935 resultados para Different Beverage Types


Relevância:

80.00% 80.00%

Publicador:

Resumo:

Bacterial cold water disease (BCWD) and rainbow trout fry syndrome (RTFS) caused by Flavobacterium psychrophilum are 2 of the major diseases causing high fish mortality in salmonid fish farms. The molecular epidemiology of F. psychrophilum is still largely unknown. Multilocus sequence typing (MLST) has been previously used for this pathogen and underscored a correlation between clonal complexes and host fish species. Here we used MLST to study the relationships among 112 F. psychrophilum isolates from rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta fario and S. t. lacustris in Swiss fish farms between 1993 and 2012. The isolates belonged to 27 different sequence types (STs). Most of the Swiss outbreaks were associated with strains belonging to clonal complexes CC-ST2 and CC-ST90, found in both rainbow trout and brown trout and represented by several STs. Eight ST singletons could not be connected to any known clonal complex. Already reported from other parts of Europe and North America, CC-ST2 was the most frequent clonal complex observed, and it caused the majority of outbreaks in Switzerland, with CC-ST90 being the second most important type. In the tightly interconnected Swiss fish farms, no association between clonal complex and host fish was detected, but a temporal evolution of the frequency of some STs was observed. The occurrence of sporadic STs suggests high F. psychrophilum diversity and may reflect the presence of different sequence types in the environment.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

BACKGROUND Cats are definitive hosts of Toxoplasma gondii and play an essential role in the epidemiology of this parasite. The study aims at clarifying whether cats are able to develop specific antibodies against different clonal types of T. gondii and to determine by serotyping the T. gondii clonal types prevailing in cats as intermediate hosts in Germany. METHODOLOGY To establish a peptide-microarray serotyping test, we identified 24 suitable peptides using serological T. gondii positive (n=21) and negative cat sera (n=52). To determine the clonal type-specific antibody response of cats in Germany, 86 field sera from T. gondii seropositive naturally infected cats were tested. In addition, we analyzed the antibody response in cats experimentally infected with non-canonical T. gondii types (n=7). FINDINGS Positive cat reference sera reacted predominantly with peptides harbouring amino acid sequences specific for the clonal T. gondii type the cats were infected with. When the array was applied to field sera from Germany, 98.8% (85/86) of naturally-infected cats recognized similar peptide patterns as T. gondii type II reference sera and showed the strongest reaction intensities with clonal type II-specific peptides. In addition, naturally infected cats recognized type II-specific peptides significantly more frequently than peptides of other type-specificities. Cats infected with non-canonical types showed the strongest reactivity with peptides presenting amino-acid sequences specific for both, type I and type III. CONCLUSIONS Cats are able to mount a clonal type-specific antibody response against T. gondii. Serotyping revealed for most seropositive field sera patterns resembling those observed after clonal type II-T. gondii infection. This finding is in accord with our previous results on the occurrence of T. gondii clonal types in oocysts shed by cats in Germany.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Manure scrapers are widely used in dairy cow loose-housing systems. In order to evaluate the effects of the scrapers on the cows, we assessed their impact on the animals' cardiac activity, feeding behaviour, and the behavioural reactions of cows confronted with different types of scrapers. In part I of the study, we measured cardiac activity (mean R–R interval and RMSSD, a parameter of heart-rate variability) whilst observing the behaviour of 29 focal cows on three farms during situations with and without active manure scrapers. Lower RMSSD values were observed during scraping events while cows were either lying, standing or walking in the alleyway, standing completely in the lying cubicle, or standing half in the lying cubicle (P=0.03), but only tended to differ while directly confronted with the scraper (P=0.06). This indicates that dairy cows experienced at least some mild stress during manure-scraping events. In part II, the feeding behaviour of 12 cows on each of two farms was recorded by means of a jaw-movement sensor and compared between situations with the manure-scraping event following forage provision either within or outside the main daily feeding period (i.e. within 1 or after 2 h from forage provisioning, respectively). The duration of night-time feeding (P=0.049) and the number of feeding bouts (P=0.036) were higher when a manure-scraping event took place within the main daily feeding period, indicating that the cows' feeding behaviour had been disturbed. In part III, we observed the cows' behaviour on 15 farms during eight manure scraping events per farm, where each of five farms had one of three different scraper types. We assessed the cows' immediate reactions when confronted with the scraper. In addition, we recorded the number of animals present in the alleyways before and after the manure-scraping events. The more cows that were present in the alleyways before the scraping event, the lower the proportion of cows showing direct behavioural reactions both with (P=0.017) and without (P=0.028) scraper contact, and the higher the number of cows that left the alleyways (P<0.001). Scraper type did not influence the proportion of cows showing behavioural reactions. In conclusion, our results show that dairy cows perceive the manure-scraping event negatively in some situations, that feeding behaviour may be disturbed when scrapers are active during the main feeding period, and that cows avoid the scraper during crowded situations.