517 research outputs found
Pheromone traps for monitoring Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) in the presence of mating disruption
High-dose pheromone lures have proved useful for monitoring some lepidopteran pests in the presence of mating disruption, but not others. We performed experiments in commercial and pilot scale facilities to examine the effect of pheromone dose on detection of Indianmeal moth, Plodia interpunctella (Lepidoptera: Pyralidae), in the presence of mating disruption. When P. interpunctella males were released into 1000 m3 rooms containing traps baited with 0, 1, or 10 mg (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac), traps containing 10 mg captured more than those baited with 1 mg in both the presence and absence of mating disruption. Traps baited with 1 mg captured fewer males in the presence of mating disruption than in its absence, but the opposite was observed with traps baited with 10 mg. When males released into 73 m3 rooms were exposed sequentially to blank traps, traps baited with unmated females, and traps baited with 0.1 mg and then 1.0 mg Z9, E12-14:Ac in the presence or absence of mating disruption, 92% of trapped males were captured in female-baited traps in the absence of mating disruption, whereas in the presence of mating disruption 72% of males captured were caught in synthetic pheromone traps. These data suggest that pheromone lures can be used for monitoring P. interpunctella in the presence of mating disruption. Implications of these data for mass trapping are also discussed. Keywords: Plodia interpunctella, Mating disruption, Monitoring, Pheromone lures, Mass trappin
Bivariate stochastic modeling of functional response with natural mortality
A correction due to Abbott (1925) is the standard method of dealing with control mortality in insect bioassay to estimate the mortality of an insect conditional on control mortality not having occurred. In this article a bivariate stochastic process for overall mortality is developed in which natural mortality and predation are jointly modeled to take account of the competing-risks associated with prey loss. The total mortality estimate from this model is essentially identical with that from more classical modeling. However, when predation loss is estimated in the absence of control mortality the results are somewhat different, with the estimate from the bivariate model being lower than that from using Abbott’s formula in conjunction with the classical model. It is argued that overdispersion in observed mortality data corresponds to correlated outcomes (death or survival) for the prey initially present, while Abbott’s correction relies implicitly on independence
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Does Glucose Variability Influence the Relationship Between Mean Plasma Glucose and Levels in Type 1 and Type 2 Diabetic Patients?
Objective: The A1C-Derived Average Glucose (ADAG) study demonstrated a linear relationship between and mean plasma glucose (MPG). As glucose variability (GV) may contribute to glycation, we examined the association of several glucose variability indices and the MPG- relationship. Research Design and Methods: Analyses included 268 patients with type 1 diabetes and 159 with type 2 diabetes. MPG during 3 months was calculated from 7-point self-monitored plasma glucose and continuous glucose monitoring. We calculated three different measures of GV and used a multiple-step regression model to determine the contribution of the respective GV measures to the MPG- relationship. Results: GV, as reflected by SD and continuous overlapping net glycemic action, had a significant effect on the MPG- relationship in type 1 diabetic patients so that high GV led to a higher level for the same MPG. In type 1 diabetes, the impact of confounding and effect modification of a low versus high SD at an MPG level of 160 mg/dL on the level is 7.02 vs. 7.43 and 6.96 vs. 7.41. All GV measures showed the same tendency. Conclusions: In only type 1 diabetic patients, GV shows a significant interaction with MPG in the association with . This effect is more pronounced at higher levels. However, the impact of GV on the level in type 1 diabetes is modest, particularly when is close to the treatment target of 7%
The shape and erosion of pebbles
The shapes of flat pebbles may be characterized in terms of the statistical
distribution of curvatures measured along their contours. We illustrate this
new method for clay pebbles eroded in a controlled laboratory apparatus, and
also for naturally-occurring rip-up clasts formed and eroded in the Mont
St.-Michel bay. We find that the curvature distribution allows finer
discrimination than traditional measures of aspect ratios. Furthermore, it
connects to the microscopic action of erosion processes that are typically
faster at protruding regions of high curvature. We discuss in detail how the
curvature may be reliable deduced from digital photographs.Comment: 10 pages, 11 figure
Defective Differentiation of Myeloid and Plasmacytoid Dendritic Cells in Advanced Cancer Patients is not Normalized by Tyrosine Kinase Inhibition of the Vascular Endothelial Growth Factor Receptor
Tumor-derived vascular endothelial growth factor (VEGF) has previously been identified as a causative factor in the disturbed differentiation of myeloid dendritic cells (DC) in advanced cancer patients. Here, we investigated the potential of vascular endothelial growth factor receptor (VEGFR) tyrosine kinase (TK) inhibition to overcome this defective DC differentiation. To this end, peripheral blood DC (PBDC) precursor and subset frequencies were measured in 13 patients with advanced cancer before and after treatment with AZD2171, a TK inhibitor (TKI) of VEGFR, coadministered with gefitinib, and an epidermal growth factor receptor (EGFR) TKI. Of note, not only myeloid DC but also plasmacytoid DC frequencies were significantly reduced in the blood of the cancer patients prior to treatment, as compared to healthy controls. Moreover, besides an accumulated population of immature myeloid cells (ImC), a population of myeloid suppressor cells (MSC) was significantly increased. Upon systemic VEGFR TK inhibition, DC frequencies did not increase, whereas the rate of circulating MSC showed a slight, but not significant, decrease. In conclusion, TK inhibition of VEGFR with AZD2171 does not restore the defective PBDC differentiation observed in advanced cancer patients
Control of primary productivity and the significance of photosynthetic bacteria in a meromictic kettle lake.
