Additional surgeries for implantable biomedical devices are inevitable to replace discharged batteries, but repeated surgeries can be a risk to patients, causing bleeding, inflammation, and ...infection. Therefore, developing self‐powered implantable devices is essential to reduce the patient's physical/psychological pain and financial burden. Although wireless communication plays a critical role in implantable biomedical devices that contain the function of data transmitting, it has never been integrated with in vivo piezoelectric self‐powered system due to its high‐level power consumption (microwatt‐scale). Here, wireless communication, which is essential for a ubiquitous healthcare system, is successfully driven with in vivo energy harvesting enabled by high‐performance single‐crystalline (1 − x)Pb(Mg1/3Nb2/3)O3−(x)Pb(Zr,Ti)O3 (PMN‐PZT). The PMN‐PZT energy harvester generates an open‐circuit voltage of 17.8 V and a short‐circuit current of 1.74 µA from porcine heartbeats, which are greater by a factor of 4.45 and 17.5 than those of previously reported in vivo piezoelectric energy harvesting. The energy harvester exhibits excellent biocompatibility, which implies the possibility for applying the device to biomedical applications.
In vivo self‐powered wireless transmission using a flexible single‐crystalline piezoelectric energy harvester is demonstrated. The high‐performance energy harvester generates an output voltage of 17.8 V and a current of 1.75 µA from the contraction and relaxation motion of porcine heart. The energy from in vivo physiological motion enables self‐powered wireless transmission, thus realizing practical application in the ubiquitous healthcare system.
This study examined complex structural relationships among different organizational constructs affecting organizational performance at the individual level, which included psychological- ...(meaningfulness and work engagement), behavioural- (in-role performance), and situational- (job characteristics) constructs. Using a conditional process model, the current study investigated how the relationship between meaningfulness and in-role performance, mediated by work engagement, is also affected by job characteristics. Data were collected from 309 employees working at South Korean IT firms using a survey questionnaire. Study findings highlight that (a) meaningfulness is positively related to work engagement and in-role performance; (b) work engagement mediates the relationship between meaningfulness and in-role performance; (c) the relationship between meaningfulness and work engagement is moderated by job characteristics; and (d) the indirect relationship between meaningfulness and in-role performance through work engagement is associated with the level of job characteristics. This study contributes to the HRD literature on work engagement by providing evidence of complicated structural relationships among these organizational constructs. Also, these findings deepen the understanding of HRD scholars and managers in organizations and provide suggestions regarding how they can further investigate and implement work engagement in relation to job characteristics to improve individual job performance.
Owing to the limited electrochemical stability window of carbonate electrolytes, the initial formation of a solid electrolyte interphase and surface film on the negative and positive electrode ...surfaces by the decomposition of the electrolyte component is inevitable for the operation of lithium secondary batteries. The deposited film on the surface of the active material is vital for reducing further electrochemical side reactions at the surface; hence, the manipulation of this formation process is necessary for the appropriate operation of the assembled battery system. In this study, the thermal decomposition of LiPF6 salt is used as a surface passivation agent, which is autocatalytically formed during high‐temperature storage. The thermally formed difluorophosphoric acid is subsequently oxidized on the partially charged high‐Ni positive electrode surface, which improves the cycleability of lithium metal cells via phosphorus‐ and fluorine‐based surface film formation. Moreover, the improvement in the high‐temperature cycleability is demonstrated by controlling the formation process in the lithium‐ion pouch cell with a short period of high‐temperature storage before battery usage.
Positive electrode surface is reinforced by additive‐free carbonate electrolyte by short‐period thermal exposure of the electrode at a high state‐of‐charge from thermoelectrochemical oxidation of LiPF6 salt.
Introducing dielectric materials is a promising approach to mitigate space‐charge‐layer (SCL) formation, which negatively affects the electrochemical performance of sulfide‐based all‐solid‐state ...batteries (ASSBs). Most previous studies have focused on mitigating SCL formation by introducing dielectric materials, overlooking the fact that significant dielectric properties such as the dipole moment direction and the magnitude of the dielectric constant can influence SCL formation. To clarify the unclear mechanism of dielectric materials mitigating SCL formation, paraelectricity, ferroelectricity, and the magnitude of the dielectric constant are investigated to determine their effect on SCL formation. Paraelectric materials possessing no permanent dipole moment can effectively mitigate the SCL formation better than ferroelectric material with strong permanent dipole moment because of the intrinsic characteristics of the paraelectric material, in which the dipole moment can be aligned along the direction of the electric field applied inside of ASSB. Furthermore, paraelectric materials with a larger dielectric constant have a greater effect in mitigating SCL effect than paraelectric materials with a smaller dielectric constant. Thus, these properties should be considered in cathode‐solid‐electrolyte interface design. This study considers relevant dielectric material characteristics that had not been considered previously, suggesting a new paradigm for optimizing the interfacial resistance of sulfide‐based ASSBs originating from SCL formation.
