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1.
Polymers (Basel) ; 16(7)2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38611134

ABSTRACT

Vulcanization is a chemical modification of rubber that requires a considerable amount of thermal energy. To save thermal energy, the kinetics of rubber vulcanization should be improved. In this article, the curing properties of rubber vulcanization are thoroughly investigated using the moving die rheometer (MDR) technique. To enhance the kinetics in different stages of ZnO-based sulfur vulcanization systems, small amounts of MgO were added. The results revealed that the small amount of 1 to 2 phr (per hundred grams of rubber) of MgO in the controlled 5 phr ZnO-based curing systems can significantly improve the curing kinetics. For example, the optimum curing time of 1 phr MgO added to the 5 phr ZnO-containing semi-efficient vulcanization system at different temperatures was more than half that of the controlled 5 phr ZnO-only compound. While maintaining a similar rate of vulcanization, the vulcanization temperature can be reduced by up to 20 °C by using MgO as a co-cure activator, which exhibits similar or better rheometric mechanical properties compared to the controlled compounds. With the addition of MgO as a co-cure activator, the vulcanization reactions become very fast, enabling vulcanization to be completed, even at the boiling point of water (100 °C) with an affordable curing time (<1 h). By reducing the vulcanization temperature, the scorch safety time can be enhanced in the ZnO/MgO-based binary cure activator-containing vulcanizates. Overall, MgO could be a potential candidate as a co-cure activator with ZnO for the vulcanization of rubber, offering better economical and eco-friendly methods.

2.
Sci Rep ; 14(1): 8164, 2024 04 08.
Article in English | MEDLINE | ID: mdl-38589377

ABSTRACT

Schistosoma japonicum is endemic in the Philippines. The Kato-Katz (KK) method was used to diagnose S. japonicum. This is impractical, particularly when the sample size is limited. Knowledge on point-of-care circulating cathodic antigen (CCA) test performance for S. japonicum is limited. Determining the sensitivity and specificity of new diagnostics is difficult when the gold standard test is less effective or absent. Latent class analysis (LCA) can address some limitations. A total of 484 children and 572 adults from the Philippines were screened for S. japonicum. We performed Bayesian LCA to estimate the infection prevalence, sensitivity and specificity of each test by stratifying them into two age groups. Observed prevalence assessed by KK was 50.2% and 31.8%, and by CCA was 89.9% and 66.8%, respectively. Using Bayesian LCA, among children, the sensitivity and specificity of CCA were 94.8% (88.7-99.4) and 21.5% (10.5-36.1) while those of KK were 66.0% (54.2-83.3) and 78.1% (61.1-91.3). Among adults, the sensitivity and specificity of CCA were 86.4% (76.6-96.9) and 62.8% (49.1-81.1) while those of KK were 43.6% (35.1-53.9) and 85.5% (75.8-94.6). Overall, CCA was more sensitive than KK, regardless of the age group at diagnosis, as KK was more specific. KK and CCA have different diagnostic performance, which should inform their use in the planning and implementation of S. japonicum control programs.


Subject(s)
Schistosoma japonicum , Schistosomiasis mansoni , Child , Adult , Animals , Humans , Schistosoma mansoni , Antigens, Helminth , Bayes Theorem , Latent Class Analysis , Point-of-Care Systems , Feces/chemistry , Sensitivity and Specificity , Prevalence
3.
Coron Artery Dis ; 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38682470

ABSTRACT

BACKGROUND: The average glycated hemoglobin (HbA1c) may not accurately reflect glycemic control status during the mid-term after acute myocardial infarction (AMI). We aimed to evaluate changes in HbA1c and their effect on mid-term clinical outcomes in patients with diabetes and AMI. METHODS: We enrolled patients with diabetes (n = 967) who underwent HbA1c measurement in the Korean nationwide registry. These patients were categorized into three groups based on changes in HbA1c from index admission to the 1-year follow-up visit: a decrease in HbA1c > 1%, changes in HbA1c within 1%, and an increase in HbA1c > 1%. Clinical outcomes at 24 months were examined. RESULTS: The baseline HbA1c levels were 8.55 ±â€…0.85, 7.00 ±â€…0.98 and 7.07 ±â€…1.05 (P = 0.001) and HbA1c levels after 1 year were 6.62 ±â€…0.73, 7.05 ±â€…0.98 and 9.26 ±â€…1.59 (P = 0.001) for patients with 3 groups, respectively. Patients with a 1% decrease in HbA1c had significantly lower incidence of major adverse cardiovascular events (MACE), cardiac death, and rehospitalization after 24 months than those with a 1% increase in HbA1c. However, in the Cox regression analysis, a >1% decrease in HbA1c change was not an independent factor for MACE, cardiac death, and rehospitalization. CONCLUSIONS: Our analysis indicates that an HbA1c decrease of >1% within the first 12 months was not an independent prognostic factor until the 24-month mark. Therefore, standard diabetic control is recommended for patients with diabetes and AMI for up to 2 years.

