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1.
Ann Bot ; 133(5-6): 725-742, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38365451

RESUMEN

BACKGROUND AND AIMS: The grass genus Urochloa (Brachiaria) sensu lato includes forage crops that are important for beef and dairy industries in tropical and sub-tropical Africa, South America and Oceania/Australia. Economically important species include U. brizantha, U. decumbens, U. humidicola, U. mutica, U. arrecta, U. trichopus, U. mosambicensis and Megathyrsus maximus, all native to the African continent. Perennial growth habits, large, fast growing palatable leaves, intra- and interspecific morphological variability, apomictic reproductive systems and frequent polyploidy are widely shared within the genus. The combination of these traits probably favoured the selection for forage domestication and weediness, but trait emergence across Urochloa cannot be modelled, as a robust phylogenetic assessment of the genus has not been conducted. We aim to produce a phylogeny for Urochloa that includes all important forage species, and identify their closest wild relatives (crop wild relatives). Finally, we will use our phylogeny and available trait data to infer the ancestral states of important forage traits across Urochloa s.l. and model the evolution of forage syndromes across the genus. METHODS: Using a target enrichment sequencing approach (Angiosperm 353), we inferred a species-level phylogeny for Urochloa s.l., encompassing 54 species (~40 % of the genus) and outgroups. Phylogenies were inferred using a multispecies coalescent model and maximum likelihood method. We determined the phylogenetic placement of agriculturally important species and identified their closest wild relatives, or crop wild relatives, based on well-supported monophyly. Further, we mapped key traits associated with Urochloa forage crops to the species tree and estimated ancestral states for forage traits along branch lengths for continuous traits and at ancestral nodes in discrete traits. KEY RESULTS: Agricultural species belong to five independent clades, including U. brizantha and U. decumbens lying in a previously defined species complex. Crop wild relatives were identified for these clades supporting previous sub-generic groupings in Urochloa based on morphology. Using ancestral trait estimation models, we find that five morphological traits that correlate with forage potential (perennial growth habits, culm height, leaf size, a winged rachis and large seeds) independently evolved in forage clades. CONCLUSIONS: Urochloa s.l. is a highly diverse genus that contains numerous species with agricultural potential, including crop wild relatives that are currently underexploited. All forage species and their crop wild relatives naturally occur on the African continent and their conservation across their native distributions is essential. Genomic and phenotypic diversity in forage clade species and their wild relatives need to be better assessed both to develop conservation strategies and to exploit the diversity in the genus for improved sustainability in Urochloa cultivar production.


Asunto(s)
Filogenia , Brachiaria/genética , Brachiaria/anatomía & histología , Brachiaria/crecimiento & desarrollo , África , Evolución Biológica , Poaceae/genética , Poaceae/anatomía & histología , Genoma de Planta
2.
J Appl Genet ; 65(1): 1-11, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37934380

RESUMEN

Apart from apomictic types, the Polygonum-type eight-nuclear embryo sac is considered to be dominant in grasses. A triploid endosperm is formed as a result of double fertilisation. This study showed, for the first time, the dominance of diploid nuclei in the syncytial stage of the central cell of embryo sac in oat species and amphiploids. The dominance of diploid nuclei, which were the basis for the formation of polyploid nuclei, was weaker in amphiploids due to aneuploid events. The genomic in situ hybridisation method applied in the study did not distinguish the maternal and paternal haploid nuclei of embryo sac. However, this method demonstrated the lack of a set of genomes of one haploid nucleus. Embryological analyses of the initial stages of oat endosperm development revealed a fertilised egg cell, and two polar nuclei differing in size. It can be assumed that the formation of diploid oat endosperm occurred after the fusion of one polar nucleus and the nucleus of a male gamete, while the second polar nucleus gave rise to 1n nuclei. The levels of ploidy of syncytial nuclei were not influenced by both aneuploid events and correlated with pollen developmental anomalies. The differences in the analysed cytogenetic events distinguished amphiploids and their parental species in the ordination space.


