Protección solar en el trabajo asociado a características laborales en trabajadores de Latinoamérica: estudio base / Sun protection at work associated with the job characteristics of Latin America workers: base study

RESUMEN Los efectos nocivos de la radiación solar han sido reportados, pero casi no se ha estudiado la población laboral de Latinoamérica. Este es un estudio transversal analítico realizado en ocho países. Las preguntas sobre protección solar se tomaron de trabajos previos; además, se preguntó por las características laborales; ambos datos se cruzaron para obtener datos estadísticos de asociación. De los 3.222 trabajadores encuestados, el 71% (2270) tenía piel mestiza. Hubo asociación del enrojecimiento de la piel según la cantidad de horas de exposición solar directa (p<0,001) e indirecta (p<0,001). El 47% (995) usaban protector/bloqueador solar, el 54% (1150) usaban ropa adecuada y el 50% (1056) usaban alguna gorra o sombrero; siendo estadísticamente diferente el medio de adquisición de dichos equipos. El 21% (446) no usaba ninguno de los equipos de protección personal ante los efectos del sol. Concluimos que es alarmante el bajo porcentaje de trabajadores que reciben adecuada protección contra los efectos de la radiación solar. Esto podría generar problemas a corto, mediano y largo plazo entre los empleados, lo que podría aumentar la morbi-mortalidad y el riesgo de cáncer de piel.

ABSTRACT The harmful effects of solar radiation have been reported, but the work population in Latin America has hardly been studied. The objective is describe the type of sun protection they use and find associations according to their characteristics in Latin American workers. The methodology isCross-sectional analytical study carried out in 8 countries, the questions of sun protection were taken from previous work, in addition, asked about the labor characteristics; Both were crossed to obtain association statistics. Our results: Of the 3.222 workers surveyed, 71% (2270) had mestizo skin. There was association of skin redness according to the number of hours of direct (p <0.001) and indirect sun exposure (p <0.001). 47% (995) wore the sunscreen / protector, 54% (1150) wore appropriate clothing and 50% (1056) wore a cap or hat; statistically different according to the means of acquisition of such equipment (p value <0.001 for all three cases). 21% (446) did not wear any personal protective equipment to the effects of the sun. It is alarming that the low percentage of workers who receive adequate protection against the effects of solar radiation can cause problems in the short, medium and long term among employees. This could increase morbidity and mortality and the risk of skin cancer. It is important to do more research in this regard, as this issue is of utmost importance because of the changes that have occurred in radiation levels, which could generate a public health problem in this work group.

[Knowledge of sexually transmitted diseases and attitudes towards them in populations at risk in Djibouti]. / Connaissances et attitudes envers les maladies sexuellement transmissibles dans des populations à risque à Djibouti.

Sexually transmitted diseases (STDs) are an increasing public health problem in Djibouti. The authors have attempted to obtain basic information on the level of knowledge concerning STDs and on the sexual behaviour of highly sexually promiscuous individuals for use in the organization of future STD control programmes; the information was obtained from a population of 213 bar hostesses, 66 unlicensed prostitutes, and 115 male sufferers from STDs. The level of knowledge of these diseases was very high among the prostitutes and the bar hostesses, except that little was known about syphilis by the bar hostesses; the male sufferers were relatively ignorant concerning both syphilis and AIDS. Medical and paramedical personnel do not figure among the sources given for knowledge of STDs. On the other hand, friends play an important role in this knowledge, especially among unlicensed prostitutes. The second most frequently instanced source was radio and TV. The bar hostesses and the unlicensed prostitutes often exhibited distinct social characteristics. Neither education nor marriage appeared to prevent men from contracting STDs. The use of condoms is extremely rare among STD patients and not very common among unlicensed prostitutes. Half the bar hostesses report their frequent use.

Predicting the potential of open-pollinating populations for the production of superior F1 hybrids.

The distributive properties of a single population or of a population resulting from a cross between two populations are reproduced when inbreds randomly extracted from the population itself or from the two parental populations are randomly paired. Hence, population parameters that are usually obtained during a breeding programme can be used to predict the performance of the F1 hybrids that can be derived from them at that stage. Multiple allelism, epistasis and deviations from Hardy-Weinberg equilibria should not cause biasis to the predictions. While in theory genotype x environment interaction and linkage disequilibrium may disturb the predictions, in practice they are unlikely to create problems that cannot be accommodated. Genotypic and phenotypic predictions of the proportions of the F1 hybrid distribution scoring above or below a given standard are made and analysed for three characters, weight of the ears, plant height and height of the ear, in two populations of maize per se and their interpopulational cross. Because no random inbred lines from the experimental populations are presently available we cannot check our predictions. However, genotypic and phenotypic predictions and observations of F1 hybrids obtained from populations created by computer simulation are provided to illustrate our procedures.

Predicting the properties of second cycle hybrids produced by intercrossing random samples of recombinant inbred lines.

Distributive properties of the second cycle hybrids that are produced by inter-crossing the recombinant inbreds extractable from the F2 of a cross between two pure breeding lines can be predicted from the early generations of the original cross. Hence the frequency of such hybrids that will outperform the extreme recombinant inbreds or the original F1 can be predicted. Basic generations and triple test cross families provide the most reliable estimates of the predictors and therefore should be used whenever possible although, in the presence of linkage, randomly mated F2's may give improved predictions. Simpler experiments consisting of the parental varieties and their F1 and F2 generations, however, provide all the information that is likely to be necessary for most practical purposes. The predictive power of the new approach is demonstrated on material extracted from the cross of varieties 1 and 5 of Nicotiana rustica. The predictors were estimated from the means and variances of V1, V5, F1 and F2 raised in six environments between 1973 and 1983. The predicted frequencies of second cycle F1's which outperform the extreme recombinant inbred lines derived from this cross are compared with those observed among 190 second cycle hybrids in a diallel between 20 recombinant inbreds derived from the same cross.