4.
Vaccine ; 42(14): 3333-3336, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38604914

ABSTRACT

BACKGROUND: Vaccines are vital for public health, but concerns about adverse effects, particularly myocarditis and pericarditis linked to COVID-19 vaccines-, persist. This study investigates the application of Brighton Collaboration case definition to national vaccine safety data related to post-COVID-19 vaccine myo/pericarditis, utilizing claims under the Korea National Vaccine Injury Compensation Program (NIVCP). METHODS: This study analyzed 190 medical records of individuals who claimed to have developed myo/pericarditis after receiving the COVID-19 vaccine, as reported to the NVICP between specified dates, categorizing cases based on the Brighton criteria for myocarditis or pericarditis. RESULTS: Between 2021-2022, NVICP received 190 cases meeting the Brighton criteria for myocarditis or pericarditis at levels 1, 2, or 3. Most cases fell into Level 2 (70%), followed by Level 1 (29%), and one at Level 3 (1%), with Level 1 cases showing a higher hospitalization rate (87.3%) and a notable proportion requiring admission to the Intensive Care Unit (25.5%). Chest pain and Troponin-I/T elevation were common findings in Level 1 cases, while Level 2 cases exhibited similar patterns but at a slightly lower frequency. Electrocardiogram and echocardiography findings differed between the two levels. CONCLUSION: The Brighton Collaboration case definition proved valuable for classifying and assessing AEFI data, enhancing our understanding of the potential relationship between myocarditis and the COVID-19 vaccine.


Subject(s)
COVID-19 Vaccines , COVID-19 , Myocarditis , Pericarditis , Humans , Myocarditis/etiology , Pericarditis/etiology , Republic of Korea , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/administration & dosage , Male , Adolescent , Female , COVID-19/prevention & control , COVID-19/epidemiology , Hospitalization/statistics & numerical data , SARS-CoV-2/immunology
5.
Korean Circ J ; 54(5): 256-267, 2024 May.
Article in English | MEDLINE | ID: mdl-38654455

ABSTRACT

BACKGROUND AND OBJECTIVES: Accumulating evidence shows that sodium-glucose cotransporter 2 inhibitors (SGLT2is) reduce adverse cardiovascular outcomes. However, whether SGLT2i, compared with other antidiabetic drugs, reduce the new development of atrial fibrillation (AF) is unclear. In this study, we compared SGLT2i with dipeptidyl peptidase-4 inhibitors (DPP-4is) in terms of reduction in the risk of AF in individuals with type 2 diabetes. METHODS: We included 42,786 propensity score-matched pairs of SGLT2i and DPP-4i users without previous AF diagnosis using the Korean National Health Insurance Service database between May 1, 2016, and December 31, 2018. RESULTS: During a median follow-up of 1.3 years, SGLT2i users had a lower incidence of AF than DPP-4i users (1.95 vs. 2.65 per 1,000 person-years; hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.55-0.97; p=0.028]). In individuals without heart failure, SGLT2i users was associated with a decreased risk of AF incidence (HR, 0.70; 95% CI, 0.52-0.94; p=0.019) compared to DPP-4i users. However, individuals with heart failure, SGLT2i users was not significantly associated with a change in risk (HR, 1.04; 95% CI, 0.44-2.44; p=0.936). CONCLUSIONS: In this nationwide cohort study of individuals with type 2 diabetes, treatment with SGLT2i was associated with a lower risk of AF compared with treatment with DPP-4i.

