating the previously contaminated centrifuged sludge. The evolution of the extractability of C residues (CaCl , methanol) and their mineralization were followed during 119 days. More than 80% of the initial C-activity was no longer extractable after 14 days, except in soil with limed sludge. Liming and drying the centrifuged sludge decreased the mineralized C fraction from 5.7-6.4% to 1.2-1.8% and consequently, the corresponding soils contained more C residues after 119 days. Although C residues were more CaCl -extractable in soil with limed sludge, they seemed to be poorly bioavailable for biodegradation. For all solid sludges, the mineralization rate of C-AC-SMX residues was strongly correlated to that of sludge organic carbon, with a coefficient three times lower for the limed and dried sludges than for the centrifuged sludge after 14 days.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Anti-Infective Agents); 0 (Calcium Compounds); 0 (Carbon Radioisotopes); 0 (Minerals); 0 (Oxides); 0 (Sewage); 0 (Soil); 0 (Soil Pollutants); C7X2M0VVNH (lime); JE42381TNV (Sulfamethoxazole)


  2 / 31214 MEDLINE  
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PMID:29351329
Autor:Carleton WC; Campbell D; Collard M
Endereço:Department of Archaeology, Simon Fraser University,University Drive, Burnaby, British Columbia, Canada.
Título:Radiocarbon dating uncertainty and the reliability of the PEWMA method of time-series analysis for research on long-term human-environment interaction.
Fonte:PLoS One; 13(1):e0191055, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Statistical time-series analysis has the potential to improve our understanding of human-environment interaction in deep time. However, radiocarbon dating-the most common chronometric technique in archaeological and palaeoenvironmental research-creates challenges for established statistical methods. The methods assume that observations in a time-series are precisely dated, but this assumption is often violated when calibrated radiocarbon dates are used because they usually have highly irregular uncertainties. As a result, it is unclear whether the methods can be reliably used on radiocarbon-dated time-series. With this in mind, we conducted a large simulation study to investigate the impact of chronological uncertainty on a potentially useful time-series method. The method is a type of regression involving a prediction algorithm called the Poisson Exponentially Weighted Moving Average (PEMWA). It is designed for use with count time-series data, which makes it applicable to a wide range of questions about human-environment interaction in deep time. Our simulations suggest that the PEWMA method can often correctly identify relationships between time-series despite chronological uncertainty. When two time-series are correlated with a coefficient of 0.25, the method is able to identify that relationship correctly 20-30% of the time, providing the time-series contain low noise levels. With correlations of around 0.5, it is capable of correctly identifying correlations despite chronological uncertainty more than 90% of the time. While further testing is desirable, these findings indicate that the method can be used to test hypotheses about long-term human-environment interaction with a reasonable degree of confidence.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Carbon Radioisotopes)


  3 / 31214 MEDLINE  
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PMID:28742952
Autor:Schwartz FW; Liu G; Aggarwal P; Schwartz CM
Endereço:School of Earth Sciences, The Ohio State University, Columbus, OH, 43210.
Título:Naïve Simplicity: The Overlooked Piece of the Complexity-Simplicity Paradigm.
Fonte:Ground Water; 55(5):703-711, 2017 09.
ISSN:1745-6584
País de publicação:United States
Idioma:eng
Resumo:Concepts of simplicity and complexity in modeling have been explored in papers, editorials, and talks. The concept is not well understood because there are at least two flavors of simplicity. Modelers envision simplicity (i.e., elegant simplicity) as the sought-after goal in modeling, but naïve simplicity, which is the focus of this paper, is commonly unrecognized and dangerous. The problem is that naïve or simple ideas are often mistaken for settled science and come with the prospect of being more wrong than right. The concept of the so-called simplicity cycle, in relation to classical problems of carbon-14 age and salinity in closed-basin lakes, is used to illustrate these points. The emerging problems of water-mosquitoes-diseases show the value of mapping new problems to the simplicity cycle. Researchers can "know what they do not know" and avoid the dangers of naïve simplicity.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
Nome de substância:0 (Carbon Radioisotopes); 059QF0KO0R (Water)


