2. 1-Background/ antecedentes
The production of cassava starch in Colombia comes
mainly from the northern region of the Cauca
Department in small agricultural industries known as
“rallanderías”, in which the settling of the slurry
occurs in channels.
3. 2-aim or purpose of research/ objetivo o propósito de
la investigación
the fact that the settling process determines the
capacity of the starch industry, it is important to
evaluate the sedimentation process performed in
rectangular channels (0.3 m high; 0.4 m wide; 165 m
long), which are generally used in the region.
4. 3-method used/ método utilizado
Two main components were evaluated: determination
of the change in the concentration of the slurry entering
the settling zone and determination of the particle size
distribution in the settling zone.
5. 4-Findings, results/ hallazgos / resultados
In relation to the affluent of the channels, it was
found that the concentration of the slurry during
strainer operation was between 0.1 to 6% most of the
time; the settling of discrete particles, for which the
Stokes Law may be applied, predominated. During
the settling process, the flow varied between 0.82 to
1.44 L/s with a predominance of laminar flow and a
hydraulic retention time greater than 150 minutes.
6. 5-conclusion/conclusión
it was concluded that In the first 104m of the channel,
particles greater than 10 μm in size were efficiently
retained; particles between 6,7 to 8,8μm were not
retained and were discharged into local bodies of
water, generating environmental problems.
7. 1-Background/ antecedentes
In Spain young people have their first sexual
intercourse at an earlier age than in other countries;
however, little is known about the relationship
between age of sexual debut and sexual behavior in
this population.
8. 2-aim or purpose of research/ objetivo o propósito de
la investigación
was analyzed sexual practices and methods of
protection depending on the age of sexual debut
among Spanish adolescents who are sexually
experienced (N = 351).
9. 3-method used/ método utilizado
It was found the mean age was 15.9 years (SD = .75,
range: 14-18). Three groups were formed according to
the age of sexual debut reported: early sexual debut
(earlier than 15 years), average (15 years) and late
(later than 15 years).
10. 4-Findings, results/ hallazgos / resultados
The early sexual debut group reported further
mutual masturbation, vaginal intercourse and oral
sex with a higher number of sexual partners than the
rest. Condom use at first intercourse, percentage of
use and consistent condom use was significantly
lower in the early sexual debut group compared to
the others. Sexual debut before 15 years old was
associated with increased risk of sexual infections,
deficit in condom use and increased sexual exposure.