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Theory and measurements of harmonic generation in semiconductor superlattices with applications in the 100 GHz to 1 THz range

This manuscript describes harmonic generation in semiconductor superlattices, starting from a nonequilibrium Green's functions input to relaxation rate-type analytical approximations for the Boltzmann equation in which imperfections in the structure lead to asymmetric current flow and scattering processes under forward and reverse bias. The resulting current-voltage curves and the predicted conseq

X-ray Bragg Ptychography on a Single InGaN/GaN Core-Shell Nanowire

The future of solid-state lighting can be potentially driven by applications of InGaN/GaN core-shell nanowires. These heterostructures provide the possibility for fine-tuning of functional properties by controlling a strain state between mismatched layers. We present a nondestructive study of a single 400 nm-thick InGaN/GaN core-shell nanowire using two-dimensional (2D) X-ray Bragg ptychography (X

Development of Stable Long-term Electrode Tissue Interfaces for Recording and Stimulation

Summary: Brain Computer interfaces (BCIs) are stable inside the brain over long periods of time and that have minimal effects on the physiological conditions of the neural tissue. This chapter reviews the state-of-the-art of neural interfaces and the concepts behind recent research and development of biocompatible BCIs. It focuses on various tissue responses in the brain to an implanted foreign bo

Disassembly of Dipeptide Single Crystals Can Transform the Lipid Membrane into a Network

Coupling between cytoskeleton and membranes is critical to cell movement as well as organelle formation. Here, we demonstrate that self-assembled single crystals of a dipeptide, diphenylalanine (FF), can interact with liposomes to form cytoskeleton-like structures. Under a physiological condition, disassembly of FF crystals deforms and translocates supported lipid membrane. The system exhibits sim

Carbon credits compete poorly with agricultural commodities in an optimized model of land use in Northern California

Nascent US carbon markets reward farmers for reforesting agricultural land, with consequent ecological co-benefits. We use a dynamic optimization model to determine the likelihood of an orchard farmer in northern California converting to forest under 90 plausible future scenarios. We find reforestation to be a highly unlikely outcome, occurring only 4.0% of the time under current economic, biophys

Subsidies in aviation

Relatively little attention has been paid to the existence of subsidies in aviation. As the sector's importance for economic development is often highlighted, this paper seeks to provide a conceptual overview of the various forms of subsidies in aviation, as a contribution to a more holistic understanding of economic interrelationships. Based on a purposive sampling strategy, existing forms of sub

Inter- and intra-rater reliability of the head-shaft angle in children with cerebral palsy

Purpose. Children with cerebral palsy (CP) are at increased risk for hip dislocation. This can be prevented in most cases using surveillance programmes that include radiographic examinations. Known risk factors for hip dislocation include young age, high Gross Motor Function Classification System (GMFCS) level and high migration percentage (MP). The head-shaft angle (HSA) has recently been describ

Single and multiple cardiovascular biomarkers in subjects without a previous cardiovascular event

Aims To assess the incremental value of biomarkers, including N-terminal prohormone of brain natriuretic peptide (NT-proBNP), high-sensitivity troponin T (hs-TnT), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), growth differentiation factor 15 (GDF-15), and procollagen type 1 N-terminal propeptide (P1NP), in predicting incident cardiovascular events and mortality among asympto

A disease-specific questionnaire for measuring patient-reported outcomes and experiences in the Swedish National Diabetes Register : Development and evaluation of content validity, face validity, and test-retest reliability

Objective: To describe the development and evaluation of the content and face validity and test-retest reliability of a disease-specific questionnaire that measures patient-reported outcomes and experiences for the Swedish National Diabetes Register for adult patients who have type 1 or type 2 diabetes. Methods: In this methodological study, a questionnaire was developed over four phases using an

Cardiovascular risk after hospitalisation for unexplained syncope and orthostatic hypotension

