417 research outputs found
Applying generic landscape-scale models of natural pest control to real data: Associations between crops, pests and biocontrol agents make the difference
Managing agricultural land to maximize the supply of natural pest control can help reduce pesticide use. Tools that are able to represent the relationship between landscape structure, field management and natural pest control can help in deciding which management practices should be used and where. However, the reliability and the predictive power of generic models of natural pest control is largely unknown. We applied an existing generic model of natural pest control potential based on landscape structure to nine sites in five European countries and tested the resulting values against field measurements of natural pest control. Subsequently, we added information on local level factors to test the possibility of improving model performance and predictive power. The results showed that there is generally little or no evidence of correlation between modeled and field-measured values of natural pest control. Moreover, we found high variability in the results, depending on the associations of crops, pests and biocontrol agents considered (e.g. Oilseed rape-Pollen beetle-Parasitoids) and on the different case studies. Factors at the local level, such as conservation tillage, had an overall positive effect on natural pest control, and their inclusion in the models typically increased their predictive power. Our results underline the importance of developing predictive models of natural pest control which are tailored towards specific associations between crops, pests and biocontrol agents, consider local level factors and are trained using field measurements. They would serve as important tools within farmers' decision making, ultimately supporting the shift toward a low-pesticide agriculture
Will Remote Sensing Shape the Next Generation of Species Distribution Models?
Two prominent limitations of species distribution models (SDMs) are spatial biases in existing occurrence data and a lack of spatially explicit predictor variables to fully capture habitat characteristics of species. Can existing and emerging remote sensing technologies meet these challenges and improve future SDMs? We believe so. Novel products derived from multispectral and hyperspectral sensors, as well as future Light Detection and Ranging (LiDAR) and RADAR missions, may play a key role in improving model performance. In this perspective piece, we demonstrate how modern sensors onboard satellites, planes and unmanned aerial vehicles are revolutionizing the way we can detect and monitor both plant and animal species in terrestrial and aquatic ecosystems as well as allowing the emergence of novel predictor variables appropriate for species distribution modeling. We hope this interdisciplinary perspective will motivate ecologists, remote sensing experts and modelers to work together for developing a more refined SDM framework in the near future
Scanning-helium-ion-beam lithography with hydrogen silsesquioxane resist
A scanning-helium-ion-beam microscope is now commercially available. This microscope can be used to perform lithography similar to, but of potentially higher resolution than, scanning electron-beam lithography. This article describes the control of this microscope for lithography via beam steering/blanking electronics and evaluates the high-resolution performance of scanning helium-ion-beam lithography. The authors found that sub-10 nm-half-pitch patterning is feasible. They also measured a point-spread function that indicates a reduction in the micrometer-range proximity effect typical in electron-beam lithography.National Science Foundation (U.S.). Graduate Research Fellowship Progra
Weak localization of light by cold atoms: the impact of quantum internal structure
Since the work of Anderson on localization, interference effects for the
propagation of a wave in the presence of disorder have been extensively
studied, as exemplified in coherent backscattering (CBS) of light. In the
multiple scattering of light by a disordered sample of thermal atoms,
interference effects are usually washed out by the fast atomic motion. This is
no longer true for cold atoms where CBS has recently been observed. However,
the internal structure of the atoms strongly influences the interference
properties. In this paper, we consider light scattering by an atomic dipole
transition with arbitrary degeneracy and study its impact on coherent
backscattering. We show that the interference contrast is strongly reduced.
