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【Objective】Fiber Raman Amplifier (FRA) based on multi-pump technology has features of low noise, a wide gain bandwidth, and a controllable gain spectrum shape, which is regarded as an ideal optical relay amplifier for long-haul fiber optic transmission network systems. Intelligent optical amplifiers with adaptive controllable gain are required in dynamic fiber optic transmission network systems. This article introduces a gain control method for FRA based on neural network and numerical solutions of Raman power coupling equations.【Methods】First, the data set containing the signal gains, pump powers and wavelengths in the FRA is collected to train the neural network to establish an approximate mapping relationship between the signal gains and pump parameters. Subsequently, the trained neural network is utilized to determine the initial pump powers and wavelengths of the FRA based on the target gains of the signal. Finally, the pump powers are optimized by solving the numerical solutions of the Raman power coupling equations to improve the accuracy of the FRA output signal gains.【Results】The paper investigates the effect of the flatness of signal gains in each group in the training dataset on the accuracy of FRA output signal gains. When the gain fluctuation of each group signal in the training data is less than 2 dB, the mean and variance of the Root Mean Square Error (RMSE) of the 1 000 sets of test signal gains output by the FRA are 0.230 and 0.010 dB, respectively. Additionally, the mean and variance of the maximum error of the gains are 0.462 and 0.044 dB, respectively.【Conclusion】The results indicate that the proposed method can achieve high-precision FRA gain control, offering a new idea and method for investigating intelligent optical amplifier gain adaptive control in dynamic fiber optic transmission networks.

AIM:To investigate the application of virtual reality(VR)technology in ocular trauma teaching for medical students.METHODS: A total of 90 medical students who participated in the Ophthalmology teaching program between November 2022 and April 2024 were recruited as subjects. Using a case-control method, 45 students in the case group attended traditional ocular trauma teaching program combined with VR virtual simulation experiments, and 45 students in the control group solely attended traditional ocular trauma teaching program. After the teaching practice, the two groups were compared in terms of their examination performance of theoretical knowledge and case analysis, learning ability(evaluated by the Self-Directed Learning Rating Scale), and the satisfaction survey on the quality of teaching; the statistical analyses were performed using t-test or Chi-square test.RESULTS: The scores of theoretical knowledge and case analysis examinations of the case group were significantly higher than those of the control group, and the differences were statistically significant(scores of theoretical knowledge examination: 57.27±2.78 vs 53.91±3.20; scores of case analysis examination: 35.71±3.73 vs 32.67±5.52, both P

In response to the global climate crisis, some countries and regions have established green trade “carbon barriers” that leverage their advantages in carbon emissions accounting and certification to curtail exports of Chinese products. Facing these emerging challenges, China needs to refine its carbon accounting system to contribute to an equitable and cooperative global climate governance and trade system. This study aims to improve China’s carbon accounting system. It summarizes the essence and construction progress of the carbon accounting system, introduces the accounting and reporting requirements of international green trade mechanisms, and employs comparative analysis to examine the differences between China’s carbon market, the European Union’s Carbon Border Adjustment Mechanism, and the “Regulation (EU) 2023/1542 concerning batteries and waste batteries” in terms of accounting boundaries, methodologies, and data support and quality assurance systems. The findings indicate that while China’s carbon market aligns with international green trade mechanisms in terms of accounting methodologies, it lags significantly in its carbon footprint system as well as data support and quality assurance systems. These gaps mean that Chinese export-oriented enterprises struggle to overcome these carbon barriers with the current accounting system, potentially hindering the development of emerging industries. The study suggests that China should adhere to its fundamental stance of opposing unfair green trade barriers and take specific measures to improve the carbon accounting system: (1) enhancing the product-level carbon accounting system, (2) establishing a credible platform for emission factor data, (3) bolstering research support from academic institutions, (4) reinforcing data security management, and (5) improving the carbon accounting and reporting capabilities of affected enterprises.

AIM:To observe the clinical efficacy of 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops in the treatment of dry eyes after pterygium surgery with lacrimal insufficiency.METHODS: A total of 64 cases(64 eyes)of pterygium patients with lacrimal insufficiency were treated with pterygium resection combined with limbal stem cell transplantation, and they were given routine anti-inflammatory and infection prevention treatment postoperatively. In terms of postoperative dry eye treatment, all patients were randomly divided into two groups. The observation group was treated with 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops, and the control group was treated with sodium hyaluronate eye drops. The break-up time of tear film(BUT), fluorescein(FL), Schirmer's Ⅰ test(SⅠt), ocular surface disease index(OSDI)score, central corneal thickness(CCT)changes, adverse reactions and complications were observed and compared between the two groups at different times postoperatively.RESULTS: Both groups of pterygium patients were accompanied with mild to moderate dry eyes with insufficient tear secretion preoperatively. At 2 wk after operation, both groups showed shorter BUT and higher FL score compared with those preoperatively(P0.05). At 4 wk after operation, BUT in the observation group was prolonged, OSDI score was decreased(both P0.05).CONCLUSION: In the treatment of dry eye after pterygium surgery with lacrimal insufficiency, 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops can effectively reduce the postoperative dry eye symptoms, and its clinical effect is better than that of sodium hyaluronate eye drops alone.