OBJECTIVE: To investigate the relationship of hospital admissions due to unexplained syncope and orthostatic hypotension (OH) with subsequent cardiovascular events and mortality.METHODS: We analysed a population-based prospective cohort of 30 528 middle-aged individuals (age 58±8 years; males, 40%). Adjusted Cox regression models were applied to assess the impact of unexplained syncope/OH hospital

N-Terminal Prosomatostatin and Risk of Vascular Dementia

BACKGROUND: Increased somatostatin plasma concentration has been found in patients with vascular dementia. However, it is unknown whether or not somatostatin levels may predict dementia development in the general population. To this end, we sought to assess the association of circulating N-terminal prosomatostatin (NT-proSST) with incident dementia among community-dwelling older adults.METHODS: In

Early vascular ageing (EVA) : Definitions and clinical applicability

Arterial stiffness has been accumulating evidence as an intermediate cardiovascular endpoint. It has been established as an independent risk marker for cardiovascular disease, and reflects the dissociation between chronologic and biologic age of large arteries-attributing earlier the risk that a normal vascular ageing process had installed to occur several years later. The concept of Early Vascula

Compression therapy for venous leg ulcers : Risk factors for adverse events and complications, contraindications - a review of present guidelines

Introduction: The adequate use of compression in venous leg ulcer treatment is equally important to patients as well as clinicians. Currently, there is a lack of clarity on contraindications, risk factors, adverse events and complications, when applying compression therapy for venous leg ulcer patients. Methods: The project aimed to optimize prevention, treatment and maintenance approaches by reco

Beam shaping with 4n-order multipole magnets

A uniformly irradiating beam is beneficial in spallation for preventing irregular wear on the target. For octupoles (n = 4) and higher-order (n = 4N) magnets, passing charged-particle bunches undergo symmetric shaping effects along the x and y axes. Using a Lie-mapping formalism, we illustrate how well Gaussian distributions can be flattened symmetrically in 2D with single, dual-pulse, and RF magn

Application of whole-exome sequencing to direct the specific functional testing and diagnosis of rare inherited bleeding disorders in patients from the Öresund Region, Scandinavia

Rare inherited bleeding disorders (IBD) are a common cause of bleeding tendency. To ensure a correct diagnosis, specialized laboratory analyses are necessary. This study reports the results of an upfront diagnostic strategy using targeted whole exome sequencing. In total, 156 patients with a significant bleeding assessment tool score participated in the study, of which a third had thrombocytopenia

Approximating nonlinear forces with phase-space decoupling

Beam tracking software for accelerators typically falls into two categories: fast envelope simulations limited to linear beam optics, and slower multiparticle simulations that can model nonlinear effects. To find a middle ground between these approaches, we introduce virtual coordinates in position and momentum which have a cross-dependency (i.e. p∗ = f (x 0) where x 0 is an initial position and p

Pathophysiology of meningioma growth in pregnancy

Meningioma is among the most frequent brain tumours predominantly affecting elderly women. Epidemiological studies have shown that at the age of fertility the incidence is relatively low. The biological behaviour of meningioma in pregnancy is different from other meningiomas. The possible explanation is rooted in the complex physiological changes and hormonal differences during pregnancy. The incr

Urinary Extracellular Vesicles of Podocyte Origin and Renal Injury in Preeclampsia

Renal histologic expression of the podocyte-specific protein, nephrin, but not podocin, is reduced in preeclamptic compared with normotensive pregnancies. We hypothesized that renal expression of podocyte-specific proteins would be reflected in urinary extracellular vesicles (EVs) of podocyte origin and accompanied by increased urinary soluble nephrin levels (nephrinuria) in preeclampsia. We furth

Improved positioning and detectability of microparticles in droplet microfluidics using two-dimensional acoustophoresis

We have fabricated a silicon-glass two-phase droplet microfluidic system capable of generating sub 100 μm-sized, ø = (74 ± 2) μm, spherical droplets at rates of up to hundreds of hertz. By implementing a two-dimensional (2D) acoustophoresis particle-positioning method, we show a fourfold improvement in both vertical and lateral particle positioning inside the droplets compared to unactuated operat