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The augmented thermoelectric performance of nanocrystalline antimony telluride (Sb2Te3) films is investigated by introducing interfacial energy-barrier scattering (i.e., barrier heights), which occurs at both the grain boundaries and the interfaces with embedded second phases. It is postulated that the barriers created at both the interfaces and boundaries filter the low-energy carriers, thus favoring a high Seebeck coefficient. A facile, but high-precision composition-controlled electrodeposition technique is employed to synthesize single-phase nanocrystalline Sb2Te3 and nanocomposite Te/Sb2Te3. Both the initial composition of the Sb-Te solid solution and the post-annealing profiles are varied to control the grain size, as well as the formation of second-phase Te. The electrical and thermoelectric properties are measured and correlated with the physical properties, where an enhanced Seebeck coefficient at a fixed carrier concentration is interpreted as indicating that the energy-dependent carrier filtering effect is in force. On a promising note, modification of the Sb2Te3 film physical properties and formation of the second phase affect the interfacial energy-barrier scattering and yields an enhanced power factor. Thus, Sb2Te3 film is a promising p-type thermoelectric material for a room-temperature-operational micro-thermoelectric power generator.

We synthesize a hierarchically porous electrode material with a high specific capacity composed of nickel oxide (NiO) nanosheets and perforated graphene (PG) sheets grown on a three-dimensional (3D) macroporous nickel foam via a facile hydrothermal method. Employing perforated graphene instead of non-perforated graphene greatly improves the electrochemical performance of the composite by increasing the specific surface area of the NiO/PG composite owing to the small perforations in the graphene and by improving the mechanical strength and electrical conductivity of NiO due to the graphene covering layer. The PG also provides (a) the accessibility and diffusion of ions onto NiO and PG surfaces through the perforations; (b) the electrolyte cages in the spaces below the perforations to allow ion-reversible adsorption to the inner surface of the graphene; (c) the inevitable edge defects around the holes causing reactivity with ions. After assembling an asymmetric supercapacitor coin cell composed of NiO/PG as the positive electrode, a separator, PG as the negative electrode, and a 1 M KOH electrolyte, the coin cell exhibits a high energy density of 57.8 W h kg−1 at a power density of 1030.9 W kg−1 and excellent cycling stability (82.1%) after 10 000 cycles.

With the advent of coherent X-ray sources, X-ray refraction has begun to be utilized for X-ray imaging of unprecedented sensitivity. The aim of this study was to develop a wave propagation simulator that provides a map of X-ray refraction after passing through an object. We applied the Fresnel diffraction integral for calculating the propagated wave and then obtained the refraction map by differentiating the phase in the refraction-analyzing direction. The simulation was validated by comparing the computed tomography (CT) reconstruction of a virtual phantom with its map of refractive index: the deviations were below 0.7% for soft tissues under our test condition. The simulator can be used for testing and developing highly-sensitive X-ray imaging techniques based on X-ray refraction analysis prior to experimentation.

Three-dimensional (3D) metal/cuprous oxide (Cu2O) micro-pillar arrays were fabricated by electroless deposition of Ni on Si micro-pillars followed by the electrochemical deposition of Cu2O on the metal micro-pillars. The metal micro-pillars with heights of 16 μm and diameters of 1–1.5 μm showed low reflectance and conductance values similar to Cu2O plates, indicating that the 3D metal/Cu2O micro-pillars are good current collectors. The photocurrent of the 3D metal/Cu2O micro-pillar arrays was more than twice that of the Cu2O plates. This high photocurrent for the 3D metal/Cu2O micro-pillar results from its large surface area, long optical absorption depth (micro-pillar length) and short carrier diffusion length (thin Cu2O absorber).

Silver antimony telluride (AgSbTe2) thin films were fabricated by a simple and cost-effective electrodeposition method for the first time. To investigate the effects of crystallinity and composition on the films’ thermoelectric (TE) properties, amorphous AgxSbyTez solid solutions of various compositions were electrodeposited by tailoring the [Ag+] concentration in the electrolytes, followed by a thermally driven solid-state amorphous-to-nanocrystalline phase transition. Because of the lower carrier concentration in the nanocrystalline phases, higher Hall mobility and Seebeck coefficients, almost twice as high as those observed in the bulk materials, resulted in enhanced power factors of 90–553 μW/mK2. The maximum power factor was obtained from stoichiometric AgSbTe2 thin films. The reported power factors are highly comparable to other values reported for electrodeposited p-type V–VI compounds. The improvement achieved in the TE properties of electrodeposited AgSbTe2 thin films demonstrates the feasibility of the use of these films as p-type legs in room-temperature operations.

s A significant obstacle to obtaining enhanced thermoelectric performance (defined by a thermoelectric figure of merit, zT) in commercial p-type Bi-Sb-Te alloys is bipolar transport originating from their intrinsic narrow-band-gap semiconducting characteristics. Cation-site doping is commonly used to suppress the bipolar conduction. However, zT enhancement occurs often only at elevated temperatures since the electronic thermal conductivity mainly increases at low temperatures due to the increase of hole concentration. Herein, the substitution of isovalent S ions in the anion Te-site of Bi-Sb-Te is explored to obtain a high zT over a wide temperature range by simultaneously increasing the density-of-states effective mass and weighted mobility. The zT of Bi0.49Cu0.01Sb1.5Te3 is enhanced by ~10 % for all measured temperatures, and the average zT increases beyond 1.0 between 300 and 520 K, benefitting from the synergetic control of band structure and deformation potential via S substitution.

