Long-term development in a Baltic fish community exposed to bleached pulp mill effluent

Observations near a Swedish pulp mill at the Bothnian Sea during 1982-1992 revealed low fish abundance and a disturbed community structure. The presence of endocrine disrupting or toxic substances in effluent water was indicated by biomarker responses, impaired reproduction and stimulated growth in perch (Perca fluviatilis). In 1992 the bleaching process was altered and a secondary treatment system was installed, improving the quality and decreasing the amount of effluent. This paper presents the results of follow-up studies during 1995-1998 with the objective to analyse any recovery of the fish community due to changes in mill operations. Although abundance and diversity of the fish community did recover, an effect of enrichment, indicated by high catches of cyprinids, was still visible in the vicinity of the mill outlet. Sexual maturation was delayed, gonad development was retarded, average growth rate was faster, and the condition factor was higher in perch caught in the vicinity of the effluent outlet, than in perch captured elsewhere. It is concluded that substances inhibiting reproduction and causing growth disturbance were still present in the effluents in effective concentrations.     

From analytic inversion to contemporary IMRT optimization: Radiation therapy planning revisited from a mathematical perspective

In this paper we look at the development of radiation therapy treatment planning from a mathematical point of view. Historically, planning for Intensity-Modulated Radiation Therapy (IMRT) has been considered as an inverse problem. We discuss first the two fundamental approaches that have been investigated to solve this inverse problem: Continuous analytic inversion techniques on one hand, and fully-discretized algebraic methods on the other hand. In the second part of the paper, we review another fundamental question which has been subject to debate from the beginning of IMRT until the present day: The rotation therapy approach versus fixed angle IMRT. This builds a bridge from historic work on IMRT planning to contemporary research in the context of Intensity-Modulated Arc Therapy (IMAT).     

Morphology of the first-instar nymph and adult female of Kermes echinatus Balachowsky,with a comparison to K. vermilio Planchon (Hemiptera,?Coccoidea,?Kermesidae)

Thefirst-instar nymph and the adult female of Kermes echinatus Balachowsky (Hemiptera, Coccoidea, Kermesidae) are described and illustrated. This species is compared with Kermes vermilio Planchon, a morphologically similar species known in the Palaeractic region.     

Function of Cancer Associated Genes Revealed by Modern Univariate and Multivariate Association Tests

Copy number variation (CNV) plays a role in pathogenesis of many human diseases, especially cancer. Several whole genome CNV association studies have been performed for the purpose of identifying cancer associated CNVs. Here we undertook a novel approach to whole genome CNV analysis, with the goal being identification of associations between CNV of different genes (CNV-CNV) across 60 human cancer cell lines. We hypothesize that these associations point to the roles of the associated genes in cancer, and can be indicators of their position in gene networks of cancer-driving processes. Recent studies show that gene associations are often non-linear and non-monotone. In order to obtain a more complete picture of all CNV associations, we performed omnibus univariate analysis by utilizing dCov, MIC, and HHG association tests, which are capable of detecting any type of association, including non-monotone relationships. For comparison we used Spearman and Pearson association tests, which detect only linear or monotone relationships. Application of dCov, MIC and HHG tests resulted in identification of twice as many associations compared to those found by Spearman and Pearson alone. Interestingly, most of the new associations were detected by the HHG test. Next, we utilized dCov''s and HHG''s ability to perform multivariate analysis. We tested for association between genes of unknown function and known cancer-related pathways. Our results indicate that multivariate analysis is much more effective than univariate analysis for the purpose of ascribing biological roles to genes of unknown function. We conclude that a combination of multivariate and univariate omnibus association tests can reveal significant information about gene networks of disease-driving processes. These methods can be applied to any large gene or pathway dataset, allowing more comprehensive analysis of biological processes.     

Impact clinique de la technique du temps-de-vol en TEP

Time-of-flight PET improves the image quality by increasing signal-to-noise ratio. This improvement increases with time resolution. Recent data confirm the clinical benefits of time-of-flight PET. The signal-to-noise gain has led to a dose reduction, shorter scans, better image quality especially in patients with high Body Mass Index, and improvement in detection of smaller lesions.     

Zoogeography of Intertidal Communities in the West Indian Ocean as Determined by Ocean Circulation Systems: Patterns from the Tetraclita Barnacles

