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Background: Although various methods are already used to calculate predicted postoperative forced expiratory volume in 1 second (FEV₁) based on preoperative FEV₁ in lung surgery, the predicted postoperative FEV₁ is not always the same as the actual postoperative FEV₁. Observed postoperative FEV₁ values are usually the same or higher than the predicted postoperative FEV₁. To overcome this issue, we investigated the relationship between the number of resected lung segments and the discordance of preoperative and postoperative FEV₁ values. Methods: From September 2014 to May 2020, the data of all patients who underwent anatomical lung resection by video-assisted thoracoscopic surgery (VATS) were gathered and analyzed retrospectively. We investigated the association between the number of resected segments and the differential FEV₁ (a measure of the discrepancy between the predicted and observed postoperative FEV₁) using the t-test and linear regression. Results: Information on 238 patients who underwent VATS anatomical lung resection at Kyung Hee University Hospital at Gangdong and by DH. Kim for benign and malignant disease was collected. After applying the exclusion criteria, 114 patients were included in the final analysis. In the multiple linear regression model, the number of resected segments showed a positive correlation with the differential FEV₁ (Pearson r=0.384, p

Diaphragmatic hernias have been reported in 0.8%–1.6% of patients who experience blunt chest trauma. The hernia is assumed to form as a result of direct diaphragmatic violation or significant intraabdominal or intrathoracic pressure caused by the trauma. Some reports have described cases of delayed diaphragmatic hernia and subsequent stomach perforation that occurred a few days to several years after an accident. We report an extremely rare case of diaphragmatic herniation in which the process from initial blunt trauma to visceral organ perforation took only 2 days, without any evidence of herniation on the initial X-ray or computed tomography. Delayed diaphragmatic herniation and subsequent visceral organ perforation should not be missed during the period immediately after blunt chest trauma.

Aortobronchial fistula (ABF) induced by an infected pseudoaneurysm of the thoracic aorta is a life-threatening condition. As surgical treatment is associated with significant mortality and morbidity, thoracic endovascular aneurysm repair (TEVAR) may be an alternative for the treatment of ABF. However, the long-term durability of this intervention is largely unknown and the recurrence of ABF is a potential complication. We experienced a case of recurrent ABF after stent grafting as an early procedure for an infected pseudoaneurysm of the thoracic aorta. Remnant ABF, bronchial and/or aortic wall erosion, vasa vasorum connected with ABF, and recurrent local inflammation of the thin aortic wall around ABF might cause recurrent hemoptysis. As a result, we suggest that TEVAR should be considered as a bridge therapy for the initial treatment of ABF resulting from an infected pseudoaneurysm, and that several options, such as second-stage surgery, should be considered to prevent the recurrence of ABF.

Background: Although classical multi-port video-assisted thoracic surgery has been widely performed, single-incision thoracoscopic surgery (SITS) is a popular surgical technique for the treatment of primary spontaneous pneumothorax (PSP). However, the inconvenient alignment of instruments and the limited field of view occasionally make surgeons convert from SITS to multi-port surgery or extend the incision. This study aimed to present an easy and safe SITS technique for PSP using a spinal needle. Methods: In total, 139 patients underwent SITS between May 2011 and December 2017. We used a spinal needle to hook the bulla or bleb, and wedge resection was performed through a small incision. Patients’ medical records were reviewed retrospectively, and a telephone survey was conducted to investigate the recurrence rate. Results: The mean age of the 139 patients was 23.62±9.60 years. The mean operative time was 36.69±14.64 minutes, and multi-port conversion was not performed. The mean postoperative hospital stay was 3.00±0.78 days, and the mean indwelling chest tube duration was 1.97±0.77 days. No complications were observed. In the mean follow-up period of 86.75±23.20 months, recurrence of pneumothorax was found in 3 patients. Conclusion: We suggest that SITS for PSP with the aid of a spinal needle to replace a grasper is a safe and easy technique that only requires a small incision.