During 1986 planktonic primary production and controlling factors were investigated in a small (A0 = 11.8 · 103 m2, Zmax = 11.5 m) meromictic kettle lake (Mittlerer Buchensee). Annual phytoplankton productivity was estimated to ca 120 gC · m–2 · a–1 (1,42 tC · lake–1 · a–1). The marked thermal stratification of the lake led to irregular vertical distributions of chlorophylla concentrations (Chla) and, to a minor extent, of photosynthesis (Az). Between the depths of 0 to 6 m low Chla concentrations (< 7 mg · m–3) and comparatively high background light attenuation (kw = 0,525 m–1, 77% of total attenuation due to gelbstoff and abioseston) was found. As a consequence, light absorption by algae was low (mean value 17,4%) and self-shading was absent.
Because of the small seasonal variation of Chla concentrations, no significant correlation between Chla and areal photosynthesis (A) was observed. Only in early summer (June–July) biomass appears to influence the vertical distribution of photosynthesis on a bigger scale. Around 8 m depth, low-light adapted algae and phototrophic bacteria formed dense layers. Due to low ambient irradiances, the contribution of these organisms to total primary productivity was small. Primary production and incident irradiance were significantly correlated with each other (r2 = 0.68). Although the maximum assimilation number (Popt) showed a clear dependence upon water temperature (Q10 = 2.31), the latter was of minor importance to areal photosynthesis
Emissions of methane in Europe inferred by total column measurements
Using five long-running ground-based atmospheric observatories in Europe, we demonstrate the utility of long-term, stationary, ground-based measurements of atmospheric total columns for verifying annual methane emission inventories. Our results indicate that the methane emissions for the region in Europe between Orléans, Bremen, Białystok, and Garmisch-Partenkirchen are overestimated by the state-of-the-art inventories of the Emissions Database for Global Atmospheric Research (EDGAR) v4.2 FT2010 and the high-resolution emissions database developed by the Netherlands Organisation for Applied Scientific Research (TNO) as part of the Monitoring Atmospheric Composition and Climate project (TNO-MACC_III), possibly due to the disaggregation of emissions onto a spatial grid. Uncertainties in the carbon monoxide inventories used to compute the methane emissions contribute to the discrepancy between our inferred emissions and those from the inventories
Real-life glycaemic profiles in non-diabetic individuals with low fasting glucose and normal HbA1c: the A1C-Derived Average Glucose (ADAG) study
Abstract
AIMS/HYPOTHESIS:
Real-life glycaemic profiles of healthy individuals are poorly studied. Our aim was to analyse to what extent individuals without diabetes exceed OGTT thresholds for impaired glucose tolerance (IGT) and diabetes.
METHODS:
In the A1C-Derived Average Glucose (ADAG) study, 80 participants without diabetes completed an intensive glucose monitoring period of 12 weeks. From these data, we calculated the average 24 h glucose exposure as time spent above different plasma glucose thresholds. We also derived indices of postprandial glucose levels, glucose variability and HbA(1c).
RESULTS:
We found that 93% of participants reached glucose concentrations above the IGT threshold of 7.8 mmol/l and spent a median of 26 min/day above this level during continuous glucose monitoring. Eight individuals (10%) spent more than 2 h in the IGT range. They had higher HbA(1c), fasting plasma glucose (FPG), age and BMI than those who did not. Seven participants (9%) reached glucose concentrations above 11.1 mmol/l during monitoring.
