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Sample records for bubonic plague model

  1. Bubonic Plague

    Science.gov (United States)

    ... has the potential to be used as a weapon of bioterrorism; if this were to happen, the ... rat fleas and bubonic plague include India, Vietnam, parts of Africa, and the former Soviet Union. People ...

  2. Human anti-plague monoclonal antibodies protect mice from Yersinia pestis in a bubonic plague model.

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    Xiaodong Xiao

    Full Text Available Yersinia pestis is the etiologic agent of plague that has killed more than 200 million people throughout the recorded history of mankind. Antibiotics may provide little immediate relief to patients who have a high bacteremia or to patients infected with an antibiotic resistant strain of plague. Two virulent factors of Y. pestis are the capsid F1 protein and the low-calcium response (Lcr V-protein or V-antigen that have been proven to be the targets for both active and passive immunization. There are mouse monoclonal antibodies (mAbs against the F1- and V-antigens that can passively protect mice in a murine model of plague; however, there are no anti-Yersinia pestis monoclonal antibodies available for prophylactic or therapeutic treatment in humans. We identified one anti-F1-specific human mAb (m252 and two anti-V-specific human mAb (m253, m254 by panning a naïve phage-displayed Fab library against the F1- and V-antigens. The Fabs were converted to IgG1s and their binding and protective activities were evaluated. M252 bound weakly to peptides located at the F1 N-terminus where a protective mouse anti-F1 mAb also binds. M253 bound strongly to a V-antigen peptide indicating a linear epitope; m254 did not bind to any peptide from a panel of 53 peptides suggesting that its epitope may be conformational. M252 showed better protection than m253 and m254 against a Y, pestis challenge in a plague mouse model. A synergistic effect was observed when the three antibodies were combined. Incomplete to complete protection was achieved when m252 was given at different times post-challenge. These antibodies can be further studied to determine their potential as therapeutics or prophylactics in Y. pestis infection in humans.

  3. Host resistance, population structure and the long-term persistence of bubonic plague: contributions of a modelling approach in the Malagasy focus.

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    Fanny Gascuel

    Full Text Available Although bubonic plague is an endemic zoonosis in many countries around the world, the factors responsible for the persistence of this highly virulent disease remain poorly known. Classically, the endemic persistence of plague is suspected to be due to the coexistence of plague resistant and plague susceptible rodents in natural foci, and/or to a metapopulation structure of reservoirs. Here, we test separately the effect of each of these factors on the long-term persistence of plague. We analyse the dynamics and equilibria of a model of plague propagation, consistent with plague ecology in Madagascar, a major focus where this disease is endemic since the 1920s in central highlands. By combining deterministic and stochastic analyses of this model, and including sensitivity analyses, we show that (i endemicity is favoured by intermediate host population sizes, (ii in large host populations, the presence of resistant rats is sufficient to explain long-term persistence of plague, and (iii the metapopulation structure of susceptible host populations alone can also account for plague endemicity, thanks to both subdivision and the subsequent reduction in the size of subpopulations, and extinction-recolonization dynamics of the disease. In the light of these results, we suggest scenarios to explain the localized presence of plague in Madagascar.

  4. Paleoclimate and bubonic plague: a forewarning of future risk?

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    McMichael Anthony J

    2010-08-01

    Full Text Available Abstract Pandemics of bubonic plague have occurred in Eurasia since the sixth century ad. Climatic variations in Central Asia affect the population size and activity of the plague bacterium's reservoir rodent species, influencing the probability of human infection. Using innovative time-series analysis of surrogate climate records spanning 1,500 years, a study in BMC Biology concludes that climatic fluctuations may have influenced these pandemics. This has potential implications for health risks from future climate change. See research article http://www.biomedcentral.com/1741-7007/8/112

  5. Dissociation of Tissue Destruction and Bacterial Expansion during Bubonic Plague.

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    Françoise Guinet

    2015-10-01

    Full Text Available Activation and/or recruitment of the host plasmin, a fibrinolytic enzyme also active on extracellular matrix components, is a common invasive strategy of bacterial pathogens. Yersinia pestis, the bubonic plague agent, expresses the multifunctional surface protease Pla, which activates plasmin and inactivates fibrinolysis inhibitors. Pla is encoded by the pPla plasmid. Following intradermal inoculation, Y. pestis has the capacity to multiply in and cause destruction of the lymph node (LN draining the entry site. The closely related, pPla-negative, Y. pseudotuberculosis species lacks this capacity. We hypothesized that tissue damage and bacterial multiplication occurring in the LN during bubonic plague were linked and both driven by pPla. Using a set of pPla-positive and pPla-negative Y. pestis and Y. pseudotuberculosis strains in a mouse model of intradermal injection, we found that pPla is not required for bacterial translocation to the LN. We also observed that a pPla-cured Y. pestis caused the same extensive histological lesions as the wild type strain. Furthermore, the Y. pseudotuberculosis histological pattern, characterized by infectious foci limited by inflammatory cell infiltrates with normal tissue density and follicular organization, was unchanged after introduction of pPla. However, the presence of pPla enabled Y. pseudotuberculosis to increase its bacterial load up to that of Y. pestis. Similarly, lack of pPla strongly reduced Y. pestis titers in LNs of infected mice. This pPla-mediated enhancing effect on bacterial load was directly dependent on the proteolytic activity of Pla. Immunohistochemistry of Pla-negative Y. pestis-infected LNs revealed extensive bacterial lysis, unlike the numerous, apparently intact, microorganisms seen in wild type Y. pestis-infected preparations. Therefore, our study demonstrates that tissue destruction and bacterial survival/multiplication are dissociated in the bubo and that the primary action of Pla

  6. Dissociation of Tissue Destruction and Bacterial Expansion during Bubonic Plague.

    Science.gov (United States)

    Guinet, Françoise; Avé, Patrick; Filali, Sofia; Huon, Christèle; Savin, Cyril; Huerre, Michel; Fiette, Laurence; Carniel, Elisabeth

    2015-10-01

    Activation and/or recruitment of the host plasmin, a fibrinolytic enzyme also active on extracellular matrix components, is a common invasive strategy of bacterial pathogens. Yersinia pestis, the bubonic plague agent, expresses the multifunctional surface protease Pla, which activates plasmin and inactivates fibrinolysis inhibitors. Pla is encoded by the pPla plasmid. Following intradermal inoculation, Y. pestis has the capacity to multiply in and cause destruction of the lymph node (LN) draining the entry site. The closely related, pPla-negative, Y. pseudotuberculosis species lacks this capacity. We hypothesized that tissue damage and bacterial multiplication occurring in the LN during bubonic plague were linked and both driven by pPla. Using a set of pPla-positive and pPla-negative Y. pestis and Y. pseudotuberculosis strains in a mouse model of intradermal injection, we found that pPla is not required for bacterial translocation to the LN. We also observed that a pPla-cured Y. pestis caused the same extensive histological lesions as the wild type strain. Furthermore, the Y. pseudotuberculosis histological pattern, characterized by infectious foci limited by inflammatory cell infiltrates with normal tissue density and follicular organization, was unchanged after introduction of pPla. However, the presence of pPla enabled Y. pseudotuberculosis to increase its bacterial load up to that of Y. pestis. Similarly, lack of pPla strongly reduced Y. pestis titers in LNs of infected mice. This pPla-mediated enhancing effect on bacterial load was directly dependent on the proteolytic activity of Pla. Immunohistochemistry of Pla-negative Y. pestis-infected LNs revealed extensive bacterial lysis, unlike the numerous, apparently intact, microorganisms seen in wild type Y. pestis-infected preparations. Therefore, our study demonstrates that tissue destruction and bacterial survival/multiplication are dissociated in the bubo and that the primary action of Pla is to protect

  7. Travel history key to picking up on signs of bubonic plague.

    Science.gov (United States)

    2015-11-01

    Health officials note an uptick in cases of bubonic plague in the United States this year, with at least 12 reported human cases reported since April 1. The CDC notes that healthcare providers should consider plague in patients who have traveled to plague-endemic areas and exhibit fever, headache, chills, weakness, and one or more swollen or tender and painful lymph nodes, referred to as buboes. Officials note that the disease rarely passes from person to person, but that this is a concern with patients who have developed the pneumonic form of the disease. Health officials note that in recent years there has been an average of seven cases of human plague each year in the United States, and that most of these cases are the bubonic form of the illness. Four patients confirmed to have plague this year have died, including the most recent case, a Utah man in his 70s. Most cases of plague in the United States occur in two regions. The first includes northern New Mexico, northern Arizona, and southern Colorado, and the second includes California, southern Oregon, and far western Nevada. When plague is suspected, treatment with antibiotics should begin immediately. PMID:26550675

  8. Effect of the bubonic plague epidemic on inbreeding in 14th century Britain.

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    Pattison, John E

    2003-01-01

    The purpose of the study reported here was to further investigate a new method of estimating inbreeding in large, relatively isolated populations over historic times, as reported by Pattison (1999, 2001). The method is based on modeling the genealogical "paradox" and produces values of Pearl's coefficients of inbreeding as a function of time for any given population curve. In particular, this study demonstrates that the new method of estimating inbreeding may be used to examine the effect of unusual features in population curves on levels of inbreeding in that population. As an example, the medieval population "bump" that spans the 13th and 14th centuries in the population of Britain, which terminated abruptly with the outbreak of bubonic plague in 1348 AD, is examined. It is first assumed that the whole population was the adult (breeding) population, corresponding to minimum inbreeding. For this case it is found that, for distant generations, about 90% of the whole population occurs in any present-day British pedigree. This value compares favorably with the values of 85% and 80% reported by Wachter (1980) and Derrida et al. (1999, 2000), respectively. The population bump causes the curves for Pearl's coefficient, for minimum inbreeding, to have a plateau of about 96% over the period from about 1220 AD to 1380 AD. The effect of introducing a single known estimate of inbreeding into the model is to produce a more realistic situation where the adult (breeding) population is considerably less than the whole population. It is found that the maximum number of different ancestors in any generation, in the average British pedigree, is about 22900 individuals and occurs about 1220 AD. More importantly, and possibly contrary to expectation, it is now found that the population bump had virtually no effect on the level of inbreeding. PMID:12552584

  9. Epidemiologic analysis of a previous outbreak of bubonic plague:The first identified outbreak with bacteriological confirmation in Kobe and Osaka,Japan

    Institute of Scientific and Technical Information of China (English)

    Hiroshi Nishiura

    2009-01-01

    Objective:To characterize the case fatality and estimate the symptomatic period of bubonic plague.Methods:Epidemiologic analyses of a previous outbreak of plague in Osaka and Kobe,two major port cities in Japan, from 1899-1900 were performed.In addition to date of onset of symptoms,gender,age and the date of death were extracted from the historical data.The time from onset to death (symptomatic period)was fitted to gamma distribution using the maximum likelihood method.Results:Temporal distribution revealed suspected chains of transmission of the primary pneumonic plague at the late stage of the outbreak.The case fatality of bubonic plague without specific treatment was 83.4 %,and the mean time from onset to death was estimated as 4.7 days (95 % confidence interval:4.0,5.5).Conclusion:Case fatality of bubonic plague without specific treatment was extremely high.The symptomatic period of bubonic plague appeared to be longer than that of pneumonic plague.

  10. A three-variable chaotic system for the epidemic of bubonic plague in Bombay by the end of the 19th century and its coupling to the epizootics of the two main species of rats

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    Mangiarotti, Sylvain

    2016-04-01

    A plague epidemic broke out in Bombay by the end of the 19th century. A committee was first appointed by the Bombay City [1] in order to stop the epidemic before the rain season started. Unfortunately, the disease could not be stopped and the epidemic became endemic. After several years, another Advisory Committee [2] was appointed that tried to investigate the causes of plague in all possible directions. An impressing quantity of information was gathered during the period 1907-1911 and published. In particular, it was noticed that the epidemic was systematically preceded by epizootics of rats. For this reason, the populations of the main species of rodents were systematically monitored. This data set is revisited here by using a multivariate version of the global modeling technique [3]. The aim of this technique is to obtain a set of Ordinary Differential Equations directly from time series. Three observational time series are considered: the number of person died of bubonic plague per half month (1), and the number of captured infected black rats Mus rattus (2) and brown rats Mus decumanus (3). Several models are obtained, all based on the same algebraic basic structure. These models are, either directly chaotic, or close to chaos (chaos could easily be obtained by tuning one model parameter). The algebraic structure of the simplest model obtained is analyzed in more details. Surprisingly, it is found that the interpretation of the coupling between the three variables can be done term by term. This interpretation is in quite good coherence with the conclusions of the Advisory Committee published one hundred years ago. This structure also shows that the human action to slow down the disease during this period was obviously effective, although insufficient to stop the epidemic drastically. This result suggests that the global modeling technique can be a powerful tool to detect causal couplings in epidemiology, and, more generally, among observational variables from

  11. Small todents fleas from the bubonic plague focus located in the Serra dos Órgãos Mountain Range, State of Rio de Janeiro, Brazil

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    Raimundo Wilson de Carvalho

    2001-07-01

    Full Text Available Eleven species of fleas were collected from 601 small rodents, from November 1995 to October 1997, in areas of natural focus of bubonic plague, including the municipalities of Nova Friburgo, Sumidouro and Teresópolis, State of Rio de Janeiro, Brazil. Among 924 fleas collected, Polygenis (Polygenis rimatus (Rhopalopsyllidae was the predominant species regarding the frequency, representing 41.3% (N:382, followed by P. (Neopolygenis pradoi, representing 20% (N:185 and Craneopsylla minervaminerva (Stephanocircidae, representing 18.9% (N:175. The host Akodon cursor harbored 47.9% of these fleas. Other six host species were infested by 52.1% of the remaining fleas. Fleas were found on hosts and in places within the focus not previously reported by the literature.

  12. Plague

    Science.gov (United States)

    ... Main Content Area Plague Plague is an infectious disease caused by bacteria called Yersinia pestis . These bacteria are found mainly ... States develop plague, according to the Centers for Disease Control and ... cases of human plague are caused by bites of infected animals or the infected ...

  13. Plague

    Science.gov (United States)

    Abbott, Rachel C.; Rocke, Tonie E.

    2012-01-01

    Plague offers readers an overview of this highly complex disease caused by the bacteria Yersinia pestis. The history of the disease, as well as information about Yersinia pestis and its transmission by fleas, is described. The section Geographic Distribution presents areas of the world and United States where plague occurs most commonly in rodents and humans. Species Susceptibility describes infection and disease rates in rodents, humans, and other animals. Disease Ecology considers the complex relationship among rodents, domestic and wild animals, and humans and explores possible routes of transmission and maintenance of the organism in the environment. The effects of climate change, the potential for Y. pestis to be used as a bioweapon, and the impact of plague on conservation of wildlife are considered in Points to Ponder. Disease Prevention and Control outlines methods of prevention and treatment including vaccination for prairie dogs and black-footed ferrets. A glossary of technical terms is included. Tonie E. Rocke, the senior author and an epizootiologist at the USGS National Wildlife Health Center (NWHC), is a prominent researcher on oral vaccination of prairie dogs to prevent plague. She is currently working to transfer her success in the laboratory to the field to control plague in prairie dogs. Rachel C. Abbott, a biologist at the NWHC, is assisting Dr. Rocke in this process and will coordinate field trials of the vaccine. Milt Friend, first director of the NWHC, wrote the foreword. Plague is intended for scholars and the general public. The material is presented in a simple, straightforward manner that serves both audiences. Numerous illustrations and tables provide easily understood summaries of key points and information.

  14. Role of the Yersinia pestis yersiniabactin iron acquisition system in the incidence of flea-borne plague.

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    Florent Sebbane

    Full Text Available Plague is a flea-borne zoonosis caused by the bacterium Yersinia pestis. Y. pestis mutants lacking the yersiniabactin (Ybt siderophore-based iron transport system are avirulent when inoculated intradermally but fully virulent when inoculated intravenously in mice. Presumably, Ybt is required to provide sufficient iron at the peripheral injection site, suggesting that Ybt would be an essential virulence factor for flea-borne plague. Here, using a flea-to-mouse transmission model, we show that a Y. pestis strain lacking the Ybt system causes fatal plague at low incidence when transmitted by fleas. Bacteriology and histology analyses revealed that a Ybt-negative strain caused only primary septicemic plague and atypical bubonic plague instead of the typical bubonic form of disease. The results provide new evidence that primary septicemic plague is a distinct clinical entity and suggest that unusual forms of plague may be caused by atypical Y. pestis strains.

  15. Characterization of systemic and pneumonic murine models of plague infection using a conditionally virulent strain.

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    Mellado-Sanchez, Gabriela; Ramirez, Karina; Drachenberg, Cinthia B; Diaz-McNair, Jovita; Rodriguez, Ana L; Galen, James E; Nataro, James P; Pasetti, Marcela F

    2013-03-01

    Yersinia pestis causes bubonic and pneumonic plague in humans. The pneumonic infection is the most severe and invariably fatal if untreated. Because of its high virulence, ease of delivery and precedent of use in warfare, Y. pestis is considered as a potential bioterror agent. No licensed plague vaccine is currently available in the US. Laboratory research with virulent strains requires appropriate biocontainment (i.e., Biosafety Level 3 (BSL-3) for procedures that generate aerosol/droplets) and secure facilities that comply with federal select agent regulations. To assist in the identification of promising vaccine candidates during the early phases of development, we characterized mouse models of systemic and pneumonic plague infection using the Y. pestis strain EV76, an attenuated human vaccine strain that can be rendered virulent in mice under in vivo iron supplementation. Mice inoculated intranasally or intravenously with Y. pestis EV76 in the presence of iron developed a systemic and pneumonic plague infection that resulted in disease and lethality. Bacteria replicated and severely compromised the spleen, liver and lungs. Susceptibility was age dependent, with younger mice being more vulnerable to pneumonic infection. We used these models of infection to assess the protective capacity of newly developed Salmonella-based plague vaccines. The protective outcome varied depending on the route and dose of infection. Protection was associated with the induction of specific immunological effectors in systemic/mucosal compartments. The models of infection described could serve as safe and practical tools for identifying promising vaccine candidates that warrant further potency evaluation using fully virulent strains in BSL-3 settings. PMID:23195858

  16. Empirical assessment of a threshold model for sylvatic plague

    DEFF Research Database (Denmark)

    Davis, Stephen; Leirs, Herwig; Viljugrein, H.;

    2007-01-01

    Plague surveillance programmes established in Kazakhstan, Central Asia, during the previous century, have generated large plague archives that have been used to parameterize an abundance threshold model for sylvatic plague in great gerbil (Rhombomys opimus) populations. Here, we assess the model ...

  17. Cethromycin-Mediated Protection against the Plague Pathogen Yersinia pestis in a Rat Model of Infection and Comparison with Levofloxacin ▿

    OpenAIRE

    Rosenzweig, Jason A.; Brackman, Sheri M.; Kirtley, Michelle L.; Sha, Jian; Erova, Tatiana E.; Yeager, Linsey A.; Peterson, Johnny W.; Xu, Ze-Qi; Chopra, Ashok K.

    2011-01-01

    The Gram-negative plague bacterium, Yersinia pestis, has historically been regarded as one of the deadliest pathogens known to mankind, having caused three major pandemics. After being transmitted by the bite of an infected flea arthropod vector, Y. pestis can cause three forms of human plague: bubonic, septicemic, and pneumonic, with the latter two having very high mortality rates. With increased threats of bioterrorism, it is likely that a multidrug-resistant Y. pestis strain would be emplo...

  18. The use of high-resolution remote sensing for plague surveillance in Kazakhstan

    DEFF Research Database (Denmark)

    Addink, E A; De Jong, S M; Davis, S A;

    2010-01-01

    Bubonic plague, caused by the bacteria Yersinia pestis, persists as a public health problem in many parts of the world, including central Kazakhstan. Bubonic plague occurs most often in humans through a flea bite, when a questing flea fails to find a rodent host. For many of the plague foci...... expensive and is now under threat due to financial constraints. Previous research showed that the occupancy rate of the burrow systems of the great gerbil is a strong indicator for the probability of a plague outbreak. The burrow systems are around 30 m in diameter with a bare surface. This paper aims...

  19. Modeling Epidemic Spread in Synthetic Populations - Virtual Plagues in Massively Multiplayer Online Games

    CERN Document Server

    Boman, Magnus

    2007-01-01

    A virtual plague is a process in which a behavior-affecting property spreads among characters in a Massively Multiplayer Online Game (MMOG). The MMOG individuals constitute a synthetic population, and the game can be seen as a form of interactive executable model for studying disease spread, albeit of a very special kind. To a game developer maintaining an MMOG, recognizing, monitoring, and ultimately controlling a virtual plague is important, regardless of how it was initiated. The prospect of using tools, methods and theory from the field of epidemiology to do this seems natural and appealing. We will address the feasibility of such a prospect, first by considering some basic measures used in epidemiology, then by pointing out the differences between real world epidemics and virtual plagues. We also suggest directions for MMOG developer control through epidemiological modeling. Our aim is understanding the properties of virtual plagues, rather than trying to eliminate them or mitigate their effects, as woul...

  20. Plague dynamics are driven by climate variation

    DEFF Research Database (Denmark)

    Stenseth, Nils Chr.; Samia, Noelle I.; Viljugrein, Hildegunn;

    2006-01-01

    The bacterium Yersinia pestis causes bubonic plague. In Central Asia, where human plague is still reported regularly, the bacterium is common in natural populations of great gerbils. By using field data from 1949-1995 and previously undescribed statistical techniques, we show that Y. pestis preva...... in the same region, and they are expected to  continue or become more favorable as a result of climate change.  Threats of outbreaks may thus be increasing where humans live in close contact with rodents and fleas (or other wildlife) harboring endemic plague....... prevalence in gerbils increases with warmer springs and wetter summers: A 1°C increase in spring is predicted to lead to a >50% increase in prevalence. Climatic conditions favoring plague apparently existed in this region at the onset of the Black Death as well as when the most recent plague pandemic arose...

  1. Spatial analysis of plague in California: niche modeling predictions of the current distribution and potential response to climate change

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    Tucker James R

    2009-06-01

    Full Text Available Abstract Background Plague, caused by the bacterium Yersinia pestis, is a public and wildlife health concern in California and the western United States. This study explores the spatial characteristics of positive plague samples in California and tests Maxent, a machine-learning method that can be used to develop niche-based models from presence-only data, for mapping the potential distribution of plague foci. Maxent models were constructed using geocoded seroprevalence data from surveillance of California ground squirrels (Spermophilus beecheyi as case points and Worldclim bioclimatic data as predictor variables, and compared and validated using area under the receiver operating curve (AUC statistics. Additionally, model results were compared to locations of positive and negative coyote (Canis latrans samples, in order to determine the correlation between Maxent model predictions and areas of plague risk as determined via wild carnivore surveillance. Results Models of plague activity in California ground squirrels, based on recent climate conditions, accurately identified case locations (AUC of 0.913 to 0.948 and were significantly correlated with coyote samples. The final models were used to identify potential plague risk areas based on an ensemble of six future climate scenarios. These models suggest that by 2050, climate conditions may reduce plague risk in the southern parts of California and increase risk along the northern coast and Sierras. Conclusion Because different modeling approaches can yield substantially different results, care should be taken when interpreting future model predictions. Nonetheless, niche modeling can be a useful tool for exploring and mapping the potential response of plague activity to climate change. The final models in this study were used to identify potential plague risk areas based on an ensemble of six future climate scenarios, which can help public managers decide where to allocate surveillance resources

  2. Modeling the epidemiological history of plague in Central Asia: Palaeoclimatic forcing on a disease system over the past millennium

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    Kausrud Kyrre

    2010-08-01

    Full Text Available Abstract Background Human cases of plague (Yersinia pestis infection originate, ultimately, in the bacterium's wildlife host populations. The epidemiological dynamics of the wildlife reservoir therefore determine the abundance, distribution and evolution of the pathogen, which in turn shape the frequency, distribution and virulence of human cases. Earlier studies have shown clear evidence of climatic forcing on contemporary plague abundance in rodents and humans. Results We find that high-resolution palaeoclimatic indices correlate with plague prevalence and population density in a major plague host species, the great gerbil (Rhombomys opimus, over 1949-1995. Climate-driven models trained on these data predict independent data on human plague cases in early 20th-century Kazakhstan from 1904-1948, suggesting a consistent impact of climate on large-scale wildlife reservoir dynamics influencing human epidemics. Extending the models further back in time, we also find correspondence between their predictions and qualitative records of plague epidemics over the past 1500 years. Conclusions Central Asian climate fluctuations appear to have had significant influences on regional human plague frequency in the first part of the 20th century, and probably over the past 1500 years. This first attempt at ecoepidemiological reconstruction of historical disease activity may shed some light on how long-term plague epidemiology interacts with human activity. As plague activity in Central Asia seems to have followed climate fluctuations over the past centuries, we may expect global warming to have an impact upon future plague epidemiology, probably sustaining or increasing plague activity in the region, at least in the rodent reservoirs, in the coming decades. See commentary: http://www.biomedcentral.com/1741-7007/8/108

  3. [The Justinian plague (part one)].

    Science.gov (United States)

    Sabbatani, Sergio; Manfredi, Roberto; Fiorino, Sirio

    2012-06-01

    In their medical-historical review, the authors assess the evolution of bubonic plague epidemics: after breaking out in the Egyptian port of Pelusium in October 541 AD, the epidemics hit several regions in the Mediterranean basin in a succession of waves. The so-called Justinian plague took its name from the Byzantine emperor of the period, and seriously conditioned the expansionary aims of the Eastern Roman empire towards Italy (which was occupied by Goths), and Northern Africa (where the Vandals had settled), during the first decades of its spread. In the Eastern Empire the plague played a considerable role in reducing the tensions between Persians and Byzantines, especially on the Syrian and Anatolian fronts. It had a major demographic impact, reducing the possibility of recruitment to the Roman legions and leading to a significant drop in tax revenues, which were essential to sustain the state and its military machine. Finally, the plague also took its toll on economic resources (especially agriculture), indirectly leading to a vicious inflationary circle. In the space of over two centuries, plague epidemics paralyzed most trade and commercial exchanges. Furthermore, the Justinian plague, halting the consolidation of the influence of the Eastern Roman empire over some Western regions (including Italy and Northern Africa, which were ruled by Barbarians), supported the development and rise of a number of Roman-Barbarian kingdoms. It may therefore be suggested that the Justinian plague occurred at a very critical historical moment, which represents the real watershed between the Ancient World and the upcoming Middle Ages. PMID:22767313

  4. Prediction of Frost Risks and Plagues using WRF model: a Port Wine region case study

    Science.gov (United States)

    Rodrigues, M. A.; Rocha, A.; Monteiro, A.; Quénol, H.; de Freitas, J. R.

    2012-04-01

    In viticulture where the quality of the wine, the selection of the grapevines or even the characteristics of the farming soil, also depending from local soil features like topography, proximity of a river or water body, will act locally on the weather. Frosts are of significant concern to growers of many cultures crops such as winegrapes. Because of their high latitude and some altitude, the vineyards of the Demarcated Douro Region (DDR) are subjected to the frost, which cause serious damages. But the hazards of vineyard don't confine to the incidents of the fortuitous and meteorological character. The illnesses and plagues affect frequently the vineyards of Demarcated Douro Region due, namely to the weather, to the high power of the regional stocks, to the dense vegetation badly drained and favourable to the setting of numberless fungi, viruses and/or poisonous insects. In the case of DDR it is worth noticing the meteorological conditions due to the weather characteristics. Although there are several illnesses and plagues the most important enemies for the vine in the DDR are the mildew, oidium, grey rottenness, grape moth,. . . , if the climatic conditions favour their appearance and development. For this study, we selected some months for different periods, at the 16 weather stations of the Region of Douro. We use the Weather Research and Forecast Model (WRF) to study and possibly predict the occurrence of risk and plagues (mildew) episodes. The model is first validated with the meteorological data obtained at the weather stations. The knowledge of frost and plagues occurrence allows one to decrease its risks not only by selecting the cultural species and varieties but also the places of growth and the planting and sowing dates.

  5. Clouds continue to plague latest generation climate models

    Science.gov (United States)

    Schultz, Colin

    2012-07-01

    In anticipation of the 2013 publication of the Intergovernmental Panel on Climate Change's fifth assessment report, many in the climate modeling community came together in 2008 under the banner of the Fifth Coupled Model Intercomparison Project (CMIP5). An international effort, this project sought to identify crucial research directions and laid down standardized parameters under which atmosphere-ocean coupled general circulation models (AOGCMs) should be tested so that they can be compared on equal footing. Andrews et al. assessed 15 models participating in the CMIP5 to find the most up-to-date measure of climate sensitivity and the remaining sources of model uncertainty. To test the AOGCMs, the authors looked at how the modeled top-of-the-atmosphere (TOA) radiative emissions from the Earth respond to an imposed change in atmospheric carbon dioxide concentration. Because TOA emissions depend on the global mean atmospheric and surface temperatures, this technique provides an effective way to investigate the feedback mechanisms built into each of the models. The authors assessed model runs for pre-industrial atmospheric carbon dioxide levels as well as those that simulated a sudden quadrupling in the concentration of atmospheric carbon dioxide—the amount that could be reached given a “do nothing” approach to mitigating carbon emissions.

  6. [The spread of the plague: A sciento-historiographic review].

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    Cuadrada, Coral

    2015-01-01

    There is still uncertainty about the diagnosis and nature of the plague; some scholars have been forced to abandon certainties and be filled with doubts: from believing that the mediaeval Black Plague was, in reality, the bubonic plague (although with unusual characteristics) to stating that there is very little evidence to support a retro-diagnosis. This article looks at this in depth, not only reviewing the historiography but also giving new interpretations which question previous hypotheses through research on images of the time, comparing them to the most recent investigative data. Two primary sources are analysed: Renaissance treaties written by four Italian doctors: Michele Savonarola, Marsilio Ficino, Leonardo Fioravanti and Gioseffo Daciano; and iconography: an illustrated manuscript of the Decameron by Giovanni Boccaccio and a Hebrew Haggadah from the XIVth century. The results are compared to the most recent research on DNA and in micropaleontology.

  7. A chaotic model for the plague epidemic that has occurred in Bombay at the end of the 19th century

    Science.gov (United States)

    Mangiarotti, Sylvain

    2015-04-01

    The plague epidemic that has occurred in Bombay at the end of the 19th century was detected in 1896. One year before, an Advisory Committee had been appointed by the Secretary of State for India, the Royal Society, and the Lister Institute. This Committee made numerous investigations and gathered a large panel of data including the number of people attacked and died from the plague, records of rat and flea populations, as well as meteorological records of temperature and humidity [1]. The global modeling technique [2] aims to obtain low dimensional models able to simulate the observed cycles from time series. As far as we know, this technique has been tried only to one case of epidemiological analysis (the whooping cough infection) based on a discrete formulation [3]. In the present work, the continuous time formulation of this technique is used to analyze the time evolution of the plague epidemic from this data set. One low dimensional model (three variables) is obtained exhibiting a limit cycle of period-5. A chaotic behavior could be derived from this model by tuning the model parameters. It provides a strong argument for a dynamical behavior that can be approximated by low dimensional deterministic equations. This model also provides an empirical argument for chaos in epidemics. [1] Verjbitski D. T., Bannerman W. B. & Kápadiâ R. T., 1908. Reports on Plague Investigations in India (May,1908), The Journal of Hygiene, 8(2), 161 -308. [2] Mangiarotti S., Coudret R., Drapeau L. & Jarlan L., 2012. Polynomial search and Global modelling: two algorithms for modeling chaos. Physical Review E, 86(4), 046205. [3] Boudjema G. & Cazelles B., 2003. Extraction of nonlinear dynamics from short and noisy time series. Chaos, Solitons and Fractals, 12, 2051-2069.

  8. Modeling the Impact of White-Plague Coral Disease in Climate Change Scenarios.

    Science.gov (United States)

    Zvuloni, Assaf; Artzy-Randrup, Yael; Katriel, Guy; Loya, Yossi; Stone, Lewi

    2015-06-01

    Coral reefs are in global decline, with coral diseases increasing both in prevalence and in space, a situation that is expected only to worsen as future thermal stressors increase. Through intense surveillance, we have collected a unique and highly resolved dataset from the coral reef of Eilat (Israel, Red Sea), that documents the spatiotemporal dynamics of a White Plague Disease (WPD) outbreak over the course of a full season. Based on modern statistical methodologies, we develop a novel spatial epidemiological model that uses a maximum-likelihood procedure to fit the data and assess the transmission pattern of WPD. We link the model to sea surface temperature (SST) and test the possible effect of increasing temperatures on disease dynamics. Our results reveal that the likelihood of a susceptible coral to become infected is governed both by SST and by its spatial location relative to nearby infected corals. The model shows that the magnitude of WPD epidemics strongly depends on demographic circumstances; under one extreme, when recruitment is free-space regulated and coral density remains relatively constant, even an increase of only 0.5°C in SST can cause epidemics to double in magnitude. In reality, however, the spatial nature of transmission can effectively protect the community, restricting the magnitude of annual epidemics. This is because the probability of susceptible corals to become infected is negatively associated with coral density. Based on our findings, we expect that infectious diseases having a significant spatial component, such as Red-Sea WPD, will never lead to a complete destruction of the coral community under increased thermal stress. However, this also implies that signs of recovery of local coral communities may be misleading; indicative more of spatial dynamics than true rehabilitation of these communities. In contrast to earlier generic models, our approach captures dynamics of WPD both in space and time, accounting for the highly

  9. Modeling the Impact of White-Plague Coral Disease in Climate Change Scenarios.

    Directory of Open Access Journals (Sweden)

    Assaf Zvuloni

    2015-06-01

    Full Text Available Coral reefs are in global decline, with coral diseases increasing both in prevalence and in space, a situation that is expected only to worsen as future thermal stressors increase. Through intense surveillance, we have collected a unique and highly resolved dataset from the coral reef of Eilat (Israel, Red Sea, that documents the spatiotemporal dynamics of a White Plague Disease (WPD outbreak over the course of a full season. Based on modern statistical methodologies, we develop a novel spatial epidemiological model that uses a maximum-likelihood procedure to fit the data and assess the transmission pattern of WPD. We link the model to sea surface temperature (SST and test the possible effect of increasing temperatures on disease dynamics. Our results reveal that the likelihood of a susceptible coral to become infected is governed both by SST and by its spatial location relative to nearby infected corals. The model shows that the magnitude of WPD epidemics strongly depends on demographic circumstances; under one extreme, when recruitment is free-space regulated and coral density remains relatively constant, even an increase of only 0.5°C in SST can cause epidemics to double in magnitude. In reality, however, the spatial nature of transmission can effectively protect the community, restricting the magnitude of annual epidemics. This is because the probability of susceptible corals to become infected is negatively associated with coral density. Based on our findings, we expect that infectious diseases having a significant spatial component, such as Red-Sea WPD, will never lead to a complete destruction of the coral community under increased thermal stress. However, this also implies that signs of recovery of local coral communities may be misleading; indicative more of spatial dynamics than true rehabilitation of these communities. In contrast to earlier generic models, our approach captures dynamics of WPD both in space and time, accounting for

  10. Modeling the ecologic niche of plague in sylvan and domestic animal hosts to delineate sources of human exposure in the western United States.

    Science.gov (United States)

    Walsh, Michael; Haseeb, M A

    2015-01-01

    Plague has been established in the western United States (US) since 1900 following the West Coast introduction of commensal rodents infected with Yersinia pestis via early industrial shipping. Over the last century, plague ecology has transitioned through cycles of widespread human transmission, urban domestic transmission among commensal rodents, and ultimately settled into the predominantly sylvan foci that remain today where it is maintained alternatively by enzootic and epizootic transmission. While zoonotic transmission to humans is much less common in modern times, significant plague risk remains in parts of the western US. Moreover, risk to some threatened species that are part of the epizootic cycle can be quite substantive. This investigation attempted to predict the risk of plague across the western US by modeling the ecologic niche of plague in sylvan and domestic animals identified between 2000 and 2015. A Maxent machine learning algorithm was used to predict this niche based on climate, altitude, land cover, and the presence of an important enzootic species, Peromyscus maniculatus. This model demonstrated good predictive ability (AUC = 86%) and identified areas of high risk in central Colorado, north-central New Mexico, and southwestern and northeastern California. The presence of P. maniculatus, altitude, precipitation during the driest and wettest quarters, and distance to artificial surfaces, all contributed substantively to maximizing the gain function. These findings add to the known landscape epidemiology and infection ecology of plague in the western US and may suggest locations of particular risk to be targeted for wild and domestic animal intervention. PMID:26713244

  11. Enzootic plague foci, Algeria

    Directory of Open Access Journals (Sweden)

    M.A. Malek

    2015-03-01

    Full Text Available In Algeria, PCR sequencing of pla, glpD and rpoB genes found Yersinia pestis in 18/237 (8% rodents of five species, including Apodemus sylvaticus, previously undescribed as pestiferous; and disclosed three new plague foci. Multiple spacer typing confirmed a new Orientalis variant. Rodent survey should be reinforced in this country hosting reemerging plague.

  12. The biblical plague of the Philistines now has a name, tularemia.

    Science.gov (United States)

    Trevisanato, Siro Igino

    2007-01-01

    An epidemic thought to have been the first instance of bubonic plague in the Mediterranean reveals to have been an episode of tularemia. The deadly epidemic took place in the aftermath of the removal of a wooden box from an isolated Hebrew sanctuary. Death, tumors, and rodents thereafter plagued Philistine country. Unlike earlier explanations proposed, tularemia caused by Francisella tularensis exhaustively explains the outbreak. Tularemia fits all the requirements indicated in the biblical text: it is carried by animals, is transmitted to humans, results in the development of ulceroglandular formations, often misdiagnosed for bubonic plague, and is fatal. Moreover, there is the evidence from the box and rodents: mice, which are known carrier for F. tularensis and can communicate it to humans, were credited by the very Philistines to be linked to the outbreak, and are small enough to nest in the box. Mice also explain the otherwise odd statement in the biblical text of a small Philistine idol repeatedly falling on the floor at night in the building where the Philistines had stored the box as mice exiting the box would easily have tipped over the statuette. Tularemia scores yet another point: an episode of the disease is known to have originated in Canaan and spread to Egypt around 1715 BC, indicating recurrence for the disease, and suggesting Canaan was a reservoir for F. tularensis in the 2nd millennium BC. PMID:17467189

  13. Protect Yourself from Plague

    Science.gov (United States)

    ... the groin, armpit or neck. Other symptoms include fever, chills, headache, and extreme exhaustion. A person usually becomes ... plague bacteria infect the lungs. Symptoms include high fever, chills, cough, difficulty breathing, and coughing up bloody mucus. ...

  14. The NlpD lipoprotein is a novel Yersinia pestis virulence factor essential for the development of plague.

    Directory of Open Access Journals (Sweden)

    Avital Tidhar

    Full Text Available Yersinia pestis is the causative agent of plague. Previously we have isolated an attenuated Y. pestis transposon insertion mutant in which the pcm gene was disrupted. In the present study, we investigated the expression and the role of pcm locus genes in Y. pestis pathogenesis using a set of isogenic surE, pcm, nlpD and rpoS mutants of the fully virulent Kimberley53 strain. We show that in Y. pestis, nlpD expression is controlled from elements residing within the upstream genes surE and pcm. The NlpD lipoprotein is the only factor encoded from the pcm locus that is essential for Y. pestis virulence. A chromosomal deletion of the nlpD gene sequence resulted in a drastic reduction in virulence to an LD(50 of at least 10(7 cfu for subcutaneous and airway routes of infection. The mutant was unable to colonize mouse organs following infection. The filamented morphology of the nlpD mutant indicates that NlpD is involved in cell separation; however, deletion of nlpD did not affect in vitro growth rate. Trans-complementation experiments with the Y. pestis nlpD gene restored virulence and all other phenotypic defects. Finally, we demonstrated that subcutaneous administration of the nlpD mutant could protect animals against bubonic and primary pneumonic plague. Taken together, these results demonstrate that Y. pestis NlpD is a novel virulence factor essential for the development of bubonic and pneumonic plague. Further, the nlpD mutant is superior to the EV76 prototype live vaccine strain in immunogenicity and in conferring effective protective immunity. Thus it could serve as a basis for a very potent live vaccine against bubonic and pneumonic plague.

  15. Plague in Central Java, Indonesia

    OpenAIRE

    Williams, J.E.; Hudson, B. W.; Turner, R W; Saroso, J. Sulianti; Cavanaugh, D. C.

    1980-01-01

    Plague in man occurred from 1968 to 1970 in mountain villages of the Boyolali Regency in Central Java. Infected fleas, infected rats, and seropositive rats were collected in villages with human plague cases. Subsequent isolations of Yersinia pestis and seropositive rodents, detected during investigations of rodent plague undertaken by the Government of Indonesia and the WHO, attested to the persistence of plague in the region from 1972 to 1974.

  16. Study on the Basic Plague Pattern of Jianchuan Plague Natural Focus, Yunnan Province, China

    Institute of Scientific and Technical Information of China (English)

    TIAN Jie

    2001-01-01

    Since the plague natural focus of Jianchuan was found in 1974, it had broken the disputation whether Yunnan has plague natural focus among Chinese and foreign scholars for long. Because the focus locates the middle part of transversal mountains with higher biological diversity and complex landscape, many problems raised at beginning in distinguishing the major hosts and vectors, modeling the structure of the focus, and resolving the contradiction between theory and excitation. In review of that, according to the principle of unified of biological structure and function, the basic plague pattern has been systematically studied on through the generalized information concept in this paper. It suggests that the focus takes the community of Apodemus chevrieri + Rattus norvegicus : Neopsylla specialis + Frontopsylla. spadix + Menopsyllus anisus + Loptopsylla segnis as maintenance subsystem, the community of E. miletus:Ctenophthalmus quadratus + Neopsylla specialis as epidematic (amplifying) subsystem, the communities of squirrel rodent-flea as alternate subsystem. The relationship between subsystems is nonlinear. No human plague case is determined by the systematicness of the plague ecosystem. The possibility of human plague will remain in systemic changing or coming into chaos. Although most researches try to analysis of plague as system by means of experiments with many quantitative criterion, these measures are difficult to comprehension the systemic essence without application of the concept of systemic theory. They are often direct, discursive and paradoxical description of appearance rather than the analysis and generalization of interaction relationship between elements, thus reversing the basic ecological concept of Y.pestis as a living thing and agent of plague.

  17. Plague and climate: scales matter

    OpenAIRE

    Ben Ari, Tamara; Neerinckx, Simon; Gage, Kenneth L.; Kreppel, Katharina; Laudisoit, Anne; Leirs, Herwig; Stenseth, Nils Chr

    2011-01-01

    Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large sc...

  18. Plague and climate: scales matter.

    OpenAIRE

    Tamara Ben-Ari; Simon Neerinckx; Gage, Kenneth L.; Katharina Kreppel; Anne Laudisoit; Herwig Leirs; Nils Chr. Stenseth

    2011-01-01

    Plague is enzootic in wildlife populations of small mammals in central and eastern Asia, Africa, South and North America, and has been recognized recently as a reemerging threat to humans. Its causative agent Yersinia pestis relies on wild rodent hosts and flea vectors for its maintenance in nature. Climate influences all three components (i.e., bacteria, vectors, and hosts) of the plague system and is a likely factor to explain some of plague's variability from small and regional to large sc...

  19. [The Justinian plague (part two). Influence of the epidemic on the rise of the Islamic Empire].

    Science.gov (United States)

    Sabbatani, Sergio; Manfredi, Roberto; Fiorino, Sirio

    2012-09-01

    The Islamic Empire started its tumultuous and rapid expansion from the year 622 A.D. (the year of Mohammed's Egira). This rapid growth coincided with the epidemic spread of the bubonic plague in the Middle East. Although a first epidemic event had been documented in the year 570 A.D. (pre-Islamic phase), in the Arabic peninsula, classically according to M.W. Dols five severe episodes of plague sub-epidemics are considered in the middle-eastern geographic area: the first occurred in 627 and 628 A.D., the fifth in 716 A.D.. Anyway, we may state that at the onset of Islam the geographic region including Egypt, Palestine, Syria, Iraq, and Iran was involved by endemic plague. In their work, on the ground of a literature review, the Authors describe the characteristics of the epidemic phenomenon, and analyze the how the plague affected the interpretation of Prophet's Koran and Hadits. The passive attitude demonstrated by many Muslims during early Islam was not shared by all believers, since others moved towards a more soft approach, which included the behaviour of the so called moving aside , when the contagion was of concern. The epidemic plague significantly contributed to the weakening of the Eastern Roman Empire, and the rapid decline of the Persian Empire, while during the early expansion phases of Islam, it indirectly favoured the nomadic Arab tribes which, moving on desert or semi-desert territories, succeeded in escaping the contagion more easily. Subsequently, when the Arab population became sedentary, after occupying the conquered cities, this initial advantage was significantly reduced. PMID:22992565

  20. Predicting Potential Risk Areas of Human Plague for the Western Usambara Mountains, Lushoto District, Tanzania

    DEFF Research Database (Denmark)

    Neerinckx, Simon; Peterson, A Townsend; Gulinck, Hubert;

    2010-01-01

    to explore the geographic distribution and ecology of human plague. Our analyses indicate that plague occurrence is related directly to landscape-scale environmental features, yielding a predictive understanding of one set of environmental factors affecting plague transmission in East Africa. Although many......A natural focus of plague exists in the Western Usambara Mountains of Tanzania. Despite intense research, questions remain as to why and how plague emerges repeatedly in the same suite of villages. We used human plague incidence data for 1986-2003 in an ecological-niche modeling framework...... environmental variables contribute significantly to these models, the most important are elevation and Enhanced Vegetation Index derivatives. Projections of these models across broader regions predict only 15.5% (under a majority-rule threshold) or 31,997 km2 of East Africa as suitable for plague transmission...

  1. Geographic distribution and ecological niche of plague in sub-Saharan Africa

    DEFF Research Database (Denmark)

    Neerinckx, Simon B; Peterson, Andrew T; Gulinck, Hubert;

    2008-01-01

    Background Plague is a rapidly progressing, serious illness in humans that is likely to be fatal if not treated. It remains a public health threat, especially in sub-Saharan Africa. In spite of plague's highly focal nature, a thorough ecological understanding of the general distribution pattern...... of plague across sub-Saharan Africa has not been established to date. In this study, we used human plague data from sub-Saharan Africa for 1970-2007 in an ecological niche modeling framework to explore the potential geographic distribution of plague and its ecological requirements across Africa. Results We...

  2. Lovastatin protects against experimental plague in mice.

    Directory of Open Access Journals (Sweden)

    Saravanan Ayyadurai

    Full Text Available BACKGROUND: Plague is an ectoparasite-borne deadly infection caused by Yersinia pestis, a bacterium classified among the group A bioterrorism agents. Thousands of deaths are reported every year in some African countries. Tetracyclines and cotrimoxazole are used in the secondary prophylaxis of plague in the case of potential exposure to Y. pestis, but cotrimoxazole-resistant isolates have been reported. There is a need for additional prophylactic measures. We aimed to study the effectiveness of lovastatin, a cholesterol-lowering drug known to alleviate the symptoms of sepsis, for plague prophylaxis in an experimental model. METHODOLOGY: Lovastatin dissolved in Endolipide was intraperitoneally administered to mice (20 mg/kg every day for 6 days prior to a Y. pestis Orientalis biotype challenge. Non-challenged, lovastatin-treated and challenged, untreated mice were also used as control groups in the study. Body weight, physical behavior and death were recorded both prior to infection and for 10 days post-infection. Samples of the blood, lungs and spleen were collected from dead mice for direct microbiological examination, histopathology and culture. The potential antibiotic effect of lovastatin was tested on blood agar plates. CONCLUSIONS/SIGNIFICANCE: Lovastatin had no in-vitro antibiotic effect against Y. pestis. The difference in the mortality between control mice (11/15; 73.5% and lovastatin-treated mice (3/15; 20% was significant (P<0.004; Mantel-Haenszel test. Dead mice exhibited Y. pestis septicemia and inflammatory destruction of lung and spleen tissues not seen in lovastatin-treated surviving mice. These data suggest that lovastatin may help prevent the deadly effects of plague. Field observations are warranted to assess the role of lovastatin in the prophylaxis of human plague.

  3. Plague outbreak in Libya, 2009, unrelated to plague in Algeria.

    Science.gov (United States)

    Cabanel, Nicolas; Leclercq, Alexandre; Chenal-Francisque, Viviane; Annajar, Badereddin; Rajerison, Minoarisoa; Bekkhoucha, Souad; Bertherat, Eric; Carniel, Elisabeth

    2013-02-01

    After 25 years of no cases of plague, this disease recurred near Tobruk, Libya, in 2009. An epidemiologic investigation identified 5 confirmed cases. We determined ribotypes, Not1 restriction profiles, and IS100 and IS1541 hybridization patterns of strains isolated during this outbreak. We also analyzed strains isolated during the 2003 plague epidemic in Algeria to determine whether there were epidemiologic links between the 2 events. Our results demonstrate unambiguously that neighboring but independent plague foci coexist in Algeria and Libya. They also indicate that these outbreaks were most likely caused by reactivation of organisms in local or regional foci believed to be dormant (Libya) or extinct (Algeria) for decades, rather than by recent importation of Yersinia pestis from distant foci. Environmental factors favorable for plague reemergence might exist in this area and lead to reactivation of organisms in other ancient foci.

  4. Modeling the ecologic niche of plague in sylvan and domestic animal hosts to delineate sources of human exposure in the western United States

    OpenAIRE

    Walsh, Michael; Haseeb, MA

    2015-01-01

    Plague has been established in the western United States (US) since 1900 following the West Coast introduction of commensal rodents infected with Yersinia pestis via early industrial shipping. Over the last century, plague ecology has transitioned through cycles of widespread human transmission, urban domestic transmission among commensal rodents, and ultimately settled into the predominantly sylvan foci that remain today where it is maintained alternatively by enzootic and epizootic transmis...

  5. Depression Plagues Many with COPD

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_159436.html Depression Plagues Many With COPD Studies found 1 in ... pulmonary disorder (COPD) may raise the risk of depression among patients with the incurable respiratory illness, two ...

  6. Depression Plagues Many with COPD

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159436.html Depression Plagues Many With COPD Studies found 1 in ... pulmonary disorder (COPD) may raise the risk of depression among patients with the incurable respiratory illness, two ...

  7. The Formula of Plague Narratives

    DEFF Research Database (Denmark)

    Christensen, Jørgen Riber

    2015-01-01

    The article is a narratological investigation of a selection of plague tales. The selection spans millennia and different text types, technologies and genres, from The Bible to apocalyptical films, iPhone games and testimonials from Médecins Sans Frontières. The research question is whether it is......, Plague Inc. and testimonials from Médecins Sans Frontières about the 2014-15 ebola outbreak in West Africa....

  8. The threatened plague.

    Science.gov (United States)

    Epstein, P

    1997-01-01

    This article discusses changes in disease patterns affecting human health that may be related to environmental and social changes in the world. The World Health Report reveals that 30 new diseases emerged in the past 20 years. Old diseases are becoming resistant to new drugs. Infectious diseases that were in decline are spreading: diphtheria, whooping cough, and measles. Illnesses such as malaria, fevers, cholera, and rodent-borne viruses are becoming more frequent. Diseases that are transmitted by animals or water are related to environmental and social changes. Degraded environments are susceptible to the appearance of opportunistic species, such as weeds, rodents, insects, and microorganisms. Stable environments support the welfare of large predators and control opportunistic species. Owls, coyotes, and snakes eat rodents that carry Lyme disease ticks and a variety of viruses, plague, and bacteria. Reptiles, birds, spiders, ladybugs, bats, and fish consume larvae and mosquitoes that cause malaria and fevers. Habitat loss and fragmentation, monocultures, excessive use of toxic chemicals, climate change, and weather instability are widespread global changes that reduce the predator population. Small wilderness habitats favor pests. Monocultures reduce genetic diversity and increase vulnerability. Excessive use of pesticides harms birds and helpful insects. A sign of a failing ecosystem is the population explosion of pests and disequilibrium. The Environmental Distress Syndrome is characterized as: 1) emerging infectious diseases, 2) loss of biodiversity, 3) increased generalist species and decreased specialist species, 4) declines in specific specialists, such as pollinators responsible for preservation of flowering plants, and 5) increased coastal algal blooms. The impacts of disease mean considerable costs to humans, agriculture, and livestock. Loss of resources is also costly. PMID:12321043

  9. Plague and the Human Flea, Tanzania

    DEFF Research Database (Denmark)

    Laudisoit, Anne; Leirs, Herwig; Makundi, Rhodes H;

    2007-01-01

    Domestic fleas were collected in 12 villages in the western Usambara Mountains in Tanzania. Of these, 7 are considered villages with high plague frequency, where human plague was recorded during at least 6 of the 17 plague seasons between 1986 and 2004. In the remaining 5 villages with low plague...... frequency, plague was either rare or unrecorded. Pulex irritans, known as the human flea, was the predominant flea species (72.4%) in houses. The density of P. irritans, but not of other domestic fleas, was significantly higher in villages with a higher plague frequency or incidence. Moreover, the P....... irritans index was strongly positively correlated with plague frequency and with the logarithmically transformed plague incidence. These observations suggest that in Lushoto District human fleas may play a role in plague epidemiology. These findings are of immediate public health relevance because...

  10. Plague Bacteria Target Immune Cells During Infection

    OpenAIRE

    Marketon, Melanie M.; DePaolo, R. William; DeBord, Kristin L.; Jabri, Bana; Schneewind, Olaf

    2005-01-01

    The plague is caused by the bacterium Yersinia pestis. Plague bacteria are thought to inject effector Yop proteins into host cells via the type III pathway. The identity of the host cells targeted for injection during plague infection is unknown. We found, using Yop β-lactamase hybrids and fluorescent staining of live cells from plague-infected animals, that Y. pestis selected immune cells for injection. In vivo, dendritic cells, macrophages, and neutrophils were injected most frequently, whe...

  11. Human plague occurrences in Africa

    DEFF Research Database (Denmark)

    Neerinckx, Simon; Bertherat, Eric; Leirs, Herwig

    2010-01-01

    in African countries and compiled information on when, where and how many cases occurred in a centralised database. We found records that plague was probably already present before the third pandemic and that hundreds of thousands of human infections have been reported in 26 countries since 1877...

  12. On Plague in a Time of Ebola

    OpenAIRE

    Ó Gráda, Cormac

    2015-01-01

    Ebola and plague share several characteristics, even though the second and third plague epidemics dwarfed the 2014-15 Ebola outbreak in terms of mortality. This essay reviews the mortality due to the two diseases and their lethality; the spatial and socioeconomic dimensions of plague mortality; the role of public action in containing the two diseases; and their economic impact. non-peer-reviewed

  13. Spread of plague among black-tailed prairie dogs is associated with colony spatial characteristics

    Science.gov (United States)

    Johnson, T.L.; Cully, J.F., Jr.; Collinge, S.K.; Ray, C.; Frey, C.M.; Sandercock, B.K.

    2011-01-01

    Sylvatic plague (Yersinia pestis) is an exotic pathogen that is highly virulent in black-tailed prairie dogs (Cynomys ludovicianus) and causes widespread colony losses and individual mortality rates >95%. We investigated colony spatial characteristics that may influence inter-colony transmission of plague at 3 prairie dog colony complexes in the Great Plains. The 4 spatial characteristics we considered include: colony size, Euclidean distance to nearest neighboring colony, colony proximity index, and distance to nearest drainage (dispersal) corridor. We used multi-state mark-recapture models to determine the relationship between these colony characteristics and probability of plague transmission among prairie dog colonies. Annual mapping of colonies and mark-recapture analyses of disease dynamics in natural colonies led to 4 main results: 1) plague outbreaks exhibited high spatial and temporal variation, 2) the site of initiation of epizootic plague may have substantially influenced the subsequent inter-colony spread of plague, 3) the long-term effect of plague on individual colonies differed among sites because of how individuals and colonies were distributed, and 4) colony spatial characteristics were related to the probability of infection at all sites although the relative importance and direction of relationships varied among sites. Our findings suggest that conventional prairie dog conservation management strategies, including promoting large, highly connected colonies, may need to be altered in the presence of plague. ?? 2011 The Wildlife Society.

  14. Levofloxacin cures experimental pneumonic plague in African green monkeys.

    Directory of Open Access Journals (Sweden)

    Robert Colby Layton

    Full Text Available BACKGROUND: Yersinia pestis, the agent of plague, is considered a potential bioweapon due to rapid lethality when delivered as an aerosol. Levofloxacin was tested for primary pneumonic plague treatment in a nonhuman primate model mimicking human disease. METHODS AND RESULTS: Twenty-four African Green monkeys (AGMs, Chlorocebus aethiops were challenged via head-only aerosol inhalation with 3-145 (mean = 65 50% lethal (LD(50 doses of Y. pestis strain CO92. Telemetered body temperature >39 °C initiated intravenous infusions to seven 5% dextrose controls or 17 levofloxacin treated animals. Levofloxacin was administered as a "humanized" dose regimen of alternating 8 mg/kg and 2 mg/kg 30-min infusions every 24-h, continuing until animal death or 20 total infusions, followed by 14 days of observation. Fever appeared at 53-165 h and radiographs found multilobar pneumonia in all exposed animals. All control animals died of severe pneumonic plague within five days of aerosol exposure. All 16 animals infused with levofloxacin for 10 days survived. Levofloxacin treatment abolished bacteremia within 24 h in animals with confirmed pre-infusion bacteremia, and reduced tachypnea and leukocytosis but not fever during the first 2 days of infusions. CONCLUSION: Levofloxacin cures established pneumonic plague when treatment is initiated after the onset of fever in the lethal aerosol-challenged AGM nonhuman primate model, and can be considered for treatment of other forms of plague. Levofloxacin may also be considered for primary presumptive-use, multi-agent antibiotic in bioterrorism events prior to identification of the pathogen.

  15. Plague metapopulation dynamics in a natural reservoir

    DEFF Research Database (Denmark)

    Davis, S; Klassovskiy, N; Ageyev, V;

    2007-01-01

    The ecology of plague (Yersinia pestis infection) in its ancient foci in Central Asia remains poorly understood. We present field data from two sites in Kazakhstan where the great gerbil (Rhombomys opimus) is the major natural host. Family groups inhabit and defend burrow systems spaced throughout...... the landscape, such that the host population may be considered a metapopulation, with each occupied burrow system a subpopulation. We examine plague transmission within and between family groups and its effect on survival. Transmission of plague occurred disproportionately within family groups although not all......, it is useful to consider the burrow system as the unit of study within a much larger metapopulation....

  16. Sylvatic plague vaccine: combating plague in prarie dogs and black-footed ferrets

    Science.gov (United States)

    Rocke, Tonie E.; Abbott, Rachel C.

    2012-01-01

    After achieving promising results in laboratory trials, researchers at the USGS National Wildlife Health Center (NWHC) and University of Wisconsin at Madison will soon begin field testing a new oral vaccine for sylvatic plague, a devastating disease affecting prairie dogs and other mammals, particularly the endangered black-footed ferret. Our team has developed and is currently registering a sylvatic plague vaccine (SPV) that uses raccoon poxvirus (RCN) to express two key antigens of the Yersinia pestis bacterium, the causative agent of plague.

  17. The trophic responses of two different rodent–vector–plague systems to climate change

    Science.gov (United States)

    Xu, Lei; Schmid, Boris V.; Liu, Jun; Si, Xiaoyan; Stenseth, Nils Chr.; Zhang, Zhibin

    2015-01-01

    Plague, the causative agent of three devastating pandemics in history, is currently a re-emerging disease, probably due to climate change and other anthropogenic changes. Without understanding the response of plague systems to anthropogenic or climate changes in their trophic web, it is unfeasible to effectively predict years with high risks of plague outbreak, hampering our ability for effective prevention and control of the disease. Here, by using surveillance data, we apply structural equation modelling to reveal the drivers of plague prevalence in two very different rodent systems: those of the solitary Daurian ground squirrel and the social Mongolian gerbil. We show that plague prevalence in the Daurian ground squirrel is not detectably related to its trophic web, and that therefore surveillance efforts should focus on detecting plague directly in this ecosystem. On the other hand, plague in the Mongolian gerbil is strongly embedded in a complex, yet understandable trophic web of climate, vegetation, and rodent and flea densities, making the ecosystem suitable for more sophisticated low-cost surveillance practices, such as remote sensing. As for the trophic webs of the two rodent species, we find that increased vegetation is positively associated with higher temperatures and precipitation for both ecosystems. We furthermore find a positive association between vegetation and ground squirrel density, yet a negative association between vegetation and gerbil density. Our study thus shows how past surveillance records can be used to design and improve existing plague prevention and control measures, by tailoring them to individual plague foci. Such measures are indeed highly needed under present conditions with prevailing climate change. PMID:25540277

  18. Burrowing Owls, Pulex irritans, and Plague.

    Science.gov (United States)

    Belthoff, James R; Bernhardt, Scott A; Ball, Christopher L; Gregg, Michael; Johnson, David H; Ketterling, Rachel; Price, Emily; Tinker, Juliette K

    2015-09-01

    Western Burrowing Owls (Athene cunicularia hypugaea) are small, ground-dwelling owls of western North America that frequent prairie dog (Cynomys spp.) towns and other grasslands. Because they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorial mammals, the owls often harbor fleas. We examined the potential role of fleas found on burrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas collected from burrowing owls and in owl blood. During 2012-2013, fleas and blood were collected from burrowing owls in portions of five states with endemic plague-Idaho, Oregon, Washington, Colorado, and South Dakota. Fleas were enumerated, taxonomically identified, pooled by nest, and assayed for Y. pestis using culturing and molecular (PCR) approaches. Owl blood underwent serological analysis for plague antibodies and nested PCR for detection of Y. pestis. Of more than 4750 fleas collected from owls, Pulex irritans, a known plague vector in portions of its range, comprised more than 99.4%. However, diagnostic tests for Y. pestis of flea pools (culturing and PCR) and owl blood (PCR and serology) were negative. Thus, even though fleas were prevalent on burrowing owls and the potential for a relationship with burrowing owls as a phoretic host of infected fleas exists, we found no evidence of Y. pestis in sampled fleas or in owls that harbored them. We suggest that studies similar to those reported here during plague epizootics will be especially useful for confirming these results. PMID:26367482

  19. Current challenges in the development of vaccines for pneumonic plague

    OpenAIRE

    Smiley, Stephen T.

    2008-01-01

    Inhalation of Yersinia pestis bacilli causes pneumonic plague, a rapidly progressing and exceptionally virulent disease. Extensively antibiotic-resistant Y. pestis strains exist and we currently lack a safe and effective pneumonic plague vaccine. These facts raise concern that Y. pestis may be exploited as a bioweapon. Here, I review the history and status of plague vaccine research and advocate that pneumonic plague vaccines should strive to prime both humoral and cellular immunity.

  20. Yersinia pestis with regulated delayed attenuation as a vaccine candidate to induce protective immunity against plague.

    Science.gov (United States)

    Sun, Wei; Roland, Kenneth L; Kuang, Xiaoying; Branger, Christine G; Curtiss, Roy

    2010-03-01

    Two mutant strains of Yersinia pestis KIM5+, a Deltacrp mutant and a mutant with arabinose-dependent regulated delayed-shutoff crp expression (araC P(BAD) crp), were constructed, characterized in vitro, and evaluated for virulence, immunogenicity, and protective efficacy in mice. Both strains were highly attenuated by the subcutaneous (s.c.) route. The 50% lethal doses (LD(50)s) of the Deltacrp and araC P(BAD) crp mutants were approximately 1,000,000-fold and 10,000-fold higher than those of Y. pestis KIM5+, respectively, indicating that both strains were highly attenuated. Mice vaccinated s.c. with 3.8 x 10(7) CFU of the Deltacrp mutant developed high anti-Y. pestis and anti-LcrV serum IgG titers, both with a strong Th2 bias, and induced protective immunity against subcutaneous challenge with virulent Y. pestis (80% survival) but no protection against pulmonary challenge. Mice vaccinated with 3.0 x 10(4) CFU of the araC P(BAD) crp mutant also developed high anti-Y. pestis and anti-LcrV serum IgG titers but with a more balanced Th1/Th2 response. This strain induced complete protection against s.c. challenge and partial protection (70% survival) against pulmonary challenge. Our results demonstrate that arabinose-dependent regulated crp expression is an effective strategy to attenuate Y. pestis while retaining strong immunogenicity, leading to protection against the pneumonic and bubonic forms of plague.

