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Potatoes are widely planted worldwide and are the third most important food crop. Mutation breeding involves the artificial use of various physical and chemical factors to induce plants to produce new genotypes. In this study, we established a potato radiation mutation system and analysed the features of a radiation mutant. The LD50 of the potato callus was 24.8 Gy after linear regression analysis. The radiation mutant 1 (RM1) showed significant dwarfism and strong growth; RM1 plants decreased in height by 31%. The root and leaf fresh weights of the RM1 increased 1.8-fold compared to the wild-type (WT, Chuanyu 10) cultivar. Leaf microstructure results showed that the thicknesses of the upper epidermis and lower epidermis of RM1 plants were greater than those of the WT cultivar. Transcriptome analysis of seeding revealed 1179 upregulated and 1641 downregulated differentially expressed genes (DEGs) in RM1 plants. Further analysis showed that the expression levels of WRKY and MYB transcription factors, CIPK and MAPK protein kinases, ABC transporters, hormones, and ROS pathway genes were altered. These results provide theoretical support for potato breeding research and enrich the functional network of vital breeding-related genes. [ABSTRACT FROM AUTHOR]

Ureide permeases (UPSs) mediate the transport of ureides, including allantoin and allantoate, which act as nitrogen-transporting compounds in plants and have recently been found to play a role in cellular signaling. To date, UPSs have not been reported in potato, and their identification is important for further function studies and for understanding molecular mechanisms of plant adverse responses. Based on potato genomic data, we identified 10 StUPS genes in potato (Solanum tuberosum L.). Then, we conducted a comprehensive study of the identified StUPS genes using bioinformatics methods. Genome phylogenetic and genomic localization analyses revealed that StUPSs can be classified into four categories, are highly homologous to Arabidopsis thaliana UPS members, and are distributed on three chromosomes. The six StUPS genes were investigated by RT–qPCR, and the findings indicated that all of these genes are involved in the response to several stresses, including low nitrogen, cold, ABA, salt, H2O2, and drought. This study establishes a strong theoretical framework for investigating the function of potato UPS genes, as well as the molecular mechanisms underlying the responses of these genes to various environmental stresses. [ABSTRACT FROM AUTHOR]

The BTB/POZ (broad-complex, tramtrack, and bric-a-brac) family of proteins is widespread in plants and animals and plays important roles in growth, development, metabolism, and environmental responses. There are few reports on BTB family genes in potato. In this study, 34 sequences containing conserved BTB domains were obtained from the potato gene database, and the phylogenetic, physical, and chemical properties, gene structure, conserved motif, domain, and chromosomal localization of the potato BTB protein family were analyzed via bioinformatics methods. In addition, we used qRT-PCR to detect 12 selected StBTB genes. The results confirmed that these genes are involved in cold, ABA, salt, hydrogen peroxide (H2O2), drought, and low-nitrogen stress, which is highly important for elucidating BTB family members and studying stress response and tolerance mechanisms. This study provides a theoretical basis for the study of the function and expression of potato BTB and lays a solid foundation for further understanding the molecular mechanism of the potato BTB gene under various environmental stresses. [ABSTRACT FROM AUTHOR]

CBL-interacting protein kinases (CIPKs) play important regulatory roles in plant growth development and abiotic stress tolerance. However, the biological roles of these genes in response to low-nitrate (LN) stress in potato plants have not been determined. Here, we reported that StCIPK23 was expressed mainly in roots and leaves. StCIPK23 was located mainly in the cell membrane, nucleus, and cytoplasm. Further research suggested that, compared with wild-type (WT) plants, StCIPK23-overexpressing plants were taller and had significantly greater nitrate and ammonium nitrogen contents under LN stress. StCIPK23 overexpression can increase StAT, StNRT2.1, StNR, StGS1-3, and StGOGAT expression levels in StCIPK23 transgenic seedlings compared to those in WT plants under LN stress. The results of yeast two-hybrid and luciferase complementation imaging experiments suggested that StCIPK23 could interact with StCBL3. Real-time reverse transcription–PCR revealed the StCIPK23 expression level peaked at 6 h and the StCBL3 expression level peaked at 9 h in the roots under LN stress. In conclusion, we found that StCIPK23 and StCBL3 form a complex to regulate the expression of key genes in the nitrogen metabolism pathway to improve LN tolerance in potato plants. [ABSTRACT FROM AUTHOR]

