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Nanotransfer printing (nTP) is one of the most promising nanopatterning methods given that it can be used to produce nano-to-micro patterns effectively with functionalities for electronic device applications. However, the nTP process is hindered by several critical obstacles, such as sub-20 nm mold technology, reliable large-area replication, and uniform transfer-printing of functional materials. Here, for the first time, a dual nanopatterning process is demonstrated that creates periodic sub-20 nm structures on the eight-inch wafer by the transfer-printing of patterned ultra-thin (<50 nm) block copolymer (BCP) film onto desired substrates. This study shows how to transfer self-assembled BCP patterns from the Si mold onto rigid and/or flexible substrates through a nanopatterning method of thermally assisted nTP (T-nTP) and directed self-assembly (DSA) of Si-containing BCPs. In particular, the successful microscale patternization of well-ordered sub-20 nm SiOx patterns is systematically presented by controlling the self-assembly conditions of BCP and printing temperature. In addition, various complex pattern geometries of nano-in-micro structures are displayed over a large patterning area by T-nTP, such as angular line, wave line, ring, dot-in-hole, and dot-in-honeycomb structures. This advanced BCP-replicated nanopatterning technology is expected to be widely applicable to nanofabrication of nano-to-micro electronic devices with complex circuits. [ABSTRACT FROM AUTHOR]

The control of domain sizes provides a powerful means to engineer the characteristics of monolayer (ML) MoS2 films for specific applications including catalysts for hydrogen evolution and thin-film transistors. Here, we report an efficient way to control domain structures of MoS2 by substrate-dependent growth mode control. Deterministic control of growth modes, associated with catalytic intermediates, is introduced by utilizing different growth substrates in metal-organic chemical vapor deposition (MOCVD) of ML MoS2. Na-Mo-O eutectic alloys formed by a soda lime (SL) substrate dominate the growth based on a vapor-liquid-solid (VLS) process, resulting in large-crystalline domains of MoS2 with a reduced density of liquid nuclei. On the other hand, MoO3-x seeds formed from an alkali aluminosilicate (AA) substrate accelerate nucleation via a vapor-solid-solid (VSS) process for nanocrystalline domains. ML MoS2 of nanocrystalline domains resulted in efficient hydrogen evolution reactions (HERs), while large-domain films showed better electron conductivity. [ABSTRACT FROM AUTHOR]

Topological defects in matter behave collectively to form highly non-trivial structures called topological textures that are characterised by conserved quantities such as the winding number. Here we show that an epitaxial ferroelectric square nanoplate of bismuth ferrite subjected to a large strain gradient (as much as 105m−1) associated with misfit strain relaxation enables five discrete levels for the ferroelectric topological invariant of the entire system because of its peculiar radial quadrant domain texture and its inherent domain wall chirality. The total winding number of the topological texture can be configured from − 1 to 3 by selective non-local electric switching of the quadrant domains. By using angle-resolved piezoresponse force microscopy in conjunction with local winding number analysis, we directly identify the existence of vortices and anti-vortices, observe pair creation and annihilation and manipulate the net number of vortices. Our findings offer a useful concept for multi-level topological defect memory. [ABSTRACT FROM AUTHOR]

The PbTiO3/SrTiO3 superlattice thin films with a low volume fraction of PbTiO3 have not attracted much interest because they are thought to exhibit only a paraelectric state. In this study, we focus on a superlattice thin film with thin PbTiO3 (PTO) and thick SrTiO3 (STO) layers, wherein the hidden ferroelectricity in the thin PbTiO3 layer is revealed. Atomic scale imaging analysis and electron energy loss spectroscopy reveal the existence of a disordered ferroelectric polarization state without innate tetragonal distortion in the (6PTO/15STO)5 superlattice. The piezoelectric force microscopy analysis confirms that this disordered ferroelectricity can enhance piezoelectric response. [ABSTRACT FROM AUTHOR]

