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Gold nanoparticles (AuNPs) were surface-engineered with a cationic corona to enhance the incorporation of photosensitizers for photodynamic therapy (PDT). The cationic corona composed of poly(2-(dimethylamino)ethyl methacrylate) was atom transfer radical-polymerized on the surface of the AuNPs. The cationic corona of the engineered surface was characterized by dynamic light scattering, electron microscopy, Raman spectroscopy, and mass spectroscopy. Chlorin-e6 (Ce6) incorporated onto the surface-engineered AuNPs exhibited higher cell incorporation efficiency than bare AuNPs. Ce6-incorporated AuNPs were confirmed to release singlet oxygen upon NIR irradiation. Compared to Ce6, Ce6-incorporated AuNPs exhibited higher cellular uptake and cytotoxicity against cancer cells in an irradiation time-dependent manner. Near-infrared-irradiated animals administered Ce6-incorporated AuNPs exhibited higher levels of tumor suppression without noticeable body weight loss. This result was attributed to the higher localization of Ce6 at the tumor sites to induce cancer cell apoptosis. Thus, we envision that engineered AuNPs with cationic corona can be tailored to effectively deliver photosensitizers to tumor sites for photodynamic therapy.

In a DC microgrid, a conventional solution for the primary control is droop control, which is achieved by imposing a virtual impedance on each converter. Its main drawbacks are the current sharing inaccuracy and the voltage deviation. To address these problems, we propose a robust distributed cooperative controller, which is an alternative to the droop mechanism. The controller is distributed in the sense that each one exchanges information with its neighboring converters, and hence no central controller is required. It is robust in the sense that parameters of power sources or load are not directly used to determine the controller parameters. A rigorous mathematical analysis is presented to guarantee the stability of the proposed controller, and simulation results are included to validate it.

The upcoming ubiquitous electronics era, which will find widespread popularity of flexible/wearable electronics, self-powered devices, and the Internet of Things (IoT), stimulates us to develop a new concept of advanced power sources beyond currently available battery technologies. Among several approaches to reach this goal, printed power sources with various form factors and flexibility have recently garnered considerable attention as a promising system. The form factor-free, printed power sources, driven by their design diversity, shape/performance compatibility with electronics, and scalable/low-cost processability, enable monolithic/seamless integration with complex/unconventional-shaped electronic devices, in comparison to conventional rigid/bulky counterparts. Here, we review the current status and challenges of the form factor-free, printed power sources, with a focus on their materials development. Various printing techniques and their process parameters exploited for the printed power sources are briefly described. Subsequently, ink materials and chemistry of major cell components are discussed. Based on the understanding of the printing techniques and materials, applications of the printed power sources are overviewed to highlight their exceptional shape aesthetics and electrochemical characteristics in the integrated electronics. Finally, we propose development directions and outlook of the form factor-free, printed power sources as a device-customized energy storage system, along with prospects of their future applications.

Summary The forthcoming smart and ubiquitous electronics era presents significant interest in wireless interconnectivity and shape aesthetics. To fulfill this demand, a new class of advanced power sources with various form factors that are different from existing commercial ones is needed. Printed power sources have recently garnered substantial attention because of their design diversity, shape and performance compatibility with electronics, and scalable and low-cost processability. They are fabricated directly on complex-structured objects via application-customized printing techniques, enabling monolithic integration and electrochemical coupling with target devices. In this Perspective, we describe the current status and challenges of printed power sources, focusing on their role as built-in power sources. Various printing techniques and ink materials and chemistry of electrodes and electrolytes are discussed as key enabling factors. Noteworthy progress in printed built-in power sources is reviewed to highlight their design diversity and electrochemical superiority. Finally, development direction and outlook of printed built-in power sources are discussed in conjunction with their application fields.

