57 research outputs found
In vivo MRI of the human finger at 7 T
PURPOSE: To demonstrate a dedicated setup for ultrahigh resolution MR imaging of the human finger in vivo. METHODS: A radiofrequency coil was designed for optimized signal homogeneity and sensitivity in the finger at ultrahigh magnetic field strength (7 T), providing high measurement sensitivity. Imaging sequences (2D turbo-spin echo (TSE) and 3D magnetization-prepared rapid acquisition gradient echo (MPRAGE)) were adapted for high spatial resolution and good contrast of different tissues in the finger, while keeping acquisition time below 10 minutes. Data was postprocessed to display finger structures in three dimensions. RESULTS: 3D MPRAGE data with isotropic resolution of 200 µm, along with 2D TSE images with in-plane resolutions of 58 × 78 µm2 and 100 × 97 µm2 , allowed clear identification of various anatomical features such as bone and bone marrow, tendons and annular ligaments, cartilage, arteries and veins, nerves, and Pacinian corpuscles. CONCLUSION: Using this dedicated finger coil at 7 T, together with adapted acquisition sequences, it is possible to depict the internal structures of the human finger in vivo within patient-compatible measurement time. It may serve as a tool for diagnosis and treatment monitoring in pathologies ranging from inflammatory or erosive joint diseases to injuries of tendons and ligaments to nervous or vascular disorders in the finger. Magn Reson Med 79:588-592, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited
The Energy Spectrum of TeV Gamma-Rays from the Crab Nebula as measured by the HEGRA system of imaging air Cherenkov telescopes
The Crab Nebula has been observed by the HEGRA (High-Energy Gamma-Ray
Astronomy) stereoscopic system of imaging air Cherenkov telescopes (IACTs) for
a total of about 200 hrs during two observational campaigns: from September
1997 to March 1998 and from August 1998 to April 1999. The recent detailed
studies of system performance give an energy threshold and an energy resolution
for gamma-rays of 500 GeV and ~ 18%, respectively. The Crab energy spectrum was
measured with the HEGRA IACT system in a very broad energy range up to 20 TeV,
using observations at zenith angles up to 65 degrees. The Crab data can be
fitted in the energy range from 1 to 20 TeV by a simple power-law, which yields
dJg/dE = (2.79+/-0.02 +/- 0.5) 10^{-7} E^{-2.59 +/- 0.03 +/- 0.05}, ph m^{-2}
s^{-1} TeV^{-1} The Crab Nebula energy spectrum, as measured with the HEGRA
IACT system, agrees within 15% in the absolute scale and within 0.1 units in
the power law index with the latest measurements by the Whipple, CANGAROO and
CAT groups, consistent within the statistical and systematic errors quoted by
the experiments. The pure power-law spectrum of TeV gamma-rays from the Crab
Nebula constrains the physics parameters of the nebula environment as well as
the models of photon emission.Comment: to appear in ApJ, 29 pages, 6 figure
Exploring the success factors of hybrid micro-enterprises
This research explores hybrid micro-entrepreneurs’ founding motivations and the transformation of those motivations into visions of success, by applying multiple criteria decision analysis (MCDA). We find that entrepreneurs of hybrid micro-enterprises are driven mostly by noneconomic goals and that those influence their vision of success. The success framework consists of seven indicators (training, professional development, marketing, management, external factors, infrastructures, and organizational aspects). Human capital is perceived as the most important for success – translating the professional motivations for founding. Reversely, external factors, which are usually considered crucial to attain legitimacy, are perceived the least important factors. Given the findings, are hybrid micro-entrepreneurs ready to succeed?info:eu-repo/semantics/publishedVersio
Perspectives and attitudes of breastfeeding women using herbal galactagogues during breastfeeding: a qualitative study
