Multiple Code Sequences Research Articles

Research on Fault Detection by Flow Sequence for Industrial Internet of Things in Sewage Treatment Plant Case.

Classifying the flow subsequences of sensor networks is an effective way for fault detection in the Industrial Internet of Things (IIoT). Traditional fault detection algorithms identify exceptions by a single abnormal dataset and do not pay attention to the factors such as electromagnetic interference, network delay, sensor sample delay, and so on. This paper focuses on fault detection by continuous abnormal points. We proposed a fault detection algorithm within the module of sequence state generated by unsupervised learning (SSGBUL) and the module of integrated encoding sequence classification (IESC). Firstly, we built a network module based on unsupervised learning to encode the flow sequence of the different network cards in the IIoT gateway, and then combined the multiple code sequences into one integrated sequence. Next, we classified the integrated sequence by comparing the integrated sequence with the encoding fault type. The results obtained from the three IIoT datasets of a sewage treatment plant show that the accuracy of the SSGBUL-IESC algorithm exceeds 90% with subsequence length 10, which is significantly higher than the accuracies of the dynamic time warping (DTW) algorithm and the time series forest (TSF) algorithm. The proposed algorithm reaches the classification requirements for fault detection for the IIoT.

Vanadium dioxide based terahertz dual-frequency multi-function coding metasurface

Terahertz (THz) wave has the advantages of low photon energy, high resolution, large communication bandwidth, etc. It has broad application prospects in security detection, high-resolution imaging, high-speed communication, and other fields. In recent years, as a new way to control THz wave, THz metasurface functional devices have attracted extensive attention of researchers. In this work, vanadium dioxide (VO<sub>2</sub>), a phase change material, is introduced into the coding metasurface. By regulating a circularly polarized wave and the orthogonal linearly polarized waves independently, a multi-function coding metasurface that can work at dual frequency points is obtained. It is composed of three layers. The top layer is a metal-VO<sub>2</sub> composite structure. The middle is a polyimide dielectric layer. The bottom is a metal ground. Under certain conditions, the double split ring resonator (DSRR) and the cross structure in the top layer are relatively independent. Designing the coding sequences for them enable the coding metasurface to have multiple functions. The electromagnetic simulation software CST is used to establish model and conduct simulation, and the obtained results are as follows. When the VO<sub>2</sub> is in an insulating state and a circularly polarized wave at 0.34 THz is incident vertically, the characteristics of coding metasurface elements are mainly affected by the DSRR. The DSRR is rotated to meet the requirements of 3-bit Pancharatnam-Berry phase coding. The coding sequence is designed to generate vortex beams with the topological charge <i>l</i> = ±1 at a specific angle. The VO<sub>2</sub> state is changed into a metallic state, and the DSRR can be equivalent to a metal ring. When the orthogonal linearly polarized wave at 0.74 THz is incident vertically, the characteristics of coding metasurface elements are mainly affected by the cross structure. Because of its anisotropy, four different 2-bit coding metasurface elements can be obtained respectively by changing the length of the horizontal arm and the vertical arm. The design of appropriate coding sequences can reduce the radar cross section of the <i>x</i>-polarized wave and the beam splitting of the <i>y</i>-polarized wave, and the results have broadband characteristics. Multiple coding sequences can be designed by special characteristics of the coding metasurface, then various expected functions can be realized on the same metasurface. It solves the problem of single function of ordinary metasurface devices to a certain extent, and paves a novel way to the development of THz multi-function systems.

Identification of novel, cryptic Clostridioides species isolates from environmental samples collected from diverse geographical locations.

Clostridioides difficile is a pathogen often associated with hospital-acquired infection or antimicrobial-induced disease; however, increasing evidence indicates infections can result from community or environmental sources. Most genomic sequencing of C. difficile has focused on clinical strains, although evidence is growing that C. difficile spores are widespread in soil and water in the environment. In this study, we sequenced 38 genomes collected from soil and water isolates in Flagstaff (AZ, USA) and Slovenia in an effort targeted towards environmental surveillance of C. difficile . At the average nucleotide identity (ANI) level, the genomes were divergent to C. difficile at a threshold consistent with different species. A phylogenetic analysis of these divergent genomes together with Clostridioides genomes available in public repositories confirmed the presence of three previously described, cryptic Clostridioide s species and added two additional clades. One of the cryptic species (C-III) was almost entirely composed of Arizona and Slovenia genomes, and contained distinct sub-groups from each region (evidenced by SNP and gene-content differences). A comparative genomics analysis identified multiple unique coding sequences per clade, which can serve as markers for subsequent environmental surveys of these cryptic species. Homologues to the C. difficile toxin genes, tcdA and tcdB, were found in cryptic species genomes, although they were not part of the typical pathogenicity locus observed in C. difficile , and in silico PCR suggested that some would not amplify with widely used PCR diagnostic tests. We also identified gene homologues in the binary toxin cluster, including some present on phage and, for what is believed to be the first time, on a plasmid. All isolates were obtained from environmental samples, so the function and disease potential of these toxin homologues is currently unknown. Enzymatic profiles of a subset of cryptic isolates (n=5) demonstrated differences, suggesting that these isolates contain substantial metabolic diversity. Antimicrobial resistance (AMR) was observed across a subset of isolates (n=4), suggesting that AMR mechanisms are intrinsic to the genus, perhaps originating from a shared environmental origin. This study greatly expands our understanding of the genomic diversity of Clostridioides . These results have implications for C. difficile One Health research, for more sensitive C. difficile diagnostics, as well as for understanding the evolutionary history of C. difficile and the development of pathogenesis.

