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Crack-free Al–Zn–Mg–Cu alloy, processed by laser powder bed fusion, displays a characteristic microstructure comprising fine equiaxed grains (EGs) and coarse columnar grains (CGs). Notably, the CGs show a high hardness compared to EGs due to the high density of in-situ precipitates. Analysis of mechanical properties takes into account the precipitates in the grain and hierarchical differences in grain morphologies near the melt pool boundary. Strengthening mechanisms are elucidated through synergistic hetero-deformation-induced strengthening, where multi-modal-sized EGs induce significant strain gradients within EG regions. Our findings demonstrate the potential to enhance strength of Al–Zn–Mg–Cu-based alloy in as-built state through architecting microstructures.

The tyrosinase inhibition effects of 23 marine-derived seaweeds harvested in Korea were screened to determine their potential as skin-whitening agents. Of the 23 species initially screened, the total phenolic (TP) content of brown, green, and red seaweeds were 7.62–280.11, 5.24–62.37, and 0.63–28.76 phloroglucinol equivalents (PGE) mg/g, respectively. Brown seaweed extracts exhibited much stronger inhibitory activities than green and red seaweed extracts. Among the brown seaweeds, Ecklonia cava had the highest TP content (280.11 PGE mg/g) and the strongest tyrosinase inhibitory effect with a half maximal inhibitory concentration (IC50) value of 4.38 μg/mL. The kinetics of tyrosinase inhibition, analyzed by Lineweaver–Burk plots, found E. cava extract to be a non-competitive inhibitor. This study’s results indicated that E. cava’s inhibition of tyrosinase may have potential applications in the cosmetic industry.

Abstract To investigate alteration of outer nuclear layer (ONL) and choroidal vascularity index (CVI) in different status of central serous chorioretinopathy (CSC). A retrospective review of 65 CSC eyes with subretinal fluid (manifest CSC) and 40 control eyes was conducted in a single tertiary university hospital. Differences in best-corrected visual acuity (BCVA), ONL, and CVI were compared. CVI was assessed both in the entire choroid (CVI-EC) and around the 1500 μm leakage area (CVI-1500). Measurements were repeated after the subretinal fluid resorption (quiescent CSC), and compared. CSC eyes showed worse BCVA, thinner ONL and greater CVI than controls. Quiescent CSC showed a recovery of ONL compared to the manifest CSC, along with the BCVA improvement. The resolution of the CSC revealed a decrease across all three choroidal areas (total, stromal and luminal), with a more pronounced reduction in the stromal than in the luminal choroidal area, leading to an increase in the CVI. This phenomenon was shown in both CVI-EC and CVI-1500. Conclusively, ONL thickness can be used as a quantitative biomarker for photoreceptor function in CSC. Increased CVI may reflect a disease activity. The stromal choroidal area is particularly sensitive in illustrating leakage from the choroidal vasculature.

Abstract Thermoelectric devices have received significant attention because of their potential for sustainable energy recovery. In these devices, a thermal design that optimizes heat transfer and dissipation is crucial for maximizing the power output. Heat dissipation generally requires external active or passive cooling devices, which often suffer from inevitable heat loss and heavy systems. Herein, the design of heat‐sink integrated thermoelectric legs is proposed to enhance heat dissipation without external cooling devices, realized by finite element model simulation and 3D printing of ternary silver chalcogenide‐based thermoelectric materials. Owing to the self‐induced surface charges of the synthesized AgBiSe2 (n‐type) and AgSbTe2 (p‐type) particles, these particle‐based colloidal inks exhibited high viscoelasticity, which enables the creation of complex heat‐dissipation architectures via 3D printing. Power generators made from 3D‐printed heat‐dissipating legs exhibit higher temperature differences and output power than traditional cuboids, offering a new strategy for enhancing thermoelectric power generation.

Abstract Software-Defined Networking (SDN) has emerged as an innovative networking method that offers effective management and remarkable flexibility. However, current SDN-based solutions primarily focus on static networks or concentrate on backbone networks, where network dynamics have minimal impact. The existing methods for placing flow entries in Software-Defined Networking (SDN)-based Internet of Things (IoT) systems exhibit shortcomings in accurately predicting outcomes and efficiently reducing table misses and associated performance metrics. This research introduces a new approach, specifically the mobility-aware adaptive flow entry placement scheme for SDN-based Internet of Things (IoT) environments, to address the mobility aspect of networks. The proposed scheme utilizes the Q-learning algorithm to predict the next possible location of end devices, while the cost-sensitive AdaBoost algorithm is employed to select heavy and active flows. As a result, efficient flow rules for incoming flows can be dynamically implemented without controller intervention. Extensive computer simulations demonstrate that this approach significantly enhances match probability and prediction accuracy while concurrently reducing the number of table misses and resource expenditure compared to existing schemes.

This study investigated cracking phenomena in 316L stainless steel (SS316L) and Inconel 718 (IN718) composition-graded material (CGM) additively manufactured by the direct energy deposition (DED) process. In order to prevent cracking in the CGM, thermodynamic analysis was performed to avoid the critical concentration for crack formation. Based on the local compositional detouring (LCD) method suggested by new approach, a crack-free CGM with a nonlinear combination of SS316L and IN718 was successfully fabricated with local additional elemental powder in the CGM defective region obtained using a multi-powder feeding system during the DED process.

