CARE: Confidence-rich Autonomous Robot Exploration using Bayesian Kernel Inference and Optimization

In this paper, we consider improving the efficiency of information-based autonomous robot exploration in unknown and complex environments. We first utilize Gaussian process (GP) regression to learn a surrogate model to infer the confidence-rich mutual information (CRMI) of querying control actions, then adopt an objective function consisting of predicted CRMI values and prediction uncertainties to conduct Bayesian optimization (BO), i.e., GP-based BO (GPBO). The trade-off between the best action with the highest CRMI value (exploitation) and the action with high prediction variance (exploration) can be realized. To further improve the efficiency of GPBO, we propose a novel lightweight information gain inference method based on Bayesian kernel inference and optimization (BKIO), achieving an approximate logarithmic complexity without the need for training. BKIO can also infer the CRMI and generate the best action using BO with bounded cumulative regret, which ensures its comparable accuracy to GPBO with much higher efficiency. Extensive numerical and real-world experiments show the desired efficiency of our proposed methods without losing exploration performance in different unstructured, cluttered environments. We also provide our open-source implementation code at https://github.com/Shepherd-Gregory/BKIO-Exploration.Comment: Full version for the paper accepted by IEEE Robotics and Automation Letters (RA-L) 2023. arXiv admin note: text overlap with arXiv:2301.0052

UBE2R2-AS1, as a prognostic marker of gastric cancer, promotes the malignant phenotype of gastric cancer cells

Background and Objectives. This study aimed to unveil the potential of UBE2R2-AS1 dysregulation in gastric cancer. In addition, its biological function was assessed. Materials and Methods. UBE2R2-AS1 expression was predicted in the ENCORI database. Paired gastric cancer and noncancerous tissues were collected. UBE2R2-AS1 expression was confirmed using RT-qPCR in our patient set. The association of UBE2R2-AS1 with the clinical data of patients was analyzed. Evaluation of the prognostic value of UBE2R2-AS1 was via Kaplan-Meier and Univariate/Multivariate Cox analyses. The effect of UBE2R2-AS1 on the cancer cell malignant phenotype was investigated. Results. Gastric cancer tissues and cells significantly overexpressed UBE2R2-AS1. UBE2R2-AS1 was significantly more abundant in unfavorable clinical pathology, including advanced TNM stage and lymph node metastasis. High expression of UBE2R2-AS1 predicted a poor prognosis with a hazard ratio (HR) of 3.041 and 2.805 after Univariate and Multivariate Cox analysis, respectively. UBE2R2-AS1 can act as a sponge for miR-302b-5p to promote cell proliferation, migration, and invasion of gastric cancer. Conclusion. The expression of UBE2R2-AS1 allowed the prognostic stratification of gastric cancer patients. UBE2R2-AS1 may accelerate the progression of gastric cancer via miR-302b-5

Conditional Cube Attack on Reduced-Round Keccak Sponge Function

The security analysis of Keccak, the winner of SHA-3, has attracted considerable interest. Recently, some attention has been paid to the analysis of keyed modes of Keccak sponge function. As a notable example, the most efficient key recovery attacks on Keccak-MAC and Keyak were reported at EUROCRYPT\u2715 where cube attacks and cubeattack- like cryptanalysis have been applied. In this paper, we develop a new type of cube distinguisher, the conditional cube tester, for Keccak sponge function. By imposing some bit conditions for certain cube variables, we are able to construct cube testers with smaller dimensions. Our conditional cube testers are used to analyse Keccak in keyed modes. For reduced-round Keccak-MAC and Keyak, our attacks greatly improve the best known attacks in key recovery in terms of the number of rounds or the complexity. Moreover, our new model can also be applied to keyless setting to distinguish Keccak sponge function from random permutation.We provide a searching algorithm to produce the most efficient conditional cube tester by modeling it as an MILP (mixed integer linear programming) problem. As a result, we improve the previous distinguishing attacks on Keccak sponge function significantly. Most of our attacks have been implemented and verified by desktop computers. Finally we remark that our attacks on the the reduced-round Keccak will not threat the security margin of Keccak sponge function