  4 / 31214 MEDLINE  
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PMID:29220382
Autor:Ishii T; Kimura Y; Ichise M; Takahata K; Kitamura S; Moriguchi S; Kubota M; Zhang MR; Yamada M; Higuchi M; Okubo Y; Suhara T
Endereço:Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan.
Título:Anatomical relationships between serotonin 5-HT2A and dopamine D2 receptors in living human brain.
Fonte:PLoS One; 12(12):e0189318, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:METHODS: Seven healthy volunteers underwent PET scans with [18F]altanserin and [11C]FLB 457 for 5-HT2A and D2 receptors, respectively. As a measure of receptor density, a binding potential (BP) was calculated from PET data for 76 cerebral cortical regions. A correlation matrix was calculated between the binding potentials of [18F]altanserin and [11C]FLB 457 for those regions. The regional relationships were investigated using a bicluster analysis of the correlation matrix with an iterative signature algorithm. RESULTS: We identified two clusters of regions. The first cluster identified a distinct profile of correlation coefficients between 5-HT2A and D2 receptors, with the former in regions related to sensorimotor integration (supplementary motor area, superior parietal gyrus, and paracentral lobule) and the latter in most cortical regions. The second cluster identified another distinct profile of correlation coefficients between 5-HT2A receptors in the bilateral hippocampi and D2 receptors in most cortical regions. CONCLUSIONS: The observation of two distinct clusters in the correlation matrix suggests regional interactions between 5-HT2A and D2 receptors in sensorimotor integration and hippocampal function. A bicluster analysis of the correlation matrix of these neuroreceptors may be beneficial in understanding molecular networks in the human brain.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes); 0 (Fluorine Radioisotopes); 0 (Receptor, Serotonin, 5-HT2A); 0 (Receptors, Dopamine D2)


  5 / 31214 MEDLINE  
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PMID:29053775
Autor:Datta G; Colasanti A; Rabiner EA; Gunn RN; Malik O; Ciccarelli O; Nicholas R; Van Vlierberghe E; Van Hecke W; Searle G; Santos-Ribeiro A; Matthews PM
Endereço:Division of Brain Sciences, Imperial College London, UK.
Título:Neuroinflammation and its relationship to changes in brain volume and white matter lesions in multiple sclerosis.
Fonte:Brain; 140(11):2927-2938, 2017 Nov 01.
ISSN:1460-2156
País de publicação:England
Idioma:eng
Resumo:Brain magnetic resonance imaging is an important tool in the diagnosis and monitoring of multiple sclerosis patients. However, magnetic resonance imaging alone provides limited information for predicting an individual patient's disability progression. In part, this is because magnetic resonance imaging lacks sensitivity and specificity for detecting chronic diffuse and multi-focal inflammation mediated by activated microglia/macrophages. The aim of this study was to test for an association between 18 kDa translocator protein brain positron emission tomography signal, which arises largely from microglial activation, and measures of subsequent disease progression in multiple sclerosis patients. Twenty-one patients with multiple sclerosis (seven with secondary progressive disease and 14 with a relapsing remitting disease course) underwent T1- and T2-weighted and magnetization transfer magnetic resonance imaging at baseline and after 1 year. Positron emission tomography scanning with the translocator protein radioligand 11C-PBR28 was performed at baseline. Brain tissue and lesion volumes were segmented from the T1- and T2-weighted magnetic resonance imaging and relative 11C-PBR28 uptake in the normal-appearing white matter was estimated as a distribution volume ratio with respect to a caudate pseudo-reference region. Normal-appearing white matter distribution volume ratio at baseline was correlated with enlarging T2-hyperintense lesion volumes over the subsequent year (ρ = 0.59, P = 0.01). A post hoc analysis showed that this association reflected behaviour in the subgroup of relapsing remitting patients (ρ = 0.74, P = 0.008). By contrast, in the subgroup of secondary progressive patients, microglial activation at baseline was correlated with later progression of brain atrophy (ρ = 0.86, P = 0.04). A regression model including the baseline normal-appearing white matter distribution volume ratio, T2 lesion volume and normal-appearing white matter magnetization transfer ratio for all of the patients combined explained over 90% of the variance in enlarging lesion volume over the subsequent 1 year. Glial activation in white matter assessed by translocator protein PET significantly improves predictions of white matter lesion enlargement in relapsing remitting patients and is associated with greater brain atrophy in secondary progressive disease over a period of short term follow-up.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Acetamides); 0 (Carbon Radioisotopes); 0 (N-(2-methoxybenzyl)-N-(4-phenoxypyridin-3-yl)acetamide); 0 (Pyridines); 0 (Receptors, GABA); 0 (TSPO protein, human)


