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In this article, we propose a novel urban waterlogging risk evaluation network (WaRENet) to evaluate the risk of waterlogging. The WaRENet distinguishes whether an urban image involves waterlogging by classification module, and estimates the waterlogging risk levels by multi-class reference objects detection module (MCROD). First, in the waterlogging scene classification, ResNet combined with Se-block is used to identify the waterlogging scene, and lightweight gradient-weighted class activation mapping (Grad-CAM) is also integrated to roughly locate overall waterlogging areas with low computational burden. Second, in the MCROD module, we detect reference objects, e.g., cars and persons in waterlogging scenes. The positional relationship between water depths and reference objects serves as risk indicators for accurately evaluating waterlogging risk. Specifically, we incorporate switchable atrous convolution (SAC) into YOLOv5 to solve occlusions and varying scales problems in complex waterlogging scenes. Moreover, we construct a large-scale urban waterlogging dataset called UrbanWaterloggingRiskDataset (UWRDataset) with 6,351 images for waterlogging scene classification and 3,217 images for reference objects detection. Experimental results on the dataset show that our WaRENet outperforms all comparison methods. The waterlogging scene classification module achieves accuracy of 95.99%. The MCROD module obtains mAP of 54.9%, while maintaining a high processing speed of 70.04 fps. [ABSTRACT FROM AUTHOR]

BackgroundRecurrent hypoglycemia (RH) is well known to impair awareness of hypoglycemia and increase the risk of severe hypoglycemia; the underlying mechanism requires further understanding. We aimed to investigate the metabolic characteristic profile for RH in type 2 diabetes mellitus (T2DM) patients and explore the potential metabolic mechanism and prevention strategies.MethodsWe screened 553 community-based T2DM patients. T2DM with RH (DH group, n=40) and T2DM without hypoglycemia (DC group, n=40) were assigned in the case-control study, matched by propensity score matching. Non-targeted, global metabolite profiling was conducted using ultra-high performance liquid chromatography-mass spectrometry. Principal component analysis and supervised projections to latent structures-discriminant analysis were constructed to evaluate the potential biomarkers. Metabolites with a fold change of >2.0 or 1 were identified as significantly differential metabolites. MetaboAnalyst was performed to analyze the related metabolic pathways.ResultsWe identified 12 significantly distinct metabolites as potential biomarkers of RH, which were enriched in five pathways; the caffeine metabolic pathway was the most dominant related one. Caffeine and its main downstream metabolites (theophylline and paraxanthine, all q

Palladium nanoparticles stabilised by aniline modified polymer immobilised ionic liquid is a remarkably active catalyst for the hydrogenation of CO2 to formate; the initial TOF of 500 h−1 is markedly higher than either unmodified catalyst or its benzylamine and N,N-dimethylaniline modified counterparts and is among the highest to be reported for a PdNP-based catalyst. [ABSTRACT FROM AUTHOR]

RuNPs stabilised by amino‐decorated imidazolium‐based polymer immobilized ionic liquids catalyse the dimethylamine borane mediated reduction of quinolines to 1,2‐dihydroquinoline (DHQ) and 1,2,3,4‐tetrahydroquinoline (THQ). Partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinoline was achieved with 100 % selectivity in toluene under mild conditions. This is the first report of the selective partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinolines with a heterogeneous nanoparticle‐based catalyst. A wide range of substituted quinolines have also been reduced to the corresponding 1,2,3,4‐tetrahydroquinoline with high selectivity and good yields by adjusting the reaction time. The 1,2‐dihydroquinolines readily release dihydrogen in toluene at 60 °C in the absence of catalyst with no evidence for disproportionation and as such are potential organo‐hydride reagents. The initial TOF of 610 mol quinoline converted mol Ru−1 h−1 for the reduction of quinoline is among the highest to be reported for a metal nanoparticle‐based catalyst and the conversion of 96 % obtained after 4 h at 65 °C is significantly higher than its platinum nanoparticle counterpart PtNP@NH2‐PEGPIILS as well as 5 wt/% Ru/C, which only reached 9 % and 11 % conversion, respectively, at the same time. Hot filtration experiments showed that the active species was heterogeneous. [ABSTRACT FROM AUTHOR]

