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In practical engineering applications, factors like dust adhesion and environmental changes can cause photovoltaic arrays to exhibit multiple peaks in output power. An optimization algorithm with global optimization capability is needed to track its maximum power. In this regard, this paper proposes an improved marine predator algorithm (IMPA) to extract the maximum power point of photovoltaic system under complex solar irradiation conditions. To overcome the issues in the traditional marine predator algorithm (MPA), the opposition-based learning(OBL) strategy is introduced in IMPA, and the sine cosine algorithm (SCA) is integrated into the iteration stage to enhance the search ability of the algorithm. Furthermore, the low-order converter in the traditional MPPT control system is replaced by the Zeta converter, which increases the operating voltage range. Ultimately, simulation results demonstrate that the MPPT based on IMPA has higher tracking efficiency and shorter response time.The experimental results also indicate the practical feasibility of this method, as well as its high level of stability and robustness.

In response to the challenges presented by the unreliable identity of the master node, high communication overhead, and limited network support size within the Practical Byzantine Fault-Tolerant (PBFT) algorithm for consortium chains, we propose an improved PBFT algorithm based on XGBoost grouping called XG-PBFT in this paper. XG-PBFT constructs a dataset by training important parameters that affect node performance, which are used as classification indexes for nodes. The XGBoost algorithm then is employed to train the dataset, and nodes joining the system will be grouped according to the trained grouping model. Among them, the nodes with higher parameter indexes will be assigned to the consensus group to participate in the consensus, and the rest of the nodes will be assigned to the general group to receive the consensus results. In order to reduce the resource waste of the system, XG-PBFT optimizes the consensus protocol for the problem of high complexity of PBFT communication. Finally, we evaluate the performance of XG-PBFT. The experimental results show that XG-PBFT can significantly improve the performance of throughput, consensus delay and communication complexity compared to the original PBFT algorithm, and the performance enhancement is significant compared to other algorithms in the case of a larger number of nodes. The results demonstrate that the XG-PBFT algorithm is more suitable for large-scale consortium chains.

Background This study aimed to compare the clinical efficacy of anterior cervical discectomy and fusion (ACDF) with self-lock cage through mini-incision, ACDF with cage and plate, and posterior laminoplasty (LAMP) for long-level cervical spondylosis without severe ossification of posterior longitudinal ligament. Method From January 2018 to January 2021, patients diagnosed with 3–4 segments (C3-7) cervical spondylotic radiculopathy, cervical spondylotic myelopathy, or mixed cervical spondylosis underwent surgical treatment. The procedures included ACDF with self-lock cage through mini-incision (48 cases) (group A), ACDF with cage and plate (37 cases) (group B), and LAMP (40 cases) (group C). Surgical parameters such as operative time, blood loss, incision length, and hospital stay were documented. Additionally, measurements were taken for intervertebral height, functional segment height, cervical lordosis, cervical hyperextension and hyperflexion range-of-motion (ROM), and ROM in all directions of the cervical spine before and after surgery. The therapeutic outcomes of both groups were evaluated, and any postoperative complications were meticulously recorded. Results There was no significant difference in gender, age, JOA, VAS score of upper limb, NDI score, preoperative cervical intervertebral height, functional segment height, lordosis angle, cervical ROM, hyperextension and hyperflexion ROM was observed among three groups. The patients in group A and group B had less bleeding, shorter incision, and fewer hospitalization days than group C ( P  < 0.05). The patients in group A had a shorter incision than those in group B ( P  < 0.05). Group A showed shortest operation time(A < B < C)( P  < 0.05). There was no significant difference in JOA, VAS score of upper limb, NDI score after surgery among three groups. The restoration of postoperative intervertebral height, functional segment height, and cervical lordosis angle of group A and group B were significantly more than those of group C ( P  < 0.05). There was no significant difference between preoperative and postoperative ROM in all directions of cervical spine in three groups. Conclusions All three surgical techniques—self-locking cage ACDF, cage-and-plate ACDF, and LAMP—are effective options for treating long-level cervical spondylosis without severe OPLL. Among them, the self-locking cage technique offers distinct advantages, including smaller incisions, less surgical trauma, a lower risk of postoperative dysphagia, and a high fusion rate even in multilevel procedures.

