Ultraviolet and photosynthetically active radiation can both induce photoprotective capacity allowing barley to overcome high radiation stress

The main objective of this study was to determine the effects of acclimation to ultraviolet (UV) and photosynthetically active radiation (PAR) on photoprotective mechanisms in barley leaves. Barley plants were acclimated for 7 days under three combinations of high or low UV and PAR treatments ([UV-PAR-], [UV-PAR+], [UV+PAR+]). Subsequently, plants were exposed to short-term high radiation ;stress (HRS; defined by high intensities of PAR - 1000 mu mol m(-2) s(-1), UV-A - 10 W m(-2) and UV-B 2 W m(-2) for 4 h), to test their photoprotective capacity. The barley variety sensitive to photooxidative stress (Barke) had low constitutive flavonoid content compared to the resistant variety (Bonus) under low UV and PAR intensities. The accumulation of lutonarin and 3-feruloylquinic acid, but not of saponarin, was greatly enhanced by high PAR and further increased by UV exposure. Acclimation of plants to both high UV and PAR intensities also increased the total pool of xanthophyll-cycle pigments (VAZ). Subsequent exposure to HRS revealed that prior acclimation to UV and PAR was able to ameliorate the negative consequences of HRS on photosynthesis. Both total contents of epidermal flavonols and the total pool of VAZ were closely correlated with small reductions in light-saturated CO2 assimilation rate and maximum quantum yield of photosystem II photochemistry caused by HRS. Based on these results, we conclude that growth under high PAR can substantially increase the photoprotective capacity of barley plants compared with plants grown under low PAR. However, additional UV radiation is necessary to fully induce photoprotective mechanisms in the variety Barke. This study demonstrates that UV-exposure can lead to enhanced photoprotective capacity and can contribute to the induction of tolerance to high radiation stress in barley. (C) 2015 Elsevier Masson SAS. All rights reserved.Peer reviewe

Free Your Mind-Unlock Your Inner Creativity

Creativity is a major factor in many careers, subjects, and disciplines. Although many people first assume engineering to be a field of study that does not require any creativity, it is actually an essential tool for successful engineers. The mark of a truly accomplished engineer is the ability to problem-solve effectively; in other words, to generate creative solutions. Although the goal as engineers is to become more creative throughout one’s career, is it even possible to gain creativity? Is creativity an innate quality, or a learned one? Since the engineering process demands creativity, we looked into how creativity can be improved, and how exactly it is used in the engineering design process. We surveyed engineering freshman students to determine how they view themselves and how important they think creativity is in relation to engineering. We then conducted research to see what creativity means to different people, how one can improve creativity according to various theories, and how creative processes have been used in past engineering projects. We presented this information to all sections of a second-semester engineering freshman course and surveyed the students at the beginning and end of the lecture to see how their views changed. We evaluated this data to discover if students perceive creativity as learned or innate and how it affects their idea on engineering. The students showed an improvement in awareness of the importance of creativity in engineering and how often it is used. Many did not change their opinion of themselves with regard to creativity but some actually ranked themselves lower after the presentation, presumably because they realized the extent of how creative some people are, especially in regard to engineering. The other data we analyzed was student responses to short questions. We asked students what qualities they associate with creative people and the most commonly used words were “thinks outside of the box,” “innovative,” “confident,” and “open minded.” We also asked what the best techniques for improving creativity within a group are. The most common answers were “different backgrounds,” “different ideas,” “being comfortable,” and “diversity.” These answers mirrored the overall message we attempted to portray throughout our presentation to a fair degree

Explosion Prevention in the Present Conditions of Production

The article solves some questions of possible approaches to explosion prevention in production plants. In the introductory part it deals with thoughts about the safety of personnel in an industrial plant in areas with an explosion danger. Further, it defines individual views of industrial plants and suggests the means of solving the explosion prevention in industry. In the conclusion it recommends an approach to the described questions and the means of ensuring asystematic development in the field of explosion prevention

Un cáncer con estoperoles

Tesis (Periodismo)La espiral de fracasos internacionales del fútbol chileno: UN CÁNCER CON ESTOPEROLES Un primer lugar sudamericano a nivel de clubes y dos terceras plazas en el ámbito mundial son los únicos éxitos obtenidos por el balompié criollo en toda su historia. Aparte de otras actuaciones al menos decorosas, el balance es catastrófico. Este reportaje tiene el objetivo central de hacer un diagnóstico de este auténtico flagelo y conocer todas las opiniones multidisciplinarias que desmenuzan las causas y postulan soluciones para superarlo