PHYSIOLOGICAL BASIS OF DIFFERENTIAL SENSITIVITY OF FISH EMBRYONIC STAGES TO OIL POLLUTION

1979 ◽  
pp. 85-108 ◽  
Author(s):  
J.R. Sharp ◽  
K.W. Fucik ◽  
J.M. Neff
Keyword(s):  
Oil Pollution ◽  
Differential Sensitivity ◽  
Physiological Basis

scholarly journals DRIVER CHARACTERISTICS AND THEIR IMPACT UPON VEHICLE TRAFFIC SAFETY

2021 ◽  
Vol 2021 (1) ◽  
pp. 34-42
Author(s):  
Evgeniy Khristoforov ◽  
Nataliya Sakovich
Keyword(s):  
Traffic Safety ◽  
Degrees Of Freedom ◽  
Professional Training ◽  
Road Traffic ◽  
Physiological State ◽  
Practical Importance ◽  
Differential Sensitivity ◽  
Traffic Information ◽  
Physiological Basis ◽  
The Impact

Of all the variety of operator’s activities a motor car driver’s work is difficult enough. It is stipulated by a number of reasons, for example, one has to control an object with some degrees of freedom, sometimes under conditions of time shortage and often in stress situations. At that the work of a driver continues to become more and more complicated, and the number of errors and their consequences grow. The work purpose: to investigate the impact of problems in vehicle control by a driver upon his health and reliability, to investigate mental and physiologic properties of a driver, the impact of his organs of sense upon reception and processing traffic information and vehicle driving. The investigations were carried out on the basis of methods described by Weber-Fechner’s law which expresses dependence between an objective value of irritation and subjective value characterizing the sensation of this irritation, by Walter’s law which offered a concept of the dynamic threshold of differential sensitivity, in the information reception take part mental processes – sensation, perception and thinking. In the paper there are described positive and negative driver’s properties on vehicle driving, at that considerable attention is paid to the matter of the impact of a mental and physiological state of driver’s constitution upon the reception and processing of information for the formation and realization of stable skills in driving using at that almost all sense organs. It is defined that at the reception of road traffic information by a driver there is formed in him an image reflecting in his consciousness a controlled process. As a physiological basis of the formation of this image is the activity of analyzers – a system consisting of three links: a receptor conducting nervous ways and an area of cerebrum, as a result of this there is formed an image in the driver which reflects in driver’s consciousness a controlled process that is a scientific novelty on the topic investigated. Research materials are of practical importance for the professional selection of drivers, their qualitative professional training as a result of that a driver will be capable to solve the most complex problems in ensuring traffic safety.

Physiological basis for nicosulfuron and primisulfuron selectivity in five plant species

Weed Science ◽  
1997 ◽  
Vol 45 (1) ◽  
pp. 22-30 ◽  
Author(s):  
J. Boyd Carey ◽  
Donald Penner ◽  
James J. Kells
Keyword(s):  
Plant Species ◽  
Acetolactate Synthase ◽  
Differential Sensitivity ◽  
Lower Sensitivity ◽  
Plant Responses ◽  
Physiological Basis ◽  
Eastern Black Nightshade ◽  
Black Nightshade ◽  
Giant Foxtail ◽  
Whole Plant

Greenhouse and laboratory studies were conducted to determine the physiological basis for selectivity of nicosulfuron and primisulfuron in 5 plant species. Differential sensitivity of the species was quantified by determining GR50values (herbicide rate required to reduce plant growth 50%) for each species/herbicide combination. GR50data indicated the following levels of sensitivity: corn—tolerant to both herbicides; seedling johnsongrass—sensitive to both herbicides; barnyardgrass—sensitive to nicosulfuron and tolerant to primisulfuron; giant foxtail—sensitive to nicosulfuron and tolerant to primisulfuron; and eastern black nightshade—tolerant to nicosulfuron and sensitive to primisulfuron. Studies using14C-radiolabeled herbicides were conducted to determine whether differential herbicide absorption, translocation, or metabolism contributed to whole plant responses. Nicosulfuron and primisulfuron selectivity in corn, johnsongrass, barnyardgrass, and giant foxtail was primarily due to differential herbicide metabolism rate. Tolerant species metabolized the herbicide more rapidly and extensively than sensitive species. Differential herbicide absorption, translocation, or metabolism did not explain differential sensitivity of eastern black nightshade to the herbicides. Further studies indicated that the tolerance of eastern black nightshade to nicosulfuron and its sensitivity to primisulfuron was directly related to lower sensitivity of the acetolactate synthase (ALS) to nicosulfuron than to primisulfuron. Eastern black nightshade translocated very little (3%) of the nicosulfuron applied. The ALS sensitivity of johnsongrass and eastern black nightshade was similar in the presence of nicosulfuron. A combination of a higher ALS level and less herbicide translocation contributes to tolerance of eastern black nightshade and to sensitivity of johnsongrass to nicosulfuron.

