Diurnal cycles of precipitation and lightning are investigated by analyzing rain rates of the TRMM3G68 dataset, consisting of Precipitation Radar and Microwave Imager data only; rain rates of Global ...Satellite Mapping of Precipitation (GSMaP), for which infrared (IR) data are also used; lightning flash rates observed by TRMM Lightning Imaging Sensor (LIS); and lightning stroke rates of World Wide Lightning Location Network (WWLLN) over the tropics. Diurnal amplitudes relative to averages are generally larger for lightning than for precipitation. Over ocean, relative amplitudes are stronger in the stratocumulus deck region in the southeast Pacific than those over typical ocean regions. The phase of GSMaP is substantially delayed to TRMM3G68 due to the phase-delay problem of IR-based estimation. The diurnal peaks tend to occur between 1400 and 1800 LST over the continent after spatial averaging with a phase leading order of TRMM3G68, LIS, and WWLLN, and between 0000 and 0700 LST over oceanic regions where diurnal cycles are prominent in all datasets. Off-equatorward phase propagations are found in the precipitation in the Pacific and Indian Oceans. Over selected coastal regions, all data exhibit consistent oceanward phase propagation with the longest, medium, and shortest phase propagation distances for TRMM3G68 precipitation, WWLLN lightning, and LIS lightning, respectively, with a phase leading order of LIS, WWLLN, and TRMM3G68. The summertime diurnal cycle over the Gulf Stream also exhibits oceanward phase propagation, but with strong amplitude enhancement over the Gulf Stream. Diurnal cycle amplitude is also enhanced over the Kuroshio in the East China Sea in the baiu–mei-yu rainy season.
An Electron Beam Ion Source (EBIS) will be utilized for charge breeder in the RAON heavy ion accelerator facility. The vacuum system for the RAON EBIS charge breeder is crucial part for the ...achievable charge state, breeding efficiency, and purity of the charge-bred beam. A strict vacuum level of about 10−11 mbar is required in the ion trap. The pumping system of the RAON EBIS charge breeder consists of turbo pumps (TMPs), cryo-pumps, and non-evaporable getter (NEG) ZAO modules. The material for the ion trap structures and vacuum chamber was chosen and handled carefully to satisfy the vacuum requirements in the manufacturing step with vacuum firing at 1050 °C for 2 h. A vacuum test of the ion trap section has been performed with baking, and final vacuum level reached 2.3 × 10−11 mbar. In this paper, the vacuum system of the RAON EBIS and test procedures and results are presented and discussed.
•Electron Beam Ion Source charge breeder for the RAON heavy ion accelerator.•UHV system for the EBIS charge breeder.•Enhancement vacuum environment using high compression ratio TMP and NEG ZAO.
A time-of-flight (TOF) system adopting single reflection has been constructed to identify the charge states of ions charge-bed by using the electron beam ion source (EBIS). The reflection allows for ...time focusing of the system in a compact manner. The EBIS under construction will enhance the charge states of rare isotopes produced by isotope separation on line (ISOL) so as to utilize the superconducting post linear accelerator efficiently. The TOF system consists of an ion-gate, reflection electrodes and multi-channel plates (MCP) detector. The maximum voltage on ions is 20 kV, and the beam optics design was performed using SIMION. In the front end of the TOF an ion gate is located to produce a single 5- to 10-ns pulse operating at a maximum voltage of
±
1 kV. The circuit of the fast switching system, which converts
-
1 kV to 1 kV in a few ns, was simulated for an equivalent circuit of the gate by using LTspice. The TOF system is being fabricated and will be connected to a Cs ion source for initial beam tests with Cs
1+
mixed with background ions.
In Korea, a heavy ion accelerator facility called RAON is being designed to produce various rare isotopes for the Rare Isotope Science Project (RISP) (Jeong, 2016) 1, (Moon, 2014) 2. This facility is ...designed to use both In-flight Fragment (IF) and Isotope Separation On-Line (ISOL) techniques in order to produce a wide variety of RI beams for nuclear physics experiments. An Electron Beam Ion Source (EBIS) will be used for charge breeding of Rare Isotope (RI) beams in the ISOL system. The charge-to-mass ratio (q/A) of the RI beams after charge breeding is ≥1/4. The highly charged RI beams will be accelerated by a linac post-accelerator and delivered to a low energy (∼18MeV/u) experimental hall or the IF system. The RAON EBIS will use a 3A electron gun and a 6T superconducting solenoid for high capacity, high efficiency, and short breeding time. In front of the charge breeder, an RFQ cooler-buncher will be used to deliver a bunched beam with small emittance to the EBIS charge breeder. The main design of the RAON EBIS has been carried out on the basis of several beam analyses and technical reviews. In this paper, current progress of the development of the RAON EBIS charge breeder will be presented.
Rare-isotope beams will be produced by using the isotope separation on-line (ISOL) system at the Rare Isotope Science Project (RISP). A proton cyclotron is the driver accelerator for ISOL targets, ...and uranium carbide (UCx) will be a major target material. An isotope beam of interest extracted from the target will be ionized and selected by using a mass separator. The beam emittance will then be reduced by using a radio-frequency quadrupole (RFQ) cooler before the beam is injected into the electron-beam ion-source (EBIS) charge breeder (CB). The maximum electron beam current of the EBIS is 3 A from a cathode made of IrCe in an applied magnetic field of 0.2 T. The size of the electron beam is compressed by magnetic fields of up to 6 T caused in the charge-breeding region by a superconducting solenoid. The design of EBIS-CB was performed by using mechanics as well as beam optics. A test stand for the electron gun and its collector, which can take an electron-beam power of 20 kW, are under construction. The gun assembly was first tested by using a high-voltage pulse so as to measure its perveance. The design of the EBIS, along with its test stand, is described.