6.
Prev Vet Med ; 225: 106157, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38452603

ABSTRACT

Coxiella burnetii is a Gram-negative bacterium that causes the zoonotic disease Q fever. Wild boars serve as reservoirs for C. burnetii. This study aimed to identify the risk factors associated with C. burnetii infection in wild boars. We analyzed the data from 975 wild boar samples collected from June to November 2021 in South Korea. We utilized the indirect ELISA to detect antibodies against C. burnetii. A sample optical density to positive-control optical density value exceeding 50% was classified as positive. We gathered data on the forestation, terrain, weather, agriculture, and animal density of the region where the samples were collected. Continuous variables were categorized into tertiles. We performed a univariate logistic regression analysis and included variables with a p-value < 0.2 in the final multivariable logistic regression model. In our multivariable logistic regression analysis to identify risk factors for C. burnetii infection in wild boars, we used a forward selection method to enter variables based on the order of their significance. We performed the final multivariable logistic regression analyses using either continuous variables or variables categorized into tertiles. The prevalence of C. burnetii was 14.6% (n=142). Locations with the highest maximum wind speeds (3.92-8.24 m/s) showed a 59% increase in infection odds compared to locations with the lowest speeds (1.45-3.25 m/s)(p=0.044). For each 1 m/s increase in maximum wind speed, infection odds increased by 24.1% (p=0.037). Regions with the highest percentage of paddy fields per area (8.3-45%) showed a 76% increase in infection odds compared to regions with the lowest percentage (0-1.5%)(p=0.011). For each 1% increase in the proportion of paddy fields per area, infection odds increased by 3.3% (p=0.003). High maximum wind speed and a high percentage of paddy field were identified as significant risk factors for C. burnetii infection in wild boars.


Subject(s)
Coxiella burnetii , Q Fever , Animals , Seroepidemiologic Studies , Q Fever/epidemiology , Q Fever/veterinary , Q Fever/microbiology , Risk Factors , Republic of Korea/epidemiology , Prevalence
7.
Gels ; 10(1)2024 Jan 21.
Article in English | MEDLINE | ID: mdl-38275854

ABSTRACT

"Gel-type" soft and stretchable magneto-mechanical composites made of silicone rubber and iron particles are in focus because of their high magnetic sensitivity, and intelligence perspective. The "intelligence" mentioned here is related to the "smartness" of these magneto-rheological elastomers (MREs) to tune the "mechanical stiffness" and "output voltage" in energy-harvesting applications by switching magnetic fields. Hence, this work develops "gel-type" soft composites based on rubber reinforced with iron particles in a hybrid with piezoelectric fillers such as barium titanate. A further aspect of the work relies on studying the mechanical stability of intelligence and the stretchability of the composites. For example, the stretchability was 105% (control), and higher for 158% (60 per 100 parts of rubber (phr) of barium titanate, BaTiO3), 149% (60 phr of electrolyte iron particles, EIP), and 148% (60 phr of BaTiO3 + EIP hybrid). Then, the magneto-mechanical aspect will be investigated to explore the magnetic sensitivity of these "gel-type" soft composites with a change in mechanical stiffness under a magnetic field. For example, the anisotropic effect was 14.3% (60 phr of EIP), and 4.4% (60 phr of hybrid). Finally, energy harvesting was performed. For example, the isotropic samples exhibit ~20 mV (60 phr of BaTiO3), ~5.4 mV (60 phr of EIP), and ~3.7 mV (60 phr of hybrid). However, the anisotropic samples exhibit ~5.6 mV (60 phr of EIP), and ~8.8 mV (60 phr of hybrid). In the end, the composites prepared have three configurations, namely one with electro-mechanical aspects, another with magnetic sensitivity, and a third with both features. Overall, the experimental outcomes will make fabricated composites useful for different intelligent and stretchable applications.

