Effect of electrolyte on synergism of anionic-nonionic surfactant mixture

In this study, anionic (Sodium Dodecyl Sulfate) and nonionic (Triton X l00) surfactants mixture (1:1 mass ratio) were evaluated for synergism in Critical Micelle Concentration (CMC) at different ionic strength values. Interaction between the binary surfactant mixture was studied by surface and interfacial tensions. The composition of mixed micelles and the interaction parameter, β evaluated from the CMC data obtained by both surface and interfacial tensions for different systems using Rubingh’ s theory were discussed. It has been shown, that the, micellization behavior of the mixture was improved significantly in presence of salt in particular after equilibration with shale

Protease inhibitors targeting coronavirus and filovirus entry.

In order to gain entry into cells, diverse viruses, including Ebola virus, SARS-coronavirus and the emerging MERS-coronavirus, depend on activation of their envelope glycoproteins by host cell proteases. The respective enzymes are thus excellent targets for antiviral intervention. In cell culture, activation of Ebola virus, as well as SARS- and MERS-coronavirus can be accomplished by the endosomal cysteine proteases, cathepsin L (CTSL) and cathepsin B (CTSB). In addition, SARS- and MERS-coronavirus can use serine proteases localized at the cell surface, for their activation. However, it is currently unclear which protease(s) facilitate viral spread in the infected host. We report here that the cysteine protease inhibitor K11777, ((2S)-N-[(1E,3S)-1-(benzenesulfonyl)-5-phenylpent-1-en-3-yl]-2-{[(E)-4-methylpiperazine-1-carbonyl]amino}-3-phenylpropanamide) and closely-related vinylsulfones act as broad-spectrum antivirals by targeting cathepsin-mediated cell entry. K11777 is already in advanced stages of development for a number of parasitic diseases, such as Chagas disease, and has proven to be safe and effective in a range of animal models. K11777 inhibition of SARS-CoV and Ebola virus entry was observed in the sub-nanomolar range. In order to assess whether cysteine or serine proteases promote viral spread in the host, we compared the antiviral activity of an optimized K11777-derivative with that of camostat, an inhibitor of TMPRSS2 and related serine proteases. Employing a pathogenic animal model of SARS-CoV infection, we demonstrated that viral spread and pathogenesis of SARS-CoV is driven by serine rather than cysteine proteases and can be effectively prevented by camostat. Camostat has been clinically used to treat chronic pancreatitis, and thus represents an exciting potential therapeutic for respiratory coronavirus infections. Our results indicate that camostat, or similar serine protease inhibitors, might be an effective option for treatment of SARS and potentially MERS, while vinyl sulfone-based inhibitors are excellent lead candidates for Ebola virus therapeutics

Family-specific degenerate primer design: a tool to design consensus degenerated oligonucleotides

Designing degenerate PCR primers for templates of unknown nucleotide sequence may be a very difficult task. In this paper, we present a new method to design degenerate primers, implemented in family-specific degenerate primer design (FAS-DPD) computer software, for which the starting point is a multiple alignment of related amino acids or nucleotide sequences. To assess their efficiency, four different genome collections were used, covering a wide range of genomic lengths: Arenavirus ( nucleotides), Baculovirus ( to  bp), Lactobacillus sp. ( to  bp), and Pseudomonas sp. ( to  bp). In each case, FAS-DPD designed primers were tested computationally to measure specificity. Designed primers for Arenavirus and Baculovirus were tested experimentally. The method presented here is useful for designing degenerate primers on collections of related protein sequences, allowing detection of new family members.Fil: Iserte, Javier Alonso. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Stephan, Betina Inés. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Goñi, Sandra Elizabeth. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Borio, Cristina Silvia. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ghiringhelli, Pablo Daniel. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área Virus de Insectos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lozano, Mario Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología. Laboratorio de Ingeniería Genética y Biología Molecular y Celular. Área de Virosis Emergentes y Zoonótica; Argentin

Planktonic rotifers of a saline-lowland river : The Salado River (Argentina)

Seasonal samples of zooplankton were taken during 1997-1999 at fifteen stations in the Salado River basin, and analysed in order to study the rotifer fauna. Spatio-temporal changes in the rotifer plankton composition were examined in the main channel and its tributaries. The majority of species found are tolerant of a wide range of pH, whereas others prefer neutral to alkaline values. The total rotifer plankton density increased downstream from the headwaters to the middle sector of the river. The associated shallow lakes and tributaries were an important source of species. Variations in density and number of species were shown to be associated with conductivity, and species tolerant of high conductivity conditions were especially prevalent (upper 7,000 μS cm-1). Rotifer density was influenced by hydrological conditions, which promoted maximum values during low water periods and in the high water condition promoted the incorporation of species from shallow lakes connected with the river during flood events. The species associations found are related to such water parameters as conductivity and nutrient availability and to the presence of ponds and shallow, waterlogged depressions connected in varying extent to the main channel.Fil: Neschuk, Nancy Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Claps, Maria Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Gabellone, Nestor Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

