Unifying Charge Generation,Recombination, and Extraction in Low‐Offset Non‐Fullerene Acceptor Organic Solar Cells

Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor π? π interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.     

绵马贯众多糖超声提取工艺优化及抗氧化活性分析

绵马贯众是中国传统常用中药,本研究以温度、时间、超声功率、液料比为影响因子,多糖得率为评价指标,通过响应面法优化超声辅助提取绵马贯众多糖的工艺条件,同时测定其基本理化性质及抗氧化活性。研究结果表明,绵马贯众多糖的最佳提取工艺条件为:温度64℃、时间60 min、超声功率210 W、液料比27 mL/g。此时多糖得率为9.57%,与预测值接近。理化性质分析表明绵马贯众多糖为含少量蛋白的酸性多糖。体外抗氧化研究表明绵马贯众多糖具有很强的DPPH自由基清除活性,IC50值为0.29 mg/mL;较好的羟基自由基清除活性,其IC50值为1.10 mg/mL;对DNA的氧化损伤有显著的保护作用。绵马贯众多糖可以作为一种潜在的抗氧化剂应用于食品和化妆品等领域。     

Synergized subcritical-ultrasound-assisted aqueous two-phase extraction,purification, and characterization of Lentinus edodes polysaccharides

The effect of a synergized two-step subcritical water extraction (SWE) and simultaneous multi-frequency ultrasound-assisted alcohol/salt aqueous two-phase extraction (MFu-AATPE) on the yield, physicochemical, structural characteristics, and antioxidant activities of Lentinus edodes polysaccharides (LEPs) was investigated. Crude LEP extracted under subcritical extraction (31.14%) was purified using dual and triple frequency ultrasound-assisted aqueous two-phase systems giving a yield of 94.57% and 97% respectively. Compared with the dual-frequency sonication (20/40 kHz), the triple frequency sonication (20/40/60 kHz) gave maximum yield and improved the desalination rate by 33.6%. Congo red analysis revealed triple helix structures. Gas Chromatography analysis showed the existence of mannose, glucose, arabinose, xylose, and galactose whilst spectral similarities were observed through Fourier Transform Infrared Spectroscopy. The average molecular weight (M_w) was 83.6170 Da, 2384 Da and 2387 Da for control, dual and triple frequency samples respectively. Ultrasound treated polysaccharides displayed stronger antioxidant activities against the 2.2-diphenyl;-1 picrylhydrazyl (DPPH), 2, 2ʹ-azino-bis 3-ethylbenzothiazoline-6 sulfonic acid (ABTS) and hydroxyl radicals, thus demonstrating their potency in reducing oxidation. However, the microstructure of the triple frequency treated sample was altered compared to the dual-frequency sample. Therefore, this study demonstrated the efficacy of SWE in crude LEPs extraction and illustrated MFu-AATPE as an efficient technique that selectively isolates polysaccharides and enhances extraction efficiencies.     

More than skin and bones: Comparing extraction methods and alternative sources of DNA from avian museum specimens

Next‐generation sequencing has greatly expanded the utility and value of museum collections by revealing specimens as genomic resources. As the field of museum genomics grows, so does the need for extraction methods that maximize DNA yields. For avian museum specimens, the established method of extracting DNA from toe pads works well for most specimens. However, for some specimens, especially those of birds that are very small or very large, toe pads can be a poor source of DNA. In this study, we apply two DNA extraction methods (phenol–chloroform and silica column) to three different sources of DNA (toe pad, skin punch and bone) from 10 historical avian museum specimens. We show that a modified phenol–chloroform protocol yielded significantly more DNA than a silica column protocol (e.g., Qiagen DNeasy Blood & Tissue Kit) across all tissue types. However, extractions using the silica column protocol contained longer fragments on average than those using the phenol–chloroform protocol, probably as a result of loss of small fragments through the silica column. While toe pads yielded more DNA than skin punches and bone fragments, skin punches proved to be a reliable alternative source of DNA and might be especially appealing when toe pad extractions are impractical. Overall, we found that historical bird museum specimens contain substantial amounts of DNA for genomic studies under most extraction scenarios, but that a phenol–chloroform protocol consistently provides the high quantities of DNA required for most current genomic protocols.     

