Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major public health concern. However, its relationship with the long-term mortality risk remains underexplored in the general population. We aimed to examine the association between liver fibrosis, assessed using the age-adjusted Fibrosis-4 (FIB-4) residual index, and all-cause and cardiovascular mortality in individuals with MASLD. This cohort study included 134,686 adults diagnosed with MASLD via ultrasonography and metabolic abnormalities during health screenings at two Korean centers between 2002 and 2022. The participants were followed up for mortality outcomes using the National Death Registry. The FIB-4 index was calculated from age, AST, ALT, and platelet count adjusted for age using residual modeling. Cox proportional hazards models were used to estimate the hazard ratios (HRs) for all-cause and cardiovascular mortality, adjusting for sociodemographic, behavioral, and clinical covariates. Age-stratified analyses were also performed. During a mean follow-up of 11.2 years, 2,129 all-cause and 348 cardiovascular deaths occurred. A higher age-adjusted FIB-4 index was associated with increased risk of all-cause mortality (HR 1.489, 95% CI 1.353-1.639) and cardiovascular mortality (HR 1.478, 95% CI 1.175-1.860). These associations persisted after adjustment. In stratified analyses, all-cause mortality associations were significant in both age groups, whereas cardiovascular mortality was significant only in those aged > 39 years. The age-adjusted FIB-4 index was independently associated with increased risk of all-cause and cardiovascular mortality in patients with MASLD. Assessing liver fibrosis using FIB-4 may provide prognostic information beyond traditional cardiometabolic risk factors in this population.
Background:Despite hearing loss being a prevalent chronic condition, estimated to nearly 20% of the global population by the World Health Organization, the specific association with individual lifestyle factors, particularly alcohol consumption, remains unclear. In South Korea, approximately 80% of the population engages in alcohol consumption, with a notably high prevalence among males, indicating a high-risk drinking pattern. Therefore, this study aimed to assess the correlation between alcohol consumption and hearing loss in male workers, as well as to analyze additional variables such as alcohol flushing reaction, with the intention of improving worker health.Methods:The study was conducted from January 2012 to December 2019, targeting 114,114 participants who visited Kangbuk Samsung Hospital Total Healthcare Centers. Data were collected through pure-tone audiometry tests and alcohol-related questionnaire, and statistical analysis was performed using Cox regression analysis. Based on previous studies indicating a potential protective effect of light drinking on hearing loss, this group was designated as the reference. Additionally, stratified analyses were conducted based on the presence of alcohol flushing reaction and different working hours.Results:The hazard ratio (95% confidence interval) for hearing loss was higher in the heavy drinking group (1.23 [1.11-1.37]) compared to the moderate drinking group (1.09 [0.98-1.20]). Stratified analyses revealed a significantly elevated the hazard ratio of hearing loss in groups with alcohol flushing reaction compared to those without this factor.Conclusions:Our study demonstrated that moderate or heavy alcohol consumption in male workers can increase the risk of hearing loss, particularly in those with alcohol flushing reaction. These findings underscore the importance of addressing alcohol-related factors concerning hearing health among male workers.
This paper presents a wideband low-profile dual-polarized patch antenna with helical-shaped L-probe feeding (HLF) for mmWave 5G mobile device applications. Parametric studies on the HLF structure are performed to identify the optimal specifications. As a result, the optimized antenna achieves a wide bandwidth of 5.4 GHz (24.2–29.6 GHz), good isolation > 18 dB between ports, and 5.1 dBi of good peak realized gain, which is experimentally verified with a 10× upscaled antenna. In addition, various one × four phased arrays with different port configurations and beamform capabilities are designed and simulated for the peak realized gain. The designed antenna array shows a high peak realized gain of 10 dBi, high isolation of 15 dB between the ports, and a small substrate thickness of 0.048λ0 (λ0 is the wavelength of 24.25 GHz). Compared to the state-of-the-art antennas, the designed dual-polarized antenna can operate in the frequency ranges of 24.25–29.6 GHz, including n257, n258, and n261 of the 5G new radio frequency range 2.
