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A new design method of an ultra-wideband circularly-polarized planar multiple-input-multiple-output (MIMO) antenna is presented in this paper. The proposed MIMO antenna consists of four unit cell antennas, being comprised of a microstrip feed line and a square slotted ground plane. In the proposed unit cell design, a circular stub is protruded from the ground plane strip for achieving circular polarization. The unit cell of the MIMO antenna is optimized by adjusting design parameters. The compact four-port MIMO antenna prototype is designed on the FR4 substrate with the overall dimensions of 45 × 45 × 1.6 mm3. The proposed four-port MIMO antenna design provides an impedance bandwidth (S11 < −10 dB) of 112% (3.1–11 GHz) and a 3 dB axial ratio bandwidth of 36% (4.8–6.9 GHz). The performance of the fabricated MIMO antenna shows good agreement between the EM simulation and measurement results.
Recent hospital fire incidents in South Korea have heightened the importance of patient evacuation. Moving patients from an intensive care unit (ICU) or emergency department (ED) setting is a challenge due to the complexity of moving acutely unwell patients who are reliant on invasive monitoring and organ support. Despite the importance of patient evacuation, the readiness of ICU and ED for urgent evacuation has not been assessed.
To enhance the readiness and competencies of workers from ICU and ED in the evacuation of patients during a simulated tabletop fire exercise.
A tabletop simulation exercise was developed by the Center for Disaster Relief, Training, and Research referencing the fire evacuation manual developed by the hospital’s ICU and ED. The scenario consisted of evacuating patients horizontally and vertically from each department. The participants’ actions were assessed using a checklist. A debriefing was completed after the exercise to discuss the gaps observed. A post-survey questionnaire was used to evaluate the exercise and assess the perception changes of the participants. All pre-to-post differences within subjects were analyzed with paired t-tests.
A total of 22 and 29 people participated in the exercise from ICU and ED, respectively. Knowledge and confidence improved post-exercise for both ICU and ED scenarios (p<0.05). Course satisfaction was 7.9 and 8.7, respectively for ICU and ED exercise. Correct performance rates for ICU and ED were 59% and 58%, respectively. Common gaps noted for both ICU and ED were wearing protective masks, patient hand-over communication, and preparation for resources.
There need to be exercises to recognize system gaps in place for hospital fire evacuation preparedness. Tabletop simulation exercises are ideal tools for this purpose. Although this was a short 90-minute exercise, this increased familiarity with the evacuation plan, tested the plan, and allowed for identification of gaps.
South Korea experienced Middle East Respiratory Syndrome (MERS) outbreak in 2015. To mitigate the threat posed by MERS, the Ministry of Health and Center for Disease Control designated hospitals to be responsible for managing any suspected or confirmed infectious patient. These hospitals receive mandatory training in managing infectious patients, but many of the trainings lack practical skills practice and pandemic preparedness exercise.
To develop and evaluate a training course designed to train healthcare providers from designated hospitals to enhance their competencies in managing emerging infectious diseases and potential outbreaks.
A two-day course was developed by the Center for Disaster Relief, Training, and Research in collaboration with the Korea Health Promotion Institute using Kern’s 6-step approach. The course consisted of didactic lectures, technical skills training, tabletop simulation, and scenario-based simulation. Table-top simulation exercises consisted of cases involving a single infectious patient detected in the outpatient clinic and outbreak in the emergency department. Scenario-based simulation exercises involved managing a critically ill infectious patient in an isolated ward. A post-survey questionnaire was used to evaluate the course and assess the perception changes of the participants. All pre-to-post differences within subjects were analyzed with paired t-tests.
A total of 121 healthcare providers participated in three separate courses. The competencies for pandemic preparedness knowledge, skills, and attitude improved from pre- to post-course. The differences were all statistically significant (p<0.05). Overall course satisfaction in average for expectation, time, delivery method, and contents were 9.5, 9.2, 9.4, and 9.2, respectively.
There needs to be tests and exercises to recognize gaps of systems in place for pandemic preparedness. Simulation exercises are ideal tools for this purpose. Although this was only a two-day intensive course, this increased familiarity with workflows, tested the coordination of workflows between different disciplines and allowed the identification of gaps.
Spirituality is what gives people meaning and purpose in life, and it has been recognized as a critical factor in patients’ well-being, particularly at the ends of their lives. Studies have demonstrated relationships between spirituality and patient-reported outcomes such as quality of life and mental health. Although a number of studies have suggested that spiritual belief can be associated with mortality, the results are inconsistent. We aimed to determine whether spirituality was related to survival in advanced cancer inpatients in Korea.