The exploration area of Shengli Oilfield was studied， and the difference in geological characteristics of shale oil in continental lake basins in eastern and western China and its influence on the enrichment law were systematically compared. Controlled by paleogeomorphology， paleoclimate， paleowater medium， and other factors in Eocene The Upper Submember of 4th Member of Eocene Shahejie Formation （Es4U）-The Lower Submember of 3rd Member of Eocene Shahejie Formation （Es3L ） of Jiyang Depression， the organic-rich lamellar carbonate shale was widely distributed. The synergistic evolution of hydrocarbon generation of organic-rich clay lamina and reservoir formation of carbonate-rich lamina provided favorable conditions for the large-scale enrichment of free hydrocarbons. The strong rifting of Fengcheng Formation in Hashan area in the northwest margin of Junggar Basin led to strong volcanic activity. Under the combined influence of volcanic eruption materials and paleoclimate， large-scale distribution of organic-rich lamellar alkali-bearing felsic shale lithofacies was observed. More felsic minerals were formed during the evolution of hydrocarbon generation and reservoir formation， accompanied by a large number of matrix dissolution pores and intercrystalline pores， which laid an essential foundation for shale oil enrichment. In the process of multi-stage thrusting in Hashan area， the quasi-in-situ system continued to generate hydrocarbons， with more oil and less gas. The relatively good storage conditions， as well as abnormal high pressure caused by structural overburden pressure and pressurization due to hydrocarbon generation， provide necessary conditions for high shale oil production. Under the background of salt water in Haiji Lake， Lucaogou Formation in the southeastern margin of Junggar Basin was affected by volcanic debris and microorganisms to form the primary lithofacies combination type of organic-rich lamellar shale and organic-poor interlayer dolomite. The organic-rich shale of Lucaogou Formation in the piedmont zone around Bogda Mountain has entered the mature evolution stage， and the structural stability area in the exploration area of Shengli Oilfield was a potential area for shale oil exploration.

AIM: To evaluate the neutrophil-to-lymphocyte ratio(NLR)in patients with retinitis pigmentosa(RP)complicated with cataract, and to explore its correlation with the clinical characteristics of RP patients complicated with cataract.METHODS: The retrospective study included 79 RP patients(125 eyes)complicated with cataract who received cataract surgery at our hospital from January 2008 to December 2018, among which 63 cases(63 eyes)were finally enrolled in the RP complicated with cataract group after the exclusion of patients with early age of onset. Another 63 age- and sex-matched patients(63 eyes)with age-related cataract(ARC)who had cataract surgery during the same period in our hospital were enrolled in the ARC group. The clinical data and NLR were collected, and the correlation of clinical manifestations with NLR in RP patients complicated with cataract was analyzed.RESULTS: The NLR in RP patients complicated with cataract was significantly higher than that in the ARC group [1.79(1.32, 2.27)vs 1.58(1.32, 1.98), P=0.032]. NLR was associated with the severity of posterior subcapsular cataract(PSC), zonular deficiency, and preoperative best-corrected visual acuity(>1 LogMAR). Receiver operating curve showed that NLR ≥1.36 could predict higher degrees(>P1)of RP complicated PSC(AUC=0.803, 95%CI 0.672-0.934, P=0.002), NLR ≥2.12 could predict zonular weakness in RP patients complicated with cataract(AUC=0.796, 95%CI 0.665-0.928, P=0.002), while NLR ≥1.51 could predict RP patients with worse preoperative BCVA(AUC=0.667, 95%CI 0.540-0.793, P=0.015).CONCLUSION: NLR in RP patients complicated with cataract is significantly higher than that in ARC patients, and it is correlated with the clinical manifestations of RP patients with cataract. NLR can be used as a potential predictor to evaluate the severity of clinical manifestations of RP complicated with cataract.

Aiming at the difficult-to-treat high-concentration phosphorus in the spent electroless nickel plating baths, the transformation trends of phosphorus species in catalytic oxidation-reduction, H2O2 oxidation, calcium hypochlorite oxidation, and Fenton oxidation treatment processes were monitored and analyzed. Subsequently, the coagulation/precipitation process was further used to remove TP from the wastewater, and the final TP removal effect was investigated. The experimental results showed that there was no obvious selectivity in the three oxidation treatments of H2O2 oxidation, calcium hypochlorite oxidation, and Fenton oxidation, and a certain concentration of difficult-to-treat H2PO2- remained in the wastewater after the reaction, with TP removal rates of 81.9%, 92.2%, and 96%, respectively. After catalytic oxidation-reduction treatment, almost all phosphorus species in the spent electroless nickel plating baths were converted to HPO32-, and the TP removal rate could reach 99.7% after calcium chloride precipitation treatment. Meanwhile, HPO32- was also a valuable resource that could be utilized. By adding Al2(SO4)3·18H2O to the wastewater treated by catalytic oxidation-reduction, aluminum phosphite products could be recovered, which was of great significance in wastewater treatment, green environmental protection and resource utilization.

Complicated terrains, specific regions, and high wind turbulence intensity frequently trigger shutdown protection of wind turbines due to vibration beyond the designated limit, resulting in serious loss of power generation. This paper aims at reducing the frequency of shutdowns and improving operational stability of wind turbines. Operational characteristics of wind turbines under complicated conditions such as specific regions and strong turbulent wind were analyzed. A fuzzy control approach was proposed based on pertinent theory, to deal with complicated operating conditions at specific sites. This strategy incorporates a vibration recognition algorithm to classify vibration conditions and a fuzzy control algorithm for vibration suppression based on the categorized conditions. Compared with the conventional shutdown or sector-based control methods, the proposed fuzzy control strategy of vibration suppression eliminates the frequent starting and stopping of wind turbines, thus ensuring power generation and improving operational stability. Furthermore, a simulation analysis was performed using Bladed software, taking 3.x MW wind turbines as the research object. Subsequent experimental verification was carried out at a wind farm. In the experiment, the application of the fuzzy vibration suppression control method effectively led to the quick ride-through of the wind turbine amid the complicated operating conditions including the specific region and strong turbulent wind. A 23.87% reduction in the maximum RMS of the front and rear accelerations of the nacelle demonstrated a substantial enhancement in the wind turbine reliability.