Asunto(s)
Diploidia , Endospermo , Endospermo/genética , Avena/genética , Ploidias , Aneuploidia
3.
Eur J Psychotraumatol ; 14(2): 2263321, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37846637

RESUMEN

BACKGROUND: Childhood sexual abuse (CSA) has been identified as a risk factor for later sexual aggression perpetration and vulnerability factor for sexual victimization. However, the use of cross-sectional designs, the focus on female victimization and male perpetration, and the lack of evidence from outside North America limit the existing knowledge base. OBJECTIVE: The study was designed to examine pathways from CSA to sexual revictimization and sexual aggression perpetration after the age of consent. METHOD: A total of 588 university students in Germany (308 female) took part in a three-wave longitudinal study covering 23 months. At each wave (T1-T3), all participants completed measures of sexual aggression victimization and perpetration. Experiences of CSA were measured at T1. RESULTS: The rate of CSA was significantly higher for women (20.8%) than for men (12.4%). Rates of sexual victimization for women were 60.9% at Time 1 (since age 14), 22.3% at Time 2 (since T1), and 17.4% at Time 3 (since T2). For men, the rates were 39.2% at Time 1, 15.9% at Time 2, and 14.1% at Time 3. Rates of sexual aggression perpetration for women were 10.6% at Time 1 (since age 14), 3.5% at Time 2 (since T1), and 3.6% at Time 3 (since T2). For men, the rates were 18.0% at Time 1, 6.2% at Time 2, and 3.8% at Time 3. The gender differences in victimization and perpetration were significant only at T1. CSA predicted higher odds of sexual aggression victimization and perpetration cross-sectionally at T1 and indirectly at T2 and T3 via T1. Gender did not moderate the associations. CONCLUSION: The results confirm previous findings of elevated rates of sexual aggression victimization and perpetration in adolescence and young adulthood in victims of CSA. The implications for understanding and preventing adverse sexuality-related outcomes of CSA are discussed.


Childhood sexual abuse has been linked to an increased vulnerability to sexual revictimization and risk of later sexual aggression perpetration.This longitudinal study based on a large sample of university students in Germany with three data waves covering 23 months shows that sexual abuse in childhood increases the odds of experiencing and engaging in sexual aggression in adolescence and young adulthood.The associations with later sexual aggression victimization and perpetration held for both female and male victims of childhood sexual abuse.


Asunto(s)
Víctimas de Crimen , Delitos Sexuales , Humanos , Masculino , Femenino , Niño , Adolescente , Adulto Joven , Adulto , Estudios Longitudinales , Estudios Transversales , Estudiantes , Agresión
4.
Nucleic Acids Res ; 51(17): 9101-9121, 2023 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-37486771

RESUMEN

Cohesin is a highly conserved, multiprotein complex whose canonical function is to hold sister chromatids together to ensure accurate chromosome segregation. Cohesin association with chromatin relies on the Scc2-Scc4 cohesin loading complex that enables cohesin ring opening and topological entrapment of sister DNAs. To better understand how sister chromatid cohesion is regulated, we performed a proteomic screen in budding yeast that identified the Isw1 chromatin remodeler as a cohesin binding partner. In addition, we found that Isw1 also interacts with Scc2-Scc4. Lack of Isw1 protein, the Ioc3 subunit of ISW1a or Isw1 chromatin remodeling activity resulted in increased accumulation of cohesin at centromeres and pericentromeres, suggesting that ISW1a may promote efficient translocation of cohesin from the centromeric site of loading to neighboring regions. Consistent with the role of ISW1a in the chromatin organization of centromeric regions, Isw1 was found to be recruited to centromeres. In its absence we observed changes in the nucleosomal landscape at centromeres and pericentromeres. Finally, we discovered that upon loss of RSC functionality, ISW1a activity leads to reduced cohesin binding and cohesion defect. Taken together, our results support the notion of a key role of chromatin remodelers in the regulation of cohesin distribution on chromosomes.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Centrómero/metabolismo , Cromátides/genética , Cromatina/genética , Cromatina/metabolismo , Proteómica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Cohesinas
5.
Nutrients ; 15(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37432225

