Female semiochemicals stimulate male courtship but dampen female sexual receptivity.

Chemical communication plays a vital role in mate attraction and discrimination among many insect species. Here, we document a unique example of semiochemical parsimony, where four chemicals act as both aphrodisiacs and anti-aphrodisiacs in different contexts in Bactrocera dorsalis. Specifically, we identified four female-specific semiochemicals, ethyl laurate, ethyl myristate, ethyl cis-9-hexadecenoate, and ethyl palmitate, which serve as aphrodisiacs to attract male flies and arouse male courtship. Interestingly, these semiochemicals, when sexually transferred to males during mating, can function as anti-aphrodisiacs, inhibiting the receptivity of subsequent female mates. We further showed that the expression of elongase11, a key enzyme involved in the biosynthesis of these semiochemicals, is under the control of doublesex, facilitating the exclusive biosynthesis of these four semiochemicals in females and guaranteeing effective chemical communication. The dual roles of these semiochemicals not only ensure the attractiveness of mature females but also provide a simple yet reliable mechanism for female mate discrimination. These findings provide insights into chemical communication in B. dorsalis and add elements for the design of pest control programs.

Role of macrophages in regression of myocardial fibrosis following alleviation of left ventricular pressure overload.

Sustained hemodynamic pressure overload (PO) produced by murine transverse aortic constriction (TAC) causes myocardial fibrosis; removal of TAC (unTAC) returns left ventricle (LV) hemodynamic load to normal and results in significant, but incomplete regression of myocardial fibrosis. However, the cellular mechanisms that result in these outcomes have not been defined. The objective was to determine temporal changes in myocardial macrophage phenotype in TAC and unTAC and determine whether macrophage depletion alters collagen degradation after unTAC. Myocardial macrophage abundance and phenotype were assessed by immunohistochemistry, flow cytometry, and gene expression by RT-PCR in control (non-TAC), 2 wk, 4 wk TAC, and 2 wk, 4 wk, and 6 wk unTAC. Myocardial cytokine profiles and collagen-degrading enzymes were determined by immunoassay and immunoblots. Initial collagen degradation was detected with collagen-hybridizing peptide (CHP). At unTAC, macrophages were depleted with clodronate liposomes, and endpoints were measured at 2 wk unTAC. Macrophage number had a defined temporal pattern: increased in 2 wk and 4 wk TAC, followed by increases at 2 wk unTAC (over 4 wk TAC) that then decreased at 4 wk and 6 wk unTAC. At 2 wk unTAC, macrophage area was significantly increased and was regionally associated with CHP reactivity. Cytokine profiles in unTAC reflected a proinflammatory milieu versus the TAC-induced profibrotic milieu. Single-cell sequencing analysis of 2 wk TAC versus 2 and 6 wk unTAC revealed distinct macrophage gene expression profiles at each time point demonstrating unique macrophage populations in unTAC versus TAC myocardium. Clodronate liposome depletion at unTAC reduced CHP reactivity and decreased cathepsin K and proMMP2. We conclude that temporal changes in number and phenotype of macrophages play a critical role in both TAC-induced development and unTAC-mediated partial, but incomplete, regression of myocardial fibrosis.NEW & NOTEWORTHY Our novel findings highlight the dynamic changes in myocardial macrophage populations that occur in response to PO and after alleviation of PO. Our data demonstrated, for the first time, a potential benefit of macrophages in contributing to collagen degradation and the partial regression of interstitial fibrosis following normalization of hemodynamic load.

Alterations of the bile microbiome is associated with progression-free survival in pancreatic ductal adenocarcinoma patients.

