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The increasing frequency of urban flood disasters presents a significant obstacle to urban sustainability. Urban flood management aims to reduce the flood occurrences, currently addressed through urban drainage systems. Previous studies have demonstrated future precipitation extremes will pose larger pressure on urban drainage network, but when and where the pressure will reach a dangerous level have never been assessed in any city of China. This study establishes the initial framework for identifying critical decades and hot spots of urban drainage pressure changes due to future climate change, through a case study conducted in southern China (Haining city). Urban drainage pressure was assessed by a combination of the urban drainage model known as the Storm Water Management Model (SWMM) and pipe statistics. Using climate projections from the latest phase of Coupled Model Intercomparison Project (CMIP6) under four typical SSP-RCP (shared socioeconomic pathway-representative concentration pathway) scenarios, we project the changes in urban drainage pressure by 21st century, and identify the key decades and high risk areas with the occurrence of dangerous pressure levels. The results indicate an overall upward trend in urban drainage pressure for Haining city, with over 97% of the flooding nodes projected to firstly reach the dangerous level by the 2030 s. Comparisons of the patterns under different SSP-RCP scenarios, suggest that a higher forcing pathway would expedite the deterioration of urban drainage pressure, particularly in urban areas with lower DEM and high building intensity. This has broad implications for better informing disaster management and policy-making in similar cities, especially those with inadequate drainage capacities.

Tetrabromobisphenol A (TBBPA), Tetrachlorobisphenol A (TCBPA), Tetrabromobisphenol S (TBBPS) and their derivatives as the most widely used halogenated flame retardants (HFR), had been employed in the manufacturing industry to raise fire safety. HFRs have been shown to be developmentally toxic to animals and also affect plant growth. However, little was known about the molecular mechanism responded by when plants were treated with these compounds. In this study, when Arabidopsis was exposed to four HFRs (TBBPA, TCBPA, TBBPS-MDHP, TBBPS), the stress of these compounds had different inhibitory effects on seed germination and plant growth. Transcriptome and metabolome analysis showed that all four HFRs could influence the expression of transmembrane transporters to affect ion transport, Phenylpropanoid biosynthesis, Plant-pathogen interaction, MAPK signalling pathway and other pathways. In addition, the effects of different kinds of HFR on plants also have variant characteristics. It is very fascinating that Arabidopsis shows the response of biotic stress after exposure to these kinds of compounds, including the immune mechanism. Overall, the findings of the mechanism recovered by methods of transcriptome and metabolome analysis supplied a vital insight into the molecular perspective for Arabidopsis response to HFRs stress.

In the present study, the response of North Pacific storm tracks to spatial multiscale (large-scale and mesoscale) sea surface temperature anomalies (SSTAs) in stable state of Kuroshio Extension (KE-related SSTAs) system are investigated. The results show that storm tracks are significantly strengthened with local enhanced rainfall in the central North Pacific and near the west coast of the North American continent in response to KE-related large-scale SSTAs, while they shift to the north and are significantly strengthened in the central-eastern North Pacific and Gulf of Alaska with remote impact on precipitation along west coast of North America continent in response to KE-related mesoscale SSTAs. The anomalous storm tracks influenced by KE-related SSTAs at different spatial scales are closely related to the locations of low-level baroclinicity. The response of horizontal advection of temperature to different scales of KE-related SSTAs in the lower atmosphere plays an important role in resulting baroclinicity anomalies.

Based on the observational hourly precipitation data and the ERA5 reanalysis datasets, the short-term forecasts of the warm-sector heavy rainfall with warm-type shear line (WRWS) events over the coastal areas of the Yangtze–Huaihe River (YHR) are investigated in the regional business model Precision Weather Analysis and Forecasting System (PWAFS). Evaluations and diagnoses are carried out via objective estimations and composition analyses for the rainy season of 2017. Results show that the short-term forecasts of PWAFS are characterized by considerable skills for WRWS events in the coastal areas of YHR in view of the object-based diagnostic evaluation, which, however, tend to generate the rain belts with northeast shift phases and weaker intensities. Meantime, the threat score results for WRWS-associated processes show that the model forecasting skill declines sharply as the precipitation intensity increases. Moreover, composition differences of the synoptic-scale thermodynamic characteristics between observations and forecast results are diagnosed to reveal the possible mechanisms of the short-term forecast biases toward WRWS. The zonal westerlies are overestimated in the model, while the southerlies are underestimated in the lower troposphere over coastal areas of YHR, leading to the northeastward shifted shear line and the absent moisture channel associated with the East China Sea at the boundary layer. Attributed to these atmospheric circulation biases, the accumulated warm and moist energy is weaker at the boundary layer, and hence, the short-term forecasts of the rain-belt location for WRWS over the YHR coastal areas have northeast shifting phases with weaker intensities of precipitation in forecasts of the regional business model PWAFS.

