Edge Location Research Articles

Automatic thrust/fault and edge location with gravity data across the Shillong plateau and Mikir hill complex in northeastern India using the most positive and most negative curvature interpretation

Abstract Northeast India encompasses numerous thrusts, faults, and lineaments with undulated surface topography and is one of the utmost tectonically active regions in the world. Owing to the results of the collision of the Indian Plate under the Tibetan Plate and Burmese Plate, respectively, this area has affected the highest seismic potential zone-V, triggering many earthquakes. The current study area is located in and around the Shillong plateau, Mikir Hills, Naga Hills, Arakan-Yoma fold belt, Bengal basin, and Mishmi hills of the Himalayan foothills and that fall under the northeast of India. The thrusts and faults information available in this area are very scanty due to limited availability of geoscientific data and revealing seismic survey. Henceforth, it is necessary to get enhanced geoscientific learning for a better understanding of thrusts, faults, and lineaments information, the most positive and most negative curvature attribute analyses have been carried out using ground gravity data in this area. The significant derived results from this study encourage supplementary findings of thrust, fault, and lineament information, which also correlate well with the previously found results of 3D Euler deconvolution and source edge detection. Although, gravity data interpretation has its own limitations, however, the current derived results using the latest curvature analysis approach utilizing gravity data show realistic invigorated solutions for a better understanding of the thrust, fault, and lineament locations in this area.

Effect of MoS2 and electrolyte temperature on the electrochemical performance of NiCoS@rGO-based electrode material for energy storage, oxygen reduction reaction and electrochemical glucose sensor

Two-dimensional transition metal dichalcogenides (2D-TMDs) are essential in energy storage devices. MoS2/rGO nanostructures have improved energy storage capacity because of their layered shape, proximity effect, inherent broad surface area, and edge locations. Herein, we have synthesized NiCoS@MoS2@rGO composite electrode material for supercapattery energy storage devices and electrochemical glucose sensors via the hydrothermal method. The electrochemical performance of NiCoS, NiCoS@MoS2 and NiCoS@MoS2@rGO were first investigated in three electrode assemblies at different electrolyte temperatures (27 °C to 50 °C). Among all the samples, NiCoS@MoS2@rGO shows the superior value of Qs (1138C/g or 1896.66 F/g) with 1 M KOH electrolyte solution at 50 °C. The asymmetric NiCoS@MoS2@rGO//AC device showed a high specific capacity (301C/g, at 1 A/g), energy and power densities of 65.44 (Wh/Kg), and 1267.18 (W/Kg), respectively. A significant value of Coulombic efficiency of 92.79 % and capacity retention of 83.42 % was acquired after 5000 galvanostatic charging/discharging (GCD) cycles. Further, the NiCoS@MoS2@rGO nanocomposite electrode material is used for oxygen reduction reaction activity. The initial potential for the oxygen reduction was 0.67 V vs. RHE, and the electrode showed high stability. Besides, the hybrid device is used as an electrochemical glucose sensor to detect glucose with a highly precise detection response. This research will open new ideas for developing more efficient TMDs sulfide-based nanocomposite materials for future energy storage systems and biomedical applications.

Conductive filament distribution in nano-scale electrochemical metallization cells.

We report a combined experimental and theoretical study of the spatial distributions and sizes of conductive filaments in nano-scale electrochemical metallization (ECM) cells. Each cell comprises a silver nanocube as active electrode, a titanium dioxide (TiO2) or aluminum oxide (Al2O3) layer as dielectric, and a highly-doped silicon substrate as passive counter electrode. Following electroforming of the ECM cell and subsequent mechanical delamination of the silver nanocubes, current maps at previous particle locations reveal an intriguing metal distribution in the TiO2, with preferential accumulation close to the original locations of the nanocube edges. We assign this behavior to electric field enhancements close to the cube edge positions. In contrast, filaments in Al2O3 layers show a comparatively homogenous distribution, which may be assigned to its lower dielectric permittivity. By increasing the oxide thickness, the total area of conductive spots in the current maps increases monotonically for both materials. Kinetic Monte-Carlo simulations of ion migration dynamics in TiO2 confirm the experimental observations, describing both the preferred locations and oxide thickness-dependent metal loadings associated with filament formation. Overall, our findings are highly valuable for the design of future electrochemical metallization cells, especially in the sub-100 nm regime, where optimal filament control is of major importance for achieving lowest device-to-device variability.