  1. Saving Resources with Plagues in Genetic Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    de Vega, F F; Cantu-Paz, E; Lopez, J I; Manzano, T

    2004-06-15

    The population size of genetic algorithms (GAs) affects the quality of the solutions and the time required to find them. While progress has been made in estimating the population sizes required to reach a desired solution quality for certain problems, in practice the sizing of populations is still usually performed by trial and error. These trials might lead to find a population that is large enough to reach a satisfactory solution, but there may still be opportunities to optimize the computational cost by reducing the size of the population. This paper presents a technique called plague that periodically removes a number of individuals from the population as the GA executes. Recently, the usefulness of the plague has been demonstrated for genetic programming. The objective of this paper is to extend the study of plagues to genetic algorithms. We experiment with deceptive trap functions, a tunable difficult problem for GAs, and the experiments show that plagues can save computational time while maintaining solution quality and reliability.

  2. [The plague in Finland in 1710].

    Science.gov (United States)

    Engström, N G

    1994-01-01

    In the autumn of 1710 Helsinki was struck by the so-called oriental plague during four months. The infection was transferred by black rats which harboured fleas. The flea-bites caused boils. It was believed that the plague was air-borne, and the air was very humid that autumn. Big fires were lit in order to reduce the humidity, the purpose being to make it easier for the infected to breathe. Attempts were also made to dissect the boils. The carriers of the contamination came as refugees from Estland over the Gulf of Finland. The infection had spread from Turkey to Poland and Balticum after the defeat of the Finnish-Swedish army in the summer of 1709 at Poltava in Ucraine. Helsingfors (Helsinki) was struck extremely hard. About two-thirds of the inhabitants died of the pestilence. Some escaped by fleeing to the countryside. The plague spread through the country as far north as to Uleåborg (Oulu) and Cajana (Kajaani). Marketplaces became important centres of infection. With the advent of the frost in December the plague dwindled. At that time Helsinki was practically a dead town. PMID:11640321

  3. Evaluation of Yersinia pestis transmission pathways for sylvatic plague in prairie dog populations in the western U.S.

    Science.gov (United States)

    Richgels, Katherine L. D.; Russell, Robin E.; Bron, Gebbiena; Rocke, Tonie E.

    2016-01-01

    Sylvatic plague, caused by the bacterium Yersinia pestis, is periodically responsible for large die-offs in rodent populations that can spillover and cause human mortalities. In the western US, prairie dog populations experience nearly 100% mortality during plague outbreaks, suggesting that multiple transmission pathways combine to amplify plague dynamics. Several alternate pathways in addition to flea vectors have been proposed, such as transmission via direct contact with bodily fluids or inhalation of infectious droplets, consumption of carcasses, and environmental sources of plague bacteria, such as contaminated soil. However, evidence supporting the ability of these proposed alternate pathways to trigger large-scale epizootics remains elusive. Here we present a short review of potential plague transmission pathways and use an ordinary differential equation model to assess the contribution of each pathway to resulting plague dynamics in black-tailed prairie dogs (Cynomys ludovicianus) and their fleas (Oropsylla hirsuta). Using our model, we found little evidence to suggest that soil contamination was capable of producing plague epizootics in prairie dogs. However, in the absence of flea transmission, direct transmission, i.e., contact with bodily fluids or inhalation of infectious droplets, could produce enzootic dynamics, and transmission via contact with or consumption of carcasses could produce epizootics. This suggests that these pathways warrant further investigation.

  4. Epidemiological analysis of the Eyam plague outbreak of 1665-1666.

    Science.gov (United States)

    Whittles, Lilith K; Didelot, Xavier

    2016-05-11

    Plague, caused by the bacterium Yersinia pestis, is one of the deadliest infectious diseases in human history, and still causes worrying outbreaks in Africa and South America. Despite the historical and current importance of plague, several questions remain unanswered concerning its transmission routes and infection risk factors. The plague outbreak that started in September 1665 in the Derbyshire village of Eyam claimed 257 lives over 14 months, wiping out entire families. Since previous attempts at modelling the Eyam plague, new data have been unearthed from parish records revealing a much more complete record of the disease. Using a stochastic compartmental model and Bayesian analytical methods, we found that both rodent-to-human and human-to-human transmission played an important role in spreading the infection, and that they accounted, respectively, for a quarter and three-quarters of all infections, with a statistically significant seasonality effect. We also found that the force of infection was stronger for infectious individuals living in the same household compared with the rest of the village. Poverty significantly increased the risk of disease, whereas adulthood decreased the risk. These results on the Eyam outbreak contribute to the current debate on the relative importance of plague transmission routes. PMID:27170724

  5. Dog-associated risk factors for human plague.

    Science.gov (United States)

    Gould, L Hannah; Pape, J; Ettestad, P; Griffith, K S; Mead, P S

    2008-10-01

    Plague is a rare but often fatal zoonosis endemic to the western United States. Previous studies have identified contact with pets as a potential risk factor for infection. We conducted a matched case-control study to better define the risks associated with pets at both the household and individual levels. Using a written questionnaire, we surveyed nine surviving plague patients, 12 household members of these patients, and 30 age- and neighbourhood-matched controls about household and individual exposures. Overall, 79% of households had at least one dog, 59% had at least one cat and 33% used flea control, with no significant differences between case and control households. Four (44%) case households reported having a sick dog versus no (0%) control households [matched odds ratio, (mOR) 18.5, 95% confidence interval (CI) 2.3-infinity], and four (44%) patients reported sleeping in the same bed with a pet dog versus three (10%) controls (mOR 5.7, 95% CI 1.0-31.6). Within case households with multiple members, two (40%) of five patients slept with their dogs versus none (0%) of 12 healthy family members (P=0.13). The exposures to cats were not significant. Sleeping in the same bed as a pet dog remained significantly associated with infection in a multivariate logistic regression model (P=0.046). Our findings suggest that dogs may facilitate the transfer of fleas into the home and that activities with close extended contacts with dogs may increase the risk of plague infection. PMID:18489541

  6. Burrowing owls, Pulex irritans and plague

    OpenAIRE

    Belthoff, James R.; Bernhardt, Scott A; Ball, Christopher; Gregg, Michael; Johnson, David H.; Ketterling, Rachel; Price, Emily; Tinker, Juliette K.

    2015-01-01

    Western burrowing owls (Athene cunicularia hypugaea) are small, ground-dwelling owls ofwestern North America that frequent prairie dog (Cynomys spp.) towns and other grasslands.As they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorialmammals, the owls often harbor fleas. We examined the potential role of fleas found onburrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas and inowl blood. During 2012-2013 fleas and blood were ...

  7. The Grape Phylloxera Plague as a Natural Experiment: the Upkeep of Vineyards in Catalonia (Spain), 1858-1935

    OpenAIRE

    Badia-Miró, Marc; Tello, Enric; Valls Junyent, Francesc, 1966-; Garrabou, Ramon,

    2010-01-01

    This paper analyses the impact in Catalonia of the grape Phylloxera plague in Europe (1865-90). A statistical model is used to analyse the economic resilience of 35 districts in Catalonia to this external ecological and economic shock, and to explain why districts in the provinces of Barcelona and Tarragona resumed growing wine grapes after the plague, in contrast to districts in Girona and Lleida provinces. The opportunity cost of labour, the demand pull of Barcelona's commercial growth, and...

  8. War, plague and exploitation in DR Congo

    Directory of Open Access Journals (Sweden)

    Dimčevska Antoaneta K.

    2007-01-01

    Full Text Available Late in autumn 2006 one of the headlines in world media was the first democratic elections in DR Congo. They took place after 30 years of Mobutu Sese Seko’s dictatorship and bloody civil wars in the period 1996-2002. These conflicts, which took approximately 4 million human lives, are called "The First African World War". Elections were held but they did not guarantee the end of trouble for the divided and tormented people in the northeast of Congo, the real scene of bloodshed. The area is still turbulent because it abounds in mineral wealth - gold, diamonds and raw materials for nuclear technology. For a whole decade, unscrupulous actors of the African crisis were fighting there, for illegal profits (achievable in the chaos of bloodshed rather than for democracy, defense of tribal interests, security, etc. as they claimed. In the mines of Eastern Congo unprecedented exploitation of people is still going on, especially of children, victims of conflicts, who suffer in great numbers from violence, starvation and diseases. These slaves of the crisis make local "warlords" and their mentors rich. The looting of the mines has stabilized the crisis because it makes possible enormous accumulation of wealth among armed decision-makers - which also includes availability of countless slaves-miners who have lost everything except their bare lives. Eastern Congo is, however, one of world’s three old focuses of plague; wild exploitation of ores in the area of this endemic disease has activated a sleepy focus and added pneumonic plague to the burdens suffered by the population of the rich but ill-fated region. This was to be expected because endemic plague in the gold-bearing evil circumstances impedes safe mining - and this will be the crucial challenge in the future of Congo. This article is an anthropological outline of the area where gold, plague, weapons and incomparable suffering of people merge together just because of cynic greed producing abuse

  9. [Human factors caused the third plague epidemic in Harbin].

    Science.gov (United States)

    Jin, Dong-Ying; Li, Zhi-Ping

    2011-03-01

    The third plague epidemic in Harbin broke out in 1946 and ended in 1954. Different from the first two plague epidemics (imported), the third prevalence was both imported and idiopathic infectious disease which was caused by human factors. Japanese troops set forbidden zones to build a biological weapon center, which destroyed the natural environment and offered a good growth condition for Citellus Undulatus. In 1945, on the eve of surrender, the Japanese blew up the Unit 731 germ factory located in a bungalow district, which caused diffusion of infected plague fleas. Mice of the district were infected and a man-made plague focus was created. During the prevalence of the third plague, prevention departments at all levels took a series of actions and with people's efforts, the plague was effectively controlled.

  10. Spatial prediction and analysis of Himalayan marmot plague natural epidemic foci in China based on HJ-1 satellite data

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Plague,caused by the gram-negative bacterium Yersinia pestis,is a serious and rapidly progressing illness in humans that can be fatal if not treated effectively.The Qinghai-Tibet Plateau is the largest area of natural Himalayan marmot(Marmota himalayana) plague foci in China and covers more than 630000 km2.Akesai County in Gansu Province is a part of this natural focus of plague and was chosen as a study area.Our study used an ecological niche modeling(ENM) approach to predict the potential distribution of the Himalayan marmot.Environment and Disaster Monitor Satellite(HJ-1) data was used to investigate environment factors that affect plague host animal activity.Host animal point data from active surveillance was combined with environmental variables from the HJ-1 satellite and other databases,and the models of the potential distribution of Himalayan marmot were produced with the Genetic Algorithm for Rule-Set Production(GARP).The probability of marmot presence was divided into 0-5%,5%-20%,20%-40%,40%-80%,and 80%-100% subgroups.Areas with 80%-100% probability exhibited the greatest potential for the presence of Himalayan marmot.According to the predicted potential distribution of Himalayan marmot in the study area,active surveillance of plague hosts and plague control and prevention could be more efficient.

  11. Disease limits populations: plague and black-tailed prairie dogs

    Science.gov (United States)

    Cully, Jack F.; Johnson, T.; Collinge, S.K.; Ray, C.

    2010-01-01

    Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never been affected by the disease. We hypothesized that the presence of plague would significantly reduce overall black-tailed prairie dog colony area, reduce the sizes of colonies on these landscapes, and increase nearest-neighbor distances between colonies. Within the region historically affected by plague, individual colonies were smaller, nearest-neighbor distances were greater, and the proportion of potential habitat occupied by active prairie dog colonies was smaller than at plague-free sites. Populations that endured plague were composed of fewer large colonies (>100 ha) than populations that were historically plague free. We suggest that these differences among sites in colony size and isolation may slow recolonization after extirpation. At the same time, greater intercolony distances may also reduce intercolony transmission of pathogens. Reduced transmission among smaller and more distant colonies may ultimately enhance long-term prairie dog population persistence in areas where plague is present.

  12. A review of plague persistence with special emphasis on fleas

    Directory of Open Access Journals (Sweden)

    Dean E. Biggins

    2009-06-01

    Full Text Available Sylvatic plague is highly prevalent during infrequent epizootics that ravage the landscape of western North America. During these periods, plague dissemination is very efficient. Epizootics end when rodent and flea populations are decimated and vectored transmission declines. A second phase (enzootic plague ensues when plague is difficult to detect from fleas, hosts or the environment, and presents less of a threat to public health. Recently, researchers have hypothesized that the bacterium (Yersinia pestis responsible for plague maintains a continuous state of high virulence and thus only changes in transmission efficiency explain the shift between alternating enzootic and epizootic phases. However, if virulent transmission becomes too inefficient, strong selection might favor an alternate survival strategy. Another plausible non-exclusive hypothesis, best supported from Asian field studies, is that Y. pestis persists (locally at foci by maintaining a more benign relationship within adapted rodents during the long expanses of time between outbreaks. From this vantage, it can revert to the epizootic (transmission efficient form. Similarly, in the United States (US, enzootic plague persistence has been proposed to develop sequestered within New World rodent carriers. However, the absence of clear support for rodent carriers in North America has encouraged a broader search for alternative explanations. A telluric plague existence has been proposed. However, the availability of flea life stages and their hosts could critically supplement environmental plague sources, or fleas might directly represent a lowlevel plague reservoir. Here, we note a potentially pivotal role for fleas. These epizootic plague vectors should be closely studied with newer more exacting methods to determine their potential to serve as participants in or accomplices to a plague persistence reservoir.

  13. Plague and landscape resilience in premodern Iceland.

    Science.gov (United States)

    Streeter, Richard; Dugmore, Andrew J; Vésteinsson, Orri

    2012-03-01

    In debates on societal collapse, Iceland occupies a position of precarious survival, defined by not becoming extinct, like Norse Greenland, but having endured, sometimes by the narrowest of margins. Classic decline narratives for late medieval to early modern Iceland stress compounding adversities, where climate, trade, political domination, unsustainable practices, and environmental degradation conspire with epidemics and volcanism to depress the Icelanders and turn the once-proud Vikings and Saga writers into one of Europe's poorest nations. A mainstay of this narrative is the impact of incidental setbacks such as plague and volcanism, which are seen to have compounded and exacerbated underlying structural problems. This research shows that this view is not correct. We present a study of landscape change that uses 15 precisely dated tephra layers spanning the whole 1,200-y period of human settlement in Iceland. These tephras have provided 2,625 horizons of known age within 200 stratigraphic sections to form a high-resolution spatial and temporal record of change. This finding shows short-term (50 y) declines in geomorphological activity after two major plagues in A.D. 15th century, variations that probably mirrored variations in the population. In the longer term, the geomorphological impact of climate changes from the 14th century on is delayed, and landscapes (as well as Icelandic society) exhibit resilience over decade to century timescales. This finding is not a simple consequence of depopulation but a reflection of how Icelandic society responded with a scaling back of their economy, conservation of core functionality, and entrenchment of the established order.

  14. Plague in Iran: its history and current status

    Science.gov (United States)

    2016-01-01

    OBJECTIVES: Plague remains a public health concern worldwide, particularly in old foci. Multiple epidemics of this disease have been recorded throughout the history of Iran. Despite the long-standing history of human plague in Iran, it remains difficult to obtain an accurate overview of the history and current status of plague in Iran. METHODS: In this review, available data and reports on cases and outbreaks of human plague in the past and present in Iran and in neighboring countries were collected, and information was compiled regarding when, where, and how many cases occurred. RESULTS: This paper considers the history of plague in Persia (the predecessor of today’s Iran) and has a brief review of plague in countries in the World Health Organization Eastern Mediterranean Region, including a range of countries in the Middle East and North Africa. CONCLUSIONS: Since Iran has experienced outbreaks of plague for several centuries, neighboring countries have reported the disease in recent years, the disease can be silent for decades, and the circulation of Yersinia pestis has been reported among rodents and dogs in western Iran, more attention should be paid to disease monitoring in areas with previously reported human cases and in high-risk regions with previous epizootic and enzootic activity. PMID:27457063

  15. The nature of plague in late eighteenth-century Egypt.

    Science.gov (United States)

    Mikhail, Alan

    2008-01-01

    This article uses an examination of the 1791 plague in Egypt to explore the relationships among disease, famine, flood, drought, and death in late eighteenth-century Egypt. It analyzes how plague functioned as part of a regular biophysical pathology of the environment in which the disease came and went as one iteration in a cycle that included famine, wind, flood, drought, price inflation, and revolt. Using the works of Egyptian chroniclers, archival materials, secondary studies, and traveler accounts, this article integrates plague into the study of the Egyptian environment by showing how it was a regular and expected part of life in Egypt. PMID:18622069

  16. [Molecular mechanisms of the plague pathogenic agent interaction with invertebrates].

    Science.gov (United States)

    Kutyrev, V V; Eroshenko, G A; Popov, N V; Vidiaeva, N A; Konnov, N P

    2009-01-01

    Microbe Russian Anti-Plague Research Institute, Saratov, Russia The literature data and experimental results of the authors on the molecular basis of plague agent interaction with invertebrates are discussed. The details of the plague agent life cycle, its genome organization, and molecular genetic mechanisms of its survival in flea vector and on the nematode cuticule are discussed. The experimental data about the ability to form biofilms at abiotic and biotic surfaces in the Yersinia pestis strains of the main and non-main subspecies are presented. Mechanisms of horizontal and vertical transmission of plague agent are considered. The suggestion about participation of the new member in the complex parasitic biocenosis (nematode, vector parasite) is put forward. PMID:20050160

  17. Plague in Arab Maghreb, 1940-2015: a review

    Directory of Open Access Journals (Sweden)

    Maliya Alia Malek

    2016-06-01

    Full Text Available We reviewed the epidemiology of 49 plague outbreaks which resulted in about 7,612 cases in 30 localities in the Arabic Maghreb (Mauritania, Morocco, Algeria, Tunisia, Libya and Egypt over 75 years. Between 1940 and 1950, most cases recorded in Morocco (75% and Egypt (20%, resulted from plague imported to Mediterranean harbours and transmitted by rat ectoparasites. In contrast, the re-emergence of plague in the southern part of Western Sahara in 1953 and in northeast Libya in 1976, was traced to direct contact between nomadic populations and infected goats and camels in natural foci, including the consumption of contaminated meat, illustrating this neglected oral route of contamination. Further familial outbreaks were traced to human ectoparasite transmission. Efforts to identify the factors contributing to natural foci may guide where to focus the surveillance of sentinel animals in order to eradicate human plague, if not Y. pestis from the Arab Maghreb.

  18. Plague in Arab Maghreb, 1940-2015: A Review.

    Science.gov (United States)

    Malek, Maliya Alia; Bitam, Idir; Drancourt, Michel

    2016-01-01

    We reviewed the epidemiology of 49 plague outbreaks that resulted in about 7,612 cases in 30 localities in the Arabic Maghreb (Mauritania, Morocco, Algeria, Tunisia, Libya, and Egypt) over 75 years. Between 1940 and 1950, most cases recorded in Morocco (75%) and Egypt (20%), resulted from plague imported to Mediterranean harbors and transmitted by rat ectoparasites. By contrast, the re-emergence of plague in the southern part of Western Sahara in 1953 and in northeast Libya in 1976 was traced to direct contact between nomadic populations and infected goats and camels in natural foci, including the consumption of contaminated meat, illustrating this neglected oral route of contamination. Further familial outbreaks were traced to human ectoparasite transmission. Efforts to identify the factors contributing to natural foci may guide where to focus the surveillance of sentinel animals in order to eradicate human plague, if not Yersinia pestis from the Arab Maghreb. PMID:27376053

  19. Plague in Arab Maghreb, 1940–2015: A Review

    Science.gov (United States)

    Malek, Maliya Alia; Bitam, Idir; Drancourt, Michel

    2016-01-01

    We reviewed the epidemiology of 49 plague outbreaks that resulted in about 7,612 cases in 30 localities in the Arabic Maghreb (Mauritania, Morocco, Algeria, Tunisia, Libya, and Egypt) over 75 years. Between 1940 and 1950, most cases recorded in Morocco (75%) and Egypt (20%), resulted from plague imported to Mediterranean harbors and transmitted by rat ectoparasites. By contrast, the re-emergence of plague in the southern part of Western Sahara in 1953 and in northeast Libya in 1976 was traced to direct contact between nomadic populations and infected goats and camels in natural foci, including the consumption of contaminated meat, illustrating this neglected oral route of contamination. Further familial outbreaks were traced to human ectoparasite transmission. Efforts to identify the factors contributing to natural foci may guide where to focus the surveillance of sentinel animals in order to eradicate human plague, if not Yersinia pestis from the Arab Maghreb. PMID:27376053

  20. Sylvatic plague vaccine and management of prairie dogs

    Science.gov (United States)

    Rocke, Tonie E.

    2012-01-01

    Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague (Mencher and others, 2004; Rocke and others, 2010). Four species of prairie dogs reside in the United States and Canada, and all are highly susceptible to plague and regularly experience outbreaks with devastating losses. Along with habitat loss and poisoning, plague has contributed to a significant historical decline in prairie dog populations. By some estimates, prairie dogs now occupy only 1 to 2 percent of their former range (Proctor and others, 2006), with prairie dog colonies being now much smaller and fragmented than they were historically, making individual colonies more vulnerable to elimination by plague (Antolin and others, 2002). At least one species, the Utah prairie dog (Cynomys parvidens) is listed by the U.S. Fish and Wildlife Service (FWS) as "threatened." Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods. As an alternative approach, NWHC and UW scientists developed a sylvatic plague vaccine (SPV) for prairie dogs that can be delivered via oral bait. Laboratory studies have shown that consumption of this vaccine-laden bait by different prairie dog species results in significant protection against plague infection that can last for at least 9 months (Rocke and others, 2010; Rocke, unpublished). Work has now shifted to optimizing baits and distribution methods for

  1. Resistance to plague among black-tailed prairie dog populations

    Science.gov (United States)

    Rocke, Tonie E.; Williamson, Judy; Cobble, Kacy R.; Busch, Joseph D.; Antolin, Michael F.; Wagner, David M.

    2012-01-01

    In some rodent species frequently exposed to plague outbreaks caused by Yersinia pestis, resistance to the disease has evolved as a population trait. As a first step in determining if plague resistance has developed in black-tailed prairie dogs (Cynomys ludovicianus), animals captured from colonies in a plague-free region (South Dakota) and two plague-endemic regions (Colorado and Texas) were challenged with Y. pestis at one of three doses (2.5, 250, or 2500 mouse LD50s). South Dakota prairie dogs were far more susceptible to plague than Colorado and Texas prairie dogs (pTexas prairie dogs were quite similar in their response, with overall survival rates of 50% and 60%, respectively. Prairie dogs from these states were heterogenous in their response, with some animals dying at the lowest dose (37% and 20%, respectively) and some surviving even at the highest dose (29% and 40%, respectively). Microsatellite analysis revealed that all three groups were distinct genetically, but further studies are needed to establish a genetic basis for the observed differences in plague resistance.

  2. Resistance to plague among black-tailed prairie dog populations.

    Science.gov (United States)

    Rocke, Tonie E; Williamson, Judy; Cobble, Kacy R; Busch, Joseph D; Antolin, Michael F; Wagner, David M

    2012-02-01

    In some rodent species frequently exposed to plague outbreaks caused by Yersinia pestis, resistance to the disease has evolved as a population trait. As a first step in determining if plague resistance has developed in black-tailed prairie dogs (Cynomys ludovicianus), animals captured from colonies in a plague-free region (South Dakota) and two plague-endemic regions (Colorado and Texas) were challenged with Y. pestis at one of three doses (2.5, 250, or 2500 mouse LD50s). South Dakota prairie dogs were far more susceptible to plague than Colorado and Texas prairie dogs (pTexas prairie dogs were quite similar in their response, with overall survival rates of 50% and 60%, respectively. Prairie dogs from these states were heterogeneous in their response, with some animals dying at the lowest dose (37% and 20%, respectively) and some surviving even at the highest dose (29% and 40%, respectively). Microsatellite analysis revealed that all three groups were distinct genetically, but further studies are needed to establish a genetic basis for the observed differences in plague resistance.

  3. Plague: Infections of Companion Animals and Opportunities for Intervention

    Directory of Open Access Journals (Sweden)

    Petra C.F. Oyston

    2011-06-01

    Full Text Available Plague is a zoonotic disease, normally circulating in rodent populations, transmitted to humans most commonly through the bite of an infected flea vector. Secondary infection of the lungs results in generation of infectious aerosols, which pose a significant hazard to close contacts. In enzootic areas, plague infections have been reported in owners and veterinarians who come into contact with infected pets. Dogs are relatively resistant, but can import infected fleas into the home. Cats are acutely susceptible, and can present a direct hazard to health. Reducing roaming and hunting behaviours, combined with flea control measures go some way to reducing the risk to humans. Various vaccine formulations have been developed which may be suitable to protect companion animals from contracting plague, and thus preventing onward transmission to man. Since transmission has resulted in a number of fatal cases of plague, the vaccination of domestic animals such as cats would seem a low cost strategy for reducing the risk of infection by this serious disease in enzootic regions.

  4. Eighteenth century Yersinia pestis genomes reveal the long-term persistence of an historical plague focus

    OpenAIRE

    Bos, K.; Herbig, A.; Sahl, J; Waglechner, N.; Fourment, M.; Forrest, S; Klunk, J.; Schuenemann, V; Poinar, D.; Kuch, M.; Golding, G.; Dutour, O.; Keim, P; Wagner, D.; Holmes, E

    2016-01-01

    eLife digest A bacterium called Yersina pestis is responsible for numerous human outbreaks of plague throughout history. It is carried by rats and other rodents and can spread to humans causing what we conventionally refer to as plague. The most notorious of these plague outbreaks – the Black Death – claimed millions of lives in Europe in the mid-14th century. Several other plague outbreaks emerged in Europe over the next 400 years. Then, there was a large gap before the plague re-emerged as ...

  5. [The Antonine Plague and the decline of the Roman Empire].

    Science.gov (United States)

    Sabbatani, S; Fiorino, S

    2009-12-01

    The Antonine Plague, which flared up during the reign of Marcus Aurelius from 165 AD and continued under the rule of his son Commodus, played such a major role that the pathocenosis in the Ancient World was changed. The spread of the epidemic was favoured by the occurrence of two military episodes in which Marcus Aurelius himself took part: the Parthian War in Mesopotamia and the wars against the Marcomanni in northeastern Italy, in Noricum and in Pannonia. Accounts of the clinical features of the epidemic are scant and disjointed, with the main source being Galen, who witnessed the plague. Unfortunately, the great physician provides us with only a brief presentation of the disease, his aim being to supply therapeutic approaches, thus passing over the accurate description of the disease symptoms. Although the reports of some clinical cases treated by Galen lead us to think that the Antonine plague was caused by smallpox, palaeopathological confirmation is lacking. Some archaeological evidence (such as terracotta finds) from Italy might reinforce this opinion. In these finds, some details can be observed, suggesting the artist's purpose to represent the classic smallpox pustules, typical signs of the disease. The extent of the epidemic has been extensively debated: the majority of authors agree that the impact of the plague was severe, influencing military conscription, the agricultural and urban economy, and depleting the coffers of the State. The Antonine plague affected ancient Roman traditions, also leaving a mark on artistic expression; a renewal of spirituality and religiousness was recorded. These events created the conditions for the spread of monotheistic religions, such as Mithraism and Christianity. This period, characterized by health, social and economic crises, paved the way for the entry into the Empire of neighbouring barbarian tribes and the recruitment of barbarian troops into the Roman army; these events particularly favoured the cultural and

  6. Colonialism versus Nationalism: The Plague of Hong Kong in 1894

    OpenAIRE

    Lee, PT

    2013-01-01

    Drawing upon different source materials, this paper examines the significance of the plague of Hong Kong in 1894 in two ways. Firstly, it shows the process by which the colonial power successfully implemented the public health policy in Hong Kong by collaborating with the local Chinese communities. Secondly, it demonstrates how the Chinese in Hong Kong responded to the colonial mandatory measures by resisting them or partially accepting them. This paper highlights the reactions of the Chinese...

  7. Sylvatic plague vaccine: A new tool for conservation of threatened and endangered species?

    Science.gov (United States)

    Abbott, Rachel C.; Osorio, Jorge E.; Bunck, Christine M.; Rocke, Tonie E.

    2012-01-01

    Plague, a disease caused by Yersinia pestis introduced into North America about 100 years ago, is devastating to prairie dogs and the highly endangered black-footed ferret. Current attempts to control plague in these species have historically relied on insecticidal dusting of prairie dog burrows to kill the fleas that spread the disease. Although successful in curtailing outbreaks in most instances, this method of plague control has significant limitations. Alternative approaches to plague management are being tested, including vaccination. Currently, all black-footed ferret kits released for reintroduction are vaccinated against plague with an injectable protein vaccine, and even wild-born kits are captured and vaccinated at some locations. In addition, a novel, virally vectored, oral vaccine to prevent plague in wild prairie dogs has been developed and will soon be tested as an alternative, preemptive management tool. If demonstrated to be successful, oral vaccination of selected prairie dog populations could decrease the occurrence of plague epizootics in key locations, thereby reducing the source of bacteria while avoiding the indiscriminate environmental effects of dusting. Just as rabies in wild carnivores has largely been controlled through an active surveillance and oral vaccination program, we believe an integrated plague management strategy would be similarly enhanced with the addition of a cost-effective, bait-delivered, sylvatic plague vaccine for prairie dogs. Control of plague in prairie dogs, and potentially other rodents, would significantly advance prairie dog conservation and black-footed ferret recovery.

  8. Emergence, spread, persistence and fade-out of sylvatic plague in Kazakhstan.

    Science.gov (United States)

    Heier, Lise; Storvik, Geir O; Davis, Stephen A; Viljugrein, Hildegunn; Ageyev, Vladimir S; Klassovskaya, Evgeniya; Stenseth, Nils Chr

    2011-10-01

    Predicting the dynamics of zoonoses in wildlife is important not only for prevention of transmission to humans, but also for improving the general understanding of epidemiological processes. A large dataset on sylvatic plague in the Pre-Balkhash area of Kazakhstan (collected for surveillance purposes) provides a rare opportunity for detailed statistical modelling of an infectious disease. Previous work using these data has revealed a host abundance threshold for epizootics, and climatic influences on plague prevalence. Here, we present a model describing the local space-time dynamics of the disease at a spatial scale of 20 × 20 km(2) and a biannual temporal scale, distinguishing between invasion and persistence events. We used a Bayesian imputation method to account for uncertainties resulting from poor data in explanatory variables and response variables. Spatial autocorrelation in the data was accounted for in imputations and analyses through random effects. The results show (i) a clear effect of spatial transmission, (ii) a high probability of persistence compared with invasion, and (iii) a stronger influence of rodent abundance on invasion than on persistence. In particular, there was a substantial probability of persistence also at low host abundance.

  9. Truth about the Consequence of Bacteriological Warfare of Disseminating Plague Bacteria%散布鼠疫菌(PX)细菌战“战果”之真相

    Institute of Scientific and Technical Information of China (English)

    莇昭三[日](著); 韩慧光(译)

    2015-01-01

    日本军在中国实施细菌战的事实,随着中日学者的研究逐渐被揭示,在研究中所用材料大部分都是加害者(当事人)和受害者的口述史,缺乏日本军当时实施细菌战后对被害地的全面详细的疫学调查。731部队细菌战研究人员金子顺一论文《鼠疫效果略算法》,揭示了1940年农安、新京鼠疫流行事件是731部队实施的细菌战的事实。《陆军军医学校防疫研究报告第2部》中的高桥正彦论文中关于农安、新京鼠疫流行事件的论文,是731部队细菌战后对被害地进行的疫学调查。达格威文件Q报告中的部分数据来自“农安细菌战”受害者的病理解剖,其中不仅有中国人,也有日本人。%Facts about bacteriological warfare conducted by Japanese Army in China have been gradually re-vealed by related Chinese and Japanese researchers. However, the majority of materials used in the research are oral history orally accounted by offenders and victims, hence the lack of epidemic prevention surveys on the inflicted areas of bacteriological warfare by Japanese army. The thesis paper by Jun-Ichi Kaneko (bacterial warfare researcher of U-nit 731) namedBubonicPlagueAlgorithmunveiled the fact that plague epidemics which struck Nong’an and Changchun were caused by the Unit 731’s bacteriological warfare. Takahashi’s thesis paper inArmyMedicalCol-legeEpidemicPreventionResearchReport(VolumeⅡ)on plague epidemics that hit Nong’an and Changchun is in connection with the epidemic prevention surveys on the inflicted areas of bacteriological warfare carried out by the U-nit 731. Some data of the Report of“Q”from Dugway Proving Ground Documents came from pathological anatomy of victims of Nong’an bacteriological warfare, some of whom were Chinese and Japanese.

  10. Identification of duck plague virus by polymerase chain reaction

    Science.gov (United States)

    Hansen, W.R.; Brown, Sean E.; Nashold, S.W.; Knudson, D.L.

    1999-01-01

    A polymerase chain reaction (PCR) assay was developed for detecting duck plague virus. A 765-bp EcoRI fragment cloned from the genome of the duck plague vaccine (DP-VAC) virus was sequenced for PCR primer development. The fragment sequence was found by GenBank alignment searches to be similar to the 3a?? ends of an undefined open reading frame and the gene for DNA polymerase protein in other herpesviruses. Three of four primer sets were found to be specific for the DP-VAC virus and 100% (7/7) of field isolates but did not amplify DNA from inclusion body disease of cranes virus. The specificity of one primer set was tested with genome templates from other avian herpesviruses, including those from a golden eagle, bald eagle, great horned owl, snowy owl, peregrine falcon, prairie falcon, pigeon, psittacine, and chicken (infectious laryngotracheitis), but amplicons were not produced. Hence, this PCR test is highly specific for duck plague virus DNA. Two primer sets were able to detect 1 fg of DNA from the duck plague vaccine strain, equivalent to five genome copies. In addition, the ratio of tissue culture infectious doses to genome copies of duck plague vaccine virus from infected duck embryo cells was determined to be 1:100, making the PCR assay 20 times more sensitive than tissue culture for detecting duck plague virus. The speed, sensitivity, and specificity of this PCR provide a greatly improved diagnostic and research tool for studying the epizootiology of duck plague. /// Se desarroll?? una prueba de reacci??n en cadena por la polimerasa para detectar el virus de la peste del pato. Un fragmento EcoRI de 765 pares de bases clonado del genoma del virus vacunal de la peste del pato fue secuenciado para la obtenci??n de los iniciadores de la prueba de la reacci??n en cadena por la polimerasa. En investigaciones de alineaci??n en el banco de genes ('GenBank') se encontr?? que la secuencia del fragmento era similar a los extremos 3a?? de un marco de lectura abierto

  11. The Role of Transition Metal Transporters for Iron, Zinc, Manganese, and Copper in the Pathogenesis of Yersinia pestis

    Science.gov (United States)

    Perry, Robert D.; Bobrov, Alexander G.; Fetherston, Jacqueline D.

    2015-01-01

    Yersinia pestis, the causative agent of bubonic, septicemic and pneumonic plague, encodes a multitude of Fe transport systems. Some of these are defective due to frameshift or IS element insertions, while others are functional in vitro but have no established role in causing infections. Indeed only 3 Fe transporters (Ybt, Yfe and Feo) have been shown to be important in at least one form of plague. The yersiniabactin (Ybt) system is essential in the early dermal/lymphatic stages of bubonic plague, irrelevant in the septicemic stage, and critical in pneumonic plague. Two Mn transporters have been characterized (Yfe and MntH). These two systems play a role in bubonic plague but the double yfe mntH mutant is fully virulent in a mouse model of pneumonic plague. The same in vivo phenotype occurs with a mutant lacking two (Yfe and Feo) of four ferrous transporters. A role for the Ybt siderophore in Zn acquisition has been revealed. Ybt-dependent Zn acquisition uses a transport system completely independent of the Fe-Ybt uptake system. Together Ybt components and ZnuABC play a critical role in Zn acquisition in vivo. Single mutants in either system retain high virulence in a mouse model of septicemic plague while the double mutant is completely avirulent. PMID:25891079

  12. Identification of a Yersinia pestis-specific DNA probe with potential for use in plague surveillance.

    OpenAIRE

    McDonough, K A; Schwan, T G; Thomas, R.E.; Falkow, S

    1988-01-01

    A 900-base-pair DNA fragment derived from a 9.5-kilobase plasmid in Yersinia pestis hybridized specifically with Y. pestis DNA. We demonstrated the feasibility of using this DNA fragment to detect plague bacilli directly in fleas, suggesting that this Y. pestis-specific DNA probe may be used for plague surveillance in the field. Additional applications for this DNA probe may include plague diagnosis and pathogenesis research.

  13. [The prevention measures of plague in Hebei from 1946 to 1948].

    Science.gov (United States)

    Jia, Ge

    2010-05-01

    The plague was seriously occurred in Hebei from 1946 to 1948, which had a great impact on the local social economy and people's life. The public health system was established by the government, and people were instructed about the knowledge of health consciousness and life habits for controlling effectively the plague. The measures of giving medicine freely and social assistance were taken for preventing the plague in the folk. Thus, the plague was controlled in a short time. However, the effect of prevention was limited by the objective conditions. The color of western medicine was showed from these measures, and the "modernity" of the system at that time was indicated. PMID:21029708

  14. The plague of Athens: an ancient act of bioterrorism?

    Science.gov (United States)

    Papagrigorakis, Manolis J; Synodinos, Philippos N; Stathi, Angeliki; Skevaki, Chrysanthi L; Zachariadou, Levantia

    2013-09-01

    Recent data implicate Salmonella enterica serovar Typhi as a causative pathogen of the Plague of Athens during the Peloponnesian War (430-426 bc). According to Thucydides, the sudden outbreak of the disease may link to poisoning of the water reservoirs by the Spartans. The siege of a city was aimed at exhausting the supplies of a population, which often led to the outbreak and spread of epidemics. Poisoning of the water reservoirs of a besieged city as an act of bioterrorism would probably shorten the necessary time for such conditions to appear.

  15. Origin of the old testament plagues: explications and implications.

    Science.gov (United States)

    Ehrenkranz, N Joel; Sampson, Deborah A

    2008-03-01

    Analyses of past disasters may supply insights to mitigate the impact of recurrences. In this context, we offer a unifying causative theory of Old Testament plagues, which has present day public health implications. We propose the root cause to have been an aberrant El Niño-Southern Oscillation teleconnection that brought unseasonable and progressive climate warming along the ancient Mediterranean littoral, including the coast of biblical Egypt, which, in turn, initiated the serial catastrophes of biblical sequence - in particular arthropod-borne and arthropod-caused diseases. Located beyond the boundary of focal climate change, inland Goshen would not have been similarly affected. Implicit in this analysis is a framework to consider a possibility of present day recurrence of similar catastrophes and their impact upon essential public services.

  16. Cellulose acetate as solid phase in ELISA for plague

    Directory of Open Access Journals (Sweden)

    Barbosa AD

    2000-01-01

    Full Text Available Antigen from Yersinia pestis was adsorbed on cellulose acetate discs (0.5 cm of diameter which were obtained from dialysis membrane by using a paper punch. ELISA for human plague diagnosis was carried out employing this matrix and was capable to detect amount of 1.3 µg of antigen, 3,200 times diluted positive serum using human anti-IgG conjugate diluted 1:4,000. No relevant antigen lixiviation from the cellulose acetate was observed even after washing the discs 15 times. The discs were impregnated by the coloured products from the ELISA development allowing its use in dot-ELISA. Furthermore, cellulose acetate showed a better performance than the conventional PVC plates.

  17. [Transylvanian refugees and the plague in 1708-1709].

    Science.gov (United States)

    Kis, D

    1993-01-01

    Owing to the overwhelming military power of the Habsburg forces Transylvanian sympathizers fled twice to Hungary during the Rákóczi uprising (1704-1711): first in 1704-1706 and then in 1707-1711. In the autumn of 1707 they numbered as much as ten thousand people, and according to the decrees of the diet at Kisvárda, they were settled down in smaller units in around Szabolcs, Szatmár, Bereg, Ung, Ugocsa and Máramaros counties. Though always short of money, the leaders of the ukprising created a system that satisfied the basic needs of these refugees. By the end of the rebellion, nevertheless, as the territory controlled by Rákóczi's armies decreased considerably, the refugees were forced to move on and on, which certainly led to a corruption of their food supplies, accommodation and hygienic conditions. The worst among all came with the plague. The author examines the effects of the epidemic and the counter-measures taken by the individual and the authorities of the uprising. Kis has consulted the main Hungarian books of that age that referred to black death (among others Anna Zay's Herbarium [1719], Samuel Köleséri's Pestis Daicae, György Komáromi Csipkés's Pestis pestise, Ferenc Pápai Páriz's Pax Corporis and A [estos betegség etc., and Máté Tsanaki's A Döghalálról, etc.), as well as many archival papers (the correspondence of Count Sándor Károlyi with his wife Krisztina Barkóczy, thos of General Bercsényi to his wife and Prince Rákóczi, and some doctors' reports, etc.). His main source, however, is Zsigmond Szaniszló's diary. Szaniszló was a former fobiró (chief-sheriff) of the Transsylvanian Torda city, an Anti-Trinitarian stronghold, and remained a leader of his people during the emigration. According to his notes, which the author has compared with the data given by the others, there were hardly any measures taken against plague in this community. Although Szaniszló gives detailed descriptions about the everyday life of the

  18. A bibliography of literature pertaining to plague (Yersinia pestis)

    Science.gov (United States)

    Ellison, Laura E.; Frank, Megan K. Eberhardt

    2011-01-01

    Plague is an acute and often fatal zoonotic disease caused by the bacterium Yersinia pestis. Y. pestis mainly cycles between small mammals and their fleas; however, it has the potential to infect humans and frequently causes fatalities if left untreated. It is often considered a disease of the past; however, since the late 1800s, plagueis geographic range has expanded greatly, posing new threats in previously unaffected regions of the world, including the Western United States. A literature search was conducted using Internet resources and databases. The keywords chosen for the searches included plague, Yersinia pestis, management, control, wildlife, prairie dogs, fleas, North America, and mammals. Keywords were used alone or in combination with the other terms. Although this search pertains mostly to North America, citations were included from the international research community, as well. Databases and search engines used included Google (http://www.google.com), Google Scholar (http://scholar.google.com), SciVerse Scopus (http://www.scopus.com), ISI Web of Knowledge (http://apps.isiknowledge.com), and the USGS Library's Digital Desktop (http://library.usgs.gov). The literature-cited sections of manuscripts obtained from keyword searches were cross-referenced to identify additional citations or gray literature that was missed by the Internet search engines. This Open-File Report, published as an Internet-accessible bibliography, is intended to be periodically updated with new citations or older references that may have been missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the audience (users) think need to be included.

  19. [PLAGUE IN PALERMO IN 1575 AND SOCIAL CONTROL].

    Science.gov (United States)

    Malta, Renato; Salerno, Alfredo

    2015-01-01

    The work moves from the low mortality of the plague of Palermo in 1575 - 1576 in comparison to similar outbreaks and contemporary analysis of the activity of Ingrassia, a man that the city government had wanted at his side. The extraordinary health interventions, including those to favor of the predisposition of health building to isolation, gears for a more wide-ranging than the traditional one. The isolation adopted by Ingrassia wasn't a novelty because it was already in use half a century earlier, as the Previdelli wrote. We assume that the population in crisis, hungry and out of work for the huge military expenditure of king Philip II, would have prompted the City government to use the outbreak for the purposes of control>. At the same goal always answered in the sixteenth century the establishment of the parish, created to divide the territory in order to guide and control the practice of the faith of the people. Ingrassia, a man next to political power, which in turn welded with the spiritual power in order to implement the Catholic Counter-Reformation, justified the coercive initiatives towards the population. The practice of medicine, as still happens today, is affected by the conditions of the policy, raising one of the fundamental principles of bioethics, the question ofthe independence ofthe doctor: a physician divided by the duty to represent the legitimate interests of the patient and those of political power, perhaps not always shared. It is a new interpretation of the activity of Ingrassia and his results than the plague. PMID:26946814

  20. Plague in Egypt: Disease biology, history and contemporary analysis: A minireview

    OpenAIRE

    Lotfy, Wael M.

    2013-01-01

    Plague is a zoonotic disease with a high mortality rate in humans. Unfortunately, it is still endemic in some parts of the world. Also, natural foci of the disease are still found in some countries. Thus, there may be a risk of global plague re-emergence. This work reviews plague biology, history of major outbreaks, and threats of disease re-emergence in Egypt. Based on the suspected presence of potential natural foci in the country, the global climate change, and the threat posed by some nei...

  1. Plague in Egypt: Disease biology, history and contemporary analysis: A minireview

    Directory of Open Access Journals (Sweden)

    Wael M. Lotfy

    2015-07-01

    Full Text Available Plague is a zoonotic disease with a high mortality rate in humans. Unfortunately, it is still endemic in some parts of the world. Also, natural foci of the disease are still found in some countries. Thus, there may be a risk of global plague re-emergence. This work reviews plague biology, history of major outbreaks, and threats of disease re-emergence in Egypt. Based on the suspected presence of potential natural foci in the country, the global climate change, and the threat posed by some neighbouring countries disease re-emergence in Egypt should not be excluded. The country is in need for implementation of some preventive measures.

  2. Demographic and spatio-temporal variation in human plague at a persistent focus in Tanzania

    DEFF Research Database (Denmark)

    Davis, S; Makundi, R H; Machang'u, R S;

    2006-01-01

    Human plague in the Western Usambara Mountains in Tanzania has been a public health problem since the first outbreak in 1980. The wildlife reservoir is unknown and eradication measures that have proved effective elsewhere in Tanzania appear to fail in this region. We use census data from 2002...... for the remainder of the focus. The likelihood of becoming infected with plague is highest between the ages of 5 and 19 and lowest for adult men. This was most clear in the ward encompassing the three high-incidence villages where the risk of plague among children aged 10-14 was 2.2 times higher than for adults...

  3. [The Antonine plague: A global pestilence in the II century d.C].

    Science.gov (United States)

    Sáez, Andrés

    2016-04-01

    The Antonine plague was the first plague affecting globally the Western world. It affected all aspects of life of mankind in the Roman Empire: economics, politics, religion and the culture. The especialists set the mortality rate in the 10% of the population. On the other hand the existence of unified Roman Empire from culturally and territorially helped to spreading the plague as it could similarly occur in our society in a similar pandemic. In conclusion, it is argued that the epidemic was global in a sense of the geographical extension and the effects this had on the population. PMID:27314999

  4. [Mechanisms of power in disease: the case of the novel "The Plague" by Albert Camus].

    Science.gov (United States)

    Hernández-Mansilla, José Miguel

    2009-01-01

    This paper explores the elements of power that can be found in an epidemic like the plague. To undertake this task we first studied, the form of containment of the plague from a historical perspective and then, compare them with those described by Camus in his novel The Plague. We also studied the experience of sin among humans in an effort to determine divine power. This last point explores the fear of being touched during an epidemic and how this is overcome by the innate feeling of love among men. Finally in the novel, this is illustrated by the love of Orpheus for Eurydice.

  5. Epidemiology of Human Plague in the United States, 1900–2012

    Centers for Disease Control (CDC) Podcasts

    2015-02-23

    Dr. Kiersten Kugeler discusses the Epidemiology of Human Plague in the United States.  Created: 2/23/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/23/2015.

  6. Humoral and Cellular Immune Responses to Yersinia pestis Infection in Long-Term Recovered Plague Patients

    OpenAIRE

    Li, Bei; Du, Chunhong; Zhou, Lei; Bi, Yujing; Wang, Xiaoyi; Wen, Li; Guo, Zhaobiao; Song, Zhizhong; Yang, Ruifu

    2012-01-01

    Plague is one of the most dangerous diseases and is caused by Yersinia pestis. Effective vaccine development requires understanding of immune protective mechanisms against the bacterium in humans. In this study, the humoral and memory cellular immune responses in plague patients (n = 65) recovered from Y. pestis infection during the past 16 years were investigated using a protein microarray and an enzyme-linked immunosorbent spot assay (ELISpot). The seroprevalence to the F1 antigen in all re...

  7. [The North African plague and Charles Nicolle's theory of infectious diseases].

    OpenAIRE

    Ben, Néfissa Kmar; Moulin, Anne Marie

    2010-01-01

    Many infectious diseases were described in North Africa in 18th-19th centuries by European travellers. Most of them were allegedly imported by new migrant populations coming from sub-Saharan, European or Middle East countries. Plague outbreaks have been described since the Black Death as diseases of the Mediterranean harbours. Charles Nicolle and his collaborators at the Pasteur Institute were witnesses to the extinction of plague and typhus fever in Tunisia. Both could be considered as endem...

  8. Phylogenetic Analysis of Entomoparasitic Nematodes, Potential Control Agents of Flea Populations in Natural Foci of Plague

    OpenAIRE

    E. I. Koshel; Aleshin, V. V.; Eroshenko, G. A.; Kutyrev, V. V.

    2014-01-01

    Entomoparasitic nematodes are natural control agents for many insect pests, including fleas that transmit Yersinia pestis, a causative agent of plague, in the natural foci of this extremely dangerous zoonosis. We examined the flea samples from the Volga-Ural natural focus of plague for their infestation with nematodes. Among the six flea species feeding on different rodent hosts (Citellus pygmaeus, Microtus socialis, and Allactaga major), the rate of infestation varied from 0 to 21%. The prop...

  9. [Epizootological assessment of the possibilities of importing plague from Vietnam to Russia].

    Science.gov (United States)

    Bazanova, L P; Maramovich, A S; Nikitin, A Ia; Okunev, L P; Innokent'eva, T I; Kosilko, S A; Voronova, G A

    2011-01-01

    To assess whether the plague microbe with vectors or carriers can be imported from Vietnam to Russia, the authors consider the specific features of pathogen circulation in this country's biotopes varying in anthropogenic transformation. The idea that there were natural foci of plague in Vietnam dominated until the late 1990s. The small rat Rattus exulans that inhabits open stations and ensures a parasitic contact with the synanthropic representatives of the fauna was considered to be a major carrier. The recent years have provided conclusive proofs that plague foci are absent in Vietnam wild nature. Anthropurgic foci develop in the network of localities whose conditions are favorable to the existence of synanthropic rodents and the fleas Xenopsylla cheopis. Cases of the plague pathogen, FI antigen and its antibodies being detected in wild mammals are due to their parasitic contacts with synanthropic rats in the agrocultural area around the localities with running epizootias. These contacts are provided by X.cheopis only. Since 2003, there have been no reports on the incidence of human plague or its pathogen isolation from environmental objects in Vietnam. However, all conditions and prerequisites for the formation ofanthropurgic plague foci remain in this country. Further epizootological monitoring is required for appropriate services to rapidly and adequately respond if the epizootological or epidemiological situation of this infection changes. PMID:21797070

  10. The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs

    Science.gov (United States)

    Busch, Joseph D.; Van Andel, Roger; Stone, Nathan E.; Cobble, Kacy R.; Nottingham, Roxanne; Lee, Judy; VerSteeg, Michael; Corcoran, Jeff; Cordova, Jennifer; Van Pelt, William E.; Shuey, Megan M.; Foster, Jeffrey T.; Schupp, James M.; Beckstrom-Sternberg, Stephen; Beckstrom-Sternberg, James; Keim, Paul; Smith, Susan; Rodriguez-Ramos, Julia; Williamson, Judy L.; Rocke, Tonie E.; Wagner, David M.

    2013-01-01

    Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been severely affected by Y. pestis. To examine potential mechanisms accounting for survival in the AV colony, we conducted a laboratory Y. pestis challenge experiment on 60 wild-caught prairie dogs from AV and from a nearby, large colony with frequent past outbreaks of plague, Espee (n = 30 per colony). Test animals were challenged subcutaneously with the fully virulent Y. pestis strain CO92 at three doses: 50, 5,000, and 50,000 colony-forming units (cfu); this range is lethal in black-tailed prairie dogs (Cynomys ludovicianus). Contrary to our expectations, only 40% of the animals died. Although mortality trended higher in the Espee colony (50%) compared with AV (30%), the differences among infectious doses were not statistically significant. Only 39% of the survivors developed moderate to high antibody levels to Y. pestis, indicating that mechanisms other than humoral immunity are important in resistance to plague. The ratio of neutrophils to lymphocytes was not correlated with plague survival in this study. However, several immune proteins with roles in innate immunity (VCAM-1, CXCL-1, and vWF) were upregulated during plague infection and warrant further inquiry into their role for protection against this disease. These results suggest plague resistance exists in wild populations of the Gunnison's prairie dog and provide important directions for future studies.

  11. Are local plague endemicity and ecological characteristics of vectors and reservoirs related? A case study in north-east Tanzania

    Institute of Scientific and Technical Information of China (English)

    Anne LAUDISOIT; Simon NEERINCKX; Rhodes H.MAKUNDI; Herwig LEIRS; Boris R.KRASNOV

    2009-01-01

    The pattern of plague endemicity in Tanzania is characterized by continuous re-appearance of the disease in some locations, while in other neighbouring villages the disease has never or seldom been observed. To understand the reasons for this pattern, we studied small mammal and flea species composition, diversity and relative abundances in two plague-endemic and two plague-free locations. We asked (a) whether fleas more abundant in plague-endemic locations differ in their characteristic abundance and the degree of their host specificity from fleas more abundant in plague-free locations and (b) whether hosts most abundant in plagne-endemic locations differ in the diversity of their flea assemblages from hosts most abundant in plague-free locations. We characterized (a) each host species by species richness and degree of taxonomic relatedness of its flea assemblages and (b) each flea species by its mean abundance and size, and degree of taxonomic relatedness of its host spectrum and compared their relative abundances between locations. No significant difference between plague-endemic and plague-free locations in either host density or any variable related to flea abundance or diversity was found. However, there was marginally significant effect of taxonomic distinctness of a flea assemblage harboured by a host on its probability to be more abundant in either plague-endemic or plague-free locations. Furthermore, hosts more abundant in plague-endemic locations tended to harbeur closely-related fleas. Finally, while opportunistic and specialist fleas were equally distributed in both sets of locations, fleas exploiting distantly-related hosts were found mainly in plague-free locations during the rainy season. We suggest that the observed patterns might arise due to seasonal and spatial differences in local microclimatic conditions and landscape connectivity.

  12. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-02-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  13. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides.

    Directory of Open Access Journals (Sweden)

    Adélaïde Miarinjara

    2016-02-01

    Full Text Available Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines. Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur. Only one insecticide (dieldrin was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar.

  14. Current Perspectives on Plague Vector Control in Madagascar: Susceptibility Status of Xenopsylla cheopis to 12 Insecticides

    Science.gov (United States)

    Miarinjara, Adélaïde; Boyer, Sébastien

    2016-01-01

    Plague is a rodent disease transmissible to humans by infected flea bites, and Madagascar is one of the countries with the highest plague incidence in the world. This study reports the susceptibility of the main plague vector Xenopsylla cheopis to 12 different insecticides belonging to 4 insecticide families (carbamates, organophosphates, pyrethroids and organochlorines). Eight populations from different geographical regions of Madagascar previously resistant to deltamethrin were tested with a World Health Organization standard bioassay. Insecticide susceptibility varied amongst populations, but all of them were resistant to six insecticides belonging to pyrethroid and carbamate insecticides (alphacypermethrin, lambdacyhalothrin, etofenprox, deltamethrin, bendiocarb and propoxur). Only one insecticide (dieldrin) was an efficient pulicide for all flea populations. Cross resistances were suspected. This study proposes at least three alternative insecticides (malathion, fenitrothion and cyfluthrin) to replace deltamethrin during plague epidemic responses, but the most efficient insecticide may be different for each population studied. We highlight the importance of continuous insecticide susceptibility surveillance in the areas of high plague risk in Madagascar. PMID:26844772

  15. Two medieval plague treatises and their afterlife in early modern England.

    Science.gov (United States)

    Keiser, George R

    2003-07-01

    This study of an adaptation of the popular John of Burgundy plague treatise by Thomas Moulton, a Dominican friar, ca. 1475, and a translation of the so-called Canutus plague treatise by Thomas Paynell, printed 1534, shows how the medieval traditions they represent were carried forward, well into the sixteenth century, and also subjected to change in light of religious, moral, and medical concerns of early modern England. The former had a long life in print, ca. 1530-1580, whereas Paynell's translation exists in one printed version. Moulton's adaptation differs from its original and from the Canutus treatise in putting great emphasis on the idea that onsets of plague were acts of divine retribution for human sinfulness. In this respect, Moulton reshaped the tradition of the medieval plague treatise and anticipated the religious and social construction of plague that would take shape in the first half of the sixteenth century. Its long history in print indicates that Moulton's treatise expressed the spirit of that construction and probably influenced the construction as well. The contrasting histories of the two treatises attest not only to the dramatic change brought about by religious and social forces in the sixteenth century, but to a growing recognition of the value of the printing press for disseminating medical information-in forms that served social and ideological ends.

  16. Evidence of Yersinia pestis DNA from fleas in an endemic plague area of Zambia

    Directory of Open Access Journals (Sweden)

    Hang'ombe Bernard M

    2012-01-01

    Full Text Available Abstract Background Yersinia pestis is a bacterium that causes plague which infects a variety of mammals throughout the world. The disease is usually transmitted among wild rodents through a flea vector. The sources and routes of transmission of plague are poorly researched in Africa, yet remains a concern in several sub-Saharan countries. In Zambia, the disease has been reported on annual basis with up to 20 cases per year, without investigating animal reservoirs or vectors that may be responsible in the maintenance and propagation of the bacterium. In this study, we undertook plague surveillance by using PCR amplification of the plasminogen activator gene in fleas. Findings Xenopsylla species of fleas were collected from 83 rodents trapped in a plague endemic area of Zambia. Of these rodents 5 had fleas positive (6.02% for Y. pestis plasminogen activator gene. All the Y. pestis positive rodents were gerbils. Conclusions We conclude that fleas may be responsible in the transmission of Y. pestis and that PCR may provide means of plague surveillance in the endemic areas of Zambia.

  17. Seroprevalence of hantavirus and Yersinia pestis antibodies in professionals from the Plague Control Program

    Directory of Open Access Journals (Sweden)

    Erika de Cassia Vieira da Costa

    2013-07-01

    Full Text Available Introduction Professionals who handle rodents in the field and in the laboratory are at risk of infection by the microorganisms harbored by these animals. Methods Serum samples from professionals involved in rodent and Yersinia pestis handling in field or laboratory work were analyzed to determine hantavirus and plague seroprevalence and to establish a relationship between these activities and reports of illnesses. Results Two individuals had antibodies against hantavirus, and two harbored antibodies against the plague; none of the individuals had experienced an illness related to their duties. Conclusions These results confirm the risks of hantavirus- and plague-related field and laboratory activities and the importance of protective measures for such work.

  18. Diagnosis of plague and identification of virulence markers in Yersinia pestis by multiplex-PCR

    Directory of Open Access Journals (Sweden)

    LEAL Nilma C.

    1999-01-01

    Full Text Available We have developed a procedure for the rapid diagnosis of plague that also allows the identification of prominent virulence markers of Y. pestis strains. This procedure is based upon the use of a single polymerase chain reaction with multiple pairs of primers directed at genes present in the three virulence plasmids as well as in the chromosomal pathogenicity island of the bacterium. The technique allowed the discrimination of strains which lacked one or more of the known pathogenic loci, using as template total DNA obtained from bacterial cultures and from simulated blood cultures containing diluted concentration of bacteria. It also proved effective in confirming the disease in a blood culture from a plague suspected patient. As the results are obtained in a few hours this technique will be useful in the methodology of the Plague Control Program.

  19. Post-epizootic surveys of waterfowl for duck plague (duck virus enteritis)

    Science.gov (United States)

    Brand, C.J.; Docherty, D.E.

    1988-01-01

    Surviving birds from nine duck plague outbreaks in urban and confined waterfowl were sampled for duck plague (DP) virus and DP antibody during 1979-86. Duck plague virus was found in combined oral and cloacal swabs of birds from three outbreaks, and DP-neutralizing antibody was demonstrated in some birds from all nine outbreaks. Greater prevalence of DP antibody and higher titers were found in survivors from confined populations than from free-flying urban populations. Free-flying waterfowl from within 52 km of four DP outbreak sites were also sampled; virus was not found in any birds, but DP antibody was found in urban waterfowl in the vicinity of an outbreak in Potterville, Michigan. No evidence of exposure to or shedding of DP virus in migratory waterfowl was found in two regions where DP appears enzootic in urban and confined waterfowl (Eastern Shore of Maryland and the vicinity of Sacramento, California).

  20. Findings of bacterial microflora in piglets infected with conventional swine plague

    Directory of Open Access Journals (Sweden)

    Prodanov Jasna

    2002-01-01

    Full Text Available Piglets infected with the conventional swine plague virus as a result of secondary bacterial infections sometimes show an insufficiently clear clinical and pathoanatomical picture, which is why the very procedure of diagnosis is complex and the final diagnosis unreliable. That is why these investigations were aimed at examining the presence of bacterial microflora in diseased and dead pilgets which were found to have the viral antigen for CSP using the fluorescent antibody technique, in cases where the pathomorphological finding was not characteristic for conventional swine plague. Autopsies of dead piglets most often showed changes in the digestive tract and lungs, with resulting technopathy and diseases of infective nature. Such findings on knowledge of a present bacterial microflora are especially important in cases when conventional swine plague is controlled on farms and an announcement that the disease has been contained is in the offing.

  1. 圣经中的鼠疫及纪年%Plague and Its Time in Bible

    Institute of Scientific and Technical Information of China (English)

    马学博

    2015-01-01

    圣经记载了最早一次鼠疫流行,西方学者为此长期争论不休,主要集中在临床症状的译名、宿主动物黑鼠是否存在等,而发生鼠疫流行的年代则语焉不详。现据文献研究及考古发掘证据,试图阐释“非利士人鼠疫”的可信性,提出相对准确的纪年约为公元前1050年,并且涉及了旧约时代中东鼠疫自然疫源地及鼠疫流行史研究与鼠疫实验科学研究关系问题。%The first plague epidemic was recorded in the Bible. Western scholars debated about it for a long time, focusing mainly in the translation of clinical symptoms, the presence of host animal rattus, and so on. However, the time of plague epidemic was vague. According to the evidence of literature research and archaeological excavations, the article attempted to explain the credibility of 'Philistine plague', and proposed that the relatively accurate time of plague epidemic is 1050 BC. At the same time, the article involved in the Old Testament times' natural foci of plague in the Near East, and the relation of study of the history of the plague epidemic and experimental scientific research.

  2. Use of Rhodamine B as a biomarker for oral plague vaccination of prairie dogs

    Science.gov (United States)

    Fernandez, Julia Rodriguez-Ramos; Rocke, Tonie E.

    2011-01-01

    Oral vaccination against Yersinia pestis could provide a feasible approach for controlling plague in prairie dogs (Cynomys spp.) for conservation and public health purposes. Biomarkers are useful in wildlife vaccination programs to demonstrate exposure to vaccine baits. Rhodamine B (RB) was tested as a potential biomarker for oral plague vaccination because it allows nonlethal sampling of animals through hair, blood, and feces. We found that RB is an appropriate marker for bait uptake studies of C. ludovicianus) when used at concentrations 10 mg RB per kg target animal mass. Whiskers with follicles provided the best sample for RB detection.