Digital Hologram is a very high-value-added image content, whose intellectual property should be protected for its distribution. Therefore its watermarking technology has become much important. This paper is to propose a training scheme of a deep neural network to perform a digital watermarking for a digital hologram. We construct various training datasets according to the distribution of holograms and train them on the proposed network. The network consists of preprocessing networks for both host data and watermark, watermark embedding network, and watermark extraction network, all of which consist of simple convolutional neural network (CNN) modules. The dataset is constructed with the digital holograms from JPEG Pleno and they are classified by distribution of the hologram pixel values. The network is trained with each of the classified holograms. With each of the trained weight sets, the invisibility and watermark extraction rate are calculated and compared with the results from testing the test dataset that has not been used for training. From the result, we explain the effects of the data distribution of the training dataset on the invisibility and robustness of the watermarking to present the best training scheme for a digital watermarking of a digital hologram.

It is unclear whether depression is linked to nonalcoholic fatty liver disease (NAFLD). The purpose of this study was to examine the association between depression and NAFLD and whether the association is partly explained by insulin resistance or inflammation.Subjects consisted of 4,688 adults who participated in the 2016 Korea National Health and Nutrition Examination Survey. Depression was defined by Patient Health Questionnaire-9 score ≥ 10 or a previous diagnosis of depression. NAFLD was defined by hepatic steatosis index36. Insulin resistance was assessed by triglycerides and glucose (TyG) index. Inflammation was measured with C-reactive protein (CRP).Depression had a significant association with TyG index (p = 0.005), but not with CRP. Depression was a significant predictor of NAFLD (OR = 1.63; 95% CI, 1.26-2.10; p0.001). Adjustment for sociodemographic features and waist circumference did not substantially affect the results. Further adjustment for comorbidities reduced the estimate for depression by 23% (OR = 1.56; 95% CI, 1.18-2.06; p = 0.002). Inclusion of CRP in a fully adjusted model did not affect the results. Addition of the TyG index decreased the estimate for depression by 28% (OR = 1.39; 95% CI, 0.88-2.19; p = 0.161), and the resulting estimate became no longer significant. The TyG index remained the independent predictor of outcome.The absence of a structured diagnostic interview for depression and histological diagnosis of NAFLD.These data support an association of depression with NAFLD. Insulin resistance seems to play a major role in modulating the association between depression and NAFLD risk.

Although nanofibrous meshes are considered promising cultivation beds for maintaining cell differentiation, 3D cultivation is not possible because their nanoporous structures impede cell infiltration. To facilitate transverse cell migration across nanofibrous meshes, electrospun nanofibers are prepared with structures that vary in response to red laser light. Polyoxalate (POX), composed of oxalate linkers and oligomeric caprolactone, is synthesized and electrospun into fibrous meshes with a photosensitizer (chlorin e6, Ce6). These meshes exhibit morphological and chemical changes upon laser irradiation, and mass erosion rates of the meshes are faster after laser irradiation. Cell cultivation on POX meshes reveals that red laser effectively facilitates traverse migration of the cells without affecting cell viability. The use of light-triggered change of meshes is envisioned to promote the migration of cells during 3D matrix cultivation.

The dynamic average consensus problem for a group of agents is considered. Each agent in the group is supposed to estimate the average of inputs applied to all agents and the estimation should be done in a distributed way. By reinterpreting the proportional integral type estimator, a new structure for the average estimator which can embed the internal model of inputs is proposed and conditions which result in the zero estimation error in the steady state are derived. We present constructive design procedures for the cases of constant inputs and time-varying inputs employing the root locus for the former and LQR-based design for the latter. The theory is validated through numerical simulations.

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis affecting medium- or small-sized arteries. Its diagnosis may be delayed because it is a rare disease, and patients presenting with PAN demonstrate variable clinical manifestations and non-specific laboratory abnormalities. Gastrointestinal involvement occurs in 14∼65% of patients with PAN and is a significant cause of morbidity and mortality. Thus, early diagnosis is very important in PAN with gastrointestinal involvement. We report two cases of rapidly progressive PAN presenting with abdominal pain, having failed conservative treatment.