Abstract Background Paralysis of medical systems has emerged as a major problem not only in Korea but also globally because of the COVID-19 pandemic. Therefore, early identification and treatment of COVID-19 are crucial. This study aims to develop a machine-learning algorithm based on bio-signals that predicts the infection three days in advance before it progresses from mild to severe, which may necessitate high-flow oxygen therapy or mechanical ventilation. Methods The study included 2758 hospitalized patients with mild severity COVID-19 between July 2020 and October 2021. Bio-signals, clinical information, and laboratory findings were retrospectively collected from the electronic medical records of patients. Machine learning methods included random forest, random forest ranger, gradient boosting machine, and support vector machine (SVM). Results SVM showed the best performance in terms of accuracy, kappa, sensitivity, detection rate, balanced accuracy, and run-time; the area under the receiver operating characteristic curve was also quite high at 0.96. Body temperature and SpO2 three and four days before discharge or exacerbation were ranked high among SVM features. Conclusions The proposed algorithm can predict the exacerbation of severity three days in advance in patients with mild COVID-19. This prediction can help effectively manage the reallocation of appropriate medical resources in clinical settings. Therefore, this algorithm can facilitate adequate oxygen therapy and mechanical ventilator preparation, thereby improving patient prognosis, increasing the efficiency of medical systems, and mitigating the damage caused by a global pandemic.

Obtaining extracts rich in pharmacological components from edible brown seaweeds is essential for their use as functional foods or therapeutic supplements. The present study demonstrated that the cold-water extract of Hizikia fusiformis (HF-C) with a unique composition, unlike hot-water (HF-H) or acid (HF-A) extracts, inhibited NF-κB activation, pro-inflammatory cytokines and glucose transporter expression, and inflammatory glycolysis more than HF-H or HF-A did. Oral administration of HF-C significantly inhibited dextran sodium sulfate-induced colitis in mouse, as evidenced by a decrease in disease activity index and inflammatory cytokine expression, and recovered colonic tissue E-cadherin expression and body weight. Notably, the anti-colitis effect of HF-C was greater than sulfasalazine, an inflammatory bowel disease (IBD) drug. Taken together, the higher anti-inflammatory action of HF-C was due to the different composition of fucoidan compared to the other extracts. Consequently, the results suggest that HF-C may be a therapeutic adjunct to the treatment of IBD.

Abstract To investigate the changes in outer nuclear layer (ONL) thickness during anti-vascular endothelial growth factor (VEGF) treatment in type 1 choroidal neovascularization (CNV) and its impact on vision. Type 1 CNV eyes (n = 94) were retrospectively compared to normal control eyes (n = 35). Along with best-corrected visual acuity (BCVA), the location of CNV, foveal ONL thickness, and subretinal fluid height were measured using optical coherence tomography (OCT) and analyzed. Visual outcome and OCT biomarkers were compared. As a result, the CNV group had thinner foveal ONL and worse BCVA compared to the control group. ONL thickness recovered partially along with visual improvement following 3 monthly initial loading doses of aflibercept injections, and it correlated with the final BCVA during the 1-year follow-up. Eyes achieved foveal ONL recovery over + 10 µm had lower subfoveal CNV (45.5%) and showed better visual outcomes than eyes with stationary ONL or suboptimal ONL recovery (76.0%, p = 0.012). In conclusion, type 1 CNV eyes that recovered foveal ONL thickness at initial loading of anti-VEGF demonstrated good final visual outcome during the 1-year follow-up. Monitoring the foveal ONL thickness during early anti-VEGF treatment can give information about the visual outcomes in type 1 CNV.

This paper proposes a novel method to impart intelligence to metal parts using additive manufacturing. A sensor-embedded metal bracket is prototyped via a metal powder bed fusion process to recognise partial screw loosening or total screw missing or identify the source of vibration with the assistance of artificial intelligence (AI). The digital metal bracket can recognise subtle changes in the screw fixation state with 90% accuracy and identify unknown sources of vibration with 84% accuracy. The von Mises stress distribution in the prototyped metal bracket is evaluated using a finite element analysis, which is learned by AI to match the real-time deformation analysis of the metal bracket in augmented reality. The proposed prototype can contribute to hyper-connectivity for developing next-generation metal-based mechanical components.

In this study, stainless steel 316L and Inconel 625 alloy powders were additively manufactured by using directed energy deposition process. And heat treatment effect on hardness and microstructures of the bonded stainless steel 316L/Inconel 625 sample was investigated. The microstructures shows there are no secondary phases and big inclusions near interfacial region between stainless steel 316L and Inconel 625 except several small cracks. The results of TEM and Vickers Hardness show the interfacial area have a few tens of micrometers in thickness. Interestingly, as the heat treatment temperature increases, the cracks in the stainless steel region does not change in morphology while both hardness values of stainless steel 316L and Inconel 625 decrease. These results can be used for designing pipes and valves with surface treatment of Inconel material based on stainless steel 316L material using the directed energy deposition.

Abstract Background To analyze the long-term effects of persistent subretinal fluid (SRF) on visual/anatomic outcomes according to the type of macular neovascularization (MNV) during relaxed treat-and-extend regimen with anti-vascular endothelial growth factor (anti-VEGF) agents in age-related macular degeneration (AMD) patients. Methods Patients with fovea-involving type 1 or type 2 MNV, treated with a relaxed treat-and-extend regimen for 2 years were retrospectively reviewed. Eyes with SRF observed more than three times per year were defined as the ‘persistent SRF (+) group’. To exclude the effects of IRF as much as possible, the eyes with persistent IRF were excluded. The effects of persistent SRF on the best-corrected visual acuity (BCVA), central subfield retinal thickness (CST), and changes in the photoreceptor layer (PRL) thickness and outer retinal bands (external limiting membrane, ellipsoid zone, and cone outer segment tip line) after anti-VEGF injection were analyzed for each MNV type. Results Seventy-seven eyes with type 1 MNV (44 eyes with persistent SRF) and 53 eyes with type 2 MNV (18 eyes with persistent SRF) were enrolled. Following a relaxed treat-and-extend regimen with anti-VEGF agents, BCVA and CST improved for each MNV type. In comparison between persistent SRF (+) and persistent SRF (−) group, there were no differences in the amount of change in BCVA and CST between the two groups for each MNV type during 2-year follow-up periods. In addition, there were no differences in the amount of reduction in PRL thickness and state of the outer retinal bands between the two groups for each MNV type. Conclusions Using a relaxed treat-and-extend regimen with anti-VEGF agents, persistent SRF did not have additional effects on visual and anatomic outcomes by 2 years, regardless of the MNV type.