The clinical characteristics and outcomes of the patients with pyogenic granuloma: A retrospective study of 144 patients

Aim: Pyogenic granuloma (PG), also known as lobular capillary hemangioma, is a benign, reactive vascular tumor. We aimed to evaluate the demographic and clinical characteristics, treatments received, and outcomes of patients followed up at our clinic with PG. Materials and Methods: We retrospectively evaluated all patients followed up at our clinic with PG in the last 4 years. Results: A total of 144 patients were included in our study. 73 (51%) of the patients were female and 71 (49%) were male. The mean age of the patients was 31.3±8.3 years. When we examined the PG locations in our patients, we observed that it was most commonly found in the arm/hand area (40%), on the face (29%), foot/leg area (19%), and on the trunk (8.3%). The highest number of lesions were respectively in the hand, foot nail edge, and lip locations. Out of the patients where the lesion side was specified, 63 had the lesion on the left while 20 had it on the right (p=0.001). 51% of our patients underwent excisional surgery. Other treatments applied to our patients, in order, were cryotherapy (15.3%), electrocauterization (8.3%), cauterization with silver nitrate, cryotherapy+electrocauterization, topical antibiotic and cryotherapy+timolol drop. When evaluating the outcomes of the patients, we learned from the notes dropped into the system at later controls that 73% had recovered. The remaining patients were lost to follow-up. When comparing the features of patients who were treated with non-excisional methods to those who underwent excision, we observed that there was a higher rate of patients younger than 12 years (p=0.023), a higher incidence of foot nail edge (p=0.016) and lip location (p=0.048), and a higher frequency of pregnancy in this group. Conclusion: PG is a vascular tumor of importance due to its potential for bleeding and ulceration and its chronic course if left untreated. Since there are malignant lesions in its differential diagnosis, we believe that surgical excision is a more appropriate treatment option when feasible. We think that the data we have obtained needs to be supported by more comprehensive, broader, and prospective studies.

Failure mechanism and damage tolerance of turnout point rail in high-speed railway

The failure of point rail occurred during the turnout service in the China Railway. The failure analysis was conducted using experimental and simulation methods, indicating that the combination of knife edge and stress concentration in the drive support was responsible for the crack initiation in the drive support of the point rail. Furthermore, the effects of the edge depth and location on the fatigue crack propagation of the drive support in the turnout point rail were investigated. The fatigue life for the turnout with knife edges is 10 %–20 % of that without knife edges. The crack propagation rate on the point rail drive support increased sharply with the increase of the edge depth. The crack propagation rate also increased with edge proximity to stress concentration point. Meanwhile, the damage tolerance of the point rail was defined based on the result that the fatigue life before the crack size 10 mm accounted for 84.4 % of the whole fatigue life.

Analytic study of exposure contrast over feature edge in electron-beam lithography

In electron-beam (e-beam) lithography, the location of a feature edge may vary with experiment due to the stochastic nature of the e-beam exposure and resist-development processes. From the viewpoint of consistent reproducibility of a circuit pattern, it is essential to enhance the stability of a feature edge in the e-beam lithographic process. A fundamental metric affecting the stability is the exposure contrast over the feature edge, and therefore, it is important to understand the dependency of exposure contrast on significant parameters. However, the computer simulation for the dependency analysis is time-consuming and needs to be repeated. In this study, a new method has been developed by deriving closed-form mathematical expressions of exposure contrast for the cases of a single feature and a uniform pattern of multiple features. The mathematical expressions enable the fast analysis of exposure contrast without simulation, and therefore, can serve as a useful tool in e-beam lithography.

