41,934 research outputs found
Fluctuations in Number of Cercospora beticola Conidia in Relationship to Environment and Disease Severity in Sugar Beet
All content of Phytopathology is open access without restriction 12 months after publicationCercospora leaf spot, caused by Cercospora beticola, is the most damaging foliar disease of sugar beet in Minnesota (MN) and North Dakota (ND). Research was conducted to characterize the temporal progression of aerial concentration of C. beticola conidia in association with the environment and disease severity in sugar beet. In 2003 and 2004, volumetric spore traps were placed within inoculated sugar beet plots to determine daily dispersal of conidia at Breckenridge, MN, and St. Thomas, ND. Plots were rated weekly for disease severity. At both locations, conidia were first collected in early July 2003 and late June in 2004. Peaks of conidia per cubic meter of air were observed with maxima in late August 2003 and in early September 2004 at both locations. Peaks of airborne conidium concentration were significantly correlated with the average temperature of daily hours when relative humidity was greater than 87%. Weekly mean hourly conidia per cubic meter of air was significantly (P <0.01) associated with disease severity during both years and across locations. This study showed that C. beticola conidial numbers may be used to estimate potential disease severity that, with further research, could be incorporated in a disease forecasting model to rationalize Cercospora leaf spot management.Peer reviewe
Anthropic tuning of the weak scale and of m_u/m_d in two-Higgs-doublet models
It is shown that in a model in which up-type and down-type fermions acquire
mass from different Higgs doublets, the anthropic tuning of the Higgs mass
parameters can explain the fact that the observed masses of the and
quarks are nearly the same with slightly heavier. If Yukawa couplings are
assumed not to "scan" (vary among domains), this would also help explain why
the t quark is much heavier than the b quark. It is also pointed out that the
existence of dark matter invalidates some earlier anthropic arguments against
the viability of domains where the Standard Model Higgs has positive ,
but makes other even stronger arguments possible.Comment: 31 pages, 7 figure
Self-Similar Graphs
For any graph on vertices and for any {\em symmetric} subgraph of
, we construct an infinite sequence of graphs based on the pair
. The First graph in the sequence is , then at each stage replacing
every vertex of the previous graph by a copy of and every edge of the
previous graph by a copy of the new graph is constructed. We call these
graphs {\em self-similar} graphs. We are interested in delineating those pairs
for which the chromatic numbers of the graphs in the sequence are
bounded. Here we have some partial results. When is a complete graph and
is a special matching we show that every graph in the resulting sequence is
an {\em expander} graph.Comment: 13 pages, 1 tabl
Submm-bright X-ray absorbed QSOs at z~2: insights into the co-evolution of AGN and star-formation
We have assembled a sample of 5 X-ray-absorbed and submm-luminous type 1 QSOs
at which are simultaneously growing their central black holes
through accretion and forming stars copiously. We present here the analysis of
their rest-frame UV to submm Spectral Energy Distributions (SEDs), including
new Herschel data. Both AGN (direct and reprocessed) and Star Formation (SF)
emission are needed to model their SEDs. From the SEDs and their UV-optical
spectra we have estimated the masses of their black holes , their intrinsic AGN bolometric luminosities
, Eddington ratios
and bolometric corrections
. These values are common among optically and
X-ray-selected type 1 QSOs (except for RX~J1249), except for the bolometric
corrections, which are higher. These objects show very high far-infrared
luminosities (2 - 8) and Star Formation
Rates SFRy. From their and the shape of their
FIR-submm emission we have estimated star-forming dust masses of . We have found evidence of a tentative correlation between the
gas column densities of the ionized absorbers detected in X-ray (N)
and . Our computed black hole masses are amongst the most massive known.Comment: Accepted for publication in MNRAS, December 22, 2014, 17 pages, 5
figure
Allergic bronchopulmonary aspergillosis: an unusual complication of bronchial asthma
Asthma is a common medical problem in Pakistan. Allergic Bronchopulmonary Aspergillosis (ABPA), an immune mediated disease, is an unusual complication of bronchial asthma which can result in bronchiectasis, pulmonary fibrosis, respiratory failure and death. Early diagnosis is important so that with proper therapy permanent lung damage can be prevented. First described in 19521 , ABPA was thought to be a rare disorder, but with increased awareness amongst the physicians and better diagnostic techniques, äases are being recognized more frequently. The clinical features of ABPA (cough, fever, hemoptysis and lung infiltrates) are usually mistaken for pulmonary tuberculosis (TB). We present three cases in which failure to consider the diagnosis of ABPA resulted in repeated courses of anti-TB therapy and/or progressive lung damage and continued morbidit
Modeling the gravitational wave signature of neutron star black hole coalescences: PhenomNSBH
Accurate gravitational-wave (GW) signal models exist for black-hole binary (BBH) and neutron-star binary (BNS) systems, which are consistent with all of the published GW observations to date. Detections of a third class of compact-binary systems, neutron-star-black-hole (NSBH) binaries, have not yet been confirmed, but are eagerly awaited in the near future. For NSBH systems, GW models do not exist across the viable parameter space of signals. In this work we present the frequency-domain phenomenological model, PhenomNSBH, for GWs produced by NSBH systems with mass ratios from equal-mass up to 15, spin on the black hole up to a dimensionless spin of , and tidal deformabilities ranging from 0 (the BBH limit) to 5000. We extend previous work on a phenomenological amplitude model for NSBH systems to produce an amplitude model that is parameterized by a single tidal deformability parameter. This amplitude model is combined with an analytic phase model describing tidal corrections. The resulting approximant is accurate enough to be used to measure the properties of NSBH systems for signal-to-noise ratios (SNRs) up to 50, and is compared to publicly-available NSBH numerical-relativity simulations and hybrid waveforms constructed from numerical-relativity simulations and tidal inspiral approximants. For most signals observed by second-generation ground-based detectors within this SNR limit, it will be difficult to use the GW signal alone to distinguish single NSBH systems from either BNSs or BBHs, and therefore to unambiguously identify an NSBH system
Evaluation of a Proposed Dust Ventilation/Collection System in an Underground Mine Crushing Plant
Computational Fluid Dynamics (CFD) modelling of a dust collection system in an underground mine crushing plant was carried out. Dust was collected/absorbed through the holes along the top edge of Run of Mine (ROM) bin. The dust collection performance of the system is summarised. The detail results are presented in the form of velocity vectors and dust concentration iso-surface contours. Time dependent dust concentration isosurfaces are also presented. Dust was found to be well contained within the crusher bin and stands out as a viable option. However, the velocity magnitudes were found to be very high in and around the whole exits, which has the potential to lead to undesirable pressure drop and generation of noise
Smoking prevalence, knowledge and attitudes among medical students in Karachi, Pakistan
A survey of smoking prevalence and attitudes was made among medical students randomly selected from classes at the Aga Khan University, Karachi, Pakistan. Of 271 respondents, 14.4% were current smokers (22.0% male and 3.8% females) and 3.3% ex-smokers. A majority of students recognized the dangers associated with active as well as passive smoking although only 55% of current smokers planned to quit in the near future. Most smokers (96%) believed that they as well as other health professionals needed training on smoking cessation and 95% of all students believed that doctors should play a role model in smoking cessation by not smoking themselves. Specific training and counselling should be a part of the required curriculum at medical schools
Fast track children's hearing pilot: final report of the evaluation of the pilot
This report presents key findings of the evaluation of the Fast Track children’s hearings pilot in Scotland1. The research was undertaken by staff at the Universities of Glasgow, Stirling and Strathclyde between February 2003 and January 2005
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