40 research outputs found
Tomato seedling physiological responses under different percentages of blue and red photon flux ratios using LEDs and cool white fluorescent lamps
Lamp spectral customization can be a strategy to achieve desirable plant characteristics when plants are grown under sole-source electric lighting. Vegetable transplants can be efficiently and economically grown under indoor-production systems with electrical lighting; however, species-specific light recipes have to be developed to improve plant growth, development and morphology, as well as to reduce electrical consumption. The objective of this study was to evaluate the growth and morphology of tomato transplants to a broad range of blue to red (B:R) photon flux (PF) ratios under LEDs and cool white fluorescent lamps (CWF). Tomato 'Komeett' and 'Beaufort' seedlings were grown in a climate control growth chamber. Using LEDs, seven light treatments with different blue (B), green (G) and red (R) PF ratios were used: 100R, 10B:90R, 20B:28G:52R, 30B:70R, 50B:50R, 75B:25R and 100B. In addition, a CWF treatment served as the control. Hypocotyl length of 'Komeett' decreased with the increase of percent B PF up to 75% B. Plant leaf area was 64-72% greater under treatments emitting both B and R PF than in the 100 B and 100 R treatments. Similarly, tomato 'Komeett' fresh mass, dry mass, leaf number and chlorophyll concentration was comparable among the treatments containing B and R PF and greater than in 100 B and 100 R treatments. However, plant compactness in the 30B:70R treatment was 42% greater than in the 10B:90R treatment. Anthocyanin concentration increased with the increase of percent B PF up to 75% B. Also, plants in 30B:70R and 50B:50R had 39% and 36% greater dry mass than in CWF, respectively. In addition, 30B:70R and 50B:50R LEDs had 172% greater growing efficacy (g kWh(-1)) than high output fluorescent lamps. The addition of G light did not have any effects on tomato physiological responses. `Beaufort' plant morphology and growth were severely affected by intumescences development and intumescence severity decreased under higher percentages of B PF. In summary, 30B:70R, 50B:50R were the best spectrums to produce tomato seedlings under LEDs tested here; however, plant quality under CWF, 10B:90R, 20B:28G:52R, and 75B:25R was also acceptable. Published by Elsevier B.V.USDA NIFA SCRI grant [2010-51181-21369]The authors would like to acknowledge Mark Kroggel and Neal Barto at the University of Arizona (CEAC) for their technical advice. This project was funded by USDA NIFA SCRI grant No: 2010-51181-21369
Conformal Symmetry and the Three Point Function for the Gravitational Axial Anomaly
This work presents a first study of a radiative calculation for the
gravitational axial anomaly in the massless Abelian Higgs model. The two loop
contribution to the anomalous correlation function of one axial current and two
energy-momentum tensors, , is computed
at an order that involves only internal matter fields. Conformal properties of
massless field theories are used in order to perform the Feynman diagram
calculations in the coordinate space representation. The two loop contribution
is found not to vanish, due to the presence of two independent tensor
structures in the anomalous correlator.Comment: 34 pages, 5 figures, RevTex, Minor changes, Final version for Phys.
Rev.
Fish oil consumption prevents glucose intolerance and hypercorticosteronemy in footshock-stressed rats
<p>Abstract</p> <p>Background</p> <p>Environmental stress plays an important role in the development of glucose intolerance influencing lipid and glucose metabolism through sympathetic nervous system, cytokines and hormones such as glucocorticoids, catecholamines and glucagon. Otherwise, fish oil prevents glucose intolerance and insulin resistance. Although the mechanisms involved are not fully understood, it is known that sympathetic and HPA responses are blunted and catecholamines and glucocorticoids concentrations can be modulated by fish consumption. The aim of the present study was to evaluate whether fish oil, on a normal lipidic diet: 1) could prevent the effect of footshock-stress on the development of glucose intolerance; 2) modified adiponectin receptor and serum concentration; and 3) also modified TNF-α, IL-6 and interleukin-10 (IL-10) levels in adipose tissue and liver. The study was performed in thirty day-old male Wistar randomly assigned into four groups: no stressed (C) and stressed (CS) rats fed with control diet, and no stressed (F) and stressed (FS) rats fed with a fish oil rich diet. The stress was performed as a three daily footshock stress sessions.</p> <p>Results</p> <p>Body weight, carcass fat and protein content were not different among groups. FS presented a reduction on the relative weight of RET. Basal serum glucose levels were higher in CS and FS but 15 min after glucose load just CS remained with higher levels than other groups. Serum corticosterone concentration was increased in CS, this effect was inhibited in FS. However, 15 min after footshock-stress, corticosterone levels were similar among groups. IL-6 was increased in EPI of CS but fish oil consumption prevented IL-6 increase in FS. Similar levels of TNF-α and IL-10 in RET, EPI, and liver were observed among groups. Adipo R1 protein concentration was not different among groups. Footshock-stress did not modify AdipoR2 concentration, but fish oil diet increases AdipoR2 protein concentration.</p> <p>Conclusions</p> <p>Footshock-stress promotes glucose intolerance associated to corticosterone serum level and epididymal white adipose tissue IL-6 concentration increase. The fish oil consumption by stressed rats normalized the stress responses. These results suggested that fish oil intake could be useful to minimize or prevent the development of diseases associated to the stress.</p