Abstract The enactment of the Environmental Protection Tax Law was a major event in the process of China's economic and social development. This law has achieved certain results in the first two years since enactment, but there have also been many problems. During the three-year strict pandemic control period, the normal process of Environmental Protection Tax Law implementation was impacted, causing alienation and reducing the quality of implementation. This study empirically reveals the alienation mechanism in the implementation of the Environmental Protection Tax Law by taking 1000 Chinese tax professionals, and randomly divides the sample equally into two parts, utilizing 500 samples for the initial test and another 500 samples for the robustness test. This research shows that pollutant emission monitoring (correlation coefficient is 0.07), preferential tax policies (correlation coefficient is 0.03) and the quality of tax personnel (correlation coefficient is 0.06) are not conducive to realizing the crowding-out effect of the Environmental Protection Tax Law, while preferential tax policies (correlation coefficient is 0.05), information-sharing platforms (correlation coefficient is 0.06) and the quality of tax personnel (correlation coefficient is 0.05) hinder the incentive effect, and the remaining elements passed the correlation coefficient test within certain confidence intervals. Therefore, the implementation of China's Environmental Protection Tax Law should be improved in the following ways: the accuracy of the environmental protection departments' supervision of pollutant emissions as well as the scientificity and rationality of preferential tax policies should be improved, the construction of environmental protection tax information-sharing platforms should be strengthened, and compound tax collection and management talent should be created.

An accurate survey of field vegetation information facilitates the evaluation of ecosystems and the improvement of remote sensing models. Extracting fractional vegetation cover (FVC) information using aerial images is one of the important areas of unmanned aerial vehicles. However, for a field with diverse vegetation species and a complex surface environment, FVC estimation still has difficulty guaranteeing accuracy. A segmented FVC calculation method based on a thresholding algorithm is proposed to improve the accuracy and speed of FVC estimation. The FVC estimation models were analyzed by randomly selected sample images using four vegetation indices: excess green, excess green minus excess red index, green leaf index, and red green blue vegetation index (RGBVI). The results showed that the empirical model method performed poorly (validating R 2 = 0.655 to 0.768). The isodata and triangle thresholding algorithms were introduced for vegetation segmentation, and their accuracy was analyzed. The results showed that the correlation between FVC estimation under RGBVI was the highest, and the triangle and isodata thresholding algorithms were complementary in terms of vegetation recognition accuracy, based on which a segmentation method of FVC calculation combining triangle and isodata algorithms was proposed. After testing, the accuracy of the improved FVC calculation method is higher than 90%, and the vegetation recognition accuracy is improved to more than 80%. This study is a positive guide to using digital cameras in field surveys.

Semi-flexible concrete has been utilized in highway engineering due to its exceptional pavement performance. This study investigates the proportions of semi-flexible grout, the porosity of asphalt mixture, and the performance of semi-flexible concrete. Initially, 18 sets of semi-flexible grouting materials were proposed through an orthogonal test, resulting in the following material ratio: (cement: mineral powder): water cement ratio: sand cement ratio: Swelling agent: water reducer: flocculant = (0.85:0.15):0.45:0.2:0.04:0.001:0.005. Subsequently, the impact of the 2.36 mm sieve passing rate on the air void of SFAC-13 and SFAC-16 mixtures was analyzed, and a relationship between them was established. Observation of the semi-flexible concrete section and analysis of the grouting rate indicated that the developed grouting material effectively fills the gaps in the asphalt mixture. Lastly, the pavement performance of semi-flexible concrete was compared with SMA-13 asphalt mixture. The results demonstrate that semi-flexible composite concrete exhibits outstanding dynamic modulus, crack resistance, deformation resistance, water stability, and low-temperature performance. Moreover, the material properties of SFAC-13 are akin to those of SFAC-16.

Background: The most effective method for improving the prognosis of lung cancer is the application of low-dose computed tomography (LDCT) for pulmonary nodule screening in populations at high risk. Timely diagnosis and treatment of early-stage lung cancer can contribute to higher long-term survival rates. However, it remains difficult to differentiate malignant from benign pulmonary nodules measuring 8–15 mm, and avoid overtreatment on the one hand and delayed diagnosis on the other hand. In this consensus paper, we aimed to clarify the definition of “high-risk indeterminate pulmonary nodules (IPNs)” and discuss appropriate evaluation and management to facilitate timely diagnosis of lung cancer to improve lung cancer outcome. Direction for future research was discussed. Methods: A multi-disciplinary panel of doctors and IT experts from Asia, Canada and the U.S. were invited to participate. Published evidence and consensus guidelines were used to develop this consensus was clarified. Their evaluation and management were discussed. Findings: The experts believed that the prevalence of pulmonary nodules was very high, and it that was difficult to diagnose early-stage lung cancer due to the small size of the nodules, often leading to delayed diagnosis or overtreatment. To address this issue and to improve long-term outcome, the panel considered important to revise the classification of high-risk IPNs, (1) as pulmonary nodules that cannot be clearly diagnosed with non-surgical biopsy procedures, but is highly suspicious for early-stage lung cancer. The panel also recommends the most responsible should arrange imaging evaluations and follow-ups, taking new technologies into account. Artificial intelligence (AI) assessment based on the Medical Internet of Things (MIoT) can be combined with expert opinion to form a human–computer multidisciplinary team (MDT) that can fully implement the three core procedures of the MIoT, namely, comprehensive perception, reliable transmission, and intelligent processing. This will help to upgrade the non-standard diagnosis and treatment, the so-called “handicraft workshop model”, to a modern assembly-line model that meets international standards. The MIoT technology, which has the potential to realize “simplification of complex problems, digitalization of simple problems, programming of digital problems, and systematization of programming problems”, can promote the homogeneous evaluation of pulmonary nodules by enhancing both the sensitivity and the specificity of detecting early-stage lung cancer, in order to avoid delayed diagnosis and overtreatment. Conclusion: To optimize the evaluation of early-stage lung cancer, and to avoid delayed diagnosis and overtreatment, it is necessary to propose and promote the concept of “high-risk IPNs”. The application of current technologies, AI, and a human–computer MDT, will facilitate improvement in nodule evaluation, transforming the current diagnosis and treatment model, which is akin to production in handicraft workshops, into a modern assembly-line model that meets international standards, and will ultimately result in better prognosis.

