pH Sensitive surfactants from lysine: assessment of their cytotoxicity and environmental behavior

The toxicity and environmental behavior of new pH-sensitive surfactants from lysine are presented. Three different chemical structures are studied: surfactants with one amino acid and one alkyl chain, surfactants with two amino acids on the polar head and one alkyl chain, and gemini surfactants. The pH sensitivity of these compounds can be tuned by modifying their chemical structures. Cytotoxicity has been evaluated using erythrocytes and fibroblast cells. The toxic effects against these cells depend on the hydrophobicity of the molecules as well as their cationic charge density. The effect of hydrophobicity and cationic charge density on toxicity is different for each type of cells. For erythrocytes, the toxicity increases as hydrophobicity and charge density increases. Nevertheless, for fibroblasts cationic charge density affects cytotoxicity in the opposite way: the higher charge density, the lower the toxicity. The effect of the pH on hemolysis has been evaluated in detail. The aquatic toxicity was established using Daphnia magna. All surfactants yielded EC50 values considerably higher than that reported for cationic surfactants based on quaternary ammonium groups. Finally, their biodegradability was evaluated using the CO2 headspace test (ISO 14593). These lysine derivatives showed high levels of biodegradation under aerobic conditions and can be classified as"readily biodegradable compounds".

Potential impact of environmental bacteriophages in spreading antibiotic resistance genes

The idea that bacteriophage transduction plays a role in the horizontal transfer of antibiotic resistance genes is gaining momentum. Such transduction might be vital in horizontal transfer from environmental to human bodyassociated biomes and here we review many lines of evidence supporting this notion. It is well accepted that bacteriophages are the most abundant entities in most environments, where they have been shown to be quite persistent. This fact, together with the ability of many phages to infect bacteria belonging to different taxa, makes them suitable vehicles for gene transfer. Metagenomic studies confirm that substantial percentages of the bacteriophage particles present in most environments contain bacterial genes, including mobile genetic elements and antibiotic resistance genes. When specific genes of resistance to antibiotics are detected by real-time PCR in the bacteriophage populations of different environments, only tenfold lower numbers of these genes are observed, compared with those found in the corresponding bacterial populations. In addition, the antibiotic resistance genes from these bacteriophages are functional and generate resistance to the bacteria when these genes are transfected. Finally, reports about the transduction of antibiotic resistance genes are on the increase.

Growth and functionalization of carbon nanotubes on quartz filter for environmental applications

Background: Air pollution has become an important issue worldwide due to its adverse health effects. Among the different air contaminants, volatile organic compounds (VOCs) are liquids or solids with a high vapor pressure at room temperature that are extremely dangerous for human health. Removal of these compounds can be achieved using nanomaterials with tailored properties such as carbon nanotubes. Methods: Vertically-aligned multiwall carbon nanotubes (CNTs) were successfully grown on quartz filters by means of plasma enhanced chemical vapor deposition (PECVD). Furthermore, a plasma treatment was performed in order to modify the surface properties of the CNTs. The adsorption/desorption processes of three chlorinated compounds (trichloroethylene, 1,2-dichlorobenzene and chloroform) on the CNTs were studied using mass spectrometry measurements with a residual gas analyzer. Results: The adsorption capability of the CNTs increased after functionalization of their surface with a water plasma treatment. In addition, it was found that the presence of aromatic rings, water solubility and polarity of the VOCs play an important role on the adsorption/desorption kinetics at the CNTs surface. Conclusions: This study demonstrates the applicability of CNTs deposited on quartz filters for the removal or selective detection of volatile organic compounds (VOCs). The presence of aromatic rings in VOCs results in π -stacking interactions with a significant increase of their adsorption. On the other hand, it was found that CNTs surface interactions increase with water solubility and polarity of the VOC.