The carbonation of cement paste changes its microstructural characteristics. The porosity of the cement paste microstructure is reduced when calcite is produced from the reaction between portlandite and carbon dioxide. In this study, such microstructural changes were investigated using image analyses of the 3D microstructures obtained with synchrotron micro-computed tomography (CT). When two sets of samples were subjected to different degrees of carbonation, the porosity and pore size reductions were identified from the micro-CT images. The formation of calcite caused by the reaction of portlandite was indirectly identified by the reduction of the mean grayscale value or linear attenuation coefficient (LAC) of the solid phase voxels. It was confirmed that micro-CT could also be used as a supplementary tool for the analysis of the microstructural evolution of cement paste under carbonation.

Metal Chalcogenide nanostructures have been extensively implemented for high-performance thermoelectric applications, which can directly convert waste-heat-energy into electricity, with the support of theoretical and empirical results. In fact, finding a novel and cost effective synthesis approach that facilitates the formation of stable and reproducible nanostructured thermoelectric materials determines the commercial applicability. The overall objective of this work is to synthesize metal chalcogenide nanostructures with outstanding thermoelectric performance by an electrodeposition technique, which is one of the most versatile methods for low dimensional nanostructures in a cost effective and scalable manner. Precise control over dimension, chemical composition, crystallinity, crystal structure, grain size, preferred orientation, and the attainment of nanoinclusions and/or intermediate phases based on thermodynamically favored solid-state phase transition yields optimal electrical transport and thermoelectric properties of the metal chalcogenide nanostructures. Herein, the electrodeposited nanostructures represented the enhancement of Seebeck coefficient without reducing the conductivity was investigated that was explained by a carrier energy filtering effect due to the band bending at the two-phase interfaces.

The best thermoelectric materials should have low thermal conductivity (κ) and high Seebeck coefficient (S) and electrical conductivity (σ). However, the three parameters, which constitute ZT (ZT = S2σT/κ), are interdependent on each other. Advances in high-ZT thermoelectric materials have been mostly achieved by optimizing material composition and modifying the nanostructure of inorganic materials. However, the inorganic thermoelectric materials are generally less abundant, expensive, and toxic. Recently, researches have been focused on polymer-based thermoelectric materials in order to overcome these limitations of inorganic materials. In particular, conducting polymers have attracted great attention as promising thermoelectric materials because of their unique advantages such as low thermal conductivity, flexibility, low cost, and low toxicity. However, the typical ZT value of the conducting polymer-based materials are on the order of 10−2 ~ 10−3 and are much lower than those of inorganic materials. It is essential to enhance the Seebeck coefficient without decreasing the electrical conductivity. The poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is one of the most promising materials. Water soluble PEDOT:PSS is already widely used for thermoelectrics as a base material for composition between inorganic and organic materials. It can be also modified by a secondary doping according to adding high boiling point cosolvents to increase its conductivity more than 1000 S/cm. Among the cosolvents, ethylene glycol (EG), which is miscible with water and has a boiling point of 189 °C, is one of the most commonly used cosolvents for this purpose. Interestingly, the one-dimensionally aligned inorganic structures can also allow for more effective thermal and electrical energy transfer as forming the hybrid microstructures with the conducting PEDOT:PSS, because the number of inorganic-organic interface grain boundaries that cause energy loss is lower than that in the case of randomly dispersed structures. Moreover, the aligned structures transfer the produced energy to the neighboring structures more effectively. These characteristics of the aligned structures can prevent the cancellation of charge carrier movements among the core materials and can produce the relative enhancement of the energy generation. In this study, we have demonstrated the developed thermoelectric properties of ethylene glycol (EG)-doped poly(3,4-ethylenedioxythiophene): poly(4-styrenesulfonate) (PEDOT:PSS)/Se nanowires hybrid composites film on the flexible PDMS substrate (PEDOT:PSS-Se/PDMS). The amount of EG added to the PEDOT:PSS solutions was optimized by measuring the σ , using a conventional four-probe method. As the EG concentration increased from 0 to 10%, σ increased to ~ 1000 S/cm. We have demonstrated in tuning the barrier energy difference of between PEDOT:PSS and Se via the EG doping. The S can be maximized up to 121.6 μV/K through optimization of PEDOT:PSS-Se/PDMS barrier energy according to so-called energy filtering effect. The power factor of the fabricated EG 8%-doped PEDOT:PSS-Se/PDMS composite film was 1.59 mW/mK2 at 30 °C. The electrical conductivity can be also enhanced simultaneously owing to the EG-induced π - π stacking among PEDOT chains. This work provides a smart approach to design and modulate the thermoelectric properties of conducting polymer/inorganic nanostructure composites. This study also shows that flexible thermoelectric devices based on cheap conducting polymers have great potential in wearable electronics. Figure 1

We propose a 3D-shape preferred orientation (SPO) measurement method of rigid grains using synchrotron micro-computational tomography (&mu, CT). The method includes oriented sampling, 3D &mu, CT imaging, image filtering, ellipsoid fitting, and SPO measurement. After CT imaging, all processes are computerized, and the directions of thousands of rigid grains in 3D-space can be automatically measured. This method is optimized for estimating the orientation of the silt-sized rigid grains in fault gouge, which indicates P-shear direction in a fault system. This allows us to successfully deduce fault motion sense and quantify fault movement. Because this method requires a small amount of sample, it can be applied as an alternative to study fault systems, where the shear sense indicators are not distinct in the outcrop and the fault gouge is poorly developed. We applied the newly developed 3D-SPO method for a fault system in the Yangsan fault, one of the major faults in the southeastern Korean Peninsula, and observed the P-shear direction successfully.