Background It is important to identify candidates who would benefit from target agent chemotherapy in advanced NSCLC patients. The purpose of this study is to evaluate the feasibility of DCE-MRI for early response evaluation in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) treatment in patients with NSCLC. Methods Seven patients were prospectively enrolled who have pathologically-proven NSCLC with EGFR mutations or at least 2 of the following factors; adenocarcinoma, female, or never-smokers. Patients were treated with gefitinib or erlotinib and the start of chemotherapy was denoted day 0. DCE-MRI was performed at day-1, day+7, and day+28. Longitudinal changes of perfusion parameters were quantified and compared to Response Evaluation Criteria in Solid Tumors (RECIST) results. Results Quantitative perfusion parameters; Ktrans, ve and vp of the lung cancer showed a significant decrease at day+7 (P=0.016), but no further significant decrease between day+7 and day+28 (P>0.05). Semiquantitative markers for tumor enhancement curve pattern; EA (enhancement amplitude), MS (maximum slope), and AUC (area under the curve) also showed a significant decrease at day+7 (P=0.016, 0.031, and 0.016, respectively), but no further significant decrease between day+7 and day+28 (P>0.05). When RECIST applied, all patient was in the stable disease at day+7 and three patients showed partial response (PR) at day+28. All seven patients showed PR by the 3-month follow-up. Conclusions Perfusion parameters may be used as an early non-invasive imaging biomarker for the response evaluation of target agent treatment in NSCLC.

In this paper, we improve a distributed load sharing controller for dc microgrids by using a dynamic average consensus(DAC). The controller of each converter exchanges information with its neighboring converters, hence no central controller is required. Simulation results are included to validate the proposed method.

Many citrus cultivars have the polyembryony trait that develops many nucellar embryos alongside a single zygotic embryo in an individual seed by sporophytic apomixis. This unique botanical trait hinders citrus breeding by genetic hybridization and affects breeding efficiency and cost. Techniques to efficiently identify nucellar and zygotic individuals in citrus are still very limited. For a systematic and targeted citrus breeding program, we collected 101 citrus genetic resources and determined their embryo types, which revealed 22 monoembryo, 54 polyembryo, and 25 mixed types. We also developed 17 simple sequence repeat (SSR) markers showing polymorphism among the genetic resources from the public resources and our own comparative genome analysis. Seventeen SSR markers detected a total of 181 alleles, ranging from 5 to 16 alleles per locus. The average polymorphism information content value was 0.67, ranging from 0.43 to 0.84. Genetic cluster analysis based on similarity matrices of alleles revealed that several genetic resources of the genus Citrus were fragmented and/or scattered throughout the entire dendrogram, not forming unique groups, due to frequent natural or intended genetic crossings. Application of these polymorphic SSR markers to F1 individuals derived from several genetic crosses using polyembryonic citrus cultivars as a female parent revealed that the polyembryony trait decreased the breeding efficiency due to the poor occurrence rate of zygotic individuals. Therefore, our results suggest that identification of nucellar and zygotic embryo-derived F1 individuals using SSR markers as a genotyping technology may be a powerful tool for establishing a systematic molecular breeding program in citrus.

This paper considers a distributed load sharing problem in dc microgrids. A common solution to this problem is to introduce a virtual impedance and this is called the droop control in the literature. In this paper, we propose an alternative load sharing controller which replaces the droop mechanism. The load sharing is achieved by incorporating a consensus term in the controller so that the per-unit current of each converter becomes identical. The controller is distributed in the sense that the controller of each converter exchanges information with its neighboring converters, hence no central controller is required. Simulation results are included to validate the proposed controller.

Charged phospholipids are employed to formulate liposomes with different surface charges to enhance the permeation of active ingredients through epidermal layers. Although 3D skin tissue is widely employed as an alternative to permeation studies using animal skin, only a small number of studies have compared the difference between these skin models. Liposomal delivery strategies are investigated herein, through 3D skin tissue based on their surface charges. Cationic, anionic, and neutral liposomes are formulated and their size, zeta-potential, and morphology are characterized using dynamic light scattering and cryogenic-transmission electron microscopy (cryo-TEM). A Franz diffusion cell is employed to determine the delivery efficiency of various liposomes, where all liposomes do not exhibit any recognizable difference of permeation through the synthetic membrane. When the fluorescence liposomes are applied to 3D skin, considerable fluorescence intensity is observed at the stratum cornea and epithelium layers. Compared to other liposomes, cationic liposomes exhibit the highest fluorescence intensity, suggesting the enhanced permeation of liposomes through the 3D skin layers. Finally, the ability of niacinamide (NA)-incorporated liposomes to suppress melanin transfer in pigmented 3D skin is examined, where cationic liposomes exhibit the highest degree of whitening effects.