  3. Spatial analysis and identification of high risk plague regions in Pakistan based on associated rodent species distribution.

    Science.gov (United States)

    Shabbir, Madiha; Aleem, Maha; Javed, Sundus; Wagner, David M; Keim, Paul S; Eqani, Syed Ali Musstjab Akbar Shah; Bokhari, Habib

    2016-01-01

    Plague, caused by Yersinia pestitis, is an infectious bacterial disease that has a high fatality rate if untreated. Rodents are plague reservoirs and play an important role in disease spread. Plague cases have been reported extensively since the second pandemic from the 14th century in countries sharing borders with Pakistan, such as China and India, as well as nearby countries including Russia and central Asia. Despite being centrally located in a plague-infested geographical zone, there has been no plague incidence reported from Pakistan. This study aims to pinpoint some of the potentially important aspects of the disease, which have to be considered when assessing potential risk associated with a plague outbreak in Pakistan. In this context, the occurrence and distribution of plague-associated rodent reservoirs in different regions of Pakistan in relation to those found in the neighboring countries were mapped. In addition, the climatic factors that may also influence disease spread by affecting the growth of the bacteria are also discussed. The combined epidemiological and ecological surveillance studies suggest a prevalence of several potential rodent carriers in certain districts with the possibility of a plague outbreak in Pakistan. PMID:27482799

  4. Spatial analysis and identification of high risk plague regions in Pakistan based on associated rodent species distribution.

    Science.gov (United States)

    Shabbir, Madiha; Aleem, Maha; Javed, Sundus; Wagner, David M; Keim, Paul S; Eqani, Syed Ali Musstjab Akbar Shah; Bokhari, Habib

    2016-01-01

    Plague, caused by Yersinia pestitis, is an infectious bacterial disease that has a high fatality rate if untreated. Rodents are plague reservoirs and play an important role in disease spread. Plague cases have been reported extensively since the second pandemic from the 14th century in countries sharing borders with Pakistan, such as China and India, as well as nearby countries including Russia and central Asia. Despite being centrally located in a plague-infested geographical zone, there has been no plague incidence reported from Pakistan. This study aims to pinpoint some of the potentially important aspects of the disease, which have to be considered when assessing potential risk associated with a plague outbreak in Pakistan. In this context, the occurrence and distribution of plague-associated rodent reservoirs in different regions of Pakistan in relation to those found in the neighboring countries were mapped. In addition, the climatic factors that may also influence disease spread by affecting the growth of the bacteria are also discussed. The combined epidemiological and ecological surveillance studies suggest a prevalence of several potential rodent carriers in certain districts with the possibility of a plague outbreak in Pakistan.

  5. 西方小说中的瘟疫题材%Plague Theme in Western Novels

    Institute of Scientific and Technical Information of China (English)

    范蕊; 仵从巨

    2014-01-01

    Plague has an intimate relationship with humans:it not only affects the social process but also has a pro-found impact on people's cultural and spiritual state .The plague is an important theme of literature and many world masterpieces take plague as their background .The plague in the Middle Ages accelerated the Renaissance and the Reformation.Giovanni Boccaccio's Decameron is famous for taking plague as the background .It highlights the value of the Renaissance and the inevitability of Reformation .The 18th-century Enlightenment literature described the world with objective and rational manners .British writer Daniel Defoe's novel A Journal of the Plague Year stressed this tendency .French writer Giono's novel The Horseman on the Roof and the Colombian writer Marquez's Love in the Time of Cholera put plague and love together , the love story dazzling with the plague .In the novel The Plague written by Albert Camus , the plague has a broader symbolism and different choices when people face plague is the expression of existential philosophy .%瘟疫与人类关系密切,不仅影响社会进程还影响人们的文化和精神状态。瘟疫是文学中的重要题材,不少世界名著都以瘟疫为背景,或者直接表现瘟疫。中世纪的瘟疫促进了文艺复兴和宗教改革的出现,意大利作家薄伽丘的《十日谈》就是以瘟疫为背景的名著,突出了文艺复兴时期的价值倾向和宗教改革的必然。18世纪启蒙主义文学以客观理性的态度表现世界,英国作家狄福的《大疫年纪事》则突出表达了这一倾向。法国作家吉奥诺的《屋顶上的骑兵》和哥伦比亚作家马尔克斯的《霍乱时期的爱情》则将瘟疫与爱情同置,爱情故事在瘟疫的映衬下显得光彩夺目。法国存在主义作家加缪的《鼠疫》中,瘟疫具有更广泛的象征意义,面对瘟疫的不同选择突出表达了存在主义的哲学观。

  6. Temporal Progression of Pneumonic Plague in Blood of Nonhuman Primate: A Transcriptomic Analysis.

    Directory of Open Access Journals (Sweden)

    Rasha Hammamieh

    Full Text Available Early identification of impending illness during widespread exposure to a pathogenic agent offers a potential means to initiate treatment during a timeframe when it would be most likely to be effective and has the potential to identify novel therapeutic strategies. The latter could be critical, especially as antibiotic resistance is becoming widespread. In order to examine pre-symptomatic illness, African green monkeys were challenged intranasally with aerosolized Yersinia pestis strain CO92 and blood samples were collected in short intervals from 45 m till 42 h post-exposure. Presenting one of the first genomic investigations of a NHP model challenged by pneumonic plague, whole genome analysis was annotated in silico and validated by qPCR assay. Transcriptomic profiles of blood showed early perturbation with the number of differentially expressed genes increasing until 24 h. By then, Y. pestis had paralyzed the host defense, as suggested by the functional analyses. Early activation of the apoptotic networks possibly facilitated the pathogen to overwhelm the defense mechanisms, despite the activation of the pro-inflammatory mechanism, toll-like receptors and microtubules at the port-of-entry. The overexpressed transcripts encoding an early pro-inflammatory response particularly manifested in active lymphocytes and ubiquitin networks were a potential deviation from the rodent models, which needs further verification. In summary, the present study recognized a pattern of Y. pestis pathogenesis potentially more applicable to the human system. Independent validation using the complementary omics approach with comprehensive evaluation of the organs, such as lungs which showed early bacterial infection, is essential.

  7. Quinto Tiberio Angelerio and New Measures for Controlling Plague in 16th-Centruy Alghero, Sardinia

    Centers for Disease Control (CDC) Podcasts

    2013-10-28

    Reginald Tucker reads an abridged version of the Emerging Infectious Diseases’ historical Review, Quinto Tiberio Angelerio and New Measures for Controlling Plague in 16th -Centruy Alghero, Sardinia.  Created: 10/28/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/30/2013.

  8. Lessons from the History of Quarantine, from Plague to Influenza A

    Centers for Disease Control (CDC) Podcasts

    2013-05-08

    Reginald Tucker reads an abridged version of the Emerging Infectious Diseases’ Historical Review, Lessons from the History of Quarantine, from Plague to Influenza A.  Created: 5/8/2013 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/15/2013.

  9. Pandemic Fear and Literature: Observations from Jack London’s The Scarlet Plague

    Centers for Disease Control (CDC) Podcasts

    2014-11-18

    Sarah Gregory reads an abridged version of the essay, Pandemic Fear and Literature: Observations from Jack London’s The Scarlet Plague.  Created: 11/18/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/20/2014.

  10. REINTRODUCTION OF NOBLE CRAYFISH ASTACUS ASTACUS AFTER CRAYFISH PLAGUE IN NORWAY

    Directory of Open Access Journals (Sweden)

    TAUGBØL T.

    2004-01-01

    Full Text Available The Glomma and Halden watercourses in Norway were hit by crayfish plague in 1987 and 1989. Reintroduction of the noble crayfish started in 1989 in the Glomma and in 1995 in the Halden watercourse. Norway has especially good conditions for reintroduction of the native crayfish after crayfish plague, as there is no alien plague-carrying crayfish species in the country. In the Glomma watercourse, approx. 15 000 adult crayfish and 10 000 juveniles have been stocked while in the Halden watercourse the figures are 19 000 adults and 26 500 juveniles. All stocking sites were previously regarded as very good crayfish localities. Four years after stocking, natural recruitment was recorded at all adult crayfish stocking sites in the Glomma watercourse and at most sites in the Halden watercourse. Current crayfish density is, however, much lower than pre-plague densities even at the sites where population development has been in progress for more than 10 years. Extensive post-stocking movements were recorded among adult crayfish. Some sites seemed more suitable for settling, resulting in a great variation in CPUE between the different test-fishing sites. Juveniles seem more appropriate as stocking material if the goal is to re-establish a population in a particular area, due to their stationary behaviour, which seems to remain as they grow larger.

  11. Transverse--Harris--lines in a skeletal population from the 1711 Danish plague site

    DEFF Research Database (Denmark)

    Fiscella, Gabriela N; Bennike, Pia; Lynnerup, Niels

    2008-01-01

    This study examines the occurrence and distribution of transverse lines in skeletal remains from the Copenhagen site, a plague cemetery dated 1711 AD. A relatively low frequency for evidence of line formation was observed in the individuals comprising the total sample and no transverse lines were...

  12. Protecting Black-Footed Ferrets and Prairie Dogs Against Sylvatic Plague

    Science.gov (United States)

    Rocke, Tonie E.

    2008-01-01

    Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at other federal agencies and the University of Wisconsin, are developing and testing vaccines that can be used to protect black-footed ferrets and prairie dogs against plague. The black-footed ferret is commonly regarded as the most endangered mammal in North America, and sylvatic plague is a major impediment to its recovery. The three prairie dog species (Gunnison's, black-tailed, and white-tailed prairie dogs), upon which the ferret depends for food and whose burrows they use for shelter, have been drastically reduced from historical levels, resulting in the near extinction of the ferret. All three species are considered 'at risk' and have been petitioned for listing as 'threatened' or 'endangered' by the U.S. Fish and Wildlife Service (FWS). Additionally, the Utah prairie dog is listed as threatened and the Mexican prairie dog is considered endangered in Mexico. Like the black-footed ferret, all five prairie dog species are highly susceptible to plague and regularly experience outbreaks with devastating losses. Controlling plague outbreaks in prairie dogs and ferrets is a vital concern for ongoing recovery programs and conservation efforts for both species.

  13. Level of damages and economical threshold, decisive aspects in the integrated management of plagues.

    Directory of Open Access Journals (Sweden)

    Rafael Meneses

    2011-03-01

    Full Text Available The establishment and application of economical levels demand a procedure to find with precision the insects population in a given moment. In the integrated management of plagues is not allowed the idea that any insect which is feeding from a part of plants requires a control action, that is why it is very important to determine the real effect that this insect population causes to the cultivation. Any decrease in the crop, constitutes a real waste of time; but when the economical level is defined, it is included an additional factor which is the measure cost of the plagues control. The determination of damages of levels is very important for economists, farming experts and specialists; while for producers is very significant its implementation with the objective to count with a sustainable and beneficial agriculture.

  14. Early host cell targets of Yersinia pestis during primary pneumonic plague.

    Directory of Open Access Journals (Sweden)

    Roger D Pechous

    Full Text Available Inhalation of Yersinia pestis causes primary pneumonic plague, a highly lethal syndrome with mortality rates approaching 100%. Pneumonic plague progression is biphasic, with an initial pre-inflammatory phase facilitating bacterial growth in the absence of host inflammation, followed by a pro-inflammatory phase marked by extensive neutrophil influx, an inflammatory cytokine storm, and severe tissue destruction. Using a FRET-based probe to quantitate injection of effector proteins by the Y. pestis type III secretion system, we show that these bacteria target alveolar macrophages early during infection of mice, followed by a switch in host cell preference to neutrophils. We also demonstrate that neutrophil influx is unable to limit bacterial growth in the lung and is ultimately responsible for the severe inflammation during the lethal pro-inflammatory phase.

  15. Plague as a mortality factor in Canada lynx (Lynx canadensis) reintroduced to Colorado.

    Science.gov (United States)

    Wild, Margaret A; Shenk, Tanya M; Spraker, Terry R

    2006-07-01

    As part of a species recovery program, 129 Canada lynx (Lynx canadensis) originating from British Columbia, the Yukon, Manitoba, and Quebec, Canada, and Alaska, USA, were reintroduced to southwestern Colorado, USA, from 1999 to 2003. Of 52 lynx mortalities documented by October 2003, six lynx, including a female and her 5-mo-old kitten, had evidence of Yersinia pestis infection as determined by fluorescent antibody test and/or culture. Postmortem findings in these lynx were characterized by pneumonia, ranging from acute suppurative pneumonia, to multifocal necrotizing pneumonia, to fibrinous bronchopneumonia. Histopathologic examination of lung revealed multiple areas of inflammation and consolidation, areas of edema and hemorrhage, and bacteria surrounded by extensive inflammation. Spleens had severe lymphoid depletion and hypocellular red pulp. Lymphadenomegaly was observed in only one plague-affected lynx. We hypothesize that these Canada lynx were exposed to Y. pestis by infected prey, and these are the first reports of plague in this species. PMID:17092896

  16. A survey of North American migratory waterfowl for duck plague (duck virus enteritis) virus

    Science.gov (United States)

    Brand, Christopher J.; Docherty, Douglas E.

    1984-01-01

    A survey of migratory waterfowl for duck plague (DP) virus was conducted in the Mississippi and Central flyways during 1982 and in the Atlantic and Pacific flyways during 1983. Cloacal and pharyngeal swabs were collected from 3,169 migratory waterfowl in these four flyways, principally mallards (Anas platyrhynchos L.), black ducks (Anas rubripes Brewster), and pintails (Anas acuta L). In addition 1,033 birds were sampled from areas of recurrent DP outbreaks among nonmigratory and captive waterfowl, and 590 from Lake Andes National Wildlife Refuge, the site of the only known major DP outbreak in migratory waterfowl. Duck plague virus was not found in any of the samples. Results support the hypothesis that DP is not established in North American migratory waterfowl as an enzootic disease.

  17. Historical Y. pestis Genomes Reveal the European Black Death as the Source of Ancient and Modern Plague Pandemics.

    Science.gov (United States)

    Spyrou, Maria A; Tukhbatova, Rezeda I; Feldman, Michal; Drath, Joanna; Kacki, Sacha; Beltrán de Heredia, Julia; Arnold, Susanne; Sitdikov, Airat G; Castex, Dominique; Wahl, Joachim; Gazimzyanov, Ilgizar R; Nurgaliev, Danis K; Herbig, Alexander; Bos, Kirsten I; Krause, Johannes

    2016-06-01

    Ancient DNA analysis has revealed an involvement of the bacterial pathogen Yersinia pestis in several historical pandemics, including the second plague pandemic (Europe, mid-14(th) century Black Death until the mid-18(th) century AD). Here we present reconstructed Y. pestis genomes from plague victims of the Black Death and two subsequent historical outbreaks spanning Europe and its vicinity, namely Barcelona, Spain (1300-1420 cal AD), Bolgar City, Russia (1362-1400 AD), and Ellwangen, Germany (1485-1627 cal AD). Our results provide support for (1) a single entry of Y. pestis in Europe during the Black Death, (2) a wave of plague that traveled toward Asia to later become the source population for contemporary worldwide epidemics, and (3) the presence of an historical European plague focus involved in post-Black Death outbreaks that is now likely extinct.

  18. Historical Y. pestis Genomes Reveal the European Black Death as the Source of Ancient and Modern Plague Pandemics.

    Science.gov (United States)

    Spyrou, Maria A; Tukhbatova, Rezeda I; Feldman, Michal; Drath, Joanna; Kacki, Sacha; Beltrán de Heredia, Julia; Arnold, Susanne; Sitdikov, Airat G; Castex, Dominique; Wahl, Joachim; Gazimzyanov, Ilgizar R; Nurgaliev, Danis K; Herbig, Alexander; Bos, Kirsten I; Krause, Johannes

    2016-06-01

    Ancient DNA analysis has revealed an involvement of the bacterial pathogen Yersinia pestis in several historical pandemics, including the second plague pandemic (Europe, mid-14(th) century Black Death until the mid-18(th) century AD). Here we present reconstructed Y. pestis genomes from plague victims of the Black Death and two subsequent historical outbreaks spanning Europe and its vicinity, namely Barcelona, Spain (1300-1420 cal AD), Bolgar City, Russia (1362-1400 AD), and Ellwangen, Germany (1485-1627 cal AD). Our results provide support for (1) a single entry of Y. pestis in Europe during the Black Death, (2) a wave of plague that traveled toward Asia to later become the source population for contemporary worldwide epidemics, and (3) the presence of an historical European plague focus involved in post-Black Death outbreaks that is now likely extinct. PMID:27281573

  19. Multiple mechanisms of transmission of the Caribbean coral disease white plague

    Science.gov (United States)

    Clemens, E.; Brandt, M. E.

    2015-12-01

    White plague is one of the most devastating coral diseases in the Caribbean, and yet important aspects of its epidemiology, including how the disease transmits, remain unknown. This study tested potential mechanisms and rates of transmission of white plague in a laboratory setting. Transmission mechanisms including the transport of water, contact with macroalgae, and predation via corallivorous worms and snails were tested on the host species Orbicella annularis. Two of the tested mechanisms were shown to transmit disease: water transport and the corallivorous snail Coralliophila abbreviata. Between these transmission mechanisms, transport of water between a diseased coral and a healthy coral resulted in disease incidence significantly more frequently in exposed healthy corals. Transmission via water transport also occurred more quickly and was associated with higher rates of tissue loss (up to 3.5 cm d-1) than with the corallivorous snail treatment. In addition, water that was in contact with diseased corals but was filtered with a 0.22-μm filter prior to being introduced to apparently healthy corals also resulted in the transmission of disease signs, but at a much lower rate than when water was not filtered. This study has provided important information on the transmission potential of Caribbean white plague disease and highlights the need for a greater understanding of how these processes operate in the natural environment.

  20. Immunization of black-tailed prairie dog against plague through consumption of vaccine-laden baits

    Science.gov (United States)

    Rocke, T.E.; Smith, S.R.; Stinchcomb, D.T.; Osorio, J.E.

    2008-01-01

    Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis and, along with other wild rodents, are significant reservoirs of plague for other wildlife and humans in the western United States. A recombinant raccoon poxvirus, expressing the F1 antigen of Y. pestis, was incorporated into a palatable bait and offered to three groups (n = 18, 19, and 20) of black-tailed prairie dogs (Cynomys ludovicianus) for voluntary consumption, either one, two, or three times, at roughly 3-wk intervals. A control group (n = 19) received baits containing raccoon poxvirus without the inserted antigen. Mean antibody titers to Y. pestis F1 antigen increased significantly in all groups ingesting the vaccine-laden baits, whereas the control group remained negative. Upon challenge with virulent Y. pestis, immunized groups had higher survival rates (38%) than the unimmunized control group (11%). The mean survival time of groups ingesting vaccine-laden baits either two or three times was significantly higher than that of animals ingesting vaccine-laden baits just one time and of animals in the control group. These results show that oral immunization of prairie dogs against plague provides some protection against challenge at dosages that simulate simultaneous delivery of the plague bacterium by numerous (3-10) flea bites. ?? Wildlife Disease Association 2008.

  1. A rapid field test for sylvatic plague exposure in wild animals

    Science.gov (United States)

    Abbott, Rachel C.; Hudak, Robert; Mondesire, Roy; Baeten, Laurie A.; Russell, Robin E.; Rocke, Tonie E.

    2014-01-01

    Plague surveillance is routinely conducted to predict future epizootics in wildlife and exposure risk for humans. The most common surveillance method for sylvatic plague is detection of antibodies to Yersinia pestis F1 capsular antigen in sentinel animals, such as coyotes (Canis latrans). Current serologic tests for Y. pestis, hemagglutination (HA) test and enzyme-linked immunosorbent assay (ELISA), are expensive and labor intensive. To address this need, we developed a complete lateral flow device for the detection of specific antibodies to Y. pestis F1 and V antigens. Our test detected anti-F1 and anti-V antibodies in serum and Nobuto filter paper samples from coyotes, and in serum samples from prairie dogs (Cynomys ludovicianus), lynx (Lynx canadensis), and black-footed ferrets (Mustela nigripes). Comparison of cassette results for anti-F1 and anti-V antibodies with results of ELISA or HA tests showed correlations ranging from 0.68 to 0.98. This device provides an affordable, user-friendly tool that may be useful in plague surveillance programs and as a research tool.

  2. First evidence of crayfish plague agent in populations of the marbled crayfish (Procambarus fallax forma virginalis

    Directory of Open Access Journals (Sweden)

    Keller N.S.

    2014-01-01

    Full Text Available The introduction of non-indigenous species and associated diseases can cause declines in indigenous flora and fauna and threaten local biodiversity. The crayfish plague pathogen (Aphanomyces astaci, carried and transmitted by latent infected North American crayfish, can lead to high mortalities in indigenous European crayfish populations. Although the parthenogenetic marbled crayfish (Procambarus fallax (Hagen, 1870  forma virginalis is common in the aquarium trade and has established wild populations in Europe, its carrier status is still unknown. This study investigated one captive and three established wild-living marbled crayfish populations for an infection with the crayfish plague pathogen applying real-time PCR. We demonstrate that captive, as well as two wild marbled crayfish populations were infected by A. astaci. Although infection status in laboratory kept specimens reached high levels, marbled crayfish showed no obviously plague-related mortality. Furthermore, sequence analysis revealed that captive crayfish carried the A. astaci genotype Pc, which has earlier been isolated from the North American red swamp crayfish (Procambarus clarkii. The results indicate that due to its positive carrier status marbled crayfish poses a greater threat to local biodiversity in Europe than considered until now.

  3. Vector control improves survival of three species of prairie dogs (Cynomys) in areas considered enzootic for plague

    Science.gov (United States)

    Biggins, Dean E.; Godbey, Jerry L.; Gage, Kenneth L.; Carter, Leon G.; Montenieri, John A.

    2010-01-01

    Plague causes periodic epizootics that decimate populations of prairie dogs (PDs) (Cynomys), but the means by which the causative bacterium (Yersinia pestis) persists between epizootics are poorly understood. Plague epizootics in PDs might arise as the result of introductions of Y. pestis from sources outside PD colonies. However, it remains possible that plague persists in PDs during interepizootic periods and is transmitted at low rates among highly susceptible individuals within and between their colonies. If this is true, application of vector control to reduce flea numbers might reduce mortality among PDs. To test whether vector control enhances PD survival in the absence of obvious plague epizootics, we reduced the numbers of fleas (vectors for Y. pestis) 96–98% (1 month posttreatment) on 15 areas involving three species of PDs (Cynomys leucurus, Cynomys parvidens in Utah, and Cynomys ludovicianus in Montana) during 2000–2004 using deltamethrin dust delivered into burrows as a pulicide. Even during years without epizootic plague, PD survival rates at dusted sites were 31–45% higher for adults and 2–34% higher for juveniles compared to survival rates at nondusted sites. Y. pestis was cultured from 49 of the 851 flea pools tested (6882 total fleas) and antibodies against Y. pestis were identified in serum samples from 40 of 2631 PDs. Although other explanations are possible, including transmission of other potentially fatal pathogens by fleas, ticks, or other ectoparasites, our results suggest that plague might be maintained indefinitely in PD populations in the absence of free epizootics and widespread mortality among these animals. If PDs and their fleas support enzootic cycles of plague transmission, there would be important implications for the conservation of these animals and other species.

  4. [Plague in Algeria: about five strains of Yersinia pestis isolated during the outbreak of June 2003].

    Science.gov (United States)

    Lounici, M; Lazri, M; Rahal, K

    2005-02-01

    In this study, we isolated and identified five strains of Yersinia pestis during an epidemic occurred in west of Algeria in June 2003. The bacteriological identification was confirmed by bacteriophage susceptibility. All these strains belonged to the biovar Orientalis (they did not ferment glycerol but did reduce nitrate to nitrite) which caused the current pandemic. The in vitro activities of antimicrobial agents used to treat plague and recommended for prophylaxis, showed that they are active against all strains. The comparison of these strains by plasmid profile analyse demonstrated that all isolates had three plasmids: 110, 70 and 9.5 kb, which are present in Y. pestis strains.

  5. Pneumonic Plague

    Science.gov (United States)

    ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Updates Subscribe Listen Page last reviewed July ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Download page Subscribe to RSS Get email ...

  6. Use of Insecticide Delivery Tubes for Controlling Rodent-Associated Fleas in a Plague Endemic Region of West Nile, Uganda.

    Science.gov (United States)

    Boegler, Karen A; Atiku, Linda A; Mpanga, Joseph Tendo; Clark, Rebecca J; Delorey, Mark J; Gage, Kenneth L; Eisen, Rebecca J

    2014-11-01

    Plague is a primarily flea-borne rodent-associated zoonosis that is often fatal in humans. Our study focused on the plague-endemic West Nile region of Uganda where affordable means for the prevention of human plague are currently lacking. Traditional hut construction and food storage practices hinder rodent exclusion efforts, and emphasize the need for an inexpensive but effective host-targeted approach for controlling fleas within the domestic environment. Here we demonstrate the ability of an insecticide delivery tube that is made from inexpensive locally available materials to reduce fleas on domestic rodents. Unbaited tubes were treated with either an insecticide alone (fipronil) or in conjunction with an insect growth regulator [(S)-methoprene], and placed along natural rodent runways within participant huts. Performance was similar for both treatments throughout the course of the study, and showed significant reductions in the proportion of infested rodents relative to controls for at least 100 d posttreatment.

  7. Phylogenetic Analysis of Entomoparasitic Nematodes, Potential Control Agents of Flea Populations in Natural Foci of Plague

    Directory of Open Access Journals (Sweden)

    E. I. Koshel

    2014-01-01

    Full Text Available Entomoparasitic nematodes are natural control agents for many insect pests, including fleas that transmit Yersinia pestis, a causative agent of plague, in the natural foci of this extremely dangerous zoonosis. We examined the flea samples from the Volga-Ural natural focus of plague for their infestation with nematodes. Among the six flea species feeding on different rodent hosts (Citellus pygmaeus, Microtus socialis, and Allactaga major, the rate of infestation varied from 0 to 21%. The propagation rate of parasitic nematodes in the haemocoel of infected fleas was very high; in some cases, we observed up to 1,000 juveniles per flea specimen. Our study of morphology, life cycle, and rDNA sequences of these parasites revealed that they belong to three distinct species differing in the host specificity. On SSU and LSU rRNA phylogenies, these species representing three genera (Rubzovinema, Psyllotylenchus, and Spilotylenchus, constitute a monophyletic group close to Allantonema and Parasitylenchus, the type genera of the families Allantonematidae and Parasitylenchidae (Nematoda: Tylenchida. We discuss the SSU-ITS1-5.8S-LSU rDNA phylogeny of the Tylenchida with a special emphasis on the suborder Hexatylina.

  8. Blood Meal Identification in Off-Host Cat Fleas (Ctenocephalides felis) from a Plague-Endemic Region of Uganda

    OpenAIRE

    Graham, Christine B.; Borchert, Jeff N.; Black, William C.; ATIKU, LINDA A.; Mpanga, Joseph T; Boegler, Karen A.; Moore, Sean M.; Gage, Kenneth L.; Eisen, Rebecca J.

    2013-01-01

    The cat flea, Ctenocephalides felis, is an inefficient vector of the plague bacterium (Yersinia pestis) and is the predominant off-host flea species in human habitations in the West Nile region, an established plague focus in northwest Uganda. To determine if C. felis might serve as a Y. pestis bridging vector in the West Nile region, we collected on- and off-host fleas from human habitations and used a real-time polymerase chain reaction-based assay to estimate the proportion of off-host C. ...

  9. THE MYTHE NOVEL PLAGUE OF ALBERT CAMUS, ITS INSPIRATION SOURCES AND ITS EVOCATIVE SYMBOLS

    Directory of Open Access Journals (Sweden)

    Fuat BOYACIOĞLU

    2012-06-01

    Full Text Available In different periods, some writers made new comments on the antique classics mhytes by readapting them in accordance with the their period. In the XVIIth the french classic playwriters such as Pierre Corneille and Jean Racine took up again the antique myths treated by the antique writers. These playwriters readapted the antique myths in their works according to the conception of their period. In the XXth the french writers such as Jean Giraudoux, André Gide, Jean-Paul Sartre and Albert Camus interpreted again the antique mythes in their works by making evocations to the events occured in their epoch. Treating and displaying the antique mythes in the theater works is a well known fact, but it is an uncommon fact in the novels. The russian novelist Dostoïevsky, the czeche Franz Kafka, the american novelists Herman Melville and William Faulkner interpreted again some mythes under different aspects in their novels. This style of myth roman caused that the american critic Stock asked the following question: Is it possible to reconcile the symbolism and the naturalism, what is the principal and formal problem? The myth roman gives answer to the question : Do the realism and naturalism giving importance the exterior appearance of the matter and things and the symbolism giving importance to the the invisible aspect of the matter and things come together in the same plane? The novel of Albert Camus, The Plague (La Peste containing both realist –naturalist and symbolist elements constitutes an typical exemple of this myth roman. In this novel, Camus relates how the epidemic disease pestilence not occured in reality according to the historical documents, but fabricated fictively by the writer, besieges the algerian city Oran and causes a chaotic situation to the inhabitants as the enemy army did, in a given date, this is to say, in1940’s and a given space. This pestilence event as epidemic disease evokes symbolically the occupation of France by the

  10. LIVING MICROORGANISM’S STABILYZATION IN BIOMASS BIOTECHNOLOGY AND PLAGUE VACCINE PREPARATION

    Directory of Open Access Journals (Sweden)

    D. A. Budika

    2016-01-01

    Full Text Available Over the years, the production release of the plague vaccine is well developed its technology. The technological cycle of production of the preparation consists of regulated steps, however, despite their effectiveness it is necessary to modernize the manufactoring process, for example, solutions for some of the pressing needs of the customers, in particular, small groups of immunization. Our research has focused on obtaining experimental samples plague vaccine smaller compared to the commercial vaccine, the number of doses per vial prepared in a biomass production unit (ACM-Sh surface by cultivation using all regulated processing steps, except step of combining content two swabs, and then an additional dilution of the cell suspension stabilizer. However, the time information and the subsequent preparation of such a vaccine is excluded us, since biomass is the second flush in quantitative terms is a ready raw material for the preparation of reduced dosage. The benefits of receiving the vaccine reduced the number of doses directly from the biomass of the second flush with the concentration of microbial cells Yersinia pestis EV 20–40 × 109 biotechnology greatly simplify the manufacture of such a preparation. The experimental vaccine series were tested by major regulated parameters: optical concentration, vitality, thermal stability, the loss on drying. In addition, the vaccine was prefabricated with high baseline viability to extreme temperatures (37±1°C for 24 hours to exclude enough viable microbial cells for subsequent stabilization indicator of viability during storage. It should be noted that all the experimental samples preserved viability index not lower regulated (25% during the experiment, in contrast to the commercial preparation. To determine the stability of the formulation during storage (over 3 years was a comparative analysis of the viability of the experimental and commercial lots. To assess post vaccination

  11. [Marcus Aurelius Antonius (121-180AD), philosopher and Roman emperor, and Galen's plague].

    Science.gov (United States)

    Muñoz-Sanz, Agustín

    2012-11-01

    The study of the aetiologies of diseases in Ancient Times is usually a speculative intellectual exercise. When some authors attribute a specific aetiology to an old disease, there is a great risk of committing a methodological error, known as presentism by the modern historiography. The authority of the investigator, more than the weight of the scientific truth, is usually the reason why the diagnosis has remained over the years. The great epidemic of the years 164-165AD and afterwards, could have been smallpox (haemorrhagic form). Claude Galen, the famous doctor, described the symptoms in several books of his great Opera Omnia. For this reason, it is currently known among the scholars as Galen's plague. The epidemic was described for the first time in Seleucia (Mesopotamia). Until now, the actual geographic origin is unknown. We propose here that the beginning might be the kingdom of the old Han dynasty (now the Chinese Popular Republic). The epidemic swept the Roman Empire, from the east to the west, and from the southern to the northern borders. An immediate consequence of the infection was a high morbidity and mortality. In this sense, Galen's epidemic was one of the many factors that caused the fall and destruction of the Roman Empire. On the other hand, there is a general agreement among historians, biographers and researchers that the philosopher emperor Marcus Aurelius Antoninus (121-180AD was affected by the infection in the epidemic wave of 164-165AD. The death of Marcus Aurelius occurred on March 17 in the year 180AD, in Vindobonne, or perhaps Sirminium (near to Vienna). Many authors propose that the cause of the emperor's death was the same epidemic. We consider that it is not possible to demonstrate any of those speculative diagnoses. Finally, the epidemic of 189-190AD, that we have named of Commodus, was probably a different disease to the Galen's plague. There were several kinds of animals affected (anthropozoonoses). In this sense, this infection

  12. A recombinant raccoon poxvirus vaccine expressing both Yersinia pestis F1 and truncated V antigens protects animals against lethal plague.

    Science.gov (United States)

    Rocke, Tonie E.; Kingstad-Bakke, B; Berlier, W; Osorio, J.E.

    2014-01-01

    In previous studies, we demonstrated in mice and prairie dogs that simultaneous administration of two recombinant raccoon poxviruses (rRCN) expressing Yersinia pestis antigens (F1 and V307-a truncated version of the V protein) provided superior protection against plague challenge compared to individual single antigen constructs. To reduce costs of vaccine production and facilitate implementation of a sylvatic plague vaccine (SPV) control program for prairie dogs, a dual antigen construct is more desirable. Here we report the construction and characterization of a novel RCN-vectored vaccine that simultaneously expresses both F1 and V307 antigens. This dual antigen vaccine provided similar levels of protection against plague in both mice and prairie dogs as compared to simultaneous administration of the two single antigen constructs and was also shown to protect mice against an F1 negative strain of Y. pestis.. The equivalent safety, immunogenicity and efficacy profile of the dual RCN-F1/V307 construct warrants further evaluation in field efficacy studies in sylvatic plague endemic areas.

  13. Angels with Nanotech Wings: Magic, Medicine and Technology in Aronofksky's The Fountain, Gibson's The Neuromancer and Slonczewski's Brain Plague

    NARCIS (Netherlands)

    C.M. Lord

    2009-01-01

    Darren Aronofsky's feature film The Fountain (2006), William Gibson's celebrated novel The Neuromancer (1984)and Joan Slonczewski'ls best-seller Brain Plague (2000), all have in common a preoccupation with the neuroscientific secrets of the brain. But more than this, all these works that explore the

  14. Deltamethrin flea-control preserves genetic variability of black-tailed prairie dogs during a plague outbreak

    Science.gov (United States)

    Jones, P.H.; Biggins, D.E.; Eads, D.A.; Eads, S.L.; Britten, H.B.

    2012-01-01

    Genetic variability and structure of nine black-tailed prairie dog (BTPD, Cynomys ludovicianus) colonies were estimated with 15 unlinked microsatellite markers. A plague epizootic occurred between the first and second years of sampling and our study colonies were nearly extirpated with the exception of three colonies in which prairie dog burrows were previously dusted with an insecticide, deltamethrin, used to control fleas (vectors of the causative agent of plague, Yersinia pestis). This situation provided context to compare genetic variability and structure among dusted and non-dusted colonies pre-epizootic, and among the three dusted colonies pre- and post-epizootic. We found no statistical difference in population genetic structures between dusted and non-dusted colonies pre-epizootic. On dusted colonies, gene flow and recent migration rates increased from the first (pre-epizootic) year to the second (post-epizootic) year which suggested dusted colonies were acting as refugia for prairie dogs from surrounding colonies impacted by plague. Indeed, in the dusted colonies, estimated densities of adult prairie dogs (including dispersers), but not juveniles (non-dispersers), increased from the first year to the second year. In addition to preserving BTPDs and many species that depend on them, protecting colonies with deltamethrin or a plague vaccine could be an effective method to preserve genetic variability of prairie dogs. ?? 2011 Springer Science+Business Media B.V.

  15. The use of polyvinyl alcohol glutaraldehyde as solid-phase in ELISA for plague

    Directory of Open Access Journals (Sweden)

    Aureci Maria Araujo

    1996-04-01

    Full Text Available Discs of polyvinyl alcohol cross-linked with glutaraldehyde were synthesized under acid catalysis (H2SO4. Then, the antigen F1 purified from Yersinia pestis was covalently linked to this modified polymer. Afterwards, an enzyme-linked immunosorbent assay (ELISA was established for the diagnosis of plague in rabbit and human. The best conditions for the method were achieved by using 1.3 ¼g of F1 prepared in 0.067 M phosphate buffer, pH 7.2, containing 1 M NaCl (PBS; anti-IgG peroxidase conjugate diluted 6,000 times and as a blocking agent 3% w/v skim milk in PBS. The titration of positive rabbit serum according to this procedure detected antibody concentrations up to 1:12,800 times. The present method, the conventional ELISA and passive haemagglutination assay are compared.

  16. Phage therapy of the white plague-like disease of Favia favus in the Red Sea

    Science.gov (United States)

    Atad, I.; Zvuloni, A.; Loya, Y.; Rosenberg, E.

    2012-09-01

    Coral disease is a major factor in the global decline of coral reefs. At present, there are no known procedures for preventing or treating infectious diseases of corals. Immunization is not possible because corals have a restricted adaptive immune system and antibiotics are neither ecologically safe nor practical in an open system. Thus, we tested phage therapy as an alternative therapeutic method for treating diseased corals. Phage BA3, specific to the coral pathogen Thalassomonas loyana, inhibited the progression of the white plague-like disease and transmission to healthy corals in the Gulf of Aqaba, Red Sea. Only one out of 19 (5 %) of the healthy corals became infected when placed near phage-treated diseased corals, whereas 11 out of 18 (61 %) healthy corals were infected in the no-phage control. This is the first successful treatment for a coral disease in the sea. We posit that phage therapy of certain coral diseases is achievable in situ.

  17. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

    Science.gov (United States)

    Eads, David A; Biggins, Dean E

    2015-08-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. PMID:25817984

  18. Evaluation of systemic insecticides mixed in rodenticide baits for plague vector control

    DEFF Research Database (Denmark)

    Larsen, Kim Søholt; Lodal, Jens

    1997-01-01

    Rodenticide baits containing systemic insecticides were evaluated in the laboratory for their palatability to the house rat Rattus rattus and for their toxicity against the oriental rat flea Xenopsylla cheopis - both animals are important Vectors of plague in Africa. The test bait and a non......-poisonous alternative were given to the rats for four days. The evaluation of the effectiveness was based on mortality and poison bait intake in percent of the total consumption. Different concentrations of technical material and different types of encapsulation of the three insecticides phoxim, fenthion and dimethoate...... were used in the tests. The rodenticide used was 0.005 % bromadiolone. For all three insecticides, a reduced intake of the poisonous bait was observed compared with the test of bromadiolone without insecticide. Based on the acceptance of the baits, the dimethoate encapsulated with beef tallow only...

  19. INVESTIGATING A MURDER THE CASE OF THE JUSTINIANIC PLAGUE IN SCYTHIA MINOR

    Directory of Open Access Journals (Sweden)

    Dragos Mitrofan

    2015-03-01

    Full Text Available The study beforehand applies a logical scheme of analysis over a possible presence of the Justinianic plague in the province of Scythia Minor. Following a logic borrowed from the criminalistics, we tried to apply this scheme in order to see if the theory of presence of the epidemic is viable in the given region. Although we have not come with decisive pieces of evidence, a great deal of research is still necessary in order to confirm or infirm this theory. We therefore aim to open a discussion, considering the problem plausible, for the disease had the means and opportunity to affect the province. As previously stated this study is merely a plan of study that shall be developed in a forthcoming work.

  20. [Control and eradication strategies for classic fowl plague in Germany and the European Union].

    Science.gov (United States)

    Werner, Ortrud; Harder, Timm C

    2006-01-01

    The huge potential economic impact of highly pathogenic avian influenza (HPAI) substantiates specific and rigorous legal regulations worldwide. According to the O.I.E. Terrestrial Animal Health Code fowl plague is a notifiable disease. International trading activities concerning poultry and poultry products originating from countries with active HPAI are rigorously restricted. In EU member states directive 92/40/EEC subsumes measures against fowl plague and has been transferred into German legislation by the "Geflügelpest-Verordnung". These acts specify that vaccination against HPAI is principally prohibited. The aim of all sanctions is the extinction of disease and the eradication of the causative agent. However, HPAI viruses, exclusively belonging to subtypes H5 and H7, can re-emerge de novo from progenitor viruses of low pathogenicity which are perpetuated in the wild bird population. An outbreak of HPAI requires prompt action by a stamping out strategy. Fast and accurate diagnosis, a strict stand-still and the culling of affected flocks are at the basis of success. In areas with a high density of poultry holdings preemptive culling and creation of buffer zones, devoid of susceptible poultry, may be neccessary. In these cases emergency vaccinations can be considered as a supportive measure in order to limit mass culling. Vaccinations on merely prophylactic grounds, not being connected to acute outbreaks, should be avoided beware of selective pressures on the virus leading to antigenic drift and escape of vaccine-induced immunity. Instead, high standard biosecurity measures, particularly limiting direct and indirect contacts with wild birds, should be maintained.

  1. Circumventing Y. pestis Virulence by Early Recruitment of Neutrophils to the Lungs during Pneumonic Plague.

    Directory of Open Access Journals (Sweden)

    Yaron Vagima

    2015-05-01

    Full Text Available Pneumonic plague is a fatal disease caused by Yersinia pestis that is associated with a delayed immune response in the lungs. Because neutrophils are the first immune cells recruited to sites of infection, we investigated the mechanisms responsible for their delayed homing to the lung. During the first 24 hr after pulmonary infection with a fully virulent Y. pestis strain, no significant changes were observed in the lungs in the levels of neutrophils infiltrate, expression of adhesion molecules, or the expression of the major neutrophil chemoattractants keratinocyte cell-derived chemokine (KC, macrophage inflammatory protein 2 (MIP-2 and granulocyte colony stimulating factor (G-CSF. In contrast, early induction of chemokines, rapid neutrophil infiltration and a reduced bacterial burden were observed in the lungs of mice infected with an avirulent Y. pestis strain. In vitro infection of lung-derived cell-lines with a YopJ mutant revealed the involvement of YopJ in the inhibition of chemoattractants expression. However, the recruitment of neutrophils to the lungs of mice infected with the mutant was still delayed and associated with rapid bacterial propagation and mortality. Interestingly, whereas KC, MIP-2 and G-CSF mRNA levels in the lungs were up-regulated early after infection with the mutant, their protein levels remained constant, suggesting that Y. pestis may employ additional mechanisms to suppress early chemoattractants induction in the lung. It therefore seems that prevention of the early influx of neutrophils to the lungs is of major importance for Y. pestis virulence. Indeed, pulmonary instillation of KC and MIP-2 to G-CSF-treated mice infected with Y. pestis led to rapid homing of neutrophils to the lung followed by a reduction in bacterial counts at 24 hr post-infection and improved survival rates. These observations shed new light on the virulence mechanisms of Y. pestis during pneumonic plague, and have implications for the

  2. Plague gives surprises in the first decade of the 21st century in the United States and worldwide.

    Science.gov (United States)

    Butler, Thomas

    2013-10-01

    Plague is an ancient disease caused by the bacterium Yersinia pestis and transmitted by rodent flea bites that continues to surprise us with first-ever events. This review documents plague in human cases in the 1st decade of the 21st century and updates our knowledge of clinical manifestations, transmission during outbreaks, diagnostic testing, antimicrobial treatment, and vaccine development. In the United States, 57 persons were reported to have the disease, of which seven died. Worldwide, 21,725 persons were affected with 1,612 deaths, for a case-fatality rate of 7.4%. The Congo reported more cases than any other country, including two large outbreaks of pneumonic plague, surpassing Madagascar, which had the most cases in the previous decade. Two United States scientists suffered fatal accidental exposures: a wildlife biologist, who carried out an autopsy on a mountain lion in Arizona in 2007, and a geneticist with subclinical hemochromatosis in Chicago, who was handling an avirulent strain of Y. pestis in 2009. Antimicrobial drugs given early after the onset of symptoms prevented many deaths; those recommended for treatment and prophylaxis included gentamicin, doxycycline, and fluoroquinolones, although fluoroquinolones have not been adequately tested in humans. Fleas that do not have their guts blocked by clotted blood meals were shown to be better transmitters of plague than blocked fleas. Under development for protection against bioterrorist use, a subunit vaccine containing F1 and V antigens of Y. pestis was administered to human volunteers eliciting antibodies without any serious side effects. These events, although showing progress, suggest that plague will persist in rodent reservoirs mostly in African countries burdened by poverty and civil unrest, causing death when patients fail to receive prompt antimicrobial treatment. PMID:24043686

  3. Epidemiological investigation of animal plague in Microtus brandti plague foci in China——discovery of Mongolian gerbil plague%我国布氏田鼠型鼠疫疫源地动物鼠疫流行病学调查——发现长爪沙鼠型鼠疫

    Institute of Scientific and Technical Information of China (English)

    范蒙光; 李建云; 尉瑞平; 米景川; 张忠兵; 赵刚

    2014-01-01

    目的 调查2005-2013年我国布氏田鼠型疫源地动物鼠疫流行特征,分析出现布氏田鼠型鼠疫和长爪沙鼠型鼠疫交叉流行的新情况.方法 收集2005-2013年布氏田鼠疫源地分离的135株鼠疫菌,根据我国鼠疫菌生态型的分型方法和标准[《鼠疫自然疫源地及动物鼠疫流行判定标准》(GB 16883-1997),布氏田鼠型鼠疫菌发酵鼠李糖,不发酵阿胶糖,长爪沙鼠型鼠疫菌发酵阿胶糖,不发酵鼠李糖],采用生化及糖醇类酵解试验进行菌型鉴定;收集内蒙古阿巴嘎旗、锡林浩特市、苏尼特左旗、东乌珠穆沁旗和西乌珠穆沁旗5个旗县疾病预防控制中心鼠疫专项调查和监测报告,以及各年度内蒙古鼠疫监测总结资料,分析布氏田鼠型疫源地动物鼠疫流行分布情况.结果 测试的135株菌中,2005-2007年及2010年分离的128株菌发酵阿胶糖,不发酵鼠李糖;2008年分离的7株菌发酵鼠李糖,不发酵阿胶糖.确定2005-2007年、2010年4个年度在阿巴嘎旗、锡林浩特市及西乌珠穆沁旗发现的动物鼠疫为长爪沙鼠型鼠疫,2008年在锡林浩特市和东乌珠穆沁旗发现的动物鼠疫流行是布氏田鼠型鼠疫.结论 2005年阿巴嘎旗、锡林浩特市和西乌珠穆沁旗首次检出长爪沙鼠型鼠疫菌,可确定为新发现的长爪沙鼠型疫源地.而作为布氏田鼠型疫源地的阿巴嘎旗、锡林浩特市、苏尼特左旗、西乌珠穆沁旗和东乌珠穆沁旗中,只有东乌珠穆沁旗单独存在布氏田鼠型疫源地,而其余4个旗县均存在布氏田鼠和长爪沙鼠2种鼠疫类型的疫源地;通过2005年以来发现新的疫情可以看出,此疫源地性质变得复杂,对人类构成了严重的威胁,今后应进一步加强研究和防治工作.%Objective To investigate epidemiological characteristics of animal plague in Microtus brandti plague foci in China from 2005-2013,and to found the reason for cross epidemic of Microtus brandti

  4. The Perfect Burrow, but for What? Identifying Local Habitat Conditions Promoting the Presence of the Host and Vector Species in the Kazakh Plague System.

    Directory of Open Access Journals (Sweden)

    Bethany Levick

    Full Text Available The wildlife plague system in the Pre-Balkhash desert of Kazakhstan has been a subject of study for many years. Much progress has been made in generating a method of predicting outbreaks of the disease (infection by the gram negative bacterium Yersinia pestis but existing methods are not yet accurate enough to inform public health planning. The present study aimed to identify characteristics of individual mammalian host (Rhombomys opimus burrows related to and potentially predictive of the presence of R.opimus and the dominant flea vectors (Xenopsylla spp..Over four seasons, burrow characteristics, their current occupancy status, and flea and tick burden of the occupants were recorded in the field. A second data set was generated of long term occupancy trends by recording the occupancy status of specific burrows over multiple occasions. Generalised linear mixed models were constructed to identify potential burrow properties predictive of either occupancy or flea burden.At the burrow level, it was identified that a burrow being occupied by Rhombomys, and remaining occupied, were both related to the characteristics of the sediment in which the burrow was constructed. The flea burden of Rhombomys in a burrow was found to be related to the tick burden. Further larger scale properties were also identified as being related to both Rhombomys and flea presence, including latitudinal position and the season.Therefore, in advancing our current predictions of plague in Kazakhstan, we must consider the landscape at this local level to increase our accuracy in predicting the dynamics of gerbil and flea populations. Furthermore this demonstrates that in other zoonotic systems, it may be useful to consider the distribution and location of suitable habitat for both host and vector species at this fine scale to accurately predict future epizootics.

  5. [Macro- and microevolution as related to the problem of origin and global expansion of the plague pathogen Yersinia pestis].

    Science.gov (United States)

    Suntsov, V V; Suntsova, N I

    2008-01-01

    The ratio of macro- and microevolutionary processes is considered with reference to the ecological scenario of the origin of the plague pathogen and its subsequent natural and anthropogenic global expansion. The macroevolutionary transformation of the ancestral pseudotuberculosis microbe clone into the initial plague microbe Yersinia pestis tarbagani occurred in Central Asia at the end of the Late Pleistocene by a "vertical" Darwinian way in an inadaptive heterothermal continual intermediate environment--the Mongolian marmot Marmota sibirica-flea Oropsylla silantiewi system--via a sequence of unstable and currently extinct intermediate forms. Its natural geographic expansion on the "oil spot" principle in the postglacial time led to the microevolutionary formation of 20-30 hostal subspecies circulating in populations of the background species of burrowing rodents and pikas in arid areas of Eurasia. The intercontinental spread of the "marmot" and "rat" pathogen subspecies in the past few centuries has been exclusively anthropogenic, with the involvement of synanthropic (ship) rats.

  6. Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan: An object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests.

    Science.gov (United States)

    Wilschut, L I; Addink, E A; Heesterbeek, J A P; Dubyanskiy, V M; Davis, S A; Laudisoit, A; M Begon; Burdelov, L A; Atshabar, B B; de Jong, S M

    2013-08-01

    data set which can be used as input for epidemiological plague models. This is an important step in understanding the dynamics of plague.

  7. Bacterial profiling of White Plague Disease across corals and oceans indicates a conserved and distinct disease microbiome

    OpenAIRE

    Roder, Cornelia; Arif, Chatchanit; Daniels, Camille; Weil, Ernesto; Voolstra, Christian R.

    2014-01-01

    Coral diseases are characterized by microbial community shifts in coral mucus and tissue, but causes and consequences of these changes are vaguely understood due to the complexity and dynamics of coral-associated bacteria. We used 16S rRNA gene microarrays to assay differences in bacterial assemblages of healthy and diseased colonies displaying White Plague Disease (WPD) signs from two closely related Caribbean coral species, Orbicella faveolata and Orbicella franksi. Analysis of differential...

  8. Cloning of Thymidine Kinase Gene of Duck Plague Virus Using Degenerate PCR

    Institute of Scientific and Technical Information of China (English)

    HAN Xian-jie; WANG Jun-wei

    2005-01-01

    The DNA of duck plague virus (DPV) thymidine kinase (TK) gene was cloned and sequenced from a vaccine virus in the study. Degenerate oligonucleotide primers for the consensus site of herpesvirus UL24, TK, and glycoprotein H(gH) gene were used in the polymerase chain reaction (PCR) to amplify DNA product with 3 741-base-pairs (bp) in size. DNA sequence analysis revealed a 1 077-base-pairs (bp) open reading frame (ORF) encoding a 358 amino acid polypeptide homologous to herpesvirus TK proteins. The predicted TK protein shared 31.2, 41.3, 35.7, 37.4, and 28.4% identity with herpes simplex virus typel, equine herpesvirus type 4, Marek's disease virus 2, herpesvirus turkey, and infectious laryngotracheitis virus, respectively. Comparison of the amino acid sequences of other herpesvirus TK proteins showed that these proteins were not conserved on the whole, otherwise the portion of the TK proteins corresponding to the nucleotide binding domain and the nucleoside binding site were highly conserved among herpesvirus. Comparison with the amino acid sequences of the conserved nucleotide and nucleoside binding domains of other eleven herpesvirus TK proteins to the predicted DPV peptide confirmed its identity as the DPV TK protein.

  9. Periodic temperature-associated drought/flood drives locust plagues in China.

    Science.gov (United States)

    Zhang, Zhibin; Cazelles, Bernard; Tian, Huidong; Stige, Leif Christian; Bräuning, Achim; Stenseth, Nils Chr

    2009-03-01

    Global warming is currently of great concern. Yet the ecological effects of low-frequency climate variations remain largely unknown. Recent analyses of interdecadal variability in population abundance of the Oriental migratory locust (Locusta migratoria manilensis) in China have revealed negative associations with temperature and positive associations with Yangtze drought and flood frequencies during the past millennium (AD 957-1956). In order to shed new light on the causal relationships between locust abundance, floods, droughts and temperature in ancient China, we used wavelet analysis to explore how the coherencies between the different variables at different frequencies have been changed during the past millennium. We find consistent in-phase coherencies between locusts and drought/flood frequencies, and out-of-phase coherencies between locusts and temperature and between drought/flood and temperature at period components of 160-170 years. Similar results are obtained when historical data of drought/flood frequencies of the Yangtze Delta region are used, despite flood data showing a weak and somewhat inconsistent association with other factors. We suggest that previously unreported periodic cooling of 160-170-year intervals dominate climatic variability in China through the past millennium, the cooling events promoting locust plagues by enhancing temperature-associated drought/flood events. Our results signify a rare example of possible benign effects of global warming on the regional risk of natural disasters such as flood/drought events and outbreaks of pest insects. PMID:19033144

  10. Cloning and Sequence of Glycoprotein H Gene of Duck Plague Virus

    Institute of Scientific and Technical Information of China (English)

    HAN Xian-jie; WANG Jun-wei; MA Bo

    2006-01-01

    The glycoprotein H (gH) gene homologue of duck plague virus (DPV) was cloned by degenerate polymerase chain reaction (PCR) and sequenced. It was located immediately downstream from the thymidine kinase gene (TK). In addition,the 3'-end of the gene homologue to herpesvirus UL21 was located downstream from the gH gene. DPV gH gene open reading frame (ORF) was 2 505 bp in length and its primary translation product was a polypeptide of 834 amino acids long.It possessed several characteristics of membrane glycoproteins, including an N-terminal hydrophobic signal sequence,an external domain containing eight putative N-linked glycosylation sites, a C-terminal transmembrane domain, and a charged cytoplasmic tail. Comparison with other herpesvirus revealed identities of 20.2, 25.1, 23.0, 23.0, 26.5 and 26.0% with the gH counterparts of the human herpesvirus virus 1 (HSV1), equine herpesvirus 4 (EHV4), bovine herpesvirus 1 (BHV1), pseudorabies virus (PRV), gallid herpesvirus 2 (GHV2) and gallid herpesvirus 3 (GHV3), respectively.

  11. Bacterial profiling of White Plague Disease in a comparative coral species framework.

    Science.gov (United States)

    Roder, Cornelia; Arif, Chatchanit; Bayer, Till; Aranda, Manuel; Daniels, Camille; Shibl, Ahmed; Chavanich, Suchana; Voolstra, Christian R

    2014-01-01

    Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries. PMID:23924783

  12. Sir Charles James Martin MB FRS: Australian serpents and Indian plague, one-hundred years ago.

    Science.gov (United States)

    Hawgood, B J

    1997-07-01

    In 1891 as Demonstrator in Physiology at the University of Sydney, Charles Martin began the first systematic study of the chemical and physiological properties of the venoms of the Australian elapid species, Pseudechis porphyriacus and Notechis scutatus. Two major constituents were detected: a large coagulable protein which was associated with intravascular clotting, and a small proteinaceous molecule, an albumose, associated with neurotoxicity. Martin designed and constructed a high-pressure gelatin membrane ultrafilter for fractionation of venom. His studies indicated that certain physiological actions and clinical symptoms were related to the faster rate of diffusion within the tissue space of a neurotoxic constituent relative to a clotting constituent. Extending this work to toxin-antitoxin relationships, Martin provided evidence that antitoxin was a large molecule with slow diffusibility in tissue and advised the administration of curative serum (including diphtheria antitoxin) by intravenous injection. In 1903, Martin returned to London as Director of the Lister Institute of Preventive Medicine. He was soon involved in the planning of scientific work to be undertaken by the Commission for Investigation of Plague in India as the disease continued to ravage the subcontinent. Detailed epidemiological studies of possible factors involved in the spread of Pasteurella pestis showed, unequivocally, that infected rat fleas were the vector of transmission from rats to humans. PMID:9247999

  13. Profiles in medical courage: Joseph Goldberger, the sharecropper’s plague, science and prejudice

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2012-06-01

    Full Text Available No abstract available. Article truncated at 150 words. “You must accept the truth from whatever source it comes”. -MaimonidesThe Sharecropper’s PlagueIn the early half of the twentieth century a mysterious disease, “the sharecropper’s plague”, reached epidemic proportions in the Southern US (1. Each state decided whether it would recognize and publicly admit the existence of what was then considered an embarrassment. The total number of new annual cases was estimated as about 75,000 in 1915 and about 100,000 throughout the 1920s (2. The disease had a 40% mortality rate, and many survivors with dementia were confined to mental institutions (3. Patients initially presented with symmetrically reddened skin, similar to that produced by a sunburn or poison oak. Later, the dermatitis turned rough and scaly in one or more locations, such as the hands, the tops of the feet, or the ankles, or in a butterfly-shaped distribution across the nose. Disturbances of the digestive tract and the …

  14. Managing prairie dogs by managing plague: a vaccine for the future?

    Science.gov (United States)

    Johnson, Terry B.; Rocke, Tonie E.; Gober, Pete; Van Pelt, Bill E.; Miller, Michael W.; Tripp, Daniel W.; Abbott, Rachel C.; Bergman, David L.

    2014-01-01

    The Black-footed Ferret Recovery Implementation Team Executive Committee is conducting a project to develop,and (hopefully) eventually implement, a plague vaccination program for prairie dogs. The project is a component of the WesternAssociation of Fish and Wildlife Agencies Grasslands Conservation Initiative. An effective, field-worthy vaccine against plaguecould be the biggest breakthrough in recovery efforts for the black-footed ferret since the 1981 rediscovery of wild ferrets nearMeeteetse, Wyoming. If proven efficacious, the vaccine could help agencies and stakeholder cooperators maintain specificpopulations of prairie dogs at robust levels, thus enhancing range-wide conservation of those species, as well recovery of the ferret,while enabling control of other prairie dog populations to resolve site-specific agricultural and human health concerns. The resultsof laboratory and field-testing in the early stages of developing this vaccine are preliminary but mostly encouraging. A plan forbroad-scale application is being developed for possible use when testing has been completed and (if warranted) the vaccine isregistered for governmental use. An overview of all aspects of the project is discussed.

  15. Bacterial profiling of White Plague Disease in a comparative coral species framework.

    KAUST Repository

    Roder, Cornelia

    2014-01-01

    Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries.

  16. Droughts may increase susceptibility of prairie dogs to fleas: Incongruity with hypothesized mechanisms of plague cycles in rodents

    Science.gov (United States)

    Eads, David; Biggins, Dean E.; Long, Dustin H.; Gage, Kenneth L.; Antolin, Michael F.

    2016-01-01

    Plague is a reemerging, rodent-associated zoonosis caused by the flea-borne bacterium Yersinia pestis. As a vector-borne disease, rates of plague transmission may increase when fleas are abundant. Fleas are highly susceptible to desiccation under hot-dry conditions; we posited that their densities decline during droughts. We evaluated this hypothesis with black-tailed prairie dogs (Cynomys ludovicianus) in New Mexico, June–August 2010–2012. Precipitation was relatively plentiful during 2010 and 2012 but scarce during 2011, the driest spring–summer on record for the northeastern grasslands of New Mexico. Unexpectedly, fleas were 200% more abundant in 2011 than in 2010 and 2012. Prairie dogs were in 27% better condition during 2010 and 2012, and they devoted 287% more time to grooming in 2012 than in 2011. During 2012, prairie dogs provided with supplemental food and water were in 23% better condition and carried 40% fewer fleas. Collectively, these results suggest that during dry years, prairie dogs are limited by food and water, and they exhibit weakened defenses against fleas. Long-term data are needed to evaluate the generality of whether droughts increase flea densities and how changes in flea abundance during sequences of dry and wet years might affect plague cycles in mammalian hosts.

  17. Spatial distribution and ecological environment analysis of great gerbil in Xinjiang Plague epidemic foci based on remote sensing

    International Nuclear Information System (INIS)

    Yersinia pestis (Plague bacterium) from great gerbil was isolated in 2005 in Xinjiang Dzungarian Basin, which confirmed the presence of the plague epidemic foci. This study analysed the spatial distribution and suitable habitat of great gerbil based on the monitoring data of great gerbil from Chinese Center for Disease Control and Prevention, as well as the ecological environment elements obtained from remote sensing products. The results showed that: (1) 88.5% (277/313) of great gerbil distributed in the area of elevation between 200 and 600 meters. (2) All the positive points located in the area with a slope of 0–3 degree, and the sunny tendency on aspect was not obvious. (3) All 313 positive points of great gerbil distributed in the area with an average annual temperature from 5 to 11 °C, and 165 points with an average annual temperature from 7 to 9 °C. (4) 72.8% (228/313) of great gerbil survived in the area with an annual precipitation of 120–200mm. (5) The positive points of great gerbil increased correspondingly with the increasing of NDVI value, but there is no positive point when NDVI is higher than 0.521, indicating the suitability of vegetation for great gerbil. This study explored a broad and important application for the monitoring and prevention of plague using remote sensing and geographic information system

  18. A live attenuated strain of Yersinia pestis KIM as a vaccine against plague.

    Science.gov (United States)

    Sun, Wei; Six, David; Kuang, Xiaoying; Roland, Kenneth L; Raetz, Christian R H; Curtiss, Roy

    2011-04-01

    Yersinia pestis, the causative agent of plague, is a potential weapon of bioterrorism. Y. pestis evades the innate immune system by synthesizing tetra-acylated lipid A with poor Toll-like receptor 4 (TLR4)-stimulating activity at 37°C, whereas hexa-acylated lipid A, a potent TLR4 agonist, is made at lower temperatures. Synthesis of Escherichia coli LpxL, which transfers the secondary laurate chain to the 2'-position of lipid A, in Y. pestis results in production of hexa-acylated lipid A at 37°C, leading to significant attenuation of virulence. Previously, we described a Y. pestis vaccine strain in which crp expression is under the control of the arabinose-regulated araC P(BAD) promoter, resulting in a 4-5 log reduction in virulence. To reduce the virulence of the crp promoter mutant further, we introduced E. coli lpxL into the Y. pestis chromosome. The χ10030(pCD1Ap) (ΔlpxP32::P(lpxL)lpxL ΔP(crp21)::TT araC P(BAD)crp) construct likewise produced hexa-acylated lipid A at 37°C and was significantly more attenuated than strains harboring each individual mutation. The LD(50) of the mutant in mice, when administered subcutaneously or intranasally was >10(7)-times and >10(4)-times greater than wild type, respectively. Mice immunized subcutaneously with a single dose of the mutant were completely protected against a subcutaneous challenge of 3.6×10(7) wild-type Y. pestis and significantly protected (80% survival) against a pulmonary challenge of 1.2×10(4) live cells. Intranasal immunization also provided significant protection against challenges by both routes. This mutant is an immunogenic, highly attenuated live Y. pestis construct that merits further development as a vaccine candidate.