The crystallization of MAPbI3 perovskite films was purposefully engineered to investigate the governing factors which determine their morphological properties and moisture stability. By modulating nucleation, we obtained a single layer perovskite film with controlled crystal facet orientation and grain size. The lack of perovskite nucleation sites during crystallization allowed us to tailor the resulting crystallization phase. Theoretical calculations indicated that the nucleation sites for perovskite growth are related to the electron density around the oxygen atom (C[double bond, length as m-dash]O and S[double bond, length as m-dash]O) in a Lewis base. A single layer of micrometer-sized and (110)-oriented perovskite crystals was achieved in the optimized MAPbI3 films via suppressing the formation of nucleation sites. We fabricated inverted perovskite solar cells with the structure of glass/ITO/PEDOT:PSS/MAPbI3/PC61BM/Al which exhibited a high power conversion efficiency of 17.5% and a high fill factor over 83%. In addition, a study of the moisture stability indicated that the (110) facet orientation of the perovskite grains plays a more important role in film degradation than grain size.

The regeneration of bone defects caused by periodontal disease or trauma is an important goal. Porous hydroxyapatite (HA) is an osteoconductive graft material. However, the hydrophobic properties of HA can be a disadvantage in the initial healing process. HA can be coated with TiO2 to improve its hydrophilicity, and ultraviolet irradiation (UV) can further increase the hydrophilicity by photofunctionalization. This study was designed to evaluate the effect of 5% TiO2-coated HA on rabbit calvarial defects and compare it with that of photofunctionalization on new bone in the early stage. The following four study groups were established, negative control, HA, TiO2-coated HA, and TiO2-coated HA with UV. The animals were sacrificed and the defects were assessed by radiography as well as histologic and histomorphometric analyses. At 2 and 8 weeks postoperatively, the TiO2-coated HA with UV group and TiO2-coated HA group showed significantly higher percentages of new bone than the control group (p &lt, 0.05). UV irradiation increased the extent of new bone formation, and there was a significant difference between the TiO2-coated HA group and TiO2-coated HA with UV group. The combination of TiO2/HA and UV irradiation in bone regeneration appears to induce a favorable response.

We managed a case of extrinsic airway compression by adjacent structures in a 1-month-old boy with right lung agenesis and dextro-rotated heart using anterior aortopexy and near total thymectomy.

This study addresses the usability of synchrotron radiation micro-computed tomography (SR-μCT) for the high-throughput examination of bone biopsy specimens harvested from maxillary sinus floor elevation (MSFE) patients. The experimental procedure devised for efficient data acquisition and volume analysis of bone biopsy specimens of sinus lift using SR-μCT is presented. The measuring was done in approximately one minute per field of view; 3D image visualization and volume analysis could be performed in one hour. Six months after the sinus floor augmentation procedure, bone biopsy specimens were collected. Six specimens were studied. The percentages of bone measured by 3D volumetric analysis using SR-μCT and 2D area analysis using conventional histomorphometry were compared. A specimen was measured in any cross section, and the analysis was readily extended to the entire volume of the specimen. Significant differences between the 2D and the 3D measurement results were revealed. Based on our observations, we report structural inhomogeneity in the grafted volume of the MSFE site. The new bone volume assessed by SR-μCT correlates with the percentage of bone as assessed by conventional 2D histologic photomicrographs. SR-μCT is thus a reliable technique to determine the volume of newly formed bone at the MSFE.

Background We reviewed our revised surgical strategy for tetralogy of Fallot (TOF) total correction to minimize early exposure to significant pulmonary regurgitation (PR) and to avoid right ventriculotomy (RV-tomy). Methods and Results: Since February 2016, we have tried to preserve, first, pulmonary valve (PV) function to minimize PR by extensive commissurotomy with annulus saving; and second, RV infundibular function by avoiding RV-tomy. With this strategy, we performed total correction for 50 consecutive patients with TOF until May 2018. We reviewed the early outcomes of 27 of 50 patients who received follow-up for ≥3 months. Mean patient age at operation was 10.2±5.0 months, and mean body weight was 8.8±1.2 kg. The preoperative pressure gradient at the RV outflow tract and the PV z-score were improved at most recent echocardiography from 82.0±7.1 to 26.8±6.4 mmHg, and from -2.35±0.49 to -0.55±0.54, respectively, during 11.1±1.6 months of follow-up after operation. One patient required re-intervention for residual pulmonary stenosis. Twenty-two patients had less than moderate PR (none, 1; trivial, 8; mild, 13), and 5 patients had moderate PR. There was no free or severe PR. Conclusions At 1-year follow-up, the patients who underwent total TOF correction with our revised surgical strategy had acceptable results in terms of PV function. The preserved PV had a tendency to grow on short-term follow-up.