Stable Isotope Tracking of Endangered Sea Turtles: Validation with Satellite Telemetry and δ15N Analysis of Amino Acids
Effective conservation strategies for highly migratory species must incorporate information about long-distance movements and locations of high-use foraging areas. However, the inherent challenges of directly monitoring these factors call for creative research approaches and innovative application of existing tools. Highly migratory marine species, such as marine turtles, regularly travel hundreds or thousands of kilometers between breeding and feeding areas, but identification of migratory routes and habitat use patterns remains elusive. Here we use satellite telemetry in combination with compound-specific isotope analysis of amino acids to confirm that insights from bulk tissue stable isotope analysis can reveal divergent migratory strategies and within-population segregation of foraging groups of critically endangered leatherback sea turtles (Dermochelys coriacea) across the Pacific Ocean. Among the 78 turtles studied, we found a distinct dichotomy in δ15N values of bulk skin, with distinct “low δ15N” and “high δ15N” groups. δ15N analysis of amino acids confirmed that this disparity resulted from isotopic differences at the base of the food chain and not from differences in trophic position between the two groups. Satellite tracking of 13 individuals indicated that their bulk skin δ15N value was linked to the particular foraging region of each turtle. These findings confirm that prevailing marine isoscapes of foraging areas can be reflected in the isotopic compositions of marine turtle body tissues sampled at nesting beaches. We use a Bayesian mixture model to show that between 82 and 100% of the 78 skin-sampled turtles could be assigned with confidence to either the eastern Pacific or western Pacific, with 33 to 66% of all turtles foraging in the eastern Pacific. Our forensic approach validates the use of stable isotopes to depict leatherback turtle movements over broad spatial ranges and is timely for establishing wise conservation efforts in light of this species’ imminent risk of extinction in the Pacific
Efeitos do exercício crônico sobre a concentração circulante da leptina e grelina em ratos com obesidade induzida por dieta
Type 2 diabetes – an autoinflammatory disease driven by metabolic stress
Type 2 diabetes has traditionally been viewed as a metabolic disorder characterised by chronic high glucose levels, insulin resistance, and declining insulin secretion from the pancreas. Modern lifestyle, with abundant nutrient supply and reduced physical activity, has resulted in dramatic increases in the rates of obesity-associated disease conditions, including diabetes. The associated excess of nutrients induces a state of systemic low-grade chronic inflammation that results from production and secretion of inflammatory mediators from the expanded pool of activated adipocytes. Here, we review the mechanisms by which obesity induces adipose tissue dysregulation, detailing the roles of adipose tissue secreted factors and their action upon other cells and tissues central to glucose homeostasis and type 2 diabetes. Furthermore, given the emerging importance of adipokines, cytokines and chemokines in disease progression, we suggest that type 2 diabetes should now be viewed as an autoinflammatory disease, albeit one that is driven by metabolic dysregulation
Search for gravitational-lensing signatures in the full third observing run of the LIGO-Virgo network
Gravitational lensing by massive objects along the line of sight to the source causes distortions of gravitational wave-signals; such distortions may reveal information about fundamental physics, cosmology and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO--Virgo network. We search for repeated signals from strong lensing by 1) performing targeted searches for subthreshold signals, 2) calculating the degree of overlap amongst the intrinsic parameters and sky location of pairs of signals, 3) comparing the similarities of the spectrograms amongst pairs of signals, and 4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by 1) frequency-independent phase shifts in strongly lensed images, and 2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the non-detection of gravitational-wave lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects
Consumption of fish oil prevents glucose intolerance in rats submitted to footshock stress
BV UNIFESP: Teses e dissertaçõe