Políticas públicas y sustentabilidad en las zonas desfavorecidas y de montaña en España

El presente trabajo aborda una visión global de la acción pública en los espacios que, en principio, han sido oficial o/y institucionalmente definidos como zonas desfavorecidas o zonas de montaña en España. Territorios, básicamente rurales, que en España muestran un notable grado de heterogeneidad en cuanto a sus estructuras económicas, sociales y culturales, además de caracterizarse por unas estructuras ecológicas igualmente dispares. Esta realidad poliédrica en los últimos años se está viendo condicionada por cuatro factores: las transformaciones internas del sector agroalimentario; los cambios en la organización espacial de la actividad y de la población que son consecuencia de la reestructuración del capitalismo; por las nuevas funciones socioeconómicas, socioculturales y medioambientales que desempeñan estos espacios; y, por el impacto, a veces contradictorio, de las diversas políticas que se implementan sobre ellos, y que se desenvuelven, cada vez más nítidamente, bajo el paradigma del desarrollo sostenible institucional.

Minimization of biosynthetic costs in adaptive gene expression responses of yeast to environmental changes

Yeast successfully adapts to an environmental stress by altering physiology and fine-tuning metabolism. This fine-tuning is achieved through regulation of both gene expression and protein activity, and it is shaped by various physiological requirements. Such requirements impose a sustained evolutionary pressure that ultimately selects a specific gene expression profile, generating a suitable adaptive response to each environmental change. Although some of the requirements are stress specific, it is likely that others are common to various situations. We hypothesize that an evolutionary pressure for minimizing biosynthetic costs might have left signatures in the physicochemical properties of proteins whose gene expression is fine-tuned during adaptive responses. To test this hypothesis we analyze existing yeast transcriptomic data for such responses and investigate how several properties of proteins correlate to changes in gene expression. Our results reveal signatures that are consistent with a selective pressure for economy in protein synthesis during adaptive response of yeast to various types of stress. These signatures differentiate two groups of adaptive responses with respect to how cells manage expenditure in protein biosynthesis. In one group, significant trends towards downregulation of large proteins and upregulation of small ones are observed. In the other group we find no such trends. These results are consistent with resource limitation being important in the evolution of the first group of stress responses.

Molecular method for the characterization of Coxiella burnetii from clinical and environmental samples: variability of genotypes in Spain

Background: Coxiella burnetii is a highly clonal microorganism which is difficult to culture, requiring BSL3 conditions for its propagation. This leads to a scarce availability of isolates worldwide. On the other hand, published methods of characterization have delineated up to 8 different genomic groups and 36 genotypes. However, all these methodologies, with the exception of one that exhibited limited discriminatory power (3 genotypes), rely on performing between 10 and 20 PCR amplifications or sequencing long fragments of DNA, which make their direct application to clinical samples impracticable and leads to a scarce accessibility of data on the circulation of C. burnetii genotypes. Results: To assess the variability of this organism in Spain, we have developed a novel method that consists of a multiplex (8 targets) PCR and hybridization with specific probes that reproduce the previous classification of this organism into 8 genomic groups, and up to 16 genotypes. It allows for a direct haracterization from clinical and environmental samples in a single run, which will help in the study of the different genotypes circulating in wild and domestic cycles as well as from sporadic human cases and outbreaks. The method has been validated with reference isolates. A high variability of C. burnetii has been found in Spain among 90 samples tested, detecting 10 different genotypes, being those adaA negative associated with acute Q fever cases presenting as fever of intermediate duration with liver involvement and with chronic cases. Genotypes infecting humans are also found in sheep, goats, rats, wild boar and ticks, and the only genotype found in cattle has never been found among our clinical samples. Conclusions: This newly developed methodology has permitted to demonstrate that C. burnetii is highly variable in Spain. With the data presented here, cattle seem not to participate in the transmission of C. burnetii to humans in the samples studied, while sheep, goats, wild boar, rats and ticks share genotypes with the human population.