Purpose Hydroxyapatite treated with recombinant human bone morphogenetic protein-2/Hydroxyapatite (rhBMP-2/HA) or bovine bone was applied on extraction sockets for alveolar ridge preservation, and the results were compared with respect to clinical and histological bone formation. Materials and methods This was a prospective, randomized controlled clinical trial performed on 20 implant placement sites (10 in the experimental and 10 in the control group). rhBMP-2/HA was applied on extraction sockets in the experimental group and bovine bone on those of the control group. The bone at the corresponding sites was biopsied 3 months later, and clinical, histological, and histomorphometric analyses were performed. Results The alveolar bone height was well preserved in both groups with relatively less change in width in the experimental group compared with the control group. The percentage of new bone was 25.37% ± 17.23% in the experimental group and 6.13% ± 4.32% in the control group; the difference was statistically significant. Conclusions The alveolar ridge was preserved clinically and histologically in both groups. rhBMP-2/HA resulted in greater new bone formation than bovine bone 3 months after the surgery.

The hydrophilicity of bone graft material generally used as a carrier can play an important role in regulating bone morphogenetic protein (BMP) expression at the bone graft site. The hydrophilicity, altering physicochemical properties, and enhancing biological capabilities, can be increased via surface modification through ultraviolet (UV) photofunctionalization and the effect on de novo osteogenesis could be further improved. Therefore, this study aimed to assess the effects of UV-irradiated TiO

In this paper, we propose a cone transform method, which is robust against size variations in object recognition. A main problem in computer vision is that objects may show large size variations. This makes it difficult to develop robust object recognition algorithms since most recognition algorithms assume certain target size ranges. The proposed method represents an input image by two angles. The first angle is measured from a center point counter-clockwise and the other angle is measured from the radius. The proposed method shows better tolerance against size variations. Experiment results show that the proposed method provided better classification performance when objects were reduced in size.

Screen printing of commercially available Ag paste is the most widely used method for the front side metallization of Si solar cells. However, the metallization using Ag paste is expensive and needs high temperature annealing for reliable contact. Among many metallization schemes, Ni/Cu/Sn plating is one of the most promising methods due to low contact resistance and mass production, resulting in high efficiency and low production cost. Ni layer serves as a barrier which would prevent copper atoms from diffusion into the silicon substrate. However, Ni based schemes by electroless deposition usually have low thermal stability, and require high annealing process due to phosphorus content in the Ni based films. These problems can be resolved by adding W element in Ni-based film. In this study, Ni-W-P alloys were formed by electroless plating and properties of it such as sheet resistance, resistivity, specific contact resistivity, crystallinity, and morphology were investigated before and after annealing process by means of transmission line method (TLM), 4-point probe, X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM).

Recently, -based alloys are the best thermoelectric materials near to room temperature, so it has been researched to achieve increased figure of merit(ZT). Ternary compounds such as Bi-Te-Se and Bi-Sb-Te have higher thermoelectric property than binary compound Bi-Te and Sb-Te, respectively. Compared to DC plating method, pulsed electrodeposition is able to control parameters including average current density, and on/off pulse time etc. Thereby the morphology and properties of the films can be improved. In this study, we electrodeposited n-type ternary Cu-doped thin film by modified pulse technique at room temperature. To further enhance thermoelectric properties of thin film, we optimized Cu doping concentration in thin film and correlated it to electrical and thermoelectric properties. Thus, the crystal, electrical, and thermoelectric properties of electrodeposited thin film were characterized the XRD, SEM, EDS, Seebeck measurement, and Hall effect measurement, respectively. As a result, the thermoelectric properties of Cu-doped thin films were observed that the Seebeck coefficient is and the power factor is at 10 mg of Cu weight. The power factor of Cu-doped thin film is 1.4 times higher than undoped thin film.

Doping with foreign atom has been shown to be an effective way to enhance the dimensionless figure of merit ZT of Bi2Te3-based thermoelectric raw materials. Herein, we report that doping with Nb is effective in enhancing the Seebeck coefficient of n-type Cu0.008Bi2Te2.7Se0.3 polycrystalline bulks. Considering compensation of the Seebeck coefficient due to decrease of the electrical conductivity in Nb-doped compositions, the absolute value of Seebeck coefficient rather increased benefiting from an enhancement of the density of states (DOS) effective mass m* from 1.09m 0 (Cu0.008Bi2Te2.7Se0.3) to 1.21m 0 − 1.27m 0 (Cu0.008Bi2−x Nb x Te2.7Se0.3) due to a DOS engineering effect. The values of ZT were 0.84 at 300 K and 0.86 at 320 K for Cu0.008Bi1.99Nb0.01Te2.7Se0.3. This compositional tuning approach highlights the possibility of further enhancement of ZT for n-type Bi2Te3-based compounds by using a combination of nanostructuring technologies to reduce the thermal conductivity.

Insulating concrete is a type of concrete that is designed to reduce thermal conductivity. Insulating concrete contains numerous voids that play an important role in reducing heat conduction. Therefore, appropriate nondestructive methods are required to examine the spatial distribution of voids and constituents in a concrete specimen. In this study, an insulating concrete specimen containing hollow glass beads to increase the insulating effect is adopted. Then, micro computed tomography (CT) is used to investigate the spatial distribution of the voids in this specimen. By using a micro CT device, a series of cross-sectional images of the specimen at micrometer-order pixel size are generated by X-rays. To quantitatively describe the spatial distribution of voids in the specimen, probability functions such as two-point correlation, lineal-path, and two-point cluster functions are adopted. In addition, the thermal conductivity of the specimen is evaluated using finite element simulation. The results clarify the insulating effect of glass beads on the concrete specimen and reveal a strong relationship between the probabilistic characteristics of the void distribution and the material responses of insulating concrete.

