Vertically-stacked W/W2C heterojunctions with high electrocatalytic capability for the hydrogen evolution reaction in a wide pH range.

The hydrogen evolution reaction (HER) in water splitting is among the foremost methods to produce clean and green hydrogen from renewable sources. The practical use of the HER technology is however hindered by the high price and/or the relatively low efficiency of the currently used catalysts. Herein, we report a heterostructured W/W2C electrocatalyst featuring vertically stacked interfaces and embedded in N-doped porous graphitic carbon (denoted as W/W2C@N-PGC) as a high-performance electrocatalyst for the HER in a wide pH range. The catalyst synthesis, accomplished through a straightforward one-pot method, is both facile and highly efficient, involving freeze-drying a suspension of the starting materials followed by pyrolyzing the obtained dry gel. Density functional theory calculations revealed the crucial role of the W/W2C heterojunction in promoting the two key steps of the HER, viz. HOH bond scission and H2 emission. Electrochemical data confirmed the excellent electrocatalytic capability of W/W2C@N-PGC toward the HER process in a wide pH range including alkaline, acidic, and neutral electrolytes. In 1.0 M KOH, we measured a low overpotential of 102 mV to drive a current density of 10 mA cm-2; a long-term stability (up to 24 h) was also realized. The data presented in this work highlight the importance of electrocatalysts with heterojunctions for the HER and the methodology presented in this work may be extended to other contemporary energy-related technologies such as CO2 reduction, oxygen evolution, and oxygen reduction reactions.

Nursing of forearm hematoma after transradial coronary intervention.

Background: Complications such as forearm hematoma after coronary intervention through the radial artery are a common complication. Material and methods: By observing, describing, and analyzing the pictures taken during clinical diagnosis and consultation, we summarize the prevention, treatment, and nursing of forearm hematoma after percutaneous coronary intervention, to provide reference for the nursing of patients with forearm hematoma. Results: We have innovatively summarized the risk classification of forearm hematoma and the three key time points for preventing hematoma. Conclusion: Complications such as forearm hematoma after coronary intervention through the radial artery are a common complication. We have innovatively summarized the risk classification of forearm hematoma and the three key time points for preventing hematoma, providing reference for the prevention and management of forearm hematoma in clinical practice. For patients undergoing transradial coronary intervention, the three key time points for preventing hematoma and symptomatic management based the risk classification of forearm hematoma are crucial.

Effects of low temperature air exposure and immersion on antioxidant, immune, intestinal flora and metabolome of Chinese mitten crab (Eriocheir sinensis).

The aim of this study was to investigate the effects of immersion on immune enzyme activity, haemolymph index, intestinal microbiome and metabolome of E. sinensis after low temperature air exposure. The results showed that low temperature air exposure induced stress response, which led to hepatopancreas injury and increased membrane permeability, but this situation was reversible and alleviated after immersion. In addition, after exposure to low temperature air, haemolymph metabolism-related substances such as glucose and total cholesterol were significantly different from the initial value (P < 0.05), and gradually returned to the initial level after immersion. The changes of intestinal flora and hepatopancreas metabolism caused by low temperature air exposure did not fully recover after immersion, and its negative effects did not completely disappear. The sequencing results showed that the species composition and diversity of intestinal microorganisms of Chinese mitten crabs were changed after low temperature air exposure and immersion treatment. The relative abundance of Bacteroidetes and Proteobacteria were increased, while the relative abundance of Firmicutes was decreased (P < 0.05). Metabolomics analysis showed that lysine levels increased significantly, taurocholic acid levels decreased significantly, and amino acid metabolism and lipid metabolism balance were disturbed in hepatopancreas of E. sinensis after exposure to low temperature air and immersion (P < 0.05). This study will provide new insights into the recovery mechanism of water immersion on Chinese mitten crabs after exposure to air.

Cost-effectiveness analysis of 11 pharmacotherapies for recurrent glioblastoma in the USA and China.

