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Late spring coldness (LSC) is the main limiting factor threatening wheat yield and quality stability. Optimal nutrient management is beneficial in mitigating the harms of LSC by improving wheat root physiology. This study proposed a nutrient management strategy that postponed the application of phosphorus (P) and potassium (K), effectively strengthening wheat's defense against LSC. This experiment used the winter cultivar "Yannong19" (YN 19) as plant material for two consecutive years (2021–2022 and 2022–2023). Two fertilizer treatments were used: traditional P and K fertilizers application (R1: base fertilizer: jointing fertilizer = 10:0) and postponed P and K fertilizers application (R2: base fertilizer: jointing fertilizer = 5:5); wheat plants at the anther connective formation stage shifted to temperature-controlled phytotrons for normal (T0, 11 °C/4 h) and low temperatures (T1, 4 °C/4 h; T2, −4 °C/4 h) as treatments of LSC. The results showed that under low temperature (LT) treatment, compared with R1, the R2 treatment increased the concentrations of osmotic adjustment substances (soluble sugars and soluble protein contents by 6.2–8.7% and 3.0–8.9%), enhanced activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase activities by 2.2–9.1%, 6.2–9.7% and 4.2–8.4%), balanced the hormone concentrations (increased IAA and GA3 contents by 2.8–17.5% and 10.4–14.1% and decreased ABA contents by 7.2–14.3%), and reduced the toxicity (malondialdehyde, hydrogen peroxide content and O2·− production rate by 5.7–12.4%, 17.7–22.8% and 19.1–19.1%) of the cellular membranes. Furthermore, the wheat root physiology in R2 significantly improved as the root surface area and dry weight increased by 5.0–6.6% and 4.7–6.6%, and P and K accumulation increased by 7.4–11.3% and 12.2–15.4% compared to R1, respectively. Overall, the postponed application of P and K fertilizers enhanced the physiological function of the root system, maintained root morphology, and promoted the accumulation of wheat nutrients under the stress of LSC. [ABSTRACT FROM AUTHOR]

The position of the nozzle in the jet mechanism of the impulse turbine may cause an eccentric jet due to size processing and installation deviations. To study the effect of jet needle eccentricity on the jet, this article first analyzes the jet characteristics of the jet mechanism with different openings (20, 40, 60, 80, 100%) under 4.8% eccentricity, verify the reliability of the research method in this paper. Then the focus is on the jet characteristics of the jet mechanism at different eccentricities (0, 1, 2.1, 4.8, 8, and 14%) at 40% opening. The results show that as the eccentricity of the nozzle increases, the jet appears to be asymmetrical, and the shape of the jet at the inlet section of the runner gradually changes and becomes an irregular shape. The eccentricity of the water jet increases with the increase of the eccentricity of the needle; the efficiency of the injection mechanism gradually decreases, and the energy loss gradually increases. Before the eccentricity of 4.8%, the efficiency decreases more slowly, and after the eccentricity of 4.8%, the rate of efficiency decrease is accelerated.

This paper introduces a new type of flexible rudder surface based on the cosine-type zero Poisson's ratio honeycomb to enhance the adaptive capabilities of aircraft and enable multi-condition, rudderless flight. The zero Poisson's ratio honeycomb structure exhibits exceptional in-plane and out-of-plane deformation capacities, as well as a high load-bearing capability. To investigate the deformation characteristics of flexible rudder surfaces utilizing cosine honeycomb structures, this study undertakes a comprehensive investigation through finite element simulation and 3D printing experiments. Moreover, this study analyzed the impact of honeycomb parameters and layout on the deflection performance and weight. The flexible rudder surface, fabricated from nylon, achieves smooth and consistent chordwise bending deformation, as well as uniform spanwise deformation within a tolerance of ±25°, and the maximum equivalent stress observed was 31.99 MPa, which is within the material's allowable stress limits (50 MPa). Finite element simulation results indicate that once the deflection angle of the rocker exceeds 15°, a discernible deviation arises between the actual deflection angle of the flexible control surface and that of the rocker. Furthermore, this deviation escalates with increasing rocker rotation angles, and this discrepancy can be mitigated by augmenting the number of cosine honeycomb cells within the flexible rudder surface. Finally, a prototype of the flexible rudder surface was successfully produced using 3D printing technology, and the experimental results confirmed the deformation behavior, aligning with simulation outcomes with a deviation of less than 20%. These findings confirm the effective deflection performance of the designed flexible rudder surface, highlighting its potential application in small unmanned aerial vehicles. [ABSTRACT FROM AUTHOR]

