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Physical unclonable function (PUF), a hardware that can extract the differences of the same implementations and provide unique secret keys without the utilization of non-volatile memory, is regarded as a promising security primitive in the near future. Ring Oscillator (RO) PUF is one of its easy silicon implementations, which exploits the frequency difference between a pair of structurally identical ring oscillators. However, a large number of ROs must be constructed if multiple stable output bits are required, which means unacceptable area overhead for lightweight applications. To solve this problem, configurable ROs using multiplexers and different delay units were proposed in previous papers. Unfortunately, most of them take advantage of the specific structure of a certain type of field-programmable gate arrays (FPGAs), thus not cost-saving for application-specific integrated circuit (ASIC). In this paper, we propose a configurable RO using only two hybrid logic gates in each stage for ASIC, which costs less area and power compared with previous proposals. Experiment on 50 FPGAs and one self-designed printed circuit board demonstrates satisfactory uniformity and uniqueness of this novel RO PUF. Furthermore, our proposal is proved to be reliable in a wide variety of environment conditions.

Rock failure phenomena are accompanied by abundant energy variation, and the energy dissipation can explain the dynamic mechanical characteristics of the rock. In this study, a series of granite specimens (a total of 60) with different aspect ratios were dynamically loaded by a split Hopkinson pressure bar (SHPB) to explain the energy dissipation and the rock-crushing degree under dynamic load. A new index, namely energy time density (wtd), is proposed to evaluate the energy dissipation considering the time factor. The relationships between strain rate, energy time density, and specific energy absorption are analyzed. A metric (Ku) is defined to describe the degree of rock fragmentation quantitatively. The correlations of fractal dimension and Ku with different impact pressures are compared. It was concluded that there is a noticeable peak point in the energy time density curve. The energy time density of the stress equilibrium point is three times that of the peak point. The energy time density declines after the peak point, then the energy consumption density tends to be stable. The linear relationship between strain rate and peak point energy time density is stronger. The new index can describe energy dissipation well under dynamic loading. In addition, the experimental results indicate that the degree of crush Ku can describe the degree of crush, and the effect of fractal dimension to quantify the fracture characteristics of the rocks is less good in this test. The crushing degree of rocks increases with the increase of strain rate. Furthermore, the prediction effect of energy time density is better than that of strain rate about Ku.

Purpose: This study aims to evaluate the predictive efficacy of the C-reactive protein/albumin ratio (CAR), a cost-effective, easily accessible, and reproducible biomarker obtained from standard blood tests, in forecasting acute kidney injury (AKI) among patients undergoing acute pancreatitis (AP). Considering that changes in the CAR are associated with AKI incidence in AP cases, this work aims to explore whether CAR can be used as the innovative, inflammation-based diagnostic marker for AKI in AP patients. Methods: The current retrospective cohort study consecutively enrolled AP patients admitted to First College of Clinical Medical Science of China Three Gorges University during the period from January 2019 to October 2023. Data were extracted systematically in electronic medical records from these hospitalized individuals, including baseline demographic and clinical characteristics. To ascertain the association of the CAR level with the development of AKI, we carried out multivariate logistic regression, adjusting for potential confounders. These confounders were initially identified through univariate regression. Furthermore, the potential effect modifiers in the relationship between CAR and AKI occurrence were explored by stratified logistic regression. Results: Totally, 1514 AP were recruited, including 257 (16.9%) with AKI. CAR was positively correlated with AKI. When adjusting for potential confounders, the AKI risk in patients in the upper CAR tertile (2.628– 22.994) increased by 83% relative to those in lower tertile (0.05– 0.289) (OR 1.83, 95% CI 1.13– 2.96, P = 0.013). The AKI risk tended to increase according to the increasing CAR tertile (P for trend = 0.013). No significant interactions were observed among subgroups based on age, sex, BMI, admission to ICU, hypertension, DM, chronic obstructive pulmonary disease, severity of AP, etiology of AP, demand for CRRT, mechanical ventilation, and blood transfusion (all P > 0.05). Conclusion: A higher CAR is significantly related to the higher AKI incidence in AP patients in the Chinese population. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs).sup.1-3 are known for their specific interactions with gas molecules.sup.4,5; this, combined with their rich and ordered porosity, makes them promising candidates for the photocatalytic conversion of gas molecules to useful products.sup.6. However, attempts to use MOFs or MOF-based composites for CO.sub.2 photoreduction.sup.6-13 usually result in far lower CO.sub.2 conversion efficiency than that obtained from state-of-the-art solid-state or molecular catalysts.sup.14-18, even when facilitated by sacrificial reagents. Here we create 'molecular compartments' inside MOF crystals by growing TiO.sub.2 inside different pores of a chromium terephthalate-based MOF (MIL-101) and its derivatives. This allows for synergy between the light-absorbing/electron-generating TiO.sub.2 units and the catalytic metal clusters in the backbones of MOFs, and therefore facilitates photocatalytic CO.sub.2 reduction, concurrent with production of O.sub.2. An apparent quantum efficiency for CO.sub.2 photoreduction of 11.3 per cent at a wavelength of 350 nanometres is observed in a composite that consists of 42 per cent TiO.sub.2 in a MIL-101 derivative, namely, 42%-TiO.sub.2-in-MIL-101-Cr-NO.sub.2. TiO.sub.2 units in one type of compartment in this composite are estimated to be 44 times more active than those in the other type, underlining the role of precise positioning of TiO.sub.2 in this system. Investigation of a chromium-based metal-organic framework shows that the location of added TiO.sub.2 inside specific mesopores strongly affects the ability of the material to catalyse photoreduction of CO.sub.2., Author(s): Zhuo Jiang [sup.1] , Xiaohui Xu [sup.1] , Yanhang Ma [sup.2] , Hae Sung Cho [sup.2] , Deng Ding [sup.1] , Chao Wang [sup.1] , Jie Wu [sup.1] , [...]

