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Imaging of branched chain amino acid metabolism in tumors with hyperpolarized 13C ketoisocaproate

Powerful analytical tools are vital for characterizing the complex molecular changes underlying oncogenesis and cancer treatment. This is particularly true, if information is to be collected in vivo by noninvasive approaches. In the recent past, hyperpolarized (13)C magnetic resonance (MR) spectroscopy has been employed to quickly collect detailed spectral information on the chemical fate of trace

Transmission schemes for Multiple Antenna Terminals in Real Massive MIMO systems

In massive MIMO performance evaluations it is often assumed that the terminal has a single antenna. The combination of multiple antennas in a terminal and massive MIMO precoding at the base station side can further improve overall system performance. We present measurement results for multi antenna terminals operating in different transmission schemes and how they perform under varying loading con

Magnetic resonance imaging of pH in vivo using hyperpolarized 13C-labelled bicarbonate

As alterations in tissue pH underlie many pathological processes, the capability to image tissue pH in the clinic could offer new ways of detecting disease and response to treatment. Dynamic nuclear polarization is an emerging technique for substantially increasing the sensitivity of magnetic resonance imaging experiments. Here we show that tissue pH can be imaged in vivo from the ratio of the sig

Co segregation of the m.1555A>G mutation in the MT-RNR1 gene and mutations in MT-ATP6 gene in a family with dilated mitochondrial cardiomyopathy and hearing loss : A whole mitochondrial genome screening

Mitochondrial disease refers to a heterogeneous group of disorders resulting in defective cellular energy production due to dysfunction of the mitochondrial respiratory chain, which is responsible for the generation of most cellular energy. Because cardiac muscles are one of the high energy demanding tissues, mitochondrial cardiomyopathies is one of the most frequent mitochondria disorders. Mitoch

Blood chemokine profile in untreated early rheumatoid arthritis : CXCL10 as a disease activity marker

Background: We have recently analyzed the profile of T-cell subtypes based on chemokine receptor expression in blood from untreated early rheumatoid arthritis (ueRA) patients compared to healthy controls (HC). Here, we compared the levels of the respective chemokines in blood plasma of ueRA patients with those of HC. We also studied the association of chemokine levels with the proportions of circu

Automatic procedure for generating symmetry adapted wavefunctions

Automatic detection of point groups as well as symmetrisation of molecular geometry and wavefunctions are useful tools in computational quantum chemistry. Algorithms for developing these tools as well as an implementation are presented. The symmetry detection algorithm is a clustering algorithm for symmetry invariant properties, combined with logical deduction of possible symmetry elements using t

LQG-optimal PI and PID control as benchmarks for event-based control

We formulate two simple benchmark problems for event-based control, where the optimal solutions in the continuous-time setting turn out to be ordinary PI and PID controllers. The benchmarks can be used to compare the performance of continuous-time, discrete-time, and various event-based controllers with regard to for instance disturbance attenuation, control effort, and average sampling or actuati

Parity, weight change, and maternal risk of cardiovascular events

Background High parity has been suggested to increase risk of maternal cardiovascular disease independent of body mass index measured after childbearing. Pregnancy is, however, associated with persistent weight gain and metabolic changes that, independent of parity, increase the risk of cardiovascular disease. It could therefore be questioned if high parity independently increases the risk of card

Multi-dimensional sinusoidal order estimation using angles between subspaces

Multi-dimensional harmonic retrieval (HR) in white noise is required in numerous applications such as channel estimation in wireless communications and imaging in multiple-input multiple-output radar. In this paper, we propose two R-dimensional (R -D) extensions of the subspace-based MUSIC model order selection scheme, for R≥2R≥2, to detect the number of multi-dimensional cisoids. The key idea in Multi-dimensional harmonic retrieval (HR) in white noise is required in numerous applications such as channel estimation in wireless communications and imaging in multiple-input multiple-output radar. In this paper, we propose two R-dimensional (R -D) extensions of the subspace-based MUSIC model order selection scheme, for R≥2R≥2, to detect the number of multi-dimensional cisoids. The key idea in

Interference Cancellation in Two-Channel Nuclear Quadrupole Resonance Measurements

Given its high specificity, the use of nuclear quadrupole resonance (NQR) spectroscopy allows for a reliable identification and quantification of substances containing quadrupolar nuclei, such as the 14N nucleus prevalent in many explosives, medicines, and narcotics. Regrettably, the measured signals are typically weak and suffers from interference signals often being several orders of magnitude s

Harmonic minimum mean squared error filters for multichannel speech enhancement

Many state-of-the-art multichannel speech enhancement methods rely on second-order statistics of the desired speech signal, the noise signal, or both. Estimation of those are difficult in practice, resulting in a practical performance that is typically much lower than their potential theoretical performance. We propose two multichannel enhancement techniques that instead rely on a model for voiced

Computationality efficient multi-pitch estimation using sparsity

In this work, we introduce a computationally efficient multi-pitch estimation algorithm making use of an approximative frequency domain reformulation of a recent block-sparse multi-pitch estimator. Different to most other pitch estimators, the proposed method does not require a prior knowledge of the number of sources present, nor the number of overtones of each such source. Evaluated on measured

Are there inequities in treatment of end-stage renal disease in Sweden? A longitudinal register-based study on socioeconomic status-related access to kidney transplantation

Socioeconomic status-related factors have been associated with access to kidney transplantation, yet few studies have investigated both individual income and education as determinates of access to kidney transplantation. Therefore, this study aims to explore the effects of both individual income and education on access to kidney transplantation, controlling for both medical and non-medical factors

Testing human skin and respiratory sensitizers—what is good enough?

Alternative methods for accurate in vitro assessment of skin and respiratory sensitizers are urgently needed. Sensitization is a complex biological process that cannot be evaluated accurately using single events or biomarkers, since the information content is too restricted in these measurements. On the contrary, if the tremendous information content harbored in DNA/mRNA could be mined, most compl

Understanding Occupation, Sick Leave, and Disability Pension Due to Knee and Hip Osteoarthritis From a Sex Perspective

Objective: To investigate the association between occupation and risk for sick leave or disability pension due to knee or hip osteoarthritis (OA) from a sex perspective. Methods: We conducted a population-based study including residents ages 40–70 years in the Skåne region, Sweden (2007) and working in the included job sectors (n = 165,179). We retrieved data on cause-specific sick leave and disab

Long-term stability of the HR 8799 planetary system without resonant lock

HR 8799 is a star accompanied by four massive planets on wide orbits. The observed planetary configuration has been shown to be unstable on a timescale much shorter than the estimated age of the system (~30 Myr) unless the planets are locked into mean motion resonances. This condition is characterised by small-amplitude libration of one or more resonant angles that stabilise the system by preventi

The origin of the eccentricity of the hot Jupiter in CI Tau

Following the recent discovery of the first radial velocity planet in a star still possessing a protoplanetary disc (CI Tau), we examine the origin of the planet's eccentricity (e ~0.3). We show through long time-scale (10^5 orbits) simulations that the planetary eccentricity can be pumped by the disc, even when its local surface density is well below the threshold previously derived from short ti

The unstable fate of the planet orbiting the A star in the HD 131399 triple stellar system

Validated planet candidates need not lie on long-term stable orbits, and instability triggered by post-main-sequence stellar evolution can generate architectures which transport rocky material to white dwarfs, hence polluting them. The giant planet HD 131399Ab orbits its parent A star at a projected separation of about 50-100 au. The host star, HD 131399A, is part of a hierarchical triple with HD