  19. Rapid and sensitive detection of Yersinia pestis using amplification of plague diagnostic bacteriophages monitored by real-time PCR.

    Directory of Open Access Journals (Sweden)

    Kirill V Sergueev

    Full Text Available BACKGROUND: Yersinia pestis, the agent of plague, has caused many millions of human deaths and still poses a serious threat to global public health. Timely and reliable detection of such a dangerous pathogen is of critical importance. Lysis by specific bacteriophages remains an essential method of Y. pestis detection and plague diagnostics. METHODOLOGY/PRINCIPAL FINDINGS: The objective of this work was to develop an alternative to conventional phage lysis tests--a rapid and highly sensitive method of indirect detection of live Y. pestis cells based on quantitative real-time PCR (qPCR monitoring of amplification of reporter Y. pestis-specific bacteriophages. Plague diagnostic phages phiA1122 and L-413C were shown to be highly effective diagnostic tools for the detection and identification of Y. pestis by using qPCR with primers specific for phage DNA. The template DNA extraction step that usually precedes qPCR was omitted. phiA1122-specific qPCR enabled the detection of an initial bacterial concentration of 10(3 CFU/ml (equivalent to as few as one Y. pestis cell per 1-microl sample in four hours. L-413C-mediated detection of Y. pestis was less sensitive (up to 100 bacteria per sample but more specific, and thus we propose parallel qPCR for the two phages as a rapid and reliable method of Y. pestis identification. Importantly, phiA1122 propagated in simulated clinical blood specimens containing EDTA and its titer rise was detected by both a standard plating test and qPCR. CONCLUSIONS/SIGNIFICANCE: Thus, we developed a novel assay for detection and identification of Y. pestis using amplification of specific phages monitored by qPCR. The method is simple, rapid, highly sensitive, and specific and allows the detection of only live bacteria.

  20. Assessment of a recombinant F1-V fusion protein vaccine intended to protect Canada lynx (Lynx canadensis) from plague

    Science.gov (United States)

    Wolfe, Lisa L.; Shenk, Tanya M.; Powell, Bradford; Rocke, Tonie E.

    2011-01-01

    As part of an ongoing restoration program in Colorado, USA, we evaluated adverse reactions and seroconversion in captive Canada lynx (Lynx canadensis) after vaccination with a recombinant F1-V fusion protein vaccine against Yersinia pestis, the bacterium that causes plague. Ten adult female lynx received the F1-V vaccine; 10 source- and age-matched lynx remained unvaccinated as controls. All of the vaccinated and control lynx remained apparently healthy throughout the confinement period. We observed no evidence of injection site or systemic reactions to the F1-V vaccine. Among vaccinated lynx, differences in log10 reciprocal antibody titers measured in sera collected before and after vaccination (two doses) ranged from 1.2 to 5.2 for anti-F1 antibodies and from 0.6 to 5.2 for anti-V antibodies; titers in unvaccinated lynx did not change appreciably over the course of confinement prior to release, and thus differences in anti-F1 (P=0.003) and anti-V (P=0.0005) titers were greater among vaccinated lynx than among controls. Although our findings suggest that the F1-V fusion protein vaccine evaluated here is likely to stimulate antibody responses that may help protect Canada lynx from plague, we observed no apparent differences in survival between vaccinated and unvaccinated subject animals. Retrospectively, 22 of 50 (44%; 95% confidence interval 29–59%) unvaccinated lynx captured or recaptured in Colorado during 2000–08 had passive hemagglutination antibody titers >1:16, consistent with exposure to Y. pestis; paired pre- and postrelease titers available for eight of these animals showed titer increases similar in magnitude to those seen in response to vaccination, suggesting at least some lynx may naturally acquire immunity to plague in Colorado habitats.

  1. Bibliometrics and visualized analysis of plague research literature%国内外鼠疫研究文献计量可视化分析

    Institute of Scientific and Technical Information of China (English)

    章欣; 盛立; 刁天喜

    2016-01-01

    Objective By analyzing domestic and foreign papers on plague research with bibliometrics and visualized methods, we explored the current situation research trends and cutting-edge dynamics in order to provide information sup-port for plague research as well as strategies for countering bioterrorism.Methods Based on data sources from SCI and CNKI databases, bibliometrics and visualized methods were adopted,including Pajek,VOSviewer, Bibexcel and Citespace, so as to show the major cutting-edge areas of plague research.Results Comprehensive research analysis showed that the USA is leading in plague research, with some strong related institutions.There is still a gap between China and international community for research.Academy of Military Medical Sciences and other institutions are our main plague research efforts. Conclusion We should strengthen plague research, improve our overall level of plague research to provide the necessary support for effective response to natural epidemics and potential bioterrorism incidents.%目的:通过对国内外鼠疫研究进行文献计量及可视化分析,探索该领域的发展情况、研究趋势及动态前沿,以期为我国的鼠疫相关研究提供信息支持并为应对生物恐怖提供策略思路。方法运用文献计量和可视化分析方法,以SCI和CNKI数据库为数据来源,综合应用Pajek、VOSviewer、Bibexcel、Citespace软件,展示全球鼠疫研究主要领域和前沿。结果鼠疫文献计量可视化分析显示,美国在鼠疫研究领域处于领先地位,相关机构研究实力较强。我国与国际水平还有一定差距,军事医学科学院、中国科学院等机构为我国鼠疫主要研究力量。结论我国应加强鼠疫研究,提高整体实力水平,为有效应对自然疫情以及可能暴发的生物恐怖事件提供保障。

  2. [A study on the taxonomy of soil amoebas from Caspian plague foci based on an analysis of ribosomal operon sequences].

    Science.gov (United States)

    Koshel', E I; Anisimova, L V; Novichkova, L A; Vidiaeva, N A; Guseva, N P; Eroshenko, G A; Kutyrev, V V

    2015-01-01

    The results of a study on the taxonomy and quantitative abundance of free-living amoebas in soil samples from the Russian plague foci of the northwestern Caspian steppe, the Caspian sand, and the Volga-Ural steppe are presented. Amoebas of the Willaertia and Hartmanella genera, as well as representatives of myxomycetes, were isolated from samples. From these, amoebas of the Acanthamoeba genus predominated and could be as abundantas 300000 cells per 1 g of soil. Sequencing of the 18S rRNA gene region showed that Acanthamoeba from the Volga-Ural steppe focus belonged to the A. castellanii species. Phylogenetic analysis confirmed that amoebas from two other Caspian foci belonged to the species of Acanthamoeba spp.

  3. Population differences in host immune factors may influence survival of Gunnison's prairie dogs (Cynomys Gunnisoni) during plague outbreaks

    Science.gov (United States)

    Busch, Joseph D.; Van Andel, Roger; Cordova, Jennifer; Colman, Rebecca E.; Keim, Paul; Rocke, Tonie E.; Leid, Jeff G.; Van Pelt, William E.; Wagner, David M.

    2011-01-01

    Over the past 40 yr, epizootics of plague (Yersinia pestis) in northern Arizona have reduced populations of the Gunnison’s prairie dog (Cynomys gunnisoni), with the exception of a large population found in the Aubrey Valley (AV). To examine potential mechanisms accounting for their survival, we collected prairie dog serum samples in 2005–2006 from AV and a neighboring population near Seligman (SE), Arizona. We quantified gene expression at 58 diverse immune proteins using a multiplexed enzyme-linked immunosorbent assay panel. We found a subset of proteins important in coagulation and inflammation (tissue factor [TF], calbindin [Cal], and thrombopoietin [TPO]) and T-cell responses (CD40L and CD40) that were present in AV at levels two to eight times greater than SE. These results suggest that AV and SE animals might differ in their ability to mount an immune response.

  4. Structural Insights into Ail-Mediated Adhesion in Yersinia pestis

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Satoshi; Lukacik, Petra; Barnard, Travis J.; Noinaj, Nicholas; Felek, Suleyman; Tsang, Tiffany M.; Krukonis, Eric S.; Hinnebusch, B. Joseph; Buchanan, Susan K. (Michigan); (NIH); (Michigan-Med)

    2012-01-30

    Ail is an outer membrane protein from Yersinia pestis that is highly expressed in a rodent model of bubonic plague, making it a good candidate for vaccine development. Ail is important for attaching to host cells and evading host immune responses, facilitating rapid progression of a plague infection. Binding to host cells is important for injection of cytotoxic Yersinia outer proteins. To learn more about how Ail mediates adhesion, we solved two high-resolution crystal structures of Ail, with no ligand bound and in complex with a heparin analog called sucrose octasulfate. We identified multiple adhesion targets, including laminin and heparin, and showed that a 40 kDa domain of laminin called LG4-5 specifically binds to Ail. We also evaluated the contribution of laminin to delivery of Yops to HEp-2 cells. This work constitutes a structural description of how a bacterial outer membrane protein uses a multivalent approach to bind host cells.

  5. Genome-scale reconstruction of the metabolic network in Yersinia pestis, strain 91001

    Energy Technology Data Exchange (ETDEWEB)

    Navid, A; Almaas, E

    2009-01-13

    The gram-negative bacterium Yersinia pestis, the aetiological agent of bubonic plague, is one the deadliest pathogens known to man. Despite its historical reputation, plague is a modern disease which annually afflicts thousands of people. Public safety considerations greatly limit clinical experimentation on this organism and thus development of theoretical tools to analyze the capabilities of this pathogen is of utmost importance. Here, we report the first genome-scale metabolic model of Yersinia pestis biovar Mediaevalis based both on its recently annotated genome, and physiological and biochemical data from literature. Our model demonstrates excellent agreement with Y. pestis known metabolic needs and capabilities. Since Y. pestis is a meiotrophic organism, we have developed CryptFind, a systematic approach to identify all candidate cryptic genes responsible for known and theoretical meiotrophic phenomena. In addition to uncovering every known cryptic gene for Y. pestis, our analysis of the rhamnose fermentation pathway suggests that betB is the responsible cryptic gene. Despite all of our medical advances, we still do not have a vaccine for bubonic plague. Recent discoveries of antibiotic resistant strains of Yersinia pestis coupled with the threat of plague being used as a bioterrorism weapon compel us to develop new tools for studying the physiology of this deadly pathogen. Using our theoretical model, we can study the cell's phenotypic behavior under different circumstances and identify metabolic weaknesses which may be harnessed for the development of therapeutics. Additionally, the automatic identification of cryptic genes expands the usage of genomic data for pharmaceutical purposes.

  6. 人为因素与哈尔滨第三次鼠疫大流行%Human factors caused the third plague epidemic in Harbin

    Institute of Scientific and Technical Information of China (English)

    金东英; 李志平

    2011-01-01

    The third plague epidemic in Harbin broke out in 1946 and ended in 1954. Different from the first two plague epidemics (imported), the third prevalence was both imported and idiopathic infectious disease which was caused by human factors. Japanese troops set forbidden zones to build a biological weapon center, which destroyed the natural environment and offered a good growth condition for Citellus Undulatus. In 1945, on the eve of surrender, the Japanese blew up the Unit 731 germ factory located in a bungalow district, which caused diffusion of infected plague fleas. Mice of the district were infected and a man - made plague focus was created. During the prevalence of the third plague, prevention departments at all levels took a series of actions and with people' s efforts, the plague was effectively controlled.%哈尔滨第三次鼠疫流行始发于1946年,终止于1954年.与前两次由外来传入不同,第三次鼠疫流行是当地原发与外地传人兼有.其中,当地原发是由人为因素造成的.日军在哈尔滨市平房区建立细菌武器研制中心后,强占土地,设立禁区,致使自然环境发生变化,为黄鼠种群数量的稳定创造了条件.1945年,日军投降前夕,为掩盖其罪行,将设在哈尔滨平房区的"731部队"细菌工厂炸毁,致使大批染疫鼠蚤扩散,传染了平房及其周围地区的鼠类,最终导致人为鼠疫疫源地的形成.哈尔滨市第三次鼠疫流行期间,各级防疫部门采取了一系列措施,在广大人民群众多年的努力下,人间鼠疫和鼠间鼠疫得到有效控制,但哈尔滨市鼠疫疫源地并未根除.

  7. Better modelling practice : an ontological perpsective on multidisciplinary, model-based problem solving

    NARCIS (Netherlands)

    Scholten, H.

    2008-01-01

    Mathematical models are more and more used to support to solve multidisciplinary, real world problems of increasing complexity. They are often plagued by obstacles such as miscommunication between modellers with different disciplinary backgrounds leading to a non-transparent modelling process. Other

  8. Fowl plague virus replication in mammalian cell-avian erythrocyte heterokaryons: studies concerning the actinomycin D and ultra-violet lig sensitive phase in influenza virus replication

    International Nuclear Information System (INIS)

    The replication of fowl plague virus in BHK and L cells specifically blocked prior to infection with inhibitors of influenza virus replication (actinomycin D and ultraviolet light irradiation) has been studied by the introduction of a metabolically dormant avian erythrocyte nucleus. This permits the synthesis of just the influenza virus nucleoprotein in actinomycin D (but not ultraviolet light) blocked cells. The NP antigen is first detected in the avian erythrocyte nucleus and subsequently in the heterokaryon cytoplasm

  9. The prevention measures of plague in Hebei from 1946 to 1948%1946-1948年河北疫病防治措施

    Institute of Scientific and Technical Information of China (English)

    贾鸽

    2010-01-01

    The plague was seriously occurred in Hebei from 1946 to 1948,which had a great impact on the local social economy and people's life.The public health system was established by the government,and people were instructed about the knowledge of health consciousness and life habits for controlling effectively the plague.The measures of giving medicine freely and social assistance were taken for preventing the plague in the folk.Thus,the plague was controlled in a short time.However,the effect of prevention was limited by the objective conditions.The color of western medicine was showed from these measures,and the "modernity" of the system at that time was indicated.%1946-1948,河北发生严重疫情,对当地社会经济与民众生活产生了较大影响.政府建立公共卫生制度,并对民众进行卫生思想和生活习惯等方面知识的普及和教育,以有效防治疫病.民间则主要采用施医送药、社会救助等措施防治疫病.政府和民间社会的措施,使疫情在较短时间内得到有效遏制,但客观条件限制了防疫的成效.这一时期防治疫病的措施较多地呈现出西方防疫色彩,体现了当时卫生防疫体系的"现代性".

  10. [New nutrient medium for the cultivation and isolation of the plague microbe ChDS-37 as an element of the mobilization reserve of specialized antiepidemic teams of the Russian Inspectorate for the Protection of Consumer Rights and Human Welfare].

    Science.gov (United States)

    Mazrukho, A B; Kaminskiĭ, D I; Lomov, Yu M; Telesmanich, N P; Rozhkov, K K; Alutin, I M; Pukhov, Yu M; Prometnoĭ, V I; Fetsaĭlova, O P; Bulakhova, O G; Firsova, I A; Smolikova, L M; Bozhko, N V; Ivanova, V S; Burlakova, O S; Verkina, L M; Trukhachev, A L; Akulova, M V

    2011-04-01

    A new nutrient medium has been designed to culture and isolate the plague microbe ChDS-37 on the basis of the pancreatic digest of baker's yeast. The results of laboratory tests of the designed medium, by using 10 plague microbe strains and those of approval during the tactical and special training of a specialized antiepidemic team (SAET), suggest that the medium has some advantage over reference media and creates prerequisites for being incorporated into the mobilization reserve of a SAET.

  11. Temporal variation in the prevalence of the crayfish plague pathogen, Aphanomyces astaci, in three Czech spiny-cheek crayfish populations

    Directory of Open Access Journals (Sweden)

    Matasová K.

    2011-06-01

    Full Text Available North American crayfish species are natural hosts of the crayfish plague pathogen Aphanomyces astaci. The spiny-cheek crayfish Orconectes limosus, widespread in Central Europe, is the main reservoir of A. astaci in Czech Republic. We tested if there are temporal changes in the prevalence of infected individuals (i.e., the proportion of individuals in which the pathogen is detected in spiny-cheek crayfish populations. Crayfish from three populations shown previously to be infected to different extents (high, intermediate and low, were repeatedly sampled in different years (2004–2010 and seasons. The presence of A. astaci in the soft abdominal crayfish cuticle was tested by specific amplification of the pathogen DNA. There was no substantial temporal variation in pathogen prevalence in the highly and very lowly infected populations. However, a significant long-term as well as seasonal decrease was found in the intermediately infected population. This decline could be related to a decrease in population density over the studied years, and to crayfish seasonal moulting, respectively. A reliable estimate of pathogen prevalence in American crayfish populations thus requires repeated monitoring over years, preferably during the same season before the main period of crayfish moulting.

  12. Recognition and characterization of migratory movements of Australian plague locusts, Chortoicetes terminifera, with an insect monitoring radar

    Science.gov (United States)

    Drake, V. Alistair; Wang, Haikou

    2013-01-01

    Two special purpose insect-detecting radar units have operated in inland eastern Australia, in the region where nocturnal migratory movements of Australian plague locusts Chortoicetes terminifera occur, for over 10 years. The fully automatic radars detect individual insects as they fly directly overhead and "interrogate" them to obtain information about their characters (size, shape, and wing beating) and trajectory (speed, direction, and orientation). The character data allow locusts to be distinguished from most other migrant species. A locust index, calculated from the total count of locust-like targets for a night, provides a simple indication of migration intensity. For nights of heavy migration, the variation of numbers, directions, and speeds with both height and time can be examined. Emigration and immigration events can be distinguished, as can "transmigration," the passage overhead of populations originating elsewhere. Movement distances can be inferred, and broad source and (more tentatively) destination regions are identified. Movements were typically over distances of up to 400 km. Interpretation of radar observations requires judgment, and the present two units provide only partial coverage of the locust infestation area, but their capacity to detect major population movements promptly, and to provide information between necessarily infrequent surveys, has proved valuable.

  13. Apparent field safety of a raccoon poxvirus-vectored plague vaccine in free-ranging prairie dogs (Cynomys spp.), Colorado, USA

    Science.gov (United States)

    Tripp, Daniel W.; Rocke, Tonie E.; Streich, Sean P.; Abbott, Rachel C.; Osorio, Jorge E.; Miller, Michael W.

    2015-01-01

    Prairie dogs (Cynomys spp.) suffer high rates of mortality from plague. An oral sylvatic plague vaccine using the raccoon poxvirus vector (designated RCN-F1/V307) has been developed for prairie dogs. This vaccine is incorporated into palatable bait along with rhodamine B as a biomarker. We conducted trials in August and September 2012 to demonstrate uptake and apparent safety of the RCN-F1/V307 vaccine in two prairie dog species under field conditions. Free-ranging prairie dogs and other associated small rodents readily consumed vaccine-laden baits during field trials with no apparent adverse effects; most sampled prairie dogs (90%) and associated small rodents (78%) had consumed baits. Visual counts of prairie dogs and their burrows revealed no evidence of prairie dog decline after vaccine exposure. No vaccine-related morbidity, mortality, or gross or microscopic lesions were observed. Poxviruses were not isolated from any animal sampled prior to bait distribution or on sites that received placebo baits. We isolated RCN-F1/V307 from 17 prairie dogs and two deer mice (Peromyscus maniculatus) captured on sites where vaccine-laden baits were distributed. Based on these findings, studies examining the utility and effectiveness of oral vaccination to prevent plague-induced mortality in prairie dogs and associated species are underway.

  14. Plague history: Yersin's discovery of the causative bacterium in 1894 enabled, in the subsequent century, scientific progress in understanding the disease and the development of treatments and vaccines.

    Science.gov (United States)

    Butler, T

    2014-03-01

    The causative bacterium of plague was described and cultured by Alexandre Yersin in Hong Kong in 1894, after which transmission of bacteria from rodents by flea bites was discovered by Jean-Paul Simond in 1898. Effective treatment with antiserum was initiated in 1896, but this therapy was supplanted by sulphonamides in the 1930s and by streptomycin starting in 1947. India suffered an estimated 6 million deaths in 1900-1909, and Vietnam, during its war in 1965-1975, accounted for approximately 80% of the world's cases; since then, African countries have dominated, with >90% of the world's cases in the 1990s and early 21st century. Serological diagnosis with fraction 1 antigen to detect anti-plague antibodies was developed in the 1950s. Vaccine development started in 1897 with killed whole bacterial cells, and this was followed by a live attenuated bacterial vaccine, leading to millions of persons receiving injections, but the benefits of these vaccines remain clouded by controversy. Plasmid-mediated virulence was established in 1981, and this was followed by specific DNA methods that have allowed detection of plague genes in skeletal specimens from European graves of the sixth to 17th centuries. PMID:24438235

  15. Monitoreo of the feromonas traps in the control of the plague Lasioderma serricorne (F. in the Managerial Unit of Base Alfredo López Brito.

    Directory of Open Access Journals (Sweden)

    Marta Rosa Rodríguez Valero

    2012-12-01

    Full Text Available Due to their inigualable quality, the Cuban tobacco is one of the cultivations that bigger quantity of foreign currencies contributes to the country, but it is attacked by different plagues, in the different stages for those that it passes until its commercialization in leaves or as elaborated product. In the warehouses the most destructive plague is the Lasioderma serricorne (F. and to combat it in the Managerial Unit of Base Alfredo López Brito of Cabaiguán, the fosfamina, toxic product with high price is used in foreign currencies, the same one is applied with a bimonthly frequency, that is to say, every 60 days, for which the present work had as objective to lengthen the date of application of the fosfamina by means of the use of the feromonas traps to achieve a saving to the Unit and to improve the environmental conditions in the same one. The obtained results allowed to diminish the quantity of necessary fosfamina significantly to control the plague, the Unit saved during 4 months in those that it was carried out this work. $869.40 in national currency and $343.55 in CUC a positive impact also took place about the health of the workers and the one intones.

  16. Vaccination with F1-V fusion protein protects black-footed ferrets (Mustela nigripes) against plague upon oral challenge with Yersinia pestis

    Science.gov (United States)

    Rocke, T.E.; Smith, S.; Marinari, P.; Kreeger, J.; Enama, J.T.; Powell, B.S.

    2008-01-01

    Previous studies have established that vaccination of black-footed ferrets (Mustela nigripes) with F1-V fusion protein by subcutaneous (SC) injection protects the animals against plague upon injection of the bacterium Yersinia pestis. This study demonstrates that the F1-V antigen can also protect ferrets against plague contracted via ingestion of a Y. pestis-infected mouse, a probable route for natural infection. Eight black-footed ferret kits were vaccinated with F1-V protein by SC injection at approximately 60 days-of-age. A booster vaccination was administered 3 mo later via SC injection. Four additional ferret kits received placebos. The animals were challenged 6 wk after the boost by feeding each one a Y. pestis-infected mouse. All eight vaccinates survived challenge, while the four controls succumbed to plague within 3 days after exposure. To determine the duration of antibody postvaccination, 18 additional black-footed ferret kits were vaccinated and boosted with F1-V by SC injection at 60 and 120 days-of-age. High titers to both F1 and V (mean reciprocal titers of 18,552 and 99,862, respectively) were found in all vaccinates up to 2 yr postvaccination, whereas seven control animals remained antibody negative throughout the same time period. ?? Wildlife Disease Association 2008.

  17. “Pitiful times” – plague in Cracow in 1707–1710. A Contribution to the research into the collapse of the royal city

    Directory of Open Access Journals (Sweden)

    Emilia Karpacz

    2012-12-01

    Full Text Available The beginning of the XVIIIth century has been recorded in history of the city of Cracow as a time of war and famine. “Pitiful times” – such term was used in the chronicle of the Norbertine Sisters Convent. This cataclysms was followed by the last one and the most dangerous of them – an epidemic. The plague was a deathblow to the city on the verge of falling into ruin. One of the most important goals of the article is pointing the connections between physical, economical or spiritual state of the municipal community and enormous proportions as well as consequences of the plague. Considerations are started from describing the situation in Cracow and nearest vicinity the day before cataclysm. Subsequently Authoress characterized preventive measures, basing on municipal bills and regulations. The main part of the article presents the drama of the ordinary cracovians. To throw light on the depth of demographical, cultural and spiritual crisis in the city, the view of situation is completed by statistics based on ecclesiastical sources – records and acts of the chapters of The Dominican Order. Authoress refers also to the texts publicized in Cracow at the begging of the XVIIIth century – from medical treatises to panegyric written by Marcin Ksawery Szumliński to venerate the authorities of the city fighting against the plague.

  18. Genetic variation at the MHC DRB1 locus is similar across Gunnison's prairie dog (Cynomys gunnisoni) colonies regardless of plague history.

    Science.gov (United States)

    Cobble, Kacy R; Califf, Katy J; Stone, Nathan E; Shuey, Megan M; Birdsell, Dawn N; Colman, Rebecca E; Schupp, James M; Aziz, Maliha; Van Andel, Roger; Rocke, Tonie E; Wagner, David M; Busch, Joseph D

    2016-04-01

    Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog (Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus (DRB1) in Gunnison's prairie dog (C. gunnisoni) and quantified population genetic structure at the DRB1 versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman (SE) and Espee Ranch (ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley (AV). We found fairly low allelic diversity at the DRB1 locus, with one allele (DRB1*01) at high frequency (0.67-0.87) in all colonies. Two other DRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog (C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus (F ST = 0.033) than at microsatellite markers (F ST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced the DRB1 locus because its level of differentiation was not different from that of microsatellites in an F ST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60 C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele (DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival. PMID:27066243

  19. Genetic variation at the MHC DRB1 locus is similar across Gunnison's prairie dog (Cynomys gunnisoni) colonies regardless of plague history

    Science.gov (United States)

    Cobble, Kacy R.; Califf, Katy J.; Stone, Nathan E.; Shuey, Megan M.; Birdsell, Dawn; Colman, Rebecca E.; Schupp, James M.; Aziz, Maliha; Van Andel, Roger; Rocke, Tonie E.; Wagner, David M.; Busch, Joseph D.

    2016-01-01

    Yersinia pestis was introduced to North America around 1900 and leads to nearly 100% mortality in prairie dog (Cynomys spp.) colonies during epizootic events, which suggests this pathogen may exert a strong selective force. We characterized genetic diversity at an MHC class II locus (DRB1) in Gunnison's prairie dog (C. gunnisoni) and quantified population genetic structure at the DRB1versus 12 microsatellite loci in three large Arizona colonies. Two colonies, Seligman (SE) and Espee Ranch (ES), have experienced multiple plague-related die-offs in recent years, whereas plague has never been documented at Aubrey Valley (AV). We found fairly low allelic diversity at the DRB1 locus, with one allele (DRB1*01) at high frequency (0.67–0.87) in all colonies. Two otherDRB1 alleles appear to be trans-species polymorphisms shared with the black-tailed prairie dog (C. ludovicianus), indicating that these alleles have been maintained across evolutionary time frames. Estimates of genetic differentiation were generally lower at the MHC locus (FST = 0.033) than at microsatellite markers (FST = 0.098). The reduced differentiation at DRB1 may indicate that selection has been important for shaping variation at MHC loci, regardless of the presence or absence of plague in recent decades. However, genetic drift has probably also influenced theDRB1 locus because its level of differentiation was not different from that of microsatellites in anFST outlier analysis. We then compared specific MHC alleles to plague survivorship in 60C. gunnisoni that had been experimentally infected with Y. pestis. We found that survival was greater in individuals that carried at least one copy of the most common allele (DRB1*01) compared to those that did not (60% vs. 20%). Although the sample sizes of these two groups were unbalanced, this result suggests the possibility that this MHC class II locus, or a nearby linked gene, could play a role in plague survival.

  20. The Piano Plague: The Nineteenth-Century Medical Critique of Female Musical Education*

    Science.gov (United States)

    Kennaway, James

    2014-01-01

    The role of music in nineteenth-century female education has been seen primarily in the context of the middle class cult of domesticity, and the relationship of music to medicine in the period has generally been viewed in terms of music therapy. Nevertheless, for much of the century there was serious medical discussion about the dangers of excessive music in girls’ education. Many of the leading psychiatrists and gynaecologists of the nineteenth century argued that music could over-stimulate the nervous system, playing havoc with vulnerable female nerves and reproductive organs, and warned of the consequences of music lessons on the developing bodies of teenage girls. Two rival models of music’s effects competed and were combined. One suggested that music led to illness by provoking sensuality, imagination and sexuality; the other argued that it was a source of neurasthenic fatigue because of intellectual strain. PMID:22303771

  1. The piano plague: the nineteenth-century medical critique of female musical education.

    Science.gov (United States)

    Kennaway, James

    2011-01-01

    The role of music in nineteenth-century female education has been seen primarily in the context of the middle class cult of domesticity, and the relationship of music to medicine in the period has generally been viewed in terms of music therapy. Nevertheless, for much of the century there was serious medical discussion about the dangers of excessive music in girls' education. Many of the leading psychiatrists and gynaecologists of the nineteenth century argued that music could over-stimulate the nervous system, playing havoc with vulnerable female nerves and reproductive organs, and warned of the consequences of music lessons on the developing bodies of teenage girls. Two rival models of music's effects competed and were combined. One suggested that music led to illness by provoking sensuality, imagination and sexuality; the other argued that it was a source of neurasthenic fatigue because of intellectual strain. PMID:22303771

  2. Bacterial profiling of White Plague Disease across corals and oceans indicates a conserved and distinct disease microbiome.

    Science.gov (United States)

    Roder, Cornelia; Arif, Chatchanit; Daniels, Camille; Weil, Ernesto; Voolstra, Christian R

    2014-02-01

    Coral diseases are characterized by microbial community shifts in coral mucus and tissue, but causes and consequences of these changes are vaguely understood due to the complexity and dynamics of coral-associated bacteria. We used 16S rRNA gene microarrays to assay differences in bacterial assemblages of healthy and diseased colonies displaying White Plague Disease (WPD) signs from two closely related Caribbean coral species, Orbicella faveolata and Orbicella franksi. Analysis of differentially abundant operational taxonomic units (OTUs) revealed strong differences between healthy and diseased specimens, but not between coral species. A subsequent comparison to data from two Indo-Pacific coral species (Pavona duerdeni and Porites lutea) revealed distinct microbial community patterns associated with ocean basin, coral species and health state. Coral species were clearly separated by site, but also, the relatedness of the underlying bacterial community structures resembled the phylogenetic relationship of the coral hosts. In diseased samples, bacterial richness increased and putatively opportunistic bacteria were consistently more abundant highlighting the role of opportunistic conditions in structuring microbial community patterns during disease. Our comparative analysis shows that it is possible to derive conserved bacterial footprints of diseased coral holobionts that might help in identifying key bacterial species related to the underlying etiopathology. Furthermore, our data demonstrate that similar-appearing disease phenotypes produce microbial community patterns that are consistent over coral species and oceans, irrespective of the putative underlying pathogen. Consequently, profiling coral diseases by microbial community structure over multiple coral species might allow the development of a comparative disease framework that can inform on cause and relatedness of coral diseases. PMID:24350609

  3. Bacterial profiling of White Plague Disease across corals and oceans indicates a conserved and distinct disease microbiome

    KAUST Repository

    Roder, C.

    2014-01-29

    Coral diseases are characterized by microbial community shifts in coral mucus and tissue, but causes and consequences of these changes are vaguely understood due to the complexity and dynamics of coral-associated bacteria. We used 16S rRNA gene microarrays to assay differences in bacterial assemblages of healthy and diseased colonies displaying White Plague Disease (WPD) signs from two closely related Caribbean coral species, Orbicella faveolata and Orbicella franksi. Analysis of differentially abundant operational taxonomic units (OTUs) revealed strong differences between healthy and diseased specimens, but not between coral species. A subsequent comparison to data from two Indo-Pacific coral species (Pavona duerdeni and Porites lutea) revealed distinct microbial community patterns associated with ocean basin, coral species and health state. Coral species were clearly separated by site, but also, the relatedness of the underlying bacterial community structures resembled the phylogenetic relationship of the coral hosts. In diseased samples, bacterial richness increased and putatively opportunistic bacteria were consistently more abundant highlighting the role of opportunistic conditions in structuring microbial community patterns during disease. Our comparative analysis shows that it is possible to derive conserved bacterial footprints of diseased coral holobionts that might help in identifying key bacterial species related to the underlying etiopathology. Furthermore, our data demonstrate that similar-appearing disease phenotypes produce microbial community patterns that are consistent over coral species and oceans, irrespective of the putative underlying pathogen. Consequently, profiling coral diseases by microbial community structure over multiple coral species might allow the development of a comparative disease framework that can inform on cause and relatedness of coral diseases. 2013 The Authors Molecular Ecology John Wiley & Sons Ltd.

  4. Tendência secular da peste no Estado do Ceará, Brasil Secular plague trend in Ceará State, Brazil

    Directory of Open Access Journals (Sweden)

    Antonia Ivoneida Aragão

    2007-03-01

    Full Text Available Após a sua introdução no Ceará, Brasil, em 1900, a peste focalizou-se em sete complexos ecológicos: Chapada do Araripe e Serras da Ibiapaba, do Baturité, do Machado, das Matas, da Pedra Branca e de Uruburetama. As atividades de vigilância nesses focos no período de 1935/2004 foram desenvolvidas sucessivamente pelo Departamento Nacional de Saúde, Serviço Nacional de Peste, Departamento Nacional de Endemias Rurais, Superintendência de Campanhas de Saúde Pública, Fundação Nacional de Saúde e finalmente pela Secretaria de Vigilância em Saúde. A análise dos dados levantados sobre a ocorrência de casos humanos nesses 70 anos permite identificar diferentes padrões de circulação da enfermidade na população humana, caracterizados pela alternância de momentos de elevadas incidências e de silêncio, possibilitando estabelecer uma periodização cronológica com características epidemiológicas próprias. Conclui-se desses resultados que a peste ainda deve ser considerada uma ameaça potencial, o que justifica revitalizar as ações de vigilância epidemiológica, o que só ocorrerá com o fortalecimento de todas as instâncias do Sistema Único de Saúde.After its introduction into the State of Ceará, Brazil, in 1900, the plague was established in seven ecological complexes: Chapada do Araripe and the Ibiapaba, Baturité, Machado, Matas, Pedra Branca, and Uruburetama mountains. These natural foci were monitored successively from 1935 to 2004 by the National Health Department, National Plague Service, National Department of Rural Endemics, Superintendency of Public Health Campaigns, National Health Foundation, and finally by the National Health Surveillance Secretariat. Data analysis on human cases during these 70 years allowing identifying different plague circulation patterns in the human population, alternating high incidence with silent periods and characterizing a chronological periodicity with unique epidemiological

  5. 中国古代瘟疫史研究新进展——《宋代瘟疫的流行与防治》评介%Research Progress in Chinese Ancient Plague History - A Review ofPrevalence and Preventive Treatment of Plagues in the Song Dynasty

    Institute of Scientific and Technical Information of China (English)

    李伟霞

    2015-01-01

    Han Yi's book,Prevalence and Preventive Treatment of Plagues in the Song Dynasty, mainly focuses on the study of prevalent overview, geographical distribution, social influence, etiology and pathology of plagues in the Song Dynasty, and recognition and preventive treatment of Song government, medical scientists and ordinary people about plagues according to the theory and methods of TCM lemology and medical social history. The book had abundant historical materials, combined integrated research and case study together, firstly systemically researched and scientifically revealed the prevalence, preventive conditions and law of plagues in the Song Dynasty, solved many important medical problems and tackled technical difficulties, and had certain references for academy and reality.%韩毅著《宋代瘟疫的流行与防治》,依据中医传染病学和医学社会史的理论与方法,重点研究了宋代瘟疫的流行概况、地理分布、社会影响、病因病机,以及宋代政府、医学家和社会民众等对瘟疫的认识及采取的应对措施.该书史料丰富,采用整体研究和个案研究相结合的方法,首次系统研究、科学揭示了宋代瘟疫的流行和防治情况及其规律,解决了宋代瘟疫防治的许多重大医学问题和技术难关,具有较强的学术和现实借鉴意义.

  6. LcrV delivered via type III secretion system of live attenuated Yersinia pseudotuberculosis enhances immunogenicity against pneumonic plague.

    Science.gov (United States)

    Sun, Wei; Sanapala, Shilpa; Henderson, Jeremy C; Sam, Shandiin; Olinzock, Joseph; Trent, M Stephen; Curtiss, Roy

    2014-10-01

    Here, we constructed a Yersinia pseudotuberculosis mutant strain with arabinose-dependent regulated and delayed shutoff of crp expression (araC P(BAD) crp) and replacement of the msbB gene with the Escherichia coli msbB gene to attenuate it. Then, we inserted the asd mutation into this construction to form χ10057 [Δasd-206 ΔmsbB868::P(msbB) msbB(EC) ΔP(crp21)::TT araC P(BAD) crp] for use with a balanced-lethal Asd-positive (Asd(+)) plasmid to facilitate antigen synthesis. A hybrid protein composed of YopE (amino acids [aa]1 to 138) fused with full-length LcrV (YopE(Nt138)-LcrV) was synthesized in χ10057 harboring an Asd(+) plasmid (pYA5199, yopE(Nt138)-lcrV) and could be secreted through a type III secretion system (T3SS) in vitro and in vivo. Animal studies indicated that mice orally immunized with χ10057(pYA5199) developed titers of IgG response to whole-cell lysates of Y. pestis (YpL) and subunit LcrV similar to those seen with χ10057(pYA3332) (χ10057 plus an empty plasmid). However, only immunization of mice with χ10057(pYA5199) resulted in a significant secretory IgA response to LcrV. χ10057(pYA5199) induced a higher level of protection (80% survival) against intranasal (i.n.) challenge with ~240 median lethal doses (LD50) (2.4 × 10(4) CFU) of Y. pestis KIM6+(pCD1Ap) than χ10057(pYA3332) (40% survival). Splenocytes from mice vaccinated with χ10057(pYA5199) produced significant levels of gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), and interleukin-17 (IL-17) after restimulation with LcrV and YpL antigens. Our results suggest that it is possible to use an attenuated Y. pseudotuberculosis strain delivering the LcrV antigen via the T3SS as a potential vaccine candidate against pneumonic plague.

  7. Avian influenza (fowl plague)

    Science.gov (United States)

    Avian influenza (AI) viruses infect domestic poultry and wild birds. In domestic poultry, AI viruses are typically of low pathogenicity (LP) causing subclinical infections, respiratory disease or drops in egg production. However, a few AI viruses cause severe systemic disease with high mortality; ...

  8. A Plague of Bailouts

    Institute of Scientific and Technical Information of China (English)

    LOH; SU; HSING

    2011-01-01

    The EU starts to worry about a possible domino effect from bailouts dragging down the entire euro zone While there has l o n g b e e n anticipation of Portugal’s need for an economic bailout,the country’s formal request on April 6 still dealt a sobering blow to the current crisis in the EU.Portuguese

  9. 青海省2006~2010年鼠疫的流行病学特征分析%Epidemical analysis of plague in Qinghai from 2006-2010

    Institute of Scientific and Technical Information of China (English)

    辛有全; 王祖郧; 魏柏青; 戴瑞霞; 赵海红; 熊浩民; 张青雯; 杨晓艳; 任玲玲; 赵子婧

    2012-01-01

    目的 探讨青海省2006~2010年间青海省鼠疫流行势态,为今后鼠疫防治提供科学依据.方法 应用Excel 2003软件分析2006~2010年青海省地方病预防控制所人间鼠疫病例数据库、鼠疫监测和鼠疫疫源地调查资料.结果 5年间青海省从各种染疫动物和媒介昆虫体内分离鼠疫菌57株,主要分布在乌兰县、天峻县、格尔木等青藏铁路沿线,共检菌39株,其次为玉树县、治多县、称多县青南地区12株,环湖地区的兴海县6株.5年间累计发生人间鼠疫2起,病例13例,死亡3例,病死率为23.07%.结论 青海省鼠疫疫情仍然严峻,动物鼠疫连年不断,人间鼠疫局部地区暴发流行,应加强重点地区鼠疫监测和预警,落实各项综合防控措施,以减少鼠疫的发生和流行.%OBJECTIVE To explore the plague epidemical trend of the nearly 5 years in Qinghai province to provide basis for making the prevention and control measures. METHODS The materials of the human plague, plague monitoring and the plague foci survey in Qinghai from 2006 to 2010 were analyzed with the Excel software. RESULTS 57 strains of Yersinia peso's were isolated from the infected animals and insects in Qinghai from the recent 5 years. The Yersinia pestis was mainly distributed in Wulan, Tianjun, Ge'ermu, with a total of 39 strains, which were along the Qinghai-Xinzang railway. Another 12 strains were distributed in Yushu, Zhiduo and Chenduo. The rest 6 strains were distributed in Xinhai. Human plague was occurred every year from 2006 to 2010. In the 5 years, there were 13 plague cases and 3 of these cases died, the mortality was 23.07%. CONCLUSION The plague epidemic situation in Qinghai province is still severe, the animal plague occurs yearly, the human plague outbreaks occasionally. So as to reduce the plague occurrence, the plague monitoring and early warning in the key areas should be strengthened, and the comprehensive measures for plague prevention and control

  10. Identification of small-molecule inhibitors of Yersinia pestis Type III secretion system YscN ATPase.

    Directory of Open Access Journals (Sweden)

    Wieslaw Swietnicki

    Full Text Available Yersinia pestis is a gram negative zoonotic pathogen responsible for causing bubonic and pneumonic plague in humans. The pathogen uses a type III secretion system (T3SS to deliver virulence factors directly from bacterium into host mammalian cells. The system contains a single ATPase, YscN, necessary for delivery of virulence factors. In this work, we show that deletion of the catalytic domain of the yscN gene in Y. pestis CO92 attenuated the strain over three million-fold in the Swiss-Webster mouse model of bubonic plague. The result validates the YscN protein as a therapeutic target for plague. The catalytic domain of the YscN protein was made using recombinant methods and its ATPase activity was characterized in vitro. To identify candidate therapeutics, we tested computationally selected small molecules for inhibition of YscN ATPase activity. The best inhibitors had measured IC(50 values below 20 µM in an in vitro ATPase assay and were also found to inhibit the homologous BsaS protein from Burkholderia mallei animal-like T3SS at similar concentrations. Moreover, the compounds fully inhibited YopE secretion by attenuated Y. pestis in a bacterial cell culture and mammalian cells at µM concentrations. The data demonstrate the feasibility of targeting and inhibiting a critical protein transport ATPase of a bacterial virulence system. It is likely the same strategy could be applied to many other common human pathogens using type III secretion system, including enteropathogenic E. coli, Shigella flexneri, Salmonella typhimurium, and Burkholderia mallei/pseudomallei species.

  11. Assessment and validation of a suite of reverse transcription-quantitative PCR reference genes for analyses of density-dependent behavioural plasticity in the Australian plague locust

    Directory of Open Access Journals (Sweden)

    Blondin Laurence

    2011-02-01

    Full Text Available Abstract Background The Australian plague locust, Chortoicetes terminifera, is among the most promising species to unravel the suites of genes underling the density-dependent shift from shy and cryptic solitarious behaviour to the highly active and aggregating gregarious behaviour that is characteristic of locusts. This is because it lacks many of the major phenotypic changes in colour and morphology that accompany phase change in other locust species. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR is the most sensitive method available for determining changes in gene expression. However, to accurately monitor the expression of target genes, it is essential to select an appropriate normalization strategy to control for non-specific variation between samples. Here we identify eight potential reference genes and examine their expression stability at different rearing density treatments in neural tissue of the Australian plague locust. Results Taking advantage of the new orthologous DNA sequences available in locusts, we developed primers for genes encoding 18SrRNA, ribosomal protein L32 (RpL32, armadillo (Arm, actin 5C (Actin, succinate dehydrogenase (SDHa, glyceraldehyde-3P-dehydrogenase (GAPDH, elongation factor 1 alpha (EF1a and annexin IX (AnnIX. The relative transcription levels of these eight genes were then analyzed in three treatment groups differing in rearing density (isolated, short- and long-term crowded, each made up of five pools of four neural tissue samples from 5th instar nymphs. SDHa and GAPDH, which are both involved in metabolic pathways, were identified as the least stable in expression levels, challenging their usefulness in normalization. Based on calculations performed with the geNorm and NormFinder programs, the best combination of two genes for normalization of gene expression data following crowding in the Australian plague locust was EF1a and Arm. We applied their use to studying a target gene

  12. The application of the flow cytometry for determination of the action of serotonin on the antigenic composition and amount of DNA of plague microbe cultured at 37°C

    Science.gov (United States)

    Korsukov, Vladimir N.; Schukovskaya, Tatyana N.; Klueva, Svetlana N.; Kravtsov, Alexander L.; Polunina, Tatyana A.; Popov, Youri A.

    2003-10-01

    The results have been obtained by flow cytometry showed the significant raise of fluorescence intensity of Yersinia pestis EV cells binding FITC-labelled plague polyclonal immunoglobins after 24 h cultivation in Hottinger broth pH 7.2 at 37 °C in the presence of increasing concentration serotonin (5-Hydroxytryptamine). The presence of serotonin (5-HT) in nutrient broth at concentration of 10-5 M, 10-8 M could modulate DNA content in 37 °C growing population of plague microbe. The effect of this action depended of 5-HT concentration.

  13. Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan with an object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests

    NARCIS (Netherlands)

    Wilschut, L.I.; Addink, E.A.; Heesterbeek, J.A.P.; Davis, S.A.; Laudisoit, A.; Begon, M.; Atshabar, B.B.; Jong, S.M. de; Burdelov, L.A.; Dubyanskiy, V.M.

    2013-01-01

    Plague is a zoonotic infectious disease present in great gerbil populations in Kazakhstan. Infectious disease dynamics are influenced by the spatial distribution of the carriers (hosts) of the disease. The great gerbil, the main host in our study area, lives in burrows, which can be recognized on hi

  14. Inactivation of avirulent pgm+ and delta pgm Yersinia pestis by ultraviolet light (UV-C)

    Science.gov (United States)

    Yersinia pestis is the causative agent of bubonic plague. Though not considered a foodborne pathogen, Y. pestis can survive, and even grow, in some foods, and the foodborne route of transmission is not without precedent. As such, concerns exist over the possible intentional contamination of foods wi...

  15. Exploring Other Genomes: Bacteria.

    Science.gov (United States)

    Flannery, Maura C.

    2001-01-01

    Points out the importance of genomes other than the human genome project and provides information on the identified bacterial genomes Pseudomonas aeuroginosa, Leprosy, Cholera, Meningitis, Tuberculosis, Bubonic Plague, and plant pathogens. Considers the computer's use in genome studies. (Contains 14 references.) (YDS)

  16. Plague surveillance in Brazil: 1983 - 1992 Vigilância sorológica da peste no Brasil no período de 1983 a 1992

    Directory of Open Access Journals (Sweden)

    Alzira Maria Paiva de Almeida

    1995-12-01

    Full Text Available Plague caused by Yersinia pestis, has persisted in Brazil in several natural foci spread throughout rural areas in the States of Ceara, Paraiba, Pernambuco, Piaui, Rio Grande do Norte, Alagoas, Bahia, Minas Gerais and Rio de Janeiro. Nationwide surveillance of plague in Brazil based on serological testing started in 1983. We now present an update report of the examinations carried out in our laboratory from 1983 to 1992. The passive hemagglutination test for antibodies against fraction 1A antigen of Y. pestis and the passive hemagglutination inhibition control were employed for testing a total of 220,769 sera. Samples analyzed included 2,856 sera from clinically diagnosed plague cases or suspects, 49,848 sera from rodents of 24 species and 2 species of small wild carnivores (marsupials, 122,890 sera from dogs, and 45,175 sera from cats. Specific antibodies were found in 92 (3.22% human sera; 143 (0.29% sera from rodents of 8 species and from the two species of marsupials, 1,105 (0.90% sera from dogs and 290 (0.64% sera from cats. The presence of significant levels of specific anti-F1A antibodies among rodents and wild or domestic carnivores (dogs and cats indicates that all the Brazilian plague foci remain active in spite of the absence of human cases in some of them.A peste, infecção pela Yersinia pestis, se mantém no Brasil, em vários focos naturais, disseminados na área rural, dos Estados do Ceará, Paraiba, Pernambuco, Piaui, Rio Grande do Norte, Alagoas, Bahia, Minas Gerais e Rio de Janeiro. Desde 1983, o teste de hemaglutinação passiva para anticorpos contra a fração antigênica "F1A" de Y. pestis, vem sendo empregado ininterruptamente na vigilância da peste nos focos brasileiros. A especificidade do PHA é controlada pelo teste de inibição da aglutinação. No período de 1983 à 1992 foram examinadas 220.769 amostras de soro, sendo 2.856 de origem humana, 49.848 de roedores pertencentes à 24 espécies e de 2 espécies de

  17. 航海类学生心理问题成因及对策研究%The Causes and Countermeasures of Psychological Problems Plaguing Maritime Majors

    Institute of Scientific and Technical Information of China (English)

    郭慧萍

    2012-01-01

      Based on an analysis of psychological problems plaguing maritime majors, this article, in combination with the influence of network on their mind, makes an attempt to analyze the causes of the psychological problems and put forward countermeasures to bring students through them, which is expected to contribute to the formation of harmonious and peaceful mind.%  文章在分析了学生心理健康问题的基础上,结合网络对学生心理的影响,分析了形成心理健康问题的原因并提出了对应的解决对策,以帮助学生克服心理问题,提高其心理健康水平。

  18. The Pioneer of Cholera Vaccine and Plague Vaccine-Haffkine%霍乱疫苗鼠疫疫苗研制的先驱哈夫金

    Institute of Scientific and Technical Information of China (English)

    杨微

    2010-01-01

    沃尔德马·莫迪凯·哈夫金(1860-1930),犹太细菌学家,生于乌克兰敖德萨.1884年获得敖德萨大学科学博士学位,1889年进入巴黎巴斯德研究所工作.曾先后致力于研制霍乱疫苗与鼠疫疫苗,经自身试验后,在英属印度推行大规模的人群试验,证明相对安全有效并推广使用,挽救了众多生命.1902年,因马考魏事件,哈夫金被误判承担污染鼠疫疫苗之责,在1907年得到澄清,被誉称为"犹太人的琴纳".%Waldemar Mordecai Haffkine(1860-1930), a Jewish bacteriologist , was born in Odessa, Ukraine. He got the doctor's degree of science of Odessa University in 1884 and entered the Pasteur Institute in 1889. Then he successively committed himself to developing cholera vaccine and plague vaccine. After testing them to himself, he set up extensive field trials in British India to prove the safety and efficacy. Further inoculation saved many lives. Later he was accused for the contamination of plague vaccine in Mulkowal Disaster in 1902, and finally exonerated in 1907. Haffkine was hailed as "Jewish Jenner"

  19. Predictors for abundance of Rattus tanezumi in households of commensal rodent plague foci%云南省家鼠鼠疫疫源地室内黄胸鼠丰盛度预测因子的研究

    Institute of Scientific and Technical Information of China (English)

    尹家祥; 钟佑宏; 杜春红; 董兴齐; 杨淑惠

    2013-01-01

    Objective To explore the predictors on the abundance of Rattus (R.) tanezumi in households of commensal rodent plague foci.Methods Thirty natural villages that experienced previous plague cases in Lianghe county,Yunnan province,were selected followed by random selection of 20 households in each village through computer technique.Live traps were set in households to capture small mammals which were then identified to species in the field according to their morphological features.Data on potential factors for abundance of R.tanezumi were collected through questionnaires and field observation and were coded and computerized using EpiData software and further analyzed by hurdle regression model under R software.Results A total of 166 rodents (133 R.tanezumi and 33 Suucus murinus) were captured.Results from final multilevel hurdle regression model showed that the likelihood of R.tanezumi captures increased by 1.67-to 2.76-fold in households belonged to Dai ethnic families that stored foodstuff in metal pails,often raising dogs,and having adjacent houses.The number of R.tanezumi captures increased by 2.18-fold in the villages where over 80% of the households would raise chickens.In the villages with communal latrine,the likelihood and the number of R.tanezumi capture increased 1.93-fold and 2.38-fold,respectively.While the likelihood of R.tanezumi captures would reduce by 45%-61% in those households where there were cats and cattle being raised and maize grown in the village.The number of R.tanezumi captures would reduce by 63% in the households where there were outside toilets.Conclusion The abundance of R.tanczumi seemed to be closely related to the ecological environment factors.Programs on plague control and prevention should relate to ecological factors that influencing the abundance of R.tanezumi.%目的 研究家鼠鼠疫疫源地影响室内黄胸鼠丰盛度的因子.方法 在云南省梁河县选择30个鼠疫历史疫源村,每个村随机抽取20户

  20. Monitoring results and epidemic analysis of gerbil plague in northern Ningxia in 2009%2009年宁夏北部沙鼠鼠疫监测结果及疫情分析

    Institute of Scientific and Technical Information of China (English)

    苏鸿毅; 白学礼

    2012-01-01

    目的 分析宁夏北部沙鼠鼠疫监测结果,掌握鼠疫疫情动态,为制订防治对策提供依据.方法 收集2009年宁夏北部沙鼠鼠疫疫源地监测结果资料,统计主要宿主密度、染蚤率、蚤体指数及细菌学、血清学检查,分析该疫源地鼠疫疫情流行态势.结果 主要宿主平均密度为1.74只/hm2,平均染蚤率为28.60%,平均鼠体蚤指数为0.76.监测发现4起鼠间鼠疫疫情,共检出鼠疫菌16株,其中长爪沙鼠检菌10株、子午沙鼠2株、同型客蚤2株、秃病蚤2株.间接血凝检测(1HA)529份,发现阳性材料2份,血凝阳性率为0.38%;反向间接血凝检测(RIHA)8份,发现阳性材料7份,血凝阳性率为87.50%.结论 近年宁夏沙鼠鼠疫疫源地动物间疫情活跃,鼠密度较高,局部发生了鼠间鼠疫疫情,应加强监测力度,扩大监测范围,密切注视疫情动态,严控动物疫情的流行和蔓延,防止发生人间鼠疫.%Objective To analyze gerbil plague in northern Ningxia and the monitoring results,to master the plague epidemic dynamics,and to provide the basis for developmenting countermeasures.Methods Monitoring data of gerbil plague focus in northern Ningxia were collect in 2009,counted main host density,rate of dye fleas,flea body index and bacteriology,serology detect and analyzed the epidemic situation.Results An average density of main host was 1.74/hm2,the average rate of infected fleas was 28.60%,and the average rat body flea index was 0.76.Monitoring found 4 plagues from rat plague epidemic,plague bacteria were found in 16 strains,of which gerbils inspection bacteria 10 strains,Meriones unguiculatus 2 strains,the same type cheopis 2 strains,and bald disease fleas 2 strains.Indirect hemagglutination (IHA) was used to test 529 copies of samples,2 copies were found positive,and hemagglutination-positive rate was 0.38%; eight copies were examined by reverse indirect hemagglutination(RIHA),7 material were found positive

  1. YopP-expressing variant of Y. pestis activates a potent innate immune response affording cross-protection against yersiniosis and tularemia [corrected].

    Directory of Open Access Journals (Sweden)

    Ayelet Zauberman

    Full Text Available Plague, initiated by Yersinia pestis infection, is a rapidly progressing disease with a high mortality rate if not quickly treated. The existence of antibiotic-resistant Y. pestis strains emphasizes the need for the development of novel countermeasures against plague. We previously reported the generation of a recombinant Y. pestis strain (Kim53ΔJ+P that over-expresses Y. enterocolitica YopP. When this strain was administered subcutaneously to mice, it elicited a fast and effective protective immune response in models of bubonic, pneumonic and septicemic plague. In the present study, we further characterized the immune response induced by the Kim53ΔJ+P recombinant strain. Using a panel of mouse strains defective in specific immune functions, we observed the induction of a prompt protective innate immune response that was interferon-γ dependent. Moreover, inoculation of mice with Y. pestis Kim53ΔJ+P elicited a rapid protective response against secondary infection by other bacterial pathogens, including the enteropathogen Y. enterocolitica and the respiratory pathogen Francisella tularensis. Thus, the development of new therapies to enhance the innate immune response may provide an initial critical delay in disease progression following the exposure to highly virulent bacterial pathogens, extending the time window for successful treatment.

  2. A Novel Material Modulus Function for Modeling Viscoelastic Materials

    OpenAIRE

    Martin, Luke Andrew

    2011-01-01

    Accurately modeling damping in engineering structures has plagued scientist and engineers for decades. The integration of viscoelastic materials into engineering structures can reduce undesired vibrations and serve as an effective passive control mechanism. Various techniques have been developed to model viscoelastic materials. The growing popularity of finite element analysis in the 1980s and 1990s spawned new techniques for modeling damping in complex structures. The technique defined in th...

  3. Histopatologia da infecção por Yersinia pestis em roedores de focos de peste do Nordeste brasileiro Histopathology of Yersinia pestis infection in rodents from plague foci of Brazilian Northeast

    Directory of Open Access Journals (Sweden)

    Eridan M. Coutinho

    1982-06-01

    Full Text Available O presente trabalho mostra a histopatologia da infecção pela Yersinia pestis, entre as diferentes espécies de roedores silvestres e comensais (cricetídeos, equimídeos, murídeos e cavídeos que ocorrem na zona endêmica de peste do Nordeste do Brasil. Estes roedores foram encontrados naturalmente infectados nos campos ou inoculados experimentalmente no laboratório (vias percutânea, subcutânea ou picada de pulgas com cepas locais e/ou estrangeiras de Yersiniapestis. Quase todos os animais, exceto alguns dos cavídeos, desenvolveram a forma bubosepticêmica da peste. Entre as lesões encontradas, a necrose coagulativa multifocal do fígado, a pneumonite intersticial aguda difusa e a atrofia linfoide do baço, podem, por sua constância, ser consideradas como os principais indicadores histológicos da infecção pestosa, embora estas lesões não sejam exclusivas da peste. A diversidade e a intensidade das lesões entre os Zygodontomys lasiurus pixuna, podem explicar a mortalidade elevada desta espécie e a disseminação da peste nos focos naturais do Nordeste brasileiro. Cricetídeos e murídeos mostraram alterações histopatológicas qualitativamente semelhantes. A resistência dos cavídeos à infecção pestosa foi evidenciada pela sobrevida desses roedores à fase aguda da infecção e pelo desenvolvimento de uma reação histiocitária interna, delimitando as áreas abscedadas. è possível que estas lesões crônicas abriguem bacilos virulentos, que permitirão a reinfecção periódica das pulgas e conseqüente reativação do processo epizoótico.In this paper, the histopathological aspects of plague infection in different species of wild and domestic rodents (cricetidae, echymidae, muridae and cavidae are described. All of them had been trapped in endemic plague areas and harboured natural infection, while others were laboratory infected by different routes (percutaneous, subcutaneous rout, fleas bite. Several national and

  4. The tale of a modern animal plague: Tracing the evolutionary history and determining the time-scale for foot and mouth disease virus

    International Nuclear Information System (INIS)

    Despite significant advances made in the understanding of its epidemiology, foot and mouth disease virus (FMDV) is among the most unexpected agricultural devastating plagues. While the disease manifests itself as seven immunologically distinct strains their origin, population dynamics, migration patterns and divergence times remain unknown. Herein we have assembled a comprehensive data set of gene sequences representing the global diversity of the disease and inferred the time-scale and evolutionary history for FMDV. Serotype-specific rates of evolution and divergence times were estimated using a Bayesian coalescent framework. We report that an ancient precursor FMDV gave rise to two major diversification events spanning a relatively short interval of time. This radiation event is estimated to have taken place towards the end of the 17th and the beginning of the 18th century giving us the present circulating Euro-Asiatic and South African viral strains. Furthermore our results hint that Europe acted as a possible hub for the disease from where it successfully dispersed elsewhere via exploration and trading routes

  5. Cross-Species Antiviral Activity of Goose Interferons against Duck Plague Virus Is Related to Its Positive Self-Feedback Regulation and Subsequent Interferon Stimulated Genes Induction.

    Science.gov (United States)

    Zhou, Hao; Chen, Shun; Zhou, Qin; Wei, Yunan; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Liu, Fei; Yang, Qiao; Wu, Ying; Sun, Kunfeng; Chen, Xiaoyue; Cheng, Anchun

    2016-01-01

    Interferons are a group of antiviral cytokines acting as the first line of defense in the antiviral immunity. Here, we describe the antiviral activity of goose type I interferon (IFNα) and type II interferon (IFNγ) against duck plague virus (DPV). Recombinant goose IFNα and IFNγ proteins of approximately 20 kDa and 18 kDa, respectively, were expressed. Following DPV-enhanced green fluorescent protein (EGFP) infection of duck embryo fibroblast cells (DEFs) with IFNα and IFNγ pre-treatment, the number of viral gene copies decreased more than 100-fold, with viral titers dropping approximately 100-fold. Compared to the control, DPV-EGFP cell positivity was decreased by goose IFNα and IFNγ at 36 hpi (3.89%; 0.79%) and 48 hpi (17.05%; 5.58%). In accordance with interferon-stimulated genes being the "workhorse" of IFN activity, the expression of duck myxovirus resistance (Mx) and oligoadenylate synthetases-like (OASL) was significantly upregulated (p interferon. These findings will contribute to our understanding of the functional significance of the interferon antiviral system in aquatic birds and to the development of interferon-based prophylactic and therapeutic approaches against viral disease.

  6. Serum epidemiological investigation of F1 antibody of population having healed from plague in Yunnan Province%云南省腺鼠疫康复人群血清F1抗体流行病学调查

    Institute of Scientific and Technical Information of China (English)

    苏丽琼; 苏鹏; 宋志忠

    2008-01-01

    目的 了解云南省腺鼠疫康复人群血清F1抗体的水平分布和影响因素,为鼠疫防治提供理论依 据.方法 采用病例对照研究.以云南省1986-2005年的鼠疫监测资料为依据,设计调查表,确定调查地点和人群.采集云南省23个县的腺鼠疫康复人群血清248份作为病例组,采集7个县的有EV活菌疫苗接种史的健康人群血清295份作为人工免疫组,采集1个非疫区县的健康人群血清235份作为阴性对照组.用间接血凝试验进行检测.阳性判定标准为血清滴度≥1:20.结果 ①疫区F1抗体阳性率[22.10%(120/543)]与非疫区[0(0/235)]比较,差异有统计学意义(χ2=44.80,P0.05).④89名F1抗体阳性的腺鼠疫康复者发病时的血清滴度和康复后的滴度比较,差异无统计学意义(t=1.23,P>0.05).结论 ①云南省家鼠鼠疫疫源地人群鼠疫F1抗体阳性检出地均分布在疫区内,其地理分布与疫区分布相吻合.②自然感染鼠疫后.约有1/3的腺鼠疫康复人群能形成长期免疫,仍有2/3的人有再次感染的可能性,所形成的自然获得性免疫,其保护率和保护效果要好于接种EV活菌疫苗形成的人工获得性免疫.③人群感染鼠疫恢复后,F1抗体阳性检出率不受年龄、性别、民族、职业的影响.对于经过一定时间仍能检出F1抗体的部分腺鼠疫康复人群而言,时间的消长并不影响抗体滴度的变化,甚至能长期维持较高水平.%Objective To provide theoretical and scientific evidences for plague control,through understanding the F1 antibody level distribution and affected factor of population having healed from plague from plague natural focus of Rat.flavipectus in Yunnan Province.Methods The places and population investigated were chosen according to plague surveillant data in Yunnan Province from 1986 to 2005,using caso-control study and quesfionary. All samples were detected by indirect hemagghtination(IHA),including 248 serum samples from

  7. Plague, Politics, and Pogroms: The Black Death, Rule of Law, and the persecution of Jews in the Holy Roman Empire

    OpenAIRE

    Finley, Theresa; Koyama, Mark

    2016-01-01

    This paper explores the institutional determinants of persecution by studying the intensity of the Black Death pogroms in the Holy Roman Empire. Political fragmentation exacerbated competition for the rents generated by Jewish moneylending. This competition made Jewish communities vulnerable during periods of crisis. We test this hypothesis using data on the intensity of pogroms. In line with our model, we find that communities governed by Archbishoprics, Bishoprics, and Imperial Free Cities ...

