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为了促进国内橄榄油市场的健康发展，对掺伪同样存在天然类胡萝卜素的低温压榨菜籽油的特级初榨橄榄油进行了定量鉴别研究。采用共聚焦拉曼光谱技术对不同掺伪浓度油样进行测试，基于密度泛函理论对油样的拉曼光谱峰的归属进行了理论分析，并对拉曼光谱数据进行主成分分析（PCA），然后利用支持向量机（SVM）构建PCA-SVM模型。另外，对PCA-SVM模型的检出限进行了研究。结果表明：特级初榨橄榄油与低温压榨菜籽油的拉曼光谱存在一定差异，最明显的光谱差异主要集中在谱峰1 008、1 161、1 528 cm-1和谱段2 800～3 000 cm-1内，与密度泛函理论对不同油样拉曼光谱峰的分析一致；不考虑类胡萝卜素特征信号建立的PCA-SVM模型决定系数大于0.989，均方根误差小于2.990%，检出限为2%（低温压榨菜籽油体积分数）;在特级初榨橄榄油掺伪定量分析中，考虑类胡萝卜素的特征信号有助于提高模型预测精度，但仅限于掺伪低价植物油中无类胡萝卜素存在的情况;PCA-SVM模型在不考虑类胡萝卜素特征信号的情况下依然具有良好的定量预测效果。综上，所建立的PCA-SVM模型可以用于掺伪2%以上低温压榨菜籽油的特级初榨橄榄油的定量鉴别。To promote the healthy development of the domestic olive oil market, a study was conducted on quantitatively identifying extra virgin olive oil adulterated with low-temperature pressed rapeseed oil containing natural carotenoids. The confocal Raman spectroscopy technology was used to test oil samples with different adulteration amounts. Theoretical analysis was conducted on attributing Raman spectral peaks of different oil samples based on density functional theory. Principal component analysis (PCA) was performed on the Raman spectral data, and then the support vector machine (SVM) was used to construct a PCA-SVM model. In addition, the detection limit of the PCA-SVM model was studied. The results showed that there was difference in the Raman spectra of extra virgin olive oil and low-temperature pressed rapeseed oil, and the most apparent spectral differences mainly concentrated in the spectral peaks 1 008, 1 161, 1 528 cm-1 and spectral bands 2 800-3 000 cm-1, which was consistent with the analysis of Raman spectral peaks of different oil samples using density functional theory. The PCA-SVM model established without considering the characteristic signals of carotenoids had a coefficient of determination greater than 0.989, and the root mean square error was lower than 2.990%, and the detection limit was 2% (volume fraction of low-temperature pressed rapeseed oil). In the quantitative analysis of extra virgin olive oil adulteration, considering the characteristic signals of carotenoids could help to improve the prediction accuracy of the model, but it was only limited to the absence of carotenoids in adulterated low-price vegetable oils. The PCA-SVM model still had good quantitative prediction performance even when the characteristic signals of carotenoids were not considered. In summary, the established PCA-SVM model can be used to quantitatively identify extra virgin olive oil adulterated with over 2% low-temperature pressed rapeseed oil.

As the number of electric vehicles (EVs) increases, massive numbers of EVs have started to gather in commercial parking lots to charge and discharge, which may significantly impact the operation of the grid. There may also be a deviation in the departure time of charged and discharged EVs in commercial parking lots. This deviation can lead to insufficient battery energy when the EVs leave the parking lot. This study uses the simulation software AnyLogic to build a commercial parking lot multi-agent simulation model, and the agent-based model can fully reflect the autonomy of individual EVs. Based on this simulation model, we propose an EV scheduling algorithm. The algorithm contains two main agents. The first is the power distribution center agent (PDCA), which is used to coordinate the energy output of photovoltaic (PV), energy storage system (ESS), and distribution station (DS) to solve the problem of grid overload. The second is the scheduling center agent (SCA), which is used to solve the insufficient battery energy problem due to EVs’ random departures. The SCA includes two stages. In the first stage, a priority scheduling algorithm is proposed to emphasize the fairness of EV charging. In the second stage, a genetic algorithm is used to accurately determine the time interval between charging and discharging to ensure the maximum benefit of EV owner. Finally, simulation experiments are conducted in AnyLogic, and the results demonstrate the superiority of the algorithm over the classical algorithm.