Objectives The definition of spontaneous pneumothorax is accumulation of air in the pleural space, resulting in dyspnea or chest pain. Unlike primary spontaneous pneumothorax, secondary pneumothorax can be a life-threatening condition and spontaneous healing rate is uncommon. Although surgery is the most effective treatment modality for pneumothorax, surgical management and timing is difficult where there is underlying lung disease and/or medical comorbidities. Prolonged air leakage increases the morbidity and mortality in thoracic surgery. We hypothesized that duration of air leakage before operation may lead to increase in complications. Methods This study is a retrospective review of 155 consecutive patients with air leakage who underwent bullectomy for secondary spontaneous pneumothorax from January 2005 to July 2013. The patients were divided according to the duration of preoperative air leakage. The patients were followed-up until the time of last visit or death. Postoperative morbidity and mortality were assessed and the risk factors for complications were analyzed. Results The median age was 65 years (range, 52-88) with male predominance (96.13%). The median duration of preoperative air leakage was 6 days (range, 1-30). The median surgery time was 90 minutes (range, 25-300) and median hospital stay after operation was 7 days (range, 3-75). Postoperative complications occurred in 38 patients (24.52%) and postoperative recurrence was shown to have occurred in 8 patients (5.16%). With multivariate analysis, risk factors for postoperative complications were: underlying interstitial lung disease and air leakage 5 days before operation. Conclusion Persistent air leakage was a major surgical indication for pneumothorax. Early surgical treatment reduced postoperative complications for secondary spontaneous pneumothorax. [ABSTRACT FROM AUTHOR]

Tungsten trioxide is a binary oxide that has potential applications in electrochromic windows, gas sensors, photo-catalysts, and superconductivity. Here, we analyze the crystal structure of atomically flat epitaxial layers on YAlO3 single crystal substrates and perform nanoscale investigations of the ferroelastic twins revealing a hierarchical structure at multiple length scales. We have found that the finest stripe ferroelastic twin walls along pseudocubic <100> axes are associated with cooperative mosaic rotations of the monoclinic films and the larger stripe domains along pseudocubic <110> axes are created to reduce the misfit strain through a commensurate matching of an effective in-plane lattice parameter between film and substrate. The typical widths of the two fine and larger stripe domains increase with film thickness following a power law with scaling exponents of ~0.6 and ~0.4, respectively. We have also found that the twin structure can be readily influenced by illumination with an electron beam or a tip-based mechanical compression. [ABSTRACT FROM AUTHOR]

A highly dense, 4 lm-thick Pb(Zr,Ti)O3 (PZT) film is deposited on amorphous magnetostrictive Metglas foil (FeBSi) by granule spray in vacuum process at room temperature, followed by its localized annealing with a continuous-wave 560 nm ytterbium fiber laser radiation. This longerwavelength laser radiation is able to anneal the whole of thick PZT film layer without any deteriorative effects, such as chemical reaction and/or atomic diffusion, at the interface and crystallization of amorphous Metglas substrate. Greatly enhanced dielectric and ferroelectric properties of the annealed PZT are attributed to its better crystallinity and grain growth induced by laser irradiation. As a result, a colossal off-resonance magnetoelectric (ME) voltage coefficient that is two orders of magnitude larger than previously reported output from PZT/Metglas film-composites is achieved. The present work addresses the problems involved in the fabrication of PZT/Metglas filmcomposites and opens up emerging possibilities in employing piezoelectric materials with low thermal budget substrates (suitable for integrated electronics) and designing laminate composites for ME based devices. [ABSTRACT FROM AUTHOR]

Reexpansion pulmonary edema is a rare but potentially life-threatening condition that occurs when a collapsed lung reexpands, usually in the same side of collapsed lung. We present a rare case in which a 57-year-old Korean man had a large amount of malignant pleural effusion. After undergoing tube thoracostomy drainage for the pleural effusion, a contralateral reexpansion pulmonary edema developed while the ipsilateral lung was half collapsed. The patient was dyspneic with an oxygen saturation that dropped to 66 %. After conservative treatment with oxygen therapy, steroid administration, and negative suction application (suction pressure of -20 cm H2O) in the right pleural cavity for five days, the right lung could be fully expanded without development of reexpansion pulmonary edema, and the reexpansion pulmonary edema in the left lung resolved. Although it is a very rare condition, it is important to know that contralateral occurrence of reexpansion pulmonary edema can occur, especially when the ipsilateral lung is collapsed. Being aware of this potential condition can allow for early and proper management. [ABSTRACT FROM AUTHOR]

