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We consider a panel cointegration model with latent group structures that allows for heterogeneous long-run relationships across groups. We extend Su, Shi, and Phillips (2016, Econometrica 84(6), 2215–2264) classifier-Lasso (C-Lasso) method to the nonstationary panels and allow for the presence of endogeneity in both the stationary and nonstationary regressors in the model. In addition, we allow the dimension of the stationary regressors to diverge with the sample size. We show that we can identify the individuals’ group membership and estimate the group-specific long-run cointegrated relationships simultaneously. We demonstrate the desirable property of uniform classification consistency and the oracle properties of both the C-Lasso estimators and their post-Lasso versions. The special case of dynamic penalized least squares is also studied. Simulations show superb finite sample performance in both classification and estimation. In an empirical application, we study the potential heterogeneous behavior in testing the validity of long-run purchasing power parity (PPP) hypothesis in the post–Bretton Woods period from 1975–2014 covering 99 countries. We identify two groups in the period 1975–1998 and three groups in the period 1999–2014. The results confirm that at least some countries favor the long-run PPP hypothesis in the post–Bretton Woods period.
Annexin A2 (ANXA2) is reported to be associated with cancer development. To investigate the roles ANXA2 plays during the development of cancer, the RNAi method was used to inhibit the ANXA2 expression in caco2 (human colorectal cancer cell line) and SMMC7721 (human hepatocarcinoma cell line) cells. The results showed that when the expression of ANXA2 was efficiently inhibited, the growth and motility of both cell lines were significantly decreased, and the development of the motility relevant microstructures, such as pseudopodia, filopodia, and the polymerization of microfilaments and microtubules were obviously inhibited. The cancer cell apoptosis was enhanced without obvious significance. The possible regulating pathway in the process was also predicted and discussed. Our results suggested that ANXA2 plays important roles in maintaining the malignancy of colorectal and hepatic cancer by enhancing the cell proliferation, motility, and development of the motility associated microstructures of cancer cells based on a possible complicated signal pathway.
Tropospheric delay is one of the main error sources in Global Navigation Satellite System (GNSS) Precise Point Positioning (PPP). Zenith Hydrostatic Delay (ZHD) accounts for 90% of the total delay. This research focuses on the improvements of ZHD from tropospheric models and real meteorological data on the PPP solution. Multi-GNSS PPP experiments are conducted using the datasets collected at Multi-GNSS Experiments (MGEX) network stations. The results show that the positioning accuracy of different GNSS PPP solutions using the meteorological data for ZHD correction can achieve an accuracy level of several millimetres. The average convergence time of a PPP solution for the BeiDou System (BDS), the Global Positioning System (GPS), Global Navigation Satellite System of Russia (GLONASS), BDS+GPS, and BDS+GPS+GLONASS+Galileo are 55·89 min, 25·88 min, 33·30 min, 20·50 min and 15·71 min, respectively. The results also show that atmospheric parameters provided by real meteorological data have little effect on the horizontal components of positioning compared to the meteorological model, while in the vertical component, the positioning accuracy is improved by 90·6%, 33·0%, 22·2% and 19·8% compared with the standard atmospheric model, University of New Brunswick (UNB3m) model, Global Pressure and Temperature (GPT) model, and Global Pressure and Temperature-2 (GPT2) model and the convergence times are decreased 51·2%, 32·8%, 32·5%, and 32·3%, respectively.
The Korea National Health Insurance (K-NHI) has covered medical devices with low cost-effectiveness evidence by what is known as the Selective Benefit (SB) since December of 2013 as a type of conditional coverage. Most medical devices in the SB category are new technology and have higher levels of clinical effectiveness and/or functions than those in the benefit category, but they are characterized as being expensive. We compare the K-NHI medical device coverage system to those in Japan and Taiwan so as to be more informed about how to cover and set prices for new medical devices.
We searched for materials related to medical device coverage or the reimbursement systems of three countries (Korea, Japan, and Taiwan). National health insurance laws, policy reports, and the websites of the Ministries of Health of the respective countries, for instance, were also reviewed.
The NHI systems of Korea, Japan, and Taiwan have several similarities with regard to their medical device benefit lists. They reimburse listed medical devices separately although they cover them basically by including procedures or a diagnosis-related group (DRG) fee. The K-NHI reimburses for medical devices with low cost-effectiveness using the actual market medical price, similar to other medical devices in the benefit category. However, there are no detailed rules regarding how to set prices for these devices. Every listed medical device is covered at the notified price in Japan, but the prices of new medical devices with improved functions can add 1 -100 percent of the price to the notified price. The prices of devices related to new medical procedures are determined by cost-accounting methods. The NHI service in Taiwan compensates for medical devices which are alternates but clinically improved types through a balance billing method.
