Poly(ethylene terephthalate) (PET) is synthesized via a rich ester bond between terephthalate (TPA) and ethylene glycol (EG). Because of this, PET degradation takes a long time and PET accumulates in ...the environment. Many studies have been conducted to improve PET degrading enzyme to increase the efficiency of PET depolymerization. However, enzymatic PET decomposition is still restricted, making upcycling and recycling difficult. Here, we report a novel PET degrading complex composed of Ideonella sakaiensis PETase and Candida antarctica lipase B (CALB) that improves degradability, binding ability and enzyme stability. The reaction mechanism of chimeric PETase (cPETase) and chimeric CALB (cCALB) was confirmed by PET and bis (2-hydroxyethyl terephthalate) (BHET). cPETase generated BHET and mono (2-hydroxyethyl terephthalate (MHET) and cCALB produced terephthalate (TPA). Carbohydrate binding module 3 (CBM3) in the scaffolding protein greatly improved PET film binding affinity. Finally, the final enzyme complex demonstrated a 6.5-fold and 8.0-fold increase in the efficiency of hydrolysis from PET with either high crystalline or waste to TPA than single enzymes, respectively. This complex could effectively break down waste PET while maintaining enzyme stability and would be applied for biological upcycling of TPA.
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•The novel poly (ethylene terephthalate) (PET) hydrolytic complex was developed for waste PET degradation.•PET degradation complexes were better binding ability with PET than free enzymes.•This complex retained enzyme activity and stability during PET depolymerization.•The combined complex could degrade high crystalline PET and waste PET.
This paper proposes a highly parallel variable block size full search motion estimation algorithm with concurrent parallel reduction (CPR) on graphics processing unit (GPU) using compute unified ...device architecture (CUDA). This approach minimizes memory access latency by using high-speed on-chip memory of GPU. By applying parallel reductions concurrently depending on the amount of data and the data dependency, the proposed approach increases thread utilization and decreases the number of synchronization points which cause latency. Experimental results show that the proposed approach achieves substantial improvement up to 92 times than the central processing unit (CPU) only counterpart.
Little is known about the changes in autonomic function during spinal anaesthesia in type 2 diabetic patients. The purpose of the study was to assess the influence of spinal anaesthesia on the heart ...rate variability in type 2 diabetic patients according to the glycated hemoglobin (HbA1c) level.
Sixty-six patients who were scheduled for elective orthostatic lower limb surgery were assigned to three groups (n = 22, each) according to HbA1c; controlled diabetes mellitus (HbA1c < 7 %), uncontrolled diabetes mellitus (HbA1c > 7 %) and the control group. The heart rate variability was measured 10 min before (T0), and at10 min (T1), 20 min (T2) and 30 min (T3) after spinal anaesthesia.
Before spinal anaesthesia, total, low-and high-frequency power were significantly lower in the uncontrolled diabetec group than in other group (p < 0.05). During spinal anaesthesia, total, low- and high-frequency powers were did not change in the uncontrolled diabetec group while the low-frequency power in the controlled diabetec group was significantly depressed (p < 0.05). The ratio of low-to high-frequency was comparable among the groups, while it was reduced at T1-2 than at T0 in all the groups. The blood pressures were higher in the uncontrolled diabetec group than in the other groups.
Spinal anaesthesia had an influence on the cardiac autonomic modulation in controlled diabetec patients, but not in uncontrolled diabetec patients. There were no differences in all haemodynamic variables during an adequate level of spinal anaesthesia in controlled and uncontrolled type 2 DM.
ClinicalTrials.gov NCT02137057.
Adding boron to stainless steel for sintering affects the densification behavior and microstructure, including the formation of the precipitated phase. This study investigated the effects of boron on ...densification for sintering via master sintering curves and microstructural analysis based on image processing. Mixtures of different boron contents in stainless steel powder were employed. The in situ shrinkages during sintering were used to construct master sintering curves for each mixture. The densification behaviors were analyzed according to various aspects, including the apparent activation energy. The results confirmed greater densification with the addition of boron, which decreased the melting point. The microstructural evolution was considered because the precipitated phase, which included CrxBy, reduced the mechanical strength. An image processing method was used to identify the formation of the precipitated phase in the microstructure based on the intensity difference. The algorithm of the image processing method was verified with an electron probe micro-analyzer. The effects of boron on sintering were then quantified according to the CrxBy phase. The results confirmed the increased formation of the CrxBy phase. The low intensity of the CrxBy phase according to the image processing method was validated by X-ray diffraction and transmission electron microscopy.
