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1.
Biochem Biophys Res Commun ; 695: 149451, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38176173

RESUMEN

BACKGROUND/OBJECTIVE: DT-13, the principal active component of Mysidium shortscapes from the Liliaceae family, has garnered substantial interest in cancer therapy owing to its potential anticancer properties. This study investigated the effects of DT-13 on the proliferation and apoptosis of human pancreatic cancer cell lines and aimed to elucidate the underlying mechanisms. METHODS: PANC1 and CFPAC1 cells were exposed to DT-13 and their proliferation was assessed using RTCA and clone formation assays. Apoptotic protein expression was analyzed by western blotting, and apoptotic cells were identified by flow cytometry. RNA was extracted from DT-13 treated and untreated PANC1 cells for RNA sequencing. Differentially expressed genes were identified and subjected to GO bioprocess, KEGG pathway analysis, and western blotting. Finally, to evaluate tumor growth, CFPAC1 cells were subcutaneously injected into BALB/c nude mice. RESULTS: DT-13 inhibited proliferation and induced apoptosis of PANC1 and CFPAC1 cells by activating the AMPK/mTOR pathway and suppressing p70 S6K. Moreover, DT-13 hindered the growth of CFPAC1 xenograft tumors in nude mice. CONCLUSIONS: DT-13 effectively inhibited the growth of human pancreatic cancer cells.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Neoplasias Pancreáticas , Saponinas , Animales , Humanos , Ratones , Proteínas Quinasas Activadas por AMP/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/metabolismo , Serina-Treonina Quinasas TOR/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Saponinas/farmacología , Saponinas/uso terapéutico
2.
BMC Plant Biol ; 24(1): 361, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38702620

RESUMEN

BACKGROUND: Solanum muricatum is an emerging horticultural fruit crop with rich nutritional and antioxidant properties. Although the chromosome-scale genome of this species has been sequenced, its mitochondrial genome sequence has not been reported to date. RESULTS: PacBio HiFi sequencing was used to assemble the circular mitogenome of S. muricatum, which was 433,466 bp in length. In total, 38 protein-coding, 19 tRNA, and 3 rRNA genes were annotated. The reticulate mitochondrial conformations with multiple junctions were verified by polymerase chain reaction, and codon usage, sequence repeats, and gene migration from chloroplast to mitochondrial genome were determined. A collinearity analysis of eight Solanum mitogenomes revealed high structural variability. Overall, 585 RNA editing sites in protein coding genes were identified based on RNA-seq data. Among them, mttB was the most frequently edited (52 times), followed by ccmB (46 times). A phylogenetic analysis based on the S. muricatum mitogenome and those of 39 other taxa (including 25 Solanaceae species) revealed the evolutionary and taxonomic status of S. muricatum. CONCLUSIONS: We provide the first report of the assembled and annotated S. muricatum mitogenome. This information will help to lay the groundwork for future research on the evolutionary biology of Solanaceae species. Furthermore, the results will assist the development of molecular breeding strategies for S. muricatum based on the most beneficial agronomic traits of this species.


Asunto(s)
Genoma Mitocondrial , Filogenia , Edición de ARN , Solanum , Solanum/genética , Genoma de Planta
3.
Small ; : e2401596, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38889398

RESUMEN

All inorganic lead halide perovskites exhibit fascinating optical and optoelectronic characteristics for on-chip lasing, but the lack of precise control of wafer-scale fabrication for perovskite microstructure arrays restricts their potential applications in on-chip-integrated devices. In this work, a microstructure-template assisted crystallization method is demonstrated via a designed chemical vapor deposition process, achieving the controllable fabrication of homogeneous perovskite micro-hemispheroid (PeMH) arrays spanning the entire surface area of a 4-inch wafer. Benefiting from the low-loss whispering gallery resonance and plasmon-enhanced light-matter interactions in well-confined hybrid cavities, this CsPbX3/Ag (X = Cl, Br) plasmonic microlasers exhibit quite low thresholds below 10 µJ cm-2. Interestingly, these thresholds can be efficiently modulated through the manipulation of plasmonic resonance and electromagnetic field mode in PeMHs owning various diameters. This strategy not only provides a valuable methodology for the large-scale fabrication of perovskite microstructures but also endorses the potential of all-inorganic perovskite nanostructures as promising candidates for on-chip-integrated light sources.