  8. Investigation on potential plague focus in region of Kai County in three gorges reservoir area%三峡库区开县鼠疫疫源地调查

    Institute of Scientific and Technical Information of China (English)

    毛德强; 李洪; 陈小兵

    2012-01-01

    OBJECTIVE To find out if there is plague focus and the main plague hosts and vectors in the region of Kai County in three gorges reservoir area, and to identify the distributive region and the features of plague foci. METHODS Rodents were captured by cages and identified into species. Flea was counted and antibody of plague F1 was detected by IHA. RESULTS 193 rodents, including 161 rattus and 32 insectivora were caught, which were belonged to 6 species, 3 genera, and 1 families. Total density of rodents was 3.56%, the density of R. Flavipectus was 2.63%. 107 fleas were caught and the rate of rodents with fleas was 18.65% , the total flea index was 0.565. The rate of Rilavipectus with fleas was 18.88% and the flea index of R. Flavipectus was 0.566. There were 3 species of fleas belonged to 3 genera of 3 families, among them Leptopsylla segnis were 96.33%, and were the dominant fleas species, among them Xenopsylla cheopis was 2.75%. No Fl antibody of plague was detected in 193 rodents and 20 dogs. 3 000 papers to sick fleas were placed and 6 fleas were captured. CONCLUSION No plague is found in the region of Kai County in three gorges reservoir area, but there is potential risk for plague because of the widely exiting rodentia animal and flea.%目的 了解三峡库区开县是否存在鼠疫疫源地及主要宿主动物和媒介蚤类的种群构成及数量分布情况.方法 采用笼夜法捕鼠,对捕获鼠类及检获蚤类进行鉴定;计算鼠带蚤率和蚤指数;用鼠疫IHA法检测鼠疫F1抗体.结果 共捕获鼠形动物193只,总鼠密度为3.56%,黄胸鼠总密度为2.63%.啮齿目动物161只,分1科3属6种;食虫目动物32只,为1科1属1种.检获蚤107匹,鼠染蚤率为18.65%,总蚤指数为0.565,其中黄胸鼠染蚤率为18.88%,蚤指数为0.566.鼠体表蚤经鉴定分3科3属3种,缓慢细蚤(96.33%)占绝对优势,主要来自黄胸鼠,印鼠客蚤占2.75%.采集193份鼠血清和20份犬血清检测鼠疫F1抗

  9. 2007年宁夏西吉县鼠疫自然疫源地调查%Survey of natural foci of plague in Xiji county, Ningxia in 2007

    Institute of Scientific and Technical Information of China (English)

    伏卫程; 乔富贵; 朱良俊; 王兴虎; 李忠社

    2010-01-01

    Objective To learn the plague's host animals and parasitic flea composition, and to investigate the natural foci of plague in Xiji county in order to provide basic information for plague prevention and control. Methods The Citellus alaschanicus density, nocturnal rodents, the body flea, the burrow track flea, the nest flea were investigated in 8 townships (town) of Xiji county from June 11 2007 to July 25 2007. Specimens of small mammalian, fleas were collected for bacteriological and serological testing. Results The average density of the main host Citellus alaschanicus was 0.85 per hectare. The nocturnal mouse capture rate was 0.80%(24/2987).The survey found 16 species of small mammals that belonging to 3 orders, 9 families and 16 species with Citellus alaschanicus the dominant species. The Citellus alaschanicus had 2.84 fleas per body. Four families and 16 species of fleas were identified in the areas. The Citellus alaschanicus and Citellophilus Tesquorum Mongolicus were the dominant species. Plague bacteriology and serology tests were negative. Conclusions The study shows that the area is suitable for the formation of natural foci of Citellus alaschanicus plague. Surveillance is an important measure for prevention and control of the plague.%目的 了解西吉县鼠疫宿主动物及其寄生蚤的种类构成,调查西吉县鼠疫疫源情况,为预防控制鼠疫流行提供科学依据.方法 2007年6月11日至7月25日,对西吉县8个乡(镇)进行了黄鼠密度、夜行鼠、体蚤、洞干蚤、窝巢蚤调查,同时采集标本进行细菌学和血清学检验.结果主要宿主阿拉善黄鼠平均密度为0.85只/hm2,夜行鼠捕获率为0.80%(24/2987),调查发现小型兽类16种,隶属3目9科16种,以黄鼠为优势种.鼠体蚤指数为2.84,发现蚤类4科16种,以方形黄鼠蚤蒙古亚种为优势种.鼠疫细菌学、血清学检验均为阴性.结论该调查地区具备形成阿拉善黄鼠鼠疫自然疫源地的条件,开展鼠疫监

  10. Estudos bacteriológicos e sorológicos de um surto de peste no Estado da Paraíba, Brasil Bacteriological and serological studies of a plague outbreak in the Paraíba state, Brazil

    Directory of Open Access Journals (Sweden)

    Alzira Maria Paiva Almeida

    1989-06-01

    Full Text Available Foram realizados estudos bacteriológicos e/ou sorológicos para diagnóstico da infecção pestosa, em material obtido de 452 pacientes (48 positivos, 1.938 roedores e outros pequenos mamíferos (75 positivos, 4.756 cães (141 positivos e 3.047 gatos (57 positivos, oriundos de 41 municípios localizados em toda a extensão da área paraibana do Planalto da Borborema. A infecção foi encontrada em 21 municípios. Foram isoladas 20 cepas de Yersinia pestis de amostras coletadas de três pacientes e 17 roedores. Estas cepas apresentam características bioquímicas, fatores de virulência, sensibilidade aos antibióticos e poder patogênico experimental semelhantes ao de cepas isoladas anteriormente. Pelos estudos realizados não foram observados, no surto de peste que eclodiu em setembro de 1986 na Paraíba, fatores diferentes dos observados nos outros focos do nordeste do Brasil.During a plague outbreak in the Borborema Plateu focus (Paraíba, bacteriological and serological studies were carryed out in material from 452 patients (48 positives, 1,938 rodents and other small mammals (75 positives, 4,756 dogs (141 positives and 2,047 cats (57 positives obtained from 41 counties (out of which, 21 produced positive samples. Twenty Yersinia pestis strains isolated from material from 3 patients ans 17 rodents, displayed biochemical reactions, virulence factors, antibiotic susceptibility and animal experimental pathogenicity similar to those observed in strains previously isolated. According to our findings this recent plague outbreak did not exhibite different factors from those observed during prior outbreaks in other plague foci in the northeast of Brazil.

  11. 动脉粥样硬化斑块逆转的研究进展%Advanced research progress on atherosclerosis plague regression

    Institute of Scientific and Technical Information of China (English)

    王姗; 孙桂波; 罗云; 孙晓波

    2016-01-01

    Atherosclerosis is the leading cause of death all over the world.Although now many drugs have been widely used for the treatment of the disease , there are still many patients who cannot be cured , especially those with advanced atherosclerosis plague.So the research on the regression of atherosclerosis , es-pecially rapid regression is in need .The research on reverse of atherosclerosis has some breakthrough in recent twenty years , especially in the area of the rapid reversal of advanced plaques , and some new mechanisms have been confirmed , including mac-rophage migration , polarity of macrophages and the relationship between the macrophages and the change of blood lipid , which offers hope for finding more effective drugs in future .%动脉粥样硬化是常见的心血管疾病,是全世界最主要的致死原因之一。尽管现在许多治疗该疾病的药物已被广泛应用,但是仍然有许多病人不能被治愈,尤其是那些晚期的病人,所以研究动脉粥样硬化的逆转,尤其是快速逆转是非常有必要的。近二十年来关于动脉粥样硬化逆转的研究获得了一些突破性的进展,尤其是在晚期斑块的快速逆转方面,找到了一些新的机制,包括巨噬细胞的迁移、巨噬细胞的极性转化以及血脂变化与巨噬细胞之间的关系等。这些新的机制为我们找到更加有效的治疗药物带来了新的希望。

  12. Technical problems plague new planes

    Index Scriptorium Estoniae

    2010-01-01

    Läti lennuameti kontrolli käigus selgus, et airBalticu uute Bombardier Q400 NextGen lennukite uksed ei sulge piisavalt hästi, et tagada õiget õhurõhku kabiinis. Lennukite omanik on Nordic Aviation Capital

  13. 河北省康保牧场鼠疫自然疫源地植物种类调查%Retrospective investigation on plant species of plague natural focus of Kangbao pasture in Hebei province

    Institute of Scientific and Technical Information of China (English)

    刘冠纯; 李玉贵; 崔耀仁; 史献明; 乔永明; 郝存江; 任风歧; 闫东; 陈永明

    2013-01-01

    Objective To investigate plant species in the plague natural focus of Kangbao pasture in Hebei province so as to provide basis for the study on plauge on and cotrolplauge prevention and control. Methods The plant specimens were collated , photographed and recorded which were collected from 1978 to 1984 in Kangbao pasture, and established database of plant specimens. Results One hundred and ninety species, 143 genera and 52 families of the plant in Kangbao pasture before 1984 are defined. Conclusions Now we have the first understanding of the plant species in the plague natural focus of Kangbao pasture in Hebei province, which will provide foundationon for the further investigation on plant.%目的 调查河北省康保牧场的鼠疫自然疫源地植物种类,为鼠疫防治的研究提供理论依据.方法 对康保牧场1978 ~1984年采集制作的植物标本进行整理、拍照、记录,建立植物标本库.结果 1984年以前,康保牧场共有植物52科143属190种.结论 了解并掌握了该地区的植物种类及分类,为下一步对植物的调查提供研究依据.

  14. Viability of Arctan Model of f(R) Gravity for Late-time Cosmology

    CERN Document Server

    Dutta, Koushik; Patel, Avani

    2016-01-01

    $f(R)$ modifications of Einstein's gravity is an interesting possibility to explain the late time acceleration of the Universe. In this work we explore the cosmological viability of one such $f(R)$ modification proposed in (Kruglov:2013). We show that the model violates fifth-force constraints. The model is also plagued with the issue of curvature singularity in a spherically collapsing object, where the effective scalar field reaches to the point of diverging scalar curvature.

  15. Peste neumónica primaria con transmisión intrahospitalaria en La Libertad, Perú 2010 Primary pneumonic plague with nosocomial transmission in La Libertad, Peru 2010

    Directory of Open Access Journals (Sweden)

    Luis F. Donaires

    2010-09-01

    Full Text Available La peste neumónica es una forma clínica de peste, de baja frecuencia y alta letalidad, transmitida por la inhalación directa de Yersinia pestis proveniente de un animal o de persona a persona. Objetivo. Describir las características clínicas y epidemiológicas de los casos de un brote de peste neumónica primaria humana en el norte de Perú. Materiales y métodos. Se revisaron las historias clínicas de los casos confirmados de peste neumónica primaria presentados en un brote ocurrido en la región de La Libertad, en el mes de julio de 2010, asimismo, se efectuó la búsqueda e investigación de contactos. Resultados. Se identificó el caso índice y tres casos adicionales, de estos últimos, dos fueron infecciones intrahospitalarias relacionadas con el caso índice. La presentación clínica inicial se caracterizó por fiebre de inicio súbito, escalofríos, mialgias y dolor torácico y evolución en menos de 24 horas a hipotensión arterial y cianosis. El inicio del tratamiento específico varió de 2 a 12 días, observándose que los casos con inicio precoz de tratamiento tuvieron un mejor resultado clínico. La letalidad fue de 50% (2/4. Conclusión. Se evidenció la transmisión intrahospitalaria de peste neumónica en el Perú con manifestaciones graves y alta letalidad.Pneumonic plague is one of the clinical forms of plague, of low frequency and high mortality, transmitted by direct inhalation of Yersinia pestis coming from an animal or from person to person. Objective. To describe the clinical and epidemiological characteristics of the cases of primary pneumonic plague in an outbreak in the north of Peru. Materials and methods. The clinical records of the confirmed cases of primary pneumonic plague presenting in an outbreak occurring in La Libertad, in July 2010, were reviewed, also the search and contact investigation was performed. Results. The index case was identified, as well as three additional cases, out of these, two were

  16. 阿拉善黄鼠鼠疫疫源地蚤类组成及区系分布%The flea species composition and fauna distribution in Spermophilus alaschanicus plague foci

    Institute of Scientific and Technical Information of China (English)

    郭鹏; 安君胜; 王晓宏

    2011-01-01

    Objective To analyze and sort the fleas in the plague foci of Spermophilus alaschanicus in the Ganning loess plateau for providing the epidemiological data on fleas for the control and prevention of plague. Methods The methods of descriptive epidemiology was used for the integrated analysis of the composition of fleas based on the data sorted according to the Siphonaptera, Class lasecta, the Chinese Fauna. Results A total of 62 species of fleas (subspecies) , which belonged to 26 genera and 7 families, were found in the plague foci of S. alaschanicus. There were 6 species (subspecies) of fleas that were widely distributed in the foci of all the administrative divisions (countries) of the region; There were some specific flea species in some each administrative divisions, there being 4 species specific to Haiyuan county, 1 species to Xiji, 15 to Huining county and 3 to Pingchuan district. Conclusion Citellophilus tesquorum mongolicus was the most common and stable species with a high detection rate, being dorminant in the bodies of mice, burrows and nests. So it is the major vector of the host S. alaschanicus in the foci with other rodents and birds also serving as its hosts. In particular, the exchange of fleas parasitic on birds is of great importance in the transmission of plague, which is worth exploring in terms of the epidemiology of animal plague.%目的 通过对甘宁黄土高原阿拉善黄鼠鼠疫疫源地所获蚤类进行整理,为鼠疫防治提供蚤类流行病学信息.方法 应用流行病学描述研究方法,按对该疫源地内蚤类组成系统整理并进行综合分析.结果 在阿拉善黄鼠鼠疫疫源地内共发现蚤类62种(亚种),隶属7科26属;根据行政区划在各县(区)疫源地内广泛分布的蚤有6种(亚种),各行政区间特有蚤种为海原县4种,西吉县1种,平川区3种,会宁县15种.结论 方形黄鼠蚤蒙古亚种最常见,数量稳定,检菌率高,无论在鼠体、洞口洞干、窝巢中均占优

  17. Analysis of potential risk factor of plague in Wanzhou section of the There Gorges Reservoir area%2001-2009年三峡水库万州段鼠疫潜在危险因素分析

    Institute of Scientific and Technical Information of China (English)

    罗超; 万时学; 毛德强; 冉贞卫; 丁建武; 李丹; 刘纯华

    2010-01-01

    Objective To find out the potential risk factor of plague in Wanzhou section of the Three Gorges Reservoir area, and to provide scientific basis for prevention and control of plague. Methods Rodents were captured by rat traps/cages at night and identified into species in Wanzhou section of the Three Gorges Reservoir area from 2001 to 2009. Flea was counted and serum antibodies against plague F1 of rats, cats and dogs were detected by indirect hemagglutination (IHA). Plague surveillances were performed in human beings and rats. Results The rodents captured belonged to 9 species, 2 families, 2 orders and 1 classes. The average indoor rodent density was 1.16% (961/82 558), and was 1.12% (1345/119 671) outdoors. Rattus norvegicus was the dominant species,accounting for 50.37%. The proportion of R. Flavipectus was 3.80% in 2004, 4.50% in 2008 and 10.12% in 2009,showing an increasing trend year by year. There were three kinds of mice infected fleas in Wanzhou, which including Xenopsylla cheopis, Leptopsylla segnis and Ctenocephalides felis. The average rate of flea infected mice was 1.18%(82/6959) and the total flea index was 0.036. No F1 antibody against plague was detected in 6959 dogs and 160 cats serum samples. Conclusions No plague is found in Wanzhou section of the Three Gorges Reservoir area. But R.Flavipectus, Xenopsylla cheopis and Leptopsylla segnis are dominant species in Wanzhou section, and the proportion of which shows an increasing trends year by year. There is a potential risk of plague outbreaks in Wanzhou section of the Three Gorges Reservoir area.%目的 分析三峡水库万州段鼠疫潜在危险因素,为全区鼠疫防治及预警工作提供科学依据.方法 2001-2009年,在三峡水库万州段的9个镇(乡),采用夹夜法和笼夜法捕鼠,对捕获鼠类及检获蚤类进行鉴定,计算鼠带蚤率和蚤指数;用鼠疫间接血凝试验(IHA)法检测鼠、猫、犬血清鼠疫F1抗体,开展人间及鼠间鼠疫疫情监测.

  18. 河北省鼠疫自然疫源地鸟类窝巢蚤调查%Investigation on fleas in bird nest in natural foci of plague of Hebei Province

    Institute of Scientific and Technical Information of China (English)

    任风歧; 崔耀仁; 刘冠纯; 史献明

    2013-01-01

    Objectives To study fleas in the nets of dominant birds and its effect on the spread of the plague in natural foci of Hebei province and provide basis for the plague prevention and control.Methods Fleas were collected and classified from birds' nests and Yersinia pestisof fleas was tested.Results Totally 59 fleas were collected from 11 out of 96 nests.Infection rate of fleas was 11.46%,Flea index was 0.61.two species,1 genera and 1 family of fleas were classified and they were Ceratophyllus gallinae tribulis and Ceratophyllus garei which belong to Ceratophyllidae and Ceratophyllus.Conclusions The dominant species of birds were sparrow,magpie,sand Braun,chickadee,crow in natural foci of plague of Hebei province.Although Yersinia pestiswas not found,theory of Yersinia pestisspread by birds would be further studied.%目的 研究河北省鼠疫自然疫源地优势种鸟类窝巢蚤种类及其在鼠疫流行中的作用,为河北省的鼠疫防治工作提供参考.方法 获取自然状态下鸟的窝巢蚤,对获得的蚤进行分类鉴定和鼠疫细菌学检验.结果 共调查鸟类窝巢96个,染蚤窝巢11个,获蚤59只,染蚤率为11.46%,蚤指数为0.61;隶属于1科1属2种,为角叶蚤科的角叶蚤属的禽角叶蚤欧亚亚种和粗毛角叶蚤.结论 河北省鼠疫自然疫源地内鸟类优势种有麻雀、喜鹊、山雀、乌鸦,蚤的种类较少,虽然没有获得鼠疫耶尔森氏菌的证据,但是对于鼠疫耶尔森氏菌由鸟类传入的自然保菌学说有待进一步研究.

  19. Space Flight Cable Model Development

    Science.gov (United States)

    Spak, Kaitlin

    2013-01-01

    This work concentrates the modeling efforts presented in last year's VSGC conference paper, "Model Development for Cable-Harnessed Beams." The focus is narrowed to modeling of space-flight cables only, as a reliable damped cable model is not yet readily available and is necessary to continue modeling cable-harnessed space structures. New experimental data is presented, eliminating the low-frequency noise that plagued the first year's efforts. The distributed transfer function method is applied to a single section of space flight cable for Euler-Bernoulli and shear beams. The work presented here will be developed into a damped cable model that can be incorporated into an interconnected beam-cable system. The overall goal of this work is to accurately predict natural frequencies and modal damping ratios for cabled space structures.

  20. Stationary configurations of the Standard Model Higgs potential: electroweak stability and rising inflection point

    CERN Document Server

    Iacobellis, Giuseppe

    2016-01-01

    We study the gauge-independent observables associated with two interesting stationary configurations of the Standard Model Higgs potential (extrapolated to high energy according to the present state of the art, namely the NNLO): i) the value of the top mass ensuring stability of the SM electroweak minimum, and ii) the value of the Higgs potential at a rising inflection point. We examine in detail and reappraise the experimental and theoretical uncertainties which plague their determination, finding that: i) stability of the SM is compatible with the present data at the 1.5 sigma level; ii) despite the large theoretical error plaguing the value of the Higgs potential at a rising inflection point, application of such configuration to models of primordial inflation displays a 3 sigma tension with the recent bounds on the tensor-to-scalar ratio of cosmological perturbations.

  1. Dissemination of a highly virulent pathogen: tracking the early events that define infection.

    OpenAIRE

    Rodrigo J. Gonzalez; M Chelsea Lane; Wagner, Nikki J.; Weening, Eric H.; Miller, Virginia L.

    2015-01-01

    The series of events that occurs immediately after pathogen entrance into the body is largely speculative. Key aspects of these events are pathogen dissemination and pathogen interactions with the immune response as the invader moves into deeper tissues. We sought to define major events that occur early during infection of a highly virulent pathogen. To this end, we tracked early dissemination of Yersinia pestis, a highly pathogenic bacterium that causes bubonic plague in mammals. Specificall...

  2. Dissemination of a Highly Virulent Pathogen: Tracking The Early Events That Define Infection

    OpenAIRE

    Rodrigo J. Gonzalez; Lane, M. Chelsea; Wagner, Nikki J.; Weening, Eric H.; Miller, Virginia L.

    2015-01-01

    The series of events that occurs immediately after pathogen entrance into the body is largely speculative. Key aspects of these events are pathogen dissemination and pathogen interactions with the immune response as the invader moves into deeper tissues. We sought to define major events that occur early during infection of a highly virulent pathogen. To this end, we tracked early dissemination of Yersinia pestis, a highly pathogenic bacterium that causes bubonic plague in mammals. Specificall...

  3. 瘟疫、谣言与社会恐慌--以湖南为例的研究%PLAGUE,RUM ORS AND SOCIAL PANIC Taking Hunan as a Case

    Institute of Scientific and Technical Information of China (English)

    杨鹏程; 王洪铭

    2014-01-01

    Before 1949, the plague of Hunan province was frequent, which seriously harm ed people's lives and health. The enorm ous social panic often originated from a large num ber of infected people or death tolls, even the"whole fam ilies was on the verge of extinction"in a short tim e. When the plague struck, all people get into the m ood of terrified worry. At this very m om ent, on the one hand the governm ent should tim ely take various effective m easures given proper m edical assistance, active control and prevention;on the other hand it m ust strengthen the propaganda and popularization of knowledge of epidem ic disease prevention and control, nip it in the bud, guide public opinion correctly and try to relieve the doubts from the public's m inds and restore calm . Otherwise, if let the rum or relay an erroneous m essage blindly and m agnify infinitely, it would bring catastrophic consequences.%建国前湖南瘟疫频仍,严重危害民众的生命健康。大量人口的染疫与死亡,甚至短时期内“整家整户皆绝”,往往造成巨大的社会恐慌。在瘟疫发生、人心惶惑之际,政府一方面要及时采取各种有效措施施医送药、积极防治;另一方面必须加强疫病防治知识的宣传普及,防微杜渐,正确引导社会舆论,尽释群疑,安定人心。否则任由谣言以讹传讹,无限放大,将会带来灾难性的后果。

  4. Comparison of biological characteristics of Yersinia pestis strains in two rodent plague cases isolated from Shanxi province%陕西省两起鼠间鼠疫流行鼠疫菌生物学特性比较

    Institute of Scientific and Technical Information of China (English)

    安翠红; 李伟华; 陈宝宝; 孙养信

    2013-01-01

    Objective To know etiological characteristics of plague in animals of Shanxi province by comparing the biological characteristics of Yersinia pestis strains in two rodent plague cases. Methods To compare and analyze biological characteristics, virulence, virulent factors and plasmids isolated from Yersinia pestis strains from 2000 to 2001 and in 2006. Results All identified strains had the same biological characteristics with fermenting arabinose, decomposing glycerides, not fermenting rham-nose, Maltose and not removing nitrogen. All tested strains had Fland Pstl. Only one strain lost Pgm factor and other eighteen had four virulent factors in the strains isolated from 2000 to 2001 , however, five tested strains had lost VW factor and two lost Pgm factor in 2006. The results showed that strains LD50 were 41 to l80 in 2000 to 2001 and strains LD50 werelO to 1. 25 billion in 2006. Plasmids testing were not carried out in 2000 to 2001 ; three plasmids of 6, 45 and 65MD were tested out in 2006. Conclusion All biological characteristics of strains were identified to be in coincidence with Ordos Plateau gerbil jird ecotype. However, the virulence and virulent factors which caused the two plague cases were different. Yersinia pestis strains isolated from 2000 to 2001 were much stronger than that of 2006 and three of five strains tested had high virulence and two had low virulence.%目的 通过对两起鼠间鼠疫流行鼠疫菌生物学特性进行比较,了解陕西省动物间鼠疫流行的病原特点.方法 对2000~2001年、2006年动物鼠疫流行期间所分离菌株的生化、毒力、毒力因子及质粒进行比较分析.结果 被鉴定菌株发酵阿胶糖,分解甘油,不发酵鼠李糖、麦芽糖,脱氮阴性.所有测试菌株含有F1和Pstl因子,2000~2001年19株鼠疫菌除1株Pgm±外,均含有4种毒力因子,2006年5株测试鼠疫菌均不含VW因子,2株不含Pgm因子.2000~2001年5株测试菌LD50在41 ~ 180个菌之间,2006年5

  5. Analysis of Elimination Effect of Enzyme-Combined Mouthwash on Dental Plague%复合酶漱口液消减牙菌斑的效果分析

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    龋齿的发生与牙齿表面附着的牙菌斑和细菌的作用密切相关,文中旨在通过复合酶液降解葡聚糖和淀粉类物质来消除牙菌斑的存在基础,考察去除牙菌斑的效果.实验通过测定20名志愿者使用含不同浓度的复合酶漱口液、不含酶漱口液(无酶对照组)及市售精油类漱口液前后的Tureskey改良的Q-H菌斑指数的改变情况,考察β-葡聚糖酶和α-淀粉酶复合酶漱口液降解牙菌斑的效果.统计学结果显示含酶量大于0.5 mg/L时,牙菌斑降低率显著优于无酶对照组;且含酶量大于5.0 mg/L时,牙菌斑降低率优于某市售精油类漱口液.结果表明含酶漱口液对抑制牙菌斑的作用效果明显.文中研究为龋齿的日常防治提供了理论依据.%Dental caries is closely related to dental plaque , a biofilm in which bacteria attach to the teeth surface . This paper deals with the feasibility of eliminating dental plague by using a kind of mouthwash in which combined enzymes are used to degrade glucan and starch .In the investigation , the Tureskey modified Q-H indexes of 20 vo-lunteers were measured to compare the elimination effect of the enzyme-combined mouthwash , the mouthwash with-out enzymes and the commercially available mouthwash with essential oil .Statistical results indicate that , when the enzyme content is higher than 0.5 mg/L, the mouthwash containing β-glucanase and α-amylase is more effec-tive than the one without enzymes; and that, when the enzyme content is higher than 5.0 mg/L, the enzyme-com-bined mouthwash presents a dental plague elimination rate higher than that of the commercially available mouth -wash .It is thus concluded that the mouthwash with combined enzymes is effective in eliminating dental plague . This research lays a theoretical foundation for developing products for the daily prevention of dental caries .

  6. A comparative study of DNA barcode of plague host animals between different foci%不同疫源地鼠疫宿主动物的DNA条形码比较研究

    Institute of Scientific and Technical Information of China (English)

    刘芳; 常子丽; 胡艳红; 武正华; 李建云; 马志东; 张忠兵

    2016-01-01

    目的 评估应用DNA条形码技术鉴定不同地理区域物种的可行性.方法 选取内蒙古自治区3个鼠疫自然疫源地4种鼠疫宿主动物的DNA条形码进行比较,分析GC碱基含量和密码子偏好性、计算遗传距离,采用邻接法(NJ)构建分析系统发育树.结果 不同疫源地的五趾跳鼠GC碱基含量比较差异有统计学意义(F=5.34,P<0.05),长爪沙鼠疫源地五趾跳鼠的GC碱基含量变异较大,与其他疫源地五趾跳鼠比较差异均有统计学意义(P均< 0.05).不同疫源地间同一鼠种很少存在种内密码子变异位点;各鼠种种内平均遗传距离均<1%,种间遗传距离均>18%.结论 各鼠种DNA条形码具有特异性,不存在物种间共享,不因地理位置变化而改变.利用DNA条形码可以达到鼠疫宿主动物分子鉴定的目的.%Objective To illustrate more accurately the feasibility of DNA barcode technology in species identification in different geographical areas.Methods Four plague host animals were selected from three plague natural foci in Inner Mongolia for DNA barcode comparison,GC base content,codon preference and genetic distance calculation,and a phylogenetic tree was constructed.Results Compared between different foci of A llactaga sibirica,the difference of base content was statistically significant (F =5.34,P < 0.05);the variation of Meriones unguiculatus focus Allactaga sibirica base content was larger,and compared with other foci Allactaga sibirica,the difference was statistically significant (all P < 0.05).Different foci between one species rarely exist in codon sites.The genetic distance of intraspecific was less than 1%,and the genetic distance of interspecific was more than 18%.Conclusions DNA barcode of each species is specific,with no interspecific species sharing,and does not change with geographical position.Molecular identification of plague host animal is effective by DNA barcode.

  7. Analysis of the monitor results of Marmota sibirica plague foci from 2004 to 2008%2004-2008年蒙古旱獭鼠疫疫源地监测结果分析

    Institute of Scientific and Technical Information of China (English)

    范蒙光; 赵天飙

    2011-01-01

    Objective To master of the characteristics of development and variation in plague natural foci of Marmota sibirica, and to analyze the plague monitoring results from 2004 to 2008. Methods From May to September every year, we monitored plague in Manzhouli, Chenbaerhuqi, Xinbaerhuzuoqi, Xinbaerhuyouqi,Ewenkeqi and Yakeshi city. The monitored area was 20 000 - 40 000 hm2 in every county. The density of Marmota,ground squirrel and moonlighting rats was surveyed by path method, one-day bow-clip method and a clamp was placed every five meters, respectively. The classification and identification of ectoparasite fleas were done by using low power lens. The fleas in the ground squirrel hole were collected by flannel rubber stick, then classified and identified. According to "National Standard of Plague Diagnostic Criteria"(GB 15991-1995), the collected rats and fleas were detected by isolation and cultured Yersinia pestis, the serums of collected rats were tested by indirect hemagglutination test. Results In five years, the density of Marmota and ground squirrel was 0.010/hm2 and 0.602/hm2, respectively. The capture rate of moonlighting rats was 2.69% (258/9600). The flea infection rate of Marmota was 17.54%(10/57) and the fleas index was 2.54. The fleas infection rate of ground squirrel was 28.40%(213/750) and the fleas index was 1.01. Flea infection rat of ground squirrel hole was 5.60%(46/822) and the fleas index was 0.17. The total number of various hosts of Yersinia pestis detected was 1351, the groups number of the variety of cultured fleas was 127, and the pathogen test results were negative. The number of serum tested was 1064, positive number was 43, and the detection rate was 4.04%(43/1064). The highest positive titer was 1 : 1280. Other than 2006, the remaining four years were found positive for blood clotting material; positive serum was found in a total of three regions, they were Manzhouli, Xinbaerhuzuoqi, and Xinbaerhuyouqi; and 30, 12 and 1 copies

  8. 小鹅瘟—鹅副黏病毒病二联油乳剂灭活疫苗的研究%Study on an Oil-Emulsion Inactivated Vaccine against Gosling Plague and Goose Paramyxovirus Disease

    Institute of Scientific and Technical Information of China (English)

    李琳; 姚新华; 邵洪泽; 尹荣兰; 任科研; 许志林

    2012-01-01

    In order to prevent the gosling plague and the goose paramyxovirus disease, the JLDA strain of the gosling plague and the strain JLSY of the goose paramyxovirus were selected to produce the oil-emulsion inactivated vaccine against gosling plaque, goose paramyxovirus disease. Applied the PALL condensing technic to condense the virus, the vaccine was ensured that the antigen content was enough and the proportion was equilibrium. The 10# white oil was selected as the adjuvant and the proportion of the oil and water was 1 : 1, the ropy degree of the vaccine was low. The results showed that the immune effect was not lower than that of the corresponding vaccine, and indicated that the goose parvovirus and the goose paramyxovirus could not be interfered. The results were that the protection rate of the vaccine preserved for 15 months was lower than that of the vaccine preserved for 12 months and showed that the two combined vaccine could be preserved for at least 12 months at 2 to 8℃.%为了有效防制小鹅瘟和鹅副黏病毒病对雏鹅的危害,分别选用免疫原性良好的小鹅瘟JLDA株和鹅副黏病毒JLSY株制作抗原液,应用PALL浓缩技术进行浓缩,保证灭活病毒抗原含量足,比例均衡.选取10号白油佐剂,按油相与水相比1∶1配制成复相制备二联灭活苗,黏稠度低.结果显示,对鹅的免疫效力不低于相应单苗,两种病毒之间没有交互抑制作用,且二联灭活苗安全性能好,疫苗吸收良好.种、雏鹅产生抗体快,免疫种、雏鹅,具有产生免疫力早,保护期长等特点,于2~8℃至少保存12个月.

  9. Protection Afforded by Fluoroquinolones in Animal Models of Respiratory Infections with Bacillus anthracis, Yersinia pestis, and Francisella tularensis.

    Science.gov (United States)

    Peterson, Johnny W; Moen, Scott T; Healy, Daniel; Pawlik, Jennifer E; Taormina, Joanna; Hardcastle, Jason; Thomas, John M; Lawrence, William S; Ponce, Cindy; Chatuev, Bagram M; Gnade, Bryan T; Foltz, Sheri M; Agar, Stacy L; Sha, Jian; Klimpel, Gary R; Kirtley, Michelle L; Eaves-Pyles, Tonyia; Chopra, Ashok K

    2010-01-01

    Successful treatment of inhalation anthrax, pneumonic plague and tularemia can be achieved with fluoroquinolone antibiotics, such as ciprofloxacin and levofloxacin, and initiation of treatment is most effective when administered as soon as possible following exposure. Bacillus anthracis Ames, Yersinia pestis CO92, and Francisella tularensis SCHU S4 have equivalent susceptibility in vitro to ciprofloxacin and levofloxacin (minimal inhibitory concentration is 0.03 μg/ml); however, limited information is available regarding in vivo susceptibility of these infectious agents to the fluoroquinolone antibiotics in small animal models. Mice, guinea pig, and rabbit models have been developed to evaluate the protective efficacy of antibiotic therapy against these life-threatening infections. Our results indicated that doses of ciprofloxacin and levofloxacin required to protect mice against inhalation anthrax were approximately 18-fold higher than the doses of levofloxacin required to protect against pneumonic plague and tularemia. Further, the critical period following aerosol exposure of mice to either B. anthracis spores or Y. pestis was 24 h, while mice challenged with F. tularensis could be effectively protected when treatment was delayed for as long as 72 h postchallenge. In addition, it was apparent that prolonged antibiotic treatment was important in the effective treatment of inhalation anthrax in mice, but short-term treatment of mice with pneumonic plague or tularemia infections were usually successful. These results provide effective antibiotic dosages in mice, guinea pigs, and rabbits and lay the foundation for the development and evaluation of combinational treatment modalities. PMID:21127743

  10. Modeling, Control and Coordination of Helicopter Systems

    CERN Document Server

    Ren, Beibei; Chen, Chang; Fua, Cheng-Heng; Lee, Tong Heng

    2012-01-01

    Modeling, Control and Coordination of Helicopter Systems provides a comprehensive treatment of helicopter systems, ranging from related nonlinear flight dynamic modeling and stability analysis to advanced control design for single helicopter systems, and also covers issues related to the coordination and formation control of multiple helicopter systems to achieve high performance tasks. Ensuring stability in helicopter flight is a challenging problem for nonlinear control design and development. This book is a valuable reference on modeling, control and coordination of helicopter systems,providing readers with practical solutions for the problems that still plague helicopter system design and implementation. Readers will gain a complete picture of helicopters at the systems level, as well as a better understanding of the technical intricacies involved. This book also: Presents a complete picture of modeling, control and coordination for helicopter systems Provides a modeling platform for a general class of ro...

  11. Resistance to Innate Immunity Contributes to Colonization of the Insect Gut by Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Shaun C Earl

    Full Text Available Yersinia pestis, the causative agent of bubonic and pneumonic plague, is typically a zoonotic vector-borne disease of wild rodents. Bacterial biofilm formation in the proventriculus of the flea contributes to chronic infection of fleas and facilitates efficient disease transmission. However prior to biofilm formation, ingested bacteria must survive within the flea midgut, and yet little is known about vector-pathogen interactions that are required for flea gut colonization. Here we establish a Drosophila melanogaster model system to gain insight into Y. pestis colonization of the insect vector. We show that Y. pestis establishes a stable infection in the anterior midgut of fly larvae, and we used this model system to study the roles of genes involved in biofilm production and/or resistance to gut immunity stressors. We find that PhoP and GmhA both contribute to colonization and resistance to antimicrobial peptides in flies, and furthermore, the data suggest biofilm formation may afford protection against antimicrobial peptides. Production of reactive oxygen species in the fly gut, as in fleas, also serves to limit bacterial infection, and OxyR mediates Y. pestis survival in both insect models. Overall, our data establish the fruit fly as an informative model to elucidate the relationship between Y. pestis and its flea vector.

  12. 论小说《鼠疫》中的英雄观及其现实意义%On the Heroism of the Novel The Plague and Its Practical Significance

    Institute of Scientific and Technical Information of China (English)

    胡园园

    2015-01-01

    As the first to focus on the absurdity,in the novel The Plague which relates to death and salva⁃tion,Camus showed us the collective rebellion in absurd situation and suggested a best heroism beyond absurdi⁃ty. Born in absurdity,this concept of hero takes the form of action and is well interpreted in the contemporary world. It is different from the unreachable idol and shows the most pristine appearance:“face reality,love life, act positively”with the truth of“two plus two equals four”. This heroism,with its infectivity and quality of clos⁃ing to ordinary life,will be widely adopted by today’s society and carried forward in the new period as life attitude.%作为集中讨论荒诞的第一人,加缪在涉及死亡与拯救主题的小说《鼠疫》中,为人们展示了荒诞境遇下的集体反抗行为,并暗示了一种超越荒诞的最佳英雄主义。这种英雄观诞生于荒诞,表现为行动,诠释在当代。它区别于遥不可及的时代偶像,以“二加二等于四”的真理呈现出最质朴的英雄面貌:“面对现实,热爱生活,积极行动”。

  13. Geographical distribution of host animals of plague in residential areas in Yunnan Province%2007-2012年云南省居民区鼠疫宿主动物调查及其地理分布

    Institute of Scientific and Technical Information of China (English)

    刘霖; 刘正祥; 杜春红; 洪梅; 吴爱国; 宋志忠; 高子厚

    2014-01-01

    Objective To investigate the geographical distribution of plague host animals in residential areas and the association between plague and its distribution pattern in Yunnan Province.Methods A systematic investigation on fauna and community ecology of rodents was carried out in residential areas of 17 counties(cities) of Yunnan Province,southwestern China with different longitude,latitude and elevation from May 2007 to November 2012.The characteristics of the spatial distribution of flea communities along environmental gradients were analyzed using community structure indexes.Results A total of 390 small mammals were trapped in seventeen counties (cities),and the mammals were classified into 11 species and 7 genus in 4 families.Among all small host mammals,Rattus tanezumi,Rattus nitidus and Rattus norvegicus were dominant species of host animals in residential areas,accounting for 33.85% (132/390),20.77% (81/390) and 16.92% (66/390),respectively.The horizontal distribution of rodents showed that Rattus tanezumi was the widest species in residential areas,which was found at the longitude 98°-105°,followed by Rattus norvegicus,Rattus yunnanensis and Mus musculus.The vertical and latitudinal distributions of rodents were similar in residential areas.Rattus tanezumi was also the widest distributed species,which was observed at the latitude 21°-< 28°N and at the altitude 500-< 3 500 m; the constituent of Rattus tanezumi showed similar trends of leaning peak curves,first gradually increasing and then decreasing with the increase of latitude and elevation; Rattus tanezumi gradually changed into Rattus nitidus and Apodemus chevrieri,et al.The richness spatial distribution patterns of host animals showed similar trends of leaning peak curves which gradually increased and then decreased with increasing of longitude and latitude; the highest richness was observed at the longitude 98°-< 101°E and at the latitude 23°-< 28°N.While,the richness spatial d

  14. Analysis and Surveillance on Major Host Animal Species and Vectors of Plague in Shenzhen City%深圳市鼠疫宿主动物及媒介监测分析

    Institute of Scientific and Technical Information of China (English)

    王敬忠; 李怀昕; 谢旭; 梅树江; 林一曼; 李迎慧; 马汉武; 程锦泉

    2011-01-01

    目的 通过对深圳市鼠疫宿主动物及媒介的监测和分析,为鼠疫防治工作提供依据.方法 采用笼日法;采集全部活鼠体表蚤鉴定后分类;采用鼠疫间接血球凝集试验(IHA)查鼠血清F1抗体,脏器压印法分离鼠疫耶尔森氏菌.结果 2005年共捕获鼠形动物472只,捕获率8.25%,隶属于2目2科3属4种,褐家鼠占87.50%;2010年共捕获鼠形动物320只,捕获率7.52%,隶属于2目2科4属5种,褐家鼠占94.06%;两次监测均显示褐家鼠为本市优势鼠种.南山区鼠密度下降趋势明显,二者差异有统计学意义(x2= 48.7,P<0.001).2005年发现129只鼠形动物寄生565匹印鼠客蚤,染蚤率为27.33%,总蚤指数为1.20;2010年发现35只鼠形动物寄生79匹印鼠客蚤,染蚤率为10.93%,总蚤指数为0.25.染蚤率(x2=31.2,P<0.001)和总蚤指数(x2=1 130.0,P<0.001)呈下降趋势.2005年获鼠血清458份,2010年获鼠血清315份,鼠疫F1抗体检测均为阴性.2005年鼠脏器压印培养407份,2010年鼠脏器压印培养320份,均未分离出鼠疫杆菌.结论 深圳市未发现鼠间鼠疫疫情,鼠疫媒介生物密度呈下降趋势,南山区鼠密度下降趋势明显.%Objective To investigate and analyze the species of the hosts and the vectors of plague in Shenzhen, and to provide the scientific evidence for prevention and treatment of plague. Methods Host animals were captured by daily cage- caught. Fleas were classified after being identified. Yersinia pestis F1 antibodies were detected by IHA and Yersinia pestis was separated by organ impression. Results A total of 472 rat- like animals were captured in 2005, belonging to 2 orders, 3 genera, and 4 species. The capture rate was 8.25%. R. Norvegicus constituted 87.50% of the total number. A total of 320 rat- like animals were captured in 2010, belonging to 2 orders, 4 genera, and 5 species. The capture rate was 7.52%. R. Norvegicus, constituted 94.06% of the total number. R. Norvegicus was

  15. The Physical Internet and Business Model Innovation

    Directory of Open Access Journals (Sweden)

    Diane Poulin

    2012-06-01

    Full Text Available Building on the analogy of data packets within the Digital Internet, the Physical Internet is a concept that dramatically transforms how physical objects are designed, manufactured, and distributed. This approach is open, efficient, and sustainable beyond traditional proprietary logistical solutions, which are often plagued by inefficiencies. The Physical Internet redefines supply chain configurations, business models, and value-creation patterns. Firms are bound to be less dependent on operational scale and scope trade-offs because they will be in a position to offer novel hybrid products and services that would otherwise destroy value. Finally, logistical chains become flexible and reconfigurable in real time, thus becoming better in tune with firm strategic choices. This article focuses on the potential impact of the Physical Internet on business model innovation, both from the perspectives of Physical-Internet enabled and enabling business models.

  16. High-Speed Shaft Bearing Loads Testing and Modeling in the NREL Gearbox Reliability Collaborative: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    McNiff, B.; Guo, Y.; Keller, J.; Sethuraman, L.

    2014-12-01

    Bearing failures in the high speed output stage of the gearbox are plaguing the wind turbine industry. Accordingly, the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) has performed an experimental and theoretical investigation of loads within these bearings. The purpose of this paper is to describe the instrumentation, calibrations, data post-processing and initial results from this testing and modeling effort. Measured HSS torque, bending, and bearing loads are related to model predictions. Of additional interest is examining if the shaft measurements can be simply related to bearing load measurements, eliminating the need for invasive modifications of the bearing races for such instrumentation.

  17. Seasonal prevalence of white plague like disease on the endemic Brazilian reef coral Mussismilia braziliensis Prevalencia estacional de la enfermedad de la plaga blanca en el coral endémico de Brasil Mussismilia braziliensis

    Directory of Open Access Journals (Sweden)

    Ronaldo Francini-Filho

    2010-01-01

    Full Text Available The reef coral Mussismilia braziliensis Verril, 1968 is endemic to the eastern Brazilian coast, representing a major reef-building species in the region. This coral is threatened by extinction due to the recent proliferation of a white-plague like (WPL disease. Despite its severe impacts, the environmental factors leading to outbreaks of WPL disease are still poorly understood. This study describes the seasonal prevalence of WPL disease on M. braziliensis in the Abrolhos Bank, on the southern coast of Bahia Brazil. In situ estimates showed that WPL disease was about 4.5 times more prevalent in summer (January 2007, mean sea surface temperature 27.4°C than in winter (July 2007, 25.0°C. This result suggests that the prevalence of WPL disease in M. braziliensis is temperature-dependent, supporting the hypothesis that warmer oceans are facilitating the proliferation of coral diseases worldwide.El coral Mussismilia braziliensis Verril, 1968 es endémico de la costa este de Brasil y representa una de las principales especies constructoras de arrecifes coralinos en dicha region. Este coral se encuentra bajo la amenaza de extincion debido la reciente propagacion de la enfermedad llamada la plaga blanca (PB. Pese los fuertes impactos, los factores ambientales responsables por epidemias de la PB aún son poco conocidos. En este estudio se describe la prevalencia estacional de la PB en M. braziliensis en el Banco de Abrolhos, ubicado en la costa sur de Bahia, Brasil. Estimaciones in situ comprueban que la prevalencia de esta molestia ha sido cerca de 4,5 veces mayor en verano (enero de 2007, temperatura media del agua superficial del mar 27,4°C, que en invierno (julio de 2007; 25,0°C. Este resultado sugiere que la prevalencia de la enfermedad PB en M. braziliensis es dependiente de la temperatura, reforzando la hipótesis de que los océanos mas cálidos estén facilitando la propagacion de enfermedades coralígenas en todo el mundo.

  18. Clostridium difficile – an emerging plague

    OpenAIRE

    D. Spînu; Ovidiu Bratu; Popescu, R.; Marcu, D; A. Rădulescu; Dan Mischianu

    2015-01-01

    Introduction: Clostridium difficile infection stands nowadays as one of the major emerging health problems still underestimated. Only in 2009 the European Society of Clinical Microbiology and Infection (ESCMID) was able to publish guidelines for this serious disease. Actually the guidelines were updated in 2013 so we can speak of a united action towards the resolution of this healthcare problem. Methods: This is a review article aiming to shed light in various aspects of clostridium dif...

  19. Frequently Asked Questions (FAQ) about Plague

    Science.gov (United States)

    ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Updates Subscribe Listen Page last updated April ... Del.icio.us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Download page Subscribe to RSS Get email ...

  20. Transparency issues still plague business in Latvia

    Index Scriptorium Estoniae

    2010-01-01

    Läti Kaubanduskoja teatel ei ole investorid rahul korruptsiooni ja läbipaistvusega Läti ärikeskkonnas. Läti valitsuselt oodatakse tõhusamaid samme majandus- ja investeerimistingimuste parandamiseks

  1. Identification of rodent residues by DNA barcoding technology in plague areas%DNA条形码技术在鼠疫疫区啮齿动物残体鉴定中的应用

    Institute of Scientific and Technical Information of China (English)

    安翠红; 陈宝宝; 孙养信; 范锁平; 霍丽霞

    2014-01-01

    目的 应用DNA条形码技术对陕西省鼠疫疫区啮齿动物残体进行宿主分类鉴定,分析DNA条形码技术鉴定方法的可行性.方法 收集外形经形态学鉴定的7个鼠种8个不同部位62份残体样本,提取组织中DNA,经PCR、电泳、测序及结果比对等步骤,分析线粒体细胞色素C氧化酶Ⅰ亚基(COI)基因序列.将COI基因序列利用美国国家生物技术信息中心(NCBI)运行BLAST程序进行序列同源性比较;利用邻接(NJ)法构建COI基因序列的NJ系统树.结果 除3份毛发外,足部、尾巴、皮毛、肌肉、肋骨、耳朵、眼球均扩增出COI基因,扩增产物片段的大小与预期片段的大小相近(700 bp),且条带单一.DNA测序获得了59份残体标本的COI基因,其中长爪沙鼠、黑线仓鼠、子午沙鼠、三趾跳鼠、小毛足鼠、褐家鼠、五趾跳鼠序列同源性比较显示,COI基因与对应宿主所对应的基因均具有高度的同源性(99.0%,98.1%,99.8%,98.9%,99.5%,99.1%,98.3%).NJ法显示,59份残体标本的COI基因构建出7个序列的NJ系统树,同鼠种不同标本聚为一类.结论 DNA条形码技术能够对鼠疫疫区啮齿动物残体进行物种分类鉴定,鉴定结果可靠.%Objective To identify rodent residues using DNA barcoding technology in plague areas of Shaanxi and to analyze the feasibility of DNA barcoding method.Methods DNA extraction,PCR,electrophoresis and sequence determination and alignment were used to determine the cytochrome C oxidase Ⅰ (COI) gene sequence from 62 residues of 7 species identified by morphology in 8 different parts.COI gene sequence was analyzed using BLAST software of American National Center for Biotechnology Information (NCBI) for sequence homology comparison and the phylogenetic tree was constructed by using the neighbor joining(NJ)method of COI gene sequence.Results In addition to the hair,CO I genes of the feet,the tail,the fur,the muscle,the ribs,the ear,and the eye were

  2. 北京市土地覆盖遥感和鼠疫鼠情调查%Remote sensing of land coverage and investigation of plague risk among small mammals in Beijing, China

    Institute of Scientific and Technical Information of China (English)

    窦相峰; 孙玉兰; 黎新宇; 王全意; 阿孜古丽·加帕; 李阳桦; 关增智; 王小梅; 吕燕宁; 田丽丽; 李旭; 张秀春

    2013-01-01

    Objective To map the land coverage by remote sensing, and to investigate the relationship between land coverage and the species diversity and density of small mammals in Beijing. Methods The 2009 land coverage for Beijing was provided by the M0DIS Land Cover Type product (MCD12Q1) from NASA. Small beasts were captured using the trap-at-night method during 2009-2011 for species identification and density calculation. Results According to plant functional type (PFT) scheme, the proportion of urban and construction land was 12.19%, and the proportion of cropland was 39.24%. Natural vegetation accounted for 48.27%, of which 31.28% was covered by broadleaf forests, 10.91% by shrubs, and 3.68% by coniferous forests. The area of grass was relatively small, making up only 2.40% of the total area. Eight hundred and eighty one small mammals belonging to 10 species were captured with trap-at-night method. Of which 871 (98.86%) belonged to nine species of rodents and 10 belonged to one species of insectivores. The species compositions were statistically different in three different habitats including broadleaf forest, shrub, and cropland. The dominant rodents in broadleaf forest and cropland were Niviventer confucianus and Apodemus peninsulae, whereas N. Confucianus and Rattus norvegicus were dominant in shrub. Conclusion The major hosts of plague confirmed in China could not adapt to the vegetation landscape with high proportion of trees and shrubs and low proportion of grasses in Beijing. Although the dominant rodents could be infected by Yersinia pestis, there is a small chance of natural foci of plague emerging in Beijing.%目的 了解北京市土地覆盖分类及分布,并分析土地覆盖类型与北京市鼠种和鼠密度的关系.方法 使用美国国家航空航天局(NASA)2009年中分辨率成像光谱仪(MODIS)陆地标准产品(MCD12Q1)提取北京市土地覆盖类型和比例,并在2009-2011年用夹夜法捕捉小型兽类鉴

  3. Models

    DEFF Research Database (Denmark)

    Juel-Christiansen, Carsten

    2005-01-01

    Artiklen fremhæver den visuelle rotation - billeder, tegninger, modeller, værker - som det privilligerede medium i kommunikationen af ideer imellem skabende arkitekter......Artiklen fremhæver den visuelle rotation - billeder, tegninger, modeller, værker - som det privilligerede medium i kommunikationen af ideer imellem skabende arkitekter...

  4. A study to investigate the prevalence of animal plague in Horqin Right Wing Front County, Inner Mongolia,2012%2012年内蒙古科尔沁右翼前旗动物鼠疫监测结果分析

    Institute of Scientific and Technical Information of China (English)

    辛双全; 郭长山; 海岩; 白乌云; 王振强

    2013-01-01

    Objectives To investigate the prevalence of animal plague in Horqin Right Front County and provide scientific bases for prevention and treatment of the disease.Methods Plague surveillance was carried out according to the requirements of National Plague Monitoring Programme at 3 monitoring points in Horqin Right Front County in 2012.Squirrel density,the number of small rats,rat fleas,pathogenic and serological surveillance of Yersinia pestis were included in the study.Results A total of 356 dauricus were captured,the average density was 0.88 rats/hm2; female and male ratio was 1 ∶ 1.31 and the female embryo rate was 96.46%.The captured 13 small nocturnal mice belonged to 2 species,which included 10 cricetulus barabensis and 3 cricetulus longicaudatus,and the capture rate of small nocturnal mouse was 4.33% (13/300).A total of 98 rat fleas were collected from 25 rats; rat flea carrying rate was 100%(25/25) and flea index was 3.92.Eighty rat burrows were detected,and flea index was 0.188.Pathogen test results were negative.Indirect hemagglutination test was used to examine 356 rat sera and 1 serum was positive.Conclusions Detection of positive rat sera has proved the existence of plague epidemic in Horqin Right Front County.Therefore,the work on plague prevention and control has a long way to go.%目的 掌握内蒙古科尔沁右翼前旗动物间鼠疫疫情,为预防控制鼠疫发生与流行提供科学依据.方法 2012年,按照《全国鼠疫监测方案》要求,在科尔沁右翼前旗3个鼠疫监测点开展鼠疫监测,包括黄鼠密度监测、野外小型鼠数量监测、鼠体寄生蚤检查、鼠疫菌病原学及血清学监测.结果 共捕获黄鼠356只,平均密度为0.88只/hm2,雌雄比例为1∶1.31,剖检雌性鼠胚胎率为96.46%.共捕获野外小型鼠2种,13只,捕获率为4.33%(13/300).其中,黑线仓鼠10只,仓鼠3只.捕获的25只活鼠均带蚤,染蚤率为100% (25/25).共检出98匹蚤,蚤指数为3.92.

  5. O controle de pragas urbanas na qualidade do alimento sob a visão da legislação federal Urban plague control in food quality according to brazilian federal legislation

    Directory of Open Access Journals (Sweden)

    Ricardo Soares Matias

    2007-08-01

    Ordinance Law 209 that establishes the Brazilian Code of Foods. The Brazilian Governmental Decree 1428 of 26 November, 1993 from the Brazilian Ministry of Health (MS innovates the relationship of the contributory factors for food contamination presenting in the guidelines the establishment of good manufacturing practices and services rendered in the area of foods, the de-infestation that includes the sanitization plan used by an establishment. A new vision of the decisive factors of food contamination has been created, which is the control of mice and insects. This procedure integrates all the legal documents that were produced by the MS and Brazilian Ministry for Agriculture, Livestock and Supply (MAPA concerning the control of food. Even the publication of the Brazilian Governmental Decree 275/2002-MS, the control of urban plagues could be done by trained teams of establishments that carried out: production / industrialization, division, storage and transporting of industrialized food, handling, preparation, storage, distribution, transport, sale display and the delivery of food prepared for consumption, such as restaurants, buffets, sweet shops, industrial kitchens, institutional kitchens, delicatessens, snack bars, bakeries, pastry shops, restaurants, among others. Regarding its publication, the chemical control is only carried out by the PCO in accordance with the Brazilian Governmental Decree 18/2000-MS. However, this does not mean the legal responsibility of food companies has been taken away that should include in the SOP (Standardized Operational Procedure the control of pests, whether it be physical and/or chemical.

  6. 云南省野鼠疫源地鼠疫指示动物血清F1抗体流行病学调查%Seroepidemiological survey of F1 antibody of indicator animals in wild rodents loci of plague in YunnanProvince

    Institute of Scientific and Technical Information of China (English)

    梁云; 陈志军; 宋志忠; 郭英; 杨智明; 吴爱国; 张福新; 张正飞; 和映天; 和伟

    2008-01-01

    Objective To study on the effect of indicator animals in plague surveillance throngh detecting F1 antibody against Yersiniapestis(Y.pestis)in indicator animals in wild rat plague foci,provide scientific evidence for plague control and determining the range of epidemic area.Methods According to investigation scheme of wild rodents plagne foci in Yunnan Province,indicator animals Canis familiarils and Felis catu(C.familiarils and F.catus)related to the plague were investigated in 75 villages,14 township and 10 counties around Yulong County,and living rodents were captured by cage,sera of indicator animals and rodents relevant to plague were simultaneously collected and detected for F1 antibody against Y.pestis using indirect hemagglutination(IHA).Results Seropositivity rate of indicator animals were 6.76%(202/2987),being 24.69% in C.familiaris and 24.69% in F.catus,there were statistical significance(X2=87.32,P<0.01)between C familiaris and F catus,the latter beingmore than the former.But F1 antibody of rodents sera were not detected,its seropositivity rate was zero.there was a statistical significance(P<0.01)between indicator animals and rodents.Conclusions Through serocpidemiological survey of indicator animals,new wild rat plague natural focus has been confirmed in YuLong County and Gucheng District in LiJiang City,therefore,serocpidemiological surveillance of indicator animals is very important for plague control and prevention.%目的 通过对云南省野鼠疫源地指示动物血清鼠疫F1抗体阳性率的调查,探讨鼠疫指示动物在鼠疫监测中的作用,为鼠疫防治和确定疫区范围提供科学依据.方法 按,在玉龙县及其周围地区共10个县所属14个乡(镇)的75个自然村,对鼠疫指示动物(犬和猫)进行调查,同时采用5 m布笼野外捕捉活鼠.取指示动物和活鼠血清,间接血凝试验OHA)法检测动物血清中的鼠疫F1抗体.结果 共采集鼠疫指示动物血清2897份,F1抗体阳性血清202

  7. The healing philosopher: John Locke's medical ethics.

    Science.gov (United States)

    Short, Bradford William

    2004-01-01

    This article examines a heretofore unexplored facet of John Locke's philosophy. Locke was a medical doctor and he also wrote about medical issues that are controversial today. Despite this, Locke's medical ethics has yet to be studied. An analysis of Locke's education and his teachers and colleagues in the medical profession, of the 17th century Hippocratic Oath, and of the reaction to the last recorded outbreak of the bubonic plague in London, shines some light on the subject of Locke's medical ethics. The study of Locke's medical ethics confirms that he was a deontologist who opposed all suicide and abortion through much of pregnancy.

  8. Structural Characterisation of the Beta-Ketoacyl-Acyl Carrier Protein Synthases, FabF and FabH, of Yersinia pestis

    OpenAIRE

    Jeffrey D. Nanson; Himiari, Zainab; Swarbrick, Crystall M. D.; Forwood, Jade K.

    2015-01-01

    Yersinia pestis, the causative agent of bubonic, pneumonic, and septicaemic plague, remains a major public health threat, with outbreaks of disease occurring in China, Madagascar, and Peru in the last five years. The existence of multidrug resistant Y. pestis and the potential of this bacterium as a bioterrorism agent illustrates the need for new antimicrobials. The β-ketoacyl-acyl carrier protein synthases, FabB, FabF, and FabH, catalyse the elongation of fatty acids as part of the type II f...

  9. Fighting disease and epidemics: Ricardo Jorge and the internationalization of Portuguese science.

    Science.gov (United States)

    de Almeida, Maria Antónia Pires

    2013-06-01

    Ricardo Jorge was one of the principal doctors responsible for the sanitary transition in Portugal. He created and enforced the most important policies for disease control, both endemic and epidemic, which scourged the western world between the mid nineteenth century and beginning of the twentieth. His professional training and academic and scientific performances reveal Ricardo Jorge's value in Portuguese science and his efforts for its internationalization. His capacities were confirmed by the emergency of the sanitary situations with which he was confronted and by the authorities' confidence in him, by putting him in charge of the bubonic plague elimination process.

  10. Aïllament, identificació i caracterització de nematodes entomopatògens en sòls de cultius del Baix Llobregat i les muntanyes de Prades i possible utilització per al control de plagues

    OpenAIRE

    Suárez Cano, Pedro

    2015-01-01

    Durant els últims anys s'estan realitzant nombrosos estudis sobre l'ús de nematodes com a mètode de control biològic. Mitjançant el present treball s'ha pretès realitzar un aïllament de nematodes entomopatògens en les zones de Prades i del Baix Llobregat i un cop aïllats i identificats realitzar diferents proves d'eficàcia d'aquests aïllats com mètodes de control de diferents plagues. Per dur a terme aquests assajos s'han realitzat diferents sistemes pel manteniment i producció de les pob...

  11. A Statistical Model Of A Heavy Quark Meson

    CERN Document Server

    Smith, A L

    1999-01-01

    An effective field approximation, similar to the Thomas- Fermi model of an atom, is proposed for studying the thermodynamic properties of a heavy quark meson within a quark-gluon plasma. The approximation for the case of an SU(2) gauge theory with central monopole and dipole point charges is shown to be plagued with singularities. For the case of SU(3) with a central core, to which the quark is confined, an approximation is developed for a high density low temperature system. Thermodynamic quantities are calculated as functions of of environmental parameters and the heavy quark meson is shown to be unstable. Instability is shown to increase with increased density. QCD corrections to the model are expected to render the configuration stable for sufficiently low density and temperature.

  12. Instability in interacting dark sector: An appropriate Holographic Ricci dark energy model

    CERN Document Server

    Herrera, Ramon; Videla, Nelson

    2016-01-01

    In this paper we investigate the consequences of phantom crossing considering the perturbative dynamics in models with interaction in their dark sector. By mean of a general study of gauge-invariant variables in comoving gauge, we relate the sources of instabilities in the structure formation process with the phantom crossing. In order to illustrate these relations and its consequences in more detail, we consider a specific case of an holographic dark energy interacting with dark matter. We find that in spite of the model is in excellent agreement with observational data at background level, however it is plagued of instabilities in its perturbative dynamics. We reconstruct the model in order to avoid these undesirable instabilities, and we show that this implies a modification of the concordance model at background. Also we find drastic changes on the parameters space in our model when instabilities are avoided.

