Retina-Inspired Carbon Nitride-Based Photonic Synapses for Selective Detection of UV Light

Photonic synapses combine sensing and processing in a single device, so they are promising candidates to emulate visual perception of a biological retina. However, photonic synapses with wavelength selectivity, which is a key property for visual perception, have not been developed so far. Herein, organic photonic synapses that selectively detect UV rays and process various optical stimuli are presented. The photonic synapses use carbon nitride (C3N4) as an UV-responsive floating-gate layer in transistor geometry. C3N4 nanodots dominantly absorb UV light; this trait is the basis of UV selectivity in these photonic synapses. The presented devices consume only 18.06 fJ per synaptic event, which is comparable to the energy consumption of biological synapses. Furthermore, in situ modulation of exposure to UV light is demonstrated by integrating the devices with UV transmittance modulators. These smart systems can be further developed to combine detection and dose-calculation to determine how and when to decrease UV transmittance for preventive health care.

Effect of heat treatment and drawing on high-manganese steel pipe welded by gas tungsten arc

This study investigated the effect of post-weld processes including annealing and drawing on the microstructure and mechanical properties of high-Mn steel pipes welded by gas tungsten arc welding. The weld metal showed a solidified microstructure having coarse and elongated grains due to coalescence of columnar dendrite into welding heat direction. After post-annealing, the solidified microstructure changed into equiaxed grains due to recrystallization and grain growth. Mn segregation occurred during welding solidification and caused lower stacking fault energy (SFE) in the Mn-depleted region. Although epsilon-martensite formation in the as-welded state and during deformation was expected due to decreased SFE of the Mn-depleted zone, all regions showed a fully austenitic phase. The annealing process decreased strength due to grain coarsening but increased ductility. The drawing process increased strength of weld metal through work hardening. All pipes showed decreasing strain rate sensitivity (SRS) with deformation and negative SRS after certain strain levels. It was confirmed that negative SRS is related to less formation of mechanical twinning at a higher strain rate. This work provides fundamental insights into manufacturing a high-Mn steel pipe and manipulating its properties with annealing and drawing processes

A Box-Model Simulation of the Formation of Inorganic Ionic Particulate Species and Their Air Quality Implications in Republic of Korea

Abstract The Observation-Constrained Atmospheric BOX model (OCABOX) was used to analyze the formation of secondary inorganic PM species in the Seoul Metropolitan Area (SMA), South Korea. The measurement data of the ionic components of PM2.5 and their gaseous precursors made at the Olympic Park ground site (37.53°N, 127.12°E) during the Korea-United States Air Quality field campaign were used to run OCABOX in observation-based mode and compare the simulation results. The use of the HNO3 concentrations measured at a marine background site as the boundary conditions appeared to increase the accuracy of the model prediction of HNO3 and particulate NO3− concentrations. For the primary precursors emitted considerably throughout the SMA, such as NOx and NH3, using the data measured inside the SMA as the boundary conditions could lead to more accurate predictions. OCABOX was shown to be a reliable tool to analyze the formation of secondary inorganic aerosol in the SMA if used with appropriate regional background concentrations and observation-based constraint

Harald Szeemann : Individual Methodology

"Harald Szeemann (1933–2005) is without doubt one of the most authoritative figures of contemporary curatorial practice. He has played a considerable role in the development of exhibition curating since the 1960s, and almost all art-historical books refer to "When attitudes become form" (1969). Neither a biography nor a compilation of his projects, this publication, thanks to privileged access to the archives of the “Fabbrica rosa,” hopes to shed light on Szeemann’s curatorial methodology. Presenting numerous previously unpublished documents as well as interviews with the close collaborators of this “exhibition maker,” as he often referred to himself, the authors explore the structures and tools of his trade (his archives and his Agency, in particular), which allowed his practice to develop, and focus on two manifestations, realized 25 years apart, documenta 5 (1972) and "L’Autre" (1997). Exploring the historical context, two essays from historians Hal Foster and Jean-Marc Poinsot, revisit the principle historical debates of the period in question" -- p. [4] of cover

Microstructure and Mechanical Properties of Gas Tungsten Arc Welded High Manganese Steel Sheet

This study investigated microstructure and mechanical properties of high manganese steel sheet fabricated by gas tungsten arc welding (GTAW). The weld zone showed longitudinal coarse grains due to the coalescence of columnar dendrites grown into the direction of heat source, and the HAZ showed equiaxed coarser grains than the base metal due to the thermal effect of GTAW process. Mn segregation occurred in the inter-dendritic regions of the weld zone and Mn depletion thus occurred in the weld matrix. Although the stacking fault energy is expected to be lowered due to the Mn depletion, no noticeable change in the initial phase and deformation mechanism was found in the weld matrix. Lower hardness and strength were shown in the weld zone than the base metal, which was caused by the coarser grain size. The negative strain rate sensitivity observed in the weld zone and the base metal is considered to have originated from the negative strain rate dependency of twinning nucleation stress

Computed tomography volumetric analysis for predicting postoperative lung function for segmentectomy

OBJECTIVES: We compared the computed tomographic (CT) volumetric analysis and anatomical segment counting (ASC) for predicting postoperative forced expiratory volume in 1 s (FEV1) and diffusing capacity for carbon monoxide (D-LCO) in patients who had segmentectomy for early-stage lung cancer. METHODS: A total of 175 patients who had segmentectomy for lung cancer and had postoperative pulmonary function test were included. CT volumetric analysis was performed by software, which could measure total lung and target segment volume from CT images. ASC and CT volumetric analysis were used to determine predicted postoperative (PPO) values and the concordance and difference of these values were assessed. The relationship between PPO values and actual postoperative values was also investigated. RESULTS: The PPO-FEV1 and PPO-D-LCO showed high concordance between 2 methods (concordance correlation coefficient = 0.96 for PPO-FEV1 and 0.95 for PPO-D-LCO). There was no significant difference between PPO values as determined by 2 methods (P = 0.53 for PPO-FEV1, P = 0.25 for PPO-D-LCO) and actual postoperative values [P = 0.77 (ASC versus actual) and P = 0.20 (CT versus actual) for FEV1; P = 0.41 (ASC versus actual) and P = 0.80 (CT versus actual) for D-LCO]. We subdivided the patients according to poor pulmonary function test, the number of resected segments and the location of the resected lobe. All subgroup analyses revealed no significant difference between PPO values and actual postoperative values. CONCLUSIONS: Both CT volumetric analysis and ASC showed high predictability for actual postoperative FEV1 and D-LCO in segmentectomy.N