144 research outputs found
Accuracy of energy prediction methodologies
In the current market, the specific annual
energy yield (kWh/kWp) of a PV system is gaining in
importance due to its direct link to the financial returns
for possible investors who typically demand an
accuracy of 5% in this prediction. This paper focuses
on the energy prediction of photovoltaic modules
themselves, as there have been significant advances
achieved with module technologies which affect the
device physics in a way that might force the revisiting
of device modelling.
The paper reports the results of a round robin
based evaluation of European modelling
methodologies. The results indicate that the error in
predicting energy yield for the same module at
different locations was within 5% for most of the
methodologies. However, this error increased
significantly if the nominal nameplate rating is used in
the characterization stage. For similar modules at the
same location the uncertainties were much larger due
to module-module variations
Total hemoglobin mass, aerobic capacity, and hbb gene in polish road cyclists
The relationship between genes, amount of hemoglobin, and physical performance are still not clearly defined. The aim of this study was to examine the association between-551C/T and intron 2, +16 C/G polymorphisms in the beta hemoglobin (HBB) gene and total hemoglobin mass (tHbmass) and aerobic capacity in endurance athletes. Total hemoglobin mass and aerobic capacity indices, i. e.,VO2max, oxygen uptake at anaerobic threshold (VO2AT), maximal power output (Pmax), and power at anaerobic threshold (PAT) were determined in 89 young road cyclists, female (n = 39) and male (n = 50), who were genotyped for 2 polymorphisms in the HBB gene. The relative values of aerobic capacity indices differed significantly among intron 2, +16 C/G polymorphisms of the HBB gene only in female cyclists; athletes with GG genotype had significantly higher values of V O2max (p = 0.003), VO2AT (p = 0.007), PAT (p = 0.015), and Pmax (p = 0.004) than C carriers. No relationships were found between the C-carrier model (CC + CG vs. GG in the case of intron 2, +16 C/G and CC + CT vs. TT for -551 C/T polymorphisms of the HBB gene) and relative values of tHbmass. Our results demonstrated that the HBB gene could be related to aerobic capacity, but it seems that it does not result from an increase in the amount of hemoglobin in the blood
Exploring the mycobacteriophage metaproteome: Phage genomics as an educational platform
Bacteriophages are the most abundant forms of life in the biosphere and carry genomes characterized by high genetic diversity and mosaic architectures. The complete sequences of 30 mycobacteriophage genomes show them collectively to encode 101 tRNAs, three tmRNAs, and 3,357 proteins belonging to 1,536 "phamilies" of related sequences, and a statistical analysis predicts that these represent approximately 50% of the total number of phamilies in the mycobacteriophage population. These phamilies contain 2.19 proteins on average; more than half (774) of them contain just a single protein sequence. Only six phamilies have representatives in more than half of the 30 genomes, and only three - encoding tape-measure proteins, lysins, and minor tail proteins - are present in all 30 phages, although these phamilies are themselves highly modular, such that no single amino acid sequence element is present in all 30 mycobacteriophage genomes. Of the 1,536 phamilies, only 230 (15%) have amino acid sequence similarity to previously reported proteins, reflecting the enormous genetic diversity of the entire phage population. The abundance and diversity of phages, the simplicity of phage isolation, and the relatively small size of phage genomes support bacteriophage isolation and comparative genomic analysis as a highly suitable platform for discovery-based education. © 2006 Hatfull et al
Photovoltaic performance measurements in Europe: PV-catapult round robin tests
Two sets of modules have been sent around to different
testing installations across Europe, one set to
laboratories performing indoor calibrations and one set
to laboratories performing outdoor power and energy
ratings. The results show that for crystalline and polycrystalline
devices, a very good agreement between
laboratories has been achieved. A lower agreement between
laboratories has been achieved for thin film devices
and further need for research is identified
Greenland and Canadian Arctic ice temperature profiles database
Here, we present a compilation of 95 ice temperature profiles from 85 boreholes from the Greenland ice sheet and peripheral ice caps, as well as local ice caps in the Canadian Arctic. Profiles from only 31 boreholes (36 %) were previously available in open-access data repositories. The remaining 54 borehole profiles (64 %) are being made digitally available here for the first time. These newly available profiles, which are associated with pre-2010 boreholes, have been submitted by community members or digitized from published graphics and/or data tables. All 95 profiles are now made available in both absolute (meters) and normalized (0 to 1 ice thickness) depth scales and are accompanied by extensive metadata. These metadata include a transparent description of data provenance. The ice temperature profiles span 70 years, with the earliest profile being from 1950 at Camp VI, West Greenland. To highlight the value of this database in evaluating ice flow simulations, we compare the ice temperature profiles from the Greenland ice sheet with an ice flow simulation by the Parallel Ice Sheet Model (PISM). We find a cold bias in modeled near-surface ice temperatures within the ablation area, a warm bias in modeled basal ice temperatures at inland cold-bedded sites, and an apparent underestimation of deformational heating in high-strain settings. These biases provide process level insight on simulated ice temperatures
Nonheritable Cellular Variability Accelerates the Evolutionary Processes of Cancer
Heritable genetic or epigenetic changes in cells are thought to drive tumor development, metastasis, and drug resistance. This essay discusses the possibility that nonheritable phenotypic variability contributes to the evolution of cancer, suggesting new approaches to treatment
Accuracy of Energy Prediction Methodologies
In the current market, the specific annual
energy yield (kWh/kWp) of a PV system is gaining in
importance due to its direct link to the financial returns
for possible investors who typically demand an
accuracy of 5% in this prediction. This paper focuses
on the energy prediction of photovoltaic modules
themselves, as there have been significant advances
achieved with module technologies which affect the
device physics in a way that might force the revisiting
of device modelling.
The paper reports the results of a round robin
based evaluation of European modelling
methodologies. The results indicate that the error in
predicting energy yield for the same module at
different locations was within 5% for most of the
methodologies. However, this error increased
significantly if the nominal nameplate rating is used in
the characterization stage. For similar modules at the
same location the uncertainties were much larger due
to module-module variations
Use of green solvents as pre-treatment of dissolving pulp to decrease CS2 consumption from viscose production
Choline chloride-based deep eutectic solvents are widely used in biomass processing. In this work, four different green solvent mixtures were used as pre-treatment of acid sulphite dissolving pulp with the hypothesis of increasing the possibilities to produce viscose fibres and decreasing the use of the harmful and toxic carbon disulphide in the process. The experiments were performed at two different pulp to solvent mass ratios. Pulp quality parameters were also measured to determine the suitability of the pretreatment: a-cellulose, viscosity, lignin and pentosan content. In addition, X-ray diffraction analysis of pulps at the best solid to liquid ratio was performed to obtain the influence of the crystallinity index. Best results were obtained with the use of lactic acid, with reactivity values close to 94%, giving a reduction of CS2 usage of 15.83%. Furthermore, a linear relationship between the crystallinity index calculated by the XRD and reactivity with a regression factor of 0.87 was found
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