l-Ascorbic acid (vitamin C, AA) is known as an antioxidant, but at high concentrations, AA can kill cancer cells through a prooxidant property. Sodium-dependent vitamin C transporter family-2 (SVCT-2) determines the cellular uptake of AA, and the activity of SVCT-2 is directly related to the anticancer activity of AA. Cancer cells that showed high SVCT-2 expression levels were more sensitive to AA treatment than cancer cells with low SVCT-2 expression levels. Cells with low SVCT-2 expression showed a hormetic response to a low dose of AA. Magnesium ions, which are known to activate SVCT-2, could increase the Vmax value of SVCT-2, so we investigated whether providing magnesium supplements to cancer cells with low SVCT-2 expression that had shown a hormetic response to AA would elevate the Vmax value of SVCT-2, allowing more AA to accumulate. To evaluate the effects of magnesium on cancer cells, MgSO4 and MgCl2 were screened as magnesium supplements; both forms showed synergistic anticancer effects with AA. Taken together, the results of this study suggest that magnesium supplementation enhanced the anticancer effect of AA by inhibiting the hormetic response at a low dose. This study has also demonstrated that AA treatment with magnesium supplementation provided more effective anticancer therapy than AA treatment alone.

The hybrid finite‐discrete element method (FDEM) is widely used for engineering applications, which, however, is computationally expensive and needs further development, especially when rock fracture process is modeled. This study aims to further develop a sequential hybrid FDEM code formerly proposed by the authors and parallelize it using compute unified device architecture (CUDA) C/C++ on the basis of a general‐purpose graphics processing unit (GPGPU) for rock engineering applications. Because the contact detection algorithm in the sequential code is not suitable for GPGPU parallelization, a different contact detection algorithm is implemented in the GPGPU‐parallelized hybrid FDEM. Moreover, a number of new features are implemented in the hybrid FDEM code, including the local damping technique for efficient geostatic stress analysis, contact damping, contact friction, and the absorbing boundary. Then, a number of simulations with both quasi‐static and dynamic loading conditions are conducted using the GPGPU‐parallelized hybrid FDEM, and the obtained results are compared both quantitatively and qualitatively with those from either theoretical analysis or the literature to calibrate the implementations. Finally, the speed‐up performance of the hybrid FDEM is discussed in terms of its performance on various GPGPU accelerators and a comparison with the sequential code, which reveals that the GPGPU‐parallelized hybrid FDEM can run more than 128 times faster than the sequential code if it is run on appropriate GPGPU accelerators, such as the Quadro GP100. It is concluded that the GPGPU‐parallelized hybrid FDEM developed in this study is a valuable and powerful numerical tool for rock engineering applications.

Mechanical breakage systems are generally employed to demolish a portion of a concrete building, however it is time consuming and costly. And the mechanical demolition work involves various risks such as those associated with occupational safety and presents a noise hazard to the general public living in the vicinity. Therefore, alternative methods for such work have been sought. For this purpose, a dynamic breakage system utilizing diamond-shaped charge holders was proposed to rapidly remove the desired portion of the concrete foundation. The charge holders which initiate crack growth were placed inside a concrete mass along the desired fracture plane. In this study, full-scale blast experiments utilizing the charge holders were introduced and the roughness of fracture planes was observed using a 3-dimensional photography system. In order to verify the effect of the charge holders on fracture controlling in full-scale blast experiments, the fracture processes of the concrete blocks were analyzed using the dynamic fracture process analysis (DFPA) code. The mechanism required to achieve controlled breakage was discussed after taking into account the influence of various loading conditions and crack tip velocity. It was found that the DFPA tool is a useful instrument in the analysis of full scale blast experiments.

Sweet potato leaf curl virus (SPLCV) causes yield losses in sweet potato cultivation. Diagnostic techniques such as serological detection have been developed because these plant viruses are difficult to treat. Serological assays have been used extensively with recombinant antibodies such as whole immunoglobulin or single-chain variable fragments (scFv). An scFv consists of variable heavy (VH) and variable light (VL) chains joined with a short, flexible peptide linker. An scFv can serve as a diagnostic application using various combinations of variable chains. Two SPLCV-specific scFv clones, F7 and G7, were screened by bio-panning process with a yeast cell which expressed coat protein (CP) of SPLCV. The scFv genes were subcloned and expressed in Escherichia coli. The binding affinity and characteristics of the expressed proteins were confirmed by enzyme-linked immunosorbent assay using SPLCV-infected plant leaves. Virus-specific scFv selection by a combination of yeast-surface display and scFv-phage display can be applied to detection of any virus.

