145 research outputs found

    An atlas of ECMWF analyses (1980-1987). Part 1: First moment quantities

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    This document is an atlas of the European Center for Medium Range Weather Forecasts (ECMWF) initialized analyses for 1980 to 1987. Various first moment quantities are presented for monthly, seasonal, and annual averages on a global cylindrical projection, as well as, cross section maps of zonal averages. Global maps of winds, temperature, stream function, and velocity potential are presented at 850 and 200 mb. In addition, global maps of the 300 mb height field (total and eddy), the 500 mb vertical velocity, the 850 mb moisture field, and sea level pressure are presented. The average seasonal cycle and anomalies during the 8 year period are presented for selected quantities

    An atlas of ECMWF analyses (1980-1987). Part 2: Second moment quantities

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    This document is an atlas based on European Center for Medium Range Weather Forecasts (ECMWF) initialized analyses for 1980-1987. Transports and variance are presented globally at 200 and 850 mb as well as zonally averaged for seasonal and annual averages. Selected fields are filtered to isolate the synoptic (2.5 days is less than periods is less than 6 days) and low frequency (10 days is less than periods is less than 90 days) regions of the spectrum. In addition, time series of the zonally and monthly averaged transports and variances are presented over the entire 8 year period

    Bone marrow fat is increased in chronic kidney disease by magnetic resonance spectroscopy

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    In aging, the bone marrow fills with fat and this may lead to higher fracture risk. We show that a bone marrow fat measurement by magnetic resonance spectroscopy (MRS), a newer technique not previously studied in chronic kidney disease (CKD), is useful and reproducible. CKD patients have significantly higher bone marrow fat than healthy adults. INTRODUCTION: Renal osteodystrophy leads to increased morbidity and mortality in patients with CKD. Traditional bone biopsy histomorphometry is used to study abnormalities in CKD, but the bone marrow, the source of osteoblasts, has not been well characterized in patients with CKD. METHODS: To determine the repeatability of bone marrow fat fraction assessment by MRS and water-fat imaging (WFI) at four sites in patients with CKD, testing was performed to determine the coefficients of reproducibility and intraclass coefficients (ICCs). We further determined if this noninvasive technique could be used to determine if there are differences in the percent bone marrow fat in patients with CKD compared to matched controls using paired t tests. RESULTS: The mean age of subjects with CKD was 59.8 ± 7.2 years, and the mean eGFR was 24 ± 8 ml/min. MRS showed good reproducibility at all sites in subjects with CKD and controls, with a coefficient of reproducibilities ranging from 2.4 to 13 %. MRS and WFI assessment of bone marrow fat showed moderate to strong agreement (ICC 0.6-0.7) at the lumbar spine, with poorer agreement at the iliac crest and no agreement at the tibia. The mean percent bone marrow fat at L2-L4 was 13.8 % (95 % CI 8.3-19.7) higher in CKD versus controls (p < 0.05). CONCLUSIONS: MRS is a useful and reproducible technique to study bone marrow fat in CKD. Patients with CKD have significantly higher bone marrow fat than healthy adults; the relationship with bone changes requires further analyses

    Cell size as driver and sentinel of phytoplankton community structure and functioning

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    Body size is a decisive functional trait in many organisms, especially for phytoplankton, which span several orders of magnitude in cell volume. Therefore, the analysis of size as a functional trait driving species’ performance has received wide attention in aquatic ecology, amended in recent decades by studies documenting changes in phytoplankton size in response to abiotic or biotic factors in the environment. We performed a systematic literature review to provide an overarching, partially quantitative synthesis of cell size as a driver and sentinel of phytoplankton ecology. We found consistent and significant allometric relationships between cell sizes and the functional performance of phytoplankton species (cellular rates of carbon fixation, respiration and exudation as well as resource affinities, uptake and content). Size scaling became weaker, absent or even negative when addressing C- or volume-specific rates or growth. C-specific photosynthesis and population growth rate peaked at intermediate cell sizes around 100 µm3. Additionally, we found a rich literature on sizes changing in response to warming, nutrients and pollutants. Whereas small cells tended to dominate under oligotrophic and warm conditions, there are a few notable exceptions, which indicates that other environmental or biotic constraints alter this general trend. Grazing seems a likely explanation, which we reviewed to understand both how size affects edibility and how size structure changes in response to grazing. Cell size also predisposes the strength and outcome of competitive interactions between algal species. Finally, we address size in a community context, where size-abundance scaling describes community composition and thereby the biodiversity in phytoplankton assemblages. We conclude that (a) size is a highly predictive trait for phytoplankton metabolism at the cellular scale, with less strong and nonlinear implications for growth and specific metabolism and (b) size structure is a highly suitable sentinel of phytoplankton responses to changing environments. A free Plain Language Summary can be found within the Supporting Information of this article

    Mapping the unique and shared functions of oncogenic KRAS and RIT1 with proteome and transcriptome profiling

