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The SARS-CoV-2 and its variants are still hitting the world. Ever since the outbreak, neurological involvements as headache, ageusia, and anosmia in COVID-19 patients have been emphasized and reported. But the pathogenesis of these new-onset neurological manifestations in COVID-19 patients is still obscure and controversial. As difficulty always lay in the diagnosis of neurological infection, current reports to validate the presence of SARS-CoV-2 in cerebrospinal fluid (CSF) almost relied on the basic methods and warranted improvement. Here we reported a case series of 8 patients with prominent new-onset neurological manifestations, who were screened out from a patch of 304 COVID-19 confirmed patients. Next-generation sequencing (NGS) and proteomics were conducted in the simultaneously obtained CSF and serum samples of the selected patients, with three non-COVID-19 patients with matched demographic features used as the controls for proteomic analysis. SARS-CoV-2 RNA was detected in the CSF of four COVID-19 patients and was suspicious in the rest four remaining patients by NGS, but was negative in all serum samples. Proteomic analysis revealed that 185 and 59 proteins were differentially expressed in CSF and serum samples, respectively, and that only 20 proteins were shared, indicating that the proteomic changes in CSF were highly specific. Further proteomic annotation highlighted the involvement of complement system, PI3K-Akt signaling pathway, enhanced cellular interaction, and macrophages in the CSF proteomic alterations. This study, equipped with NGS and proteomics, reported a high detection rate of SARS-CoV-2 in the CSF of COVID-19 patients and the proteomic alteration of CSF, which would provide insights into understanding the pathological mechanism of SARS-CoV-2 CNS infection.

Engagement in early childhood has been linked with later achievement, but the relation between these variables and how they are measured in early childhood requires examination. We estimated the overall association between academic engagement and achievement in children prior to kindergarten entry. Our systematic literature search yielded 13,521 reports for structured eligibility screening; from this pool of studies, we identified 21 unique data sets, with 199 effect sizes for analysis. We coded eligible studies, extracted effect sizes, accounted for effect size dependency, and used random-effects models to synthesize findings. The overall correlation between academic engagement and achievement was r = 0.24 (range: -0.08 to 0.71), and moderator analyses did not significantly predict the relation between the two constructs. This study aligns with previous research on this topic and examines issues related to these measures, their constraints, and applications as they pertain to early childhood research.

Purpose: The purposes of this meta-review are to (a) articulate the importance of transparency and reproducibility in meta-analysis, (b) assess the transparency and reproducibility of meta-analyses published in journals of the American Speech-Language-Hearing Association (ASHA), and (c) discuss the implications of our findings and recommendations for future research. Method: We conducted a meta-review of all meta-analyses published in ASHA journals through December 31, 2020. Our systematic review yielded 47 meta-analyses for inclusion in this review. We coded all eligible reports on the core elements of transparency and reproducibility in meta-analysis. Results: Our findings suggest that though reporting tendencies have improved over time, much work is needed to promote transparency and reproducibility in meta-analytic work. Key areas for future accountability include preregistering study protocol, using Preferred Reporting in Systematic Reviews and Meta-Analysis checklists, providing full data sets, and publishing analytic codes. Conclusions: The state of reporting in meta-analysis is improving over time. We conclude with a discussion of specific areas that need further attention, and recommendations for researchers to consider when conducting future meta-analyses.

Background: Pulse wave, as a carrier of human hemodynamic parameters, can reflect the hemodynamic state of the menstrual cycle. Objective: To explore the influence of pulse wave shape and pulse rate variation on menstrual cycle and dysmenorrhea. Methods: The pulse waveform data of 20 women during the whole menstrual cycle were collected and monitored, and the waveform characteristics and pulse rate variation characteristics were calculated. Results: The characteristic parameters of waveform and pulse rate variation increased first and then decreased with the development of the menstrual cycle. Characteristics were associated with dysmenorrhea at different stages of the menstrual cycle. Conclusions: The findings of this study highlight the physiological significance of pulse wave characteristics and heart rate variability parameters in relation to the menstrual cycle and dysmenorrhea. These results provide new insights into the physiological mechanisms underlying pulse wave changes during the menstrual cycle and offer potential guidance for the diagnosis and treatment of dysmenorrhea.