Post-market environmental monitoring of Bt maize in Spain: Non-target effects of varieties derived from the event MON810 on predatory fauna

The Spanish Government has established post-market environmental monitoring (PMEM) as mandatory for genetically modified (GM) crop varieties cultivated in Spain. In order to comply with this regulation, effects of Bt maize varieties derived from the event MON810 on the predatory fauna were monitored for two years in northeast and central Spain. The study was carried out with a randomized block design in maize fields of 3-4 ha on which the abundance of plant-dwelling predators and the activity-density of soil-dwelling predators in Bt vs. non-Bt near-isogenic varieties were compared. To this end, the plots were sampled by visual inspection of a certain number of plants and pitfall traps 6 or 7 times throughout two seasons. No significant differences in predator densities on plants were found between Bt and non-Bt varieties. In the pitfall traps, significant differences between the two types of maize were found only in Staphylinidae, in which trap catches in non-Bt maize were higher than in Bt maize in central Spain. Based on the statistical power of the assays, surrogate arthropods for PMEM purposes are proposed; Orius spp. and Araneae for visual sampling and Carabidae, Araneae, and Staphylinidae for pitfall trapping. The other predator groups recorded in the study, Nabis sp. and Coccinellidae in visual sampling and Dermaptera in pitfall trapping, gave very poor power results. To help to establish a standardized protocol for PMEM of genetically modified crops, the effect-detecting capacity with a power of 0.8 of each predator group is given.

Micronucleus test on Triturus carnifex as a tool for environmental biomonitoring.

The amphibian micronucleus test has been widely used during the last 30 years to test the genotoxic properties of several chemicals and as a tool for ecogenotoxic monitoring. The vast majority of these studies were performed on peripheral blood of urodelan larvae and anuran tadpoles and to a lesser extent adults were also used. In this study, we developed protocols for measuring micronuclei in adult shed skin cells and larval gill cells of the Italian crested newt (Triturus carnifex). Amphibians were collected from ponds in two protected areas in Italy that differed in their radon content. Twenty-three adult newts and 31 larvae were captured from the radon-rich pond, while 20 adults and 27 larvae were taken from the radon-free site. The animals were brought to the laboratory and the micronucleus test was performed on peripheral blood and shed skins taken from the adults and on larval gills. Samples from the radon-rich site showed micronucleus frequencies higher than those from the radon-free site and the difference was statistically significant in gill cells (P < 0.00001). Moreover, the larval gills seem to be more sensitive than the adult tissues. This method represents an easy (and noninvasive in the case of the shed skin) application of the micronucleus assay that can be useful for environmental studies in situ. Environ. Mol. Mutagen. 56:412-417, 2015. © 2014 Wiley Periodicals, Inc.

Du retraité méritant au senior actif : genèse et transformations de la figure sociale de la vieillesse en Suisse

