311 research outputs found
Phylogenetic and evolutionary analysis of the septin protein family in metazoan
AbstractSeptins, a conserved family of cytoskeletal GTP-binding proteins, were presented in diverse eukaryotes. Here, a comprehensive phylogenetic and evolutionary analysis for septin proteins in metazoan was carried out. First, we demonstrated that all septin proteins in metazoan could be clustered into four subgroups, and the representative homologue of every subgroup was presented in the non-vertebrate chordate Ciona intestinalis, indicating that the emergence of the four septin subgroups should have occurred prior to divergence of vertebrates and invertebrates, and the expansion of the septin gene number in vertebrates was mainly by the duplication of pre-existing genes rather than by the appearance of new septin subgroup. Second, the direct orthologues of most human septins existed in zebrafish, which suggested that human septin gene repertoire was mainly formed by as far as before the split between fishes and land vertebrates. Third, we found that the evolutionary rate within septin family in mammalian lineage varies significantly, human SEPT1, SEPT 10, SEPT 12, and SEPT 14 displayed a relative elevated evolutionary rate compared with other septin members. Our data will provide new insights for the further function study of this protein family
An Improved VFF Approach for Robot Path Planning in Unknown and Dynamic Environments
Robot path planning in unknown and dynamic environments is one of the hot topics in the field of robot control. The virtual force field (VFF) is an efficient path planning method for robot. However, there are some shortcomings of the traditional VFF based methods, such as the local minimum problem and the higher computational complexity, in dealing with the dynamic obstacle avoidance. In this paper, an improved VFF approach is proposed for the real-time robot path planning, where the environment is unknown and changing. An area ratio parameter is introduced into the proposed VFF based approach, where the size of the robot and obstacles are considered. Furthermore, a fuzzy control module is added, to deal with the problem of obstacle avoidance in dynamic environments, by adjusting the rotation angle of the robot. Finally, some simulation experiments are carried out to validate and demonstrate the efficiency of the proposed approach
Demystifying Compiler Unstable Feature Usage and Impacts in the Rust Ecosystem
Rust programming language is gaining popularity rapidly in building reliable
and secure systems due to its security guarantees and outstanding performance.
To provide extra functionalities, the Rust compiler introduces Rust unstable
features (RUF) to extend compiler functionality, syntax, and standard library
support. However, these features are unstable and may get removed, introducing
compilation failures to dependent packages. Even worse, their impacts propagate
through transitive dependencies, causing large-scale failures in the whole
ecosystem. Although RUF is widely used in Rust, previous research has primarily
concentrated on Rust code safety, with the usage and impacts of RUF from the
Rust compiler remaining unexplored. Therefore, we aim to bridge this gap by
systematically analyzing the RUF usage and impacts in the Rust ecosystem. We
propose novel techniques for extracting RUF precisely, and to assess its impact
on the entire ecosystem quantitatively, we accurately resolve package
dependencies. We have analyzed the whole Rust ecosystem with 590K package
versions and 140M transitive dependencies. Our study shows that the Rust
ecosystem uses 1000 different RUF, and at most 44% of package versions are
affected by RUF, causing compiling failures for at most 12%. To mitigate wide
RUF impacts, we further design and implement a RUF-compilation-failure recovery
tool that can recover up to 90% of the failure. We believe our techniques,
findings, and tools can help to stabilize the Rust compiler, ultimately
enhancing the security and reliability of the Rust ecosystem.Comment: Published in ICSE'2024 Conference:
https://conf.researchr.org/details/icse-2024/icse-2024-research-track/6/Demystifying-Compiler-Unstable-Feature-Usage-and-Impacts-in-the-Rust-Ecosystem.
Project webiste: https://sites.google.com/view/ruf-study/home. Released
Source Code Zonodo: https://zenodo.org/records/828937
PA-Boot: A Formally Verified Authentication Protocol for Multiprocessor Secure Boot
Hardware supply-chain attacks are raising significant security threats to the
boot process of multiprocessor systems. This paper identifies a new, prevalent
hardware supply-chain attack surface that can bypass multiprocessor secure boot
due to the absence of processor-authentication mechanisms. To defend against
such attacks, we present PA-Boot, the first formally verified
processor-authentication protocol for secure boot in multiprocessor systems.
PA-Boot is proved functionally correct and is guaranteed to detect multiple
adversarial behaviors, e.g., processor replacements, man-in-the-middle attacks,
and tampering with certificates. The fine-grained formalization of PA-Boot and
its fully mechanized security proofs are carried out in the Isabelle/HOL
theorem prover with 306 lemmas/theorems and ~7,100 LoC. Experiments on a
proof-of-concept implementation indicate that PA-Boot can effectively identify
boot-process attacks with a considerably minor overhead and thereby improve the
security of multiprocessor systems.Comment: Manuscript submitted to IEEE Trans. Dependable Secure Compu
Room-temperature multiferroic hexagonal LuFeO films
The crystal and magnetic structures of single-crystalline hexagonal LuFeO
films have been studied using x-ray, electron and neutron diffraction methods.
The polar structure of these films are found to persist up to 1050 K; and the
switchability of the polar behavior is observed at room temperature, indicating
ferroelectricity. An antiferromagnetic order was shown to occur below 440 K,
followed by a spin reorientation resulting in a weak ferromagnetic order below
130 K. This observation of coexisting multiple ferroic orders demonstrates that
hexagonal LuFeO films are room-temperature multiferroics
Prevalence and genotype distribution of HPV infection among women in Xiamen, China
ObjectiveThis study aimed to evaluate the prevalence of HPV and genotype distribution among female populations in Xiamen, Fujian Province, China, which can be conducive for local governments to formulate cervical cancer screening and HPV vaccine strategies.MethodsCervical swabs were collected from 47,926 participants aged 16–92 years at the Women and Children’s Hospital, Xiamen University, from November 2019 to June 2020. HPV DNA was extracted and detected using conventional PCR, followed by HPV subtype-specific hybridisation. HPV infection rates based on different groups were compared using the χ2 test. HPV prevalence and the corresponding 95% confidence intervals (95% CI) were calculated using SPSS 19.0.ResultsThe overall HPV prevalence among the 47,926 cervical swabs that were analysed was 15.13%, of which single, double, and multiple infections accounted for 76.83, 16.70 and 6.47%, respectively. The age-specific prevalence of HPV infection presented a “U” curve with a HPV prevalence peak observed in women aged <20 years. The gynaecology clinic group had significantly higher HPV positive rates than the health examination group (p < 0.001). The five most common HR-HPV subtypes in Xiamen were HPV52, 58, 16, 51, and 39 (2.69, 1.63, 1.23, 1.05, and 0.98%, respectively). The five most common LR-HPV subtypes were HPV54, 61, 81, 70, 34, and 84 (0.92, 0.86, 0.71, 0.45 and 0.35%, respectively).ConclusionOur findings demonstrate that the 9-valent HPV vaccine is recommended for regular immunisation in Xiamen. It is necessary for elderly women to participate in HPV screening to decrease the morbidity and mortality of cervical cancer
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