Cu2O microcrystals (MCs) and nanocrystals (NCs) of various shapes were potentiostatically deposited on Ti substrates by exploiting the capping effects of differently charged surfactants on certain surfaces. Positively charged hexamethylenetetramine was adsorbed onto the {111} and {100} planes of the Cu2O crystals (copper- and oxygen-terminated surface) while negatively charged poly(vinylpyrrolidone) was adsorbed onto the {111} planes (Cu-terminated surface due to Coulombic interaction). The difference in the adsorption behaviors of the two surfactants resulted in the synthesis of differently shaped Cu2O MCs. We were also able to systematically control the shape evolution of Cu2O NCs synthesized as cubes, truncated cubes, truncated octahedrons, and stepped octahedrons into perfect octahedrons by adding or removing surfactants successively during the electrochemical deposition process. This method is a simple, flexible, and cost-effective one and should aid in the elucidation of the shape-transformation phe...

급성 췌장염은 대부분 술이나 담석에 의해 발생하며, 10% 에서는 중증의 급성 괴사성 췌장염이 발생하여 사망을 초래 할 수 있다. 여러 가지 약물로도 급성 췌장염이 유발될 수 있 으며 전체 급성 췌장염 환자 중 1.4%로 보고되고 있다. Bortezomib는 미국연방식약청에서 새롭게 진단된 다발성 골수종과 재발된 다발성 골수종 치료제로 처음 인정된 프로 테아좀 억제제로서 널리 사용되고 있다. Bortezomib의 부작 용은 혈소판 감소, 위장관 장애(오심, 구토, 설사, 변비), 말초 신경변증, 열, 피로, 호흡곤란, 근육통이 대부분이다. Bortezomib에 의한 급성 췌장염이 매우 드물게 발생하여 국외에 서는 8예가 보고되었고, 국내에서는 보고된 적이 없다. 저 자들은 다발성 골수종을 치료하는 중에 발생한 급성 췌장염 을 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

X-ray can be applied to obtain a projection image of an object. It is not easy to obtain an high quality image for the object composed of low and high density materials. For the object with large difference in density, it is possible to realize high contrast image using images of low and high tube voltages and image processing. The plastic and metalic parts of the electronic components can be imaged by the dual energy technique which use low and high tube voltages and by processing pixel-by-pixel using visual C++. The contrast-enhanced image can be used to detect and observe defects within the electronic components.

In this work, we demonstrate an enhancement of thermoelectric properties by creating γ-SbTe/Sb2Te3 nanocomposite film, where γ-SbTe nanoinclusions are embedded in a nanocrystalline Sb2Te3 matrix. The two-phase nanocomposite was formed via solid-state phase transition using an amorphous Sb2Te3 electrodeposits as the starting materials. The crystallinity and crystal structure of intermediate states during the amorphous-crystalline solid-state transformation were characterized by sequentially annealing the sample. The formation of the γ-SbTe is attributed to the different enthalpy of mixing for the bonding structures available in the Sb–Te system. Room temperature measurement of electrical and thermoelectrical properties as a function of annealing temperature revealed that the two-phase system provided the carrier energy filtering effect at the interfaces between two phases, leading to enhanced Seebeck coefficient without affecting its electrical transport properties. The band bending at the two-phase interfaces was indirectly manifested by measuring their difference in the valence band, advocating the possibility of a strong energy-dependent charge scattering to the enhanced Seebeck coefficient.

Bismuth telluride (Bi 2 Te 3 ) thin films were electrodeposited at room temperature from nitric baths in the presence of a surfactant, cetyltrimethylammonium bromide (CTAB). Nearly stoichiometric Bi 2 Te 3 thin films were obtained from electrolytes containing 7.5 mM Bi(NO 3 ) 3 . The surface morphology and mechanical properties of the electrodeposited thin film were improved by the addition of CTAB to the electrolyte, while the electrical and thermoelectric properties were preserved. Post-deposition annealing in a reducing environment did not improve the electrical and thermoelectric properties, possibly because the change in the microstructure of the Bi 2 Te 3 thin film was too small.

We have developed a high performance supercapacitor cathode electrode composed of well dispersed MnCO3 quantum dots (QDs, ∼1.2 nm) decorated on nickel hydrogen carbonate–manganese carbonate (Ni(HCO3)2–MnCO3) hedgehog-like shell@needle (MnCO3 QDs/NiH–Mn–CO3) composites directly grown onto a 3D macro-porous nickel foam as a binder-free supercapacitor electrode by a facile and scalable hydrothermal method. The MnCO3 QDs/NiH–Mn–CO3 composite electrode exhibited a remarkable maximum specific capacitance of 2641.3 F g−1 at 3 A g−1 and 1493.3 F g−1 at 15 A g−1. Moreover, the asymmetric supercapacitor with MnCO3 QDs/NiH–Mn–CO3 composites as the positive electrode and graphene as the negative electrode showed an energy density of 58.1 W h kg−1 at a power density of 900 W kg−1 as well as excellent cycling stability with 91.3% retention after 10 000 cycles, which exceeded the energy densities of most previously reported nickel or manganese oxide/hydroxide-based asymmetric supercapacitors. The ultrahigh capacitive performance is attributed to the presence of the high surface area core–shell nanostructure, the well dispersed MnCO3 quantum dots, and the high conductivity of MnCO3 quantum dots as well as the synergetic effect between multiple transition metal ions. The superior supercapacitive performance of the MnCO3 QDs/NiH–Mn–CO3 composites makes them promising cathode materials for high energy density asymmetric supercapacitors.