Development of a potent and orally active activator of adenosine monophosphate-activated protein kinase (AMPK), ASP4132, as a clinical candidate for the treatment of human cancer

Adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a key role in maintaining cellular metabolism. AMP or adenosine diphosphate (ADP) levels rise during metabolic stress, such as during nutrient starvation, hypoxia and muscle contraction, and bind to AMPK to induce activity. Recently, activation of AMPK has been considered an attractive therapeutic strategy in the field of human oncology. Structural optimization of lead compound 2, a new type of AMPK activator with potent AMPK activation activity and attractive selective growth inhibition against human cancer cells, improved aqueous solubility, metabolic stability and animal pharmacokinetics (PK) and culminated in the identification of (5-{1-[(6-methoxypyridin-3-yl)methyl]piperidin-4-yl}-1H-benzimidazol-2-yl)(4-{[4-(trifluoromethyl)phenyl]methyl}piperazin-1-yl)methanone ditosylate, ASP4132 (28). Studies on ASP4132 had advanced to clinical trials for the treatment of cancer.     

铜藻岩藻黄素提取及纯化工艺研究

为了对岩藻黄素的提取、纯化进行系统研究,进而为高纯度岩藻黄素的工业化生产提供研究基础,筛选了适用于提取铜藻（Sargassum horneri）鲜藻中岩藻黄素的有机溶剂,并通过单因素实验和正交实验确定了最佳的提取溶剂浓度、提取温度、提取时间、料液比等工艺参数。随后采用硅胶柱层析法进行纯化,并通过单因素实验确定了最佳的硅胶柱床高度、上样量和洗脱流速。最后采用制备液相法对经层析纯化的岩藻黄素进一步纯化。结果表明,有机溶剂萃取的最佳工艺条件为：甲醇浓度90%,提取温度50 ℃,提取时间1 h,料液比1∶10,此条件下岩藻黄素提取率达到(0.258 9±0.003 6) mg·g-1鲜重（FW）［(1.078 8±0.015 0) mg·g-1干重（DW）］。硅胶柱层析的最佳工艺条件为：硅胶柱床高度10 cm,上样量6 g,洗脱流速10 mL·min-1,此条件下岩藻黄素得率为0.176 5 mg·g-1FW（0.735 3 mg·g-1 DW）,纯度为87.01%±0.88%。经制备液相进一步纯化后,岩藻黄素得率为0.127 1 mg·g-1 FW（0.529 4 mg·g-1 DW）,纯度为99.27%±0.22%。研究所用工艺简单,岩藻黄素得率高,为高纯度岩藻黄素的制备提供了实验基础。     

Myocardial Infarction Detection and Localization Using Optimal Features Based Lead Specific Approach

ObjectivesObjective of this paper is to present a reliable and accurate technique for Myocardial Infarction (MI) detection and localization.Material and methodsStationary wavelet transform has been used to decompose the ECG signal. Energy, entropy and slope based features were extracted at specific wavelet bands from selected lead of ECG. k-Nearest Neighbors (kNN) with Mahalanobis distance function has been used for classification. Sensitivity (Se), specificity (Sp), positive predictivity (+P), accuracy (Acc), and area under the receiver operating characteristics curve (AUC) analyzed over 200 subjects (52 health control, 148 with MI) from Physikalisch-Technische Bundesanstalt (PTB) database has been used for performance analysis. To handle the imbalanced data adaptive synthetic (ADASYN) sampling approach has been adopted.ResultsFor detection of MI, the proposed technique has shown an AUC = 0.99, Se = 98.62%, Sp = 99.40%, PPR = 99.41% and Acc = 99.00% using 12 top ranked features, extracted from multiple leads of ECG and AUC = 0.99, Se = 98.34%, Sp = 99.77%, PPR = 99.77% and Acc = 99.05% using 12 features extracted from a single ECG lead (i.e. lead V5). For localization of MI, the proposed technique has an AUC = 0.99, Se = 98.78%, Sp = 99.86%, PPR = 98.80%, and Acc = 99.76% using 5 top ranked features from multiple leads of ECG and AUC = 0.98, Se = 96.47%, Sp = 99.60%, PPR = 96.49% and Acc = 99.28% using 8 features extracted from a single ECG lead (i.e. lead V3).ConclusionThus for MI detection and localization, the proposed technique is independent of time-domain ECG fiducial markers and can work using specific leads of ECG.