542 research outputs found
Using particle size analysis to determine the hydrophobicity and suspension of fungal conidia with particular relevance to formulation of biopesticide
Fungal formulations are vital for effective biopesticide development. Good formulations help to optimise field efficacy while poor formulations result in product failure. This study aimed to produce a hydrophobicity test that would be appropriate for fungal conidia produced to a commercial quality and determine relative hydrophobicity of fungi from four different genera by using laser diffraction. A particle size analyser was used to determine the hydrophobicity of: three Metarhizium acridum samples, M. anisopliae, Beauveria bassiana, Trichoderma stromaticum, T. harzianum, T. viride and Alternaria eichhorniae conidia, by suspending the conidia in three different liquids: Shellsol T (a mineral oil), water and 0.05 % Tween 80. Hydrophobicity was determined by the size of the particles formed in each of the liquids. All the Metarhizium samples were the most hydrophobic followed by B. bassiana and A. eichhorniae. The Trichoderma samples were the least hydrophobic. As a comparison a phase exclusion assay and a salt-mediated aggregation and sedimentation (SAS) test were performed. It was not possible to get a reliable reading for the B. bassiana, A. eichhorniae and T. viride samples using the phase exclusion assay. The addition of salt in the SAS test did not affect the rate of sedimentation. It was hypothesised that conidia size affected the results of the SAS test that made A. eichhorniae the most hydrophobic conidia. Particle size analysis was a more accurate test for comparing fungi from difference genera compared to the SAS test and phase exclusion assay. PSA was also used to test three emulsions and demonstrated that different formulations had an effect on particle size
The Harmonic Lattice, Recoilless Transitions, And The Coherent State
The probability for recoilless transitions, relevant for the understanding of x-ray scattering from atoms bound in a crystal (applicable also to elastic scattering of neutrons from solids and to the Mossbauer effect), given by the Debye-Waller factor, is derived in a novel manner using the coherent state basis for the normal mode oscillators describing the harmonic lattice, a method which, while being simple and elegant, also reveals the relationship to a heuristic classical discussion of the problem
A category-specific advantage for numbers in verbal short-term memory: Evidence from semantic dementia
This study explored possible reasons for the striking difference between digit span and word span in patients with semantic dementia. Immediate serial recall (ISR) of number and non-number words was examined in four patients. For every case, the recall of single-digit numbers was normal whereas the recall of non-number words was impaired relative to controls. This difference extended to multi-digit numbers, and remained even when frequency, imageability, word length, set size and size of semantic category were matched for the numbers and words. The advantage for number words also applied to the patients' reading performance. Previous studies have suggested that semantic memory plays a critical role in verbal short-term memory (STM) and reading: patients with semantic dementia show superior recall and reading of words that are still relatively well known compared to previously known but now semantically degraded words. Additional assessments suggested that this semantic locus was the basis of the patients' category-specific advantage for numbers. Comprehension was considerably better for number than non-number words. Number knowledge may be relatively preserved in semantic dementia because the cortical atrophy underlying the condition typically spares the areas of the parietal lobes thought to be crucial in numerical cognition but involves the inferolateral temporal-lobes known to support general conceptual knowledge. © 2003 Elsevier Ltd. All rights reserved
A dynamic magneto-optical trap for atom chips
We describe a dynamic magneto-optical trap (MOT) suitable for the use with vacuum systems in which optical access is limited to a single window. This technique facilitates the long-standing desire of producing integrated atom chips, many of which are likely to have severely restricted optical access compared with conventional vacuum chambers. This "switching-MOT" relies on the synchronized pulsing of optical and magnetic fields at audio frequencies. The trap's beam geometry is obtained using a planar mirror surface, and does not require a patterned substrate or bulky optics inside the vacuum chamber. Central to the design is a novel magnetic field geometry that requires no external quadrupole or bias coils which leads toward a very compact system. We have implemented the trap for 85Rb and shown that it is capable of capturing 2 million atoms and directly cooling below the Doppler temperature
Temporal stability and transferability of models of willingness to pay for flood control and wetland conservation
Nonmarket valuation of water quality in a rural transition economy in Turkey applying an a posteriori bid design
In this paper, we investigate the economic benefits associated with public investments in wastewater treatment in one of the special protected areas along Turkey's touristic Mediterranean coast, the Köyceǧiz-Dalyan watershed. The benefits, measured in terms of boatable, fishable, swimmable and drinkable water quality, are estimated using a public survey format following the contingent valuation (CV) method. The study presented here is the first of its kind in Turkey. The study's main objective is to assess public perception, understanding, and valuation of improved wastewater treatment facilities in the two largest population centers in the watershed, facing the same water pollution problems as a result of lack of appropriate wastewater treatment. We test the validity and reliability of the application of the CV methodology to this specific environmental problem in a rural transition economy and evaluate the transferability of the results within the watershed. In order to facilitate willingness to pay (WTP) value elicitation we apply a novel dichotomous choice procedure where bid design takes place a posteriori instead of a priori. The statistical efficiency of different bid vectors is evaluated in terms of the estimated welfare measures' mean square errors using Monte Carlo simulation. The robustness of bid function specification is analyzed through average WTP and standard deviation estimated using parametric and nonparametric methods. Copyright 2007 by the American Geophysical Union