Perception-guided defocus blur detection based on SVD feature

Defocus blur detection aims to identify out-of-focus regions in a single image. Although defocus blur detection has attracted more and more attention in recent years, it still faces some challenges. In particular, the in-focus regions with low contrast are easily misidentified as out-of-focus regions. To address this problem, a perception-guided defocus blur detection method is proposed to estimate defocus blur amounts at edge locations from a single image based on the singular value decomposition (SVD) features. Inspired by the fact that blurring the clear region produces significant changes in SVD domain as compared with re-blurring the blurred one, new SVD features are extracted based on re-blurred singular value difference (RESVD) of the corresponding local gradient patches. Then, perceptual weight based on Just Noticeable Blur (JNB) is introduced to guide the sparse blur map estimation obtained with the SVD features. Finally, the full defocus blur map is constructed from the sparse defocus blur map by the Matting Laplace algorithm. Visual evaluations are conducted on the CUHK, DUT and CTCUG datasets, employing mean absolute error (MAE) and Fβ-measure as quantitative evaluation metrics. The experimental results demonstrate that the proposed defocus blur detection method is superior to 13 state-of-the-art methods. On the DUT dataset, the proposed method yields a high Fβ-measure (0.802) with a low MAE (0.081) compared to other methods (Fβ≤0.799, MAE ≥0.099). On the CUHK and CTCUG datasets, our method achieves the best balance between Fβ-measure and MAE. Furthermore, our method results in better visual effects than other methods regarding realism and quality.

Growth characteristics and wear properties of micro-arc oxidation coating on Ti-6Al-4V with different laser texture shapes

Poor wear properties severely limit the field of application and service life of titanium alloys. Three kinds of textures (dimple, groove and mesh) were prepared by laser texturing technique and compounded with micro-arc oxidation treatment to improve the tribological properties of titanium alloys in this study. The coatings' morphology, structure, and composition were characterized, and their antiwear properties were analyzed. The results show that the proportion of rutile phase in the coating increases with increasing textured area rate and that the textured edge coating has higher Si and P content, with increased thickness and densities. In terms of friction properties, the dimpled texture shows the best friction properties when textured alone, with a 28.6 % decrease in the average coefficient of friction compared to the substrate; in contrast, the meshed texture shows the best friction properties after the micro-arc oxidation treatment, with a 76.2 % decrease in the average coefficient of friction compared to the substrate. Studies have shown that laser texturing can reduce wear by retaining abrasive debris. However, laser texturing alone does not provide a significant increase in hardness at the edge location, which is more susceptible to damage during wear, leading to more severe wear. The “tip effect” encourages the growth of a micro-arc oxide layer, and the resulting hardness of the layer helps protect the texture structure from damage. The synergistic effect of the texture and the rough, hard structural features of the coating itself enhances the wear resistance of the composite coating.

BiVO4 Heterojunctions as Efficient Photoanodes for Photoelectrochemical Water Oxidation

AbstractPhotoelectrochemical (PEC) water splitting has attracted strong interest as sustainable technology by converting solar energy into hydrogen. The semiconductor photoelectrodes play an important role to increase the solar‐to‐hydrogen conversion efficiency. Bismuth vanadate (BiVO4) is an excellent candidate as a photoanode material for PEC water oxidation because of its visible light absorption, suitable band edge location, high stability and low cost. However, BiVO4 alone may undergo short carrier diffusion length, rapid recombination of photo‐induced charge carriers and photocorrosion. The heterojunction strategy established by combining two or more materials has provided an outstanding technique to address these issues. This Review focuses on recent important works with respect to BiVO4 heterojunction photoanodes for PEC water oxidation reactions, including interface junction and surface functional junction formation. Additionally, challenges faced and prospects for future research on BiVO4 heterojunction photoanodes in the field of solar‐to‐hydrogen conversion are proposed.

Multifunctional MnFe2O4/TiO2/Ti3C2Tx composites based on in-situ grown TiO2 for efficient microwave absorption, high hydrophobicity, and heat dissipation properties

