Outbursts of Southern Dwarf Novae

1979 ◽  
Vol 46 ◽  
pp. 89-95
Author(s):  
Frank M. Bateson
Keyword(s):  
Orbital Period ◽  
Dwarf Novae ◽  
The Mean ◽  
Rate Of Decline ◽  
Different Levels ◽  
Visual Observations

Abstract.The mean cycles and types of maxima for a number of dwarf novae are tabulated. It is shown that supermaxima are not confined to dwarf novae of short mean cycles. The decline rates for some stars are examined to ascertain if the orbital period, accurate to within ten percent, could be derived from visual observations. It is shown that, at least for some stars, the rate of decline differs widely at different levels of brightness, and, also, between dissimilar maxima of the same star.

scholarly journals Systematics of Dwarf Novae

1987 ◽  
Vol 93 ◽  
pp. 3-13
Author(s):  
B. Warner
Keyword(s):  
Orbital Period ◽  
Strong Correlation ◽  
Absolute Magnitude ◽  
Dwarf Novae ◽  
Maximum Light ◽  
Wide Scatter ◽  
The Mean ◽  
Tight Correlation

AbstractFrom about 30 Dwarf Novae with the best determined distances the following relationships are found.(i)a tight correlation between absolute magnitude at maximum light, Mv (max), and orbital period, P.(ii)a correlation between Mv (min) and P showing wide scatter.(iii)a correlation between Mv (mean), the mean absolute magnitude averaged over normal outbursts, and P, again with wide scatter. The scatter is shown to correlate strongly with outburst timescale Tn.(iv)a strong correlation between range, Mv (min) - Mv (max), and Tn (the Kukarkin-Parenago relationship).(v)a strong correlation between range My. (mean) - Mv (max), and both Tn and P.This final correlation is interpreted in terms of the disc instability model of dwarf novae and successfully predicts the observed width of outburst versus P relationship.

OVARIAN ASCORBIC ACID DEPLETION TEST FOR LUTEINIZING HORMONE

1967 ◽  
Vol 56 (4) ◽  
pp. 619-625 ◽  
Author(s):  
Hans Jacob Koed ◽  
Christian Hamburger
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Dose Response ◽  
Response Curve ◽  
Dose Response Curve ◽  
Human Origin ◽  
Response Curves ◽  
Significant Difference ◽  
The Mean ◽  
Different Levels

ABSTRACT Comparison of the dose-response curves for LH of ovine origin (NIH-LH-S8) and of human origin (IRP-HMG-2) using the OAAD test showed a small, though statistically significant difference, the dose-response curve for LH of human origin being a little flatter. Two standard curves for ovine LH obtained with 14 months' interval, were parallel but at different levels of ovarian ascorbic acid. When the mean ascorbic acid depletions were calculated as percentages of the control levels, the two curves for NIH-LH-S8 were identical. The use of standards of human origin in the OAAD test for LH activity of human preparations is recommended.

Reduced oxygenation but not fibrosis defined by functional magnetic resonance imaging predicts the long-term progression of chronic kidney disease

2018 ◽  
Vol 35 (6) ◽  
pp. 964-970 ◽  
Author(s):  
Kei Sugiyama ◽  
Tsutomu Inoue ◽  
Eito Kozawa ◽  
Masahiro Ishikawa ◽  
Akira Shimada ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Chronic Kidney Disease ◽  
Regression Analysis ◽  
Linear Regression Analysis ◽  
Resonance Imaging ◽  
Bold Mri ◽  
Adc Values ◽  
The Mean ◽  
Rate Of Decline ◽  
Observation Period

