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This research investigates the differences in AERMOD-predicted pollutant concentrations across input source types (AREAPOLY, VOLUME, LINE, RLINE, and RLINEXT without barriers). AERMOD (version 19191) microscale dispersion modeling is performed for the Atlanta I-75/I-575 Northwest Corridor (NWC) subarea in the U.S., including freeway corridors, managed lanes, connecting arterials, and intersections serving the NWC system. Modeling is performed for all link-receptor pairs, for each hour of the year, using the approved AERMET meteorological files (24 h × 365 days in 2019) from Georgia Environmental Protection Division (GA EPD), and emissions rates are estimated using MOVES-Matrix, based on predicted speed and volume by hour (output from ARC’s ABM2020 travel demand model). The AERMOD comparative analyses are performed for the same receptor sets, link-level volumes and speeds, and fleet compositions, across the five source types to generate comparative model results by input source type for the subarea. Results indicate concentrations from RLINEXT and RLINE were similar, with differences smaller than 0.05%, and their results were significantly higher than other source types. The results from AREAPOLY were similar to those from LINE (both smaller than RLINE and RLINEXT results). It is indicated that the results from VOLUME are systematically different from AREAPOLY and LINE for both downwind (much lower than AREAPOLY and LINE) and upwind (much higher than AREAPOLY and LINE) of the sources, and the sensitivity analysis indicates these predictions occur when wind speeds are low (less than approximately 2.5 m/s), which is because the enhanced wind meander approach employed with VOLUME is different from other source types.

Many transit providers changed their schedules and route configurations during the COVID-19 pandemic, providing more frequent bus service on major routes and curtailing other routes, to reduce the risk of COVID-19 exposure. This research first assessed the changes in Metropolitan Atlanta Rapid Transit Authority (MARTA) service configurations by reviewing the pre-pandemic versus during-pandemic General Transit Feed Specification (GTFS) files. Energy use per route for a typical week was calculated for pre-pandemic, during-closure, and post-closure periods by integrating GTFS data with MOVES-Matrix transit energy and emission rates (MOVES signifying MOtor Vehicle Emission Simulator). MARTA automated passenger counter data were appended to the routes, and energy use per passenger-mile was compared across routes for the three periods. The results showed that the coupled effect of transit frequency shift and ridership decrease from 2019 to 2020 increased route-level energy use for over 87% of the routes and per-passenger-mile energy use for over 98% of the routes. In 2021, although MARTA service had largely returned to pre-pandemic conditions, ridership remained in an early stage of recovery. Total energy use decreased to about pre-pandemic levels, but per-passenger energy use remained higher for more than 91% of routes. The results confirm that while total energy use is more closely associated with trip schedules and routes, per-passenger energy use depends on both trip service and ridership. The results also indicate a need for data-based transit planning, to help avoid inefficiency associated with over-provision of service or inadequate social distancing protection caused by under-provision of service.

Wearable sensors have recently attracted extensive interest not only in the field of healthcare monitoring but also for convenient and intelligent human-machine interactions. However, challenges such as wearable comfort, multiple applicable conditions, and differentiation of mechanical stimuli are yet to be fully addressed. Herein, we developed a breathable and waterproof electronic skin (E-skin) that can perceive pressure/strain with nonoverlapping signals. The synergistic effect from magnetic attraction and nanoscaled aggregation renders the E-skin with microscaled pores for breathability and three-dimensional microcilia for superhydrophobicity. Upon applied pressure, the bending of conductive microcilia enables sufficient contacts for resistance decrease, while the stretching causes increased resistance due to the separation of conductive materials. The optimized E-skin exhibits a high gauge factor of 7.747 for small strain (0-80%) and a detection limit down to 0.04%. The three-dimensional microcilia also exhibit a sensitivity of -0.0198 kPa

