This document discusses two separate topics: 1) A study on the sedimentation process of cassava starch in settling channels commonly used in Colombian cassava starch industries. The study evaluated how the concentration of starch slurry changes in the settling zone and measured particle size distribution. 2) A study of sexual risk in Spanish adolescents depending on their age of sexual debut. The study divided adolescents into groups based on early, average, or late sexual debut age and found that those with earlier debut engaged in more risky sexual behaviors and had lower condom use.

1. CASSAVA STARCH
SEPARATION
María Isabel Argote Turizo
GRADO: 11-2 JM

2. BACKGROUND
 The production of cassava starch in Colombia
comes mainly from the northem region of the
Cauca department in small agricultural industries
know as “rallanderias”, in which the setting of the
slurry occfurs in channels.

3. PURPOSE AND AIM
 The fact that the setting process determines the
capacity of the starch industry, it is important to
evaluate the sedimentation process performed in
rectangular channels which are generally used in
the region. 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

4. METHOD USED
 It is important to evaluated te sedimentation
proccess perfome in rectangular chanals (0.3m
high; 0.4m wide; 1.05 long)

5. FINDINGS/ RESULTS
 In relation to the affuent the channels it was found
that the concentration of the slurry strainer
operation was helween 0.1 ti 6% most of the time.

6. CONCLUSION
Cassava starch industry, sedimentation by gravity,
sedimentation channel starch particles.
Keywords: Cassava starch industry,
sedimentation by gravity, sedimentation channels,
starch particles.

7. SEXUAL RISK IN ADOLESCENTS
DEPENDING ON THE AGE OF SEXUAL
DEBUT

8. PURPUSE AND AIM
 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.

9. METHOD USED
 Sexual practices and methods of protection are
analyzed depending on the age of sexual debut
among Spanish adolescents who are sexually
experienced. The mean age was 15.9 years. Three
groups were formed according to the age of sexual
debut reported: early sexual debut , average (15
years) and late (later than 15 years).

10. FINDINGS/ RESULTS
 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.

11. CONCLUSION
The findings of this study suggest that the age of
sexual debut has implications for the sexual health
in young people.
Key words: Sexual debut, Condom use, Sexual risk,
Adolescence.