scholarly journals Cyclic patterns in the central European tick-borne encephalitis incidence series

2016 ◽  
Vol 145 (2) ◽  
pp. 358-367 ◽  
Author(s):  
P. ZEMAN
Keyword(s):  
External Factors ◽  
Disease Dynamics ◽  
Large Area ◽  
Climatic Forcing ◽  
Human Contact ◽  
Cyclic Patterns ◽  
Tick Borne Encephalitis ◽  
Synchronization Signal ◽  
Phase Variations ◽  
High Degree

SUMMARYTick-borne encephalitis (TBE) is peculiar due to its unstable dynamics with profound inter-annual fluctuations in case numbers – a phenomenon not well understood to date. Possible reasons – apart from variable human contact with TBE foci – include external factors, e.g. climatic forcing, autonomous oscillations of the disease system itself, or a combined action of both. Spectral analysis of TBE data from six regions of central Europe (CE) revealed that the ostensibly chaotic dynamics can be explained in terms of four superposed (quasi-)periodical oscillations: a quasi-biennial, triennial, pentennial, and a decadal cycle. These oscillations exhibit a high degree of regularity and synchrony across CE. Nevertheless, some amplitude and phase variations are responsible for regional differences in incidence patterns. In addition, periodic changes occur in the degree of synchrony in the regions: marked in-phase periods alternate with rather off-phase periods. Such a feature in the disease dynamics implies that it arises as basically diverging self-oscillations of local disease systems which, at intervals, receive synchronizing impulses, such as periodic variations in food availability for key hosts driven by external factors. This makes the disease dynamics synchronized over a large area during peaks in the synchronization signal, shifting to asynchrony in the time in between.

scholarly journals Identification of effective spreaders in contact networks using dynamical influence

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Ruaridh A. Clark ◽  
Malcolm Macdonald
Keyword(s):  
Disease Transmission ◽  
Average Rate ◽  
Laplacian Matrix ◽  
Disease Spread ◽  
Eigenvector Centrality ◽  
Contact Networks ◽  
Human Contact ◽  
Spread Dynamics ◽  
Definition Of ◽  
High Degree

AbstractContact networks provide insights on disease spread due to the duration of close proximity interactions. For systems governed by consensus dynamics, network structure is key to optimising the spread of information. For disease spread over contact networks, the structure would be expected to be similarly influential. However, metrics that are essentially agnostic to the network’s structure, such as weighted degree (strength) centrality and its variants, perform near-optimally in selecting effective spreaders. These degree-based metrics outperform eigenvector centrality, despite disease spread over a network being a random walk process. This paper improves eigenvector-based spreader selection by introducing the non-linear relationship between contact time and the probability of disease transmission into the assessment of network dynamics. This approximation of disease spread dynamics is achieved by altering the Laplacian matrix, which in turn highlights why nodes with a high degree are such influential disease spreaders. From this approach, a trichotomy emerges on the definition of an effective spreader where, for susceptible-infected simulations, eigenvector-based selections can either optimise the initial rate of infection, the average rate of infection, or produce the fastest time to full infection of the network. Simulated and real-world human contact networks are examined, with insights also drawn on the effective adaptation of ant colony contact networks to reduce pathogen spread and protect the queen ant.

scholarly journals Two-dimensional nanoframes with dual rims

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Sungjae Yoo ◽  
Jeongwon Kim ◽  
Sungwoo Choi ◽  
Doojae Park ◽  
Sungho Park
Keyword(s):  
Van Der Waals ◽  
Selective Etching ◽  
Van Der Waals Interactions ◽  
Two Dimensional ◽  
Large Area ◽  
Lattice Constants ◽  
Size And Shape ◽  
Single Entity ◽  
Synthetic Strategy ◽  
High Degree

AbstractThe synthesis of highly complex two-dimensional (2D) metal nanoframes remains a great challenge. Synthetic strategies for preparing 2D metal nanoframes are few, and rational and systematic synthetic pathways to more complicated architectures have not yet been reported. Herein, we demonstrate a stepwise synthetic strategy for complex 2D metal nanoframes with a high degree of intricacy; the strategy leads to a variety of shapes, including rings, triangles, hexagons, and tripods with tailorable single or double frames in a single entity. These nanoframes of high homogeneity could be obtained through selective combination of four different chemical toolkits consisting of selective etching and deposition on certain facets, and concentric and/or eccentric regrowth by controlling the mismatches of lattice constants of metals. The resulting nanoframes were highly homogeneous in size and shape and had van der Waals interactions that maximized rim-to-rim contact, allowing them to uniquely self-assemble into large-area superstructures.

