1,231 research outputs found
Distribution and biology of the yellow-spotted longicorn beetle Psacothea hilaris hilaris(Pascoe) in Italy
The Asiatic yellow-spotted longicorn beetle, Psacothea hilaris hilaris, was found for the first time in Northern Italy in 2005. As this xylophagous insect is considered one of the most important pests of Morus spp. and of Ficus carica in its countries of origin, a multiyear study was carried out to determine the spread of the pest in Northern Italy, to evaluate its establishment potential and to improve knowledge on its biology in the new habitat. The survey confirmed that P. hilaris hilaris has established in Italy and has colonized an area of about 60 km2. The species overwinters as eggs or larvae. Adults are present from June to October. Damage has been recorded mostly on Ficus carica plants, and very rarely on Morus alba. Both young and older plants, healthy and weakened hosts can be attacked by the pest. Severely attacked plants become weakened and eventually die.Psacothea hilaris hilaris, (capricorne asiatique a taches jaunes) a ete identifie en Italie septentrionale pour la premiere fois en 2005. Puisque cet insecte xylophage est considere comme un des ravageurs les plus importants de Morus spp. et de Ficus carica dans sa zone d\u2019origine, une etude pluriannuelle a ete entreprise pour determiner la dissemination de cet organisme nuisible dans le nord de l\u2019Italie, determiner son potentiel d\u2019etablissement, et ameliorer les connaissances sur sa biologie dans ce nouvel habitat. Les resultats confirment que P. hilaris hilaris s\u2019est etabli en Italie et a colonise une zone d\u2019environ 60 km\ub2. Cette espece passe l\u2019hiver sous forme d\u2019oeuf ou de larve.
Les adultes sont presents de juin a octobre. Les degats ont principalement ete observes sur des Ficus carica, et tres rarement sur Morus alba. Le ravageur attaque aussi bien les plantes jeunes qu\u2019agees, saines que malades. Les plantes severement atteintes sont affaiblies, et finissent par mourir
Stratospheric sudden warmings in an idealized GCM
PublishedJournal ArticleAn idealized general circulation model (GCM) with an analytically described Newtonian cooling term is employed to study the occurrence rate of sudden stratospheric warmings (SSWs) over a wide range of parameters. In particular, the sensitivity of the SSW occurrence rates to orographic forcing and both relaxation temperature and damping rate is evaluated. The stronger the orographic forcing and the weaker the radiative forcing (in both temperature and damping rate), the higher the SSW frequency. The separate effects of the damping rates at low and high latitudes are somewhat more complex. Generally, lower damping rates result in higher SSW frequency. However, if the low- and high-latitude damping rates are not the same, SSW frequency tends to be most sensitive to a fractional change in the lower of the two damping rates. In addition, the effect of the damping rates on the stratospheric residual circulation is investigated. It is found that higher high-latitude damping rate results in deeper but narrower circulation, whereas higher low-latitude damping rates cause strengthening of the stream function in the tropical midstratosphere to upper stratosphere. Finally, the relation between easily measured and compared climatological fields and the SSW occurrence rate is determined. The average stratospheric polar zonal mean zonal wind shows a strong anticorrelation with the SSW frequency. In the troposphere, there is a high correlation between the meridional temperature gradient and SSW frequency, suggesting that the strength of synoptic activity in the troposphere may be an important influence on SSW occurrence.National Science FoundationSwiss National Science Foundatio
The Impact of Split and Displacement Sudden Stratospheric Warmings on the Troposphere
Although sudden stratospheric warmings (SSWs) can improve subseasonal-to-seasonal forecasts, it is unclear whether the two types of SSW - displacements and splits - have different near-surface effects. To examine the longer-term (i.e., multi-week lead) tropospheric response to displacements and splits, we utilize an intermediate-complexity model and impose wave-1 and wave-2 stratospheric heating perturbations spun-off from a control run. At longer lags, the tropospheric response is found to be insensitive to both the wavenumber and location of the imposed heating, in agreement with freely evolving displacements and splits identified in the control run. At shorter lags, however, large differences are found between displacements and splits in both the control run and the different wavenumber-forced events. In particular, in the control run, the free-running splits have an immediate barotropic response throughout the stratosphere and troposphere whereas displacements take 1–2 weeks before a near-surface response becomes evident. Interestingly, this barotropic response found during CTRL splits is not captured by the barotropically forced wave-2 events, indicating that the zonal-mean tropospheric circulation is somehow coupled with the generation of the wave-2 splits. It is also found that in the control run, displacements yield stronger Polar-Cap temperature anomalies than splits, yet both still yield similar magnitude tropospheric responses. Hence, the strength of the stratospheric warming is not the only governing factor in the surface response. Overall, SSW classification based on vortex morphology may be useful for subseasonal but not seasonal tropospheric prediction
What Counts in Brain Aging? Design-Based Stereological Analysis of Cell Number
The advent and implementation of new design-based stereological techniques allows the quantification of cell number without the assumptions required when obtaining areal densities. These new techniques are rapidly becoming the standard for quantifying cell number, particularly in aging studies. Recently, studies using stereological techniques have failed to confirm earlier findings regarding age-associated neural loss. This newly emerging view of retained cell number during aging is having a major impact on biogerontology, prompting revaluation of long-standing hypotheses of age-related cell loss as causal for age-related impairments in brain functioning. Rather than focus on neuronal loss as the end-result of a negative cascade of neuronal injury, research has begun to consider that age-related behavioral declines may reflect neuronal dysfunction (e.g., synaptic or receptor loss, signal transduction deficits) instead of neuronal death. Here we discuss design-based stereology in the context of age-related change in brain cell number and its impact on consideration of structural change in brain aging. Emergence of this method of morphometries, however, can have relevance to many areas of gerontological researc
Evaluation of a therapy protocol for the treatment of chronic digital dermatitis in European bison (Bison bonasus)
Digital dermatitis (DD) associated with the presence of multiple Treponema
spp. was recently described for the first time in European bison (Bison
bonasus). DD is characterized by skin inflammation in the distal foot area
in various ungulates. The objective of this proof of concept study was
to test a treatment protocol adopted from cattle for its applicability in
this wildlife species using five animals. Keratolytic salicylic acid paste was
administered topically under bandages for seven days to enable removal of the
Power requirements for electron cyclotron current drive and ion cyclotron resonance heating for sawtooth control in ITER
13MW of electron cyclotron current drive (ECCD) power deposited inside the q
= 1 surface is likely to reduce the sawtooth period in ITER baseline scenario
below the level empirically predicted to trigger neo-classical tearing modes
(NTMs). However, since the ECCD control scheme is solely predicated upon
changing the local magnetic shear, it is prudent to plan to use a complementary
scheme which directly decreases the potential energy of the kink mode in order
to reduce the sawtooth period. In the event that the natural sawtooth period is
longer than expected, due to enhanced alpha particle stabilisation for
instance, this ancillary sawtooth control can be provided from > 10MW of ion
cyclotron resonance heating (ICRH) power with a resonance just inside the q = 1
surface. Both ECCD and ICRH control schemes would benefit greatly from active
feedback of the deposition with respect to the rational surface. If the q = 1
surface can be maintained closer to the magnetic axis, the efficacy of ECCD and
ICRH schemes significantly increases, the negative effect on the fusion gain is
reduced, and off-axis negative-ion neutral beam injection (NNBI) can also be
considered for sawtooth control. Consequently, schemes to reduce the q = 1
radius are highly desirable, such as early heating to delay the current
penetration and, of course, active sawtooth destabilisation to mediate small
frequent sawteeth and retain a small q = 1 radius.Comment: 29 pages, 16 figure
- …