4.
Small ; : e2401939, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38924354

RESUMEN

3D carbon-based porous sponges are recognized for significant potential in oil absorption and electromagnetic interference (EMI). However, their widespread application is hindered by a common compromise between high performance and affordability of mass production. Herein, a novel approach is introduced that involves laser-assisted micro-zone heating melt-blown spinning (LMHMS) to address this challenge by creating pitch-based submicron carbon fibers (PSCFs) sponge with 3D interconnected structures. These structures bestow the resulting sponge exceptional characteristics including low density (≈20 mg cm-3), high porosity (≈99%), remarkable compressibility (80% maximum strain), and superior conductivity (≈628 S m-1). The resultant PSCF sponges realize an oil/organic solvent sorption capacity over 56 g/g and possess remarkable regenerated ability. In addition to their effectiveness in cleaning up oil/organic solvent spills, they also demonstrated strong electromagnetic shielding capabilities, with a total shielding effectiveness (SE) exceeding 60 dB across the X-band GHz range. In virtue of extreme lightweight of ≈20 mg cm-3, the specific SE of the PSCF sponge reaches as high as ≈1466 dB cm3 g-1, surpassing the performance of numerous carbon-based porous structures. Thus, the unique blend of properties renders these sponges promising for transforming strategies in addressing oil/organic solvent contaminations and providing effective protection against EMI.

5.
J Transl Med ; 22(1): 546, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849907

RESUMEN

BACKGROUND: The pathogenesis of thyroid-associated orbitopathy (TAO) remains incompletely understand. The interaction between immunocytes and orbital fibroblasts (OFs) play a critical role in orbital inflammatory and fibrosis. Accumulating reports indicate that a significant portion of plasma exosomes (Pla-Exos) are derived from immune cells; however, their impact upon OFs function is unclear. METHODS: OFs were primary cultured from inactive TAO patients. Exosomes isolated from plasma samples of patients with active TAO and healthy controls (HCs) were utilized for functional and RNA cargo analysis. Functional analysis in thymocyte differentiation antigen-1+ (Thy-1+) OFs measured expression of inflammatory and fibrotic markers (mRNAs and proteins) and cell activity in response to Pla-Exos. RNA cargo analysis was performed by RNA sequencing and RT-qPCR. Thy-1+ OFs were transfected with miR-144-3p mimics/inhibitors to evaluate its regulation of inflammation, fibrosis, and proliferation. RESULTS: Pla-Exos derived from active TAO patients (Pla-ExosTAO-A) induced stronger production of inflammatory cytokines and hyaluronic acid (HA) in Thy-1+ OFs while inhibiting their proliferation. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and single sample gene set enrichment analysis (ssGSEA) suggested that the difference in mRNA expression levels between Pla-ExosTAO-A and Pla-ExosHC was closely related to immune cells. Differential expression analysis revealed that 62 upregulated and 45 downregulated miRNAs in Pla-ExosTAO-A, with the elevation of miR-144-3p in both Pla-Exos and PBMCs in active TAO group. KEGG analysis revealed that the target genes of differentially expressed miRNA and miR-144-3p enriched in immune-related signaling pathways. Overexpression of the miR-144-3p mimic significantly upregulated the secretion of inflammatory cytokines and HA in Thy-1+ OFs while inhibiting their proliferation. CONCLUSION: Pla-Exos derived from patients with active TAO were immune-active, which may be a long-term stimulus casual for inflammatory and fibrotic progression of TAO. Our finding suggests that Pla-Exos could be used as biomarkers or treatment targets in TAO patients.