Abstract A HPLC method was developed to assess the enhanced bioactivity of bioconverted Mori Folium (MF) extract and to apply a quality-control system. Liquid-liquid extraction was applied to observe changes in chemical composition through enzymatic bioconversion. The ethyl acetate layer was used for quality control of the anti-diabetic functional MF product. A high-performance liquid chromatography method was developed to analyze five marker compounds (syringaldehyde, trans-caffeic acid, morin 3-O-β-D-glucopyranoside, astragalin, and moracin M 3′-O-β-glucopyranoside) within 60 min. Optimized sample preparation was sonication for 44 min and a water-to-material ratio of 102.5 mL/g by response surface methodology. Comparing MF water extract, trans-caffeic acid and syringaldehyde contents were increased 1.89 times and 2.70 times at Viscozyme-bioconverted material by applying the developed method. This HPLC method can be used to control the quality of bioconverted MF based on suitable bioactive markers and also applied to develop anti-diabetic functional foods containing Mori Folium.

Abstract This retrospective, consecutive interventional study investigated the long-term clinical outcomes of combined vitrectomy with intraoperative dexamethasone implants for non-tractional refractory diabetic macular edema (DME). The study included 43 eyes from 39 participants with DME that had continued for more than 6 months despite repeated non-surgical treatment. Postoperative changes in best-corrected visual acuity (BCVA) and central macular thickness (CMT) were evaluated over 3 years. A Kaplan–Meier curve was obtained for any additional non-surgical treatment, and the average number of non-surgical treatments required for DME before and after surgery was compared. Other postsurgical complications were also investigated. The logMAR BCVA improved from 0.526 ± 0.417 (20/67) preoperatively to 0.294 ± 0.374 (20/39) 3 years postoperatively (p

Abstract Current quality control of Inonotus obliquus requires chromogen complex content limit of 10% in accordance with the State Pharmacopoeia of the Union of Soviet Socialist Republics. However, this causes ambiguous results, impeding precise quality control. To improve ambiguous quality control criteria, this study developed a new HPLC method using two novel marker compounds (inotodiol and 3β-hydroxylanosta-8,24-dien-21-al) to control the quality control of I. obliquus. The HPLC analysis was carried out in a C18 column with an isocratic elution of 95% acetonitrile at 210 nm. The developed method validated in terms of linearity, precision, accuracy, and recovery. The content criteria were established by the linear regression method and relative standard deviation method. As the results of the quantitative monitoring, 1.165 mg/g of inotodiol and 1.717 mg/g of 3β-hydroxylanosta-8,24-dien-21-al, calculated by the relative standard deviation method, were suggested new quality criteria. A new HPLC method was developed to improve current quality control of I. obliquus and new lower content criteria were proposed as a result of quantitative monitoring. Graphical abstract

A 39-year-old pregnant patient with acute appendicitis was planned for emergency laparoscopic appendectomy in the second trimester of pregnancy. Preoperative two-dimensional transthoracic echocardiography revealed asymptomatic cor triatriatum sinisiter (CTS), dividing left atrium into two chambers. There was no associated cardiac anomaly, wall motion abnormality, or pulmonary hypertension. We report the case of a pregnant patient with CTS who uneventfully underwent laparoscopic appendectomy without invasive cardiac monitoring using total intravenous anesthesia.

CoCrFeMnNi high-entropy alloys containing 1 at% carbon (C-HEAs) were additively manufactured using selective laser melting (SLM). Superior tensile properties of the as-built C-HEA (to previously reported ones) were achieved by utilizing multiple strengthening mechanisms (i.e. solid solution, grain refinement, dislocation density, and nano-precipitation) by this new manufacturing method. In particular, the SLM process could allow to maximize the strengthening effect of carbon addition to HEAs via finely distributed nano-carbides at the boundaries of solidification cellular structure. This work will open a new window to utilize the SLM process for enhanced mechanical properties of HEAs with great potential.

Background: The purpose of this study was to investigate the association between responses to intravitreal bevacizumab injection and renal function in diabetic macular edema (DME) patients. Methods: A retrospective study of the medical records of 104 treatment-naïve DME patients who received intravitreal bevacizumab injection (IVBI) was conducted. Based on the estimated glomerular filtration rate (eGFR, mL/min/1.73 m2), the participants were classified into three groups. Intergroup comparisons of the best-corrected visual acuity (BCVA) and central subfield retinal thickness (CST) changes were performed after three-monthly consecutive IVBIs. In the groups with decreased renal function, the response to further treatment with a different drug was investigated. Results: A total of 104 participants were included in the study: 60 participants in the preserved renal function group (eGFR ≥ 60), 25 participants in the moderate chronic kidney disease (CKD) group (30 ≤ eGFR < 60), and 19 participants in the severe CKD group (eGFR < 30). After three-monthly consecutive IVBIs, BCVA (p < 0.001) and CST (p < 0.001) were significantly improved only in the preserved renal function group. Following further treatment of patients with decreased renal function, the treatment results were significantly better in those who were switched to aflibercept or dexamethasone implant than in those who were maintained on IVBI. Conclusions: From this preliminary study, we observed that renal function might affect the response to IVBI treatment in patients with DME. In the case of a poor response to initial IVBI treatment for DME in patients with moderate to severe CKD, our study supports switching to the aflibercept or dexamethasone implant.