This paper demonstrates a polycrystalline silicon avalanche mode light-emitting device. The unique N+PN+PN+ cascade structure is designed to enhance light intensity via carrier injection engineering, in which the minority carriers are injected from the forward-biased junction to the light emission junction. Visible light can be observed at the reverse-biased PN junctions when the device operating voltage exceeds 20 V. In particular, the phonon-assisted indirect interband recombination of carriers with excess energy may be the main mechanism of photon emission. A specific junction model is proposed to explain that the light intensity peaks are generated primarily via carrier injection. Comparing the spectral measurements of a single polysilicon N+P junction device and the proposed cascade device shows that the strategy of improving the luminous intensity via carrier injection engineering is feasible and effective. [ABSTRACT FROM AUTHOR]

It is highly desired to synchronously impart wearable, fast-healing, and self-adhesive properties in the biocompatible photoactive hydrogel sensor response to strain and temperature for different practical applications. In this work, we designed a multifunctional polyvinyl alcohol (PVA) hydrogel with poly(dopamine)-modified carbon nanotubes (PVA/d-CNTs), which possesses a high self-healing efficiency of 83.08% within 5 s and strong adhesion to different substrates. Furthermore, the PVA/d-CNT sensor realizes full-range monitoring of human motion, with a broad strain range of up to ∼300%, and exhibits an impressive thermal response in human body temperature measurement for health information collection. In addition, the PVA/d-CNT hydrogel with controllable temperature property quickly heats up to ∼85 °C in 50 s under near-infrared laser irradiation, indicating a potential application in photothermal therapy. Finally, a wireless monitoring system for human motion detection and an alarm circuit for high-temperature warning were implemented in the PVA/d-CNT hydrogel sensor, demonstrating a promising potential application in multifunctional electronic skins, artificial intelligence, and intelligent robots. [ABSTRACT FROM AUTHOR]

This is an observational, retrospective, single-center study aimed to determine whether the free triiodothyronine (FT3) to free thyroxine (FT4) ratio was related to acute myocardial infarction (AMI) prognosis in individuals with type 2 diabetes mellitus (T2DM). A total of 294 euthyroid T2DM patients with new-onset AMI were enrolled. FT3/FT4 ratio tertiles were used to categorize patients into Group 1 (FT3/FT4 ≥ 4.3), Group 2 (3.5 ≤ FT3/FT4 < 4.3), and Group 3 (FT3/FT4 < 3.5). Major adverse cardiac events (MACE), including nonfatal myocardial infarction, target vessel revascularization (TVR), and cardiac mortality, served as the primary endpoint. Group 3 demonstrated a considerably higher incidence of MACE than the other two groups over the average follow-up duration of 21 ± 6.5 months (all p < 0.001). Multivariable Cox regression analysis showed that a low FT3/FT4 ratio was an independent risk factor for MACE after AMI (Group 1 as a reference; Group 2: hazard ratio [HR] 1.275, 95% confidence interval [CI]: 0.563–2.889, p = 0.561; Group 3: HR 2.456, 95% CI: 1.105–5.459, p = 0.027). Moreover, the area under the receiver-operating characteristic curve (AUC) indicates a good predictive value of FT3/FT4 ratio for MACE (AUC = 0.70). Therefore, in T2DM patients with AMI, a low FT3/FT4 ratio was strongly linked to poor prognosis. [ABSTRACT FROM AUTHOR]

This article presents a third-order noise-shaping (NS) successive approximation register (SAR) analog-to-digital converter (ADC), which exploits a hybrid error control topology to increase the order of the noise-transfer function (NTF). This scheme is a hybrid of two NS stages, namely, a cascaded integrator feed-forward (CIFF) and an error feedback (EF). This EF-CIFF structure contributes a more effective NS capability and enhances the robustness of the high-order NTF. An improved dither-based digital calibration is developed to mitigate the harmonic distortion caused by the capacitor mismatch. Due to the usage of an averaging filter, this calibration greatly reduces the interference of quantization noise on mismatch extraction while only needing a minimum modification in a standard SAR Topology. Hence, our scheme is simple and inherently robust to the process, voltage, and temperature variation. Based on an 8-bit SAR, our prototype is fabricated in a 130-nm CMOS process. It consumes a 96- $\mu \text{W}$ power when operating at a 2-MS/s sampling frequency with a 1.2-V supply. The proposed NS-SAR yields a peak Schreier figure of merit of 170.7 dB with a signal-to-noise-and-distortion ratio (SNDR) of 79.57 dB at an oversampling ratio of 8. [ABSTRACT FROM AUTHOR]