Abstract Background Although chronic hypoxia and fibrosis may be a key to the progression of chronic kidney disease (CKD), a noninvasive means of measuring these variables is not yet available. Here, using blood oxygen level–dependent (BOLD) and diffusion-weighted (DW) magnetic resonance imaging (MRI), we assessed changes in renal tissue oxygenation and fibrosis, respectively, and evaluated their correlation with prognosis for renal function. Methods The study was conducted under a single-center, longitudinal, retrospective observational design. We examined the prognostic significance of T2* values of BOLD-MRI and apparent diffusion coefficient (ADC) values on DW-MRI and other clinical parameters. The rate of decline in estimated glomerular filtration rate (eGFR) was calculated by linear regression analysis using changes in eGFR during the observation period. Results A total of 91 patients were enrolled, with a mean age of 55.8 ± 15.6 years. Among patients, 51 (56.0%) were males and 38 (41.8%) had diabetes mellitus. The mean eGFR was 49.2 ± 28.9 mL/min/1.73 m2 and the mean observation period was 5.13 years. ADC values of DW-MRI but not T2* values of BOLD-MRI were well correlated with eGFR at the initial time point. The mean annual rate of decline in eGFR during the 5-year observation period was −1.92 ± 3.00 mL/min/1.73 m2. On multiple linear regression analysis, the rate of decline in eGFR was significantly correlated with eGFR at the start point, period average amount of proteinuria and T2* values, but not with ADC values (t = 2.980, P = 0.004). Conclusions Reduced oxygenation as determined by low T2* values on BOLD-MRI is a clinically useful marker of CKD progression.

scholarly journals Pre-selection of apple seedlings for partial powdery mildew (Podosphaera leucotricha Ell. et Ev. /Salm./) resistance

2011 ◽  
Vol 50 (No. 2) ◽  
pp. 65-69 ◽  
Author(s):  
J. Blažek
Keyword(s):  
Powdery Mildew ◽  
First Year ◽  
Podosphaera Leucotricha ◽  
Green House ◽  
Healthy State ◽  
The Mean ◽  
Resistant Genotypes ◽  
Different Levels ◽  
Final Selection ◽  
Selection Of

Incidences of powdery mildew were repeatedly evaluated for two years on 1 420 young seedlings of 20 progenies (of different levels of mildew susceptibility) in a green house, and then for 10 years on 642 seedlings in an orchard. Part of the seedlings in the orchard were pre-selected for the characteristic and others not. Except for the first scoring done in the first year, there was no correlation between mildew incidence on individual seedlings in the green house and their mean performance in the orchard. The seedlings with scores above 6 (resistant or tolerant) at the first stage of evaluation in the green house, however, yielded four times more desirable seedlings after final selection in the orchard than the mean of the total. The progenies that had a better healthy state as a whole yielded more partially resistant genotypes than those with low mean scores. Therefore, the progenies that most rapidly develop infestation on the whole lot should be discarded, whereas those that retain a healthy state longer should be subjected to individual selection according to the previous item.

scholarly journals Ultraviolet Observations of Cataclysmic Variables

1987 ◽  
Vol 93 ◽  
pp. 205-205 ◽  
Author(s):  
F. Verbunt
Keyword(s):  
Orbital Period ◽  
Cataclysmic Variables ◽  
Type Systems ◽  
Terminal Velocity ◽  
Dwarf Novae ◽  
Preliminary Results ◽  
System Type ◽  
International Ultraviolet Explorer ◽  
Flux Level ◽  
Ultraviolet Observations

AbstractThe preliminary results of the analysis of more than 1000 spectra of cataclysmic variables in the archive of the International Ultraviolet Explorer were presented at the meeting. To characterize the slope of the spectra I use F = log(f1460Å/f2880Å). For most spectra F lies between 0.2 and 0.7. No correlation of F with orbital period, inclination, system type or (for dwarf novae) length of the interoutburst interval are found, apart from somewhat lower values of F for DQ Her type systems. Out of 16 dwarf novae for which spectra both at outburst maximum and minimum are available 11 show no large difference in F between maximum and minimum, and in 5 F declines with the flux level. Out of 6 dwarf novae 5 show very red spectra during the rise to maximum, and 1 shows slopes during rise similar to those during decline.In the ultraviolet resonance lines, due to a wind from the disc, no correlation is found between inclination and terminal velocity.