Despite the fact that the 2D structure Ti3C2Tx with abundant defects and functional groups contributes to the high microwave absorption (MA) performance, it is difficulty to improve the strength and bandwidth by pursuing higher conductivity or loading more groups due to the limitation of intrinsic properties. Therefore, it is important to ingeniously design efficient Ti3C2Tx based MA composites assembling the features of abundant surface groups, good dispersibility, multiple composition, and precise structure. Inspired by the fact that Ti3C2Tx contains thermodynamically metastable marginal Ti atoms, TiO2 nanoparticles can be grown in-situ on Ti3C2Tx nanosheets uniformly and increase the spacing of Ti3C2Tx layers, and then MnFe2O4 nanoparticles are introduced into the layers of Ti3C2Tx by electrostatic self-assembly method for optimized impedance matching. This designed hierarchical MnFe2O4/TiO2/Ti3C2Tx composites shows excellent MA performance, and the minimum reflection loss (RLmin) reaches −46.91 dB with a thickness of 2.5 mm at frequency of 10.4 GHz. The high MA performance mainly comes from the enhanced interfacial polarization induced by edges location and interface region among TiO2, MnFe2O4, and Ti3C2Tx. In addition, the conduction loss existed in the interior untreated Ti3C2Tx, the dielectric loss generated by multiple composition, the multiple scattering from improved large surface specific area all contribute to the excellent MA performance. Meanwhile, the simple preparation process and good stability storage at room temperature under air atmosphere of the MnFe2O4/TiO2/Ti3C2Tx composites promote its exploration on practical use, and the lab-gown cloth coated with MnFe2O4/TiO2/Ti3C2Tx composites shows better electromagnetic shielding properties, hydrophobicity, and heat transfer ability than pure fabric, showing the potential for practical application.

Rapid laminated clastic alluviation associated with increased Little Ice Age flooding co-driven by climate variability and historic land-use in the middle Severn catchment, UK

The analysis of exceptionally well-preserved visible clastic laminations in deep alluvial sediments at Kempsey, Worcestershire (UK), allows a new high-resolution analysis of late-Holocene flood-history in the largest UK catchment, as well as local human response. At the sample site over 4.5 m of sandy-silt overbank-alluvium accumulated on the floodplain and optically stimulated luminescence (OSL) dating of the upper 2.25 m demonstrates accretion from the late 14th century CE onwards. Sub-centimetre to centimetre resolution multi-proxy sediment analysis (loss on ignition, magnetic susceptibility, particle size, ITRAX and portable XRF) demonstrate clear variations in depositional history over the last millennium due to channel stability. Between c. 1380 and 1550 CE overbank sedimentation was driven by lower energy flood events, with negligible effect from climatic conditions during the Spörer Minimum (1460–1550 CE). After c. 1550 CE the magnitude of flooding events increased and by c. 1610 CE, the start of the visible sub-centimetre laminations, the accumulation rate regularly exceeded 3 mm year−1, which increased to 4.5 mm year−1 between c. 1690 and 1710 CE, and 3 and 3.5 mm year−1 between c. 1790 and 1840 CE before alluviation was altered by an embankment. The greatest extent of coarse overbank deposition and increased accumulation rate occur concurrently with periods of climatic instability associated with the Maunder (1645–1715 CE) and Dalton (1790–1820 CE) Minima, the periods of largest historical floods and during the intensification of arable cultivation across the middle Severn catchment. This data correlates well with other sites in the catchment suggesting that these are basin-wide forcing-responses. We also present evidence that this catchment-wide hydro-geomorphological history had local effects in shifting the geographical focus of an important settlement away from its historic floodplain edge location – which can be viewed as an adaptation to the flood risk.

Real-Time Belt Deviation Detection Method Based on Depth Edge Feature and Gradient Constraint.

Aiming at the problems of the poor recognition effect and low recognition rate of the existing methods in the process of belt deviation detection, this paper proposes a real-time belt deviation detection method. Firstly, ResNet18 combined with the attention mechanism module is used as a feature extraction network to enhance the features in the belt edge region and suppress the features in other regions. Then, the extracted features are used to predict the approximate locations of the belt edges using a classifier based on the contextual information on the fully connected layer. Next, the improved gradient equation is used as a structural loss in the model training stage to make the model prediction value closer to the target value. Then, the authors of this paper use the least squares method to fit the set of detected belt edge line points to obtain the accurate belt edge straight line. Finally, the deviation threshold is set according to the requirements of the safety production code, and the fitting results are compared with the threshold to achieve the belt deviation detection. Comparisons are made with four other methods: ultrafast structure-aware deep lane detection, end-to-end wireframe parsing, LSD, and the Hough transform. The results show that the proposed method is the fastest at 41 frames/sec; the accuracy is improved by 0.4%, 13.9%, 45.9%, and 78.8% compared to the other four methods; and the F1-score index is improved by 0.3%, 10.2%, 32.6%, and 72%, respectively, which meets the requirements of practical engineering applications. The proposed method can be used for intelligent monitoring and control in coal mines, logistics and transport industries, and other scenarios requiring belt transport.

