117 research outputs found
Working in virtual environments: Three practical collaborative web tools
In our work as researchers and development workers, we are tasked with producing more and more information, even though we complain about information overload. Collaboration is increasingly complex but is fundamental to achieving our goal of reducing poverty and hunger through high-quality international agricultural research, partnership and leadership. Recent developments in information and communications technology (ICT) can make data, information and knowledge more available, accessible and applicable (CGIAR ICT-KM Program, 2008), which should contribute significantly to the effectiveness of our collaborative work. This Brief describes three web tools that can enhance participation and collaboration in geographically distributed teams: wikis, blogs, and social bookmarking. Each tool is briefly explained, examples of use are provided and analyzed, and some useful practices are suggested. It is our assumption that by making it easy to produce and share information, we can empower our staff, engage more effectively with our partners, and reach a wider audience of end users
Quantum Hydrodynamic Model by Moment Closure of Wigner Equation
In this paper, we derive the quantum hydrodynamics models based on the moment
closure of the Wigner equation. The moment expansion adopted is of the Grad
type firstly proposed in \cite{Grad}. The Grad's moment method was originally
developed for the Boltzmann equation. In \cite{Fan_new}, a regularization
method for the Grad's moment system of the Boltzmann equation was proposed to
achieve the globally hyperbolicity so that the local well-posedness of the
moment system is attained. With the moment expansion of the Wigner function,
the drift term in the Wigner equation has exactly the same moment
representation as in the Boltzmann equation, thus the regularization in
\cite{Fan_new} applies. The moment expansion of the nonlocal Wigner potential
term in the Wigner equation is turned to be a linear source term, which can
only induce very mild growth of the solution. As the result, the local
well-posedness of the regularized moment system for the Wigner equation remains
as for the Boltzmann equation
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Tunnelivadelman kirvatorjunnan tehostaminen Anthocoris nemoralis -petoluteen avulla
Tunneli suojaa vadelmakasvustoa monilta kasvitaudeilta ja tuholaisilta, mutta tunneliin päästessään esimerkiksi kirvat lisääntyvät nopeasti, eivätkä biologiset torjuntaeliöt aina torju kirvoja riittävän tehokkaasti. Tunnelivadelmalla esiintyy isovattukirvaa sekä pikkuvattukirvaa. Kirvatorjun-nan tehostamiseen lähdettiin hakemaan apua kenttäkokeella, jossa kirvatorjuntaan käytettiin tyrninokkaludetta (Anthocoris nemoralis). Toimeksiantajana opinnäytetyössä oli biologinen torjuntafirma Biotus Oy.
Koe suoritettiin uusimaalaisella tilalla kahdessa vadelmatunnelissa kesän 2017 aikana. Tunneleihin levitettiin kolmen viikon välein hyötyeliöitä. Hyötyeliöinä kokeessa käytettiin vainokaisia, kirvasääskiä sekä tyrninokkaluteita. Kirvojen määrä tunneleista laskettiin joka viikko ja samalla havainnoitiin hyötyeliöiden sekä tuhoeliöiden esiintyvyyttä tunneleissa.
Ensimmäiset kirvahavainnot tunneleissa tehtiin heinäkuussa. Suurin osa havaituista kirvoista oli pikkuvattukirvan siivetöntä muotoa. BerryProtect -putkilo oli toimiva ennakkotorjunnassa. Kirvasääski torjui tehokkaammin toisessa tunnelissa, kun taas toisessa tyrninokkalude oli tehokkaampi. Näillä levitysstrategioilla saatiin kuitenkin Wennborgin tilan kannalta toimiva lopputulos
Immunogenicity and safety of a booster dose of the 13-valent pneumococcal conjugate vaccine in children primed with the 10-valent or 13-valent pneumococcal conjugate vaccine in the Czech Republic and Slovakia
Background:
Although both the 13-valent pneumococcal conjugate vaccine (PCV13) and the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D-conjugate vaccine (PHiD-CV) are widely used, it is unclear how interchangeable they are in terms of immunogenicity.
