5-Aminolevulinic acid (ALA), a newly proved natural plant growth regulator, is well known to improve plant photosynthesis under both normal and stressful conditions. However, its underlying mechanism remains largely unknown. Stomatal closure is one of the major limiting factors for photosynthesis and abscisic acid (ABA) is the most important hormone in provoking stomatal closing. Here, we showe...

Stomata play a key role in the control of plant water relations and photosynthesis. A rapid non-destructive method to study the stomatal behaviour in aerial parts of plants is important for researchers in plant sciences and agricultural fields. Stomata close in response to drought stress. Stomatal closure causes lower availability of CO2 inside the leaf and thus a decrease in the rate of carbox...

This paper examines whether there is a causal relationship from job displacement to all–cause mortality. The hypothesis is tested for all employees who lost their job due to a plant closure in Sweden in 1987 and 1988. The control group is a random sample of all employees who did not experience a plant closure during the mid 1980s. Apart from variables commonly available in such studies (age, se...

Research in plant hydraulics has provided important insights into plant responses to drought and species absolute drought tolerance. However, our ability to predict when plants will die from hydraulic failure under extreme drought is limited by a lack of knowledge with regards to the dynamics of plant desiccation following stomatal closure. Thus, we develop a simple hydraulics model based on br...

Serving as an important second messenger, calcium ion has unique properties and universal ability to transmit diverse signals that trigger primary physiological actions in cells in response to hormones, pathogens, light, gravity, and stress factors. Being a second messenger of paramount significance, calcium is required at almost all stages of plant growth and development, playing a fundamental...

BACKGROUND In the year 2000 Corus closed its steel plant operations in Redcar, NE of England temporarily for refurbishment of its blast furnace. This study investigates the impact of the closure on the chemical composition and biological activity of PM10 collected in the vicinity of the steel plant. METHODS The metal content of PM10 samples collected before during and after the closure was me...

Gas exchange techniques were used to investigate light-saturated carbon assimilation and its stomatal and non-stomatal limitations over two seasons in mature trees of five species in a closed deciduous forest. Stomatal and non-stomatal contributions to decreases in assimilation resulting from leaf age and drought were quantified relative to the maximum rates obtained early in the season at opti...

In this paper we prove that any distance-balanced graph G with ∆(G) ≥ |V (G)| − 3 is regular. Also we define notion of distancebalanced closure of a graph and we find distance-balanced closures of trees T with ∆(T ) ≥ |V (T )| − 3.