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ObjectiveIn intensive care units (ICUs), carbapenem-resistant Enterobacterales (CRE) pose a significant threat. We aimed to examine the distribution, epidemiological characteristics, and risk factors for CRE positivity in ICUs.Materials and methodsThis cross-sectional study was conducted in 96 ICUs of 78 hospitals in Henan Province, China. The clinical and microbiological data were collected. A multivariable logistic regression model was used to analyze the risk factors for CRE positivity.ResultsA total of 1,009 patients were enrolled. There was a significant difference in CRE positive rate between pharyngeal and anal swabs (15.16 vs. 19.13%, P < 0.001). A total of 297 carbapenem-resistant Klebsiella pneumoniae (CR-KPN), 22 carbapenem-resistant Escherichia coli (CR-ECO), 6 carbapenem-resistant Enterobacter cloacae (CR-ECL), 19 CR-KPN/CR-ECO, and 2 CR-KPN/CR-ECL were detected. Klebsiella pneumoniae carbapenemase (KPC), New Delhi metallo-beta-lactamase (NDM), and a combination of KPC and NDM were detected in 150, 9, and 11 swab samples, respectively. Multivariable logistic regression analysis determined length of ICU stay, chronic neurological disease, transfer from other hospitals, previous infection, and history of antibiotics exposure as independent risk factors for CRE positivity. Age and cardiovascular diseases were independent risk factors for mixed infections of CRE. The occurrence of CRE in secondary and tertiary hospitals was 15.06 and 25.62%, respectively (P < 0.05). Patients from tertiary hospitals had different clinical features compared with those from secondary hospitals, including longer hospital stays, a higher rate of patients transferred from other hospitals, receiving renal replacement therapy, exposure to immunosuppressive drugs, use of antibiotics, and a higher rate of the previous infection.ConclusionIn ICUs in Henan Province, CRE positive rate was very high, mostly KPC-type CR-KPN. Patients with prolonged ICU stay, chronic neurological disease, transfer from other hospitals, previous infection, and history of antibiotic exposure are prone to CRE. Age and cardiovascular diseases are susceptibility factors for mixed infections of CRE. The CRE positive rate in tertiary hospitals was higher than that in secondary hospitals, which may be related to the source of patients, antibiotic exposure, disease severity, and previous infection.

In this paper, a priori estimate for a linear third pseudoparabolic operator with bound is established, and applying the above result, the existence and uniqueness theorem of solutions for a class of nonlinear pseudoparabolic equations is obtained with the help of the homeomorphism method and the initial value method. Furthermore, an existence and uniqueness theorem of the semilinear equation is obtained as a corollary.

The creep problems are often involved in soil under cyclic loading, and its behaviors of soil under cyclic loading sparks many arguments in current research field. To propose one new model to demonstrate these creep behaviors of soil under cyclic loading, the cyclic loading was simplified equivalently, and the elastic-viscoplastic model (EVPM) for soil under cyclic loading was established based on the Bingham model. The yield criterion for soil under cyclic loading with constant amplitude was proposed following the simplified load. A constitutive equation based on the EVPM was constructed by using the flow criterion related to the yield criterion. Meanwhile, the parameters of EVPM were identified and discussed. In addition, the case analysis of the EVPM was also performed. The results indicate that the stable and destructive creep behaviors of soil under cyclic loading could be well described by the recommended EVPM, and the obtained parameters in the model exhibited a clear regularity with the increase of dynamic stress amplitude. Besides, the established model could be selected to predict the stable and destructive creep behavior of soil under cyclic loading.

The massive multiple-input multiple-output (MIMO) technology is one of the core technologies of 5G, which can significantly improve spectral efficiency. Because of the large number of massive MIMO antennas, the computational complexity of detection has increased significantly, which poses a significant challenge to traditional detection algorithms. However, the use of deep learning for massive MIMO detection can achieve a high degree of computational parallelism, and deep learning constitutes an important technical approach for solving the signal detection problem. This paper proposes a deep neural network for massive MIMO detection, named Multisegment Mapping Network (MsNet). MsNet is obtained by optimizing the prior detection networks that are termed as DetNet and ScNet. MsNet further simplifies the sparse connection structure and reduces network complexity, which also changes the coefficients of the residual structure in the network into trainable variables. In addition, this paper designs an activation function to improve the performance of massive MIMO detection in high-order modulation scenarios. The simulation results show that MsNet has better symbol error rate (SER) performance and both computational complexity and the number of training parameters are significantly reduced.

