Nondestructive measurement of water content and moisture migration of unsaturated red clays in South China

To reveal the moisture migration mechanism of the unsaturated red clays, which are sensitive to water content change and widely distributed in South China, and then rationally use them as a filling material for highway embankments, a method to measure the water content of red clay cylinders using X-ray computed tomography (CT) was proposed and verified. Then, studies on the moisture migrations in the red clays under the rainfall and ground water level were performed at different degrees of compaction. The results show that the relationship between dry density, water content, and CT value determined from X-ray CT tests can be used to nondestructively measure the water content of red clay cylinders at different migration time, which avoids the error reduced by the sample-to-sample variation. The rainfall, ground water level, and degree of compaction are factors that can significantly affect the moisture migration distance and migration rate. Some techniques, such as lowering groundwater table and increasing degree of compaction of the red clays, can be used to prevent or delay the moisture migration in highway embankments filled with red clays

Exploiting Category Names for Few-Shot Classification with Vision-Language Models

Vision-language foundation models pretrained on large-scale data provide a powerful tool for many visual understanding tasks. Notably, many vision-language models build two encoders (visual and textual) that can map two modalities into the same embedding space. As a result, the learned representations achieve good zero-shot performance on tasks like image classification. However, when there are only a few examples per category, the potential of large vision-language models is often underperformed, mainly due to the gap between a large number of parameters and a relatively small amount of training data. This paper shows that we can significantly improve the performance of few-shot classification by using the category names to initialize the classification head. With the proposed category name initialization method, our model obtains the state-of-the-art performance on a number of few-shot image classification benchmarks (e.g., 87.37% on ImageNet and 96.08% on Stanford Cars, both using five-shot learning)

Are mid-air dynamic gestures applicable to user identification?

Abstract Unlike the existing gesture related research predominantly focusing on gesture recognition (classification), this work explores the feasibility and the potential of mid-air dynamic gesture based user identification through presenting an efficient bidirectional GRU (Gated Recurrent Unit) network. From the perspective of the feature analysis from the Bi-GRU network used for different recognition tasks, we make a detailed investigation on the correlation and the difference between the gesture type features and the gesture user identity characteristics. During this process, two unsupervised feature representation methods – PCA and hash ITQ (Iterative Quantization) are fully used to perform feature reduction and feature binary coding. Experiments and analysis based on our dynamic gesture data set (60 individuals) exemplify the effectiveness of the proposed mid-air dynamic gesture based user identification approach and clearly reveal the relationship between the gesture type features and the gesture user identity characteristics

Plasmodium falciparumvar Gene Is Activated by Its Antisense Long Noncoding RNA

Plasmodium falciparum erythrocyte membrane protein 1, encoded by var gene, is an immunodominant antigen mediating immune evasion in humans. At a given time, only a single var gene is commonly expressed in one parasite. However, the regulation mechanism of var transcription remains largely unknown. In this study, we identified the antisense long non-coding RNA (aslncRNA) derived from var intron as an activation factor for the corresponding var gene. The exogenous artificial var aslncRNA transcribed by T7 RNA polymerase from episome can specifically activate the homologous var gene, and the exogenous aslncRNA activates transcription of both var mRNA and endogenous aslncRNA in a manner independent of the conserved intron sequence within the var gene family. Interestingly, the newly activated var gene and the previously dominant var gene then could be co-expressed in the same parasite nuclei, which suggests that the aslncRNA-mediated var gene activation could escape from the control of mutually exclusively expression of the var gene family. Together, our work shows that var aslncRNA is the activator responsible for var gene transcriptional regulation

Tetradentate Platinum(II) Emitters: Design Strategies, Photophysics, and OLED Applications

This chapter provides an overview of tetradentate platinum(II) emitters as a promising class of metal-organic phosphorescent dopants for organic light-emitting diodes (OLEDs). Tetradentate platinum(II) emitters showing blue, green, and red light emissions, which are essential for full color displays as well as white light emission, are reviewed and discussed in the context of molecular design and photophysical and electroluminescent properties. Emphasis is placed on the molecular structures, the nature of emissive excited states [including ligand-centered (LC), intra-ligand charge transfer (ILCT), metal-to-ligand charge transfer (MLCT), and excimeric and oligomeric metal-metal-to-ligand charge transfer (MMLCT)], the intermolecular interactions impacting photophysical attributes (e.g., emission energies, quantum yields, and decay times), and OLED device performances

A novel hybrid energy system combined with solar-road and soil-regenerator: Dynamic model and operational performance

