Ecological Significance of Luminescence in Vibrio cholerae: Occurrence, Structure, Expression, and Function

Several Vibrio species are bioluminescent, including Vibrio cholerae. Analysis of 224 non-pathogenic V. cholerae isolates collected from the Chesapeake Bay, MD, revealed that 52% were luminescent, and 58% of the isolates harbor the luxA gene. A significant association of luxA to the gene stn (r = 0.40) was observed and luminescent strains were found to have a significant association with sample fraction and time of sampling, especially from the observed interaction of these two traits. In contrast, 334 non-pathogenic V. cholerae strains isolated from two rural provinces in Bangladesh, yielded 21 luminescent (6.3%) and 35 luxA+ (10.5%) isolates. None (0%) of 48 laboratory reference pathogenic strains from various geographic locations or 222 environmental and clinical isolated strains of V. cholerae O1 or O139 from Bangladesh were luminescent or harbored the lux operon. To improve success of isolation of V. cholerae from environmental samples, two colony blot hybridization methods were developed. Specificity of two probes was confirmed, using laboratory reference strains, in addition to environmental and clinical isolates, and sensitivity of the probes was confirmed using water samples into which V. cholerae had been inoculated. The lux operon of V. cholerae was sequenced and its chromosomal location determined. The operon organization is most similar to that of Shewanella hanedai and the non-luxF Photobacterium leiognathi. Sequence analysis revealed that the V. cholerae lux operon is most similar in its genomic sequence to V. harveyi and Photorhadbus luminescens and it most likely originated from a common Vibrionaceae ancestor. Using a new bioassay method that measures expression level, several classes of defective luminescent V. cholerae were identified and characterized, including one class previously termed dark, or K variants, in V. harveyi. Multiple causes of the defects were identified, indicating several levels of luminescence control in V. cholerae, in addition to autoinduction and lux repression. Using luxA mutants, luminescence was implicated in conveying competitive advantage in growth under microaerophilic conditions, DNA repair by photoreactivation, and neutralization of reactive oxidative species. These results demonstrate that bioluminescence is a frequently occurring trait in non-pathogenic V. cholerae, the expression of which gives a selective advantage in specific habitats

Occurrence and Diversity of Clinically Important Vibrio Species in the Aquatic Environment of Georgia

Among the more than 70 different Vibrio species inhabiting marine, estuarine, and freshwater ecosystems, 12 are recognized as human pathogens. The warm subtropical climate of the Black Sea coastal area and inland regions of Georgia likely provides a favorable environment for various Vibrio species. From 2006 to 2009, the abundance, ecology, and diversity of clinically important Vibrio species were studied in different locations in Georgia and across seasons. Over a 33-month period, 1,595 presumptive Vibrio isolates were collected from the Black Sea (n=657) and freshwater lakes around Tbilisi (n=938). Screening of a subset of 440 concentrated and enriched water samples by PCR-electrospray ionization/mass spectrometry (PCR-ESI/MS) detected the presence of DNA from eight clinically important Vibrio species: V. cholerae, V. parahaemolyticus, V. vulnificus, V. mimicus, V. alginolyticus, V. harveyi, V. metschnikovii, and V. cincinnatiensis. Almost ninety percent of PCR/ESI-MS samples positive for Vibrio species were collected from June through November. Three important human pathogenic Vibrio species (V. cholerae, V. parahaemolyticus, and V. vulnificus) were detected in 62.8%, 37.8%, and 21.4% of samples testing positive for vibrios, respectively. The results of these activities suggest that natural reservoirs for human-pathogenic Vibrios exist in Georgian aquatic environments. Water temperature at all sampling sites was positively correlated with the abundance of clinically important Vibrio spp. (except V. metschnikovii) and salinity was correlated with species composition at particular Black Sea sites as well as inland reservoirs

Sensor-netting algorithm for CB threat mapping

ABSTRACT Large networks of disparate chemical/biological (CB) sensors, MET sensors, and intelligence, surveillance, and reconnaissance (ISR) sensors reporting to various command/display locations can lead to conflicting threat information, questions of alarm confidence, and a confused situational awareness. Sensor netting algorithms (SNA) are being developed to resolve these conflicts and to report high confidence consensus threat map data products on a common operating picture (COP) display. A phase I SBIR study to develop a conceptual design for a SNA was recently completed. Mathematical approaches for assigning uncertainty to incoming data streams, doing spatial/temporal correlation of point and standoff sensor data (via vector translation based tomography), estimating uncertainty for threat maps, and consistency checking between the consensus threat map result and the individual input data streams were developed. A set of simulation environment tools for testing the SNA, including a simple threat model, sensor models, and fused and un-fused COPs, were also prototyped during phase I. The SNA development and simulation based testing will continue during the phase II effort, which was just awarded