Background: Several studies have systematically assessed the efficacy and safety of progressive or recurrent glioblastoma multiforme (GBM). However, the discernible limitations of efficacy and the elevated costs of interventions instigate an investigation into the cost-effectiveness of these treatments. Objectives: This study aimed to evaluate cost-effectivenesses of 11 pharmacotherapeutic interventions for recurrent GBM from the perspective of healthcare payers in the United States (US) and China. Design: A model-based pharmacoeconomic evaluation. Methods: A partitioned survival model was employed to evaluate the cost-effectiveness of 11 distinct drug-based treatments. The clinical efficacy and safety data were obtained from a network meta-analysis, while the medical expenditure and health utility were primarily derived from published literature. One-way sensitivity analyses, scenario analyses, and probabilistic sensitivity analyses (PSA) were performed to scrutinize the impact of potential uncertainties to ensure the robustness of the model. The primary endpoint was the incremental cost-effectiveness ratio. Results: Among the therapeutic interventions evaluated, lomustine emerged as the cheapest option, with costs amounting to $78,998 in the United States and $30,231 in China, respectively. Regorafenib displayed the highest quality-adjusted life years at 0.475 in the United States and 0.465 in China. The one-way sensitivity analyses underscored that drug price was a key factor influencing cost-effectiveness. Both scenario and PSA consistently demonstrated that, considering the willingness-to-pay thresholds, lomustine was a cost-effective treatment with probability of more than 94%. Conclusion: In comparison to the alternative antitumor agents, lomustine was likely to be a cost-effective option for relapsed GBM patients from the perspective of healthcare payers in both the United States and China.

Rationality and implication of catheter-based adrenal ablation for bilateral primary aldosteronism.

Mineralocorticoid receptor antagonists (MRAs) for bilateral primary aldosteronism (PA) are the mainstay option recommended by guidelines, but poor compliance occurs due to numerous side effects. We aimed to examine whether catheter-based adrenal ablation could be an alternative treatment for bilateral PA.644 PA patients were included from a total of 6054 hypertensive patients. Adrenal CT scan and adrenal venous sampling (AVS) were both performed for PA subtype classification. Clinical and biochemical outcomes were assessed at 6 months after treatment according to the Primary Aldosteronism Surgical Outcome (PASO) criteria.93 patients with PA were recruited to be treated by adrenal ablation, including 25 bilateral PA and 68 unilateral PA according to AVS results. Office SBP and DBP significantly decreased from baseline levels, serum potassium levels increased and ARR significantly decreased (p < 0.01) in both the bilateral and unilateral groups. In the bilateral group, complete, partial and absent clinical success was achieved in 6 (24.0%), 11 (44.0%) and 8(32.0%) patients, respectively. In the unilateral group, complete, partial and absent clinical success was achieved in 12 (17.6%), 37 (54.4%), and 19 (27.9%) patients, respectively. The numbers of patients achieving complete, partial, and absent biochemical success were 15 (60.0%), 6 (24.0%), and 4 (16.0%), respectively, in the bilateral group versus 37 (54.4%), 9 (13.2%), and 22 (32.3%), respectively, in the unilateral group. In conclusion, we provide evidence for the beneficial outcomes of unilateral adrenal ablation for patients with bilateral PA. Our findings provide insight into an alternative option for patients with bilateral excess aldosterone.

Impact of competition on reimbursement decisions for cancer drugs in China: an observational study.