Assuming a uniform statistical distribution over internal degrees of freedom,
we compute analytically the single and double scattering contributions to the
intensity in the weak localization regime. The so-called ladder and crossed
diagrams are generalized to the case of atoms and permit to calculate
enhancement factors and backscattering intensity profiles for polarized light
and any closed atomic dipole transition.Comment: 22 pages Revtex, 9 figures, to appear in PR
Retinopatia da prematuridade e sua importância clÃnica na atualidade
A retinopatia da prematuridade (ROP) é uma doença multifatorial de crianças prematuras, associada principalmente ao muito baixo peso e a reduzida idade gestacional. É a patologia ocular mais frequente na neonatologia. É uma doença onde o pré-termo nasce com a retina parcialmente avascular, pois os vasos não se desenvolveram até a direção da periferia da retina, gerando um vaso proliferação irregular, fibrose e prejudicando a função ocular e seu crescimento. Em grande parte dessa população de prematuros, a regressão espontânea acontece, com a maturação do recém-nascido (RN) ela vai involuindo até a retina voltar a sua condição fisiológica correta. Muitos dos prematuros que desenvolvem as fases mais avançadas, vão ter complicações como a miopia. Um terço das crianças com peso menor de 1.500 gramas ao nascimento pode apresentar ROP. Destas, pensando menos de 1.251 gramas ao nascer 65,8% podem desenvolver ROP, enquanto 81,6% das com menos de 1.000 gramas podem ser acometidas. A ROP se tornou uma das maiores causas de cegueira infantil, em paÃses desenvolvidos, devido a maior sobrevivência de RN prematuros. Foram analisadas diversas revisões sistemáticas abordando a ROP até o presente ano de 2010. Onde as abordagens mais utilizadas de critérios diagnósticos e clÃnicos foram selecionadas e citadas. Junto de uma atualização clÃnica sobre a patologia, com intuito de abordar os fatores predisponentes e os aspectos caracterÃsticos da doença, orientando os profissionais de saúde a diagnosticar precocemente e tratar os RN portadores de ROP. No Brasil, estima-se que a cada ano sobrevivem em torno de 15.000 prematuros em risco de desenvolver ROP, os quais necessitam de exame de triagem para o diagnóstico. O consenso atual define que o mais importante é o acompanhamento criterioso dos prematuros quando detectamos as alterações, determinando assim a localização, extensão e fase de desenvolvimento o mais precocemente possÃvel
Epidermolysa bullosa in Danish Hereford calves is caused by a deletion in LAMC2 gene
BACKGROUND
Heritable forms of epidermolysis bullosa (EB) constitute a heterogeneous group of skin disorders of genetic aetiology that are characterised by skin and mucous membrane blistering and ulceration in response to even minor trauma. Here we report the occurrence of EB in three Danish Hereford cattle from one herd.
RESULTS
Two of the animals were necropsied and showed oral mucosal blistering, skin ulcerations and partly loss of horn on the claws. Lesions were histologically characterized by subepidermal blisters and ulcers. Analysis of the family tree indicated that inbreeding and the transmission of a single recessive mutation from a common ancestor could be causative. We performed whole genome sequencing of one affected calf and searched all coding DNA variants. Thereby, we detected a homozygous 2.4 kb deletion encompassing the first exon of the LAMC2 gene, encoding for laminin gamma 2 protein. This loss of function mutation completely removes the start codon of this gene and is therefore predicted to be completely disruptive. The deletion co-segregates with the EB phenotype in the family and absent in normal cattle of various breeds. Verifying the homozygous private variants present in candidate genes allowed us to quickly identify the causative mutation and contribute to the final diagnosis of junctional EB in Hereford cattle.
CONCLUSIONS
Our investigation confirms the known role of laminin gamma 2 in EB aetiology and shows the importance of whole genome sequencing in the analysis of rare diseases in livestock
Seismogenic faults, landslides, and associated tsunamis off southern Italy - Cruise No. M86/2, December 27, 2011 - January 17, 2012, Cartagena (Spain) - Brindisi (Italy)
Summary
The continental margins of southern Italy are located along converging plate boundaries, which
are affected by intense seismicity and volcanic activity. Most of the coastal areas experienced
severe earthquakes, landslides, and tsunamis in historical and/or modern times. The most
prominent example is the Messina earthquake of Dec. 28, 1908 (Ms=7.3; 80,000 casualties),
which was characterized by the worst tsunami Italy experienced in the historical time (~2000
casualties). It is, however, still unclear, whether this tsunami was triggered by a sudden vertical
movement along a major fault during the earthquake or as a result of a giant marine slide
initiated by the earthquake. The recurrence rates of major landslides and therefore the risk
associated with landslides is also unknown. Based on detailed bathymetric data sets collected by
Italian colleagues in the frame of the MaGIC Project (Marine Geohazards along the Italian
Coast), we collected seismic data (2D and 3D) and gravity cores in three working areas (The
Messina Straits, off Eastern Sicily, the Gioia Basin). A dense grid of new 2D-seismic data in the
Messina Straits will allow to map fault patterns in great detail. One interesting outcome in this
context is the identification of a set of normal faults striking in an EW-direction, which is almost
perpendicular to the previously postulated faults. This EW-striking faults seem to be active. The
area off eastern Sicily is characterized by numerous landslides and a complex deformation
pattern. A 3D-seismic data set has been collected during the cruise using the so called P-cable in
order to investigate these deformation patterns in detail. The new data will be the basis for a risk
assessment in the working areas
Deep structure of the Ionian Sea and Sicily Dionysus - Cruise No. M111, October 10 - November 1, 2014, Catania (Italy) – Catania (Italy)
Summary
The origin of the Ionian Sea lithosphere and the deep structure of its margins remain a little
investigated part of the Mediterranean Sea. To shed light on the plate tectonic setting in this
central part of southern Europe, R/V METEOR cruise M111 set out to acquire deep penetrating
seismic data in the Ionian Sea. M111 formed the core of an amphibious investigation covering
the Ionian Sea and island of Sicily. A total of 153 OBS/OBH deployments using French and
German instruments were successfully carried out, in addition to 12 land stations installed on
Sicily, which recorded the offshore air gun shots.