Non-alcoholic fatty liver disease (NAFLD) is a relatively common disease, and preventing its occurrence is important for both individual health and reducing social costs. Shift work is reported to have several negative effects on health. An association has been observed between NAFLD and both sleep time and quality; however, this association remains unclear in night shift workers. We aimed to evaluate the relationship between shift work and the incidence of NAFLD. Overall, 45,149 Korean workers without NAFLD were included at baseline. NAFLD was defined as the presence of a fatty liver observed on ultrasonography without excessive alcohol use. incidence rate ratios for incident NAFLD were estimated using negative binomial regression according to age groups (20s, 30s, 40s, and 50s). In the 20s age group, shift work showed a significant incidence rate ratio (IRR) for NAFLD in all models. After adjusting for all variables, the IRR (95% confidence interval) was 1.24 (1.08-1.43) in the 20s age group. In their 20s, a significant association between shift work and incident NAFLD was consistently observed among women and workers with poor sleep quality. In this large-scale cohort study, shift work was significantly associated with the development of NAFLD among young workers in their 20s.
This study aimed to identify the major industries and jobs with the highest proportion of workers' compensation (WC) claims for COVID-19, characterize COVID-19 WC claims in terms of their demographic properties and disease severity, and identify factors influencing the approval of COVID-19 WC claims as occupational disease. A total of 488 workers who submitted COVID-19-related claims to the Korea Workers' Compensation and Welfare Service (KWCWS) from January 2020 to July 2021 were analyzed. A Fisher's exact test was employed to associate the severity of COVID-19 infection with demographic properties. The highest proportion of all COVID-19 WC claims compensated as occupational disease (N=462) were submitted by healthcare workers (HCW=233, 50%), while only 9% (N=41) of the total originated from manufacturing industries. The 5% (N=26) of the COVID-19 WC claims accepted were evaluated as severe (N=15) and acute respiratory distress syndrome (N=9). A total of 71% (N=329) of the COVID-19 patients compensated (N=462) were from workplaces with infection clusters. A total of 26 WC cases were rejected for various reasons, including unclear infection routes, infection at private gatherings (including within families), no diagnosis, and more. Given our findings, we suggest an official system should be established to detect and compensate more job-associated infectious diseases like COVID-19.
Tuning of the magnetocrystalline anisotropy of MnAl was studied by substituting Mn of MnAl with transition elements (Fe, Co, or Ni). The Brillouin function and semi-empirical Callen and Callen relation predicted the thermal behaviors of saturation magnetization and magnetocrystalline anisotropy energy. First-principles calculations based on density functional theory (DFT) were performed to calculate the electronic structures of Mn0.5TM0.5Al, where TM = Mn, Fe, Co, and Ni. The estimated total magnetic moment of Mn0.5TM0.5Al decreases as the number of valence electrons (n) of TM (e.g., 7 for Mn (3d5 4 s2), 8 for Fe (3d6 4 s2), 9 for Co (3d7 4 s2), and 10 for Ni (3d8 4 s2)) increases. Ni-substituted MnAl becomes ferrimagnetic, while other TM-substituted MnAl retain a ferromagnetic state. Curie temperature rapidly decreases with increasing the valence electrons from 685 K for MnAl to 20 K for Ni-substituted MnAl. Thermomagnetic behaviors of Mn0.5TM0.5Al (TM = Mn, Fe, Co, or Ni) are reported. Our magnetocrystalline anisotropy energy (MAE) calculations demonstrate that the magneto crystalline anisotropy changes to the in-plane from the out-of-plane (uniaxial) direction for Co- and Nisubstituted MnAl. The K reaches a maximum of 2.98 MJ/m3 at n = 8, i.e., Fe substitution.