8.
Vet Med Sci ; 10(1): e1334, 2024 01.
Article in English | MEDLINE | ID: mdl-38100149

ABSTRACT

OBJECTIVE: The tear clearance rate (TCR), determined using anterior segment optical coherence tomography (AS-OCT) images, and its correlation with ocular surface parameters, including blink rate, Schirmer tear test-1 (STT-1) and tear film breakup time (TFBUT), were evaluated. ANIMALS STUDIED: Left eyes of 20 client-owned dogs with no ocular disease symptoms. PROCEDURES: The tear meniscus height (TMH) was evaluated using AS-OCT images before the instillation of 5 µL saline (TMHbase ), immediately post-instillation (TMH0 ), 30-s post-instillation (TMH0.5 ) and at 1 min intervals for 5 min post-instillation (TMH1 , TMH2 , TMH3 , TMH4 and TMH5 ). The TCR was calculated using the formula [(TMH0  - TMH0.5 )/TMH0 ]×100 (%). The eyes were classified into two groups with the median: 'High TMHbase ' (n = 10) and 'Low TMHbase ' (n = 10). Eyes with STT-1 values ≥15 mm/min and TFBUT ≥ 12 s were assigned to the 'Satisfied' subgroup, whereas eyes not satisfying these criteria were assigned to the 'Not satisfied' subgroup. RESULTS: TMH0 was higher than TMH0.5 (p = 0.02), wherein TMH0.5 to TMH5 did not differ significantly. The TCR and blink rate were negatively correlated (p = 0.02). The 'Not satisfied' subgroup in the low TMHbase group had a lower TCR (p = 0.02) and higher blink rate (p = 0.04) than the 'Satisfied' subgroup. CONCLUSIONS: TCR can be evaluated using AS-OCT in dogs. Eyes with a lower TCR blink more frequently. TMH merits studying to understand ocular surface health.


Subject(s)
Dog Diseases , Dry Eye Syndromes , Humans , Dogs , Animals , Tomography, Optical Coherence/veterinary , Tomography, Optical Coherence/methods , Dry Eye Syndromes/diagnosis , Dry Eye Syndromes/veterinary , Tears , Receptors, Antigen, T-Cell
9.
Medicine (Baltimore) ; 102(50): e36627, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38115307

ABSTRACT

RATIONALE: The ring finger protein 213 (RNF213) p.R4810K variant has been identified as being associated with Moyamoya disease (MMD), a condition that is more prevalent in East Asians. This association extends beyond cerebral vessels and has been implicated in coronary artery disease. PATIENT CONCERNS: A 36-year-old female was admitted to the emergency room with chest pain. Although the patient had no known underlying conditions or risk factors for atherosclerosis, she was diagnosed with unstable angina and underwent percutaneous coronary intervention. Given her older sister's ongoing treatment for MMD, it was suspected that the patient's coronary artery disease might be linked to the MMD-associated gene mutation. DIAGNOSES: Coronary angiography revealed 80% narrowing of the proximal left anterior descending artery. Based on clinical symptoms and coronary angiography, we diagnosed it as unstable angina. INTERVENTION: Due to the family history of MMD and detection of the RNF213 p.R4810K heterozygous variant in the patient's older sister, genetic counseling was recommended. Next-generation sequencing for vascular diseases was performed. OUTCOMES: Genetic testing confirmed the presence of an RNF213 p.R4810K heterozygous variant in the patient, mirroring that in her sister. An RNF213 p.C4397R heterozygous variant was identified concomitantly, although it was categorized as a variant of uncertain significance. Coronary artery disease has been attributed to the RNF213 p.R4810K variant. LESSONS: Although MMD is rare in Western populations, it is more common in East Asian populations. Traditionally, MMD diagnoses have focused solely on the cerebral vessels without guidelines for the assessment of other vascular involvements. This familial case underscores the fact that a single genetic mutation can manifest in diverse ways in different diseases. Hence, the need and regularity of systemic vessel screening should be thoughtfully considered in such a context.


Subject(s)
Coronary Artery Disease , Moyamoya Disease , Humans , Female , Adult , Genetic Predisposition to Disease , Coronary Artery Disease/diagnosis , Coronary Artery Disease/genetics , Moyamoya Disease/diagnosis , Angina, Unstable , Adenosine Triphosphatases , Ubiquitin-Protein Ligases/genetics
10.
Polymers (Basel) ; 15(17)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37688238

