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Herein, we systematically explored how to tailor heterogeneity in the Ni-Nb-(Y, Gd) phase-separated metallic glasses (PSMGs) by carefully constructing a metastable miscibility gap and investigating its effect on the formation of heterogeneous shear band (SB) nucleation sites. The Ni60Nb40-x(Y, Gd)x PSMGs with either Nb-Y or Nb-Gd atomic pair (ΔHmix=+30 kJ/mol) showed hierarchically phase-separated microstructures at the nanoscale, which can be interpreted based on a metastable miscibility gap. Interestingly, statistical analysis of the initiation of plastic deformation via nanoindentation first pop-in analysis in these PSMGs reveals a unique trimodal distribution, unlike the bimodal distribution in monolithic MGs. This tendency arises from the formation of nanoscale phase boundaries as additional differentiated heterogeneous SB nucleation sites. The homogenously dispersed SB nucleation sites help hinder strain localization and SB propagation. In particular, a PSMG with a nanoscale interconnected structure exhibits homogeneous-like plastic deformation, where neither obvious pop-ins nor distinct surface shear steps are observed in the (nano-)indentation test. We believe this study's results provide an effective guideline for tuning correlative heterogeneity and related mechanical responses in PSMGs, highlighting the importance of tailoring microstructure even in MGs.

Recent advancements have significantly improved the field of segmentation-based change detection, particularly in the context of remote-sensing images. However, change detection datasets generally lack segmentation annotations, and the required labeling process is resource-intensive. We propose an improved change detection method based on segmentation to address this challenge. First, change detection annotations are converted to incomplete segmentation annotations through label matching. During segmentation, we utilize the focused information-guided segmentation method (FIGS) and a greenness index to provide prior information during training, guiding the model using accurately labeled regions. Finally, we generate a change map using pretrained features obtained from the segmentation stage. We demonstrate the robustness of our proposed label-matching process by comparing the results to a correctly matched dataset and show that incorporating FIGS and the greenness index improves the segmentation performance. Our method achieves effective change detection results even in scenarios associated with a shortage of annotations.

Radiometric calibration has become important pre-processing with increasing use of unmanned aerial vehicle (UAV) images in various applications. In order to convert the digital number (DN) to reflectance, vicarious radiometric calibration is widely used including relative radiometric calibration. Some UAV sensor systems can measure irradiance for precise relative radiometric calibration. However, most of UAV sensor systems cannot measure irradiance and therefore precise relative radiometric calibration is needed to produce reflectance map with vicarious calibration. In this study, an optimal image selection method is proposed to improve quality of relative radiometric calibration. The method, relative calibration by the optimal path (RCOP), uses filtered tie points acquired in geometric calibration based on selection optimal image by Dijkstra algorithm. About 100 multispectral images were acquired with a RedEdge-M camera and a fixed-wing UAV. The reflectance map was produced using RCOP and vicarious calibration using ground reference panels. A validation data was processed using irradiance for precise relative radiometric calibration. As a result, the RCOP method showed root mean square error (RMSE) of 0.03–0.10 reflectance to validation data. Therefore, the proposed method can be used to produce precise reflectance map by vicarious calibration.

Abstract Absolute paleointensity (API) of the geomagnetic field can be estimated from volcanic rocks by comparing the natural remanent magnetization (NRM) to a laboratory‐induced thermoremanent magnetization (Lab‐TRM). Plots of NRM unblocking versus Lab‐TRM blocking from API experiments often exhibit nonideal curvature, which can result in biased estimates. Previous work showed that curvature can increase with age; however, selection criteria designed to eliminate such behavior yielded accurate estimates for two‐year‐aged specimens (70.3 ± 3.8 μT; N = 96 specimens out of 120 experiments). API can also be estimated in coercivity space. Here, we use the Tsunakawa‐Shaw (TS) method applied to 20 specimens aged in the laboratory field of 70.0 μT for 4 years, after acquisition of zero‐age (fresh) Lab‐TRM in the same field. Selection criteria for the TS experiment also yielded accurate results (68.5 ± 4.5 μT; N = 17 specimens). In thermal API experiments, curvature is related to internal structure with more single domain‐like behavior having the least curvature. Here we show that the fraction of anhysteretic remanent magnetization demagnetized by low‐temperature treatment was larger for samples with larger thermal curvatures suggesting a magnetocrystalline anisotropy source. We also tested experimental remedies that have been proposed to improve the accuracy of paleointensity estimates. In particular, we test the efficacy of the multi‐specimen approach and a strategy pretreating specimens with low field alternating field demagnetization prior to the paleointensity experiment. Neither yielded accurate results.