Background: Hearing loss (HL) is linked to an elevated risk of cardiovascular diseases (CVDs). The pathogeneses of HL and CVD commonly involve inflammatory responses. Previous studies investigated elevated levels of inflammatory biomarkers in subjects with HL, however, their findings did not demonstrate statistical significance. In our cross-sectional and longitudinal study, we investigated the correlation between HL and increased high sensitivity C-reactive protein (hsCRP) levels to determine how HL is associated with CVDs.Methods: We conducted a cross-sectional study with workers aged over 18 years who underwent health check-ups at our institution between 2012 and 2018 (n = 566,507), followed by conducting a longitudinal study of workers aged > 18 who underwent health checkups at least twice at our institution between 2012 and 2018 (n = 173,794). The definition of HL was as an average threshold of >= 20 dB in pure-tone air conduction at 0.5, 1.0, and 2.0 kHz in both ears. The incidence of increased hsCRP levels throughout the follow-up period was defined as a level exceeding 3 mg/L. Logistic regression and generalized estimating equations were performed to estimate the risk of increased hsCRP levels according to the occurrence of HL in groups stratified by age.Results: In the cross-sectional study, the multivariate-adjusted odds ratio (OR) was 1.17 (95% confidence interval [CI]: 1.02-1.34); the OR was 0.99 (95% CI: 0.80-1.22) in those under 40 and 1.28 (1.08-1.53) in those over 40. In the longitudinal study, the multivariable-adjusted OR was 1.05 (95% CI: 0.92-1.19); the OR was 1.10 (95% CI: 0.90-1.35) in those under 40 and 1.20 (1.01-1.43) in those over 40.Conclusions: This cross-sectional and longitudinal study identified an association between HL and increased hsCRP levels in workers aged over 40 years.
Shift work has adverse health effects such as diabetes, cardiovascular disease, sleep disturbance, depression, and breast cancer. Gastro-esophageal reflux disease (GERD) results in lesions such as reflux esophagitis (RE) and Barrett’s esophagus. This study investigated the association between shift work and RE. A cohort study was conducted with 140,553 participants who were followed up at least once from 2012 to 2018. Type of working and shift types were collected using standardized questionnaires. Esophagogastroduodenoscopy (EGD) was performed by experienced endoscopists who were blinded to the aims of this study. According to the Los Angeles classification, RE was categorized based on the extent of esophageal mucosal breaks. During the 469,217.2 person-years of follow-up, 35,185 participants developed incident cases of RE. The multivariable adjusted hazard ratio (95% confidence intervals) for incident cases comparing shift work to fixed day work was 1.09 (1.04–1.13). This association was more strongly observed in the younger age group (18–39 years old) and the female group. In conclusion, shift work was significantly associated with the incidence of RE. Particularly, the results were more significant in the younger and female groups.
low-power DRAM controller ASIC is proposed for point-to-point interconnects such as deep learning applications. The termination resistance of the DRAM controller is increased to 160 omega and infinity during the write and read modes, respectively, to reduce power consumption with no transmission errors. Short-reach interconnects of 25 mm DQ/DQS lines are used to avoid signal integrity issues. The proposed DRAM controller is implemented in a 65 nm process with an active area of 1.64 mm2, 16 DQ 8 Gb configuration, and a data rate of 800 Mbps per DQ pin. The DRAM interface using the proposed controller and a commercial DDR3 DRAM chip consumes 379 mW on average; this is 64% of the power with the default termination of the JEDEC standard. Derived equations for the TX and RX current of the DRAM interface reveals that the TX current of a clock signal is minimized when the time of flight of the PCB channel is integer multiples of the half period of the clock signal with large TX and RX terminations.