«Crise de l'assurance-vieillesse », «déséquilibre démographique», «vieillissement de la population », « faillite des systèmes de retraite », voilà des expressions qui occupent une place prépondérante dans tes discours portant sur l'avenir de la sécurité sociale aujourd'hui. Les autorités politiques suisses comme européennes font part de leur inquiétude face à la situation d'urgence que présenteraient les « sociétés vieillissantes ». En effet, alors que F assurance-vieillesse s'adressait initialement à une catégorie résiduelle de personnes qui parvenait à vivre plusieurs années au-delà de 65 ans, elle couvre maintenant près d'un cinquième de la population globale. Partant, les autorités fédérales appellent à une restriction des conditions d'accès à la rente de vieillesse. À première vue, les débats qui portent sur cette question dans l'arène politique relèvent de considérations essentiellement techniques liées aux conditions économiques de perpétuation de l'assurances-vieillesse. Il s'agit de modifier les règles d'accès à l'assurance ainsi que le montant des prestations afin d'assainir les caisses tout en faisant face à l'augmentation du nombre de retraités. Ce travail de thèse aborde cette question par une autre approche. Nous partons du postulat que les débats portant sur l'avenir de la politique de la vieillesse sont révélateurs d'une lutte entre acteurs du champ de régulation sociale qui participent d'un travail d'élaboration d'une pensée d'Etat, au sens de P Bourdieu. Cette lutte a pour objet l'imposition de catégories de pensées, soit la définition de ce qu'est un âgé aujourd'hui et de ce qu'il est moralement acceptable d'attendre de lui Nous montrons que cette question peut être comprise à l'aune de l'histoire du traitement social de la vieillesse dont nous relatons ici la genèse et les transformations. Nous soulignons également combien cette pensée d'Etat marque la manière dont les retraités aujourd'hui cherchent à se valoriser face à la déstabilisation de leur statut social. Summary "Crisis of social insurance for older people", "demographic imbalance", "aging of the population", "bankruptcy of pensions systems" ; these are some of the many expressions that today play a importance part in discussion about the future of social security. The Swiss and European political authorities show they are concerned about the crisis that "aging societies" are said to be facing. Indeed, while social insurance for old age used to concern a residual category of people who managet! to live to more than 65 years old, it now covers about a fifth of the global population. Hence, the Federal authorities are calling for a tightening of the conditions for access to retirement benefits. At first glance, the debates in the political arena »elated to (his question mainly deal with technical considerations linked to the economic conditions for the perpetuation of the insurance for old age. Ease of access and the level of the benefits have to be reduced in order to balance the funds, in the face of the rise of the number beneficiaries. This thesis study addresses this question through a different approach. We start from the proposition that debates concerning the future of social policy for old age reveal a struggle between those involved in (he field of social regulation ; this struggle is part of the development of the thought of the State as conceived by P. Bourdieu. The aim of this fight is to impose normative categories of thought, that is to say in relation to our subject, the definition of what an older person is today and what is morally acceptable to expect of him or her. We show that this question can be understood in the light of the the history of the social treatment of old age that we report here. Moreover, we show that this thought of the State explains the way retired people seek to value themselves and confront the destabilisation of their social status.

The UlaG protein familly defines novel structural and functional motifs grafted on an ancient RNase fold

Background: Bacterial populations are highly successful at colonizing new habitats and adapting to changing environmental conditions, partly due to their capacity to evolve novel virulence and metabolic pathways in response to stress conditions and to shuffle them by horizontal gene transfer (HGT). A common theme in the evolution of new functions consists of gene duplication followed by functional divergence. UlaG, a unique manganese-dependent metallo-b-lactamase (MBL) enzyme involved in L-ascorbate metabolism by commensal and symbiotic enterobacteria, provides a model for the study of the emergence of new catalytic activities from the modification of an ancient fold. Furthermore, UlaG is the founding member of the so-called UlaG-like (UlaGL) protein family, a recently established and poorly characterized family comprising divalent (and perhaps trivalent)metal-binding MBLs that catalyze transformations on phosphorylated sugars and nucleotides. Results: Here we combined protein structure-guided and sequence-only molecular phylogenetic analyses to dissect the molecular evolution of UlaG and to study its phylogenomic distribution, its relatedness with present-day UlaGL protein sequences and functional conservation. Phylogenetic analyses indicate that UlaGL sequences are present in Bacteria and Archaea, with bona fide orthologs found mainly in mammalian and plant-associated Gramnegative and Gram-positive bacteria. The incongruence between the UlaGL tree and known species trees indicates exchange by HGT and suggests that the UlaGL-encoding genes provided a growth advantage under changing conditions. Our search for more distantly related protein sequences aided by structural homology has uncovered that UlaGL sequences have a common evolutionary origin with present-day RNA processing and metabolizing MBL enzymes widespread in Bacteria, Archaea, and Eukarya. This observation suggests an ancient origin for the UlaGL family within the broader trunk of the MBL superfamily by duplication, neofunctionalization and fixation. Conclusions: Our results suggest that the forerunner of UlaG was present as an RNA metabolizing enzyme in the last common ancestor, and that the modern descendants of that ancestral gene have a wide phylogenetic distribution and functional roles. We propose that the UlaGL family evolved new metabolic roles among bacterial and possibly archeal phyla in the setting of a close association with metazoans, such as in the mammalian gastrointestinal tract or in animal and plant pathogens, as well as in environmental settings. Accordingly, the major evolutionary forces shaping the UlaGL family include vertical inheritance and lineage-specific duplication and acquisition of novel metabolic functions, followed by HGT and numerous lineage-specific gene loss events.

