Variability in strength of byssus attachment and index condition of subtidal mussels during the maximum growth stage

2021 ◽  
Author(s):  
Xosé A. Padin ◽  
Jose M.F. Babarro ◽  
Elsa Silva ◽  
M. Ángeles Longa Portabales ◽  
Silvia Calvo ◽  
...  
2020 ◽  
pp. 1-8
Author(s):  
Ayse Nur Ulusoy ◽  
O. Adewale Osipitan ◽  
Jon Scott ◽  
Amit J. Jhala ◽  
Nevin C. Lawrence ◽  
...  

Abstract Residual herbicides applied PRE provide early season weed control, potentially avoid the need for multiple POST herbicides, and can provide additional control of herbicide-resistant weeds. Thus, field studies were conducted in 2017 and 2018 at Concord, NE, to evaluate the influence of PRE herbicides on critical time for postemergence weed removal (CTWR) in corn. The studies were arranged in a split-plot design that consisted of three herbicide regimes as main plot treatments and seven weed removal timings as subplot treatments in four replications. The herbicide regimes included no PRE herbicide, atrazine, and a premix of saflufenacil/dimethenamid-P mixed with pyroxasulfone. The weed removal timings were at V3, V6, V9, V12, and V15 corn growth stages and then plots were kept weed-free until harvest. A weed-free and nontreated control were included for comparison. The relationship between corn growth or yield, and weed removal timings in growing degree days (GDD) was described by a four-parameter log-logistic model. This model was used to estimate the critical time for weed removal based on 5% crop yield loss threshold. A delay in weed removal until the V2 to V3 corn growth stage (91 to 126 GDD) reduced corn biomass by 5% without PRE herbicide application. The CTWR started at V3 without PRE herbicide in both years. Atrazine delayed the CTWR up to V5 in both years, whereas saflufenacil/dimethenamid-P plus pyroxasulfone further delayed the CTWR up to the V10 and V8 corn growth stages in 2017 and 2018, respectively. Herbicide applied PRE particularly with multiple sites of action can delay the CTWR in corn up to a maximum growth stage of V10, and delay or reduce the need for POST weed management.


1971 ◽  
Vol 51 (6) ◽  
pp. 499-504 ◽  
Author(s):  
J. E. LANGILLE ◽  
F. W. CALDER

Empire, Leo, Viking and Wallace cultivars of birdsfoot trefoil were evaluated in a greenhouse experiment for total forage production, aerial and root growth, in vitro digestibility, cold hardiness, etiolated regrowth and modulation. Plants were harvested at the vegetative stage (four harvests); 10% bloom (three harvests); 50% bloom (two harvests); and maximum growth (one harvest), at two stubble heights, 2.5 and 7.5 cm. Harvesting at the maximum growth stage produced the most dry matter but the lowest digestibility, with the greatest etiolated regrowth and best nodulation. Production at the vegetative stage produced the least forage which was the most digestible. Empire was the most productive cultivar, with a hardiness rating equal to Leo. At the 10 and 50% bloom stages, Wallace equalled this cultivar in production and there was no difference between the four cultivars in forage production when harvested at the vegetative stage. Viking appeared to be the least hardy of the cultivars examined, although it produced more etiolated regrowth than Empire and Wallace but not as much as Leo. This experiment shows that criteria other than total production must be examined in evaluating birdsfoot trefoil cultivars.


Author(s):  
J. L. Brimhall ◽  
H. E. Kissinger ◽  
B. Mastel

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.


2020 ◽  
Vol 640 ◽  
pp. A53
Author(s):  
L. Löhnert ◽  
S. Krätschmer ◽  
A. G. Peeters

Here, we address the turbulent dynamics of the gravitational instability in accretion disks, retaining both radiative cooling and irradiation. Due to radiative cooling, the disk is unstable for all values of the Toomre parameter, and an accurate estimate of the maximum growth rate is derived analytically. A detailed study of the turbulent spectra shows a rapid decay with an azimuthal wave number stronger than ky−3, whereas the spectrum is more broad in the radial direction and shows a scaling in the range kx−3 to kx−2. The radial component of the radial velocity profile consists of a superposition of shocks of different heights, and is similar to that found in Burgers’ turbulence. Assuming saturation occurs through nonlinear wave steepening leading to shock formation, we developed a mixing-length model in which the typical length scale is related to the average radial distance between shocks. Furthermore, since the numerical simulations show that linear drive is necessary in order to sustain turbulence, we used the growth rate of the most unstable mode to estimate the typical timescale. The mixing-length model that was obtained agrees well with numerical simulations. The model gives an analytic expression for the turbulent viscosity as a function of the Toomre parameter and cooling time. It predicts that relevant values of α = 10−3 can be obtained in disks that have a Toomre parameter as high as Q ≈ 10.