Asunto(s)
Exosomas , Fibroblastos , Fibrosis , Oftalmopatía de Graves , Inflamación , MicroARNs , Órbita , Humanos , Exosomas/metabolismo , Oftalmopatía de Graves/patología , Oftalmopatía de Graves/sangre , Oftalmopatía de Graves/genética , MicroARNs/genética , MicroARNs/metabolismo , MicroARNs/sangre , Fibroblastos/metabolismo , Fibroblastos/patología , Órbita/patología , Inflamación/patología , Femenino , Masculino , Proliferación Celular , Persona de Mediana Edad , Adulto , Ácido Hialurónico/sangre , Ácido Hialurónico/metabolismo , Citocinas/metabolismo , Antígenos Thy-1/metabolismo
6.
Opt Express ; 32(3): 4201-4214, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297626

RESUMEN

Multimode fibers (MMF) show tremendous potential in transmitting high-capacity spatial information. However, the quality of multimode transmission is quite sensitive to inherent scattering characteristics of MMF and almost inevitable external perturbations. Previous research has shown that deep learning may break through this limitation, while deep neural networks are intricately designed with huge computational complexity. In this study, we propose a novel feature decoupled knowledge distillation (KD) framework for lightweight image transmission through MMF. In this framework, the frequency-principle-inspired feature decoupled module significantly improves image transmission quality and the lightweight student model can reach the performance of the sophisticated teacher model through KD. This work represents the first effort, to the best of our knowledge, that successfully applies a KD-based framework for image transmission through scattering media. Experimental results demonstrate that even with up to 93.4% reduction in model computational complexity, we can still achieve averaged Structure Similarity Index Measure (SSIM) of 0.76, 0.85, and 0.90 in Fashion-MNIST, EMNIST, and MNIST images respectively, which are very close to the performance of cumbersome teacher models. This work dramatically reduces the complexity of high-fidelity image transmission through MMF and holds broad prospects for applications in resource-constrained environments and hardware implementations.

7.
Opt Express ; 32(6): 8623-8637, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571117

RESUMEN

In fiber-terahertz integrated communication systems, nonlinear distortion and inter-symbol interference (ISI) will degrade transmission performance. Pre-compensation is an efficient method to handle the channel distortion as it can avoid noise boosting during channel compensation and reduce receiver side signal processing algorithmic complexity at user-end (UE) considering the asymmetric access scenario. In this paper, we propose and experimentally demonstrate a neural-network (NN)-based carrier-less amplitude phase (CAP) modulated signal generation and end-to-end optimization method for a fiber-terahertz integrated communication system. The CAP signal is generated directly from quadrature amplitude modulation symbols and pre-compensated through a transmitter NN, which allows the receiver to demodulate the signal with simple linear digital signal process (DSP). In generating the CAP signal, the NN based transmitter learns a group of filters, which can generate, up-convert, and pre-compensate the signals. Based on the proposed method, a fiber-terahertz integration access system at 220 GHz is demonstrated and a sensitivity gain of 1.2 dB is achieved at a transmission speed of 50 Gbps and the forward error correction (FEC) bit error rate (BER) threshold of 1 × 10-2 compared with the baseline after 10-km fiber transmission and 1-m wireless delivering.

8.
Opt Express ; 32(8): 13095-13110, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859288

RESUMEN

Modulation format recognition (MFR) is a key technology for adaptive optical systems, but it faces significant challenges in underwater visible light communication (UVLC) due to the complex channel environment. Recent advances in deep learning have enabled remarkable achievements in image recognition, owing to the powerful feature extraction of neural networks (NN). However, the high computational complexity of NN limits their practicality in UVLC systems. This paper proposes a communication-informed knowledge distillation (CIKD) method that achieves high-precision and low-latency MFR with an ultra-lightweight student model. The student model consists of only one linear dense layer under a communication-informed auxiliary system and is trained under the guidance of a high-complexity and high-precision teacher model. The MFR task involves eight modulation formats: PAM4, QPSK, 8QAM-CIR, 8QAM-DIA, 16QAM, 16APSK, 32QAM, and 32APSK. Experimental results show that the student model based on CIKD can achieve comparable accuracy to the teacher model. After knowledge transfer, the prediction accuracy of the student model can be increased by up to 87%. Besides, it is worth noting that CIKD's inference accuracy can reach up to 100%. Moreover, the parameters constituting the student model in CIKD correspond to merely 18% of the parameters found in the teacher model, which facilitates the hardware deployment and online data processing of MFR algorithms in UVLC systems.