The Indian Ocean is the least known ocean in the world with the biogeography of marine species in the West Indian Ocean (WIO) understudied. The hydrography of WIO is characterized by four distinct oceanographic systems and there were few glacial refugia formations in the WIO during the Pleistocene. We used the widely distributed intertidal barnacle Tetraclita to test the hypothesis that the distribution and connectivity of intertidal animals in the WIO are determined by the major oceanographic regime but less influenced by historical events such as Pleistocene glaciations. Tetraclita were studied from 32 locations in the WIO. The diversity and distribution of Tetraclita species in the Indian Ocean were examined based on morphological examination and sequence divergence of two mitochondrial genes (12S rDNA and COI) and one nuclear gene (histone 3, H3). Divergence in DNA sequences revealed the presence of seven evolutionarily significant units (ESUs) of Tetraclita in WIO, with most of them recognized as valid species. The distribution of these ESUs is closely tied to the major oceanographic circulation systems. T. rufotincta is distributed in the Monsoonal Gyre. T. ehsani is present in the Gulf of Oman and NW India. Tetraclita sp. nov. is associated with the Hydrochemical Front at 10°S latitude. T. reni is confined to southern Madagascan and Mauritian waters, influenced by the West Wind Drift. The endemic T. achituvi is restricted to the Red Sea. Tetraclita serrata consists of two ESUs (based on mtDNA analysis) along the east to west coast of South Africa. The two ESUs could not be distinguished from morphological analysis and nuclear H3 sequences. Our results support that intertidal species in the West Indian Ocean are associated with each of the major oceanographic circulation systems which determine gene flow. Geographical distribution is, however, less influenced by the geological history of the region.     

Metaphor Identification in Large Texts Corpora

Identifying metaphorical language-use (e.g., sweet child) is one of the challenges facing natural language processing. This paper describes three novel algorithms for automatic metaphor identification. The algorithms are variations of the same core algorithm. We evaluate the algorithms on two corpora of Reuters and the New York Times articles. The paper presents the most comprehensive study of metaphor identification in terms of scope of metaphorical phrases and annotated corpora size. Algorithms’ performance in identifying linguistic phrases as metaphorical or literal has been compared to human judgment. Overall, the algorithms outperform the state-of-the-art algorithm with 71% precision and 27% averaged improvement in prediction over the base-rate of metaphors in the corpus.     

Effects of sensory deprivation on the development of asymmetrical synapses in mouse barrels

Alterations in the numerical density and structure of asymmetrical synapses were examined in thin sections through barrel D4 in six CD/1 mice, including three controls and three sensory deprived animals. Sensory deprivation was effected by once daily trimming of all large mystacial vibrissae on the contralateral side of the snout from P0. The mice were perfuse-fixed at P20, several days following the termination of rapid synaptic growth during barrel development (White et al. , Somatosens Mot Res 14 : 34-55, 1997). Cerebral hemispheres contralateral to the deprived side were osmicated, sectioned at 40 mum and embedded in plastic for thin sectioning. Sterio's ( J Microsc 134 : 127-136, 1984) procedure combined with serial thin section analysis (Braendgaard and Gundersen, J Neurosci Meth 18 : 39-78, 1986), was applied blindly to systematic random samples of neuropil in barrel hollows and septa. No significant difference in the numerical density, estimated total number, or in the proportion of perforated postsynaptic densities was observed. However, a significant decrease in the diameters of asymmetrical postsynaptic densities was observed in hollow (P < 0.05) and septal (P < 0.05) neuropil of deprived animals. These results demonstrate a significant morphological alteration in asymmetrical synapses of a type consistent with a reduction in synaptic activity consequent to sensory deprivation.     

Nerve growth factor induces rapid redistribution of F-actin in PC12 cells

Nerve growth factor (NGF) induces the redistribution of F-actin in rat pheochromocytoma PC12 cells within 2-10 min, whereas epidermal growth factor (EGF) has no effect on microfilament organization. This redistribution of F-actin in PC12 cells is not protein synthesis dependent, but can be blocked by methyltransferase inhibitors.     

B lymphocyte inhibition of anti-tumor response depends on expansion of Treg but is independent of B-cell IL-10 secretion

The mechanisms by which B lymphocytes inhibit anti-tumor immunity remain poorly understood. Murine EMT-6 mammary tumors grow readily in immune competent mice (BALB/c), but poorly in B-cell-deficient μ^?/? BALB/c mice (BCDM). T regulatory cell (Treg) expansion and function were impaired in BCDM compared with BALB/c. In this study, we compared tumor growth, Treg cell proliferation, tumor lymphocyte infiltration and cytolytic T cell activity in BALB/c, BCDM and BCDM partially reconstituted with B cells by adoptive transfer (BCDM+B). Partial reconstitution of BCDM with adoptively transferred B cells restored EMT-6 tumor growth, which was independent of IL-10 secretion by B cells. Instead, high frequencies of intratumoral B cells were associated with increased recruitment and proliferation of Treg cells within the tumor microenvironment. The B-cell-dependent accumulation of Treg within the tumor microenvironment was associated with reduced tumor infiltration by CD49+ NK and CD8+ T cells and reduced cytotoxic T cell activity against EMT-6 targets. Our studies indicate that tumor-dependent immunosuppression of T-cell-mediated anti-tumor immunity is coordinated within the tumor microenvironment by B-cell-dependent cross talk with Treg cells, which does not require production of IL-10 by B cells.