data envelopment analysis (dea) measures the relative efficiency of decision making units (dmus) with multiple inputs and multiple outputs. dea-based malmquist productivity index measures the productivity change over time. we propose a dynamic dea model involving network structure in each period within the framework a dea. we have previously published the network dea (ndea) and the dynamic dea ...

one of the most popular approaches to measuring productivity changes is based on using malmquist productivity indexes. in this paper we propose a method for obtaining interval malmquist productivity index (impi). the classical dea models have been before used for measuring the malmquist productivity index. the current article extends dea models for measuring the interval malmquist productivity ...

All preceding investigations on the quantum efficiency of photosynthesis, starting with the early experiments of Warburg and Negelein (1922a, b) and Emerson and Lewis (1939, 1941) are performed under low irradiances, even under light compensation point, assuming that the photosynthetic “light curves” are linear and the quantum efficiency of photosynthesis is maximum under these conditions. Howe...

Photosynthesis is the source of our food and fiber. Increasing world population, economic development, and diminishing land resources forecast that a doubling of productivity is critical in meeting agricultural demand before the end of this century. A starting point for evaluating the global potential to meet this goal is establishing the maximum efficiency of photosynthetic solar energy conver...

C(4) photosynthesis has evolved more than 60 times as a carbon-concentrating mechanism to augment the ancestral C(3) photosynthetic pathway. The rate and the efficiency of photosynthesis are greater in the C(4) than C(3) type under atmospheric CO(2) depletion, high light and temperature, suggesting these factors as important selective agents. This hypothesis is consistent with comparative analy...

in order to investigate the responses of sardari wheat ecotypes to drought stress, 12 spikes of sardari wheat were selected from different regions of kurdistan province and planted as head to row. in the second year, a split- plot factorial field experiment was conducted. in this experiment water stress and irrigation were considered as the levels of main factor and 12 sardari wheat ecotypes al...

In plants, genes involved in photosynthesis are encoded separately in nuclei and plastids, and tight cooperation between these two genomes is therefore required for the development of functional chloroplasts. Golden2-like (GLK) transcription factors are involved in chloroplast development, directly targeting photosynthesis-associated nuclear genes for up-regulation. Although overexpression of G...

The photosynthetic responses of four alfalfa (Medicago sativa L.) cultivars to 10 and 22 C air temperatures were examined and the relationship between the photosynthetic response at 10 C and the fatty acid composition of the chloroplast membranes was determined. Chilling-resistant cultivars exhibited moderate reductions in photosynthesis at 10 C, compared to 22 C, and contained a significantly ...

in order to investigate of the effects of water stress on seed yield and gas exchange and to evaluate the relationship between source and sink in sunflower azargol variety, a split-plot factorial field experiment was conducted in 2008. in this experiment, water stress (no irrigation from 30 days after sowing till ripening) and irrigation (irrigation at -3 bar soil water potential) were consider...

The absorption spectra of the principal pigment components extracted from Chroococcus cells have been measured, and their sum compared with the absorption of a suspension of living cells. The agreement was sufficiently close so that it was concluded the absorption spectra of the extracted and separated pigment components could be used to obtain estimates of the relative absorption of the variou...