BACKGROUND: Patients with pancreatic ductal adenocarcinoma (PDAC) display an altered oral, gastrointestinal, and intra-pancreatic microbiome compared to healthy individuals. However, knowledge regarding the bile microbiome and its potential impact on progression-free survival in PDACs remains limited. METHODS: Patients with PDAC (n = 45), including 20 matched pairs before and after surgery, and benign controls (n = 16) were included prospectively. The characteristics of the microbiomes of the total 81 bile were revealed by 16  S-rRNA gene sequencing. PDAC patients were divided into distinct groups based on tumor marker levels, disease staging, before and after surgery, as well as progression free survival (PFS) for further analysis. Disease diagnostic model was formulated utilizing the random forest algorithm. RESULTS: PDAC patients harbor a unique and diverse bile microbiome (PCoA, weighted Unifrac, p = 0.038), and the increasing microbial diversity is correlated with dysbiosis according to key microbes and microbial functions. Aliihoeflea emerged as the genus displaying the most significant alteration among two groups (p < 0.01). Significant differences were found in beta diversity of the bile microbiome between long-term PFS and short-term PFS groups (PCoA, weighted Unifrac, p = 0.005). Bacillota and Actinomycetota were identified as altered phylum between two groups associated with progression-free survival in all PDAC patients. Additionally, we identified three biomarkers as the most suitable set for the random forest model, which indicated a significantly elevated likelihood of disease occurrence in the PDAC group (p < 0.0001). The area under the receiver operating characteristic (ROC) curve reached 80.8% with a 95% confidence interval ranging from 55.0 to 100%. Due to the scarcity of bile samples, we were unable to conduct further external verification. CONCLUSION: PDAC is characterized by an altered microbiome of bile ducts. Biliary dysbiosis is linked with progression-free survival in all PDACs. This study revealed the alteration of the bile microbiome in PDACs and successfully developed a diagnostic model for PDAC.

Insight into the Dynamic Nature of the Pt-CeO2 Interface in Dry Reforming of Methane.

Single-atom catalysts (SACs) are attractive in one-carbon (C1) chemistry because of their high atom efficiency. However, it is a great challenge for understanding the dynamic roles of SACs under operating conditions. Here, isolated Pt atoms trapped on defective CeO2 surface are investigated by experiments, especially operando techniques, which offers basic understanding of the nature and dynamic evolution of the Pt-CeO2 interface in dry reforming of methane (DRM). The Pt-Olattice configuration is highly active for CH4 dissociation at the expense of the Olattice atoms, which in turn promotes the H-assisted dissociation of CO2. The transformation of Pt atoms between positive and metallic states is driven by the DRM reaction, which is essential for rendering highly efficient catalysis. The dynamic evolution of Pt atoms favors to eliminate the reactive intermediates, such as carbonates and formates. The dynamic nature of the Pt-CeO2 interface in the DRM reaction shows a similar picture to the Yin and Yang transformation in ancient Chinese Tai Ji wisdom.

Ginsenoside Rb3 alleviates the formation of osteoclasts induced by periodontal ligament fibroblasts in the periodontitis microenvironment through the STAT3 pathway.

This study explores the potential role and mechanism of Ginsenoside Rb3 (Rb3) in modulating osteoclastogenesis induced by human periodontal ligament fibroblasts (hPLFs) within the periodontitis microenvironment. We investigated the anti-inflammatory effects of Rb3 on hPLFs stimulated with Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) utilizing quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay techniques. Moreover, the functional role of Rb3 in hPLFs-induced osteoclast formation was assessed by treating human bone marrow-derived macrophages (hBMMs) with conditioned medium from hPLFs, followed by analyses through qPCR, western blot analysis, and staining for tartrate-resistant acid phosphatase (TRAP) and phalloidin. The impact of Rb3 on the activation of the STAT3 signaling pathway was determined via western blot analysis. Results indicated that Rb3 treatment significantly suppressed the upregulation of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, MCP-1, and IL-18) at both gene and protein levels in hPLFs induced by P.g-LPS. Furthermore, conditioned medium from Rb3 plus P.g-LPS treated hPLFs notably decreased the number of TRAP-positive cells, actin ring formations, and the expression of osteoclast marker genes (including CTSK, NFATC1, and ACP5). Rb3 also inhibited the P.g-LPS-induced activation of the STAT3 pathway, with the activation of STAT3 partially reversing the effects of Rb3 on inflammation and osteoclast differentiation. Collectively, Rb3 ameliorates inflammation in P.g-LPS-stimulated hPLFs and reduces hPLFs-induced osteoclastogenesis by inhibiting the STAT3 signaling pathway, suggesting its potential as a therapeutic agent for periodontitis.