1970 ◽  
Vol 17 ◽  
pp. 17-22 ◽  
Author(s):  
Kamal Singh ◽  
A. A. Khan ◽  
Iram Khan ◽  
Rose Rizvi ◽  
M. Saquib

Plant growth, yield, pigment and protein content of cow-pea were increased significantly at lower levels (20 and 40%) of fly ash but reverse was true at higher levels (80 and 100%). Soil amended by 60% fly ash could cause suppression in growth and yield in respect to 40% fly ash treated cow-pea plants but former was found at par with control (fly ash untreated plants). Maximum growth occurred in plants grown in soil amended with 40% fly ash. Nitrogen content of cow-pea was suppressed progressively in increasing levels of fly ash. Moreover,  Rhizobium leguminosarum  influenced the growth and yield positively but Meloidogyne javanica caused opposite effects particularly at 20 and 40% fly ash levels. The positive effects of R. leguminosarum were marked by M. javanica at initial levels. However, at 80 and 100% fly ash levels, the positive and negative effects of R. leguminosarum and/or M. javanica did not appear as insignificant difference persist among such treatments.Key words:  Meloidogyne javanica; Rhizobium leguminosarum; Fly ash; Growth; YieldDOI: 10.3126/eco.v17i0.4098Ecoprint An International Journal of Ecology Vol. 17, 2010 Page: 17-22 Uploaded date: 28 December, 2010  


2015 ◽  
Vol 41 (1) ◽  
pp. 100 ◽  
Author(s):  
Chao ZHANG ◽  
Dong-Xia ZHAN ◽  
Ya-Li ZHANG ◽  
Hong-Hai LUO ◽  
Ling GOU ◽  
...  

1988 ◽  
Vol 80 (4) ◽  
pp. 586-591 ◽  
Author(s):  
W. B. Hallmark ◽  
C. J. DeMooy ◽  
H. F. Mooris ◽  
John Pesek ◽  
K. P. Shao ◽  
...  

2019 ◽  
Vol 15 (8) ◽  
pp. 883-891
Author(s):  
Syeda Abida Ejaz ◽  
Mariia Miliutina ◽  
Peter Langer ◽  
Aamer Saeed ◽  
Jamshed Iqbal

Background: Previously, we have identified 3,3′–carbonyl–bis(chromones) (1a-h, 5e) and 3–(5–(benzylideneamino)thiozol–3–yl)–2H–chromen–2–ones (7a-j) as potent inhibitors of tissue non-specific alkaline phosphatase (TNAP). The present study was designed to investigate the cytotoxic and pro-apoptotic effect of the said derivatives. Methods: The anti-proliferative effect of the derivatives was investigated in three cancer cell lines i.e., MCF-7, K-562, HeLa and normal BHK21 cells using MTT assay. The pro-apoptotic effect of the most potent derivatives was investigated by using flow cytometry, DAPI and PI staining and DNA binding studies. Results: Among all the screened compounds, 1f, 1d, 1c (from 3,3′–carbonyl–bis(chromones), 7c, 7h and 7i (from 3–(5–(benzylideneamino)thiozol–3–yl)–2H–chromen–2–ones) exhibited remarkable growth inhibitory effects. Compounds 1f and 7c were found to be the most potent cytotoxic derivatives against MCF-7; 1d and 7h inhibited most of the proliferation of K-562 cells, whereas 1c and 7i showed maximum growth inhibition in HeLa cells. The identified compounds exerted lower micromolar potency against the respective cell line with significant selectivity over the normal cells (BHK–21). The identified compounds also induced either G2 or S-phase arrest within the respective cancer cells, chromatin condensation and nuclear fragmentation, as well as maximum interaction with DNA. Conclusions: These results provide evidence that the characteristic chemical features of attached groups are the key factors for their anticancer effects and play a useful role in revealing the mechanisms of action in relation to the known compounds in future research programs.


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