Comparing two measures of leaf photorespiration rate across a wide range of light intensities

2019 ◽  
Vol 240 ◽  
pp. 153002 ◽  
Author(s):  
Zi-Piao Ye ◽  
Yu-Guo Liu ◽  
Hua-Jing Kang ◽  
Hong-Lang Duan ◽  
Xian-Mao Chen ◽  
...  
Keyword(s):  
Light Intensities ◽  
Wide Range ◽  
Two Measures ◽  
Photorespiration Rate

Relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test

1998 ◽  
Vol 83 (3) ◽  
pp. 963-967 ◽  
Author(s):  
Teresa D. Smith ◽  
Billy L. Smith
Keyword(s):  
Learning Disabled ◽  
Achievement Test ◽  
Wide Range Achievement Test ◽  
Wide Range ◽  
Two Measures ◽  
Individual Achievement ◽  
And Mathematics ◽  
Mean Differences ◽  
Education Resource ◽  
Wide Range Achievement

The present study examined the relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test for a sample of children with learning disabilities in two rural school districts. Data were collected for 87 school children who had been classified as learning disabled and placed in special education resource services. Pearson product-moment correlations between scores on the two measures were significant and moderate to high; however, mean scores were not significantly different on Reading, Spelling, and Arithmetic subtests of the Wide Range Achievement Test 3 compared to those for the Basic Reading, Spelling, and Mathematics Reasoning subtests of the Wechsler Individual Achievement Test. Although there were significant mean differences between scores on Reading and Reading Comprehension and on Arithmetic and Numerical Operations, magnitudes were small. It appears that the two tests provide similar results when screening for reading spelling, and arithmetic.

scholarly journals Combined Effect of Light and Temperature on the Production of Saxitoxins in Cylindrospermopsis raciborskii Strains

Toxins ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 38 ◽  
Author(s):  
Marcella Mesquita ◽  
Miquel Lürling ◽  
Fabiane Dorr ◽  
Ernani Pinto ◽  
Marcelo Marinho
Keyword(s):  
Maximum Growth ◽  
Combined Effect ◽  
Cylindrospermopsis Raciborskii ◽  
Tropical Regions ◽  
Batch Cultures ◽  
Light Intensities ◽  
Cell Quota ◽  
Wide Range ◽  
Lower Light ◽  
Effect Of Light

Cylindrospermopsis raciborskii is a potentially toxic freshwater cyanobacterium that can tolerate a wide range of light and temperature. Due to climatic changes, the interaction between light and temperature is studied in aquatic systems, but no study has addressed the effect of both variables on the saxitoxins production. This study evaluated the combined effect of light and temperature on saxitoxins production and cellular quota in C. raciborskii. Experiments were performed with three C. raciborskii strains in batch cultures under six light intensities (10, 40, 60, 100, 150, and 500 μmol of photons m−2 s−1) and four temperatures (15, 20, 25, and 30 °C). The growth of C. raciborskii strains was limited at lower temperatures and the maximum growth rates were obtained under higher light combined with temperatures equal or above 20 °C, depending on the strain. In general, growth was highest at 30 °C at the lower light intensities and equally high at 25 °C and 30 °C under higher light. Highest saxitoxins concentration and cell-quota occurred at 25 °C under high light intensities, but were much lower at 30 °C. Hence, increased temperatures combined with sufficient light will lead to higher C. raciborskii biomass, but blooms could become less toxic in tropical regions.

Respiration in the light measured by 12CO 2 emission in 13CO 2 atmosphere in maize leaves

2001 ◽  
Vol 28 (11) ◽  
pp. 1103 ◽  
Author(s):  
Francesco Loreto ◽  
Violeta Velikova ◽  
Giorgio Di Marco
Keyword(s):  
Gas Exchange ◽  
Mitochondrial Respiration ◽  
Bundle Sheath ◽  
Gas Exchange Parameters ◽  
Low Light ◽  
Light Intensities ◽  
Wide Range ◽  
Bundle Sheath Cells ◽  
Maize Leaves ◽  
Exchange Parameters

