Digital Twin Modeling of a Five-Axis Linkage Crossbeam Mobile Gantry Milling Machine

In the innovative design stage of machine tool (MT), in order to understand the motion status of the MT under different conditions, shorten the development cycle, and improve machining accuracy, this paper proposes a digital twin modeling method for large crossbeam mobile gantry milling machines. By combining digital twin technology, the selection of MT motion components and the design of various motion mechanisms were completed, as well as the machining scheme design of the MT bed. Modeling and simulation were conducted to complete the workpiece machining function, By using digital twin technology to virtually simulate CNC MT and verify their properties in physical prototypes, new ideas are provided for the application of digital twin technology in the design process of CNC MT.</p

Biochemical characterization of the major DNA-binding protein of murine cytomegalovirus

Murine cytomegalovirus (MCMV) has been extensively used as a model for Human cytomegalovirus (HCMV) infection due to its striking biological similarities to HCMV. The MCMV major DNA-binding protein (MDBP) is a non-structural protein produced during early times of viral infection. The protein encoded by the M57 open reading frame (ORF) of the viral genome has previously been shown to share significant amino acid sequence similarity to both HCMV single-stranded DNA-binding protein (ssDBP) and herpes simplex virus type 1 (HSV-1) ICP8. HSV-1 ICP8 is one of seven essential proteins required for viral DNA replication. In this study, I characterized the biochemical properties of the MCMV MDBP, especially the single-stranded DNA-binding domain and nuclear localization signals (NLSs) of the protein. To do this, the M57 ORF encoding MCMV MDBP was first cloned into an expression vector. The histidine-tagged MCMV MDBP fusion protein was produced and used to develop a panel of monoclonal antibodies (MAbs) which recognized epitopes located within the N- and C-termini of the MDBP. These MAbs were used to monitor the expression of wild type (wt) and mutant MDBPs during infection and transfection experiments, and facilitated the characterization of the biochemical properties of MCMV MDBP. Single-stranded DNA-cellulose column chromatography was carried out to assess the ssDNA-binding property of the wild type (wt) and mutant MDBPs; synthesized in an ' in vitro' coupled transcription-translation reaction. Nuclear localization signal regions were identified by transiently expressing the mutant MDBP gene in COS-1 cells and observing the subcellular localization of the expressed protein with indirect immunofluorescence. Gel filtration chromatography was performed to define the native molecular weight of the MDBP extracted from MCMV-infected cells. The results demonstrated that wt MDBP was eluted from the ssDNA-cellulose column at 250 mM NaCl. Deletion of a region containing a zinc finger-like motif completely abolished ssDNA-binding. However, the ssDNA-binding activity of the protein was found to reside largely in the C-terminal half of the protein. Partial deletion of a putative ssDNA-binding motif significantly affected ssDNA-binding. In indirect immunofluorescence experiments, the MDBP was localized to discrete areas of the nuclei of infected cells. In contrast, a more diffuse nuclear staining pattern was evident during transient expression of the protein in COS-1 cells. Although the C-terminus of the protein contains two clusters of basic residues capable of targeting a heterologous cytoplasmic protein to the nucleus, the N-terminus of the protein, which also contains such residues, appeared to constitute the major determinant for the nuclear localization of MCMV MDBP. Finally, while the protein migrated as a monomer with an apparent molecular weight of 133 K in SDS-PAGE, it was found mainly in high molecular weight complexes of in excess of 200 K in MCMV-infected cells. Collectively, these results indicate that MCMV MDBP is similar in many aspects but not identical to the previously reported HSV-1 counterpart, ICP8. (Abstract shortened by UMI.

Study on Response Characteristics of Styrax tonkinensis to Heavy Metal Stress

[Objectives] To explore the response characteristics of chlorophyll and photosynthesis in Styrax tonkinensis under different concentrations of copper and cadmium stress and analyze the internal mechanism of the effects of copper and cadmium pollution stress on photosynthesis. [Methods] Taking seedlings of S. tonkinensis as the research object, the response characteristics of chlorophyll and photosynthesis of S. tonkinensis were compared under different concentrations of copper and cadmium. [Results] With the increase of copper and cadmium treatment concentrations, the chlorophyll content first rose and then fell. With the increase of cadmium concentration, the net photosynthetic rate of S. tonkinensis plants increased from decrease to increase, and the stomatal conductance, transpiration rate and intercellular CO2 concentration all increased. [Conclusions] Under the stress of different concentrations of cadmium, the photosynthetic characteristics of S. tonkinensis were not obviously inhibited. Copper stress has inhibitory effect on photosynthesis of S. tonkinensis