Internal-External Control and Causal Attributions of Own and Others' Performance

1975 ◽  
Vol 37 (2) ◽  
pp. 423-426 ◽  
Author(s):  
Donn L. Kaiser
Keyword(s):  
Factorial Design ◽  
Internal Control ◽  
Causal Attributions ◽  
External Factors ◽  
External Control ◽  
Internal Factors ◽  
Low Degree ◽  
High Degree

In a 3 × 3 factorial design, 69 subjects with a high, medium, or low perceived internal control on Rotter's I-E scale judged the degree to which they thought three grades on a classroom examination resulted from effort and ability (internal factors) as opposed to type of test and luck (external factors). The three grades were the subject's own grade, the highest grade in class, and the lowest grade in class. Results showed that subjects with a high degree of internal control on the I-E scale attributed all three grades to internal factors significantly more than subjects with a low degree of internal control. Internal attributions were significantly higher for the highest grade in class than for the others.

scholarly journals The Concept of Steady State, Cyclicity and Debris Unloading of Debris-Covered Glaciers

2021 ◽  
Vol 9 ◽  
Author(s):  
Christoph Mayer ◽  
Carlo Licciulli
Keyword(s):  
Steady State ◽  
Coupled System ◽  
Glacier Mass Balance ◽  
Climatic Forcing ◽  
Ice Dynamics ◽  
Glacier Tongue ◽  
Debris Removal ◽  
Different Response ◽  
Glacier Advance ◽  
High Degree

It can easily be expected that debris-covered glaciers show a different response on external forcing compared to clean-surface glaciers. The supra-glacial debris cover acts as an additional transfer layer for the energy exchange between atmosphere and ice. The related glacier reaction is the integral of local effects, which changes strongly between enhanced melt for thin debris layers and considerably reduced melt for thicker debris. Therefore, a realistic feedback study can only be performed, if both the ice flow and the debris-influenced melt is treated with a high degree of detail. We couple a full Stokes representation of ice dynamics and the most complete description of energy transfer through the debris layer, in order to describe the long-term glacier reaction in the coupled system. With this setup, we can show that steady-state conditions are highly unlikely for glaciers, in case debris is not unloaded from the surface. For continuous and complete debris removal from the lowermost glacier tongue, however, a balance of the debris budget and the glacier conditions are possible. Depending on displacement and removal processes, our results demonstrate that debris-covered glaciers have an inherent tendency to switch to an oscillating state. Then, glacier mass balance and debris balance are out of phase, such that glacier advance periods end with the separation of the heavily debris-loaded lowermost glacier tongue, at time scales of decades to centuries. As these oscillations are inherent and happen without any variations in climatic forcing, it is difficult to interpret modern observations on the fluctuation of debris-covered glaciers on the basis of a changing climate only.

scholarly journals SENSE OF HUMOR MANIFESTATION: VERBAL AND PARAVERBAL MEANS

2017 ◽  
pp. 98-105
Author(s):  
Vladimir V. Naumov ◽  
Keyword(s):  
External Factors ◽  
Sense Of Humor ◽  
Linguistic Sign ◽  
Internal And External Factors ◽  
High Degree

The paper reports on the analysis of the evolution of verbal and paraverbal means of expressing the sense of humor. The results indicate that the absence of the sense of humor in medieval times can be explained by the symmetry of form and meaning of the linguistic sign and high degree of mentality stereotypization. The article views internal and external factors of the sense of humor emerging and its manifestation in different lingual cultures. It is shown that it has different gradations and forms. Paraverbal means of expressing the sense of humor in different lingual cultures are analyzed. It is stressed that social and ethnic rules of speech and paraverbal behavior prescribe certain reactions of the interlocutor.

scholarly journals Molecular Mimicry and Assemblies of Asymmetric Organic Semiconductors

2021 ◽  
Author(s):  
Craig Yu ◽  
Shohei Kumagai ◽  
Michitsuna Tsutsumi ◽  
Tadanori Kurosawa ◽  
Hiroyuki Ishii ◽  
...  
Keyword(s):  
Organic Semiconductors ◽  
Alkyl Chain ◽  
Molecular Mimicry ◽  
Design Feature ◽  
Molecular Assembly ◽  
Large Area ◽  
Alkyl Chains ◽  
Synthetic Strategy ◽  
Chain Lengths ◽  
High Degree