RESUMEN

Gastrointestinal (GI) failure can be both a cause of sepsis and a consequence of the systemic pro-inflammatory response in sepsis. Changes in biomarkers of enterocyte damage, citrulline and I-FABP (intestinal fatty acid binding protein), may indicate altered intestinal permeability and damage. The study group consisted of patients with sepsis (N = 28) and septic shock (N = 30); the control group included patients without infection (N = 10). Blood samples were collected for citrulline and I-FABP and a 4-point AGI score (acute GI injury score) was calculated to monitor GI function on days 1, 3, 5, 7, and 10. Citrulline concentrations in the study group were lower than in the control. Lower values were also noted in septic patients with shock when compared to the non-shock group throughout the study period. I-FABP was higher in the septic shock group than in the sepsis group only on days 1 and 3. Citrulline was lower in patients with GI failure (AGI III) when compared to AGI I/II, reaching significance on days 7 (p = 0.034) and 10 (p = 0.015); moreover, a higher AGI score was associated with an increased 28 day mortality (p = 0.038). The results indicate that citrulline measurements, along with the AGI assessment, have clinical potential in monitoring GI function and integrity in sepsis.


Asunto(s)
Enfermedades Intestinales , Sepsis , Choque Séptico , Humanos , Choque Séptico/complicaciones , Citrulina , Sepsis/complicaciones , Proteínas de Unión a Ácidos Grasos
6.
Microorganisms ; 11(4)2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37110249

RESUMEN

Oligocene waters are widely recognized as excellent sources of drinking water. Due to the belief in their good quality, the water from Oligocene intakes in Warsaw, Poland, is made available to users without prior treatment or disinfection. The present study aimed at assessing possible microbiological risks associated with the use of this water. The occurrence of microbiological contaminants in selected intakes was evaluated, in addition to an assessment of possible changes in the microbiological quality of the water under typical storage conditions. The possibility of antibiotic resistance in bacteria isolated from Oligocene water samples was also investigated, as was their sensitivity to selected disinfectants. A small number of bacteria-27.0 ± 60.8 CFU/cm3 and 3.0 ± 3.0 CFU/cm3-were found in Oligocene water intakes for psychrophilic and mesophilic bacteria, respectively. Fecal bacteria were not detected. Bacteria present in Oligocene waters showed the ability to multiply intensively during standard water storage; this was especially true for mesophilic bacteria in water stored at room temperature. In some samples, bacterial counts reached 103-104 CFU/cm3 after 48 h. Almost all bacterial isolates were resistant to the commonly used antibiotics: ampicillin, vancomycin and rifampicin. The bacteria were also insensitive to some disinfectants.

7.
Sex Abuse ; 35(8): 953-980, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36744724

RESUMEN

This pre-registered study evaluated an intervention designed to reduce sexual aggression perpetration and victimization by changing risky scripts for consensual sexual interactions and corresponding risky sexual behavior, and by improving sexual self-esteem, refusal assertiveness, and initiation assertiveness. In a four-wave longitudinal study covering 23 months, 1181 university students in Germany (762 female) were randomly assigned to an intervention and a no-intervention control group. The intervention group completed six weekly modules addressing the targeted theory-based risk and vulnerability factors of sexual aggression perpetration and victimization. Controlling for baseline levels (T1), the intervention group showed less risky sexual scripts one week post-intervention (T2), which predicted less risky sexual behavior nine months later (T3), which predicted lower odds of sexual aggression perpetration and victimization 12 months later (T4). No direct intervention effects on rates of sexual aggression perpetration and victimization at T3 and T4 were found. No indirect intervention effect on sexual aggression was found via sexual self-esteem and sexual assertiveness. However, sexual self-esteem at T2, which was higher in the intervention group, predicted lower odds of sexual aggression victimization at T3 via higher initiation assertiveness at T3. Implications for reducing sexual aggression and conceptualizing risk and vulnerability factors of sexual aggression are discussed.


Asunto(s)
Víctimas de Crimen , Conducta Sexual , Femenino , Humanos , Agresión , Estudios Longitudinales , Estudiantes , Universidades
8.
Ann Bot ; 131(1): 87-108, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34874999