Methods:
Two phase 3, open-label, multicenter studies were conducted to assess the immunogenicity and safety of a booster dose of PCV13 in children primed with PHiD-CV or PCV13. In the Czech Republic, 12–15-month-old children received a PCV13 booster after 3-dose priming with either PHiD-CV or PCV13. In Slovakia, 11–12-month-old children received PCV13 following 2-dose priming with either PHiD-CV or PCV13. Serum IgG concentrations were assessed by enzyme-linked immunosorbent assay and functional antibodies were assessed by opsonophagocytic assay (OPA) before the booster and at 1 and 12 months afterward. The primary objective of these studies was to assess non-inferiority of OPA titers for serotype 19A in PHiD-CV-primed subjects compared to those in PCV13-primed children 1 month post-booster.
Results:
A total of 98 subjects in the Czech Republic and 89 subjects in Slovakia were included. One month after the PCV13 booster dose, the IgG and OPA immune responses to serotype 19A in subjects primed with 2 or 3 doses of PHiD-CV were non-inferior to those in subjects primed with PCV13. Non-inferior and persistent immune responses to most other vaccine serotypes were also observed after the PCV13 booster in PHiD-CV-primed subjects. No safety issues were raised in either study.
Conclusions:
Overall, robust IgG and OPA immunological responses were observed after booster vaccination with PCV13 in children primed with 2 or 3 doses of PHiD-CV or PCV13, including for serotypes not included in PHiD-CV. These results suggest that these vaccines are interchangeable in terms of safety and immunogenicity and that PCV13 can be used as a booster in the context of mixed schedules. (EudraCT numbers: 2012-005366-35 and 2012-005367-27)
Numerical study of the thermoelectric power factor in ultra-thin Si nanowires
Low dimensional structures have demonstrated improved thermoelectric (TE)
performance because of a drastic reduction in their thermal conductivity,
{\kappa}l. This has been observed for a variety of materials, even for
traditionally poor thermoelectrics such as silicon. Other than the reduction in
{\kappa}l, further improvements in the TE figure of merit ZT could potentially
originate from the thermoelectric power factor. In this work, we couple the
ballistic (Landauer) and diffusive linearized Boltzmann electron transport
theory to the atomistic sp3d5s*-spin-orbit-coupled tight-binding (TB)
electronic structure model. We calculate the room temperature electrical
conductivity, Seebeck coefficient, and power factor of narrow 1D Si nanowires
(NWs). We describe the numerical formulation of coupling TB to those transport
formalisms, the approximations involved, and explain the differences in the
conclusions obtained from each model. We investigate the effects of cross
section size, transport orientation and confinement orientation, and the
influence of the different scattering mechanisms. We show that such methodology
can provide robust results for structures including thousands of atoms in the
simulation domain and extending to length scales beyond 10nm, and point towards
insightful design directions using the length scale and geometry as a design
degree of freedom. We find that the effect of low dimensionality on the
thermoelectric power factor of Si NWs can be observed at diameters below ~7nm,
and that quantum confinement and different transport orientations offer the
possibility for power factor optimization.Comment: 42 pages, 14 figures; Journal of Computational Electronics, 201
Electron effective mobility in strained Si/Si1-xGex MOS devices using Monte Carlo simulation
Based on Monte Carlo simulation, we report the study of the inversion layer
mobility in n-channel strained Si/ Si1-xGex MOS structures. The influence of
the strain in the Si layer and of the doping level is studied. Universal
mobility curves mueff as a function of the effective vertical field Eeff are
obtained for various state of strain, as well as a fall-off of the mobility in
weak inversion regime, which reproduces correctly the experimental trends. We
also observe a mobility enhancement up to 120 % for strained Si/ Si0.70Ge0.30,
in accordance with best experimental data. The effect of the strained Si
channel thickness is also investigated: when decreasing the thickness, a