Recently, the evidences of climate change have been observed in hydrologic data such as rainfall and flow data. The time-dependent characteristics of statistics in hydrologic data are widely defined as nonstationarity. Therefore, various nonstationary GEV and generalized Pareto models have been suggested for frequency analysis of nonstationary annual maximum and POT (peak-over-threshold) data, respectively. However, the alternative models are required for nonstatinoary frequency analysis because of analyzing the complex characteristics of nonstationary data based on climate change. This study proposed the nonstationary generalized logistic model including time-dependent parameters. The parameters of proposed model are estimated using the method of maximum likelihood based on the Newton-Raphson method. In addition, the proposed model is compared by Monte Carlo simulation to investigate the characteristics of models and applicability.

The double-barrier electromagnetic structure is used for examining the spin-dependent resonant tunneling. The application of a proper electric field subject to the given magnetic barriers helps in achieving significant amount of spin polarization with nice resonant structures.

The cannabinoid (CB1) receptor is a member of the rhodopsin-like G protein-coupled receptor superfamily. The human CB1 receptor, which is among the most expressed receptors in the brain, has been implicated in several disease states, including drug addiction, anxiety, depression, obesity, and chronic pain. Different classes of CB1 agonists evoke signaling pathways through the activation of specific subtypes of G proteins. The molecular basis of CB1 receptor coupling to its cognate G protein is unknown. As a first step toward understanding CB1 receptor-mediated G protein signaling, we have constructed a ternary complex structural model of the CB1 receptor and Gi heterotrimer (CB1-Gi), guided by the x-ray structure of β2-adrenergic receptor (β2AR) in complex with Gs (βAR-Gs), through 824-ns duration molecular dynamics simulations in a fully hydrated 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine bilayer environment. We identified a group of residues at the juxtamembrane regions of the intracellular loops 2 and 3 (IC2 and IC3) of the CB1 receptor, including Ile-2183.54, Tyr-224IC2 224IC2, Asp-3386.30, Arg-3406.32, Leu-3416.33, and Thr-3446.36, as potential key contacts with the extreme C-terminal helixα5 of Gαi. Alamutations of these residues at the receptor-Gi interface resulted in little G protein coupling activity, consistent with the present model of the CB1-Gi complex, which suggests tight interactions between CB1 and the extreme C-terminal helixα5 of Gαi. The model also suggests that unique conformational changes in the extreme C-terminal helix α5 of Gα play a crucial role in the receptor-mediated G protein activation. [ABSTRACT FROM AUTHOR]

Two independent cases of oligochaete worms recovered from Korean women's vaginas are reported. Both specimens were non-parasitic cosmopolitan exotics identified as: microdrile tubificid Limnodrilus hoffmeisteri Claparède, 1862 (Tubificidae) and megadrile dichogastrid Dichogaster bolaui (Michaelsen, 1891) (Octochaetidae) - a new record for Korea. The tubificid is a freshwater euryhaline species that may reach high numbers in organically rich water e.g. in a paddy field, whereas the earthworm is commonly intercepted by quarantine in plant or vegetable cargos and also appears in bathtubs when it inhabits drainage systems. Thus, bathing/douching, field working or picnicking without a blanket are suggested as possible modes of ingress. Oligochaetes rarely occur in live human bodies but the few previous historical records are reviewed. [ABSTRACT FROM AUTHOR]