Counterparty credit risk (CCR) is a significant risk factor that financial institutions have to consider in today's context, and the COVID-19 pandemic and military conflicts worldwide have heightened concerns about potential default risk. In this work, we investigate the changes in the value of financial derivatives due to counterparty default risk, i.e., total value adjustment (XVA). We perform the XVA for multi-asset option based on the multivariate Carr–Geman–Madan–Yor (CGMY) processes, which can be applied to a wider range of financial derivatives, such as basket options, rainbow options, and index options. For the numerical methods, we use the Monte Carlo method in combination with the alternating direction implicit method (MC-ADI) and the two-dimensional Fourier cosine expansion method (MC-CC) to find the risk exposure and make value adjustments for multi-asset derivatives. [ABSTRACT FROM AUTHOR]

Developing an efficient, low-cost and stable catalyst to activate peroxymonosulfate (PMS) for pollutant degradation is crucial in environmental remediation. Herein, Co1Fe1 layered double hydroxide (Co1Fe1-LDH) was in situ loaded on biochar (BC) derived from rape straw for sulfamethoxazole (SMX) degradation via activating PMS. It could be found that the optimal catalyst (BC/Co1Fe1-LDH-4) exhibited the highest SMX degradation efficiency of 94.8% within 5 min reaction, far more than pristine Co1Fe1-LDH (58.5%), which might be ascribed to the synergistic effects between Co1Fe1-LDH and BC during the reaction. For one thing, BC itself participated in the catalytic degradation reaction as an activator and made the catalyst have excellent adsorption and degradation performance. For another, BC as a carrier not only effectively inhibited the agglomeration of Co1Fe1-LDH to increase the active sites, but also accelerated the Co2+/Co3+ and Fe2+/Fe3+ cycles to reduce the leaching of metal ions. Meanwhile the leaching of trace metal ions also promoted the degradation of SMX to a certain extent, indicating that the catalytic mechanism was a combination of homogeneous and heterogeneous catalysis, and the latter was dominant. The quenching trials, electron paramagnetic resonance (EPR) and electrochemical measurements implied that the radical and non-radical processes were involved in the reaction, where SO4˙−, ˙OH and O2˙− were the main radical species to drive the radical process, and 1O2 and direct electron transfer were responsible for the non-radical process. In addition, the possible SMX degradation pathways were reasonably proposed by high-performance liquid chromatography-mass spectrometry (HPLC-MS) tests and the SMX mineralization degree was provided through total organic carbon (TOC) measurements. This present work provides new insight into the construction of highly efficient PMS activation catalysts for environmental wastewater treatment. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, many institutions have announced that their counterparties are struggling to fulfill contracts. Therefore, it is necessary to consider the counterparty default risk when pricing options. After the 2008 financial crisis, a variety of value adjustments have been emphasized in the financial industry. The total value adjustment (XVA) is the sum of multiple value adjustments, which is also investigated in many stochastic models, such as the Heston [B. Salvador and C. W. Oosterlee, Appl. Math. Comput. 391, 125489 (2020)] and Bates [L. Goudenège et al., Comput. Manag. Sci. 17, 163–178 (2020)] models. In this work, a widely used pure jump Lévy process, the Carr–Geman–Madan–Yor process has been considered for pricing a Bermudan option with various value adjustments. Under a pure jump Lévy process, the value of derivatives satisfies a fractional partial differential equation (FPDE). Therefore, we construct a method that combines Monte Carlo with a finite difference of FPDE to find the numerical approximation of exposure and compare it with the benchmark Monte Carlo simulation and Fourier-cosine series method. We use the discrete energy estimate method, which is different from the existing works, to derive the convergence of the numerical scheme. Based on the numerical results, the XVA is computed by the financial exposure of the derivative value. [ABSTRACT FROM AUTHOR]

A 56-year-old man receiving rituximab who had months of neurologic symptoms was found to have Jamestown Canyon virus in cerebrospinal fluid by clinical metagenomic sequencing. The patient died, and postmortem examination revealed extensive neuropathologic abnormalities. Deep sequencing enabled detailed characterization of viral genomes from the cerebrospinal fluid, cerebellum, and cerebral cortex. [ABSTRACT FROM AUTHOR]