Abstract The implementation of the Environmental Protection Tax Law was seriously affected by strict pandemic control. The Environmental Protection Tax Law imposed environmental taxes on enterprises based on measuring their pollution emissions to restrain their bad environmental behaviour and stimulate their green technological innovation ability. However, during the pandemic control period, the green technological innovation ability of enterprises was not developed. Therefore, it is necessary to optimize the environmental regulation effect of the environmental protection tax. This study is based on sample data covering heavily polluting enterprises in China collected from December 20, 2022, to January 7, 2023. It finds that the follow cost effect existed, but the value compensation effect obviously declined, which leading to a decline in the green technological innovation ability of heavily polluting enterprises. The study shows that although strict pandemic control maintained the environmental protection function of the environmental protection tax, it weakened the economic driving function, which will not only damage the long-term economic development potential but also make the environmental protection function unsustainable. Graphical Abstract

The element content， phase composition and interface reaction of nozzle clogging for titanium-bearing welding wire steel SJ-60 during continuous casting were analyzed by means of XRF， XRD and SEM. It is found that the interface of the nozzle is rough and porous due to decarburization reaction， which causes nozzle to be easily invaded by high melting point phases. In addition， the calcium treatment and erosion of refractory during the refining process will produce a large amount of CaTiO3 and MgAl2O4 in the molten steel， and the deposition of both at the interface of the nozzle is the main cause of nozzle clogging. The practice has shown that replacing ordinary ferrosilicon with low titanium and low aluminum ferrosilicon can reduce the aluminum content in steel from 0.008 0%~0.009 5% to 0.005 0%~0.006 5%， which is beneficial for reducing the content of Al2O3 inclusions in steel. Cancelling the refining calcium treatment can reduce the calcium content in steel from more than 0.001 4% to less than 0.000 5%， which is beneficial for reducing the content of CaTiO3 inclusions in steel. Reducing the amount of fluorite from 0.8~1.0 kg/t to 0.3~0.5 kg/t can reduce the erosion of refractory， and the magnesium oxide content in slag is decreased from more than 10% to less than 5%， which is beneficial for reducing the content of MgAl2O4 inclusions in steel. Through the above measures， the problem of nozzle clogging caused by CaTiO3 and MgAl2O4 has been effectively solved，and the number of continuous casting heats is increased from 4-5 heats to more than 12 heats.

Overexpression of methyltransferase-like 3 (METTL3) is significantly correlated with the malignancy of lung cancer (LC). In the present study, we demonstrated that METTL3 had higher levels in LC tissues relative to normal tissues. METTL3 showed superior sensitivity and specificity for diagnosis and identification of LC functions. In addition, silencing METTL3 resulted in enhanced ferroptosis sensitivity, whereas overexpression of METTL3 exhibited the opposite effect. Inhibition of METTL3 impeded LC growth in cell-derived xenografts. Further exploratory studies found that METTL3 stimulated the low expression of transferrin receptor (TFRC), which was critical for ferroptosis sensitization in LC cells induced by silenced METTL3, as silencing of TFRC caused a decrease in negative regulators of ferroptosis (FTH1 and FTL) in METTL3 knockdown A549 and PC9 cells. Finally, we confirmed that METTL3 attenuation effectively maintained the stability of TFRC mRNA. In conclusion, we reported a novel mechanism of METTL3 desensitization to ferroptosis via regulating TFRC, and an appropriate reduction of METTL3 might sensitize cancer cells to ferroptosis-based therapy.

Rechargeable aqueous zinc-ion batteries (AZIBs), a promising energy storage device in the large-scale energy storage market, have attracted extensive attention in recent years due to their high safety, low cost, environmental friendliness, and excellent electrochemical performance. Despite the rapid development of AZIBs technology, challenges such as insufficient energy density and limited cycling life still exist, which hinders the practical application of AZIBs. Due to the critical role that cathode materials play in the electrochemical performance of AZIBs, it is necessary to summarize the progress of cathode materials for AZIBs. In this review, the Zn2+ storage mechanisms of the cathode materials are analyzed. Subsequently, the representative cathode materials are introduced, and their structures and electrochemical performances are compared. The existing problems and improvement strategies of these cathode materials are summarized in detail. Finally, the future challenges and promising prospects for cathode materials are proposed. This review will guide researchers and manufacturers, benefiting them in designing advanced AZIBs for grid-scale energy storage.

Plaque vulnerability has been the subject of several recent studies aimed at reducing the risk of stroke and carotid artery stenosis. Atherosclerotic plaque development is a complex process involving inflammation mediated by macrophages. Plaques become more vulnerable when the equilibrium between macrophage recruitment and clearance is disturbed. Lipoperoxides, which are affected by iron levels in cells, are responsible for the cell death seen in ferroptosis. Ferroptosis results from lipoperoxide-induced mitochondrial membrane toxicity. Atherosclerosis in ApoE(−/−) mice is reduced when ferroptosis is inhibited and iron intake is limited. Single-cell sequencing revealed that a ferroptosis-related gene was substantially expressed in atherosclerosis-modeled macrophages. Since ferroptosis can be regulated, it offers hope as a non-invasive method of treating carotid plaque. In this study, we discuss the role of ferroptosis in atherosclerotic plaque vulnerability, including its mechanism, regulation, and potential future research directions.