9.
Opt Express ; 32(2): 2561-2573, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297782

RESUMEN

With the advent of the sixth-generation mobile communication standard (6 G), the visible light communication (VLC) technology based on wavelength division multiplexing (WDM) technology can effectively solve the problem of shortage of spectrum resources and insufficient channel capacity. This paper introduces one of our technical achievements, namely the construction of a near-real-time visible light laser communication (VLLC) system based on WDM, which includes a self-designed 10-λ fully-packaged visible light laser emission module, 1 m multimode fiber - 0.175 m free space - 1 m multimode fiber optical transmission link, and receiver array. In the transmitter system, we adopt adaptive discrete multitone (DMT) modulation technique combined with Quadrature Amplitude Modulation (QAM) modulation scheme to obtain maximum spectral efficiency (SE). In the receiving system, we utilize the sparse-structured reservoir computing post-equalization algorithm to achieve superior equalization performance on the basis of the traditional post-equalization algorithm. The experimental results indicate that this quasi-real-time communication system has achieved a signal transmission rate of 113.175Gbps. To the best of our knowledge, this work has set a record in the field of high-speed visible light laser communication. Therefore, the laser communication system constructed by this work, with its flexibility in deployment and high-speed performance, demonstrates the significant potential application of visible light laser communication in data center interconnection and high-speed indoor access networks.

10.
Opt Lett ; 49(7): 1656-1659, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560829

RESUMEN

The escalating surge in datacenter traffic creates a pressing demand for augmenting the capacity of cost-effective intensity modulation and direct detection (IM/DD) systems. In this Letter, we report the demonstration of the single-lane 128-GBaud probabilistically shaped (PS)-PAM-20 IM/DD transmission using only a single digital-to-analog converter (DAC) for a net 400 G/λ system. Based on the advanced digital signal processing (DSP), we achieve net bitrates of up to 437 Gb/s for optical back-to-back and 432 Gb/s after the 0.5-km SSMF transmission in the C-band with 128-Gbaud PS-PAM-20 signals. This work is the latest demonstration on ultra-high-order PS-PAM signals achieving net bitrates exceeding 400 Gb/s despite symbol rate limitations. Notably, to the best of our knowledge, the realized net information rate ([net bitrate]/[symbol rate]) of 3.37 marks a new achievement within the domain of 400 G/λ IM/DD systems, with promising implications for enhancing bandwidth efficiency in the upcoming 1.6-Tb Ethernet scenario.

11.
Opt Lett ; 49(10): 2805-2808, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748166

RESUMEN

The advancement demands of high-speed wireless data link ask for higher requirements on visible light communication (VLC), where wide coverage stands as a critical criterion. Here, we present the design and implementation of a transmitter structure capable of emitting a high-power wide-coverage white light laser. This laser source exhibits excellent stability, with an irradiation range extending to a half-angle of 20°. Its high brightness satisfies the needs of indoor illumination while maintaining excellent communication performance. Utilizing bit-loading discrete multi-tone modulation, a peak data transmission rate of 3.24 Gbps has been achieved, spanning 1 to 5 m. Remarkably, the data rates exceed 2.5 Gbps within a 40° range at a distance of 5 m, enabling a long-distance, wide coverage, high-speed VLC link for future mobile network applications.