The mitochondrial respiration during photosynthesis is difficult to measure and is indirectly estimated mainly in C 3 plants. Loreto et al. [(1999) Australian Journal of Plant Physiology 26, 733–736] have shown that the emission of 12 CO 2 from illuminated leaves exposed to air containing 13 CO 2 measures photorespiration and mitochondrial respiration in C 3 leaves. This method was used to measure the mitochondrial respiration in illuminated maize leaves. The 12 CO 2 emission was steady after 30 s, a time sufficient to label the CO 2 leakage from bundle sheath cells with 13 CO 2 , but not the mitochondrial respiration in the light. The emission was low (0.1–0.4 ppm or 0.2–0.4 µmol m –2 s –1 ) in a wide range of leaf temperatures and light intensities, but increased at light intensities below 200 µmol m –2 s –1 and at temperatures above 42°C. At 120 s after labelling, the leaf was darkened and the emission rapidly matched the mitochondrial respiration measured by gas exchange. The emission of 12 CO 2 in the light was inversely correlated with photosynthesis. This suggested that most of the respiratory CO 2 was refixed by photosynthesis. The amount of refixed intercellular 12 CO 2 was calculated from gas-exchange parameters. It was 60 to 90% of the tota l12 CO 2 in leaves illuminated and exposed to temperatures below 42°C. In leaves with reduced photosynthesis because of exposure to higher temperatures or low light, the 12 CO 2 refixation decreased. The sum of refixed and emitted 12 CO 2 was close to the mitochondrial respiration in the dark. This suggested that in these leaves the mitochondrial respiration was not inhibited in the light. In salt- and water-stressed leaves, however, the sum of refixed and emitted 12 CO 2 was lower than mitochondrial respiration in the dark, suggesting that the mitochondrial respiration may be inhibited in the light.

scholarly journals The dynamic nonlinear behavior of fly photoreceptors evoked by a wide range of light intensities

1993 ◽  
Vol 65 (2) ◽  
pp. 832-839 ◽  
Author(s):  
A.S. French ◽  
M.J. Korenberg ◽  
M. Järvilehto ◽  
E. Kouvalainen ◽  
M. Juusola ◽  
...  
Keyword(s):  
Nonlinear Behavior ◽  
Light Intensities ◽  
Wide Range

Growth kinetics of Marquis wheat. II. Carbon dioxide dependence

1972 ◽  
Vol 50 (4) ◽  
pp. 883-889 ◽  
Author(s):  
F. D. H. Macdowall
Keyword(s):  
Carbon Dioxide ◽  
Light Intensity ◽  
Carbon Dioxide Concentration ◽  
Dry Weight ◽  
Maximum Growth ◽  
Carbon Dioxide Enrichment ◽  
Low Light ◽  
Growth Coefficient ◽  
Light Intensities ◽  
Wide Range

Marquis wheat was grown in growth rooms with four different concentrations of carbon dioxide and four to seven different intensities of light in a 16-h photoperiod at 25 °C. Growth was expressed quantitatively as the pseudo-first-order rate coefficient. Carbon dioxide stimulated growth, but the effect was greater the lower the light intensity in opposition to the known effect on photosynthesis. Carbon dioxide and light, in effect, did not influence the "rate" of growth of wheat additively but, rather, mutually compensated over a wide range. The growth coefficient of the roots was a little less than that of the shoots at all carbon dioxide concentrations and light intensities, probably owing to the cost of translocation. However, root growth benefited most from carbon dioxide enrichment at low light intensities. At intermediate light intensity there appeared to be a carbon dioxide concentration optimal for shoot growth. Carbon dioxide enrichment did not influence the maximum growth coefficient of Marquis wheat with respect to light intensity. The light-using efficiency of growth, calculated for vanishingly low light intensity at which it is maximal, was maximal for shoots at 1300 ppm CO2 but that for laminal area and root dry weight increased with CO2 to 2200 ppm at which the value for "leaves" was nearly fourfold that for roots. Unlike photosynthesis, the stimulation of growth by raised CO2 concentration was accomplished by increased efficiency of, and not capacity for, the net photosynthetic use of light.

scholarly journals Photoreceptor Signaling: Supporting Vision across a Wide Range of Light Intensities

2011 ◽  
Vol 287 (3) ◽  
pp. 1620-1626 ◽  
Author(s):  
Vadim Y. Arshavsky ◽  
Marie E. Burns
Keyword(s):  
Light Intensities ◽  
Wide Range

scholarly journals Photosynthetic performance of two freshwater red algal species