First-principles calculations were performed to calculate the electronic structures of low temperature phase (LTP) MnBi (Mn50Bi50) and substitutionally and interstitially Sn-doped MnBi [Mn50Bi25Sn25, (Mn0.5Bi0.5)66.7Sn33.3]. Brillouin function predicts the temperature dependence of saturation magnetization M(T). Sn substitution for Bi in MnBi (Mn50Bi25Sn25) changes the magnetocrystalline anisotropy constant (Ku) from −0.202 MJ/m3 (the in-plane magnetization) for LTP MnBi to 1.711 MJ/m3 (the out-of-plane magnetization). In comparison, the Ku remains negative but slightly decreases to −0.043 MJ/m3 when Sn is interstitially doped in MnBi [(Mn0.5Bi0.5)66.7Sn33.3]. The Curie temperature (TC) decreases from 716 K for LTP Mn50Bi50 to 445 K for Mn50Bi25Sn25 and 285 K for (Mn0.5Bi0.5)66.7Sn33.3. Mn50Bi25Sn25 has a lower magnetic moment of 5.034 μB/f.u. but a higher saturation magnetization of 64.2 emu/g than (Mn0.5Bi0.5)66.7Sn33.3 with a magnetic moment of 6.609 μB/f.u. and a saturation magnetization of 48.2 emu/g because the weight and volume of the substitutionally Sn-doped MnBi are smaller than the interstitially Sn-doped MnBi. The low Curie temperature and magnetization for Sn-doped MnBi are attributed to the high concentration of Sn. Thus, future study needs to focus on low Sn-concentrated MnBi.
Spoke-type PMSMs were designed with commercial permanent magnets and theoretically designed hexaferrite: Nd-Fe-B (NdFe35, G1NH), Alnico (8B, 8H, 9), and La-CoSrM hexaferrite (NMF-15G). It was found that coercivity (H c ) plays a crucial role in determining motor performance. The ANSYS Maxwell software was used to characterize the designed motor performance. Commercial RE-free Alnico 9 holds a 10.5 MGOe of (BH) max , much higher than a 5.5 MGOe of RE-free Alnico 8B/8H and SrM (SrFe 12 O 19 ) hexaferrite magnets. However, the Alnico 9 motor performance is not better than the other Alnico 8B/8H and hexaferrite motors. The spoke-type PMSM with our theoretically designed SrM hexaferrite simulated motor performance. A motor performs best when the H c /B r ratio equals one with a high H c . For instance, the motor torque and peak power increase to 189 Nm and 178 kW, respectively, as the H c increases to 4.86 kOe from 2.43 kOe. However, the motor performance is not significantly changed with a fixed H c and various B r . It was found that regardless of (BH) max , coercivity (H c ) plays a dominant role in motor performance.
This paper presents a novel high-gain, miniaturized, and ultra-wideband tapered-slot Vivaldi antenna (TSVA) for ice-sounding radar applications. To miniaturize the antenna and improve the impedance matching and antenna gain of conventional TSVA, tapered slot edge, circular cavity, rectangular cavity, inner circular patch, and rectangular slit structures are newly designed and introduced. The simulation results show that the size of the designed Vivaldi antenna is reduced by 15% and increases the peak realized gain by up to 5.1 dBi, compared to the conventional Vivaldi antenna. The optimized Vivaldi antenna was fabricated and characterized for its antenna performance. The simulated results are in good agreement with the measured results.
INTRODUCTION Occupational health nurses (OHNs) in South Korea who visit the workplace periodically could play a key role in smoking cessation. It would be helpful to assess their understanding of smoking hazards and smoking cessation methods to encourage them to provide smoking intervention services at the workplace. This study aimed to investigate the knowledge of smoking hazards and perceptions of smoking cessation methods among OHNs.METHODS We conducted an anonymous self-administered cross-sectional questionnaire survey of 108 OHN nurses employed in an occupational health service outsourcing specialized agency with 19 regional branches in Korea from July to August 2019. We assessed the perceptions of the OHNs about smoking interventions, hazards of smoking, and perceived competence to counsel smokers according to training experience, using chi-squared tests and Fisher's exact tests.RESULTS The majority of the nurses underestimated the smoking-attributable fraction for lung cancer (78.7%), chronic obstructive pulmonary disease (64.8%), and mortality (49.0%), regardless of training experience on smoking cessation, while more than half perceived their skill and knowledge to counsel patients concerning smoking as inadequate (56.5%). However, those trained in smoking cessation interventions felt more competent in smoking cessation counselling, with 52.2% and 29.3% in the trained and non-trained groups, respectively (p=0.019).CONCLUSIONS The OHNs in this study underestimated smoking hazards and perceived themselves as lacking counselling skills regarding smoking cessation interventions. It is necessary to encourage OHNs to promote smoking cessation by increasing their knowledge, skills and competence in smoking cessation interventions.
