Nieveskrag5081
The paper presents a novel method to reduce the RF-induced heating of active implantable medical devices during MRI.
With the addition of an energy decoying and dissipating structure, RF energy can be redirected toward the dissipating rings through the decoying conductor. Three lead groups (45cm-50cm) and 4 (50cm-100cm) were studied in 1.5 Tesla MR systems by simulation and measurement, respectively. BTK inhibitor in vivo In vivo modeling was performed using human models to estimate the RF-induced heating of an active implantable medical device for spinal cord treatment.
In the simulation study, it was shown that the peak 1g-averaged specific absorption rate near the lead-tips can be reduced by 70% to 80% compared to those from the control leads. In the experimental measurements during a 2-min exposure test in a 1.5Telsa MR system, the temperature rises dropped from the original 18.3℃, 25.8℃, 8.1℃, and 16.1℃ (control leads 1-4) to 5.4℃, 6.9℃, 1.6℃, and 3.3℃ (leads 1-4 with the energy decoying and dissipation structure). The in vivo calculation results show that the maximum induced temperature rise among all cases can be substantially reduced (up to 80%) when the energy decoying and dissipating structures were used.
Our studies confirm the effectiveness of the novel technique for a variety of scanning scenarios. The results also indicate that the decoying conductor length, number of rings, and ring area must be carefully chosen and validated.
Our studies confirm the effectiveness of the novel technique for a variety of scanning scenarios. The results also indicate that the decoying conductor length, number of rings, and ring area must be carefully chosen and validated.
To report a quantitative time-of-flight (qTOF) MRA technique for simultaneous luminal and hemodynamic evaluation of the intracranial arteries.
Implemented using a thin overlapping slab 3D stack-of-stars based 3-echo FLASH readout, qTOF was tested in a flow phantom and for imaging the intracranial arteries of 10 human subjects at 3 Tesla. Display of the intracranial arteries with qTOF was compared to resolution-matched and scan time-matched standard Cartesian 3D time-of-flight (TOF) MRA, whereas quantification of mean blood flow velocity with qTOF, done using a computer vision-based inter-echo image analysis procedure, was compared to 3D phase contrast MRA. Arterial-to-background contrast-to-noise ratio was measured, and intraclass correlation coefficient was used to evaluate agreement of flow velocities.
For resolution-matched protocols of similar scan time, qTOF portrayed the intracranial arteries with good morphological correlation with standard Cartesian TOF, and both techniques provided superior conntly greater contrast-to-noise ratio efficiency than phase contrast and eliminates misregistration artifacts from oblique in-plane blood flow that occur with standard 3D TOF.The objective of this study was to investigate the accuracy of genomic prediction of body weight and eating quality traits in a numerically small sheep population (Dorper sheep). Prediction was based on a large multi-breed/admixed reference population and using (a) 50k or 500k single nucleotide polymorphism (SNP) genotypes, (b) imputed whole-genome sequencing data (~31 million), (c) selected SNPs from whole genome sequence data and (d) 50k SNP genotypes plus selected SNPs from whole-genome sequence data. Furthermore, the impact of using a breed-adjusted genomic relationship matrix on accuracy of genomic breeding value was assessed. The selection of genetic variants was based on an association study performed on imputed whole-genome sequence data in an independent population, which was chosen either randomly from the base population or according to higher genetic proximity to the target population. Genomic prediction was based on genomic best linear unbiased prediction (GBLUP), and the accuracy of genomic prediction was assessed according to the correlation between genomic breeding value and corrected phenotypes divided by the square root of trait heritability. The accuracy of genomic prediction was between 0.20 and 0.30 across different traits based on common 50k SNP genotypes, which improved on average by 0.06 (absolute value) on average based on using prioritized genetic markers from whole-genome sequence data. Using prioritized genetic markers from a genetically more related GWAS population resulted in slightly higher prediction accuracy (0.02 absolute value) compared to genetic markers derived from a random GWAS population. Using high-density SNP genotypes or imputed whole-genome sequence data in GBLUP showed almost no improvement in genomic prediction accuracy however, accounting for different marker allele frequencies in reference population according to a breed-adjusted GRM resulted to on average 0.024 (absolute value) increase in accuracy of genomic prediction.The intercondylar fossa ("intercondylar notch," IN) is a groove at the distal end of the femur, housing important stabilizing structures cruciate ligaments and meniscofemoral ligaments. As the risk for injury to these structures correlates with changes to the IN, exact knowledge of its morphology, possible physiological and pathological changes and different approaches for evaluating it are important. The divergent ways of assessing the IN and the corresponding measurement methods have led to various descriptions of its possible shapes. Ridges at the medial and lateral wall are considered clinically important because they can help with orientation during arthroscopy, whereas ridges at the osteochondral border could affect the risk of ligament injury. Changes related to aging and sex differences have been documented, further emphasizing the importance of individual assessment of the knee joint. Overall, it is of the utmost importance to remember the interactions between the osseous housing