For this multicenter study, we recruited adult advanced cancer inpatients who had been admitted to seven palliative care units with estimated survival of <3 months. We measured spirituality at admission using the Korean version of the Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being (FACIT-sp), which comprises two subscales: meaning/peace and faith. We calculated a Kaplan-Meier curve for spirituality, dichotomized at the predefined cutoffs and medians for the total scale and each of the two subscales, and performed univariate regression with a Cox proportional hazard model.
We enrolled a total of 204 adults (mean age: 64.5 ± 13.0; 48.5% female) in the study. The most common primary cancer diagnoses were lung (21.6%), colorectal (18.6%), and liver/biliary tract (13.0%). Median survival was 19.5 days (95% confidence interval [CI95%]: 23.5, 30.6). Total FACIT-sp score was not related to survival time (hazard ratio [HR] = 0.981, CI95% = 0.957, 1.007), and neither were the scores for its two subscales, meaning/peace (HR = 0.969, CI95% = 0.932, 1.008) and faith (HR = 0.981, CI95% = 0.938, 1.026).
Significance of results
Spirituality was not related to survival in advanced cancer inpatients in Korea. Plausible mechanisms merit further investigation.
Family study can provide estimates of overall genetic influences on a particular trait because family relationships provide accurate measures of average genetic sharing. However, evidence of genetic contributions to skin phenotypes is limited, which may preclude genetic studies to identify genetic variants or to understand underlying molecular biology of skin traits. This study aimed to estimate genetic and environmental contributions to selected dermatologic phenotypes, that is, to melanin index, sebum secretion, and skin humidity level in a Korean twin-family cohort. We investigated more than 2,000 individuals from 486 families, including 388 monozygotic twin pairs and 82 dizygotic twin pairs. Variance component method was used to estimate genetic influences in terms of heritability. Heritability of skin melanin index, sebum secretion, and skin humidity (arm and cheek) were estimated to be 0.44 [95% CI 0.38–0.49], 0.21 [95% CI 0.16–0.26], 0.13 [95% CI 0.07–0.18], and 0.11 [95% CI 0.06–0.16] respectively, after adjusting for confounding factors. Our findings suggest that genetics play a major role on skin melanin index, but only mild roles on sebum secretion and humidity. Sebum secretion and skin humidity are controlled predominantly by environmental factors notably on shared environments among family members. We expect that our findings add insight to determinants of common dermatologic traits, and serve as a reference for biologic studies.
To evaluate the appropriateness of the screening strategy for healthcare personnel (HCP) during a hospital-associated Middle East Respiratory Syndrome (MERS) outbreak, we performed a serologic investigation in 189 rRT-PCR–negative HCP exposed and assigned to MERS patients. Although 20%–25% of HCP experienced MERS-like symptoms, none of them showed seroconversion by plaque reduction neutralization test (PRNT).
Devastating disasters around the world directly contribute to significant increases in human mortality and economic costs. The objective of this study was to examine the current state of the Korea Disaster Relief Team that participated in an international training module.
The whole training period was videotaped in order to observe and evaluate the respondents. The survey was carried out after completion of the 3-day training, and the scores were reported by use of a 5-point Likert scale.
A total of 43 respondents were interviewed for the survey, and the results showed that the overall preparedness score for international disasters was 3.4±1.6 (mean±SD). The awareness of the Incident Command System for international disasters was shown to be low (3.5±1.1). Higher scores were given to personnel who took on leadership roles in the team and who answered “I knew my duty” (4.4±0.6) in the survey, as well as to the training participants who answered “I clearly knew my duty” (4.5±0.5).
The preparedness level of the Korea Disaster Relief Team was shown to be insufficient, whereas understanding of the roles of leaders and training participants in the rescue team was found to be high. It is assumed that the preparedness level for disaster relief must be improved through continued training. (Disaster Med Public Health Preparedness. 2016;1–5)
After Super Typhoon Haiyan, a category 5 tropical cyclone, insufficient resources were available for medical management. Many patients in the Philippines were wounded as a result of the disaster. We examined the prevalence, risk factors, and consequences of disaster-related wounds and wound infection in the post-disaster period.
We performed a retrospective review of consecutive patients admitted to a Korean Disaster Relief Team clinic at St. Paul’s Hospital, Tacloban City, Republic of Philippines, between December 9 and 13, 2013. Traumatic injury patients were included; patients not exhibiting a wound were excluded.
