The annual modulation signal observed by the DAMA experiment is a long-standing question in the community of dark matter direct detection. This necessitates an independent verification of its ...existence using the same detection technique. The COSINE-100 experiment has been operating with 106 kg of low-background NaI(Tl) detectors providing interesting checks on the DAMA signal. However, due to higher backgrounds in the NaI(Tl) crystals used in COSINE-100 relative to those used for DAMA, it was difficult to reach final conclusions. Since the start of COSINE-100 data taking in 2016, we also have initiated a program to develop ultra-pure NaI(Tl) crystals for COSINE-200, the next phase of the experiment. The program includes efforts of raw powder purification, ultra-pure NaI(Tl) crystal growth, and detector assembly techniques. After extensive research and development of NaI(Tl) crystal growth, we have successfully grown a few small-size (0.61–0.78 kg) thallium-doped crystals with high radio-purity. A high light yield has been achieved by improvements of our detector assembly technique. Here we report the ultra-pure NaI(Tl) detector developments at the Institute for Basic Science, Korea. The technique developed here will be applied to the production of NaI(Tl) detectors for the COSINE-200 experiment.
We report the experimental realization of an optical trap that localizes single Cs atoms ≃215 nm from the surface of a dielectric nanofiber. By operating at magic wavelengths for pairs of ...counterpropagating red- and blue-detuned trapping beams, differential scalar light shifts are eliminated, and vector shifts are suppressed by ≈250. We thereby measure an absorption linewidth Γ/2π=5.7±0.1 MHz for the Cs 6S(1/2), F=4→6P(3/2), F'=5 transition, where Γ0/2π=5.2 MHz in free space. An optical depth d≃66 is observed, corresponding to an optical depth per atom d1≃0.08. These advances provide an important capability for the implementation of functional quantum optical networks and precision atomic spectroscopy near dielectric surfaces.
Although gastric cancer screening is common among countries with a high prevalence of gastric cancer, there is little data to support the effectiveness of this screening. This study was designed to ...determine the differences in stage at diagnosis of gastric cancer according to the screening history and screening method (upper gastrointestinal series (UGIS) vs endoscopy).
The study population was derived from the National Cancer Screening Programme (NCSP), a nationwide organised screening programme in Korea. The study cohort consisted of 19 168 gastric cancer patients who had been diagnosed in 2007 and who were invited to undergo gastric cancer screening via the NCSP between 2002 and 2007.
Compared with never-screened patients, the odds ratios for being diagnosed with localised gastric cancer in endoscopy-screened patients and UGIS-screened patients were 2.10 (95% CI=1.90-2.33) and 1.24 (95% CI=1.13-1.36), respectively.
Screening by endoscopy was more strongly associated with a diagnosis of localised stage gastric cancer compared with screening by UGIS.
► Effect of temperature on permeability of naturally fractured coal. ► Triaxial test for experiments and COMET 3 software for numerical simulation. ► CO2 permeability increases with increasing ...temperature at high injecting pressures. ► Temperature does not affect much on CO2 permeability at low injecting pressures. ► Rate of permeability increment with temperature reduces after around 90°C.
Very deep coal seams which are unlikely to be mined may be considered for CO2 sequestration. The main objective of this study is to investigate the effect of temperature on the permeability of naturally fractured coal. Permeability tests were conducted on naturally fractured bituminous coal samples using high pressure triaxial equipment for five different injecting pressures (8–13MPa) under two different confinements (20 and 24MPa) and five different temperatures (25–70°C). The experimental data were then used to develop an appropriate numerical model using the COMET 3 simulator to model the temperature effect on permeability at temperatures up to 200°C. According to the measured permeability values and the developed lab-scale model, there is a clear increase in CO2 permeability with increasing temperature for any confining pressure at high injecting pressures (more then 10MPa). However, for low injecting pressures (less than 9MPa) temperature effect is not so much. With increasing injecting pressure, CO2 permeability decreases at low temperatures (less than around 40°C), and increases at high temperatures (more than 50°C). Interestingly, the temperature effect on permeability is significant only up to around 90°C condition within the 25–200°C temperature limit. These observations are related with the sorption behavior of the adsorbing CO2 during the injection. However, there is no noticeable temperature effect on N2 permeability as it does not create any swelling effect in coal matrix.
The integration of nanophotonics and atomic physics has been a long-sought goal that would open new frontiers for optical physics, including novel quantum transport and many-body phenomena with ...photon-mediated atomic interactions. Reaching this goal requires surmounting diverse challenges in nanofabrication and atomic manipulation. Here we report the development of a novel integrated optical circuit with a photonic crystal capable of both localizing and interfacing atoms with guided photons. Optical bands of a photonic crystal waveguide are aligned with selected atomic transitions. From reflection spectra measured with average atom number N=1.1+/-0.4, we infer that atoms are localized within the waveguide by optical dipole forces. The fraction of single-atom radiative decay into the waveguide is Γ1D/Γ'≃(0.32±0.08), where Γ1D is the rate of emission into the guided mode and Γ' is the decay rate into all other channels. Γ1D/Γ' is unprecedented in all current atom-photon interfaces.
These two cohorts were designed to examine the increasing burden of chronic diseases among Korean populations. The studies investigated determinants for stroke, osteoporosis, dementia and cancer ...among middle-aged and elderly Korean populations. The Namwon Study baseline survey was performed between 2004 and 2007 (n = 10 667), and followed up 4 years later (n = 8157, follow-up rate = 76.5%). The baseline survey of the Dong-gu Study was administered over 2007–2010 (n = 9260), and will be followed up between 2014 and 2015. Questionnaires included assessment of cognitive function, psychiatric health and lifestyle factors. Clinical examinations, biochemical tests and genotyping focused on evaluating the determinants of target diseases and their intermediate phenotypes. Potential collaborators will be invited to contact the chief investigators.