Some herbal galactagogues have gained reputation and recognition by the public and health professionals as alternative approaches to increase breast milk supply. This study explores the perspectives and attitudes of breastfeeding women towards the use of herbal galactagogues while breastfeeding, their experiences, and why and how they have chosen an alternative option over conventional treatments to enhance breastfeeding performance. This exploratory research was conducted through in-depth semi-structured interviews with women living in Perth, Western Australia, who were using one or more herbal galactagogues during breastfeeding. Purposeful and subsequent snowball sampling methods were employed to recruit participants. All interviews, facilitated by an interview guide, were audio-recorded, then transcribed verbatim. Thematic analysis was used to analyse qualitative data to construct themes and subthemes.The perspectives and attitudes of the 20 participants are classified under three main headings: i) use of herbal medicines during breastfeeding, ii) available herbal medicines resources, and iii) level of breastfeeding support received. Throughout the interviews, participants described how their perseverance and determination to breastfeed, as well as concerns over breastfed infants’ safety with conventional treatments, influenced their choice of therapy. A sense of self-efficacy and autonomy over their own health needs was seen as influential to their confidence level, supported self-empowerment and provided reassurance throughout the breastfeeding journey. There was also a desire for more evidence-based information and expectations of health professionals to provide credible and reliable information regarding the use of herbal medicines during breastfeeding. This study has enhanced our understanding of the perspectives and attitudes of breastfeeding women towards the use of herbal medicines, in particular galactagogues, while breastfeeding. The positive attitudes of breastfeeding women identified in this study highlight the need for further research into evaluating the safety and efficacy of commonly used herbal galactagogues, whilst the negative views on breastfeeding education should be taken into consideration when implementing or improving breastfeeding-related health policies
Homeopathic medical practice for anxiety and depression in primary care: the EPI3 cohort study
Administration of a standardized plasma-protein solution (Biseko®) in high-risk patients with systemic inflammatory response syndrome: influence on cytokine levels and survival
Low-Molecular-Weight Heparin Inhibits Neutrophil Transmigration through Endothelial Cell Monolayers
NMR in Biomedicine / Dynamic multivoxel-localized 31P MRS during plantar flexion exercise with variable knee angle
Exercise studies investigating the metabolic response of calf muscles using 31P MRS are usually performed with a single knee angle. However, during natural movement, the distribution of workload between the main contributors to force, gastrocnemius and soleus is influenced by the knee angle. Hence, it is of interest to measure the respective metabolic response of these muscles to exercise as a function of knee angle using localized spectroscopy.
Timeresolved multivoxel 31P MRS at 7 T was performed simultaneously in gastrocnemius medialis and soleus during rest, plantar flexion exercise and recovery in 12 healthy volunteers. This experiment was conducted with four different knee angles.
PCr depletions correlated negatively with knee angle in gastrocnemius medialis, decreasing from 7914 % (extended leg) to 3523 %(40), and positively in soleus, increasing from 2021 % to 3625 %; differences were significant. Linear correlations were found between knee angle and endexercise PCr depletions in gastrocnemius medialis (R2=0.8) and soleus (R2=0.53). PCr recovery times and endexercise pH changes that correlated with PCr depletion were consistent with the literature in gastrocnemius medialis and differences between knee angles were significant. These effects were less pronounced in soleus and not significant for comparable PCr depletions. Maximum oxidative capacity calculated for all knee angles was in excellent agreement with the literature and showed no significant changes between different knee angles.
In conclusion, these findings confirm that plantar flexion exercise with a straight leg is a suitable paradigm, when data are acquired from gastrocnemius only (using either localized MRS or small surface coils), and that activation of soleus requires the knee to be flexed. The present study comprises a systematic investigation of the effects of the knee angle on metabolic parameters, measured with dynamic multivoxel 31P MRS during muscle exercise and recovery, and the findings should be used in future study design.(VLID)340101
Inhibitory Effect of Omeprazole on Transmigration of Leukocytes through Endothelial Cell Monolayers and Leukocyte Adhesion
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