Background: Shift work has been reported to have several harmful effects on the human body. However, a small number of studies have evaluated the association between shift work and adverse effects on the thyroid. In our longitudinal study, we examined the causal association between shift work and the risk of hypothyroidism.Methods: A Kangbuk Samsung Cohort Study was conducted on 112,648 men without thyroid disease at baseline who were followed up at least once between 2012 and 2019. Shift work status and shift schedule types were categorized using standardized questionnaires. Hypothyroidism was defined using the reference ranges of serum thyroid-stimulating hormones and free thyroxine levels. Hazard ratios (HRs) and 95% confidence intervals (CIs) for incident hypothyroidism were estimated using Cox proportional hazards regression analyses with the daytime work group as the reference.Results: During the 501,237 person-years of follow-up, there were 6,306 incident cases of hypothyroidism (incidence density, 1.26 per 100 person-years). The multivariable-adjusted HR of incident hypothyroidism for the shift work total group that included all shifts compared with the daytime work group was 1.27 (95% CI: 1.15-1.40). For the fixed evening, fixed night, rotating shift, and other shift workers, the multivariable-adjusted HRs (95% CI) were 1.11 (0.76-1.61), 2.18 (1.20-3.93), 1.39 (1.23-1.56), and 1.00 (0.82-1.22), respectively. In subgroup analyses by age, the association between shift work and hypothyroidism was more pronounced in younger participants (< 40 years; HR: 1.31; 95% CI: 1.16-1.47).Conclusions: Our large-scale cohort study showed an association between shift work and the incidence of hypothyroidism, especially in younger workers with night shifts.
77 Kelvin, it was found that the weak cells with large gate-induced drain leakage current are quite localized in six weak rows out of the entire 524,288 rows of a 8 Gb DRAM chip. By replacing the six weak rows, the DRAM retention time was increased from 8 to 4096 seconds at 77 Kelvin. Because this retention time is over 64,000 times longer than the JEDEC retention-time specification of 0.064 seconds, the DRAM refresh power can be reduced to a negligible level at the data center. To achieve this, the DRAM controller was modified to find weak rows by using three different data patterns at power-on reset and a reserved row of DRAM is used when access to a weak row address occurs during the normal operation.
Long working hours have negative effects on the health of workers. Several studies have reported the association between long working hours and both diabetes and prediabetes. Therefore, we aimed to examine the temporal relationship between long working hours and glucose intolerance. Our cohort study collected data from 25,803 healthy male participants at baseline. To evaluate the risk of incident glucose intolerance, we estimated the hazard ratios (HRs) and 95% confidence intervals (CIs) using the Cox proportional hazards regression analyses. During 77,605.0 person-years of follow-up, 6741 participants developed glucose intolerance. Multivariable-adjusted HRs (95% CI) for weekly working 41–52 and >52 h compared with working 35–40 h, were 1.28 (1.17–1.40) and 2.80 (2.54–3.09), respectively. In the dose-response analyses, long working hours had a nearly linear relationship with the development of glucose intolerance across most working hours per week. The association between long working hours and incident glucose intolerance was stronger in the younger-age subgroups than in the older-age subgroups (p for interaction <0.001). Our large-scale cohort study demonstrated that long working hours were associated with incident glucose intolerance, with a dose-response relationship.
