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Aging of the hematopoietic stem cell compartment is believed to contribute to the onset of a variety of age-dependent blood cell pathophysiologies. Mechanistic drivers of hematopoietic stem cell (HSC) aging include DNA damage accumulation and induction of tumor suppressor pathways that combine to reduce the regenerative capacity of aged HSCs. Such mechanisms do not however account for the change i
In this report we explore the structural and optical properties of GaAs/AlGaAs heterostructure nanowires grown by metalorganic vapour phase epitaxy using gold seed-particles. The optical studies were done by low-temperature cathodoluminescence (CL) in a scanning electron microscope (SEM). We perform a systematic investigation of how the nanowire growth-temperature affects the total photon emission
The shelterin complex protects chromosomal ends by regulating how the telomerase complex interacts with telomeres. Following the recent finding in familial melanoma of inactivating germline mutations in POT1, encoding a member of the shelterin complex, we searched for mutations in the other five components of the shelterin complex in melanoma families.
Because of a low prevalence of severe carotid stenosis in the general population, screening for presence of asymptomatic carotid artery stenosis (ACAS) is not warranted. Possibly, for certain subgroups, screening is worthwhile. The present study aims to develop prediction rules for the presence of ACAS (>50% and >70%).
We have investigated the growth of self-catalyzed GaAs/GaAsxSb1-x core-shell nanowires directly on Si(111) substrates by molecular beam epitaxy. The compositions of the GaAsxSb1-x shells are tuned in a wide range where the Sb-content is varied from 10 to similar to 70%, covering the miscibility gap. In addition, the GaAsxSb1-x shells are grown on both zinc blende (ZB) and wurtzite (WZ) crystal str
Carcinogenic aromatic amines derived from hair dyes have recently received new attention. One of these is ortho (o)-toluidine, which is classified as carcinogenic to humans.
Microchip-based free flow acoustophoresis (FFA) in combination with two-dimensional cell prefocusing enables concurrent multiple target outlet fractionation of leukocytes into subpopulations (lymphocytes, monocytes, and granulocytes); we report on this method here. We also observed significantly increased accuracy in size-based fractionation of microbeads as compared to previously presented FFA mu
A thorough understanding of how proteins induce nanoparticle (NP) aggregation is crucial when designing in vitro and in vivo assays and interpreting experimental results. This knowledge is also crucial when developing nano-applications and formulation for drug delivery systems. In this study, we found that extraction of immunoglobulin G (IgG) from cow serum results in lower polystyrene NPs aggrega
Semiconductor nanowires composed of III-V materials have enormous potential to add new functionality to electronics and optical applications. However, integration of these promising structures into applications is severely limited by the current near-universal reliance on gold nanoparticles as seeds for nanowire fabrication. Although highly controlled fabrication is achieved, this metal is entirel
We present cathodoluminescence data of nanowires (NWs) grown using size-selected gold particles as seeds. The NWs have a GaAs core with a diameter of 50 nm and a length of several mu m. The NWs in this study were generally covered with a shell of AlGaAs. With increasing growth temperature, the emission intensity increases significantly. From a variety of growth conditions, we conclude that the exp
Mn-doped GaAs nanowires were grown in the self-catalytic growth mode on the oxidized Si(100) surface by molecular beam epitaxy and characterized by scanning and transmission electron microscopy, Raman scattering, photoluminescence, cathodoluminescence, and electron transport measurements. The transmission electron microscopy studies evidenced the substantial accumulation of Mn inside the catalyzin
In semiconductor heterostructures with a type II band alignment, such as GaSb-InAs, conduction can be tuned from electron- to hole-dominated using an electrostatic gate. However, traditional conductance measurements give no direct information on the carrier type, and thus limit the ability to distinguish transport effects originating from the two materials. Here, we employ thermovoltage measuremen
Epidemiological studies suggest that low levels of vitamin D (25OHD) constitute a risk factor for more aggressive prostate cancer. We examined the relationship between pre-diagnostic serum levels of vitamin D, parathyroid hormone (PTH), and calcium and risk of prostate cancer according to tumor aggressiveness.
Enrichment of rare cells from peripheral blood has emerged as a means to enable noninvasive diagnostics and development of personalized drugs, commonly associated with a prerequisite to concentrate the enriched rare cell population prior to molecular analysis or culture. However, common concentration by centrifugation has important limitations when processing low cell numbers. Here, we report on a
Crystal phase control in single III-V semiconductor nanowires has emerged recently as an important challenge and possible complement to conventional bandgap engineering in single material systems. Here we investigate a supply interruption method for precise crystal phase control in single nanowires. The nanowires are grown by metalorganic vapor phase epitaxy using gold particles as seeds and are a
Doping mechanisms of Mn in GaAs nanowires (NWs) that have been grown self-catalytically at 600 degrees C by molecular beam epitaxy (MBE) are investigated using advanced electron microscopy techniques and atom probe tomography, Mn is found to be incorporated primarily in the form of non-magnetic tetragonal Ga0.82Mn0.18 nanocrystals in Ga catalyst droplets at the ends of the NWs, while trace amounts
Here we demonstrate the existence of two distinct regimes for tuning crystal structure in GaAs nanowires from zinc blende to wurtzite using a single process parameter: V/III-ratio, or variation of the group V precursor flow. Extensive previous studies have shown that crystal structure is sensitive to V/III-ratio, and even that it is possible to change structure entirely using this single parameter
The magnitude and Impact of the parasitic capacitances in a vertical InAs nanowire transistor consisting of a matrix of nanowires is evaluated A simple transistor model is fitted to experimental I-V characteristics and the influence of the parasitic components on the transistor performance for different structures is investigated Simulations of the S parameters indicate an intrinsic f(T) of about
Optical upconversion via a multiphoton absorption process converts incoherent low-energy photons to shorter wavelengths. In this contribution, we report a solid-state thin film for infrared-to-visible upconversion composed of plasmonic/TiO2 interfaces. When excited at λ = 800 nm, three photons are absorbed, leading to the excitation of TiO2 trap states into an emissive state in the visible domain.
In this chapter we propose a novel ethical approach to city branding based on a relational understanding of vulnerability. We rethink the prevailing ethics of competition and competitiveness in the field by demonstrating its limitations for contributing positively to urban sustainable development. An ethics of vulnerability approach is outlined based on principles of performativity, interdependenc