Testing a new multigroup inference approach to reconstructing past environmental conditions

A new, quantitative, inference model for environmental reconstruction (transfer function), based for the first time on the simultaneous analysis of multigroup species, has been developed. Quantitative reconstructions based on palaeoecological transfer functions provide a powerful tool for addressing questions of environmental change in a wide range of environments, from oceans to mountain lakes, and over a range of timescales, from decades to millions of years. Much progress has been made in the development of inferences based on multiple proxies but usually these have been considered separately, and the different numeric reconstructions compared and reconciled post-hoc. This paper presents a new method to combine information from multiple biological groups at the reconstruction stage. The aim of the multigroup work was to test the potential of the new approach to making improved inferences of past environmental change by improving upon current reconstruction methodologies. The taxonomic groups analysed include diatoms, chironomids and chrysophyte cysts. We test the new methodology using two cold-environment training-sets, namely mountain lakes from the Pyrenees and the Alps. The use of multiple groups, as opposed to single groupings, was only found to increase the reconstruction skill slightly, as measured by the root mean square error of prediction (leave-one-out cross-validation), in the case of alkalinity, dissolved inorganic carbon and altitude (a surrogate for air-temperature), but not for pH or dissolved CO2. Reasons why the improvement was less than might have been anticipated are discussed. These can include the different life-forms, environmental responses and reaction times of the groups under study.

Environmental requirements and environmental management system of boiler plant supplier

Työn tärkeimpänä tavoitteena oli edistää ympäristöjärjestelmän laatimista Kvaerner Pulping, Power divisioonan Kattilat-liiketoimintayksikölle. Lisäksi tavoitteena oli tarkastella yritykseen kohdistuvia ympäristövaatimuksia ja niiden vaikutusta yrityksen toimintaan. Aluksi työssä tarkasteltiin ympäristöjärjestelmästandardien sisältöjä ja niiden eroja. Työssä käsiteltiin myös erilaisia elinkaarijohtamisen malleja, joita voidaan hyödyntää yrityksen kokonaisvaltaisessa ympäristöjärjestelmässä. Työssä tarkasteltiin myös sidosryhmien vaikutusta yrityksen ympäristötoimintaan. Kattilalaitostoimittajan tärkeimpiä asiakkaita ovat sellu- ja paperiteollisuus. Näihin yrityksiin on kohdistunut runsaan kymmenen vuoden aikana paineita ympäristötoiminnan tehostamiseksi. Tämän kehityksen seurauksena vastaavat tehostamispaineet ovat siirtymässä myös alihankkijoille, kuten kattilaitostoimittajille. Tehokkaan ympäristöjohtamisen takaamiseksi työssä määriteltiin ympäristövastuut ja –valtuudet sekä ympäristöpäämäärät ja –tavoitteet. Lisäksi tunnistettiin yrityksen toimintaan liittyvät ympäristönäkökohdat ja –riskit. Työn yhteydessä laadittiin ympäristöjärjestelmän luonnos, ja se sisältää jatkuvan parantamisen periaatteen. Työn yhteydessä laadittiin lisäksi Kvaerner Pulping Oy:n koelaitokselle ympäristölupahakemus. Työssä on kuvattu koelaitosta ja sen ympäristölupahakemukseen liittyviä asioita esimerkkinä parantuneesta ympäristöasioiden hoidosta.