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The WOCAT network has collected, documented, and assessed more than 350 case studies on promising and good practices of SLM. Information on on- and off-site benefits of different SLM types, as well as on investment and maintenance costs is available, sometimes in quantitative and often in qualitative form. The objective of the present paper is to analyse what kind of economic benefits accrue to local stakeholders, and to better understand how these benefits compare to investment and maintenance costs. The large majority of the technologies contained in the database are perceived by land users as having positive benefits that outweigh costs in the long term. About three quarters of them also have positive or at least neutral benefits in the short term. The analysis shows that many SLM measures exist which can generate important benefits to land users, but also to other stakeholders. However, methodological issues need to be tackled and further quantitative and qualitative data are needed to better understand and support the adoption of SLM measures. Keywords: Sustainable Land Management, Costs, Benefits, Technologies

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Clays and claystones are used as backfill and barrier materials in the design of waste repositories, because they act as hydraulic barriers and retain contaminants. Transport through such barriers occurs mainly by molecular diffusion. There is thus an interest to relate the diffusion properties of clays to their structural properties. In previous work, we have developed a concept for up-scaling pore-scale molecular diffusion coefficients using a grid-based model for the sample pore structure. Here we present an operational algorithm which can generate such model pore structures of polymineral materials. The obtained pore maps match the rock’s mineralogical components and its macroscopic properties such as porosity, grain and pore size distributions. Representative ensembles of grains in 2D or 3D are created by a lattice Monte Carlo (MC) method, which minimizes the interfacial energy of grains starting from an initial grain distribution. Pores are generated at grain boundaries and/or within grains. The method is general and allows to generate anisotropic structures with grains of approximately predetermined shapes, or with mixtures of different grain types. A specific focus of this study was on the simulation of clay-like materials. The generated clay pore maps were then used to derive upscaled effective diffusion coefficients for non-sorbing tracers using a homogenization technique. The large number of generated maps allowed to check the relations between micro-structural features of clays and their effective transport parameters, as is required to explain and extrapolate experimental diffusion results. As examples, we present a set of 2D and 3D simulations and investigated the effects of nanopores within particles (interlayer pores) and micropores between particles. Archie’s simple power law is followed in systems with only micropores. When nanopores are present, additional parameters are required; the data reveal that effective diffusion coefficients could be described by a sum of two power functions, related to the micro- and nanoporosity. We further used the model to investigate the relationships between particle orientation and effective transport properties of the sample.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

BACKGROUND: The Enterococcus faecium genogroup, referred to as clonal complex 17 (CC17), seems to possess multiple determinants that increase its ability to survive and cause disease in nosocomial environments. METHODS: Using 53 clinical and geographically diverse US E. faecium isolates dating from 1971 to 1994, we determined the multilocus sequence type; the presence of 16 putative virulence genes (hyl(Efm), esp(Efm), and fms genes); resistance to ampicillin (AMP) and vancomycin (VAN); and high-level resistance to gentamicin and streptomycin. RESULTS: Overall, 16 different sequence types (STs), mostly CC17 isolates, were identified in 9 different regions of the United States. The earliest CC17 isolates were part of an outbreak that occurred in 1982 in Richmond, Virginia. The characteristics of CC17 isolates included increases in resistance to AMP, the presence of hyl(Efm) and esp(Efm), emergence of resistance to VAN, and the presence of at least 13 of 14 fms genes. Eight of 41 of the early isolates with resistance to AMP, however, were not in CC17. CONCLUSIONS: Although not all early US AMP isolates were clonally related, E. faecium CC17 isolates have been circulating in the United States since at least 1982 and appear to have progressively acquired additional virulence and antibiotic resistance determinants, perhaps explaining the recent success of this species in the hospital environment.