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Aiming at the problem that complex security primitives in existing schemes were not suitable for resource-constrained IoT devices, a lightweight efficient anonymous identity authentication protocol for IoT devices was designed based on physical unclonable function (PUF).Through the formal security model and ProVerif tool, it was proved that the protocol satisfies 13 security properties such as information confidentiality, integrity, un-traceability, and forward/backward secrecy.Compared with existing relevant protocols, the computing overhead of the protocol on the device side and the server side is 0.468 ms and 0.072 ms respectively, and the device storage and communication overheads are 256 bit and 896 bit respectively, which is highly suitable for lightweight IoT devices with limited resources.

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]