In this study, transition metal dichalcogenide (TMD) material WS2 and Au nanoparticles were combined with TiO2 to enhance the photocatalytic performance under visible light. The WS2 nanosheets were synthesized from bulk WS2 via ultrasonic process, and the Au nanoparticles were prepared through the reduction reaction from HAuCl4. The composite photocatalysts of WS2/TiO2/Au, TiO2/Au, and WS2/TiO2 were synthesized by a one-step hydrothermal process. The light absorption property of the composites was determined by ultraviolet-visible (UV-vis) photospectroscopy. Surface analysis of WS2 nanosheet, TiO2 nanoparticles, and Au nanoparticles was performed by scanning electron microscopy (SEM). The chemical structure of composites and thickness of WS2 nanosheets were analyzed by Raman spectra. The photocatalytic activity was measured by methylene blue degradation reaction under visible light. These results revealed the photocatalytic behavior of WS2/TiO2/Au, TiO2/Au, and WS2/TiO2 composites, as well as WS2 nanosheets. The WS2/TiO2/Au composite showed improved photocatalytic behavior among all samples. It is believed that the WS2 nanosheet and Au nanoparticle extend the light absorption range from UV region to the visible region, as well as the WS2/TiO2/Au composite reduces the recombination of electrons. This study shows that the enhanced photocatalytic behavior of WS2/TiO2/Au composite can be used as photocatalytic applications in the future. [ABSTRACT FROM AUTHOR]

This article presents a 12-bit column-parallel two-step single-slope analog-to-digital converter (SS ADC). With the merging of analog memory capacitor and input sampling capacitor, the proposed two-step SS ADC realizes simultaneously residue storage and zero-cross detection. The fixed decision point guarantees a static comparator offset. A constant input common-mode level resistor ramp generator, which exploits a current-mode R-2R digital-to-analog converter (DAC) and a variable feedback R-string DAC, is developed to enhance ADC linearity limited by finite common-mode rejection ratio (CMRR) of the operational amplifier. Using a bottom-up foreground self-calibration, harmonic distortion caused by both parasitic capacitor and resistor mismatch is mitigated. This prototype is fabricated using a 130-nm CMOS process. The proposed two-step SS ADC consumes 62- $\mu \text{W}$ power when operating at a 100-KS/s sampling frequency and yields a peak spurious-free dynamic range (SFDR) of 76.47 dB with a signal-to-noise-and-distortion ratio (SNDR) of 60.78 dB. The measured differential nonlinearity (DNL) and the integral nonlinearity (INL) are 0.83/−1 and 4.78/−3.31 LSB, respectively. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles stabilized by imidazolium‐based phosphine‐decorated Polymer Immobilized Ionic Liquids (PPh2‐PIIL) catalyze the hydrolytic evolution of hydrogen from sodium borohydride with remarkable efficiency, under mild conditions. The composition of the polymer influences efficiency with the catalyst based on a polyethylene glycol modified imidazolium monomer (PtNP@PPh2‐PEGPIILS) more active than its N‐alkylated counterpart (PtNP@PPh2‐N‐decylPIILS). The maximum initial TOF of 169 moleH2.molcat−1.min−1 obtained at 30 °C with a catalyst loading of 0.08 mol% is among the highest to be reported for the aqueous phase hydrolysis of sodium borohydride catalyzed by a PtNP‐based system. Kinetic studies revealed that the apparent activation energy (Ea) of 23.9 kJ mol−1 for the hydrolysis of NaBH4 catalyzed by PtNP@PPh2‐PEGPIILS is significantly lower than that of 35.6 kJ mol−1 for PtNP@PPh2‐N‐decylPIILS. Primary kinetic isotope effects kH/kD of 1.8 and 2.1 obtained with PtNP@PPh2‐PEGPIILS and PtNP@PPh2‐N‐decylPIILS, respectively, for the hydrolysis with D2O support a mechanism involving rate determining oxidative addition or σ‐bond metathesis of the O−H bond. Catalyst stability and reuse studies showed that PtNP@PPh2‐PEGPIILS retained 70 % of its activity across five runs; the gradual drop in conversion appears to be due to poisoning of the catalyst by the accumulated metaborate product as well as the increased viscosity of the reaction mixture. [ABSTRACT FROM AUTHOR]