RESUMEN

BACKGROUND AND AIMS: Diploid and polyploid Urochloa (including Brachiaria, Panicum and Megathyrsus species) C4 tropical forage grasses originating from Africa are important for food security and the environment, often being planted in marginal lands worldwide. We aimed to characterize the nature of their genomes, the repetitive DNA and the genome composition of polyploids, leading to a model of the evolutionary pathways within the group including many apomictic species. METHODS: Some 362 forage grass accessions from international germplasm collections were studied, and ploidy was determined using an optimized flow cytometry method. Whole-genome survey sequencing and molecular cytogenetic analysis were used to identify chromosomes and genomes in Urochloa accessions belonging to the 'brizantha' and 'humidicola' agamic complexes and U. maxima. KEY RESULTS: Genome structures are complex and variable, with multiple ploidies and genome compositions within the species, and no clear geographical patterns. Sequence analysis of nine diploid and polyploid accessions enabled identification of abundant genome-specific repetitive DNA motifs. In situ hybridization with a combination of repetitive DNA and genomic DNA probes identified evolutionary divergence and allowed us to discriminate the different genomes present in polyploids. CONCLUSIONS: We suggest a new coherent nomenclature for the genomes present. We develop a model of evolution at the whole-genome level in diploid and polyploid accessions showing processes of grass evolution. We support the retention of narrow species concepts for Urochloa brizantha, U. decumbens and U. ruziziensis, and do not consider diploids and polyploids of single species as cytotypes. The results and model will be valuable in making rational choices of parents for new hybrids, assist in use of the germplasm for breeding and selection of Urochloa with improved sustainability and agronomic potential, and assist in measuring and conserving biodiversity in grasslands.


Asunto(s)
Brachiaria , Poaceae , Poaceae/genética , Brachiaria/genética , Poliploidía , Ploidias , Genómica
9.
J Sex Res ; 60(8): 1206-1221, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36043887

RESUMEN

The current study evaluated an intervention program, designed by the authors and based on the theory of sexual scripts and social learning theory, to reduce empirically established risk and vulnerability factors of sexual aggression. A sample of 1,181 university students in Germany (762 female) were randomly assigned to an intervention and a no-intervention control group. The intervention group completed six modules addressing established antecedents of sexual aggression perpetration and victimization: risky sexual scripts, risky sexual behavior, low sexual self-esteem, low sexual assertiveness, acceptance of sexual coercion, and perceived realism of pornography. After baseline (T1), intervention effects were measured one week after the last module (T2), nine months later (T3), and another 12 months later (T4). The intervention group showed significantly less risky sexual scripts and higher sexual self-esteem at T2, T3, and T4. The intervention indirectly reduced risky sexual behavior at T3 and T4 via less risky sexual scripts at T2 and increased sexual assertiveness at T3 and T4 via higher sexual self-esteem at T2. No intervention effects were found on the acceptance of sexual coercion and pornography realism. The implications of the findings for reducing the prevalence of sexual aggression perpetration and victimization are discussed.


Asunto(s)
Víctimas de Crimen , Estudiantes , Femenino , Humanos , Agresión , Conducta Sexual , Universidades
10.
Front Plant Sci ; 13: 1026364, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36483968

RESUMEN

Structural chromosome rearrangements involving translocations, fusions and fissions lead to evolutionary variation between species and potentially reproductive isolation and variation in gene expression. While the wheats (Triticeae, Poaceae) and oats (Aveneae) all maintain a basic chromosome number of x=7, genomes of oats show frequent intergenomic translocations, in contrast to wheats where these translocations are relatively rare. We aimed to show genome structural diversity and genome relationships in tetraploid, hexaploid and octoploid Avena species and amphiploids, establishing patterns of intergenomic translocations across different oat taxa using fluorescence in situ hybridization (FISH) with four well-characterized repetitive DNA sequences: pAs120, AF226603, Ast-R171 and Ast-T116. In A. agadiriana (2n=4x=28), the selected probes hybridized to all chromosomes indicating that this species originated from one (autotetraploid) or closely related ancestors with the same genomes. Hexaploid amphiploids were confirmed as having the genomic composition AACCDD, while octoploid amphiploids showed three different genome compositions: AACCCCDD, AAAACCDD or AABBCCDD. The A, B, C, and D genomes of oats differ significantly in their involvement in non-centromeric, intercalary translocations. There was a predominance of distal intergenomic translocations from the C- into the D-genome chromosomes. Translocations from A- to C-, or D- to C-genome chromosomes were less frequent, proving that at least some of the translocations in oat polyploids are non-reciprocal. Rare translocations from A- to D-, D- to A- and C- to B-genome chromosomes were also visualized. The fundamental research has implications for exploiting genomic biodiversity in oat breeding through introgression from wild species potentially with contrasting chromosomal structures and hence deleterious segmental duplications or large deletions in amphiploid parental lines.

