Abstract
Sodium molybdate crystals are excellent scintillating target material that can be used to investigate the neutrinoless double beta decay of
100
Mo.
Because this material contains Na nuclei, ...it could also be used to clarify the contribution of Na in the controversial claim of dark matter observation by the DAMA/LIBRA experiment.
Recent developments have allowed the growth of sodium molybdate crystals of several hundred grams, which makes it possible to build large scale experiments.
Therefore, a cryogenic calorimeter with a crystal of significant mass, which can exploit the excellent energy resolution from thermal signals and particle identification using the scintillation signals,
is highly desired. We have developed a cryogenic calorimeter with a cylindrical sodium molybdate
crystal of 178 g with dimensions of 4 cm (height) × 4 cm (diameter) coupled to a metallic magnetic calorimeter (MMC).
The detector was also equipped with a light detector with a thin Ge absorber to detect scintillation signals.
The detector test measurements showed excellent energy resolution and particle discrimination using dual detection of heat and light signals,
and thus demonstrate that the crystal is a promising tool for searching for rare phenomena events.
Details of the detector development with the massive sodium molybdate crystal are discussed in this paper along with the performance results from test measurements.
With recent advances in magnetic resonance image-guided radiation therapy (MR-IGRT), Fricke gel dosimetry has demonstrated value for its ability to measure three-dimensional dose distributions in the ...presence of a strong magnetic field. This strong magnetic field causes hot and cold spots in dose distributions at the interfaces of lung and normal tissue due to a phenomenon known as the electron return effect (ERE). In this paper, we report the development of lung-equivalent gel dosimeters to better measure dose to lung tissue caused by the ERE. Small polystyrene beads of variable sizes were mixed into Fricke xylenol orange gelatin (FXG) and ferrous oxide xylenol orange (FOX) gels. Lung-equivalence was confirmed by measuring the average CT number of each gel. The effects of gel type, bead size, and voxel size on uniformity and signal intensity were investigated. The smallest beads ( < 1 mm) exhibited the best uniformity, with values comparable to conventional gel with 2 mm voxels. Signal intensity followed an inverse relationship with uniformity, but FXG low-density dosimeters generated enough signal to produce acceptable quality images. The spin-lattice relaxation rate (R1 = 1/T1) increased with dose, which enabled us to measure dose to both soft tissue and lung due to the ERE using a phantom simulating the soft tissue-lung interface.
Two types of Neoproterozoic metabasites occur together with regionally intruded arc-related Neoproterozoic granitoids (ca. 850–830 Ma) in the Hongseong area, southwestern Gyeonggi Massif, South ...Korea, which is the extension of the Dabie–Sulu collision belt in China. The first type of metabasite (the Bibong and Baekdong metabasites) is a MORB-like back-arc basin basalt or gabbro formed at ca. 890–860 Ma. The Bibong and Baekdong metabasites may have formed during back-arc opening by diapiric upwelling of deep asthenospheric mantle which was metasomatized by large ion lithophile element (LILE) enriched melt or fluid derived from the subducted slab and/or subducted sediment beneath the arc axis. The second type of metabasite (the Gwangcheon metabasite) formed in a plume-related intra-continental rift setting at 763.5
±
18.3 Ma and is geochemically similar to oceanic island basalt (OIB). These data indicate a transition in tectonic setting in the Hongseong area from arc to intra-continental rift between ca. 830 and 760 Ma. This transition is well correlated to the Neoproterozoic transition from arc to intra-continental rift tectonic setting at the margin of the Yangtze Craton and corresponds to the amalgamation and breakup of Rodinia Supercontinent.
Dynamical properties of argon plasma jet at atmospheric pressure driven by microwave pulses with high repetition rate and fast rise time are investigated using time-resolved optical emission ...measurements in combination with fast imaging. Spectroscopic measurements reveal an emission burst at the pulse rise including electron continuum emission, hydroxyl molecular lines, and a large overshoot of argon atomic lines. The latter can be interpreted as a transient increase in electron temperature supported by a numerical simulation. At the pulse off, an afterglow burst of argon lines is observed with a time scale much faster than the conventional afterglow in low pressure discharges. The afterglow burst indicates dissociative recombination of argon dimer ions and generation of excited argon species, implying that the afterglow phenomenon can be used to optimize the pulse operation. Compared to continuous wave operation, the time-averaged emissions of Ar* and OH radical are enhanced by about 60% and 30%, respectively, in the pulsed microwave operation, suggesting more efficient generation of reactive species.
Unenhanced CT scanning can reliably characterize incidentally detected adrenal masses when observers use density measurements of the adrenal gland. However, controversy exists as to the optimal ...density threshold required to differentiate benign from malignant lesions. This study attempts to establish a consensus by performing a pooled analysis of data found in the CT literature.
Ten CT reports were analyzed, from which individual adrenal lesion density measurements were obtained for 495 adrenal lesions (272 benign lesions and 223 malignant lesions). Threshold analysis generated a range of sensitivities and specificities for lesion characterization at different density thresholds.
Sensitivity for characterizing a lesion as benign ranged from 47% at a threshold of 2 H to 88% at a threshold of 20 H. Similarly, specificity varied from 100% at a threshold of 2 H to 84% at a threshold of 20 H.
The attempt to be absolutely certain that an adrenal lesion is benign may lead to an unacceptably low sensitivity for lesion characterization. The threshold chosen will depend on the patient population and the cost-benefit approach to patient care.