This document is the Accepted Manuscript version, made available under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License CC BY NC-ND 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/). Under embargo until 26 November 2018. The final, definitive version of this article is available online at doi: https://doi.org/10.1016/j.enconman.2017.11.066.Solar roads are emergent and huge energy source in traffic domains. To improve the energy utilization efficiency of a solar road, a novel solar-road and soil-regenerator hybrid energy system in combination with conventional photovoltaic-thermal and soil heat storage technology was proposed. A mathematical model of the solar-road and soil-regenerator hybrid energy system was developed, validated, and applied to evaluate the thermal storage and power generation performance of the proposed system in cold regions. The results indicated that for critical thermal storage temperatures of 20, 30, and 40 °C, the proposed system decreased maximum photovoltaic cell temperatures by 24.09, 25.84, and 24.42 °C and increased electrical efficiencies by 6.85, 6.68, and 4.53%, respectively, compared with conventional solar roads. By storing heat in the soil and elevating soil temperatures, the proposed system also increased the average borehole wall temperatures by 2.93, 2.26, 1.87 °C. The proposed system produced overall energy efficiencies of 48.42, 55.47, and 66.58%, while conventional solar road efficiencies approximate 10.75%.Peer reviewe

Effects of various land utilization types on groundwater at different temporal scales: a case study of Huocheng plain, Xinjiang, China

Different land utilization types have unignorable impacts on adjacent aquifers, so studying the effects of varying land utilization types on groundwater balance and groundwater table in arid and semi-arid areas is crucial to facilitate the rational development of territorial space and groundwater resource management. This study investigated the relationship between land utilization type variations and groundwater dynamics from spatial and temporal scales in Huocheng plain, Xinjiang, China, via taking advantage of different land utilization maps provided by remote sensing techniques in 1990, 2000, and 2015. Based on the analysis of results, the findings can be summarized as follows. First, the cultivated and construction land has expanded significantly in the past 25 years. The migration of the regional center of cultivated land was insignificant, as it is still located almost in the center of the entire study area. However, the transfer span of the location center of construction land was more prominent, and its moving direction was mainly from south to northeast, directly affecting the groundwater balance state and groundwater table. Second, the total amount of groundwater storage exhibited a remarkable reduction, from a recharge in 1990 to a continuous discharge in 2000–2015, during which the total recharge and discharge had both continuously declined. Meanwhile, recharging and discharging elements were also changed profoundly as less groundwater recharges from ambient aqueous environments and more groundwater extraction. Thus, human activities were the fundamental driving terms causing the changes in groundwater sources. Third, the groundwater table gradually and continuously dropped from south to northeast in the study area over time. The drawdown of spatially averaged groundwater tables was positively correlated with construction and cultivated area extension. In addition, compared to the former literature, this study offers an alternative approach for groundwater protection and optimization of territorial space development and utilization in arid and semi-arid areas

Dynamics of Oxygen-Independent Photocleavage of Blebbistatin as a One-Photon Blue or Two-Photon Near-Infrared Light-Gated Hydroxyl Radical Photocage

Development of versatile, chemically tunable photocages for photoactivated chemotherapy (PACT) represents an excellent opportunity to address the technical drawbacks of conventional photodynamic therapy (PDT) whose oxygen-dependent nature renders it inadequate in certain therapy contexts such as hypoxic tumors. As an alternative to PDT, oxygen free mechanisms to generate cytotoxic reactive oxygen species (ROS) by visible light cleavable photocages are in demand. Here, we report the detailed mechanisms by which the small molecule blebbistatin acts as a one-photon blue light-gated or two-photon near-infrared light-gated photocage to directly release a hydroxyl radical (•OH) in the absence of oxygen. By using femtosecond transient absorption spectroscopy and chemoselective ROS fluorescent probes, we analyze the dynamics and fate of blebbistatin during photolysis under blue light. Water-dependent photochemistry reveals a critical process of water-assisted protonation and excited state intramolecular proton transfer (ESIPT) that drives the formation of short-lived intermediates, which surprisingly culminates in the release of •OH but not superoxide or singlet oxygen from blebbistatin. CASPT2//CASSCF calculations confirm that hydrogen bonding between water and blebbistatin underpins this process. We further determine that blue light enables blebbistatin to induce mitochondria-dependent apoptosis, an attribute conducive to PACT development. Our work demonstrates blebbistatin as a controllable photocage for •OH generation and provides insight into the potential development of novel PACT agents