11.
Front Plant Sci ; 13: 952968, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186069

RESUMEN

Cenchrus ciliaris is an apomictic, allotetraploid pasture grass widely distributed in the tropical and subtropical regions of Africa and Asia. In this study, we aimed to investigate the genomic organization and characterize some of the repetitive DNA sequences in this species. Due to the apomictic propagation, various aneuploid genotypes are found, and here, we analyzed a 2n = 4x + 3 = 39 accession. The physical mapping of Ty1-copia and Ty3-gypsy retroelements through fluorescence in situ hybridization with a global assessment of 5-methylcytosine DNA methylation through immunostaining revealed the genome-wide distribution pattern of retroelements and their association with DNA methylation. Approximately one-third of Ty1-copia sites overlapped or spanned centromeric DAPI-positive heterochromatin, while the centromeric regions and arms of some chromosomes were labeled with Ty3-gypsy. Most of the retroelement sites overlapped with 5-methylcytosine signals, except for some Ty3-gypsy on the arms of chromosomes, which did not overlap with anti-5-mC signals. Universal retrotransposon probes did not distinguish genomes of C. ciliaris showing signals in pericentromeric regions of all 39 chromosomes, unlike highly abundant repetitive DNA motifs found in survey genome sequences of C. ciliaris using graph-based clustering. The probes developed from RepeatExplorer clusters gave strong in situ hybridization signals, mostly in pericentromeric regions of about half of the chromosomes, and we suggested that they differentiate the two ancestral genomes in the allotetraploid C. ciliaris, likely having different repeat sequence variants amplified before the genomes came together in the tetraploid.

12.
Aggress Behav ; 48(6): 573-582, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35766528

RESUMEN

From the beginning of systematic research on sexual victimization, it has been recognized that a substantial proportion of women report nonconsensual sexual experiences meeting the defining criteria of rape in response to behaviorally specific items, but do not acknowledge their experience as rape in response to broad questions about whether they have ever been raped. Recent studies suggest that rates of unacknowledged rape may be as high or even higher among men than among women. This study examined rates of unacknowledged female and male victims of rape and sexual assault by comparing responses to behaviorally specific items of the Sexual Aggression and Victimization Scale (SAV-S) with responses to broad questions using the labels of sexual assault and rape (SARA) in 593 participants (303 women) in Germany. As predicted, more women and men were classified as rape victims based on behaviorally specific items than on the basis of the broad rape item. The rates of unacknowledged rape were about 60% for women and 75% for men. The gender difference was not significant. Against our prediction, no significant differences in acknowledgement of sexual assault were found in relation to coercive strategy and victim-perpetrator relationship. Few cases of rape and sexual assault identified by the SARA items were missed by the behaviorally specific questions. The implications for establishing prevalence rates of rape and sexual assault and for comparing victims and nonvictims in terms of vulnerability factors and outcomes of sexual victimization are discussed.


Asunto(s)
Acoso Escolar , Víctimas de Crimen , Violación , Delitos Sexuales , Femenino , Humanos , Masculino , Conducta Sexual
13.
J Interpers Violence ; 37(3-4): NP1377-NP1400, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-32506992

RESUMEN

Sexual aggression is a problem among college students worldwide, and a growing body of research has identified variables associated with an increased risk of victimization and perpetration. Among these, sexuality-related cognitions, such as sexual scripts, sexual self-esteem, perceived realism of pornography, and acceptance of sexual coercion, play a major role. The current experimental study aimed to show that these cognitive risk factors of sexual aggression victimization and perpetration are amenable to change, which is a critical condition for evidence-based intervention efforts. College students in Germany (N = 324) were randomly assigned to one of three groups: a treatment group designed to change participants' sexual scripts for consensual sex with regard to the role of alcohol consumption, casual sex, and ambiguous communication of sexual intentions as risk factors for sexual aggression (EG1), a treatment group designed to promote sexual self-esteem, challenge the perceived realism of pornography, and reduce the acceptance of sexual coercion (EG2), and a non-treatment control group (CG). Baseline (T1), post-experimental (T2), and follow-up (T3) measures were taken across an eight-week period. Sexual scripts contained fewer risk factors for sexual aggression in EG1 than in EG2 and CG at T3. Sexual self-esteem was enhanced in EG2 at T2 relative to the other two groups. Acceptance of sexual coercion was lower in EG2 than in EG1 and CG at T2 and T3. No effect was found for perceived realism of pornography. The findings are discussed in terms of targeting cognitive risk factors as a basis for intervention programs.