The long-term maintenance of low concentration of dissolved oxygen (DO) is an important condition for the enrichment of anammox bacteria (AnAOB) in the electrochemical anammox system (EAS). In this study, a new method to control DO by the combination of sodium sulfite with nitrogen stripping was attempted, and the influence of sodium sulfite concentration on the nitrogen removal performance was studied. The results show that under the optimal conditions (i.e., sodium sulfite concentration = 200 mg/L, nitrogen stripping time = 40–60 min, nitrogen flow = 350 mL/min), the DO in the water was controlled below 0.3 mg/L, which saves more than half of the time required for removing DO compared with the nitrogen stripping method (120–140 min). However, the total nitrogen removal rate (NRR) at the optimal current density of 0.10 mA/cm2 decreased gradually, and the NRR was 0.0091, 0.0061, 0.0026, and 0.0006 g N/[L∙d] at the sodium sulfite concentration of 0, 200, 400, and 600 mg/L, respectively. Simultaneously the specific anammox activity decreased from 0.0077 g N/[g VSS∙d] to 0.0032 g N/[g VSS∙d]. It is concluded that when the current density was 0.10 mA/cm2 and the concentration of sodium sulfite was 200 mg/L, the optimal operating conditions were both anammox activity and deoxidation. Therefore, the combination of sodium sulfite with nitrogen stripping has great application potential to control DO in the EAS. [ABSTRACT FROM AUTHOR]

The development and maturation of sperm entails intricate metabolic processes involving water molecules, amino acids, hormones, and various substances. Among these processes, the role of aquaporins (aqps) in the testis is crucial. Turbot (Scophthalmus maximus) is a significant marine flatfish species in China; however, natural egg laying in females is not feasible under cultured conditions. Consequently, artificial insemination becomes necessary, requiring the retrieval of sperm and eggs through artificial methods. In this study, we combined genomic, transcriptomics, RT-qPCR, computer-assisted sperm analysis (CASA), and immunohistochemistry to investigate the involvement of the aqp family in spermatogenesis in turbot. Through genomic data analysis, we identified 16 aqps genes dispersed across 13 chromosomes, each exhibiting the characteristic major intrinsic protein (MIP) domain associated with AQPs. The results from RNA-seq and RT-qPCR analysis revealed prominent expression of aqp4, 10, and 12 during the proliferative stage, whereas aqp1 showed primary expression during the mature stage. aqp11 displayed high expression levels during both MSII and MSV stages, potentially contributing significantly to the proliferation and maturation of male germ cells. Conversely, aqp8 showed elevated expression levels during the MSIII, MSIII-IV, and MSIV stages, suggesting its direct involvement in spermiogenesis. Immunohistochemical analysis unveiled the predominant localization of AQP1 protein in male germ cells rather than Sertoli cells, specifically concentrated in the head of sperm within cysts. Furthermore, a noteworthy decline in sperm motility was observed when sperm were subjected to treatment with either the AQP1-specific inhibitor (HgCl2) or the AQP1 antibody. However, no direct correlation was found between the expression of Smaqp1 and sperm quality. Overall, these findings provide new insights into the involvement of aqps in teleost spermatogenesis. Moreover, they hold potential for improving techniques related to sperm activation and cryopreservation, offering valuable knowledge for future advancements in this field. [ABSTRACT FROM AUTHOR]

Having a limited number of VH segments, cattle rely on uniquely long DH gene segments to generate CDRH3 length variation (3–70 aa) far greater than that in humans or mice. Bovine antibodies with ultralong CDRH3s (>50 aa) possess unusual structures and abilities to bind to special antigens. In this study, we replaced most murine endogenous DH segments with bovine DH genes, generating a mouse line termed B‐DH. The use of bovine DH genes significantly increased the length variation of CDRH3 and consequently the Ig heavy chain repertoire in B‐DH mice. However, no ultralong CDRH3 was observed in B‐DH mice, suggesting that other factors, in addition to long DH genes, are also involved in the formation of ultralong CDRH3. The B‐DH mice mounted a normal humoral immune response to various antigens, although the B‐cell developmental paradigm was obviously altered compared with wild‐type mice. Additionally, B‐DH mice are not predisposed to the generation of autoantibodies despite the interspecies DH gene replacement. The B‐DH mice reported in this study provide a unique model to answer basic questions regarding the synergistic evolution of DH and VH genes, VDJ recombination and BCR selection in B‐cell development. [ABSTRACT FROM AUTHOR]