It is well known that cancer patients' perception of social support is associated with their depressive symptoms and health-related quality of life. However, there have been little studies that ...compared the variates of cancer patients with the general population. We sought to compare differences in the level of perceived social support and the impact of perceived social support on depressive symptoms and health-related quality of life between cancer survivors and the general population.
Data were collected from 1818 cancer patients treated at the National Cancer Center and regional cancer centers in South Korea. The control group of the general population was composed of 2000 individuals without cancer from community.
Cancer patients reported significantly higher level of perceived social support than the general population, while they reported lower health-related quality of life and were more susceptible to depression. The positive associations of higher perceived social support with lower depressive symptoms, as well as with higher health-related quality of life, were stronger among cancer patients than among the general population.
The interaction effect suggests that the impact of social support would be stronger among cancer patients than the general public. Thus, it would be beneficial to pay attention to providing social support to cancer patients, particularly to those who are more vulnerable. Furthermore, investigation of the most effective and efficient methods to deliver social support interventions would be worthwhile.
A complete enumeration study was conducted to evaluate trends in national practice patterns and direct medical costs for prostate cancer (PCa) in Korea over a 10-year retrospective period using data ...from the Korean National Health Insurance Service.
Reimbursement records for 874,924 patients diagnosed between 2002 and 2014 with primary PCa according to the International Classification of Disease (ICD) 10th revision code C61 were accessed. To assess direct medical costs for patients newly diagnosed after 2005, data from 68,596 patients managed between January 2005 and 31 December 2014 were evaluated.
From 2005 to 2014, the total number of PCa patients showed a 2.6-fold increase. Surgery and androgen deprivation therapy were the most common first-line treatment, alone or within the context of combined therapy. Surgery as a monotherapy was performed in 23.5% of patients in 2005, and in 39.4% of patients in 2014. From 2008, the rate of robot-assisted RP rose sharply, showing a similar rate to open RP in 2014. Average total treatment costs in the 12 months post-diagnosis were around 10 million Korean won. Average annual treatment costs thereafter were around 5 million Korean won. Out-of-pocket expenditure was highest in the first year post-diagnosis, and ranged from 12 to 17% thereafter.
Between 2005 and 2014, a substantial change was observed in the national practice pattern for PCa in Korea. The present data provide a reliable overview of treatment patterns and medical costs for PCa in Korea.
The aim of this study was to investigate whether aspirin use can reduce the incidence of gastric cancer in patients with hypertension or type 2 diabetes.
A total of 200,000 patients with hypertension ...or type 2 diabetes were randomly selected from the Korean National Health Insurance claim database. Of these, 3,907 patients who used 100 mg of aspirin regularly (regular aspirin users) and 7,808 patients who did not use aspirin regularly (aspirin non-users) were selected at a frequency of 1:2, matched by age, sex, comorbid illnesses (type 2 diabetes and hypertension), and observation periods. The incidence of gastric cancer in this cohort was then assessed during the observation period of 2004 to 2010.
In the matched cohort, the incidence rates of gastric cancer were 0.8% (31/3,907) for regular aspirin users and 1.1% (86/7,808) for aspirin non-users, but the cumulative incidence rates were not significantly different between groups (p=0.116, log-rank test). However, in multivariate analysis, regular aspirin users had a reduced risk of gastric cancer (adjusted hazard ratio aHR, 0.71; 95% confidential interval CI, 0.47 to 1.08; p=0.107). Duration of aspirin use showed significant association with reduction of gastric cancer risk (aHR for each year of aspirin use, 0.85; 95% CI, 0.73 to 0.99; p=0.044), particularly in patients who used aspirin for more than 3 years (aHR, 0.40; 95% CI, 0.16 to 0.98; p=0.045).
Long-term low-dose aspirin use was associated with reduced gastric cancer risk in patients with hypertension or type 2 diabetes.
Adolescents who reenter school after treatment for cancer may face certain challenges, such as social exclusion by their peers and difficulties in cognitive functioning, due to the cancer treatment ...and its psychosocial sequelae. Such challenges may have an impact on their mental health. This cross-sectional study examined the impact of peer exclusion-victimization and cognitive functioning on depression among adolescent survivors of childhood cancer. A total of 175 adolescent survivors of childhood cancer between the ages of 13 and 19 years completed a self-reported questionnaire. Their mean age was 15.33 years (SD = 1.65), the mean time since diagnosis was 7.97 years (SD = 3.91), and 49.7% experienced at least 1 kind of peer exclusion in school. Multiple regression analysis was conducted to examine the effects of survivors' experiences related to peer exclusion-victimization and cognitive functioning on depression, controlling for demographic (age and gender) and cancer-related (cancer type, time since diagnosis, recurrence) characteristics. The model with peer exclusion-victimization and cognitive functioning as predictors accounted for 27.9% of the variance in depression. More experiences in peer exclusion-victimization (β = .200, p = .024) and lower cognitive functioning (β = -.465, p < .001) were associated with greater levels of depression. Understanding the impact of survivors' experiences of peer exclusion-victimization and cognitive functioning on their mental health will help professionals to provide appropriate counseling services to moderate peer exclusion-victimization as well as resources for academic performance for those cancer survivors at risk for depression.
Public Policy Relevance Statement
Reentering school after cancer treatment can be a major challenge for adolescent cancer survivors in South Korea. This study suggests that school policies should provide adolescent cancer survivors with a physically and emotionally safe learning environment at the micro, meso, and macro levels.
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