Alzheimer’s disease (AD) is a relatively common senile neurodegenerative disease and the main manifestation of senile dementia. In the pathological changes of AD, the asymmetry of the brain also changes. Therefore, finding an early diagnosis method of AD based on asymmetry is the key to the treatment of Alzheimer’s. Magnetic resonance (MR) imaging can quantitatively reflect the structural and functional changes of various tissues in the brain. It has the advantages of non-invasive, high spatial resolution, and non-radiation, and has been widely used in the early diagnosis of AD. In this work, asymmetric images were extracted from multiple brain MR images, and different morphological and texture features were extracted. By establishing a feature selection classification integration model, image features in the image were deeply fused to obtain higher and more stable recognition results than before. By filtering image samples, the corresponding sample feature matrix was obtained. Support vector machine was used for classification, and its classification accuracy had improved significantly compared with that before selection. In the experimental data of normal control group and AD group, the accuracy, sensitivity, and specificity of the feature selection algorithm were 93.34, 90.69, and 95.87%, respectively. In the normal control group and the mild cognitive impairment group, the accuracy, sensitivity, and specificity of the feature selection algorithm in this work were 85.31, 79.68, and 88.54%, respectively. On the whole, the classification accuracy of the feature selection algorithm in this work was much higher than that of other items. In addition, from the classification ability and distribution of asymmetric features, it can be seen that this asymmetric feature had a more significant consistent diagnostic role in clinical practice.

Objectives: To meet the requirements of high cleaning rate and low loss rate. Methods: A small negative pressure winnowing machine for walnut shell and kernel mixtures was developed. Single factor test and response surface optimization method were used to analyze the working parameters of winnowing machine based on such two separation effect indicators as cleaning rate and loss rate. Results: For 1/2 shell kernel, 1/4 shell kernel, 1/8 shell kernel and 1/16 shell kernel materials, the optimal feeding rates were 4.0， 3.5， 3.0， 2.5 kg/min, the fan frequencies were 40， 35， 30， 30 Hz, the feeding inlet heights were 400， 400， 300， 300 mm, respectively. It was seen from the separation effect of different grades of walnut shell materials that 1/2 and 1/4 shell kernel materials had the best separation effect. Conclusion: Shell and kernel separation can be effectively realized by controlling the working parameters of winnowing machine. It is difficult to separate 1/8 and 1/16 shell kernel materials for the overlapping range of suspension speed of shell and kernel materials.

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are key catalytic processes in various renewable energy conversion and energy storage technologies. Herein, we systematically investigated the ORR and OER catalytic activity of the single-atom catalysts (SACs) composed of 4d/5d period transition metal (TM) atoms embedded on MBene substrates (TM-M2B2O2, M = Ti, Mo, and W). We found that TM dominates the catalytic activity compared to the MBene substrates. The SACs embedded with Rh, Pd, Au, and Ir exhibit excellent ORR or OER catalytic activity. Specifically, Rh-Mo2B2O2 and Rh-W2B2O2 are promising bifunctional catalysts with ultra-low ORR/OER overpotentials of 0.39/0.21 V and 0.19/0.32 V, respectively, lower than that of Pt/RuO2 (0.45/0.42 V). Importantly, through machine learning, the models containing 10 element features of SACs were developed to quickly and accurately identify the superior ORR and OER electrocatalysts. Our findings provide several promising SACs for ORR and OER, and offer effective models for catalyst design.

Abstract To provide a basis for further optimization of the polio sequential immunization schedule, this study evaluated the effectiveness of booster immunization with one dose of bivalent oral poliovirus vaccine (bOPV) at 48 months of age after different primary polio immunization schedules. At 48 months of age, one dose of bOPV was administered, and their poliovirus types 1–3 (PV1, PV2, and PV3, respectively)-specific neutralizing antibody levels were determined. Participants found to be negative for any type of PV-specific neutralizing antibody at 24, 36, or 48 months of age were re-vaccinated with inactivated polio vaccine (IPV). The 439 subjects who received a bOPV booster immunization at the age of 48 months had lower PV2-specific antibody levels compared with those who received IPV. One dose of IPV during basic polio immunization induced the lowest PV2-specific antibody levels. On the basis of our findings, to ensure that no less than 70% of the vaccinated have protection efficiency, we recommend the following: if basic immunization was conducted with 1IPV + 2bOPV (especially Sabin strain-based IPV), a booster immunization with IPV is recommended at 36 months of age, whereas if basic immunization was conducted with 2IPV + 1bOPV, a booster immunization with IPV is recommended at 48 months of age. A sequential immunization schedule of 2IPV + 1bOPV + 1IPV can not only maintain high levels of antibody against PV1 and PV3 but also increases immunity to PV2 and induces early intestinal mucosal immunity, with relatively good safety. Thus, this may be the best sequential immunization schedule for polio in countries or regions at high risk for polio.

C23H34O5, orthorhombic, P212121 (no. 19), a = 11.1838(3) Å, b = 11.7824(3) Å, c = 16.3160(5) Å, V = 2149.99(10) Å3, Z = 4, Rgt ${R}_{\mathrm{g}\mathrm{t}}$ (F) = 0.0399, wRref $w{R}_{\mathrm{r}\mathrm{e}\mathrm{f}}$ (F 2) = 0.1097, T = 293 K.

Tropical cyclone (TC) track forecasting is critical for wind risk assessment. This work proposes a novel probabilistic TC track forecasting model based on mixture density network (MDN) and multitask learning (MTL). The existing NN-based probabilistic TC track prediction models focus on directly modeling the distribution of the future TC positions. Multitask learning has been shown to boost the performance of single tasks when the tasks are relevant. This work divides the probabilistic track prediction task into two sub-tasks: a deterministic prediction of the future TC position and a probabilistic prediction of the residual between the deterministic prediction and the actual TC location. The MDN is employed to realize the probabilistic prediction task. Since the target values of the MDN in this work are the residuals, which depend on the prediction result of the deterministic task, a novel training method is developed to train the MTL model properly. The proposed model is tested against statistical and other learning-based models on historical TC data. The results show that the proposed model outperforms other models in making probabilistic predictions. This approach advances TC track forecasting by integrating MDN and MTL, showing promise in enhancing probabilistic predictions and improving disaster preparedness.

