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The draft genome of whitefly Bemisia tabaci MEAM1, a global crop pest, provides novel insights into virus transmission, host adaptation, and insecticide resistance

Background: The whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is among the 100 worst invasive species in the world. As one of the most important crop pests and virus vectors, B. tabaci causes substantial crop losses and poses a serious threat to global food security. Results: We report the 615-Mb high-quality genome sequence of B. tabaci Middle East-Asia Minor 1 (MEAM1), the first genome sequen

Evaluating early-warning indicators of critical transitions in natural aquatic ecosystems

Ecosystems can show sudden and persistent changes in state despite only incremental changes in drivers. Such critical transitions are difficult to predict, because the state of the system often shows little change before the transition. Early-warning indicators (EWIs) are hypothesized to signal the loss of system resilience and have been shown to precede critical transitions in theoretical models,

High-contrast imaging through scattering media using structured illumination and Fourier filtering

We show in this Letter a novel approach for high-contrast imaging through scattering media by combining structured illumination and Fourier filtering (SIF). To assess the image contrast enhancement at different image spatial frequencies, the modulation transfer function is calculated for four detection schemes: (1) no filtering, (2) Fourier filtering, (3) structured illumination, and (4) SIF filte

Holographic imaging with a hard x-ray nanoprobe : Ptychographic versus conventional phase retrieval

We have performed near-field x-ray imaging with simultaneous object and probe reconstruction. By an advanced ptychographic algorithm based on longitudinal and lateral translations, full-field images of nanoscale objects are reconstructed with quantitative contrast values, along with the extended wavefronts used to illuminate the objects. The imaging scheme makes idealizing assumptions on the probe

Homocysteine regulates endothelin type B receptors in vascular smooth muscle cells

Vascular smooth muscle endothelin type B (ETB) receptor is involved in the pathogenesis of cardiovascular diseases (CVDs). Hyperhomocysteinemia is an independent risk factor for CVDs. The present study was designed to examine the hypothesis that homocysteine (Hcy) up-regulates vascular smooth muscle ETB receptors. In vitro experiments were performed in rat superior mesenteric artery (SMA) and vasc

Threshold π - production on the deuteron

An experiment that aims to measure the π- photoproduction cross-section σ(E) on the deuteron γ + 2H → π- + 2p near threshold is discussed. The main concepts of the experimental technique are presented alongside some preliminary signals.

Conjugate priors for Gaussian emission plsa recommender systems

Collaborative filtering for recommender systems seeks to learn and predict user preferences for a collection of items by identifying similarities between users on the basis of their past interest or interaction with the items in question. In this work, we present a conjugate prior regularized extension of Hofmann's Gaussian emission probabilistic latent semantic analysis model, able to overcome th

Electron dynamics in solar energy converting materials

Solar energy is the most abundant renewable energy source available. Conversion of light into electricity and chemical energy are the two major paths for solar energy conversion. Nanostructured organic and hybrid materials are being explored for applications in photovoltaic solar energy conversion, as well as photocatalysis for solar fuel generation. Light harvesting, energy transport, charge phot

On a fixed-point algorithm for structured low-rank approximation and estimation of half-life parameters

We study the problem of decomposing a measured signal as a sum of decaying exponentials. There is a direct connection to sums of these types and positive semi-definite (PSD) Hankel matrices, where the rank of these matrices equals the number of exponentials. We propose to solve the identification problem by forming an optimization problem with a misfit function combined with a rank penalty functio

Characterization of non-vertically aligned semiconductor nanowires by THz emission measurements

In this work terahertz (THz) pulse emission of the non-vertically aligned GaAs core-shell nanowires (NWs) is investigated. THz emission azimuthal dependencies of different NW samples have been measured. It is shown that these measurements together with theoretical calculations could be a very promising method to determine the effective index of refraction (n0) of the NW ensemble. The measurement o

Helicity-dependent terahertz radiation from topological insulator Sb2Te3 thin film by femtosecond optical excitation

We report on terahertz radiation from topological insulator (TI) Sb2Te3 thin film under ultrafast optical excitation with different helicity. Polarity-reversals of the emitted THz radiation were observed as the helicity of optical pulses reversed. The observed phenomena are coincident with the characteristics of the helicity-dependent photocurrent on TIs. Our work demonstrates the potential applic

Healthcare system : A digital green filter for smart health early cervical cancer diagnosis

A color conversion digital filter is implemented which represents a block of a medical imaging system able to assist gynecologists during colposcopic image analysis is presented. The conceived tool is a monitoring system in the field smart health; in fact an early diagnosis could improve the quality of life and the life expectancy of patients. Tree different digital green filters are conceived and

Proximity and power in collaborative innovation projects

Proximity and power in collaborative innovation projects. Regional Studies. The proximity literature has so far paid little attention to power relations in collaborative innovation projects. This paper draws on contributions from international business to examine if power constellations between collaborators in innovation projects influence the effects of proximity. An analysis of two cases of col

Policing Migration: Described and Observed Cooperation Experiences of Police and Border Guards in the Baltic Sea Area

“Collaboration” is generally portrayed as being beneficial to intelligence and operational police work, even if previous collaborative research shows that conflicts are common between authorities who are supposed to cooperate. The present study focuses on how officers collaborate in their day-to-day management of borderguarding, taking into consideration the different social and cultural backgroun“Collaboration” is generally portrayed as being beneficial to intelligence and operational police work, even if previous collaborative research shows that conflicts are common between authorities who are supposed to cooperate. The present study focuses on how officers collaborate in their day-to-day management of border guarding, taking into consideration the different social and cultural backgrou

Distribution and surface enrichment of radionuclides in lead-bismuth eutectic from spallation targets

With the development of new high-power neutron spallation sources --both for scientific application and as neutron production tool for accelerator-driven systems-- the demand for experimentally obtained nuclear data on the residue nuclei production in the target is constantly increasing. In the present work, we examined two lead-bismuth-eutectic targets, irradiated with high-energy protons, concer

Low Incubation Temperature Induces DNA Hypomethylation in Lizard Brains

Developmental stress can have organizational effects on suites of physiological, morphological, and behavioral characteristics. In lizards, incubation temperature is perhaps the most significant environmental variable affecting embryonic development. Wall lizards (Podarcis muralis) recently introduced by humans from Italy to England experience stressfully cool incubation conditions, which we here