and the structures within.Epigenetic and molecular variation is a key approach for the improvement of plants. From in vitro tissue culture of Dendrocalamus farinosus; 30 plants were regenerated and after 2 years, the physiological, biochemical, and genomic studies were conducted. The results highlighted that for all phenotypic characteristics, the 30 regenerated plants were superior in comparison with the control (CK). From genetical analysis, a total of 97 bands were witnessed ranging between 212 bp and 2.2 kb. The results for OPU14 showed one additional specific band (723 bp) and one band (700 bp) were missing. The 10 plants were having genetic variability and can be termed as somaclones while the other plants have epigenetic variations. The cellulose and lignin analysis highlighted that somaclone No. 30 has the least cellulose content of 35%; while the somaclones No. 102 and No. 213 have the least 3.21% and 3.48% of lignin contents. Therefore, somaclones No. 30, No. 102, and No. 213 were selected for the histochemical localization. The lignin investigation revealed that somaclone No. 30 is greater while somaclones No. 102 and No. 213 were reduced in vascular bundles in comparison with the CK along with the high expression level of 4CL, C3H, C4H, COMT, and CCoAOMT1 genes.During quantitative real-time polymerase chain reaction (RT-qPCR) data analysis, the selection of optimal housekeeping gene is necessary to ensure the accuracy of results. It is noteworthy that housekeeping genes commonly used in adult studies may not be applicable for fetus. However, the stability analysis of housekeeping gene in fetal kidney has not been reported. This study intends to screen the applicable compound housekeeping genes in rat fetal kidney. In this study, eight housekeeping genes used in kidney studies based on literature reports (GAPDH, ACTB, 18S, HPRT, YWHAZ, HMBS, PPIA, and TBP) were selected as the research object. Their expression levels in the rat fetal kidney in physiological condition and the intrauterine growth retardation (IUGR) model induced by prenatal dexamethasone exposure (PDE) (0.2 mg/kg·day from gestation Days 9 to 20) was measured. Furthermore, these eight housekeeping genes were used to conduct relative quantitative analysis of nephrin expression in the fetal kidney in PDE-induced IUGR model, to compare the influence of choosing different housekeeping gene on data analysis of nephrin expression and to verify the reliability of selected compound housekeeping genes. In this study, stable housekeeping genes of fetal kidney tissues in PDE-induced IUGR model were identified ACTB, GAPDH, TBP, and HMBS for males; ACTB, YWHAZ, and GAPDH for females. Besides, our results suggest that ACTB + GAPDH were the best compound housekeeping genes for normalization analysis in male fetal kidney studies, and ACTB + YWHAZ in females. This study will provide an experimental evidence basis for the selection of housekeeping genes in the RT-qPCR experiment in renal development toxicology-related models.
Ultrahigh field MRS has improved characterization of the neurochemical profile. To compare results obtained at 9.4T to those from lower field strengths, it is of interest to quantify the concentrations of metabolites measured. Thus, measuring T
-relaxation times is necessary to correct for T
-weighting that occurs in acquisitions for single-voxel spectroscopy and spectroscopic imaging. A macromolecule (MM) simulation model was developed to fit MM contributions to the short TE inversion series used to measure T
-relaxation times.
An inversion series with seven time points was acquired with metabolite-cycled STEAM to estimate T
-relaxation times of metabolites. A short TE was employed in this study to retain signals from metabolites with short T
-relaxation times and J-couplings. The underlying macromolecule spectrum was corrected by developing a sequence-specific, relaxation-corrected simulated MM model. Quantification of metabolite peaks was performed using internal water referencing and relaxatom GM- and WM-rich voxels are reported.We propose a Pandemic Risk Perception Scale. Our scale comprises two constructs, Dread Risk and Personal Exposure, divided into five dimensions Infection Risk, Emotional Health Risk, Health System Risk,Financial Risk, and Alimentary Risk. Using multidimensional item response theory, confirmatory factor analysis, and structural equation modeling on two samples of respondents, our results show that Alimentary Risk, Health System Risk, and Emotional Health Risk are the main dimensions of risk perception for the COVID-19 pandemic. Furthermore, Infection Risk has a minor impact on the pandemic's risk perception, suggesting the presence of different dynamics between personal and general risk perceptions for the COVID-19 pandemic.The laterodorsal tegmentum (LDT) is a brainstem nucleus classically involved in REM sleep and attention, and that has recently been associated with reward-related behaviors, as it controls the activity of ventral tegmental area (VTA) dopaminergic neurons, modulating dopamine release in the nucleus accumbens. To further understand the role of LDT-VTA inputs in reinforcement, we optogenetically manipulated these inputs during different behavioral paradigms in male rats. We found that in a two-choice instrumental task, optical activation of LDT-VTA projections shifts and amplifies preference to the laser-paired reward in comparison to an otherwise equal reward; the opposite was observed with inhibition experiments. In a progressive ratio task, LDT-VTA activation boosts motivation, that is, enhances the willingness to work to get the reward associated with LDT-VTA stimulation; and the reverse occurs when inhibiting these inputs. Animals abolished preference if the reward was omitted, suggesting that LDT-VTA stimulation adds/decreases value to the stimulation-paired reward.