Surface enhanced Raman scattering (SERS) is a rapid and nondestructive technique that is capable of detecting and identifying chemical or biological compounds. Sensitive SERS quantification is vital for practical applications, particularly for portable detection of biomolecules such as amino acids and nucleotides. However, few approaches can achieve sensitive and quantitative Raman detection of these most fundamental components in biology. Herein, a noble-metal-free single-atom site on a chip strategy was applied to modify single tungsten atom oxide on a lead halide perovskite, which provides sensitive SERS quantification for various analytes, including rhodamine, tyrosine and cytosine. The single-atom site on a chip can enable quantitative linear SERS responses of rhodamine (10Supplementary material is available for this article at 10.1007/s40843-022-1968-5 and is accessible for authorized users.表面增强拉曼散射(SERS)是一种快速且无损的化学和生物分子检测技术. 高灵敏且定量化的SERS检测技术对其在实际中的应用至关重要, 尤其是对生物分子如氨基酸和碱基的便携化检测. 但是鲜有技术手段能够实现对这些最基本的生物分子进行高灵敏且定量化的拉曼检测. 我们提出了一种无需贵金属的单原子位点修饰芯片策略, 用钨单原子氧化物修饰铅卤钙钛矿芯片, 实现了多种检测物的高灵敏定量化识别, 包括罗丹明、 酪氨酸和胞嘧啶. 芯片上单原子位点技术能够实现对罗丹明、 酪氨酸和胞嘧啶的线性检测, 相应的定量化区间分别为: 10

Many patients after sphincter-preserving surgery experienced anorectal functional disturbances which were known as low anterior resection syndrome (LARS). Although many studies investigated LARS, there was inconsistency of their assessment tools and results. The aim of this systematic review was to elucidate the incidence and risk factors of LARS by a validated tool—LARS score. A systematic literature search in Pubmed, Embase, and Cochrane Library was conducted in April 2020. Studies investigating patients who were evaluated by LARS score 1 year after their sphincter-preserving surgery due to rectal cancer were included. Meta-analysis of incidence was conducted using the double arcsine method. Meta-analysis of each risk factor was conducted using a random effects model. A total of 50 studies were included. The pooled incidence of major LARS was 44% (95% CI 40–48%; I2 = 88%; 36 studies). Long course neoadjuvant radiotherapy (OR 2.89, 95% CI 2.06–4.05; I2 = 47%; P

Exploration of wearable strain sensors in diverse application scenarios is one global requirement for shaping the future of our intelligent community. However, state-of-the-art wearable devices still face challenges such as interference under humid conditions and chemical/mechanical fragility. Here, a facile and fluorine-free approach is introduced to realize a sensitive, robust and superhydrophobic strain sensor via the in situ formation of microcilia on the PDMS surface, followed by a two-step swelling process. The swelling process facilitates the penetration of carbon black nanoparticles into the PDMS matrix to render the conductive network suitable for strain sensing, while the decoration of silica nanoparticles along with the microcilia forms a hierarchical architecture for water repellency. The sensing performance was optimized, including the sensitivity (gauge factor of 354), working range (up to 250%), and long-term stability (>10 000 cycles). The superhydrophobic surface exhibits excellent resistance to mechanical abrasion, chemical corrosion, and high-speed water impact, etc. Demonstrations, such as body motion perception, wireless and underwater communications, Morse code generation, underwater jet impact, reveal the potential of the sensor as a robust platform for broad applications not only in air but also for underwater or under harsh condition uses.

Rapid droplet detachment from the surface in a "pancake rebound" has recently attracted abundant interest owing to the contact time control for applications in anti-icing and self-cleaning. Even though the pancake rebound on rigid substrates has been realized, the establishment of artificial structures on a flexible counterpart with droplet impact behavior studies has rarely been reported. Here, we introduced a facile approach to fabricating a flexible superhydrophobic film decorated with tunable hierarchical micro/nanostructures for water repellency. With the appropriately optimized architecture, the pancake rebound with reduced contact time can be realized when reaching a specific Weber number on the microcones. We also observed that the pancake rebound on microcilia could be realized by regulating the energy-transfer process on the flexible film during the droplet impact. A tightly stretched and suspended film can serve as the "spring" to store the elastic energy transferred from the kinetic energy of the penetrated droplet while converting back to kinetic energy during the emptying process with a reduced contact time of 5.2 ms. With the preserved water repellency on diverse curvatures, the study raises a new avenue to realize superhydrophobic surfaces and rapid droplet detachment with the potential for a broader spectrum toward practical scenarios in our daily life.