In order to understand the establishment of oil pipeline scheduling model and interface tracking calculation method, a research on the establishment of a universal product oil pipeline scheduling model and interface tracking calculation method has been proposed. Establish an automatic formulation and optimization model for the scheduling plan of finished oil pipelines with the objective of minimizing the consumption cost of the entire pump unit. The model mainly adopts a centralized distribution method, considering the hydraulic constraints of the pipeline, and adopts a genetic algorithm to optimize and solve the model. This article provides a detailed introduction to the encoding method of genetic algorithm for optimizing the scheduling plan of finished oil pipelines, the selection of main operators in the algorithm, the establishment of fitness functions, and the introduction of penalty functions. Based on the established mathematical model, an automatic programming and optimization program for product oil pipeline scheduling plan was developed using C language in Windows 7 environment. Secondly, through practical applications, the actual pipeline operation data is basically consistent with the software calculation results, with an error of no more than 5%; As the running time changes, the pump cost fluctuates greatly; Using a larger throughput can reduce the amount of mixed oil; Therefore, this mathematical model can better meet the actual needs of pipeline operation, facilitate the rapid identification of the most sensitive parameter indicators, and adjust the scheduling plan in a timely manner, reduce operational economic losses, and improve the efficiency of product oil pipeline scheduling and operation.

The overarching goal of this 2-phase study was to investigate the contributions of relational reasoning to mathematical thinking and performance for 790 primary and middle-school Chinese students. Phase I of the study was undertaken to establish the reliability and validity of the Test of Relational Reasoning-Junior (TORRjr), a 32-item measure developed to assess children's and young adolescents' ability to reason analogically, anomalously, antinomously, and antithetically. The range of analyses from item difficulties to the overall structural model showed the TORRjr to be a psychometrically sound measure for study participants. There was also evidence of development in students' relational reasoning ability. In Phase II, the contributions of TORRjr performance to results of a novel measure of quantitative relations (QRTC[superscript 2]), a traditional measure of mathematical ability (MAT), and a fluid measure of mental rotation (MRT) were examined. Relational reasoning was significantly associated with performance on all 3 measures to a moderate or moderately strong level. Relational reasoning was also found to partially mediate the association between the QRTC[superscript 2] and MAT and fully mediate the relation between MRT and MAT. Multiple-group regression analyses revealed a stronger association between relational reasoning and mathematical performance for middle-school students than for primary students. Theoretical and practical implications of the outcomes from both phases are forwarded.

ObjectiveTo develop plasmid DNA reference materials that can be used for polymyxin antibiotic resistance encoding genes rapid detection.MethodsThe reference sequence of mcr­1， mcr­3 and mcr­5 were retrieved from the National Center for Biotechnology Information to construct recombinant plasmids and strains. The recombinant strains were subcultured for 15 generations to detect the genetic stability of the target gene. The recombinant plasmid was extracted and vacuum dried to prepare the standard sample. The limit of detection （LOD） of PCR and RT­qPCR was determined after the standard sample was hydrated and continuously diluted with 10­fold gradient， respectively. Multi­tube plasmid DNA standard samples were randomly selected to qualitatively and quantitatively evaluate the uniformity and storage stability at 4 ℃， 37 ℃ and -20 ℃ by PCR and UV spectrophotometer.ResultsFragments of mcr­1， mcr­3 and mcr­5 that encoding polymyxin resistance mechanism were successfully obtained. Target genes in the recombinant strains could stably inherited after subcultured for 15 generations. The LOD of PCR and RT­qPCR of mcr­1， mcr­3 and mcr­5 standard samples were 1.67×104 and 1.67 copies/μL， 1.31×104 and 13.1 copies/μL， 1.55×105 and 1.55 copies/μL， respectively. The mass F values of 12 standard samples randomly selected for each gene were all less than the F critical value， each gene could be detected by RT­qPCR and indicating that the uniformity of the samples met the requirements. When standard samples were stored at 4 ℃ for 90 d， 37 ℃ for 14 d and -20 ℃ for 360 d， the qualitative and quantitative test result showed it was stable without significant difference.ConclusionIn this study， plasmid DNA standard samples that carrying mcr­1， mcr­3 and mcr­5 were prepared. The target genes could be stably inherited， the standard samples had good uniformity and storage stability， and could be used as a quality control samples for polymyxin antibiotics resistance encoding genes detection and mechanisms prediction.

