This document discusses two studies:
1) A study of cassava starch production in Colombia which evaluated the sedimentation process in rectangular channels used. It found that particles greater than 10μm were efficiently retained in the first 104m, while particles between 6.7-8.8μm were discharged into local waterways.
2) A study of Spanish adolescents which analyzed sexual practices and protection methods based on age of sexual debut. It found that those with early debut (before 15) reported more partners and less condom use than later debut groups, suggesting early debut increases health risks.
3. The production of cassava starch
in Colombia comes mainly from
the northern region of the Cauca
Departament in small agricultural
industries know as “rallanderías”,
in which the settling of the slurry
occurs in channels.
4. Due to 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 (0.3m high; o.4m
wide; 165m long), which are generally
used in the region.
5. 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.
6. 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.
7. In the first 104m of the channel, particles
greater than 10μm 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.
9. In Spain young people have
their first sexual intercourse
at an earlier age than in
other countries; however,
little is know about the
relationship between age of
sexual debut and sexual
behavior in this population.
10. Sexual practices and methods of
protection are analyzed depending on
the age of sexual debut among Spanish
adolescents who are sexually
experienced (N-351). The mean age was
15,9 years (SD=.75, range: 14-18).
11. 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).
12. The early sexual debut group reported
further mutual masturbation, vaginal
intercourse and oral sex with a higher
number of sexual portners 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.
13. Sexual debut before 15 years old was
assocrated with increased risk of sexual
infections, deficit in condom use and
iincreased sexual exposure. The findings
of this study suggest that the age of
sexual debut has implications for the
sexual health in young people.
