Self-assisted wound healing using piezoelectric and triboelectric nanogenerators

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固相萃取-超高效液相色谱-串联质谱法同时检测食品中的烟酰胺单核苷酸α、β异构体和烟酰胺腺嘌呤二核苷酸

目的 建立固相萃取-超高效液相色谱-串联质谱法同时测定食品中烟酰胺单核苷酸(nicotinamide mononucleotide, NMN) α、β异构体和烟酰胺腺嘌呤二核苷酸(nicotinamide adenine dinucleotide, NAD⁺)含量的方法。方法 样品经5%甲醇水溶液超声提取, HLB固相萃取柱和混合型阴离子交换固相萃取柱分别净化,采用Waters ACQUITY UPLC?HSS T色谱柱进行分离,流动相为5 mmol/L乙酸铵含0.1%(V/V)甲酸水-甲醇,梯度洗脱;流速0.2 mL/min;柱温30℃;多反应监测(multiple reaction monitoring, MRM)模式定量分析,定量离子对NMN为m/z 335.0/123.0、NAD⁺为m/z 662.0/540.0。结果 在最优条件下, α-NMN和β-NMN两种异构体的分离度为5.56。该方法中α-NMN、β-NMN和NAD⁺均在10～1000 ng/mL范围内线性良好,相关系数分别为0.9999, 0.9998...     

具有动态调节功能的Fisherface方法

高维、小样本数据的识别问题,始终是模式识别领域的热点和难点问题。由于训练样本数量很少,当以样本的协方差矩阵作为模式协方差矩阵的估计时,会产生较大的偏差。这是造成模式分类错误的主要原因。本文在详细论述Fisherface方法的基础上,提出了具有动态调节功能的Fisherface（DA-Fisherface）方法。该方法利用测试样本完成了对样本协方差矩阵的动态调节,减小了因样本数目很少所造成的偏差,从而实现了对Fisher鉴别矢量集的优化。最后,在ORL人脸库上的实验结果表明,该方法的模式分类正确率比Fisherface方法有显著提高。     

SHUM-UCOS:基于统一多任务模型可重构系统的实时操作系统

在分析软硬件任务本质区别的基础上,提出并实现了一种基于统一多任务模型的实时操作系统,称为SHUM-UCOS,它能够跟踪和管理可重配置资源的使用,通过硬件任务预配置技术,提高了资源利用率和任务并行性,定义了两种标准硬件线程接口,对总线型和星型通信拓扑结构提供支持,Rhealstone Benchmark测试和实际应用都表明,SHUM-UCOS能够在提升系统性能的同时,有效缩减从软件实现到硬件实现的迁移时间。     

Event vertex and time reconstruction in large-volume liquid scintillator detectors

Large-volume liquid scintillator detectors with ultra-low background levels have been widely used to study neutrino physics and search for dark matter. Event ve...     

Identification of Entry Inhibitors against Delta and Omicron Variants of SARS-CoV-2

Entry inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are urgently needed to control the outbreak of coronavirus disease 2019 (COVID-19). This study developed a robust and straightforward assay that detected the molecular interaction between the receptor-binding domain (RBD) of viral spike protein and the angiotensin-converting enzyme 2 (ACE2) receptor in just 10 min. A drug library of 1068 approved compounds was used to screen for SARS-CoV2 entry inhibition, and 9 active drugs were identified as specific pseudovirus entry inhibitors. A plaque reduction neutralization test using authentic SARS-CoV-2 virus in Vero E6 cells confirmed that 2 of these drugs (Etravirine and Dolutegravir) significantly inhibited the infection of SARS-CoV-2. With molecular docking, we showed that both Etravirine and Dolutegravir are preferentially bound to primary ACE2-interacting residues on the RBD domain, implying that these two drug blocks may prohibit the viral attachment of SARS-CoV-2. We compared the neutralizing activities of these entry inhibitors against different pseudoviruses carrying spike proteins from alpha, beta, gamma, and delta variants. Both Etravirine and Dolutegravir showed similar neutralizing activities against different variants, with EC50 values between 4.5 to 5.8 nM for Etravirine and 10.2 to 22.9 nM for Dolutegravir. These data implied that Etravirine and Dolutegravir may serve as general spike inhibitors against dominant viral variants of SARS-CoV-2.     

Reported Use of Reduced-sugar Foods and Beverages Reflect High-quality Diets

ABSTRACT: The purpose of this study was to determine differences in nutrient and energy intakes and in quantity of food eaten, and to compare the knowledge, attitudes, and practices of users of reduced-sugars foods and beverages with those who use only the full sugar versions of the same products. Records for adults (≥ 20 y old) responding to the 1994–1996 Continuing Survey of Food Intakes by Individuals (CSFII) and the Diet Health and Knowledge Survey were used. CSFII food lists were scanned for both full and reduced-sugar versions of yogurt, cocoa, and other milk beverages, frozen and gelatin desserts, puddings, breads, cookies, cakes, fruit drinks, carbonated and noncarbonated drinks, confectionary products, and sweeteners. Recalls were sorted for those reporting use of only full sugar (FS) products and those reporting mixed use of full sugar and reduced-sugar (RS) versions. Comparisons were made between demographic characteristics, body mass index, food group servings, food intake amounts, and nutrient densities. When compared with FS users, RS users consistently reported significantly higher intakes of fruit, lower intakes of discretionary fat and added sugars, and equal or lower intakes of other foods (in gram amounts), except for greater intake of yogurt and frozen and gelatin desserts. RS users tended to report similar or higher micronutrient intakes compared with FS users. After adjusting for energy intake, significantly higher micronutrient intakes were found for both males and females consuming RS foods and beverages (13 and 15 of 17 nutrients, respectively).     

Issues Related to the Use of Blood in Food and Animal Feed

Blood has traditionally been used as a high protein ingredient in both human food and animal feed, with resulting economic, environmental and nutritional benefits. However, potentially serious health and safety issues related to blood consumption, particularly the risk of pathogenic or harmful metabolic materials, the infectivity of prion diseases, and the presence of identified allergens such as bovine serum albumin (BSA), are causing many consumers to shy away from any product containing either animal blood or ingredients derived from animal blood. Thus, despite the significant volumes of blood produced by slaughterhouses, blood is currently underutilized as a food ingredient. This article reviews the use of animal blood as an ingredient in food intended for human consumption or for animal feed and discusses the related consumer concerns.     

Effect of high-voltage electrostatic field on quality of carrot juice during refrigeration

In the present study, carrot juice was used as the experimental material and stored in a 100 kV/m high-voltage electrostatic field (HVEF; E-group) which was used as a freshness-retention system. The changes in the biological properties were investigated relative to those juices which were stored in a common refrigerator (R-group) and controlled at the same temperature (4 °C). The results showed that the extent of color difference (ΔE), amount of total phenolics, tannins, and total plate counts of carrot juice were increased during the storage period, whereas the turbidity and amount of total carotenoids decreased under all treatment conditions. These factors remained relatively constant during storage in the E-group, whereas a significant difference (p < 0.05) was observed in the R-group. The HVEF treatment yielded better physicochemical properties and prolonged the shelf-life of the carrot juice. The application of HVEF at low temperature has the potential of imparting freshness and a high nutritional value to the products.