Caracterización de la ictiofauna en la Laguna del Monte, provincia de Buenos Aires

The purpose of this study was to describe as well as to characterize the fish populations living in Del Monte lagoon, which belongs to the Encadenadas del Oeste system in the province of Buenos Aires, Argentina. This research was carried out using trammel nets with meshes of six different sizes at three sampling stations during October 2003. The species captured in the area of study were firstly identified. The specific diversity of each fishing site was subsequently estimated. In addition, sex ratio, size structure, and the relative abundance both in number and weight were also determined for each species. Total capture included 647 individuals, which corresponded to the following six species: mojarra Astyanax eigenmanniorum, dientudo Oligosarcus jenynsii, pejerrey Odontesthes bonariensis, carp Cyprinus carpio, sabalito Cyphocharax voga, and catfish Rhamdia quelen. The specific diversity was very similar at the three sampling stations. The mojarra Astyanax eigenmanniorum evidenced the highest relative abundance in number, it was followed by the dientudo Oligosarcus jenynsii and the pejerrey Odontesthes bonariensis. The highest ichthyomass corresponded to the carp Cyprinus carpio. The entrance of the latter to the Del Monte lagoon was corroborated, the highest number of samples was recorded near the outlet of Guaminí and Malleo-Leufú brooks. A marked decrease in the abundance of the pejerrey Odontesthes bonariensis as well as an increase in the number of the dientudo Oligosarcus jenynsii and the mojarra Astyanax eigenmanniorum were also observed.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

Caracterización de la ictiofauna en la Laguna del Monte, provincia de Buenos Aires

The purpose of this study was to describe as well as to characterize the fish populations living in Del Monte lagoon, which belongs to the Encadenadas del Oeste system in the province of Buenos Aires, Argentina. This research was carried out using trammel nets with meshes of six different sizes at three sampling stations during October 2003. The species captured in the area of study were firstly identified. The specific diversity of each fishing site was subsequently estimated. In addition, sex ratio, size structure, and the relative abundance both in number and weight were also determined for each species. Total capture included 647 individuals, which corresponded to the following six species: mojarra Astyanax eigenmanniorum, dientudo Oligosarcus jenynsii, pejerrey Odontesthes bonariensis, carp Cyprinus carpio, sabalito Cyphocharax voga, and catfish Rhamdia quelen. The specific diversity was very similar at the three sampling stations. The mojarra Astyanax eigenmanniorum evidenced the highest relative abundance in number, it was followed by the dientudo Oligosarcus jenynsii and the pejerrey Odontesthes bonariensis. The highest ichthyomass corresponded to the carp Cyprinus carpio. The entrance of the latter to the Del Monte lagoon was corroborated, the highest number of samples was recorded near the outlet of Guaminí and Malleo-Leufú brooks. A marked decrease in the abundance of the pejerrey Odontesthes bonariensis as well as an increase in the number of the dientudo Oligosarcus jenynsii and the mojarra Astyanax eigenmanniorum were also observed.Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Instituto de Limnología "Dr. Raul A. Ringuelet" (ILPLA

How to survey displaced workers in Switzerland ? Sources of bias and ways around them

Studying career outcomes after job loss is challenging because individually displaced worker form a self-selected group. Indeed, the same factors causing the workers to lose their jobs, such as lack of motivation, may also reduce their re-employment prospects. Using data from plant closures where all workers were displaced irrespective of their individual characteristics offers a way around this selection bias. There is no systematic data collection on workers displaced by plant closure in Switzerland. Accordingly, we conducted our own survey on 1200 manufacturing workers who had lost their job 2 years earlier. The analysis of observational data gives rise to a set of methodological challenges, in particular nonresponse bias. Our survey addressed this issue by mixing data collection modes and repeating contact attempts. In addition, we combined the survey data with data from the public unemployment register to examine the extent of nonresponse bias. Our analysis suggests that some of our adjustments helped to reduce bias. Repeated contact attempts increased the response rate, but did not reduce nonresponse bias. In contrast, using telephone interviews in addition to paper questionnaires helped to substantially improve the participation of typically underrepresented subgroups. However, the survey respondents still differ from nonrespondents in terms of age, education and occupation. Interestingly, these differences have no significant impact on the substantial conclusion about displaced workers' re-employment prospects

Genetics and physiology of cell wall polysaccharides in the model C(4) grass, Setaria viridis spp

Published: 2 October 2015BACKGROUND: Setaria viridis has emerged as a model species for the larger C4 grasses. Here the cellulose synthase (CesA) superfamily has been defined, with an emphasis on the amounts and distribution of (1,3;1,4)-β-glucan, a cell wall polysaccharide that is characteristic of the grasses and is of considerable value for human health. METHODS: Orthologous relationship of the CesA and Poales-specific cellulose synthase-like (Csl) genes among Setaria italica (Si), Sorghum bicolor (Sb), Oryza sativa (Os), Brachypodium distachyon (Bradi) and Hordeum vulgare (Hv) were compared using bioinformatics analysis. Transcription profiling of Csl gene families, which are involved in (1,3;1,4)-β-glucan synthesis, was performed using real-time quantitative PCR (Q-PCR). The amount of (1,3;1,4)-β-glucan was measured using a modified Megazyme assay. The fine structures of the (1,3;1,4)-β-glucan, as denoted by the ratio of cellotriosyl to cellotetraosyl residues (DP3:DP4 ratio) was assessed by chromatography (HPLC and HPAEC-PAD). The distribution and deposition of the MLG was examined using the specific antibody BG-1 and captured using fluorescence and transmission electron microscopy (TEM). RESULTS: The cellulose synthase gene superfamily contains 13 CesA and 35 Csl genes in Setaria. Transcript profiling of CslF, CslH and CslJ gene families across a vegetative tissue series indicated that SvCslF6 transcripts were the most abundant relative to all other Csl transcripts. The amounts of (1,3;1,4)-β-glucan in Setaria vegetative tissues ranged from 0.2% to 2.9% w/w with much smaller amounts in developing grain (0.003% to 0.013% w/w). In general, the amount of (1,3;1,4)-β-glucan was greater in younger than in older tissues. The DP3:DP4 ratios varied between tissue types and across developmental stages, and ranged from 2.4 to 3.0:1. The DP3:DP4 ratios in developing grain ranged from 2.5 to 2.8:1. Micrographs revealing the distribution of (1,3;1,4)-β-glucan in walls of different cell types and the data were consistent with the quantitative (1,3;1,4)-β-glucan assays. CONCLUSION: The characteristics of the cellulose synthase gene superfamily and the accumulation and distribution of (1,3;1,4)-β-glucans in Setaria are similar to those in other C4 grasses, including sorghum. This suggests that Setaria is a suitable model plant for cell wall polysaccharide biology in C4 grasses.Riksfardini A. Ermawar, Helen M. Collins, Caitlin S. Byrt, Marilyn Henderson, Lisa A. O'Donovan, Neil J. Shirley, Julian G. Schwerdt, Jelle Lahnstein, Geoffrey B. Fincher and Rachel A. Burto