The NHI systems in Japan and Taiwan set prices with regard to reimbursements for new medical devices separately, specifically for devices which are advanced clinically or functionally but expensive. The K-NHI must consider establishing a pricing or reimbursement system for new medical devices through the discussion with stakeholders for reasonable reimbursements and decreasing the financial burden on the K-NHI.
In indirect drive, reducing peak intensity of a single beam and controlling overlap of multi-beams are two opposite requirements for laser focal spot design. In this paper, an improved laser spot design technique for indirect drive built upon the geometric structures of laser propagation into hohlraum has been introduced. The proposed technique is able to generate appropriate continuous phase plate (CPP) producing a special shaped spot that can balance the opposite requirements. The corresponding CPP does not bring difficulties to the design and fabrication. Phase aberrations are more sensitive to the special shaped spot; however, it can be tolerable for the current beam control level.
In this work, the high-performance silicon carbide particle SiCp[carbon nanotube (CNT)] hybrid reinforcement is currently explored to develop the advanced metal matrix composites. 17 wt% SiCp(CNT)/Al composites were fabricated by a powder metallurgy technique, in which SiCp(CNT) hybrid reinforcement with various CNT contents (e.g., 3, 6 and 9 wt%) were applied. Effects of CNT content on the morphology of SiCp(CNT) hybrid reinforcement, the microstructural characteristics, and the tensile mechanical behavior of SiCp(CNT)/Al composites were studied as well. Especially, the SiCp(CNT)/Al composites with 6 wt% CNT in SiCp(CNT) hybrid reinforcement exhibited the most significant enhancing effects in the elastic modulus and tensile strength. Meanwhile, the SiCp(CNT)/Al composites produced a synergistic strengthening effect of SiCp and CNT compared to SiCp/Al composites, while the SiCp(CNT)/Al composites with high CNT content in SiCp(CNT) hybrid reinforcement provided weak improvement in the tensile strength and ductility due to the forming agglomeration of CNT in the matrix.
Previous studies have thoroughly investigated the prevalence and risk factors for completed suicide. In marked contrast is the lack of a better understanding of attempted suicide in the elderly. The aim of this study was to estimate the prevalence of attempted suicide in the elderly and examine the associated factors.
Using a multi-stage cluster sampling approach, a cross-sectional survey of 8,399 elderly house-dwelling residents was conducted in Shanghai, China.
The two-week prevalence of attempted suicide in the elderly was 0.75%. In the bivariate analysis, having no caregivers, depressive, anxiety, sad, fear, obsessive-compulsive and anger symptom, and lower scores on the Barthel Index of Activities of Daily Living and the Lawton Instrumental Activities of Daily Living Scale were significantly associated with an increased risk of attempted suicide in the elderly. In the multivariate analysis, sad and fear symptoms were significantly and independently associated with a higher risk of attempted suicide in the elderly.
The two-week prevalence of attempted suicide in the elderly is relatively high when compared with the annualized or lifetime prevalence reported in China and foreign settings. Elderly individuals with certain mental symptoms should be targeted for suicide prevention and provided with timely mental health support.
A life-threatening cardiopulmonary resuscitation (CPR)-related injury can cause recurrent arrest after return of circulation. Such injuries are difficult to identify during resuscitation, and their contribution to failed resuscitation can be missed given the limitations of conventional CPR. Extracorporeal cardiopulmonary resuscitation (ECPR), increasingly being considered for selected patients with potentially reversible etiology of arrest, may identify previously occult CPR-related injuries by restoring arterial pressure and flow. Herein, we describe two cases of severe CPR-related injuries contributing to recurrent arrest. Each case had ECPR implemented within 60 minutes of the start of CPR. After the presumed cardiac etiology had been addressed with percutaneous coronary intervention, life-threatening cardiovascular injuries with recurrent arrest were noted, and resuscitative thoracotomy was performed under ECPR. One patient survived to hospital discharge.
ECPR may provide an opportunity to identify and correct severe resuscitation-related injuries causing recurrent arrest. Chest compression depth >6 cm, especially in older women, may contribute to these injuries.
The HoDoo English game was developed to take advantage of the benefits attributed to on-line games while teaching English to native Korean speakers. We expected to see that the improvements in the subjects’ English language abilities after playing the HoDoo English game would be associated with increased brain functional connectivity in the areas of the brain involved in the language production (Broca’s area) and the understanding (Wernicke’s area) networks. Twelve children, aged nine and ten, were asked to play the on-line English education game for 50 minutes per day, five days per week for twelve weeks. At baseline, and again at the end of twelve weeks of game play, each child’s English language ability was assessed and a functional magnetic resonance imaging (fMRI) scan was conducted. The on-line English education game play effectively improved English language skills, especially in terms of non-verbal pragmatic skills. Following twelve weeks of on-line English education game play, the children showed positive connectivity between Broca’s area and the left frontal cortex as well as between Wernicke’s area and the left parahippocampal gyrus and the right medial frontal gyrus. Changes in pragmatic scores were positively correlated with average peak brain activity in the left parahippocampal gyrus. To the best of our knowledge, this is the first study to report an improvement in English ability and changes in brain activity within language areas after on-line language education game play.