Background: Annual Chinese National negotiations for including innovative drugs in the National Reimbursement Drug List (NRDL) reveal an increasing number of new drugs with overlapping action mechanisms of action and similar indications. Yet, it is unclear if competition affects reimbursement decisions. Thus, we explored the impact of competition on reimbursement decisions for cancer drugs in China. Methods: We identified the cancer drugs involved in NRDL negotiations from 2017 to 2022 and focused on the initial reimbursement decision for eligible newly negotiated drugs. Drugs were classified as within-class competitors based on their equivalent biological mechanisms of action and approved indications, including identified and potential competitors. Other variables included drug type, clinical benefit and safety, monthly drug cost, and disease incidence rate. We employed traditional univariate and multivariate Firth's penalized logistic regression to assess the association between reimbursement decisions and variables at the indication and drug levels. Findings: Between 2017 and 2022, 102 cancer drugs corresponding to 141 indications were studied, and 66 drugs (64.7%) covering 95 indications (67.4%) were added to the NRDL. The proportion of reimbursements for indications with identified competition was significantly higher than that for indications without identified competition (84.6% vs 52.6%, p < 0.0001). However, the difference in reimbursement proportions between groups with and without potential competition was not statistically significant (66.7% vs 68.3%, p = 0.84). Firth's penalized logistic regression showed that identified competition was positively correlated with successful NRDL inclusion, whereas potential competition had no significant effect on negotiation outcomes. Improved overall survival or progression-free survival were positively associated with NRDL inclusion, whereas disease incidence negatively impacted reimbursement decisions. Interpretation: Improved clinical benefit and identified competition were positively correlated with NRDL inclusion. In China's value-based negotiation model, clinical benefits served as a crucial foundation of price negotiation for cancer drugs, and market competition helped these drugs enter the NRDL at more reasonable prices. This has important implications for reimbursement decisions and accessibility and affordability improvement for innovative drugs worldwide. Funding: National Natural Science Foundation of China (No. 72104151).

High-precision high-stability acousto-optic pulse picking driver with a direct digital synthesis technique.

A method for maintaining a fixed phase relationship between the driving signal of acousto-optic modulator (AOM) and the original mode-locked seed laser is proposed and realized, which stabilizes the amplitude of diffracted signal output from the AOM for subsequent amplification. A field-programmable gate array (FPGA), combined with external summing amplifiers, is used to directly synthesize high-timing-precision driving signals that are synchronized with the seed laser pulses, and the accuracy of signal timing control reaches 160 ps. Using this driver, the standard deviation of the diffracted signal output from the AOM is significantly decreased from 0.52% to 0.18%. This pulse-picking solution also includes a control system that can flexibly control the frequency, gating width, etc., of the driving signal, which makes it more convenient for subsequent laser amplification and makes it suitable for a variety of mode-locked lasers.

Fixed parameters in the population pharmacokinetic modeling of valproic acid might not be suitable: external validation in Chinese adults with epilepsy or after neurosurgery.

PURPOSE: This study aims to assess the predictive performance of published valproic acid (VPA) population pharmacokinetic (PPK) models using an external data set in Chinese adults with epilepsy or after neurosurgery. METHODS: A total of 384 concentrations from 290 Chinese adults with epilepsy or after neurosurgery were used for external validation. Data on published VPA PPK models were extracted from the literature. Prediction-based diagnostics (such as F20 and F30), simulation-based diagnostics, and Bayesian forecasting were used to evaluate the predictability of models. RESULTS: The results of prediction-based diagnostics of all models were unsatisfactory. Models B, F, and H showed the best prediction performance in simulation-based diagnostics and Bayesian forecasting, demonstrating superior precision and accuracy. Bayesian forecasting demonstrated significant improvements in the model predictability. CONCLUSION: The published PPK models showed extensive variation in predictive performance for extrapolation among Chinese adults with epilepsy or after neurosurgery patients. Fixed parameters of Vd and Ka in the PPK modeling of VPA might be the reason for the unsatisfied predictive performance. Bayesian forecasting significantly improved model predictability and may help to individualize VPA dosing.

Integrated analyses of single-cell transcriptome and Mendelian randomization reveal the protective role of FCRL3 in multiple sclerosis.

