164 research outputs found
Taxonomic diversity of benthic macroinvertebrates along the Oum Er Rbia River (Morocco): implications for water quality bio-monitoring using indicator species
The macroinvertebrates of the Oum Er Rbia River were studied from samples collected seasonally from September 2015 to September 2016 at 10 sampling sites. The macroinvertebrates found during the sampling period were distributed into twelve orders. The most abundant order was diptera, having 9618 individuals, followed by the order Ephemeroptera with 2985 individuals. Coleoptera, odonates and crustaceans represent only a small fraction of the total fauna. Hydropsyche, Chironomidae sp. and Simuliidae are numerically more inventoried. The composition and distribution of the species were directly or indirectly affected by the physicochemical variables and the quality of the habitat. Correspondence analysis results showed that habitat quality and quality of water represented species distribution patterns and species can be used as indicators to assess the quality of the Oum Er Rbia River system. Habitat management along the Oum Er Rbia river should be aimed at preserving native species, especially during the summer, when the biotope requirements are optimal. The results obtained in this study showed an alarming situation of the water quality of the Oum Er Rbia River and particularly in downstream segment. To solve this problem, we recommend the development of the wastewater discharge of Khenifra and Kasba Tadla and the purification of wastewater before it is discharged into the river
The endogenous and reactive depression subtypes revisited: integrative animal and human studies implicate multiple distinct molecular mechanisms underlying major depressive disorder
Traditional diagnoses of major depressive disorder (MDD) suggested that the presence or absence of stress prior to onset results in either 'reactive' or 'endogenous' subtypes of the disorder, respectively. Several lines of research suggest that the biological underpinnings of 'reactive' or 'endogenous' subtypes may also differ, resulting in differential response to treatment. We investigated this hypothesis by comparing the gene-expression profiles of three animal models of 'reactive' and 'endogenous' depression. We then translated these findings to clinical samples using a human post-mortem mRNA study
Energy Dependence of Nuclear Transparency in C(p,2p) Scattering
The transparency of carbon for (p,2p) quasi-elastic events was measured at
beam energies ranging from 6 to 14.5 GeV at 90 degrees c.m. The four momentum
transfer squared q*q ranged from 4.8 to 16.9 (GeV/c)**2. We present the
observed energy dependence of the ratio of the carbon to hydrogen cross
sections. We also apply a model for the nuclear momentum distribution of carbon
to normalize this transparency ratio. We find a sharp rise in transparency as
the beam energy is increased to 9 GeV and a reduction to approximately the
Glauber level at higher energies.Comment: 4 pages, 2figures, submitted to PR
Pervasive and opposing effects of Unpredictable Chronic Mild Stress (UCMS) on hippocampal gene expression in BALB/cJ and C57BL/6J mouse strains
Background: BALB/cJ is a strain susceptible to stress and extremely susceptible to a defective hedonic impact in response to chronic stressors. The strain offers much promise as an animal model for the study of stress related disorders. We present a comparative hippocampal gene expression study on the effects of unpredictable chronic mild stress on BALB/cJ and C57BL/6J mice. Affymetrix MOE 430 was used to measure hippocampal gene expression from 16 animals of two different strains (BALB/cJ and C57BL/6J) of both sexes and subjected to either unpredictable chronic mild stress (UCMS) or no stress. Differences were statistically evaluated through supervised and unsupervised linear modelling and using Weighted Gene Coexpression Network Analysis (WGCNA). In order to gain further understanding into mechanisms related to stress response, we cross-validated our results with a parallel study from the GENDEP project using WGCNA in a meta-analysis design. Results: The effects of UCMS are visible through Principal Component Analysis which highlights the stress sensitivity of the BALB/cJ strain. A number of genes and gene networks related to stress response were uncovered including the Creb1 gene. WGCNA and pathway analysis revealed a gene network centered on Nfkb1. Results from the meta-analysis revealed a highly significant gene pathway centred on the Ubiquitin C (Ubc) gene. All pathways uncovered are associated with inflammation and immune response. Conclusions: The study investigated the molecular mechanisms underlying the response to adverse environment in an animal model using a GxE design. Stress-related differences were visible at the genomic level through PCA analysis highlighting the high sensitivity of BALB/cJ animals to environmental stressors. Several candidate genes and gene networks reported are associated with inflammation and neurogenesis and could serve to inform candidate gene selection in human studies and provide additional insight into the pathology of Major Depressive Disorder
Visualization of flow past a marine turbine: the information-assisted search for sustainable energy
Discovery of the molecular mechanisms of the novel chalcone-based Magnaporthe oryzae inhibitor C1 using transcriptomic profiling and co-expression network analysis
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