The efficacy and tolerability of an antiretroviral regimen are important considerations for selection of HIV-1 infection maintenance therapy. Abacavir/lamivudine plus rilpivirine (ABC/3TC + RPV) has ...been shown in international studies to be effective and well-tolerated in virologically suppressed individuals. This study evaluated the effectiveness and safety of switching to ABC/3TC + RPV as maintenance therapy in virologically suppressed HIV-1 infected individuals in Singapore.
In this retrospective, single-centre study, we included individuals who were prescribed ABC/3TC + RPV, had HIV-1 viral load (VL) < 50 copies/ml immediately pre-switch, and had no documented history of resistance mutations or virologic failure to any of the components. The follow-up period was 48 ± 12 weeks. The primary outcome was the proportion of individuals who maintained virologic suppression of HIV-1 VL < 50 copies/ml at the end of follow-up period based on on-treatment analysis. The secondary outcomes were the resistance profiles associated with virologic failure, changes in immunologic and metabolic parameters, and the safety profile of ABC/3TC + RPV.
A total of 222 individuals were included in the study. The primary outcome was achieved in 197 individuals 88.8%, 95% confidence interval: 83.7-92.4%. There were 21 individuals (9.5%) who discontinued treatment for non-virologic reasons. The remaining 4 individuals experienced virologic failure, of whom, 3 of these individuals had developed emergent antiretroviral resistance and had HIV-1 VL > 500 copies/ml at the end of the 48 ± 12 weeks follow-up period. The remaining individual experienced sustained low level viremia and subsequently achieved viral suppression without undergoing resistance testing. A total of 49 adverse events were observed in 31 out of 222 individuals (14.0%), which led to 13 individuals discontinuing therapy. Neuropsychiatric adverse events were most commonly observed (53.1%). A statistically significant increase in CD4 was observed (p < 0.01), with a median absolute change of 31 cells/uL (interquartile range: - 31.50 to 140.75). No significant changes in lipid profiles were detected.
ABC/3TC + RPV is a safe and effective switch option for maintenance therapy in virologically suppressed HIV-1 individuals with in Singapore.
OBJECTIVES: To evaluate immediate and long-term outcomes of bronchial artery embolisation (BAE) for the treatment of haemoptysis in patients with pulmonary tuberculosis (TB), and to clarify factors ...that influence recurrence.DESIGN: Of 398 patients with haemoptysis who underwent
BAE between January 2004 and June 2009, 169 were retrospectively reviewed. All of the patients had either a history of pulmonary TB or a current diagnosis of TB. Follow-up ranged from 1 day to 66 months.RESULTS: Haemoptysis was stopped or markedly decreased, with subsequent clinical improvement,
in 163 patients (96.4%); in 50 patients symptoms recurred during the follow-up period. Disease activity, aortography and mycetoma showed a statistically significant correlation with recurrence rate. Cumulative non-recurrence rates were 76.1% for 12 months and 51.4% for 40months. The median
non-recurrence time was 41.2 months. Disease activity and mycetoma showed a statistically significant correlation with early recurrence. Only one major complication was observed.CONCLUSIONS: BAE is a safe and effective treatment option for the control of haemoptysis in TB patients. Disease
activity and mycetoma both correlate with higher recurrence rate and early time of recurrence.
Abstract Objective Chronic kidney disease (CKD) is characterized by metabolic disturbances in calcium and phosphorus homeostasis as kidney function declines. Alterations in blood perfusion in bone ...resulting from arteriosclerosis of bone vessels may relate to the progression of CKD. Herein, change in dynamic contrast enhanced (DCE) MRI parameters ( A:amplitude , k el :elimination constant , and k ep :permeability rate constant ) and MRI T2 * relaxation time of the knee cartilage were measured in a rodent nephrectomy model in order to i) examine the relationship of peripheral blood perfusion to CKD and ii) demonstrate the feasibility of using DCE MRI parameters and MRI T2 * as imaging biomarkers to monitor disease progression. Design Two groups of male Sprague Dawley rats received either i) no intervention or ii) 5/6 nephrectomy. Results We found that the CKD group (compared with the control group) had lower A and k el values and similar k ep value in the lateral and medial articular cartilages beginning at 12 weeks (p <0.05); statistically significantly higher T2 * values in the lateral and medial articular cartilages beginning at 18 weeks (p<0.05); statistically significantly decreased inner luminal diameter of the popliteal artery, and altered structure of the lateral and medial articular cartilages (p <0.05). Conclusion Perfusion deficiency and CKD may be related. DCE parameters and MRI T2 * could serve as imaging biomarkers of cartilage degeneration in CKD progression.
Melaleucaeae is the second largest angiosperm tribe in Australia containing more than 330 species. Most
Melaleuca
species are endemic to Australia and are found in a wide variety of habitats. The
...Melaleuca leucadendra
complex, including
M. leucadendra
,
M. quinquenervia
and
M. viridiflora
, are dominant components of the tropical and sub-tropical biota of Australia. All three species are known to be susceptible to
Austropuccinia psidii
(myrtle rust), which was first detected in Australia in 2010 and is now widespread in the eastern states and the Northern Territory. In this study we examined variability in susceptibility to
A. psidii
within populations of
M. quinquenervia, M. leucadendra
and
M. viridiflora
using in-vitro assessments of seedlings from provenances across the native range of the three species. We identified wide variation in susceptibility to
A. psidii
between
M. quinquenervia
,
M. leucadendra
and
M. viridiflora
, among provenances within these species as well as within provenances. Further studies on larger populations of these
Melaleuca
species addressing the long-term impacts of repeated infection in native ecosystems are needed to not only help predict but also limit impact. Regaining lost genetic diversity within some of these species populations may require human intervention.
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