Analysis of Product Range and Proposal of Product Innovations

Diplomová práce se zabývá analýzou sortimentu největšího výrobce stínící techniky v České republice, společnosti SERVIS CLIMAX, a.s. Cílem práce je zjistit postavení výrobkových řad vzhledem k trhu, podniku, konkurenci a životnímu cyklu výrobku. K tomu je využito metod sortimentní analýzy BCG, Hoferovy matice, SWOT analýzy a analýzy konkurence. Analýzy jsou poté vyhodnoceny a na zjištěnou problematiku jsou navrhnuta možná řešení.The subject of the diploma thesis are analysis of product range of the largest manufacturer of shading systems in Czech Republic, company SERVIS CLIMAX, a.s. The aim of the diploma thesis is to determine the position of the product lines in relation to the market, the company, the competition and the life cycle of the product. For this purpose, BCG assortment analysis method, Hofer matrix, SWOT analysis and competition analysis are used. Analyzes are then evaluated and possible solutions are suggested.345 - Katedra mechanické technologievýborn

Germs, Genes, and Memes: Functional and Fitness Dynamics on Information Networks

It is widely accepted that the way information transfers across networks depends importantly on the structure of the network. Here, we show that the mechanism of information transfer is crucial: in many respects the effect of the specific transfer mechanism swamps network effects. Results are demonstrated in terms of three different types of transfer mechanism: germs, genes, and memes. With an emphasis on the specific case of transfer between sub-networks, we explore both the dynamics of each of these across networks and a measure of their comparative fitness. Germ and meme transfer exhibit very different dynamics across linked networks. For germs, measured in terms of time to total infection, network type rather than degree of linkage between sub-networks is the primary factor. For memes or belief transfer, measured in terms of time to consensus, it is the opposite: degree of linkage trumps network type in importance. The dynamics of genetic information transfer is unlike either germs or memes. Transfer of genetic information is robust across network differences to which both germs and memes prove sensitive. We also consider function: how well germ, gene, and meme transfer mechanisms can meet their respective objectives of infecting the population, mixing and transferring genetic information, and spreading a message. A shared formal measure of fitness is introduced for purposes of comparison, again with an emphasis on linked sub-networks. Meme transfer proves superior to transfer by genetic reproduction on that measure, with both memes and genes superior to infection dynamics across all networks types. What kinds of network structure optimize fitness also differ among the three. Both germs and genes show fairly stable fitness with added links between sub-networks, but genes show greater sensitivity to the structure of sub-networks at issue. Belief transfer, in contrast to the other two, shows a clear decline in fitness with increasingly connected networks. When it comes to understanding how information moves on networks, our results indicate that questions of information dynamics on networks cannot be answered in terms of networks alone. A primary role is played by the specific mechanism of information transfer at issue. We must first ask about how a particular type of information moves

Robustness across the Structure of Sub-Networks: The Contrast between Infection and Information Dynamics

In this paper we make a simple theoretical point using a practical issue as an example. The simple theoretical point is that robustness is not 'all or nothing': in asking whether a system is robust one has to ask 'robust with respect to what property?' and 'robust over what set of changes in the system?' The practical issue used to illustrate the point is an examination of degrees of linkage between sub-networks and a pointed contrast in robustness and fragility between the dynamics of (1) contact infection and (2) information transfer or belief change. Time to infection across linked sub-networks, it turns out, is fairly robust with regard to the degree of linkage between them. Time to infection is fragile and sensitive, however, with regard to the type of sub-network involved: total, ring, small world, random, or scale-free. Aspects of robustness and fragility are reversed where it is belief updating with reinforcement rather than infection that is at issue. In information dynamics, the pattern of time to consensus is robust across changes in network type but remarkably fragile with respect to degree of linkage between sub-networks. These results have important implications for public health interventions in realistic social networks, particularly with an eye to ethnic and socio-economic sub-communities, and in social networks with sub-communities changing in structure or linkage

