ABSTRACT
Rodentia has a high species number and chromosomal variability. The South American genus Akodon is one of the most speciose muroids, with more than 40 species included in several species groups. Here, we characterize cytogenetically specimens of Akodon from central-western Argentina. Subsequently, we reviewed and analyzed the cytogenetic data for this genus, build a phylogeny and mapped chromosome changes to interpret its evolution. Specimens of A. dolores from central-western Argentina have 2n=42-44/FNa=44 (46, 48) due to a Robertsonian rearrangement. Our data expand the distribution range known for this polymorphism and confirm its geographic structure. Other specimens had 2n=40/FNa=40, representing populations of A. oenos, A. polopi, and A. spegazzinii. All karyotypes have a low amount of heterochromatin, concentrated in centromeres and sex chromosomes, as in other rodents. The complement with 2n=40/FNa=40 is the most frequent in Akodon and is shared by most species in some groups. Chromosome numbers are very diverse. The FNa shows less variability; FNa=42 was recovered as ancestral, excluding A. mimus, which was connected at the base of the Akodon tree and has FNa=44. This indicates a complex chromosome evolution in Akodon, and suggests that reductions and increases in the 2n and FNa evolved independently in some lineages.
Subject(s)
Rodentia , Sigmodontinae , Animals , Argentina , Karyotyping , Phylogeny , Sex ChromosomesABSTRACT
Abstract Introduction: Different developmental and environmental vulnerability conditions can influence violent behavior in young people. Objectives: To describe the characteristics of young males who were convicted of murder or attempted murder in the province of Buenos Aires, based on indicators of maturity, impulsivity, and socio-family vulnerability. Materials and Methods: Descriptive and exploratory study. The sample consisted of 195 young men (mean: 16.8 years) imprisoned in reformatory institutions of the Province of Buenos Aires, Argentina, as they were convicted of murder (n=130), repeated murder (n=15), or attempted murder (n=50). Self and hetero-informed instruments, and professional assessment scales were used, namely: the Consideration of Future Consequences Scale (CFC); the Psychosocial Maturity Inventory (PSM); the Weinberg Adjustment Inventory (WAI); the Resistance to Peer Influence Questionnaire (RPIQ); the Psychopathy Checklist: Youth Version (PCL:YV); the Inventory of Callous Unemotional Traits (ICU), and the Barrat Impulsiveness Scale version 11 (BIS-11). Results: The distribution of the total BIS 11 and the PSM Individual Adaptation were normal (mean: 62.33 and 6.38, respectively). The mean of the total PCL:YV was 25.87. In 32.8% of the cases a first degree relative was also imprisoned. "Impulsive" and "Non-impulsive" clusters were empirically established. Conclusions: The participants' profile is characterized by several psychological and socio-family vulnerabilities that should be targeted in preventive interventions aimed at preventing violent recidivism.
Resumen Introducción. Diversas condiciones de vulnerabilidad dependientes del desarrollo y de las influencias medioambientales pueden influir en las conductas violentas juveniles. Objetivos. Describir las características de jóvenes que cometieron homicidio o intento de homicidio atendiendo a indicadores de madurez, impulsividad y vulnerabilidad sociofamiliar. Materiales y métodos. Estudio de diseño descriptivo y exploratorio. Los participantes fueron 195 varones jóvenes (media: 16.8 años) institucionalizados en la provincia de Buenos Aires, Argentina, por orden judicial por haber cometido homicidio (n=130), homicidio reiterado (n=15) o tentativa de homicidio (n=50). Se utilizaron instrumentos auto y heteroinformados y las escalas de evaluación profesional Consideration of Future Consequences Scale (CFC), Psychosocial Maturity Inventory (PSM), Weinberg Adjustment Inventory (WAI), Resistance to Peer Influence (RPI), Psychopathy Checklist: Youth Version (PCL:YV), Inventory of Callous Unemotional Traits (ICU) y Barrat Impulsiveness Scale version 11 (BIS 11). Resultados. La distribución de BIS 11 total y de PSM Adecuación Individual fueron normales, con medias de 62.33 y 6.38, respectivamente; la media de PCL: YV total fue 25.87. El 32.8% de los jóvenes tenía familiares de primer grado presos. Se configuraron empíricamente los clusters "impulsivo" y "no impulsivo". Conclusiones. El perfil de los participantes se caracteriza por diversas vulnerabilidades psicológicas y sociofamiliares que deberían ser blanco de intervención preventiva de recidiva violenta.
ABSTRACT
Although knowledge on and prevention of juvenile homicide are crucial for social welfare and have been approached through different methodological instruments, this behavior is still quite difficult to be addressed. In this study, we have analyzed several psychological and social factors that could be theoretically related to juvenile homicidal behavior. Our case-control study included young (M = 16.8 years) males institutionalized in the Province of Buenos Aires, Argentina, under judicial order for crime. Out of 195 cases, 130 had committed homicide, 15 had repeated homicide, and 50 had attempted homicide. The control group comprised 305 young males who had committed other types of crimes. Self-reported and informant-reported instruments and professional assessment were used: Consideration of Future Consequences (CFC) Scale, Weinberger Adjustment Inventory (WAI), Resistance to Peer Influence (RPI), Psychopathy Checklist-Youth Version (PCL-YV), and Inventory of Callous Unemotional Traits (ICU). Differences between indicators of the psychological and social dimensions were not statistically significant. Only Factor 4 of the PCL-YV showed statistically significant difference. However, the relevance of this result is under discussion.