Background Mono-capillary optics have been applied to increase the performance of X-ray instruments. However, performance of a mono-capillary optic strongly depends on the shape accuracy, which is determined by the diameters of the inner hollow of the capillary along the axial direction. Objective To precisely determine the inner diameter of the capillary optic used in X-ray imaging technique, which aims to replace the conventional method using a visible microscope. Methods High spatial resolution X-ray images of the mono-capillary optic were obtained by a synchrotron radiation beamline. The inner diameter of the mono-capillary optic was measured and analyzed by the pixel values of the X-ray image. Result Edge enhancement effect was quite useful in determining the inner diameter, and the accuracy of the diameter determination was less than 1.32 μm. Many images obtained by scanning the mono-capillary optic along the axial direction were combined, and the axial profile, consisting of diameters along the axial direction, was obtained from the combined image. The X-ray imaging method could provide an accurate measurement with slope error of±19 μrad. Conclusions Applying X-ray imaging technique to determine the inner diameter of a mono-capillary optic can contribute to increasing fabrication accuracy of the mono-capillary optic through a feedback process between the fabrication and measurement of its diameter.

Primary leiomyosarcoma of the inferior vena cava (IVC) is a rare malignant tumor. Herein, we report the case of a 52-year-old male patient who had postprandial abdominal distension and right upper quadrant abdominal pain. The abdominal computed tomography (CT) angiogram showed an IVC mass extending from the infrahepatic to the suprarenal inferior vena cava. The radiologic findings were suggestive of an IVC leiomyosarcoma. Surgical resection and reconstruction with a cryopreserved homograft were performed. The follow-up abdominal CT angiogram revealed the patient to be disease-free 6 months after surgery with patency of the IVC and renal vein.

Lead telluride (PbTe) nanostructures were synthesized by galvanic displacement reaction of electrodeposited Co thin films where the effect of [Pb2+]/[HTeO2+] ratio in the electrolyte, the thickness of sacrificial layer, and the reaction time on the surface morphology and composition were systematically investigated. The composition of PbTe nanostructures were strongly dependent on the [Pb2+]/[HTeO2+] ratio in the electrolyte where the deposited contents were varied from Te-rich (i.e., Pb20Te80) to Pb-rich (i.e., Pb69Te31) PbTe. The surface morphologies varied from x-shaped, cucumber-like, and flower-like to dendrite structures. TEM analysis showed that x-shaped PbTe nanostructures grew in a single crystalline face-centered cubic (FCC) structure along the [100] and [110] directions.

Background: We evaluated the safety and efficacy of percutaneous extracorporeal membrane oxygenation (ECMO) in patients with primary graft dysfunction after heart transplantation. Methods: Of 65 patients (44 males and 21 females) who underwent heart transplantation from January 2006 to December 2012, 13 patients (group I) needed peripheral ECMO support due to difficulty in weaning from cardiopulmonary bypass (CPB) and 52 patients (group II) were weaned from CPB without mechanical support. The mean age of the patients at the time of operation was 54.4±13.6 years. There were no differences in the preoperative characteristics of the two groups. Multivariable analysis was performed to identify the risk factors for ECMO therapy. Results: All group I patients were successfully weaned from ECMO after 53±9 hours of circulatory support. Early mortality occurred in four patients (1 [7.7%] in group I and 3 [5.8%] in group II, p＞0.999). There were no differences in the postoperative complications between the two groups, with the exception of reoperation for bleeding. A greater number of group I patients underwent reoperation for bleeding (5 [38.5%] in group I vs. 6 [11.5%] in group II, p=0.035). In multivariable analysis, preoperative mechanical support (ECMO and intra-aortic balloon pump) and longer CPB time were the risk factors of ECMO therapy for graft dysfunction (odds ratio, 6.377; 95% confidence interval, 1.519 to 26.77; p=0.011 and odds ratio, 1.010; 95% confidence interval, 1.001 to 1.019; p=0.033). Conclusion: Percutaneous ECMO support could be a viable option for rescuing patients when graft dysfunction refractory to medical management develops after heart transplantation.

Permanent pacemaker implantation in small infants can be challenging because of patient size and expected somatic growth. In our case, we used the retrosternal space as a generator pocket for an extremely low-birth-weight premature baby with autoantibody-associated congenital heart block born to a systemic lupus erythematosus mother.

Doping is known as an effective way to modify both electrical and thermal transport properties of thermoelectric alloys to enhance their energy conversion efficiency. In this project, we report the effect of Pd doping on the electrical and thermal properties of n-type Cu0.008Bi2Te2.7Se0.3 alloys. Pd doping was found to increase the electrical conductivity along with the electron carrier concentration. As a result, the effective mass and power factors also increased upon the Pd doping. While the bipolar thermal conductivity was reduced with the Pd doping due to the increased carrier concentration, the contribution of Pd to point defect phonon scattering on the lattice thermal conductivity was found to be very small. Consequently, Pd doping resulted in an enhanced thermoelectric figure of merit, zT, at a high temperature, due to the enhanced power factor and the reduced bipolar thermal conductivity.