STP Models of Optimal Differential and Linear Trail for S-box Based Ciphers

Automatic tools have played an important role in designing new cryptographic primitives and evaluating the security of ciphers. Simple Theorem Prover constraint solver (STP) has been used to search for differential/linear trails of ciphers. This paper proposes general STP-based models searching for differential and linear trails with the optimal probability and correlation for S-box based ciphers. In order to get trails with the best probability or correlation for ciphers with arbitrary S-box, we give an efficient algorithm to describe probability or correlation of S-Box. Based on the algorithm we present a search model for optimal differential and linear trails, which is efficient for ciphers with S-Boxes whose DDTs/LATs contain entities not equal to the power of two. Meanwhile, the STP-based model for single-key impossible differentials considering key schedule is proposed, which traces the propagation of values from plaintext to ciphertext instead of propagations of differences. And we found that there is no 5-round AES-128 single-key truncated impossible differential considering key schedule, where input and output differences have only one active byte respectively. Finally, our proposed models are utilized to search for trails of bit-wise ciphers GIFT-128, DES, DESL and ICEBERG and word-wise ciphers ARIA, SM4 and SKINNY-128. As a result, improved results are presented in terms of the number of rounds or probabilities/correlations

Role of Demyelination Efficiency within Acellular Nerve Scaffolds during Nerve Regeneration across Peripheral Defects

Hudson’s optimized chemical processing method is the most commonly used chemical method to prepare acellular nerve scaffolds for the reconstruction of large peripheral nerve defects. However, residual myelin attached to the basal laminar tube has been observed in acellular nerve scaffolds prepared using Hudson’s method. Here, we describe a novel method of producing acellular nerve scaffolds that eliminates residual myelin more effectively than Hudson’s method through the use of various detergent combinations of sulfobetaine-10, sulfobetaine-16, Triton X-200, sodium deoxycholate, and peracetic acid. In addition, the efficacy of this new scaffold in repairing a 1.5 cm defect in the sciatic nerve of rats was examined. The modified method produced a higher degree of demyelination than Hudson’s method, resulting in a minor host immune response in vivo and providing an improved environment for nerve regeneration and, consequently, better functional recovery. A morphological study showed that the number of regenerated axons in the modified group and Hudson group did not differ. However, the autograft and modified groups were more similar in myelin sheath regeneration than the autograft and Hudson groups. These results suggest that the modified method for producing a demyelinated acellular scaffold may aid functional recovery in general after nerve defects

Determination of Aroma Composition of Santalum album linn by Solid-phase Microextraction-Gas Chromatography-Mass Spectrometry

[Objectives] This study aimed to determine the volatile components in Santalum album linn and gradually clarify the aroma composition of S. album linn. [Methods] Solid-phase microextraction method was used to obtain the volatile components of S. album linn. The aroma components were analyzed by gas chromatography-mass spectrometry and their relative contents were calculated using the area normalization method. [Results] In a dry state at room temperature, 39 chemical components were identified from S. album linn, mainly olefins (91.15%), alkanes (3.00%), alcohols (2.56%), esters (2.19%), ketones (0.55%), aldehydes (0.41%) and heterocyclics (0.14%). [Conclusions] This method has the advantages of low sample consumption, easy operation, rapid identification of aroma components and high sensitivity, and can effectively separate and determine volatile components in S. album linn, realizing the rapid identification of different S. album linn varieties and providing technical support for further research on Chinese medicinal materials

Interaction between XRCC2 gene polymorphism and abdominal obesity on risk of endometrial carcinoma

AbstractAims The aim of this study was to investigate the impact of three single nucleotide polymorphisms (SNPs) within X-Ray Repair Cross Complementary Group 2 (XRCC2) gene and additional gene- abdominal obesity (AO) interaction with endometrial carcinoma (EC) risk.Methods Hardy–Weinberg equilibrium was tested for all participants by using SNPstats (online software: http://bioinfo.iconcologia.net/SNPstats). The best SNP–SNP and gene–AO interaction combination among three SNPs within XRCC2 gene and AO was screened using generalized multifactor dimensionality reduction (GMDR).Results We employed the logistic regression analysis showed that rs718282-T allele is associated with increased EC risk, adjusted ORs (95%CI) were 1.67 (1.23–2.04). However, we did not find statistical association between rs3218536, and rs3218384 and EC susceptibility. GMDR analysis was used for SNP-SNP- and gene-abdominal obesity analysis. The cross-validation consistency and the testing accuracy for the interaction were calculated. The two-locus model between rs718282 and AO had a testing accuracy of 60.11%, which was significant at the p < .001 level, and this two- locus model was considered as the best model. It provided statistical evidence for rs718282 gene–AO interaction effects. The results indicated that AO influenced the EC risk depending on the rs718282 genotypes. Compared with non- AO subjects with rs718282–CC genotype, AO subjects with rs718282-CT or TT genotype had the highest EC risk, OR (95%CI) was 2.83 (1.67 − 4.02), after covariates adjustment.Conclusions Both the rs718282- T allele, and its interaction with AO were associated with increased EC risk