12.
Theor Appl Genet ; 137(4): 94, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578443

RESUMEN

KEY MESSAGE: This study revealed the identification of a novel gene, Zm00001d042906, that regulates maize ear length by modulating lignin synthesis and reported a molecular marker for selecting maize lines with elongated ears. Maize ear length has garnered considerable attention due to its high correlation with yield. In this study, six maize inbred lines of significant importance in maize breeding were used as parents. The temperate maize inbred line Ye107, characterized by a short ear, was crossed with five tropical or subtropical inbred lines featuring longer ears, creating a multi-parent population displaying significant variations in ear length. Through genome-wide association studies and mutation analysis, the A/G variation at SNP_183573532 on chromosome 3 was identified as an effective site for discriminating long-ear maize. Furthermore, the associated gene Zm00001d042906 was found to correlate with maize ear length. Zm00001d042906 was functionally annotated as a laccase (Lac4), which showed activity and influenced lignin synthesis in the midsection cells of the cob, thereby regulating maize ear length. This study further reports a novel molecular marker and a new gene that can assist maize breeding programs in selecting varieties with elongated ears.


Asunto(s)
Lacasa , Zea mays , Zea mays/genética , Lacasa/genética , Estudio de Asociación del Genoma Completo , Lignina , Fitomejoramiento
13.
Langmuir ; 40(4): 2320-2332, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38236574

RESUMEN

Water contamination irritated by Cd(II) brings about severe damage to the ecosystem and to human health. The decontamination of Cd(II) by the adsorption method is a promising technology. Here, we construct aminomethylpyridine-functionalized polyamidoamine (PAMAM) dendrimer/apple residue biosorbents (AP-G1.0-AMP and AP-G2.0-AMP) for adsorbing Cd(II) from aqueous solution. The adsorption behaviors of the biosorbents for Cd(II) were comprehensively evaluated. The maximum adsorption capacities of AP-G1.0-AMP and AP-G2.0-AMP for Cd(II) are 1.40 and 1.44 mmol·g-1 at pH 6. The adsorption process for Cd(II) is swift and can reach equilibrium after 120 min. The film diffusion process dominates the adsorption kinetics, and a pseudo-second-order model is appropriate to depict this process. The uptake of Cd(II) can be promoted by increasing concentration and temperature. The adsorption isotherm follows the Langmuir model with a chemisorption mechanism. The biosorbents also display satisfied adsorption for Cd(II) in real aqueous media. The adsorption mechanism indicates that C-N, N═C, C-O, CONH, N-H, and O-H groups participate in the adsorption for Cd(II). The biosorbents display a good regeneration property and can be reused with practical value. The as-prepared biosorbents show great potential for removing Cd(II) from water solutions with remarkable significance.

14.
J Org Chem ; 89(11): 8084-8098, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38810000

RESUMEN

A facile and novel synthetic method for the synthesis of functionalized polycyclic coumarins at the C-4 and C-5 positions is proposed for the first time, which employs copper-catalyzed addition reactions of undiscovered alkenes with difluoromethyl radicals to construct polycyclic coumarins. This strategy is characterized by high regioselectivity, easy availability of raw materials, and simple operation. Additionally, such undiscovered coumarin alkenes can be reacted with a variety of difluoromethyl precursors to obtain a wide range of valuable C-4 and C-5 position functionalized/difluoromethylated polycyclic coumarins. More importantly, some of the products showed significant inhibition of proliferation in vitro against melanoma B16-F10 and lung cancer A549 cell lines with optimal IC50 values of 8.57 and 16.04 µM, respectively.


Asunto(s)
Cobre , Cumarinas , Cumarinas/química , Cumarinas/síntesis química , Catálisis , Cobre/química , Humanos , Estructura Molecular , Proliferación Celular/efectos de los fármacos , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Policíclicos/química , Compuestos Policíclicos/síntesis química
15.
Bioorg Chem ; 151: 107664, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39079392

RESUMEN

Eleven undescribed monoterpenoid bisindole alkaloids, alstomaphyines A-K (1-11), along with three known analogues were isolated from the leaves and stem bark of the Alstonia macrophylla. Compounds 1-3 were unprecedented dimerization alkaloids incorporating a macroline-type motif with an ajmaline-type motif via a C-C linkage. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) calculation, and CD exciton chirality method. Compounds 1-3 displayed potential inhibitory bioactivity against AChE with IC50 values of 4.44 ± 0.35, 3.59 ± 0.18, and 3.71 ± 0.23 µM, respectively. Enzyme kinetic study revealed compounds 1-3 as mixed competitive AChE inhibitors. Besides, compounds 8 and 12-14 exhibited better cytotoxicity against human cancer cell line HT-29 than cisplatin. Flow cytometry data revealed that compounds 8, 13, and 14 significantly induced the HT-29 cells arrest in G0/G1 phase in a concentration-dependent manner.