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•Densifications with B contents were analyzed through master sintering curve.•Densification rate and quantity with B contents were evaluated.•Image processing method to quantify the CrxBy phase was developed.•The increase of CrxBy phase with B was quantitatively verified.
The powder processing methods including powder metallurgy (P/M) and powder injection molding (PIM) techniques for tungsten (W)–rhenium (Re) were employed to produce a W–Re rocket nozzle. The ...composition of W–Re was determined by 25wt.% of Re to avoid the formatting brittle sigma (σ) phase. The samples for analysis of the densification behavior on sintering were prepared by die pressing and cold isostatic pressing (CIP). The feedstock for the PIM process was produced by mixing the W–25wt.% Re powder and binder system based on a wax-polymer with an optimum solid loading through the twin-extruder mixer. The injection molded specimens were debound to extract and decompose the binders via the solvent and thermal debindings. The debound samples were sintered in a hydrogen atmosphere. After sintering, hot isostatic pressing (HIP) was carried out in an argon atmosphere to enhance the density.
The dilatometry experiments were performed to analyze and predict a densification behavior during sintering. The master sintering curve (MSC) model was used to characterize the densification behavior with a minimal set of preliminary experiments. The mechanical properties were evaluated through microstructure and chemical composition measured by EDX–SEM and X-ray diffraction (XRD).
Finally, the eroding test was conducted using the W–25wt.% Re rocket nozzle produced by PIM under the high temperature. After carrying out erosion tests, the erosion rate, hardness and microstructure were evaluated.
•The powder processing methods for W-25wt%Re were developed, and the rocket nozzles produced by PIM were evaluated by erosion test.•In many respects including density, microstructure, carbon contents, and sigma-phase, the rocket nozzle produced by PIM has the outstanding properties.
A semiconductor laser module consists of a LD (laser diode) chip that generates a laser beam, two cylindrical lenses to collimate the laser beam, a high-reflection mirror to produce a large output by ...collecting the laser beam, a collimator lens to guide the laser beam to an optical fiber and a protection filter to block reflected laser light that might damage the LD chip. The cylindrical lenses used in a semiconductor laser module are defined as FACs (fast axis collimators) and SACs (slow axis collimators) and are attached to the system module to control the shape of the laser beam. The FAC lens and the SAC lens are made of a glass material to protect the lenses from thermal deformation. In addition, they have aspheric shapes to improve optical performances. This paper presents a mold core grinding process for an asymmetrical aspheric lens and a GMP (glass molding press), what can be used to make aspheric cylindrical lenses for use as FACs or SACs, and a protection filter made by using IAD (ion-beam-assisted deposition). Finally, we developed the aspheric cylindrical lenses and the protection filter for a 10-W semiconductor laser module.
Medicinal herbs are increasingly used in the search for safe and efficient drug candidates for hepatitis C virus infection. In this study, we have investigated the anti-HCV effect of compounds from ...Mori Cortex Radicis. During a screening for extracts with anti-HCV affinity from medicinal plants (173 species), the methanol extract of Mori Cortex Radicis was selected. Fractionation of the extract by monitoring antiviral activity with a replicon cell-based assay resulted in the isolation of five compounds, mulberroside C ( 1), moracin P ( 2), moracin O ( 3), moracin M ( 4) and mulberrofuran K ( 5) from the ethyl acetate-soluble fraction. Compounds 1 approximately 4 showed significant inhibitory activities. Compounds 2 and 3 showed potent inhibitory activity (IC (50) 35.6 microM, 80.8 microM, respectively) in the replicon cell assay, which was confirmed by NS3 helicase inhibitory activity (IC (50) 42.9 microM, 27.0 microM, respectively).
To investigate the association between Bell's palsy and stroke according to the different types of stroke, using a sample cohort based on the national Korean population.