Although surgery and radiation are beneficial for treating cancer, they can also lead to malfunctions of the lymphatic system such as secondary lymphedema. This abnormality of the lymphatic system is characterized by severe swelling, adipogenesis, inflammation, and fibrosis in the lymphedematous region. Moreover, the proliferation of fibrotic tissue in the lymphedematous region generates edema that is no longer spontaneously reversible. No treatment for fibrosis has been validated in patients with lymphedema. In our efforts to develop a therapeutic agent for lymphedema fibrosis, we used a newly established mouse hind limb model. Previous studies have demonstrated that hyaluronic acid accumulates in the lymphedematous region. Thus, we challenged mice with of hyaluronidase (HYAL), with the aim of reducing fibrogenesis. After subcutaneous injections in the lymphedematous mouse leg every two days, the volume of lymphedema had reduced significantly by 7 days post-operation. Histochemical analysis indicated that collagen accumulation and myofibroblast differentiation were decreased in epidermal tissues after HYAL injection. Moreover, it was associated with upregulation of interferon-gamma, increased numbers of Th1 cells, and downregulation of interleukin-4 and interleukin-6 in the lymphedematous region and spleen. These results indicate that hydrolysis of hyaluronic acid can boost an anti-fibrotic immune response in the mouse lymphedema model.

3D8 scFv, a catalytic recombinant antibody developed in the MRL mouse, exhibits nucleic acid-hydrolyzing activity. Previous studies have demonstrated that tobacco plants harboring 3D8 scFv antibodies showed broad-spectrum resistance to infection by both DNA and RNA viruses. In this study, potatoes were transformed with the 3D8 scFv gene and screened by potato virus X (PVX) challenge. Starting with the T0 and T1 potato lines, PVX-tolerant T1 potatoes were identified in the field and characterized by ELISA and RT-PCR analysis. T2 potatoes were propagated for T3 generation and additional virus challenges in the field, and 44% of the 3D8 scFv T3 transgenic potatoes grown in GMO fields were found to be tolerant to PVX infection. Tubers from PVX-tolerant T3 lines were 60% bigger and 24% heavier, compared with tubers from PVX-susceptible transgenic lines and wild-type potatoes. Three-step virus challenge experiments and molecular characterization techniques were used for plants grown in growth chambers or fields to identify 3D8 scFv-transgenic, PVX-tolerant potatoes. These studies also revealed that the viral tolerance enabled by 3D8 scFv persisted during asexual propagation.

The original valve-sparing procedures for aortic root aneurysms were remodeling and reimplantation of the aortic root. The remodeling technique provides more physiologic movement of the cusps within 3 reconstructed neo-sinuses, thus preserving root expansibility through the interleaflet triangles. However, the durability of remodeling has been a matter of concern due to the high rate of aortic insufficiency when annular dilation is not addressed. Therefore, a modified approach was developed, combining a physiologic remodeling of the root with a subvalvular annuloplasty. This case report highlights the first case of successful aortic root remodeling with external subvalvular ring annuloplasty in Korea.

High-voltage pulse technology has been applied to rock excavation, liberation of microfossils, drilling of rocks, oil and water stimulation, cleaning castings, and recycling products like concrete and electrical appliances. In the field of rock mechanics, research interest has focused on the use of high-voltage pulse technology for drilling and cutting rocks over the past several decades. In the use of high-voltage pulse technology for drilling and cutting rocks, it is important to understand the fragmentation mechanism in rocks subjected to high-voltage discharge pulses to improve the effectiveness of drilling and cutting technologies. The process of drilling rocks using high-voltage discharge is employed because it generates electrical breakdown inside the rocks between the anode and cathode. In this study, seven rock types and a cement paste were electrically fractured using high-voltage pulse discharge to investigate their dielectric breakdown properties. The dielectric breakdown strengths of the samples were compared with their physical and mechanical properties. The samples with dielectric fractured were scanned using a high-resolution X-ray computed tomography system to observe the fracture formation associated with mineral constituents. The fracture patterns of the rock samples were analyzed using numerical simulation for high-voltage pulse-induced fragmentation that adopts the surface traction and internal body force conditions.

Conventional induction furnaces have been in operation in nonferrous metal and related industries with poor energy efficiencies of only 50-60%. Moreover, the efficiency of atmosphere furnace, one of the various heating facilities for metal billets, is about 20%. For ensuring high energy efficiency in these heating furnaces fields, as one of the better counterplans, a novel dc induction heating method using HTS magnets has been suggested. To realize the HTS dc induction furnace (HIF) in the industrial field, the most important issue is to guarantee economic favor in comparison with two different types of conventional furnaces. In this paper, we performed an economic feasibility study of an HIF in terms of electricity fee minimization. Net present value, internal rate of return, and pay-back period methods were used to evaluate the investment returns of an HIF. All indicators related to direct benefits were calculated and analyzed for finding economic feasibility. The analysis results will be applied to decision making process for the commercialization of the HIF.

