Publications by authors named "Ole Hansen"

Anisotropic heat-conducting materials play crucial roles in designing electronic, optoelectronic, and thermoelectric devices, where temperature and thermal stress are important. Despite substantial research efforts, a major obstacle to determining the anisotropic thermal diffusivity tensor in polycrystalline systems is the need for a robust, direct, and nondestructive technique to distinguish between distinct thermal diffusivities. Here, we demonstrate a conceptually unique thermal diffusivity microscope capable of performing high-resolution local measurements of anisotropic thermal diffusivity.

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Premise: Leveraging DNA markers, particularly single-nucleotide polymorphisms (SNPs), in parentage analysis, sib-ship reconstruction, and genomic relatedness analysis can enhance plant breeding efficiency. However, the limited availability of genomic information, confined to the most commonly used species, hinders the broader application of SNPs in species of lower economic interest (e.g.

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A wafer-scale process for fabricating monolithically suspended nano-perforated membranes (NPMs) with integrated support structures into silicon is developed. Existing fabrication methods are suitable for many desired geometries, but face challenges related to mechanical robustness and fabrication complexity. We demonstrate a process that utilizes the cyclic deposit, remove, etch, and multi-step (DREM) process for directional etching of high-aspect-ratio (HAR) 300 nm in diameter nano-pores of 700 nm pitch.

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Magnetron sputtering is a versatile method for investigating model system catalysts thanks to its simplicity, reproducibility, and chemical-free synthesis process. It has recently emerged as a promising technique for synthesizing δ-NiGa thin films. Physically deposited thin films have significant potential to clarify certain aspects of catalysts by eliminating parameters such as particle size dependence, metal-support interactions, and the presence of surface ligands.

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Article Synopsis
  • * A specific structure with 150 nm TiO, 8 nm TaO, and 150 nm copper nanocubes showed a faradaic efficiency of 24% under certain conditions when integrated into a photoelectrochemical flow reactor.
  • * Directly attaching copper nanocubes to just the TiO layer led to hydrogen production instead of CO reduction, and further studies indicate that the loss of selectivity is related to small copper particle redeposition without changes in the TiO's
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Introduction: A significant proportion of patients do not achieve seizure freedom despite treatment attempts with two different anti-seizure medications (ASMs). A subset may not truly have drug-resistant epilepsy ("pseudoresistant"), while rapid referral of patients with genuine drug-resistant epilepsy to surgery is mandated. This study was designed to evaluate a structured and intensive treatment course with the objective of promptly identifying cases of pseudoresistance and accelerating the time to referral to epilepsy surgery.

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Introduction: Evidence in child abuse cases can be scarce and is often centred around the child's testimony. However, child testimony varies with the child's development. Here, an overview of suspects, case decisions and court verdicts from a cohort of children is presented, stratified across children aged 0-3, 4-7, 8-11, and 12-15 years.

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Previous studies have identified δ-NiGa as a promising catalyst for the hydrogenation of CO to methanol at atmospheric pressure. Given its recent discovery, the current understanding of this catalyst is very limited. Additionally, the presence of multiple thermodynamically stable crystal phases in the Ni/Ga system complicates the experiments and their interpretation.

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Microelectromechanical system (MEMS) vertical cavity surface-emitting lasers (VCSELs) are the fastest coherently tunable lasers (nm/ns) due to their unique Doppler-assisted tuning mechanism. However, in standard electrostatic actuation, the response is highly nonlinear and large (>100 V) dynamic voltages are needed for MHz sweep rates. We present a bidirectional MEMS VCSEL as a solution to these challenges where static voltages can be used to enable substantially linear and amplified wavelength tuning with respect to the fast tuning (MEMS) voltage.

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Photocatalytic effects resulting in water splitting, reduction of carbon dioxide to fuels using solar energy, decomposition of organic compounds, and light-induced hydrophilicity observed on surfaces of various metal oxides (MOx), all rely on the same basic physical mechanisms, and have attracted considerable interest over the past decades. TiO and ZnO, two natively n-type doped wide bandgap semiconductors exhibit the effects mentioned above. In this study we propose a model for the photo-induced hydrophilicity in MOx films, and we test the model for TiO/Si and ZnO/Si heterojunctions.

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Background: Planting tested forest reproductive material is crucial to ensure the increased resilience of intensively managed productive stands for timber and wood product markets under climate change scenarios. Single-step Genomic Best Linear Unbiased Prediction (ssGBLUP) analysis is a cost-effective option for using genomic tools to enhance the accuracy of predicted breeding values and genetic parameter estimation in forest tree species. Here, we tested the efficiency of ssGBLUP in a tropical multipurpose tree species, Cordia africana, by partial population genotyping.

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Single nucleotide polymorphism (SNP) markers are powerful tools for investigating population structures, linkage analysis, and genome-wide association studies, as well as for breeding and population management. The availability of SNP markers has been limited to the most commercially important timber species, primarily due to the cost of genome sequencing required for SNP discovery. In this study, a combination of reference-based and reference-free approaches were used to identify SNPs in Nordmann fir (Abies nordmanniana), a species previously lacking genomic sequence information.

