755 research outputs found
First record of Penthalodes ovalis (Dugès, 1834) in agricultural area with notes on its pest status (Acari: Penthalodidae)
The first record of species Penthalodes ovalis (Dugès, 1834) in agricultural habitat is presented in this paper. This is also the first record of the occurrence and damages on grown plants. The variability of the morphology and new data on the biology are given as well
Photoemission Electron Microscopy as a tool for the investigation of optical near fields
Photoemission electron microscopy was used to image the electrons
photoemitted from specially tailored Ag nanoparticles deposited on a Si
substrate (with its native oxide SiO). Photoemission was induced by
illumination with a Hg UV-lamp (photon energy cutoff eV,
wavelength nm) and with a Ti:Sapphire femtosecond laser
( eV, nm, pulse width below 200 fs),
respectively. While homogeneous photoelectron emission from the metal is
observed upon illumination at energies above the silver plasmon frequency, at
lower photon energies the emission is localized at tips of the structure. This
is interpreted as a signature of the local electrical field therefore providing
a tool to map the optical near field with the resolution of emission electron
microscopy.Comment: 10 pages, 4 figures; submitted to Physical Review Letter
Supported polysilsesquioxane membrane and production thereof
Membranes of the invention comprise a hybrid silica film on a organic polymer support. The silica comprises organic bridging groups bound to two or more silicon atoms, in particular at least 1 of said organic bridging groups per 10 silicon atoms. The membranes can be produced by dry chemistry processes, in particular plasma-enhanced vapour deposition of bridged silane precursors, or by wet chemistry involving hydrolysis of the bridged silane precursors. The membranes are inexpensive and efficient for separation of small molecules and filtration processes
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Report of the AD HOC Study Group on integrated versus dispersed fuel cycle facilities
To provide isolation of strategic materials and confinement of nuclear wastes, the basic facilities considered in assessing the DFCF and IFCF were mixed plutonium and uranium oxide and HTGR fuel fabrication, fuel reprocessing, high- enrichment isotopic separation and interim waste storage. Reactors, low- enrichment isotopic separation, and low-enrichment uranium facilities were excluded. It is expected that the IFCF would attract uranium fuel fabrication and possibly reactors. An assumption was made for the study that the choice of either IFCF or DFCF would not alter the nuclear power generation pattern postulated to exist up to the year 2000. The advantages of IFCF are seen to outweigh disadvantages. (auth
Photonic mode density effects on single-molecule fluorescence blinking
We investigated the influence of the photonic mode density (PMD) on the
triplet dynamics of individual chromophores on a dielectric interface by
comparing their response in the presence and absence of a nearby gold film.
Lifetimes of the excited singlet state were evaluated in ordet to measure
directly the PMD at the molecules position. Triplet state lifetimes were
simultaneously determined by statistical analysis of the detection time of the
fluorescence photons. The observed singlet decay rates are in agreement with
the predicted PMD for molecules with different orientations. The triplet decay
rate is modified in a fashion correlated to the singlet decay rate. These
results show that PMD engineering can lead to an important suppression of the
fluorescence, introducing a novel aspect of the physical mechanism to enhance
fluorescence intensity in PMD-enhancing systems such as plasmonic devices
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Weight Loss and Illness Severity in Adolescents With Atypical Anorexia Nervosa.
BACKGROUND:Lower weight has historically been equated with more severe illness in anorexia nervosa (AN). Reliance on admission weight to guide clinical concern is challenged by the rise in patients with atypical anorexia nervosa (AAN) requiring hospitalization at normal weight. METHODS:We examined weight history and illness severity in 12- to 24-year-olds with AN (n = 66) and AAN (n = 50) in a randomized clinical trial, the Study of Refeeding to Optimize Inpatient Gains (www.clinicaltrials.gov; NCT02488109). Amount of weight loss was the difference between the highest historical percentage median BMI and admission; rate was the amount divided by duration (months). Unpaired t tests compared AAN and AN; multiple variable regressions examined associations between weight history variables and markers of illness severity at admission. Stepwise regression examined the explanatory value of weight and menstrual history on selected markers. RESULTS:Participants were 16.5 ± 2.6 years old, and 91% were of female sex. Groups did not differ by weight history or admission heart rate (HR). Eating Disorder Examination Questionnaire global scores were higher in AAN (mean 3.80 [SD 1.66] vs mean 3.00 [SD 1.66]; P = .02). Independent of admission weight, lower HR (β = -0.492 [confidence interval (CI) -0.883 to -0.100]; P = .01) was associated with faster loss; lower serum phosphorus was associated with a greater amount (β = -0.005 [CI -0.010 to 0.000]; P = .04) and longer duration (β = -0.011 [CI -0.017 to 0.005]; P = .001). Weight and menstrual history explained 28% of the variance in HR and 36% of the variance in serum phosphorus. CONCLUSIONS:Weight history was independently associated with markers of malnutrition in inpatients with restrictive eating disorders across a range of body weights and should be considered when assessing illness severity on hospital admission
Natural enemies of armored scales (Hemiptera: Diaspididae) and soft scales (Hemiptera: Coccoidae) in Chile: molecular and morphological identification.
Scale insects (Hemiptera: Sternorrhyncha: Coccomorpha) are key pests of agricultural
crops and ornamental plants worldwide. Their populations are difficult to control, even with
insecticides, due to their cryptic habits. Moreover, there is growing concern over the use of
synthetic pesticides for their control, due to deleterious environmental effects and the emergence
of resistant populations of target pests. In this context, biological control may be an
effective and sustainable approach. Hymenoptera Chalcidoidea includes natural enemies of
scale insects that have been successfully used in many biological control programs. However,
the correct identification of pest scale species and their natural enemies is particularly
challenging because these insects are very small and highly specialized. Integrative taxonomy,
coupling DNA barcoding and morphological analysis, has been successfully used to
characterize pests and natural enemy species. In this study, we performed a survey of parasitoids
and predators of armored and soft scales in Chile, based on 28S and COI barcodes.
Fifty-three populations of Diaspididae and 79 populations of Coccidae were sampled over
the entire length of the country, from Arica (18ËšS) to Frutillar (41ËšS), between January 2015
and February 2016. The phylogenetic relationships obtained by Bayesian inference from
multilocus haplotypes revealed 41 putative species of Chalcidoidea, five Coccinellidae and
three Neuroptera. Species delimitation was confirmed using ABGD, GMYC and PTP model.
In Chalcidoidea, 23 species were identified morphologically, resulting in new COI barcodes
for 12 species and new 28S barcodes for 14 species. Two predator species (Rhyzobius
lophantae and Coccidophilus transandinus) were identified morphologically, and two parasitoid
species, Chartocerus niger and Signiphora bifasciata, were recorded for the first time
in Chile
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