Taking Xinjulong Mine in Juye Mining Area as the object, the ventilation difficulties and cooling difficulties were analyzed, and a graded cooling method combining the full air volume cooling at the wellhead and the underground centralized cooling was proposed. The air flow temperature was studied to study its cooling effect. The ventilation route of the mine is extended, the cross section and direction of the tunnel and the bifurcation or convergence point increase, the resistance and local resistance of the wind flow increase, and the heat production of air compression increases. The heat exchange between wind flow and surrounding rock is strengthened, which aggravates the heat damage of high-temperature mines. The full air volume cooling system at the wellhead is used to reduce the air flow temperature at the air inlet of the mine, leaving the high temperature air flow heat on the ground. The underground centralized cooling system is used to solve the air flow cooling of the underground working face. After cooling, the temperature of the air flow at the entrance of the wellbore is kept below 19 ℃. After the air flow enters the bottom of the well, the temperature along the ventilation route is relatively stable, and the overall variation range is within 2 ℃. After adopting the underground centralized cooling system, the temperature difference between the inlet and return air of the working face is 4 ℃. The combination of wellhead cooling and downhole cooling can effectively improve the underground environment.

Objective To investigate the clinical efficacy and prognostic factors of autologous hematopoietic stem cell transplantation (ASCT) for Hodgkin's lymphoma (HL). Methods We retrospectively analyzed the data of 38 patients with HL who underwent ASCT. Kaplan-Meier and Cox methods were used to analyze the curative effect and prognostic factors after transplantation. Results All 38 transplanted patients obtained hematopoietic reconstitution. The CR rates before and after transplantation were 55.3% and 81.6%, respectively, and the 5-year PFS and OS were 76.1% and 79.0%, respectively. Univariate analysis showed that B symptoms, IPS score, pre-transplant remission status, extranodal invasion, and pretreatment regimen were the factors affecting the prognosis of ASCT in patients with HL. Multivariate analysis showed that B symptom was an independent risk factor affecting 5-year PFS. Conclusion ASCT is effective in the treatment of high-risk, relapsed, and refractory patients with HL. B symptom is an independent risk factor affecting the prognosis of transplantation.

The complement cascade plays a “complementing” role in human immunity. However, the potential roles of complement system in impacting molecular and clinical features of hepatocellular carcinoma (HCC) remain unclear. In this study, eleven public datasets are analyzed to compare the complement status between normal and cancerous samples based on 18 classical complement-associated genes. The complement scores are constructed to quantify complement signatures of individual tumors. HCC patients in the The Cancer Genome Atlas (TCGA) cohort are focused to perform systematical analyses between complement status and immune infiltration, miRNA expression, DNA methylation, clinicopathological features, and drug response. The results show that the complement scores in normal tissues are dramatically higher than those of tumor tissues. Tumor samples in the TCGA cohort are classified into complement score-low and score-high groups. Pathway analysis reveals that tumor-promoting pathways are typically inhibited in complement score-high group. This study also shows that tumor-killing immune cells, such as CD8 + T cells and natural killer cells are abundant and tumor-suppressing miRNAs are upregulated in complement score-high samples. In addition, we identify that complement scores are negatively correlated with certain clinical features, including pathological grade, clinical-stage, and portal vein invasion. Moreover, various molecular features together with complement scores are found to be correlated with response to anti-cancer drugs. This study provides a comprehensive and multidimensional analysis conducive to understanding the role of complement in cancer.

Over the past decade, two-dimensional (2D) Ti3C2Tx MXenes demonstrated attractive characteristics such as high electrical conductivity, tunable layered structure, controllable interfacial chemical composition, high optical transparency, and excellent electromagnetic wave absorption, enabling Ti3C2Tx MXenes as promising electrode materials in energy storage devices. Among these devices, flexible energy storage devices have attracted wide attention and developed rapidly due to the synchronously excellent electrochemical and mechanical properties. This review summarizes the recent progress of Ti3C2Tx MXenes pertaining to novel material preparation and promising applications in energy storage and conversion including batteries, supercapacitors, solar cells, and solar steam generation. This work aims to provide an in-depth and reasonable understanding of the relationship between the unique nanostructure/chemical composition of Ti3C2Tx MXenes and competitive electrochemical properties, which will facilitate the development of 2D Ti3C2Tx MXenes for practical energy storage and solar energy conversion devices.

Rapid determination of moisture content is an important requirement to ensure the production quality of puffs. In this paper, the NIR spectra of 130 modeling samples and 30 validation samples were collected, using IAS Online-S100 Near Infrared Spectroscopy Analyzer. The moisture analysis model of puff was established using spectral pretreatment and partial least square method. The results showed that determination coefficient R2, root mean square error of correction set (RMSEC), root mean square error of interactive verification (RMSECV) and root mean square error of prediction set (RMSEP) of the model are 0.88, 0.49%, 0.55% and 0.57% respectively, when using moving window smoothing method & SNV as spectral pretreatment method and the best principal factors was 9. The prediction error of the model is within ±1.3, and the accuracy meets the needs of the factory.