TiO2 photocatalyst has the advantages of high catalytic activity, suitable energy band potential, high chemical stability, high photoelectric conversion efficiency, high safety and non-toxicity, which exhibits excellent performances in photocatalytic degradation of organic wastewater. However, it is difficult to separate and recover TiO2 photocatalyst from the reactive system. Interestingly, magnetic TiO2 prepared by combining TiO2 with superparamagnetic ferromagnetic particles can overcome this shortcoming. In this review, the preparation method and the photocatalytic mechanism of magnetic TiO2 were summarized. Moreover, the catalytic mechanisms of the modified binary, ternary and multicomponent magnetic TiO2 composite photocatalysts were compared, and the effects of different magnetic substrates on the degradation activity were discussed. Besides the applications in the wastewater treatment, the development trend and application prospects were prospected. [ABSTRACT FROM AUTHOR]

Objectives: Chest x‐ray (CXR) plays an important role in childhood tuberculosis (TB) diagnosis, but access to quality CXR remains a major challenge in resource‐limited settings. Digital CXR (d‐CXR) can solve some image quality issues and facilitate their transfer for quality control. We assess the implementation of introducing d‐CXR in 12 district hospitals (DHs) in 2021–2022 across Cambodia, Cameroon, Ivory Coast, Mozambique, Sierra Leone and Uganda as part of the TB‐speed decentralisation study on childhood TB diagnosis. Methods: For digitisation of CXR, digital radiography (DR) plates were setup on existing analogue radiography devices. d‐CXR were transferred to an international server at Bordeaux University and downloaded by sites' clinicians for interpretation. We assessed the uptake and performance of CXR services and health care workers' (HCW) perceptions of d‐CXR implementation. We used a convergent mixed method approach utilising process data, individual interviews with 113 HCWs involved in performing or interpreting d‐CXRs and site support supervision reports. Results: Of 3104 children with presumptive TB, 1642 (52.9%) had at least one d‐CXR, including 1505, 136 and 1 children with one, two and three d‐CXRs, respectively, resulting in a total of 1780 d‐CXR. Of them, 1773 (99.6%) were of good quality and 1772/1773 (99.9%) were interpreted by sites' clinicians. One hundred and sixty‐four children had no d‐CXR performed despite attending the radiography department: 126, 37 and 1 with one, two and three attempts, respectively. d‐CXRs were not performed in 21.6% (44/203) due to connectivity problem between the DR plate captor and the computer. HCW reported good perceptions of d‐CXR and of the DR plates provided. The main challenge was the upload to and download from the server of d‐CXRs due to limited internet access. Conclusion: d‐CXR using DR plates was feasible at DH level and provided good quality images but required overcoming operational challenges. [ABSTRACT FROM AUTHOR]

