Plasmonic Structure Integrated Single-Photon Detector Configurations to Improve Absorptance and Polarization Contrast

Configurations capable of maximizing both the absorption component of system detection efficiency and the achievable polarization contrast were determined for 1550 nm polarized light illumination of different plasmonic structure integrated superconducting nanowire single-photon detectors (SNSPDs) consisting of p = 264 nm and P = 792 nm periodic niobium nitride (NbN) patterns on silica substrate. Global effective NbN absorptance maxima appear in case of p/s-polarized light illumination in S/P-orientation (γ = 90°/0° azimuthal angle) and the highest polarization contrast is attained in S-orientation of all devices. Common nanophotonical origin of absorptance enhancement is collective resonance on nanocavity gratings with different profiles, which is promoted by coupling between localized modes in quarter-wavelength metal-insulator-metal nanocavities and laterally synchronized Brewster-Zenneck-type surface waves in integrated SNSPDs possessing a three-quarter-wavelength-scaled periodicity. The spectral sensitivity and dispersion characteristics reveal that device design specific optimal configurations exist

Analysis of a novel RNA virus in a wild northern white-breasted hedgehog (Erinaceus roumanicus)

Tombusviruses are generally considered plant viruses. A novel tombus-/carmotetravirus-like RNA virus was identified in a faecal sample and blood and muscle tissues from a wild northern white-breasted hedgehog (Erinaceus roumanicus). The complete genome of the virus, called H14-hedgehog/2015/HUN (GenBank accession number MN044446), is 4,118 nucleotides in length with a readthrough stop codon of type/group 1 in ORF1 and lacks a poly(A) tract at the 3' end. The predicted ORF1-RT (RdRp) and the capsid proteins had low (31-33%) amino acid sequence identity to unclassified tombus-/noda-like viruses (Hubei tombus-like virus 12 and Beihai noda-like virus 10), respectively, discovered recently in invertebrate animals. An in vivo experimental plant inoculation study showed that an in vitro-transcribed H14-hedgehog/2015/HUN viral RNA did not replicate in Nicotiana benthamiana, Chenopodium quinoa, or Chenopodium murale, the most susceptible hosts for plant-origin tombusviruses

Eco-epidemiology of Borrelia miyamotoi and Lyme borreliosis spirochetes in a popular hunting and recreational forest area in Hungary

BACKGROUND: Borrelia miyamotoi, the newly discovered human pathogenic relapsing fever spirochete, and Borrelia burgdorferi sensu lato are maintained in natural rodent populations. The aim of this study was to investigate the natural cycle of B. miyamotoi and B. burgdorferi s.l. in a forest habitat with intensive hunting, forestry work and recreational activity in Southern Hungary. METHODS: We collected rodents with modified Sherman-traps during 2010–2013 and questing ticks with flagging in 2012. Small mammals were euthanized, tissue samples were collected and all ectoparasites were removed and stored. Samples were screened for pathogens with multiplex quantitative real-time polymerase chain reaction (qPCR) targeting a part of flagellin gene, then analysed with conventional PCRs and sequencing. RESULTS: 177 spleen and 348 skin samples of six rodent species were individually analysed. Prevalence in rodent tissue samples was 0.2 % (skin) and 0.5 % (spleen) for B. miyamotoi and 6.6 % (skin) and 2.2 % (spleen) for B. burgdorferi s.l. Relapsing fever spirochetes were detected in Apodemus flavicollis males, B. burgdorferi s.l. in Apodemus spp. and Myodes glareolus samples. Borrelia miyamotoi was detected in one questing Ixodes ricinus nymph and B. burgdorferi s.l in nymphs and adults. In the ticks removed from rodents DNA amplification of both pathogens was successful from I. ricinus larvae (B. miyamotoi 5.6 %, B. burgdorferi s.l. 11.1 %) and one out of five nymphs while from Ixodes acuminatus larvae, and nymph only B. burgdorferi s.l. DNA was amplified. Sequencing revealed B. lusitaniae in a questing I. ricinus nymph and altogether 17 B. afzelii were identified in other samples. Two Dermacentor marginatus engorged larva pools originating from uninfected hosts were also infected with B. afzelii. CONCLUSIONS: This is the first report of B. miyamotoi occurrence in a natural population of A. flavicollis as well as in Hungary. We provide new data about circulation of B. burgdorferi s.l. in rodent and tick communities including the role of I. acuminatus ticks in the endophilic pathogen cycle. Our results highlight the possible risk of infection with relapsing fever and Lyme borreliosis spirochetes in forest habitats especially in the high-risk groups of hunters, forestry workers and hikers

Borrelia miyamotoi: egy újabb, humán patogén, kullancs által terjesztett, visszatérő lázat okozó baktérium | Borrelia miyamotoi: a recently identified human pathogenic tick-borne relapsing fever spirochete

Absztrakt: A Borrelia miyamotoi-t 1995-ben fedezték fel. Ez egy, emberben visszatérő lázat (relapsing fever, febris recurrens) okozó baktérium, amelyet az Ixodes ricinus fajcsoportba tartozó kullancsok terjesztenek. Ez a kórokozó genetikailag, járványtanilag és az általa okozott kórkép tekintetében is különbözik a szintén kullancsok által terjesztett Borrelia burgdorferi sensu lato (Lyme spirochaeta) baktériumoktól. Eddig világszerte több mint 50 heveny lázas megbetegedésben szenvedő páciensből mutatták már ki, ezenfelül három tumoros betegben meningoencephalitist okozott ez a kórokozó. A különböző élőhelyeken található kullancsok és gazdáik fertőzöttségének mértéke, eloszlása és a fertőzés mechanizmusa nem tisztázott még. A B. miyamotoi elsősorban lázat okoz, ami miatt más, kullancsok által terjesztett fertőzésekkel is összetéveszthető. Az utóbbi évek intenzív vizsgálatai alapján nemcsak egyre több földrajzi régióból mutatják ki ezt a baktériumot kullancsokból, de folyamatosan növekszik a publikált humán esetszám is, ezért növekvő jelentőségű (emerging) kórokozóként tartják számon. Irodalmi áttekintésünkben összegezzük az eddigi ismereteinket a Borrelia miyamotoi-val kapcsolatban. Orv Hetil. 2017; 158(29): 1124–1130. | Abstract: Borrelia miyamotoi is a recently described relapsing fever spirochete transmitted by ticks of the Ixodes ricinus complex. This pathogen is different from Borrelia burgdorferi sensu lato (the Lyme borreliosis spirochetes) in its epidemiology, ecology and also genetics. Over 50 patients have been described worldwide with Borrelia miyamotoi disease, and three immunocompromised patients were reported with neurological symptoms. Our knowledge about Borrelia miyamotoi infection in ticks and its distribution in different habitats and also the mechanism of the infection is limited. The most common symptom is fever; thus it can be easily confused with other tick-borne diseases. Due to the intensive research in recent years, Borrelia miyamotoi infection in ticks and hosts has been reported from different regions and also the number of patients is increasing, thus this bacterium is considered as an emerging pathogen. In this literature review we would like to summarize the available knowledge about this spirochete. Orv Hetil. 2017, 158(29): 1124–1130