ABSTRACT

Mechanical robustness and high energy efficiency of composite materials are immensely important in modern stretchable, self-powered electronic devices. However, the availability of these materials and their toxicities are challenging factors. This paper presents the mechanical and energy-harvesting performances of low-cost natural rubber composites made of stearic acid-modified diatomaceous earth (mDE) and carbon nanotubes (CNTs). The obtained mechanical properties were significantly better than those of unfilled rubber. Compared to pristine diatomaceous earth, mDE has higher reinforcing efficiencies in terms of mechanical properties because of the effective chemical surface modification by stearic acid and enhanced filler-rubber interactions. The addition of a small amount of CNT as a component in the hybrid filler systems not only improves the mechanical properties but also improves the electrical properties of the rubber composites and has electromechanical sensitivity. For example, the fracture toughness of unfilled rubber (9.74 MJ/m3) can be enhanced by approximately 484% in a composite (56.86 MJ/m3) with 40 phr (per hundred grams of rubber) hybrid filler, whereas the composite showed electrical conductivity. At a similar mechanical load, the energy-harvesting efficiency of the composite containing 57 phr mDE and 3 phr CNT hybrid filler was nearly double that of the only 3 phr CNT-containing composite. The higher energy-harvesting efficiency of the mDE-filled conductive composites may be due to their increased dielectric behaviour. Because of their bio-based materials, rubber composites made by mDE can be considered eco-friendly composites for mechanical and energy harvesting applications and suitable electronic health monitoring devices.

11.
Gels ; 9(9)2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37754367

ABSTRACT

Electro-mechanical configurations can be piezo-electric transducers, triboelectric generators, electromagnetic induction, or hybrid systems. Our present study aims at developing energy generation through the piezoelectric principle. Gel-type soft SR with Shore A hardness below 30 was used as a versatile material for an elastomeric substrate. Also, multi-wall carbon nanotube (MWCNT), and diatomaceous earth (DE) were used as reinforcing fillers. This "gel-type" soft SR has crosslinking polymer networks with silicone encapsulated within its structure. Mechanical properties such as modulus or stretchability are of utmost importance for such devices based on "gel-type" soft. From the experiments, some of the mechanical aspect's values are summarized. For example, the stretchability was 99% (control) and changes to 127% (3 phr, MWCNT), 76% (20 phr DE), and 103% (20 phr hybrid). From electro-mechanical tests, the output voltage was 0.21 mV (control) and changed to 0.26 mV (3 phr, MWCNT), 0.19 mV (20 phr DE), and 0.29 mV (20 phr hybrid). Moreover, from real-time biomechanical human motion tests in "gel-type" soft-based composites, a relationship among output voltage from machine to human motions was established. Overall, these configurations make them promising against traditional portable devices such as batteries for small power applications such as mobile phones.

12.
Clin Psychopharmacol Neurosci ; 21(3): 583-593, 2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37424425

ABSTRACT

Objective: Maumgyeol Basic service is a mental health evaluation and grade scoring software using the 2 channels EEG and photoplethysmogram (PPG). This service is supposed to assess potential at-risk groups with mental illness more easily, rapidly, and reliably. This study aimed to evaluate the clinical implication of the Maumgyeol Basic service. Methods: One hundred one healthy controls and 103 patients with a psychiatric disorder were recruited. Psychological evaluation (Mental Health Screening for Depressive Disorders [MHS-D], Mental Health Screening for Anxiety Disorders [MHS-A], cognitive stress response scale [CSRS], 12-item General Health Questionnaire [GHQ-12], Clinical Global Impression [CGI]) and digit symbol substitution test (DSST) were applied to all participants. Maumgyeol brain health score and Maumgyeol mind health score were calculated from 2 channel frontal EEG and PPG, respectively. Results: Participants were divided into three groups: Maumgyeol Risky, Maumgyeol Good, and Maumgyeol Usual. The Maumgyeol mind health scores, but not brain health scores, were significantly lower in the patients group compared to healthy controls. Maumgyeol Risky group showed significantly lower psychological and cognitive ability evaluation scores than Maumgyeol Usual and Good groups. Maumgyel brain health score showed significant correlations with CSRS and DSST. Maumgyeol mind health score showed significant correlations with CGI and DSST. About 20.6% of individuals were classified as the No Insight group, who had mental health problems but were unaware of their illnesses. Conclusion: This study suggests that the Maumgyeol Basic service can provide important clinical information about mental health and be used as a meaningful digital mental healthcare monitoring solution to prevent symptom aggravation.