We fabricated organic photovoltaic (OPV) based on ZnO ripple structure on indium tin oxide as electroncollecting layers and PTB7-F20 as donor polymer. In addition, atomic layer deposition (ALD) was used for preparing additional ZnO layers on rippled ZnO. Addition of 2 nm-thick ALD-ZnO resulted in enhanced initial OPV performance and stability. Based on photoluminescence results, we suggest that ALD-ZnO layers reduced number of surface defect sites on ZnO, which can act as electron-hole recombination center of OPV, and increased resistance of ZnO towards surface defect formation.

For high-risk patients, endovascular aortic aneurysm repair (EVAR) is a good option but may lead to serious complications, which should be addressed immediately. A 75-year-old man with a history of abdominal surgery underwent EVAR for an aneurysm of the abdominal aorta and iliac arteries. During EVAR, iliac artery rupture and graft limb occlusion occurred, and they were successfully managed by the additional deployment of an iliac stent graft and balloon thrombectomy, respectively. We, herein, report a rare case of the simultaneous development of the two fatal complications treated by the endovascular technique.

Manipulating the surface characteristics of metal oxide electrodes allows the properties of the interface between electrodes and the electrolyte to be controlled and can lead to improvements in both efficiency and reliability of the electrodes. In this study, the facets exposed on the surfaces of Cu2O photoelectrodes were manipulated by controlling the pH of the bath during Cu2O film electrodeposition. The Cu2O film with (100)-type facets, deposited at a bath pH of 12, produced a photocurrent 19 times higher than that of the film deposited at pH 8.3 and possessing (111) facets. In addition, inverse-opal-structured Cu2O films were electrodeposited in alkali solutions using templates of polystyrene beads; these films exhibited even higher photocatalytic activities than the planar ones. The templated, three-dimensional (3D) Cu2O film deposited at pH 12 produced a photocurrent 2.14 times higher than that generated by the planar Cu2O film deposited at the same pH; this was a result of the greater surface area and higher light absorption of the 3D film.

The scalable, high-throughput, cost-effective synthesis of high-quality tetragonal tellurium (t-Te) nanowires by the galvanic displacement reaction of Si on a 4-in. Si wafer is demonstrated. This method does not require any heterogeneous seeds, physical templates, or surfactants. In addition, because seed nucleation and growth are both instantaneous, the synthesized nanowires had uniform lengths across the substrate. Furthermore, the effects of the deposition conditions, including the solution composition and reaction time and temperature, on the morphologies, dimensions, and crystallinities of the Te nanowires were analyzed to investigate the growth mechanism. The synthesized t-Te nanowires exhibited excellent piezoelectric properties, with the output current being as high as −75.0 nA.

Electrochemically deposited bismuth telluride (Bi x Te y ) thin films were grown from nitric acid baths on sputtered Au/Ni/Si substrates. The film compositions and morphology were strongly dependent on the deposition conditions. Surface morphologies varied from granular to needle-like structures depending on the Te content of the films. The power factor improved with the increase of Bi ions in electrolytes, and this may be due to the improvement of the crystal structure and no inclusion of excess Te phases. Annealing up to 200 °C in a reducing H 2 atmosphere did not improve the power factor due to the interdependence of the Seebeck coefficient and the electrical conductivity.

One-dimensional Tellurium (Te) nanostructures with controlled dimensions and morphologies have been synthesized by the galvanic displacement reaction (GDR) of electrodeposited nickel (Ni) thin films. The effects of sacrificial Ni microstructure and HTeO 2 + ion concentration on the resulting Te nanostructures were systematically investigated. The preferred crystal orientation of sacrificial Ni thin films was varied to synthesize Te nanostructures with various levels of distinctiveness. By adjusting the concentration of HTeO 2 + ions in the galvanic displacement electrolyte, well-aligned one-dimensional (1-D) Te nanostructures such as conical and hexagonal pillars were prepared where the diameter ranged from ∼70 to ∼900 nm and the length ranged from 1 to 3.6 μm.

Bi x Sb2−x Te3 films were electrodeposited potentiostatically from acidic nitric baths at room temperature by controlling the electrodeposition parameters (i.e., the applied potential). Nearly stoichiometric Bi x Sb2−x Te3 thin films were obtained at applied potentials between −0.10 and −0.15 V versus the saturated calomel electrode (SCE). The electrical and thermoelectric properties of the as-deposited films were degraded at more negative deposition potentials; this might be attributed to the greater defect density formed. The post-annealing process in the reducing environment improved the electrical and thermoelectric properties, possibly because of a decrease in antistructure defects.