Fischer-Tropsch Synthesis of C4-C5 Isoparaffins via CoxMn1-xO Nanocomposites with Suppressed CO2.

The synthesis of a specific product via the Fischer-Tropsch synthesis remains challenging due to the uncontrollable coupling of CHx on active sites. Isoparaffins, essential high-quality petroleum additives for improving octane numbers, are primarily derived from petroleum or natural gas. With petroleum reserves dwindling and the associated low selectivity, the direct conversion of syngas to isoparaffins has emerged as a promising alternative. This study presents a tandem catalyst comprising CoxMn1-xO and zeolites for catalyzing the direct conversion of syngas to C4-C5 isoparaffins. The relay catalyst exhibited an impressive selectivity of 55.6% toward the desired products while maintaining a low CO2 selectivity of approximately 20%. Notably, the selectivity of isobutane reached 43.5%, exceeding predictions based on the Anderson-Schulz-Flory distribution. Syngas undergoes conversion into olefins on CoxMn1-xO nanocomposites, diffuses into microporous zeolites, and interacts with Brønsted acids to produce isoparaffins. The stability of the relay catalyst relied significantly on the pore characteristics and acidic density of the zeolites.

Fabrication of fluorescence probe based on molecularly imprinted polymers on red emissive biomass-derived carbon dots coupled with smartphone readout for tyramine determination in fermented meat products.

A fluorescence probe based on molecularly imprinted polymers on red emissive biomass-derived carbon dots (r-BCDs@MIPs) was developed to detect tyramine in fermented meat products. The red emissive biomass-derived carbon dots (r-BCDs) were synthesized by the one-step solvothermal method using discarded passion fruit shells as raw materials. The fluorescence emission peak of r-BCDs was at 670 nm, and the relative quantum yield (QY) was about 2.44%. Molecularly imprinted sensing materials were prepared with r-BCDs as fluorescent centers for the detection of trace tyramine, which showed a good linear response in the concentration range of tyramine from 1 to 40 µg L-1. The linear correlation coefficient was 0.9837, and the limit of detection was 0.77 µg L-1. The method was successfully applied to the determination of tyramine in fermented meat products, and the recovery was 87.17-106.02%. The reliability of the results was verified through high-performance liquid chromatography (HPLC). Furthermore, we combined the r-BCDs@MIPs with smartphone-assisted signal readout to achieve real-time detection of tyramine in real samples. Considering its simplicity and convenience, the method could be used as a rapid and low-cost promising platform with broad application prospects for on-site detection of trace tyramine with smartphone-assisted signal readout.

Traditional Uses, Chemical Constituents and Pharmacological Activities of the Toona sinensis Plant.

Toona sinensis (A. Juss.) Roem., which is widely distributed in China, is a homologous plant resource of medicine and food. The leaves, seeds, barks, buds and pericarps of T. sinensis can be used as medicine with traditional efficacy. Due to its extensive use in traditional medicine in the ancient world, the T. sinensis plant has significant development potential. In this review, 206 compounds, including triterpenoids (1-133), sesquiterpenoids (134-135), diterpenoids (136-142), sterols (143-147), phenols (148-167), flavonoids (168-186), phenylpropanoids (187-192) and others (193-206), are isolated from the T. sinensis plant. The mass spectrum cracking laws of representative compounds (64, 128, 129, 154-156, 175, 177, 179 and 183) are reviewed, which are conducive to the discovery of novel active substances. Modern pharmacological studies have shown that T. sinensis extracts and their compounds have antidiabetic, antidiabetic nephropathy, antioxidant, anti-inflammatory, antitumor, hepatoprotective, antiviral, antibacterial, immunopotentiation and other biological activities. The traditional uses, chemical constituents, compound cracking laws and pharmacological activities of different parts of T. sinensis are reviewed, laying the foundation for improving the development and utilization of its medicinal value.

Mass cytometry-based peripheral blood analysis as a novel tool for early detection of solid tumours: a multicentre study.