What You Believe Travels Differently: Information and Infection Dynamics Across Sub-Networks

In order to understand the transmission of a disease across a population we will have to understand not only the dynamics of contact infection but the transfer of health-care beliefs and resulting health-care behaviors across that population. This paper is a first step in that direction, focusing on the contrasting role of linkage or isolation between sub-networks in (a) contact infection and (b) belief transfer. Using both analytical tools and agent-based simulations we show that it is the structure of a network that is primary for predicting contact infection—whether the networks or sub-networks at issue are distributed ring networks or total networks (hubs, wheels, small world, random, or scale-free for example). Measured in terms of time to total infection, degree of linkage between sub-networks plays a minor role. The case of belief is importantly different. Using a simplified model of belief reinforcement, and measuring belief transfer in terms of time to community consensus, we show that degree of linkage between sub-networks plays a major role in social communication of beliefs. Here, in contrast to the case of contract infection, network type turns out to be of relatively minor importance. What you believe travels differently. In a final section we show that the pattern of belief transfer exhibits a classic power law regardless of the type of network involved

Interaction of Vibrio cholerae non-O1/non-O139 with Copepods, Cladocerans and Competing Bacteria in the Large Alkaline Lake Neusiedler See, Austria

Vibrio cholerae is a human pathogen and natural inhabitant of aquatic environments. Serogroups O1/O139 have been associated with epidemic cholera, while non-O1/non-O139 serogroups usually cause human disease other than classical cholera. V. cholerae non-O1/non-O139 from the Neusiedler See, a large Central European lake, have caused ear and wound infections, including one case of fatal septicaemia. Recent investigations demonstrated rapid planktonic growth of V. cholerae non-O1/non-O139 and correlation with zooplankton biomass. The aim of this study was to elucidate the interaction of autochthonous V. cholerae with two dominant crustacean zooplankton species in the lake and investigate the influence of the natural bacterial community on this interaction. An existing data set was evaluated for statistical relationships between zooplankton species and V. cholerae and co-culture experiments were performed in the laboratory. A new fluorescence in situ hybridisation protocol was applied for quantification of V. cholerae non-O1/non-O139 cells, which significantly reduced analysis time. The experiments clearly demonstrated a significant relationship of autochthonous V. cholerae non-O1/non-O139 with cladocerans by promoting growth of V. cholerae non-O1/non-O139 in the water and on the surfaces of the cladocerans. In contrast, copepods had a negative effect on the growth of V. cholerae non-O1/non-O139 via competing bacteria from their surfaces. Thus, beside other known factors, biofilm formation by V. cholerae on crustacean zooplankton appears to be zooplankton taxon specific and may be controlled by the natural bacterial community. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00248-010-9764-9) contains supplementary material, which is available to authorized users

Monitoring and Managing the Production Process in a Machinery Company

Import 23/08/2017Bakalářská práce se zaměřuje na aplikaci inovativního způsobu řešení skladového hospodářství s využitím moderních technologií. V úvodu byla provedena analýza záznamu skladových zásob a dále pak skladu samotného. Na základě stanovené analýzy byly definovány potřebné úkony k zavedení moderní technologie do dílčího skladu pohonů. Jedná se především o zavedení čárových kódů do využívaného informačního systému a aplikace identifikačních kódů na jednotlivé položky kompletů pohonů. Dalším bodem návrhu řešení je pokrytí skladu pohonů WiFi signálem pro komfortní využití moderní technologie. Poslední krok byl zaměřen na výběr vhodné techniky pro evidenci skladových zásob, tedy výběrem PDA zařízení, ke kterému bylo využito metody vícekriteriálního rozhodování.Bachelor thesis focuses on the application of an innovative approach to improve a warehouse management while using modern technologies. In the introduction, there was conducted an analysis of the record of inventories and also of the actual stock. Based on the set analysis, there were defined the necessary steps on implication modern technologies into the sub-stock of engines. In particular, it involves the implementation of barcodes into the information system and the implementation of identification codes on individual items of engine sets. Another point of suggested solutions for the engine stock is installation of WiFi modules for convenient use of the modern technology. The last step was directed towards a selection of appropriate technology for record keeping of inventory, therefore to choose a PDA device, which could be used multi-criteria decision-making.345 - Katedra mechanické technologievýborn

Las Vegas Flute Ensemble & UNLV Symphonic Winds

Program listing performers and works performed