In this study, the effect of electroless Pd-P plating on the bonding strength of the Bi-Te thermoelectric elements was investigated. The bonding strength was approximately doubled by electroless Pd-P plating. Brittle Sn-Te intermetallic compounds were formed on the bonding interface of the thermoelectric elements without electroless Pd-P plating, and the fracture of the bond originated from these intermetallic compounds. A Pd-Sn solder reaction layer with a thickness of approximately 20 µm was formed under the Pd-P plating layer in the case of the electroless Pd-P plating, and prevented the diffusion of Bi and Te. In addition, the fracture did not occur on the bonding interface but in the thermoelectric elements for the electroless Pd-P plating because the bonding strength of the Pd-Sn reaction layer was higher than the shear strength of the thermoelectric elements.

Support Vector Machine (SVM) is an efficient machine learning technique applicable to various classification problems due to its robustness. However, its time complexity grows dramatically as the number of training data increases, which makes SVM impractical for large-scale datasets. In this paper, a novel Parallel Hyperplane (PH) scheme is introduced which efficiently omits redundant training data with SVM. In the proposed scheme the PHs are recursively formed while the clusters of data points outside the PHs are removed at each repetition. Computer simulation reveals that the proposed scheme greatly reduces the training time compared to the existing clustering-based reduction scheme and SMO scheme, while allowing the accuracy of classification as high as no data reduction scheme.

The fruits of Prunus mume, maesil (Rosaceae), have been widely used as a valuable source of foods and herbal medicines from ancient times in Northeast Asia. Specially, phenolic compounds of main compounds in maesil were reported to have various activities. This study aims to develop the simultaneous analytical method of nine phenolic compounds in maesil and to evaluate these compound contents in samples during the ripeness. Twenty-one species of samples and nine phenolic compounds were used for this study. In results, compounds 1–9 contents in unripe fruits were 0.16∼1.81 mg/g. However, these compounds in ripe samples were 0.09∼1.66 mg/g. Compounds 1–9 contents in ripe fruits were generally reduced rather than those in unripe fruits. Otherwise, the contents of compounds 2, 5, 8, and 9 in seed part were relatively higher than those in flesh part. In contrast, contents of compounds 1, 3, and 7 in flesh part were relatively higher than those in seed part. Generally, the contents of compounds 1–9 in unripe fruits were higher than those in ripe fruits. However, the contents of compounds 1–9 in each part (seed and fresh) of fruits were different according to species of compounds. It indicates that the selection of harvesting time and process part of fruits as the source of foods and medicines is important.

Fouling mitigation using chaotic advection caused by herringbone-shaped grooves in a flat membrane module is numerically investigated. The feed flow is laminar with the Reynolds number (Re) ranging from 50 to 500. In addition, we assume a constant permeate flux on the membrane surface. Typical flow characteristics include two counter-rotating flows and downwelling flows, which are highly influenced by the groove depth at each Re. Poincaré sections are plotted to represent the dynamical systems of the flows and to analyze mixing. The flow systems become globally chaotic as the groove depth increases above a threshold value. Fouling mitigation via chaotic advection is demonstrated using the dimensionless average concentration (c¯w*) on the membrane and its growth rate. When the flow system is chaotic, the growth rate of c¯w* drops significantly compared to that predicted from the film theory, demonstrating that chaotic advection is an attractive hydrodynamic technique that mitigates membrane fouling. At each Re, there exists an optimal groove depth minimizing c¯w* and the growth rate of c¯w*. Under the optimum groove geometry, foulants near the membrane are transported back to the bulk flow via the downwelling flows, distributed uniformly in the entire channel via chaotic advection.

Ginkgonis Semen (GS) is the seed of Ginkgo biloba Linné and a valuable material for herbal medicines and functional foods in China, Japan and Korea. The main bio-compounds of GS are GA, GB and GC like the leaves. There are many studies for the analysis of ginkgolides in the leaves or leaves extract of G. biloba because the leaves extract is a valuable material in pharmaceutical industries. However, there is no efficient analytical method for the quality control of GS based on the quantitation of ginkgolides because of matrix effect induced by different chemical composition. So, there are no content criteria of GS in Pharmacopoeia of Korea, Japan and China until now. This study aimed to develop HPLC method using ginkgolides based on the quantitation of GA, GB and GC for the quality control of GS with the optimization of sample preparation to enhance the analytical sensitivity and reproducibility. At first, defatting process using petroleum ether and liquid–liquid extraction were applied for sample preparation to remove matrix effect. The HPLC-ELSD method was developed with the mobile phase of a 0.5% aqueous acetic acid and methanol–acetonitrile solution (1:1 ratio) under gradient conditions. GA, GB and GC contents in GS were different between Korea and China. The mean quantity of Korean samples was 4.85 ± 2.33 μg/g GA, 48.38 ± 5.10 μg/g GB, and 37.83 ± 7.64 μg/g GC. Those contents of Chinese samples were higher than Korean samples as 9.39 ± 2.51 μg/g GA, 123.59 ± 26.24 μg/g GB and 53.39 ± 4.97 μg/g GC. It indicated that the discrimination of GS between Korea and China could be achieved by marker compound contents. Furthermore, the geographical discrimination of GS between Korea and China was confirmed by PCA using the quantitative data of marker compounds. By statistical analysis, the calculated content criteria of GS by regression method were 2.35 μg/g of GA, 29.20 μg/g of GB, and 27.75 μg/g of GC, based on dry weight. Thus, our HPLC method shows potential toward the development of a universal quality control methodology to quantify GS quality and origin.