OBJECTIVE: Early detection of a tumour remains an unmet medical need, and approaches with high sensitivity and specificity are urgently required. Mass cytometry time-of-flight (CyTOF) is a powerful technique to profile immune cells and could be applied to tumour detection. We attempted to establish diagnostic models for hepatocellular carcinoma (HCC) and pancreatic ductal adenocarcinoma (PDAC). DESIGN: We performed CyTOF analysis for 2348 participants from 15 centres, including 1131 participants with hepatic diseases, 584 participants with pancreatic diseases and 633 healthy volunteers. Diagnostic models were constructed through random forest algorithm and validated in subgroups. RESULTS: We determined the disturbance of systemic immunity caused by HCC and PDAC, and calculated a peripheral blood immune score (PBIScore) based on the constructed model. The PBIScore exhibited good performance in detecting HCC and PDAC, with both sensitivity and specificity being around 80% in the validation cohorts. We further established an integrated PBIScore (iPBIScore) by combining PBIScore and alpha-fetoprotein or carbohydrate antigen 19-9. The iPBIScore for HCC had an area under the curve (AUC) of 0.99, 0.97 and 0.96 in training, internal validation and external validation cohorts, respectively. Similarly, the iPBIScore for PDAC showed an AUC of 0.99, 0.98 and 0.97 in the training, internal validation and external validation cohorts, respectively. In early-stage and tumour-marker-negative patients, our iPBIScore-based models also showed an AUC of 0.95-0.96 and 0.81-0.92, respectively. CONCLUSION: Our study proved that the alterations of peripheral immune cell subsets could assist tumour detection, and provide a ready-to-use detection model for HCC and PDAC.

Aberrant NAD synthetic flux in podocytes under diabetic conditions and effects of indoleamine 2,3-dioxygenase on promoting de novo NAD synthesis.

Nicotinamide adenine dinucleotide (NAD) is an essential coenzyme in the kidney. The first step in de novo NAD synthesis is regulated by indoleamine 2,3-dioxygenase (IDO), a tryptophan-catabolizing enzyme. Here, we investigated NAD synthetic flux and NAD levels in podocytes under diabetic conditions. We also studied the effects of IDO overexpression on NAD synthetic flux and high glucose (HG)-induced podocyte injury. NAD synthetases in the de novo, Preiss-Handler and salvage pathways were analyzed using in vivo single-nucleus RNA sequencing datasets (GSE131882) of control and diabetic kidney disease (DKD). The mRNA levels of these NAD synthetases were measured in vitro in HG-treated podocytes. The effects of IDO on NAD synthesis were examined by transducing cultured podocytes with an adenovirus encoding IDO, and apoptosis, podocyte markers and mobility were investigated. Cellular transcriptome analysis revealed that control podocytes had relatively low levels of NAD synthetases. In DKD podocytes, de novo NAD synthetase levels were further downregulated. IDO levels were virtually undetectable and did not increase in DKD. In vitro experiments confirmed aberrant de novo NAD synthetic flux and decreased IDO levels in HG-treated podocytes. Overexpression of IDO promoted NAD de novo synthesis, reduced NAD-bypass metabolic enzyme, increased NAD content and recovered podocyte injury markers under diabetic conditions. Taken together, our findings suggest that the de novo NAD synthetic flux is aberrant in DKD, and IDO promotes de novo NAD synthesis and NAD levels, as well as alleviates injury in HG-treated podocytes.

Hydrogen inhalation therapy regulates lactic acid metabolism following subarachnoid hemorrhage through the HIF-1α pathway.

The neuroprotective effects of hydrogen have been demonstrated, but the mechanism is still poorly understood. In a clinical trial of inhaled hydrogen in patients with subarachnoid hemorrhage (SAH), we found that hydrogen reduced the accumulation of lactic acid in the nervous system. There are no studies demonstrating the regulatory effect of hydrogen on lactate and in this study we hope to further clarify the mechanism by which hydrogen regulates lactate metabolism. In cell experiments, PCR and Western Blot showed that HIF-1α was the target related to lactic acid metabolism that changed the most before and after hydrogen intervention. HIF-1α levels were suppressed by hydrogen intervention treatment. Activation of HIF-1α inhibited the lactic acid-lowering effect of hydrogen. We have also demonstrated the lactic acid-lowering effect of hydrogen in animal studies. Our work clarifies that hydrogen can regulate lactate metabolism via the HIF-1αpathway, providing new insights into the neuroprotective mechanisms of hydrogen.