To examine the effectiveness of azvudine and nirmatrelvir–ritonavir in treating hospitalized patients with moderate‐to‐severe COVID‐19. We emulated a target trial with a multicenter retrospective cohort of hospitalized adults with moderate‐to‐severe COVID‐19 without contraindications for azvudine or nirmatrelvir–ritonavir between December 01, 2022 and January 19, 2023 (during the Omicron BA.5.2 variant wave). Exposures included treatment with azvudine or nirmatrelvir–ritonavir for 5 days versus no antiviral treatment during hospitalization. Primary composite outcome (all‐cause death and initiation of invasive mechanical ventilation), and their separate events were evaluated. Of the 1154 patients, 27.2% were severe cases. In the intent‐to‐treat analyses, azvudine reduced all‐cause death (Hazard ratio [HR]: 0.31; 95% CI: 0.12–0.78), and its composite with invasive mechanical ventilation (HR: 0.47; 95% CI: 0.24–0.92). Nirmatrelvir–ritonavir reduced invasive mechanical ventilation (HR: 0.42; 95% CI: 0.17–1.05), and its composite with all‐cause death (HR: 0.38; 95% CI: 0.18–0.81). The study did not identify credible subgroup effects. The per–protocol analyses and all sensitivity analyses confirmed the robustness of the findings. Both azvudine and nirmatrelvir–ritonavir improved the prognosis of hospitalized adults with moderate‐to‐severe COVID‐19 [ABSTRACT FROM AUTHOR]

Because the magnetic signal information of pipeline defects obtained by magnetic flux leakage detection contains interference signals, it is difficult to accurately extract the features. Therefore, a novel pipeline defect feature extraction method based on VMD-OSVD (variational modal decomposition - optimal singular value decomposition) is proposed to promote the signal to noise ratio (SNR) and reduce aliasing in the frequency domain. By using the VMD method, the sampled magnetic signal is decomposed, and the optimal variational mode is selected according to the rate of relative change (VMK) of Shannon entropy (SE) to reconstruct the signal. After that, SVD algorithm is used to filter the reconstructed signal again, in which the H-matrix is optimized with the phase-space matrix to enhance SNR and decrease the frequency domain aliasing. The results show that the method has excellent denoising ability for defect magnetic signals, and SNR is increased by 21.01%, 24.04%, 0.96%, 32.14%, and 20.91%, respectively. The improved method has the best denoising effect on transverse mechanical scratches, but a poor denoising effect on spiral welding position. In the frequency domain, the characteristics of different defects are varied, and their corresponding frequency responses are spiral weld corrosion > transverse mechanical cracking > girth weld > deep hole > normal pipe. The high-frequency band is the spiral weld corrosion with f1 -153.37 Hz. The low-frequency band is normal with f2 - 1 Hz. In general, the VMD-OSVD method is able to improve the SNR of the signal and characterize different pipe defects. And it has a certain guiding significance to the application of pipeline inspection in the field of safety in the future. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the role and mechanism of action of ribonucleotide reductase M2 (RRM2) in lung adenocarcinoma and its potential as a therapeutic target. Data of patients with lung adenocarcinoma from The Cancer Genome Atlas database were collected and analyzed to evaluate the potential of RRM2 as a biomarker. The expression of RRM2 was evaluated in the A549 cell line and its cisplatin-resistant A549/DDP cell line derivative by western blot and reverse transcription-quantitative PCR. The study also investigated cell proliferation and the mechanism by which RRM2 controls cellular cisplatin resistance using CCK-8 and colony-formation assays. In addition, cell migration was assessed using Transwell assays, and the cell cycle and apoptosis were examined using flow cytometry. RRM2 was highly expressed in lung adenocarcinoma and was associated with the clinical TMN stage. Functional enrichment analysis showed that RRM2 was enriched in the cell cycle. Immune cell infiltration analysis identified 12 types of immune cell that exhibited differences between patients expressing different levels of RRM2. Cellular assays revealed higher levels of RRM2 expression in A549/DDP cells than A549 cells, and its expression was induced by cisplatin. RRM2 knockdown decreased cell proliferation and migration, accelerated apoptosis and caused cell cycle arrest in the S-phase, increasing the sensitivity of A549 and A549/DDP cells to cisplatin through the Wnt/β-catenin signaling pathway. Overexpression of β-catenin reduced the effects of RRM2 knockdown on A549 cells. Lung adenocarcinoma growth may be influenced by RRM2 through the Wnt/β-catenin signaling pathway, suggesting a potential pathway for cancer progression. [ABSTRACT FROM AUTHOR]