16.
J Nanobiotechnology ; 22(1): 351, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902789

RESUMEN

Spinal cord injury (SCI) often results in motor and sensory deficits, or even paralysis. Due to the role of the cascade reaction, the effect of excessive reactive oxygen species (ROS) in the early and middle stages of SCI severely damage neurons, and most antioxidants cannot consistently eliminate ROS at non-toxic doses, which leads to a huge compromise in antioxidant treatment of SCI. Selenium nanoparticles (SeNPs) have excellent ROS scavenging bioactivity, but the toxicity control problem limits the therapeutic window. Here, we propose a synergistic therapeutic strategy of SeNPs encapsulated by ZIF-8 (SeNPs@ZIF-8) to obtain synergistic ROS scavenging activity. Three different spatial structures of SeNPs@ZIF-8 were synthesized and coated with ferrostatin-1, a ferroptosis inhibitor (FSZ NPs), to achieve enhanced anti-oxidant and anti-ferroptosis activity without toxicity. FSZ NPs promoted the maintenance of mitochondrial homeostasis, thereby regulating the expression of inflammatory factors and promoting the polarization of macrophages into M2 phenotype. In addition, the FSZ NPs presented strong abilities to promote neuronal maturation and axon growth through activating the WNT4-dependent pathways, while prevented glial scar formation. The current study demonstrates the powerful and versatile bioactive functions of FSZ NPs for SCI treatment and offers inspiration for other neural injury diseases.


Asunto(s)
Antioxidantes , Nanopartículas , Especies Reactivas de Oxígeno , Selenio , Traumatismos de la Médula Espinal , Traumatismos de la Médula Espinal/tratamiento farmacológico , Animales , Antioxidantes/farmacología , Antioxidantes/química , Nanopartículas/química , Ratones , Especies Reactivas de Oxígeno/metabolismo , Selenio/química , Selenio/farmacología , Neuronas/efectos de los fármacos , Ferroptosis/efectos de los fármacos , Ratas , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Células RAW 264.7 , Regeneración Nerviosa/efectos de los fármacos
17.
Sensors (Basel) ; 24(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38894098

RESUMEN

Bolts have the advantages of simple installation and easy removal. They are widely applied in aerospace and high-speed railway traffic. However, the loosening of bolts under mixed loads can lead to nonlinear decreases in pre-loading. This affects the safety performance of the structure and may lead to catastrophic consequences. Existing techniques cannot be used to monitor the bolt performance status in time. This has caused significant problems with the safety and reliability of equipment. In order to study the relaxation law of bolt pre-loading, this paper carries out an experimental analysis for 8.8-grade hexagonal bolts and calibrates the torque coefficient. We also studied different loading waveforms, nickel steel plate surface roughnesses, tangential displacement frequencies, four different strengths and bolt head contact areas of the bolt, the initial pre-loading, and the effects of tangential cyclic displacement on pre-loading relaxation. This was done in order to accurately predict the degree of bolt pre-loading loosening under external loads. The laws are described using the allometric model function and the nine-stage polynomial function. The least squares method is used to identify the parameters in the function. The results show that bolts with a smooth surface of the connected structure nickel steel flat plate, high-frequency working conditions, half-sine wave, and a high-strength have better anti-loosening properties. Taking 5-10 cycles of cyclic loading as a boundary, the pre-loading relaxation is divided into two stages. The first stage is a stage of rapid decrease in bolt pre-loading, and the second stage is the slow decrease process. The performance prediction study shows that the allometric model function is the worst fitted, at 71.7% for the small displacement condition. Other than that, the allometric model function and the nine-stage polynomial function can predict more than 85.5% and 90.4%, which require the use of least squares to identify two and ten unknown parameters, respectively. The complexity of the two is different, but both can by better indicators than the pre-loading relaxation law under specific conditions. It helps to improve the monitoring of bolt loosening and the system use cycle, and it can provide theoretical support for complex equipment working for a long time.

