Irradiation stress

Figure 7. Intermittent stress application during irradiation. Stress was applied for first 12 seconds of each minute during irradiation...

Neidhardt J, Benemann JR, Zhang L, Melis A. (1998). Photosystem II repair and chloroplast recovery from irradiance stress relationship between chronic photoinhibition, light-harvesting chlorophyll antenna size and photosynthetic productivity in Dunaliella salina (green algae). Photosynth. Res. 56, 175-184. 

Smith BM, Morrissey PJ, Guenther JE, Nemson JA, Harrison MA, Allen JF and Melis A. (1990). Response of the photosynthetic apparatus in Dunaliella salina (green algae) to irradiance stress. Plant Physiol. 93, 1433-1440. 

Webb MR and Melis A. (1995). Chloroplast response in Dunaliella salina to irradiance stress. Effect on thylakoid membrane assembly and function. Plant Physiol. 107, 885-8930... 

Experiments were run to evaluate the effects of low level static (stretch) and dynamic (ultrasonic Irradiation) stress on water permeation of a WRT Neoprene. At the same time, the contribution of a partial silica filler In the place of black was determined. The materials were Identical zinc oxlde-magne-slum oxide-cured formulations except that one contained 30 phr black and the other contained 15 phr black and 15 phr silica. These were molded Into cups with 0.030 In. thick faces and 0.070 In. thick side walls which were then fitted over 3.5X salt water-filled glass cups and sealed with hose clamps. 

Masuda T, Polle JEW and Melis A (2002) Biosynthesis and distribution of chlorophyll among the photosystems during recovery of the green alga Dunaliella salina from irradiance stress. Plant Physiol. 128 603-614... 

The influencing of BuChE activity by gamma-irradiation, stress, gravidity, some neurological and psychiatric disorders, hormones, and medical drugs has been demonstrated (B2, B4, B38). The elevation of BuChE activity is not so frequent an increase in children with nephritic syndrome has been observed (W4) an elevated ratio of BuChE/LDL cholesterol indicates an increase in the risk of cardiovascular diseases (K46, N4). The involvement of BuChE with the fat (cholesterol) metabolism has been suggested by van Lith et al. (V6, V7). The relationship between BuChE activity and experimentally induced diabetes mellitus in rats was also mentioned (A 10). 

TorziUo G, Accolla P, Pinzani E, MasojidekJ In situ monitoring of chlorophyll fluorescence to assess the synergistic effect oflow temperature and high irradiance stresses in Spiruhna cultures grown outdoors in photobioreactors, J pp/ Phycol 8(4—5) 283-291, 1996. 

Irradiation positions in neutron beams extracted from reactors are most conunonly used for PGAA. These positions offer a major advantage namely the samples do not require packaging to withstand mechanical and irradiation stresses, i.e., containment can be minimal or is not required at all. In principle, samples are not limited to a certain size and shape, except by the physical space in the irradiation position, which commonly has shielding elements put in place to protect persormel. Nevertheless, irradiation of entire paintings has been demonstrated (Fischer et al. 1987). 

Transformations in the Solid State. From a practical standpoint, the most important soHd-state transformation of PB involves the irreversible conversion of its metastable form II developed during melt crystallization into the stable form I. This transformation is affected by the polymer molecular weight and tacticity as well as by temperature, pressure, mechanical stress, and the presence of impurities and additives (38,39). At room temperature, half-times of the transformation range between 4 and 45 h with an average half-time of 22—25 h (39). The process can be significantly accelerated by annealing articles made of PB at temperatures below 90°C, by ultrasonic or y-ray irradiation, and by utilizing various additives. Conversion of... 

Graphite will creep imder neutron irradiation and stress at temperatures where thermal creep is normally negligible. The phenomenon of irradiation creep has been widely studied because of its significance to the operation of graphite moderated fission reactors. Indeed, if irradiation induced stresses in graphite moderators could not relax via radiation creep, rapid core disintegration would result. The observed creep strain has traditionally been separated into a primary reversible component ( ,) and a secondary irreversible component (Ej), both proportional to stress and to the appropriate unirradiated elastic compliance (inverse modulus) [69]. The total irradiation-induced creep strain (ej is thus ... 

Essential for induction ofthe/Z-5 gene in inflammatory reactions is the binding site for nuclear factor kappa B (NF-kB). NF-kB responds to cytokines, stress, free radicals, ultraviolet irradiation, and bacterial, viral, or even parasitic antigens [2]. NF-kB stands for a family of subunits, which form homo-, and heterodimers. All NF-kB proteins share a highly conserved DNA-binding/dimerization domain called the Rel homology domain (RHD) consisting of two (3-strand core domains... 

Aqueous plutonium photochemistry is briefly reviewed. Photochemical reactions of plutonium in several acid media have been indicated, and detailed information for such reactions has been reported for perchlorate systems. Photochemical reductions of Pu(VI) to Pu(V) and Pu(IV) to Pu(III) are discussed and are compared to the U(VI)/(V) and Ce(IV)/(III) systems respectively. The reversible photoshift in the Pu(IV) disproportionation reaction is highlighted, and the unique features of this reaction are stressed. The results for photoenhancement of Pu(IV) polymer degradation are presented and an explanation of the post-irradiation effect is offered. 

At low irradiances, photosynthesis uses virtually 100% of the quanta, but in full sunlight, about 2000 imol quanta s , more quanta are available than can be used in photochemistry. Maximum rates of photosynthesis by Populus or Spinacia leaves of 15 and 70 jumol O2 m s , respectively, would require only 15 x 9 = 135 to 630 jumol quanta m s , or 10-40%. Leaves, therefore, need to be able to dissipate 60-90% of the quanta at high irradiance in an orderly manner such as non-radiative decay if they are to avoid the potentially damaging formation of oxygen radicals from reduced ferredoxin (Asada Takahashi, 1987). When plants are under a stress that restricts CO2 assimilation, excessive light will be reached at even lower irradiances. 

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