To the Editor: Carbapenem resistance in Enterobacteriaceae can occur through the production of carbapenem-hydrolyzing enzymes such as New Delhi metallo-[beta-lactamase-1 (NDM-1) (1). In recent years, plasmid-mediated NDM-1 has spread rapidly [...]

Hypervirulent Klebsiella pneumoniae (hvKp), one of the major community-acquired pathogens, can cause invasive infections such as liver abscess. In recent years, bacteriophages have been used in the treatment of K. pneumoniae , but the characteristics of the phage-resistant bacteria produced in the process of phage therapy need to be evaluated. In this study, two Podoviridae phages, hvKpP1 and hvKpP2, were isolated and characterized. In vitro and in vivo experiments demonstrated that the virulence of the resistant bacteria was significantly reduced compared with that of the wild type. Comparative genomic analysis of monoclonal sequencing showed that nucleotide deletion mutations of wzc and wcaJ genes led to phage resistance, and the electron microscopy and mucoviscosity results showed that mutations led to the loss of the capsule. Meanwhile, animal assay indicated that loss of capsule reduced the virulence of hvKp. These findings contribute to a better understanding of bacteriophage therapy, which not only can kill bacteria directly but also can reduce the virulence of bacteria by phage screening. [ABSTRACT FROM AUTHOR]

In contrast to humans or rabbits, in which maternal IgG is transmitted to offspring prenatally via the placenta or the yolk sac, large domestic animals such as pigs, cows and sheep transmit IgG exclusively through colostrum feeding after delivery. The extremely high IgG content in colostrum is absorbed by newborns via the small intestine. Although it is widely accepted that the neonatal Fc receptor, FcRn, is the receptor mediating IgG transfer across both the placenta and small intestine, it remains unclear whether FcRn also mediates serum IgG transfer across the mammary barrier to colostrum/milk, especially in large domestic animals. In this study, using a FcRn knockout pig model generated with a CRISPR‐Cas9‐based approach, we clearly demonstrate that FcRn is not responsible for the IgG transfer from serum to colostrum in pigs, although like in other mammals, it is involved in IgG homeostasis and mediates IgG absorption in the small intestine of newborns. [ABSTRACT FROM AUTHOR]

Purpose: Acinetobacter baumannii is associated with both hospital-acquired infections and community-acquired pneumonia (CAP). Here, we describe a novel strain of A. baumannii in a case of CAP in a previously healthy rural villager from Central Eastern China. Materials and Methods: A. baumannii isolated from the patient (LS01) was compared to well-characterized pathogenic strain (AB5075), nosocomial circulating strain in China (ZJ06), and wild-type strain (ATCC17978). Growth rate studies were conducted under different environmental stressors, and virulence studies were performed using Galleria mellonella larvae. Whole genome sequencing (WGS) was performed using MinIon and MiSeq. Center for Genomic Epidemiology, CLCbio, Geneious, and Virulence Factors of Pathogenic Bacteria database were used for genomic analysis. Results: LS01 grew significantly faster at 37°C and 42°C and in the presence of zinc compared to other strains. LS01 was more virulent in G. mellonella, killing all larvae within 8 h. Although WGS revealed 44 virulence genes, these genes were also present in the other strains. While two chromosomally encoded β-lactamases were identified, there were no plasmids identified and LS01 was pan-susceptible to all antibiotics tested. Phylogenetic analysis revealed that the closest related strains were only 72.552% identical, supporting a novel strain. Conclusion: LS01 is a novel strain of hypervirulent yet pan-drug susceptible A. baumannii isolated from a patient with no prior hospitalizations, sick contacts, or any of the typical risk factors. This raises concerns for an emerging pathogen, and more epidemiological studies should be conducted to assess the prevalence of this A. baumannii strain. [ABSTRACT FROM AUTHOR]