Background: Multiple sclerosis (MS) represents a multifaceted autoimmune ailment, prompting the development and widespread utilization of numerous therapeutic interventions. However, extant medications for MS have proven inadequate in mitigating relapses and halting disease progression. Innovative drug targets for preventing multiple sclerosis are still required. The objective of this study is to discover novel therapeutic targets for MS by integrating single-cell transcriptomics and Mendelian randomization analysis. Methods: The study integrated MS genome-wide association study (GWAS) data, single-cell transcriptomics (scRNA-seq), expression quantitative trait loci (eQTL), and protein quantitative trait loci (pQTL) data for analysis and utilized two-sample Mendelian randomization study to comprehend the causal relationship between proteins and MS. Sequential analyses involving colocalization and Phenome-wide association studies (PheWAS) were conducted to validate the causal role of candidate genes. Results: Following stringent quality control preprocessing of scRNA-seq data, 1,123 expression changes across seven peripheral cell types were identified. Among the seven most prevalent cell types, 97 genes exhibiting at least one eQTL were discerned. Examination of MR associations between 28 proteins with available index pQTL signals and the risk of MS outcomes was conducted. Co-localization analyses and PheWAS indicated that FCRL3 may exert influence on MS. Conclusion: The integration of scRNA-seq and MR analysis facilitated the identification of potential therapeutic targets for MS. Notably, FCRL3, implicated in immune function, emerged as a significant drug target in the deCODE databases. This research underscores the importance of FCRL3 in MS therapy and advocates for further investigation and clinical trials targeting FCRL3.

Development of two novel on-site detection visualization methods for murine hepatitis virus based on the multienzyme isothermal rapid amplification.

Murine hepatitis virus (MHV) infection is one of the most prevalent types of mice infection in laboratory. MHV could cause death in mice and even interfere with the results in animal experiments. Herein, we developed two isothermal approaches based on the Multienzyme Isothermal Rapid Amplification (MIRA), for rapid detection of MHV in conserved M gene. We designed and screened several pairs of primers and probes and the isothermal fluorescence detector was applied for the exonuclease Ⅲ reverse transcription MIRA (exo-RT-MIRA) assay. To further simplify the workflow, the portable fluorescence visualization instrument, also as a palm-sized handheld system, was used for the naked-eye exo-RT-MIRA assay. The amplification temperature and time were optimized. The assay could be processed well at 42 °C 20 min for the exo-RT-MIRA and the naked-eye exo-RT-MIRA assay. The limit of detection (LoD) of the exo-RT-MIRA assay was 43.4 copies/µL. The LoD of the naked-eye exo-RT-MIRA assay was 68.2 copies/µL. No nonspecific amplifications were observed in the two assays. A total of 107 specimens were examined by qPCR and two assays developed. The experimental results statistical analysis demonstrated that the exo-RT-MIRA assay with the qPCR yielded sufficient agreement with a kappa value of 1.000 (p < 0.0001). The results also exhibited a good agreement (kappa value, 0.961) (p < 0.0001) between the naked-eye exo-RT-MIRA assay and the qPCR assay. In our study, the exo-RT-MIRA assay and the naked-eye exo-RT-MIRA assay presented the possibility of new methods in MHV point-of-testing diagnosis.

Effects of dietary ginger (Zingiber officinale) polysaccharide on the growth, antioxidant, immunity response, intestinal microbiota, and disease resistance to Aeromonas hydrophila in crucian carp (Carassius auratus).

Ginger polysaccharides (GP) promote growth and development in fish. However, the effects of GP on crucian carp remain unclear. The present study investigated the effects of GP on the growth performance, immunity, intestinal microbiota, and disease resistance in crucian carp. Four treatment groups were established with different concentrations of GP (0.1 %, 0.2 %, 0.4 %, and 0.8 %). GP was not added as the control group, and the feeding period lasted for 56 d, followed by a 96-h anti-infection treatment using Aeromonas hydrophila. The results showed that dietary GP significantly improved growth performance, especially in the 0.4 % GP group. Furthermore, GP administration notably increased serum lysozyme (LMZ) activity, digestive enzyme performance, and antioxidant capacity of crucian carp. Moreover, dietary inclusion of GP up-regulated the expression of tumour necrosis factor-α (TNF-α), interleukin-8 (IL-8), interferon-γ (IFN-γ), and nuclear factor kappa-B (NF-κB) genes while down-regulating IL-10 and transforming growth factor-ß (TGF-ß) gene expressions, thus promoting liver health in crucian carp. Additionally, incorporating GP into the diet regulated both the diversity and composition of the intestinal microbiota in crucian carp, explicitly enhancing the relative abundance of beneficial bacteria, such as Fusobacteriota and Firmicutes. Therefore, GP reduces the mortality of crucian carp infected with A. hydrophila. In conclusion, this study provides novel insights into the application of dietary GP in cultured fish and evaluates the value of traditional Chinese medicinal polysaccharides against pathogenic bacteria.