Asunto(s)
Coerción , Literatura Erótica , Agresión , Cognición , Humanos , Percepción , Factores de Riesgo , Conducta Sexual , Universidades
14.
J Interpers Violence ; 37(19-20): NP17784-NP17806, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34279156

RESUMEN

Measures designed to collect prevalence reports of sexual victimization need to be robust against variations of question context to yield valid findings. Previous research has examined variations in the order in which questions about unwanted sexual acts and questions about coercive tactics are presented. The current study examined potential effects of the order in which coercive tactics are presented on self-reported prevalence rates of sexual victimization. The following two versions of the Sexual Aggression and Victimization Scale (SAV-S), a validated measure for studying sexual aggression victimization and perpetration in college students, were used: (a) the standard version in which the physical-force items were presented first and the items referring to the use of verbal pressure were presented last, and (b) a reversed order in which the verbal-pressure items were presented first and the physical-force items were presented last. Items referring to the exploitation of the victim's inability to resist were placed in the middle in both versions. In a sample of 856 participants from Germany (475 female, 381 male, mean age of 24 years), most of whom were university students, 80.4% of women and 55.3% of men reported at least one experience of sexual victimization since the age of 14. No order effects on overall victimization rates were found. For both genders, the victimization rate through verbal pressure was higher when this tactic was presented first. Victimization rates through the threat or use of force were higher in the force-first than in the force-last condition for women, but could not be tested for men due to small cell sizes. No order effects were found for both men and women on reports of victimization through exploiting the inability to resist. The implications of the results for the reliable measurement of sexual aggression are discussed.


Asunto(s)
Acoso Escolar , Víctimas de Crimen , Adulto , Agresión , Coerción , Femenino , Humanos , Masculino , Conducta Sexual , Estudiantes , Adulto Joven
16.
New Dir Child Adolesc Dev ; 2021(178): 11-37, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34724332

RESUMEN

Violence in adolescent relationships is a common problem with numerous negative short- and long-term consequences. Because most of the evidence on teen dating violence (TDV) synthesized in reviews comes from North American studies, this review aimed to compile evidence on prevalence rates of TDV based on studies identified for Europe only. Specifically, we considered different forms of TDV victimization and perpetration, gender differences, and its measurement. A systematic literature search of the most popular databases Ebsco and PubMed yielded a total of N = 34 studies, with most of the studies identified for Spain, and only a few studies in other European countries. In sum, the results revealed a great variability in prevalence rates across and within the European countries, a common pattern of gender differences, and a wide range of applied measures, corresponding with the evidence from the North American studies. Implications for future research and policy were discussed.


Asunto(s)
Conducta del Adolescente , Víctimas de Crimen , Violencia de Pareja , Adolescente , Humanos , Prevalencia , Violencia
17.
New Dir Child Adolesc Dev ; 2021(178): 59-77, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34664777

RESUMEN

Although teen dating violence (TDV) is internationally recognized as a serious threat to adolescents' health and well-being, almost no data is available for Slovenian youth. Hence, the purpose of this study was to examine the prevalence and predictors of TDV among Slovenian adolescents for the first time. Using data from the SPMAD study (Study of Parental Monitoring and Adolescent Delinquency), 330 high school students were asked about physical TDV victimization and perpetration as well as about their dating history, relationship conflicts, peers' antisocial behavior, and informal social control by family and school. A substantial number of female and male adolescents reported victimization (16.7% of female and 12.7% of male respondents) and perpetration (21.1% of female and 6.0% of male respondents). Furthermore, the results revealed that lower age at the first relationship, relationship conflicts, and school informal social control were associated with victimization, whereas being female, relationship conflicts, having antisocial peers, and family informal social control were linked to perpetration. Implications of the study findings were discussed.