A three-dimensional combined finite-discrete element element method (FDEM), parallelized by a general-purpose graphic-processing-unit (GPGPU), was applied to identify the fracture process of rough concrete&ndash, rock joints under direct shearing. The development process of shear resistance under the complex interaction between the rough concrete&ndash, rock joint surfaces, i.e., asperity dilatation, sliding, and degradation, was numerically simulated in terms of various asperity roughness under constant normal confinement. It was found that joint roughness significantly affects the development of overall joint shear resistance. The main mechanism for the joint shear resistance was identified as asperity sliding in the case of smoother joint roughness and asperity degradation in the case of rougher joint asperity. Moreover, it was established that the bulk internal friction angle increased with asperity angle increments in the Mohr&ndash, Coulomb criterion, and these results follow Patton&rsquo, s theoretical model. Finally, the friction coefficient in FDEM appears to be an important parameter for simulating the direct shear test because the friction coefficient affects the bulk shear strength as well as the bulk internal friction angle. In addition, the friction coefficient of the rock&ndash, concrete joints contributes to the variation of the internal friction angle at the smooth joint than the rough joint.

The external wall insulation method was introduced to enhance the energy efficiency of existing buildings. It does not cause a decrease of inner space and costs less in comparison to methods that insert insulation panels inside walls. However, it has been reported that external wall insulation boards are disconnecting from walls due to malfunctions of the adhesive. This causes not only repair costs, but also serious injury to pedestrians. Separation problems occur when the bonded positions are incorrect and/or the total area and thickness of the adhesive is smaller than the required amount. A challenge is that these faults can hardly be inspected after installing boards. For this reason, a real-time inspection system is necessary to detect potential failure during adhesive works. Position, area and thickness are major aspects to inspect, and thus a method to process image data of these seems efficient. This paper presents a real-time quality inspection system introducing image processing technology to detect potential errors during adhesive works of external wall insulation, and it is predicted to contribute to achieving sustainable remodeling construction by reducing squandered material and labor costs. The system consists of a graphic data creation module to capture the results of adhesive works and a quality inspection module to judge the pass or fail of works according to an algorithm. A prototype is developed and validated against 100 panels with 800 adhesive points.

L-Ascorbic acid (vitamin C, AA) exhibits anti-cancer effects with high-dose treatment through the generation of reactive oxygen species (ROS) and selective damage to cancer cells. The anti-cancer effects of L-ascorbic acid are determined by sodium-dependent vitamin C transporter 2 (SVCT-2), a transporter of L-ascorbic acid. In this study, we demonstrate that L-ascorbic acid treatment showed efficient anti-cancer activity in cell lines with high expression levels of SVCT-2 for a gradient concentration of L-ascorbic acid from 10 μM −2 mM. However, in low SVCT-2 expressing cell lines, high-dose L-ascorbic acid (>1 mM) showed anti-cancer effects but low-dose (L-ascorbic acid was also observed in high SVCT-2 expressing cell lines in the presence of a SVCT family inhibitor. Insufficient uptake of L-ascorbic acid in low SVCT-2 expressing cancer cell lines cannot generate sufficient ROS to kill cancer cells, resulting in the hormetic response. Molecular analysis confirmed the increased expression of cancer proliferation markers in the hormetic dose response. These results suggest that L-ascorbic exhibits a biphasic effect in cancer cells depending on SVCT-2 expression.