Objectives. There have been no fully validated tools for the rapid identification of surgical patients at risk of intraoperative hypothermia. The objective of this study was to validate the performance of a previously established prediction model in estimating the risk of intraoperative hypothermia in a prospective cohort. Methods. In this observational study, consecutive adults scheduled for elective surgery under general anesthesia were enrolled prospectively at a tertiary hospital between September 4, 2020, and December 28, 2020. An intraoperative hypothermia risk score was calculated by a mobile application of the prediction model. A wireless axillary thermometer was used to continuously measure perioperative core temperature as the reference standard. The discrimination and calibration of the model were assessed, using the area under the receiver operating characteristic curve (AUC), Hosmer–Lemeshow goodness-of-fit test, and Brier score. Results. Among 227 participants, 99 (43.6%) developed intraoperative hypothermia, and 10 (4.6%) received intraoperative active warming with forced-air warming. The model had an AUC of 0.700 (95% confidence interval [CI], 0.632–0.768) in the overall cohort with adequate calibration (Hosmer–Lemeshow χ2 = 13.8, P = 0.087 ; Brier score = 0.33 [95% CI, 0.29–0.37]). We categorized the risk scores into low-risk, moderate-risk, and high-risk groups, in which the incidence of intraoperative hypothermia was 23.0% (95% CI, 12.4–33.5), 43.4% (95% CI, 33.7–53.2), and 62.7% (95% CI, 51.5–74.3), respectively ( P for trend

Recently, flexible devices that can implement both pressure and shear force monitoring have attracted abundant interest. Even though flexible sensors with optimized pressure monitoring have been widely explored, the shear branch is yet to be fully addressed as it is restricted by the device assembly and structural features. Herein, we present the magnetic field-assisted in situ formation of spine arrays as the dielectric layer for a capacitive sensor that can respond to both normal pressure and shear force. The template-free and facile approach can not only induce a spine-shaped dielectric as a highly compressible medium for pressure sensing but can also simultaneously realize the device assembly for sustainable shear force monitoring. The capacitive sensor exhibits sensitive pressure monitoring with a detection limit of 2 Pa and possesses reliable and recoverable shear perception with a sensitivity of 0.0752 N−1 (0.015–0.50 N) and 0.0177 N−1 (0.50–1.30 N). As a proof of concept, the device was applied as a wearable motion indicator, artificial intelligence, and body force sensor in terms of pressure and shear force recognition. We believe that the demonstrated methodology can be promising for future wearable electronics thanks to the advantages such as facile production, competitive detection performance, and capability of pressure-shear monitoring.

The control of underwater bubble behavior on a solid surface has great research significance. However, the control of the spontaneous directional transport and collection of numerous underwater bubbles remains a challenge. A new technique of a metal mesh with superhydrophobic/hydrophobic properties is demonstrated here, which creates a wettability gradient coupled with a microporous array by means of pulsed fiber laser ablation and chemical modification of the aluminum sheet. The resultant wettability surface effectively achieved the spontaneous movement of bubbles along the directional wettability gradient (superaerophobicity to aerophilicity) and through the metal mesh (aerophilicity to superaerophilicity) in the direction of decreasing free energy. Theoretical analysis accounted first for the spontaneous sliding of bubbles on the wettability gradient surface as a result of the action of an unbalanced surface tension force and second for the spontaneous transition of bubbles from the aerophilic to superaerophilic side as a result of the combined action of Laplace pressure and buoyancy. A device with the capability of directional transportation and collection of underwater bubbles was designed based on the samples with a wettability gradient and a superhydrophobic/hydrophobic microporous array as the core components. The potential application is laser ablation of wettability gradient surfaces and metal mesh with superhydrophobic/hydrophobic properties for directional transportation and collection of underwater bubbles.

