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The application of Ca isotopic analysis in biomedical studies has great potential to identify changes in Ca metabolism and bone metabolism. Reliable measurement of Ca isotope-amount ratios is challenging considering limited Ca amounts and significant procedural blank levels. In this study, Ca purification was performed using the DGA Resin, optimized for low procedural blanks and separation of Ca from matrix elements and isobaric interferences (Na, Mg, K, Ti, Fe, Ba), while maintaining quasi-quantitative recoveries which are sufficient since a 42Ca–48Ca double-spike (DS) was applied. Ca isotopic analysis was performed using multicollector thermal ionization mass spectrometry (MC TIMS). The obtained procedural Ca blank of ≤10 ng enables processing of limited Ca amounts down to 670 ng. Data reduction of the measured Ca isotope-amount ratios was performed using an in-house developed software solving the DS algorithm. Data quality was improved by extension of equilibration time of the sample-DS mixture and implementation of a normalization strategy for raw isotopic data. The reported δ(44Ca/40Ca)NIST SRM 915a of NIST SRM 915a processed as a sample was found to be 0.01 ‰ ± 0.08 ‰ (2 SD, n = 15). Ca isotope-amount ratios of the reference material NIST SRM 1400 (bone ash), NIST SRM 1486 (bone meal), GBW07601 (human hair), and IAPSO (seawater) were in good agreement within uncertainty with literature data. Novel data on additional reference materials for biological tissues (hair) is presented, which might indicate a potential fractionation of Ca incorporated into hair tissue when compared to the blood pool. [ABSTRACT FROM AUTHOR]

The ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase. [ABSTRACT FROM AUTHOR]

The Advanced Small Analyzer for Neutrals (ASAN) is a compact mass resolving energetic neutral atom analyzer flown on the Yutu-2 rover of the Chinese Chang’E-4 mission to the Moon. ASAN measures energetic neutral atoms in the energy range from 10 eV to 10 keV with typically 30% energy resolution. The field-of-view is a single angular pixel of 37° × 30° pointing at lunar surface. Energetic neutral atoms enter the instrument through a charge particle deflection system and are then ionized on a diamond-like carbon conversion surface. Positive ions from the conversion surface are energy analyzed using an electrostatic analyzer and their velocity is subsequently determined in a time-of-flight section using ceramic channel electron multipliers as detectors. The obtained mass resolution m/ Δ m is about 2, comfortably separating neutral hydrogen, helium, and the oxygen-group (≥16 amu). A full energy spectrum for energetic neutral atoms is obtained in 3 seconds. Switching the charged particle deflection system off, ASAN also directly measures positive ions with similar performance as for energetic neutral atoms. Including electronics the instrument weighs 970 g and consumes 3.4 W. [ABSTRACT FROM AUTHOR]

A Correction to this paper has been published: https://doi.org/10.1007/s11214-021-00809-8 [ABSTRACT FROM AUTHOR]

We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (<100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe's fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. All in all, it is demonstrated how the descent probe has the potential to provide a high science return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe for the former Europa-Jupiter System Mission of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission. [ABSTRACT FROM AUTHOR]

The isotopic compositions of molybdenum in six uranium-rich samples from the Oklo Zone 9 natural reactor were accurately measured by thermal ionization mass spectrometry. The samples were subjected to an ion exchange separation process that removed the isobaric elements zirconium and ruthenium, with high efficiency and a low blank. Molybdenum possesses seven isotopes of which Mo are unaffected by the fission process, enabling the raw data to be corrected for isotope fractionation by normalising to Mo/Mo, and to use Mo to correct for the primordial component in each of the fission-produced isotopes. This enables the relative fission yields of Mo to be calculated from the isotopic composition measurements, to give cumulative fission yields of 1:0.941:0.936:1.025 for Mo, respectively. These data demonstrate that the most important nuclear process involved in reactor Zone 9 was the thermal neutron fission of U. The consistency of the relative cumulative fission yields of all six samples from different locations in the reactor, implies that Mo is a mobile element in the uraninite comprising Zone 9, and that a significant fraction of molybdenum was mobilized within the reactor zone and probably escaped from Zone 9, a conclusion in agreement with earlier published work. [ABSTRACT FROM AUTHOR]