  13. Practical Use of Computationally Frugal Model Analysis Methods.

    Science.gov (United States)

    Hill, Mary C; Kavetski, Dmitri; Clark, Martyn; Ye, Ming; Arabi, Mazdak; Lu, Dan; Foglia, Laura; Mehl, Steffen

    2016-03-01

    Three challenges compromise the utility of mathematical models of groundwater and other environmental systems: (1) a dizzying array of model analysis methods and metrics make it difficult to compare evaluations of model adequacy, sensitivity, and uncertainty; (2) the high computational demands of many popular model analysis methods (requiring 1000's, 10,000 s, or more model runs) make them difficult to apply to complex models; and (3) many models are plagued by unrealistic nonlinearities arising from the numerical model formulation and implementation. This study proposes a strategy to address these challenges through a careful combination of model analysis and implementation methods. In this strategy, computationally frugal model analysis methods (often requiring a few dozen parallelizable model runs) play a major role, and computationally demanding methods are used for problems where (relatively) inexpensive diagnostics suggest the frugal methods are unreliable. We also argue in favor of detecting and, where possible, eliminating unrealistic model nonlinearities-this increases the realism of the model itself and facilitates the application of frugal methods. Literature examples are used to demonstrate the use of frugal methods and associated diagnostics. We suggest that the strategy proposed in this paper would allow the environmental sciences community to achieve greater transparency and falsifiability of environmental models, and obtain greater scientific insight from ongoing and future modeling efforts. PMID:25810333

  14. Investigating the ?Trojan Horse? Mechanism of Yersinia pestis Virulence

    Energy Technology Data Exchange (ETDEWEB)

    McCutchen-Maloney, S L; Fitch, J P

    2005-02-08

    Yersinia pestis, the etiological agent of plague, is a Gram-negative, highly communicable, enteric bacterium that has been responsible for three historic plague pandemics. Currently, several thousand cases of plague are reported worldwide annually, and Y. pestis remains a considerable threat from a biodefense perspective. Y. pestis infection can manifest in three forms: bubonic, septicemic, and pneumonic plague. Of these three forms, pneumonic plague has the highest fatality rate ({approx}100% if left untreated), the shortest intervention time ({approx}24 hours), and is highly contagious. Currently, there are no rapid, widely available vaccines for plague and though plague may be treated with antibiotics, the emergence of both naturally occurring and potentially engineered antibiotic resistant strains makes the search for more effective therapies and vaccines for plague of pressing concern. The virulence mechanism of this deadly bacterium involves induction of a Type III secretion system, a syringe-like apparatus that facilitates the injection of virulence factors, termed Yersinia outer membrane proteins (Yops), into the host cell. These virulence factors inhibit phagocytosis and cytokine secretion, and trigger apoptosis of the host cell. Y. pestis virulence factors and the Type III secretion system are induced thermally, when the bacterium enters the mammalian host from the flea vector, and through host cell contact (or conditions of low Ca{sup 2+} in vitro). Apart from the temperature increase from 26 C to 37 C and host cell contact (or low Ca{sup 2+} conditions), other molecular mechanisms that influence virulence induction in Y. pestis are largely uncharacterized. This project focused on characterizing two novel mechanisms that regulate virulence factor induction in Y. pestis, immunoglobulin G (IgG) binding and quorum sensing, using a real-time reporter system to monitor induction of virulence. Incorporating a better understanding of the mechanisms of virulence

  15. Analysis of monitoring results on plague's host animal and its medium insects in Quanzhou city of Fujian province between 2000 and 2009%2000-2009年福建省泉州市鼠疫宿主动物及媒介昆虫监测分析

    Institute of Scientific and Technical Information of China (English)

    李锋平; 王伟明; 杨德林; 张庆虎

    2011-01-01

    Objective To examine the composition and distribution of animal reservoir of plague in Quanzhou city, Fujian province, and so as to accumulate basic data for making the plague prevention and control measures. Methods Rodents were captured by cages in six monitoring spots of Quanzhou city between 2000 and 2009. Then rodents and flea species were identified. Rats liver and spleen homogenates were detected of plague F1 antigen by reverse indirect hemagglutination test (RIHA); rats serum were detected of plague F1 antibody by indirect hemagglutination test (IHA). Results A total of 26 264 rodents were captured between 2000 and 2009.Rattus norvegicus and Rattus flavipectus were dominant species, which were accounted for 45.97% (12 074/26 264)and 32.01%(8407/26 264), respectively. The account of Rattus flavipectus captured between 2005 and 2009 was (26.99 ± 2.46)% and (37.03 ± 3.79)% between 2000 and 2004. The difference was statistically significant (t =4.97, P < 0.05). Total rodent densities was (6.86 ± 1.44)%, including(5.36 ± 1.83)% in mountains and (6.81 ±1.66)% in coastal areas, respectively, and the difference was not statistically significant(t =1.01, P > 0.05). Total flea index and flea infection rate of rodents were 1.39 ± 0.34 and (35.90 ± 5.34)%, respectively. Xenopsylla Cheopis index was 1.20 and free flea index was 0.009. Flea infection rate was (32.36 ± 0.96)% between 2005 and 2009, which was lower than (39.44 ± 0.39)% between 2000 and 2004(t =2.76, P < 0.05). Conclusions The major rodent species found in Quanzhou city is Rattus norvegicus. Xenopsylla Cheopis is the dominant flea species.Spreading of plague among Rattus is not found.%目的 了解福建省泉州市鼠疫宿主动物及媒介的种群构成及数量分布情况,为鼠疫防治工作积累基础资料。方法 2000 - 2009年在泉州市6个监测点采用笼日法捕鼠,并对捕获鼠类及检获蚤类进行鉴定;取鼠肝和脾匀浆,采用反

  16. Dissemination of a highly virulent pathogen: tracking the early events that define infection.

    Directory of Open Access Journals (Sweden)

    Rodrigo J Gonzalez

    2015-01-01

    Full Text Available The series of events that occurs immediately after pathogen entrance into the body is largely speculative. Key aspects of these events are pathogen dissemination and pathogen interactions with the immune response as the invader moves into deeper tissues. We sought to define major events that occur early during infection of a highly virulent pathogen. To this end, we tracked early dissemination of Yersinia pestis, a highly pathogenic bacterium that causes bubonic plague in mammals. Specifically, we addressed two fundamental questions: (1 do the bacteria encounter barriers in disseminating to draining lymph nodes (LN, and (2 what mechanism does this nonmotile bacterium use to reach the LN compartment, as the prevailing model predicts trafficking in association with host cells. Infection was followed through microscopy imaging in addition to assessing bacterial population dynamics during dissemination from the skin. We found and characterized an unexpected bottleneck that severely restricts bacterial dissemination to LNs. The bacteria that do not pass through this bottleneck are confined to the skin, where large numbers of neutrophils arrive and efficiently control bacterial proliferation. Notably, bottleneck formation is route dependent, as it is abrogated after subcutaneous inoculation. Using a combination of approaches, including microscopy imaging, we tested the prevailing model of bacterial dissemination from the skin into LNs and found no evidence of involvement of migrating phagocytes in dissemination. Thus, early stages of infection are defined by a bottleneck that restricts bacterial dissemination and by neutrophil-dependent control of bacterial proliferation in the skin. Furthermore, and as opposed to current models, our data indicate an intracellular stage is not required by Y. pestis to disseminate from the skin to draining LNs. Because our findings address events that occur during early encounters of pathogen with the immune response

  17. 关于731部队鼠疫报告书的初步解读——基于美国解密日本细菌战档案的调查%Preliminary Interpretation on the Report of Plague by Unit 731 : Based on the Investigation of U.S. Declassified Files of Japanese Biological Warfare

    Institute of Scientific and Technical Information of China (English)

    杨彦君

    2013-01-01

    “The Report of Q” is saved in the U.S.Library of Congress,which is the report on autopsy of people plague infected in the Changchun and Nongan areas by Unit 731 in 1943.The main contents,research types and research methods of “the Report of Q” are analyzed on the basis of the anatomical data recorded in “the Report of Q”,and the information about the infection path and degree of the organs such as heart,lung and tonsil,which further reveals the historical facts of Unit 731 actually doing the research on bacterial infection in the name of the “Epidemic Prevention”.%“Q报告”保存在美国国会图书馆,是731部队于1943年对长春和农安地区鼠疫感染者进行解剖的报告书.依据“Q报告”所记录的解剖数据,心脏、肺、扁桃体等器官感染路径和感染程度等信息,梳理分析了“Q报告”的主要内容、研究类型和研究方法,进一步揭露了731部队以“防疫”为名实际进行细菌感染研究的历史事实.

  18. No compelling cosmological models come out of magnetic universes which are based in nonlinear electrodynamics

    CERN Document Server

    Garcia-Salcedo, Ricardo; Quiros, Israel

    2013-01-01

    Here we investigate the cosmic dynamics of Friedmann-Robertson-Walker universes -- flat spatial sections -- which are driven by nonlinear electrodynamics (NLED) Lagrangians. We pay special attention to the check of the sign of the square sound speed since, whenever the latter quantity is negative, the corresponding cosmological model is classically unstable against small perturbations of the background energy density. Besides, based on causality arguments, one has to require that the mentioned small perturbations of the background should propagate at most at the local speed of light. We also look for the occurrence of curvature singularities. Our results indicate that several cosmological models which are based in known NLED Lagrangians, either are plagued by curvature singularities of the sudden and/or big rip type, or are violently unstable against small perturbations of the cosmological background -- due to negative sign of the square sound speed -- or both. In addition, causality issues associated with su...

  19. ARIMA Model Estimated by Particle Swarm Optimization Algorithm for Consumer Price Index Forecasting

    Science.gov (United States)

    Wang, Hongjie; Zhao, Weigang

    This paper presents an ARIMA model which uses particle swarm optimization algorithm (PSO) for model estimation. Because the traditional estimation method is complex and may obtain very bad results, PSO which can be implemented with ease and has a powerful optimizing performance is employed to optimize the coefficients of ARIMA. In recent years, inflation and deflation plague the world moreover the consumer price index (CPI) which is a measure of the average price of consumer goods and services purchased by households is usually observed as an important indicator of the level of inflation, so the forecast of CPI has been focused on by both scientific community and relevant authorities. Furthermore, taking the forecast of CPI as a case, we illustrate the improvement of accuracy and efficiency of the new method and the result shows it is predominant in forecasting.

  20. Dynamics of genome rearrangement in bacterial populations.

    Directory of Open Access Journals (Sweden)

    Aaron E Darling

    Full Text Available Genome structure variation has profound impacts on phenotype in organisms ranging from microbes to humans, yet little is known about how natural selection acts on genome arrangement. Pathogenic bacteria such as Yersinia pestis, which causes bubonic and pneumonic plague, often exhibit a high degree of genomic rearrangement. The recent availability of several Yersinia genomes offers an unprecedented opportunity to study the evolution of genome structure and arrangement. We introduce a set of statistical methods to study patterns of rearrangement in circular chromosomes and apply them to the Yersinia. We constructed a multiple alignment of eight Yersinia genomes using Mauve software to identify 78 conserved segments that are internally free from genome rearrangement. Based on the alignment, we applied Bayesian statistical methods to infer the phylogenetic inversion history of Yersinia. The sampling of genome arrangement reconstructions contains seven parsimonious tree topologies, each having different histories of 79 inversions. Topologies with a greater number of inversions also exist, but were sampled less frequently. The inversion phylogenies agree with results suggested by SNP patterns. We then analyzed reconstructed inversion histories to identify patterns of rearrangement. We confirm an over-representation of "symmetric inversions"-inversions with endpoints that are equally distant from the origin of chromosomal replication. Ancestral genome arrangements demonstrate moderate preference for replichore balance in Yersinia. We found that all inversions are shorter than expected under a neutral model, whereas inversions acting within a single replichore are much shorter than expected. We also found evidence for a canonical configuration of the origin and terminus of replication. Finally, breakpoint reuse analysis reveals that inversions with endpoints proximal to the origin of DNA replication are nearly three times more frequent. Our findings

  1. 鼠疫、布氏菌、炭疽活疫苗浓度测定通用参考品的研制%Preparation of universal national reference materials for determining the concentrations of plague, brucellosis and anthrax vaccine

    Institute of Scientific and Technical Information of China (English)

    魏东; 尤明强; 裴明玉; 庄新海; 翟雷; 魏然; 王国治; 李恪梅

    2015-01-01

    Objective To establish a universal national reference materials for determining the concentrations of plague, brucellosis and anthrax vaccine. Methods Firstly, absorbance of universal national reference materials were established. Secondly, correlation between absorbance of universal national reference materials and concentrations ofthreekinds of vaccine was studied using respective national reference material. The universal references were prepared. The stability of the references was tested by measuring absorbance. Finally, the universal reference materials were compared with old reference materials by three professional laboratories. Results Absorbance of universal national reference materials were 0.350, 0.494 and 0.665. The relationship between absorbance of universal national reference materials and the concentrations ofthreekinds of vaccine was determined. Reference materials were successfully established. The reference materials stored at 4℃ were stable. By measuring three batches of each vaccine with two kinds of reference materials, the result errors were less than 2.0%. Conclusion A set of universal national reference materials for determining the concentrations of plague, brucellosis and anthrax vaccine is established.%目的将现用鼠疫、布氏菌、炭疽活疫苗3套浓度测定参考品整合成一套通用参考品。  方法确定通用参考品吸光度值,从3套鼠疫、布氏菌及炭疽疫苗浓度测定用参考品共9个浓度中选取代表性3个浓度参考品;利用现用3种活疫苗浓度测定用参考品的线性方程,计算通用参考品所代表各种疫苗的浓度;制备参考品并进行质量控制;观察参考品的长期稳定性;组织3个实验室进行协作验证。  结果确定通用参考品吸光度值为0.350、0.494、0.665;确定通用参考品所代表各种疫苗浓度;完成通用参考品的制备,各项检定符合规定;对4℃冷藏保存参考品进

  2. Constrained-path quantum Monte Carlo approach for non-yrast states within the shell model

    Energy Technology Data Exchange (ETDEWEB)

    Bonnard, J. [INFN, Sezione di Padova, Padova (Italy); LPC Caen, ENSICAEN, Universite de Caen, CNRS/IN2P3, Caen (France); Juillet, O. [LPC Caen, ENSICAEN, Universite de Caen, CNRS/IN2P3, Caen (France)

    2016-04-15

    The present paper intends to present an extension of the constrained-path quantum Monte Carlo approach allowing to reconstruct non-yrast states in order to reach the complete spectroscopy of nuclei within the interacting shell model. As in the yrast case studied in a previous work, the formalism involves a variational symmetry-restored wave function assuming two central roles. First, it guides the underlying Brownian motion to improve the efficiency of the sampling. Second, it constrains the stochastic paths according to the phaseless approximation to control sign or phase problems that usually plague fermionic QMC simulations. Proof-of-principle results in the sd valence space are reported. They prove the ability of the scheme to offer remarkably accurate binding energies for both even- and odd-mass nuclei irrespective of the considered interaction. (orig.)

  3. NASA and USGS invest in invasive species modeling to evaluate habitat for Africanized Honey Bees

    Science.gov (United States)

    2009-01-01

    Invasive non-native species, such as plants, animals, and pathogens, have long been an interest to the U.S. Geological Survey (USGS) and NASA. Invasive species cause harm to our economy (around $120 B/year), the environment (e.g., replacing native biodiversity, forest pathogens negatively affecting carbon storage), and human health (e.g., plague, West Nile virus). Five years ago, the USGS and NASA formed a partnership to improve ecological forecasting capabilities for the early detection and containment of the highest priority invasive species. Scientists from NASA Goddard Space Flight Center (GSFC) and the Fort Collins Science Center developed a longterm strategy to integrate remote sensing capabilities, high-performance computing capabilities and new spatial modeling techniques to advance the science of ecological invasions [Schnase et al., 2002].

  4. Znu is the predominant zinc importer in Yersinia pestis during in vitro growth but is not essential for virulence.

    Science.gov (United States)

    Desrosiers, Daniel C; Bearden, Scott W; Mier, Ildefonso; Abney, Jennifer; Paulley, James T; Fetherston, Jacqueline D; Salazar, Juan C; Radolf, Justin D; Perry, Robert D

    2010-12-01

    Little is known about Zn homeostasis in Yersinia pestis, the plague bacillus. The Znu ABC transporter is essential for zinc (Zn) uptake and virulence in a number of bacterial pathogens. Bioinformatics analysis identified ZnuABC as the only apparent high-affinity Zn uptake system in Y. pestis. Mutation of znuACB caused a growth defect in Chelex-100-treated PMH2 growth medium, which was alleviated by supplementation with submicromolar concentrations of Zn. Use of transcriptional reporters confirmed that Zur mediated Zn-dependent repression and that it can repress gene expression in response to Zn even in the absence of Znu. Virulence testing in mouse models of bubonic and pneumonic plague found only a modest increase in survival in low-dose infections by the znuACB mutant. Previous studies of cluster 9 (C9) transporters suggested that Yfe, a well-characterized C9 importer for manganese (Mn) and iron in Y. pestis, might function as a second, high-affinity Zn uptake system. Isothermal titration calorimetry revealed that YfeA, the solute-binding protein component of Yfe, binds Mn and Zn with comparably high affinities (dissociation constants of 17.8 ± 4.4 nM and 6.6 ± 1.2 nM, respectively), although the complete Yfe transporter could not compensate for the loss of Znu in in vitro growth studies. Unexpectedly, overexpression of Yfe interfered with the znu mutant's ability to grow in low concentrations of Zn, while excess Zn interfered with the ability of Yfe to import iron at low concentrations; these results suggest that YfeA can bind Zn in the bacterial cell but that Yfe is incompetent for transport of the metal. In addition to Yfe, we have now eliminated MntH, FetMP, Efe, Feo, a substrate-binding protein, and a putative nickel transporter as the unidentified, secondary Zn transporter in Y. pestis. Unlike other bacterial pathogens, Y. pestis does not require Znu for high-level infectivity and virulence; instead, it appears to possess a novel class of transporter

  5. Beyond simple linear mixing models: process-based isotope partitioning of ecological processes.

    Science.gov (United States)

    Ogle, Kiona; Tucker, Colin; Cable, Jessica M

    2014-01-01

    Stable isotopes are valuable tools for partitioning the components contributing to ecological processes of interest, such as animal diets and trophic interactions, plant resource use, ecosystem gas fluxes, streamflow, and many more. Stable isotope data are often analyzed with simple linear mixing (SLM) models to partition the contributions of different sources, but SLM models cannot incorporate a mechanistic understanding of the underlying processes and do not accommodate additional data associated with these processes (e.g., environmental covariates, flux data, gut contents). Thus, SLM models lack predictive ability. We describe a process-based mixing (PBM) model approach for integrating stable isotopes, other data sources, and process models to partition different sources or process components. This is accomplished via a hierarchical Bayesian framework that quantifies multiple sources of uncertainty and enables the incorporation of process models and prior information to help constrain the source-specific proportional contributions, thereby potentially avoiding identifiability issues that plague SLM models applied to "too many" sources. We discuss the application of the PBM model framework to three diverse examples: temporal and spatial partitioning of streamflow, estimation of plant rooting profiles and water uptake profiles (or water sources) with extension to partitioning soil and ecosystem CO2 fluxes, and reconstructing animal diets. These examples illustrate the advantages of the PBM modeling approach, which facilitates incorporation of ecological theory and diverse sources of information into the mixing model framework, thus enabling one to partition key process components across time and space. PMID:24640543

  6. Plane answers to complex questions the theory of linear models

    CERN Document Server

    Christensen, Ronald

    1987-01-01

    This book was written to rigorously illustrate the practical application of the projective approach to linear models. To some, this may seem contradictory. I contend that it is possible to be both rigorous and illustrative and that it is possible to use the projective approach in practical applications. Therefore, unlike many other books on linear models, the use of projections and sub­ spaces does not stop after the general theory. They are used wherever I could figure out how to do it. Solving normal equations and using calculus (outside of maximum likelihood theory) are anathema to me. This is because I do not believe that they contribute to the understanding of linear models. I have similar feelings about the use of side conditions. Such topics are mentioned when appropriate and thenceforward avoided like the plague. On the other side of the coin, I just as strenuously reject teaching linear models with a coordinate free approach. Although Joe Eaton assures me that the issues in complicated problems freq...

  7. Plasmid composition and virulence-associated factors of Yersinia pestis isolates from a plague outbreak at the Paraíba State, Brazil Composição plasmidial e fatores associados à virulência em cepas de Yersinia pestis de um surto de peste no Estado da Paraíba, Brasil

    Directory of Open Access Journals (Sweden)

    Nilma Cintra Leal

    1989-10-01

    Full Text Available Pathogenic Yersinia pestis isolates were collected during a plague outbreak at the Paraiba State in 1986. The Y. pestis isolates were investigated for the presence of virulence-associated factors and plasmid content. All strains analysed were proficient in the expression of the VW and fraction 1 antigens, pigment adsorption and pesticin-fibronolysin-coagulase production. A similar plasmid profile composed by four plasmid with molecular weight of 60, 44, 14.9, and 6.4 Megadaltons (MD was found in all strains. DNA cleavage with EcoRI restriction enzyme further demonstrated the uniform plasmid content of the Y. pestis isolates. Seven additional Y. pestis strains, previously isolated in the same region but in an endemic state, showed the same plasmid fingerprint. The lack of any detectable difference between epidemic and endemic isolates as well as the value of plasmid fingerprints in epidemiology of Y. pestis is discussed.Cepas patogênicas de Yersinia pestis foram coletadas durante um surto de peste no Estado da Paraíba em 1986. Os isolados de Y. pestis foram analisados quanto a presença de fatores associados à virulência e conteúdo plasmidial. Todas as linhagens analisadas foram proficientes na expressão dos antígenos VW e fração 1, além de possuírem capacidade de adsorção de pigmentos e produção de pesticina-fibrinolisina-coagulase. Um perfil plasmidial semelhante composto por quatro plasmídeos com peso molecular de 60, 44, 14.9, e 6.4 MD foi encontrado em todas as linhagens. A clivagem do DNA plasmidial com a enzima de restrição EcoRI demonstrou o conteúdo plasmidial uniforme dos isolados de Y. pestis. Sete outras linhagens de Y. pestis, isoladas previamente no mesmo local mas em condição endêmica, mostraram o mesmo perfil plasmidial. A falta de diferenças entre os isolados epidêmicos e endêmicos assim como o uso do perfil plasmidial na epidemiologic de Y. pestis e discutida.

  8. Discussion of shanghanlun Chapter Han at Critical Disease Plague,Medical Star was Born Informed Opinion——Shanghan Zabing Lun Birth%伤寒评论话:第1章 汉祚岌岌病疫疠,医星冉冉诞宏论——《伤寒杂病论》的诞生

    Institute of Scientific and Technical Information of China (English)

    梁华龙

    2012-01-01

    目的:用普通人也能读懂的白话文阐述《伤寒论》成书的历史文化背景、学术渊源风貌、版本流传情况.方法:从东汉末年的社会、自然条件和张仲景家族兴衰及其个人习医、诊治经历等方面入手,参阅《汉书》及《伤寒论序》,以通俗的语言概述《伤寒论》的诞生过程.结果:《黄帝内经》《难经》《汤液经》《易经》等先哲们的理论成果、特殊的时代背景和疫疠流行等严峻现实、张仲景丰厚的临证经验及高尚的道德观念促成了《伤寒论》的诞生.结论:《伤寒论》是一部集理、法、方、药、护为一体的中医学经典著作,对中医理论发展和临证诊治有着重要指导作用.%Objective:Ordinary people can understand the historical and cultural background academic style vernacular the book of version of the spread of treatise on Febrile Diseases. Methods; From the late Eastern Han Dynasty society, natural condition and the Zhang Zhongjing family prosperity and individual to study medicine, diagnosis and treatment experience of aspects, refer to the "Han" and "Treatise on order" ,with Popular Language Overview "Treatise on the" birth process. Results;Huangdineijing Nanjing,tangyijing, yi-jing philosophers theories,special time background and plague epidemic and grim reality,Zhang Zhongjing rich clinical experience and high moral values contributed to the birth of treatise on Febrile. Conclusion-.Treatise on Febrile is a collection of science, law, medicine, nursing,as one of the traditional Chinese Medicine Classics,on the development of TCM theory and clinical treatment has an important role in guiding.

  9. Sampling plagues; vital aspect in rice comprehensive protection.

    Directory of Open Access Journals (Sweden)

    Rafael Meneses

    2013-12-01

    Full Text Available Food production must be carried out using and maximizing the knowledge and the available technologies, however, one of the main limiting factors of agricultural production and crop quality are the pests and the diseases that attack the cultures from which plants start to grow until their harvest, and even in storage. The periodic sampling in the field generate information regarding the presence of pests, their population density, culture conditions, climatic variables and the presence and activity of natural enemies. Sampling methods vary according to the crop and phenological stage, as well as pests to be sampled. Within the basic components of Integrated Pest Management (IPM is sampling or monitoring of pests, whose main objective is: "To determine when and what action should be made". The determination of the population of pests is a need for phytosanitary control program of any crop. Mechanical Compliance of phytosanitary measures at specified periods according to the needs always leads to wasteful spending, in work, instruments and environmental pollution.

  10. An American plague: Pro-market believers in health policy

    Science.gov (United States)

    de Kervasdoué, Jean

    2015-01-01

    Although American health policy debates address similar problems to other developed nations, it has factual and ideological specificities. I agree with Chinitz and Rodwin on the dominance of micro-economics thinking. However, I am not certain that learning from management theory or modifying medical education will be powerful enough to change the system. The vested interests of the stakeholders are too powerful, the more so when they are supported by economists who ideologically reinforce them and by neglecting the fact that the basic premises of market ideology are false when applied to medical care. There is enough empirical evidence to support that but, apparently, these facts do not dent these beliefs. PMID:25674574

  11. The abundance threshold for plague as a critical percolation phenomenon

    DEFF Research Database (Denmark)

    Davis, S; Trapman, P; Leirs, H;

    2008-01-01

    Percolation theory is most commonly associated with the slow flow of liquid through a porous medium, with applications to the physical sciences 1 . Epidemiological applications have been anticipated for disease systems where the host is a plant or volume of soil 2, 3 , and hence is fixed in space...... thresholds, such as those for epidemic viral infections in African lions (Panthera leo), and of other disease systems such as bovine tuberculosis (caused by Mycobacterium bovis) in badgers (Meles meles)....

  12. Does MFN Free Riding Plague the Information Technology Agreement?

    OpenAIRE

    Sato, Hitoshi

    2014-01-01

    The Information Technology Agreement (ITA), enacted in 1997 as one of a few World Trade Organization (WTO) agreements realized after the Uruguay Round, lifted tariffs on a broad range of IT products such as telecommunication equipment and computers. As part of the General Agreement on Tariffs and Trade (GATT)/WTO system, the ITA is built on the most-favored nation (MFN) principle. However, since participation is not mandatory, any WTO member country can potentially free ride on the agreement....

  13. A curve of thresholds governs plague epizootics in Central Asia

    DEFF Research Database (Denmark)

    Reijniers, Jonas; Davis, Stephen; Begon, Mike;

    2012-01-01

    (mainly Xenopsylla spp.) abundances, resulting in a combined threshold curve with hyperbolic shape. This shape implies compensation between host and vector abundances in permitting infection, which has important implications for disease control. Realistic joint thresholds, supported by data, should...

  14. Proposal Pitfalls Plaguing Researchers: Can Technical Communicators Make a Difference?

    Science.gov (United States)

    Lemanski, Steve

    2014-01-01

    The facts bear out that the odds are against most scientific researchers and scholars--especially those just starting out--in their attempts to win funding for their research projects through their grant proposals. In this article, the author takes a close look at some of the proposal-related problems and pitfalls that have historically challenged…

  15. In Russia, Corruption Plagues the Higher-Education System

    Science.gov (United States)

    Nemtsova, Anna

    2008-01-01

    From the top down, says the writer, Russia's universities are impoverished by bribery and insider deals large and small. A new president's dorm at Nizhniy Novgorod is one example of what anti-corruption watchdogs say is widespread mismanagement, and in some cases outright corruption, throughout the country's higher-education system. Presidents use…

  16. Duck viral enteritis (duck plague) in North American Waterfowl

    Science.gov (United States)

    Locke, L.N.; Leibovitz, L.; Herman, C.M.; Walker, J.W.

    1968-01-01

    This paper briefly reviews the status of DVE among wild waterfowl in North America and describes some of the characteristic lesions associated with this disease. The paper also mentions some of the work which has been undertaken to learn more about the status of DVE in North America.

  17. Torture--a plague to the world-society.

    Science.gov (United States)

    Genefke, I; Marcussen, H; Rasmussen, O V

    2000-06-01

    In this article the authors discussed about government-sanctioned torture, methods of torture, diagnosis of torture along with its modern history, the effect of torture, post-traumatic stress disorder in torture survivors, prevention of torture, impunity and entered into their conclusion based upon more than 20 years of professional medical and psychological work against torture. PMID:11002638

  18. Remote sensing and geographic information systems in the spatial temporal dynamics modeling of infectious diseases

    Institute of Scientific and Technical Information of China (English)

    GONG; Peng

    2006-01-01

    Similar to species immigration or exotic species invasion, infectious disease transmission is strengthened due to the globalization of human activities. Using schistosomiasis as an example, we propose a conceptual model simulating the spatio-temporal dynamics of infectious diseases. We base the model on the knowledge of the interrelationship among the source, media, and the hosts of the disease. With the endemics data of schistosomiasis in Xichang, China, we demonstrate that the conceptual model is feasible; we introduce how remote sensing and geographic information systems techniques can be used in support of spatio-temporal modeling; we compare the different effects caused to the entire population when selecting different groups of people for schistosomiasis control. Our work illustrates the importance of such a modeling tool in supporting spatial decisions. Our modeling method can be directly applied to such infectious diseases as the plague, lyme disease, and hemorrhagic fever with renal syndrome. The application of remote sensing and geographic information systems can shed light on the modeling of other infectious disease and invasive species studies.

  19. Adaptive time stepping algorithm for Lagrangian transport models: Theory and idealised test cases

    Science.gov (United States)

    Shah, Syed Hyder Ali Muttaqi; Heemink, Arnold Willem; Gräwe, Ulf; Deleersnijder, Eric

    2013-08-01

    Random walk simulations have an excellent potential in marine and oceanic modelling. This is essentially due to their relative simplicity and their ability to represent advective transport without being plagued by the deficiencies of the Eulerian methods. The physical and mathematical foundations of random walk modelling of turbulent diffusion have become solid over the years. Random walk models rest on the theory of stochastic differential equations. Unfortunately, the latter and the related numerical aspects have not attracted much attention in the oceanic modelling community. The main goal of this paper is to help bridge the gap by developing an efficient adaptive time stepping algorithm for random walk models. Its performance is examined on two idealised test cases of turbulent dispersion; (i) pycnocline crossing and (ii) non-flat isopycnal diffusion, which are inspired by shallow-sea dynamics and large-scale ocean transport processes, respectively. The numerical results of the adaptive time stepping algorithm are compared with the fixed-time increment Milstein scheme, showing that the adaptive time stepping algorithm for Lagrangian random walk models is more efficient than its fixed step-size counterpart without any loss in accuracy.

  20. A History of Urban Planning and Infectious Diseases: Colonial Senegal in the Early Twentieth Century

    Directory of Open Access Journals (Sweden)

    Liora Bigon

    2012-01-01

    Full Text Available This paper deals with the spatial implications of the French sanitary policies in early colonial urban Senegal. It focuses on the French politics of residential segregation following the outbreak of the bubonic plague in Dakar in 1914, and their precedents in Saint Louis. These policies can be conceived as most dramatic, resulting in a displacement of a considerable portion of the indigenous population, who did not want or could not afford to build à l’européen, to the margins of the colonial city. Aspects of residential segregation are analysed here through the perspective of cultural history and history of colonial planning and architecture, in contrast to the existing literature on this topic. The latter dilates on the statutory policies of the colonial authorities facing the 1914 plague in Dakar, the plague's sociopolitical implications, and the colonial politics of public health there. In the light of relevant historiography, and a variety of secondary and primary sources, this paper exposes the contradictions that were inherent in the French colonial regime in West Africa. These contradictions were wisely used by the African agency, so that such a seemingly urgent segregationist project was actually never accomplished.

  1. 鸭瘟强毒株和疫苗株对雏鸭IFN-γ基因表达的影响%Dynamics of IFN-γ mRNA Expression in Ducks Induced by Duck Plague Virus and Attenuated Virus

    Institute of Scientific and Technical Information of China (English)

    谢秀兰; 杨发龙; 李阳友; 马小明; 岳华

    2011-01-01

    本试验旨在探讨不同毒力的鸭瘟病毒(DPV)感染对雏鸭INF-γ mRNA表达水平的影响,为DPV的感染与免疫机制提供理论依据.应用实时荧光定量PCR技术,对接种了鸭瘟强毒株和疫苗株的雏鸭肝脏及外周血淋巴细胞(PBL)中IFN-γmRNA的表达水平及鸭瘟病毒(DPV)的荷载量进行动态定量监测.结果表明:①感染鸭瘟强毒后,IFN-γ mRNA在肝脏中的表达没有明显规律,PBL中IFN-γ mRNA表达水平很高,在此期间(1~12 h),病毒DNA量很少.IFN-γ mRNA表达量在6h后大幅下降,直到144 h都非常低,而病毒的载量逐渐增大,至144 h时达到峰值.②接种弱毒疫苗后,肝脏中IFN-γ mRNA表达水平较高且稳定,至12 h达到顶峰,约比对照高出8倍.PBL中IFN-γ mRNA表达量较低且不稳定.弱毒DNA荷载量稳定上升,但载量约比强毒低两个数量级.病毒DNA在PBL检测不到.IFN-γ在抵抗鸭瘟强毒中发挥了重要作用;IFN-γ在肝脏中高水平的表达可能是鸭瘟疫苗的免疫机制之一.%To understand the mechanisms of DPV infection and immunity,the IFN-γ mRNA expression was investigated after infection with virulent and attenuated duck plague virus. The mRNA levels of IFN-γ in liver and PBL were evaluated dynamically after inoculation with virulent and attenuated DPV respectively by real-time PCR. The virus loads were also assessed. Results:①After infection by virulent DPV, IFN-γ mRNA levels in liver didn't show regulatory changes while high level of IFN-γ mRNA levels in PBL and few virus DNA could be detected in the early stage of infection (1-12 h). IFN-γ mRNA expression decreased dramatically after 6 h post infection and persisted in a very low level until death (144 h). Virus load increased gradually and reached peak at 144 h. ②After vaccination with attenuated DPV strain, there were persist and high levels of IFN-γ mRNA expression in liver, reached peak at 12 h (8 times higher than control). While the level-in PBL was

  2. A New Model for Mix It Up

    Science.gov (United States)

    Holladay, Jennifer

    2009-01-01

    Since 2002, Teaching Tolerance's Mix It Up at Lunch Day program has helped millions of students cross social boundaries and create more inclusive school communities. Its goal is to create a safe, purposeful opportunity for students to break down the patterns of social self-segregation that too often plague schools. Research conducted in 2006 by…

  3. Towards Complete, Geo-Referenced 3d Models from Crowd-Sourced Amateur Images

    Science.gov (United States)

    Hartmann, W.; Havlena, M.; Schindler, K.

    2016-06-01

    Despite a lot of recent research, photogrammetric reconstruction from crowd-sourced imagery is plagued by a number of recurrent problems. (i) The resulting models are chronically incomplete, because even touristic landmarks are photographed mostly from a few "canonical" viewpoints. (ii) Man-made constructions tend to exhibit repetitive structure and rotational symmetries, which lead to gross errors in the 3D reconstruction and aggravate the problem of incomplete reconstruction. (iii) The models are normally not geo-referenced. In this paper, we investigate the possibility of using sparse GNSS geo-tags from digital cameras to address these issues and push the boundaries of crowd-sourced photogrammetry. A small proportion of the images in Internet collections (≍ 10 %) do possess geo-tags. While the individual geo-tags are very inaccurate, they nevertheless can help to address the problems above. By providing approximate geo-reference for partial reconstructions they make it possible to fuse those pieces into more complete models; the capability to fuse partial reconstruction opens up the possibility to be more restrictive in the matching phase and avoid errors due to repetitive structure; and collectively, the redundant set of low-quality geo-tags can provide reasonably accurate absolute geo-reference. We show that even few, noisy geo-tags can help to improve architectural models, compared to puristic structure-from-motion only based on image correspondence.

  4. Incidência de pragas e doenças em agroecossistemas de café orgânico de agricultores familiares em Poço Fundo-MG Incidence of plagues and diseases in agroecossystems of organic coffee of familiar farmers in Poço Fundo-MG

    Directory of Open Access Journals (Sweden)

    Márcia Martins

    2004-12-01

    2002, de 2.010 Kg ha-1.Having as an aim the determination of insect plagues, Leucoptera coffeella (GUÉRIN-MENÉVILLE, 1842 and Hypothenemus hampei (FERRARI, 1867 and diseases incidence Hemileia vastatrix (BERK e BROOME, 1869 and Cercospora coffeicola (BERK e CURTIS, 1880 during the period from January of 2001 to December of 2002, three agroecosystems with production of organic coffee conducted by familiar farmers of the city of Poço Fundo-MG were selected. The agroecosystem I possesses 2.200 plants of the cultivar 'Red Catuai' spaced 2,5 x 1,3 m (0,72 ha. The agroecosystem II has 2.000 plants ('Red Catuai' spaced 2,8 x 1,0 m (0,56 ha. The agroecosystem III possesses 1.100 feet ('Yellow Icatu' spaced 3,0 x 0,9 m (0,36 ha. The determination of the incidence of L. coffeella, C. coffeicola and H. vastatrix was accomplished starting from monthly surveys. The determination of the infection for C. coffeicola in fruits was accomplished in the months of April, May and June of 2001 and 2002. The survey of the infestation by H. hampei was accomplished from January to June/July of each year. It was determined that the infestation by L. coffeella has reached over 20% in the upper third (mainly during the dry period. The infestation by H. hampei has reached the damage level only in the agroecosystem I on 2001 and agroecosystem III on 2002. The infection by H. vastatrix in the agroecosystem III did not reach the damage level due to the tolerance of the cultivar ('Yellow Icatu' to the infection by this fungus, however, the agroecosystem I and II ('Red Catuai' the infection in the field exceeded 10% (dry period. The infection by C. coffeicola in leaves and fruits reached high levels (dry period. The productivity of the agroecosystem I was 510 Kg ha-1 on 2001 and 2.340 Kg ha-1 on 2002, in the agroecosystem II, it was 420 Kg ha-1 on 2001 and 1.290 Kg ha-1 on 2002, and in the agroecosystem III, it was practically zero on 2001 and 2.010 Kg ha-1 on 2002.

  5. Modeling Model Slicers

    OpenAIRE

    Blouin A.; Combemale B.; Baudry B.; Beaudoux O.

    2011-01-01

    International audience Among model comprehension tools, model slicers are tools that extract a subset from a model, for a specific purpose. Model slicers are tools that let modelers rapidly gather relevant knowledge from large models. However, existing slicers are dedicated to one modeling language. This is an issue when we observe that new domain specific modeling languages (DSMLs), for which we want slicing abilities, are created almost on a daily basis. This paper proposes the Kompren l...

  6. About the Properties of a Modified Generalized Beverton-Holt Equation in Ecology Models

    Directory of Open Access Journals (Sweden)

    M. De La Sen

    2008-01-01

    Full Text Available This paper is devoted to the study of a generalized modified version of the well-known Beverton-Holt equation in ecology. The proposed model describes the population evolution of some species in a certain habitat driven by six parametrical sequences, namely, the intrinsic growth rate (associated with the reproduction capability, the degree of sympathy of the species with the habitat (described by a so-called environment carrying capacity, a penalty term to deal with overpopulation levels, the harvesting (fishing or hunting regulatory quota, or related to use of pesticides when fighting damaging plagues, and the independent consumption which basically quantifies predation. The independent consumption is considered as a part of a more general additive disturbance which also potentially includes another extra additive disturbance term which might be attributed to net migration from or to the habitat or modeling measuring errors. Both potential contributions are included for generalization purposes in the proposed modified generalized Beverton-Holt equation. The properties of stability and boundedness of the solution sequences, equilibrium points of the stationary model, and the existence of oscillatory solution sequences are investigated. A numerical example for a population of aphids is investigated with the theoretical tools developed in the paper.

  7. Deriving a model for influenza epidemics from historical data.

    Energy Technology Data Exchange (ETDEWEB)

    Ray, Jaideep; Lefantzi, Sophia

    2011-09-01

    In this report we describe how we create a model for influenza epidemics from historical data collected from both civilian and military societies. We derive the model when the population of the society is unknown but the size of the epidemic is known. Our interest lies in estimating a time-dependent infection rate to within a multiplicative constant. The model form fitted is chosen for its similarity to published models for HIV and plague, enabling application of Bayesian techniques to discriminate among infectious agents during an emerging epidemic. We have developed models for the progression of influenza in human populations. The model is framed as a integral, and predicts the number of people who exhibit symptoms and seek care over a given time-period. The start and end of the time period form the limits of integration. The disease progression model, in turn, contains parameterized models for the incubation period and a time-dependent infection rate. The incubation period model is obtained from literature, and the parameters of the infection rate are fitted from historical data including both military and civilian populations. The calibrated infection rate models display a marked difference in which the 1918 Spanish Influenza pandemic differed from the influenza seasons in the US between 2001-2008 and the progression of H1N1 in Catalunya, Spain. The data for the 1918 pandemic was obtained from military populations, while the rest are country-wide or province-wide data from the twenty-first century. We see that the initial growth of infection in all cases were about the same; however, military populations were able to control the epidemic much faster i.e., the decay of the infection-rate curve is much higher. It is not clear whether this was because of the much higher level of organization present in a military society or the seriousness with which the 1918 pandemic was addressed. Each outbreak to which the influenza model was fitted yields a separate set of

  8. The figure of the doctor and the science of medicine through Boccaccio's "Decameron".

    Science.gov (United States)

    Sgouridou, Maria

    2014-03-01

    In the person of Boccaccio the humanism of Florence found its major representative. In 1358 he completed his great work, The Decameron, begun some ten years earlier. Considered the prelude to the new spirit that was to be manifested by the Renaissance, it was written in the spirit of a human-centred era. In the tales of The Decameron, based on events occurring during the plague at Florence of 1348, Boccaccio provides a detailed outline of how medical events were viewed at a time of transition from the Middle Ages to the new age of change. The Decameron opens with a description of the Bubonic Plague (Black Death). Boccaccio knows that it started in the East, and attributes it either to the influence of heavenly bodies or to God's anger over the wicked deeds of men. But the symptoms of the plague are not like those in the East, where he has heard that a sudden gush of blood from the nose is a sure sign of impending death. Instead, there are swellings, the buboes, in the groin and under the armpit, growing to the size of a small apple or an egg, then large purple or black spots on other parts of the body, and death soon afterwards. This leads to the story of a group of seven young women and three young men who fled from plague-ridden Florence to a villa outside the city walls. To pass the time, they organized themselves so that each person at night has to amuse the others by telling a story. The stories, told over ten days, contain dramatic and or humorous, elements, and many refer in one way or another to the way illness was conceived and managed in those times.

  9. Emulating Multiple Inheritance in Fortran 2003/2008

    Directory of Open Access Journals (Sweden)

    Karla Morris

    2015-01-01

    in Fortran 2003. The design unleashes the power of the associated class relationships for modeling complicated data structures yet avoids the ambiguities that plague some multiple inheritance scenarios.

  10. The 3SPACE digitizer: A new input device for solid geometry modeling

    Science.gov (United States)

    Scully, J.

    1984-01-01

    The 3SPACE Digitizer is a derivation of SPASYN, which is a patented magnetic transducing system offering an accurate method of calculating the location of one object relative to another. SPASYN uses low-frequency magnetic fields to measure both the position and orientation of its sensor relative to its transmitter. The 3SPACE Digitizer unit consists of a system's electronics unit, a model table, a stylus, and a keypad. In operation, the 3SPACE Digitizer determines the X, Y, Z coordinates of any point located on a low-conductive, three-dimensional model. This data, along with the orientation of the Digitizer's stylus, is immediately available for transmission to a host computer or graphics terminal. Digitization is effected by touching the point to be measured with the tip of a handheld stylus. The 3SPACE Digitizer presents new opportunities for interacting with computers in a large number of engineering and scientific applications. Developed from proven military technology, the 3SPACE Digitizer significantly simplifies three-dimensional digitization and overcomes many of the problems that once plagued such procedures. Its ability to digitize solid objects makes it a valuable new tool for computer-aided design and manufacturing.

  11. Bayesian Fundamentalism or Enlightenment? On the explanatory status and theoretical contributions of Bayesian models of cognition.

    Science.gov (United States)

    Jones, Matt; Love, Bradley C

    2011-08-01

    The prominence of Bayesian modeling of cognition has increased recently largely because of mathematical advances in specifying and deriving predictions from complex probabilistic models. Much of this research aims to demonstrate that cognitive behavior can be explained from rational principles alone, without recourse to psychological or neurological processes and representations. We note commonalities between this rational approach and other movements in psychology - namely, Behaviorism and evolutionary psychology - that set aside mechanistic explanations or make use of optimality assumptions. Through these comparisons, we identify a number of challenges that limit the rational program's potential contribution to psychological theory. Specifically, rational Bayesian models are significantly unconstrained, both because they are uninformed by a wide range of process-level data and because their assumptions about the environment are generally not grounded in empirical measurement. The psychological implications of most Bayesian models are also unclear. Bayesian inference itself is conceptually trivial, but strong assumptions are often embedded in the hypothesis sets and the approximation algorithms used to derive model predictions, without a clear delineation between psychological commitments and implementational details. Comparing multiple Bayesian models of the same task is rare, as is the realization that many Bayesian models recapitulate existing (mechanistic level) theories. Despite the expressive power of current Bayesian models, we argue they must be developed in conjunction with mechanistic considerations to offer substantive explanations of cognition. We lay out several means for such an integration, which take into account the representations on which Bayesian inference operates, as well as the algorithms and heuristics that carry it out. We argue this unification will better facilitate lasting contributions to psychological theory, avoiding the pitfalls

  12. Modeling Model Uncertainty

    OpenAIRE

    Onatski, Alexei; Williams, Noah

    2003-01-01

    Recently there has been much interest in studying monetary policy under model uncertainty. We develop methods to analyze different sources of uncertainty in one coherent structure useful for policy decisions. We show how to estimate the size of the uncertainty based on time series data, and incorporate this uncertainty in policy optimization. We propose two different approaches to modeling model uncertainty. The first is model error modeling, which imposes additional structure on the errors o...

  13. A case study to quantify prediction bounds caused by model-form uncertainty of a portal frame

    Science.gov (United States)

    Van Buren, Kendra L.; Hall, Thomas M.; Gonzales, Lindsey M.; Hemez, François M.; Anton, Steven R.

    2015-01-01

    Numerical simulations, irrespective of the discipline or application, are often plagued by arbitrary numerical and modeling choices. Arbitrary choices can originate from kinematic assumptions, for example the use of 1D beam, 2D shell, or 3D continuum elements, mesh discretization choices, boundary condition models, and the representation of contact and friction in the simulation. This work takes a step toward understanding the effect of arbitrary choices and model-form assumptions on the accuracy of numerical predictions. The application is the simulation of the first four resonant frequencies of a one-story aluminum portal frame structure under free-free boundary conditions. The main challenge of the portal frame structure resides in modeling the joint connections, for which different modeling assumptions are available. To study this model-form uncertainty, and compare it to other types of uncertainty, two finite element models are developed using solid elements, and with differing representations of the beam-to-column and column-to-base plate connections: (i) contact stiffness coefficients or (ii) tied nodes. Test-analysis correlation is performed to compare the lower and upper bounds of numerical predictions obtained from parametric studies of the joint modeling strategies to the range of experimentally obtained natural frequencies. The approach proposed is, first, to characterize the experimental variability of the joints by varying the bolt torque, method of bolt tightening, and the sequence in which the bolts are tightened. The second step is to convert what is learned from these experimental studies to models that "envelope" the range of observed bolt behavior. We show that this approach, that combines small-scale experiments, sensitivity analysis studies, and bounding-case models, successfully produces lower and upper bounds of resonant frequency predictions that match those measured experimentally on the frame structure. (Approved for unlimited, public

  14. Business models as models

    NARCIS (Netherlands)

    C. Baden-Fuller; M.S. Morgan

    2010-01-01

    Drawing on research undertaken in the history and philosophy of science, with particular reference to the extensive literature which discusses the use of models in biology and economics, we explore the question ‘Are Business Models useful?’ We point out that they act as various forms of model: to pr

  15. Characterization of errors in a coupled snow hydrology-microwave emission model

    Science.gov (United States)

    Andreadis, K.M.; Liang, D.; Tsang, L.; Lettenmaier, D.P.; Josberger, E.G.

    2008-01-01

    Traditional approaches to the direct estimation of snow properties from passive microwave remote sensing have been plagued by limitations such as the tendency of estimates to saturate for moderately deep snowpacks and the effects of mixed land cover within remotely sensed pixels. An alternative approach is to assimilate satellite microwave emission observations directly, which requires embedding an accurate microwave emissions model into a hydrologic prediction scheme, as well as quantitative information of model and observation errors. In this study a coupled snow hydrology [Variable Infiltration Capacity (VIC)] and microwave emission [Dense Media Radiative Transfer (DMRT)] model are evaluated using multiscale brightness temperature (TB) measurements from the Cold Land Processes Experiment (CLPX). The ability of VIC to reproduce snowpack properties is shown with the use of snow pit measurements, while TB model predictions are evaluated through comparison with Ground-Based Microwave Radiometer (GBMR), air-craft [Polarimetric Scanning Radiometer (PSR)], and satellite [Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E)] TB measurements. Limitations of the model at the point scale were not as evident when comparing areal estimates. The coupled model was able to reproduce the TB spatial patterns observed by PSR in two of three sites. However, this was mostly due to the presence of relatively dense forest cover. An interesting result occurs when examining the spatial scaling behavior of the higher-resolution errors; the satellite-scale error is well approximated by the mode of the (spatial) histogram of errors at the smaller scale. In addition, TB prediction errors were almost invariant when aggregated to the satellite scale, while forest-cover fractions greater than 30% had a significant effect on TB predictions. ?? 2008 American Meteorological Society.

  16. Hijacking of the pleiotropic cytokine interferon-γ by the type III secretion system of Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Claire Gendrin

    Full Text Available Yersinia pestis, the causative agent of bubonic plague, employs its type III secretion system to inject toxins into target cells, a crucial step in infection establishment. LcrV is an essential component of the T3SS of Yersinia spp, and is able to associate at the tip of the secretion needle and take part in the translocation of anti-host effector proteins into the eukaryotic cell cytoplasm. Upon cell contact, LcrV is also released into the surrounding medium where it has been shown to block the normal inflammatory response, although details of this mechanism have remained elusive. In this work, we reveal a key aspect of the immunomodulatory function of LcrV by showing that it interacts directly and with nanomolar affinity with the inflammatory cytokine IFNγ. In addition, we generate specific IFNγ mutants that show decreased interaction capabilities towards LcrV, enabling us to map the interaction region to two basic C-terminal clusters of IFNγ. Lastly, we show that the LcrV-IFNγ interaction can be disrupted by a number of inhibitors, some of which display nanomolar affinity. This study thus not only identifies novel potential inhibitors that could be developed for the control of Yersinia-induced infection, but also highlights the diversity of the strategies used by Y. pestis to evade the immune system, with the hijacking of pleiotropic cytokines being a long-range mechanism that potentially plays a key role in the severity of plague.

  17. [History of human epidemic and endemic diseases in the southwest Indian Ocean].

    Science.gov (United States)

    Gaüzère, B-A; Aubry, P

    2013-05-01

    Smallpox has been known in the Mascarene Islands since 1729, and in 1898, the vaccinogenic and anti-rabies Institute of Tananarive, the future Pasteur Institute of Madagascar, was created to combat it. Cholera first arrived in the Mascarenes in 1819, but did not affect the Comoros Islands and Madagascar until the current pandemic. Bubonic plague has beset the ports of Madagascar and the Mascarenes since 1898. Girard and Robic developed the anti-plague vaccine in 1931 at the Pasteur Institute of Madagascar. The Mascarenes lost their reputation as Eden when malaria arrived in 1841, and this disease remains prominent in Madagascar and Comoros. Leprosy has been known in La Réunion since 1726 and is still very present in Mayotte, Anjouan, and Madagascar. Leptospirosis is a public health problem, except in Madagascar and the Comoros. Dengue, chikungunya, and Rift Valley fever are also present. HIV/AIDS is not a major concern, except in Mauritius, where it was spread by injection drug use, in the Seychelles and in Madagascar's largest cities. Madagascar is the principal site worldwide of chromoblastomycosis, first described there in 1914. PMID:23797833

  18. Resistance of Mice of the 129 Background to Yersinia pestis Maps to Multiple Loci on Chromosome 1.

    Science.gov (United States)

    Tencati, Michael; Tapping, Richard I

    2016-10-01

    Yersinia pestis is a Gram-negative bacterium that is the causative agent of bubonic and pneumonic plague. It is commonly acquired by mammals such as rodents and humans via the bite of an infected flea. We previously reported that multiple substrains of the 129 mouse background are resistant to pigmentation locus-negative (pgm(-)) Yersinia pestis and that this phenotype maps to a 30-centimorgan (cM) region located on chromosome 1. In this study, we have further delineated this plague resistance locus to a region of less than 20 cM through the creation and phenotyping of recombinant offspring arising from novel crossovers in this region. Furthermore, our experiments have revealed that there are at least two alleles in this initial locus, both of which are required for resistance on a susceptible C57BL/6 background. These two alleles work in trans since resistance is restored in offspring possessing one allele contributed by each parent. Our studies also indicated that the Slc11a1 gene (formerly known as Nramp1) located within the chromosome1 locus is not responsible for conferring resistance to 129 mice. PMID:27481241

  19. Business Models as Models

    OpenAIRE

    Baden-Fuller, C.; Morgan, M S

    2010-01-01

    Drawing on research undertaken in the history and philosophy of science, with particular reference to the extensive literature which discusses the use of models in biology and economics, we explore the question ‘Are Business Models useful?’ We point out that they act as various forms of model: to provide means to describe and classify businesses; to operate as sites for scientific investigation; and to act as recipes for creative managers. We argue that studying business models as models is r...

  20. Climate change induced transformations of agricultural systems: insights from a global model

    International Nuclear Information System (INIS)

    Climate change might impact crop yields considerably and anticipated transformations of agricultural systems are needed in the coming decades to sustain affordable food provision. However, decision-making on transformational shifts in agricultural systems is plagued by uncertainties concerning the nature and geography of climate change, its impacts, and adequate responses. Locking agricultural systems into inadequate transformations costly to adjust is a significant risk and this acts as an incentive to delay action. It is crucial to gain insight into how much transformation is required from agricultural systems, how robust such strategies are, and how we can defuse the associated challenge for decision-making. While implementing a definition related to large changes in resource use into a global impact assessment modelling framework, we find transformational adaptations to be required of agricultural systems in most regions by 2050s in order to cope with climate change. However, these transformations widely differ across climate change scenarios: uncertainties in large-scale development of irrigation span in all continents from 2030s on, and affect two-thirds of regions by 2050s. Meanwhile, significant but uncertain reduction of major agricultural areas affects the Northern Hemisphere’s temperate latitudes, while increases to non-agricultural zones could be large but uncertain in one-third of regions. To help reducing the associated challenge for decision-making, we propose a methodology exploring which, when, where and why transformations could be required and uncertain, by means of scenario analysis. (letter)

  1. Long-ranged contributions to solvation free energies from theory and short-ranged models

    Science.gov (United States)

    Remsing, Richard C.; Liu, Shule; Weeks, John D.

    2016-03-01

    Long-standing problems associated with long-ranged electrostatic interactions have plagued theory and simulation alike. Traditional lattice sum (Ewald-like) treatments of Coulomb interactions add significant overhead to computer simulations and can produce artifacts from spurious interactions between simulation cell images. These subtle issues become particularly apparent when estimating thermodynamic quantities, such as free energies of solvation in charged and polar systems, to which long-ranged Coulomb interactions typically make a large contribution. In this paper, we develop a framework for determining very accurate solvation free energies of systems with long-ranged interactions from models that interact with purely short-ranged potentials. Our approach is generally applicable and can be combined with existing computational and theoretical techniques for estimating solvation thermodynamics. We demonstrate the utility of our approach by examining the hydration thermodynamics of hydrophobic and ionic solutes and the solvation of a large, highly charged colloid that exhibits overcharging, a complex nonlinear electrostatic phenomenon whereby counterions from the solvent effectively overscreen and locally invert the integrated charge of the solvated object.

  2. Forced versus coupled dynamics in Earth system modelling and prediction

    Directory of Open Access Journals (Sweden)

    B. Knopf

    2005-01-01

    Full Text Available We compare coupled nonlinear climate models and their simplified forced counterparts with respect to predictability and phase space topology. Various types of uncertainty plague climate change simulation, which is, in turn, a crucial element of Earth System modelling. Since the currently preferred strategy for simulating the climate system, or the Earth System at large, is the coupling of sub-system modules (representing, e.g. atmosphere, oceans, global vegetation, this paper explicitly addresses the errors and indeterminacies generated by the coupling procedure. The focus is on a comparison of forced dynamics as opposed to fully, i.e. intrinsically, coupled dynamics. The former represents a particular type of simulation, where the time behaviour of one complex systems component is prescribed by data or some other external information source. Such a simplifying technique is often employed in Earth System models in order to save computing resources, in particular when massive model inter-comparisons need to be carried out. Our contribution to the debate is based on the investigation of two representative model examples, namely (i a low-dimensional coupled atmosphere-ocean simulator, and (ii a replica-like simulator embracing corresponding components.Whereas in general the forced version (ii is able to mimic its fully coupled counterpart (i, we show in this paper that for a considerable fraction of parameter- and state-space, the two approaches qualitatively differ. Here we take up a phenomenon concerning the predictability of coupled versus forced models that was reported earlier in this journal: the observation that the time series of the forced version display artificial predictive skill. We present an explanation in terms of nonlinear dynamical theory. In particular we observe an intermittent version of artificial predictive skill, which we call on-off synchronization, and trace it back to the appearance of unstable periodic orbits. We also

  3. Evaluating the role of green infrastructures on near-road pollutant dispersion and removal: Modelling and measurement.

    Science.gov (United States)

    Morakinyo, Tobi Eniolu; Lam, Yun Fat; Hao, Song

    2016-11-01

    To enhance the quality of human life in a rapidly urbanized world plagued with high transportation, the masterful contribution of improved urban and local air quality cannot be overemphasized. In order to reduce human exposure to near-road air pollution, several approaches including the installation of roadside structural barriers especially in open street areas, such as city entrances are being applied. In the present study, the air quality around real world and idealized green infrastructures was investigated by means of numerical simulation and a short field measurement campaign. Fair agreement was found between ENVI-met modelled and measured particulate matter's concentration data around a realistic vegetation barrier indicating a fair representation of reality in the model. Several numerical experiments were conducted to investigate the influence of barrier type (vegetation/hedge and green wall) and dimensions on near-road air quality. The results show different horizontal/vertical patterns and magnitudes of upwind and downwind relative concentration (with and without a barrier) depending on wind condition, barrier type and dimension. Furthermore, an integrated dispersion-deposition approach was employed to assess the impact on air quality of near-road vegetation barrier. At last, recommendations to city and urban planners on the implementation of roadside structural barriers were made. PMID:27544646

  4. Evaluating the role of green infrastructures on near-road pollutant dispersion and removal: Modelling and measurement.

    Science.gov (United States)

    Morakinyo, Tobi Eniolu; Lam, Yun Fat; Hao, Song

    2016-11-01

    To enhance the quality of human life in a rapidly urbanized world plagued with high transportation, the masterful contribution of improved urban and local air quality cannot be overemphasized. In order to reduce human exposure to near-road air pollution, several approaches including the installation of roadside structural barriers especially in open street areas, such as city entrances are being applied. In the present study, the air quality around real world and idealized green infrastructures was investigated by means of numerical simulation and a short field measurement campaign. Fair agreement was found between ENVI-met modelled and measured particulate matter's concentration data around a realistic vegetation barrier indicating a fair representation of reality in the model. Several numerical experiments were conducted to investigate the influence of barrier type (vegetation/hedge and green wall) and dimensions on near-road air quality. The results show different horizontal/vertical patterns and magnitudes of upwind and downwind relative concentration (with and without a barrier) depending on wind condition, barrier type and dimension. Furthermore, an integrated dispersion-deposition approach was employed to assess the impact on air quality of near-road vegetation barrier. At last, recommendations to city and urban planners on the implementation of roadside structural barriers were made.

  5. Model Transformations? Transformation Models!

    NARCIS (Netherlands)

    Bézivin, J.; Büttner, F.; Gogolla, M.; Jouault, F.; Kurtev, I.; Lindow, A.

    2006-01-01

    Much of the current work on model transformations seems essentially operational and executable in nature. Executable descriptions are necessary from the point of view of implementation. But from a conceptual point of view, transformations can also be viewed as descriptive models by stating only the

  6. Modelling SDL, Modelling Languages

    Directory of Open Access Journals (Sweden)

    Michael Piefel

    2007-02-01

    Full Text Available Today's software systems are too complex to implement them and model them using only one language. As a result, modern software engineering uses different languages for different levels of abstraction and different system aspects. Thus to handle an increasing number of related or integrated languages is the most challenging task in the development of tools. We use object oriented metamodelling to describe languages. Object orientation allows us to derive abstract reusable concept definitions (concept classes from existing languages. This language definition technique concentrates on semantic abstractions rather than syntactical peculiarities. We present a set of common concept classes that describe structure, behaviour, and data aspects of high-level modelling languages. Our models contain syntax modelling using the OMG MOF as well as static semantic constraints written in OMG OCL. We derive metamodels for subsets of SDL and UML from these common concepts, and we show for parts of these languages that they can be modelled and related to each other through the same abstract concepts.

  7. Developing a test for random number generators using a simulation of the hierarchical Potts diamond model at the critical point

    Science.gov (United States)

    Liberty, Joshua W.

    This dissertation uses the hierarchical q-state Potts model at the critical point to develop a new random number generator test. We start with an exposition of renormalization group approach by means of which one can numerically exactly compute the free energy, specific heat and susceptibility of large, but finite lattices. We then show that generalization of these standard techniques allows one to also compute probability distributions related to the energy and the order parameter. The various computed quantities can be compared with Monte Carlo estimates of the same quantities. We demonstrate that the structure of the hierarchical lattices used allows one to perform the Monte Carlo calculations by direct sampling. This avoids the usual critical slowing down that plagues Monte Carlo calculations at the critical point. As is well known, critical behavior is highly susceptible to perturbations. We expect that flaws of the pseudo random number generator, such as correlations, will cause statistically significant discrepancies between the results of the simulations and the numerically exactly computed results. Details of the computer code generated for these tests are included.

  8. Protective effects of recombinant glycoprotein D based prime boost approach against duck enteritis virus in mice model.

    Science.gov (United States)

    Aravind, S; Kamble, Nitin Machindra; Gaikwad, Satish S; Shukla, Sanjeev Kumar; Saravanan, R; Dey, Sohini; Mohan, C Madhan

    2015-11-01

    Duck virus enteritis, also known as duck plague, is an acute herpes viral infection of ducks caused by duck enteritis virus (DEV). The method of repeated immunization with a live attenuated vaccine has been used for the prevention and control of duck enteritis virus (DEV). However, the incidence of the disease in vaccinated flocks and latency reactivation are the major constraints in the present vaccination programme. The immunogenicity and protective efficacy afforded by intramuscular inoculation of plasmid DNA encoding DEV glycoprotein D (pCDNA-gD) followed by DEV gD expressed in Saccharomyces cerevisia (rgD) was assessed in a murine model. Compared with mice inoculated with DNA (pCDNA-gD) or protein (rgD) only, mice inoculated with the combination of gD DNA and protein had enhanced ELISA antibody titers to DEV and had accelerated clearance of virus following challenge infection. Furthermore, the highest levels of lymphocyte proliferation response, IL-4, IL-12 and IFN-γ production were induced following priming with the DNA vaccine and boosting with the rgD protein. For instance, the specially designed recombinant DEV vector vaccine would be the best choice to use in ducks. It offers an excellent solution to the low vaccination coverage rate in ducks. We expect that the application of this novel vaccine in the near future will greatly decrease the virus load in the environment and reduce outbreaks of DEV in ducks.

  9. Site-occupancy distribution modeling to correct population-trend estimates derived from opportunistic observations

    Science.gov (United States)

    Kery, M.; Royle, J. Andrew; Schmid, H.; Schaub, M.; Volet, B.; Hafliger, G.; Zbinden, N.