Summary: The problem of domain aiming control is formulated for a controlled stochastic nonlinear system, which involves regularity of the solution to the resulting closed‐loop stochastic system. To begin with, an extended existence and uniqueness theorem for stochastic differential equations with local Lipschitz coefficients is proven by using a Lyapunov‐type function. A Lyapunov‐based sufficient condition on nonregularity is also given. The notions of domain recurrence and residence time for stochastic nonlinear systems are introduced, and various criteria for the recurrence and nonrecurrence relative to a bounded open domain or an unbounded domain are provided. Furthermore, upper bounds of expectation and moment‐generating function of the residence time are derived. In particular, a connection between the mean residence time and a Dirichlet problem is investigated and illustrated with a numerical example. Finally, the problem of domain aiming control is considered for certain types of nonlinear and linear stochastic systems. Several examples are provided to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs)1–3 are known for their specific interactions with gas molecules4,5; this, combined with their rich and ordered porosity, makes them promising candidates for the photocatalytic conversion of gas molecules to useful products6. However, attempts to use MOFs or MOF-based composites for CO2 photoreduction6–13 usually result in far lower CO2 conversion efficiency than that obtained from state-of-the-art solid-state or molecular catalysts14–18, even when facilitated by sacrificial reagents. Here we create 'molecular compartments' inside MOF crystals by growing TiO2 inside different pores of a chromium terephthalate-based MOF (MIL-101) and its derivatives. This allows for synergy between the light-absorbing/electron-generating TiO2 units and the catalytic metal clusters in the backbones of MOFs, and therefore facilitates photocatalytic CO2 reduction, concurrent with production of O2. An apparent quantum efficiency for CO2 photoreduction of 11.3 per cent at a wavelength of 350 nanometres is observed in a composite that consists of 42 per cent TiO2 in a MIL-101 derivative, namely, 42%-TiO2-in-MIL-101-Cr-NO2. TiO2 units in one type of compartment in this composite are estimated to be 44 times more active than those in the other type, underlining the role of precise positioning of TiO2 in this system. Investigation of a chromium-based metal–organic framework shows that the location of added TiO2 inside specific mesopores strongly affects the ability of the material to catalyse photoreduction of CO2. [ABSTRACT FROM AUTHOR]

In recent years, fractional partial differential equation (FPDE) has been widely applied in options pricing problems, which better explains many important empirical facts of financial markets. However, the vast majority of the literatures focus on pricing the single asset option under the FPDE framework. In this paper, a two-dimensional FPDE governing the valuation of rainbow options is established, where two underlying assets are assumed to follow independent exponential Lévy processes, and its boundary conditions are determined by solving one-dimensional FPDEs. A second-order accurate finite difference scheme is proposed to discretize the two-dimensional FPDE. Given the block Toeplitz with Toeplitz block structure of the coefficient matrix, a fast preconditioned Krylov subspace method is developed for solving the resulting linear system with O (N log N) computational complexity per iteration, where N is the matrix size. The proposed preconditioner accelerates the convergence of the iterative method with theoretical analysis. Numerical examples are given to demonstrate the accuracy and efficiency of our proposed numerical methods. [ABSTRACT FROM AUTHOR]

In this paper, almost sure exponential stability and pth moment exponential stability of stochastic cellular neural networks with mixed delays are investigated. Employing the methods of stochastic analysis, the Lyapunov’s method, and useful inequality techniques, a sufficient condition ensuring the almost sure exponential stability and pth moment exponential stability is obtained. Two examples are given to illustrate this sufficient condition. [ABSTRACT FROM AUTHOR]

Abstract: The National Weather Service (NWS) forecasts floods at approximately 3,600 locations across the United States (U.S.). However, the river network, as defined by the 1:100,000 scale National Hydrography Dataset‐Plus (NHDPlus) dataset, consists of 2.7 million river segments. Through the National Flood Interoperability Experiment, a continental scale streamflow simulation and forecast system was implemented and continuously operated through the summer of 2015. This system leveraged the WRF‐Hydro framework, initialized on a 3‐km grid, the Routing Application for the Parallel Computation of Discharge river routing model, operating on the NHDPlus, and real‐time atmospheric forcing to continuously forecast streamflow. Although this system produced forecasts, this paper presents a study of the three‐month nowcast to demonstrate the capacity to seamlessly predict reach scale streamflow at the continental scale. In addition, this paper evaluates the impact of reservoirs, through a case study in Texas. Validation of the uncalibrated model using observed hourly streamflow at 5,701 U.S. Geological Survey gages shows 26% demonstrate PBias ≤ |25%|, 11% demonstrate Nash‐Sutcliffe Efficiency (NSE) ≥ 0.25, and 6% demonstrate both PBias ≤ |25%| and NSE ≥ 0.25. When evaluating the impact of reservoirs, the analysis shows when reservoirs are included, NSE ≥ 0.25 for 56% of the gages downstream while NSE ≥ 0.25 for 11% when they are not. The results presented here provide a benchmark for the evolving hydrology program within the NWS and supports their efforts to develop a reach scale flood forecasting system for the country. [ABSTRACT FROM AUTHOR]