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    Aberrant activation of RAS oncogenes is prevalent in lung adenocarcinoma, with somatic mutation of KRAS occurring in ∼30% of tumors. Recently, we identified somatic mutation of the RAS-family GTPase RIT1 in lung adenocarcinoma, but relatively little is known about the biological pathways regulated by RIT1 and how these relate to the oncogenic KRAS network. Here we present quantitative proteomic and transcriptomic profiles from KRAS-mutant and RIT1-mutant isogenic lung epithelial cells and globally characterize the signaling networks regulated by each oncogene. We find that both mutant KRAS and mutant RIT1 promote S6 kinase, AKT, and RAF/MEK signaling, and promote epithelial-to-mesenchymal transition and immune evasion via HLA protein loss. However, KRAS and RIT1 diverge in regulation of phosphorylation sites on EGFR, USO1, and AHNAK proteins. The majority of the proteome changes are related to altered transcriptional regulation, but a small subset of proteins are differentially regulated by both oncoproteins at the post-transcriptional level, including intermediate filament proteins, metallothioneins, and MHC Class I proteins. These data provide the first global, unbiased characterization of oncogenic RIT1 network and identify the shared and divergent functions of oncogenic RIT1 and KRAS GTPases in lung cancer

    PRODUCTION OF BIODIESEL FROM NON EDIBLE CEIBA PENTANDRA SEED OIL HAVING HIGH FFA CONTENT

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    ABSTRACT Recently, most of the biodiesel is produced from edible oils using methanol and an alkaline catalyst. However, large amount of non edible oils are available in India. Often the non edible oil contain high amounts of free fatty acids(FFA), which quickly react with the alkaline catalyst to produce soap then slow down the separation of the ester and glycerin. In the present study, high free fatty acid (14.71%) Ceiba pentandra seed oil was used as a source for biodiesel production. A two-step transesterification process is developed to convert the high FFA oils to its mono-esters. The first step reduces the acid value of the oil to less than 2mg KOH/g of oil using the acid catalyst (H2SO4) and methanol. The second step, alkaline catalyzed transesterification process converts the products of the first step to its mono-esters and glycerol. The reaction parameters such as molar ratio, catalyst concentration, reaction temperature and reaction time were optimized for production of Ceiba pentandra oil methyl ester are analyzed. The two-step esterification procedure converts of crude Ceiba pentandra oil to its methyl esters. The yield of methyl esters from Ceiba pentandra oil under the optimal condition was 92-93%. The viscosity of biodiesel oil is nearer to that of diesel and the calorific value is less than that of diesel because of their oxygen content. The important properties of biodiesel such as density, flash point, fire point and cetane number are found out and compared with that of diesel. This study supports the biodiesel production from nonedible Ceiba pentandra seed oil as a viable alternative to the diesel fuel

    Efficacy of Bacillus thuringiensis var. Kurstaki in the control of two mosquito species (Anopheles stephensi and Culex quinquefasciatus)

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    Abstract: Bioinsecticide Bacillus thuringiensis var. kurstaki (Btk) was used for controlling the mosquito species (Anopheles stephensi and Culex quinquefasciatus) which gave a significant (p&lt;0.05) mortality in both species. The higher concentration of Btk was highly effective compared to the control ones. The controlling effect was dose and time dependent. Among the studied mosquitoes the C. quinquefasciatus (LC 50 0.154%) was more susceptible than A. stephensi (LC 50 0.372%) towards the bioinsecticide Btk

    Intercomparison of the northern hemisphere winter mid-latitude atmospheric variability of the IPCC models

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    We compare, for the overlapping time frame 1962-2000, the estimate of the northern hemisphere (NH) mid-latitude winter atmospheric variability within the XX century simulations of 17 global climate models (GCMs) included in the IPCC-4AR with the NCEP and ECMWF reanalyses. We compute the Hayashi spectra of the 500hPa geopotential height fields and introduce an integral measure of the variability observed in the NH on different spectral sub-domains. Only two high-resolution GCMs have a good agreement with reanalyses. Large biases, in most cases larger than 20%, are found between the wave climatologies of most GCMs and the reanalyses, with a relative span of around 50%. The travelling baroclinic waves are usually overestimated, while the planetary waves are usually underestimated, in agreement with previous studies performed on global weather forecasting models. When comparing the results of various versions of similar GCMs, it is clear that in some cases the vertical resolution of the atmosphere and, somewhat unexpectedly, of the adopted ocean model seem to be critical in determining the agreement with the reanalyses. The GCMs ensemble is biased with respect to the reanalyses but is comparable to the best 5 GCMs. This study suggests serious caveats with respect to the ability of most of the presently available GCMs in representing the statistics of the global scale atmospheric dynamics of the present climate and, a fortiori, in the perspective of modelling climate change.Comment: 39 pages, 8 figures, 2 table
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