Aims/hypothesis New genetic variants associated with susceptibility to type 2 diabetes mellitus have been discovered in recent genome-wide association (GWA) studies. The aim of the present study was ...to examine the association between these diabetogenic variants and gestational diabetes mellitus (GDM). Methods The study included 869 Korean women with GDM and 345 female and 287 male Korean non-diabetic controls. We genotyped the single nucleotide polymorphisms (SNPs) rs7756992 and rs7754840 in CDKAL1; rs564398, rs1333040, rs10757278 and rs10811661 in the CDKN2A-CDKN2B region; rs8050136 in FTO; rs1111875, rs5015480 and rs7923837 in HHEX; rs4402960 in IGF2BP2; and rs13266634 in SLC30A8. In addition, rs7903146 and rs12255372 in TCF7L2; rs5215 and rs5219 in KCNJ11; and rs3856806 and rs1801282 in PPARG were genotyped. The genotype frequencies in the GDM patients were compared with those in the non-diabetic controls. Results Compared with controls (men and women combined), GDM was associated with rs7756992 and rs7754840 (OR 1.55, 95% CI 1.34-1.79, p = 4.17 x 10⁻⁹) in CDKAL1; rs10811661 (OR 1.49, 95% CI 1.29-1.72, p = 1.05 x 10⁻⁷) in the CDKN2A-CDKN2B region; rs1111875 (OR 1.27, 95% CI 1.09-1.49, p = 0.003), rs5015480, and rs7923837 in HHEX; rs4402960 (OR 1.18, 95% CI 1.01-1.38, p = 0.03) in IGF2BP2; rs13266634 (OR 1.24, 95% CI 1.07-1.43, p = 0.005) in SLC30A8; and rs7903146 (OR 1.58, 95% CI 1.03-2.43, p = 0.038) in TCF7L2. The risk alleles of the SNPs rs7756992 and rs7754840 in CDKAL1; rs10811661 in the CDKN2A-CDKN2B region; and rs1111875, rs5015480 and rs7923837 in HHEX were associated with significant decreases in the insulin AUC during a 100 g OGTT performed at the time of diagnosis of GDM. Conclusions/interpretation Some of the type 2 diabetes-associated genetic variants that were discovered in the recent GWA studies are also associated with GDM in Koreans.
Background
In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been ...suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection.
Methods
Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted.
Results
Data from 937 patients were available for evaluation. The overall 5‐year disease‐free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5‐year disease‐free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5‐year disease‐free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five‐year disease‐free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic.
Conclusion
Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.
Antecedentes
En el cáncer de vesícula biliar, la ubicación del tumor subdivide el estadio T2 en tumores con invasión del lado peritoneal y del lado del hígado (T2a y T2b). Para los tumores que invaden el lado peritoneal (T2a) se sugiere que se puede obviar la resección hepática sin que ello comprometa el pronóstico. Sin embargo, este argumento no ha sido validado. El estudio tuvo como objetivo investigar el valor pronóstico de la localización del tumor en el cáncer de vesícula biliar T2 y establecer la extensión adecuada de la resección quirúrgica.
Métodos
Se recogieron los datos clínicos de pacientes que se sometieron a cirugía por cáncer de vesícula biliar en 14 hospitales de Corea, Japón, Chile y Estados Unidos. Se realizaron análisis de la supervivencia y de los factores de riesgo.
Resultados
Se dispuso de datos de 937 pacientes para ser evaluados. La tasa de supervivencia global libre de enfermedad a los 5 años fue del 70,6%, y las de T2a y T2b del 74,5% y 65,5% (P = 0,028). Con respecto a la resección hepática, la colecistectomía extendida presentó una tasa mejor de supervivencia libre de enfermedad a los 5 años que la colecistectomía simple (73,0% versus 61,5%, P = 0,012). La tasa de supervivencia libre de enfermedad a los 5 años fue marginalmente mejor para la colecistectomía extendida que para la colecistectomía simple tanto en T2a (76,5% versus 66,1%, P = 0,094) como en T2b (68,2% versus 56,2%, P = 0,084). Las tasas de supervivencia libre de enfermedad a los 5 años no fueron diferentes entre la resección hepática en cuña y la segmentectomía S4b+S5 (74,1% versus 71,5%, P = 0,720). En el análisis multivariable, los factores de riesgo independientes para la recidiva fueron la presencia de síntomas (cociente de riesgos instantáneos, hazard ratio, HR 1,52, P = 0,002), la resección R1 (HR 1,96, P = 0,004) y el estadio N1/N2 (N1 HR 3,40, P < 0,001; N2 HR 9,56, P < 0,001). El 70,8% de las recidivas eran metastásicas.
Conclusión
La localización del tumor no fue un factor pronóstico independiente en el cáncer de vesícula biliar T2. La colecistectomía extendida fue marginalmente superior que la colecistectomía simple. La cirugía radical debe incluir una resección hepática y una linfadenectomía adecuada.
This multinational multicentre cohort study was undertaken to investigate the prognostic value of tumour location in T2 gallbladder cancer and to clarify the adequate extent of surgical resection. Although tumour location influenced prognosis, it was not an independent prognostic factor in T2 gallbladder cancer. T2 gallbladder cancer requires extended cholecystectomy including hepatic resection and lymph node dissection, regardless of the location.
challenges current TNM system