Ethnopharmacological relevance Phyllanthus acidus (L.) Skeels (Phyllanthaceae) has traditionally been used to treat gastric trouble, rheumatism, bronchitis, asthma, respiratory disorders, and hepatitis. Despite this widespread use, the pharmacological activities of this plant and their molecular mechanisms are poorly understood. Therefore, we evaluated the immunopharmacological activities of the methanolic extract of the aerial parts of this plant (Pa-ME) and validated its pharmacological targets. Materials and methods Lipopolysaccharide (LPS)-treated macrophages, an HCl/EtOH-induced gastritis model, and an acetic acid-injected capillary permeability mouse model were employed to evaluate the anti-inflammatory activity of Pa-ME. Potentially active anti-inflammatory components of this extract were identified by HPLC. The molecular mechanisms of the anti-inflammatory activity were studied by kinase assays, reporter gene assays, immunoprecipitation analysis, and overexpression of target enzymes. Results Pa-ME suppressed the production of nitric oxide (NO) and prostaglandin E 2 (PGE 2 ) and prevented morphological changes in LPS-treated RAW264.7 cells. Moreover, both HCl/EtOH-induced gastric damage and acetic acid-triggered vascular permeability were restored by orally administered Pa-ME. Furthermore, this extract downregulated the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 and reduced the nuclear levels of NF-κB. Signalling events upstream of NF-κB translocation, such as phosphorylation of Src and Syk and formation of Src/Syk signalling complexes, were also inhibited by Pa-ME. The enzymatic activities of Src and Syk were also suppressed by Pa-ME. Moreover, Src-induced and Syk-induced luciferase activity and p85/Akt phosphorylation were also inhibited by Pa-ME. Of the identified flavonoids, kaempferol and quercetin were revealed as partially active anti-inflammatory components in Pa-ME. Conclusion Pa-ME exerts anti-inflammatory activity in vitro and in vivo by suppressing Src, Syk, and their downstream transcription factor, NF-κB.

Rock bolts are used as permanent and temporary support systems in tunneling and mining operations. A dynamic-expansion rock bolt system that can be installed rapidly in a drilled hole is introduced in this article. The dynamic-expansion rock bolt system consists of a star-shaped steel tube and an ignition system with a dynamic expansion agent in the steel tube of the rock bolt. After the ignition of the dynamic agent in the tube, the star-shaped steel tube expands dynamically as a result of gas production by the dynamic agent. This expansion leads to frictional mounting of the tube in a drilled hole. Laboratory-scale pull-out tests of the rock bolt, installed in a thick steel tube, were performed to investigate the friction behavior between the steel tube and the smooth wall of a drilled hole. These tests revealed that the ultimate pull-out load reached approximately 6 kN and that a long displacement subsequently occurred. Field-scale tests for two prototype rock bolts were performed to evaluate the pull-...

In 2013, Tomato chlorosis virus (ToCV) was identified in symptomatic tomato plants in Korea. In the present study, a loop-mediated isothermal amplification (LAMP) method was developed using four specific primers designed against ORF6 in ToCV RNA2 to detect ToCV rapidly and with high sensitivity. The optimized reaction involved incubation of a reaction mixture containing 2U Bst DNA polymerase and 4mM MgSO4 for 1h at 60-62 °C. Although specific and rapid detection of ToCV by LAMP was confirmed, false-positive reactions caused by carry-over contamination sometimes occurred because of the high sensitivity of LAMP compared with other detection methods. To prevent false-positive reactions, dUTP was substituted for dTTP and uracil-DNA glycosylase (UDG) was added to the LAMP reaction. First, the LAMP reaction was conducted successfully with substitution of dUTP for dTTP. Before the next reaction, LAMP products with incorporated dUTP were cleaved selectively by UDG without any effect on thymine-containing DNA (template DNA). This modified LAMP method complemented with UDG treatment to prevent carry-over contamination offers a potentially powerful method for detecting plant viruses.

L-Ascorbic acid (vitamin C, AA) exhibits anti-cancer effects with high-dose treatment through the generation of reactive oxygen species (ROS) and selective damage to cancer cells. The anti-cancer effects of L-ascorbic acid are determined by sodium-dependent vitamin C transporter 2 (SVCT-2), a transporter of L-ascorbic acid. In this study, we demonstrate that L-ascorbic acid treatment showed efficient anti-cancer activity in cell lines with high expression levels of SVCT-2 for a gradient concentration of L-ascorbic acid from 10 μM −2 mM. However, in low SVCT-2 expressing cell lines, high-dose L-ascorbic acid (>1 mM) showed anti-cancer effects but low-dose (

A water tube with detonating cord was devised to control the blast dust. Water diffusion experiments with different detonating cord positions were conducted during the series of experiments to optimize the design parameters of the tube. Images from high speed camera were analyzed to evaluate the results. AUTODYN program was adopted to simulate the diffusion process of water and compared with the images. Diffusion of water shows cross flow in case of external charge while the internal case shows radial flow. A bubble ring was formed during the numerical analysis of internal charge case as occurred in underwater blast. An additional bubble ring was formed by the reflection pressure from the ground. And the Weber number was determined as sufficient for spray atomization performance of the water tube.

