193 research outputs found
Avaliação do comportamento de sementes de algodoeiro (Gossypium hirsutum L.) durante o armazenamento.
Foi avaliado o comportamento das sementes, através de testes de germinação e de vigor
Influência do tamanho sobre a conservação, germinação e vigor de sementes de soja (Glycine max (L.) Merr.).
O presente trabalho foi desenvolvido no Laboratório de Sementes do Departamento de Agricultura e horticultura da ESALQ, constando de destes de germinacao e de vigor realizados em seis épocas bimestrais, com sementes de três cultivares de soja de três tamanhos, conservadas em câmara seca e em ambiente não controlado
On the Impact of Tsallis Statistics on Cosmic Ray Showers
We investigate the impact of the Tsallis nonextensive statistics introduced by intrinsic temperature fluctuations in p-Air ultrahigh energy interactions on observables of cosmic ray showers, such as the slant depth of the maximum Xmax and the muon number on the ground Nμ. The results show that these observables are significantly affected by temperature fluctuations and agree qualitatively with the predictions of Heitler model
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The Double Chooz antineutrino detectors
This article describes the setup and performance of the near and far detectors in the Double Chooz experiment. The electron antineutrinos of the Chooz nuclear power plant were measured in two identically designed detectors with different average baselines of about 400 m and 1050 m from the two reactor cores. Over many years of data taking the neutrino signals were extracted from interactions in the detectors with the goal of measuring a fundamental parameter in the context of neutrino oscillation, the mixing angle θ13. The central part of the Double Chooz detectors was a main detector comprising four cylindrical volumes filled with organic liquids. From the inside towards the outside there were volumes containing gadolinium-loaded scintillator, gadolinium-free scintillator, a buffer oil and, optically separated, another liquid scintillator acting as veto system. Above this main detector an additional outer veto system using plastic scintillator strips was installed. The technologies developed in Double Chooz were inspiration for several other antineutrino detectors in the field. The detector design allowed implementation of efficient background rejection techniques including use of pulse shape information provided by the data acquisition system. The Double Chooz detectors featured remarkable stability, in particular for the detected photons, as well as high radiopurity of the detector components
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Yields and production rates of cosmogenic <sup>9</sup>Li and <sup>8</sup>He measured with the Double Chooz near and far detectors
The yields and production rates of the radioisotopes 9Li and 8He created by cosmic muon spallation on 12C, have been measured by the two detectors of the Double Chooz experiment. The identical detectors are located at separate sites and depths, which means that they are subject to different muon spectra. The near (far) detector has an overburden of ∼120 m.w.e. (∼300 m.w.e.) corresponding to a mean muon energy of 32.1 ± 2.0 GeV (63.7 ± 5.5 GeV). Comparing the data to a detailed simulation of the 9Li and 8He decays, the contribution of the 8He radioisotope at both detectors is found to be compatible with zero. The observed 9Li yields in the near and far detectors are 5.51 ± 0.51 and 7.90 ± 0.51, respectively, in units of 10−8μ−1g−1cm2. The shallow overburdens of the near and far detectors give a unique insight when combined with measurements by KamLAND and Borexino to give the first multi-experiment, data driven relationship between the 9Li yield and the mean muon energy according to the power law Y=Y0(〈Eμ〉/1GeV)α¯, giving α¯=0.72±0.06 and Y0 = (0.43 ± 0.11) × 10−8μ−1g−1cm2. This relationship gives future liquid scintillator based experiments the ability to predict their cosmogenic 9Li background rates
Evaluation of inoculum potential of pathogens in seeds: relation to physiological quality and DNA quantification by qPCR
Consumer Complaints and Company Market Value
Consumer complaints affect company market value and common sense suggests that a negative impact is
expected. However, do complaints always negatively impact company market value? We hypothesize in this
study that complaints may have a non-linear effect on market value. Positive (e.g. avoiding high costs to solve
complaints) and negative (e.g. speedy and intense diffusion) tradeoffs may occur given the level of complaints.
To test our non-linear hypothesis, a panel data was collected from cell phone service providers from 2005 to
2013. The results supported our tradeoff rationale. Low levels of complaints allow for companies to increase
market value, while high levels of complaints cause increasing harm to market value. The sample, model and
period considered in this study, indicates a level of 0.49 complaints per thousand consumers as the threshold for
a shift in tradeoffs. The effects on market value become increasingly negative when trying to make reductions to
move below this level, due to negative tradeoffs
MGS Guaiçara and MGS Vereda: Coffea arabica cultivars resistant to the root-knot nematode meloidogyne paranaenses.
MGS Guaiçara e MGS Vereda are resistant to Meloidogyne paranaensis, one of the most aggressive nematode parasites of coffee. MGS Vereda is an early maturation cultivar, whereas MGS Guaiçara has a medium maturation cycle. Both cultivars produce red fruit, have high size, and high yield potential in infested areas
MicroRNA expression as risk biomarker of breast cancer metastasis : a pilot retrospective case-cohort study
Background: MicroRNAs (miRNAs) are small, non-coding RNA molecules involved in post-transcriptional gene regulation and have recently been shown to play a role in cancer metastasis. In solid tumors, especially breast cancer, alterations in miRNA expression contribute to cancer pathogenesis, including metastasis. Considering the emerging role of miRNAs in metastasis, the identification of predictive markers is necessary to further the understanding of stage-specific breast cancer development. This is a retrospective analysis that aimed to identify molecular biomarkers related to distant breast cancer metastasis development.
Methods: A retrospective case cohort study was performed in 64 breast cancer patients treated during the period from 1998-2001. The case group (n = 29) consisted of patients with a poor prognosis who presented with breast cancer recurrence or metastasis during follow up. The control group (n = 35) consisted of patients with a good prognosis who did not develop breast cancer recurrence or metastasis. These patient groups were stratified according to TNM clinical stage (CS) I, II and III, and the main clinical features of the patients were homogeneous. MicroRNA profiling was performed and biomarkers related to metastatic were identified independent of clinical stage. Finally, a hazard risk analysis of these biomarkers was performed to evaluate their relation to metastatic potential.
Results: MiRNA expression profiling identified several miRNAs that were both specific and shared across all clinical stages (p <= 0.05). Among these, we identified miRNAs previously associated with cell motility (let-7 family) and distant metastasis (hsa-miR-21). In addition, hsa-miR-494 and hsa-miR-21 were deregulated in metastatic cases of CSI and CSII. Furthermore, metastatic miRNAs shared across all clinical stages did not present high sensitivity and specificity when compared to specific-CS miRNAs. Between them, hsa-miR-183 was the most significative of CSII, which miRNAs combination for CSII (hsa-miR-494, hsa-miR-183 and hsa-miR-21) was significant and were a more effective risk marker compared to the single miRNAs.
Conclusions: Women with metastatic breast cancer, especially CSII, presented up-regulated levels of miR-183, miR-494 and miR-21, which were associated with a poor prognosis. These miRNAs therefore represent new risk biomarkers of breast cancer metastasis and may be useful for future targeted therapies.We thank the Researcher Support Center of Barretos Cancer Hospital, especially the statistician Zanardo C. for assisting in the statistical analysis.This study received financial support from Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (Fapesp, Proc: 10/ 16796-0, Sao Paulo, Brazil)
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