13.
Front Cardiovasc Med ; 10: 1215389, 2023.
Article in English | MEDLINE | ID: mdl-37492160

ABSTRACT

Background: Primary cardiac tumors are rare, and malignant primary cardiac tumors are even rarer. Cardiac osteosarcoma is a very rare type of malignant primary cardiac tumor with limited reported cases. We present a case report of cardiac osteosarcoma and review its characteristics and the related literature. Case summary: A 44-year-old female patient without a specific medical history presented with intermittent dyspnea that started 1 month prior to presentation. A heterogeneous mass was observed in the left atrium on echocardiography and a large mass was observed in the left atrium on computed tomography. Surgery was performed under the suspicion of atypical cardiac myxoma, and the tumor was successfully removed. However, postoperative histopathological examination revealed cardiac osteosarcoma. The patient underwent chemotherapy and has been well maintained without recurrence for 10 years. Conclusion: We present a case report of the echocardiographic features and treatment strategies for cardiac osteosarcoma, an extremely rare cardiac tumor. Multimodal imaging can be helpful; however, a histological diagnosis through surgical resection is essential. Appropriate treatment and follow-up based on histological findings are necessary.

14.
Polymers (Basel) ; 15(10)2023 May 12.
Article in English | MEDLINE | ID: mdl-37242867

ABSTRACT

The demand for multi-functional elastomers is increasing, as they offer a range of desirable properties such as reinforcement, mechanical stretchability, magnetic sensitivity, strain sensing, and energy harvesting capabilities. The excellent durability of these composites is the key factor behind their promising multi-functionality. In this study, various composites based on multi-wall carbon nanotubes (MWCNT), clay minerals (MT-Clay), electrolyte iron particles (EIP), and their hybrids were used to fabricate these devices using silicone rubber as the elastomeric matrix. The mechanical performance of these composites was evaluated, with their compressive moduli, which was found to be 1.73 MPa for the control sample, 3.9 MPa for MWCNT composites at 3 per hundred parts of rubber (phr), 2.2 MPa for MT-Clay composites (8 phr), 3.2 MPa for EIP composites (80 phr), and 4.1 MPa for hybrid composites (80 phr). After evaluating the mechanical performance, the composites were assessed for industrial use based on their improved properties. The deviation from their experimental performance was studied using various theoretical models such as the Guth-Gold Smallwood model and the Halpin-Tsai model. Finally, a piezo-electric energy harvesting device was fabricated using the aforementioned composites, and their output voltages were measured. The MWCNT composites showed the highest output voltage of approximately 2 milli-volt (mV), indicating their potential for this application. Lastly, magnetic sensitivity and stress relaxation tests were performed on the hybrid and EIP composites, with the hybrid composite demonstrating better magnetic sensitivity and stress relaxation. Overall, this study provides guidance on achieving promising mechanical properties in such materials and their suitability for various applications, such as energy harvesting and magnetic sensitivity.

15.
Polymers (Basel) ; 15(9)2023 May 05.
Article in English | MEDLINE | ID: mdl-37177335

ABSTRACT

Recently, hybrid fillers have been found to be more advantageous in energy-harvesting composites. This study investigated the mechanical and electromechanical performances of silicone rubber-based composites made from hybrid fillers containing conductive nanocarbon black (NCB) and molybdenum disulfide (MoS2). A hybrid filler system containing only 3 phr (per hundred grams of rubber) MoS2 and 17 phr NCB provided higher fracture strain, better tensile strength, and excellent toughness values compared to the 20 phr NCB-only-filled and 5 phr MoS2-only-filled rubber composites. The chemical cross-link densities suggest that NCB promoted the formation of cross-links, whereas MoS2 slightly reduced the cross-link density. The higher mechanical properties in the hybrid filler systems suggest that the filler particles were more uniformly distributed, which was confirmed by the scanning electron microscope study. Uniformly distributed filler particles with moderate cross-link density in hybrid filler systems greatly improved the fracture strain and fracture toughness. For example, the hybrid filler with a 17:3 ratio of NCB to MoS2 showed a 184% increment in fracture toughness, and a 93% increment in fracture strain, compared to the 20 phr NCB-only-filled composite. Regarding electromechanical sensing with 2 kPa of applied cyclic pressure, the hybrid filler (17:3 CB to MoS2) performed significantly better (~100%) than the 20 phr NCB-only compound. This may have been due to the excellent distribution of conducting NCB networks and piezoelectric MoS2 that caused symmetric charging-discharging in the toughened hybrid composite. Thus, hybrid composites with excellent fatigue resistance can find dynamic applications, such as in blood pressure measurement.

