8,317 research outputs found

    Methodology to evaluate dripper sensitivity to clogging due to solid particles: an assessment

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    Emitter clogging is a major problem in microirrigation systems, which may result from the isolated or combined efects of physical, chemical, and biological agents. Clogging caused by suspended solid particles is the most common plugging form of emitters. Water quality and emitter geometry are key aspects in clogging processes. Any suitable test procedure to assess the sensitivity of drippers to clogging should take into account the predominant factors that infuence clogging and must reproduce the feld conditions. Tis research set out to assess the performance and suitability of a laboratory clogging test procedure in order to validate a methodology and to provide scientifc results that may support the standardization of a clogging test method. Te evaluated methodology has been used by the IRSTEA laboratory since 1974 (Platform of Research and experiment on Science and Technology for Irrigation - PReSTI, formerly LERMI) and its contents are currently being discussed by the ISO TC23/SC18 committee. Te aim is to defne a standardized testing protocol to evaluate the sensitivity of emitters to clogging due to solid particles. Replications analyzing the clogging resistance of four models of emitting pipes were carried out in a laboratory.Te clogging test procedure enabled an accurate assessment of the combinations of concentration and size of particles that caused clogging in each model of dripper. However, a signifcant variability in degree of clogging was identifed when the results of replications for each model of dripper were compared. Several requirements, concerns, and improvements related to the clogging test protocol were discussed.2018FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2015/19630-

    Changes in cortisol but not in brain-derived neurotrophic factor modulate the association between sleep disturbances and major depression

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    Sleep disturbance is a symptom consistently found in major depression and is associated with a longer course of illness, reduced response to treatment, increased risk of relapse and recurrence. Chronic insomnia has been associated with changes in cortisol and serum brain-derived neurotrophic factor (BDNF) levels, which in turn are also changed in major depression. Here, we evaluated the relationship between sleep quality, salivary cortisol awakening response (CAR), and serum BDNF levels in patients with sleep disturbance and treatment-resistant major depression (n = 18), and in a control group of healthy subjects with good (n = 21) and poor (n = 18) sleep quality. We observed that the patients had the lowest CAR and sleep duration of all three groups and a higher latency to sleep than the healthy volunteers with a good sleep profile. Besides, low CAR was correlated with more severe depressive symptoms and worse sleep quality. There was no difference in serum BDNF levels between groups with distinct sleep quality. Taken together, our results showed a relationship between changes in CAR and in sleep quality in patients with treatment-resistant depression, which were correlated with the severity of disease, suggesting that cortisol could be a physiological link between sleep disturbance and major depression

    Modulation of serum brain-derived neurotrophic factor by a single dose of ayahuasca : observation from a randomized controlled trial

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    Serotonergic psychedelics are emerging as potential antidepressant therapeutic tools, as suggested in a recent randomized controlled trial with ayahuasca for treatment-resistant depression. Preclinical and clinical studies have suggested that serum brain-derived neurotrophic factor (BDNF) levels increase after treatment with serotoninergic antidepressants, but the exact role of BDNF as a biomarker for diagnostic and treatment of major depression is still poorly understood. Here we investigated serum BDNF levels in healthy controls (N = 45) and patients with treatment-resistant depression (N = 28) before (baseline) and 48 h after (D2) a single dose of ayahuasca or placebo. In our sample, baseline serum BDNF levels did not predict major depression and the clinical characteristics of the patients did not predict their BDNF levels. However, at baseline, serum cortisol was a predictor of serum BDNF levels, where lower levels of serum BDNF were detected in a subgroup of subjects with hypocortisolemia. Moreover, at baseline we found a negative correlation between BDNF and serum cortisol in volunteers with eucortisolemia. After treatment (D2) we observed higher BDNF levels in both patients and controls that ingested ayahuasca (N = 35) when compared to placebo (N = 34). Furthermore, at D2 just patients treated with ayahuasca (N = 14), and not with placebo (N = 14), presented a significant negative correlation between serum BDNF levels and depressive symptoms. This is the first double-blind randomized placebo-controlled clinical trial that explored the modulation of BDNF in response to a psychedelic in patients with depression. The results suggest a potential link between the observed antidepressant effects of ayahuasca and changes in serum BDNF, which contributes to the emerging view of using psychedelics as an antidepressant. This trial is registered at http://clinicaltrials.gov (NCT02914769)