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Spiders, as all other arthropods, have an open circulatory system, and their body fluid, the hemolymph, freely moves between lymphatic vessels and the body cavities (see Wirkner and Huckstorf 2013). The hemolymph can be considered as a multifunctional organ, central for locomotion (Kropf 2013), respiration (Burmester 2013) and nutrition, and it amounts to approximately 20 % of a spider’s body weight. Any injury includes not only immediate hemolymph loss but also pathogen attacks and subsequent infections. Therefore spiders have to react to injuries in a combined manner to stop fluid loss and to defend against microbial invaders. This is achieved by an innate immune system which involves several host defence systems such as hemolymph coagulation and the production of a variety of defensive substances (Fukuzawa et al.2008). In spiders, the immune system is localised in hemocytes which are derived from the myocardium cells of the heart wall where they are produced as prohemocytes and from where they are released as different cell types into the hemolymph (Seitz 1972). They contribute to the defence against pathogens by phagocytosis, nodulation and encapsulation of invaders. The humoral response includes mechanisms which induce melanin production to destroy pathogens, a clotting cascade to stop hemolymph loss and the constitutive production of several types of antimicrobial peptides, which are stored in hemocyte granules and released into the hemolymph (Fukuzawa et al.2008) (Fig.7.1). The immune system of spiders is an innate immune system. It is hemolymph-based and characterised by a broad but not very particular specificity. Its advantage is a fast response within minutes to a few hours. This is in contrast to the adaptive immune system of vertebrates which can react to very specific pathogens, thus resulting in much more specific responses. Moreover, it creates an immunological memory during the lifetime of the species. The disadvantage is that it needs more time to react with antibody production, usually many hours to a few days, and needs to be built up during early ontogenesis.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Besides its primary role in producing food and fiber, agriculture also has relevant effects on several other functions, such as management of renewable natural resources. Climate change (CC) may lead to new trade-offs between agricultural functions or aggravate existing ones, but suitable agricultural management may maintain or even improve the ability of agroecosystems to supply these functions. Hence, it is necessary to identify relevant drivers (e.g., cropping practices, local conditions) and their interactions, and how they affect agricultural functions in a changing climate. The goal of this study was to use a modeling framework to analyze the sensitivity of indicators of three important agricultural functions, namely crop yield (food and fiber production function), soil erosion (soil conservation function), and nutrient leaching (clean water provision function), to a wide range of agricultural practices for current and future climate conditions. In a two-step approach, cropping practices that explain high proportions of variance of the different indicators were first identified by an analysis of variance-based sensitivity analysis. Then, most suitable combinations of practices to achieve best performance with respect to each indicator were extracted, and trade-offs were analyzed. The procedure was applied to a region in western Switzerland, considering two different soil types to test the importance of local environmental constraints. Results show that the sensitivity of crop yield and soil erosion due to management is high, while nutrient leaching mostly depends on soil type. We found that the influence of most agricultural practices does not change significantly with CC; only irrigation becomes more relevant as a consequence of decreasing summer rainfall. Trade-offs were identified when focusing on best performances of each indicator separately, and these were amplified under CC. For adaptation to CC in the selected study region, conservation soil management and the use of cropped grasslands appear to be the most suitable options to avoid trade-offs.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The supposed rise of inequality in income and wealth is a much-discussed issue. Since in a number of industrialized countries a trend towards more inequality was observed over the last decades, it is often assumed that Switzerland has experienced a similar development. Yet, although a variety of studies exists that provide inequality estimates for the Swiss society at different points in time, no conclusive picture of the changes in inequality can be drawn from these studies. For example, recent estimates by the Swiss Federal Statistical Office indicate that – against expectations – inequality in disposable equivalent-incomes has not risen since the end of the 1990ies, whereas other studies indicate that earnings from employment – especially top salaries – have become more unequal. The reasons for the inconclusive picture are manifold. For example, trends might have been different for different income types and results might strongly depend on the quality of the used data. To close the knowledge gap in inequality research in Switzerland a new Swiss National Science Foundation project by the University of Bern and the Bern University of Applied Sciences has been started in 2013. Individual tax data from cantons will be analyzed along with aggregate data from the Swiss Federal Tax Administration, covering a period from the early 1970ies to the present. The goal is to gain a systematic overview of the development of inequality in income and wealth in Switzerland as a whole and within cantons, and to determine how changes can be explained. In our talk we will present first results from this project.