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The objective of this study was to determine which chemical treatment used for disinfecting water in indoor swimming pools had the least impact on users' perceptions of health problems, and which generated the greatest satisfaction with the quality of the water. A survey on satisfaction and perceived health problems was given to 1001 users at 20 indoor swimming pools which used different water treatment methods [chlorine, bromine, ozone, ultraviolet lamps (UV) and salt electrolysis]. The findings suggest that there is a greater probability of perceived health problems, such as eye and skin irritation, respiratory problems and skin dryness, in swimming pools treated with chlorine than in swimming pools using other chemical treatment methods. Pools treated with bromine have similar, although slightly better, results. Other factors, such as age, gender, time of day of use (morning and afternoon) and type of user (competitive and recreational), can also affect the probability of suffering health problems. For all of the above, using combined treatment methods as ozone and UV, or salt electrolysis produces a lower probability of perceived health problems and greater satisfaction.  相似文献   
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The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L).  相似文献   
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Abstract

This paper is intended as an exploration of university faculty and students’ perceptions of a number of dimensions involved in the written composition of academic texts. We analysed the responses to scale 3 in the European Writing Survey (EUWRIT) (in its Spanish version: Encuesta Europea sobre la Escritura Académica, EEEA) by a group of social science and humanities students (n = 1,030) and faculty (n = 230) from nine Spanish universities. We then examined the similarities and differences in their perceptions and established a factorial structure of the different dimensions underlying the writing process. The data indicate that both groups concur in the value assigned to both changing ideas in the course of the composition process (although this process seems to be understood differently by each group) and the revision and feedback processes. The students, however, claim to be involved in more planning and previous reading activities than the teachers perceive them to be. The significance of these results for a process-oriented perspective in academic writing is discussed.  相似文献   
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