A proper understanding of urban functions is fundamental to prevent urban problems and promote better built environments. While previous studies focus mainly on inferring urban function types, there ...are few understandings of how urban functions organize spatially from the perspective of spatial co-occurrence of activities. To address this issue, we propose a new method to mine the co-location patterns (CPs) of urban activities with ‘Point-of-Interest’ (POI) data. We implement a comparative analysis with 25 major cities in China to recognize their commonness/distinctiveness in the spatial organization of urban functions. We identify nearly a thousand unique POI CPs for these cities. By aggregating the resulting CPs, we create the urban function graphs for each city to reflect the inter-connections of different function types. Most cities have relatively high graph densities, suggesting the mixture of urban functions in the space. Despite the relatively similar structures among cities, their manifestations of POI CPs vary greatly from one city to another. The commonly found POI CPs (witnessed in at least 20 cities) only contributes to 6.2% of the total unique POI CPs. The cities of Wuxi, Chengdu, Ningbo, Shenzhen and Chongqing have most distinctive urban functional structures compared to other cities.
•A CPs mining algorithm is applied to investigate urban functions for 25 cities.•6.2% of the POI CPs can be commonly witnessed in >20 cities.•Wuxi, Chengdu, Ningbo, Shenzhen and Chongqing have distinctive urban functional structure.
Aluminum–air (Al–air) battery is one of the most promising candidates for next-generation energy storage systems because of its high capacity and energy density, and abundance. The polyacrylic acid ...(PAA)-based alkaline gel electrolyte is used in all-solid-state Al–air batteries instead of aqueous electrolytes to prevent leakage. The optimal gel electrolyte exhibits an ionic conductivity of 460 mS cm−1, which is close to that of aqueous electrolytes. The Al–air battery peak capacity and energy density considering only Al can reach 1166 mAh g−1-Al and 1230 mWh g−1-Al, respectively, during constant current discharge. The battery prototype also exhibits a high power density of 91.13 mW cm−2. For the battery is a laminated structure, area densities of 29.2 mAh cm−2 and 30.8 mWh cm−2 are presented to appraise the performance of the whole cell. A novel design to inhibit anodic corrosion is proposed by separating the Al anode from the gel electrolyte when not in use, thereby effectively maintaining the available capacity of the battery.
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•PAA-based alkaline gel electrolyte with a high ionic conductivity of 460 mS cm−1.•Peak capacity and energy densities of 1166 mAh g−1-Al and 1230 mWh g−1-Al.•High area densities of 29.2 mAh cm−2 and 30.8 mWh cm−2 of the whole battery.•High power density of 91.13 mW cm−2.•A novel separation design to inhibit anodic corrosion when not in use.
Time-resolved inductively coupled plasma mass spectrometry (ICP-MS) for studying cellular heterogeneity or detecting metals in single cells draws increasing attention in the recent years. Considering ...the full width of a single-cell event is about 0.5–0.9 ms, dependent on the duration of the ion plume generation in typical ICP condition, dwell time shorter than the transient event was suggested for fully profiling it. Herein we investigated the effect of dwell time (0.1–10.0 ms) on the signal profiles of single-cell events, signal-to-background ratio, duty cycle of detection, the limit of detection, and the ability of cell counting by the time-resolved ICP-MS, using yeast (
Saccharomyces cerevisiae
) cells as example. Two calibration equations with respect to the length of dwell time (0.1 ms or 5.0 ms), simply using dissolved metal standard solutions, were constructed and successfully applied to the determination of K, Mg, Zn, Mn, and Cu in single yeast cells. The limit of detection (LOD, fg per cell) obtained at dwell time 0.1 ms was 1.68 (K), 0.29 (Mg), 0.17 (Zn), 0.01 (Mn), and 0.02 (Cu) for single-cell analysis of yeast cells; the LOD (fg per cell) at 5.0 ms was 80.0 (K), 10.3 (Mg), 1.6 (Zn), 0. 14 (Mn), and 0.24 (Cu), respectively. The results showed that a short dwell time leading to high signal-to-background ratio and low LOD was a prerequisite for the quantitative analysis of ultra-trace content of metals in single cells.
The development and optimization of transition metal-based bifunctional electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are critical for high-efficient ...water splitting. Herein, we propose a carbon dots-oriented strategy for fabricating nitrogen-doped carbon dots/fungus-like CoP microsphere composite on Ni foam (CoP-NCDs/NF). Owing to its unique structure and the strong interactions between carbon dots and CoP, the newly developed CoP-NCDs/NF electrode exhibits significantly enhanced HER and OER bifunctional catalytic activities, with overpotentials as low as 103 and 226 mV at a current density of 10 mA cm−2, respectively. Accordingly, the CoP-NCDs/NF displays excellent overall water splitting performance with a low cell voltage of 1.55 V at 10 mA cm−2 and great stability in a two-electrode alkaline electrolyzer. This study provides an alternative pathway on rationally designing and fabricating carbon dots-based materials for high performance water electrolysis and other energy conversion fields.