CONCLUSIONS/INTERPRETATION:
Even though the non-diabetic individuals monitored in the ADAG study were selected on the basis of a very low level of baseline FPG, 10% of these spent a considerable amount of time at glucose levels considered to be 'prediabetic' or indicating IGT. This highlights the fact that exposure to moderately elevated glucose levels remains under-appreciated when individuals are classified on the basis of isolated glucose measurements
Curriculum vitae of the LOTOS-EUROS (v2.0) chemistry transport model
The development and application of chemistry transport models has a long
tradition. Within the Netherlands the LOTOS–EUROS model has been developed by
a consortium of institutes, after combining its independently developed
predecessors in 2005. Recently, version 2.0 of the model was released as an
open-source version. This paper presents the curriculum vitae of the model
system, describing the model's history, model philosophy, basic features and a
validation with EMEP stations for the new benchmark year 2012, and presents
cases with the model's most recent and key developments. By setting the model
developments in context and providing an outlook for directions for further
development, the paper goes beyond the common model description. With an
origin in ozone and sulfur modelling for the models LOTOS and EUROS, the
application areas were gradually extended with persistent organic pollutants,
reactive nitrogen, and primary and secondary particulate matter. After the
combination of the models to LOTOS–EUROS in 2005, the model was further
developed to include new source parametrizations (e.g. road resuspension,
desert dust, wildfires), applied for operational smog forecasts in the
Netherlands and Europe, and has been used for emission scenarios, source
apportionment, and long-term hindcast and climate change scenarios.
LOTOS–EUROS has been a front-runner in data assimilation of ground-based and
satellite observations and has participated in many model intercomparison
studies. The model is no longer confined to applications over Europe but is
also applied to other regions of the world, e.g. China. The increasing
interaction with emission experts has also contributed to the improvement of
the model's performance. The philosophy for model development has always been
to use knowledge that is state of the art and proven, to keep a good balance
in the level of detail of process description and accuracy of input and
output, and to keep a good record on the effect of model changes using
benchmarking and validation. The performance of v2.0 with respect to EMEP
observations is good, with spatial correlations around 0.8 or higher for
concentrations and wet deposition. Temporal correlations are around 0.5 or
higher. Recent innovative applications include source apportionment and data
assimilation, particle number modelling, and energy transition scenarios
including corresponding land use changes as well as Saharan dust forecasting.
Future developments would enable more flexibility with respect to model
horizontal and vertical resolution and further detailing of model input data.
This includes the use of different sources of land use characterization
(roughness length and vegetation), detailing of emissions in space and time,
and efficient coupling to meteorology from different meteorological models
Mariprofundus ferrooxydans PV-1 the First Genome of a Marine Fe(II) Oxidizing Zetaproteobacterium
© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS One 6 (2011): e25386, doi:10.1371/journal.pone.0025386.Mariprofundus ferrooxydans PV-1 has provided the first genome of the recently discovered Zetaproteobacteria subdivision. Genome analysis reveals a complete TCA cycle, the ability to fix CO2, carbon-storage proteins and a sugar phosphotransferase system (PTS). The latter could facilitate the transport of carbohydrates across the cell membrane and possibly aid in stalk formation, a matrix composed of exopolymers and/or exopolysaccharides, which is used to store oxidized iron minerals outside the cell. Two-component signal transduction system genes, including histidine kinases, GGDEF domain genes, and response regulators containing CheY-like receivers, are abundant and widely distributed across the genome. Most of these are located in close proximity to genes required for cell division, phosphate uptake and transport, exopolymer and heavy metal secretion, flagellar biosynthesis and pilus assembly suggesting that these functions are highly regulated. Similar to many other motile, microaerophilic bacteria, genes encoding aerotaxis as well as antioxidant functionality (e.g., superoxide dismutases and peroxidases) are predicted to sense and respond to oxygen gradients, as would be required to maintain cellular redox balance in the specialized habitat where M. ferrooxydans resides. Comparative genomics with other Fe(II) oxidizing bacteria residing in freshwater and marine environments revealed similar content, synteny, and amino acid similarity of coding sequences potentially involved in Fe(II) oxidation, signal transduction and response regulation, oxygen sensation and detoxification, and heavy metal resistance. This study has provided novel insights into the molecular nature of Zetaproteobacteria.Funding has been provided by the NSF Microbial Observatories Program (KJE, DE), NSF’s Science and Technology Program, by the Gordon and Betty
Moore Foundation (KJE), the College of Letters, Arts, and Sciences at the University of Southern California (KJE), and by the NASA Astrobiology Institute (KJE, DE).
Advanced Light Source analyses at the Lawrence Berkeley National Lab are supported by the Office of Science, Basic Energy Sciences, Division of Materials Science
of the United States Department of Energy (DE-AC02-05CH11231)
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