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Individual Vs. (individual + vs)

Distribution by Scientific Domains

Life Sciences	75%

Selected Abstracts

Responses of dryland soil respiration and soil carbon pool size to abrupt vs. gradual and individual vs. combined changes in soil temperature, precipitation, and atmospheric [CO2]: a simulation analysis

GLOBAL CHANGE BIOLOGY, Issue 9 2009
WEIJUN SHEN
Abstract With the large extent and great amount of soil carbon (C) storage, drylands play an important role in terrestrial C balance and feedbacks to climate change. Yet, how dryland soils respond to gradual and concomitant changes in multiple global change drivers [e.g., temperature (Ts), precipitation (Ppt), and atmospheric [CO2] (CO2)] has rarely been studied. We used a process-based ecosystem model patch arid land simulator to simulate dryland soil respiration (Rs) and C pool size (Cs) changes to abrupt vs. gradual and single vs. combined alterations in Ts, Ppt and CO2 at multiple treatment levels. Results showed that abrupt perturbations generally resulted in larger Rs and had longer differentiated impacts than did gradual perturbations. Rs was stimulated by increases in Ts, Ppt, and CO2 in a nonlinear fashion (e.g., parabolically or asymptotically) but suppressed by Ppt reduction. Warming mainly stimulated heterotrophic Rs (i.e., Rh) whereas Ppt and CO2 influenced autotrophic Rs (i.e., Ra). The combined effects of warming, Ppt, and CO2 were nonadditive of primary single-factor effects as a result of substantial interactions among these factors. Warming amplified the effects of both Ppt addition and CO2 elevation whereas Ppt addition and CO2 elevation counteracted with each other. Precipitation reduction either magnified or suppressed warming and CO2 effects, depending on the magnitude of factor's alteration and the components of Rs (Ra or Rh) being examined. Overall, Ppt had dominant influence on dryland Rs and Cs over Ts and CO2. Increasing Ppt individually or in combination with Ts and CO2 benefited soil C sequestration. We therefore suggested that global change experimental studies for dryland ecosystems should focus more on the effects of precipitation regime changes and the combined effects of Ppt with other global change factors (e.g., Ts, CO2, and N deposition). [source]

Empowerment in social work: an individual vs. a relational perspective

INTERNATIONAL JOURNAL OF SOCIAL WELFARE, Issue 1 2007
Dag Leonardsen
Social workers with only an individualistic understanding of empowerment will easily end up as moralising agents rather than as facilitators for their clients. It is in the complex interaction between a given socio-material situation and the individual capacity to interpret and act that one finds the key to an empowerment worthy of its name. This presupposes two things: that social workers have as a part of their education theoretical knowledge about organisational structures, and that they themselves have been empowered in ways that give them practical competence to act in relation to situations. They need the competence to identify the complexities of interests and power relations in society. The implication of such a recogni-tion should be clear for the education of social workers: the ideology of empowerment has to be contextualised. To discuss this topic the author makes a distinction between an individua-listic and a relational perspective and between social problems conceived of as a ,lack of money' vs. a ,lack of meaning'. [source]

Hepatic transcription response to high-fat treatment in mice: Microarray comparison of individual vs. pooled RNA samples

BIOTECHNOLOGY JOURNAL, Issue 9 2010
Gyeong-Min Do
Abstract Microarray analysis is an important tool in studying gene expression profiles in genomic research. Despite many concerns raised, mRNA samples are often pooled in microarray experiments to reduce the cost and complexity of analysis of transcript profiling. This study reports the results of microarray experiments designed to compare effects of pooling RNA samples and its impact on identifying profiles of mRNA transcripts and differentially expressed genes (DEGs) in the liver of C57BL/6J mice fed normal and high-fat diet. Pearson's correlation coefficient of transcripts between pooled and non-pooled RNA samples was 0.98 to 1.0. The impact of pooled vs. non-pooled RNA samples was also compared by number of transcripts or DEGs. Agreement of significant genes between pooled and non-pooled sets was fairly desirable based on t -test <0.05 and/or signal intensity ,2-fold. Biological process profile and the correlation coefficiency of fold change in the hepatic gene transcripts between pooled and non-pooled samples were also higher than 0.97. This suggests that pooling hepatic RNA samples can reflect the expression pattern of individual samples, and that properly constructed pools can provide nearly identical measures of transcription response to individual RNA sample. [source]

The effect of genetic and environmental variation on metabolic gene expression

MOLECULAR ECOLOGY, Issue 13 2009
CINDA P. SCOTT
Abstract What is the relationship between genetic or environmental variation and the variation in messenger RNA (mRNA) expression? To address this, microarrays were used to examine the effect of genetic and environmental variation on cardiac mRNA expression for metabolic genes in three groups of Fundulus heteroclitus: (i) individuals sampled in the field (field), (ii) field individuals acclimated for 6 months to laboratory conditions (acclimated), or (iii) individuals bred for 10 successive generations in a laboratory environment (G10). The G10 individuals have significantly less genetic variation than individuals obtained in the field and had a significantly lower variation in mRNA expression across all genes in comparison to the other two groups (P = 0.001). When examining the gene specific variation, 22 genes had variation in expression that was significantly different among groups with lower variation in G10 individuals than in acclimated individuals. Additionally, there were fewer genes with significant differences in expression among G10 individuals vs. either acclimated or field individuals: 66 genes have statistically different levels of expression vs. 107 or 97 for acclimated or field groups. Based on the permutation of the data, these differences in the number of genes with significant differences among individuals within a group are unlikely to occur by chance (P < 0.01). Surprisingly, variation in mRNA expression in field individuals is lower than in acclimated individuals. Relative to the variation among individual within a group, few genes have significant differences in expression among groups (seven, 2.3%) and none of these are different between acclimated and field individuals. The results support the concept that genetic variation affects variation in mRNA expression and also suggests that temporal environmental variation associated with estuarine environments does not increase the variation among individuals or add to the differences among groups. [source]