Of the 160 patients enrolled in the study, 71 (44.4%) had infected wounds. There were no significant differences in the age, sex, past medical history, wound site, wound depth, injury mechanism, or inducer of injury between the uninfected and infected groups. In the univariate analysis, a foreign-body-contaminated wound, a chronic wound, elapsed time from injury to medical contact, an inadequately cared for wound, and need for subsequent wound management were associated with wound infection (P<0.05). The multivariate analysis revealed that foreign body contamination and having an inadequately cared for wound were associated with wound infection (odds ratio [OR]: 10.12, 95% confidence interval [CI]: 3.59-28.56; OR: 3.51, 95% CI: 1.07-11.51, respectively).
In the post-disaster situation, many wound infections required definitive care. Wound infection was associated with inadequately cared for wounds and foreign-body-contaminated wounds. (Disaster Med Public Health Preparedness. 2016;10:28–33)
To determine the influence of early pain relief for patients with suspected appendicitis on the diagnostic performance of surgical residents.
A prospective randomized, double-blind, placebo-controlled trial was conducted for patients with suspected appendicitis. The patients were randomized to receive placebo (normal saline intravenous [IV]) infusions over 5 minutes or the study drug (morphine 5 mg IV). All of the clinical evaluations by surgical residents were performed 30 minutes after administration of the study drug or placebo. After obtaining the clinical probability of appendicitis, as determined by the surgical residents, abdominal computed tomography was performed. The primary objective was to compare the influence of IV morphine on the ability of surgical residents to diagnose appendicitis.
A total of 213 patients with suspected appendicitis were enrolled. Of these patients, 107 patients received morphine, and 106 patients received placebo saline. The negative appendectomy percentages in each group were similar (3.8% in the placebo group and 3.2% in the pain control group, p=0.62). The perforation rates in each group were also similar (18.9% in the placebo group and 14.3% in the pain control group, p=0.75). Receiver operating characteristic analysis revealed that the overall diagnostic accuracy in each group was similar (the area under the curve of the placebo group and the pain control group was 0.63 v. 0.61, respectively, p=0.81).
Early pain control in patients with suspected appendicitis does not affect the diagnostic performance of surgical residents.
Epidemiological studies have reported that higher education (HE) is associated with a reduced risk of incident Alzheimer's disease (AD). However, after the clinical onset of AD, patients with HE levels show more rapid cognitive decline than patients with lower education (LE) levels. Although education level and cognition have been linked, there have been few longitudinal studies investigating the relationship between education level and cortical decline in patients with AD. The aim of this study was to compare the topography of cortical atrophy longitudinally between AD patients with HE (HE-AD) and AD patients with LE (LE-AD).
We prospectively recruited 36 patients with early-stage AD and 14 normal controls. The patients were classified into two groups according to educational level, 23 HE-AD (>9 years) and 13 LE-AD (≤9 years).
As AD progressed over the 5-year longitudinal follow-ups, the HE-AD showed a significant group-by-time interaction in the right dorsolateral frontal and precuneus, and the left parahippocampal regions compared to the LE-AD.
Our study reveals that the preliminary longitudinal effect of HE accelerates cortical atrophy in AD patients over time, which underlines the importance of education level for predicting prognosis.
This study examined changes in health-related quality of life (HRQoL) and quality of care (QoC) as perceived by terminally ill cancer patients and a stratified set of HRQoL or QoC factors that are most likely to influence survival at the end of life (EoL).
We administered questionnaires to 619 consecutive patients immediately after they were diagnosed with terminal cancer by physicians at 11 university hospitals and at the National Cancer Center in Korea. Subjects were followed up over 161.2 person-years until their deaths. We measured HRQoL using the core 30-item European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, and QoC using the Quality Care Questionnaire–End of Life (QCQ–EoL). We evaluated changes in HRQoL and QoC issues during the first three months after enrollment, performing sensitivity analysis by using data generated via four methods (complete case analysis, available case analysis, the last observation carried forward, and multiple imputation).
Emotional and cognitive functioning decreased significantly over time, while dyspnea, constipation, and pain increased significantly. Dignity-conserving care, care by healthcare professionals, family relationships, and QCQ–EoL total score decreased significantly. Global QoL, appetite loss, and Eastern Cooperative Oncology Group Performance Status (ECOG–PS) scores were significantly associated with survival.
Significance of results:
Future standardization of palliative care should be focused on assessment of these deteriorated types of quality. Accurate estimates of the length of life remaining for terminally ill cancer patients by such EoL-enhancing factors as global QoL, appetite loss, and ECOG–PS are needed to help patients experience a dignified and comfortable death.