Abstract Background In high tuberculosis (TB) burden settings, there is growing evidence that TB is common in children with pneumonia, the leading cause of death in children under 5 years worldwide. The current WHO standard of care (SOC) for young children with pneumonia considers a diagnosis of TB only if the child has a history of prolonged symptoms or fails to respond to antibiotic treatments. As a result, many children with TB-associated severe pneumonia are currently missed or diagnosed too late. We therefore propose a diagnostic trial to assess the impact on mortality of adding the systematic early detection of TB using Xpert MTB/RIF Ultra (Ultra) performed on nasopharyngeal aspirates (NPA) and stool samples to the WHO SOC for children with severe pneumonia, followed by immediate initiation of anti-TB treatment in children testing positive on any of the samples. Methods TB-Speed Pneumonia is a pragmatic stepped-wedge cluster randomized controlled trial conducted in six countries with high TB incidence rate (Côte d’Ivoire, Cameroon, Uganda, Mozambique, Zambia and Cambodia). We will enrol 3780 children under 5 years presenting with WHO-defined severe pneumonia across 15 hospitals over 18 months. All hospitals will start managing children using the WHO SOC for severe pneumonia; one hospital will be randomly selected to switch to the intervention every 5 weeks. The intervention consists of the WHO SOC plus rapid TB detection on the day of admission using Ultra performed on 1 nasopharyngeal aspirate and 1 stool sample. All children will be followed for 3 months, with systematic trial visits at day 3, discharge, 2 weeks post-discharge, and week 12. The primary endpoint is all-cause mortality 12 weeks after inclusion. Qualitative and health economic evaluations are embedded in the trial. Discussion In addition to testing the main hypothesis that molecular detection and early treatment will reduce TB mortality in children, the strength of such pragmatic research is that it provides some evidence regarding the feasibility of the intervention as part of routine care. Should this intervention be successful, safe and well tolerated, it could be systematically implemented at district hospital level where children with severe pneumonia are referred. Trial registration ClinicalTrials.gov, NCT03831906 . Registered 6 February 2019.

Abstract Background The role(s) of epigenetic reprogramming in gastric cancer (GC) remain obscure. This study was designed to identify methylated gene markers with prognostic potential for GC. Methods Five datasets containing gene expression and methylation profiles from GC samples were collected from the GEO database, and subjected to meta-analysis. All five datasets were subjected to quality control and then differentially expressed genes (DEGs) and differentially expressed methylation genes (DEMGs) were selected using MetaDE. Correlations between gene expression and methylation status were analysed using Pearson coefficient correlation. Then, enrichment analyses were conducted to identify signature genes that were significantly different at both the gene expression and methylation levels. Cox regression analyses were performed to identify clinical factors and these were combined with the signature genes to create a prognosis-related predictive model. This model was then evaluated for predictive accuracy and then validated using a validation dataset. Results This study identified 1565 DEGs and 3754 DEMGs in total. Of these, 369 were differentially expressed at both the gene and methylation levels. We identified 12 signature genes including VEGFC, FBP1, NR3C1, NFE2L2, and DFNA5 which were combined with the clinical data to produce a novel prognostic model for GC. This model could effectively split GC patients into two groups, high- and low-risk with these observations being confirmed in the validation dataset. Conclusion The differential methylation of the 12 signature genes, including VEGFC, FBP1, NR3C1, NFE2L2, and DFNA5, identified in this study may help to produce a functional predictive model for evaluating GC prognosis in clinical samples.

Titanium dioxide (TiO2) photocatalysts, characterized by exceptional photocatalytic activity, high photoelectric conversion efficiency, and economic viability, have found widespread application in recent years for azo dye degradation. However, inherent constraints, such as the material's limited visible light absorption stemming from its bandgap and the swift recombination of charge carriers, have impeded its broader application potential. Encouragingly, these barriers can be mitigated through the modification of TiO2. In this review, the common synthesis methods of TiO2 are reviewed, and the research progress of TiO2 modification technology at home and abroad is discussed in detail, including precious metal deposition, transition metal doping, rare earth metal doping, composite semiconductors, and composite polymers. These modification techniques effectively enhance the absorption capacity of TiO2 in the visible region and reduce the recombination rate of carriers and electrons, thus significantly improving its photocatalytic performance. Finally, this paper looks forward to the future development direction of TiO2 photocatalytic materials, including the exploration of new modified materials, in-depth mechanism research, and performance optimization in practical applications, to provide useful references for further research and application of TiO2 photocatalytic materials. [ABSTRACT FROM AUTHOR]

Microgrids integrated with distributed generation provide energy intensive enterprises (EIEs) with a solution to cut down their total system costs. However, unreasonable capacity allocation of power supply in industrial microgrid may result in capacity shortage or excess, thus leading to uneconomical solutions. Considering carbon emission permits and renewable energy access on demand side, this paper analyses and evaluates the long-term impacts of power supply capacity on economic benefits and carbon emission. The power suppliers consist of industrial self-generation, wind power generation and power grid. A HOMER software based industrial microgrid model is designed, and time series simulation of the model for a cycle of 10 years is performed to provide numerical analysis. The simulation results with sensitivity analysis show that optimal capacity planning of power supply can lead to considerable economical and ecological benefits under carbon emission permits; besides, it can also be conducive to peak load shedding for power grid.

