Adolescents' involvement in cyber bullying and perceptions of school: the importance of perceived peer acceptance for female adolescents

Young people are spending increasing amounts of time using digital technology and, as such, are at great risk of being involved in cyber bullying as a victim, bully, or bully/victim. Despite cyber bullying typically occurring outside the school environment, the impact of being involved in cyber bullying is likely to spill over to school. Fully 285 11- to 15-year-olds (125 male and 160 female, M age = 12.19 years, SD = 1.03) completed measures of cyber bullying involvement, self-esteem, trust, perceived peer acceptance, and perceptions of the value of learning and the importance of school. For young women, involvement in cyber bullying as a victim, bully, or bully/victim negatively predicted perceptions of learning and school, and perceived peer acceptance mediated this relationship. The results indicated that involvement in cyber bullying negatively predicted perceived peer acceptance which, in turn, positively predicted perceptions of learning and school. For young men, fulfilling the bully/victim role negatively predicted perceptions of learning and school. Consequently, for young women in particular, involvement in cyber bullying spills over to impact perceptions of learning. The findings of the current study highlight how stressors external to the school environment can adversely impact young women's perceptions of school and also have implications for the development of interventions designed to ameliorate the effects of cyber bullying

The Psychological impact of bullying on victims, bullies and student defenders

It is widely held that bullying is a group process involving bullies, victims, students who reinforce the bully, students who defend the victim, and students who are not involved in the bullying scenario. While there is a wealth of research investigating the psychological impact of bullying on victims, research findings related to bullies are inconsistent. Research with witnesses found students who witness bullying are more depressed than those who do not witness bullying raising questions about the potential impact of bullying on students who intervene. The aim of the present study was to investigate possible relationships between depression and bullying, victimisation, comforting victims and intervening. One thousand two hundred and eighty five (692 female) predominantly White Australian students in grades 7-10 completed a questionnaire measuring frequency of bully, victim and defender behaviour, depression, empathic efficacy, rumination and collective efficacy to stop bullying. Victimisation and comforting the victim of phsyical bullying were associated with depression. The relationship between victimisation and depression was mediated by collective efficacy to stop bullying and rumination, whereas the relationship between comforting the victim of physical bullying and depression was mediated by empathic efficacy and depression rumination.1 page(s

Using gene expression information obtained by quantitative real-time PCR to evaluate Angus bulls divergently selected for feed efficiency

Residual feed intake (RFI) is a measure of feed efficiency in beef cattle. Young Angus bulls from lines of cattle divergently selected for RFI were used in a gene expression profiling study of the liver. Quantitative real-time PCR (qPCR) assay was used to quantify the differentially expressed genes and the information was used to examine the relationships between the genes and RFI and to classify the bulls into their respective RFI group. Gene expression of 21 genes in liver biopsies from 22 low RFI and 22 high RFI bulls were measured by qPCR. Gene expressions of 14 of the 21 genes were significantly correlated with RFI. The expression of the genes was used in a principal component analysis from which five components were extracted. The five principal components explained 70% of the variation in the dependency structure. The first component was highly correlated (correlation coefficient of 0.69) with RFI. The genes of the glutathione S-transferase Mu family (GSTM1, GSTM2, GSTM4), protocadherin 19 (PCDH19), ATP-binding cassette transporter C4 (ABCC4) and superoxide dismutase 3 (SOD3) are in the xenobiotic pathway and were the key factors in the first principal component. This highlights the important relationship between this pathway and variation in RFI. The second and third principal components were also correlated with RFI, with correlation coefficients of -0.28 and -0.20, respectively. Two of the four important genes of the second principal component work coordinately in the signalling pathways that inhibit the insulin-stimulated insulin receptor and regulate energy metabolism. This is consistent with the observation that a positive genetic correlation exists between RFI and fatness. The important genes in the third principal component are related to the extracellular matrix activity, with low RFI bulls showing high extracellular matrix activity

Use of garden organic compost in a long-term vegetable field trial : biological soil health

Alternative management practices need to be developed to improve the sustainability of intensive vegetable production in peri-urban areas. A field trial was established in 2005 at Camden, near Sydney, Australia to evaluate the effect of garden organic compost on vegetable production and soil quality relative to conventional practice and under low and high soil P status. The trial comprised seven treatments; compost (garden organic), conventional practice (fertiliser and poultry manure) and a mixture of compost and inorganic fertiliser, all replicated at high and low soil P, plus a nil control. Compost was applied once at the beginning of the trial and again before the 6 th crop (125 dry t/ha/application). Results are reported for 7 consecutive vegetable crops: broccoli, eggplant, cabbage, capsicum, leek, capsicum and broccoli. Production and crop quality parameters were recorded. Soil samples were collected and chemical, physical and biological properties analysed at the time of planting all crops and prior to harvest for crops 4 to 6. Soil biological indicators measured include basal respiration, microbial biomass carbon, hydrolysis of fluorescein diacetate (FDA) and fungal DNA. Compost application significantly increased soil respiration in the first crop but the benefit was diminished in subsequent crops. The response was more pronounced in the crop soils following the second compost application with respiration, biomass and FDA higher in the compost treatments. Preliminary DNA analysis of soil samples collected in the second capsicum crop found a greater diversity of fungal organisms in the low P compost treatment. Future work will look at expanding the assessment of soil biological indicators and the potential for pathogen suppression.10 page(s

Changes in soil quality over five consecutive vegetable crops following the application of garden organics compost

A field experiment was established near Camden in south west Sydney, Australia in 2005 to evaluate the effect of garden organics compost on vegetable production and soil quality relative to conventional practice. Treatments were full compost (125 dry t/ha), half compost (62.5 dry t/ha supplemented by inorganic fertilisers), conventional farmers practice (mixture of poultry manure and inorganic fertilisers), and control (nil inputs) in a fully randomised and replicated experiment with 4 blocks. It was evident at the start of the experiment (i.e., crop 1), that compared to the conventional farmers practice treatment, the full compost treatment (120 dry t/ha) had produced significantly (P0.25 mm. This study demonstrated that a 125 dry t/ha compost application rejuvenated soil quality and maintained many soil quality benefits over the five crops, despite the high tillage associated with rotary hoe use in this system.16 page(s