In this work, a new lab-on-a-chip for rapid analysis of low volume blood samples was designed, fabricated and demonstrated for integration of serum separation, hematocrit evaluation, and protein quantitation. Blood separation was achieved using microchannel flow-based separation. A novel method for evaluating hematocrit from microfluidic flow-separated blood samples was developed using gray scale analysis of a point-and-shoot digital photograph of separated blood in a micochannel. Protein quantitation was subsequently performed in a high surface area-to-volume ratio microfluidic chemiluminescent immunoassay using cell depleted serum produced by microfluidic flow-based separation of whole blood samples. All three steps were achieved in a single microchannel with separation of blood samples and hematocrit evaluation in less than 1 min, and protein quantitation in 5 min. [ABSTRACT FROM AUTHOR]

AbstractHeat shock protein 70 (Hsp70) is a chaperone protein that helps protect against cellular stress, a function that may be co-opted to fight human diseases. In particular, the upregulation of Hsp70 can suppress the neurotoxicity of misfolded proteins, suggesting possible therapeutic strategies in neurodegenerative diseases. Alternatively, in cancer cells where high levels of Hsp70 inhibit both intrinsic and extrinsic apoptotic pathways, a reduction in Hsp70 levels may induce apoptosis. To evaluate and identify, in a single assay format, small molecules that induce or inhibit endogenous Hsp70, we have designed and optimized a microtiter assay that relies on whole-cell immunodetection of Hsp70. The assay utilizes a minimal number of neuronal or cancer cells, yet is sufficiently sensitive and reproducible to permit quantitative determinations. We further validated the assay using a panel of Hsp70 modulators. In conclusion, we have developed an assay that is fast, robust, and cost efficient. As such, it can be implemented in most research laboratories. The assay should greatly improve the speed at which novel Hsp70 inducers and inhibitors of expression can be identified and evaluated. [ABSTRACT FROM AUTHOR]

This technical note presents a simple and disposable lab-on-a-tube (LOT) for point-of-care measurements of multiple analytes. LOT is a one-step device that can perform both sample collection and multi-sensing on-site. Sample collection is conducted by taking advantage of its inherent micro/macro channel structure while multi-sensing is conducted by integrated microsensors. This approach ensures reliable transportation of various samples into the testing area by either passive capillary force or active suction force, thus avoiding the need for a pump or injection components as used in lab-on-a-chip systems. The developed LOT (Diameter = 1 mm, Sensing length = 4.5 mm, Required sample volume = 3.5 μl) is capable of simultaneously quantifying the concentrations of glucose, lactate and oxygen in human serum samples. The result suggests the LOT hold great potential for many point-of-care applications. [ABSTRACT FROM AUTHOR]

Abstract  This paper addresses the problem of approximating a surface-to-surface intersection curve. Accurate computation of an intersection curve is not practical due to the degree explosion problem, when function decomposition is used, and fundamentally is not possible because of some computational reasons. Therefore, in practical applications, an approximate intersection curve with a low degree is extensively used. However, the approximation of an intersection curve needs to consider the topological and numerical aspects together to produce the approximate curve to be as close to the exact one as possible, since approximation inevitably involves both numerical and topological errors. In this paper, algorithms to compute an approximate intersection curve, which are topologically consistent and numerically accurate with the exact intersection curve, are presented. A set of sufficient conditions for an approximate curve to be topologically consistent with the exact one are provided, and the use of a validated ordinary differential equation solver is discussed. The approximate curve is then refined to reduce the error against the exact curve through optimization. The proposed method is demonstrated with examples. [ABSTRACT FROM AUTHOR]

In this work, a new method of rapidly fabricating thermopolymer and elastomer microfluidic channels has been developed and characterized for production of microfluidics with fixed aspect ratio and 3D tapered channels. A unique way to attain a desired channel depth by simply altering channel width is demonstrated. This rapid prototyping method is compatible with replication methods such as injection molding, hot embossing and elastomer casting and offers the ability to fabricate multiple channel depths (5 μm – 1 mm) simultaneously in a single lithographic step. This method yields facile fabrication of 3-dimensionally tapered channels and polymer lab chips. [ABSTRACT FROM AUTHOR]