    Body composition and resting metabolic rate in obese adolescents

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    Objetivo: Analisar a composição corporal e taxa metabólica de repouso (TMR) de adolescentes com obesidade. Metodologia: Foram avaliados 58 adolescentes, entre 12 e 16 anos (13,7±1,2 anos), com obesidade. A composição corporal foi mensurada por meio da Absortiometria de Raios-x de Dupla Energia (DEXA). A taxa metabólica de repouso e a oxidação de glicose e lipídeos foram determinadas pela medida do oxigênio consumido e pela produção de dióxido de carbono. Foi utilizado teste t de Student para variáveis independentes, análise de regressão linear múltipla e correlação de Pearson, com significância de p<5%. Resultados: Foram observadas diferenças na porcentagem de gordura corporal (p=0,01), porcentagem de massa corporal magra (MCM) (p=0,01), porcentagem de gordura do tronco (p=0,01), massa magra membro inferior (p=0,01) e taxa metabólica de repouso (p=0,04) entre os sexos masculino e feminino. No sexo masculino a MCM foi a melhor preditora de TMR (p=0,01). Houve correlação positiva entre TMR e MCM, assim como observada associação entre a oxidação lipídica e MCM. Conclusão: A composição corporal total e por segmento corporal influenciam a taxa metabólica de repouso e a oxida- ção de substratos. Além disso, a MCM pode ser considerada um fator de aumento do gasto energético de repouso de adolescentes com obesidade.Objective: Analyze body composition and resting metabolic rate (RMR) in obese adolescents. Methods: 58 obese adolescents were assessed between 12 and 16 years (13.7 ± 1.2 years). The body composition was measured dual-energy x-ray absorptiometry (DEXA). The resting metabolic rate and oxidation of glucose and lipids were determined by measuring the oxygen consumption and the production of carbon dioxide. Student t test was used for independent data, multiple linear regression and Pearson correlation, significance was set p <5%. Results: Significant differences were observed in the percentage of body fat (p = 0.01), percentage of lean body mass (LBM) (p = 0.01), percentage body fat (p = 0.01), lower limb lean mass (p = 0.01) and resting metabolic rate (p = 0.04) between males and females. The LBM is highlighted as the best predictor of RMR (p = 0.01). There was a positive correlation between RMR and LBM, as observed association between lipid oxidation and LBM. Conclusion: Total body composition and segment influence the resting metabolic rate and substrate oxidation. In addition, the LBM can be considered a factor of increased resting energy expenditure in obese adolescents

    IKZF1 Deletions with COBL Breakpoints Are Not Driven by RAG-Mediated Recombination Events in Acute Lymphoblastic Leukemia

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    IKZF1 deletion (ΔIKZF1) is an important predictor of relapse in both childhood and adult B-cell precursor acute lymphoblastic leukemia (B-ALL). Previously, we revealed that COBL is a hotspot for breakpoints in leukemia and could promote IKZF1 deletions. Through an international collaboration, we provide a detailed genetic and clinical picture of B-ALL with COBL rearrangements (COBL-r). Patients with B-ALL and IKZF1 deletion (n = 133) were included. IKZF1 ∆1-8 were associated with large alterations within chromosome 7: monosomy 7 (18%), isochromosome 7q (10%), 7p loss (19%), and interstitial deletions (53%). The latter included COBL-r, which were found in 12% of the IKZF1 ∆1-8 cohort. Patients with COBL-r are mostly classified as intermediate cytogenetic risk and frequently harbor ETV6, PAX5, CDKN2A/B deletions. Overall, 56% of breakpoints were located within COBL intron 5. Cryptic recombination signal sequence motifs were broadly distributed within the sequence of COBL, and no enrichment for the breakpoint cluster region was found. In summary, a diverse spectrum of alterations characterizes ΔIKZF1 and they also include deletion breakpoints within COBL. We confirmed that COBL is a hotspot associated with ΔIKZF1, but these rearrangements are not driven by RAG-mediated recombination

    Prime Focus Spectrograph - Subaru's future -

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    The Prime Focus Spectrograph (PFS) of the Subaru Measurement of Images and Redshifts (SuMIRe) project has been endorsed by Japanese community as one of the main future instruments of the Subaru 8.2-meter telescope at Mauna Kea, Hawaii. This optical/near-infrared multi-fiber spectrograph targets cosmology with galaxy surveys, Galactic archaeology, and studies of galaxy/AGN evolution. Taking advantage of Subaru's wide field of view, which is further extended with the recently completed Wide Field Corrector, PFS will enable us to carry out multi-fiber spectroscopy of 2400 targets within 1.3 degree diameter. A microlens is attached at each fiber entrance for F-ratio transformation into a larger one so that difficulties of spectrograph design are eased. Fibers are accurately placed onto target positions by positioners, each of which consists of two stages of piezo-electric rotary motors, through iterations by using back-illuminated fiber position measurements with a wide-field metrology camera. Fibers then carry light to a set of four identical fast-Schmidt spectrographs with three color arms each: the wavelength ranges from 0.38 {\mu}m to 1.3 {\mu}m will be simultaneously observed with an average resolving power of 3000. Before and during the era of extremely large telescopes, PFS will provide the unique capability of obtaining spectra of 2400 cosmological/astrophysical targets simultaneously with an 8-10 meter class telescope. The PFS collaboration, led by IPMU, consists of USP/LNA in Brazil, Caltech/JPL, Princeton, & JHU in USA, LAM in France, ASIAA in Taiwan, and NAOJ/Subaru.Comment: 13 pages, 11 figures, submitted to "Ground-based and Airborne Instrumentation for Astronomy IV, Ian S. McLean, Suzanne K. Ramsay, Hideki Takami, Editors, Proc. SPIE 8446 (2012)
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