Paraelectric materials are shown to better alleviate the space‐charge‐layer effect in sulfide‐based all‐solid‐state batteries (ASSBs) compared with ferroelectric materials that possess a strong permanent dipole moment, because of the fact that the dipole moment can be easily aligned along the direction of the electric field applied inside of the sulfide‐based ASSBs.
Numerous previous studies have shown an association between general obesity and hepatocellular carcinoma (HCC). However, relatively few reports on the association of central obesity and HCC are ...available in Asian populations. Therefore, we investigated the association between WC representing central obesity and the risk of HCC in addition to BMI representing general obesity and the risk of HCC in Korea. A total of 10 505 818 participants who received the National Health Insurance Service (NHIS) health checkups in 2009 were screened for study eligibility, and 26 979 cases of HCC occurred during the 7.3 years of mean follow‐up. General obesity increased the risk of HCC with hazard ratios (HRs) of 1.14 (95% CI, 1.11‐1.18) for BMI 25.0‐<30.0 kg/m2 and 1.52 (95% CI, 1.43‐1.61) for BMI ≥30 kg/m2 compared to those whose BMI is within the normal range. Central obesity was also associated with a higher risk of HCC. For the participants with a WC ≥105 cm in men and WC ≥100 cm in women, the risk of HCC was higher than that of the reference group (HR = 1.69, 95% CI, 1.54‐1.85). The HRs were 1.13 (95% CI, 1.07‐1.19) for nonobese participants with central obesity, and 1.34 (95% CI, 1.30‐1.38) for obese participants with central obesity compared to those without both conditions. Our findings suggest that the risk of HCC increases even more when general obesity is combined with central obesity. Moreover, central obesity is associated with the risk of HCC, regardless of general obesity.
What's new?
To date, relatively few reports are available on the association between central obesity and hepatocellular carcinoma (HCC) risk in Asia. In Asian countries, large population‐based National Health Information databases are extremely limited. This large Korean national population‐based cohort study found that general obesity and central obesity are associated with increased risk of HCC. Moreover, central obesity is associated with risk of HCC, regardless of general obesity. The study presents further evidence that obesity contributes to the development of HCC and that clinical measures should be taken to prevent and manage HCC development in obese people.
This study aimed to investigate the prevalence and management of diabetes mellitus, risk-factor control, and comorbidities among Korean adults.
We conducted a cross-sectional analysis of data from ...the Korea National Health and Nutrition Examination Survey to assess the prevalence, treatment, risk factors, comorbidities, and self-management behaviors of diabetes mellitus from 2019 to 2020. We also analyzed data from the Korean National Health Insurance Service to evaluate the use of antidiabetic medications in people with diabetes mellitus from 2002 through 2018.
Among Korean adults aged 30 years or older, the estimated prevalence of diabetes mellitus was 16.7% in 2020. From 2019 through 2020, 65.8% of adults with diabetes mellitus were aware of the disease and treated with antidiabetic medications. The percentage of adults with diabetes mellitus who achieved glycosylated hemoglobin (HbA1c) <6.5% was 24.5% despite the increased use of new antidiabetic medications. We found that adults with diabetes mellitus who achieved all three goals of HbA1c <6.5%, blood pressure (BP) <140/85 mm Hg, and low-density lipoprotein cholesterol <100 mg/dL were 9.7%. The percentage of self-management behaviors was lower in men than women. Excess energy intake was observed in 16.7% of adults with diabetes mellitus.
The prevalence of diabetes mellitus among Korean adults remained high. Only 9.7% of adults with diabetes mellitus achieved all glycemic, BP, and lipid controls from 2019 to 2020. Continuous evaluation of national diabetes statistics and a national effort to increase awareness of diabetes mellitus and improve comprehensive diabetes care are needed.
PurposeDrawing on the theories of social capital and leader–member exchange (LMX), the authors examined the moderated mediation relationships of psychological ownership and perceived supervisory ...support on social capital and organizational knowledge.Design/methodology/approachTo test the proposed model, the authors collected data from 522 employees working in large corporations in South Korea.FindingsThe authors found that (a) social capital was positively related to organizational knowledge sharing, (b) perceived supervisor support mediated the linkage between social capital and knowledge sharing and (c) psychological ownership moderated the indirect effect of social capital on knowledge sharing through perceived supervisor support, such that the indirect effect was stronger for employees with low rather than high psychological ownership.Originality/valueThis study sheds new light on how the nature of relationship between the leader and followers as well as individual's psychological ownership play a crucial role in knowledge sharing.