Arthroscopy of the elbow continues to gain in importance. The correct indication plays a key role in the success of treatment. In addition to common surgery of the cartilage and synovia, the indication for arthroscopy of the elbow can be widened in the hand of an experienced operator including instabilities and functional impairments. Extending the indication of the treatment to elbow fractures currently remains the exception. [ABSTRACT FROM AUTHOR]

Diagnostic and surgical arthroscopy of the shoulder joint has gained in importance in recent years in trauma surgery, replacing open surgery in many cases of soft tissue lesions. Compared with other diagnostic methods, arthroscopy offers the broadest and most reliable information on shoulder lesions. Dislocation of the glenoid labrum after traumatic shoulder luxation, lesions of the biceps tendon, rotator-cuff tear or subacromial impingement syndrome all represent indications for arthroscopy. Due to the further development of instruments and special anchoring materials, surgical techniques are becoming faster and increasingly effective, while at the same time the complication rate decreases. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the accuracy of high-pitch delayed enhancement (DE) CT for the assessment of myocardial viability with MRI as the reference standard.Methods: Twenty-four patients (mean age 66.9 ± 9.2 years) with coronary artery disease underwent DE imaging with 128-slice dual-source CT (prospective electrocardiography (ECG)-triggering) and MRI at 1.5 T. Two observers assessed DE transmurality per segment, and measured signal intensity (MRI) or attenuation (CT) in infarcted and healthy myocardium and noise in the left ventricular blood pool for calculating contrast-to-noise ratios (CNR).Results: 75/408 (18.4%) segments in 18/24 patients (75.0%) showed DE in MRI, of which 28 segments in 10/24 (41.7%) patients were non-viable (scar tissue transmurality >50%). Sensitivity, specificity and accuracy of CT for diagnosis of non-viability were 60.7%, 96.8% and 94.4% per segment, and 90.0%, 92.9% and 91.7% per patient. CNR was significantly higher in MR (7.4 ± 3.0 vs. 4.6 ± 1.5; p = 0.018), and image noise significantly lower (11.6 ± 5.7 vs.15.0 ± 4.5; p = 0.019). Radiation dose of DECT was 0.89 ± 0.07 mSv.Conclusions: CTDE imaging in the high-pitch mode enables myocardial viability assessment at a low radiation dose and good accuracy compared with MR, although associated with a lower CNR and higher noise. [ABSTRACT FROM AUTHOR]

Purpose: To describe prospective ECG-triggered dual-source CT dual-step pulsing (pECG(dual_step)) for evaluation of coronary arteries and cardiac function.Methods: Fifty-one consecutive patients pre- or post-cardiovascular surgery were examined with adaptive sequential tube current modulated (pECG(dual-step)) 128-slice dual-source CT without heart rate control (main padding window: 40% RR interval >65 bpm/70% RR interval <65 bpm). Image quality of coronary arteries was graded (4-point scale), and cardiac function was evaluated.Results: Mean HR was 68 bpm. Thirty-seven patients were in stable sinus rhythm (SR); 14 had arrhythmia. Image quality of coronary arteries was diagnostic in 804/816 (98%) of segments. The number of non-diagnostic segments was higher in patients with arrhythmia as compared to those in SR (4% vs. 0.5%; p = 0.01), and there were fewer segments with excellent image quality (79% vs. 94%; p < 0.001) and more segments with impaired image quality (p < 0.001 and p = 0.002). Global and regional LV function could be evaluated in 41 (80%) and 47 (92%) patients, and valvular function in 48 (94%). In 11/14 of patients with arrhythmia, the second step switched to full mAs, increasing radiation exposure to 8.6 mAs (p < 0.001). The average radiation dose was 3.8 mSv (range, 1.7-7.9) in patients in SR.Conclusion: pECG(dual-step)128-slice DSCT is feasible for the evaluation of coronary arteries and cardiac function without heart rate control in patients in stable sinus rhythm at a low radiation dose. [ABSTRACT FROM AUTHOR]