Background: According to the occupational accident status analysis in 2020, of 1,180 occupational deaths, 463 were caused by cardiovascular disease (CVD). Workers should be assessed for CVD risk at regular intervals to prevent work-related CVD in accordance with the rules on occupational safety and health standards. However, no previous study has addressed risk and mortality. Therefore, this longitudinal study was conducted to evaluate the relationship between 10-year cardiovascular risk of the general health checkup and mortality. Methods: The study included 545,859 participants who visited Kangbuk Samsung Total Healthcare Centers from January 1, 2002, to December 31, 2017. We performed 10-year cardiovascular risk assessment for the participants and the risk was divided into 4 groups (low, moderate, high, and very high). The study used death data from the Korea National Statistical Office for survival status as an outcome variable by December 31, 2019, and the cause of death based on the International Classification of Diseases, 10th Revision (ICD-10) was identified. Statistical analysis was performed using Cox proportional hazards regression analysis, and the sum of the periods from the first visit to the date of death or December 31, 2019, was used as a time scale. We also performed a stratified analysis for age at baseline and sex. Results: During 5,253,627.9 person-years, 4,738 overall deaths and 654 cardiovascular deaths occurred. When the low-risk group was set as a reference, in the multivariable-adjusted model, the hazard ratios (HRs) (95% confidence interval [CI]) for overall mortality were 3.36 (2.87-3.95) in the moderate-risk group, 11.08 (9.27-13.25) in the high-risk group, and 21.20 (17.42-25.79) in the very-high-risk group, all of which were statistically significant. In cardiovascular deaths, the difference according to the risk classification was more pronounced. The HRs (95% CI) were 8.57 (4.95-14.83), 38.95 (21.77-69.69), and 78.81 (42.62- 145.71) in each group. As a result of a subgroup analysis by age and sex, the HRs of all-cause mortality and cardiovascular mortality tended to be higher in the high-risk group. Conclusions: This large-scale longitudinal study confirmed that the risk of death increases with the 10-year cardiovascular risk of general health checkup.
This paper presents a low-latency streaming on-device automatic speech recognition system for inference. It consists of a hardware acoustic model implemented in a field-programmable gate array, coupled with a software language model running on a smartphone. The smartphone works as the master of the automatic speech recognition system and runs a three-gram language model on the acoustic model output to increase accuracy. The smartphone calculates and sends the Mel-spectrogram of an audio stream with 80 ms unit input from the built-in microphone of the smartphone to the field-programmable gate array every 80 ms. After ~35 ms, the field-programmable gate array sends the calculated word-piece probability to the smartphone, which runs the language model and generates the text output on the smartphone display. The worst-case latency from the audio-stream start time to the text output time was measured as 125.5 ms. The real-time factor is 0.57. The hardware acoustic model is derived from a time-depth-separable convolutional neural network model by reducing the number of weights from 115 M to 9.3 M to decrease the number of multiply-and-accumulate operations by two orders of magnitude. Additionally, the unit input length is reduced from 1000 ms to 80 ms, and to minimize the latency, no future data are used. The hardware acoustic model uses an instruction-based architecture that supports any sequence of convolutional neural network, residual network, layer normalization, and rectified linear unit operations. For the LibriSpeech test-clean dataset, the word error rate of the hardware acoustic model was 13.2% and for the language model, it was 9.1%. These numbers were degraded by 3.4% and 3.2% from the original convolutional neural network software model due to the reduced number of weights and the lowering of the floating-point precision from 32 to 16 bit. The automatic speech recognition system has been demonstrated successfully in real application scenarios.
Objective This study aimed to evaluate the relationship between working hours and glycemic control. Methods Study was performed among Korean participants who underwent at least two health screening examinations between 2012 and 2018. The study included 2169 participants who were older than 40 years and undergoing treatment for diabetes at baseline. A hemoglobin A1c level >9% at the follow-up visit was defined as poor glycemic control. The weekly working hours were divided into three groups for analysis. Results Compared with participants with 45–54 weekly working hours, multivariate-adjusted hazard ratios (95% confidence intervals) for incident poor glycemic control among participants with ≥55 and 35–44 working hours were 1.40 (1.01–1.96) and 1.51 (1.09–2.09), respectively. Conclusions Standard working hours and long working hours were independent risk factors for poor diabetes control in patients with diabetes.