Parasitic side reactions and dendrite growth on zinc anodes are formidable issues causing limited lifetime of aqueous zinc ion batteries (ZIBs). Herein, a spontaneous cascade optimization strategy is first proposed to regulate Zn2+ migration‐diffusion behavior. Specifically, PAPE@Zn layer with separation‐reconstruction properties is constructed in situ on Zn anode. In this layer, well‐soluble poly(ethylene oxide) (PEO) can spontaneously separation to bulk electrolyte and weaken the preferential coordination between H2O and Zn2+ to achieve primary optimization. Meanwhile, poor‐soluble polymerized‐4‐acryloylmorpholine (PACMO) is reconstructed on Zn anode as hydrophobic flower‐like arrays with abundant zincophilic sites, further guiding the de‐solvation and homogeneous diffusion of Zn2+ to achieve the secondary optimization. Cascade optimization effectively regulates Zn2+ migration‐diffusion behavior, dendrite growth and side reactions of Zn anode are negligible, and the stability is significantly improved. Consequently, symmetrical cells exhibit stability over 4000 h (1 mA cm−2). PAPE@Zn//NH4+−V2O5 full cells with a high current density of 15 A g−1 maintains 72.2 % capacity retention for 12000 cycles. Even better, the full cell demonstrates excellent performance of cumulative capacity of 2.33 Ah cm−2 at ultra‐low negative/positive (N/P) ratio of 0.6 and a high mass‐loading (~17 mg cm−2). The spontaneous cascade optimization strategy provides novel path to achieve high‐performance and practical ZIBs. [ABSTRACT FROM AUTHOR]

This paper employs the Finite Element Method (FEM) to simulate and analyze the effects of corrosion defect parameters on the stress and failure pressure of pipelines. It investigates how the boundary conditions of the pipeline model influence stress and examines the sensitivity of failure pressure to corrosion defect parameters. A nonlinear regression equation has been developed from a dataset obtained through simulation experiments to predict the failure pressure of corroded pipelines. To validate the effects of corrosion defect parameters on failure pressure, a hydrostatic test platform for an API 5L X65 pipeline with corrosion defects was established to measure stress levels and failure pressures across varying corrosion defects. This study reveals that failure pressure is negatively correlated with corrosion length and depth, while positively correlated with corrosion width. Among these parameters, corrosion depth exerts a more significant influence on the pipeline's failure pressure than corrosion length and width. Within the range of corrosion defect parameters examined, the maximum deviation of the prediction equation's results from the simulation results is 8.71%, with an average deviation of 5.81%. The standard deviation of the fitted residuals is 0.01837. Additionally, the maximum deviation between the predicted results and experimental measurements is 8.39%, with an average deviation of 7.77%. The strong agreement between the predicted results from the equation and the actual measured data underscores the effectiveness of the nonlinear regression equation. [ABSTRACT FROM AUTHOR]

Charge and energy transfers among Mn2+ ions determine the excited‐state dynamics in Mn2+‐based phosphors, which modulate the luminescence properties in various applications. However, in crystals with dense Mn2+ ions, luminescence is often quenched by antiferromagnetic interactions between adjacent Mn2+ ions or electron‐phonon interactions, which lead to energy transfer to the defect states. Here, the modulation of photoluminescence by Mn–Mn magnetic ordering in a 2D layered hybrid perovskite (CH3NH3)2MnCl4 is reported. Specifically, antiferromagnetic ordering and spin flopping reduce the bright optical transitions from coupled Mn2+ ions, whereas ferromagnetic ordering enhances the transitions. This magnetic effect competes with electron‐phonon interactions and determines the temperature‐ and magnetic‐field‐dependent photoluminescence, especially at low temperatures. This study not only enriches the understanding of the fundamental magneto‐optical properties of Mn2+‐based perovskites but also provides new insights into the development of high‐performance lead‐free light‐emitting devices. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the imprecise (i.e., less mathematically precise) responses that 148 third- to fifth-grade Chinese students made on selected-response problems that were part of a spontaneous mathematical focusing task, the Quantitative Relations Test for Chinese Children (QRTC[superscript 2]). The purpose for this analysis was to ascertain whether the students' spontaneous responses represented random selections or followed discernible patterns. Those patterns were based on the specific attributes (i.e., featural, mathematical, numerical, and multiplicative) of the imprecise-response options for selected-response items on the QRTC[superscript 2]. Nonrandom selection patterns were identified by means of chi-square analysis and compared to patterns for the constructed-response portion of the QRTC[superscript 2]. For the chi-square analysis, the category involving imprecisions in both numerical and multiplicative attributes, and the category simultaneously involving numerical, multiplicative, and mathematical were significant. The analysis for the constructed problems also showed that children had difficulty describing the changes in the numerical and multiplicative attributes. Overall, the task of fully and accurately writing what they observed in the constructed-response problem on the QRTC[superscript 2] proved challenging for the children. Finally, imprecise response patterns the children exhibited on the QRTC[superscript 2] and their relational reasoning ability, as measured by the Test of Relational Reasoning-Junior (TORRjr) were significantly correlated. That significant correlation was attributable largely to the association between the children's analogical reasoning abilities and their QRTC[superscript 2] performance. We consider the theoretical, empirical, and practical implications of this work for mathematical learning and development.