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Some toxicity data and their practical significance
Information reviewed and reaffirmed June, 1959. Date of original report January 19, 1937
Antiviral treatment for Bell's palsy (idiopathic facial paralysis)
BACKGROUND: Antiviral agents against herpes simplex virus are widely used in the treatment of idiopathic facial paralysis (Bell's palsy), but their effectiveness is uncertain. Significant morbidity can be associated with severe cases. OBJECTIVES: This review addresses the effect of antiviral therapy on Bell's palsy. SEARCH STRATEGY: We updated the search of the Cochrane Neuromuscular Disease Group Trials Register (December 2008), MEDLINE (from January 1966 to December 8 2008), EMBASE (from January 1980 to December 8 2008) and LILACS (from January 1982 to December 2008). SELECTION CRITERIA: Randomized trials of antivirals with and without corticosteroids versus control therapies for the treatment of Bell's palsy. DATA COLLECTION AND ANALYSIS: Twenty-three papers were selected for consideration. MAIN RESULTS: Seven trials including 1987 participants met the inclusion criteria, adding five studies to the two in the previous review.Incomplete recovery at one year. There was no significant benefit in the rate of incomplete recovery from antivirals compared with placebo (n = 1886, RR 0.88, 95% CI 0.65 to 1.18). In meta-analyses with some unexplained heterogeneity, the outcome with antivirals was significantly worse than with corticosteroids (n = 768, RR 2.82, 95% CI 1.09 to 7.32) and the outcome with antivirals plus corticosteroids was significantly better than with placebo (n = 658, RR 0.56, 95% CI 0.41 to 0.76).Motor synkinesis or crocodile tears at one year. In single trials, there was no significant difference in long term sequelae comparing antivirals and corticosteroids with corticosteroids alone (n = 99, RR 0.39, 95% CI 0.14 to 1.07) or antivirals with corticosteroids (n = 101, RR 1.03, 95% CI 0.51 to 2.07).Adverse events.There was no significant difference in rates of adverse events between antivirals and placebo (n = 1544, RR 1.06, 95% CI 0.81 to 1.38), between antivirals and corticosteroids (n = 667, RR 0.96, 95% CI 0.65 to 1.41) or between the antiviral-corticosteroid combination and placebo (n = 658, RR 1.15, 95% CI 0.79 to 1.66). AUTHORS' CONCLUSIONS: High quality evidence showed no significant benefit from anti-herpes simplex antivirals compared with placebo in producing complete recovery from Bell's palsy. Moderate quality evidence showed that antivirals were significantly less likely than corticosteroids to produce complete recovery.</p
Five new real-time detections of Fast Radio Bursts with UTMOST
We detail a new fast radio burst (FRB) survey with the Molonglo Radio
Telescope, in which six FRBs were detected between June 2017 and December 2018.
By using a real-time FRB detection system, we captured raw voltages for five of
the six events, which allowed for coherent dedispersion and very high time
resolution (10.24 s) studies of the bursts. Five of the FRBs show temporal
broadening consistent with interstellar and/or intergalactic scattering, with
scattering timescales ranging from 0.16 to 29.1 ms. One burst, FRB181017, shows
remarkable temporal structure, with 3 peaks each separated by 1 ms. We searched
for phase-coherence between the leading and trailing peaks and found none,
ruling out lensing scenarios. Based on this survey, we calculate an all-sky
rate at 843 MHz of events sky day to a fluence
limit of 8 Jy-ms: a factor of 7 below the rates estimated from the Parkes and
ASKAP telescopes at 1.4 GHz assuming the ASKAP-derived spectral index
(). Our results suggest that FRB
spectra may turn over below 1 GHz. Optical, radio and X-ray followup has been
made for most of the reported bursts, with no associated transients found. No
repeat bursts were found in the survey.Comment: 13 pages, 11 figures, submitted to MNRA
Three-dimensional simulations of the interstellar medium in dwarf galaxies - II. Galactic wind
We study the hydrodynamical evolution of galactic winds in disky dwarf
galaxies moving through an intergalactic medium. In agreement with previous
investigations,we find that when the ram pressure stripping does not disrupt
the ISM, it usually has a negligible effect on the galactic wind dynamics. Only
when the IGM ram pressure is comparable to the central ISM thermal pressure the
stripping and the superwind influence each other increasing the gas removal
rate. In this case several parameters regulate the ISM ejection process, as the
original distribution of the ISM and the geometry of the IGM-galaxy
interaction. When the ISM is not removed by the ram pressure or the wind, it
loses memory of the starburst episode and recovers almost its pre-burst
distribution in a timescale of 50-200 Myr. After this time another star
formation episode becomes, in principle, possible. Evidently, galactic winds
are consistent with a recurrent bursts star formation history.
Contrary to the ISM content, the amount of the metal-rich ejecta retained by
the galaxy is more sensitive to the ram pressure action. Part of the ejecta is
first trapped in a low density, extraplanar gas produced by the IGM-ISM
interaction, and then pushed back onto the galactic disc. The amount of trapped
metals in a moving galaxy may be up to three times larger than in a galaxy at
rest. This prediction may be tested comparing metallicity of dwarf galaxies in
nearby poor clusters or groups, such as Virgo or Fornax, with the field
counterpart. The sensitivity of the metal entrapment efficiency on the geometry
of the interaction may explain part of the observed scatter in the
metallicity-luminosity relation for dwarf galaxies.Comment: Accepted MNRAS, 9 color figure
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