Disaster can strike people in any community at any time anywhere in the world. Disasters occur with high frequency, take on multiple forms, and exert wide influence, typically causing property damage, injuries, and death. As the world’s largest developing country, China incurs great costs when a disaster hits. After the Wenchuan earthquake in 2008, the Chinese government focused its attention on the construction of an emergency response system, the creation of disaster prevention and mitigation systems, and the development of a disaster medicine program. Here, we describe the current status of disaster medicine in China, focusing on the following four aspects: the Emergency Management System, Education & Training, Rescue Practices, and Research. We also discuss the future of disaster medicine in China. (Disaster Med Public Health Preparedness. 2018;12:157–165)
Functionalization is critical for improving mechanical properties of carbon nanotubes (CNTs)/polymer nanocomposites. A fundamental understanding of the role of the CNT/polymer interface and bonding structure is key to improving functionalization procedures for higher mechanical performance. In this study, we investigated the effects of chemical functionalization on the nanocomposite interface at atomic resolution to provide direct and quantifiable information of the interactions and interface formation between CNT surfaces and adjacent resin molecules. We observed and compared electronic structures and their changes at the interfaces of nonfunctionalized and functionalized CNT/polymer nanocomposite samples via scanning transmission electron microscopy and electron energy-loss spectroscopy (EELS) spectrum imaging techniques. The results show that the state of sp2 bonding and its distribution at the CNT/resin interface can be clearly visualized through EELS mapping. We found that the functionalized CNT/polymer samples exhibited a lower fraction of sp2 bonding and a lower π*/σ* ratio compared with the nonfunctionalized cases. A good correlation between near-edge fine structures and low-loss plasmon energies was observed.
Asia minor bluegrass (AmB) is a major weed impacting rapeseed production in Dongting Lake District, China. Growth chamber experiments were conducted to determine the influence of environmental factors on germination and emergence of AmB. The optimum constant temperature for germination was around 20 C. Seeds showed germination percentages above 60% under 22/15 and 24/19 C day/night temperature regimes. Seeds could germinate in the dark, but light exposure significantly enhanced the germination percentage. More than 50% of seeds germinated over a pH range between 4 and 10. Seeds were highly sensitive to osmotic stress, and germination was completely inhibited at an osmotic potential of −0.4 MPa, indicating that it was favored by a moist environment. Increasing salinity reduced germination of AmB seeds from 58% at 0 mM to 13% at 80 mM NaCl. The highest seedling emergence (62%) was observed when seeds were placed on the soil surface, and no seedlings emerged from seeds placed at a depth of 5 cm. This work shows that the climate and soil conditions in Dongting Lake District are suitable for AmB seed germination and that no-till fields, where seeds remain on the soil surface, promote the successful establishment of the weed.
This study evaluated the impacts of earlier traumatic events on the mental health of older adults, in terms of mental disorders and mental well-being, according to sociodemographic variables, trauma-related characteristics, and personality traits in a nationally representative sample of older Koreans.
A total of 1,621 subjects aged 60 to 74 years from a Korean national epidemiological survey of mental disorders responded face-to-face interviews. The Korean Composite International Diagnostic Interview was used to investigate lifetime trauma exposure (LTE) and psychiatric diagnoses. The EuroQol health classification system and life satisfaction scale were used to assess quality of life (QoL), and the Big Five Inventory-10 (BFI-10) to measure personality traits.
Five-hundred and seventy-seven subjects (35.6%) reported a history of LTE (mean age at trauma, 30.8 years old). Current mental disorders were more prevalent in elderly people with LTE, while better current QoL was more frequent in those without LTE. Among older people with LTE, lower extraversion and higher neuroticism increased the risk of current mood or anxiety disorders, whereas higher extraversion increased the probability of experiencing mental well-being after adjusting for sociodemographic and trauma-related variables.
Personality traits, especially extraversion, and neuroticism, may be useful for predicting the mental health outcomes of LTE in older adults. Further longitudinal studies investigating the relationship between traumatic events and mental health outcomes are needed.