The Wage and Non-wage Costs of Displacement: Evidence from Russia

This paper is the first to analyze the costs of job loss in Russia, using unique new data from the Russian Longitudinal Monitoring Survey over the years 2003-2008, including a special supplement on displacement that was initiated by us. We employ fixed effects regression models and propensity score matching techniques in order to establish the causal effect of displacement for displaced individuals. The paper is innovative insofar as we investigate fringe and in-kind benefits and the propensity to have an informal employment relationship as well as a permanent contract as relevant labor market outcomes upon displacement. We also analyze monthly earnings, hourly wages, employment and hours worked, which are traditionally investigated in the literature. Compared to the control group of non-displaced workers (i.e. stayers and quitters), displaced individuals face a significant income loss following displacement, which is mainly due to the reduction in employment and hours worked. This effect is robust to the definition of displacement. The losses seem to be more pronounced and are especially large for older workers with labor market experience and human capital acquired in Soviet times and for workers with primary and secondary education. Workers displaced from state firms experience particularly large relative losses in the short run, while such losses for workers laid off from private firms are more persistent. Turning to the additional non-conventional labor market outcomes, there is a loss in terms of the number of fringe and in-kind benefits for reemployed individuals but not in terms of their value. There is also some evidence of an increased probability of working in informal jobs if displaced. These results point towards the importance of both firm-specific human capital and of obsolete skills obtained under the centrally planned economy as well as to a wider occurrence of job insecurity among displaced workers

Leisure and Housing Consumption after Retirement: New Evidence on the Life-Cycle Hypothesis

We revisit the alleged retirement consumption puzzle. According to the life-cycle theory, foreseeable income reductions such as those around retirement should not affect consumption. However, we first recall that given higher leisure endowments after retirement, the theory does predict a fall of total market consumption expenditures. In order not to mistake this predicted drop for a puzzle we focus on housing consumption which can be plausibly regarded as complementary to leisure, and we control for the leisure change in our empirical specifications, using micro data for Germany (SOEP), where housing expenditures are observable as rents for the majority (60%), as well as dwelling relocations. We still find significant negative impacts of the retirement status on housing consumption, which is hard to reconcile with the life-cycle theory. For retirees we also find significant effects of the income reduction at retirement on housing. However, the effects are small in quantitative terms, given the lock-in nature of past housing decisions

The diet of the black widow spider Latrodectus mirabilis (Theridiidae) in two cereal crops of central Argentina

The spider Latrodectus mirabilis (Holmberg, 1876) is commonly found in cereals crops of central Argentina. We studied its diet composition at the field and capture rate on leaf-cutting ants based on laboratory experiments. This study comprises the first approach that documents the diet of L. mirabilis in wheat and oat fields of central Argentina. We identified 1,004 prey items collected from its webs during the last phenological stages of both cereal crops. The prey composition was variable but the spiders prey mainly on ants (Formicidae, Hymenoptera), who represented more than 86% of the total. Meanwhile, in the capture rate experiences we registered a high proportion of ants captured by spiders at the beginning of experiences, capturing the half of the ants from total in the first four hours. Summarizing, we reported a polyphagous diet of this spider species in wheat and oat fields. Ants were the most important prey item of this spider, as found in other Latrodectus spiders around the world

A Rapid and Simple Procedure for the Establishment of Human Normal and Cancer Renal Primary Cell Cultures from Surgical Specimens

The kidney is a target organ for the toxicity of several xenobiotics and is also highly susceptible to the development of malignant tumors. In both cases, in vitro studies provide insight to cellular damage, and represent adequate models to study either the mechanisms underlying the toxic effects of several nephrotoxicants or therapeutic approaches in renal cancer. The development of efficient methods for the establishment of human normal and tumor renal cell models is hence crucial. In this study, a technically simple and rapid protocol for the isolation and culture of human proximal tubular epithelial cells and human renal tumor cells from surgical specimens is presented. Tumor and normal tissues were processed by using the same methodology, based on mechanical disaggregation of tissue followed by enzymatic digestion and cell purification by sequential sieving. The overall procedure takes roughly one hour. The resulting cell preparations have excellent viabilities and yield. Establishment of primary cultures from all specimens was achieved successfully. The origin of primary cultured cells was established through morphological evaluation. Normal cells purity was confirmed by immunofluorescent staining and reverse transcription-polymerase chain reaction analysis for expression of specific markers