16.
Clin Psychopharmacol Neurosci ; 21(2): 359-369, 2023 May 30.
Article in English | MEDLINE | ID: mdl-37119228

ABSTRACT

Objective: Posttraumatic stress disorder (PTSD) is characterized by increased inflammatory processing and altered brain volume. In this study, we investigated the relationship between inflammatory markers and brain volume in patients with PTSD. Methods: Forty-five patients with PTSD, and 70 healthy controls (HC) completed clinical assessments and self-reported psychopathology scales. Factors associated with inflammatory responses including brain-derived neurotrophic factor and four inflammatory biomarkers (C-reactive protein, cortisol, Interleukin-6, and homocysteine) and T1-magnetic resonance imaging of the brain were measured. Results: In the PTSD group, cortisol level was significantly lower (t = 2.438, p = 0.046) than that of the HC. Cortisol level was significantly negatively correlated with the left thalamus proper (r = -0.369, p = 0.035), right thalamus proper (r = -0.394, p = 0.014), right frontal pole (r = -0.348, p = 0.039), left occipital pole (r = -0.338, p = 0.044), and right superior occipital gyrus (r = -0.397, p = 0.008) in patients with PTSD. However, these significant correlations were not observed in HC. Conclusion: Our results indicate that increased cortisol level, even though its average level was lower than that of HC, is associated with smaller volumes of the thalamus, right frontal pole, left occipital pole, and right superior occipital gyrus in patients with PTSD. Cortisol, a major stress hormone, might be a reliable biomarker to brain volumes and pathophysiological pathways in patients with PTSD.

17.
Int Urol Nephrol ; 55(12): 3209-3215, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37093440

ABSTRACT

BACKGROUND/OBJECTIVES: There are few reports on the relationship between skipping breakfast and chronic kidney disease (CKD). We examined the skipping breakfast-CKD relationship and the mediation effects of metabolic diseases (obesity, hypertension, and diabetes) on this relationship. SUBJECTS/METHODS: We analyzed the data of 21,138 participants aged ≥ 40 years from the Korea National Health and Nutrition Examination Survey 2013-2018. Skipping breakfast was defined as rarely eating breakfast over the past year. CKD was defined as decreased kidney function expressed by an estimated glomerular filtration rate of < 60 mL/min/1.73 m2. We used a complex sample logistic regression model to examine the relationship between skipping breakfast and CKD. We used Baron and Kenny's approach to examine whether metabolic diseases work as a mediator within the skipping breakfast-CKD relationships. RESULTS: About 7.6% of participants skipped breakfast, and 5.5% had CKD. After adjusting for confounders, participants who skipped breakfast were at higher odds of having CKD (odds ratio 1.61; 95% confidence interval 1.07-2.42; p value 0.021) compared to those who did not skip breakfast. With full adjustments for confounders, skipping breakfast was not significantly associated with any metabolic diseases, while CKD was significantly associated with diabetes and hypertension. CONCLUSION: We found that middle-aged or older people who skipped breakfast had a significantly higher odds of having CKD compared to those who did not skip breakfast. However, metabolic diseases did not mediate the relationship between skipping breakfast and CKD.


Subject(s)
Diabetes Mellitus , Hypertension , Metabolic Diseases , Renal Insufficiency, Chronic , Middle Aged , Humans , Aged , Breakfast , Feeding Behavior , Nutrition Surveys , Hypertension/epidemiology , Renal Insufficiency, Chronic/epidemiology
18.
Int J Infect Dis ; 130: 101-107, 2023 May.
Article in English | MEDLINE | ID: mdl-36623793

