The document summarizes research on the settling process of cassava starch particles in rectangular channels used in Colombian starch industries. It describes the background of cassava starch production in Colombia, the aim to evaluate sedimentation in the channels, methods to determine slurry concentration changes and particle size distribution, findings that settling of discrete particles predominated and flow varied between 0.82-1.44 L/s, and the conclusion that particles greater than 10 μm were efficiently retained while smaller particles between 6.7-8.8μm were discharged into local waterways.

1. LAURA FIGUEROA RODRIGUEZ 11-3 JM
LIC. En ingles MARINA VIANA MUÑOZ.

3. • Un abstract o resumen del trabajo científico es la parte más importante de tu trabajo
de investigación.
• Se redacta en tercera persona y en pasado haciendo referencia a la investigación
realizada.
• Tiene contenido significativo y conclusiones del material de fuente primaria.
• Debe ser inteligible, es decir, esplique el estudio sin necesidad de referirse a la
investigación completa pero no la sustituye.

4. Su estructura es organizada:
• Background/ antecedentes
• aim or purpose of research/ objetivo o propósito de la investigación
• method used/ método utilizado
• Findings, results/ hallazgos / resultados
• conclusion/conclusión

5. 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.

6. 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.

7. 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.

8. 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.

9. 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.

10. 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.

11. 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).

12. 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).

13. 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.

14. 5-conclusion/conclusión
The findings of this study suggest that the age of sexual
debut has implications for the sexual health in young
people.