Objectives With the rapid increase in the prevalence of diabetes, the age groups of diabetic patients are becoming diversified. This study will examine the degree of obesity, insulin resistance, and insulin secretion ability among patients first diagnosed with diabetes according to age and gender. Methods The subjects of this study included 616 patients who were first diagnosed with diabetes during a routine physical examination. This sample was obtained from a total of 28,075 adults aged 19 years and older who received the examination among 33,829 participants in the Korea National Health & Nutrition Examination Survey (KNHANES) from 2007–2010. The subjects were categorized by age into young age (age: 19 – 39 years), middle age (age: 40 – 59 years), and old age (age: 60 years and older). The degree of obesity was categorized according to body mass index (BMI) into normal weight (BMI: 18.5 ∼ 22.9), overweight (BMI: 23 ∼ 24.9), and obesity (BMI: 25 or above). Insulin resistance was evaluated by homeostatic model assessment of insulin resistance (HOMA-IR). Results It was found that 14.1% (n = 87) of a total of 616 subjects (324 men, 292 women) were in the young age group, 43.8% (n = 270) were in the middle age group, and 42.1% (n = 259) were in the old age group. In addition, 83.3% of men that were overweight or obesity were in the young age group, while 79.2% and 60.5% were in the middle age and old age groups, respectively. A total of 82.2% of women that were overweight or obesity were in the young age group, while 79.5% and 77% were in the middle age and old age groups, respectively. For men, the more obesity they were in all age groups, the higher their HOMA-IR. For women, the more obesity they were in the young age and middle age groups, the higher their HOMA-IR; however, women in the old age group showed the highest HOMA-IR when they were of normal weight. Conclusion Among diabetic patients first diagnosed with the disease in Korea, the youth population had the highest obesity rate. Insulin resistance increases as an individual's weight increases among those patients who are first diagnosed with diabetes; the only exception noted is for elderly women.

LiCl is widely prescribed for bipolar disorder but adversely associated with a higher incidence of increased body weight. Here, we investigated effects and underlying mechanisms of LiCl on lipid accumulation. LiCl induced dose-dependent lipid accumulation in HepG2 and RAW264.7 cells under normal as well as high glucose conditions. LiCl exposure additionally promoted lipid accumulation in livers of zebrafish. SB216763, a specific GSK-3β inhibitor, did not affect lipid accumulation in HepG2 cells. Expression of key lipogenic enzymes, such as FAS and aP2, as well as SR-B1 were increased in RAW264.7 cells. LiCl enhanced FAS, ACC and SCD-1 mRNA levels while suppressing CPT-1 in HepG2 cells. LiCl stimulated DNA binding activities of SREBP-1c and ChREBP. LiCl activated AMPK phosphorylation but the AMPK inhibitor, AICAR, did not suppress LiCl-induced lipid accumulation in RAW264.7. LiCl, but not SB216763, induced a significant increase in ROS in RAW264.7 and HepG2 cells. NOX activity was dose-dependently enhanced by LiCl. Furthermore, NOX-1, NOX-2 and DUOX-1 mRNA levels were upregulated at an early stage of LiCl stimulation. LiCl-induced lipid accumulation was suppressed by the antioxidant, NAC, and inhibitors of NOX, DPI and APO. Phosphorylation and transcriptional activity of CREB were enhanced by LiCl. The cell-permeable cAMP analog, di-butyryl cAMP, not only promoted lipid accumulation itself but also LiCl-induced lipid accumulation in RAW264.7 cells. H-89, a PKA inhibitor, suppressed CREB activation, lipid accumulation and NOX activity in RAW264.7 cells. Our results indicate that LiCl stimulates lipid accumulation in hepatocyte and macrophage cells potentially through increased PKA-dependent ROS production.

