818 research outputs found
Imported and travelling dogs as carriers of canine vector-borne pathogens in Germany
<p>Abstract</p> <p>Background</p> <p>With the import of pets and pets taken abroad, arthropod-borne diseases have increased in frequency in German veterinary practices. This is reflected by 4,681 dogs that have been either travelled to or relocated from endemic areas to Germany. The case history of these dogs and the laboratory findings have been compared with samples collected from 331 dogs living in an endemic area in Portugal. The various pathogens and the seroprevalences were examined to determine the occurrence of, and thus infection risk, for vector-borne pathogens in popular travel destinations.</p> <p>Results</p> <p>4,681 dogs were examined serological for <it>Leishmania infantum, Babesia canis </it>and <it>Ehrlichia canis</it>. Buffy coats were detected for <it>Hepatozoon canis </it>and blood samples were examined for microfilariae via the Knott's test. The samples were sent in from animal welfare organizations or private persons via veterinary clinics. Upon individual requests, dogs were additionally examined serological for <it>Anaplasma phagocytophilum, Borrelia burgdorferi </it>and <it>Rickettsia conorii</it>. Overall <it>B. canis </it>was the most prevalent pathogen detected by antibody titers (23.4%), followed by <it>L. infantum </it>(12.2%) and <it>E. canis </it>(10.1%). Microfilariae were detected in 7.7% and <it>H. canis </it>in 2.7% of the examined dogs. In 332/1862 dogs <it>A. phagocytophilum</it>, in 64/212 <it>B. burgdorferi </it>and in 20/58 <it>R. conorii </it>was detected. Of the 4,681 dogs, in total 4,226 were imported to Germany from endemic areas. Eighty seven dogs joined their owners for a vacation abroad. In comparison to the laboratory data from Germany, we examined 331 dogs from Portugal. The prevalence of antibodies/pathogens we detected was: 62.8% to <it>R. conorii</it>, 58% to <it>B. canis</it>, 30.5% to <it>A. phagocytophilum</it>, 24.8% to <it>E. canis</it>, 21.1% to <it>H. canis </it>(via PCR), 9.1% to <it>L. infantum </it>and 5.3% to microfilariae.</p> <p>Conclusions</p> <p>The examination of 4,681 dogs living in Germany showed pathogens like <it>L. infantum </it>that are non-endemic in Germany. Furthermore, the German data are similar in terms of multiple pathogen infection to the data recorded for dogs from Portugal. Based on these findings the importation of dogs from endemic predominantly Mediterranean regions to Germany as well as travelling with dogs to these regions carries a significant risk of acquiring an infection. Thus we would conclude that pet owners seek advice of the veterinarians prior to importing a dog from an endemic area or travel to such areas. In general, it might be advisable to have a European recording system for translocation of dogs.</p
Light controls motility and phase separation of photosynthetic microbes
Large ensembles of interacting, out-of-equilibrium agents are a paradigm of active matter. Their constituents' intrinsic activity may entail the spontaneous separation into localized phases of high and low densities. Motile microbes, equipped with ATP-fueled engines, are prime examples of such phase-separating active matter, which is fundamental in myriad biological processes. The fact that spontaneous spatial aggregation is not widely recognized as a general feature of microbial communities challenges the generalisation of phase separation beyond artificial active systems. Here, we report on the phase separation of populations of Chlamydomonas reinhardtii that can be controlled by light in a fully reversible manner. We trace this phenomenon back to the light- and density-dependent motility, thus bridging the gap from light perception on the single-cell level to collective spatial self-organization into regions of high and low density. Its spectral sensitivity suggests that microbial motility and phase separation are regulated by the activity of the photosynthetic machinery. Characteristic fingerprints of the stability and dynamics of this active system paint a picture that cannot be reconciled with the current physical understanding of phase separation in artificial active matter, whereby collective behavior can emerge from inherent motility modulation in response to changing stimuli. Our results therefore point towards the existence of a broader class of self-organization phenomena in living systems
A measurement of cosmic ray deuterium from 0.5â2.9 GeV/nucleon
The rare isotopes ^(2)H and ^(3)He in cosmic rays are believed to originate mainly from the interaction of high energy protons and helium with the galactic interstellar medium. The unique propagation history of these rare isotopes provides important constraints on galactic cosmic ray source spectra and on models for their propagation within the Galaxy. Hydrogen and helium isotopes were measured with the balloon-borne experiment, IMAX, which flew from Lynn Lake, Manitoba in 1992. The energy spectrum of deuterium between 0.5 and 3.2 GeV/nucleon measured by the IMAX experiment as well as previously published results of ^(3)He from the same instrument will be compared with predictions of cosmic ray galactic propagation models. The observed composition of the light isotopes is found to be generally consistent with the predictions of the standard Leaky Box Model derived to fit observations of heavier nucle
OvogenÚse chez l'anguille (Anguilla anguilla L. ) : ultrastructure de l'ovaire à différents stades de développement et implication des lipoprotéines au cours de la vitellogenÚse
The Health Education Research Experience (HERE) program metadata dataset