From waste to wealth: Using MgO nanoparticles to transform ammonium into a valuable resource

In this contribution, a versatile approach to the crystallization of ammonium carnallite is discussed through a highly efficient process of ammonium removal from an aqueous solution on MgO(111) surface through a rapid one-pot route. In addition to effective ammonium removal from the reaction environment and recovering it in the form of ammonium carnallite, another dual-purpose application of this approach is the recovery of magnesium in the form of carnallite crystals as a valuable metal with wide application in the industry. The MgO nanoparticles (MgO-NPs) showed high adsorption potential due to the presence of high index surfaces of (111) in the nanoparticle lattice due to the unsaturated valley and edge locations. The phase purity and crystallinity of MgO-NPs were investigated by XRD, and the planes' lattice was confirmed using SAED patterns, and lattice fringes from HRTEM images, while their acidic active sites led to high NH4+ removal using NH3-TPD analysis. A mechanism of ammonium adsorption on the active sites of the MgO(111) surface is proposed for the crystallization phenomenon. FESEM, EDS, HRTEM, XRD, FTIR, and BET analyses were evaluated to confirm the synthesis of single-crystal carnallite. Subsequently, TGA tests displayed the ammonium carnallite weight loss through decomposition to NH3 and HCl and proved the formation of MgO. Therefore, the high recovery rate of 100 mg/L ammonium within 30 min at neutral pH with 125 mg/L of MgO-NPs through the adsorption/crystallization process was revealed. Ammonium recovery from wastewater reduces the costs, energy, and environmental footprints associated with its removal processes.

Underwater Fish Segmentation Algorithm Based on Improved PSPNet Network.

With the sustainable development of intelligent fisheries, accurate underwater fish segmentation is a key step toward intelligently obtaining fish morphology data. However, the blurred, distorted and low-contrast features of fish images in underwater scenes affect the improvement in fish segmentation accuracy. To solve these problems, this paper proposes a method of underwater fish segmentation based on an improved PSPNet network (IST-PSPNet). First, in the feature extraction stage, to fully perceive features and context information of different scales, we propose an iterative attention feature fusion mechanism, which realizes the depth mining of fish features of different scales and the full perception of context information. Then, a SoftPool pooling method based on fast index weighted activation is used to reduce the numbers of parameters and computations while retaining more feature information, which improves segmentation accuracy and efficiency. Finally, a triad attention mechanism module, triplet attention (TA), is added to the different scale features in the golden tower pool module so that the space attention can focus more on the specific position of the fish body features in the channel through cross-dimensional interaction to suppress the fuzzy distortion caused by background interference in underwater scenes. Additionally, the parameter-sharing strategy is used in this process to make different scale features share the same learning weight parameters and further reduce the numbers of parameters and calculations. The experimental results show that the method presented in this paper yielded better results for the DeepFish underwater fish image dataset than other methods, with 91.56% for the Miou, 46.68 M for Params and 40.27 G for GFLOPS. In the underwater fish segmentation task, the method improved the segmentation accuracy of fish with similar colors and water quality backgrounds, improved fuzziness and small size and made the edge location of fish clearer.

Brief windows with more favorable atmospheric conditions explain patterns of Polylepis reticulata tree water use in a high-altitude Andean forest.