Characterizing seamless ligation cloning extract for synthetic biological applications

Synthetic biology aims at designing and engineering organisms. The engineering process typically requires the establishment of suitable DNA constructs generated through fusion of multiple protein coding and regulatory sequences. Conventional cloning techniques, including those involving restriction enzymes and ligases, are often of limited scope, in particular when many DNA fragments must be joined or scar-free fusions are mandatory. Overlap-based-cloning methods have the potential to overcome such limitations. One such method uses seamless ligation cloning extract (SLiCE) prepared from Escherichia coli cells for straightforward and efficient in vitro fusion of DNA fragments. Here, we systematically characterized extracts prepared from the unmodified E. coli strain DH10B for SLiCE-mediated cloning and determined DNA sequence-associated parameters that affect cloning efficiency. Our data revealed the virtual absence of length restrictions for vector backbone (up to 13.5 kbp) and insert (90 bp to 1.6 kbp). Furthermore, differences in GC content in homology regions are easily tolerated and the deletion of unwanted vector sequences concomitant with targeted fragment insertion is straightforward. Thus, SLiCE represents a highly versatile DNA fusion method suitable for cloning projects in virtually all molecular and synthetic biology projects.

Bit-Error Probability of Asynchronous Multicode DS-CDMA Systems in Rayleigh Fading

A precise bit-error probability analysis method for multicode DS-CDMA systems in Rayleigh fading is derived. The proposed method applies to a multicode DS-CDMA system with an arbitrary number of multiple code sequences and any selection of multiple code sequences. The method gives accurate results for Rayleigh fading while requiring only a single numerical integration of an integrand involving the well-known Q-function. The solution discriminates the effect of the selection of different multiple code sequences on the bit-error probability, whereas Gaussian approximations do not. Numerical examples show that the differences between exact and approximate methods for a multicode DS-CDMA system operating over Rayleigh fading channels may be more significant than for a single code system in Rayleigh fading channels or for a multicode system in AWGN channels when the spreading factor is not significantly large compared to the number of multiple code sequences.

Multiple coding sequences for the genome-linked virus protein (VPg) in dicistroviruses

N-terminal Edman sequencing of the genome-linked viral protein (VPg) of Plautia stali intestine virus (PSIV, Dicistroviridae) detected heterologus residues. The VPg sequence determined was found to be triplicated in the nonstructural protein precursor. Multiple VPg-like sequences were also found in 10 of the 12 dicistroviruses with a maximum of six copies in Solenopsis invicta virus-1. We postulate that redundant VPg coding sequences facilitate multiplication of dicistroviruses, because fewer cycle of translation of the nonstructural protein precursor produces larger amounts of VPg proteins in parallel with the increased production of capsid proteins by the intergenic internal ribosome entry site mediated translation.

Precise analysis of bit-error probability for asynchronous multicode DS-CDMA systems

A precise bit-error probability (BEP) analysis method is derived for a multicode direct-sequence code-division multiple-access (DS-CDMA) system in an additive white Gaussian noise channel. The method is applicable to a multicode DS-CDMA system with an arbitrary number of multiple code sequences, and any selection of multiple code sequences. The precise method gives results that discriminate the effect of the selection of different multiple code sequences on the BEP, whereas Gaussian approximations (GAs) do not. Thus, the new method can be used to select the best multicode set for a given system, a task that cannot be achieved using GAs. A two-step analytical procedure enables deriving an explicit, compact form for the CF of the receiver decision statistic in a DS-CDMA system with an arbitrary number of multiple code sequences, and for any selection of multiple code sequences.

Code Sequences for Spread Spectrum Multiple Access Applications

Spread Spectrum Multiple Access Code Sequences find use in a number of systems where spread spectrum technologies are employed for digital communications. Broadly, these “spectrum spreading” code sequences can be classified into two categories, viz, direct sequence codes and frequency hoping codes. This paper first presents a brief review of the important classes of existing code sequences and then goes on to present some interesting new results obtained by the authors recently. These results enable us to construct several useful classes of sequence sets, which possess both optimal (or near optimal) correlation properties as well as a large linear span. The large linear span is desirable in many applications where communication security is of interest.

The selection, expression, and organization of a set of head-specific genes in Drosophila

Comparative screening of a library of cloned Drosophila DNA with polyadenylated mRNA from Drosophila adult head and adult body identified 20 cloned sequences expressed more abundantly in the tissues of the head than in other tissues. Quantitation using a “dot blot” hybridization assay demonstrated that the DNA sequences are expressed on adult head polysomes from 3 to 177 times more abundantly than on body polysomes, and their transcripts represent from 0.05 to 0.66% of the polyadenylated mRNA mass of the head. The steady-state nuclear RNA concentrations of four species were determined to be from 13 to 48 times greater in head nuclei than in body nuclei, an indication that their expression is controlled at least in part at the transcriptional level. The chromosomal locations of all 20 head-specific clones were identified by in situ mapping, and no distinct clustering was observed. However, four of the clones were shown by Southern and Northern blot analysis to contain multiple RNA coding sequences. The genes in these tightly clustered sets were observed to be expressed simultaneously in some cases and differently in others.