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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

Population-based study of survival for women with serous cancer of the ovary, fallopian tube, peritoneum or undesignated origin - on behalf of the Swedish gynecological cancer group (SweGCG)

Objective: The aim of the study was to determine survival outcome in patients with serous cancer in the ovary, fallopian tube, peritoneum and of undesignated origin. Methods: Nation-wide population-based study of women. ≥. 18. years with histologically verified non-uterine serous cancer, included in the Swedish Quality Registry for primary cancer of the ovary, fallopian tube and peritoneum diagnos

Clonal conversion of B lymphoid leukemia reveals cross-lineage transfer of malignant states

Even though leukemia is considered to be confined to one specific hematopoietic cell type, cases of acute leukemia of ambiguous lineage and patients relapsing in phenotypically altered disease suggest that a malignant state may be transferred between lineages. Because B-cell leukemia is associated with mutations in transcription factors of importance for stable preservation of lineage identity, we

Clinical outcomes of negative small-bowel capsule endoscopy for small-bowel bleeding : A systematic review and meta-analysis

Background and Aims: Small-bowel bleeding is the primary indication for capsule endoscopy (CE). Many experts advocate a "watch-and-wait" policy in negative CE. This meta-analysis examines the odds of rebleeding after negative index CE and the impact on long-term follow-up. Methods: A comprehensive literature search identified articles examining the rebleeding rate after negative CE. Demographic an

Local food in Iceland : Identifying behavioral barriers to increased production and consumption

Increased production and consumption of local food may reduce the negative environmental, social, and economic impacts of industrialized and globalized food production. Here we examined potential barriers to increasing production and consumption of food produced in Iceland. First, we developed a new framework to address the behaviors of production and consumption simultaneously, to comprehensively

Negotiating Control : From Recognizing a Need to Making a Decision to Apply for a Housing Adaptation

A housing adaptation (HA) can enable independent living in one's own home, but deciding to change the home environment can be a thought-provoking matter. The aim of this study was to explore the applicant's perspective and decision-making process when applying for an HA grant. Seventeen persons were interviewed about their application for such a grant, and the data were analyzed using a constant c

The prevalence, population structure and screening test specificity of penicillin-susceptible Staphylococcus aureus bacteremia isolates in Malmö, Sweden

Objectives The objectives of this study were to examine the prevalence of penicillin-susceptible bacteremic Staphylococcus aureus in the Malmö area in 2014, to re-evaluate the phenotypic methods of penicillinase detection on these isolates, and to investigate the clonal distribution of penicillin-susceptible isolates. Methods All non-redundant S. aureus from blood in the Malmö catchment area in so

Implementation of Models of Care for secondary osteoporotic fracture prevention and orthogeriatric Models of Care for osteoporotic hip fracture

As the world's population ages, the prevalence of osteoporosis and its resultant fragility fractures is set to increase dramatically. This chapter focuses on current frameworks and major initiatives related to the implementation of fracture liaison services (FLS) and orthogeriatrics services (OGS), Models of Care designed to reliably implement secondary fracture prevention measures for individuals

Contact allergy in atopic individuals in relation to allergen-specific immunotherapy

Background: Type I sensitizations and atopic dermatitis (AD) often appear in the same patient. Beneficial effects of allergen-specific immunotherapy (ASIT) in patients with bothADand type I allergies have been reported. The predisposing role of AD to the development of type IV sensitization is discussed. Whether ASIT for type I allergy also influences type IV allergies is unknown. Objectives: To c

Differential Equations with Infinitely Many Derivatives and the Borel Transform

Differential equations with infinitely many derivatives, sometimes also referred to as “nonlocal” differential equations, appear frequently in branches of modern physics such as string theory, gravitation and cosmology. We properly interpret and solve linear equations in this class with a special focus on a solution method based on the Borel transform. This method is a far-reaching generalization