Focal stack images (FoSIs) are a set of 2D images that captured one scene with serial focal depths. The redundancies of FoSIs mainly come from gradual focused depths changes rather than motion of objects. Conventional coding schemes cannot fully exploit such redundancies, leading to coding inefficiency. In this paper, we propose a new Gaussian-Wiener representation to model the gradual focused depths changes among FoSIs. In the representation, image degradation-restoration relations are utilized to describe the focus-defocus changing characteristics of FoSIs. Based on this representation, we propose a new hierarchical coding scheme for fully exploiting the inter-frame redundancies of FoSIs. In the scheme, a Gaussian-Wiener representation based inter prediction (GWR-IP) is presented by embedding Gaussian convolution and Wiener deconvolution into normal video encoder. Block-wise focus-defocus changing of FoSIs can be predicted in bi-directional manner by solving optimization problem. For higher coding efficiency, a Gaussian-Wiener representation based hierarchical prediction structure (GWR-HPS) is also designed and applied in the coding scheme. The proposed coding scheme is performed on 10 test sequences, including 5 synthetic scenes and 5 realistic scenes. Experimental results show that proposed coding scheme can obtain 2.640 dB PSNR gains and 51.830% bitrate savings on average of all test sequences in Low Delay P configuration, 2.123 dB PSNR gains and 43.975% bitrate savings in Low Delay B configuration, and 1.044 dB PSNR gains and 26.078% bitrate savings in Random Access configuration. Particularly, it achieves up to 65.544% bit rate savings and 3.901 dB PSNR increments for test sequence I09 in Low Delay P configuration. Furthermore, ablation test demonstrates that Gaussian representation contributes more on coding performance than Wiener representation and GWR-HPS. [ABSTRACT FROM AUTHOR]

This article presents a low-power code-recombination (CR) analog-to-digital converter (ADC) with generic feature extraction for wearable electrocardiogram (ECG) sensors in wireless body sensor network (WBSN) applications. The CR ADC features a search forward procedure (SFP) and a search backward procedure (SBP) to hunt for part of the quantization steps cutting down bitcycle and power consumption. Also, CR ADC outputs a digital stream named $K$ data served as a compressed feature. A prototyped chip including a proposed ADC is fabricated in a 0.13- $\mu \text{m}$ CMOS process. With a 0.6-V supply voltage and a 10-kS/s sampling rate, the measured signal-to-noise-distortion range (SNDR) and spurious-free dynamic range (SFDR) are 58.34 and 70.2 dB, respectively. The ADC consumes only 40-nW power when input residue is within the prediction range defined by ADC’s resolution and the reference voltage, achieving a figure-of-merit (FoM) of 6.2 fJ/conversion-step. The data $K$ occupy 2/5 of the raw data and are conducted to categorize cardiovascular diseases illustrating at least 96% accuracy. [ABSTRACT FROM AUTHOR]

In this study, the preparation of ternary photocatalyst using a simple hydrothermal method is shown with high performance. A ternary composite consisting of tungsten sulfide (WS 2) nanosheets, titanium oxide (TiO 2) and gold (Au) nanoparticles is used to the extend the visible-light absorption region of TiO2. The morphological and spectroscopic natures of the prepared sample were analyzed using scanning electron microscopy (SEM), Raman spectroscopy and ultraviolet–visible (UV–vis) photospectroscopy. The photocatalysis measurement for photodegradation of methylene blue dye was performed under the visible light. The photocatalytic studies suggest that in the ternary composite, consisting of three materials with different energy levels, the electrons excited form a cycle to lower the probability for the recombination of electron–hole pairs enhancing the property of photocatalytic activity of TiO2. [ABSTRACT FROM AUTHOR]