Red seabream iridovirus (RSIV), a member of the Iridoviridae family, is the causative pathogen of some of the most explosive epidemics of emerging viral diseases in many Asian countries, leading to huge economic losses in aquaculture. Rapid molecular detection for surveillance or diagnosis has been a critical component in reducing the prevalence of RSIV infection. In the present study, a novel and highly specific loop-mediated isothermal amplification (LAMP) assay for the sensitive and rapid detection of RSIV infection in fishes was developed. Using a set of synthesized primers matching a specific region of the RSIV genome (GenBank accession no.: AB666336.1), the efficiency and specificity of the LAMP assay were optimized in terms of the reaction temperature and DNA polymerase concentration, as they are the main determinants of the sensitivity and specificity of the LAMP assay. In particular, we demonstrated that our assay could be applied to efficiently detect RSIV infection in red sea bream. Our results provide a simple and convenient method for the detection of viral infection in aquatic organisms. Key words: Red sea bream, Iridovirus, polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP).

Cold agglutinins are predominately immunoglobulin M autoantibodies that react at cold temperatures with surface antigens on the red blood cell. This can lead to hemagglutination at low temperatures, followed by complement fixation and subsequent hemolysis on rewarming. Development of hemagglutination or hemolysis in patients with cold agglutinins is a risk of cardiac surgery under hypothermia. In addition, there is the potential for intracoronary hemagglutination with inadequate distribution of cardioplegic solutions, thrombosis, embolism, ischemia, or infarction. We report a patient with incidentally detected cold agglutinin who underwent normothermic cardiac surgery with warm blood cardioplegia.

Electrical disintegration is an effective liberation technique in mineral processing where the liberation ratio depends on the mineralogical properties of the mineral grains. However elucidation of the liberation behavior is difficult since the fragments after the electrical disintegration are fine and complex. This study applies electrical disintegration to cement paste samples with various dispersed mineral particles (calcite, quartz, albite, and pyrite) and the disintegrated products are observed with a micro-focus X-ray CT scanner. Current channels and crack extension behavior from the channels are identified by cross sectional CT and three dimensional reconstructed images. A classification of the crack patterns was carried out and compared with the results of liberation ratio measurements of the products.

Granite is a significantly anisotropic rock that is affected by the pre-existing microcrack distribution. In rock engineering applications in a variety of fields, it is crucial to understand the influence of the internal microcrack distribution on the mechanical properties of the rock. In this paper, static and dynamic fracture toughness tests were conducted with straight notched disc bend (SNDB) specimens of Youngju granite to investigate the relationship between the microcrack-induced fracture toughness anisotropy and the loading rate dependency. Three groups of specimens were manufactured with three different orthogonal directions, which were determined by the P-wave velocity measurement. In order to conduct the static and dynamic fracture toughness tests, a servo-controlled Material Testing System (MTS) machine and a split Hopkinson pressure bar (SHPB) apparatus were respectively used. In the dynamic test, to achieve the stress equilibrium state in the measurement, a careful pulse shaping technique with a copper and rubber pulse shaper was used. The results of the entire range of tests in this study revealed that the fracture toughness of Youngju granite has a clear loading rate dependency. Further, we found that the preferred orientation of pre-existing microcracks causing strong anisotropy of fracture toughness under static loading rates became significantly weaker in the dynamic loading state. Finally, a possible reason for this relationship between the fracture toughness anisotropy and the loading rate dependency is discussed with different fracturing processes of rock under the static and the dynamic loading states using image analysis for generated cracks.

Rapid and sensitive detection methods for three species of Curtovirus were developed using a loop-mediated isothermal amplification (LAMP) technique. A universal primer set for detecting the three main species of Curtovirus at the same time, and three kinds of species-specific primer sets were designed and used for LAMP reactions. Results from the LAMP reactions were visualized both by color changes after adding SYBR Green I staining dye and by DNA laddering on agarose gel electrophoresis. The optimal conditions for the curtovirus LAMP reaction were confirmed at 60°C for the universal primers and at 62°C for the three species-specific primer sets. Amplification of curtoviruses by LAMP reaction was ten-fold more sensitive than that by polymerase chain reaction. Primers designed for curtovirus detection in this study did not anneal to or amplify DNA from other DNA or RNA viruses (tomato yellow leaf curl virus, tomato spotted wilt virus, and potato virus Y). Taken together, the primer sets and reaction conditions developed in this study show that the LAMP technique could be a useful tool to detect the three species of Curtovirus simultaneously and distinguish them in the laboratory and the field.