Abstract Homotypic fusion of endoplasmic reticulum membranes is driven by atlastin GTPases; however, the underlying mechanism remains largely unknown. Here, using a FRET-based single-vesicle fusion assay with liposomes bearing the yeast atlastin Sey1p, we investigated the molecular mechanisms of atlastin-mediated membrane tethering and fusion. Although Sey1p-bearing proteoliposomes frequently underwent membrane tethering in a GTP hydrolysis-dependent manner as reported in studies using bulk assays, only a small fraction of the tethered liposomes proceeded to fusion. Strikingly, the rest of the tethered liposomes failed to fuse or dissociate. This stable tethering, however, did not require continued GTP hydrolysis because GTP omission and magnesium chelation did not disrupt tethering. Interestingly, an increased Sey1p density on the membrane markedly accelerated tethering but barely affected the fusion rate of the tethered liposomes, indicating that Sey1p requires additional factors to support efficient fusion in vivo. Finally, the assay also revealed that Sey1p-mediated liposome fusion occurs through hemifusion, suggesting the mechanistic conservation between biological membrane fusion events despite the existence of diverse fusogens.

Abstract Surface-mediated Al particles are synthesized by incorporating the stable fluoride reaction of Al-F on a pure Al surface in place of natural oxides. Al particles with fluoro-polymer directly adsorbed on the surface show a considerable capability to overcome limitations caused by the surface oxide. Here, we report that Al fluoride when spontaneously formed at the poly(vinylidene fluoride)/Al interface serves as an oxidation-protecting layer while also providing an efficient combustion path along which the internal Al rapidly reacts with external oxygen atoms. Both thermal oxidation and explosion tests of the poly(vinylidene fluoride)/Al particles show superior exothermic enthalpy energy and simultaneously rapid oxidation reactivity compared to those of Al2O3 passivated Al particles. It is clearly elucidated that the enhanced energetic properties of Al particles mediated by poly(vinylidene fluoride) originate from the extraordinary pyrolytic process of Al fluoride occurring at a low temperature compared to Al2O3 passivated Al. Hence, these results clarify that the surface mediation of Al particles can be significantly considered as advanced technology for many energetic applications.

A 25-year-old male patient who was infected with human immunodeficiency virus (HIV) underwent a condyloma excision under spinal anesthesia. The patient complained of suspicious postdural puncture headache. The patient did not respond to conservative management. Subsequently, the subdural hematoma (SDH) was found through magnetic resonance imaging. In response, an epidural blood patch was used to improve the symptoms and inhibit the enlargement of the SDH. The patient was discharged after it was confirmed that a headache had subsided without increasing SDH. Anesthesiologist should be aware of other causes of headaches after spinal anesthesia in HIV-infected patients and should carefully and accurately identify the cause.

Purpose. To investigate the associations between hyperreflective foci (HRF) on spectral-domain optical coherence tomography (SD-OCT) and early recurrence of macular edema after intravitreal dexamethasone (DEX) implantation in eyes with refractory diabetic macular edema (DME) to bevacizumab. Methods. Medical records of patients with refractory DME to bevacizumab, who underwent intravitreal DEX implantation and 12-month follow-up, were reviewed. Eyes in which central subfield thickness (CST) increased over 50 μm at 3 months compared with the first month after intravitreal DEX implantation were categorized into the early recurrence group, and the others were categorized into the late recurrence group. Best-corrected visual acuity (BCVA), CST, and number of HRF on SD-OCT were analyzed. Results. Twenty-nine eyes of 26 patients (16 eyes in the early recurrence group and 13 eyes in the late recurrence group) were included in this study. The numbers of HRF in entire retina, inner retina, and outer retina at baseline in the early recurrence group (11.38 ± 3.07 in entire retina, 5.44 ± 1.50 in inner retina, 5.94 ± 2.74 in outer retina) were significantly greater than those in the late recurrence group (7.54 ± 3.60 in entire retina, p=0.006; 4.08 ± 1.70 in inner retina, p=0.034; 3.46 ± 2.30 in outer retina, p=0.013). Multivariate logistic regression analysis showed that a higher number of HRF increased the risk of early recurrence after intravitreal DEX implantation (odds ratio in entire retina: 1.518, p=0.012; odds ratio in inner retina: 2.058, p=0.027; odds ratio in outer retina: 1.610, p=0.029). Conclusions. Higher baseline numbers of HRF on SD-OCT may be a predictive indicator of early recurrence of macular edema after intravitreal DEX implantation for DME.

We report a simple and environmentally friendly synthesis of polyethylenimine (PEI)-encapsulated Ag nanoparticles (AgNPs) by a direct electroreduction of solid AgCl. The AgNPs, characterized by field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray spectroscopy (EDS), revealed that AgNPs diameters (100–500 nm) depended on the loading of the AgCl precursor. Using cyclic voltammetry (CV), it was confirmed that the AgNPs had a catalytic effect on the electrochemical reduction of H2O2. The obtained AgNPs were subsequently used to construct an electrochemical H2O2 sensor exhibiting a low detection limit (1.66 μM) and a wide linear response range, with real-life tests indicating an insensitivity to common interferents and confirming the potential use of the developed technique in diverse applications.

The main purpose of this paper is to provide an in-depth analysis of the anatomy of China's automotive exports, relying on the literature on firm and product heterogeneity. For this purpose, we use highly disaggregated HS 8-digit product-category level data collected by the Chinese Customs Office for 2000 and 2008, and we distinguish between foreign firms, domestic public firms, and domestic private firms. We also decompose automotive products into autos and auto parts and components (P/C). We then calculate both the extensive margins – number of products exported – and intensive margins – average value of exports per product – of China's automotive exports. We estimate gravity equations to assess the determinants of China's exports of autos and auto P/C. Overall, our analysis yields a number of new, interesting stylized facts about China's automotive exports by confirming the need for taking into account different types of heterogeneity in analyzing international trade.