Polylepis trees occur throughout the Andean mountain region, and it is the tree genus that grows at the highest elevation worldwide. In the humid Andes where moisture is rarely limiting, Polylepis trees must adapt to extreme environmental conditions, especially rapid fluctuations in temperature, ultraviolet radiation and vapor pressure deficit (VPD). However, Polylepis' water-use patterns remain largely unknown despite the importance of understanding their response to microclimate variation to determine their capacity to maintain resilience under future environmental change. We conducted a study in a Polylepis reticulata Kunth forest in the Ecuadorian Andes to evaluate its tree water-use dynamics and to identify the main environmental drivers of transpiration. Tree sap flow was monitored simultaneously with soil volumetric water content (VWC) and microclimate during 2 years for trees growing in forest edge and interior locations. We found that sap flow was primarily controlled by VPD and that VWC exerted a secondary role in driving sap flow dynamics. The highest values for sap flow rates were found when VPD>0.15kPa and VCW<0.73cm3cm-3, but these threshold conditions only occurred during brief periods of time and were only found in 11% of our measurements. Moreover, these brief windows of more favorable conditions occurred more frequently in forest edge compared with forest interior locations, resulting in edge trees maintaining 46% higher sap flow compared with interior trees. Our results also suggest that P. reticulata has a low stomatal control of transpiration, as the sap flow did not decline with increasing VPD. This research provides valuable information about the potential impacts of projected future increases in VPD due to climate change on P. reticulata water-use dynamics, which include higher sap flow rates leading to greater transpirational water loss due to this species' poor stomatal control.

(Invited) Understanding Photoelectrocatalysis on Epitaxial Oxide Surfaces

The intermittent nature of renewable energy sources requires a clean, scalable means of converting and storing energy. One Earth abundant storage option is water electrolysis, storing energy in the bonds of O2 and H2. Photoelectrochemical (PEC) cells based on semiconductor/liquid interfaces can convert sunlight to chemical fuels without external circuitry, such as “splitting” water into O2 and H2 upon illumination. The efficacy of conversion depends in part on the location of the semiconductor band edges, dictating absorption, and also the rectifying properties of semiconductor–electrolyte junctions, which drives the separation of electron–hole pairs.We will present studies of model oxide La(1-x)SrxFeO3 photoelectrodes grown by molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) that display a known crystallographic orientation, surface area, path for charge transport, and strain. Aliovalent doping can tune the transition metal redox properties as well as the material band gap and conductivity, resulting in a rich phase space of possible water-oxidation photoanodes. Comparing the photooxidation of a fast redox couple to the slugging water oxidation reaction demonstrates the potential of electronic states that must be filled prior to oxygen evolution. Measurements of the surface speciation in a humid environment demonstrate that Sr incorporation also promotes hydroxylation, suggesting that water oxidation proceeds through the oxidation of FeIII-OH states, which is facilitated by Sr incorporation and results in an increased photovoltage. Surface-sensitive measurement of the valence band and unoccupied states (via O K-edge X-ray absorption spectroscopy) under humid conditions further support this picture. This fundamental insight builds understanding necessary for the design of active, earth-abundant photocatalysts that can be integrated into PEC devices for efficient conversion of solar energy into chemical fuels.

Reversible Redox Probes to Determine the Band Edge Locations for Nano-TiO2

Semiconductor (photo-)electrocatalysts show immense promise in answering the difficulties faced in CO2 electrolysis in relation to the reduction product selectivity. We thus see materials like ZnO[1], Cu2-xSe[2], MoS2 [3], TiO2 [4] and their numerous composites being frequently investigated for their catalytic properties in CO2 (photo-)electroreduction. These catalysts are fabricated via varying techniques and can assume very different thicknesses and morphologies. Although the nano-semiconductors may behave differently, often only the bulk properties are considered when proposing possible reaction pathways. Determining band edge locations of semiconductors in solutions is one such case, where Mott-Schottky (MS) measurements are a widely accepted strategy. The measurement of the potential dependence of the capacitance of the semiconductor space-charge layer under depletion indeed forms an elegant method to determine the flat-band potential and hence the band edge positions for bulk semiconductors in solution. However, the MS method cannot be used for nano-structured semiconductor electrodes in the form of thin films, nanorods or nanoparticles coated on conducting substrates, as their nano-dimensions are typically much smaller than that of a semiconductor depletion layer.In this work, we explored an alternate strategy to determine band edge positions of nano-semiconductors using reversible redox probes. A model thin film system comprised of 30nm anatase TiO2 is used to demonstrate the feasibility of the strategy in aqueous electrolyte solutions. Fe, Ru and Cr based reversible redox species were used as electrochemical probes in cyclic voltammetry experiments with varying solution pH. Based on the presence/absence of the reversible behavior of these probes, we can deduce the TiO2 band edge locations. The procedure also allows us to draw parallels between semiconductor-metal and semiconductor-solution interfaces to gain new insights into the CO2 reduction mechanism on such semiconductor electrodes. Figure 1