Millimeter-long one-dimensional SbxTey nanoribbons with controlled composition and dimensions (down to 16 nm) were demonstrated using lithographically patterned electrodeposition at predetermined locations. The morphology of nanoribbons was tuned by applying a pulse plating technique and addition of surfactant (i.e., CTAB) in the electrolyte. Independent of geometry, the deposit Te content decreased from 69 to 51 at. % Te with an increase in the applied potential. The electrical resistivity and field effect hole mobility were strongly dependent on the composition of the nanoribbon where the lowest electrical resistivity (7.9 × 10–4 ohm m) with highest hole mobility (24.6 cm2/V s) was observed from the Sb2Te3 nanoribbon. The temperature-dependent electrical resistance measurement shows low-temperature phase transition behaviors in the temperatures between 333 and 351 K.

Organic photovoltaics (OPVs) consisting of ZnO ripple structures used as electron-collecting layer were fabricated without and with additional TiO 2 layers prepared by atomic layer deposition (ALD). We show that TiO 2 layer with a thickness of less than 1 nm can enhance OPV performance, since additional TiO 2 can heal surface defects of ZnO, which can act as recombination center of electron and hole created in the active layer by photon-absorption. In contrast, a thicker TiO 2 film (>2 nm) showed a lower OPV performance than that of bare sample without TiO 2 , most likely due to a lower conductivity of TiO 2 than that of ZnO. We show that precise control of oxide thin layer using ALD can be beneficial for fabricating high-performing OPV.

A facile electrochemical functionalization method was utilized to decorate single-walled carbon nanotubes (SWNTs) with tin oxide and their gas sensing performance toward various analytes (NH3, NO2, H-2, H2S, acetone, and water vapor) was evaluated at room temperature. Tin oxy-hydroxide was sitespecifically precipitated on the surface of SWNTs because of an increase in local pH during electrochemical reduction of nitrate to nitrite ions. By adjusting the amount of charge passed during deposition, the amount of tin oxide deposited on SWNTs was controlled, which altered the electronic and gas sensing properties of the nanostructures. The resulting hybrid nanostructures showed excellent sensitivities upon exposure to trace amounts of both oxidizing gases (limit of detection (LOD) of 25 ppbv for NO2) and reducing gases (LOD of 10 ppmv for H-2) at room temperature. The enhanced sensing performance was due to the charge transfer between the surface active tin oxide nanoparticles and SWNTs, with the direction of charge transfer depending on the analyte gas. This approach can be applied to fabricate other hybrid metal oxide-SWNTs nanostructures to create highly sensitive gas sensor arrays. (C) 2013 Elsevier Ltd. All rights reserved.

Background Recombinant human bone morphogenetic proteins (rhBMPs) have been widely used in regenerative therapies to promote bone formation. The production of rhBMPs using bacterial systems such as Escherichia coli (E. coli) is estimated to facilitate clinical applications by lowering the cost without compromising biological activity. In clinical practice, rhBMP-2 and osteoconductive carriers (e.g., hydroxyapatite [HA] and bovine bone xenograft) are used together. This study examined the effect of E. coli-derived rhBMP-2 combined with porous HA-based ceramics on calvarial defect in rabbits. Methods Six adult male New Zealand white rabbits were used in this study. The experimental groups were divided into the following 4 groups: untreated (NC), bovine bone graft (BO), porous HA (HA) and porous HA with rhBMP-2 (HA-BMP). Four transosseous defects of 8 mm in diameter were prepared using stainless steel trephine bur in the frontal and parietal bones. Histological and histomorphometric analyses at 4 weeks after surgery revealed significant new bone formation by porous HA alone. Results HA-BMP showed significantly higher degree of bone formation compared with BO and HA group (P

The shortage of available fresh water is one of the global issues presently faced by humanity. To determine a solution to this problem, the survival strategies of plants have been examined. In this study, a nature-inspired membrane with a highly charged surface is proposed as an effective membrane for the filtration of saline water. To mimic the desalination characteristics of mangrove roots, a macroporous membrane based on polyethylene terephthalate is treated with polyelectrolytes using a layer-by-layer deposition method. The fabricated membrane surface has a highly negative charged ζ-potential value of -97.5 ± 4.3 mV, similar to that of the first layer of mangrove roots. Desalination of saline water using this membrane shows a high salt retention rate of 96.5%. The highly charged surface of the membrane may induce a relatively thick and stable ion depletion zone in front of the membrane. As a result, most co-ions are repelled from the membrane surface, and counterions are also rejected by virtue of their electroneutrality. The water permeability is found to be 7.60-7.69 L/m

This paper describes an X-ray phase contrast imaging technique using analyzer-based optics called X-ray Dark-Field Imaging that has been under development for the past 10 years. We describe the theory behind XDFI, the X-ray optics required for implementing it in practice, and algorithms used for 2D, 2.5D, and 3D image reconstruction. The XDFI optical chain consists of an asymmetrically cut, Bragg-type monochromator-collimator that provides a planar monochromatic X-ray beam, a positioning stage for the specimens, a Laue-case angle analyzer, and one or two cameras to capture the dark and bright field images. We demonstrate the soft-tissue discrimination capabilities of XDFI by reconstructing images with absorption and phase contrast. By using a variety of specimens such as breast tissue with cancer, joints with articular cartilage, ex-vivo human eye specimen, and others, we show that refraction-based contrast derived from XDFI is more effective in characterizing anatomical features, articular pathology, and neoplastic disease than conventional absorption-based images. For example, XDFI of breast tissue can discriminate between the normal and diseased terminal duct lobular unit, and between invasive and in-situ cancer. The final section of this paper is devoted to potential future developments to enable clinical and histo-pathological applications of this technique.