Purpose: To investigate the associations between early anatomical responses and intraocular pressure (IOP) changes in macular edema (ME) due to retinal vascular diseases treated with an intravitreal dexamethasone (DEX) implant. Methods: A retrospective review was conducted involving ME patients who underwent intravitreal DEX implantation. The eyes were divided into increased IOP (IIOP) or non-IIOP (nIIOP) groups according to the presence or absence of significant IOP elevation. Significant IOP elevation was defined by both the absolute value of IOP elevation (5 mmHg or higher) and an elevation percentage of the baseline IOP (an increase equal to 30% of the pre-injection IOP or higher). We analyzed the difference in central subfield thickness (CST) change according to the IOP elevation after DEX implantation. Relationships between IOP change and CST reduction after intravitreal DEX implantation were analyzed by Pearson correlation coefficients. Results: A total of 49 eyes, 29 with diabetic ME and 20 with ME due to retinal vein occlusion (RVO), were included in this study. Of the 49 eyes, 18 eyes (36.7%) were classified as IIOP group and 31 (63.3%) as nIIOP group. Significant differences in mean CST reductions over baseline one week after DEX implantation were observed between the groups. The degree of CST reduction from baseline to 1 week was significantly correlated with the degree of IOP change from baseline at 1 week and 1 month after intravitreal DEX implantation. Conclusions: In patients with ME due to retinal vascular diseases, we noted an early anatomical response significantly correlated with IOP change after intravitreal DEX implantation. Therefore, patients with favorable early anatomical responses to DEX implantation should be carefully monitored for IOP elevation.

Background: To evaluate long-term visual/anatomic outcome after anti-vascular endothelial growth factor (anti-VEGF) therapy in patients with fovea-involving fibrovascular pigment epithelium detachment (PED) presenting with choroidal neovascularization (CNV) on optical coherence tomography angiography (OCTA). Methods: Patients with fibrovascular PED or subretinal CNV confirmed by OCTA who were treated by a relaxed treat-and-extend regimen for 2 years were retrospectively reviewed. The best-corrected visual acuity (BCVA) and central subfield retinal thickness (CST) before and after anti-VEGF injection were analyzed. Furthermore, changes in photoreceptor layer (PRL) thickness and outer retinal bands in the fovea after injection were evaluated. Results: A total of 31 eyes with fibrovascular PED and 24 eyes with subretinal CNV were included. Following a relaxed treat-and-extend regimen with anti-VEGF agents, BCVA and CST were improved, and the PRL thickness was decreased significantly. There were no differences in BCVA, CST, changes in PRL thickness, or the status of outer retinal bands between the groups. However, the difference in the amount of decrease in PRL thickness between the two groups was increased at 2 years, and the slope tended to be steeper in the subretinal CNV group. Conclusions: Exudative age-related macular degeneration (AMD) with fibrovascular PED or subretinal CNV showed good visual/anatomic outcomes after anti-VEGF treatment, regardless of the CNV type. By 2 years, fibrovascular PED did not have an additional protective effect on the outer retina, compared with subretinal CNV over 2 years. Further follow-up study might be needed to conclude that fibrovascular PED has a protective effect on the surrounding photoreceptor area.

Rupture limited to the lobar bronchus from blunt trauma is especially rare, and the symptoms are light so diagnosis is difficult. In a patient who visited the hospital complaining of shortness of breath after falling down, atelectasis continued in the chest x-ray. Four days after visiting the hospital, a left upper lobar bronchial rupture was diagnosed through a bronchoscopy and 3 dimensional chest computerized tomography. When diagnosis is delayed in the case of a rupture limited to the lobar bronchus, bronchial obstruction can occur from the formation of granulation tissue, so regular monitoring is important. Therefore, when atelectasis continues after blunt trauma, it is important to differentially diagnose a lobar bronchial rupture through tests such as bronchoscopy.

Background: Dirofilaria immitis, a filarial nematode, is the most important parasite-affecting dogs, causing cardiopulmonary dirofilariasis. Current diagnostic tools for detecting D. immitis include morphological assays, antigen detection, and X-ray. Herein, we developed a method for the molecular detection of D. immitis in blood using polymerase chain reaction (PCR). Methods: The study was conducted at Eulji University, Republic of Korea in 2016. To detect D. immitis-specific gene regions, we aligned the cytochrome c oxidase subunit I (COI) genes of seven filarial nematodes and designed primers targeting the unique region. We used dog glyceraldehyde-3-phosphate dehydrogenase (GAPDH)-targeted primers as the internal control. We conducted PCR-amplified genomic DNA from canine blood samples. The products were confirmed by sequencing. Results: Gene alignment revealed a D. immitis COI-specific gene region, and the activity of designed primers was confirmed by PCR and sequencing. Plasmid DNA made from the PCR products was a positive control. The limit of detection for our method was 50 copies. The D. immitis COI and dog GAPDH genes could be discriminated from blood samples simultaneously. Conclusion: This study provides a method for highly specific and sensitive molecular diagnosis of D. immitis used as a diagnostic and therapeutic tool from the early stage of infection.