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•Fungus-like CoP microspheres were synthesized via a CDs-oriented method.•The CoP-NCDs/NF electrode exhibited improved electrocatalytic performance in HER, OER and overall water splitting.•The unique structure and the strong interactions contributed to the excellent electrocatalytic activity.
Studies examining whether diet sugar intake increases the risk of depression have produced inconsistent results. Therefore, we investigated this relationship, using the US' National Health and ...Nutrition Examination Survey (NHANES) database.
This cross-sectional study included 18,439 adults (aged ≥ 20 years) from NHANES (2011-2018). Depressive symptoms were assessed using the nine-item version of the Patient Health Questionnaire (PHQ-9). Covariates, including age, sex, race/ethnicity, poverty-income ratio, education, marital status, hypertension, diabetes mellitus, cardiovascular disease, alcohol intake, smoking status, physical activity, and dietary energy intake, were adjusted in multivariate logistic regression models. Subgroup and threshold saturation effect analyses were performed.
After adjusting for potential confounders, we found that a 100 g/day increase in dietary sugar intake correlated with a 28% higher prevalence of depression (odds ratio = 1.28, 95% confidence interval = 1.17-1.40, P < 0.001).
Dietary sugar intake is positively associated with depression in US adults.
Currently, the deep integration of the Internet of Things (IoT) and edge computing has improved the computing capability of the IoT perception layer. Existing offloading techniques for edge computing ...suffer from the single problem of solidifying offloading policies. Based on this, combined with the characteristics of deep reinforcement learning, this paper investigates a computation offloading optimization scheme for the perception layer. The algorithm can adaptively adjust the computational task offloading policy of IoT terminals according to the network changes in the perception layer. Experiments show that the algorithm effectively improves the operational efficiency of the IoT perceptual layer and reduces the average task delay compared with other offloading algorithms.
By using the cogredience theories of an alternate matrix, a symmetric matrix and a Hermitian-symmetric matrix, we will find a special family of generator matrices for any linear code, and then using ...the special family of generator matrices, we will provide a general method to construct a linear complementary dual (LCD) code (resp. a Hermitian LCD code) from any given linear code. Still using the special family of generator matrices for LCD codes (resp. Hermitian LCD codes), we will present the enumeration of all n,k LCD codes (resp. Hermitian LCD codes).
Promoting the browning of white fat may be a potential means of combating obesity. Therefore, in this study, we investigated the effect of resveratrol (RES) on the body weight and browning of white ...fat in high-fat diet (HFD)-induced obese mice and the potential associated mechanism in vivo. Eight-week-old male mice were randomized to receive different treatments: (1), chow without any additional treatment (chow); (2), chow plus 0.4% resveratrol (chow-RES); (3), HFD without any additional treatment (HFD); and (4), HFD plus 0.4% resveratrol (HFD-RES). After 4 weeks of feeding, additional 8-week-old male recipient mice were randomly allocated to the following 4 treatments: (5), HFD and received feces from chow-fed mice; (6), HFD and received feces from chow-RES-fed mice; (7), HFD and received feces from HFD-fed mice; and (8), HFD and received feces from HFD-RES-fed mice. RES treatment significantly inhibited increases in fat accumulation, promoted the browning of white adipose tissue (WAT) and alleviated gut microbiota dysbiosis in HFD-fed mice. Subsequent analyses showed that the gut microbiota remodeling induced by resveratrol had a positive role in WAT browning, and sirtuin-1 (Sirt1) signaling appears to be a key component of this process. Overall, the results show that RES may serve as a potential intervention to reduce obesity by alleviating dysbiosis of the gut microbiota.
Failure mode and effects analysis (FMEA) was used to analyse all possible failure modes for each product in a system and all possible effects of failure modes on the system, to classify each failure ...mode and to propose solutions and preventative measures. It is undeniable that the traditional FMEA method has been widely criticized for its simple scoring and single algorithm. To improve the usability of FMEA, hesitation fuzzy preference relation sets (HFPRs) based on hesitant fuzzy sets have been introduced into FMEA research because of their good fuzziness and uncertainty properties. Most existing consistency-based algorithms for HFPR processing, however, do not consider the possible coherence deviation of the reluctant fuzzy set itself, which includes multiplicative consistency (MC) theory, which will result in the reduced accuracy of results from such algorithms, in addition to not supporting group decision-making well in heterogeneous environments. At the same time, when building a group consensus, constantly adjusting HFPRs through group decision feedback can easily lead to conservative or radical scoring by experts. Therefore, an excellent hybrid FMEA assessment method is studied in this paper. In this approach, an extended multiplicative consistency equation is constructed by extending the applicability of MC in the treatment of HFPR, and on this basis, a mathematical model with the ability to deal with sets of heterogeneous fuzzy preference relations (H-HFPRs) is constructed. Lastly, based on the predictability principle of the occurrence level (O), a scoring correction algorithm is constructed based on group consensus theory to reduce the conservative or aggressive bias of the expert group in the results. The new method was used in the risk assessment of Chengbei oilfield subsea pipeline engineering, and the results are compared to several existing methods in order to verify the effectiveness of the proposed method.
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