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Membraneless microfluidic fuel cells (MFCs) have garnered tremendous interest as micropower devices, which exploit the colaminar nature of two aqueous electrolytes to separate the anode and cathode and avoid the membrane usually used in a fuel cell. Our previous research shows that the performance of FeCl3-based MFCs with catalyst-free cathodes is mainly limited by the cathode. To improve the power output of these MFCs, we activated the carbon paper cathode by an electrochemical method in the three solutions (Na2SO4, NaOH, and H2SO4) to improve the electrochemical characteristics of the carbon paper cathode. The surface functionalities and defects, reduction activation of iron ions as the oxidant, cathode resistance, and performance of FeCl3-based MFCs were measured and compared. Our work shows that the electrochemical activation of the carbon paper in different solutions is a simple and effective method to enhance the electrochemical characteristics of the carbon paper cathode and improve the performance of the FeCl3-based MFC. Also, the MFC with the carbon paper cathode activated in the H2SO4 solution reaches the optimum performance: 235.6 mW cm-3 in volumetric power density and 1063.33 mA cm-3 in volumetric limiting current density, which are 1.58 and 1.52 times as much as that of a MFC with an untreated carbon paper cathode, respectively. This best performance can be attributed to the cathode activated in the H2SO4 solution with the largest number of oxygen-containing functional groups, the largest electrochemical active surface area, strongest reduction of iron ions, and least resistance of the cathode.

为高效鉴定食用油脂加工厂污水处理过程的气味组成，采用感官检验以臭阈值量化不同处理工序污水的臭味浓度，并采用气相色谱-离子迁移谱法（GC-IMS）对其挥发性化合物进行分析，并对鉴定出的挥发性化合物进行指纹图谱和主成分分析。结果表明：污水经过处理臭阈值明显降低；GC-IMS鉴定出43种化合物，基本均为含氧有机物，包括酮类、醇类、醛类、酯类、酸类及其他类；总体上各处理工序污水挥发性物质总数和臭阈值的变化规律一致；各处理工序挥发性化合物存在一定差异。综上，GC-IMS是分析食用油脂加工厂污水处理过程气味变化的有效方法。 In order to effectively identify odorants in wastewater treatment process in edible oil plant, the odor concentration of wastewater from different treatment processes was quantified by the threshold odor number(TON) through sensory examination, and the volatile organic compounds (VOCs) were identified using gas chromatography-ion mobility spectrometry (GC-IMS) and analysed by fingerprint plot and principal component analysis. The results showed that the TON of wastewater was significantly reduced after treatment. Forty-three compounds were identified by GC-IMS, all of which were basically oxygen-containing organic compounds including ketones, alcohols, aldehydes, esters, acids and others. The change rule of TON of wastewater was overall consistent with volatile compounds among the treatment processes. There was a variation in VOCs′ overallcomposition among the treatment processes. In conclusion, the GC-IMS technique is an efficient method for analyzing the odor variation of wastewater treatment in edible oil plant.

The objective of this study was to investigate the effect of atractyloside, a promoter of the mitochondrial membrane permeability transition pore (MPTP), on mitochondrial membrane permeability, cristae structure, cytochrome c release and tenderness of postmortem beef and to explore the effect of injury on meat tenderness by releasing cytochrome c and activating caspases. The postmortem longissimus dorsi muscle of adult crossbred cattle was treated or not treated (control) with atractyloside, stored at 4 ℃ and evaluated for mitochondrial ultrastructure, membrane potential, the amount of cytochrome c released to the cytoplasm, cell apoptotic rate, caspase-3 and myofibrillary fragmentation index (MFI) after 0, 12, 24, 72, and 120 h. With postmortem aging time, the number of mitochondrial cristae decreased significantly, and swelling and rupture were observed. The mitochondrial membrane potential decreased significantly, and cytochrome c was released gradually. Starting from 72 h postmortem, the activity of caspase-3 and the apoptosis rate of myocytes increased, and so did MFI. Compared with the control group, atractyloside treatment induced mitochondrial damage by destroying mitochondrial cristae structure, reducing the membrane potential and causing cytochrome c release. In addition, the apoptosis of muscle cells and the fragmentation of myofibrils were accelerated by atractyloside. The opening of the MPTP significantly affected mitochondrial injury in beef after slaughter. Apart from increasing cell membrane permeability, atractyloside also significantly altered the structure of mitochondrial cristae. The internal and external mitochondrial membranes could synergistically regulate the release of cytochrome c, which in turn could affect postmortem tenderization of beef.