Cancer is a leading cause of death, and the dietary pattern in Korea is changing rapidly from a traditional Korean diet to a Westernised diet. In the present study, we investigated the effects of dietary factors on cancer risk with a prospective cohort study. Among 26 815 individuals who participated in cancer screening examinations from September 2004 to December 2008, 8024 subjects who completed a self-administered questionnaire concerning demographic and lifestyle factors, and a 3 d food record were selected. As of September 2013, 387 cancer cases were identified from the National Cancer Registry System, and the remaining individuals were included in the control group. The hazard ratio (HR) of cancer for the subjects older than or equal to 50 years of age was higher (HR 1·80, 95 % CI 1·41, 2·31; P< 0·0001) than that for the other subjects. Red meat consumption, Na intake and obesity (BMI ≥ 25 kg/m2) were positively associated with overall cancer incidence in men (HR 1·41, 95 % CI 1·02, 1·94; P= 0·0382), gastric cancer (HR 2·34, 95 % CI 1·06, 5·19; P= 0·0365) and thyroid cancer (HR 1·56, 95 % CI 1·05, 2·31; P= 0·0270), respectively. Participants who had at least three dietary risk factors among the high intakes of red meat and Na, low intakes of vegetables and fruits, and obesity suggested by the World Cancer Research Fund/American Institute for Cancer Research at baseline tended to have a higher risk of cancer than the others (HR 1·26, 95 % CI 0·99, 1·60; P= 0·0653). In summary, high intakes of red meat and Na were significant risk factors of cancer among Koreans.
To investigate whether low vitamin D status was related to insulin resistance (IR) or impaired fasting glucose (IFG) in Korean adolescents, after adjusting for total body fat mass (FM).
A cross-sectional study.
Korea National Health and Nutrition Examination Survey (KNAHNES) 2009–2010.
In total, 1466 participants (769 males) aged 10–19 years were assessed for serum 25-hydroxyvitamin D (25(OH)D) levels, for FM by whole-body dual-energy X-ray absorptiometry and for IR by homeostasis model assessment (HOMA-IR) after an 8 h fast.
Age-, sex-, season- and physical-activity-adjusted regression models showed that serum 25(OH)D levels were significantly related to markers of adiposity (P = 0·016 for FM (g), P = 0·023 for FM (%) and P = 0·035 for fat mass index). When the participants were stratified into three 25(OH)D categories (<37·5 nmol/l (n 553), 37·5 to < 50 nmol/l (n 543) and ≥ 50 nmol/l (n 370)), significantly decreasing trends were observed for fasting insulin (all P < 0·001), HOMA-IR (all P < 0·001) and the odds ratios for IFG (all P for trend < 0·05) from the lowest to the highest 25(OH)D category, after adjustments for age, sex, physical activity and all markers of adiposity. In the multivariate logistic regression analysis, the likelihood of participants in the lowest serum 25(OH)D category having IFG was 2·96–3·15 compared with those in the highest 25(OH)D category (all P < 0·05).
There was a significant inverse relationship between vitamin D status and IR and the risk of IFG, independent of adiposity, in Korean adolescents.
By chemical vapor deposition, aligned single wall carbon nanotubes (SWNTs) and a network of SWNTs are simultaneously grown as the channel and the source–drain electrodes of thin film transistors (TFTs). The increase of aligned SWNTs increases the channel conductance without changing the contact resistance. However, the increase of network-type SWNTs from 19 to 32.5 (SWNTs/μm) decreases the contact resistance fivefold. The contact resistance of all-SWNT TFT is three times lower compared with that of an SWNT TFT using metal electrodes. The all-SWNT TFTs transferred on polyethylene terephthalate (PET) show a transparency of >80% in the visible range of wavelengths.
Thiazolidinediones, such as rosiglitazone or pioglitazone, are anti-diabetic agents that have been expected to show a beneficial effect in Alzheimer's disease (AD) because of their anti-inflammatory effect. However, these agents have failed to show a significant beneficial effect on AD in recent clinical trials. Here, we suggest that low-dose rosiglitazone treatment, and not the conventional doses, has an amyloid β (Aβ)-clearing effect by increasing LRP1, an Aβ outward transporter in the blood–brain barrier. Rosiglitazone up-regulated LRP1 mRNA and protein expression and LRP1 promoter activity in human brain microvascular endothelial cells (HBMECs). Aβ uptake through LRP1 in HBMECs was also increased by rosiglitazone. This increase in LRP1 and Aβ uptake was observed in up to 10 nm rosiglitazone concentration. At concentrations above 20 nm rosiglitazone, the LRP1 expression and Aβ uptake in HBMECs were not altered. The possible mechanism of this unusual dose response is discussed. This study suggests a new therapeutic application of thiazolidinediones for AD at a much lower dose than the doses used for diabetes treatment.