Accurate subvoxel location and characterization of edges in 3D images based on the Partial Volume Effect

An accurate estimation of the position, orientation, principal curvatures, and change in intensity of the edges in a 3D image provides highly useful information for many applications. The use of derivative operators to compute the gradient vector and the Hessian matrix in each voxel usually generates inaccurate results. This paper presents a new edge detector which is derived from the Partial Volume Effect (PVE). Instead of assuming continuity in the image values, edge features are extracted from the distribution of intensities within a neighborhood of each edge voxel. First, the influence of the intensities of the voxels in first- and second-order edges is analyzed to demonstrate that these types of edges can be precisely characterized from the intensity distribution. Afterward, this approach is extended to especially demanding situations by considering how adverse conditions can be tackled. This extension includes filtering noisy images, characterizing edges in blurred regions, and using windows with floating limits for close edges. The proposed technique has been tested on synthetic and real images, including some particularly difficult objects, and achieving a highly accurate subvoxel characterization of the edges. An open source implementation of our method is provided.

Atomic-level investigation on significance of photoreduced Pt nanoparticles over g-C3 N4 /bimetallic oxide composites.

Designing an effective photocatalyst for solar-to-chemical fuel conversion presents significant challenges. Herein, g-C3 N4 nanotubes/CuCo2 O4 (CN-NT-CCO) composites decorated with platinum nanoparticles (Pt NPs) were successfully synthesized by chemical and photochemical reductions. The size distribution and location of Pt NPs on the surface of CN-NT-CCO composites were directly observed by TEM. Extended X-ray absorption fine structure (EXAFS) spectra of Pt L3-edge for the above composite confirmed establishment of Pt-N bonds at an atomic distance of 2.09 Å in the photoreduced Pt-bearing composite, which was shorter than in chemically reduced Pt-bearing composites. This proved the stronger interaction of photoreduced Pt NPs with the CN-NT-CCO composite than chemical reduced one. The H2 evolution performance of the photoreduced (PR) Pt@CN-NT-CCO (2079 μmol h-1 g-1 ) was greater than that of the chemically reduced (CR) Pt@CN-NT-CCO composite (1481 μmol h-1 g-1 ). The abundance of catalytically active sites and transfer of electrons from CN-NT to the Pt NPs to participate in the hydrogen evolution are the primary reasons for the improved performance. Furthermore, electrochemical investigations and band edge locations validated the presence of a Z-scheme heterojunction at the Pt@CN-NT-CCO interface. This work offers unique perspectives on the structure and interface design at the atomic level to fabricate high-performance heterojunction photocatalysts.

Thoracoscopic approach as surgical management of esophageal epiphrenic diverticulum.

Management of diverticulum of the lower esophagus or epiphrenic diverticulum can be performed using the abdominal or thoracic approach. In some cases, the thoracic approach is preferred, but few studies have described thoracoscopic resection. The objective of the present study was to investigate the thoracoscopic approach for management of epiphrenic esophageal diverticulum. From 2008 to 2018, all patients undergoing surgery for epiphrenic esophageal diverticulum by the thoracoscopic approach were included in this single-center, retrospective, observational study. Data on diverticulum, surgery and follow-up were assessed. During the study period, 14 patients underwent surgery. Two patients had two diverticula. The mean location of the superior edge of the diverticulum was 7cm (2-14cm) above the gastro-esophageal junction. The mean size of the diverticulum was 39 millimeters (20-60). Thoracoscopic approach was used in all patients. No conversion to thoracotomy was required. Mean operative time was 168min (120-240). No postoperative mortality occurred. The overall complication rate was 40% (6 complications out of 15 resections), with three major complications including leaks (n=2) and a case of bronchoesophageal fistula (n=1). Median length of hospital stay was 12 days (8-40). At a mean postoperative follow-up of 20.7 months (5-71), 85% of patients had complete disappearance of preoperative symptoms without recurrence of the diverticulum on the barium swallow study test. Thoracoscopic approach as management of epiphrenic diverticulum is feasible, with acceptable short-term morbidity. The thoracoscopic approach is also effective in resolving preoperative symptoms.