Individuals aged ≥ 20 years ...were collected from the Korean National Health Insurance Service National Sample Cohort between 2002 and 2013. We extracted the data for Bell's palsy patients (n = 3658) and 1:4 matched controls (n = 14,632) and analyzed the occurrence of hemorrhagic or ischemic stroke in both groups. Matching was performed on the basis of age, gender, income, and region of residence. For Bell's palsy, we included only participants who received the diagnosis (ICD-10 code, G510) 2 or more times via ambulatory visits for the same episode with steroid treatment. Patient admission histories were used to identify occurrences of hemorrhagic stroke (I60, I61 and I62) and ischemic stroke (I63). Adjusted hazard ratios were calculated using stratified Cox proportional hazard models for the Charlson comorbidity index and 95% confidence intervals (CIs). For the subgroup analyses, we divided the participants by age, sex, and each time period after the onset of Bell's palsy (≤1 year, 1 to 2 years, 2 to 3years, > 3years).
The risk of ischemic stroke was significantly increased in Bell's palsy patients compared to that in the controls (adjusted HR = 1.74, 95% CI = 1.38–2.19, P < 0.001). In the subgroup analyses, a significant association between two clinical disorders was observed in patients aged ≥ 50 years old, regardless of gender. The risk of ischemic stroke was significantly increased, especially within 2 years after Bell's palsy. In contrast, the risk of hemorrhagic stroke was not significantly increased.
There is an association of Bell's palsy with ischemic stroke but not with hemorrhagic stroke.
Background/Aims: Long-term use of acid suppressants such as proton pump inhibitors (PPIs) and histamine 2 receptor antagonist (H2RA) has been associated with the risk of osteoporotic fracture. Acid ...suppressants and muco-protective agents (MPAs) are often used together as anti-ulcer agents. We evaluated the association between the risk of osteoporotic fracture and the combined use of these anti-peptic agents.
Methods: A population-based case-control study was conducted by analyzing the Korean National Health Insurance Data from 2014 to 2020. Patients who had been prescribed anti-peptic agents, such as PPI, H2RA, or MPA, were included. Considering the incidence of osteoporotic fractures, the case group (n = 14,704) and control group (n = 58,816) were classified by 1:4 matching based on age and sex.
Results: The use of all types of anti-peptic agents was associated with an increased risk of osteoporotic fractures (PPI: hazard ratio HR, 1.31; H2RA: HR, 1.44; and MPA: HR, 1.33; all p < 0.001). Compared to PPI alone, the combined use of “PPI and H2RA” (HR, 1.58; p = 0.010) as well as “PPI, H2RA, and MPA” (HR, 1.71; p = 0.001) was associated with an increased risk of osteoporotic fracture. However, compared with PPI alone, “MPA and PPI or H2RA” was not associated with an increased risk of osteoporotic fracture.
Conclusions: This study found that the combined use of “PPI and H2RA” was associated with a higher risk of osteoporotic fractures. In cases where deemed necessary, the physicians may initially consider prescribing the combination use of MPA.
Background/Aims: Mucoprotective agents, such as eupatilin, are often prescribed to prevent gastrointestinal (GI) bleeding in addition to an acid suppressant despite the absence of a large-scale ...study. We evaluated the additional effect of eupatilin on the prevention of GI bleeding in both the upper and lower GI tract in concomitant aspirin and acid suppressant users using the nationwide database of national claims data from the Korean National Health Insurance Service (NHIS).
Methods: An aspirin cohort was constructed using the NHIS claims data from 2013 to 2020. Patients who manifested with hematemesis, melena, or hematochezia were considered to have GI bleeding. A Cox proportional hazards regression model was used to determine the risk factors for GI bleeding associated with the concomitant use of GI drugs and other covariates among aspirin users.
Results: Overall, a total of 432,208 aspirin users were included. The concurrent use of an acid suppressant and eupatilin (hazard ratio HR = 0.85, p = 0.016, vs. acid suppressant only) was a statistically significant preventive factor for GI bleeding. Moreover, a more than 3-month duration (HR = 0.88, p = 0.030) of acid suppressant and eupatilin prescription (vs. acid suppressant only) was a statistically significant preventive factor for GI bleeding.
Conclusions: Eupatilin administration for ≥ 3 months showed additional preventive effect on GI bleeding in concomitant aspirin and acid suppressant users. Thus, cotreatment with eupatilin with a duration of 3 months or longer is recommended for reducing GI bleeding among aspirin plus acid suppressant users.
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