Oxidant-mediated death of lung epithelial cells due to cigarette smoking plays an important role in pathogenesis in lung diseases such as idiopathic pulmonary fibrosis (IPF). However, the exact mechanism by which oxidants induce epithelial cell death is not fully understood. Reactive oxygen species (ROS) modulator 1 (Romo1) is localized in the mitochondria and mediates mitochondrial ROS production through complex III of the mitochondrial electron transport chain. Here, we show that Romo1 mediates mitochondrial ROS production and apoptosis induced by oxidative stress in lung epithelial cells. Hydrogen peroxide (H2O2) treatment increased Romo1 expression, and Romo1 knockdown suppressed the cellular ROS levels and cell death triggered by H2O2 treatment. In immunohistochemical staining of lung tissues from patients with IPF, Romo1 was mainly localized in hyperplastic alveolar and bronchial epithelial cells. Romo1 overexpression was detected in 14 of 18 patients with IPF. TUNEL-positive alveolar epithelial cells were also detected in most patients with IPF but not in normal controls. These findings suggest that Romo1 mediates apoptosis induced by oxidative stress in lung epithelial cells.

In this paper, the phase-shift full-bridge DC/DC converter with fixed-phase operation inverter is proposed. The proposed circuit consists of two full-bridge inverters which are connected in parallel. While one full-bridge inverter operates as the fixed-phase, it regulates the output voltage by adjusting the phase of the other inverter. During the normal operation period, the proposed circuit makes the less amount of conduction loss of the primary switches and secondary synchronous rectifiers, as well as the less amount of the current ripple of the output inductor, than the conventional phase-shift full-bridge DC/DC converter does. Also, it achieves high efficiency by reducing the snubber loss of the secondary synchronous rectifier. To sum up, the present inquiry analyzes the theoretical characteristics of the proposed circuit, and shows the experimental results from a prototype for 450W power supply.

The percussion rate and spacing of the button of drill bit are very important in maximizing the drilling efficiency. Therefore, a series of percussion tests using Hopkinson bar system was carried out to assess the fragmentation performance against the beat rate and spacing of a drill bit. First, single percussion test complemented with numerical simulation was performed to analyze rock fragmentation phenomenon and to describe the fragmentation process. Next, multiple percussion test that repetitively strike the rock sample moving at predetermined rate was carried out to predict drilling efficiency against the button spacing. After the tests, the fragmented volume of the rock was measured by laser scanner and the drilling performance was analyzed using the calculated percussive energy and measured negative volume. Based on the results, the single impact performance of drill bit with 102 mm diameter was predicted.

Transforming growth factor-β1 (TGF-β1) is a key cytokine that plays a critical role in idiopathic pulmonary fibrosis (IPF). The genotypes of T869C polymorphism may be associated with the susceptibility to fibrotic lung disease. We investigated a single-nucleotide polymorphism at exon 1 nucleotide position 29 (T → C) of the TGF-β1 gene. Eighty-five healthy controls and 85 subjects with surgically confirmed IPF were investigated using polymerase chain reaction and restriction enzyme fragment length polymorphism techniques. The IPF patients consisted of 55 men and 30 women. The mean age was 61 ± 8 years. Fifty-one (60 %) of the 85 IPF patients were smokers and 34 were nonsmokers. The distribution of genotypes between IPF patients and controls was significantly different (IPF: TT 43.5 % and TC or CC 56.5 %; controls: TT 27.1 % and TC or CC 72.9 %, p = 0.037). TT genotype was significantly associated with decreased PaO2 and increased D(A–a)O2 upon initial diagnosis (p = 0.006 and 0.009, respectively). There was a positive association between TT genotype and IPF development (odds ratio [OR] = 2.1, 95 % confidence interval [CI] = 1.1–4.0, p = 0.028). This study suggests that the TGF-β1 gene T869C polymorphism may affect susceptibility to IPF in Koreans. Larger studies are required to confirm the genetic association of TGF-β1 gene polymorphism and IPF.