mobility degradation is observed under low effective field only. The role of
the different scattering mechanisms involved in the strained Si/ Si1-xGex MOS
structures is explained. In addition, comparison with experimental results is
discussed in terms of SiO2/ Si interface roughness, as well as surface
roughness of the SiGe substrate on which strained Si is grown.Comment: 25 pages, 8 figures, 1 table, revised version, discussions and
references adde
Multilab EcoFAB study shows highly reproducible physiology and depletion of soil metabolites by a model grass
There is a dynamic reciprocity between plants and their environment: soil physiochemical properties influence plant morphology and metabolism, and root morphology and exudates shape the environment surrounding roots. Here, we investigate the reproducibility of plant trait changes in response to three growth environments. We utilized fabricated ecosystem (EcoFAB) devices to grow the model grass Brachypodium distachyon in three distinct media across four laboratories: phosphate-sufficient and -deficient mineral media allowed assessment of the effects of phosphate starvation, and a complex, sterile soil extract represented a more natural environment with yet uncharacterized effects on plant growth and metabolism. Tissue weight and phosphate content, total root length, and root tissue and exudate metabolic profiles were consistent across laboratories and distinct between experimental treatments. Plants grown in soil extract were morphologically and metabolically distinct, with root hairs four times longer than with other growth conditions. Further, plants depleted half of the metabolites investigated from the soil extract. To interact with their environment, plants not only adapt morphology and release complex metabolite mixtures, but also selectively deplete a range of soil-derived metabolites. The EcoFABs utilized here generated high interlaboratory reproducibility, demonstrating their value in standardized investigations of plant traits
Low-dimensional phonon transport effects in ultranarrow disordered graphene nanoribbons
Immunogenicity, transplacental transfer of pertussis antibodies and safety following pertussis immunization during pregnancy: Evidence from a randomized, placebo-controlled trial.
Background: Pertussis immunization during pregnancy is recommended in many countries. Data from
large randomized controlled trials are needed to assess the immunogenicity, reactogenicity and safety
of this approach.
Methods: This phase IV, observer-blind, randomized, placebo-controlled, multicenter trial assessed
immunogenicity, transplacental transfer of maternal pertussis antibodies, reactogenicity and safety of
a reduced-antigen-content diphtheria-tetanus-three-component acellular pertussis vaccine (Tdap) during
pregnancy. Women received Tdap or placebo at 27–36 weeks’ gestation with crossover 72-hourpostpartum
immunization. Immune responses were assessed before the pregnancy dose and 1 month
after, and from the umbilical cord at delivery. Superiority (primary objective) was reached if the lower
limits of the 95% confidence intervals (CIs) of the pertussis geometric mean concentration (GMC) ratios
(Tdap/control) in cord blood were 1.5. Solicited and unsolicited adverse events (AEs) and pregnancy-/
neonate-related AEs of interest were recorded.
Results: 687 pregnant women were vaccinated (Tdap: N = 341 control: N = 346). Superiority of the pertussis
immune response (maternally transferred pertussis antibodies in cord blood) was demonstrated
by the GMC ratios (Tdap/control): 16.1 (95% CI: 13.5–19.2) for anti-filamentous hemagglutinin, 20.7
(15.9–26.9) for anti-pertactin and 8.5 (7.0–10.2) for anti-pertussis toxoid. Rates of pregnancy-/
neonate-related AEs of interest, solicited general and unsolicited AEs were similar between groups.
None of the serious AEs reported throughout the study were considered related to maternal Tdap vaccination.
Conclusions: Tdap vaccination during pregnancy resulted in high levels of pertussis antibodies in cord
blood, was well tolerated and had an acceptable safety profile. This supports the recommendation of
Tdap vaccination during pregnancy to prevent early-infant pertussis disease.post-print502 K
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