Background: To investigate the diagnostic efficacy of long noncoding RNA metastasis‐associated in lung adenocarcinoma transcript l (MALAT1) as a candidate serological biomarker for non‐small cell lung cancer (NSCLC). Methods: Diagnostic studies relevant to circulation long noncoding RNA MALAT1 as a candidate serological biomarker for NSCLC were electronically systematically searched in PubMed, EMBASE, EBSCO and CNKI databases. Suitable studies were included in the meta‐analysis by pooling the diagnostic sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (−LR), diagnostic odds ratio (DOR) and area under the symmetric ROC curve (AUC) through a random or fixed effects model. Deeks' funnel plot was applied for publication bias evaluation. Results: Six studies with eight datasets were finally included in the meta‐analysis after a systematic search of the databases was performed. The pooled diagnostic sensitivity, specificity, +LR, −LR and DOR were 0.81 (95% CI:0.78–0.84), 0.67 (95% CI:0.63–0.71), 2.61 (95% CI:1.81–3.71), 0.28 (95% CI:0.19–0.43) and 13.73 (95% CI:6.19–30.44), respectively. The pooled area under the ROC curve (AUC) were 0.8663 and 0.8658, respectively by symmetric and asymmetric methods. Conclusion: Based on the results of our study, serum long noncoding RNA MALAT1 is a promising biomarker for NSCLC screening. However, due to its low specificity, MALAT1 positive cases need further validation for NSCLC by other diagnostic methods such as radiology, cytology, etc. [ABSTRACT FROM AUTHOR]

In order to study the influence of third mediums on the formation and evolution behaviours of rail corrugation, two series of rolling-sliding tests were performed. Firstly, tests under the dry and different third mediums (oil, grease, water, friction modifier and windblown sand) conditions were conducted to study the influence of third mediums on the formation of rail corrugation. Secondly, rail rollers were first rolled under the dry condition until a stable rail corrugation was formed. Then, water and friction modifier were added into the wheel-rail interface to investigate the role of third mediums on the evolution behaviours of rail corrugation. The results indicated that third mediums had a significant influence on the wheel-rail damage and the formation and evolution of rail corrugation. Compared with the dry condition, both the mass losses and the damage of rail rollers were alleviated under third mediums conditions. The continuous application of third mediums at the wheel-rail interface could alleviate the formation of rail corrugation significantly. When non-solid third mediums existed at the wheel-rail interface (oil, grease, water and friction modifier), no corrugation was observed. In the dynamic windblown sand environment, the corrugation was obviously slighter than that under the dry contact condition. After corrugation was formed on the rail roller, the application of water and friction modifier could alleviate the amplitude of rail corrugation. Furthermore, with the increase in the number of cycles, the amplitude of rail corrugation first increased and then remained nearly stable. Under the dry contact condition, the crack length in the trough was larger than that in the crest. When liquid third mediums were applied, the cracks at the crest were ground away. However, some liquid would enter into the pre-existed crack in the trough, resulting in the severe rolling contact fatigue damage of rail. • The influence of different third mediums on the generation and evolution of rail corrugation was studied. • The third medium (water, oil, grease, FM) could alleviate the generation of rail corrugation. • The application of third mediums, especially water, would result in the reduction of the amplitude of rail corrugation, the transition from oxidative wear to fatigue wear in the crest and severe fatigue damage in the trough. • The influence mechanism of third mediums on the development of rail corrugation was proposed. [ABSTRACT FROM AUTHOR]