AbstractObjectiveTo determine, in critically ill patients, the relative impact of proton pump inhibitors (PPIs), histamine-2 receptor antagonists (H2RAs), sucralfate, or no gastrointestinal bleeding prophylaxis (or stress ulcer prophylaxis) on outcomes important to patients.DesignSystematic review and network meta-analysis.Data sourcesMedline, PubMed, Embase, Cochrane Central Register of Controlled Trials, trial registers, and grey literature up to March 2019.Eligibility criteria for selecting studies and methodsWe included randomised controlled trials that compared gastrointestinal bleeding prophylaxis with PPIs, H2RAs, or sucralfate versus one another or placebo or no prophylaxis in adult critically ill patients. Two reviewers independently screened studies for eligibility, extracted data, and assessed risk of bias. A parallel guideline committee (BMJ Rapid Recommendation) provided critical oversight of the systematic review, including identifying outcomes important to patients. We performed random-effects pairwise and network meta-analyses and used GRADE to assess certainty of evidence for each outcome. When results differed between low risk and high risk of bias studies, we used the former as best estimates.ResultsSeventy two trials including 12 660 patients proved eligible. For patients at highest risk (>8%) or high risk (4-8%) of bleeding, both PPIs and H2RAs probably reduce clinically important gastrointestinal bleeding compared with placebo or no prophylaxis (odds ratio for PPIs 0.61 (95% confidence interval 0.42 to 0.89), 3.3% fewer for highest risk and 2.3% fewer for high risk patients, moderate certainty; odds ratio for H2RAs 0.46 (0.27 to 0.79), 4.6% fewer for highest risk and 3.1% fewer for high risk patients, moderate certainty). Both may increase the risk of pneumonia compared with no prophylaxis (odds ratio for PPIs 1.39 (0.98 to 2.10), 5.0% more, low certainty; odds ratio for H2RAs 1.26 (0.89 to 1.85), 3.4% more, low certainty). It is likely that neither affect mortality (PPIs 1.06 (0.90 to 1.28), 1.3% more, moderate certainty; H2RAs 0.96 (0.79 to 1.19), 0.9% fewer, moderate certainty). Otherwise, results provided no support for any affect on mortality, Clostridium difficile infection, length of intensive care stay, length of hospital stay, or duration of mechanical ventilation (varying certainty of evidence).ConclusionsFor higher risk critically ill patients, PPIs and H2RAs likely result in important reductions in gastrointestinal bleeding compared with no prophylaxis; for patients at low risk, the reduction in bleeding may be unimportant. Both PPIs and H2RAs may result in important increases in pneumonia. Variable quality evidence suggested no important effects of interventions on mortality or other in-hospital morbidity outcomes.Systematic review registrationPROSPERO CRD42019126656.

In the evolving field of neurophysiological research, visual light flicker stimulation is recognized as a promising non-invasive intervention for cognitive enhancement, particularly in sleep-deprived conditions. This study explored the effects of specific flicker frequencies (40 Hz and 20-30 Hz random flicker) on alertness recovery in sleep-deprived rats. We employed a multidisciplinary approach that included behavioral assessments with the Y-maze, in vivo electrophysiological recordings, and molecular analyses such as c-FOS immunohistochemistry and hormone level measurements. Both 40 Hz and 20-30 Hz flicker significantly enhanced behavioral performance in the Y-maze test, suggesting an improvement in alertness. Neurophysiological data indicated activation of neural circuits in key brain areas like the thalamus and hippocampus. Additionally, flicker exposure normalized cortisol and serotonin levels, essential for stress response and mood regulation. Notably, increased c-FOS expression in brain regions related to alertness and cognitive functions suggested heightened neural activity. These findings underscore the potential of light flicker stimulation not only to mitigate the effects of sleep deprivation but also to enhance cognitive functions. The results pave the way for future translational research into light-based therapies in human subjects, with possible implications for occupational health and cognitive ergonomics.

Vaccination is still the most promising strategy for combating influenza virus pandemics. However, the highly variable characteristics of influenza virus make it difficult to develop antibody-based universal vaccines, until now. Lung tissue-resident memory T cells (T RM ), which actively survey tissues for signs of infection and react rapidly to eliminate infected cells without the need for a systemic immune reaction, have recently drawn increasing attention towards the development of a universal influenza vaccine. We previously designed a sequential immunization strategy based on orally administered Salmonella vectored vaccine candidates. To further improve our vaccine design, in this study, we used two different dendritic cell (DC)-targeting strategies, including a single chain variable fragment (scFv) targeting the surface marker DC-CD11c and DC targeting peptide 3 (DCpep3). Oral immunization with Salmonella harboring plasmid pYL230 (S230), which displayed scFv-CD11c on the bacterial surface, induced dramatic production of spleen effector memory T cells (T EM ). On the other hand, intranasal boost immunization using purified DCpep3-decorated 3M2e-ferritin nanoparticles in mice orally immunized twice with S230 (S230inDC) significantly stimulated the differentiation of lung CD11b + DCs, increased intracellular IL-17 production in lung CD4 + T cells and elevated chemokine production in lung sections, such as CXCL13 and CXCL15, as determined by RNAseq and qRT‒PCR assays, resulting in significantly increased percentages of lung T RM s, which could provide efficient protection against influenza virus challenge. The dual DC targeting strategy, together with the sequential immunization approach described in this study, provides us with a novel “prime and pull” strategy for addressing the production of protective T RM cells in vaccine design.

The cuprate high-temperature superconductors exhibit many unexplained electronic phases, but it was often thought that the superconductivity at sufficiently high doping is governed by conventional mean-field Bardeen-Cooper-Schrieffer (BCS) theory[1]. However, recent measurements show that the number of paired electrons (the superfluid density) vanishes when the transition temperature Tc goes to zero[2], in contradiction to expectation from BCS theory. The origin of this anomalous vanishing is unknown. Our scanning tunneling spectroscopy measurements in the overdoped regime of the (Pb,Bi)2Sr2CuO6+{\\delta} high-temperature superconductor show that it is due to the emergence of puddled superconductivity, featuring nanoscale superconducting islands in a metallic matrix[3,4]. Our measurements further reveal that this puddling is driven by gap filling, while the gap itself persists beyond the breakdown of superconductivity. The important implication is that it is not a diminishing pairing interaction that causes the breakdown of superconductivity. Unexpectedly, the measured gap-to-filling correlation also reveals that pair-breaking by disorder does not play a dominant role and that the mechanism of superconductivity in overdoped cuprate superconductors is qualitatively different from conventional mean-field theory.