2018 ◽  
Vol 77 (2) ◽  
pp. 135-140 ◽  
Author(s):  
Tamás Pálmai ◽  
Beáta Szabó ◽  
Katalin Eszter Hubai ◽  
Judit Padisák
Keyword(s):  
Algal Species ◽  
Photosynthetic Performance ◽  
Lake Balaton ◽  
Light Intensities ◽  
Wide Range ◽  
Red Algal ◽  
Bangia Atropurpurea ◽  
Photosynthetic Performances ◽  
Increasing Temperature ◽  
Temperature Optima

Abstract Photosynthetic performances of two freshwater red algal populations from freshwaters of the Carpathian basin were measured in this study. Populations were collected from different habitats: Bangia atropurpurea from Lake Balaton and Batrachospermum gelatinosum from the Tapolca stream. Their photosynthesis was studied in a wide range of temperature (5–35 °C) and light intensity (0–1150 μmol m−2 s−1) in a photosynthetron. We found both species’ photosynthesis maxima at 25 °C but B. atropurpurea had significantly higher photosynthetic production. Low and medium values were calculated for the species’ photoadaptation parameters. Compensation light intensities determined in this study were similar to those obtained in previous studies. Both species utilized light efficiently; photoinhibition was detected only at two measuring temperatures for Bangia and at four measuring temperatures for Batrachospermum. P-T characteristics of the species revealed that both have temperature optima at 25 °C under high and medium light intensities but there are no such remarkable optima at low irradiance. The biomass specific respiration of both species increased with increasing temperature. We confirmed the good light utilization of these red algal species but found temperature optima higher than reported previously.

scholarly journals Rod photoreceptors drive circadian photoentrainment across a wide range of light intensities

2010 ◽  
Vol 13 (9) ◽  
pp. 1107-1112 ◽  
Author(s):  
Cara M Altimus ◽  
Ali D Güler ◽  
Nazia M Alam ◽  
A Cyrus Arman ◽  
Glen T Prusky ◽  
...  
Keyword(s):  
Rod Photoreceptors ◽  
Light Intensities ◽  
Wide Range

Neutrophil–lymphocyte ratio – a simple, accessible measure of inflammation, morbidity and prognosis in psychiatric disorders?

2020 ◽  
Vol 28 (4) ◽  
pp. 454-458 ◽  
Author(s):  
Zlatan Zulfic ◽  
Cynthia Shannon Weickert ◽  
Thomas W Weickert ◽  
Dennis Liu ◽  
Nicholas Myles ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Inflammatory Marker ◽  
Psychiatric Research ◽  
Neutrophil Lymphocyte Ratio ◽  
Lymphocyte Ratio ◽  
Wide Range ◽  
Inflammatory Phenotype ◽  
Inflammatory Processes ◽  
Two Measures ◽  
Psychiatric Conditions

Objective: A narrative review to describe the utility of the neutrophil-lymphocyte ratio (NLR) as an inflammatory marker in psychiatric and non-psychiatric disorders and to discuss the potential role of NLR in psychiatric research. Conclusions: NLR is inexpensive and readily available using division of two measures obtained on routine blood testing. NLR is elevated in a number of psychiatric disorders. It can predict morbidity and mortality in a wide range of non-psychiatric conditions, but this has not been confirmed in psychiatric conditions. It can be calculated in large, pre-existing datasets to investigate clinical correlates of inflammatory processes. NLR may have a future role in identifying patients with an inflammatory phenotype who could benefit from adjunctive anti-inflammatory medications.

Relationship between Reading Scores on the Wide Range Achievement Test and the Gilmore Oral Reading Test in Young Children

1981 ◽  
Vol 49 (1) ◽  
pp. 191-193 ◽  
Author(s):  
Rita Hollensworth ◽  
Robert B. White
Keyword(s):  
Oral Reading ◽  
Achievement Test ◽  
Reading Test ◽  
Reading Scores ◽  
Wide Range Achievement Test ◽  
Wide Range ◽  
Two Measures ◽  
The Difference ◽  
Grade Placement ◽  
Wide Range Achievement

The relationship between the reading scores of children ages 7 to 9 yr. on the Wide Range Achievement Test and the Gilmore Oral Reading Test was investigated. The 50 children (37 males and 13 females) had a mean age of 8.6 yr., and a mean grade placement of 2.98. They obtained a mean grade level reading score of 3.27 on the achievement test and 2.26 on oral reading (accuracy). Although the correlation between the two scores was .87, 47 of the children scored higher on the achievement test. As the difference between the mean scores on the two tests was significant, it appears that the two measures produce neither identical nor interchangeable information.

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