Asunto(s)
Conducta del Adolescente , Violencia de Pareja , Adolescente , Femenino , Humanos , Masculino , Prevalencia , Instituciones Académicas , Eslovenia/epidemiología , Estudiantes
18.
New Dir Child Adolesc Dev ; 2021(178): 115-131, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34480520

RESUMEN

Although dating violence poses a serious threat to adolescents' health and well-being around the globe, little evidence is available for Europe in general and Switzerland in particular. Also, evidence on the role of cognitive predictors related to a more general justification of aggressive behavior and gender-based violence is lacking. Therefore, this two-wave longitudinal study conducted with Swiss adolescents (N = 646) examined moral neutralization of aggression and justification of violence against women as predictors of physical dating violence perpetration and monitoring. As expected, higher moral neutralization of aggression predicted a higher likelihood of perpetrating physical dating violence and monitoring among both female and male adolescents. Justification of violence against women was positively associated with physical dating violence perpetration among males, but negatively among females. Also, a negative relationship was found with monitoring among females. The role of gender and implications of these findings for research, practice, and policy are discussed.


Asunto(s)
Conducta del Adolescente , Víctimas de Crimen , Violencia de Pareja , Adolescente , Agresión , Femenino , Humanos , Relaciones Interpersonales , Estudios Longitudinales , Masculino , Principios Morales , Suiza , Violencia
19.
Genes (Basel) ; 12(7)2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201593

RESUMEN

Urochloa (including Brachiaria, Megathyrus and some Panicum) tropical grasses are native to Africa and are now, after selection and breeding, planted worldwide, particularly in South America, as important forages with huge potential for further sustainable improvement and conservation of grasslands. We aimed to develop an optimized approach to determine ploidy of germplasm collection of this tropical forage grass group using dried leaf material, including approaches to collect, dry and preserve plant samples for flow cytometry analysis. Our methods enable robust identification of ploidy levels (coefficient of variation of G0/G1 peaks, CV, typically <5%). Ploidy of some 348 forage grass accessions (ploidy range from 2x to 9x), from international genetic resource collections, showing variation in basic chromosome numbers and reproduction modes (apomixis and sexual), were determined using our defined standard protocol. Two major Urochloa agamic complexes are used in the current breeding programs at CIAT and EMBRAPA: the 'brizantha' and 'humidicola' agamic complexes are variable, with multiple ploidy levels. Some U. brizantha accessions have odd level of ploidy (5x), and the relative differences in fluorescence values of the peak positions between adjacent cytotypes is reduced, thus more precise examination of this species is required. Ploidy measurement of U. humidicola revealed aneuploidy.


Asunto(s)
Citometría de Flujo , Hojas de la Planta/genética , Ploidias , Poaceae/genética , Genoma de Planta/genética
20.
Arch Sex Behav ; 50(5): 2109-2121, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34195907

RESUMEN

This study examined the prevalence of sexual aggression perpetration and victimization in a sample of 1,172 students (755 female, 417 male) from four universities in Germany. All participants were asked about both victimization by, and perpetration of, sexual aggression since the age of 14 years, using the Sexual Aggression and Victimization Scale (SAV-S). Prevalence rates were established for different coercive strategies, sexual acts, and victim-perpetrator relationships. Both same-sex and opposite-sex victim-perpetrator constellations were examined. The overall victimization rate was 62.1% for women and 37.5% for men. The overall perpetration rate was 17.7% for men and 9.4% for women. Prevalence rates of both victimization and perpetration were higher for participants who had sexual contacts with both opposite-sex and same-sex partners than for participants with exclusively opposite-sex partners. Significant overlap was found between victim and perpetrator status for men and women as well as for participants with only opposite-sex and both opposite-sex and same-sex partners. A disparity between (higher) victimization and (lower) perpetration reports was found for both men and women, suggesting a general underreporting of perpetration rather than a gendered explanation in terms of social desirability or the perception of consent cues. The findings are placed in the international research literature on the prevalence of sexual aggression before and after the #metoo campaign, and their implications for prevention efforts are discussed.


Asunto(s)
Agresión , Víctimas de Crimen , Adolescente , Femenino , Humanos , Masculino , Prevalencia , Estudiantes , Universidades
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