Xenon dual-phase time projection chambers designed to search for weakly interacting massive particles have so far shown a relative energy resolution which degrades with energy above
∼
200 keV due to ...the saturation effects. This has limited their sensitivity in the search for rare events like the neutrinoless double-beta decay of
136
Xe
at its
Q
value,
Q
β
β
≃
2.46
MeV
. For the XENON1T dual-phase time projection chamber, we demonstrate that the relative energy resolution at
1
σ
/
μ
is as low as (
0.80
±
0.02
) % in its one-ton fiducial mass, and for single-site interactions at
Q
β
β
. We also present a new signal correction method to rectify the saturation effects of the signal readout system, resulting in more accurate position reconstruction and indirectly improving the energy resolution. The very good result achieved in XENON1T opens up new windows for the xenon dual-phase dark matter detectors to simultaneously search for other rare events.
The aim of this research is to support the assessment of countries’ risks of water conflicts in the immediate future, considering their vulnerability to changes in water availability. The risk of ...international water conflicts in the 5 years ahead of the year of analysis was estimated based on current water availability and its unequal distribution. Countries were classified by their vulnerability to reductions in water availability. In these vulnerability groups, the links of water availability (TRIP discharges per capita) and its unequal distribution with the risk of water conflicts were explored. The Gini Coefficient was employed to measure the inequalities. Inequalities showed statistically significant positive Logit links with the risk of water conflicts. The greatest risk for volatile conflicts exists for the Asian, South American and African countries, having the lowest water availability and the lowest economic capacity. Increasing inequalities increases the likelihood of water conflicts, suggesting enhancing access to water, to lower the likelihood of water conflicts. South American and Congo River basin countries are only at risk of low-level water conflicts, but have higher risks of conflict escalation, when inequality increases. The risk of North American and Asian water conflicts were modeled well, except in western Asia. The water conflict estimation provided only 11.9 % under-estimations and an accuracy of 54.1 %, globally. Inequalities in water can indicate the risk of water conflicts in the above regions. However, the risk of water conflicts between countries with higher economic capacity in the European continent showed no link with inequality. This study will facilitate the estimation of the risk of water conflicts resulting from climate change.
The selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are ...reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and
222
Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described. Screening results, used as inputs for a XENONnT Monte Carlo simulation, predict a reduction of materials background (
∼
17%) with respect to its predecessor XENON1T. Through radon emanation measurements, the expected
222
Rn activity concentration in XENONnT is determined to be 4.2 (
-
0.7
+
0.5
)
μ
Bq/kg, a factor three lower with respect to XENON1T. This radon concentration will be further suppressed by means of the novel radon distillation system.
Abstract
Background and purpose
Fluorine-18-flurodeoxyglucose positron emission tomography (18FDG-PET) is a useful examination assessing active inflammatory myocardium noninvasively in patients with ...cardiac sarcoidosis (CS). Though immunosuppression like prednisolone (PSL) and Methotrexate (MTX) as alternative therapy is used to suppress the inflammation, little is known about the rate of response and efficacy of MTX for intolerance to PSL therapy.
Methods
From Aug 2016, we prospectively enrolled CS with positively accumulated of FDG in the heart. The initial dose of PSL was 30mg/day, wherefrom the dose was tapered down 5mg/month until 6 months. After 6 months, follow-up 18FDG-PET was performed. Using 18FDG-PET images, we calculated total lesion glycolysis (TLG; SUVmeam x metabolic volume) and calculated the reduction rate of TLG. In order to estimate the response rate to PSL therapy, responder group (R-group) was defined as TLG reduction rate ≥70% and poor-responder group (PR-group) was defined as TLG reduction rate <70% after PSL therapy. After prescribed PSL, subjects with PR-group randomized to PSL (maximum dose 30mg daily and tapered down 5mg/month until 6 months) or to MTX (6mg weekly).
Results
In 64 CS patients, 55 patients had serial 18FDG-PET before and 6 months after PSL therapy. 18FDG-PET images were acquired following 7 day's carbohydrate limitation and after at least 18-h fasting (mean free fatty acid level right before 18FDG-PET acquisition was 1.05 mEq/L). The mean age was 63.4 years old and 42 (76.4%) patients were female. Because of 6 months PSL therapy, even though there were no significant difference in BNP (from 59.9 (26.2–137.6) to 60.4 (18.5–122.0) (P=0.593), LV-Dd (from 50.9 (44.5–59.5) to 49.7 (45.5–61.3) (P=0.666) and LV-EF (from 49.5 (34.4–62.5) to 49.9 (38.0–62.0) (P=0.792) at pre and post therapy, respectively, TLG were detected significant reduction from 216.4 (74.2–411.6) to 0.8 (0.0–8.2), (p<0.001). In response to PSL therapy, 47 (85.5%) CS patients were classified to R-group and 8 (14.5%) were classified to PR-group. Furthermore, when performed block randomization and divide 8 PR-group patients into MTX (n=3) and re-increased PSL (n=5) for more 6 months, MTX group is prone to high rate of TLG reduction than re-increased PSL-group (89.4% vs 59.9%) and one patient belonged to re-increased PSL group showed that the further elevation of TLG level at additional 6-months PSL therapy (349⇒483) (Figure).
Conclusions
1) By immunosuppression therapy using PSL for CS, about 86% patients showed significant reduction of myocardial FDG accumulation. 2) When detected intolerance for PSL therapy, MTX might be effective for reduction of inflammation of sarcoidosis in the heart, which might be effective as an alternate therapy in CS.
The TLG level after randomization
Funding Acknowledgement
Type of funding source: Public Institution(s). Main funding source(s): Grant-in-aid for scientific research
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