Objective To investigate whether screening for thyroid cancer led to the current “epidemic” in South Korea.Design Review of the medical records of nationally representative samples of patients with a ...diagnosis of thyroid cancer in 1999, 2005, and 2008.Setting Sample cases were randomly selected from South Korea’s nationwide cancer registry, using a systematic sampling method after stratification by region.Participants 5796 patients with thyroid cancer were included (891 in 1999, 2355 in 2005, and 2550 in 2008).Main outcome measures The primary outcome was age standardised incidence of thyroid cancer and the changes in incidence between 1999 and 2008 according to the methods used to detect tumours (screen detection versus clinical detection versus unspecified).Results Between 1999 and 2008, the incidence of thyroid cancer increased 6.4-fold (95% confidence interval 4.9-fold to 8.4-fold), from 6.4 (95% confidence interval 6.2 to 6.6) per 100 000 population to 40.7 (40.2 to 41.2) per 100 000 population. Of the increase, 94.4% (34.4 per 100 000 population) were for tumours less than 20 mm, which were detected mainly by screening. 97.1% of the total increase was localised and regional tumours according to the Surveillance, Epidemiology, and End Results (SEER) summary stage. Where cases were clinically detected, 99.9% of the increased incidences (6.4 per 100 000 population) over the same period were tumours less than 20 mm.Conclusion The current “epidemic” of thyroid cancer in South Korea is due to an increase in the detection of small tumours, most likely as a result of overdetection. Concerted efforts are needed at a national level to reduce unnecessary thyroid ultrasound examinations in the asymptomatic general population.
Hybrid electric vehicle (HEV) technology provides an effective solution for achieving higher fuel economy, better performance, and lower emissions, compared with conventional vehicles. Plug-in HEVs ...(PHEVs) are HEVs with plug-in capabilities and provide a more all-electric range; hence, PHEVs improve fuel economy and reduce emissions even more. PHEVs have a battery pack of high energy density and can run solely on electric power for a given range. The battery pack can be recharged by a neighborhood outlet. In this paper, a novel integrated bidirectional AC/DC charger and DC/DC converter (henceforth, the integrated converter) for PHEVs and hybrid/plug-in-hybrid conversions is proposed. The integrated converter is able to function as an AC/DC battery charger and to transfer electrical energy between the battery pack and the high-voltage bus of the electric traction system. It is shown that the integrated converter has a reduced number of high-current inductors and current transducers and has provided fault-current tolerance in PHEV conversion.
With the requirements for reducing emissions and improving fuel economy, automotive companies are developing electric, hybrid electric, and plug-in hybrid electric vehicles. Power electronics is an ...enabling technology for the development of these environmentally friendlier vehicles and implementing the advanced electrical architectures to meet the demands for increased electric loads. In this paper, a brief review of the current trends and future vehicle strategies and the function of power electronic subsystems are described. The requirements of power electronic components and electric motor drives for the successful development of these vehicles are also presented.
Abstract
For steady electroconversion to value-added chemical products with high efficiency, electrocatalyst reconstruction during electrochemical reactions is a critical issue in catalyst design ...strategies. Here, we report a reconstruction-immunized catalyst system in which Cu nanoparticles are protected by a quasi-graphitic C shell. This C shell epitaxially grew on Cu with quasi-graphitic bonding via a gas–solid reaction governed by the CO (g) - CO
2
(g) - C (s) equilibrium. The quasi-graphitic C shell-coated Cu was stable during the CO
2
reduction reaction and provided a platform for rational material design. C
2+
product selectivity could be additionally improved by doping
p
-block elements. These elements modulated the electronic structure of the Cu surface and its binding properties, which can affect the intermediate binding and CO dimerization barrier. B-modified Cu attained a 68.1% Faradaic efficiency for C
2
H
4
at −0.55 V (vs RHE) and a C
2
H
4
cathodic power conversion efficiency of 44.0%. In the case of N-modified Cu, an improved C
2+
selectivity of 82.3% at a partial current density of 329.2 mA/cm
2
was acquired. Quasi-graphitic C shells, which enable surface stabilization and inner element doping, can realize stable CO
2
-to-C
2
H
4
conversion over 180 h and allow practical application of electrocatalysts for renewable energy conversion.