A 3D network capture substrate based on poly(lactic-co-glycolic acid) (PLGA) nanofibers was studied and successfully used for high-efficiency cancer cell capture. The arc-shaped glass micropillars were prepared by chemical wet etching and soft lithography. PLGA nanofibers were coupled with micropillars by electrospinning. Given the size effect of the microcolumn and PLGA nanofibers, a three-dimensional of micro-nanometer spatial network was prepared to form a network cell trapping substrate. After the modification of a specific anti-EpCAM antibody, MCF-7 cancer cells were captured successfully with a capture efficiency of 91%. Compared with the substrate composed of 2D nanofibers or nanoparticles, the developed 3D structure based on microcolumns and nanofibers had a greater contact probability between cells and the capture substrate, leading to a high capture efficiency. Cell capture based on this method can provide technical support for rare cells in peripheral blood detection, such as circulating tumor cells and circulating fetal nucleated red cells.

The unmanned swarm system (USS) has been seen as a promising technology, and will play an extremely important role in both the military and civilian fields such as military strikes, disaster relief and transportation business. As the “nerve center” of USS, the unmanned swarm communication system (USCS) provides the necessary information transmission medium so as to ensure the system stability and mission implementation. However, challenges caused by multiple tasks, distributed collaboration, high dynamics, ultra-dense and jamming threat make it hard for USCS to manage limited spectrum resources. To tackle with such problems, the machine learning (ML) empowered intelligent spectrum management technique is introduced in this paper. First, based on the challenges of the spectrum resource management in USCS, the requirement of spectrum sharing is analyzed from the perspective of spectrum collaboration and spectrum confrontation. We found that suitable multi-agent collaborative decision making is promising to realize effective spectrum sharing in both two perspectives. Therefore, a multi-agent learning framework is proposed which contains mobile-computing-assisted and distributed structures. Based on the framework, we provide case studies. Finally, future research directions are discussed.

In this paper, we study the joint problem of multichannel selection and data scheduling for high-frequency (HF) communication under jamming environment. Prior anti-jamming work mainly discussed fixed transmission time and considered saturated scenarios in which the agent always had packets to transmit. But HF dynamic spectrum environment and time-varying communication demand make traditional anti-jamming methods ineffective. To cope with above challenge, dynamic transmission time and packet scheduling are considered in this manuscript. The transmitter selects the working channel and the number of packets to be transmitted according to current jamming environment and buffer state. Simultaneously, channel diversity which allows the transmitter to select multiple channels to send same packet is also considered to overcome the unreliable and unstable characteristics of HF channel. We formulate the decision making process as a Markov decision process (MDP) and propose an interference-aware reinforcement learning algorithm. The proposed algorithm combining Q learning with upper confidence bounds for trees (UCT) balances exploration and exploitation of action set. Simulation results show that higher network throughput and less packet loss are obtained by the proposed algorithm.

El presente trabajo tiene como objetivo realizar un estudio comparativo del símbolo de la naturaleza/el mundo rural en las obras de Miguel Delibes y Mo Yan, siendo ambos importantes figuras de la literatura de España y de China. Mediante un análisis a la nature writing de sus obras, que engloba la construcción del espacio literario, el lenguaje y la función del paisaje de la naturaleza/el mundo rural, trataremos de sacar las similitudes entre sus creaciones literarias y las diferencias en el significado de la naturaleza/el mundo rural para ambos autores: siendo para Delibes es el destino del ser humano, mientras que para Mo es el camino de búsqueda de la esencia de sí mismo.