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The recognition of the importance of mRNA turnover in regulating eukaryotic gene expression has mandated the development of reliable, rigorous, and "user-friendly" methods to accurately measure changes in mRNA stability in mammalian cells. Frequently, mRNA stability is studied indirectly by analyzing the steady-state level of mRNA in the cytoplasm; in this case, changes in mRNA abundance are assumed to reflect only mRNA degradation, an assumption that is not always correct. Although direct measurements of mRNA decay rate can be performed with kinetic labeling techniques and transcriptional inhibitors, these techniques often introduce significant changes in cell physiology. Furthermore, many critical mechanistic issues as to deadenylation kinetics, decay intermediates, and precursor-product relationships cannot be readily addressed by these methods. In light of these concerns, we have previously reported transcriptional pulsing methods based on the c-fos serum-inducible promoter and the tetracycline-regulated (Tet-off) promoter systems to better explain mechanisms of mRNA turnover in mammalian cells. In this chapter, we describe and discuss in detail different protocols that use these two transcriptional pulsing methods. The information described here also provides guidelines to help develop optimal protocols for studying mammalian mRNA turnover in different cell types under a wide range of physiologic conditions.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Development of transcriptional pulsing approaches using the c-fos and Tet-off promoter systems greatly facilitated studies of mRNA turnover in mammalian cells. However, optimal protocols for these approaches vary for different cell types and/or physiological conditions, limiting their widespread application. In this study, we have further optimized transcriptional pulsing systems for different cell lines and developed new protocols to facilitate investigation of various aspects of mRNA turnover. We apply the Tet-off transcriptional pulsing strategy to investigate ARE-mediated mRNA decay in human erythroleukemic K562 cells arrested at various phases of the cell cycle by pharmacological inhibitors. This application facilitates studies of the role of mRNA stability in control of cell-cycle dependent gene expression. To advance the investigation of factors involved in mRNA turnover and its regulation, we have also incorporated recently developed transfection and siRNA reagents into the transcriptional pulsing approach. Using these protocols, siRNA and DNA plasmids can be effectively cotransfected into mouse NIH3T3 cells to obtain high knockdown efficiency. Moreover, we have established a tTA-harboring stable line using human bronchial epithelial BEAS-2B cells and applied the transcriptional pulsing approach to monitor mRNA deadenylation and decay kinetics in this cell system. This broadens the application of the transcriptional pulsing system to investigate the regulation of mRNA turnover related to allergic inflammation. Critical factors that need to be considered when employing these approaches are characterized and discussed.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Ecological networks are typically complex constructions of species and their interactions. During the last decade, the study of networks has moved from static to dynamic analyses, and has attained a deeper insight into their internal structure, heterogeneity, and temporal and spatial resolution. Here, we review, discuss and suggest research lines in the study of the spatio-temporal heterogeneity of networks and their hierarchical nature. We use case study data from two well-characterized model systems (the food web in Broadstone Stream in England and the pollination network at Zackenberg in Greenland), which are complemented with additional information from other studies. We focus upon eight topics: temporal dynamic space-for-time substitutions linkage constraints habitat borders network modularity individual-based networks invasions of networks and super networks that integrate different network types. Few studies have explicitly examined temporal change in networks, and we present examples that span from daily to decadal change: a common pattern that we see is a stable core surrounded by a group of dynamic, peripheral species, which, in pollinator networks enter the web via preferential linkage to the most generalist species. To some extent, temporal and spatial scales are interchangeable (i.e. networks exhibit ‘ergodicity’) and we explore how space-for-time substitutions can be used in the study of networks. Network structure is commonly constrained by phenological uncoupling (a temporal phenomenon), abundance, body size and population structure. Some potential links are never observed, that is they are ‘forbidden’ (fully constrained) or ‘missing’ (a sampling effect), and their absence can be just as ecologically significant as their presence. Spatial habitat borders can add heterogeneity to network structure, but their importance has rarely been studied: we explore how habitat generalization can be related to other resource dimensions. Many networks are hierarchically structured, with modules forming the basic building blocks, which can result in self-similarity. Scaling down from networks of species reveals another, finer-grained level of individual-based organization, the ecological consequences of which have yet to be fully explored. The few studies of individual-based ecological networks that are available suggest the potential for large intraspecific variance and, in the case of food webs, strong size-structuring. However, such data are still scarce and more studies are required to link individual-level and species-level networks. Invasions by alien species can be tracked by following the topological ‘career’ of the invader as it establishes itself within a network, with potentially important implications for conservation biology. Finally, by scaling up to a higher level of organization, it is possible to combine different network types (e.g. food webs and mutualistic networks) to form super networks, and this new approach has yet to be integrated into mainstream ecological research. We conclude by listing a set of research topics that we see as emerging candidates for ecological network studies in the near future.