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This study sets out to investigate whether the 15-month nationwide COVID-19 lockdown in Denmark had an impact on the victim demographics, location of sexual assaults, and relationship between victim and perpetrator in the Western part of Denmark compared to the 15 months prior to the lockdown initiatives. This study is a retrospective study including a total of 596 cases. Cases were identified in the database of the Department of Forensic Medicine Aarhus, including cases labeled "rape," "attempted rape," and "later reported.

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Wavelength tunable lasers with narrow dynamic linewidths are essential in many applications, such as optical coherence tomography and LiDAR. In this letter, we present a 2D mirror design that provides large optical bandwidth and high reflection while being stiffer than 1D mirrors. Specifically, we investigate the effect of rounded corners of rectangles as they are transferred from the CAD to the wafer by lithography and etching.

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Objective: Visceral fat mass (VFM) is a risk factor for cardiovascular diseases, type 2 diabetes mellitus, and malignancy; however, normative data are limited. The aim of this study was to provide reference data for VFM from a large, apparently healthy Caucasian adult population.

Methods: Volunteers aged 20 to 93 years from the Copenhagen City Heart Study had a standardized whole-body dual-energy x-ray absorptiometry scan performed using the iDXA (GE Lunar).

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Off-axis electron holography was used to reveal remote doping in GaAs nanowires occurring duringannealing in a transmission electron microscope. Dynamic changes to the electrostatic potential caused by carbon dopant diffusion upon annealing were measured across GaAs nanowires with radial p-p+ core-shell junctions. Electrostatic potential profiles were extracted from holographic phase maps and built-in potentials () and depletion layer widths (DLWs) were estimated as function of temperature over 300-873 K.

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Multijunction solar cells in a tandem configuration could further lower the costs of electricity if crystalline Si (c-Si) is used as the bottom cell. However, for direct monolithic integration on c-Si, only a restricted number of top and bottom cell architectures are compatible, due to either epitaxy or high-temperature constraints, where the interface between subcells is subject to a trade-off between transmittance, electrical interconnection, and bottom cell degradation. Using polySi/SiO passivating contacts for Si, this degradation can be largely circumvented by tuning the polySi/SiO stacks to promote gettering of contaminants admitted into the Si bottom cell during the top cell synthesis.

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Electrical four-terminal sensing at (sub-)micrometer scales enables the characterization of key electromagnetic properties within the semiconductor industry, including materials' resistivity, Hall mobility/carrier density, and magnetoresistance. However, as devices' critical dimensions continue to shrink, significant over/underestimation of properties due to a by-product Joule heating of the probed volume becomes increasingly common. Here, we demonstrate how self-heating effects can be quantified and compensated for via 3ω signals to yield zero-current transfer resistance.

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Electrochemistry-mass spectrometry is a versatile and reliable tool to study the interfacial reaction rates of Faradaic processes with high temporal resolutions. However, the measured mass spectrometric signals typically do not directly correspond to the partial current density toward the analyte due to mass transport effects. Here, we introduce a mathematical framework, grounded on a mass transport model, to obtain a quantitative and truly dynamic partial current density from a measured mass spectrometer signal by means of deconvolution.

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Physical abuse is experienced by approximately 20% of children in Denmark. Healthcare workers issue less than 20% of all reports suspecting physical child abuse to responsible authorities. Insufficient knowledge and other barriers may partly explain this low percentage.

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Article Synopsis
  • The study aimed to evaluate the safety, feasibility, and patient satisfaction of a treatment course for epilepsy managed by specially trained nurses who could adjust medications.
  • Patients had regular contacts with nurses, resulting in improved management of anti-epileptic drugs (AED) and a significant decrease in seizure frequency, with 53.2% of patients reporting at least a 50% reduction in seizures.
  • Overall, the treatment approach proved to be safe, with high levels of patient satisfaction and no severe complications related to the intense care provided by the epilepsy nurses.
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The continuing miniaturization of optoelectronic devices, alongside the rise of electromagnetic metamaterials, poses an ongoing challenge to nanofabrication. With the increasing impracticality of quality control at a single-feature (-device) resolution, there is an increasing demand for array-based metrologies, where compliance to specifications can be monitored via signals arising from a multitude of features (devices). To this end, a square grid with quadratic sub-features is amongst the more common designs in nanotechnology (e.

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  • This paper investigates the DMSO/thiourea/chloride salt system for creating pure-sulfide CZTS thin-film solar cells in normal conditions.
  • It examines the impact of ink composition, mixing time, filtering, and thermal behavior of the ink, revealing that high pre-annealing temperatures can prevent undesirable film patterns but also lead to lower device efficiency.
  • Surprisingly, the study finds that a lower pre-annealing temperature yields the best device efficiency of 4.65%, indicating that larger grain sizes and a thicker CZTS/Mo interface layer contribute to better performance.
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Article Synopsis
  • The study focuses on the energy band alignment between CdS (n-type) and CuZnSnS (CZTS, p-type) solar cell materials, particularly how Ag alloying affects this interface and overall efficiency.
  • Ag alloying reduces defects in bulk CZTS, but its impact on the interface with CdS has not been well explored until now, using techniques like ultraviolet and X-ray photoelectron spectroscopy to analyze changes.
  • Results show significant shifts in electronic properties at the interface, revealing a cliff-like band alignment and indicating larger charge depletion widths with Ag alloying, which opens up new potential for future optoelectronic device applications.
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