Nano-Bricks Assembly Toward 1D Metal Oxide Nanorods.

The rational design of hybrid nanocrystals structures facilitates electronic and energetic communication between different component, which can optimize their specific performance. In this study, an efficient approach for building intricate ZnO@h-CoO nanocomposites and their derivatives is presented, based on a lattice-match/mismatch mechanism. Due to the ultra-low lattice mismatch between ZnO and hexagonal CoO (as low as 0.18%), the h-CoO layer enables epitaxial growth on the ZnO templates, and ZnO can also grow epitaxially outside the CoO layer with ease. Similarly, the thickness of the epitaxial layer and the number of alternating layers can be adjusted arbitrarily. In contrast to h-CoO, the growth of cubic crystalline oxides (such as MnO) on ZnO results in the formation of nanoparticles due to a large mismatch index (following the Volmer-Weber models). Interestingly, when h-CoO is introduced as a further component into the MnO/ZnO composite, the cubic crystalline particles on the surface of the ZnO do not disturb the epitaxial growth of the h-CoO, allowing for the formation of nanocomposites with more components. Furthermore, additional units can be added to the nanocomposite further based on the lattice-match/mismatch mechanism, which is analogous to the building nano-bricks.

The Long-Term Outcome of Laparoscopic Resection for Perihilar Cholangiocarcinoma Compared with the Open Approach: A Real-World Multicentric Analysis.

OBJECTIVE: The aim of this study was to compare the short- and long-term outcomes of laparoscopic surgery (LS) and open surgery (OP) for perihilar cholangiocarcinoma (PHC) using a large real-world dataset in China. METHODS: Data of patients with PHC who underwent LS and OP from January 2013 to October 2018, across 10 centers in China, were extracted from medical records. A comparative analysis was performed before and after propensity score matching (PSM) in the LS and OP groups and within the study subgroups. The Cox proportional hazards mixed-effects model was applied to estimate the risk factors for mortality, with center and year of operation as random effects. RESULTS: A total of 467 patients with PHC were included, of whom 161 underwent LS and 306 underwent OP. Postoperative morbidity, such as hemorrhage, biliary fistula, abdominal abscess, and hepatic insufficiency, was similar between the LS and OP groups. The median overall survival (OS) was longer in the LS group than in the OP group (NA vs. 22 months; hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.02-1.39, p = 0.024). Among the matched datasets, OS was comparable between the LS and OP groups (NA vs. 35 months; HR 0.99, 95% CI 0.77-1.26, p = 0.915). The mixed-effect model identified that the surgical method was not associated with long-term outcomes and that LS and OP provided similar oncological outcomes. CONCLUSIONS: Considering the comparable long-term prognosis and short-term outcomes of LS and OP, LS could be a technically feasible surgical method for PHC patients with all Bismuth-Corlett types of PHC.

High-speed measurement of retinal arterial blood flow in the living human eye with adaptive optics ophthalmoscopy.

We present a technique to measure the rapid blood velocity in large retinal vessels with high spatiotemporal resolution. Red blood cell motion traces in the vessels were non-invasively imaged using an adaptive optics near-confocal scanning ophthalmoscope at a frame rate of 200 fps. We developed software to measure blood velocity automatically. We demonstrated the ability to measure the spatiotemporal profiles of the pulsatile blood flow with a maximum velocity of 95-156 mm/s in retinal arterioles with a diameter >100 µm. High-speed and high-resolution imaging increased the dynamic range, enhanced sensitivity, and improved the accuracy when studying retinal hemodynamics.

Laparoscopic versus open surgery for perihilar cholangiocarcinoma: a multicenter propensity score analysis of short- term outcomes.