ABSTRACT

OBJECTIVES: The annual incidence of Japanese encephalitis (JE) has increased markedly in South Korea since 2010. We hypothesized that this increase was associated with higher frequencies of JE virus in animals. METHODS: We analyzed 5201 serum samples collected from even-toed hoofed mammals (Artiodactyla species) across South Korea from 2008 to 2012 using a stratified two-stage probability approach. RESULTS: The highest annual incidence of human JE cases and deaths occurred in 2010. Cases increased from six (no deaths) in 2008-2009 to 26 cases (seven deaths) in 2010. The JE virus seroprevalence in deer and elk fawns increased from 2.4% in 2008 to 24.1% in 2009, and in wild boars, it increased from 19.3% to 55.0% in the same period, which preceded the surge of human cases. Furthermore, the seroprevalence in calves increased from 15.3% in 2008 to 35.8% in 2010, and that in lambs and goat kids, increased from 8.5% in 2009 to 26.2% in 2010, which coincided with the surge in humans. CONCLUSION: Our findings show that the increased incidence of human JE in South Korea was temporally associated with an increasing seroprevalence in the Artiodactyla species. Surveillance of sentinel animals may be useful to predict the emergence of JE in humans.


Subject(s)
Deer , Encephalitis Virus, Japanese , Encephalitis, Japanese , Humans , Animals , Sheep , Seroepidemiologic Studies , Encephalitis, Japanese/epidemiology , Encephalitis, Japanese/veterinary , Republic of Korea/epidemiology , Goats
19.
Trans R Soc Trop Med Hyg ; 117(3): 149-160, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36445309

ABSTRACT

Dengue fever has often been confused with other febrile diseases, with deterioration occurring in the later state. Many predictive models for disease progression have been developed, but there is no definite statistical model for clinical use yet. We retrieved relevant articles through Global Health, EMBASE, MEDLINE and CINAHL Plus. The Prediction Model Risk of Bias Assessment Tool was adopted to assess potential bias and applicability. Statistical analysis was performed using Meta-DiSc software (version 1.4). Of 3184 research studies, 22 were included for the systematic review, of which 17 were selected for further meta-analysis. The pooled data of predictive accuracy was as follows: the sensitivity was 0.88 (95% CI 0.86 to 0.89), the specificity was 0.60 (95% CI 0.59 to 0.60), the positive likelihood ratio was 2.83 (95% CI 2.38 to 3.37), the negative likelihood ratio was 0.20 (95% CI 0.14 to 0.0.29) and the diagnostic OR was 16.31 (95% CI 10.25 to 25.94). The area under the summary receiver operating characteristic curve value was 0.86 (SE=0.02) with 0.79 (SE=0.02) of the Cochran Q test value. The overall predictive power of models in this study was relatively high. With careful adaption and standardization, the implementation of predictive models for severe dengue could be practical in actual clinical settings.


Subject(s)
Severe Dengue , Humans , ROC Curve , Disease Progression , Sensitivity and Specificity
20.
Polymers (Basel) ; 14(23)2022 Dec 03.
Article in English | MEDLINE | ID: mdl-36501682

ABSTRACT

Zinc oxide performs as the best cure activator in sulfur-based vulcanization of rubber, but it is regarded as a highly toxic material for aquatic organisms. Hence, the toxic cure activator should be replaced by a non-toxic one. Still, there is no suitable alternative industrially. However, binary activators combining ZnO and another metal oxide such as MgO can largely reduce the level of ZnO with some improved benefits in the vulcanization of rubber as investigated in this research. Curing, mechanical, and thermal characteristics were investigated to find out the suitability of MgO in the vulcanization of rubber. Curing studies reveal that significant reductions in the optimum curing times are found by using MgO as a co-cure activator. Especially, the rate of vulcanization with conventional 5 phr (per hundred grams) ZnO can be enhanced by more than double, going from 0.3 Nm/min to 0.85 Nm/min by the use of a 3:2 ratio of MgO to ZnO cure activator system that should have high industrial importance. Mechanical and thermal properties investigations suggest that MgO as a co-cure activator used at 60% can provide 7.5% higher M100 (modulus at 100% strain) (0.58 MPa from 0.54 MPa), 20% higher tensile strength (23.7 MPa from 19.5 MPa), 15% higher elongation at break (1455% from 1270%), 68% higher fracture toughness (126 MJ/m3 from 75 MJ/m3), and comparable thermal stability than conventionally using 100 % ZnO. Especially, MgO as a co-cure activator could be very useful for improving the fracture toughness in rubber compounds compared to ZnO as a single-site curing activator. The significant improvements in the curing and mechanical properties suggest that MgO and ZnO undergo chemical interactions during vulcanization. Such rubber compounds can be useful in advanced tough and stretchable applications.

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