Background: Glaucoma is a multifactorial optic neuropathy progressively characterized by structural loss of Retinal Ganglion Cells (RGCs) and irreversible loss of vision. High Intraocular Pressure (HIOP) is a high-risk factor for glaucoma. It has been reported that the mechanisms of the loss of RGCs are explored in-depth after acute HIOP injury, such as apoptosis, autophagy, and necrosis. However, pyroptosis, a novel type of pro-inflammatory cell programmed necrosis, is rarely reported after HIOP injury. Research studies also showed that melatonin (MT) possesses substantial anti-inflammatory properties. However, whether melatonin could alleviate retinal neuronal death, especially pyroptosis, by HIOP injury is still unclear. Objective: This study explored pyroptosis of retinal neurons and the effects of melatonin in preventing retinal neurons from pyroptosis after acute HIOP injury. Methods: An acute HIOP model of rats was established by increasing the IOP followed by reperfusion. Western Blot (WB) was adopted to detect molecules related to pyroptosis at the protein level, such as GSDMD, GASMDp32, Caspase-1, and caspase-1 p20, and the products of inflammatory reactions, such as IL -18 and IL-1β. At the same time, immunofluorescence (IF) was used to co-localize caspase-1 with retinal neurons to determine the position of caspase-1 expression. Morphologically, ethidium homodimer III staining, a method commonly used to evaluate cell death, was carried out to stain dead cells. Subsequently, Lactate Dehydrogenase (LDH) cytotoxicity assay kit was used to quantitatively analyze the LDH released after cell disruption. Results: The results suggested that pyroptosis played a vital role in retinal neuronal death, especially in the Ganglion Cell Layer, by acute HIOP injury and peaked at 6h after HIOP injury. Furthermore, it was found that melatonin (MT) might prevent retinal neurons of pyroptosis via NF-κ B/NLRP3 axis after HIOP injury in rats. Conclusion: Melatonin treatment might be considered a new strategy for protecting retinal neurons against pyroptosis following acute HIOP injury.

In this paper, we will present a horizontal attack on SM9 signature generation. The horizontal attack can make use of the information from multiple locations on one curve of SM9 signature generation to exploit the secret key. Since only one curve is needed in this attack, the conventional countermeasures like message blinding and key randomization would not work. We accomplished the security evaluation of SM9 signature generation on Sasebo-GII. The experiment results show that a vulnerable realization could leak the information of all key bits.

Aiming at the nonlinear equation problems of time difference of arrival (TDOA) passive location, this paper proposes the improved grey wolf optimization (IGWO) algorithm. By adding the individual learning strategy to the standard grey wolf optimization (GWO) algorithm, and taking trigonometric function nonlinear convergence factor to balance the exploration ability and development ability, the proposed algorithm can search optimal coordinates of TDOA passive location. Simulation results show that the modified algorithm has stable performance and simple controlling parameters. The algorithm can quickly approach the global optimal solution with the small scale of wolf pack, and has faster convergence speed and higher locating precision.

Elliptic Curve Cryptography (ECC) is becoming widely deployed in embedded cryptographic devices because of the reduced number of key bits. However, the side-channel attacks especially simple side-channel analysis (SPA) can obtain secret keys by measuring power consumption. To resist this attack there appear a number of countermeasures such as Montgomery ladder and double-and-add-always algorithm. This paper proposes a new simple power analysis attack to these countermeasures by distinguishing the conditional subtraction of Montgomery modular multiplication (MMM). Experimental results on smart cards demonstrate that this attack method can retrieve secret keys easily in several seconds using one power trace. Several countermeasures that can resist this kind of SPA attack are also demonstrated in this paper.