A simple and environmentally friendly method for the preparation of composite cathode materials from cost‐effective waste‐product elemental sulfur and sustainable, nonhazardous vegetable oils is ...presented. High sulfur contents of up to 80 wt% are achieved. Scanning electron microscopy reveals that the composite materials consist of micrometer sized sulfur particles which are embedded in a crosslinked polymeric network. The polymeric network formed upon copolymerization of the fatty acid residues and elemental sulfur is similar to factice. For the first time factice‐like sulfur containing composites are utilized successfully as the active cathode material in Li–S batteries. Upon employment, high initial specific capacities up to 880 mAh g−1, good capacity retention abilities (63% after 100 cycles) as well as high coulombic efficiencies are achieved, suggesting reasonable suppression of polysulfide diffusion as a consequence of the embedment.
High‐sulfur content composite materials consisting of sulfur microparticles inside a copolymeric network can be prepared from cost‐effective waste‐product elemental sulfur and sustainable, nonhazardous vegetable oils in a simple one‐pot procedure and utilized as active material in lithium‐sulfur batteries yielding good capacity retention.
Development of advanced motor drives has yielded increases in efficiency and reliability. Residential and commercial appliances such as refrigerators and air conditioning systems use conventional ...motor drive technology. The machines found in these applications are characterized by low efficiency and high maintenance. A brushless dc (BLDC) motor drive is characterized by higher efficiency, lower maintenance, and higher cost. In a market driven by profit margins, the appliance industry is reluctant to replace the conventional motor drives with the advanced motor drives (BLDC) due to their higher cost. Therefore, it is necessary to have a low-cost but effective BLDC motor controller. This paper lays the groundwork for the development of a new low-cost IC for control of BLDC motors. A simple novel digital pulsewidth-modulation control has been implemented for a trapezoidal BLDC motor drive system. Due to the simplistic nature of this control, it has the potential to be implemented in a low-cost application-specific integrated circuit. The novel controller is modeled and verified using simulations. Experimental verification is carried out using field-programmable gate arrays to validate the claims presented.
This study reports the cancer statistics and temporal trends in Korea on a nationwide scale, including incidence, survival, prevalence, and mortality in 2017.
The incidence, survival, and prevalence ...rates of cancer were evaluated using data from the Korea National Cancer Incidence Database from 1999 to 2017 with follow-up until December 31, 2018. Deaths from cancer were assessed using cause-of-death data from 1983 to 2017, obtained from Statistics Korea. Crude and age-standardized rates (ASRs) for incidence, mortality, and prevalence, and 5-year relative survival rates were calculated and trend analysis was performed.
In 2017, newly diagnosed cancer cases and deaths from cancer numbered 232,255 (ASR, 264.4 per 100,000) and 78,863 (ASR, 76.6 per 100,000), respectively. The overall cancer incidence rates increased annually by 3.5% from 1999 to 2011 and decreased by 2.7% annually thereafter. Cancer mortality rates have been decreasing since 2002, by 2.8% annually. The 5-year relative survival rate for all patients diagnosed with cancer between 2013 and 2017 was 70.4%, which contributed to a prevalence of approximately 1.87 million cases by the end of 2017.
The burden of cancer measured by incidence and mortality rates have improved in Korea, with the exception of a few particular cancers that are associated with increasing incidence or mortality rates. However, cancer prevalence is increasing rapidly, with the dramatic improvement in survival during the past several years. Comprehensive cancer control strategies and efforts should continue, based on the changes of cancer statistics.