ObjectiveTo analyze the epidemic characteristics of foodborne disease outbreaks in Mengla County， Yunnan Province， so as to provide basis for formulating corresponding prevention and control measures.MethodsThe data of foodborne disease outbreaks in Mengla County， Yunnan Province from 2017 to 2021 in the national "foodborne disease outbreak monitoring system" were collected. The time， population， region， place， pathogenic factors and inducing links of the events were statistically analyzed.ResultsFrom 2017 to 2021， a total of 68 incidents were reported， including 526 cases and 5 deaths. The total incidence rate was 23.40% and the case fatality rate was 0.95%. The peak period was from May to July， with the largest number of reported events in July. The reporting areas were mainly Mengla Town （35.29%）， Guanlei Town （11.76%） and Mengpeng Town （10.29%）. The main place of the incident was family （76.47%）. The main pathogenic factors were plant toxins （79.41%）， mainly through the ingestion of wild mushrooms （68.52%）， improper processing of green beans （12.96%） and aconitum （9.26%）.ConclusionAccording to the epidemiological characteristics of Mengla County， we should focus on the public education of health knowledge in key areas and places， especially on the identification of wild mushrooms， to prevent accidental eating. At the same time， we should strengthen the monitoring and risk assessment of foodborne diseases， find potential risks as soon as possible， issue early warning and forecast in time， and constantly improve the clinical treatment ability of poisoned patients.

采用有机溶剂甲醇提取、HPLC同时分析芝麻油中芝麻素、芝麻林素和细辛素含量。为提高分析质量与准确性，优化甲醇提取溶剂用量和超声辅助提取的时间，并对检测方法进行方法学考察。结果表明：最佳提取条件为甲醇用量10 mL（芝麻油0.1 g），超声时间2 min;芝麻素、芝麻林素和细辛素线性范围分别为4～100 mg/L、4～100 mg/L和1～40 mg/L，线性关系良好，相关系数分别为0999 5、0.999 6和0.999 2；芝麻素、芝麻林素和细辛素的检出限分别为0.03、0.02 mg/g和0.02 mg/g，定量限分别为0.06、0.06 mg/g和0.04 mg/g，加标回收率分别为87.17%～92.59%、9271%～102.24%和95.66%～108.93%，加标回收率的相对标准偏差均小于5%，方法的稳定性、准确性和精密度均符合检测要求。该方法操作简单、耗时短(完成一次分析只需30 min)、成本低、稳定性高，能有效应用于芝麻油中3种木脂素组分的分析检测。The content of sesamin, sesamolin and asarinin in sesame oil was simultaneously analyzed by organic solvent methanol extraction and HPLC method. In order to improve the analysis quality and accuracy, the dosage of methanol extraction solvent and the time of ultrasound-assisted extraction were optimal, and the detection method was investigated. The results showed that the optimal extraction conditions were methanol dosage 10 mL（0.1 g sesame oil）, ultrasonic time 2 min. The sesamin, sesamolin and asarinin had good linearity within the ranges of 4-100 mg/L, 4-100 mg/L and 1-40 mg/L, respectively, and their correlation coefficients were 0.999 5, 0.999 6 and 0.999 2, respectively. The LOD of sesamin, sesamolin and asarinin were 0.03, 0.02 mg/g and 0.02 mg/g, respectively, and their LOQ were 0.06, 0.06 mg/g and 0.04 mg/g, respectively. The recoveries of sesamin, sesamolin and asarinin were 87.17%-92.59%, 92.71%-102.24% and 95.66%-10893%, respectively, with RSD all less than 5%. The stability, accuracy and precision of the method met the testing requirements. In conclusion, the method has advantages of simple operation, short time-consuming (only 30 min to complete an analysis), low cost, high stability, etc., and can be effectively applied to the analysis and detection of three lignan components in sesame oil.