Abstract Molecular assembly is a crucial factor for charge transports in organic semiconductors (OSCs), and molecularly flexible alkyl chain substitution is a key design feature for achieving desired molecular assemblies. However, the high degree of freedom of alkyl chains leads to molecular fluctuations that are detrimental to OSC performances. Stabilization of alkyl chains via intermolecular interactions in packing structures exists in biological and materials systems, and such a strategy can be harnessed in OSCs to suppress molecular fluctuations. Here, we present a robust synthetic strategy for a series of asymmetric n-type benzo[de]isoquinolino[1,8-gh]quinolinetetracarboxylic diimide (BQQDI) OSCs with various alkyl chain lengths, and certain alkyl chains exhibit an unusual molecular mimicry with energetically favorable gauche conformer that shows isomorphic structures and small molecular fluctuations. Asymmetric n-type OSC with the optimum chain length exhibits satisfactory solubility, excellent electron mobility, and large-area single-crystalline thin films are fabricated for practical organic electronics.

scholarly journals Soil Reservoir Dynamics of Ophidiomyces ophidiicola, the Causative Agent of Snake Fungal Disease

2021 ◽  
Vol 7 (6) ◽  
pp. 461
Author(s):  
Lewis J. Campbell ◽  
Joanna Burger ◽  
Robert T. Zappalorti ◽  
John F. Bunnell ◽  
Megan E. Winzeler ◽  
...  
Keyword(s):  
Causative Agent ◽  
Fungal Disease ◽  
Soil Samples ◽  
Disease Dynamics ◽  
Wildlife Diseases ◽  
Sterile Soil ◽  
Detection Rates ◽  
Snake Fungal Disease ◽  
Wildlife Pathogens ◽  
High Degree

Wildlife diseases pose an ever-growing threat to global biodiversity. Understanding how wildlife pathogens are distributed in the environment and the ability of pathogens to form environmental reservoirs is critical to understanding and predicting disease dynamics within host populations. Snake fungal disease (SFD) is an emerging conservation threat to North American snake populations. The causative agent, Ophidiomyces ophidiicola (Oo), is detectable in environmentally derived soils. However, little is known about the distribution of Oo in the environment and the persistence and growth of Oo in soils. Here, we use quantitative PCR to detect Oo in soil samples collected from five snake dens. We compare the detection rates between soils collected from within underground snake hibernacula and associated, adjacent topsoil samples. Additionally, we used microcosm growth assays to assess the growth of Oo in soils and investigate whether the detection and growth of Oo are related to abiotic parameters and microbial communities of soil samples. We found that Oo is significantly more likely to be detected in hibernaculum soils compared to topsoils. We also found that Oo was capable of growth in sterile soil, but no growth occurred in soils with an active microbial community. A number of fungal genera were more abundant in soils that did not permit growth of Oo, versus those that did. Our results suggest that soils may display a high degree of both general and specific suppression of Oo in the environment. Harnessing environmental suppression presents opportunities to mitigate the impacts of SFD in wild snake populations.

scholarly journals High Crystalline Quality Conductive Polypyrrole Film Prepared by Interface Chemical Oxidation Polymerization Method

2021 ◽  
Vol 12 (1) ◽  
pp. 58
Author(s):  
Yuefei Wang ◽  
Renjing Song ◽  
Li Li ◽  
Rongpeng Fu ◽  
Zhiguo Liu ◽  
...  
Keyword(s):  
Chemical Oxidation ◽  
Crystalline Quality ◽  
Large Area ◽  
High Crystalline Quality ◽  
Xrd Diffraction ◽  
Chemical Oxidation Polymerization ◽  
Polypyrrole Film ◽  
High Degree ◽  
Polymerization Method ◽  
Degree Of Order

The authors report that polypyrrole (PPy) films with large area and high crystalline quality have been achieved using an interfacial chemical oxidation method. By dissolving different reactants in two immiscible solvents, the PPy is synthetized at the interface region of the two solutions. The PPy films have sharp XRD diffraction peaks, indicating that the molecular chains in the film are arranged in a high degree of order and that they reflect high crystalline quality. High crystal quality is also conducive to improving electrical conductivity. The conductivity of the as prepared PPy film is about 0.3 S/cm, and the carrier mobility is about 5 cm2/(Vs). In addition, the biggest advantage of this method is that the prepared PPy film has a large area and is easy to transfer to other substrates. This will confidently broaden the application of PPy in the future.