ObjectiveTo analyze the levels of dioxin contamination in pork and pork liver from five provinces of China： A， B， C， D， and E， and evaluate the dietary exposure of the population， aiming to provide fundamental data for the future formulation of national limit standards of PCDD/Fs.MethodsA total of 146 pork and pork liver samples were collected during 2013 to 2019. According to the national standard method "Determination of Toxicity Equivalent of Dioxins and Analogues in Foods" （GB 5009.205-2013）， 17 polychlorinated dibenzo-p-dioxin/furans （PCDD/Fs） in food samples were detected by isotope dilution chromatography/high resolution dual-focusing magnetic mass spectrometry （HRGC/HRMS）. Based on the food consumption data， the dietary exposure via pork for the population was assessed.ResultsThe median TEQ concentration of dioxin in pork and pork liver samples was 0.106 pg/g·fat and 2.32 pg/g·fat， respectively. The concentration of PCDD/Fs in pork in various regions were sequentially decreased by A （0.859 pg/g·fat）>D（0.145 pg/g·fat）>C（0.097 4 pg/g·fat）>B（0.039 9 pg/g·fat）>E（0.023 pg/g·fat）， and the decreased order of PCDD/F levels in pork liver samples from various regions was A （3.616 pg/g·fat）>B （1.84 pg/g·fat）>D（1.313 pg/g·fat）>E（0.85 pg/g·fat）. The patterns for 17 congeners of PCDD/Fs in pork and pork liver samples were similar and OCDD was the dominant congener， accounting for 95% and 90% of the total mass concentrations， respectively. As for the TEQ concentrations， the congener patterns of PCDD/Fs in pork and pork liver samples were inconsistent. In addition， it also varied greatly in the congener patterns of PCDD/Fs for the same class of food samples from different regions. The median intakes of PCDD/Fs via pork for local residents in the five regions ranged from 0.192 to 2.054 pg/kg·bw/month， which were all lower than the PTMI value recommended by JECFA （70 pg/kg·bw/m）.ConclusionPCDD/Fs contamination in pork and pork liver existed in some areas of China. Spatial difference in PCDD/F levels was observed among the five areas and higher levels of PCDD/Fs for pork existed in developed areas . Residents showed low risk of dioxin exposure via pork intake overall. It is necessary to take long-term monitoring on the levels of PCDD/Fs in retailed food covered the larger area in China， and comprehensive exposure assessments of dioxins from various food categories should be further carried out to ensure the food safety of livestock and human health in the future.

To assess the characteristics of 13N decay, a monitoring method of the primary loop leakage rate based on the γ-γ coincidence method was proposed. In this work, sampling and measurement devices were designed, in which NaI (Tl) crystals were used as coincidence detectors. The Geant4 simulation method was used to study the relationship between the efficiency e and capacity V change of different devices, and the eV value under the corresponding capacity was obtained. According to the value of eV, the optimal sampling and measurement device was determined, and then the detection efficiency of the device was calibrated experimentally. Taking the 600 000 kW reactor of Qinshan Phase II as the research object, the lower limit of detection was discussed. When the sampling point was located in the fume hood of the control rod drive mechanism, the theoretical lower limit of the coincidence method was 0.756 Lh-1.

Abstract The past years have witnessed the vigorous development of immunotherapy, mainly immune checkpoint inhibitors (ICIs) targeting the programmed cell death-1 (PD-1) protein and its ligand, PD-L1, and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4). Indeed, ICIs have largely revolutionized the management and improved the prognosis of patients with intermediate and advanced hepatocellular carcinoma (HCC). However, biomarker-based stratification of HCC patients for optimal response to ICI treatment is still of unmet need and again, there exists the necessity to dynamically monitor treatment effect in real-time manner. The role of conventional biomarkers in immunotherapy surveillance is largely limited by spatial and temporal tumor heterogeneity whereas liquid biopsy seems to be promising to circumvent tumor heterogeneity to identify candidate patients who may response to immunotherapy, to dynamically monitor treatment effect and to unveil resistance mechanism. Herein, we provide a thorough review about the potential utility of liquid biopsy in immunotherapy for HCC and discuss its future perspectives.

Nano-sized lanthanum hexaboride (LaB6)@ titanium dioxide (TiO2) particles with a core–shell structure has been successfully synthesized via a simple sol–gel method. LaB6@TiO2 particles were used as filler in polyvinyl butyral (PVB) matrix and performance of the TiO2 shell was evaluated. The core–shell nanoparticles were characterized for morphology and structure properties. X-ray diffraction and transmission electron microscope testing results confirm the formation of LaB6–TiO2 core–shell structure. In composite film, LaB6 improved the thermo-decomposing temperature of PVB matrix from 369.2 to 372.8°C, while the same amount of LaB6@TiO2 further increased the temperature to 381.0°C. In addition, TiO2 shell redshifted the maximum transmittance of the film from 605 to 669 nm in the visible region. In the near infrared region, its absorption peak shifted from 1,466 to 1,476 nm. This result will be helpful for the development of transparent and thermal insulating materials.

Tapered fiber (TF) and D-shaped fiber (DF) are two types of widely investigated devices in facilitating evanescent-field interactions with external materials. Although they have been found to be particularly useful in various ultrafast regimes, to date there is still no clear or systematic investigation on their local nonlinearities as well as the exerted influences on ultrafast behaviors. Herein, we present such thorough investigation through local nonlinearity engineering on TF and then in contrast with a DF as a reference. Optically deposited black phosphorus quantum dots (BPQDs) are used for saturable absorption. The nanometer-scale extremely small sizes of the BPQDs helpfully eliminate size-induced uncertainties or distortions during both device fabrication and the latter light–matter interaction. For the TF, in the experiment, it is found that the local nonlinear effect starts to be rather appreciable as the TF shrinks to a moderate thickness. Remarkably in comparison, the local nonlinearity of the DF itself can even be neglected reasonably, but after coating with BPQDs, it possesses a much larger modulation depth than any of the used BPQDs-coated TFs with different thicknesses/lengths. Further, we theoretically analyze the related locally nonlinear effects and reveal, for the first time, the direct origin of saturable absorption with evanescent-field-based general structures.

Objective: Using wheat bran as raw material, the extruded bran is obtained by extrusion stabilization treatment, and the best drying method for extruded bran is determined. Methods: The effects of three drying methods （fluidized bed drying, microwave drying, hot air drying） were studied on the basic components of extruded bran, water holding capacity, water solubility, swelling power, oil holding power, color value and other physical and chemical properties, oxidation resistance, total phenols and total flavonoids; Using antioxidant, total phenols and total flavonoids as indicators to determine the best drying method for extruded bran. Results: The three drying methods have no significant effect on the crude protein, crude fat, ash and TDF of the extruded bran; Compared with fluidized bed drying, microwave drying and hot air drying can increase the content of starch and crude fiber; Drying has an effect on extrusion, and the influence of the water solubility of extruded wheat bran is: hot-air drying ＞ fluidized bed drying ＞ microwave drying; Compared with microwave drying and hot-air drying, fluidized bed drying can improve the expansion force and oil holding capacity of extruded bran; Compared with fluidized bed drying and hot-air drying, microwave drying can improve the water holding capacity, oxidation resistance, total phenol and total flavonoids content of extruded bran, and reduce brightness and whiteness. Conclusion: The best drying method is determined to be microwave drying.