scholarly journals MEAN SURFACE TEMPERATURE OF JAPANESE QUAIL EXPOSED TO DIFFERENT LEVELS OF AIR VELOCITY AND TEMPERATURE AT START OF LAY

2020 ◽  
Vol 4 (2) ◽  
pp. 15-18
Author(s):  
Tatiany Carvalho dos Santos ◽  
Richard Stephen Gates ◽  
Ilda De Fátima Ferreira Tinôco ◽  
Sérgio Zolnier ◽  
Letícia Cibele da Silva Ramos Freitas
Keyword(s):  
Surface Temperature ◽  
Air Temperature ◽  
Japanese Quail ◽  
Systems Engineering ◽  
Air Velocity ◽  
Agricultural Engineering ◽  
Initial Stage ◽  
Different Temperatures ◽  
The Mean ◽  
Different Levels

The objective of this study was to evaluate the effect of different air velocities and temperature at the feeder on mean surface temperature of Japanese quail during the initial stage of laying. The experiment was carried out at the Center for Research in Environment and Agroindustry Systems Engineering (AMBIAGRO), Department of Agricultural Engineering, Federal University of Viçosa, Viçosa/MG, Brazil. A total of 216 Japanese quail in the initial laying phase were placed in four environmental chambers with different temperatures and air velocity, where they were housed and distributed randomly in 2 galvanized wire cages, with 3 partitions each and 27 birds/cage, and a density of approximately 155.6 cm²/bird. The experimental design consisted of randomized blocks with replications of two treatments (air velocity at the feeder: 0, 1, 2, and 3 m/s and air temperature: 17, 23, 29 and 35°C). The mean surface temperature was analyzed by Two-Way ANOVA, with treatment means separated by the Tukey test (P < 0.05). There was a significant positive correlation between air temperature and mean surface temperature (MST). Air velocity is important in removing heat from the surface of birds.

scholarly journals Yield Loss Associated with Different Levels of Stem Rust Resistance in Bread Wheat

Plant Disease ◽  
2018 ◽  
Vol 102 (12) ◽  
pp. 2531-2538 ◽  
Author(s):  
Tegwe Soko ◽  
Cornelia M. Bender ◽  
Renée Prins ◽  
Zacharias A. Pretorius
Keyword(s):  
Stem Rust ◽  
Yield Loss ◽  
Field Trials ◽  
Susceptible Variety ◽  
Yield Reduction ◽  
Adult Plant ◽  
Different Types ◽  
The Mean ◽  
Disease Pressure ◽  
Different Levels

Puccinia graminis f. sp. tritici race Ug99 (syn. TTKSK) has been identified as a major threat to wheat production based on its broad virulence. Despite its importance, the effect of Ug99 on different types of resistance in wheat has not been thoroughly researched. In field trials conducted with P. graminis f. sp. tritici race PTKST (Ug99 race group) over 2 years, AUDPC differentiated the moderately susceptible variety SC Stallion (515) and susceptible entries SC Nduna (995) and Line 37-07 (1634) from those with adult plant resistance (APR). AUDPC of APR varieties W1406 (256), W6979 (399), and Kingbird (209) was higher than the mean of 25 recorded for the all stage resistant (ASR) variety SC Sky. In fungicide-protected and unprotected plots, race PTKST resulted in a mean yield loss of 21.3%, with susceptible Line 37-03 recording a 47.9% decrease in grain yield. Yield reduction in APR varieties reached 19.5% in W1406, whereas the ASR control SC Sky showed a mean loss of 6.4%. Although APR reduced the effects of stem rust on yield and yield components under conditions of high disease pressure, it did not provide the same protection as effective ASR.

scholarly journals Grammatical Intricacy in EFL Textbooks

2017 ◽  
Vol 5 (2) ◽  
pp. 127 ◽  
Author(s):  
Vinh To
Keyword(s):  
Foreign Language ◽  
Teaching And Learning ◽  
Tertiary Education ◽  
Linguistic Features ◽  
Linguistic Complexity ◽  
Efl Learners ◽  
The Mean ◽  
Lexical Density ◽  
English Textbooks ◽  
Different Levels