Aim
To provide in‐depth understanding of real‐world tumor necrosis factor inhibitor (TNFi) treatment patterns in patients with ankylosing spondylitis (AS) and treatment satisfaction, productivity ...loss, and associated factors.
Methods
This was a multicenter observational hybrid retrospective chart review and cross‐sectional survey study. Disease activity and physical functioning were measured using the Bath AS Disease Activity Index and Bath AS Functional Index, respectively. Treatment satisfaction was determined with the Treatment Satisfaction Questionnaire for Medication (TSQM). Productivity loss was evaluated using the Korean version of the World Health Organization–Health and Work Performance Questionnaire.
Results
A total of 497 patients were enrolled (mean age 40.3 years, 85.3% male, mean AS duration 10 years). The mean duration of TNFi treatment was 6.2 years. Among the four TNFi considered, adalimumab (39.6%) and etanercept (23.5%) were most commonly used at study enrollment. The TSQM convenience domain score was lower than scores in the effectiveness, adverse effects, and global satisfaction domains. Subcutaneous syringe‐type injection and intravenous injection were associated with lower patient convenience satisfaction than subcutaneous pen‐type injection. Increased costs of lost productivity time were associated with female sex, unemployed status, and higher disease activity.
Conclusions
The most frequently prescribed TNFi was adalimumab, followed by etanercept. Etanercept was used for the longest duration. More convenient treatment options may enhance overall treatment satisfaction. Considerable loss in productivity due to AS was observed in this study. To reflect patients’ perspectives, further attention should be paid to factors associated with treatment satisfaction and productivity loss when selecting treatment options.
The distinguishing feature of a flexible electronic device is that it maintains its function even when the shape changes repeatedly. As the degree of integration of flexible devices increases, ...revealing failure mechanisms and extending the lifetime of the flexible devices are getting more difficult. One of the potential damage zones is the interface of heterogeneous material components, where strain can be localized due to the mismatch of mechanical properties. In this study, we investigate the mechanically reliable interconnect design of the flexible printed circuit board (FPCB) system in which the packaging chip is integrated. When the FPCB was bent, folding occurred at the edge of the packaging chip due to the high bending rigidity compared with the plastic substrate and resulted in high strain concentration. By introducing interconnect architecture that bypassed the strain concentration area around the packaging chip, mechanical damage of the interconnects was successfully reduced. Through finite element simulation, the strain applied to the interconnect crossing the strain-concentrated region was predicted to be 2 times larger than that bypassing the strain-concentrated region, from 8.32 to 4.64%. In addition, the strain gap of these two interconnects could be increased as the Young’s modulus mismatch between the packaging chip and the substrate increased. This study is expected to improve the design guidelines to mechanically reliable interconnects in highly integrated flexible electronics.
Graphical Abstract
A mechanochromic strain sensor that is capable of distinguishing the orientation, the location, and the degree of deformation based on the highly stretchable membrane of main‐chain chiral liquid ...crystalline elastomer (MCLCE) is proposed. The MCLCE film is designed to exhibit uniform and significant color shift upon the small strain by using step‐growth polymerization of liquid crystal (LC) oligomer and its phase‐stabilization in solvent mesogen. As conformally placed on the bottom elastomer sheet, the MCLCE film shows multimodal, instantaneous color change for sensing arbitrary in‐plane deformation, out‐of‐plane bending, and nonzero Gaussian deformation. Based on high freedom in the device design, it is also demonstrated that this sensor can display color patterns or encrypted images in response to the localized weight or strain. The simple and straightforward concept proposed here can be applicable in the fields of wearable devices, displays, and soft robotics.
Main‐chain chiral liquid crystalline elastomer membrane can simultaneously differentiate the types, degrees, and directions of deformations in the supporting layers, including in‐ and out‐of‐plane bending and nonzero Gaussian strains. New types of mechanochromic applications such as strain‐optic scale, strain‐display, and strain detectable encryption are demonstrated.
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