Slow Light Effect and Tunable Channel in Graphene Grating Plasmonic Waveguide

A graphene plasmon waveguide composed of silicon grating substrate and a silica separator is proposed to generate the slow-light effect. A bias voltage is applied to tune the optical conductivity of graphene. The tunability of the slow-light working channel can be achieved due to the adjustable bias voltage. With an increase in the bias voltage, the working channel exhibited obvious linear blue-shift. The linear correlation coefficient between the working channel and the bias voltage was up to 0.9974. The average value of the normalized delay bandwidth product (NDBP) with different bias voltages was 3.61. In addition, we also studied the tunable group velocity at a specific working channel. Due to the tunability of this miniaturized waveguide structure, it can be used in a variety of applications including optical storage devices, optical buffers and optical switches

Development, Reliability, and Validity of the“Knowledge-Attitude-Practice” Questionnaire of Foreigners on Traditional Chinese Medicine Treatment

Objective. To develop a “knowledge-attitude-practice” questionnaire as an evaluating tool of foreigners’ cognition on TCM treatment, so as to promote the internationalization of TCM. Methods. The questionnaire was based on the “knowledge-attitude-practice” model and adjusted by expert consultation using the Delphi method. After conducting a survey among foreigners, Cronbach’s α and exploratory factor analysis were used to test the internal consistency reliability and structural validity of the questionnaire, respectively. Results. A total of 10 experts participated in two rounds of expert consultation. The recovery rates of two rounds of expert consultation form were 100.0%. The coefficient authority in two rounds of expert consultation was 0.87 and 0.88, respectively. The concentration of expert opinions in the knowledge, attitude, and practice dimensions was 3.80 to 4.70 points, 3.70 to 4.50 points, and 3.60 to 4.40 points, respectively, in the first round and 4.30 to 4.80 points, 4.10 to 4.60 points, and 4.00 to 4.50 points, respectively, in the second round. The coefficient of variation in the knowledge, attitude, and practice dimensions was 0.10–0.32, 0.16–0.29, and 0.19–0.35, respectively, in the first round and 0.09–0.19, 0.15–0.25, and 0.16–0.31, respectively, in the second round. The W value and significance test x2 in the first round were 0.657 and 218.620 while those in the second round were 0.671 and 181.181P<0.001. 8 items were deleted and 1 item was added, and other reserved items were modified according to the statistical analysis results of evaluation items and expert suggestions after the first round and there were no changes after the second round. The revised questionnaire includes three dimensions of knowledge, attitude, and practice, with a total of 30 items. After translating the questionnaire into English, it was conducted in 176 foreigners. Cronbach’s α coefficient of the total questionnaire, knowledge dimension, attitude dimension, and practice dimension was 0.908, 0.781, 0.823, and 0.918, respectively. Exploratory factor analysis extracted 3 factors with a cumulative contribution of 54.090%. After testing reliability and validity, 1 item was deleted, leaving 29 items. Conclusions. After two rounds of expert consultation based on the Delphi method, the results of expert authority, expert coordination, and expert opinions’ concentration were promising, and the expert consultation results were reliable. The “knowledge-attitude-practice” questionnaire of foreigners on TCM treatment in English had good reliability and validity and can evaluate foreigners’ cognition on TCM treatment

The complete chloroplast genome of Uvaria macrophylla Roxb. (Annonaceae)

Uvaria macrophylla (Annonaceae) is an erect shrub with multiple medicinal properties. In this study, we report the complete chloroplast genome of U. macrophylla, assembled from whole-genome high-throughput sequencing reads, as a resource for future studies on the phylogeny and evolution of Annonaceae. The chloroplast genome was 192,782 bp in length, with a large single-copy (LSC) region of 83,581 bp, a small single-copy (SSC) region of 3,741 bp, separated by two inverted repeat (IR) regions of 52,730 bp each. It was predicted to contain 151 genes, with an overall GC content of 38.7%. Phylogenetic analysis of 105 protein-coding sequences of 13 plant plastomes showed that U. macrophylla is closest to Annona cherimola

An AIE Metal Iridium Complex: Photophysical Properties and Singlet Oxygen Generation Capacity

Photodynamic therapy (PDT) has garnered significant attention in the fields of cancer treatment and drug-resistant bacteria eradication due to its non-invasive nature and spatiotemporal controllability. Iridium complexes have captivated researchers owing to their tunable structure, exceptional optical properties, and substantial Stokes displacement. However, most of these complexes suffer from aggregation-induced quenching, leading to diminished luminous efficiency. In contrast to conventional photosensitizers, photosensitizers exhibiting aggregation-induced luminescence (AIE) properties retain the ability to generate a large number of reactive oxygen species when aggregated. To overcome these limitations, we designed and synthesized a novel iridium complex named Ir-TPA in this study. It incorporates quinoline triphenylamine cyclomethylated ligands that confer AIE characteristics for Ir-TPA. We systematically investigated the photophysical properties, AIE behavior, spectral features, and reactive oxygen generation capacity of Ir-TPA. The results demonstrate that Ir-TPA exhibits excellent optical properties with pronounced AIE phenomenon and robust capability for producing singlet oxygen species. This work not only introduces a new class of metal iridium complex photosensitizer with AIE attributes but also holds promise for achieving remarkable photodynamic therapeutic effects in future cellular experiments and biological studies