Background and aim Malignant mesothelioma (MM), being a rare and aggressive carcinoma, can barely be cured. Incidence of this cancer will keep climbing up in the next few decades since its major carcinogen, asbestos, is still in use in many countries. Unfortunately, prognosis of MM is unsatisfactory principally due to poor early diagnosis as a result of its long latency period and ambiguous symptoms. Lipids are known to contribute to cellular structure, signaling, and energy storage, and are widely reported to be related with tumorigenesis. Therefore, we aim to discover novel lipid biomarkers by plasma-based lipidomics that may improve MM diagnosis. Methods Plasma samples from 25 MM patients and 32 healthy controls (HCs) were collected and analysed using a high-throughput liquid chromatography-mass spectrometry (LC-MS). Univariate and multivariate analyses were subsequently performed to visualize the separation trend between two groups and to screen for differential feature ions. Ions were annotated using LipidSearch 4.2 and their enriched pathways were detected on LIPEA. Receiver operating curves (ROC) were used for analysing each annotated lipid’s diagnostic value. Survival analyses were performed to investigate each lipid’s prognostic value. Results In supervised partial least squares discriminant analysis (PLS-DA), clear separation between MM and HC groups was observed. A total of 34 differential lipids were annotated, among which 5 upregulated and 29 downregulated. Levels of plasma triacylglycerols (TGs) were higher in smoking versus non-smoking patients, and lower in female versus male patients. The top six lipids possessing highest diagnostic value included two phosphatidylethanolamines (PEs), two phosphatidylcholines (PCs) and two ceramides. Moreover, elevated circulating TG levels were associated with poorer survival, whereas increased monohexosylceramide (Hex1Cer) might be beneficial. Conclusions Our study revealed differentially expressed lipid patterns in MM and HC. PC, PE, and ceramides showed outstanding diagnostic performance, while TG and Hex1Cer exhibited significant prognostic values. Nevertheless, more studies should verify these trends as well as further investigating underlying mechanisms.

COVID-19 is an acute respiratory disease caused by SARS-CoV-2, which has high transmissibility. People infected with SARS-CoV-2 can develop symptoms including cough, fever, pneumonia and other complications, which in severe cases could lead to death. In addition, a proportion of people infected with SARS-CoV-2 may be asymptomatic. At present, the primary diagnostic method for COVID-19 is reverse transcription-polymerase chain reaction (RT-PCR), which tests patient samples including nasopharyngeal swabs, sputum and other lower respiratory tract secretions. Other detection methods, e.g., isothermal nucleic acid amplification, CRISPR, immunochromatography, enzyme-linked immunosorbent assay (ELISA) and electrochemical sensors are also in use. As the current testing methods are mostly performed at central hospitals and third-party testing centres, the testing systems used mostly employ large, high-throughput, automated equipment. Given the current situation of the epidemic, point-of-care testing (POCT) is advantageous in terms of its ease of use, greater approachability on the user's end, more timely detection, and comparable accuracy and sensitivity, which could reduce the testing load on central hospitals. POCT is thus conducive to daily epidemic control and achieving early detection and treatment. This paper summarises the latest research advances in POCT-based SARS-CoV-2 detection methods, compares three categories of commercially available products, i.e., nucleic acid tests, immunoassays and novel sensors, and proposes the expectations for the development of POCT-based SARS-CoV-2 detection including greater accessibility, higher sensitivity and lower costs.

Droplet manipulations are critical for applications ranging from biochemical analysis, medical diagnosis to environmental controls. Even though magnetic actuation has exhibited great potential, the capability of high-speed, precise manipulation, and mixing improvement covering a broad droplet volume has not yet been realized. Herein, we demonstrated that the magnetic actuation could be conveniently achieved via decorating the magnetically responsive film with microcilia. Under magnetic field, the film can quickly response with localized deformation, along with the microcilia to realize the surface superhydrophobicity for droplet manipulation with velocity up to ∼173 mm/s covering a broad volume of 2-100 μL. The robust system further allows us to realize rapid and complete droplet mixing within ∼1.6 s. In addition, the microcilia decorated surface can preserve the robust superhydrophobicity after various stability tests, for example, normal pressing, chemical corrosion, and mechanical abrasion, exhibiting the possibility toward the long-term and real applications. With the multifunctional demonstrations such as obvious mixing improvement, parallel manipulation, and serial dilution, we believe that the methodology can open up a magnetic field-based avenue for future applications in digital microfluidics, and biochemical assays, etc.

Rational design of highly efficient electrocatalysts for sustainable energy conversion is critical but also challenging. Both the composition and surface property of catalyst are pivotal for the advanced water electrolysis. Herein, the Ru/Co(OH)2 nanosheet array with tunable compactness on carbon cloth is designed via a facile two-step process. Especially, the as-synthesized Ru/Co(OH)2 nanosheet array with superhydrophilicity and superaerophobicity surface is conducive to the acceleration of mass transport, which is realized by facilitating the access of electrolyte and alleviating the “bubble shielding effect” for gas bubble diffusion. Consequently, the fabricated nanostructured Ru/Co(OH)2 array based catalyst shows an outstanding HER performance in 1.0 M KOH, which only requires a low overpotential of 35 mV to reach 10 mA cm−2 and demonstrates strong stability at a high current density of 500 mA cm−2 upon long-term duration operation. Additionally, the enhanced Faradic efficiency under high current density is achieved by the optimized nanoarray structure. It is believed the present work could provide a novel perspective for tuning the catalytic activities of nanostructured electrode and beyond.