The dynamic average consensus problem for a group of agents is considered. Each agent is supposed to estimate the average of inputs applied to all agents in a distributed manner. A new structure for the distributed average estimator which can embed the internal model of inputs is proposed. Constructive design procedures are also given for the cases with constant inputs and time-varying inputs. The proposed estimator is validated via numerical simulations.

The expanded graphite intercalated compound (xGIC)/pressure sensitive adhesives (PSAs) were prepared by syrup process and in situ process. The effects of xGIC filler on the morphology and property of acrylic resin based UV-crosslinked PSA were investigated. The xGICs showed more uniform dispersion in acrylic matrix and the degree of filler connection was more prominent in the syrup process than in situ process. The peel strength and tackiness of UV-crosslinked PSAs were strongly dependent on the amount of the filler and the peel strength decreased with increasing xGIC. The thermal conductivity of PSAs was explained in terms of filler dispersion, wetting, and matrix infiltration. The thermal conductivity of PSA was 0.46 W/mK by adding 20 wt% of xGIC, which was 287% improvement compared to the unfilled PSA. It is speculated that 2-dimensional xGIC fillers effectively formed the thermal pathway. Open image in new window

Objectives : Neuroinflammation is characterized by microglial activation and the expression of major inflammatory mediators. The present study investigated the inhi bitory effect of ginsenoside Rg1 (GRg 1), a principle active ingredient in Panax ginseng, on pro-inflammatory cytokines and microglial activation induced by systemic lipopolysaccharide (LPS) treatment in the mouse brain tissue. Methods : Varying doses of GRg1 was orally administered (10, 20, and 30 mg/kg) 1 h before the LPS injection (3 mg/kg, intraperitoneally). The mRNA expression of pro-inflammatory cytokines in the brain tissue was measured using the quantitative real-time PCR method at 4 h aft er the LPS injection, Microglial activation was evaluated using western blotting and immunohistochemistry again st ionized calcium binding adaptor molecule 1 (Iba1) in the brain tissue. Cyclooxigenase-2 (COX-2) expressions also observed using western blotting and immunohistochemistry at 4 h after the LPS injection, In addition, double-immunofluorescent labeling of tumor necrosis factor-α (TNF-α) and COX-2 with microglia and neurons was processed in the brain tissue. Results : GRg 1 (30 mg/kg) significantly attenuated the upregulation of TNF-α , interleukin (IL)-1β and IL-6 mRNA in the brain tissue at 4 h after LPS injection. Morphologi cal activation and Iba1 protein expression of microglia induced by systemic LPS injection were reduced by the GRg1 (30 mg/kg) treatment. Upregulation of COX-2 protein expression in the brain tissue was also attenuated by the GRg1 (30 mg/kg) treatment. Conclusion : The results suggest that GRg1 is effective in the early stage of neuroinflammation which causes neurodegenerative diseases.

Solution processed hybrid silver nanowire (AgNW)-graphene nanoplatelets (GNP) films were prepared and the electrocatalytic activity for the cobalt redox electrolyte in dye-sensitized solar cells (DSSCs) was examined. Cyclic voltammograms and Tafel polarization measurements confirmed the superior electrocatalytic activity of AgNW-GNP electrode than that of standard Pt counter electrode (CE). Electrochemical impedance spectroscopic (EIS) study also revealed the lower charge transfer resistance (Rct) of AgNW-GNP compared to Pt based CE. However, the resistance of the electrolyte diffusion was higher for the AgNW-GNP based CE resulted from the porous structure of the hybrid CE. The photoconversion efficiencies of the DSSC prepared with AgNW-GNP based CE was found to be 2.44%, which was comparable to that of Pt based DSSC, 2.55%. This study proposed an alternative low-cost cathode material for the cobalt redox mediator based DSSCs.