Unidirectional transports have been observed in two-dimensional systems, however, so far they have not been experimentally observed in three-dimensional bulk materials. In this theoretical work, we show that the recently discovered Weyl materials provide a platform for unidirectional transports inside bulk materials. With high experimental feasibility, a complex Dirac mass can be generated and manipulated in photonic Weyl crystals, creating unidirectionally propagating modes observable in transmission experiments. A possible realization in (electronic) Weyl semimetals is also studied. We show in a lattice model that, with a short-range interaction, the desired form of the Dirac mass can be spontaneously generated in a first-order transition. [ABSTRACT FROM AUTHOR]

While a high osmolarity medium activates Cpx signaling and causes CpxR to repress csgD expression, and efflux protein TolC protein plays an important role in biofilm formation in Escherichia coli, whether TolC also responds to an osmolarity change to regulate biofilm formation in extraintestinal pathogenic E. coli (ExPEC) remains unknown. In this study, we constructed ΔtolC mutant and complement ExPEC strains to investigate the role of TolC in the retention of biofilm formation and curli production capability under different osmotic conditions. The ΔtolC mutant showed significantly decreased biofilm formation and lost the ability to produce curli fimbriae compared to its parent ExPEC strain PPECC42 when cultured in M9 medium or 1/2 M9 medium of increased osmolarity with NaCl or sucrose at 28°C. However, biofilm formation and curli production levels were restored to wild-type levels in the ΔtolC mutant in 1/2M9medium. We propose for the first time that TolC protein is able to formbiofilm even under high osmotic stress. Our findings reveal an interplay between the role of TolC in ExPEC biofilm formation and the osmolarity of the surrounding environment, thus providing guidance for the development of a treatment for ExPEC biofilm formation. [ABSTRACT FROM AUTHOR]

Background: Failure of bioprosthetics is usually caused by calcification of the leaflets as a consequence of high tensile stresses. The stentless valve resembles native mitral valve anatomy, has a flexible leaflet attachment and a suspension at the papillary muscles, and preserves annuloventricular continuity. In this study, the effects of the stentless valve design on leaflet stress were investigated with a finite element model. Methods: Finite element models of the stentless quadrileaflet mitral valve were created in the close and open configurations. The geometry of the stented trileaflet mitral valve was also analyzed for comparative purposes. Under the designated pressures, the regional stresses were evaluated, and the distributions of stresses were assessed. Results: Regardless of whether the valve is in the open or close configuration, the maximum first principal stress was significantly lower in the stentless valve than in the stented valve. For the stentless valves, limited stress concentration was discretely distributed in the papillary flaps under both close and open conditions. In contrast, in the stented valve, increased stress concentration was evident at the central belly under the open condition and at the commissural attachment under close condition. In either configuration, the maximum second principal stress was markedly lower in the stentless valve than in the stented valve. Conclusions: The stentless valve was associated with a significant reduction in leaflet stress and a more homogeneous stress distribution compared to the stented valve. These findings are consistent with recent reports of the clinical effectiveness of the stentless quadrileaflet mitral valve. [ABSTRACT FROM AUTHOR]

Background: Tibial dyschondroplasia (TD) is a common skeletal disorder in broiler chickens. It is characterized by the presence of a non-vascularized and unmineralized cartilage in the growth plate. Previous studies have investigated differential expression of genes related to cartilage development during latter stages of TD. The aim of our study was to identify differentially expressed genes (DEGs) in the growth plate of broiler chickens, which were associated with early stage TD. We induced TD using tetramethylthiuram disulfide (thiram) for 1, 2, and 6 days and determined DEGs with chicken Affymetrix GeneChip assays. The identified DEGs were verified by quantitative polymerase chain reaction (qPCR) assays. Results: We identified 1630 DEGs, with 82, 1385, and 429 exhibiting at least 2.0-fold changes (P < 0.05) at days 1, 2, and 6, respectively. These DEGs participate in a variety of biological processes, including cytokine production, oxidation reduction, and cell surface receptor linked signal transduction on day 1; lipid biosynthesis, regulation of growth, cell cycle, positive and negative gene regulation, transcription and transcription regulation, and antiapoptosis on day 2; and regulation of cell proliferation, transcription, dephosphorylation, catabolism, proteolysis, and immune responses on day 6. The identified DEGs were associated with the following pathways: neuroactive ligand-receptor interaction on day 1; synthesis and degradation of ketone bodies, terpenoid backbone biosynthesis, ether lipid metabolism, JAK-STAT, GnRH signaling pathway, ubiquitin mediated proteolysis, TGF-β signaling, focal adhesion, and Wnt signaling on day 2; and arachidonic acid metabolism, mitogen-activated protein kinase (MAPK) signaling, JAK-STAT, insulin signaling, and glycolysis on day 6. We validated seven DEGs by qPCR. Conclusions: Our findings demonstrate previously unrecognized changes in gene transcription associated with early stage TD. The DEGs we identified by microarray analysis will be used in future studies to clarify the molecular pathogenic mechanisms of TD. From these findings, potential pathways involved in early stage TD warrant further investigation. [ABSTRACT FROM AUTHOR]