    2010-01-01

    Species' assessments must frequently be derived from opportunistic observations made by volunteers (i.e., citizen scientists). Interpretation of the resulting data to estimate population trends is plagued with problems, including teasing apart genuine population trends from variations in observation effort. We devised a way to correct for annual variation in effort when estimating trends in occupancy (species distribution) from faunal or floral databases of opportunistic observations. First, for all surveyed sites, detection histories (i.e., strings of detection-nondetection records) are generated. Within-season replicate surveys provide information on the detectability of an occupied site. Detectability directly represents observation effort; hence, estimating detectablity means correcting for observation effort. Second, site-occupancy models are applied directly to the detection-history data set (i.e., without aggregation by site and year) to estimate detectability and species distribution (occupancy, i.e., the true proportion of sites where a species occurs). Site-occupancy models also provide unbiased estimators of components of distributional change (i.e., colonization and extinction rates). We illustrate our method with data from a large citizen-science project in Switzerland in which field ornithologists record opportunistic observations. We analyzed data collected on four species: the widespread Kingfisher (Alcedo atthis. ) and Sparrowhawk (Accipiter nisus. ) and the scarce Rock Thrush (Monticola saxatilis. ) and Wallcreeper (Tichodroma muraria. ). Our method requires that all observed species are recorded. Detectability was <1 and varied over the years. Simulations suggested some robustness, but we advocate recording complete species lists (checklists), rather than recording individual records of single species. The representation of observation effort with its effect on detectability provides a solution to the problem of differences in effort encountered

  10. SELCO: A model for solar rural electrification in India

    Science.gov (United States)

    Hande, H. Harish

    1999-11-01

    The following thesis presents the concept of a Rural Energy Service Company in India, known as SELCO. The model is being set up as a sustainable proposition for the implementation of solar photovoltaics as a viable alternative to provide reliable home lighting in the rural areas of India. The SELCO approach has already achieved noteworthy social and commercial results. Institutional, policy and operational problems have long plagued the rural electrification programs in India, resulting in thousands of villages without access to electricity. SELCO is a solar energy service company operating in Southern India since 1995, focusing on the enormous untapped market for home lighting where thousands of households have no access to electricity and severe power shortages face those already connected to the electric grid. The Company has installed nearly 2,000 solar home lighting systems. From a modest two employees company in 1995, it has grown to 35 in 1997 and from one office to eight. The hypothesis to be tested in this study is that in rural India, in a market not subsidized by the government, a solar service company with available loans from local banks and cooperatives and with sales, installation, and maintenance personnel in the villages can be successful in introducing photovoltaic systems to provide basic amenities such as lighting and water pumping for the improvement of the quality of life, public health, and the environment. The initial success of SELCO lends considerable evidence to the acceptance of the hypothesis. To accomplish its mission, SELCO works with commercial, retail, and rural development banks with large rural branch networks to stimulate loans to SELCO's customers based on a standard set of attractive financing terms. SELCO through its successful model has convinced the policy makers that a way to increase rural families' access to consumer financing for solar home lighting systems is through the existing financial network available in the

  11. Actant Models

    DEFF Research Database (Denmark)

    Poulsen, Helle

    1996-01-01

    This paper presents a functional modelling method called Actant Modelling rooted in linguistics and semiotics. Actant modelling can be integrated with Multilevel Flow Modelling (MFM) in order to give an interpretation of actants.......This paper presents a functional modelling method called Actant Modelling rooted in linguistics and semiotics. Actant modelling can be integrated with Multilevel Flow Modelling (MFM) in order to give an interpretation of actants....

  12. Modelling the models

    CERN Multimedia

    Anaïs Schaeffer

    2012-01-01

    By analysing the production of mesons in the forward region of LHC proton-proton collisions, the LHCf collaboration has provided key information needed to calibrate extremely high-energy cosmic ray models.   Average transverse momentum (pT) as a function of rapidity loss ∆y. Black dots represent LHCf data and the red diamonds represent SPS experiment UA7 results. The predictions of hadronic interaction models are shown by open boxes (sibyll 2.1), open circles (qgsjet II-03) and open triangles (epos 1.99). Among these models, epos 1.99 shows the best overall agreement with the LHCf data. LHCf is dedicated to the measurement of neutral particles emitted at extremely small angles in the very forward region of LHC collisions. Two imaging calorimeters – Arm1 and Arm2 – take data 140 m either side of the ATLAS interaction point. “The physics goal of this type of analysis is to provide data for calibrating the hadron interaction models – the well-known &...

  13. Modelling Practice

    DEFF Research Database (Denmark)

    Cameron, Ian; Gani, Rafiqul

    2011-01-01

    This chapter deals with the practicalities of building, testing, deploying and maintaining models. It gives specific advice for each phase of the modelling cycle. To do this, a modelling framework is introduced which covers: problem and model definition; model conceptualization; model data...... requirements; model construction; model solution; model verification; model validation and finally model deployment and maintenance. Within the adopted methodology, each step is discussedthrough the consideration of key issues and questions relevant to the modelling activity. Practical advice, based on many...... years of experience is providing in directing the reader in their activities.Traps and pitfalls are discussed and strategies also given to improve model development towards “fit-for-purpose” models. The emphasis in this chapter is the adoption and exercise of a modelling methodology that has proven very...

  14. Model misinterpretation

    OpenAIRE

    Daniel J Kliebenstein

    2012-01-01

    Models of myriad forms are rapidly becoming central to biology. This ranges from statistical models that are fundamental to the interpretation of experimental results to ODE models that attempt to describe the results in a mechanistic format. Models will be more and more essential to biologists but this growing importance requires all model users to become more sophisticated about what is in a model and how that limits the usability of the model. This review attempts to relay the potential pi...

  15. Promoting Models

    Science.gov (United States)

    Li, Qin; Zhao, Yongxin; Wu, Xiaofeng; Liu, Si

    There can be multitudinous models specifying aspects of the same system. Each model has a bias towards one aspect. These models often override in specific aspects though they have different expressions. A specification written in one model can be refined by introducing additional information from other models. The paper proposes a concept of promoting models which is a methodology to obtain refinements with support from cooperating models. It refines a primary model by integrating the information from a secondary model. The promotion principle is not merely an academic point, but also a reliable and robust engineering technique which can be used to develop software and hardware systems. It can also check the consistency between two specifications from different models. A case of modeling a simple online shopping system with the cooperation of the guarded design model and CSP model illustrates the practicability of the promotion principle.

  16. Modeling bacteriophage amplification as a predictive tool for optimized MALDI-TOF MS-based bacterial detection.

    Science.gov (United States)

    Cox, Christopher R; Rees, Jon C; Voorhees, Kent J

    2012-11-01

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a valuable tool for rapid bacterial detection and identification but is limited by the need for relatively high cell count samples, which have been grown under strictly controlled conditions. These requirements can be eliminated by the natural infection of a viable bacterial species of interest with a host-specific phage. This produces a rapid increase in phage protein concentrations in comparison to bacterial concentrations, which can in turn be exploited as a method for signal amplification during MALDI-TOF MS. One drawback to this approach is the requirement for repetitive, time-consuming sample preparation and analysis applied over the course of a phage infection to monitor phage concentrations as a function of time to determine the MALDI-TOF MS detection limit. To reduce the requirement for repeated preparation and analysis, a modified phage therapy model was investigated as a means for predicting the time during a given phage infection when a detectable signal would occur. The modified model used a series of three differential equations composed of predetermined experimental parameters including phage burst size and burst time to predict progeny phage concentrations as a function of time. Using Yersinia pestis with plague diagnostic phage φA1122 and Escherichia coli with phage MS2 as two separate, well-characterized model phage-host pairs, we conducted in silico modeling of the infection process and compared it with experimental infections monitored in real time by MALDI-TOF MS. Significant agreement between mathematically calculated phage growth curves and those experimentally obtained by MALDI-TOF MS was observed, thus verifying this method's utility for significant time and labor reduction.

  17. Nonparametric Modeling of the Anchoring Effect in an Unfolding Bracket Design

    NARCIS (Netherlands)

    Vazquez-Alvarez, R.; Melenberg, B.; van Soest, A.H.O.

    1999-01-01

    Household surveys are often plagued by item non-response on economic variables of interest like income, savings or the amount of wealth. Manski (1989,1994, 1995) shows how, in the presence of such non-response, bounds on conditional quantiles of the variable of interest can be derived, allowing for

  18. [Alexandre Yersin (1863-1943), explorer and a founding scientist of the Pasteur Institutes].

    Science.gov (United States)

    Milleliri, J M

    2014-01-01

    2013 was the year to celebrate Yersin: the 150th anniversary of his birth and the 70th anniversary of his death. Beyond the images usually attached to the memory of this doctor who discovered the bubonic plague bacillus (in Hong Kong in 1894), the author seeks to introduce Yersin, the man, as an explorer curious about his environment rather than a scientist concerned with honors and public recognition. Alexandre Yersin is an atypical figure in the universe of Pasteur, his collaborators, students, and followers. Although he began his career working with Louis Pasteur following the development of the vaccine against rabies, in 1885, the call of the sea led him to quit the laboratory on rue Ulm to, he said, "explore new lands". He worked for the Messageries maritimes merchant shipping company. In Saigon, he met Albert Calmette, who convinced him to join the newly created Colonial Army Medical Corps. In 1892 in Nha-Trang, Yersin set up a bacteriology laboratory in a straw hut; it subsequently became the first Pasteur Institute in Indochina, the starting point of a network of research laboratories. During the bubonic plague epidemic that raged in Hong Kong, Yersin succeeded in isolating its causal agent, surprising even himself by the ease with which he did so. He was 30 years old then, but what could have been the start of a prestigious career, crowned with honors, was spent instead at the service of the local populations. His exploration of the Vietnam highlands gave Yersin the occasion to cultivate and reveal a prodigious eclecticism and his profound humanism. He led three explorations in unknown regions of Annam and contributed to the development of this country by his social, educational, medical, and economic approach, entirely dedicated to aiding the indigenous populations. Yersin never left Vietnam again. He worked as an astronomer and agronomist (introducing the cultivation of cinchona (source of quinine) and rubber trees in the country) - always close to the

  19. [Alexandre Yersin (1863-1943), explorer and a founding scientist of the Pasteur Institutes].

    Science.gov (United States)

    Milleliri, J M

    2014-01-01

    2013 was the year to celebrate Yersin: the 150th anniversary of his birth and the 70th anniversary of his death. Beyond the images usually attached to the memory of this doctor who discovered the bubonic plague bacillus (in Hong Kong in 1894), the author seeks to introduce Yersin, the man, as an explorer curious about his environment rather than a scientist concerned with honors and public recognition. Alexandre Yersin is an atypical figure in the universe of Pasteur, his collaborators, students, and followers. Although he began his career working with Louis Pasteur following the development of the vaccine against rabies, in 1885, the call of the sea led him to quit the laboratory on rue Ulm to, he said, "explore new lands". He worked for the Messageries maritimes merchant shipping company. In Saigon, he met Albert Calmette, who convinced him to join the newly created Colonial Army Medical Corps. In 1892 in Nha-Trang, Yersin set up a bacteriology laboratory in a straw hut; it subsequently became the first Pasteur Institute in Indochina, the starting point of a network of research laboratories. During the bubonic plague epidemic that raged in Hong Kong, Yersin succeeded in isolating its causal agent, surprising even himself by the ease with which he did so. He was 30 years old then, but what could have been the start of a prestigious career, crowned with honors, was spent instead at the service of the local populations. His exploration of the Vietnam highlands gave Yersin the occasion to cultivate and reveal a prodigious eclecticism and his profound humanism. He led three explorations in unknown regions of Annam and contributed to the development of this country by his social, educational, medical, and economic approach, entirely dedicated to aiding the indigenous populations. Yersin never left Vietnam again. He worked as an astronomer and agronomist (introducing the cultivation of cinchona (source of quinine) and rubber trees in the country) - always close to the

  20. Model Warehouse

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper puts forward a new conception:model warehouse,analyzes the reason why model warehouse appears and introduces the characteristics and architecture of model warehouse.Last,this paper points out that model warehouse is an important part of WebGIS.

  1. Model theory

    CERN Document Server

    Chang, CC

    2012-01-01

    Model theory deals with a branch of mathematical logic showing connections between a formal language and its interpretations or models. This is the first and most successful textbook in logical model theory. Extensively updated and corrected in 1990 to accommodate developments in model theoretic methods - including classification theory and nonstandard analysis - the third edition added entirely new sections, exercises, and references. Each chapter introduces an individual method and discusses specific applications. Basic methods of constructing models include constants, elementary chains, Sko

  2. Model error

    OpenAIRE

    Katerina Simons

    1997-01-01

    Modern finance would not have been possible without models. Increasingly complex quantitative models drive financial innovation and the growth of derivatives markets. Models are necessary to value financial instruments and to measure the risks of individual positions and portfolios. Yet when used inappropriately, the models themselves can become an important source of risk. Recently, several well-publicized instances occurred of institutions suffering significant losses attributed to model er...

  3. Model cities

    OpenAIRE

    M Batty

    2007-01-01

    The term ?model? is now central to our thinking about how weunderstand and design cities. We suggest a variety of ways inwhich we use ?models?, linking these ideas to Abercrombie?sexposition of Town and Country Planning which represented thestate of the art fifty years ago. Here we focus on using models asphysical representations of the city, tracing the development ofsymbolic models where the focus is on simulating how functiongenerates form, to iconic models where the focus is on representi...

  4. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics. We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

  5. Event Modeling

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2001-01-01

    The purpose of this chapter is to discuss conceptual event modeling within a context of information modeling. Traditionally, information modeling has been concerned with the modeling of a universe of discourse in terms of information structures. However, most interesting universes of discourse...... are dynamic and we present a modeling approach that can be used to model such dynamics.We characterize events as both information objects and change agents (Bækgaard 1997). When viewed as information objects events are phenomena that can be observed and described. For example, borrow events in a library can...

  6. Modelling Overview

    DEFF Research Database (Denmark)

    Larsen, Lars Bjørn; Vesterager, Johan

    This report provides an overview of the existing models of global manufacturing, describes the required modelling views and associated methods and identifies tools, which can provide support for this modelling activity.The model adopted for global manufacturing is that of an extended enterprise....... One or more units from beyond the network may complement the extended enterprise. The common reference model for this extended enterprise will utilise GERAM (Generalised Enterprise Reference Architecture and Methodology) to provide an architectural framework for the modelling carried out within...

  7. Euro Feast for Estonia - Feast in Time of Plague? / Andres Arrak

    Index Scriptorium Estoniae

    Arrak, Andres, 1958-

    2010-01-01

    Autor leiab, et Eesti Pank ja valitsus peaksid selgitama rahvale euroga liitumise vajadust ajal, mil terve maailm kannatab majanduskriisi all ja euroala riigid ei suuda täita Maastrichti kriteeriume ning euro jaoks on saabunud rasked ajad. Kreeka majandusnäitajatest

  8. Standardization of the dot enzyme-lynked immunosorbent assay (dot-ELISA for experimental plague

    Directory of Open Access Journals (Sweden)

    Silvia M. L. Montenegro

    1993-03-01

    Full Text Available A dot enzyme linked immunosorbent assay (dot-ELISA was previously developed to detect specific antibodies in rabbits sera immunized against FIA protein obtained from Yersina pestis. This antigen was covalently linked onto the surface of dacron (polyethyleneterephthalate. Here, standard conditions are described for the optimization of this procedure: an amount of 20 ng of FIA protein was fixed onto dacron; anti-rabbit IgG peroxidase conjugate diluted 1:8,000 and 30% non-fat instant milk as blocking substance were used throughout the method. This procedure was compared with that employing nitrocellulose as solid-phase which showed to be more sensitive. However, the method based on dacron did not show false positive reactions against non-immunized rabbits sera at low antigen amount and diluted anti-IgG peroxidase conjugate.

  9. SAP R/3 An IT-plague or the answer to the Tailors dream?

    DEFF Research Database (Denmark)

    Koch, Christian

    1999-01-01

    The IT-market of ERP-systems have significantly changed over the last 10 years. At least in Denmark manufacturing enterprises used to close "partner like" collaboration with their IT-supplier, now face mass produced packaged software. This challenges the skills of technology managers, can they co...

  10. The Origin of Plagues : A Research Agenda for the 21st Century

    OpenAIRE

    Krause, Richard M.

    1993-01-01

    Viruses, bacteria, and parasites emerge in both new and old forms to cause epidemics. Old microbes can produce new epidemics because of changes in the life style (including increased international travel) of people and societies. But epidemics occur also as a consequence of new genetic variations in microbes. These various epidemics connect the future with the past, offering lessons for guarding the health of generations to come-lessons learned from diseases such as malaria, tuberculosis, inf...

  11. [Monitoring the Microtus fuscus plague epidemic in Sichuan province during 2000 - 2008.

    DEFF Research Database (Denmark)

    Wang, Li-Mao; Song, Xiao-Yu; Zhu, Xiao-Ping;

    2009-01-01

    epidemic from 2000 to 2008, with the average density as 312.41/ha. 42.57% of the Microtus fuscus were infected by body Fleas. The Fleas Index was 0.88 and the Index for nest Fleas of Microtus fuscus was 55.89. Six kinds of animals were infected by not only the Microtus fuscus but also herd-dog, sand fox......, Tibetan sheep, domestic cats and Cricetulus longicaulatus as well. The positive rate of live Microtus fuscus was 0.32% but 22.99% in the dead Microtus fuscus. The overall positive rate on serological test was 6.70%. There were 4 Sections, 11 species and 19 kinds Fleas identified and carrying 3 kinds...

  12. Bacterial profiling of White Plague Disease in a comparative coral species framework

    OpenAIRE

    Roder, Cornelia; Arif, Chatchanit; Bayer, Till; Aranda, Manuel; Daniels, Camille; Shibl, Ahmed; Chavanich, Suchana; VOOLSTRA, CHRISTIAN R.

    2013-01-01

    Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studie...

  13. Periodic temperature-associated drought/flood drives locust plagues in China

    OpenAIRE

    Zhang, Zhibin; Cazelles, Bernard; Tian, Huidong; Christian Stige, Leif; Bräuning, Achim; Stenseth, Nils Chr

    2008-01-01

    Global warming is currently of great concern. Yet the ecological effects of low-frequency climate variations remain largely unknown. Recent analyses of interdecadal variability in population abundance of the Oriental migratory locust (Locusta migratoria manilensis) in China have revealed negative associations with temperature and positive associations with Yangtze drought and flood frequencies during the past millennium (AD 957-1956). In order to shed new light on the causal relationships bet...

  14. An End to Cattle Plague: Laboratory Capacity Building to Support the Global Rinderpest Eradication Programme

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency (IAEA) was established in 1957 as the world's 'Atoms for Peace' organization within the United Nations system. It currently has 151 Member States (March 2011) and works with partners worldwide to ensure the peaceful, safe and secure use of nuclear technologies. In 1964, IAEA and FAO established the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, to help countries apply nuclear science and related technologies for sustainable agricultural development. Through the concerted efforts of IAEA's Department of Technical Cooperation, the Joint FAO/IAEA Division and cooperation with FAO, IAEA helps Member States to develop sustainable capacities in nuclear science and related technologies, including by providing the training and analytical laboratory services necessary for the efficient and safe use of these technologies. Building on this experience, about 25 years ago, IAEA started to collaborate with FAO, OIE, OAU (now AU) and other regional organizations in Africa and Asia to support initernational efforts to diagnose, control and eradicate rinderpest. For centuries, rinderpest was one of the most dreaded livestock diseases. Its devastating effect on European cattle populations in the eighteenth century resulted in the first veterinary school, established in 1761 in France to educate veterinarians on the control of rinderpest and other animal diseases. Some 250 years later, the veterinary profession is set to declare the global eradication of rinderpest. During the nineteenth century, the application of quarantines helped keep rinderpest at bay, resulting in its eradication in Europe. In parallel with this, the development of vaccination strategies enabled containment of the disease in other regions, but it took until the early twentieth century to develop a standardized goat-adapted rinderpest vaccine. This vaccine was widely used for the control of rinderpest in Asia and Africa in the 1950s and 1960s, until it was replaced by the tissue culture-adapted vaccine, which was both more efficient and easier to produce.

  15. Development of Yersinia pestis F1 antigen-loaded microspheres vaccine against plague

    Directory of Open Access Journals (Sweden)

    Huang SS

    2014-02-01

    Full Text Available Shih-shiung Huang,1 I-Hsun Li,2,3 Po-da Hong,1 Ming-kung Yeh1,2,41Biomedical Engineering Program, Graduate Institute of Engineering, Department of Materials Science and Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan, Republic of China; 2School of Pharmacy, 3Department of Pharmacy Practice, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China; 4Food and Drug Administration, Ministry of Health and Welfare, Taipei, Taiwan, Republic of ChinaAbstract: Yersinia pestis F1 antigen-loaded poly(DL-lactide-co-glycolide/polyethylene glycol (PEG (PLGA/PEG microspheres were produced using a water-in-oil-in-water emulsion/solvent extraction technique and assayed for their percent yield, entrapment efficiency, surface morphology, particle size, zeta potential, in vitro release properties, and in vivo animal protect efficacy. The Y. pestis F1 antigen-loaded microspheres (mean particle size 3.8 µm exhibited a high loading capacity (4.5% w/w, yield (85.2%, and entrapment efficiency (38.1%, and presented a controlled in vitro release profile with a low initial burst (18.5%, then continued to release Y. pestis F1 antigen over 70 days. The distribution (% of Y. pestis F1 on the microspheres surface, outer layer, and core was 3.1%, 28.9%, and 60.7%, respectively. A steady release rate was noticed to be 0.55 µg Y. pestis F1 antigen/mg microspheres/day of Y. pestis F1 antigen release maintained for 42 days. The cumulative release amount at the 1st, 28th, and 42nd days was 8.2, 26.7, and 31.0 µg Y. pestis F1 antigen/mg microspheres, respectively. The 100 times median lethal dose 50% (LD50 of Y. pestis Yokohama-R strain by intraperitoneal injection challenge in mice test, in which mice received one dose of 40 µg F1 antigen content of PLGA/PEG microspheres, F1 antigen in Al(OH3, and in comparison with F1 antigen in Al(OH3 vaccine in two doses, was evaluated after given by subcutaneous immunization of BALB/c mice. The study results show that the greatest survival was observed in the group of mice immunized with one dose of F1 antigen-loaded PLGA/PEG microspheres, and two doses of F1 antigen in Al(OH3 vaccine (100%. In vivo vaccination studies also demonstrated that F1 vaccines microspheres had a protective ability; its steady-state IgG immune protection in mice plasma dramatic increased from 2 weeks (18,764±3,124 to 7 weeks (126,468±19,176 after vaccination. These findings strongly suggest that F1-antigen loaded microspheres vaccine offer a new therapeutic strategy in optimizing the vaccine incorporation and delivery properties of these potential vaccine targeting carriers.Keywords: PLGA, immunological, protective responses

  16. Advances in the mechanisms of atherosclerosis vulnerable plague and endoplasmic reticulum stress

    Institute of Scientific and Technical Information of China (English)

    Zhong Zhang; Ruo-Lan Huang; Ru Mo; Ling Wang; Xiao Chang; Mu-Juan Xu

    2016-01-01

    Objective:Ischemic stroke and coronary heart disease occupy the first two place of world health economic burden, atherosclerotic vulnerable plaque rupture as the common factor of these diseases, is thought to be a key target of ischemic cardiovascular and cerebrovascular disease control. Endoplasmic reticulum stress is one of the classical pathway of cell apoptosis. More and more studies have indicated that the endoplasmic reticulum stress pathway was involved in the development of atherosclerotic plaque rupture. In this paper, the three main signal pathways of endoplasmic reticulum stress, including Protein kinase RNA-like ER kinase (PERK), Activating transcription factor 6 (ATF6) and Inositol-requiring protein 1αα(IRE1α) were reviewed. The relationship between the risk factors of atherosclerosis (including hyperlipidemia, hypertension and hyperglycemia) and endoplasmic reticulum stress, and the relationship between major cellular components (macrophages, vascular endothelial cells, vascular smooth muscle cells and vascular smooth muscle cells) of vulnerable plaque and endoplasmic reticulum stress were reviewed.

  17. An outbreak of duck virus enteritis (duck plague) in a captive flock of mixed waterfowl

    Science.gov (United States)

    Montgomery, R.D.; Stein, G.; Novilla, M.N.; Hurley, Sarah S.; Fink, R.J.

    1981-01-01

    An outbreak of duck virus enteritis occurred in a flock of captive waterfowl composed of mallards (Anas platyrhynchos), black ducks (Anas rubripes), and Canada geese (Branta canadensis). Although all three species were housed together, morbidity and mortality were confined to the 227 black ducks and Canada geese, of which 180 died and the rest were left in a weakened condition. Lesions are given for 20 black ducks and 4 Canada geese dying from DVE. In addition, both horizontal and vertical transmission are discussed as possible sources of the virus that caused this outbreak.

  18. Global plagues and the Global Fund: Challenges in the fight against HIV, TB and malaria

    Directory of Open Access Journals (Sweden)

    Tan Darrell HS

    2003-04-01

    Full Text Available Abstract Background Although a grossly disproportionate burden of disease from HIV/AIDS, TB and malaria remains in the Global South, these infectious diseases have finally risen to the top of the international agenda in recent years. Ideal strategies for combating these diseases must balance the advantages and disadvantages of 'vertical' disease control programs and 'horizontal' capacity-building approaches. Discussion The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM represents an important step forward in the struggle against these pathogens. While its goals are laudable, significant barriers persist. Most significant is the pitiful lack of funds committed by world governments, particularly those of the very G8 countries whose discussions gave rise to the Fund. A drastic scaling up of resources is the first clear requirement for the GFATM to live up to the international community's lofty intentions. A directly related issue is that of maintaining a strong commitment to the treatment of the three diseases along with traditional prevention approaches, with the ensuing debates over providing affordable access to medications in the face of the pharmaceutical industry's vigorous protection of patent rights. Summary At this early point in the Fund's history, it remains to be seen how these issues will be resolved at the programming level. Nevertheless, it is clear that significant structural changes are required in such domains as global spending priorities, debt relief, trade policy, and corporate responsibility. HIV/AIDS, tuberculosis and malaria are global problems borne of gross socioeconomic inequality, and their solutions require correspondingly geopolitical solutions.

  19. Rein Tammik : Pidu katku ajal = Feast during the plague / Anneli Porri

    Index Scriptorium Estoniae

    Epner, Eero, 1978-

    2007-01-01

    Rein Tammiku fotorealistlik pildimaailm on iseseisev organism, mis ajuti genereerib ootamatuid tähenduslikke lühiühendusi. Erinevalt loodusmaalijatest, portreemaalijatest, meremaalijatest ja teistest maalib Rein Tammik pilte. Ta on pildimaalija. Tammikut huvitavad eelkõige visuaalsed paradoksid. Tammik asus juba 1970. aastail ajastuid ühte pilti kokku keevitama. Rembrandti grupiportreele «Kangrute gildi eesistujaist» ilmusid «Visarite» näod, Manet’ «Eine murul» leidis järsku aseme punaruudulisel linal jne. Historitsistlik eklektika - postmodernismi peamisi strateegiaid - on Tammiku loomingus täiesti selgelt loetav, teda on nimetatud esimeseks nõukogude postmodernistiks. Teatav nõukogude ajastu traumaatiline tajumine ilmneb tema töödes suuresti igatsusest kestvuse, jätkuvuse ja üldkehtivuse järele, mida 1970-1980-ndad aastad ei võimaldanud. 1992. aastast resideerub Prantsusmaal

  20. Dendrimer Phthalocyanine Theranostics for Flourescence Imaging and Photodynamic Therapy of Atheromatous Plagues

    DEFF Research Database (Denmark)

    Ficker, Mario

    carried out in vitro, and in vivo studies are in progress with highly promising initial data. The dendrimer phthalocyanine nanoparticle system was nally chosen by the Consortium of the FP-7 large-scale project CosmoPHOS-nano to be translated into a clinical phase I study in human patients and is currently...... in atherosclerosis, but they cannot remove or stabilize dangerous vulnerable plaques satisfyingly. This thesis describes the development of a theranostic dendrimer-based nanoparticle system for the detection (imaging) of vulnerable atheromatous plaques and their treatment/ stabilization by means of photodynamic...... therapy. For this purpose, a dendrimer nanoparticle system was developed that showed promising cytotoxicity and immunogenicity. These dendrimers were capable of solvating lipophilic phthalocyanines, which are second-generation photosensitizers. The dendrimer phthalocyanine conjugates had light emission...

  1. Abandonment of farmland and vegetation succession following the Eurasian plague pandemic of AD 1347-52

    NARCIS (Netherlands)

    D. Yeloff; B. van Geel

    2007-01-01

    Aim: This paper reviews the available documentary, archaeological and palaeoecological evidence for the abandonment of agricultural land and consequent regeneration of the forest in Europe after the Black Death. Location: Western and northern Europe. Methods: This review is the result of an exhausti

  2. Geochemical modeling

    International Nuclear Information System (INIS)

    Contributions to the workshop 'Geochemical modeling' from 19 to 20 September 1990 at the Karlsruhe Nuclear Research Centre. The report contains the programme and a selection of the lectures held at the workshop 'Geochemical modeling'. (BBR)

  3. Battery Modeling

    OpenAIRE

    Jongerden, M.R.; Haverkort, B.R.

    2008-01-01

    The use of mobile devices is often limited by the capacity of the employed batteries. The battery lifetime determines how long one can use a device. Battery modeling can help to predict, and possibly extend this lifetime. Many different battery models have been developed over the years. However, with these models one can only compute lifetimes for specific discharge profiles, and not for workloads in general. In this paper, we give an overview of the different battery models that are availabl...

  4. Computable models

    CERN Document Server

    Turner, Raymond

    2009-01-01

    Computational models can be found everywhere in present day science and engineering. In providing a logical framework and foundation for the specification and design of specification languages, Raymond Turner uses this framework to introduce and study computable models. In doing so he presents the first systematic attempt to provide computational models with a logical foundation. Computable models have wide-ranging applications from programming language semantics and specification languages, through to knowledge representation languages and formalism for natural language semantics. They are al

  5. Magnetosphere models

    International Nuclear Information System (INIS)

    In this work the most recent magnetospheric models are reviewed. After a short overview of the particle environment, a synthetic survey of the problem is given. For each feature of magnetospheric modelling (boundary, current sheet, ring-current) the approaches used by different authors are described. In the second part a description is given of the magnetospheric models, divided into four groups. In the last part, the different uses of magnetospheric models are illustrated by means of examples

  6. Model Building

    OpenAIRE

    Frampton, Paul H.

    1997-01-01

    In this talk I begin with some general discussion of model building in particle theory, emphasizing the need for motivation and testability. Three illustrative examples are then described. The first is the Left-Right model which provides an explanation for the chirality of quarks and leptons. The second is the 331-model which offers a first step to understanding the three generations of quarks and leptons. Third and last is the SU(15) model which can accommodate the light leptoquarks possibly...

  7. Constitutive Models

    DEFF Research Database (Denmark)

    Sales-Cruz, Mauricio; Piccolo, Chiara; Heitzig, Martina;

    2011-01-01

    This chapter presents various types of constitutive models and their applications. There are 3 aspects dealt with in this chapter, namely: creation and solution of property models, the application of parameter estimation and finally application examples of constitutive models. A systematic...

  8. Phoenix model

    Science.gov (United States)

    Phoenix (formerly referred to as the Second Generation Model or SGM) is a global general equilibrium model designed to analyze energy-economy-climate related questions and policy implications in the medium- to long-term. This model disaggregates the global economy into 26 industr...

  9. Interface models

    DEFF Research Database (Denmark)

    Ravn, Anders P.; Staunstrup, Jørgen

    1994-01-01

    This paper proposes a model for specifying interfaces between concurrently executing modules of a computing system. The model does not prescribe a particular type of communication protocol and is aimed at describing interfaces between both software and hardware modules or a combination of the two....... The model describes both functional and timing properties of an interface...

  10. Zeebrugge Model

    DEFF Research Database (Denmark)

    Sclütter, Flemming; Frigaard, Peter; Liu, Zhou

    This report presents the model test results on wave run-up on the Zeebrugge breakwater under the simulated prototype storms. The model test was performed in January 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University. The detailed description of the model is given...

  11. Hydrological models are mediating models

    Science.gov (United States)

    Babel, L. V.; Karssenberg, D.

    2013-08-01

    Despite the increasing role of models in hydrological research and decision-making processes, only few accounts of the nature and function of models exist in hydrology. Earlier considerations have traditionally been conducted while making a clear distinction between physically-based and conceptual models. A new philosophical account, primarily based on the fields of physics and economics, transcends classes of models and scientific disciplines by considering models as "mediators" between theory and observations. The core of this approach lies in identifying models as (1) being only partially dependent on theory and observations, (2) integrating non-deductive elements in their construction, and (3) carrying the role of instruments of scientific enquiry about both theory and the world. The applicability of this approach to hydrology is evaluated in the present article. Three widely used hydrological models, each showing a different degree of apparent physicality, are confronted to the main characteristics of the "mediating models" concept. We argue that irrespective of their kind, hydrological models depend on both theory and observations, rather than merely on one of these two domains. Their construction is additionally involving a large number of miscellaneous, external ingredients, such as past experiences, model objectives, knowledge and preferences of the modeller, as well as hardware and software resources. We show that hydrological models convey the role of instruments in scientific practice by mediating between theory and the world. It results from these considerations that the traditional distinction between physically-based and conceptual models is necessarily too simplistic and refers at best to the stage at which theory and observations are steering model construction. The large variety of ingredients involved in model construction would deserve closer attention, for being rarely explicitly presented in peer-reviewed literature. We believe that devoting

  12. Model Selection

    OpenAIRE

    Selén, Yngve

    2004-01-01

    Before using a parametric model one has to be sure that it offers a reasonable description of the system to be modeled. If a bad model structure is employed, the obtained model will also be bad, no matter how good is the parameter estimation method. There exist many possible ways of validating candidate models. This thesis focuses on one of the most common ways, i.e., the use of information criteria. First, some common information criteria are presented, and in the later chapters, various ext...

  13. Modeling Pharmacokinetics.

    Science.gov (United States)

    Bois, Frederic Y; Brochot, Céline

    2016-01-01

    Pharmacokinetics is the study of the fate of xenobiotics in a living organism. Physiologically based pharmacokinetic (PBPK) models provide realistic descriptions of xenobiotics' absorption, distribution, metabolism, and excretion processes. They model the body as a set of homogeneous compartments representing organs, and their parameters refer to anatomical, physiological, biochemical, and physicochemical entities. They offer a quantitative mechanistic framework to understand and simulate the time-course of the concentration of a substance in various organs and body fluids. These models are well suited for performing extrapolations inherent to toxicology and pharmacology (e.g., between species or doses) and for integrating data obtained from various sources (e.g., in vitro or in vivo experiments, structure-activity models). In this chapter, we describe the practical development and basic use of a PBPK model from model building to model simulations, through implementation with an easily accessible free software. PMID:27311461

  14. Mathematical modelling

    DEFF Research Database (Denmark)

    Blomhøj, Morten

    2004-01-01

    Developing competences for setting up, analysing and criticising mathematical models are normally seen as relevant only from and above upper secondary level. The general belief among teachers is that modelling activities presuppose conceptual understanding of the mathematics involved. Mathematical...... modelling, however, can be seen as a practice of teaching that place the relation between real life and mathematics into the centre of teaching and learning mathematics, and this is relevant at all levels. Modelling activities may motivate the learning process and help the learner to establish cognitive...... framework, which has been used for designing modelling courses, analysing students’ modelling activities, identifying learning obstacles in the modelling process and to guide the teachers interaction with the students during their work. This will be illustrated with an example from a developmental project...

  15. Cadastral Modeling

    DEFF Research Database (Denmark)

    Stubkjær, Erik

    2005-01-01

    to the modeling of an industrial sector, as it aims at rendering the basic concepts that relate to the domain of real estate and the pertinent human activities. The palpable objects are pieces of land and buildings, documents, data stores and archives, as well as persons in their diverse roles as owners, holders...... to land. The paper advances the position that cadastral modeling has to include not only the physical objects, agents, and information sets of the domain, but also the objectives or requirements of cadastral systems.......Modeling is a term that refers to a variety of efforts, including data and process modeling. The domain to be modeled may be a department, an organization, or even an industrial sector. E-business presupposes the modeling of an industrial sector, a substantial task. Cadastral modeling compares...

  16. ICRF modelling

    International Nuclear Information System (INIS)

    This lecture provides a survey of the methods used to model fast magnetosonic wave coupling, propagation, and absorption in tokamaks. The validity and limitations of three distinct types of modelling codes, which will be contrasted, include discrete models which utilize ray tracing techniques, approximate continuous field models based on a parabolic approximation of the wave equation, and full field models derived using finite difference techniques. Inclusion of mode conversion effects in these models and modification of the minority distribution function will also be discussed. The lecture will conclude with a presentation of time-dependent global transport simulations of ICRF-heated tokamak discharges obtained in conjunction with the ICRF modelling codes. 52 refs., 15 figs

  17. Model choice versus model criticism

    OpenAIRE

    Robert, Christian P.; Mengersen, Kerrie; Chen, Carla

    2009-01-01

    The new perspectives on ABC and Bayesian model criticisms presented in Ratmann et al.(2009) are challenging standard approaches to Bayesian model choice. We discuss here some issues arising from the authors' approach, including prior influence, model assessment and criticism, and the meaning of error in ABC.

  18. Would You Like Fries with That? The Dangers of the Customer Service Model of Reading Teacher Education

    Science.gov (United States)

    Ness, Molly K.; Osborn, Terry A.

    2010-01-01

    Reading teacher education, as is true with much of higher education, is plagued with pressures of providing "here and now" answers to very complex, entangled issues. The reading methods course becomes the site of many of these pressures, despite considerable insights provided by scholars such as Kumaravadivelu (2001) that "methods" may be more of…

  19. Mathematical modelling

    CERN Document Server

    2016-01-01

    This book provides a thorough introduction to the challenge of applying mathematics in real-world scenarios. Modelling tasks rarely involve well-defined categories, and they often require multidisciplinary input from mathematics, physics, computer sciences, or engineering. In keeping with this spirit of modelling, the book includes a wealth of cross-references between the chapters and frequently points to the real-world context. The book combines classical approaches to modelling with novel areas such as soft computing methods, inverse problems, and model uncertainty. Attention is also paid to the interaction between models, data and the use of mathematical software. The reader will find a broad selection of theoretical tools for practicing industrial mathematics, including the analysis of continuum models, probabilistic and discrete phenomena, and asymptotic and sensitivity analysis.

  20. Turbulence modelling

    International Nuclear Information System (INIS)

    This paper is an introduction course in modelling turbulent thermohydraulics, aimed at computational fluid dynamics users. No specific knowledge other than the Navier Stokes equations is required beforehand. Chapter I (which those who are not beginners can skip) provides basic ideas on turbulence physics and is taken up in a textbook prepared by the teaching team of the ENPC (Benque, Viollet). Chapter II describes turbulent viscosity type modelling and the 2k-ε two equations model. It provides details of the channel flow case and the boundary conditions. Chapter III describes the 'standard' (Rij-ε) Reynolds tensions transport model and introduces more recent models called 'feasible'. A second paper deals with heat transfer and the effects of gravity, and returns to the Reynolds stress transport model. (author)

  1. Logistic models

    OpenAIRE

    Sochůrková, Adéla

    2012-01-01

    The aim of this thesis is the compilation of an inventory management methods, describe their principles and assess the appropriateness of their use. In the introductory part of the work, "The nature and importance of inventory management" are briefly described the inventory management, the main objectives of inventory control models, the basic division of inventory species and costs of supply. The following chapter "Overview of inventory control models" includes a breakdown of models from dif...

  2. STEREOMETRIC MODELLING

    OpenAIRE

    Grimaldi, P.

    2012-01-01

    These mandatory guidelines are provided for preparation of papers accepted for publication in the series of Volumes of The The stereometric modelling means modelling achieved with : – the use of a pair of virtual cameras, with parallel axes and positioned at a mutual distance average of 1/10 of the distance camera-object (in practice the realization and use of a stereometric camera in the modeling program); – the shot visualization in two distinct windows &nda...

  3. Spherical models

    CERN Document Server

    Wenninger, Magnus J

    2012-01-01

    Well-illustrated, practical approach to creating star-faced spherical forms that can serve as basic structures for geodesic domes. Complete instructions for making models from circular bands of paper with just a ruler and compass. Discusses tessellation, or tiling, and how to make spherical models of the semiregular solids and concludes with a discussion of the relationship of polyhedra to geodesic domes and directions for building models of domes. "". . . very pleasant reading."" - Science. 1979 edition.

  4. Why Model?

    OpenAIRE

    Epstein, Joshua M.

    2008-01-01

    This address treats some enduring misconceptions about modeling. One of these is that the goal is always prediction. The lecture distinguishes between explanation and prediction as modeling goals, and offers sixteen reasons other than prediction to build a model. It also challenges the common assumption that scientific theories arise from and 'summarize' data, when often, theories precede and guide data collection; without theory, in other words, it is not clear what data to collect. Among ot...

  5. Zeebrugge Model

    DEFF Research Database (Denmark)

    Liu, Zhou; Frigaard, Peter

    This report presents the model on wave run-up and run-down on the Zeebrugge breakwater under short-crested oblique wave attacks. The model test was performed in March-April 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University.......This report presents the model on wave run-up and run-down on the Zeebrugge breakwater under short-crested oblique wave attacks. The model test was performed in March-April 2000 at the Hydraulics & Coastal Engineering Laboratory, Aalborg University....

  6. Ventilation Model

    International Nuclear Information System (INIS)

    The purpose of the Ventilation Model is to simulate the heat transfer processes in and around waste emplacement drifts during periods of forced ventilation. The model evaluates the effects of emplacement drift ventilation on the thermal conditions in the emplacement drifts and surrounding rock mass, and calculates the heat removal by ventilation as a measure of the viability of ventilation to delay the onset of peak repository temperature and reduce its magnitude. The heat removal by ventilation is temporally and spatially dependent, and is expressed as the fraction of heat carried away by the ventilation air compared to the fraction of heat produced by radionuclide decay. One minus the heat removal is called the wall heat fraction, or the remaining amount of heat that is transferred via conduction to the surrounding rock mass. Downstream models, such as the ''Multiscale Thermohydrologic Model'' (BSC 2001), use the wall heat fractions as outputted from the Ventilation Model to initialize their post-closure analyses. The Ventilation Model report was initially developed to analyze the effects of preclosure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts, and to provide heat removal data to support EBS design. Revision 00 of the Ventilation Model included documentation of the modeling results from the ANSYS-based heat transfer model. The purposes of Revision 01 of the Ventilation Model are: (1) To validate the conceptual model for preclosure ventilation of emplacement drifts and verify its numerical application in accordance with new procedural requirements as outlined in AP-SIII-10Q, Models (Section 7.0). (2) To satisfy technical issues posed in KTI agreement RDTME 3.14 (Reamer and Williams 2001a). Specifically to demonstrate, with respect to the ANSYS ventilation model, the adequacy of the discretization (Section 6.2.3.1), and the downstream applicability of the model results (i.e. wall heat fractions) to initialize post

  7. Ventilation Model

    Energy Technology Data Exchange (ETDEWEB)

    V. Chipman

    2002-10-05

    The purpose of the Ventilation Model is to simulate the heat transfer processes in and around waste emplacement drifts during periods of forced ventilation. The model evaluates the effects of emplacement drift ventilation on the thermal conditions in the emplacement drifts and surrounding rock mass, and calculates the heat removal by ventilation as a measure of the viability of ventilation to delay the onset of peak repository temperature and reduce its magnitude. The heat removal by ventilation is temporally and spatially dependent, and is expressed as the fraction of heat carried away by the ventilation air compared to the fraction of heat produced by radionuclide decay. One minus the heat removal is called the wall heat fraction, or the remaining amount of heat that is transferred via conduction to the surrounding rock mass. Downstream models, such as the ''Multiscale Thermohydrologic Model'' (BSC 2001), use the wall heat fractions as outputted from the Ventilation Model to initialize their post-closure analyses. The Ventilation Model report was initially developed to analyze the effects of preclosure continuous ventilation in the Engineered Barrier System (EBS) emplacement drifts, and to provide heat removal data to support EBS design. Revision 00 of the Ventilation Model included documentation of the modeling results from the ANSYS-based heat transfer model. The purposes of Revision 01 of the Ventilation Model are: (1) To validate the conceptual model for preclosure ventilation of emplacement drifts and verify its numerical application in accordance with new procedural requirements as outlined in AP-SIII-10Q, Models (Section 7.0). (2) To satisfy technical issues posed in KTI agreement RDTME 3.14 (Reamer and Williams 2001a). Specifically to demonstrate, with respect to the ANSYS ventilation model, the adequacy of the discretization (Section 6.2.3.1), and the downstream applicability of the model results (i.e. wall heat fractions) to

  8. Modeling Documents with Event Model

    Directory of Open Access Journals (Sweden)

    Longhui Wang

    2015-08-01

    Full Text Available Currently deep learning has made great breakthroughs in visual and speech processing, mainly because it draws lessons from the hierarchical mode that brain deals with images and speech. In the field of NLP, a topic model is one of the important ways for modeling documents. Topic models are built on a generative model that clearly does not match the way humans write. In this paper, we propose Event Model, which is unsupervised and based on the language processing mechanism of neurolinguistics, to model documents. In Event Model, documents are descriptions of concrete or abstract events seen, heard, or sensed by people and words are objects in the events. Event Model has two stages: word learning and dimensionality reduction. Word learning is to learn semantics of words based on deep learning. Dimensionality reduction is the process that representing a document as a low dimensional vector by a linear mode that is completely different from topic models. Event Model achieves state-of-the-art results on document retrieval tasks.

  9. Education models

    OpenAIRE

    Poortman, Sybilla; Sloep, Peter

    2006-01-01

    Educational models describes a case study on a complex learning object. Possibilities are investigated for using this learning object, which is based on a particular educational model, outside of its original context. Furthermore, this study provides advice that might lead to an increase in teachers’ motivation for using and sharing learning objects. This document is aimed at teachers and educational designers.

  10. Neurofuzzy Modelling

    DEFF Research Database (Denmark)

    Jantzen, Jan

    1998-01-01

    A neural network can approximate a function, but it is impossible to interpret the result in terms of natural language. The fusion of neural networks and fuzzy logic in neurofuzzy models provide learning as well as readability. Control engineers find this useful, because the models can...

  11. Modeling Sunspots

    Science.gov (United States)

    Oh, Phil Seok; Oh, Sung Jin

    2013-01-01

    Modeling in science has been studied by education researchers for decades and is now being applied broadly in school. It is among the scientific practices featured in the "Next Generation Science Standards" ("NGSS") (Achieve Inc. 2013). This article describes modeling activities in an extracurricular science club in a high…

  12. Didactical modelling

    DEFF Research Database (Denmark)

    Højgaard, Tomas; Hansen, Rune

    2016-01-01

    The purpose of this paper is to introduce Didactical Modelling as a research methodology in mathematics education. We compare the methodology with other approaches and argue that Didactical Modelling has its own specificity. We discuss the methodological “why” and explain why we find it useful...

  13. Animal models

    DEFF Research Database (Denmark)

    Gøtze, Jens Peter; Krentz, Andrew

    2014-01-01

    In this issue of Cardiovascular Endocrinology, we are proud to present a broad and dedicated spectrum of reviews on animal models in cardiovascular disease. The reviews cover most aspects of animal models in science from basic differences and similarities between small animals and the human...

  14. Martingale Model

    OpenAIRE

    Giandomenico, Rossano

    2006-01-01

    The model determines a stochastic continuous process as continuous limit of a stochastic discrete process so to show that the stochastic continuous process converges to the stochastic discrete process such that we can integrate it. Furthermore, the model determines the expected volatility and the expected mean so to show that the volatility and the mean are increasing function of the time.

  15. Scribe modeller

    DEFF Research Database (Denmark)

    Løssing, Ulrik

    1986-01-01

    Ulrik Løssing har redigeret, illustreret og oversat: "Scribe Modeller System, Sheffield, november 1985" af forfatterne: Cedric Green, David Cooper og John Wells.......Ulrik Løssing har redigeret, illustreret og oversat: "Scribe Modeller System, Sheffield, november 1985" af forfatterne: Cedric Green, David Cooper og John Wells....

  16. Linguistic models and linguistic modeling.

    Science.gov (United States)

    Pedryez, W; Vasilakos, A V

    1999-01-01

    The study is concerned with a linguistic approach to the design of a new category of fuzzy (granular) models. In contrast to numerically driven identification techniques, we concentrate on budding meaningful linguistic labels (granules) in the space of experimental data and forming the ensuing model as a web of associations between such granules. As such models are designed at the level of information granules and generate results in the same granular rather than pure numeric format, we refer to them as linguistic models. Furthermore, as there are no detailed numeric estimation procedures involved in the construction of the linguistic models carried out in this way, their design mode can be viewed as that of a rapid prototyping. The underlying algorithm used in the development of the models utilizes an augmented version of the clustering technique (context-based clustering) that is centered around a notion of linguistic contexts-a collection of fuzzy sets or fuzzy relations defined in the data space (more precisely a space of input variables). The detailed design algorithm is provided and contrasted with the standard modeling approaches commonly encountered in the literature. The usefulness of the linguistic mode of system modeling is discussed and illustrated with the aid of numeric studies including both synthetic data as well as some time series dealing with modeling traffic intensity over a broadband telecommunication network.

  17. OSPREY Model

    Energy Technology Data Exchange (ETDEWEB)

    Veronica J. Rutledge

    2013-01-01

    The absence of industrial scale nuclear fuel reprocessing in the U.S. has precluded the necessary driver for developing the advanced simulation capability now prevalent in so many other countries. Thus, it is essential to model complex series of unit operations to simulate, understand, and predict inherent transient behavior and feedback loops. A capability of accurately simulating the dynamic behavior of advanced fuel cycle separation processes will provide substantial cost savings and many technical benefits. The specific fuel cycle separation process discussed in this report is the off-gas treatment system. The off-gas separation consists of a series of scrubbers and adsorption beds to capture constituents of interest. Dynamic models are being developed to simulate each unit operation involved so each unit operation can be used as a stand-alone model and in series with multiple others. Currently, an adsorption model has been developed within Multi-physics Object Oriented Simulation Environment (MOOSE) developed at the Idaho National Laboratory (INL). Off-gas Separation and REcoverY (OSPREY) models the adsorption of off-gas constituents for dispersed plug flow in a packed bed under non-isothermal and non-isobaric conditions. Inputs to the model include gas, sorbent, and column properties, equilibrium and kinetic data, and inlet conditions. The simulation outputs component concentrations along the column length as a function of time from which breakthrough data is obtained. The breakthrough data can be used to determine bed capacity, which in turn can be used to size columns. It also outputs temperature along the column length as a function of time and pressure drop along the column length. Experimental data and parameters were input into the adsorption model to develop models specific for krypton adsorption. The same can be done for iodine, xenon, and tritium. The model will be validated with experimental breakthrough curves. Customers will be given access to

  18. Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

    International Nuclear Information System (INIS)

    Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis (YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability (Rwork = 16.2, Rfree = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh

  19. Metabolism and evolution: A comparative study of reconstructed genome-level metabolic networks

    Science.gov (United States)

    Almaas, Eivind

    2008-03-01

    The availability of high-quality annotations of sequenced genomes has made it possible to generate organism-specific comprehensive maps of cellular metabolism. Currently, more than twenty such metabolic reconstructions are publicly available, with the majority focused on bacteria. A typical metabolic reconstruction for a bacterium results in a complex network containing hundreds of metabolites (nodes) and reactions (links), while some even contain more than a thousand. The constrain-based optimization approach of flux-balance analysis (FBA) is used to investigate the functional characteristics of such large-scale metabolic networks, making it possible to estimate an organism's growth behavior in a wide variety of nutrient environments, as well as its robustness to gene loss. We have recently completed the genome-level metabolic reconstruction of Yersinia pseudotuberculosis, as well as the three Yersinia pestis biovars Antiqua, Mediaevalis, and Orientalis. While Y. pseudotuberculosis typically only causes fever and abdominal pain that can mimic appendicitis, the evolutionary closely related Y. pestis strains are the aetiological agents of the bubonic plague. In this presentation, I will discuss our results and conclusions from a comparative study on the evolution of metabolic function in the four Yersiniae networks using FBA and related techniques, and I will give particular focus to the interplay between metabolic network topology and evolutionary flexibility.

  20. Complete Genome Sequence of Yersinia pestis Strains Antiqua andNepal516: Evidence of Gene Reduction in an Emerging Pathogen

    Energy Technology Data Exchange (ETDEWEB)

    Chain, Patrick S.G.; Hu, Ping; Malfatti, Stephanie A.; Radnedge,Lyndsay; Larimer, Frank; Vergez, Lisa M.; Worsham, Patricia; Chu, May C.; Andersen, Gary L.

    2006-01-16

    Yersinia pestis, the causative agent of bubonic andpneumonicplague, has undergone detailed study at the molecular level. Tofurther investigate the genomic diversity among this group and to helpcharacterize lineages of the plague organism that have no sequencedmembers, we present here the genomes of two isolates of the "classical"Antiqua biovar, strains Antiqua and Nepal516. The genomes of Antiqua andNepal516 are 4.7 Mb and 4.5 Mb and encode 4,138 and 3,956 open readingframes respectively. Though both strains belong to one of the threeclassical biovars, they represent separate lineages defined by recentphylogenetic studies. We compare all five currently sequenced Y. pestisgenomes and the corresponding features in Y. pseudotuberculosis. Thereare strain-specific rearrangements, insertions, deletions, singlenucleotide polymorphisms and a unique distribution of insertionsequences. We found 453 single nucleotide polymorphisms in protein codingregions, which were used to assess evolutionary relationships of these Y.pestis strains. Gene reduction analysis revealed that the gene deletionprocesses are under selective pressure and many of the inactivations areprobably related to the organism s interaction with its host environment.The results presented here clearly demonstrate the differences betweenthe two Antiqua lineages and support the notion that grouping Y. pestisstrains based strictly on the classical definition of biovars (predicatedupon two biochemical assays) does not accurately reflect the phylogeneticrelationships within this species. Comparison of four virulent Y. pestisstrains with the human-avirulent strain 91001 provides further insightinto the genetic basis of virulence to humans.

  1. The case for selection at CCR5-Delta32.

    Directory of Open Access Journals (Sweden)

    Pardis C Sabeti

    2005-11-01

    Full Text Available The C-C chemokine receptor 5, 32 base-pair deletion (CCR5-Delta32 allele confers strong resistance to infection by the AIDS virus HIV. Previous studies have suggested that CCR5-Delta32 arose within the past 1,000 y and rose to its present high frequency (5%-14% in Europe as a result of strong positive selection, perhaps by such selective agents as the bubonic plague or smallpox during the Middle Ages. This hypothesis was based on several lines of evidence, including the absence of the allele outside of Europe and long-range linkage disequilibrium at the locus. We reevaluated this evidence with the benefit of much denser genetic maps and extensive control data. We find that the pattern of genetic variation at CCR5-Delta32 does not stand out as exceptional relative to other loci across the genome. Moreover using newer genetic maps, we estimated that the CCR5-Delta32 allele is likely to have arisen more than 5,000 y ago. While such results can not rule out the possibility that some selection may have occurred at C-C chemokine receptor 5 (CCR5, they imply that the pattern of genetic variation seen at CCR5-Delta32 is consistent with neutral evolution. More broadly, the results have general implications for the design of future studies to detect the signs of positive selection in the human genome.

  2. Fleas and flea control

    Directory of Open Access Journals (Sweden)

    Dautović Živomir

    2002-01-01

    Full Text Available Fleas as hemeatophagous arthropodes take part in the spreading of certain diseases such as bubonic plague, murine typhus, tick-borne typhus tularaemia, or can be transitory hosts for certain species of cestodes for dogs and cats. Depending on the type of host on which fleas persist and the habitat, measures that can be taken to control them can be only sanitary-hygiene, individual, or treatment of the habitat. Sanitary-hygiene measures mostly consist of regular cleaning. Individual protection implies the use of insecticides for re-impregnating clothing, spraying clothing and the use of repellents. Treatment of habitats comprises the use of insecticides of the group of organophosphates, metyl-carbamates, pyrethroids and organo-chlorine compounds, instruments for dusting and spraying. In addition to these compounds, preparations based on imidaclopride, fipronyl and inhibitors of insect growth (IGRs and development (IDIs are also used. Flea control in household pets is implemented using measures of individual protection and treatment of their habitats.

  3. Nuclear Magnetic Resonance Characterization of the Type III Secretion System Tip Chaperone Protein PcrG of Pseudomonas aeruginosa.

    Science.gov (United States)

    Chaudhury, Sukanya; Nordhues, Bryce A; Kaur, Kawaljit; Zhang, Na; De Guzman, Roberto N

    2015-11-01

    Lung infection with Pseudomonas aeruginosa is the leading cause of death among cystic fibrosis patients. To initiate infection, P. aeruginosa assembles a protein nanomachine, the type III secretion system (T3SS), to inject bacterial proteins directly into target host cells. An important regulator of the P. aeruginosa T3SS is the chaperone protein PcrG, which forms a complex with the tip protein, PcrV. In addition to its role as a chaperone to the tip protein, PcrG also regulates protein secretion. PcrG homologues are also important in the T3SS of other pathogens such as Yersinia pestis, the causative agent of bubonic plague. The atomic structure of PcrG or any member of the family of tip protein chaperones is currently unknown. Here, we show by circular dichroism and nuclear magnetic resonance (NMR) spectroscopy that PcrG lacks a tertiary structure. However, it is not completely disordered but contains secondary structures dominated by two long α-helices from residue 16 to 41 and from residue 55 to 76. The helices of PcrG are partially formed, have similar backbone dynamics, and are flexible. NMR titrations show that the entire length of PcrG residues from position 9 to 76 is involved in binding to PcrV. PcrG adds to the growing list of partially folded or unstructured proteins with important roles in type III secretion.

  4. Palaeopathology and genes: investigating the genetics of infectious diseases in excavated human skeletal remains and mummies from past populations.

    Science.gov (United States)

    Anastasiou, Evilena; Mitchell, Piers D

    2013-10-01

    The aim of this paper is to review the use of genetics in palaeomicrobiology, and to highlight the importance of understanding past diseases. Palaeomicrobiology is the study of disease pathogens in skeletal and mummified remains from archaeological contexts. It has revolutionarised our understanding of health in the past by enabling a deeper knowledge of the origins and evolution of many diseases that have shaped us as a species. Bacterial diseases explored include tuberculosis, leprosy, bubonic plague, typhoid, syphilis, endemic and epidemic typhus, trench fever, and Helicobacter pylori. Viral diseases discussed include influenza, hepatitis B, human papilloma virus (HPV), human T-cell lymphotrophic virus (HTLV-1) and human immunodeficiency virus (HIV). Parasitic diseases investigated include malaria, leishmaniasis, Chagas' disease, roundworm, whipworm, pinworm, Chinese liver fluke, fleas and lice. Through a better understanding of disease origins and their evolution, we can place into context how many infectious diseases are changing over time, and so help us estimate how they may change in the future. PMID:23792062

  5. Structure of a complex of uridine phosphorylase from Yersinia pseudotuberculosis with the modified bacteriostatic antibacterial drug determined by X-ray crystallography and computer analysis

    Energy Technology Data Exchange (ETDEWEB)

    Balaev, V. V.; Lashkov, A. A., E-mail: alashkov83@gmail.com; Gabdoulkhakov, A. G.; Seregina, T. A.; Dontsova, M. V.; Mikhailov, A. M. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2015-03-15

    Pseudotuberculosis and bubonic plague are acute infectious diseases caused by the bacteria Yersinia pseudotuberculosis and Yersinia pestis. These diseases are treated, in particular, with trimethoprim and its modified analogues. However, uridine phosphorylases (pyrimidine nucleoside phosphorylases) that are present in bacterial cells neutralize the action of trimethoprim and its modified analogues on the cells. In order to reveal the character of the interaction of the drug with bacterial uridine phosphorylase, the atomic structure of the unligated molecule of uridine-specific pyrimidine nucleoside phosphorylase from Yersinia pseudotuberculosis (YptUPh) was determined by X-ray diffraction at 1.7 Å resolution with high reliability (R{sub work} = 16.2, R{sub free} = 19.4%; r.m.s.d. of bond lengths and bond angles are 0.006 Å and 1.005°, respectively; DPI = 0.107 Å). The atoms of the amino acid residues of the functionally important secondary-structure elements—the loop L9 and the helix H8—of the enzyme YptUPh were located. The three-dimensional structure of the complex of YptUPh with modified trimethoprim—referred to as 53I—was determined by the computer simulation. It was shown that 53I is a pseudosubstrate of uridine phosphorylases, and its pyrimidine-2,4-diamine group is located in the phosphate-binding site of the enzyme YptUPh.

  6. [Goethe's philosophical-medical masks, in Faust].

    Science.gov (United States)

    de Castro-Peredo, Hugo Fernandez

    2006-01-01

    At the beginning of the XXI century the health profession is engaged in a medical ethical and moral crisis and society, hurt by the pandemic of violence and impunity, feels the effect of a state of legal crisis unable to find a viable scientific or humanistic answer. This manuscript, is the result of an investigation into the Johann Wolfgang Goethe's tragedy of the nineteenth century, Faust. It demonstrates the coincidence of real life subjects and objects with literary subjects and objects represented, by means of the interpretation of the paradigms, problems, dilemmas and identified cases of medical ethical-morals: dáimon, reflection-solitude, free will, good-evil, Eros, learned ignorance, genes, epistemology, medical etiquette, paternalism, anatomy of the personality, Hyppocratism, will, good sense of humor, bubonic plague. Faust can be construed as a new path for change--towards the common good--of the physician if traced by their will and recovering the represented real objects, decides to meditate free and lonely on its professional exercise, medical knowledge and the doctor-patient relationship. PMID:17201118

  7. Infectious diseases -- new and ancient threats to world health.

    Science.gov (United States)

    Olshansky, S J; Carnes, B; Rogers, R G; Smith, L

    1997-07-01

    Infectious and parasitic diseases remain a leading cause of death and disability in developing countries and are re-emerging as a serious health problem in developed countries. Outbreaks of Ebola, dengue hemorrhagic fever, cholera, and bubonic plague have occurred in low-income countries and multidrug-resistant organisms have surfaced throughout the world. Since 1973, over 28 new disease-causing microbes have been identified. This issue of "Population Bulletin" analyzes the impact of factors such as population growth, urbanization, migration, poverty, travel, agricultural practices, climate changes, natural disasters, and medical technology on the resurgence of infectious and parasitic diseases as well as the influence of diseases such as AIDS on population dynamics and socioeconomic development. Most of these diseases could be prevented, cured, or eradicated with known public health measures. National governments can help reduce poverty, step up immunization programs, and lessen the chances of introducing new diseases. Nongovernmental organizations can disseminate preventive knowledge and monitor disease outbreaks. The medical profession can strengthen infection control precautions and institute surveillance of the use of antibiotics and other antimicrobial agents. Since the geographic isolation that used to contain disease outbreaks has been replaced by permeable international borders, the campaign against infectious and parasitic diseases must be global. PMID:12292663

  8. Stereometric Modelling

    Science.gov (United States)

    Grimaldi, P.