Reexpansion pulmonary edema is a rare but potentially life-threatening condition that occurs when a collapsed lung reexpands, usually in the same side of collapsed lung. We present a rare case in which a 57-year-old Korean man had a large amount of malignant pleural effusion. After undergoing tube thoracostomy drainage for the pleural effusion, a contralateral reexpansion pulmonary edema developed while the ipsilateral lung was half collapsed. The patient was dyspneic with an oxygen saturation that dropped to 66 %. After conservative treatment with oxygen therapy, steroid administration, and negative suction application (suction pressure of -20 cm H2O) in the right pleural cavity for five days, the right lung could be fully expanded without development of reexpansion pulmonary edema, and the reexpansion pulmonary edema in the left lung resolved. Although it is a very rare condition, it is important to know that contralateral occurrence of reexpansion pulmonary edema can occur, especially when the ipsilateral lung is collapsed. Being aware of this potential condition can allow for early and proper management. [ABSTRACT FROM AUTHOR]

In order to induce greater light absorption, nano-patterning is often applied to the metal-oxide buffer layer in inverted bulk-heterojunction(BHJ) solar cells. However, current homogeneity was significantly disturbed at the interface, leading to an efficiency that was not fully optimized. In this work, an additional PC61BM layer was inserted between the ZnO ripple and the photoactive layer to enhance the electron extraction. The insertion of additional PC61BMlayer provided substantial advantages in the operation of inverted BHJ solar cells; specifically, it enhanced current homogeneity and lowered accumulation and trapping of photogenerated charges at the ZnO interface. Inclusion of the additional PC61BM layer led to effective quenching of electron-hole recombination by a reduction in the number of accumulated charges at the surface of ZnO ripples. This resulted in a 16% increase in the efficiency of inverted BHJ solar cells to 7.7%, compared to solar cells without the additional PC61BM layer. [ABSTRACT FROM AUTHOR]

Background Tension pneumothorax is a life-threatening occurrence that is infrequently the consequence of spontaneous pneumothorax. The aim of this study was to identify the risk factors for the development of tension pneumothorax and its effect on clinical outcomes. Methods We reviewed patients who were admitted with spontaneous pneumothorax between August 1, 2003 and December 31, 2011. Electronic medical records and the radiological findings were reviewed with chest x-ray and high-resolution computed tomography scans that were retrieved from the Picture Archiving Communication System. Results Out of the 370 patients included in this study, tension pneumothorax developed in 60 (16.2%). The bullae were larger in patients with tension pneumothorax than in those without (23.8 ± 16.2 mm vs 16.1 ± 19.1 mm; P = 0.007). In addition, the incidence of tension pneumothorax increased with the lung bulla size. Fibrotic adhesion was more prevalent in the tension pneumothorax group than in that without (P = 0.000). The bullae were large in patients with fibrotic adhesion than in those without adhesion (35.0 ± 22.3 mm vs 10.4 ± 11.5 mm; P = 0.000). On multivariate analysis, the size of bullae (odds ratio (OR) = 1.03, P = 0.001) and fibrotic adhesion (OR = 10.76, P = 0.000) were risk factors of tension pneumothorax. Hospital mortality was 3.3% in the tension pneumothorax group and it was not significantly different from those patients without tension pneunothorax (P = 0.252). Conclusions Tension pneumothorax is not uncommon, but clinically fatal tension pneumothorax is extremely rare. The size of the lung bullae and fibrotic adhesion contributes to the development of tension pneumothorax. [ABSTRACT FROM AUTHOR]

Background: Reexpansion pulmonary edema (REPE) is known as a rare and fatal complication after tube thoracostomy. Objectives: We investigated the risk factors for the development of REPE in patients with spontaneous pneumothorax. Methods: We selected patients who were diagnosed with spontaneous pneumothorax and were initially treated with tube thoracostomy between August 1, 2003 and December 31, 2011. The patients' electronic medical records, including operative notes and chest x-ray and computed tomography scans, were reviewed. Results: REPE developed in 49 of the 306 patients (16.0%). REPE was more common in patients with diabetes (14.3% vs 3.9%, P = 0.004) or tension pneumothorax (46.8% vs 16.2%, P = 0.000). The pneumothorax was larger in patients with REPE than without REPE (57.0 ± 16.0% vs 34.2 ± 17.6%, P = 0.000), and the incidence of REPE increased with the size of pneumothorax. On multivariate analysis, diabetes mellitus [(odds ratio (OR) = 9.93, P = 0.003), and the size of pneumothorax (OR = 1.07, P = 0.000) were independent risk factors of REPE. Conclusions: The presence of diabetes increases the risk of REPE development in patients with spontaneous pneumothorax. The risk of REPE also increases significantly with the size of pneumothorax. [ABSTRACT FROM AUTHOR]