In this paper, we study joint relay selection and the power control optimization problem in an anti-jamming relay communication system. Considering the hierarchical competitive relationship between a user and jammer, we formulate the anti-jamming problem as a Stackelberg game. From the perspective of game, the user selects relay and power strategy firstly which acts as the leader, while the jammer chooses power strategy then that acts as follower. Moreover, we prove the existence of Stackelberg equilibrium. Based on the Q-learning algorithm and multi-armed bandit method, a hierarchical joint optimization algorithm is proposed. Simulation results show the user’s strategy selection probability and the jammer’s regret. We compare the user’s and jammer’s utility under the proposed algorithm with a random selection algorithm to verify the algorithm’s superiority. Moreover, the influence of feedback error and eavesdropping error on utility is analyzed.

Here is reported a fluorescent biosensor for glucose detection based on water-soluble and pH-responsive silicon nanodots. The silicon nanodots were prepared using a facile hydrothermal method. The advantages of using the silicon nanodots as glucose sensor are twofold. Firstly, the fluorescence of silicon nanodots was quenched by hydrogen peroxide that was produced from glucose oxidation. Secondly, the fluorescence of silicon nanodots was highly sensitive to gluconic acid that was also produced by glucose oxidation. Our results show that this method detected glucose as low as 0.54 μM with a good selectivity and allowed the determination of glucose in serum samples. This method is also simple, rapid, low-toxic and low-cost, thereby hold high application potential for biological assays. [ABSTRACT FROM AUTHOR]

Reservoir model parameters generally have very large uncertainty ranges, and need to be calibrated by history matching (HM) available production data. Properly assessing the uncertainty of production forecasts (e.g., with an ensemble of calibrated models that are conditioned to production data) has a direct impact on business decision making. It requires performing numerous reservoir simulations on a distributed computing environment. Because of the current low-oil-price environment, it is demanding to reduce the computational cost of generating multiple realizations of history-matched models without compromising forecasting quality. To solve this challenge, a novel and more efficient optimization method (referred to as SVR-DGN) is proposed in this paper, by replacing the less accurate linear proxy of the distributed Gauss-Newton (DGN) optimization method (referred to as L-DGN) with a more accurate response-surface model of support vector regression (SVR). Resembling L-DGN, the proposed SVR-DGN optimization method can be applied to find multiple local minima of the objective function in parallel. In each iteration, SVR-DGN proposes an ensemble of search points or reservoir-simulation models, and the flow responses of these reservoir models are simulated on high-performance-computing (HPC) clusters concurrently. All successfully simulated cases are recorded in a training data set. Then, an SVR proxy is constructed for each simulated response using all training data points available in the training data set. Finally, the sensitivity matrix at any point can be calculated analytically by differentiating the SVR models. SVR-DGN computes more-accurate sensitivity matrices, proposes better search points, and converges faster than L-DGN. The quality of the SVR proxy is validated with a toy problem. The proposed method is applied to a real field HM example of a Permian liquid-rich shale reservoir. The uncertain parameters include reservoir static properties, hydraulic-fracture properties, and parameters defining relative permeability curves. The performance of the proposed SVR-DGN optimization method is compared with the L-DGN optimizer and the hybrid Gauss-Newton with a direct-pattern-search (GN-DPS) optimizer, using the same real field example. Our numerical tests indicate that the SVR-DGN optimizer can find better solutions with smaller values of the objective function and with a less computational cost (approximately one-third of L-DGN and 1/30 of GN-DPS). Finally, the proposed method is applied to generate multiple conditional realizations for the uncertainty quantification of production forecasts. [ABSTRACT FROM AUTHOR]