Synoptic view on sub-ionospheric VLF/LF amplitude and phase variations at the Graz seismo-electromagnetic facility

2021 ◽  
Author(s):  
Hans Eichelberger ◽  
Konrad Schwingenschuh ◽  
Mohammed Y. Boudjada ◽  
Bruno P. Besser ◽  
Daniel Wolbang ◽  
...  
Keyword(s):  
Seismic Events ◽  
Coupling Mechanism ◽  
Natural Disturbances ◽  
Seismic Zone ◽  
External Forcing ◽  
Physical Processes ◽  
Large Area ◽  
International Networks ◽  
Space Research Institute ◽  
Phase Variations

<p>This presentation discusses physical processes related to potentially seismic and non-seismic disturbances along VLF/LF paths measured with two different receivers located side by side at the Space Research Institute (IWF) facility in Graz, Austria. At the same time both systems are embedded in international networks which gives the unique opportunity to probe the waveguide cavity over a large area.<br>In general, a variety of VLF/LF amplitude and phase variations are ubiquitous at wide scales throughout the cavity. We analyse such signals observed in the period 2018-2020 (solar minimum, i.e. less external forcing of the upper ionospheric boundary) in the time- and frequency-domain for several paths. In this attempt we aim to single out natural disturbances, characterise the source event, and figure out the lithosphere-atmosphere-ionosphere coupling mechanism. For known seismic events we consider the so-called Dobrovolsky-Bowman relationship [1,2] allowing to estimate the pre-seismic zone crossed by the VLF/LF paths.<br>The findings open up good prospects for an automated monitoring and characterisation of source phenomena who affect the electric field of VLF/LF sub-ionospheric links.</p><p>Ref:<br>[1] Dobrovolsky, I.P., Zubkov, S.I., and Miachkin, V.I., Estimation of the size of earthquake preparation zones, PAGEOPH 117, 1025–1044, 1979.<br>https://doi.org/10.1007/BF00876083<br>[2] Bowman, D.D., Ouillon, G., Sammis, C.G., Sornette, A., and Sornette, D., An observational test of the critical earthquake concept, JGR Solid<br>Earth, 103, B10, 24359-24372, 1998. https://doi.org/10.1029/98JB00792</p>

scholarly journals ENDURING IMMUNITY FOLLOWING VACCINATION OF MICE WITH FORMALIN-INACTIVATED VIRUS OF RUSSIAN SPRING-SUMMER (FAR EASTERN, TICK-BORNE) ENCEPHALITIS

1945 ◽  
Vol 82 (6) ◽  
pp. 431-443 ◽  
Author(s):  
J. Casals ◽  
Peter K. Olitsky
Keyword(s):  
Immune Response ◽  
Neutralizing Antibody ◽  
Human Beings ◽  
Immune State ◽  
Active Virus ◽  
Long Period ◽  
Tick Borne Encephalitis ◽  
High Degree ◽  
Far Eastern ◽  
Circulating Antibody

A single course of two intraperitoneal injections of formalin-inactivated virus of Russian spring-summer encephalitis induced in albino mice a solidly immune state which endured almost throughout life. Active virus is therefore not essential for the production of a high degree of lasting immunity. The immune response to vaccination consists of resistance to peripherally introduced active virus and development of circulating antibody. A correlation has been found to exist throughout the long period of the immune state between the titer of neutralizing antibody, as determined by the intraperitoneal method described, and the degree of immunity to peripherally introduced active virus. Thus laboratory tests for the immunizing power of a vaccine suggest themselves, to be carried out by an estimation in vaccinated mice of (a) immunity to peripherally inoculated active virus, and (b) serum virus-neutralizing antibody determined by the intraperitoneal method. The rôles as indicators of immunity in vaccinated mice of complement-fixing antibody in the serum, of the intracerebral challenge dose of virus, and of the intracerebral method for testing neutralizing antibody are discussed. Finally, if the immune response of man to vaccination with formalin-inactivated virus of Russian spring-summer encephalitis follows the pattern of the response of mice as here described, and if the correlation of neutralizing antibody with immunity to peripherally introduced virus applies to man as to mice, then possibly the degree of immunity in human beings following vaccination can be appraised by a peripheral test for neutralizing antibody in the serum.

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