The three major members of non-coding RNAs (ncRNAs), named microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), play an important role in hepatocellular carcinoma (HCC) ...development. Recently, the competing endogenous RNA (ceRNA) regulation model described lncRNA/circRNA as a sponge for miRNAs to indirectly regulate miRNA downstream target genes. Accumulating evidence has indicated that ceRNA regulatory networks are associated with biological processes in HCC, including cancer cell growth, epithelial to mesenchymal transition (EMT), metastasis, and chemoresistance. In this review, we summarize recent discoveries, which are specific ceRNA regulatory networks (lncRNA/circRNA-miRNA-mRNA) in HCC and discuss their clinical significance.
Abstract Background Context Little is known about the effect of rod stiffness as a risk factor for proximal junctional kyphosis (PJK) after adult spinal deformity (ASD) surgery. Purpose The aim of ...this study was to compare radiographical outcomes after the use of cobalt chrome multiple-rod constructs (CoCr MRC) and titanium alloy two-rod constructs (Ti TRC) for the ASD) surgery with minimum 1-year follow-up. Study Design Retrospective case-control study in two institutes. Patients Sample We included 54 patients who underwent ASD surgery with fusion to sacrum in two academic institutes between 2002 and 2015. Outcome Measures Radiographical outcomes were measured on the standing lateral radiographs before surgery, 1 month postoperatively and at ultimate follow-up. They were composed of pre-and postoperative sagittal vertical axis (SVA), pre-and postoperative lumbar lordosis (LL), pre-and postoperative thoracic kyphosis (TK)+ LL+ pelvic incidence (PI), pre-and postoperative PI minus LL, level of upper instrumented level (UIV), evaluation of fusion after surgery, the presence of proximal junctional kyphosis (PJK), and the occurrence of rod fracture. Methods We reviewed the medical records of 54 patients who underwent ASD surgery. Of these, 20 patients had CoCr MRC and 34 patients had Ti TRC. Baseline data and radiographical measurements were compared between two groups. . The Mann-Whitney U test, the chi square test, and the Fisher exact test were used to compare outcomes between groups. Results Patients of the groups were similar in terms of age, gender, diagnosis, number of three column osteotomy, levels fused, bone mineral density, preoperative TK, pre-and postoperative TK+LL+PI, SVA difference, LL change, pre-and postoperative PI minus LL and the location of UIV (upper-or lower thoracic). However, there were significant differences in the occurrence of PJK and rod breakage (PJK : CoCr MRC: 12 (60%) vs Ti TRC: 9 (26.5%), P =0.015; the occurrence of rod breakage : CoCr MRC: 0 (0%) vs Ti TRC: 11 (32.4%), P =0.004). The time of PJK was less than 12 months after surgery in CoCr MRC group. However, 55.5% (5/9) of PJK developed over 12 months after surgery in Ti TRC group. Conclusions Increasing the rod stiffness by use of CoCr and MRC can prevent rod breakage, however, adversely affects the occurrence and the time of PJK.
To estimate the trends in the prevalence of severe hypoglycemia (SH) in patients with type 2 diabetes in Korea, we investigated the total number of SH episodes among type 2 diabetes patients aged ≥30 ...years who visited the emergency department between 2002 and 2019, using the Korean National Health Insurance Service database. The prevalence of SH events increased from 2002 to 2012; however, it has decreased gradually since 2012. In 2019, the prevalence of SH was 0.6%, with an incidence rate of 4.43 per 1,000 person‐years. Approximately 23,000 SH events occur every year in Korea. Although the incidence is steadily decreasing, there are a considerable number of SH events in type 2 diabetes patients. The decline in the incidence of SH seems to most likely be due to the increased prescription rate of hypoglycemic agents without hypoglycemia risk, less‐strict treatment goals and the individualization of therapy.
The prevalence of severe hypoglycemia in type 2 diabetes patients was 0.29% in 2002 and 0.60% in 2019. The incidence rate for severe hypoglycemia in type 2 diabetes patients was 4.43 per 1,000 people in 2019. Although the prevalence and incidence rate showed decreasing tendencies, the absolute number of patients experiencing severe hypoglycemia in type 2 diabetes has been steadily increasing.
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