Although it is possible to apply traditional optimization algorithms together with the randomized-maximum-likelihood (RML) method to generate multiple conditional realizations, the computation cost is high. This paper presents a novel method to enhance the globalsearch capability of the distributed-Gauss-Newton (DGN) optimization method and integrates it with the RML method to generate multiple realizations conditioned to production data synchronously. RML generates samples from an approximate posterior by minimizing a large ensemble of perturbed objective functions in which the observed data and prior mean values of uncertain model parameters have been perturbed with Gaussian noise. Rather than performing these minimizations in isolation using large sets of simulations to evaluate the finite-difference approximations of the gradients used to optimize each perturbed realization, we use a concurrent implementation in which simulation results are shared among different minimization tasks whenever these results are helping to converge to the global minimum of a specific minimization task. To improve sharing of results, we relax the accuracy of the finite-difference approximations for the gradients with more widely spaced simulation results. To avoid trapping in local optima, a novel method to enhance the global-search capability of the DGN algorithm is developed and integrated seamlessly with the RML formulation. In this way, we can improve the quality of RML conditional realizations that sample the approximate posterior. The proposed work flow is first validated with a toy problem and then applied to a real-field unconventional asset. Numerical results indicate that the new method is very efficient compared with traditional methods. Hundreds of data-conditioned realizations can be generated in parallel within 20 to 40 iterations. The computational cost (central-processing-unit usage) is reduced significantly compared with the traditional RML approach. The real-field case studies involve a history-matching study to generate history-matched realizations with the proposed method and an uncertainty quantification of production forecasting using those conditioned models. All conditioned models generate production forecasts that are consistent with real-production data in both the history-matching period and the blind-test period. Therefore, the new approach can enhance the confidence level of the estimated-ultimate-recovery (EUR) assessment using production-forecasting results generated from all conditional realizations, resulting in significant business impact. [ABSTRACT FROM AUTHOR]

It is extremely challenging to design effective assisted-history-matching (AHM) methods for complex geological models with discrete-facies types. One of the difficulties is the irregular and nonsmooth nature of the data-mismatch function that needs to be minimized, because of either numerical noise on simulation results or nonsmooth reparameterization. In this paper, a parallelized direct-pattern-search (DPS) approach with auto-adaptive pattern- size updating is developed to guarantee the convergence of the data-mismatch minimization, even when the objective function is nonsmooth because of numerical noise. A trust-region variant of the Gauss-Newton (GN) or quasi-Newton (QN) method is effectively combined with the noise-insensitive DPS method to enhance its performance by exploiting any available smoothness features of the objective function. The new approach is first validated by a linear toy problem and a nonlinear toy problem where artificial numerical noise is introduced. Then, it is applied to a synthetic case and a real field case for history matching of channelized-turbidite reservoirs with three facies types. The model parameters subject to AHM include principal component analysis (PCA) coefficients, which automatically reconstruct the facies indicators and permeability, porosity, and net-to-gross maps. Other matching parameters such as aquifer strength and fault transmissibility are also included. Numerical tests indicate that the hybrid algorithms perform better than the traditional QN line-search algorithms and the original Hooke-Jeeves DPS algorithm (Hooke and Jeeves 1961). The hybrid algorithms either can converge to a satisfactory solution with the same accuracy using lower cost or find a better solution with the same cost, especially for cases where adjoint derivatives are unavailable and numerical noise is unavoidable from reservoir simulation. The GN-DPS algorithm performs the best among all tested algorithms. The history-matched reservoir models obtained with the new AHM approach (GN-DPS combined with pluri-PCA) honor the production measurements with good accuracy. For both the synthetic and real cases, the history-matched reservoir models preserve geological realism. [ABSTRACT FROM AUTHOR]

Objective: To report the outcome of a patient who developed pseudoaneurysms and compartment syndrome after a Deinagkistrodon acutus snakebite. Case report: A 61-year-old man, bitten by Deinagkistrodon acutus in his left forearm, came to the hospital eight hours after the bite. Despite the use of antivenom and supportive therapy, the patient developed compartment syndrome of the left forearm, the tissue pressure was elevated and fasciotomy was arranged. During the initial surgery, part of the necrotic tissues was removed. Moreover, two pseudoaneurysms of the ulnar artery were identified at the second debridement and the pseudoaneurysms were removed during this surgery. The patient went through a total of four surgeries, recovered and was eventually discharged from the hospital. Conclusion: A snake bite by Deinagkistrodon acutus may be accompanied by pseudoaneurysms and increased intracompartmental pressure. [ABSTRACT FROM AUTHOR]

A novel route for the total synthesis of E-carotene is described. The synthesis is based on a condensation between a-cyclocitral and diethyl [(2E)-3-methoxy-2-methylprop-2-en-1-yl]phosphonate to give a C14 enol ether, hydrolysis of the C14-enol ether to a give a C14 aldehyde, and a modified Wittig-Horner reaction of the C15 phosphonate from the C14 aldehyde and a C10 triene dialdehyde to give E-carotene. The synthetic steps are easily performed and are practical for largescale production. [ABSTRACT FROM AUTHOR]

The article describes the implementation of a new optimization algorithm on the basis of a quadratic interpolation model fro the maximization of objective function. It indicates that the new algorithm does not need a gradient calculation with an adjoint approach but use an approximate gradient. It notes that the algorithm represents a key modification of an optimization algorithm.