The crystalline volume of nanocrystalline silicon (Si) films could be successfully controlled simply by changing the substrate scan speed at the high working pressure of 300 Torr. The Si crystalline volume fraction was increased from 30% to 57% by increasing the scan speed from 8 to 30 mm/s. When the Si film was prepared at a low scan speed (8 mm/s), Si crystals of size 5 nm grew homogeneously through the whole film. The higher scan speed was found to accelerate crystallization, and crystals of size up to 25 nm were deposited in the Si film deposited when the scan speed was 30 mm/s. [ABSTRACT FROM AUTHOR]

The effect of abnormal grain growth on the formation of amorphous films at grains boundaries was studied in a model system BaTiO3. 0.4 mol% TiO2-excess BaTiO3 powder compacts were sintered at 1380°C for various times up to 16 h. During the sintering, abnormal grains formed. With the growth of the abnormal grains, amorphous films formed and eventually thickened up to 19.2 nm at grain boundaries. The film formation is attributed to the accumulation of Ti solutes at grain boundaries with the grain growth, while the film thickening is mostly caused by the redistribution of liquid at triple junctions. Extended annealing of the 16-h-sintered sample at 1350°C for 15 days resulted in a thinning of the film to nearly 1.7 nm without a change in the grain size, showing an equilibrium thickness. This result demonstrates that the film thickness observed during the growth of the grain may not be the equilibrium thickness. The result further suggests that the shape of the abnormal grains, even when equiaxed, can differ from the equilibrium shape. [ABSTRACT FROM AUTHOR]

The effect of additions of ≤1 mol% Al2O3 on abnormal grain growth in BaTiO3 sintered for periods of ≤60 min at 1350°C has been studied. Addition of ≤0.2 mol% Al2O3 caused an increase in the nucleation and growth rates of abnormal grains, with further additions causing a decrease. This behavior is explained by interface-controlled growth. Dopant adsorption reduces both the edge free energy and the step velocity of a grain, causing the nucleation and growth rates of abnormal grains to increase, pass through a maximum, and then decrease with increasing dopant concentration. [ABSTRACT FROM AUTHOR]

Traumatic hemothorax is usually associated with obvious organ injuries, such as rib fractures, pulmonary injuries, and other mediastinal injuries. We present a rare case in which a 42-year- old Korean man who fell off of a roof, approximately 3 meters in height, resulting in a life-threatening hemothorax without obvious injuries to the thoracic organs. Chest CT showed a large amount of hemothorax in the right side of the thoracic cavity, and an active bleeding, presumably from the posterior intercostal or the phrenic artery, with a focal aneurysmal change. The emergency thoracotomy was performed to bring the active bleeding under control. The operative findings showed there were only the inferior pulmonary ligament tears, and the active bleeding from it. The postoperative course was uneventful and the patient was discharged without any complications. We should consider the inferior pulmonary ligamental injury as one of causes for traumatic hemothorax. [ABSTRACT FROM AUTHOR]

Mycotic aneurysms in the aortic arch are extremely rare and represent a challenging surgical problem. Although surgery is the standard treatment, application of endovascular repair has been extended, but this technique carries a concern regarding the interposition of an artificial graft in the infected lesion. We present the case of an infected pseudoaneurysm in the thoracic aorta which was successfully excluded by treatment with a stent graft. [ABSTRACT FROM AUTHOR]

We report a case of 46-year-old male with simultaneous bilateral spontaneous tension pneumothorax. Severe reexpansion pulmonary edema developed after bilateral tube thoracoscomy, but he was recovered after 2 days ventilator care. After bilateral wedge resection and talc pleurodesis, he was discharged without complications and had remained well and without recurrence during the 8-year follow-up. [ABSTRACT FROM AUTHOR]

Chylopericardium usually occurs secondary to trauma, cardiothoracic surgery, radiation therapy, or neoplasm of the mediastinum. Idiopathic chylopericardium is extremely rare. We report a case of primary chylopericardium in a 79-year-old male patient. Although pericardial window and thoracic duct ligation are the treatment of choice, the patient has been doing well for six months since video-assisted thoracoscopic pericardial window. [ABSTRACT FROM AUTHOR]

We report a case of a 23-year-old woman with a 5-year history of recurrent hemoptysis during menstrual period. Catamenial hemoptysis was diagnosed using chest computed tomography and bronchoscopic examination during menstruation. The patient was managed successfully with wedge resection and has been free of recurrence for 5 years. We suggest that surgery is an effective treatment, and complete resection with accurate localization is important for the prevention of recurrence. [ABSTRACT FROM AUTHOR]