Human gait is a complex process in the central nervous system that results from the integrity of various mechanisms, including different cortical and subcortical structures. In the present study, we investigated cortical activity during lower limb movement using EEG. Assisted by a dynamic tilt table, all subjects performed standardized stepping movements in an upright position. Source localization of the movement-related potential in relation to spontaneous EEG showed activity in brain regions classically associated with human gait such as the primary motor cortex, the premotor cortex, the supplementary motor cortex, the cingulate cortex, the primary somatosensory cortex and the somatosensory association cortex. Further, we observed a task-related power decrease in the alpha and beta frequency band at electrodes overlying the leg motor area. A temporal activation and deactivation of the involved brain regions as well as the chronological sequence of the movement-related potential could be mapped to specific phases of the gait-like leg movement. We showed that most cortical capacity is needed for changing the direction between the flexion and extension phase. An enhanced understanding of the human gait will provide a basis to improve applications in the field of neurorehabilitation and brain–computer interfaces. [ABSTRACT FROM AUTHOR]

The Interstellar Boundary Explorer (IBEX) mission will provide maps of energetic neutral atoms (ENAs) originating from the boundary region of our heliosphere. On IBEX there are two sensors, IBEX-Lo and IBEX-Hi, covering the energy ranges from 10 to 2000 eV and from 300 to 6000 eV, respectively. The expected ENA signals at 1 AU are low, therefore both sensors feature large geometric factors. In addition, special attention has to be paid to the various sources of background that may interfere with our measurement. Because IBEX orbits the Earth, ion, electron, and ENA populations of the Earth’s magnetosphere are prime background sources. Another potential background source is the magnetosheath and the solar wind plasma when the spacecraft is outside the magnetosphere. UV light from the night sky and the geocorona have to be considered as background sources as well. Finally background sources within each of the sensors must be examined. [ABSTRACT FROM AUTHOR]

The relative cumulative fission yields of 95,97,98,100Mo produced by spontaneous fission of 238U contained in Archaean zircons, were measured by sensitive thermal ionization mass spectrometry (TIMS). The relative yields for 95,97,98,100Mo are 0.58 : 1.08 : 1.04 : 1.0, respectively. Combined with mass spectrometrically-determined 99,101,102,104Ru fission yields,1 the mass distribution from 95£A£104 can be delineated. Assuming an “absolute' fission yield of 6.1±0.4% for the cumulative fission yield at mass 97, it is possible to express the Mo and Ru relative spontaneous fission yields for 238U as “absolute' values. There is no evidence for a significant isotope anomaly at mass 98. [ABSTRACT FROM AUTHOR]

Isotope dilution mass spectrometry is an ideal analytical technique to measure the elemental abundance of Mo in C1 carbonaceous chondrites and the metallic and troilite phases of iron meteorites. The mean abundance of Mo in two C1 meteorites is 0.909 ± 0.040 μg/g which corresponds to a value of 2.55 atoms Mo with respect to Si equal to 106 atoms, which is identical to the currently accepted solar system abundance. The partitioning of Mo between the metallic and sulfide phases in the Mundrabilla iron meteorite was found to be 6.0 ± 0.2 μg/g and 8.6 ± 0.3 μg/g, respectively. A new, precise Mo concentration of 1.54 ± 0.04 μg/g for the Geochemical Reference Standard BCR-1 is also reported. [ABSTRACT FROM AUTHOR]

This paper demonstrates the possibilities in transfering HPLC methods from porous to non-porous stationary phases. The procedures are transferred from 125 or 250 mm columns packed with porous stationary phases to 33 mm columns packed with non-porous particles. It is demonstrated that fast HPLC using non-porous columns reduces analysis times by a factor four to eight. Precision is comparable to HPLC with porous stationary phases. The costs for HPLC with porous and with nonporous packing materials are similar. The implementation of these fast HPLC columns is easy because standard equipment can be used. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Oto-rhino-laryngology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Oto-rhino-laryngology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archives of Oto-rhino-laryngology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

5-Hydroxypyrazine-2-carboxylic acid, a versatile building block for the synthesis of new antituberculous agents, was prepared by whole-cell biotransformation from 2-cyanopyrazine via pyrazinecarboxylic acid using Agrobacterium sp. DSM 6336. By developing a fermentation process for this two-enzyme-step bioconversion, a product concentration of 286 mM (40 g/l) was obtained. After the isolation method had been optimized the total yield was 80%. [ABSTRACT FROM AUTHOR]