    2012-07-01

    These mandatory guidelines are provided for preparation of papers accepted for publication in the series of Volumes of The The stereometric modelling means modelling achieved with : - the use of a pair of virtual cameras, with parallel axes and positioned at a mutual distance average of 1/10 of the distance camera-object (in practice the realization and use of a stereometric camera in the modeling program); - the shot visualization in two distinct windows - the stereoscopic viewing of the shot while modelling. Since the definition of "3D vision" is inaccurately referred to as the simple perspective of an object, it is required to add the word stereo so that "3D stereo vision " shall stand for "three-dimensional view" and ,therefore, measure the width, height and depth of the surveyed image. Thanks to the development of a stereo metric model , either real or virtual, through the "materialization", either real or virtual, of the optical-stereo metric model made visible with a stereoscope. It is feasible a continuous on line updating of the cultural heritage with the help of photogrammetry and stereometric modelling. The catalogue of the Architectonic Photogrammetry Laboratory of Politecnico di Bari is available on line at: http://rappresentazione.stereofot.it:591/StereoFot/FMPro?-db=StereoFot.fp5&-lay=Scheda&-format=cerca.htm&-view

  9. Model theory

    CERN Document Server

    Hodges, Wilfrid

    1993-01-01

    An up-to-date and integrated introduction to model theory, designed to be used for graduate courses (for students who are familiar with first-order logic), and as a reference for more experienced logicians and mathematicians.

  10. Paleoclimate Modeling

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Computer simulations of past climate. Variables provided as model output are described by parameter keyword. In some cases the parameter keywords are a subset of...

  11. Modeling Arcs

    CERN Document Server

    Insepov, Zeke; Veitzer, Seth; Mahalingam, Sudhakar

    2011-01-01

    Although vacuum arcs were first identified over 110 years ago, they are not yet well understood. We have since developed a model of breakdown and gradient limits that tries to explain, in a self-consistent way: arc triggering, plasma initiation, plasma evolution, surface damage and gra- dient limits. We use simple PIC codes for modeling plasmas, molecular dynamics for modeling surface breakdown, and surface damage, and mesoscale surface thermodynamics and finite element electrostatic codes for to evaluate surface properties. Since any given experiment seems to have more variables than data points, we have tried to consider a wide variety of arcing (rf structures, e beam welding, laser ablation, etc.) to help constrain the problem, and concentrate on common mechanisms. While the mechanisms can be comparatively simple, modeling can be challenging.

  12. Accelerated life models modeling and statistical analysis

    CERN Document Server

    Bagdonavicius, Vilijandas

    2001-01-01

    Failure Time DistributionsIntroductionParametric Classes of Failure Time DistributionsAccelerated Life ModelsIntroductionGeneralized Sedyakin's ModelAccelerated Failure Time ModelProportional Hazards ModelGeneralized Proportional Hazards ModelsGeneralized Additive and Additive-Multiplicative Hazards ModelsChanging Shape and Scale ModelsGeneralizationsModels Including Switch-Up and Cycling EffectsHeredity HypothesisSummaryAccelerated Degradation ModelsIntroductionDegradation ModelsModeling the Influence of Explanatory Varia

  13. Modelling Constructs

    DEFF Research Database (Denmark)

    Kindler, Ekkart

    2009-01-01

    There are many different notations and formalisms for modelling business processes and workflows. These notations and formalisms have been introduced with different purposes and objectives. Later, influenced by other notations, comparisons with other tools, or by standardization efforts, these no......There are many different notations and formalisms for modelling business processes and workflows. These notations and formalisms have been introduced with different purposes and objectives. Later, influenced by other notations, comparisons with other tools, or by standardization efforts......, these notations have been extended in order to increase expressiveness and to be more competitive. This resulted in an increasing number of notations and formalisms for modelling business processes and in an increase of the different modelling constructs provided by modelling notations, which makes it difficult...... to compare modelling notations and to make transformations between them. One of the reasons is that, in each notation, the new concepts are introduced in a different way by extending the already existing constructs. In this chapter, we go the opposite direction: We show that it is possible to add most...

  14. Model fit and model selection

    OpenAIRE

    Kocherlakota, Narayana R.

    2007-01-01

    This paper uses an example to show that a model that fits the available data perfectly may provide worse answers to policy questions than an alternative, imperfectly fitting model. The author argues that, in the context of Bayesian estimation, this result can be interpreted as being due to the use of an inappropriate prior over the parameters of shock processes. He urges the use of priors that are obtained from explicit auxiliary information, not from the desire to obtain identification.

  15. Model composition in model checking

    OpenAIRE

    Felscher, Ingo

    2014-01-01

    Model-checking allows one to formally check properties of systems: these properties are modeled as logic formulas and the systems as structures like transition systems. These transition systems are often composed, i.e., they arise in form of products or sums. The composition technique allows us to deduce the truth of a formula in the composed system from "interface information": the truth of formulas for the component systems and information in which components which of these formulas hold. W...

  16. Modelling Defiguration

    DEFF Research Database (Denmark)

    Bork Petersen, Franziska

    2013-01-01

    focus centres on how the catwalk scenography evokes a ‘defiguration’ of the walking models and to what effect. Vibskov’s mobile catwalk draws attention to the walk, which is a key element of models’ performance but which usually functions in fashion shows merely to present clothes in the most...... advantageous manner. Stepping on the catwalk’s sloping, moving surfaces decelerates the models’ walk and makes it cautious, hesitant and shaky: suddenly the models lack exactly the affirmative, staccato, striving quality of motion, and the condescending expression that they perform on most contemporary...... determines the models’ walk. Furthermore, letting the models set off sound through triggers with attached sound samples gives them an implied agency. This calls into question the designer’s unrestricted authorship....

  17. Persistent Modelling

    DEFF Research Database (Denmark)

    2012-01-01

    The relationship between representation and the represented is examined here through the notion of persistent modelling. This notion is not novel to the activity of architectural design if it is considered as describing a continued active and iterative engagement with design concerns – an evident...... characteristic of architectural practice. But the persistence in persistent modelling can also be understood to apply in other ways, reflecting and anticipating extended roles for representation. This book identifies three principle areas in which these extensions are becoming apparent within contemporary....... It also provides critical insight into the use of contemporary modelling tools and methods, together with an examination of the implications their use has within the territories of architectural design, realisation and experience....

  18. Inflatable Models

    Institute of Scientific and Technical Information of China (English)

    Ling Li; Vasily Volkov

    2006-01-01

    A physically-based model is presented for the simulation of a new type of deformable objects-inflatable objects, such as shaped balloons, which consist of pressurized air enclosed by an elastic surface. These objects have properties inherent in both 3D and 2D elastic bodies, as they demonstrate the behaviour of 3D shapes using 2D formulations. As there is no internal structure in them, their behaviour is substantially different from the behaviour of deformable solid objects. We use one of the few available models for deformable surfaces, and enhance it to include the forces of internal and external pressure. These pressure forces may also incorporate buoyancy forces, to allow objects filled with a low density gas to float in denser media. The obtained models demonstrate rich dynamic behaviour, such as bouncing, floating, deflation and inflation.

  19. Supernova models

    International Nuclear Information System (INIS)

    Recent progress in understanding the observed properties of Type I supernovae as a consequence of the thermonuclear detonation of white dwarf stars and the ensuing decay of the 56Ni produced therein is reviewed. Within the context of this model for Type I explosions and the 1978 model for Type II explosions, the expected nucleosynthesis and gamma-line spectra from both kinds of supernovae are presented. Finally, a qualitatively new approach to the problem of massive star death and Type II supernovae based upon a combination of rotation and thermonuclear burning is discussed

  20. Cheating models

    DEFF Research Database (Denmark)

    Arnoldi, Jakob

    The article discusses the use of algorithmic models for so-called High Frequency Trading (HFT) in finance. HFT is controversial yet widespread in modern financial markets. It is a form of automated trading technology which critics among other things claim can lead to market manipulation. Drawing on...... two cases, this article shows that manipulation more likely happens in the reverse way, meaning that human traders attempt to make algorithms ‘make mistakes’ or ‘mislead’ algos. Thus, it is algorithmic models, not humans, that are manipulated. Such manipulation poses challenges for security exchanges...

  1. Molecular Modeling

    Science.gov (United States)

    Holmes, Jon L.

    1999-06-01

    Molecular modeling has trickled down from the realm of pharmaceutical and research laboratories into the realm of undergraduate chemistry instruction. It has opened avenues for the visualization of chemical concepts that previously were difficult or impossible to convey. I am sure that many of you have developed exercises using the various molecular modeling tools. It is the desire of this Journal to become an avenue for you to share these exercises among your colleagues. It is to this end that Ron Starkey has agreed to edit such a column and to publish not only the description of such exercises, but also the software documents they use. The WWW is the obvious medium to distribute this combination and so accepted submissions will appear online as a feature of JCE Internet. Typical molecular modeling exercise: finding conformation energies. Molecular Modeling Exercises and Experiments is the latest feature column of JCE Internet, joining Conceptual Questions and Challenge Problems, Hal's Picks, and Mathcad in the Chemistry Curriculum. JCE Internet continues to seek submissions in these areas of interest and submissions of general interest. If you have developed materials and would like to submit them, please see our Guide to Submissions for more information. The Chemical Education Resource Shelf, Equipment Buyers Guide, and WWW Site Review would also like to hear about chemistry textbooks and software, equipment, and WWW sites, respectively. Please consult JCE Internet Features to learn more about these resources at JCE Online. Email Announcements Would you like to be informed by email when the latest issue of the Journal is available online? when a new JCE Software title is shipping? when a new JCE Internet article has been published or is available for Open Review? when your subscription is about to expire? A new feature of JCE Online makes this possible. Visit our Guestbook to learn how. When you submit the form on this page, which includes your email address

  2. Modelling language

    CERN Document Server

    Cardey, Sylviane

    2013-01-01

    In response to the need for reliable results from natural language processing, this book presents an original way of decomposing a language(s) in a microscopic manner by means of intra/inter‑language norms and divergences, going progressively from languages as systems to the linguistic, mathematical and computational models, which being based on a constructive approach are inherently traceable. Languages are described with their elements aggregating or repelling each other to form viable interrelated micro‑systems. The abstract model, which contrary to the current state of the art works in int

  3. Molecular modeling

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2009-01-01

    Full Text Available The use of computational chemistry in the development of novel pharmaceuticals is becoming an increasingly important tool. In the past, drugs were simply screened for effectiveness. The recent advances in computing power and the exponential growth of the knowledge of protein structures have made it possible for organic compounds to be tailored to decrease the harmful side effects and increase the potency. This article provides a detailed description of the techniques employed in molecular modeling. Molecular modeling is a rapidly developing discipline, and has been supported by the dramatic improvements in computer hardware and software in recent years.

  4. Lens Model

    DEFF Research Database (Denmark)

    Nash, Ulrik William

    2014-01-01

    Firms consist of people who make decisions to achieve goals. How do these people develop the expectations which underpin the choices they make? The lens model provides one answer to this question. It was developed by cognitive psychologist Egon Brunswik (1952) to illustrate his theory of probabil......Firms consist of people who make decisions to achieve goals. How do these people develop the expectations which underpin the choices they make? The lens model provides one answer to this question. It was developed by cognitive psychologist Egon Brunswik (1952) to illustrate his theory...

  5. Smashnova Model

    OpenAIRE

    Sivaram, C.

    2007-01-01

    An alternate model for gamma ray bursts is suggested. For a white dwarf (WD) and neutron star (NS) very close binary system, the WD (close to Mch) can detonate due to tidal heating, leading to a SN. Material falling on to the NS at relativistic velocities can cause its collapse to a magnetar or quark star or black hole leading to a GRB. As the material smashes on to the NS, it is dubbed the Smashnova model. Here the SN is followed by a GRB. NS impacting a RG (or RSG) (like in Thorne-Zytkow ob...

  6. Modeling Heterogeneity in Consumer Preferences for Select Food Safety Attributes in China

    OpenAIRE

    Ortega, David L.; Wang, H. Holly; Wu, Laping; Olynk, Nicole J.

    2010-01-01

    Food safety issues often arise from problems of asymmetric information between consumers and suppliers with regards to product-specific attributes. Severe food safety scandals were observed recently in China that not only caused direct economic and life loss but also created distrust in the Chinese food system domestically as well as internationally. While much attention has focused on the problems plaguing the Chinese government’s food inspection system, little research has been dedicated to...

  7. Development of a fuzzy qualitative risk assessment model applied to construction industry

    OpenAIRE

    Pinto, Abel Fernando do Nascimento

    2012-01-01

    The construction industry is plagued by occupational risky situations and poor working conditions. Risk Assessment for Occupational Safety (RAOS) is the first and key step to achieve adequate safety levels, particularly to support decision-making in safety programs. Most construction safety efforts are applied informally under the premise that simply allocating more resources to safety management will improve safety on site. Moreover, there are many traditional methods to address RAOS, but...

  8. A short note on integrated assessment modeling approaches : Rejoinder to the review of "Making or breaking climate targets - The AMPERE study on staged accession scenarios for climate policy"

    NARCIS (Netherlands)

    Kriegler, Elmar; Riahi, Keywan; Bauer, Nico; Schwanitz, Valeria Jana; Petermann, Nils; Bosetti, Valentina; Marcucci, Adriana; Otto, Sander; Paroussos, Leonidas; Rao-Skirbekk, Shilpa; Currás, Tabaré Arroyo; Ashina, Shuichi; Bollen, Johannes; Eom, Jiyong; Hamdi-Cherif, Meriem; Longden, Thomas; Kitous, Alban; Méjean, Aurélie; Sano, Fuminori; Schaeffer, Michiel; Wada, Kenichi; Capros, Pantelis; van Vuuren, Detlef P.; Edenhofer, Ottmar; Bertram, Christoph; Bibas, Ruben; Edmonds, Jae; Johnson, Nils; Krey, Volker; Luderer, Gunnar; McCollum, David; Jiang, Kejun

    2015-01-01

    We provide a rejoinder to a review (Rosen, 2015) of our original article "Making or breaking climate targets - the AMPERE study on staged accession scenarios for climate policy" (Kriegler et al., 2015a). We have a substantial disagreement with the content of the review, and feel that it is plagued b

  9. Building Models and Building Modelling

    DEFF Research Database (Denmark)

    Jørgensen, Kaj Asbjørn; Skauge, Jørn

    I rapportens indledende kapitel beskrives de primære begreber vedrørende bygningsmodeller og nogle fundamentale forhold vedrørende computerbaseret modulering bliver opstillet. Desuden bliver forskellen mellem tegneprogrammer og bygnings­model­lerings­programmer beskrevet. Vigtige aspekter om......­lering og bygningsmodeller. Det bliver understreget at modellering bør udføres på flere abstraktions­niveauer og i to dimensioner i den såkaldte modelleringsmatrix. Ud fra dette identificeres de primære faser af bygningsmodel­lering. Dernæst beskrives de basale karakteristika for bygningsmodeller. Heri...... inkluderes en præcisering af begreberne objektorienteret software og objektorienteret modeller. Det bliver fremhævet at begrebet objektbaseret modellering giver en tilstrækkelig og bedre forståelse. Endelig beskrives forestillingen om den ideale bygningsmodel som værende én samlet model, der anvendes gennem...

  10. Defect modelling

    International Nuclear Information System (INIS)

    Calculations, drawing principally on developments at AERE Harwell, of the relaxation about lattice defects are reviewed with emphasis on the techniques required for such calculations. The principles of defect modelling are outlined and various programs developed for defect simulations are discussed. Particular calculations for metals, ionic crystals and oxides, are considered. (UK)

  11. Modelling Entrepreneurship

    NARCIS (Netherlands)

    N. Bosma (Niels); G. de Wit (Gerrit); M.A. Carree (Martin)

    2003-01-01

    textabstractTwo approaches can be distinguished with respect to modelling entrepreneurship: (i) the approach focusing on the net development of the number of entrepreneurs in an equilibrium framework and (ii) the approach focusing on the entries and exits of entrepreneurs. In this paper we unify the

  12. Why Model?

    Directory of Open Access Journals (Sweden)

    Olaf eWolkenhauer

    2014-01-01

    Full Text Available Next generation sequencing technologies are bringing about a renaissance of mining approaches. A comprehensive picture of the genetic landscape of an individual patient will be useful, for example, to identify groups of patients that do or do not respond to certain therapies. The high expectations may however not be satisfied if the number of patient groups with similar characteristics is going to be very large. I therefore doubt that mining sequence data will give us an understanding of why and when therapies work. For understanding the mechanisms underlying diseases, an alternative approach is to model small networks in quantitative mechanistic detail, to elucidate the role of gene and proteins in dynamically changing the functioning of cells. Here an obvious critique is that these models consider too few components, compared to what might be relevant for any particular cell function. I show here that mining approaches and dynamical systems theory are two ends of a spectrum of methodologies to choose from. Drawing upon personal experience in numerous interdisciplinary collaborations, I provide guidance on how to model by discussing the question Why model?

  13. Modeling Muscles

    Science.gov (United States)

    Goodwyn, Lauren; Salm, Sarah

    2007-01-01

    Teaching the anatomy of the muscle system to high school students can be challenging. Students often learn about muscle anatomy by memorizing information from textbooks or by observing plastic, inflexible models. Although these mediums help students learn about muscle placement, the mediums do not facilitate understanding regarding integration of…

  14. Painting models

    Science.gov (United States)

    Baart, F.; Donchyts, G.; van Dam, A.; Plieger, M.

    2015-12-01

    The emergence of interactive art has blurred the line between electronic, computer graphics and art. Here we apply this art form to numerical models. Here we show how the transformation of a numerical model into an interactive painting can both provide insights and solve real world problems. The cases that are used as an example include forensic reconstructions, dredging optimization, barrier design. The system can be fed using any source of time varying vector fields, such as hydrodynamic models. The cases used here, the Indian Ocean (HYCOM), the Wadden Sea (Delft3D Curvilinear), San Francisco Bay (3Di subgrid and Delft3D Flexible Mesh), show that the method used is suitable for different time and spatial scales. High resolution numerical models become interactive paintings by exchanging their velocity fields with a high resolution (>=1M cells) image based flow visualization that runs in a html5 compatible web browser. The image based flow visualization combines three images into a new image: the current image, a drawing, and a uv + mask field. The advection scheme that computes the resultant image is executed in the graphics card using WebGL, allowing for 1M grid cells at 60Hz performance on mediocre graphic cards. The software is provided as open source software. By using different sources for a drawing one can gain insight into several aspects of the velocity fields. These aspects include not only the commonly represented magnitude and direction, but also divergence, topology and turbulence .

  15. Zeebrugge Model

    DEFF Research Database (Denmark)

    Jensen, Morten S.; Frigaard, Peter

    In the following, results from model tests with Zeebrugge breakwater are presented. The objective with these tests is partly to investigate the influence on wave run-up due to a changing waterlevel during a storm. Finally, the influence on wave run-up due to an introduced longshore current...

  16. Turbulence Model

    DEFF Research Database (Denmark)

    Nielsen, Mogens Peter; Shui, Wan; Johansson, Jens

    2011-01-01

    term with stresses depending linearly on the strain rates. This term takes into account the transfer of linear momentum from one part of the fluid to another. Besides there is another term, which takes into account the transfer of angular momentum. Thus the model implies a new definition of turbulence...

  17. Modeling Minds

    DEFF Research Database (Denmark)

    Michael, John

    others' minds. Then (2), in order to bring to light some possible justifications, as well as hazards and criticisms of the methodology of looking time tests, I will take a closer look at the concept of folk psychology and will focus on the idea that folk psychology involves using oneself as a model...

  18. Logic Model

    OpenAIRE

    Taylor, Julie

    2013-01-01

    This paper provides a brief overview of the NSPCC/University of Edinburgh Child Protection Research Centre. It highlights the Centre's work, approach, progress to date and direction of travel. The document includes the Centre's Logic Model which details types of research and outcomes.

  19. Model CAPM

    OpenAIRE

    Burianová, Eva

    2008-01-01

    Cílem první části této bakalářské práce je - pomocí analýzy výchozích textů - teoretické shrnutí ekonomických modelů a teorií, na kterých model CAPM stojí: Markowitzův model teorie portfolia (analýza maximalizace očekávaného užitku a na něm založený model výběru optimálního portfolia), Tobina (rozšíření Markowitzova modelu ? rozdělení výběru optimálního portfolia do dvou fází; nejprve určení optimální kombinace rizikových instrumentů a následná alokace dostupného kapitálu mezi tuto optimální ...

  20. Transport modeling

    Institute of Scientific and Technical Information of China (English)

    R.E. Waltz

    2007-01-01

    @@ There has been remarkable progress during the past decade in understanding and modeling turbulent transport in tokamaks. With some exceptions the progress is derived from the huge increases in computational power and the ability to simulate tokamak turbulence with ever more fundamental and physically realistic dynamical equations, e.g.

  1. Criticality Model

    Energy Technology Data Exchange (ETDEWEB)

    A. Alsaed

    2004-09-14

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of

  2. Information Model for Product Modeling

    Institute of Scientific and Technical Information of China (English)

    焦国方; 刘慎权

    1992-01-01

    The Key problems in product modeling for integrated CAD ∥CAM systems are the information structures and representations of products.They are taking more and more important roles in engineering applications.With the investigation on engineering product information and from the viewpoint of industrial process,in this paper,the information models are proposed and the definitions of the framework of product information are given.And then,the integration and the consistence of product information are discussed by introucing the entity and its instance.As a summary,the information structures described in this paper have many advantage and natures helpful in engineering design.

  3. Optimal input shaping for Fisher identifiability of control-oriented lithium-ion battery models

    Science.gov (United States)

    Rothenberger, Michael J.

    This dissertation examines the fundamental challenge of optimally shaping input trajectories to maximize parameter identifiability of control-oriented lithium-ion battery models. Identifiability is a property from information theory that determines the solvability of parameter estimation for mathematical models using input-output measurements. This dissertation creates a framework that exploits the Fisher information metric to quantify the level of battery parameter identifiability, optimizes this metric through input shaping, and facilitates faster and more accurate estimation. The popularity of lithium-ion batteries is growing significantly in the energy storage domain, especially for stationary and transportation applications. While these cells have excellent power and energy densities, they are plagued with safety and lifespan concerns. These concerns are often resolved in the industry through conservative current and voltage operating limits, which reduce the overall performance and still lack robustness in detecting catastrophic failure modes. New advances in automotive battery management systems mitigate these challenges through the incorporation of model-based control to increase performance, safety, and lifespan. To achieve these goals, model-based control requires accurate parameterization of the battery model. While many groups in the literature study a variety of methods to perform battery parameter estimation, a fundamental issue of poor parameter identifiability remains apparent for lithium-ion battery models. This fundamental challenge of battery identifiability is studied extensively in the literature, and some groups are even approaching the problem of improving the ability to estimate the model parameters. The first approach is to add additional sensors to the battery to gain more information that is used for estimation. The other main approach is to shape the input trajectories to increase the amount of information that can be gained from input

  4. Molecular Modelling

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2009-12-01

    Full Text Available

    The use of computational chemistry in the development of novel pharmaceuticals is becoming an increasingly important
    tool. In the past, drugs were simply screened for effectiveness. The recent advances in computing power and
    the exponential growth of the knowledge of protein structures have made it possible for organic compounds to tailored to
    decrease harmful side effects and increase the potency. This article provides a detailed description of the techniques
    employed in molecular modeling. Molecular modelling is a rapidly developing discipline, and has been supported from
    the dramatic improvements in computer hardware and software in recent years.

  5. Leadership model

    OpenAIRE

    Almeida, Leandro S.; José Fernando A. Cruz; Ferreira, Helena Isabel dos Santos Ribeiro; Pinto, Alberto

    2011-01-01

    The Theory of Planned Behavior studies the decision-making mechanisms of individuals. We propose the Nash Equilibria as one, of many, possible mechanisms of transforming human intentions in behavior. This process corresponds to the best strategic individual decision taking in account the collective response. We built a game theoretical model to understand the role of leaders in decision-making of individuals or groups. We study the characteristics of the leaders that can have a...

  6. Model Uncertainty

    OpenAIRE

    Clyde, Merlise; George, Edward I.

    2004-01-01

    The evolution of Bayesian approaches for model uncertainty over the past decade has been remarkable. Catalyzed by advances in methods and technology for posterior computation, the scope of these methods has widened substantially. Major thrusts of these developments have included new methods for semiautomatic prior specification and posterior exploration. To illustrate key aspects of this evolution, the highlights of some of these developments are described.

  7. Modeling fatigue.

    OpenAIRE

    Sumner, Walton; Xu, Jin Zhong

    2002-01-01

    The American Board of Family Practice is developing a patient simulation program to evaluate diagnostic and management skills. The simulator must give temporally and physiologically reasonable answers to symptom questions such as "Have you been tired?" A three-step process generates symptom histories. In the first step, the simulator determines points in time where it should calculate instantaneous symptom status. In the second step, a Bayesian network implementing a roughly physiologic model...

  8. Modeling biomembranes.

    Energy Technology Data Exchange (ETDEWEB)

    Plimpton, Steven James; Heffernan, Julieanne; Sasaki, Darryl Yoshio; Frischknecht, Amalie Lucile; Stevens, Mark Jackson; Frink, Laura J. Douglas

    2005-11-01

    Understanding the properties and behavior of biomembranes is fundamental to many biological processes and technologies. Microdomains in biomembranes or ''lipid rafts'' are now known to be an integral part of cell signaling, vesicle formation, fusion processes, protein trafficking, and viral and toxin infection processes. Understanding how microdomains form, how they depend on membrane constituents, and how they act not only has biological implications, but also will impact Sandia's effort in development of membranes that structurally adapt to their environment in a controlled manner. To provide such understanding, we created physically-based models of biomembranes. Molecular dynamics (MD) simulations and classical density functional theory (DFT) calculations using these models were applied to phenomena such as microdomain formation, membrane fusion, pattern formation, and protein insertion. Because lipid dynamics and self-organization in membranes occur on length and time scales beyond atomistic MD, we used coarse-grained models of double tail lipid molecules that spontaneously self-assemble into bilayers. DFT provided equilibrium information on membrane structure. Experimental work was performed to further help elucidate the fundamental membrane organization principles.

  9. Technological Forecasting---Model Selection, Model Stability, and Combining Models

    OpenAIRE

    Nigel Meade; Towhidul Islam

    1998-01-01

    The paper identifies 29 models that the literature suggests are appropriate for technological forecasting. These models are divided into three classes according to the timing of the point of inflexion in the innovation or substitution process. Faced with a given data set and such a choice, the issue of model selection needs to be addressed. Evidence used to aid model selection is drawn from measures of model fit and model stability. An analysis of the forecasting performance of these models u...

  10. Model Construct Based Enterprise Model Architecture and Its Modeling Approach

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In order to support enterprise integration, a kind of model construct based enterprise model architecture and its modeling approach are studied in this paper. First, the structural makeup and internal relationships of enterprise model architecture are discussed. Then, the concept of reusable model construct (MC) which belongs to the control view and can help to derive other views is proposed. The modeling approach based on model construct consists of three steps, reference model architecture synthesis, enterprise model customization, system design and implementation. According to MC based modeling approach a case study with the background of one-kind-product machinery manufacturing enterprises is illustrated. It is shown that proposal model construct based enterprise model architecture and modeling approach are practical and efficient.

  11. A Model

    Institute of Scientific and Technical Information of China (English)

    Liu Zhiyang

    2011-01-01

    Similar to ISO Technical Committees,SAC Technical Committees undertake the management and coordination of standard's development and amendments in various sectors in industry,playing the role as a bridge among enterprises,research institutions and the governmental standardization administration.How to fully play the essential role is the vital issue SAC has been committing to resolve.Among hundreds of SAC TCs,one stands out in knitting together those isolated,scattered,but highly competitive enterprises in the same industry with the "Standards" thread,and achieving remarkable results in promoting industry development with standardization.It sets a role model for other TCs.

  12. Transcriptional regulatory network refinement and quantification through kinetic modeling, gene expression microarray data and information theory

    Directory of Open Access Journals (Sweden)

    Tuncay Kagan

    2007-01-01

    Full Text Available Abstract Background Gene expression microarray and other multiplex data hold promise for addressing the challenges of cellular complexity, refined diagnoses and the discovery of well-targeted treatments. A new approach to the construction and quantification of transcriptional regulatory networks (TRNs is presented that integrates gene expression microarray data and cell modeling through information theory. Given a partial TRN and time series data, a probability density is constructed that is a functional of the time course of transcription factor (TF thermodynamic activities at the site of gene control, and is a function of mRNA degradation and transcription rate coefficients, and equilibrium constants for TF/gene binding. Results Our approach yields more physicochemical information that compliments the results of network structure delineation methods, and thereby can serve as an element of a comprehensive TRN discovery/quantification system. The most probable TF time courses and values of the aforementioned parameters are obtained by maximizing the probability obtained through entropy maximization. Observed time delays between mRNA expression and activity are accounted for implicitly since the time course of the activity of a TF is coupled by probability functional maximization, and is not assumed to be proportional to expression level of the mRNA type that translates into the TF. This allows one to investigate post-translational and TF activation mechanisms of gene regulation. Accuracy and robustness of the method are evaluated. A kinetic formulation is used to facilitate the analysis of phenomena with a strongly dynamical character while a physically-motivated regularization of the TF time course is found to overcome difficulties due to omnipresent noise and data sparsity that plague other methods of gene expression data analysis. An application to Escherichia coli is presented. Conclusion Multiplex time series data can be used for the

  13. From model checking to model measuring

    OpenAIRE

    Henzinger, Thomas A.; Otop, Jan

    2013-01-01

    We define the model-measuring problem: given a model $M$ and specification~$\\varphi$, what is the maximal distance $\\rho$ such that all models $M'$ within distance $\\rho$ from $M$ satisfy (or violate)~$\\varphi$. The model measuring problem presupposes a distance function on models. We concentrate on automatic distance functions, which are defined by weighted automata. The model-measuring problem subsumes several generalizations of the classical model-checking problem, in particular, qu...

  14. The ARCON modeling framework

    NARCIS (Netherlands)

    H. Afsarmanesh; L.M. Camarinha-Matos

    2008-01-01

    A framework is defined for ARCON reference modeling, introducing multiple modeling perspectives of: Environment characteristics, life cycle stages, and modeling intents. This novel modeling framework takes into account contributions from previous related works, mainly on enterprise modeling, and ext

  15. ModelWizard: Toward Interactive Model Construction

    OpenAIRE

    Hutchison, Dylan

    2016-01-01

    Data scientists engage in model construction to discover machine learning models that well explain a dataset, in terms of predictiveness, understandability and generalization across domains. Questions such as "what if we model common cause Z" and "what if Y's dependence on X reverses" inspire many candidate models to consider and compare, yet current tools emphasize constructing a final model all at once. To more naturally reflect exploration when debating numerous models, we propose an inter...

  16. Towards a Multi Business Model Innovation Model

    DEFF Research Database (Denmark)

    Lindgren, Peter; Jørgensen, Rasmus

    2012-01-01

    This paper studies the evolution of business model (BM) innovations related to a multi business model framework. The paper tries to answer the research questions: • What are the requirements for a multi business model innovation model (BMIM)? • How should a multi business model innovation model...... look like? Different generations of BMIMs are initially studied in the context of laying the baseline for how next generation multi BM Innovation model (BMIM) should look like. All generations of models are analyzed with the purpose of comparing the characteristics and challenges of previous...

  17. Impedance model for nanostructures

    Directory of Open Access Journals (Sweden)

    R. S. Akhmedov

    2007-06-01

    Full Text Available The application of the impedance model for nanoelectronic quantum-mechanical structures modelling is described. Characteristics illustrating the efficiency of the model are presented.

  18. Three-Dimensional Vp and Vs Models of Continental China From Joint Inversion of Body Wave, Surface Wave, and Gravity Data

    Science.gov (United States)

    van der Hilst, R. D.; Zhang, H.; Maceira, M.; Chen, F.; Shen, W.; Fang, H.; Yao, H.

    2015-12-01

    To improve our understanding of the complex geological structure of continental China we need accurate depictions of the 3D structure of the crust and lithospheric mantle. Taking advantage of the increasingly dense seismograph coverage in continental China, several Vp and Vs models at various scales and resolutions have been obtained over the past decades. Tomographic models based either on body wave travel times or surface waves differ, however, in important aspects, especially for the structure beneath the Tibetan Plateau. Internally consistent Vp and Vs models are needed to resolve these differences. Body wave travel time tomography and surface wave tomography each have strengths and weaknesses. Travel time tomography can yield higher resolution in regions of dense path coverage, and it generally has excellent lateral resolution beneath regions of high seismic activity or dense station distribution. In many other regions, however, the shallow subsurface cannot be resolved adequately by direct P or S travel times. In contrast, surface wave data (from earthquakes or ambient noise) generally yields better radial resolution and has better potential for resolving shallow mantle structure beneath regions that are aseismic or which are void of seismograph stations. Gravity measurements can provide constraints on spatial variations in (mass) density, but like other potential field methods interpretation of gravity anomalies is plagued by substantial ambiguity. Indeed, weak and broad structures in the shallow subsurface can produce the same gravity signal (at the surface) as a small, strong density anomaly at a larger depth. To benefit from the complementary sampling of the different data, we have developed a joint inversion scheme that uses body wave travel times, surface wave dispersion, and satellite gravity data to invert for spatial variations in Vp, Vs, and mass density (with the seismic and gravity data linked through an empirical relationship between wavespeed

  19. The IMACLIM model; Le modele IMACLIM

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This document provides annexes to the IMACLIM model which propose an actualized description of IMACLIM, model allowing the design of an evaluation tool of the greenhouse gases reduction policies. The model is described in a version coupled with the POLES, technical and economical model of the energy industry. Notations, equations, sources, processing and specifications are proposed and detailed. (A.L.B.)

  20. Building Mental Models by Dissecting Physical Models

    Science.gov (United States)

    Srivastava, Anveshna

    2016-01-01

    When students build physical models from prefabricated components to learn about model systems, there is an implicit trade-off between the physical degrees of freedom in building the model and the intensity of instructor supervision needed. Models that are too flexible, permitting multiple possible constructions require greater supervision to…

  1. Forward model nonlinearity versus inverse model nonlinearity

    Science.gov (United States)

    Mehl, S.

    2007-01-01

    The issue of concern is the impact of forward model nonlinearity on the nonlinearity of the inverse model. The question posed is, "Does increased nonlinearity in the head solution (forward model) always result in increased nonlinearity in the inverse solution (estimation of hydraulic conductivity)?" It is shown that the two nonlinearities are separate, and it is not universally true that increased forward model nonlinearity increases inverse model nonlinearity. ?? 2007 National Ground Water Association.

  2. Modeling for Sustainability

    OpenAIRE

    Combemale, Benoit; Cheng, Betty H.C.; Moreira, Ana; Bruel, Jean-Michel; Gray, Jeff

    2015-01-01

    Various disciplines use models for different purposes. An engineering model, including a software engineering model, is often developed to guide the construction of a non-existent system. A scientific model is created to better understand a natural phenomenon (i.e., an already existing system). An engineering model may incorporate scientific models to build a system. Sustainability is an area that requires both types of models. Both engineering and scientific models have been used to support ...

  3. Comparative Protein Structure Modeling Using MODELLER.

    Science.gov (United States)

    Webb, Benjamin; Sali, Andrej

    2016-01-01

    Comparative protein structure modeling predicts the three-dimensional structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and how to use the ModBase database of such models, and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. © 2016 by John Wiley & Sons, Inc. PMID:27322406

  4. Comparative Protein Structure Modeling Using MODELLER.

    Science.gov (United States)

    Webb, Benjamin; Sali, Andrej

    2016-06-20

    Comparative protein structure modeling predicts the three-dimensional structure of a given protein sequence (target) based primarily on its alignment to one or more proteins of known structure (templates). The prediction process consists of fold assignment, target-template alignment, model building, and model evaluation. This unit describes how to calculate comparative models using the program MODELLER and how to use the ModBase database of such models, and discusses all four steps of comparative modeling, frequently observed errors, and some applications. Modeling lactate dehydrogenase from Trichomonas vaginalis (TvLDH) is described as an example. The download and installation of the MODELLER software is also described. © 2016 by John Wiley & Sons, Inc.

  5. Concept Modeling vs. Data modeling in Practice

    DEFF Research Database (Denmark)

    Madsen, Bodil Nistrup; Erdman Thomsen, Hanne

    2015-01-01

    This chapter shows the usefulness of terminological concept modeling as a first step in data modeling. First, we introduce terminological concept modeling with terminological ontologies, i.e. concept systems enriched with characteristics modeled as feature specifications. This enables a formal...... account of the inheritance of characteristics and allows us to introduce a number of principles and constraints which render concept modeling more coherent than earlier approaches. Second, we explain how terminological ontologies can be used as the basis for developing conceptual and logical data models....... We also show how to map from the various elements in the terminological ontology to elements in the data models, and explain the differences between the models. Finally the usefulness of terminological ontologies as a prerequisite for IT development and data modeling is illustrated with examples from...

  6. The Power of the Point: Benjamin Franklin, the Lightning Rod and Two Misconceptions That Have Plagued Us to This Day

    Science.gov (United States)

    Aulich, G. D.; Moore, C. B.; Rison, W.

    2006-12-01

    Most people know that Ben Franklin invented the lightning rod and that his rods have successfully protected structures for over 250 years. What people don't know is that he invented them on the basis of two misconceptions. The first, that an elevated pointed conductor would discharge a thunderstorm, thereby preventing lightning. The second, that, should the first process fail, the elevated conductor, by virtue of its pointed tip, would serve as a preferred receptor for any lightning strokes that did occur. It has long been known that grounded, elevated, pointed conductors can not discharge thunderstorms and experiments conducted at the Langmuir Laboratory during the 1990s have shown that moderately blunt, rather than pointed, rods are the best receptors for lightning strokes. Nevertheless, Franklin's incorrect ideas about lightning rods persist in many minds, even among some people in the lightning protection business.

  7. Genotyping and phylogenetic analysis of Yersinia pestis by MLVA: insights into the worldwide expansion of Central Asia plague foci.

    Directory of Open Access Journals (Sweden)

    Yanjun Li

    Full Text Available BACKGROUND: The species Yersinia pestis is commonly divided into three classical biovars, Antiqua, Medievalis, and Orientalis, belonging to subspecies pestis pathogenic for human and the (atypical non-human pathogenic biovar Microtus (alias Pestoides including several non-pestis subspecies. Recent progress in molecular typing methods enables large-scale investigations in the population structure of this species. It is now possible to test hypotheses about its evolution which were proposed decades ago. For instance the three classical biovars of different geographical distributions were suggested to originate from Central Asia. Most investigations so far have focused on the typical pestis subspecies representatives found outside of China, whereas the understanding of the emergence of this human pathogen requires the investigation of strains belonging to subspecies pestis from China and to the Microtus biovar. METHODOLOGY/PRINCIPAL FINDINGS: Multi-locus VNTR analysis (MLVA with 25 loci was performed on a collection of Y. pestis isolates originating from the majority of the known foci worldwide and including typical rhamnose-negative subspecies pestis as well as rhamnose-positive subspecies pestis and biovar Microtus. More than 500 isolates from China, the Former Soviet Union (FSU, Mongolia and a number of other foci around the world were characterized and resolved into 350 different genotypes. The data revealed very close relationships existing between some isolates from widely separated foci as well as very high diversity which can conversely be observed between nearby foci. CONCLUSIONS/SIGNIFICANCE: The results obtained are in full agreement with the view that the Y. pestis subsp. pestis pathogenic for humans emerged in the Central Asia region between China, Kazakhstan, Russia and Mongolia, only three clones of which spread out of Central Asia. The relationships among the strains in China, Central Asia and the rest of the world based on the MLVA25 assay provide an unprecedented view on the expansion and microevolution of Y. pestis.

  8. An outbreak of duck viral enteritis (duck plague) in domestic Muscovy ducks (Cairina moschata domesticus) in Illinois.

    Science.gov (United States)

    Campagnolo, E R; Banerjee, M; Panigrahy, B; Jones, R L

    2001-01-01

    Duck viral enteritis (DVE) was diagnosed in an outbreak of the disease in a resident population of Muscovy ducks (Cairina moschata domesticus) on a privately owned multispecies game bird production facility in Illinois, where it claimed 625 ducks. This disease condition had not been reported previously in domestic ducks in Illinois. Although other varieties and age groups of domestic waterfowl (i.e., black ducks, rhumen ducks, Pekin ducks, ducklings, and geese) were present on the game bird farm, the morbidity and mortality (100%) in this epornitic was solely limited to adult ducks of the Muscovy lineage. The clinical signs in the affected ducks were lethargy, diarrhea, dehydration, and death within 2-3 hr of onset of symptoms. Gross pathologic changes were nonspecific and included ecchymotic hemorrhage, effusion of fluid and blood within body cavities reflective of an acute systemic infectious disease. Light microscopic findings were necrosis of primarily digestive lining epithelium and variable lymphohistiocytic infiltration within mucosal and serosal connective tissues. Intranuclear inclusions resembling characteristic herpetic (i.e., Cowdry type A) inclusions were observed primarily in the digestive, respiratory, and reproductive tracts; liver; and spleen. Esophageal candidiasis, bacteriosis, and systemic Pasteurella anatipestifer infections, thought to be concurrent or opportunistic infections, were present in several ducks. DVE virus was demonstrated in infected Muscovy duck embryo fibroblast cells by direct DVE virus-specific fluorescent antibody staining. PMID:11417839

  9. 籽用南瓜鼠害防治技术%Techniques of Controlling Plagues of Rats in Seed Pumpkin

    Institute of Scientific and Technical Information of China (English)

    方仁柱

    2008-01-01

    籽用南瓜以其种籽(白瓜籽)经济价值高、销售快、收益大,颇受农民欢迎。目前桦南、宝清、鸡西等地已种植5万多hm2,成为当地重要的经济支柱产业。然而在生产和贮藏过程中,鼠类对籽用南瓜危害较大。春天咬食播种种子及幼苗,夏季糟蹋植株、幼瓜,秋季掏食大瓜,冬季则安居于库房,盗食瓜籽。老鼠咬嗑瓜籽技术高超,去皮食仁,速度奇快,而且常将其包装麻袋等咬成千疮百孔;鼠粪、尿液污染瓜籽,失去经济价值。鼠类还可在库房地下挖洞、掏墙,雨季灌水,引起地基下沉。仓库倒塌。

  10. 试析1920年湖南瘟疫%A Primary Study on Plagues in Hunan in 1920

    Institute of Scientific and Technical Information of China (English)

    杨湘容

    2001-01-01

    1920年是湖南省多事之年,兵灾、水灾、疫灾同时并发,有如雪上加霜.本文从是年湖南瘟疫产生的原因、特点、后果及防治各方面进行初步探讨.认为天灾与人祸互为因果,不革新政治、发展生产和科技是无法战胜瘟疫的.

  11. Accounting Problems Plague European and American Telecos%会计问题困扰欧美电信公司

    Institute of Scientific and Technical Information of China (English)

    钱静

    2002-01-01

    @@ 环球电讯(Global Crossing)轰然倒下.闻讯赶来的债权人和投资者却忽然发现,这家公司其实早已经一文不值了,它破产时申报的220亿元资产被怀疑只有10亿~20亿美元的实际市场价值,而在鼎盛时期,环球电讯的市值最高曾经达到800亿美元.更为严重的是,它"以光速衰败"的现象引发了投资者对整个欧美电信业的信任危机,人们疑虑,在资产负债表上看到的资产额的真实价值到底是多少?令人眩目的收入和利润增长率到底在多大程度上反映了公司竞争力的增强?再进一步说,在现有的会计规则下,那些传统的财务表格到底还能不能反映经济活动的实际状况,对投资人和债权人还有没有参考价值?

  12. Diagnosis, Prevention and Treatment of Dog Plague with Fever%犬瘟热的诊断与防治

    Institute of Scientific and Technical Information of China (English)

    李景芝

    2007-01-01

    犬瘟热(canine Distemper CD)是由犬瘟热病毒(Canine Distemper Virus CD)引起的一种高度接触性传染病.此病在世界范围内流行,一年四季都发生.其传染性强,发病率高,临床症状多样,易继发其他细菌和病毒的混合感染和2次感染,死亡率高达80%.故临床上仅以呼吸道症状、消化道症状和眼部表现进行判断,有一定误诊率.采取对死亡病犬剖检观察,对未死亡的犬进行实验室诊断,可对犬瘟热进行确诊.对CD统计表明,患CD犬的数量占全年患传染病的犬只数量的30%,因此,CD是当前对宠物饲养业、经济动物养殖业和动物园观赏业危害极大的疾病.故在做好预防接种的前提下,提高对患病犬的诊断水平和治疗水平,是减少CDV危害的重要途径.

  13. Polymerase chain reaction (PCR) identification of rodent blood meals confirms host sharing by flea vectors of plague

    NARCIS (Netherlands)

    Franklin, Heather A.; Stapp, Paul; Cohen, Amybeth

    2010-01-01

    Elucidating feeding relationships between hosts and parasites remains a significant challenge in studies of the ecology of infectious diseases, especially those involving small or cryptic vectors. Black-tailed prairie dogs (Cynomys ludovicianus) are a species of conservation importance in the North

  14. Modelling of Hydraulic Robot

    DEFF Research Database (Denmark)

    Madsen, Henrik; Zhou, Jianjun; Hansen, Lars Henrik

    1997-01-01

    This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application of the l......This paper describes a case study of identifying the physical model (or the grey box model) of a hydraulic test robot. The obtained model is intended to provide a basis for model-based control of the robot. The physical model is formulated in continuous time and is derived by application...

  15. An experimental and modeling study of grain-scale uranium desorption from field-contaminated sediments and the potential influence of microporosity on mass-transfer

    Science.gov (United States)

    Stoliker, D.; Liu, C.; Kent, D. B.; Zachara, J. M.

    2012-12-01

    The aquifer below the 300-Area of the Hanford site (Richland, WA, USA) is plagued by a persistent plume of dissolved uranium (U(VI)) in excess of the Environmental Protection Agency drinking water maximum contamination level even after the removal of highly contaminated sediments. The aquifer sediments in the seasonally saturated lower vadose zone act as both a source and sink for uranium during stage changes in the nearby Columbia River. Diffusion limitation of uranium mass-transfer within these sediments has been cited as a potential cause of the plume's persistence. Equilibrium U(VI) sorption is a strong function of variable chemical conditions, especially carbonate, hydrogen, and uranyl ion activities. Field-contaminated sediments from the site require up to 1,000 hours to reach equilibrium in static batch reactors. Increases in U(VI) concentrations over longer time-scales result from changes in chemical conditions, which drive reactions with sediments that favor U(VI) desorption. Grain-scale U(VI) sorption/desorption rates are slow, likely owing to diffusion of U(VI) and other solutes through intra-granular pore domains. In order to improve understanding of the impact of intra-granular diffusion and chemical reactions controlling grain-scale U(VI) release, experiments were conducted on individual particle size fractions of a displacement from equilibrium and multiple diffusion domains were described with a two-parameter lognormal distribution of mass-transfer rate coefficients. Parameters describing mass transfer were the same for all size fractions <2 mm but differed for the largest (2-8 mm) size fraction. The evolution of pH, along with dissolved cation and carbonate concentrations, was modeled using equilibrium cation exchange, rate-limited calcite dissolution, aerobic respiration, and silica dissolution. Desorption and chemical reaction models calibrated with individual size fractions predicted U(VI) and chemical composition as a function of time for the

  16. Business Model Innovation

    OpenAIRE

    Dodgson, Mark; Gann, David; Phillips, Nelson; Massa, Lorenzo; Tucci, Christopher

    2014-01-01

    The chapter offers a broad review of the literature at the nexus between Business Models and innovation studies, and examines the notion of Business Model Innovation in three different situations: Business Model Design in newly formed organizations, Business Model Reconfiguration in incumbent firms, and Business Model Innovation in the broad context of sustainability. Tools and perspectives to make sense of Business Models and support managers and entrepreneurs in dealing with Business Model ...

  17. Model Manipulation for End-User Modelers

    DEFF Research Database (Denmark)

    Acretoaie, Vlad

    End-user modelers are domain experts who create and use models as part of their work. They are typically not Software Engineers, and have little or no programming and meta-modeling experience. However, using model manipulation languages developed in the context of Model-Driven Engineering often...... requires such experience. These languages are therefore only used by a small subset of the modelers that could, in theory, benefit from them. The goals of this thesis are to substantiate this observation, introduce the concepts and tools required to overcome it, and provide empirical evidence in support...... of these proposals. To achieve its first goal, the thesis presents the findings of a Systematic Mapping Study showing that human factors topics are scarcely and relatively poorly addressed in model transformation research. Motivated by these findings, the thesis explores the requirements of end-user modelers...

  18. Lead Halide Perovskite Photovoltaic as a Model p-i-n Diode.

    Science.gov (United States)

    Miyano, Kenjiro; Tripathi, Neeti; Yanagida, Masatoshi; Shirai, Yasuhiro

    2016-02-16

    The lead halide perovskite photovoltaic cells, especially the iodide compound CH3NH3PbI3 family, exhibited enormous progress in the energy conversion efficiency in the past few years. Although the first attempt to use the perovskite was as a sensitizer in a dye-sensitized solar cell, it has been recognized at the early stage of the development that the working of the perovskite photovoltaics is akin to that of the inorganic thin film solar cells. In fact, theoretically perovskite is always treated as an ordinary direct band gap semiconductor and hence the perovskite photovoltaics as a p-i-n diode. Despite this recognition, research effort along this line of thought is still in pieces and incomplete. Different measurements have been applied to different types of devices (different not only in the materials but also in the cell structures), making it difficult to have a coherent picture. To make the situation worse, the perovskite photovoltaics have been plagued by the irreproducible optoelectronic properties, most notably the sweep direction dependent current-voltage relationship, the hysteresis problem. Under such circumstances, it is naturally very difficult to analyze the data. Therefore, we set out to make hysteresis-free samples and apply time-tested models and numerical tools developed in the field of inorganic semiconductors. A series of electrical measurements have been performed on one type of CH3NH3PbI3 photovoltaic cells, in which a special attention was paid to ensure that their electronic reproducibility was better than the fitting error in the numerical analysis. The data can be quantitatively explained in terms of the established models of inorganic semiconductors: current/voltage relationship can be very well described by a two-diode model, while impedance spectroscopy revealed the presence of a thick intrinsic layer with the help of a numerical solver, SCAPS, developed for thin film solar cell analysis. These results point to that CH3NH3PbI3 is an

  19. Lead Halide Perovskite Photovoltaic as a Model p-i-n Diode.

    Science.gov (United States)

    Miyano, Kenjiro; Tripathi, Neeti; Yanagida, Masatoshi; Shirai, Yasuhiro

    2016-02-16

    The lead halide perovskite photovoltaic cells, especially the iodide compound CH3NH3PbI3 family, exhibited enormous progress in the energy conversion efficiency in the past few years. Although the first attempt to use the perovskite was as a sensitizer in a dye-sensitized solar cell, it has been recognized at the early stage of the development that the working of the perovskite photovoltaics is akin to that of the inorganic thin film solar cells. In fact, theoretically perovskite is always treated as an ordinary direct band gap semiconductor and hence the perovskite photovoltaics as a p-i-n diode. Despite this recognition, research effort along this line of thought is still in pieces and incomplete. Different measurements have been applied to different types of devices (different not only in the materials but also in the cell structures), making it difficult to have a coherent picture. To make the situation worse, the perovskite photovoltaics have been plagued by the irreproducible optoelectronic properties, most notably the sweep direction dependent current-voltage relationship, the hysteresis problem. Under such circumstances, it is naturally very difficult to analyze the data. Therefore, we set out to make hysteresis-free samples and apply time-tested models and numerical tools developed in the field of inorganic semiconductors. A series of electrical measurements have been performed on one type of CH3NH3PbI3 photovoltaic cells, in which a special attention was paid to ensure that their electronic reproducibility was better than the fitting error in the numerical analysis. The data can be quantitatively explained in terms of the established models of inorganic semiconductors: current/voltage relationship can be very well described by a two-diode model, while impedance spectroscopy revealed the presence of a thick intrinsic layer with the help of a numerical solver, SCAPS, developed for thin film solar cell analysis. These results point to that CH3NH3PbI3 is an

  20. Model Checking of Boolean Process Models

    OpenAIRE

    Schneider, Christoph; Wehler, Joachim

    2011-01-01

    In the field of Business Process Management formal models for the control flow of business processes have been designed since more than 15 years. Which methods are best suited to verify the bulk of these models? The first step is to select a formal language which fixes the semantics of the models. We adopt the language of Boolean systems as reference language for Boolean process models. Boolean systems form a simple subclass of coloured Petri nets. Their characteristics are low tokens to mode...

  1. From Product Models to Product State Models

    DEFF Research Database (Denmark)

    Larsen, Michael Holm

    1999-01-01

    A well-known technology designed to handle product data is Product Models. Product Models are in their current form not able to handle all types of product state information. Hence, the concept of a Product State Model (PSM) is proposed. The PSM and in particular how to model a PSM is the Research...... Object for this project. In the presentation, benefits and challenges of the PSM will be presented as a basis for the discussion....

  2. Measurement and Modeling: Infectious Disease Modeling

    NARCIS (Netherlands)

    Kretzschmar, MEE

    2016-01-01

    After some historical remarks about the development of mathematical theory for infectious disease dynamics we introduce a basic mathematical model for the spread of an infection with immunity. The concepts of the model are explained and the model equations are derived from first principles. Using th

  3. Molecular Models: Construction of Models with Magnets

    OpenAIRE

    Kalinovčić P.

    2015-01-01

    Molecular models are indispensable tools in teaching chemistry. Beside their high price, commercially available models are generally too small for classroom demonstration. This paper suggests how to make space-filling (callote) models from Styrofoam with magnetic balls as connectors and disc magnets for showing molecular polarity

  4. An improved neutral diffusion model and numerical solution of the two dimensional edge plasma fluid equations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Prinja, A.K.

    1998-09-01

    In this work, it has been shown that, for the given sets of parameters (transport coefficients), the Tangent-Predictor (TP) continuation method, which was used in the coarsest grid, works remarkably well. The problems in finding an initial guess that resides well within Newton`s method radius of convergence are alleviated by correcting the initial guess by the predictor step of the TP method. The TP method works well also in neutral gas puffing and impurity simulations. The neutral gas puffing simulation is performed by systematically increasing the fraction of puffing rate according to the TP method until it reaches a desired condition. Similarly, the impurity simulation characterized by using the fraction of impurity density as the continuation parameter, is carried out in line with the TP method. Both methods show, as expected, a better performance than the classical embedding (CE) method. The convergence criteria {epsilon} is set to be 10{sup {minus}9} based on the fact that lower value of {epsilon} does not alter the solution significantly. Correspondingly, the number of Newton`s iterations in the corrector step of the TP method decrease substantially, an extra point in terms of code speed. The success of the TP method enlarges the possibility of including other sets of parameters (operations and physics). With the availability of the converged coarsest grid solution, the next forward step to the multigrid cycle becomes possible. The multigrid method shows that the memory storage problems that plagued the application of Newton`s method on fine grids, are of no concern. An important result that needs to be noted here is the performance of the FFCD model. The FFCD model is relatively simple and is based on the overall results the model has shown to predict different divertor plasma parameters. The FFCD model treats exactly the implementation of the deep penetration of energetic neutrals emerging from the divertor plate. The resulting ionization profiles are

  5. QSMSR QUALITATIVE MODEL

    Directory of Open Access Journals (Sweden)

    Tahir Abdullah

    2012-02-01

    Full Text Available Software architecture design and requirement engineering are core and independent areas of engineering. A lot of research, education and practice are carried on Requirement elicitation and doing refine it, but it is a major issue of engineering. QSMSR model act as a bridge between requirement and design there is a huge gap between these two areas of software architecture and requirement engineering. The QSMSR model divide into two sub model qualitative model and Principal model in this research we focus on Qualitative model which further divide into two sub models fabricated model and classified model. Classified model make the sub groups of the role and match it with components. The Fabricated model link QSMSR Principal Model to an architecture design. At the end it provides the QSMSR Architecture model of the system as output.

  6. Understandings of 'Modelling'

    DEFF Research Database (Denmark)

    Andresen, Mette

    2007-01-01

    This paper meets the common critique of the teaching of non-authentic modelling in school mathematics. In the paper, non-authentic modelling is related to a change of view on the intentions of modelling from knowledge about applications of mathematical models to modelling for concept formation. Non......-authentic modelling is also linked with the potentials of exploration of ready-made models as a forerunner for more authentic modelling processes. The discussion includes analysis of an episode of students? work in the classroom, which serves to illustrate how concept formation may be linked to explorations of a non......-authentic model....

  7. Modelling freight transport

    NARCIS (Netherlands)

    Tavasszy, L.A.; Jong, G. de

    2014-01-01

    Freight Transport Modelling is a unique new reference book that provides insight into the state-of-the-art of freight modelling. Focusing on models used to support public transport policy analysis, Freight Transport Modelling systematically introduces the latest freight transport modelling approache

  8. Model-Independent Diffs

    DEFF Research Database (Denmark)

    Könemann, Patrick

    just contain a list of strings, one for each line, whereas the structure of models is defined by their meta models. There are tools available which are able to compute the diff between two models, e.g. RSA or EMF Compare. However, their diff is not model-independent, i.e. it refers to the models...

  9. "Bohr's Atomic Model."

    Science.gov (United States)

    Willden, Jeff

    2001-01-01

    "Bohr's Atomic Model" is a small interactive multimedia program that introduces the viewer to a simplified model of the atom. This interactive simulation lets students build an atom using an atomic construction set. The underlying design methodology for "Bohr's Atomic Model" is model-centered instruction, which means the central model of the…

  10. Modelling Foundations and Applications

    DEFF Research Database (Denmark)

    and selected from 81 submissions. Papers on all aspects of MDE were received, including topics such as architectural modelling and product lines, code generation, domain-specic modeling, metamodeling, model analysis and verication, model management, model transformation and simulation. The breadth of topics...

  11. Solicited abstract: Global hydrological modeling and models

    Science.gov (United States)

    Xu, Chong-Yu

    2010-05-01

    The origins of rainfall-runoff modeling in the broad sense can be found in the middle of the 19th century arising in response to three types of engineering problems: (1) urban sewer design, (2) land reclamation drainage systems design, and (3) reservoir spillway design. Since then numerous empirical, conceptual and physically-based models are developed including event based models using unit hydrograph concept, Nash's linear reservoir models, HBV model, TOPMODEL, SHE model, etc. From the late 1980s, the evolution of global and continental-scale hydrology has placed new demands on hydrologic modellers. The macro-scale hydrological (global and regional scale) models were developed on the basis of the following motivations (Arenll, 1999). First, for a variety of operational and planning purposes, water resource managers responsible for large regions need to estimate the spatial variability of resources over large areas, at a spatial resolution finer than can be provided by observed data alone. Second, hydrologists and water managers are interested in the effects of land-use and climate variability and change over a large geographic domain. Third, there is an increasing need of using hydrologic models as a base to estimate point and non-point sources of pollution loading to streams. Fourth, hydrologists and atmospheric modellers have perceived weaknesses in the representation of hydrological processes in regional and global climate models, and developed global hydrological models to overcome the weaknesses of global climate models. Considerable progress in the development and application of global hydrological models has been achieved to date, however, large uncertainties still exist considering the model structure including large scale flow routing, parameterization, input data, etc. This presentation will focus on the global hydrological models, and the discussion includes (1) types of global hydrological models, (2) procedure of global hydrological model development

  12. From Numeric Models to Granular System Modeling

    Directory of Open Access Journals (Sweden)

    Witold Pedrycz

    2015-03-01

    To make this study self-contained, we briefly recall the key concepts of granular computing and demonstrate how this conceptual framework and its algorithmic fundamentals give rise to granular models. We discuss several representative formal setups used in describing and processing information granules including fuzzy sets, rough sets, and interval calculus. Key architectures of models dwell upon relationships among information granules. We demonstrate how information granularity and its optimization can be regarded as an important design asset to be exploited in system modeling and giving rise to granular models. With this regard, an important category of rule-based models along with their granular enrichments is studied in detail.

  13. Environmental Satellite Models for a Macroeconomic Model

    International Nuclear Information System (INIS)

    To support national environmental policy, it is desirable to forecast and analyse environmental indicators consistently with economic variables. However, environmental indicators are physical measures linked to physical activities that are not specified in economic models. One way to deal with this is to develop environmental satellite models linked to economic models. The system of models presented gives a frame of reference where emissions of greenhouse gases, acid gases, and leaching of nutrients to the aquatic environment are analysed in line with - and consistently with - macroeconomic variables. This paper gives an overview of the data and the satellite models. Finally, the results of applying the model system to calculate the impacts on emissions and the economy are reviewed in a few illustrative examples. The models have been developed for Denmark; however, most of the environmental data used are from the CORINAIR system implemented in numerous countries

  14. Geologic Framework Model Analysis Model Report

    International Nuclear Information System (INIS)

    The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M and O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and

  15. Geologic Framework Model Analysis Model Report

    Energy Technology Data Exchange (ETDEWEB)

    R. Clayton

    2000-12-19

    The purpose of this report is to document the Geologic Framework Model (GFM), Version 3.1 (GFM3.1) with regard to data input, modeling methods, assumptions, uncertainties, limitations, and validation of the model results, qualification status of the model, and the differences between Version 3.1 and previous versions. The GFM represents a three-dimensional interpretation of the stratigraphy and structural features of the location of the potential Yucca Mountain radioactive waste repository. The GFM encompasses an area of 65 square miles (170 square kilometers) and a volume of 185 cubic miles (771 cubic kilometers). The boundaries of the GFM were chosen to encompass the most widely distributed set of exploratory boreholes (the Water Table or WT series) and to provide a geologic framework over the area of interest for hydrologic flow and radionuclide transport modeling through the unsaturated zone (UZ). The depth of the model is constrained by the inferred depth of the Tertiary-Paleozoic unconformity. The GFM was constructed from geologic map and borehole data. Additional information from measured stratigraphy sections, gravity profiles, and seismic profiles was also considered. This interim change notice (ICN) was prepared in accordance with the Technical Work Plan for the Integrated Site Model Process Model Report Revision 01 (CRWMS M&O 2000). The constraints, caveats, and limitations associated with this model are discussed in the appropriate text sections that follow. The GFM is one component of the Integrated Site Model (ISM) (Figure l), which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed project stratigraphy into model stratigraphic units that are most useful for the primary downstream models and the

  16. Model Theory and Applications

    CERN Document Server

    Mangani, P

    2011-01-01

    This title includes: Lectures - G.E. Sacks - Model theory and applications, and H.J. Keisler - Constructions in model theory; and, Seminars - M. Servi - SH formulas and generalized exponential, and J.A. Makowski - Topological model theory.

  17. Wildfire Risk Main Model

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The model combines three modeled fire behavior parameters (rate of spread, flame length, crown fire potential) and one modeled ecological health measure (fire...

  18. Collaborative networks: Reference modeling

    NARCIS (Netherlands)

    L.M. Camarinha-Matos; H. Afsarmanesh

    2008-01-01

    Collaborative Networks: Reference Modeling works to establish a theoretical foundation for Collaborative Networks. Particular emphasis is put on modeling multiple facets of collaborative networks and establishing a comprehensive modeling framework that captures and structures diverse perspectives of

  19. Computational neurogenetic modeling

    CERN Document Server

    Benuskova, Lubica

    2010-01-01

    Computational Neurogenetic Modeling is a student text, introducing the scope and problems of a new scientific discipline - Computational Neurogenetic Modeling (CNGM). CNGM is concerned with the study and development of dynamic neuronal models for modeling brain functions with respect to genes and dynamic interactions between genes. These include neural network models and their integration with gene network models. This new area brings together knowledge from various scientific disciplines, such as computer and information science, neuroscience and cognitive science, genetics and molecular biol

  20. TRACKING CLIMATE MODELS

    Data.gov (United States)

    National Aeronautics and Space Administration — CLAIRE MONTELEONI*, GAVIN SCHMIDT, AND SHAILESH SAROHA* Climate models are complex mathematical models designed by meteorologists, geophysicists, and climate...