The transverse navigation system has been designed and developed to solve the challenges of navigation in polar regions. However, considerable theoretical errors are introduced into the system when the spherical Earth model is adopted. To tackle this problem, a transverse navigation mechanism under the ellipsoidal Earth model has been proposed in this research and the application regions of the proposed algorithm are specified and evaluated through error analysis. The analysis shows the presented transverse navigation system works in both polar and part of the non-polar regions. Field tests were conducted to evaluate the navigation performance in Nanjing, a non-polar region. A novel experimental method, where the field test data in mid-latitude areas was used to simulate the real Inertial Measurement Unit (IMU) data and the reference information in polar regions, was adopted to investigate the performance of the proposed algorithm in polar areas. The results show: that in the mid-latitude areas, the presented transverse navigation system achieves the same accuracy as the traditional inertial navigation system and that in polar regions, the proposed transverse mechanism outperforms the traditional method with a much lower error in longitude and yaw.
In Korea, patients with terminal cancer are often caught out of the loop in end-of-life (EoL) care discussions. Healthcare professionals also have difficulty engaging in such communication in a variety of healthcare contexts. Therefore, the objective of our study was to develop a communication model for EoL care decision making compatible with the clinical environment in Korea.
Using focus-group interview methodology, participants included eight doctors and five nurses who provide EoL care for terminal cancer patients in acute hospital settings or hospice care facilities in various provinces of Korea.
Five themes emerged regarding EoL care discussion, which included: (1) timing, (2) responsible professionals, (3) disclosure of bad news, (4) content areas of EoL care discussion, and (5) implementing strategies for EoL care discussions. These themes were based on development of a communication algorithm for EoL discussion among patients with terminal cancer. A structural communication step for delivery of a terminal prognosis was specified at the phase of disclosure of bad news: beginning with determination of a patient's decision-making capability, followed by a patient's perception of his/her condition, a patient's wish to know, family dynamics, and a patient's and/or family's readiness for EoL discussions.
Significance of Results:
The proposed context-oriented communication algorithm could provide a helpful guideline for EoL communication and, accordingly, facilitate meaningful improvements in EoL care in Korean clinical practice. The feasibility of this algorithm has not yet been determined, and its validation in a larger sample of patients with terminal cancers, using a quantitative research methodology, is a priority of research.
Gradual fault detection is always an important issue in integrated navigation systems, and the gradual fault is the most difficult fault to detect. To detect gradual faults in a timely and precise manner in integrated navigation systems, the statistical concepts of the normalised residual mean and the sum of absolute residuals are introduced according to the characteristics of gradual system failure in this paper. The applicability of the improved residual χ2 detection method is discussed. Then, the gradual fault detection program based on the improved residual χ2 detection method is designed with the criterion of normalised residual mean and the sum of absolute residual. The simulation results and vehicle tests show that: 1) The residual of the failed sub-system can be calculated accurately with the improved residual χ2 detection method, which has strong applicability in gradual fault detection; 2) The gradual fault can be detected in a short time by using the normalised residual mean and the sum of absolute residual.
The present study was performed to investigate whether breast-feeding is associated with early pubertal development among children 7–9 years old in Korea.
Children were divided into those who did and did not receive breast-feeding for 6 months or longer in accordance with the recommendations of the WHO. Pubertal status was determined by clinical examination using Tanner staging.
Prospective observational study.
We conducted a follow-up study of children aged 7–9 years in 2011 who had taken part in the Ewha Birth & Growth Cohort study.
Fifty (22·8 %) of the total of 219 children were in early puberty, with the proportion being slightly higher for girls (24·1 %) than boys (21·4 %). Children who had entered early puberty were taller, weighed more and had a higher concentration of insulin-like growth factor 1. Moreover, the change in weight Z-score from birth to follow-up was significantly lower in children who were breast-fed than in those who were not (weight Z-score change: 0·32 (sd 1·59) v. 0·77 (sd 1·61), respectively, P=0·04). Comparison of breast-feeding by puberty status indicated a preventive association with early puberty in children who were breast-fed for 6 months or longer (OR=0·37; 95 % CI 0·18, 0·74). This association remained significant after adjustment for relevant covariates.
These results demonstrate a beneficial association between breast-feeding and early pubertal development, especially in those breast-fed for 6 months or longer. The study suggests that interventions would need to start early in life to prevent early pubertal development.
In this paper, we study adaptive nonparametric regression estimation in the presence of conditional heteroskedastic error terms. We demonstrate that both the conditional mean and conditional variance functions in a nonparametric regression model can be estimated adaptively based on the local profile likelihood principle. Both the one-step Newton–Raphson estimator and the local profile likelihood estimator are investigated. We show that the proposed estimators are asymptotically equivalent to the infeasible local likelihood estimators [e.g., Aerts and Claeskens (1997) Journal of the American Statistical Association 92, 1536–1545], which require knowledge of the error distribution. Simulation evidence suggests that when the distribution of the error term is different from Gaussian, the adaptive estimators of both conditional mean and variance can often achieve significant efficiency over the conventional local polynomial estimators.