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The aim of this study was to investigate the effects of inner and heard speech on cerebral hemodynamics and oxygenation in the anterior prefrontal cortex (PFC) using functional near-infrared spectroscopy and to test whether potential effects were caused by alterations in the arterial carbon dioxide pressure (PaCO2). Twenty-nine healthy adult volunteers performed six different tasks of inner and heard speech according to a randomized crossover design. During the tasks, we generally found a decrease in PaCO2 (only for inner speech), tissue oxygen saturation (StO2), oxyhemoglobin ([O2Hb]), total hemoglobin ([tHb]) concentration and an increase in deoxyhemoglobin concentration ([HHb]). Furthermore, we found significant relations between changes in [O2Hb], [HHb], [tHb], or StO2 and the participants’ age, the baseline PETCO2, or certain speech tasks. We conclude that changes in breathing during the tasks led to lower PaCO2 (hypocapnia) for inner speech. During heard speech, no significant changes in PaCO2 occurred, but the decreases in StO2, [O2Hb], and [tHb] suggest that changes in PaCO2 were also involved here. Different verse types (hexameter and alliteration) led to different changes in [tHb], implying different brain activations. In conclusion, StO2, [O2Hb], [HHb], and [tHb] are affected by interplay of both PaCO2 reactivity and functional brain activity.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Forty methicillin-resistant and -susceptible Staphylococcus pseudintermedius (MRSP and MSSP, respectively) from colonization and infection in dogs and cats were characterized for clonality, antimicrobial, and biocide susceptibility. MSSP were genetically more diverse than MRSP by multi-locus sequence typing and pulsed-field gel electrophoresis. Three different spa types (t06, t02, t05) and two SCCmec types (II-III and V) were detected in the MRSP isolates. All MRSP and two MSSP strains were multidrug-resistant. Several antibiotic resistance genes (mecA, blaZ, tet(M), tet(K), aac(6')-Ie-aph(2')-Ia, aph(3')-III, ant(6)-Ia, sat4, erm(B), lnu(A), dfr(G), and catpC221) were identified by microarray and double mutations in the gyrA and grlA genes and a single mutation in the rpoB gene were detected by sequence analysis. No differences were detected between MSSP and MRSP in the chlorhexidine acetate (CHA) minimum inhibitory concentrations (MICs). However, two MSSP had elevated MIC to triclosan (TCL) and one to benzalkonium chloride and ethidium bromide. One MSSP isolate harboured a qacA gene, while in another a qacB gene was detected. None of the isolates harboured the sh-fabI gene. Three of the biocide products studied had high bactericidal activity (Otodine(®), Clorexyderm Spot Gel(®), Dermocanis Piocure-M(®)), while Skingel(®) failed to achieve a five log reduction in the bacterial counting. S. pseudintermedius have become a serious therapeutic challenge in particular if methicillin- resistance and/or multidrug-resistance are involved. Biocides, like CHA and TCL, seem to be clinically effective and safe topical therapeutic options.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Background: The aim of the present study was to contributing to researching physiological effects of arts speech therapy by (i) investigating effects of inner and heard speech on cerebral hemodynamics and oxygenation, and (ii) analyzing if these changes were affected by alterations of the arterial carbon dioxide pressure (PaCO2). Methods: In 29 healthy adult volunteers we measured changes in cerebral absolute oxyhemoglobin ([O2Hb]), deoxyhemoglobin ([HHb]), total hemoglobin ([tHb]) concentrations and tissue oxygen saturation (StO2) (over the left and right anterior prefrontal cortex (PFC)) using functional near-infrared spectroscopy (fNIRS) as well as changes in end-tidal CO2 (PETCO2) using capnography. Each subject performed six different tasks: three types of task modalities, i.e. inner speech, heard speech from a person and heard speech from a record, and, two recitation texts, i.e. hexameter and alliteration on different days according to a randomized crossover design. Statistical analysis was applied to the differences between the baseline, two task and four recovery periods. The two brain hemispheres, i.e. left and right PFC, and six tasks were tested separately. Results: During the tasks we found in general a decrease in PETCO2 (significantly only for inner speech), StO2, [O2Hb], [tHb] as well as in an increase in [HHb]. There was a significant difference between hexameter and alliteration. Particularly, the changes in [tHb] at the left PFC during tasks and after them were statistically different. Furthermore we found significant relations between changes in [O2Hb], [HHb], [tHb] or StO2 and the participants’ age, the baseline PETCO2, or certain speech tasks. Conclusions: Changes in breathing (hyperventilation) during the tasks led to lower PaCO2 (hypocapnia) for inner speech. During heard speech no significant changes in PaCO2 occurred, but the decreases in StO2, [O2Hb], [tHb] suggest that changes in PaCO2 were also relevant here. Different verse types (hexameter, alliteration) led to different changes in [tHb]. Consequently, StO2, [O2Hb], [HHb] and [tHb] are affected by interplay of both PaCO2 reactivity and task dependent functional brain activity.