It is demonstrated that either a strong nonlinear or a nearly Ohmic behavior in current-voltage relationship can be distinctively represented in Sc-doped polycrystalline CaCu3Ti4O12, with variation in the initial composition of samples. Through conductive atomic force microscopy and impedance spectroscopy, such a definitive difference in the electrical property was found to depend on the presence of a large electrostatic barrier at the grain boundaries. The effect of Sc ions on the boundary potential barrier and the conductance of single grains is discussed. Findings suggest a different site selectivity of Sc in the lattice in terms of the initial cation stoichiometry. [ABSTRACT FROM AUTHOR]

Utilizing high-resolution electron microscopy and image simulation, it is demonstrated that some of the crystal lattices of Fe-doped CaCu3Ti4O12 are intrinsically bent at the nanometer scale. A comparison between experimentally obtained and simulated images indicates that the bending angle is of a few milliradians, which is remarkable in a brittle oxide. Despite such lattice distortion, much of the lattice strain induced by the distortion appears to be released at the domain walls where a number of misfit dislocations are present. [ABSTRACT FROM AUTHOR]

In this letter, we report on dielectric and leakage current characteristics of room temperature deposited Bi1.5Zn1.0Nb1.5O7 (BZN) films on the basis of crystallographic structure and suitability of BZN gate insulators as key building blocks in the fabrication of low voltage operating ZnO based thin-film transistors (TFTs). The BZN films exhibited a high dielectric constant (∼51) and good leakage current characteristics (∼10-7 A/cm2) at an applied voltage of 5 V. All room temperature processed ZnO based TFTs using BZN gate insulator exhibited field effect mobility of 1.13 cm2/Vs and low voltage device performance less than 4 V. [ABSTRACT FROM AUTHOR]

By doping a few atomic percent of 3d-block cations, we demonstrate that the high dielectric response in CaCu3Ti4O12 can be reduced by a factor of ∼103 at room temperature. Each of the added dopants shows its own preferential substitution on either Cu or Ti sites. The dopants that act as acceptors have a critical impact on the disappearance of the electrostatic potential barrier at grain boundaries, resulting in drastically decreased permittivity values of <90 without voltage dependence. The present doping experiment directly shows that the potential barrier at internal interfaces is a key factor for the peculiar dielectric phenomena. [ABSTRACT FROM AUTHOR]

Using an embedded single crystal in a polycrystalline matrix and quantitative electron energy loss spectroscopy, we have demonstrated that Ti-excess grain boundary nonstoichiometry can vary with the extent of boundary migration. While a slight excess in Ti was detected at the boundaries between small matrix grains, a large increase in Ti/Ba ratio, to as much as ∼1.50 compared to the stoichiometric value, was present at the interface between a growing single crystal and the matrix grains when the embedded crystal grew up to a few hundred micrometers. This change in nonstoichiometry was attributed to a continuous accumulation of excessive Ti at the moving boundary during crystal growth. The present result indicates that growth kinetics can critically affect the interface chemistry in polycrystals. [ABSTRACT FROM AUTHOR]

To study the effect of oxygen partial pressure on grain growth in BaTiO[sub 3], TiO[sub 2]-excess samples have been sintered in air with and without a prior Hz heat treatment. Without prior H[sub 2] treatment, abnormal grain growth occurs below and above the eutectic temperature (T[sub e]). An introduction of Hz treatment before air sintering, however, increases the average grain size and suppresses the formation of abnormal grains during subsequent air sintering below and above T[sub e]. This H[sub 2] treatment effect has been explained in terms of a decrease of the driving force for the growth of faceted grains below a critical value for formation of abnormal grains. The observed graingrowth behavior under various atmospheres demonstrates the possibility of having various microstructures via control of oxygen partial pressure and initial grain size. [ABSTRACT FROM AUTHOR]

Pericardial cysts are occasionally encountered and successfully excised using video-assisted thoracoscopic surgery (VATS). However, cardiac cysts originating from the epicardium are extremely rare. Herein, we report an epicardial cyst that was completely excised using VATS. The epicardial cyst had a feeding vessel from the left ventricle and was considered to originate from the left ventricle. To the best of our knowledge, this case is the first to report excision of an epicardial cyst using VATS. [ABSTRACT FROM AUTHOR]