676 research outputs found
Germ-furrow morphology and storage conditions determine the degree of viability of Pinus caribaea pollen
This study has found a correlation between Pinus caribaea pollen morphology and viability. Eighteen different P. caribaea pollen families were screened to determine the effect of environmental conditions during storage on germination. The results indicated that there was a direct decrease in viability with an increase in the age of the pollen, temperature at which the pollen was stored, and exposure to high humidity during storage. Scanning electron microscopy was used to investigate the dimensions of the 18 families. Upon statistical analysis of the dimensional data, the families were found to group into three clusters. Pollen families displaying narrow germ furrows clustered with those displaying wide germ furrows, while those pollen families displaying intermediate germ furrows clustered into a second group. When the clusters were compared with the germination data obtained it was found that the pollen families displaying highest germination percentages fell into the intermediate cluster, while the pollen families displaying low to intermediate germination percentages fell into the narrow/wide cluster
Gossip in organisations: Contexts, consequences and controversies
This article examines the key themes surrounding gossip including its contexts, the various outcomes (positive and negative) of gossip as well as a selection of challenges and controversies. The challenges which are highlighted revolve around definitional issues, methodological approaches, and ethical considerations. Our analysis suggests that the characteristics and features of gossip lend itself to a process-oriented approach whereby the beginning and, particularly, end points of gossip are not always easily identified. Gossip about a subject or person can temporarily disappear only for it to re-surface at some later stage. In addition, questions pertaining to the effects of gossip and ethical-based arguments depend on the nature of the relationships within the gossip triad (gossiper, listener/respondent and target)
Ivermectin and albendazole coadministration: opportunities for strongyloidiasis control
7 pĂĄginas.In 2020, WHO recognised the importance of strongyloidiasis alongside soil-transmitted helminths (STH) in their
2021â30 roadmap, which aspires to target Strongyloides stercoralis with preventive chemotherapy by use of ivermectin.
Combination treatment with both albendazole, the primary drug used to treat STH, and ivermectin, would improve
the efficiency of mass drug administration targeting both STH and S stercoralis. In this Personal View, we discuss the
challenges and opportunities towards the development of an efficient control programme for strongyloidiasis,
particularly if it is to run concurrently with STH control. We argue the need to define the prevalence threshold to
implement preventive chemotherapy for S stercoralis, the target populations and optimal dosing schedules, and
discuss the added benefits of a fixed-dose coformulation of ivermectin and albendazole. Implementation of an
efficient control programme will require improvements to current diagnostics, and validation of new diagnostics, to
target and monitor S stercoralis infections, and consideration of the challenges of multispecies diagnostics for
S stercoralis and STH control. Finally, the evolution of ivermectin resistance represents a credible risk to control
S stercoralis; we argue that genome-wide approaches, together with improved genome resources, are needed to
characterise and prevent the emergence of resistance. Overcoming these challenges will help to reduce strongyloidiasis
burden and enhance the feasibility of controlling it worldwide.Our group, the Stopping Transmission of intestinal Parasites (STOP)
consortium, is funded by the EDCTP2 programme supported by the
European Union (RIA2017NCT-1845-STOP). The Barcelona Institute for
Global Health (ISGlobal) acknowledges support from the Spanish
Ministry of Science and Innovation and State Research Agency through
the Centro de Excelencia Severo Ochoa 2019â2023 Program
(CEX2018-000806-S) and support from the Generalitat de Catalunya
through the CERCA Program. SRD is supported by a UK Research and
Innovation Future Leaders Fellowship [MR/T020733/1] and the
Wellcome Trust through core funding to the Wellcome Sanger Institute
[108413/A/15/D]. MC-P is supported by the Junta de Castilla y LeĂłn and
Fondo Social Europeo. The funders of the study had no role in the
manuscript preparation or the decision to publish. The views, opinions,
assumptions, or any other information set out in this Personal View are
solely those of the authors and should not be attributed to the funders or
any person connected with the funders.Peer reviewe
D* Production in Deep Inelastic Scattering at HERA
This paper presents measurements of D^{*\pm} production in deep inelastic
scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The
data have been taken with the ZEUS detector at HERA. The decay channel
(+ c.c.) has been used in the study. The
cross section for inclusive D^{*\pm} production with
and is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region
{ GeV and }. Differential cross
sections as functions of p_T(D^{*\pm}), and are
compared with next-to-leading order QCD calculations based on the photon-gluon
fusion production mechanism. After an extrapolation of the cross section to the
full kinematic region in p_T(D^{*\pm}) and (D^{*\pm}), the charm
contribution to the proton structure function is
determined for Bjorken between 2 10 and 5 10.Comment: 17 pages including 4 figure
Observation of Scaling Violations in Scaled Momentum Distributions at HERA
Charged particle production has been measured in deep inelastic scattering
(DIS) events over a large range of and using the ZEUS detector. The
evolution of the scaled momentum, , with in the range 10 to 1280
, has been investigated in the current fragmentation region of the Breit
frame. The results show clear evidence, in a single experiment, for scaling
violations in scaled momenta as a function of .Comment: 21 pages including 4 figures, to be published in Physics Letters B.
Two references adde
Observation of hard scattering in photoproduction events with a large rapidity gap at HERA
Events with a large rapidity gap and total transverse energy greater than 5
GeV have been observed in quasi-real photoproduction at HERA with the ZEUS
detector. The distribution of these events as a function of the
centre of mass energy is consistent with diffractive scattering. For total
transverse energies above 12 GeV, the hadronic final states show predominantly
a two-jet structure with each jet having a transverse energy greater than 4
GeV. For the two-jet events, little energy flow is found outside the jets. This
observation is consistent with the hard scattering of a quasi-real photon with
a colourless object in the proton.Comment: 19 pages, latex, 4 figures appended as uuencoded fil
PEArL: a systems approach to demonstrating authenticity in information systems design
The process of information systems (IS) design has been dominated by the demands inherent in providing a technical solution to a perceived problem or need. Engineering IS design methods applied in order to satisfy the problem situation tend to have a preoccupation with verifying specifications as being mathematically correct. Diffculties arise when the ideas underpinning verification are extended in an attempt to âproveâ the validity of a proposed design for an IS. A pure engineering approach does not facilitate a response to the subjective elements within social situations, which experience has shown to be essential in demonstrating the pertinence of new designs to those concerned. We suggest that, by applying interpretivist systems ideas, it is possible to support concerned individuals in reflecting upon crucial aspects of the inquiry, enabling those individuals to judge the relevance or âauthenticityâ of the learning, according to their own values and beliefs. The elements of participants, engagement, authority, relationships and learning are suggested as being crucial. These make up the mnemonic PEArL, which is offered as an aide-mĂ©moire for those concerned with IS design
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
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