The nutrients and antioxidative activities of fruits and leaves from Metasequoia glyptostroboides were investigated to provide basic data for the future development of functional foods. The nitrogen-free extract contents of fruit and leaves were 69.04% and 50.47%, respectively. Total phenolic content was higher in leaves (21.75 mg/GAE g) compared to the fruit (19.95 mg/GAE g). The mineral components of fruit and leaves mainly consisted of calcium (2,136.08 and 304.85 mg/100 g, respectively), potassium (1,355.53 and 1,144.04 mg/100 g, respectively), and phosphorous (426.30 and 350.50 mg/100 g, respectively). In terms of amino acid composition, aspartic acid, glutamic acid, proline, and leucine were relatively high, but methionine and cystine were low. The hot water extract from leaves was a more potent free radical-scavenger and had higher reducing activities than extracts from fruit. Thus, phenolics of M. glyptostroboides leaves can be utilized as an effective functional food substance for its natural antioxidant properties.

The Percutaneous Coronary intervention is a typical way of testing which could be performance to treat a stenosed region by inserting a stent using catheter. In this case, choosing the best stent amongst various kinds of stent for performing an intervention is the most difficult process. For the reason, a width of the blood vessel which is stenosed must be correctly measured to help an operator choose right size of stent. So based on pixel, a width of the blood vessel measured by using the way of Euclidean distance after designing a center-line of vessel from a certain point assigned by operator is shown as a profile in this study. This study would be used as a goof reference for operators when choosing right size of stent.

Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 139-743, KoreaReceived May 17, 2012, Accepted June 2, 2012Key Words : Human tyrosinase, Deletion mutants, Biochemical properties, Expression in Escherichia coliTyrosinase (monophenol, dihydroxyphenylalanine: oxygenoxidoreductase, EC 1.14.18.1) is an essential enzyme in thebiosynthesis of melanin pigment, which has a protectiveeffect against injurious ultraviolet radiation.

The photoplethysmography (PPG) signal measured from a mobile healthcare device contains various motion artifacts occurring from a patient’s movements. Recently, to reject the motion artifacts, the method of using an acceleration sensor was suggested, but such sensors are very expensive. Therefore, this study deals with a novel sensor device to replace the acceleration sensor, and evaluated the performance of the proposed sensor experimentally. In the results of the experiments, it is shown that the proposed sensor device can reconstruct the PPG signal despite the occurrence of motion artifacts, and also that the variation rate in heart rate analysis was 1.22%. According to the experimental results, the proposed method can be applied to design a low-cost device.

Coronary Intervention treatment has become the core that is the test of cardiac catheterization to conduct treatment with Coronary Arteriography. Operators must be careful in Coronary Intervention treatment because the stent is inserted into the point of narrowing of blood vessel. So, the operator must correctly recognize the path of blood vessel to deal with the problems which are damages and ruptures of blood vessel, and there would be some errors of finding the path of blood vessel by bad qualify of the image. Therefore in this paper, median filtering is conducted by preprocessing to evaluate the performance of the effect of noise of the image that affects quality of the image and Fuzzy Edge Extraction Techniques is tested by using Soble Edge Extraction Techniques to compare the performance with The Fuzzy Edge Extraction Techniques. In result, the performance, removing the noise and extracting the signal of Fuzzy Edge Extraction Techniques using median filtering, demonstrates the superiority.

Coronary angioplasty and coronary artery bypass graft, both are for the treatment of myocardial infarction widely used methods. For these procedures, there are especially difficulties in stenosis of blood vessels to diagnose accurately. To remedy this problem, by several researchers by using edge detection to detect stenosis of blood vessels has been studying. However, the results of using these methods vary defend on the vascular structure and the quality of the image. In this study, to improve these problems, the new algorithm is proposed. The proposed algorithm consists of methods to detect bifurcation of blood vessels and its ending point by using multi sampling, threshold and fuzzy algorithm. To evaluate the performance of the proposed algorithm, angiography was used for the different results of the blood vessels of the proposed algorithm, and the result was effective in detecting bifurcation of blood vessels and its ending point.