BACKGROUND: Laparoscopic surgery (LS) has been increasingly applied in perihilar cholangiocarcinoma (pCCA). In this study, we intend to compare the short-term outcomes of LS versus open operation (OP) for pCCA in a multicentric practice in China. METHODS: This real-world analysis included 645 pCCA patients receiving LS and OP at 11 participating centers in China between January 2013 and January 2019. A comparative analysis was performed before and after propensity score matching (PSM) in LS and OP groups, and within Bismuth subgroups. Univariate and multivariate models were performed to identify significant prognostic factors of adverse surgical outcomes and postoperative length of stay (LOS). RESULTS: Among 645 pCCAs, 256 received LS and 389 received OP. Reduced hepaticojejunostomy (30.89% vs 51.40%, P = 0.006), biliary plasty requirement (19.51% vs 40.16%, P = 0.001), shorter LOS (mean 14.32 vs 17.95 d, P < 0.001), and lower severe complication (CD ≥ III) (12.11% vs. 22.88%, P = 0.006) were observed in the LS group compared with the OP group. Major postoperative complications such as hemorrhage, biliary fistula, abdominal abscess, and hepatic insufficiency were similar between LS and OP (P > 0.05 for all). After PSM, the short-term outcomes of two surgical methods were similar, except for shorter LOS in LS compared with OP (mean 15.19 vs 18.48 d, P = 0.0007). A series subgroup analysis demonstrated that LS was safe and had advantages in shorting LOS. CONCLUSION: Although the complex surgical procedures, LS generally seems to be safe and feasible for experienced surgeons. TRIAL REGISTRATION: NCT05402618 (date of first registration: 02/06/2022).

Hippo/YAP signaling pathway protects against neomycin-induced hair cell damage in the mouse cochlea.

The Hippo/Yes-associated protein (YAP) signaling pathway has been shown to be able to maintain organ size and homeostasis by regulating cell proliferation, differentiation, and apoptosis. The abuse of aminoglycosides is one of the main causes of sensorineural hearing loss (SSNHL). However, the role of the Hippo/YAP signaling pathway in cochlear hair cell (HC) damage protection in the auditory field is still unclear. In this study, we used the YAP agonist XMU-MP-1 (XMU) and the inhibitor Verteporfin (VP) to regulate the Hippo/YAP signaling pathway in vitro. We showed that YAP overexpression reduced neomycin-induced HC loss, while downregulated YAP expression increased HC vulnerability after neomycin exposure in vitro. We next found that activation of YAP expression inhibited C-Abl-mediated cell apoptosis, which led to reduced HC loss. Many previous studies have reported that the level of reactive oxygen species (ROS) is significantly increased in cochlear HCs after neomycin exposure. In our study, we also found that YAP overexpression significantly decreased ROS accumulation, while downregulation of YAP expression increased ROS accumulation. In summary, our results demonstrate that the Hippo/YAP signaling pathway plays an important role in reducing HC injury and maintaining auditory function after aminoglycoside exposure. YAP overexpression could protect against neomycin-induced HC loss by inhibiting C-Abl-mediated cell apoptosis and decreasing ROS accumulation, suggesting that YAP could be a novel therapeutic target for aminoglycosides-induced sensorineural hearing loss in the clinic.

Pharmacokinetics and bioequivalence studies of fluvoxamine maleate tablets in healthy Chinese subjects.