In this paper, a novel generalized discontinuous space-vector pulse width modulation (DSVPWM) strategy called DSVPWMx, which includes DSVPWMP, DSVPWMN, DSVPWMPN0, DSVPWMPN1, DSVPWMPN2, and DSVPWMPN3, is proposed for three-phase voltage source inverters. Six sectors are redivided into 12 ones based on space-vector pulse width modulation (SVPWM) and local over modulation method. The principle of the new DSVPWMx is developed, essential relationship among different DSVPWMx strategies and linear modulation ranges of DSVPWMx are discussed. The characteristics for DSVPWMx and the traditional discontinuous pulse width modulation (DPWM) strategies such as DPWMMAX, DPWMMIN, DPWM0, DPWM1, DPWM2, and DPWM3 named as DPWMx are studied on the basis of harmonic distortion and switching loss. The simulation and experimental results verify that the DSVPWMx strategies are right and feasible. [ABSTRACT FROM PUBLISHER]

A new digital phase-locked-loop (DPLL) method is proposed for single-phase grid-connected power conversion systems in this paper. The analysis of a phase detector using trigonometric function transformation is presented in detail. A sliding-window-based data sampling method is utilized to obtain the orthogonal signal related to the original input signal according to the periodic characteristic of the steady-state sine fundamental component, and the fictitious active and reactive power components are constructed. On this basis, the DPLL method is developed. It consists of an even harmonics elimination network, a grid voltage feedforward network, and a fictitious instantaneous power feedback phase correction network. The fundamental signal of the grid voltage is extracted by an even harmonics elimination network and a digital Butterworth filter and a unit value controller to generate a unity sine reference signal for the feedforward network, whereas only the signs of the fictitious instantaneous active and reactive powers are used to revise the phase shift of the unity sine reference signal by means of a real-time variable step-size control in the feedback phase correction network. The method is validated to have good dynamic and static performances through MATLAB simulations, simulator investigations, and experiments with a grid-connected photovoltaic system under different voltage conditions. [ABSTRACT FROM PUBLISHER]

Topological nodal-line semimetals are characterized by one-dimensional lines of band crossing in the Brillouin zone. In contrast to nodal points, nodal lines can be in topologically nontrivial configurations. In this Rapid Communication, we introduce the concept of "nodal-knot semimetals," whose nodal lines form topologically nontrivial knots in the Brillouin zone. We introduce a generic construction of nodal-knot semimetals, which yields the simplest trefoil nodal knot and other more complicated nodal knots. The knotted-unknotted transitions by nodal-line reconnections are also studied. Our work brings the knot theory to the subject of topological semimetals. [ABSTRACT FROM AUTHOR]

In topological semimetals, the valance band and conduction band meet at zero-dimensional nodal points or one-dimensional nodal rings, which are protected by band topology and symmetries. In this Rapid Communication, we introduce "nodal-link semimetals", which host linked nodal rings in the Brillouin zone. We put forward a general recipe based on the Hopf map for constructing models of nodal-link semimetals. The consequences of nodal ring linking in the Landau levels and Floquet properties are investigated. [ABSTRACT FROM AUTHOR]

Backscattering-immune chiral modes arise along certain line defects in three-dimensional materials. Here, we study the Floquet chiral modes along Floquet topological defects, namely, the defects come entirely from spatial modulations of periodic driving. We define a precise topological invariant that counts the number of Floquet chiral modes, which is expressed as an integral on a five-dimensional torus parametrized by (kx,ky,kz,θ,t). This work demonstrates the possibility of creating chiral modes in three-dimensional bulk materials by modulated driving. [ABSTRACT FROM AUTHOR]

Majorana zero modes are usually attributed to topological superconductors. We study a class of two-dimensional topologically trivial superconductors without chiral edge modes, which nevertheless host robust Majorana zero modes in topological defects. The construction of this minimal single-band model is facilitated by the Hopf map and the Hopf invariant. This work will stimulate investigations of Majorana zero modes in superconductors in the topologically trivial regime. [ABSTRACT FROM AUTHOR]

The article presents a study on the preparation and gene cloning of high-specific anti-porcine haptoglobin (Hp) monoclonal antibodies through the use of the recombinant expressive porcine Hp protein that resulted into the establishment of 3B4 and 3C8 hybridoma cell lines.