Dynamic password technology is widely utilized for identity authentication, which depends on using hash functions, such as SM3. And SM3 hash algorithm is based on the mixing of different group operations, such as XOR and addition modulo 232. In this paper, we present two original first-order differential power analysis attacks on dynamic password token based on SM3 algorithm. The two proposed DPA attacks are against XOR and addition modulo 232 operation respectively. Experimental results show that dynamic password token based on SM3 algorithm is vulnerable to side channel attacks, no matter implemented in software or hardware. We also provide a masked implementation of the algorithm, which is designed to avoid those proposed attacks.

As the critical component of concentrating photovoltaic module, secondary concentrators can be effective in increasing the acceptance angle and incident light, as well as improving the energy uniformity of focal spots. This paper presents a design of transmission-type secondary microprism for dense array concentrating photovoltaic module. The 3-D model of this design is established by Solidworks and important parameters such as inclination angle and component height are optimized using Zemax. According to the design and simulation results, several secondary microprisms with different parameters are fabricated and tested in combination with Fresnel lens and multi-junction solar cell. The sun-simulator IV test results show that the combination has the highest output power when secondary microprism height is 5mm and top facet side length is 7mm. Compared with the case without secondary microprism, the output power can improve 11% after the employment of secondary microprisms, indicating the indispensability of secondary microprisms in concentrating photovoltaic module.

At present, the conversion efficiency of high concentrated photovoltaic modules is about 30%, most of the solar energy is converted into heat, which will result in solar cell temperature rise and subsequent module efficiency decrease. For existing module with large solar cell, the heat source is concentrated and additional cooling fins must be used, resulting in high system complexity and cost rise. In order to lower the cost of photovoltaic, we developed distributed cooling type module with simple structure. This paper depicts a distributed cooling design for high concentrated photovoltaic module, as well as the thermal simulation of this design with analysis software. Module prototype was also made to test the actual effect. The final outdoor results showed high consistency with the simulation results. The chip temperature can be lower than 45℃ and the module outdoor working efficiency is higher than 26% ，and lower temperature provide a guarantee of long-term reliability to module packaging material.

HMAC algorithm is one of the most famous keyed hash functions, and widely utilized. And SM3 is the only standard hash algorithm of China. However, most cryptographic algorithms implementations are vulnerable against side channel attacks. But specific side channel attacks on HMAC-SM3 have not been given so far. This paper presents a first-order DPA attack on HMAC-SM3. HMAC-SM3 hash algorithm is based on the mixing of different algebraic operations, such as XOR and addition modulo 2, thus the proposed DPA attack is mainly against these basic group operations. Experimental results are given by attacking an implementation of HMAC-SM3 in a smart card, which demonstrate the practicability of such attacks described in this paper. Keywords—HMAC;SM3; DPA

Dynamic password technology is one of the most widely utilized methods for identity authentication. The security of dynamic password system depends on the cryptographic strength of the underlying hash function. And SM3 is the only standard hash algorithm of China. However, most cryptographic algorithm implementations are vulnerable against side channel attacks. But specific side channel attacks on dynamic password token based on SM3 hash function have not been given so far. This paper presents a differential power analysis attack on dynamic password token based on SM3 algorithm. SM3 hash algorithm is based on the mixing of different algebraic operations, such as XOR and addition modulo 232, thus the proposed DPA attack is mainly against these basic group operations. Experimental results are given by attacking an implementation of generating dynamic password using SM3 algorithm in a smart card, which demonstrate the feasibility of such attacks described in this paper. Keywords—Dynamic password token; SM3; DPA

In this paper, we will present a chosen-plaintext method of CPA on SM4 block cipher. This attack consists of a chosen-plaintext method and a transformed CPA attack. The chosen-plaintext method is used to decrease the computation complexity to guess the round register value and the transformed CPA attack is introduced to improve the effect of CPA attack. We accomplished hardware implement on Sasebo-Gii and power analysis, whose result proved that it takes 5000 traces to recover the key successfully by our method, while the normal CPA method needs 270000 traces.