We have developed a novel immuno-sensor applied to protein detection based on exonuclease III (Exo III)-induced signal amplification, multiplex binding of the biotin-streptavidin system and the fluorescence quenching ability of graphene oxide. [ABSTRACT FROM AUTHOR]

A colorimetric platform for influenza A virus detection was developed by using the high efficiency of enzymatic catalysis and the reduction of gold ions with hydrogen peroxide. Aptamer-functionalized magnetic microparticles were synthesized to capture the influenza A virus. This was followed by the binding of ConA-GOx-AuNPs to the H3N2 virus through the ConA-glycan interaction. The sandwich complex was subsequently dispersed in glucose solution to trigger an enzymatic reaction to produce hydrogen peroxide, which controlled the growth of gold nanoparticles and produced colored solutions. The determination of H3N2 concentration was realized by comparing the two differently colored gold nanoparticles. This method could detect the target virus as low as 11.16 μg ml−1. Furthermore, it opens new opportunities for sensitive and colorimetric detection of viruses and proteins. [ABSTRACT FROM AUTHOR]

Background and purpose: Free flap has become the main way of reconstruction after surgery for head and neck tumor. Vascular crisis is easy to cause skin flap necrosis, and hypercoagulability is the main cause of vascular crisis. This study explored the factors influencing postoperative hypercoagulability of free flap reconstruction for head and neck tumor, and provided reference for the prevention and treatment of hypercoagulability. Methods: A retrospective analysis was conducted according to the medical records of 243 patients admitted to Department of Otolaryngology, Second Affiliated Hospital of Fujian Medical University from Apr. 2017 to Jul. 2020 who underwent free flap reconstruction for head and neck tumor. The patients were divided into the hypercoagulable group and the non-hypercoagulable group according to whether postoperative hypercoagulable state occurred, and the incidence of postoperative hypercoagulable state and related influencing factors were statistically analyzed. Results: Among the 243 patients, 128 patients had postoperative hypercoagulability, and the incidence was 52.7% (128/243), including 73.4% (94/128) of two postoperative coagulation abnormalities, 21.1% (27/128) of three abnormalities and 5.5% (7/128) of four abnormalities. Results of single factor analysis showed that gender, age, alcoholism, diabetes, tumor stage, surgical repair, intraoperative blood loss, intraoperative blood transfusion, operative time, postoperative leukocyte, postoperative triglyceride, postoperative high-density lipoprotein and postoperative Ca 2+ were the possible influencing factors of postoperative hypercoagulability (all P

Objectives: The objective of this study is to evaluate the diagnosis and prognosis of malignant mesothelioma of the tunica vaginalis testis through an additional 6 patients with urogenital mesothelioma. Methods: Six patients with urogenital mesothelioma who underwent adequate surgical procedures and histopathologic analysis from 1990 to 2009 were identified and retrospectively reviewed. Results: Six patients between the ages of 26 and 78 years with urogenital mesothelioma, 5 of which originated in the scrotum and 1 in the spermatic cord. Histopathologic analysis showed that CK5/6 and calretinin were positive in all cases, 5 cases were positive for vimentin, and 1 case showed focal weak positive reaction with MOC3, but none of the cases stained for CEA or CD15. The overall recurrence rate of urogenital mesothelioma after surgery was 5/6, including local recurrences and fatalities due to tumour. Conclusions: In cases of mesothelioma of the tunica vaginalis testis, the histopathologic markers we chose helped confirm the histopathological diagnosis; adequate surgical procedures are typically not curative, and this tumour is often fatal. [ABSTRACT FROM AUTHOR]