  6 / 31214 MEDLINE  
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PMID:28980836
Autor:Franzese C; Lopci E; Di Brina L; D'Agostino GR; Navarria P; Mancosu P; Tomatis S; Chiti A; Scorsetti M
Endereço:a Radiotherapy and Radiosurgery , Humanitas Clinical and Research Center , Via Manzoni Rozzano ( Milano ) - Italy.
Título:11C-Choline-Pet Guided Stereotactic Body Radiation Therapy for Lymph Node Metastases in Oligometastatic Prostate Cancer.
Fonte:Cancer Invest; 35(9):586-593, 2017 Oct 21.
ISSN:1532-4192
País de publicação:England
Idioma:eng
Resumo:INTRODUCTION: aim is outcome of 11C-Choline-PET guided SBRT on lymph node metastases. MATERIALS AND METHODS: patients with 1 - 4 lymph node metastases detected by 11C-choline-PET were treated with SBRT. Toxicity, treated metastases control and Progression Free Survival were computed. RESULTS: twenty-six patients, 38 lymph node metastases were irradiated. No grade ≥ 2 toxicity. Median PSA-nadir after RT was 1.02 ng/mL. Post-treatment 11C-Choline-PET showed metabolic complete response in 17 metastases (44,7%), partial response in 9 metastases (38%). CONCLUSION: SBRT is effective and safe for lymph node metastases. PET is important in identification of gross tumor and evaluation of the response.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes); 0 (Radiopharmaceuticals); EC 3.4.21.- (Kallikreins); EC 3.4.21.- (kallikrein-related peptidase 3, human); EC 3.4.21.77 (Prostate-Specific Antigen); N91BDP6H0X (Choline)


  7 / 31214 MEDLINE  
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PMID:28854268
Autor:Stewart JAE; Wright DH; Heckman KA
Endereço:Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, United States of America.
Título:Apparent climate-mediated loss and fragmentation of core habitat of the American pika in the Northern Sierra Nevada, California, USA.
Fonte:PLoS One; 12(8):e0181834, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Contemporary climate change has been widely documented as the apparent cause of range contraction at the edge of many species distributions but documentation of climate change as a cause of extirpation and fragmentation of the interior of a species' core habitat has been lacking. Here, we report the extirpation of the American pika (Ochotona princeps), a temperature-sensitive small mammal, from a 165-km2 area located within its core habitat in California's Sierra Nevada mountains. While sites surrounding the area still maintain pikas, radiocarbon analyses of pika fecal pellets recovered within this area indicate that former patch occupancy ranges from before 1955, the beginning of the atmospheric spike in radiocarbon associated with above ground atomic bomb testing, to c. 1991. Despite an abundance of suitable rocky habitat climate warming appears to have precipitated their demise. Weather station data reveal a 1.9°C rise in local temperature and a significant decline in snowpack over the period of record, 1910-2015, pushing pika habitat into increasingly tenuous climate conditions during the period of extirpation. This is among the first accounts of an apparently climate-mediated, modern extirpation of a species from an interior portion of its geographic distribution, resulting in habitat fragmentation, and is the largest area yet reported for a modern-era pika extirpation. Our finding provides empirical support to model projections, indicating that even core areas of species habitat are vulnerable to climate change within a timeframe of decades.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes)


  8 / 31214 MEDLINE  
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PMID:28854234
Autor:Holdaway SJ; Fanning PC; Petchey F; Allely K; Shiner JI; Bailey G
Endereço:Anthropology, School of Social Sciences, the University of Auckland, Auckland, New Zealand.
Título:Temporal variability in shell mound formation at Albatross Bay, northern Australia.
Fonte:PLoS One; 12(8):e0183863, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:We report the results of 212 radiocarbon determinations from the archaeological excavation of 70 shell mound deposits in the Wathayn region of Albatross Bay, Australia. This is an intensive study of a closely co-located group of mounds within a geographically restricted area in a wider region where many more shell mounds have been reported. Valves from the bivalve Tegillarca granosa (Linnaeus, 1758) were dated. The dates obtained are used to calculate rates of accumulation for the shell mound deposits. These demonstrate highly variable rates of accumulation both within and between mounds. We assess these results in relation to likely mechanisms of shell deposition and show that rates of deposition are affected by time-dependent processes both during the accumulation of shell deposits and during their subsequent deformation. This complicates the interpretation of the rates at which shell mound deposits appear to have accumulated. At Wathayn, there is little temporal or spatial consistency in the rates at which mounds accumulated. Comparisons between the Wathayn results and those obtained from shell deposits elsewhere, both in the wider Albatross Bay region and worldwide, suggest the need for caution when deriving behavioural inferences from shell mound deposition rates, and the need for more comprehensive sampling of individual mounds and groups of mounds.
Tipo de publicação: HISTORICAL ARTICLE; JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes)