Causal impact of statins on susceptibility to osteoarthritis: insights from a two-sample Mendelian randomization analysis.

BACKGROUND: Osteoarthritis is a widely prevalent cause of pain and disability among older adults. It is an incurable condition, and most treatments are aimed at alleviating symptoms. AIM: This study aimed to investigate the impact of statins on osteoarthritis by using a two-sample Mendelian randomization approach, using genetic variants associated with statin use as instrumental variables. METHOD: Information on single nucleotide polymorphisms associated with statin medication was obtained from the FinnGen study, and data on osteoarthritis were sourced from the UK Biobank. The inverse variance weighted method was used as the primary analytical approach for the Mendelian randomization analysis. Sensitivity analyses were conducted to evaluate horizontal pleiotropy and heterogeneity. To examine the genetic relationship between statins and osteoarthritis, linkage disequilibrium score regression-based estimates were used. RESULTS: Mendelian randomization analysis indicated a positive effect of statin use on the treatment of osteoarthritis (odds ratio 0.951, 95% confidence interval 0.914-0.99, p < 0.05). This conclusion was supported by various Mendelian randomization methods. Sensitivity analyses revealed no significant directional pleiotropy or influential single nucleotide polymorphisms that could compromise the overall causal inference. Linkage disequilibrium score regression-based estimates suggested a modest genetic correlation between statin use and osteoarthritis (Rg = 0.098, Se = 0.034, p < 0.05), thus reinforcing the robustness of the Mendelian randomization analysis. CONCLUSION: Statins reduce the risk of osteoarthritis, aligning with the results of observational studies. Further research is essential to validate these results and explore the underlying mechanisms in detail.

Reappraisal and refined diagnosis of ultrasonography and histological findings for hydatidiform moles: a multicentre retrospective study of 821 patients.

AIMS: Specific identification of a hydatidiform mole (HM) and subclassification of a complete hydatidiform mole (CHM) or partial hydatidiform mole (PHM) are critical. This study aimed to reappraise the diagnostic performance of ultrasonography and histology with a refined diagnosis. METHODS: This was a retrospective, multicentre cohort study of 821 patients with histologically suspected HM specimens. Refined diagnostic algorithms with p57 immunohistochemistry and short tandem repeat (STR) genotyping were performed and used as the true standard for assessing the diagnostic performance of the original ultrasonography and morphology methods. The diagnostic performance was calculated using accuracy, agreement rate, sensitivity and the positive predictive value (PPV) compared with refined diagnostic results. RESULTS: Of the 821 histologically suspected HM cases included, 788 (95.98%) were successfully reclassified into 448 CHMs, 213 PHMs and 127 non-molar (NM) abortuses. Ultrasonography showed an overall accuracy of 44.38%, with a sensitivity of 44.33% for CHM and 37.5% for PHM. The overall classification accuracy of the original morphological diagnosis was 65.97%. After exclusion of the initially untyped HMs, the overall agreement rate was 59.11% (κ=0.364, p<0.0001) between the original and refined diagnoses, with a sensitivity of 40.09% and PPV of 96.05% for diagnosing CHMs and a sensitivity of 84.98% and a PPV of 45.59% for diagnosing PHMs. The interinstitutional variability of morphology in diagnosing HMs was significant among the 15 centres (range, 8.33%-100.00%, p<0.0001). CONCLUSION: The current diagnosis of HM based solely on ultrasound or morphology remains problematic, and ancillary techniques, particularly p57 immunohistochemistry and DNA genotyping, should be integrated into routine practice as much as possible.

Effect of Filling Material Properties on 1-3 Piezoelectric Composite Performance.