Marine-derived natural products from invertebrates comprise an extremely diverse and promising source of the compounds from a wide variety of structural classes. This study describes the discovery of five marine natural products with activity against Trypanosoma species by natural product library screening using whole cell in vitro assays. We investigated the anti-trypanosomal activity of the extracts from the soft corals and echinoderms living in Vietnamese seas. Of the samples screened, the methanolic extracts of several marine organisms exhibited potent activities against cultures of Trypanosoma brucei and T. cruzi (EC50 < 5.0 μg/mL). Among the compounds isolated from these extracts, laevigatol B (1) from Lobophytum crassum and L. laevigatum, (24S)-ergost-4-ene-3-one (2) from Sinularia dissecta, astropectenol A (3) from Astropecten polyacanthus, and cholest-8-ene-3β,5α,6β,7α-tetraol (4) from Diadema savignyi showed inhibitory activity against T. brucei with EC50 values ranging from 1.57 ± 0.14 to 14.6 ± 1.36 μM, relative to the positive control, pentamidine (EC50 = 0.015 ± 0.003 μM). Laevigatol B (1) and 5α-cholest-8(14)-ene-3β,7α-diol (5) exhibited also significant inhibitory effects on T. cruzi. The cytotoxic activity of the pure compounds on mammalian cells was also assessed and found to be insignificant in all cases. This is the first report on the inhibitory effects of marine organisms collected in Vietnamese seas against Trypanosoma species responsible for neglected tropical diseases.

We experienced a case of venous vessel wall entrapment between the introducer needle and the guide wire during an attempt to perform right internal jugular vein (IJV) catheterization. The guide wire was introduced with no resistance but could not be withdrawn. We performed ultrasonography and C-arm fluoroscopy to confirm the entrapment location. We assumed the introducer needle penetrated the posterior vessel wall during the puncture and that only the guide wire entered the vein; an attempt to retract the wire pinched the vein wall between the needle tip and the guide wire. Careful examination with various diagnostic tools to determine the exact cause of entrapment is crucial for reducing catastrophic complications and achieving better outcomes during catheterization procedures.

With the wide spread of Internet of Things, efficient communication between the nodes is getting more important. Constrained Application Protocol was developed to accommodate the resource-constrained nodes and low-power communication links. Being an Internet protocol, Constrained Application Protocol must adhere to congestion control, primarily to keep the backbone network stable. An advanced congestion control mechanism for Constrained Application Protocol, called Congestion Control/Advanced, has also been recently developed. In this article, we propose a new round trip time–based adaptive congestion control scheme, which further improves Congestion Control/Advanced by utilizing the retransmission count in estimating the retransmission timeout value and the lower bound in round trip time variation. An experiment is conducted based on Californium Constrained Application Protocol framework and real devices, and the performance is compared with Constrained Application Protocol, Congestion Control/Advanced, and an existing scheme. It reveals that the proposed scheme significantly increases the throughput and rate of successful transactions in comparison with the other schemes. The approach of utilizing the option field of Constrained Application Protocol enables the proposed scheme to be implemented without any conflict with the existing protocol and extra overhead.

Load Balancing (LB) is one of the most important tasks required to maximize network performance, scalability and robustness. Nowadays, with the emergence of Software-Defined Networking (SDN), LB for SDN has become a very important issue. SDN decouples the control plane from the data forwarding plane to implement centralized control of the whole network. LB assigns the network traffic to the resources in such a way that no one resource is overloaded and therefore the overall performance is maximized. The Ant Colony Optimization (ACO) algorithm has been recognized to be effective for LB of SDN among several existing optimization algorithms. The convergence latency and searching optimal solution are the key criteria of ACO. In this paper, a novel dynamic LB scheme that integrates genetic algorithm (GA) with ACO for further enhancing the performance of SDN is proposed. It capitalizes the merit of fast global search of GA and efficient search of an optimal solution of ACO. Computer simulation results show that the proposed scheme substantially improves the Round Robin and ACO algorithm in terms of the rate of searching optimal path, round trip time, and packet loss rate.

The individual parts of Morus alba L. including root bark, branches, leaves, and fruits are used as a cosmetic ingredient in many Asian countries. This study identified several anti-melanogenesis constituents in a 70% ethanol extract of M. alba leaves. The ethyl acetate fraction of the initial ethanol extract decreased the activity of tyrosinase, a key enzyme in the synthetic pathway of melanin. Twelve compounds were isolated from this fraction and their structures were identified based on spectroscopic spectra. Then, the authors investigated the anti-melanogenesis effects of the isolated compounds in B16-F10 mouse melanoma cells. Compounds 3 and 8 significantly inhibited not only melanin production but also intracellular tyrosinase activity in alpha-melanocyte-stimulating-hormone (α-MSH)-induced B16-F10 cells in a dose-dependent manner. These same compounds also inhibited melanogenesis-related protein expression such as microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-1 (TRP-1). Compound 3 modulated the cAMP-responsive element-binding protein (CREB) and p38 signaling pathways in α-MSH-activated B16-F10 melanoma cells, which resulted in the anti-melanogenesis effects. These results suggest that compound 3, isolated from M. alba leaves, could be used to inhibit melanin production via the regulation of melanogenesis-related protein expression.

In this paper we propose an energy efficient clustering algorithm for maximizing the lifetime of WSNs. The proposed scheme decides the cluster head based on the energy level of the nodes, while tree topology is adopted to connect the nodes inside each cluster. A new model for deciding an optimal number of clusters is also derived. Computer simulation reveals that the proposed scheme significantly extends the network lifetime and message delivery ratio compared to the existing schemes.

Recently, SSD caching is widely studied for VM-based systems. In this paper we propose a novel hypervisor-based SSD caching scheme, employing a new metric to accurately determine the demand on SSD cache space of each VM. Computer simulation confirms that it substantially improves the accuracy of cache space allocation compared to the existing schemes. It also allows comparable hit ratio as the existing schemes with less amount of SSD cache for the VMs.