Grammatical intricacy is an important concept in charactering complexity of language (Halliday, 2008). However, this concept has not yet been fully investigated in the teaching and learning of English as a foreign language (TEFL), particular in English as a foreign language (EFL) textbooks in higher education. This paper aims to examine grammatical intricacy across textbook levels in a book series used in tertiary education in the Vietnamese context. This is part of a larger research project looking at linguistic complexity of English textbooks in the TEFL setting. The research employed Systemic Functional Linguistics (SFL) as the main theoretical framework and Halliday’s method as a measure of grammatical intricacy to look at how this language feature was used in reading comprehension texts in four textbooks at different levels including elementary, pre-intermediate, inter-mediate and upper-intermediate. The findings revealed that grammatical intricacy increased in accordance with the book levels. Particularly, the mean scores of grammatical intricacy showed a gradual increase from the elementary to the intermediate book level; though they were not different significantly and the upper-intermediate textbook did not show the topmost grammatical complexity. These findings suggest that the use of grammatical intricacy in the investigated textbooks was appropriate for EFL learners across levels; however, the use of other linguistic features such as lexical density and nominalisation may potentially impact the use of simple clauses in the textbooks at a higher level. Thus, further investigations are recommended to fully explore the complexity of textbook language.      

scholarly journals Superoutbursts and Superhumps of SU UMa Stars

1988 ◽  
Vol 108 ◽  
pp. 238-239
Author(s):  
Yoji Osaki ◽  
Masahito Hirose
Keyword(s):  
Accretion Disk ◽  
Orbital Period ◽  
White Dwarf ◽  
Binary Systems ◽  
Roche Lobe ◽  
Light Curves ◽  
Close Binary ◽  
Dwarf Novae ◽  
Dwarf Nova ◽  
Close Binary Systems

SU UMa stars are one of subclasses of dwarf novae. Dwarf novae are semi-detached close binary systems in which a Roche-lobe filling red dwarf secondary loses matter and the white dwarf primary accretes it through the accretion disk. The main characteristics of SU UMa subclass is that they show two kinds of outbursts: normal outbursts and superoutbursts. In addition to the more frequent narrow outbursts of normal dwarf nova, SU UMa stars exhibit “superoutbursts”, in which stars reach about 1 magnitude brighter and stay longer than in normal outburst. Careful photometric studies during superoutburst have almost always revealed the “superhumps”: periodic humps in light curves with a period very close to the orbital period of the system. However, the most curious of all is that this superhump period is not exactly equal to the orbital period, but it is always longer by a few percent than the orbital period.

Force Variability as an Objective Measure of Surgical Skill

2015 ◽  
Vol 74 (6) ◽  
Author(s):  
Siti Nor Zawani Ahmmad ◽  
Chew Zhen San ◽  
Eileen Su Lee Ming ◽  
Yeong Che Fai
Keyword(s):  
Objective Measure ◽  
Assessment Model ◽  
Force Variability ◽  
Surgical Skill ◽  
Control Task ◽  
Force Matching ◽  
Significant Difference ◽  
Target Force ◽  
The Mean ◽  
Different Levels

This study investigated the force variability of subjects with different level of surgical skills for different force levels. Twelve participants were recruited from three different levels of surgical experiences: A group of surgeon (N = 4), medical student (N = 3) and engineering student  (N = 5) underwent a simple finger force control task using a custom developed ‘Force Matching’ module.  Three different levels of target force were used: 2 N, 4 N, and 6 N. The task was performed simultaneously using right and left hands. The mean error of force was measured to compare the performance between the three group using Kruskal-Wallis test. A statistically significant difference was detected among the three groups at 2 N when using right hand. We also found that the surgeon group made less error compared to the two other groups at force level 4 N and 6 N for both hands. This finding has important implication for developing a parametric assessment model to evaluate basic skill level in surgical procedures. However, for most accurate result, a big sample size of subject is required.

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