We investigated the pressure dependence of the inductive coupled plasma (ICP) oxidation on the electrical characteristics of the thin oxide films. Activation energies and electron temperatures with different pressures were estimated. To demonstrate the pressure effect on the plasma oxide quality, simple N type metal-oxide-semiconductor (NMOS) transistors were fabricated and investigated in a few electrical properties. At higher pressure than 200mTorr, plasma oxide has a slightly higher on-current and a lower interfacial trap density. The on-current gain seems to be related to the field mobility increase and the lower defective interface to the electron temperature during oxidation.
Non-alcoholic fatty liver disease (NAFLD) has been deeply associated with visceral adiposity, adipose tissue inflammation and a variety of adipocytokines. We reported previously that genistein inhibited NAFLD by enhancing fatty acid catabolism. However, this molecular approach focused on hepatic metabolism. Thus, we have attempted to determine whether this anti-steatotic effect of genistein is linked to visceral adipocyte metabolism. C57BL/6J mice were fed on normal-fat (NF) diet, high-fat (HF) diet and HF diet supplemented with genistein (1, 2 and 4 g/kg diet) for 12 weeks. Mice fed on the HF diet gained body weight, exhibited increased visceral fat mass and elevated levels of serum and liver lipids, and developed NAFLD, unlike what was observed in mice fed on the NF diet. However, genistein supplementation (2 and 4 g/kg diet) normalised these alternations. In the linear regression analysis, visceral fat (R 0·77) and TNFα (R 0·62) were strongly correlated with NAFLD among other NAFLD-related parameters. Genistein supplementation suppressed the hypertrophy of adipocytes via the up-regulation of genes involved in fatty acid β-oxidation, including PPARα, 5′-AMP-activated protein kinase and very long-chain acyl CoA dehydrogenase, as well as through the down-regulation of genes associated with adipogenesis or lipogenesis, including liver X receptor-α, sterol-regulatory element-binding protein-1c, PPARγ, retinoid X receptor-α and acetyl CoA carboxylase 2. Moreover, genistein supplementation augmented an anti-steatohepatitic adiponectin TNF and reduced a steatohepatitic TNFα. Collectively, these findings show that genistein may prevent NAFLD via the regulation of visceral adipocyte metabolism and adipocytokines.
Brain-derived neurotrophic factor (BDNF) signalling via tyrosine kinase B receptors may play an important role in ovarian development and function. It has been reported that metformin elevates the activity of Tyrosine kinase receptors and may amplify BDNF signalling. The objective of this study was to investigate the effect of BDNF during in vitro maturation (IVM) and/or in vitro culture (IVC) (Experiment 1), and to evaluate the collaborative effect of BDNF and metformin treatment on the developmental competence of bovine in vitro fertilized (IVF) embryos (Experiment 2). In Experiment 1, BDNF, which was added to our previously established IVM systems, significantly increased the proportions of MII oocytes at both 10 ng/ml (86.7%) and 100 ng/ml (85.4%) compared with the control (64.0%). However, there was no statistically significant difference in blastocyst development between the control or BDNF-supplemented groups. In Experiment 2, in order to investigate the effect of BDNF (10 ng/ml) and/or metformin (10−5 M) per se, TCM-199 without serum and hormones was used as the control IVM medium. The BDNF (48.3%) and BDNF plus metformin (56.5%) significantly enhanced the proportions of MII oocytes compared with the control (34.4%). Although, BDNF or metformin alone had no effect in embryo development, BDNF plus metformin significantly improved early embryo development to the 8–16-cell stage compared with the control (16.5 vs. 5.5%). In conclusion, the combination of BDNF and metformin may have a collaborative effect during the IVM period. These results could further contribute to the establishment of a more efficient bovine in vitro embryo production system.
As potential substitutes for traditional Ti(Zr)–Cu–Ni-based brazing metals for high strength Ti alloys as well as a study for metallic glass, Zr–Ti–Ni-based alloys have been attracting much attention recently. In this study, the melting temperatures and microstructures of the Zr(Ti)-rich Zr–Ti–Ni alloys with Ni content below 33.3 at.% were systematically studied. A ternary deep eutectic alloy consisting of three phases was found at the composition of Zr50Ti26Ni24 with a solidus temperature of 798 °C and a liquidus temperature of 809 °C, which are significantly lower than the Zr2Ni–(Zr,Ti)2Ni pseudobinary eutectic melting temperature of 850 °C. This ternary eutectic reaction can be presented as L → α-(Zr/Ti) solid solution + Zr2Ni + ternary Laves (Zr,Ti)2Ni.