The inflow forecasting is one of the most important technologies for modern hydropower station. Under the joint influence of soil, upstream inflow, and precipitation, the inflow is often characterized by time lag, nonlinearity, and uncertainty and then results in the difficulty of accurate multistep prediction of inflow. To address the coupling relationship between inflow and the related factors, this paper proposes a long short-term memory deep learning model based on the Bagging algorithm (Bagging-LSTM) to predict the inflows of future 3 h, 12 h, and 24 h, respectively. To validate the proposed model, the inflow and related weather data come from a hydropower station in southern China. Compared with the classical time series models, the results show that the proposed model outperforms them on different accuracy metrics, especially in the scenario of multistep prediction.

This article considers a robot path planning problem originated from a robot factory inspection scenario. In the problem, the robot is in a dynamic uncertain environment, that is, a moving target object and several static and dynamic obstacles. An inertial positioning strategy is proposed to enable the robot to predict the position of the target in advance. From this predicted position, the robot path is generated by cubic spline interpolation, and then an improved particle swarm optimization algorithm with a random positive feedback factor in velocity updating optimizes the path. The experimental results show that the proposed method can successfully avoid the obstacles and reach the target object. In addition, the inertial positioning strategy and the improvement of particle swarm optimization can effectively shorten the path of the robot.

The routine tuberculosis (TB) surveillance system in Cambodia has been strengthened under the National TB Programme (NTP). This paper provides an overview of the TB surveillance data for Cambodia at the national level for the period 2000 to 2013 and at the subnational level for 2013. The proportion of the total population that were screened for TB rose from 0.4% in 2001 to 1.1% in 2013, while the smear-positivity rate decreased from 28.9% to 8.1% in the same period. The total number of notified TB cases increased steadily from 2000; this has stabilized in recent years with 39 055 cases notified in 2013. The proportion of all TB cases that were smear-positive decreased from 78% in 2000 to 36% in 2013. Case notification rates (CNRs) for all forms of TB and new smear-positive TB in 2013 were 261 and 94 per 100 000 population, respectively. Higher CNRs were found in the north-west and south-east parts of the country and were higher for males especially in older age groups. The increase in TB screening, decline in the smear-positive rate and decline in notified smear-positive TB cases likely reflect a long-term positive impact of the NTP. A negative correlation between the proportion of the population screened and the smear-positivity rate at the subnational level helped identify where to find undiagnosed cases. Subnational differences in case notification of the elderly and in children provide more specific targets for case-finding and further encourage strategic resource allocation.

Despite the World Health Organization recommending the use of rapid molecular tests for diagnosing tuberculosis (TB), uptake has been limited, partially due to high cartridge costs. Other infectious disease programs pool specimens to save on diagnostic test costs. We tested a sputum pooling strategy as part of a TB case finding program using Xpert MTB/RIF Ultra (Ultra). All persons were tested with Ultra individually, and their remaining specimens were also grouped with 3−4 samples for testing in a pooled sample. Individual and pooled testing results were compared to see if people with TB would have been missed when using pooling. We assessed the potential cost and time savings which different pooling strategies could achieve. We tested 584 individual samples and also grouped them in 153 pools for testing separately. Individual testing identified 91 (15.6%) people with positive Ultra results. One hundred percent of individual positive results were also found to be positive by the pooling strategy. Pooling would have saved 27% of cartridge and processing time. Our results are the first to use Ultra in a pooled approach for TB, and demonstrate feasibility in field conditions. Pooling did not miss any TB cases and can save time and money. The impact of pooling is only realized when yield is low.