Information on the deformation behavior and fracture strength of rocks subjected to dynamic loadings is important to stability analyses of underground openings underground vibration due to rock blasts, earthquakes and rock bursts. In this study, Split Hopkinson Pressure Bar (SHPB) system was applied to estimate dynamic compressive and tensile fracture strengths of limestone and also examine deformation behavior of limestones under dynamic loadings. A micro-focus X-ray CT scanner was used to observe non-destructively inside the impacted limestone specimens. From the dynamic tests, it was revealed that the limestone have over 140MPa dynamic compressive strength and the strain-rate dependency of the strength. Dynamic Brazilian tensile strength of the limestone exceeds 21MPa and shows over 3 times static Brazilian tensile strength.

In this paper, we implemented a HF-band magnetic-field communication system consisting of an amplitude shift keying(ASK) transmitter, a pair of loop antennas, and an ASK receiver. Especially, we suggested a new ASK transmitter architecture, where a drain bias of class E amplifier is switched alternatively between two voltage levels with respect to input data. A maximum 5 W class E amplifier was designed using a low cost IRF510 power MOSFET at the frequency of 6.78 MHz. A measured sensitivity of the designed ASK receiver is -78 dBm, which consists of a log amplifier, a filter, and a comparator. Maximum communication range of magnetic-wave communication system with loop antennas was calculated using magnetic field equations in both near-field and far-field ranges. Also, in order to verify the calculated values, an indoor propagation loss was measured using a pair of loop antennas whose dimensions are . Maximum operating range is estimated about 35 m in case of transmitter`s output power of 1 W and receiver sensitivity of -70 dBm, respectively. Finally, the communication field test using the designed ASK transmitter and receiver was successfully done at the distance of 5 m.

Magnesium is one of the light weight materials, which can improve fuel economy and reduce emissions in automotive industry. Recently, magnesium alloys have gained considerable attention due to good mechanical properties. In this work, we have performed an explosive welding using the magnesium alloys (AZ31) and stainless steel (SUS 304). As a result, SUS304/AZ31 were successfully combined each other; however, a resolidified interlayer was observed at the point of welded layer. To reduce the resolidified interlayer, we have changed the thickness (0.5 mm and 1 mm) of stainless steel, distance (45 mm and 60 mm) between explosive and the center of materials and initial angle (20° and 30°) of explosive. In the case of the thickness 0.5 mm and angle of 30°, the resolidfied interlayer was not observed due to the increase of distance from the explosive. To accurately estimate the resolidified interlayer, electron probe micro-analyzer (EPMA) method and hardness were used. For the EPMA analysis, mixed materials were confirmed at the resolidified interlayer, and the measurement exhibited the middle value compared with the AZ31 and SUS304.

ZnO-98% and Ga 2 O 3 -2% powder were consolidated by shock compaction technique, which uses a high performance explosive. The microstructural and electrical characteristics of ZnOGa 2 O 3 compact with density of 97% and hardness of 220~250 H v were investigated using SEM (Scanning Electron Microscope) and X-ray diffraction analysis, respectively. In the microstructures of the compact, there were no visible cracks at most of the surface areas, and interparticle bonding between powder particles was confirmed. The broadened peaks were detected due to deformation of crystallited size and high electric resistances were confirmed due to increased grains because of shock energy with a high pressure and high velocity. Key words Shock compaction, Shock pressure, Ceramics, Explosive, ZnO초 록 본 논문에서는 산업용 폭약을 이용한 충격고화기술을 ZnO-98%과 Ga 2 O 3 -2% 혼합분말에 적용하여 직경 30mm, 두께 6mm인 ZnOGa 2 O 3 고화체를 형성 시켰다. 고화체의 경도 및 상대밀도는 각각 220~250 Hv, 97%이었으며, 표면에 대한 주사현미경 관찰결과 균열 및 결함은 발생되지 않았으며, 분말입자들은 강한 충격파에 의해 변형되어 서로 결합되었음을 확인하였다. 또한 X-ray 분석결과로부터 입자 간의 격자결합 및 결정자의 변형을 확인 할 수 있었으며, 이러한 격자결합과 결정자의 변형은 높은 전기저항의 원인이 된다는 것을 보여주었다.핵심어 충격분말고화, 충격파, 세라믹, 폭약, ZnO