Two-dimensional (2D) materials have recently attracted abundant interest as cost-effective surface-enhanced Raman scattering (SERS) substrates for precise molecular monitoring. However, the challenge of large-area substrate production with high stability and uniformity still imposes unavoidable barrier of 2D materials for practical applications. In this work, we show that large-scale MS2 (M = Mo, W) vertical nanosheets with mixed 1T/2H phases on metal foils as SERS substrates can be fabricated by a simple and low-cost route. We find that the detection limits of MoS2 and WS2 can be up to 5 × 10–8 M for Rhodamine 6G (R6G), which are much lower than those of most semiconductor SERS substrates. Moreover, the recyclable and scalable substrates provide excellent uniformity and reproducibility on the whole substrates (3 × 4 cm2), and the Raman signals keep unchanged after 30 days. The excellent SERS performance is contributed by the high content of 1T phase and 1T-2H heterostructures that significantly improve the charge transfer process, and rich edges that enable sufficient interaction with the interested molecules. Our findings offer potential candidates for practical applications in the food security field and provide insight to design novel SERS substrates.

Surface-enhanced Raman scattering (SERS) has been considered as one powerful tool for trace detection in various fields from biochemical analysis to environmental monitoring. Even metallic nano-particles based platform has proved to be an efficient way for signal enhancement, the random distribution of plasmonic nano-particles and target analytes normally impose restrictions on the detection limit and signal uniformity. In this work, we propose a facile and effective strategy to realize the dynamic enrichment of analyte molecules and AuNPs within the evaporating micro-droplet for SERS based on the superhydrophobic and magnetically functionalized PDMS membrane. Integrated with the computer-based controller, the membrane decorated with hydrophobic silica nanoparticles enables to maintain the de-pinning status of the micro-droplet by driving the droplet back-and-forth during the evaporation and enrichment process. Through optimizing the parameters of the dynamic enrichment strategy, the diameter of the final deposition pattern of the micro-droplet (containing 10 μL AuNPs and 10 μL R6 Gmolecules) has been concentrated to ∼ 0.4 mm thanks to the continuous de-pinning effect. The Raman signal has been further intensified by ∼3.9 times with optimized uniformity (RSD of ∼8.2 %) compared with the static enrichment mode on superhydrophobic surface. Thanks to the ultra-enrichment capability, the platform can well detect the concentration of R6 G probe molecules down to 10−17 mol/L. We believe that the proposed approach can be promising for exploiting cost-effective and versatile platform in future application such as biological analysis, chemical micro-reactions, and trace molecule detections.

As different faces have different features, the degree of memorability of faces are different, which are named memorability in this paper. We mainly study the relation between the memorability and different features such as the geometrical features of the faces, the location of eyes, the size of mouth and eyes and the Histogram of Oriented Gradient (HOG). We use SVR model to regress the features of face images, and predict the memorability score. Finally, we use the spearman rank correlation coefficient and residual sumof- squares error to analyze the correlation and error of the predicted memorability score with ground truth.

Hyperspectral imaging has recently been introduced into face and palmprint recognition and is now drawing much attention of researchers in this area. Compared to simple 2D imaging technology, hyperspectral image can bring much more information. Due to its ablity to jointly explore the spatial-spectral domain, 3D Gabor wavelets have been successfully applied for hyperspectral palmprint recognition. In this approach, a set of 52 three-dimensional Gabor wavelets with different frequencies and orientations were designed and convolved with the cube to extract discriminative information in the joint spatial-spectral domain. However, there is also much redundancy among the hyperpecstral data, which makes the feature extraction computationally expensive. In this paper, we propose to use AP (affinity propagation) based clustering approach to select representative band images from available large data. As the number of bands has been greatly reduced, the feature extraction process can be efficiently speed up. Experimental results on the publicly available HK-PolyU hyperspectral palmprint database show that the proposed approach not only improves the efficiency, but also reduces the EER of 3D Gabor feature based method from 4% to 3.26%.