  9 / 31214 MEDLINE  
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PMID:28854194
Autor:Stinnesbeck W; Becker J; Hering F; Frey E; González AG; Fohlmeister J; Stinnesbeck S; Frank N; Terrazas Mata A; Benavente ME; Avilés Olguín J; Aceves Núñez E; Zell P; Deininger M
Endereço:Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 234, Heidelberg, Germany.
Título:The earliest settlers of Mesoamerica date back to the late Pleistocene.
Fonte:PLoS One; 12(8):e0183345, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Preceramic human skeletal remains preserved in submerged caves near Tulum in the Mexican state of Quintana Roo, Mexico, reveal conflicting results regarding 14C dating. Here we use U-series techniques for dating a stalagmite overgrowing the pelvis of a human skeleton discovered in the submerged Chan Hol cave. The oldest closed system U/Th age comes from around 21 mm above the pelvis defining the terminus ante quem for the pelvis to 11311±370 y BP. However, the skeleton might be considerable older, probably as old as 13 ky BP as indicated by the speleothem stable isotope data. The Chan Hol individual confirms a late Pleistocene settling of Mesoamerica and represents one of the oldest human osteological remains in America.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes); 4OC371KSTK (Uranium); 60YU5MIG9W (Thorium)


  10 / 31214 MEDLINE  
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PMID:28837661
Autor:Hippmann AA; Schuback N; Moon KM; McCrow JP; Allen AE; Foster LJ; Green BR; Maldonado MT
Endereço:Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
Título:Contrasting effects of copper limitation on the photosynthetic apparatus in two strains of the open ocean diatom Thalassiosira oceanica.
Fonte:PLoS One; 12(8):e0181753, 2017.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:There is an intricate interaction between iron (Fe) and copper (Cu) physiology in diatoms. However, strategies to cope with low Cu are largely unknown. This study unveils the comprehensive restructuring of the photosynthetic apparatus in the diatom Thalassiosira oceanica (CCMP1003) in response to low Cu, at the physiological and proteomic level. The restructuring results in a shift from light harvesting for photochemistry-and ultimately for carbon fixation-to photoprotection, reducing carbon fixation and oxygen evolution. The observed decreases in the physiological parameters Fv/Fm, carbon fixation, and oxygen evolution, concomitant with increases in the antennae absorption cross section (σPSII), non-photochemical quenching (NPQ) and the conversion factor (φe:C/ηPSII) are in agreement with well documented cellular responses to low Fe. However, the underlying proteomic changes due to low Cu are very different from those elicited by low Fe. Low Cu induces a significant four-fold reduction in the Cu-containing photosynthetic electron carrier plastocyanin. The decrease in plastocyanin causes a bottleneck within the photosynthetic electron transport chain (ETC), ultimately leading to substantial stoichiometric changes. Namely, 2-fold reduction in both cytochrome b6f complex (cytb6f) and photosystem II (PSII), no change in the Fe-rich PSI and a 40- and 2-fold increase in proteins potentially involved in detoxification of reactive oxygen species (ferredoxin and ferredoxin:NADP+ reductase, respectively). Furthermore, we identify 48 light harvesting complex (LHC) proteins in the publicly available genome of T. oceanica and provide proteomic evidence for 33 of these. The change in the LHC composition within the antennae in response to low Cu underlines the shift from photochemistry to photoprotection in T. oceanica (CCMP1003). Interestingly, we also reveal very significant intra-specific strain differences. Another strain of T. oceanica (CCMP 1005) requires significantly higher Cu concentrations to sustain both its maximal and minimal growth rate compared to CCMP 1003. Under low Cu, CCMP 1005 decreases its growth rate, cell size, Chla and total protein per cell. We argue that the reduction in protein per cell is the main strategy to decrease its cellular Cu requirement, as none of the other parameters tested are affected. Differences between the two strains, as well as differences between the well documented responses to low Fe and those presented here in response to low Cu are discussed.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Radioisotopes); 0 (Plant Proteins); 0 (Proteome); 789U1901C5 (Copper)



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