Appropriate biomimetic scaffolds created via 3D bioprinting are promising methods for treating damaged menisci. However, given the unique anatomical structure and complex stress environment of the meniscus, many studies have adopted various techniques to take full advantage of different materials, such as the printing combined with infusion, or electrospining, to chase the biomimetic meniscus, which makes the process complicated to some extent. Some researchers have tried to tackle the challenges only by 3D biopringting, while its alternative materials and models have been constrained. In this study, based on a multilayer biomimetic strategy, we optimized the preparation of meniscus-derived bioink, gelatin methacrylate (GelMA)/meniscal extracellular matrix (MECM), to take printability and cytocompatibility into account together. Subsequently, a customized 3D bioprinting system featuring a dual nozzle + multitemperature printing was used to integrate the advantages of polycaprolactone (PCL) and meniscal fibrocartilage chondrocytes (MFCs)-laden GelMA/MECM bioink to complete the biomimetic meniscal scaffold, which had the best biomimetic features in terms of morphology and components. Furthermore, cell viability, mechanics, biodegradation and tissue formation in vivo were performed to ensure that the scaffold had sufficient feasibility and functionality, thereby providing a reliable basis for its application in tissue engineering.

This study enumerates the stage-by-stage usefulness of the addition of a servo system to the lateral steel support system to improve the lateral load resistance of steel support members on an actual deep excavation site. A field case is found in a project of Triumph Unit building block, where a 14.20 m basement is constructed near the existing high traffic highway and high-rise buildings. It is therefore important to choose an appropriate excavation pit lateral support system to ensure the safety during excavation. At the field site, the basement execution works are divided into 5 construction stages. The excavated pit wall displacement and bending moment caused by excavation process are controlled using the steel material servo combined load support at each respective construction stage. The results from field work authenticate the steel servo enhanced support system application on an actual basement construction site. With the application of steel servo enhanced axial loading capacities, the excavated pit induced lateral displacement and bending moment are effectively restrained within the project acceptable alert limits. Moreover, the obtained field results correlate well with previous and current numerical literature data. This study provides a unique chance to advance the steel material servo enhanced support system application to actual deep basement projects with acceptable displacement and bending moment control requirements.

Since the Harvard Brain Death Criteria was published in 1968, many guidelines and diagnostic procedures of Brain Death/Death by Neurologic Criteria (BD/DNC) have been published throughout the world, and these determination criteria have been constantly revised and updated. The World Brain Death Project published the "Determination of Brain Death/Death by Neurologic Criteria" in 2020 to unify clinical practice across countries and improve the rigorousness of BD/DNC determination. This article analyzes and interprets these "Determination of Brain Death/Death by Neurologic Criteria" (version 2020) to clarify the concept of BD/DNC, the minimum clinical criteria for Determination of BD/DNC, ancillary testing, and the pediatric/neonatal BD/DNC, and to compare with the current practical guidance for determination of brain death in China, and analyze the differences between China and foreign countries, so as to provide reference for medical personnel in related professions in China. doi:10.3969/j.issn.1672⁃6731.2021.04.003

The scientific prediction of the TBM penetration rate is of great significance to the selection of hydraulic tunnel construction methods, construction schedule and cost estimation. In view of the high nonlinearity, fuzziness and complexity of TBM excavation process, and in order to improve the prediction accuracy and computational efficiency, the partial least squares regression (PLSR) has been applied to extract the principal components of the influencing parameters. Then the deep neural network (DNN) is employed to train and forecast the TBM penetration rate. A prediction model of TBM penetration rate based on the coupled method of PLSR and DNN is proposed. Based on the measured data of the double-shield TBM construction of a water conveyance tunnel in the Lanzhou water source construction project, six impact parameters including the rock uniaxial compressive strength, rock uniaxial tensile strength, cutter head thrust, cutter head speed, rock mass integrity coefficient and rock Cerchar abrasiveness index are selected to verify the prediction reasonability of the model. The fitting and prediction accuracy of the different prediction methods are compared and analyzed. The research results show that the PLSR can effectively overcome the problem of multiple collinearity between the independent variables. The extracted principal components are trained as the input layer of the DNN, which simplifies the structure of the neural network. The PLSR-DNN coupled model effectively avoids the over-fitting and inadequate fitting problems. It has the characteristics of fast convergence, stable solution and high fitting accuracy. The average relative fitting error of the PLSR-DNN prediction model is 2.96%, and the average relative prediction error is 3.27%. The fitting accuracy and prediction accuracy of the PLSR-DNN prediction model is significantly higher than those of PLSR model alone, BP neural network model and SVR model, respectively.

The protection of blockchain wallet is the basis of secure transaction in blockchain. Private key is the core of wallet security. The private key cannot be protected based on a reliable third party. Therefore, the loss or theft of private key will lead to the loss of customer property. To solve this problem, a distributed protection and recovery mechanism is proposed. Every wallet private key is divided into multiple key fragments by threshold key mechanism according to the network scale. Even if the wallet is offline, the threshold number of holders holding key fragements from the wallet cooperates to distribute key fragments to new members, which keeps the update of key fragments synchronized. When the key is lost, the number of private key fragments exceeding the threshold of half the blockchain member scale can ensure the recovery of the private key. The dynamic threshold mechanism design makes the attacker must attack more than half of the members to steal the wallet private key successfully. The hash based shard key tree can quickly detect the number of key fragments smaller than the specified size, the invalid key fragments are detected and eliminated efficiently in the network, and the integrity of the global private key is guaranteed. The suggested method of wallet protection is feasible from the aspect of secure storage.