Undergraduate subject pools are prevalent across disciplines in the United States. The Health Education Research Experience (HERE) Program was the first known course-based subject pool entirely managed and conducted online for online students enrolled in an introductory health education/health promotion course. The program was conducted within five semesters from Spring 2012 through Summer 2013. The HERE Program encompassed 13 studies embedded in two sections of an undergraduate online course at the University of Florida. The studies were all related to course topics and current research topics in health education/promotion (as identified through the Healthy People 2020 Framework). The topics ranged from the relatively less sensitive health aspects of college life (i.e., technology use) to studies assessing more sensitive health topics (i.e., intimate partner violence and sexual assault). In alignment with a best practice in survey design, the HERE Program's survey instruments included one metadata item embedded in each survey to identify which devices students used to complete the surveys. Understanding which devices students used for survey completion has ramifications for survey designers and survey researchers. In contrast to the relative uniformity of pen and paper surveys and control of the survey completion environment, online surveys may not look identical across personal devices and may be completed in increasingly varied environments. All studies, study procedures and protocols, and metadata collection procedures were approved by the university's Institutional Review Board. The data presented here were extracted from each survey's data files and aggregated. The aggregated metadata are available through Mendeley Data in a.csv file for widespread access. Descriptive statistics are presented in tables. The data provided in this article will benefit researchers interested in survey methodology, questionnaire design, modes of survey collection, and survey metadata. The data are hosted in the following Mendeley Data repository: https://data.mendeley.com/datasets/ht9jmd3cdt/2
A reassessment of the Lochkovian, Lower Devonian, benthic faunas and palynomorphs from the Dornes region, southern Central Iberian Zone, Portugal
A revision of benthic faunas and palynomorphs previously described from the Dornes syncline, southern Central Iberian Zone,
Portugal, complemented with recent research, shows that the Serra de Luação Formation is of Lochkovian age. The systematics of
the benthic faunas, with clear Gondwana affinities, are described in detail
Cosmic antiprotons as a probe for supersymmetric dark matter?
The flux of cosmic ray antiprotons from neutralino annihilations in the
galactic halo is computed for a large sample of models in the MSSM (the Minimal
Supersymmetric extension of the Standard Model). We also revisit the problem of
estimating the background of low-energy cosmic ray induced secondary
antiprotons, taking into account their subsequent interactions (and energy
loss) and the presence of nuclei in the interstellar matter.
We consider a two-zone diffusion model, with and without a galactic wind. We
find that, given the uncertainties in the background predictions, there is no
need for a primary (exotic) component to explain present data. However,
allowing for a signal by playing with the uncertainties in the background
estimate, we discuss the characteristic features of the supersymmetric models
which give a satisfactory description of the data. We point out that in some
cases the optimal kinetic energy to search for a signal from supersymmetric
dark matter is above several GeV, rather than the traditional sub-GeV region.
The large astrophysical uncertainties involved do not, one the other hand,
allow the exclusion of any of the MSSM models we consider, on the basis of
data.
We present besides numerical results also convenient parameterizations of the
antiproton yields of all `basic' two-body final states. We also give examples
of the yield and differential energy spectrum for a set of supersymmetric
models with high rates.
We also remark that it is difficult to put a limit on the antiproton lifetime
from present measurements, since the injection of antiprotons from neutralino
annihilation can compensate the loss from decay.Comment: 22 pages, 11 figures, uses emulateapj.st
An enhanced CRISPR repressor for targeted mammalian gene regulation.
The RNA-guided endonuclease Cas9 can be converted into a programmable transcriptional repressor, but inefficiencies in target-gene silencing have limited its utility. Here we describe an improved Cas9 repressor based on the C-terminal fusion of a rationally designed bipartite repressor domain, KRAB-MeCP2, to nuclease-dead Cas9. We demonstrate the system's superiority in silencing coding and noncoding genes, simultaneously repressing a series of target genes, improving the results of single and dual guide RNA library screens, and enabling new architectures of synthetic genetic circuits
Palaeoenvironmental research at HaweltiâMelazo (Tigray, northern Ethiopia) â insights from sedimentological and geomorphological analyses
The sites of HaweltiâMelazo in the Tigray region of the northern Ethiopian Highlands is an archaeological hotspot related to the D'mt kingdom
(ca. 800â400âBCE). The existence of several monumental buildings, which
have been excavated since the 1950s, underline the importance of this area in the Ethio-Sabaean period. We investigated the geomorphological and
geological characteristics of the site and its surroundings and carried out
sedimentological analyses, as well as direct (luminescence) and indirect
(radiocarbon) sediment dating, to reconstruct the palaeoenvironmental
conditions, which we integrated into the wider context of Tigray.
Luminescence dating of feldspar grains from the May Agazin catchment
indicate enhanced fluvial activity in the late Pleistocene, likely connected to the re-occurring monsoon after the Last Glacial Maximum (LGM). The abundance of trap basalt on the Melazo plateau, which provides the basis for the development of fertile soils, and the presumably higher groundwater level during the Ethio-Sabaean Period, provided favourable settlement conditions. The peninsula-like shape of the Melazo plateau was easily accessible only from the east and northeast, while relatively steep scarps enclose the other edges of the plateau. This adds a possible natural protective function to this site.</p
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