18.
Sensors (Basel) ; 24(10)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38793940

RESUMEN

Mobile visible light communication (VLC) is key for integrating lighting and communication applications in the 6G era, yet there exists a notable gap in experimental research on mobile VLC. In this study, we introduce a mobile VLC system and investigate the impact of mobility speed on communication performance. Leveraging a laser-based light transmitter with a wide coverage, we enable a light fidelity (LiFi) system with a mobile receiving end. The system is capable of supporting distances from 1 m to 4 m without a lens and could maintain a transmission rate of 500 Mbps. The transmission is stable at distances of 1 m and 2 m, but an increase in distance and speed introduces interference to the system, leading to a rise in the Bit Error Rate (BER). The mobile VLC experimental system provides a viable solution to the issue of mobile access in the integration of lighting and communication applications, establishing a solid practical foundation for future research.

19.
J Asian Nat Prod Res ; : 1-7, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38944841

RESUMEN

Four new alkaloids, arecatines A-D (1-4), were isolated from the peels of Areca catechu. Compound 1 is an unusual piperidine-pyridine hybrid alkaloid, whereas compounds 2-4 feature bis-piperidine alkaloids. Their structures were elucidated by UV, IR, HRESIMS, and NMR spectra analysis. The molecular docking analysis indicated that compound 3 exhibited the best binding affinity with the GABAA receptor, indicating its potential anti-epilepsy activity.

20.
Int J Mol Sci ; 25(4)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38396683

RESUMEN

SWEET, sugars will eventually be exported transporter, is a novel class of sugar transporter proteins that can transport sugars across membranes down a concentration gradient. It plays a key role in plant photosynthetic assimilates, phloem loading, nectar secretion from nectar glands, seed grouting, pollen development, pathogen interactions, and adversity regulation, and has received widespread attention in recent years. To date, systematic analysis of the SWEET family in Zantedeschia has not been documented, although the genome has been reported in Zantedeschia elliottiana. In this study, 19 ZeSWEET genes were genome-wide identified in Z. elliottiana, and unevenly located in 10 chromosomes. They were further clustered into four clades by a phylogenetic tree, and almost every clade has its own unique motifs. Synthetic analysis confirmed two pairs of segmental duplication events of ZeSWEET genes. Heatmaps of tissue-specific and Pectobacterium carotovora subsp. Carotovora (Pcc) infection showed that ZeSWEET genes had different expression patterns, so SWEETs may play widely varying roles in development and stress tolerance in Zantedeschia. Moreover, quantitative reverse transcription-PCR (qRT-PCR) analysis revealed that some of the ZeSWEETs responded to Pcc infection, among which eight genes were significantly upregulated and six genes were significantly downregulated, revealing their potential functions in response to Pcc infection. The promoter sequences of ZeSWEETs contained 51 different types of the 1380 cis-regulatory elements, and each ZeSWEET gene contained at least two phytohormone responsive elements and one stress response element. In addition, a subcellular localization study indicated that ZeSWEET07 and ZeSWEET18 were found to be localized to the plasma membrane. These findings provide insights into the characteristics of SWEET genes and contribute to future studies on the functional characteristics of ZeSWEET genes, and then improve Pcc infection tolerance in Zantedeschia through molecular breeding.


Asunto(s)
Pectobacterium , Zantedeschia , Zantedeschia/metabolismo , Proteínas de Plantas/metabolismo , Filogenia , Néctar de las Plantas , Pectobacterium/metabolismo , Regulación de la Expresión Génica de las Plantas
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