Recently, the research of Hybrid ReRAM/MLC NAND SSD is rapidly expanding into the storage areas. Most existing researches of Hybrid SSD are based on a single storage, while the management of multiple nodes like HDFS is still immature. In this paper a new efficient cold data eviction scheme is proposed which is based on node congestion probability. Computer simulation reveals that the proposed scheme significantly reduces replication and recovery time in comparison to the existing replication schemes.

Wireless sensor network consisting of a large number of small sensors of low-power transceiver is effective for gathering data in a variety of environments. Since the network is built with low-cost sensor nodes of limited battery power, it is a challenging task to design an efficient routing scheme maximizing the network lifetime. In this paper, we propose a new clustering protocol reducing the energy taken for routing, and thus extending the network lifetime. The proposed scheme is based on a newly developed model of optimal number of clusters in the network with which the energy consumption can be minimized. It also includes a method of cluster-head rotation inside each cluster, which avoids the clustering operation during normal operation and evenly distributes the load among the nodes. The performance of the proposed scheme is compared with the clustering-based routing protocols, Low-Energy Adaptive Clustering Hierarchy (LEACH), LEACH-Centralized (LEACH-C), and Adaptive and Energy Efficient Clustering (AEEC) algorithm. Simulation results show that it significantly reduces energy consumption and improves network lifetime. It is thus expected to be effective for large-scale semantic sensor web.

RNA interference (RNAi), mediated by small non-coding RNAs (e.g., miRNAs, siRNAs), influences diverse cellular functions. Highly complementary miRNA-target RNA (or siRNA-target RNA) duplexes are recognized by an Argonaute family protein (Ago2), and recent observations indicate that the concentration of Mg2+ ions influences miRNA targeting of specific mRNAs, thereby modulating miRNA-mRNA networks. In the present report, we studied the thermodynamic effects of differential [Mg2+] on slicing (RNA silencing cycle) through molecular dynamics simulation analysis, and its subsequent statistical analysis. Those analyses revealed different structural conformations of the RNA duplex in Ago2, depending on Mg2+ concentration. We also demonstrate that cation effects on Ago2 structural flexibility are critical to its catalytic/functional activity, with low [Mg2+] favoring greater Ago2 flexibility (e.g., greater entropy) and less miRNA/mRNA duplex stability, thus favoring slicing. The latter finding was supported by a negative correlation between expression of an Mg2+ influx channel, TRPM7, and one miRNA's (miR-378) ability to downregulate its mRNA target, TMEM245. These results imply that thermodynamics could be applied to siRNA-based therapeutic strategies, using highly complementary binding targets, because Ago2 is also involved in RNAi slicing by exogenous siRNAs. However, the efficacy of a siRNA-based approach will differ, to some extent, based on the Mg2+ concentration even within the same disease type; therefore, different siRNA-based approaches might be considered for patient-to-patient needs.

Currently, sensor networks are widely used in various fields. Here secure operations are required for critical applications since the damages are significant if the network is compromised or disrupted. For the security of wireless sensor network, the earlier schemes typically employ asymmetric cryptography. These schemes are, however, often unsuitable for wireless sensor network due to the limited computational power and energy of the sensor nodes. To address this issue, various approaches have been developed, and the random key predistribution approach has been recognized as an effective approach. One shortcoming, however, is that a common key is not guaranteed to be found between any two nodes wanting to communicate. This paper proposes a new robust key predistribution scheme solving this problem, with which the security is not compromised even though the data exchanged between the nodes are tapped by an adversary. This is achieved by using the keys assigned based on the notion of eigenvalue and eigenvector of a square matrix of a pool of keys. Mathematical analysis and computer simulation reveal that the proposed scheme significantly reduces the overhead required for secure connectivity and energy consumption of sensor nodes compared to the existing approaches.

Energy efficiency is a critical issue for sensor network since the network lifetime depends on efficient management of the energy resource of sensor nodes. Particularly, designing energy efficient MAC protocol has a significant influence on the performance of wireless sensor network with regards to the energy. The existing MAC protocols developed for sensor network try to avoid energy waste during idle listening time by controlling the duty cycle of the transmission period. Since the traffic conditions are diverse, they may not always display improvements in energy consumption. In this paper we propose a new energy efficient MAC protocol called dynamic threshold MAC (DT-MAC), which employs a dynamic threshold for the buffer of each sensor node to maximize the energy efficiency regardless of specific network traffic condition. Here the packets are stored in the buffer, and then transmitted when the number of packets in the buffer exceeds the threshold dynamically decided according to the number of hops of the node from the source in the path of packet forwarding. The simulation results using OMNnet++ show that DT-MAC enables significant improvement in energy consumption compared to the existing MAC protocols. The proposed DT-MAC protocol also reduces the number of transmissions of control packets.

We report a derivative spectroscopic method for determining insulator-to-semiconductor transition during sol-gel metal-oxide semiconductor formation. When an as-spun sol-gel precursor film is photochemically activated and changes to semiconducting state, the light absorption characteristics of the metal-oxide film is considerable changed particularly in the ultraviolet region. As a result, a peak is generated in the first-order derivatives of light absorption (A′) vs. wavelength (λ) plots, and by tracing the peak center shift and peak intensity, transition from insulating-to-semiconducting state of the film can be monitored. The peak generation and peak center shift are described based on photon-energy-dependent absorption coefficient of metal-oxide films. We discuss detailed analysis method for metal-oxide semiconductor films and its application in thin-film transistor fabrication. We believe this derivative spectroscopy based determination can be beneficial for a non-destructive and a rapid monitoring of the insulator-to-semiconductor transition in sol-gel oxide semiconductor formation.