The 1-3 piezoelectric composite is the key component of the acoustic transducer, which is widely used in detection, due to the high energy conversion efficiency, cheap raw material, and low aging. To reveal the influence of epoxy mixture, used to connect the piezoelectric column, on the composite performance, a 1-3 piezoelectric composite model was built. The effects of mixture properties on the impedance curves, vibration mode, and deformation displacement of the composite were determined. Six 1-3 piezoelectric composites with different filling mixture properties, by changing the glass microspheres' mass ratio in the epoxy, were prepared and measured to validate the model. The results showed that with the increase in the proportion of the glass microsphere in the epoxy mixture, the vibration coupling of the piezoelectric composites was gradually eliminated. The acoustic impedance was reduced by 12%. The electromechanical coupling coefficient and effective electromechanical coupling coefficient were increased by 5.4% and 8.3%, respectively. The density and Young's modulus decrease in filling mixture can significantly improve piezoelectric composite performance.

SpRY-mediated screens facilitate functional dissection of non-coding sequences at single-base resolution.

CRISPR mutagenesis screens conducted with SpCas9 and other nucleases have identified certain cis-regulatory elements and genetic variants but at a limited resolution due to the absence of protospacer adjacent motif (PAM) sequences. Here, leveraging the broad targeting scope of the near-PAMless SpRY variant, we have demonstrated that saturated SpRY mutagenesis and base editing screens can faithfully identify functional regulatory elements and essential genetic variants for target gene expression at single-base resolution. We further extended this methodology to investigate a genome-wide association study (GWAS) locus at 10q22.1 associated with a red blood cell trait, where we identified potential enhancers regulating HK1 gene expression, despite not all of these enhancers exhibiting typical chromatin signatures. More importantly, our saturated base editing screens pinpoint multiple causal variants within this locus that would otherwise be missed by Bayesian statistical fine-mapping. Our approach is generally applicable to functional interrogation of all non-coding genomic elements while complementing other high-coverage CRISPR screens.

Changes in thyroid hormones predict weight regain in patients with obesity who undergo metabolic surgery.

AIM: To investigate the relationship between thyroid function and weight regain in patients with obesity after metabolic surgery. METHODS: This retrospective study enrolled 162 patients who underwent metabolic surgery. Correlations between decreases in thyroid hormone levels and changes in weight, waist circumference (WC) and the Chinese visceral adiposity index (CVAI) were assessed. Binary logistic regression and receiver operating characteristic (ROC) curves were used to identify predictors and clinically useful cut-off values, respectively. RESULTS: The levels of thyroid-stimulating hormone (TSH) and free triiodothyronine (FT3) decreased markedly at 1 year after surgery, as did weight, body mass index (BMI), triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, WC and CVAI. Decreases in TSH and FT3 after metabolic surgery were associated with changes in weight, BMI and CVAI. Binary logistic regression and ROC curve analyses confirmed that decreases in TSH can predict good weight loss after metabolic surgery to some extent. Finally, binary logistic regression and ROC curve analyses confirmed that changes in TSH can predict weight regain after metabolic surgery. CONCLUSIONS: Changes in TSH and FT3 after metabolic surgery were correlated with changes in weight and CVAI. Changes in thyroid hormones can predict weight regain in patients with obesity who underwent metabolic surgery.

Genetic influence of meningioma on cisplatin resistance: a Mendelian randomization analysis.

BACKGROUND: Although various aspects of cisplatin resistance have been studied, the impact of genetic variations still needs to be explored. AIM: This study aimed to investigate the impact of cisplatin on meningiomas using a two-sample Mendelian randomization (MR) approach, employing genetic variants associated with cisplatin use as instrumental variables. METHOD: We conducted a two-sample MR analysis using genome-wide association study (GWAS) data. Instrumental variables were derived from single-nucleotide polymorphisms (SNPs) associated with meningioma to estimate the causal relationship with cisplatin resistance. Sensitivity analyses were performed to confirm the findings. RESULTS: Genetic predisposition to meningioma significantly increased the risk of cisplatin resistance (odds ratio (OR): 1.63; 95% confidence interval (CI) 1.44-1.85, P < 0.05). Sensitivity analyses supported the causal link. CONCLUSION: This MR study suggests that genetic predisposition to meningioma increases susceptibility to cisplatin resistance. Further research is needed to uncover the mechanisms behind these causal effects.

High-efficiency single-frequency DBR fiber laser at 1091 nm utilizing a Yb:YAG crystal-derived silica fiber.

A single-frequency distributed Bragg Reflector (DBR) fiber laser operating at 1091 nm was demonstrated by using a Yb:YAG crystal-derived silica fiber (YDSF). The YDSF was prepared via the molten core (MC) method, with a Yb2O3 doping concentration of 5.60 wt.% in the core, resulting in a gain coefficient of 1.45 dB/cm at 1091 nm. Employing 0.8 cm of the YDSF, we attained a single-frequency laser with a maximum output power of 145 mW and a slope efficiency of 31.8%. The laser exhibited an optical signal-to-noise ratio (OSNR) exceeding 71 dB, a linewidth of ∼34 kHz, and a stabilized relative intensity noise (RIN) at -132 dB/Hz for frequencies over 4.5 MHz. The fiber laser could serve as an outstanding seed source for high-power, narrow-linewidth fiber amplifiers operating at 1091 nm.

OsSRF8 interacts with OsINP1 and OsDAF1 to regulate pollen aperture formation in rice.

In higher plants, mature male gametophytes have distinct apertures. After pollination, pollen grains germinate, and a pollen tube grows from the aperture to deliver sperm cells to the embryo sac, completing fertilization. In rice, the pollen aperture has a single-pore structure with a collar-like annulus and a plug-like operculum. A crucial step in aperture development is the formation of aperture plasma membrane protrusion (APMP) at the distal polar region of the microspore during the late tetrad stage. Previous studies identified OsINP1 and OsDAF1 as essential regulators of APMP and pollen aperture formation in rice, but their precise molecular mechanisms remain unclear. We demonstrate that the Poaceae-specific OsSRF8 gene, encoding a STRUBBELIG-receptor family 8 protein, is essential for pollen aperture formation in Oryza sativa. Mutants lacking functional OsSRF8 exhibit defects in APMP and pollen aperture formation, like loss-of-function OsINP1 mutants. OsSRF8 is specifically expressed during early anther development and initially diffusely distributed in the microsporocytes. At the tetrad stage, OsSRF8 is recruited by OsINP1 to the pre-aperture region through direct protein-protein interaction, promoting APMP formation. The OsSRF8-OsINP1 complex then recruits OsDAF1 to the APMP site to co-regulate annulus formation. Our findings provide insights into the mechanisms controlling pollen aperture formation in cereal species.

Stacking and ridge regression-based spectral ensemble preprocessing method and its application in near-infrared spectral analysis.

Spectral preprocessing techniques can, to a certain extent, eliminate irrelevant information, such as current noise and stray light from spectral data, thereby enhancing the performance of prediction models. However, current preprocessing techniques mostly attempt to find the best single preprocessing method or their combination, overlooking the complementary information among different preprocessing methods. These preprocessing techniques fail to maximize the utilization of useful information in spectral data and restrict the performance of prediction models. This study proposed a spectral ensemble preprocessing method based on the rapidly developing ensemble learning methods in recent years and the ridge regression (RR) model, named stacking preprocessing ridge regression (SPRR), to address the aforementioned issues. Different from conventional ensemble learning methods, the proposed SPRR method applied multiple different preprocessing techniques to the original spectral data, generating multiple preprocessed datasets. These datasets were then individually inputted into RR base models for training. Ultimately, RR still served as the meta-model, integrating the output results of each RR base model through stacking. This approach not only produced diversity in base models but also achieved higher accuracy and lower computational complexity by using a single type of base model. On the apple spectral dataset collected by our team, correlation analysis showed significant complementary information among the data produced by different preprocessing techniques. This provided robust theoretical support for the proposed SPRR method. By introducing the currently popular averaging ensemble preprocessing method in a comparative experiment, the results of applying the proposed SPRR method to six datasets (apple, meat, wheat, olive oil, tablet, and corn) demonstrated that compared to the single preprocessing method and averaging ensemble preprocessing method, SPRR yielded the best accuracy and reliability for all six datasets. Furthermore, under the same conditions of the training and test datasets, the proposed SPRR method demonstrated better performance than the four commonly used ensemble preprocessing methods.