Fluvoxamine is a selective serotonin reuptake inhibitor commonly used for various types of depression. The purpose of this study was to evaluate the pharmacokinetics and bioequivalence of fluvoxamine maleate tablets orally on an empty stomach and after a meal in healthy adult Chinese subjects and to preliminarily evaluate their safety. A single-center, randomized, open-label, two-drug, two-period, crossover, single-dose trial protocol was designed. Sixty healthy Chinese participants were enrolled and randomly classified into fasting (n = 30) and fed groups (n = 30). Each week, subjects took fluvoxamine maleate tablets 50 mg orally once as a test preparation or as a reference preparation on an empty stomach/after meals. To evaluate the bioequivalence of test and reference tables, the concentration of fluvoxamine maleate in the plasma of the subjects at different time points after administration was detected by liquid chromatography-tandem mass spectrometry, and pharmacokinetic parameters including the maximum plasma drug concentration (Cmax ), the time to reach maximum concentration (Tmax ), the area under the plasma concentration-time curve from time 0 to the last measurable concentration (AUC0-t ) and the area under the plasma concentration-time curve from time 0 to infinity (AUC0-∞ ) were calculated. Our data revealed that the 90% confidence intervals of the geometric mean ratio of the test or reference drugs for the Cmax , AUC0-t and AUC0-∞ fell within the acceptance range for bioequivalence (92.30-102.77%). The absorption, measured by AUC, did not show a significant difference between the two groups. There were no suspected serious adverse reactions or serious adverse events over the entire trial. Our results demonstrated that the test and reference tablets were bioequivalent under fasting and fed conditions.

Detection of Rail Defects Using NDT Methods.

The rapid development of high-speed and heavy-haul railways caused rapid rail defects and sudden failure. This requires more advanced rail inspection, i.e., real-time accurate identification and evaluation for rail defects. However, existing applications cannot meet future demand. In this paper, different types of rail defects are introduced. Afterwards, methods that have the potential to achieve rapid accurate detection and evaluation of rail defects are summarized, including ultrasonic testing, electromagnetic testing, visual testing, and some integrated methods in the field. Finally, advice on rail inspection is given, such as synchronously utilizing the ultrasonic testing, magnetic flux leakage, and visual testing for multi-part detection. Specifically, synchronously using the magnetic flux leakage and visual testing technologies can detect and evaluate surface and subsurface defects, and UT is used to detect internal defects in the rail. This will obtain full rail information, to prevent sudden failure, then ensure train ride safety.

Cross-sectional study of the quality of randomized control trials on problem-based learning in medical education.

Problem-based learning (PBL) is increasingly being used in medical education globally, but its effectiveness in teaching remains controversial. A randomized controlled trial (RCT) is the method of choice for evaluating its effectiveness. The quality of an RCT has a significant effect on this evaluation, but to date we have not seen an assessment of the quality of RCTs for PBL. Two researchers searched MEDLINE and EMBASE for RCTs addressing PBL in medical education. The overall quality of each report was measured on a 28-point overall quality score (OQS) based on the 2010 revised Comprehensive Standards for Reporting and Testing (CONSORT) Statement. Furthermore, to study the key factors affecting OQS more effectively, a linear regression model of those factors was established using SPSS. After literature screening, 30 RCTs were eventually included and analyzed. The median OQS was 15 (range, 7-20), which meant that half of the items in the revised 2010 CONSORT statement were poorly reported in at least 40% of the RCTs analyzed. The regression model showed that the year of publication of RCTs and the impact factors of the journals in which they were published were the main factors affecting OQS. The overall quality of reporting of RCTs on PBL teaching in medical education was not satisfactory. Some RCTs were subjectively selective in reporting certain items, leading to heterogeneity in quality. It is expected that statisticians will develop new standards more suitable for evaluating RCTs related to teaching research and that editors and peer reviewers will be required to review the relevant RCTs more strictly.

Enhancing oxidation reaction over Pt-MnO2 catalyst by activation of surface oxygen.

Formaldehyde (HCHO) and carbon monoxide (CO) are both common air pollutants and hazardous to human body. It is imperative to develop the catalyst that is able to efficiently remove these pollutants. In this work, we activated Pt-MnO2 under different conditions for highly active oxidation of HCHO and CO, and the catalyst activated under CO displayed superior performance. A suite of complementary characterizations revealed that the catalyst activated with CO created the highly dispersed Pt nanoparticles to maintain a more positively charged state of Pt, which appropriately weakens the Mn-O bonding strength in the adjacent region of Pt for efficient supply of active oxygen during the reaction. Compared with other catalysts activated under different conditions, the CO-activated Pt-MnO2 displays much higher activity for oxidation of HCHO and CO. This research contributes to elucidating the mechanism for regulating the oxidation activity of Pt-based catalyst.