Addenda and omissions to the catalogue and checklist of the Cerambycidae and Disteniidae (Coleoptera) of the Western hemisphere

The Catalogue (Monne, 1993-1994) and Checklist (Monne and Giesbert, 1995) of the Cerambycidae and Disteniidae of the Western Hemisphere represents a necessary, and valuable tool since recompilation of Blackwelder (1946) was made. Species with references (omissions), and without them (new records) are given for some countries

Measuring beginner reading skills: An empirical evaluation of alternative instruments and their potential use for policymaking and accountability in Peru

Based on analysis of reading performance data from 475 third-graders in Peru, this study makes recommendations on improving reading tests, choice of reading standards, and how to present the results at the school and individual levels. The paper reviews the literature on using reading skills measurement in the early grades to guide policymaking, strengthen accountability, and improve education quality. It uses data generated from the same students using two common approaches to measuring reading skills: an individually-administered oral fluency test, and a group-administered written comprehension test designed by the Ministry of Education for the 2006 universal standard test of second grade reading comprehension. These two approaches have sometimes been presented as competing alternatives, but the paper shows that it is better if they are used together, as complements. Based on psychometric analysis, the paper shows that both the oral and written tests adequately measured studentsâÃÂàreading abilities. The results show that reading fluency and comprehension are correlated: fluent readers are more likely to understand what they read than non-fluent readers. The strength of the fluency-comprehension relationship depends on the level of fluency, the difficulty of the questions, and social characteristics of the school. The paper recommends using improved versions of both tests to evaluate early grade reading skills, as a central element of a system of accountability for results. It proposes a model for reporting test results desgned to highlight the importance of reading standards, mobilize the education community to reach them, track progress, and identify students in need of extra support.academic performance; access to education; access to preschool; access to preschool education; Achievement; achievements; addition; adults; Assessment of Literacy; average score; Basic Skills;

Characterization of producers and quinoa supply chains in the Peruvian regions of Puno and Junin

The present study aims to categorize quinoa producers and examine and compare quinoa supply chains in the Peruvian regions of Puno and Junin. This research was conducted in the provinces of San Roman and El Collao in Puno and Jauja and Huancayo in Junin using surveys of producers selected according to stratified sampling, along with interviews and workshops with traders and agents in the supply chain. Cluster analysis was used to examine the producers’ attributes, the supply chain, and the profit margins of conventional and organic producers. In both regions, most producers were small and medium sized (100% in Puno and 91.6% in Junin). The supply chains in Puno and Junin comprised 24 and 31 channels, respectively. It was found that numerous collectors, formal and informal processors, and exporters mainly linked with organized producers participated in these supply chains and this made trade efficient and coordinated. In contrast, trade among individual producers in the domestic markets through agents in the supply chain was highly disjointed, tending toward high centralization and without added value. It is concluded that quinoa supply is complex, centralized, traditional, and somewhat inefficient since asymmetrical relations were found between agents favoring commercial intermediaries

Experimental Investigation of Interfacial Tension Measurement and Oil Recovery by Carbonated Water Injection : A Case Study Using Core Samples from an Iranian Carbonate Oil Reservoir

The authors would like to gratefully acknowledge and appreciate the Department of Petroleum Engineering, Faculty of Engineering, Marvdasht Islamic Azad University, Marvdasht, 73711-13119, Iran, for the provision of the laboratory facilities necessary for completing this work.Peer reviewedPostprin

Proposing Kluyvera georgiana as the Origin of the Plasmid-Mediated Resistance Gene fosA4

A putative fosA gene in Kluyvera georgiana 14751 showed 99% nucleotide identity with plasmid-encoded fosA4. Due to a single-nucleotide insertion translating to a truncated protein, K. georgiana 14751 fosA does not confer fosfomycin resistance. However, analysis of another genome deposit (Kluyvera ascorbata WCH1410) that could be recategorized as K. georgiana after phylogenetic analysis revealed a fosA gene 100% identical to the plasmid-borne fosA4 gene. We suggest that Kluyvera georgiana represents the most probable origin of fosA4.Fil: Rodriguez, Maria Margarita. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ghiglione, Barbara. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; ArgentinaFil: Power, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; ArgentinaFil: Naas, Thierry. Hôpital de Bicêtre. Service de Bactériologie Hygiène; FranciaFil: Gutkind, Gabriel Osvaldo. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Microbiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin