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41.
为解决证据组合规则中一票否决和弱决策证据在低冲突情况下出现的反直观推理的现象,提出一种有效折扣证据源的冲突证据合成方法。首先根据证据的信任函数和似然函数求得证据间的相似度,然后求出证据之间的支持程度,并确定折扣因子,最后采用Dempster组合规则合成利用折扣因子修正后的证据源。数值算例分析结果表明,改进后的证据组合方法可以有效地处理证据冲突。 相似文献
42.
Saili Dharadhar Sagar Dhoble Vandana Patravale 《Drug development and industrial pharmacy》2019,45(2):188-201
Transdermal route has been explored for various agents due to its advantage of bypassing the first pass effect and sustained release of drug. Due to strong barrier properties of the skin, mainly stratum corneum (SC), the delivery of many therapeutic agents across the skin has become challenging. Few drugs with specific physicochemical properties (molecular weight <500?Da, adequate lipophilicity, and low melting point) can be effectively administered via transdermal route. However, delivery of hydrophilic drugs and macromolecular agents including peptides, DNA and small interfering RNA is challenging. Drug penetration through the SC may involve bypass or reversible disruption of SC layer by various means. Recently, the use of micron-scale needles has been proposed in increasing skin permeability and shown to dramatically increase permeation, especially for macromolecules. Microneedles (MNs) can penetrate through the SC layer of the skin into the viable epidermis, avoiding contact with nerve fibers and blood vessels that reside primarily in the dermal layer. This review summarizes the types of MNs and fabrication techniques of different types of MNs. The safety aspects of the materials used for fabrication have been discussed in detail. Biological applications and relevant phase III clinical trials are also highlighted. 相似文献
43.
Catherine O'Leary Yvonne de Kluizenaar Piet Jacobs Wouter Borsboom Ian Hall Benjamin Jones 《Indoor air》2019,29(3):423-438
There is growing awareness that indoor exposure to particulate matter with diameter ≤ 2.5 μm (PM2.5) is associated with an increased risk of adverse health effects. Cooking is a key indoor source of PM2.5 and an activity conducted daily in most homes. Population scale models can predict occupant exposures to PM2.5, but these predictions are sensitive to the emission rates used. Reported emission rates are highly variable and are typically for the cooking of single ingredients and not full meals. Accordingly, there is a need to assess PM2.5 emissions from the cooking of complete meals. Mean PM2.5 emission rates and source strengths were measured for four complete meals. Temporal PM2.5 concentrations and particle size distributions were recorded using an optical particle counter (OPC), and gravimetric sampling was used to determine calibration factors. Mean emission rates and source strengths varied between 0.54—3.7 mg/min and 15—68 mg, respectively, with 95% confidence. Using a cooker hood (apparent capture efficiency > 90%) and frying in non‐stick pans were found to significantly reduce emissions. OPC calibration factors varied between 1.5 and 5.0 showing that a single value cannot be used for all meals and that gravimetric sampling is necessary when measuring PM2.5 concentrations in kitchens. 相似文献
44.
Dr. Monica Varese Dr. Salvador Guardiola Dr. Jesús García Prof. Ernest Giralt 《Chembiochem : a European journal of chemical biology》2019,20(24):2981-2986
Our laboratory has recently identified two nanobodies (small antibodies produced by camelids)—Nb1 and Nb6—that bind efficiently to epithelial growth factor (EGF) and inhibit its ability to activate its receptor (EGFR). Because of the relevance of the EGF/EGFR axis as a target in oncology, these new nanobodies have promising therapeutic potential. This article, however, is focused on another feature of these nanobodies: their distinct thermodynamic signatures. Nb1 binds to EGF through an entropy-driven mechanism whereas Nb6 binds to this factor under enthalpic control. We discuss the advantages and disadvantages of each mechanism in the contexts of traditional medical chemistry (small-molecule drugs) and also of biological drugs. In this latter case, the implications in terms of selectivity are far from being clearly established and further experimental data are required. Their monomeric natures, high stability, and ease of recombinant production make nanobodies ideally suited for thermodynamic studies. Moreover, nanobodies, thanks to their simpler structures in comparison with conventional antibodies, might provide better understanding of the structural basis of the thermodynamic parameters of antigen recognition. 相似文献
45.
46.
Images with hazy scene suffer from low-contrast, which reduces the visible quality of the scene, thus making object detection a more challenging task. Low-contrast can result from foggy weather conditions during image acquisition. Dehazing is a process of removal of haze from the photography of a hazy scene. Single-image dehazing based on dark channel priors are well-known techniques in this field. However, the performance of such techniques is limited to priors or constraints. Moreover, this type of method fails when images have sky-region. So, a method is proposed, which can restore the visibility of hazy images. First, a hazy image is divided into blocks of size 32 × 32, then the score of each block is calculated to select a block having the highest score. Atmospheric light is calculated from the selected block. A new color channel is considered to remove atmospheric scattering, obtained channel value and atmospheric light are then used to calculate the transmission map in the second step. Third, radiance is computed using a transmission map and atmospheric light. The illumination scaling factor is adopted to enhance the quality of a dehazed image in the final step. Experiments are performed on six datasets namely, I-HAZE, O-HAZE, BSDS500, FRIDA, RESIDE dataset and natural images from Google. The proposed method is compared against 11 state-of-the-art methods. The performance is analyzed using fourteen quantitative evaluation metrics. All the results demonstrate that the proposed method outperforms 11 state-of-the-art methods in most of the cases. 相似文献
47.
Bin Feng Xin Jiang Guisheng Zou Wengan Wang Tianming Sun Heng Yang Guanlei Zhao Mingye Dong Yu Xiao Hongwei Zhu Lei Liu 《Advanced functional materials》2021,31(29):2102359
The realization of liquid metal-based wearable systems will be a milestone toward high-performance, integrated electronic skin. However, despite the revolutionary progress achieved in many other components of electronic skin, liquid metal-based flexible sensors still suffer from poor sensitivity due to the insufficient resistance change of liquid metal to deformation. Herein, a nacre-inspired architecture composed of a biphasic pattern (liquid metal with Cr/Cu underlayer) as “bricks” and strain-sensitive Ag film as “mortar” is developed, which breaks the long-standing sensitivity bottleneck of liquid metal-based electronic skin. With 2 orders of magnitude of sensitivity amplification while maintaining wide (>85%) working range, for the first time, liquid metal-based strain sensors rival the state-of-art counterparts. This liquid metal composite features spatially regulated cracking behavior. On the one hand, hard Cr cells locally modulate the strain distribution, which avoids premature cut-through cracks and prolongs the defect propagation in the adjacent Ag film. On the other hand, the separated liquid metal cells prevent unfavorable continuous liquid-metal paths and create crack-free regions during strain. Demonstrated in diverse scenarios, the proposed design concept may spark more applications of ultrasensitive liquid metal-based electronic skins, and reveals a pathway for sensor development via crack engineering. 相似文献
48.
当前,安全生产事故频发,造成重大人员伤亡和财产损失,成为国家安全生产亟需解决的问题,按照新时期新要求,加强自然资源领域安全生产管理尤为重要。本文重点围绕自然资源领域涉及的土地资源、矿产资源、海洋资源以及测绘行业和地勘行业,通过调研及专家座谈,分析了我国自然资源领域安全生产管理的现状,存在的问题和产生的原因;结合新时期自然资源管理实际,以及地方和其他部门典型经验,从制度机制、标准化、信息化、人才培养等角度提出了加强我国自然资源领域安全生产管理的措施和建议,以供参考。 相似文献
49.
Dr. Tomasz Ratajczyk Prof. Dr. Gerd Buntkowsky Dr. Torsten Gutmann Dr. Bartłomiej Fedorczyk Dr. Adam Mames Dr. Mariusz Pietrzak Zuzanna Puzio Piotr Grzegorz Szkudlarek 《Chembiochem : a European journal of chemical biology》2021,22(5):855-860
The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the epidermal growth factor receptor (EGFR), has been successfully employed as a substrate in magnetic resonance signal amplification by reversible exchange (SABRE) experiments. It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes molecular complex. The interaction between PyFALGEA:IMes and H2 results in a ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex is labile, which is an essential condition for successful hyperpolarization by SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading to significant enhancement of the 1H NMR signals of PyFALGEA. Different iridium catalysts and peptides are inspected to discuss the influence of their molecular structures on the efficiency of hyperpolarization. It is observed that PyFALGEA oligopeptide hyperpolarization is more efficient when an iridium catalyst with a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE complex, which hampers hyperpolarization with IMes. Finally, a single-scan 1H NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR lines in the hydride region, which can be treated as a fingerprint of this important oligopeptide. 相似文献
50.
Thin and lightweight organic light-emitting diodes (OLEDs) are promising candidates for next-generation rollable displays; they offer numerous advantages, such as scalable manufacturing, high color contrast ratio, flexibility, and wide viewing angle. Despite the numerous merits of OLEDs, the insufficient lifetime and stability of blue OLEDs remain unresolved, thereby necessitating a feedback strategy for lifetime extension. Herein, we propose a simple yet effective methodology to determine the contact resistance (RCT) and characteristic trap energy (ET) of OLEDs simultaneously in the trapped-charge-limited-conduction regime, where electroluminescence occurs primarily. To validate our approach, the extracted RCT and ET values are directly compared with each other by connecting a commercial resistor (RC) to a blue OLED in series. The percent errors discovered in RC and ET are less than 7% and 4%, demonstrating the high feasibility and accuracy of our approach. We further employ this method to study the degradation mechanism of a blue OLED by presenting the electrical stress time- and cycle-dependent RCT, ET, ideality factor, and turn-on voltage, revealing different degradation patterns of the metal-to-transport layer interface and emission layer, respectively. Our results provide better insights into the electrical parameter extraction method and electrical current degradation mechanism in blue OLEDs. 相似文献