Background: The occurrence of non-contiguous, multiple, and remote involvement tuberculous spondylitis is rare. The clinical presentation in patients with multifocal musculoskeletal tuberculosis may closely mimic that in patients with multiple bone metastases, which makes the accurate clinical diagnosis challenging. Herein, we report a multifocal musculoskeletal tuberculosis case that was misdiagnosed for 8 months as multiple bone metastases.Case Presentation: A 63-year-old male farmer of Chinese Han ethnicity presented to us with pain in left side of the neck, right side of the chest and the back for 10 months without typical tuberculosis symptoms. His past medical history, the CT and fluoroscopy-guided biopsy were negative for tuberculosis. Interferon gamma by T-SPOT was also negative. Radiological findings including CT, MRI and PET-CT suggested that the patient had multiple metastases. Accordingly, the patient was misdiagnosed as having musculoskeletal tumors until a swelling under the right nipple ulcerated. The smear test for acid-fast bacilli and the PCR test for TB-DNA of the pus from the swollen area were both positive, leading to the final correct diagnosis of musculoskeletal tuberculosis.Conclusion: The proper diagnosis of musculoskeletal tuberculosis is clinically challenging due to Mycobacterium tuberculosis variants involved and atypical presentations, especially when the lesions are multiple. Our findings indicate that multiple tuberculous spondylitis must be considered in the differential diagnosis of multiple musculoskeletal lesions. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) are a cluster of enzymes that degrade the extracellular matrix (ECM) and some intracellular proteins; as such, they play an important role in tissue regeneration, infant growth, animal reproduction, and immunity. Most research into MMPs focuses mainly on their effects on the mammalian immune system. However, it is not clear how MMPs affect immune processes in crustaceans. Here, we cloned the open reading frame (ORF) of Eriocheir sinensis (Chinese mitten crab) MMP-14 (EsMMP-14) to explore the role of MMPs in crustacean innate immune responses. RT-PCR results showed that stimulation of crab with LPS and poly I:C upregulated expression of EsMMP-14 markedly. Besides, following the stimulation of 20-Hydroxyecdysone, the expression level of EsMMP-14 increased robustly, suggesting that EsMMP-14 involved in the molt process of E. sinensis. Hematoxylin and eosin staining of hepatopancreas and intestine revealed that knocking down EsMMP-14 maintained morphology following infection by Bacillus thuringiensis. Moreover, downregulated expression of EsMMP-14 increased the survival rate of infected E. sinensis. These results show that EsMMP-14 plays a role in innate immune responses of E. sinensis and fills a gap in our knowledge about the function of MMPs in crustaceans. • LPS and poly I:C stimulation induced overexpression of EsMMP-14. • EsMMP-14 expressed robustly following the stimulation of 20-Hydroxyecdysone. • RNAi of EsMMP-14 maintained normal tissue morphology following infection. • RNAi of EsMMP-14 increased the survival rate of infected E. sinensis. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the antimicrobial susceptibilities and prevalence of plasmid-mediated quinolone resistance determinants amongst Salmonella enterica serotype Typhimurium isolates from hospitalised paediatric patients with diarrhoea in China were investigated. In total, 40 (64.5%) of 62 S. Typhimurium isolates were resistant to ciprofloxacin (minimum inhibitory concentration ≥0.5μg/mL), comprising 28 isolates with low-level resistance and 12 isolates with high-level resistance. All ciprofloxacin-resistant isolates were multiresistant to other antimicrobial agents. Four pulsed-field gel electrophoresis (PFGE) clusters were found amongst the 40 ciprofloxacin-resistant isolates, amongst which PFGE clusters A, B, E and D accounted for 7, 4, 1 and 28 isolates, respectively. Two isolates with high-level ciprofloxacin resistance had two mutations in the quinolone resistance-determining regions (QRDRs) of gyrA and parC. The remaining ciprofloxacin-resistant isolates had only one mutation in the QRDR of gyrA. All 62 S. Typhimurium isolates were negative for qnr genes and qepA and 23 (37.1%) of the isolates were positive for aac(6′)-Ib-cr. Nineteen isolates harbouring aac(6′)-Ib-cr belonged to PFGE cluster D. A high prevalence of ciprofloxacin resistance and aac(6′)-Ib-cr was found amongst S. Typhimurium isolates in China from hospitalised paediatric patients with diarrhoea not receiving quinolones. A single mutation in the QRDR of gyrA as well as production of AAC(6′)-Ib-cr contributed to ciprofloxacin resistance. Clonal spread was responsible for the dissemination of aac(6′)-Ib-cr amongst S. Typhimurium isolates. [ABSTRACT FROM AUTHOR]

The article offers information on a study concerning the prevalence of mobilized colistin resistance (mcr-1)-producing Klebsiella pneumoniae in bloodstream infections in China. Topics discussed include determination of minimum inhibitory concentration (MIC) of MCR-1 positive isolates using the broth microdilution method; use of filter-mating method for conjugation experiments Escherichia coli J53 as the recipient strain; and mentions that whole-genome sequencing (WGS) was performed.