578 research outputs found
Sero-prevalence of Taenia spp. infections in Cattle and Pigs in Rural Farming Communities in Free State and Gauteng Provinces, South Africa
Energy Dissipation and Regularity for a Coupled Navier-Stokes and Q-Tensor System
We study a complex non-newtonian fluid that models the flow of nematic liquid
crystals. The fluid is described by a system that couples a forced
Navier-Stokes system with a parabolic-type system. We prove the existence of
global weak solutions in dimensions two and three. We show the existence of a
Lyapunov functional for the smooth solutions of the coupled system and use the
cancellations that allow its existence to prove higher global regularity, in
dimension two. We also show the weak-strong uniqueness in dimension two
Coverage of the 2011 Q fever vaccination campaign in the Netherlands, using retrospective population-based prevalence estimation of cardiovascular risk-conditions for chronic Q fever
Background: In 2011, a unique Q fever vaccination campaign targeted people at risk for chronic Q fever in the southeast of the Netherlands. General practitioners referred patients with defined cardiovascular risk-conditions (age >15 years). Prevalence rates of those risk-conditions were lacking, standing in the way of adequate planning and coverage estimation. We aimed to obtain prevalence rates retrospectively in order to estimate coverage of the Q fever vaccination campaign. Methods: With broad search terms for these predefined risk-conditions, we extracted patient-records from a large longitudinal general-practice research-database in the Netherlands (IPCI-database). Afte
Coverage of the 2011 Q fever vaccination campaign in the Netherlands, using retrospective population-based prevalence estimation of cardiovascular risk-conditions for chronic Q fever
Background: In 2011, a unique Q fever vaccination campaign targeted people at risk for chronic Q fever in the southeast of the Netherlands. General practitioners referred patients with defined cardiovascular risk-conditions (age >15 years). Prevalence rates of those risk-conditions were lacking, standing in the way of adequate planning and coverage estimation. We aimed to obtain prevalence rates retrospectively in order to estimate coverage of the Q fever vaccination campaign. Methods: With broad search terms for these predefined risk-conditions, we extracted patient-records from a large longitudinal general-practice research-database in the Netherlands (IPCI-database). Afte
Association between vaccine adjuvant effect and pre-seasonal immunity. Systematic review and meta-analysis of randomised immunogenicity trials comparing squalene-adjuvanted and aqueous inactivated influenza vaccines
The immunogenicity benefit of inactivated influenza vaccine (IIV) adjuvanted by squalene over non-adjuvanted aqueous IIV was explored in a meta-analysis involving 49 randomised trials published between 1999 and 2017, and 22,470 eligible persons of all age classes. Most vaccines contained 15 μg viral haemagglutinin per strain. Adjuvanted IIV mostly contained 9.75 mg squalene per dose. Homologous pre- and post-vaccination geometric mean titres (GMTs) of haemagglutination-inhibition (HI) antibody were recorded for 290 single influenza (sub-)type arms. The adjuvant effect was expressed as the ratio of post-vaccination GMTs between squalene-IIV and aqueous IIV (GMTR, 145 estimates). GMTRs > 1.0 favoured squalene-IIV over aqueous IIV. For all influenza (sub-)types, the adjuvant effect proved negatively associated with pre-vaccination GMT and mean age. The adjuvant effect appeared most pronounced in young children (mean age < 2.5 years) showing an average GMTR of 3.7 (95% CI: 2.5 to 5.5). With increasing age, GMTR values gradually decreased towards 1.4 (95% CI: 1.0 to 1.9) in older adults. Heterologous antibody titrations simulating mismatch between vaccine and circulating virus (30 GMTR estimates) again showed a larger adjuvant effect at young age. GMT values and their variances were converted to antibody-predicted protection rates using an evidence-based clinical protection curve. The adjuvant effect was expressed as the protection rate differences, which showed similar age patterns as corresponding GMTR values. However for influenza B, the adjuvant effect lasted longer than for influenza A, possibly due to a generally later influenza B virus exposure. Collectively, this meta-analysis indicates the highest benefit of squalene-IIV over aqueous IIV in young children and decreasing benefit with progressing age. This trend is similar for seasonal influenza (sub-)types and the 2009 pandemic strain, by both homologous and heterologous titration. The impact of pre-seasonal immunity on vaccine effectiveness, and its implications for age-specific vaccination recommendations, are discussed
An Infrared Divergence Problem in the cosmological measure theory and the anthropic reasoning
An anthropic principle has made it possible to answer the difficult question
of why the observable value of cosmological constant (
GeV) is so disconcertingly tiny compared to predicted value of vacuum
energy density GeV. Unfortunately, there is a
darker side to this argument, as it consequently leads to another absurd
prediction: that the probability to observe the value for randomly
selected observer exactly equals to 1. We'll call this controversy an infrared
divergence problem. It is shown that the IRD prediction can be avoided with the
help of a Linde-Vanchurin {\em singular runaway measure} coupled with the
calculation of relative Bayesian probabilities by the means of the {\em
doomsday argument}. Moreover, it is shown that while the IRD problem occurs for
the {\em prediction stage} of value of , it disappears at the {\em
explanatory stage} when has already been measured by the observer.Comment: 9 pages, RevTe
A regionally informed abundance index for supporting integrative analyses across butterfly monitoring schemes
1. The rapid expansion of systematic monitoring schemes necessitates robust methods to reliably assess species' status and trends. Insect monitoring poses a challenge where there are strong seasonal patterns, requiring repeated counts to reliably assess abundance. Butterfly monitoring schemes (BMSs) operate in an increasing number of countries with broadly the same methodology, yet they differ in their observation frequency and in the methods used to compute annual abundance indices.