Conservative water use under high evaporative demand associated with smaller root metaxylem and limited trans-membrane water transport in wheat

2014 ◽  
Vol 41 (3) ◽  
pp. 257 ◽  
Author(s):  
Rémy Schoppach ◽  
Diego Wauthelet ◽  
Linda Jeanguenin ◽  
Walid Sadok
Keyword(s):  
Water Use ◽  
Cross Sections ◽  
Water Conservation ◽  
Vapour Pressure Deficit ◽  
Differential Sensitivity ◽  
Mercury Chloride ◽  
Evaporative Demand ◽  
Physiological Basis ◽  
Drought Tolerant ◽  
Efficient Breeding

Efficient breeding of drought-tolerant wheat (Triticum spp.) genotypes requires identifying mechanisms underlying exceptional performances. Evidence indicates that the drought-tolerant breeding line RAC875 is water-use conservative, limiting its transpiration rate (TR) sensitivity to increasing vapour pressure deficit (VPD), thereby saving soil water moisture for later use. However, the physiological basis of the response remains unknown. The involvement of leaf and root developmental, anatomical and hydraulic features in regulating high-VPD, whole-plant TR was investigated on RAC875 and a drought-sensitive cultivar (Kukri) in 12 independent hydroponic and pot experiments. Leaf areas and stomatal densities were found to be identical between lines and de-rooted plants didn’t exhibit differential TR responses to VPD or TR sensitivity to four aquaporin (AQP) inhibitors that included mercury chloride (HgCl2). However, intact plants exhibited a differential sensitivity to HgCl2 that was partially reversed by β-mercaptoethanol. Further, root hydraulic conductivity of RAC875 was found to be lower than Kukri’s and root cross-sections of RAC875 had significantly smaller stele and central metaxylem diameters. These findings indicate that the water-conservation of RAC875 results from a root-based hydraulic restriction that requires potentially heritable functional and anatomical features. The study revealed links between anatomical and AQP-based processes in regulating TR under increasing evaporative demand.

Physiological Basis for Differential Sensitivity to Sulfentrazone by Sicklepod (Senna obtusifolia) and Coffee Senna (Cassia occidentalis)

Weed Science ◽  
1996 ◽  
Vol 44 (1) ◽  
pp. 12-17 ◽  
Author(s):  
Franck E. Dayan ◽  
John D. Weete ◽  
H. Gary Hancock
Keyword(s):  
Parent Compound ◽  
Leaf Tissue ◽  
High Sensitivity ◽  
High Rate ◽  
Differential Sensitivity ◽  
Physiological Basis ◽  
Shoot Height ◽  
Cassia Occidentalis ◽  
Root Exposure ◽  
Greenhouse Tests

Consistent with field observations, sicklepod exhibited considerable tolerance to sulfentrazone, and coffee senna showed relatively high sensitivity to this herbicide in greenhouse tests. Germination was not inhibited in either species at up to 12.9 μM of the herbicide. However, the chlorophyll content of herbicide-treated coffee senna cotyledonary leaves was greatly reduced, and seedlings died within 10 d after treatment, while sicklepod seedlings were not visibly affected. Shoot height of coffee senna was inhibited 90% by sulfentrazone at 0.5 kg ai ha−1, while the growth of sicklepod was not affected up to 2.0 kg ai ha−1. Root uptake of radiolabeled sulfentrazone was 74% greater in coffee senna than sicklepod, but the amount of radioactivity recovered from the shoots of both species after 12 h was not different. Eighty-three percent of the parent compound remained in coffee senna leaf tissue after 9 h root exposure to the herbicide. In contrast, sicklepod took up relatively less sulfentrazone through the root and metabolized sulfentrazone in the foliage more rapidly than coffee senna, with 91.6% of the herbicide being metabolized during the first 9 h of exposure. These results suggest that the tolerance of sicklepod to sulfentrazone is primarily due to a relatively high rate of metabolism of the herbicide compared to coffee senna.

Ultrastructural Changes in Three Different Mammalian Cells Following Ultraviolet Laser Irradiation

1972 ◽  
Vol 30 ◽  
pp. 350-351
Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki
Keyword(s):  
Ultraviolet Light ◽  
Mammalian Cells ◽  
Biological Effects ◽  
Survival Rates ◽  
Chinese Hamster ◽  
Cell Types ◽  
Differential Sensitivity ◽  
Ultrastructural Changes ◽  
Ultraviolet Laser

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.

How to Psychologically Minimize Scratching Impulses

2014 ◽  
Vol 222 (3) ◽  
pp. 140-147 ◽  
Author(s):  
Ariane Sölle ◽  
Theresa Bartholomäus ◽  
Margitta Worm ◽  
Regine Klinger
Keyword(s):  
Cognitive Processes ◽  
Placebo Effect ◽  
Psychological Factors ◽  
Pharmacological Treatments ◽  
Physiological Basis ◽  
Psychological Mechanisms ◽  
Physical Complaints ◽  
Factors Influencing ◽  
The Impact ◽  
Placebo Model

Research in recent years, especially in the analgesic field, has intensively studied the placebo effect and its mechanisms. It has been shown that physical complaints can be efficiently reduced via learning and cognitive processes (conditioning and expectancies). However, despite evidence demonstrating a large variety of physiological similarities between pain and itch, the possible transfer of the analgesic placebo model to itch has not yet been widely discussed in research. This review therefore aims at highlighting potential transfers of placebo mechanisms to itch processes by demonstrating the therapeutic issues in pharmacological treatments for pruritus on a physiological basis and by discussing the impact of psychological mechanisms and psychological factors influencing itch sensations.

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