The aim of this onshore-offshore study is to quantify the deep geometry and architecture of the
Calabria subduction zone and Ionian Sea lithosphere and to shed light on the nature of the Ionian
Sea crust (oceanic crust vs. thinned continental crust). Investigating the structure of the Ionian
crust and lithospheric mantle will contribute to unravel the unknown ocean-continent transition
and Tethys margin. Analyzing the tectonic activity and active deformation zones is essential for
understanding the subduction processes that underlie the neotectonics of the Calabrian
subduction zone and earthquake hazard of the Calabria/Sicily region, especially in the vicinity of
local decoupling zones
Targeting the Neurokinin Receptor 1 with Aprepitant: A Novel Antipruritic Strategy
Chronic pruritus is a global clinical problem with a high impact on the quality of life and lack of specific therapies. It is an excruciating and frequent symptom of e.g. uncurable renal, liver and skin diseases which often does not respond to conventional treatment with e.g. antihistamines. Therefore antipruritic therapies which target physiological mechanisms of pruritus need to be developed. Substance P (SP) is a major mediator of pruritus. As it binds to the neurokinin receptor 1 (NKR1), we evaluated if the application of a NKR1 antagonist would significantly decrease chronic pruritus.Twenty hitherto untreatable patients with chronic pruritus (12 female, 8 male; mean age, 66.7 years) were treated with the NKR1 antagonist aprepitant 80 mg for one week. 16 of 20 patients (80%) experienced a considerable reduction of itch intensity, as assessed by the visual analog scale (VAS, range 0 to 10). Considering all patients, the mean value of pruritus intensity was significantly reduced from 8.4 VAS points (SD +/-1.7) before treatment to 4.9 VAS points (SD +/-3.2) (p<0.001, CI 1.913-5.187). Patients with dermatological diseases (e.g. atopic diathesis, prurigo nodularis) had the best profit from the treatment. Side-effects were mild (nausea, vertigo, and drowsiness) and only occurred in three patients.The high response rate in patients with therapy refractory pruritus suggests that the NKR1 antagonist aprepitant may indeed exhibit antipruritic effects and may present a novel, effective treatment strategy based on pathophysiology of chronic pruritus. The results are promising enough to warrant confirming the efficacy of NKR1 antagonists in a randomized, controlled clinical trial
A second horizon scan of biogeography:golden ages, Midas touches, and the Red Queen
Are we entering a new ‘Golden Age’ of biogeography, with continued development of infrastructure
and ideas? We highlight recent developments, and the challenges and opportunities they bring, in
light of the snapshot provided by the 7th biennial meeting of the International Biogeography Society
(IBS 2015). We summarize themes in and across 15 symposia using narrative analysis and word
clouds, which we complement with recent publication trends and ‘research fronts’. We find that
biogeography is still strongly defined by core sub-disciplines that reflect its origins in botanical,
zoological (particularly bird and mammal), and geographic (e.g., island, montane) studies of the
1800s. That core is being enriched by large datasets (e.g. of environmental variables, ‘omics’,
species’ occurrences, traits) and new techniques (e.g., advances in genetics, remote sensing,
modeling) that promote studies with increasing detail and at increasing scales; disciplinary
breadth is being diversified (e.g., by developments in paleobiogeography and microbiology) and
integrated through the transfer of approaches and sharing of theory (e.g., spatial modeling and
phylogenetics in evolutionary–ecological contexts). Yet some subdisciplines remain on the fringe
(e.g., marine biogeography, deep-time paleobiogeography), new horizons and new theory may be
overshadowed by popular techniques (e.g., species distribution modelling), and hypotheses, data,
and analyses may each be wanting. Trends in publication suggest a shift away from traditional
biogeography journals to multidisciplinary or open access journals. Thus, there are currently many stewardship of, the planet (e.g., Intergovernmental Science-Policy Platform on Biodiversity and
Ecosystem Services). As in the past, biogeographers doubtless will continue to be engaged by
new data and methods in exploring the nexus between biology and geography for decades into
the future. But golden ages come and go, and they need not touch every domain in a discipline
nor affect subdisciplines at the same time; moreover, what appears to be a Golden Age may
sometimes have an undesirable ‘Midas touch’. Contexts within and outwith biogeography—e.g.,
methods, knowledge, climate, biodiversity, politics—are continually changing, and at times it can
be challenging to establish or maintain relevance. In so many races with the Red Queen, we
suggest that biogeography will enjoy greatest success if we also increasingly engage with the
epistemology of our disciplinePeer reviewe
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