2. Using simulated and observed data, we performed an extensive comparison of two approaches used to derive abundance indices from count data collected via BMS, under a range of sampling frequencies. Linear interpolation is most commonly used to estimate abundance indices from seasonal count series. A second method, hereafter the regional generalized additive model (GAM), fits a GAM to repeated counts within sites across a climatic region. For the two methods, we estimated bias in abundance indices and the statistical power for detecting trends, given different proportions of missing counts. We also compared the accuracy of trend estimates using systematically degraded observed counts of the Gatekeeper Pyronia tithonus (Linnaeus 1767).
3. The regional GAM method generally outperforms the linear interpolation method. When the proportion of missing counts increased beyond 50%, indices derived via the linear interpolation method showed substantially higher estimation error as well as clear biases, in comparison to the regional GAM method. The regional GAM method also showed higher power to detect trends when the proportion of missing counts was substantial.
4. Synthesis and applications. Monitoring offers invaluable data to support conservation policy and management, but requires robust analysis approaches and guidance for new and expanding schemes. Based on our findings, we recommend the regional generalized additive model approach when conducting integrative analyses across schemes, or when analysing scheme data with reduced sampling efforts. This method enables existing schemes to be expanded or new schemes to be developed with reduced within-year sampling frequency, as well as affording options to adapt protocols to more efficiently assess species status and trends across large geographical scales
PRIMJENA LINEARNOG PROGRAMIRANJA NA DRUŠTVENIM POLJOPRIVREDNIM GOSPODARSTVIMA
In recent years there has been significant interest in modelling cumulative effects and the population consequences of individual changes in cetacean behaviour and physiology due to disturbance. One potential source of disturbance that has garnered particular interest is whale-watching. Though perceived as 'green' or eco-friendly tourism, there is evidence that whale-watching can result in statistically significant and biologically meaningful changes in cetacean behaviour, raising the question whether whale-watching is in fact a long term sustainable activity. However, an assessment of the impacts of whale-watching on cetaceans requires an understanding of the potential behavioural and physiological effects, data to effectively address the question and suitable modelling techniques. Here, we review the current state of knowledge on the viability of long-term whale-watching, as well as logistical limitations and potential opportunities. We conclude that an integrated, coordinated approach will be needed to further understanding of the possible effects of whale-watching on cetaceans.Publisher PDFPeer reviewe
Branching Fractions for D0 -> K+K- and D0 -> pi+pi-, and a Search for CP Violation in D0 Decays
Using the large hadroproduced charm sample collected in experiment E791 at
Fermilab, we have measured ratios of branching fractions for the two-body
singly-Cabibbo-suppressed charged decays of the D0:
(D0 -> KK)/(D0 -> Kpi) = 0.109 +- 0.003 +- 0.003,
(D0 -> pipi)/(D0 -> Kpi) = 0.040 +- 0.002 +- 0.003, and
(D0 -> KK)/(D0 -> pipi) = 2.75 +- 0.15 +- 0.16. We have looked for
differences in the decay rates of D0 and D0bar to the CP eigenstates K+K- and
pi+pi-, and have measured the CP asymmetry parameters
A_CP(K+K-) = -0.010 +- 0.049 +- 0.012 and
A_CP(pi+pi-) = -0.049 +- 0.078 +- 0.030, both consistent with zero.Comment: 10 Postscript pages, including 2 figures. Submitted to Phys. Lett.
An ALMA Survey of the SCUBA-2 Cosmology Legacy Survey UKIDSS/UDS Field: The Far-infrared/Radio Correlation for High-redshift Dusty Star-forming Galaxies
We study the radio properties of 706 submillimeter galaxies (SMGs) selected at 870 μm with the Atacama Large Millimeter Array from the SCUBA-2 Cosmology Legacy Survey map of the Ultra Deep Survey field. We detect 273 SMGs at >4σ in deep Karl G. Jansky Very Large Array 1.4 GHz observations, of which a subset of 45 SMGs are additionally detected in 610 MHz Giant Metre-Wave Radio Telescope imaging. We quantify the far-infrared/radio correlation (FIRRC) through parameter q IR, defined as the logarithmic ratio of the far-infrared and radio luminosity, and include the radio-undetected SMGs through a stacking analysis. We determine a median q IR = 2.20 ± 0.03 for the full sample, independent of redshift, which places these z ~ 2.5 dusty star-forming galaxies 0.44 ± 0.04 dex below the local correlation for both normal star-forming galaxies and local ultra-luminous infrared galaxies (ULIRGs). Both the lack of redshift evolution and the offset from the local correlation are likely the result of the different physical conditions in high-redshift starburst galaxies, compared to local star-forming sources. We explain the offset through a combination of strong magnetic fields (B gsim 0.2 mG), high interstellar medium (ISM) densities and additional radio emission generated by secondary cosmic rays. While local ULIRGs are likely to have similar magnetic field strengths, we find that their compactness, in combination with a higher ISM density compared to SMGs, naturally explains why local and high-redshift dusty star-forming galaxies follow a different FIRRC. Overall, our findings paint SMGs as a homogeneous population of galaxies, as illustrated by their tight and nonevolving far-infrared/radio correlation
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