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With the rise of short videos as a form of social media, knowledge short videos cater to people's need for fragmented learning in a fast-paced life and have become a new way of informal learning. The current state of this kind of short videos and the role these videos play in fragmented learning have not been discussed in depth. The study chooses the short video platform TikTok as an example and uses the Lasswell’s 5W model to analyze the status and the transmission effect of this kind of videos. The results show that the short-form video platforms are important contributors to the dissemination of knowledge-based content, but the authenticity and quality of knowledge short videos need to be improved. In this regard, the short-video platforms should establish interrogative mechanisms for content, encourage user’s learning behavior and try to build online learning communities to promote the knowledge transmission.

The main methods currently used to detect illegally added chemicals in cosmetics include thin-layer chromatography, high performance liquid chromatography (HPLC), gas chromatography (GC), and liquid chromatography-mass spectrometry (LC-MS). Compared with other analytical techniques, these methods have the advantages of high sensitivity, specificity, and accuracy, all of which are required in practical detection work. However, they also present a number of limitations, such as long analysis times and requirements for skilled operators and strictly controlled laboratory environments. Supervision, a growing trend in market surveillance, requires rapid and effective methods to screen illegally added chemicals. The suspected samples are sealed for some time and then sent to the laboratory for further testing. Ion mobility spectrometry (IMS) is a new type of trace gas separation technology that was developed in recent years. The principle behind IMS is the separation and characterization of chemical species based on differences in the migration speed of their gas-phase ions under an electric field. As this technology has the advantages of miniaturization, easy operation, and quick responses, it is widely used in food and drug quality testing, as well as other related fields. However, it is rarely used in cosmetic detection, likely because the cosmetics matrix is highly complex, which can interfere with ion determination. Thus, optimizing the pretreatment process of cosmetics for IMS is important. In this work, solid-phase extraction (SPE) is combined with IMS to establish a method for the rapid screening of 14 antibacterial drugs in anti-acne cosmetics. The IMS detection parameters, sample extraction conditions, and SPE clean-up conditions (SPE column, type of leachate, type and volume of eluent) were studied and optimized in detail. The sample was extracted with 80%(v/v) acetonitrile aqueous solution (containing 0.2% (mass fraction) trichloroacetic acid), loaded onto an activated Oasis

Background: Handgrip strength (HGS) and the appendicular lean mass index (ALMI) are important determinants of sarcopenia. Muscle quality (MQ) is a measure of muscle strength relative to muscle mass. We examined trends in handgrip strength, the appendicular lean mass index, and analyzed their relationship with age, anthropometry, and body composition in a sample of participants in the United States (US). Methods: This cross-sectional study analyzed data from 14,741 US males (49.7%) and females (50.3%) 6–80 years old who responded to the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2014. Dual X-ray absorptiometry was used to measure appendicular skeletal muscle mass. HGS was evaluated using the Takei Digital Grip Strength Dynamometer. Smoothed normative curves for HGS and the ALMI were constructed using a generalized additive model. Multiple regression analyses were used to examine associations of HGS and the ALMI with age, nutrition-related factors, physical activity, and body composition. Results: Mean HGS and the ALMI declined with advancing age. While mean HGS increased with the ALMI, it decreased with the fat mass index. HGS increased in males with an increase in body mass index, energy intake, the ALMI, and vitamins; however, HGS in females increased with albumin, but it had a negative association with the fat mass index and age, but not with increasing adiposity. Conclusions: HGS and the ALMI change with age: HGS increases with age, then stabilizes and declines; the ALMI increases with age, then stabilizes. In addition, we provide evidence for the effect of anthropometry, nutrition, physical activity, and body composition on HGS and the ALMI in US population.

Litsea cubeba Pers., a dioecious species, is an important tree species for the bioenergy industry with great potential for lead (Pb)-polluted soil phytoremediation. However, the sex-specific morphological and physiological characteristics of L. cubeba under Pb stress remain largely unknown. In this study, L. cubeba was used as a study model to identify sex differences in leaf traits, chlorophyll, photosynthetic gas parameters, chlorophyll fluorescence, Pb subcellular distribution, and photosynthesis-related nutrient contents in chloroplasts and cell nuclei under three different Pb concentrations [0 (CK), 1 (P1), 2 (P2), and 3 (P3) mmol/kg]. The results indicate that Pb stress significantly decreases photosynthetic leaf pigments in both sexes, mainly caused by changes in Ca, Mg, and Mn contents. Furthermore, L. cubeba male plants exhibited greater adaptability to Pb stress by enlarging their leaf area, enhancing photosynthesis and excess light energy in the form of heat dissipation when compared to female plants. Notably, we observed that more Pb reached the organelle fraction and damaged chloroplasts and mitochondria in female leaves under high-level Pb treatments compared to those of the opposite sex. Transcriptome analysis demonstrated that Pb stress could significantly up-regulate more genes involved in photosynthetic antenna proteins and photosynthesis pathways in male leaves than in female leaves. Taken together, L. cubeba male plants are clearly more resistant to Pb toxicity than female plants—at least under the described Pb treatments—which is most likely due to differences in Pb allocation. This research offers a theoretical foundation for the utilization of male and female L. cubeba as suitable plants for the remediation of Pb-polluted soil.

With the growing emphasis on medical testing, people are seeking more technologies to detect indexes of the human body quickly and at a low cost. The electrochemical biosensors became a research hotspot due to their excellent properties. In this study, dicopper hydroxide phosphate (Cu2(OH)PO4) was incorporated in resin, and the resin sheets were prepared by digital light processing (DLP). The copper base points were activated on the resin sheet surface by Nd: YAG laser and then covered by the electroless copper plating and the electroless silver plating. The laser could effectively activate copper base points on the resin surface. Furthermore, silver electrodes on the detection chips could distinguish glucose solutions of different concentrations well. Finally, a novel detection kit with a three-electrode chip was designed for rapid health testing at home or in medical institutions in the future.

The data from event cameras not only portray contours of moving objects but also contain motion information inherently. Herein, motion information can be used in event‐based and frame‐based object trackers to ease the challenges of occluded objects and data association, respectively. In the event‐based tracker, events within a short interval are accumulated. Within the interval, the histogram of local time measurements (or ‘motion histogram’) is proposed as the feature to describe the target and candidate regions. Then the mean‐shift tracking approach is used by shifting the tracker towards similarity maximisation on motion histograms between target and candidate regions. As for the frame‐based tracker, given the assumption that a single object moves at a constant velocity on the image plane, the distribution of local timestamps is modelled, followed by which object‐level velocities are obtained from parameter estimation. We then build a Kalman‐based ensemble, in which object‐level velocities are deemed as an additional measurement on top of object detection results. Experiments have been conducted to measure the performance of proposed trackers based on our self‐collected data. Thanks to the assistance from motion information, the event‐based tracker successfully differentiates partially overlapped objects with distinct motion profiles; The inter‐frame tracker avoids data association failure on fast‐moving objects and leads to fast convergence on object velocity estimation.

Mitochondrial permeability transition pore (mPTP) is an important regulator in cell apoptosis and necrosis. However, its role in hepatic steatosis, especially its electrophysiological properties transformation remains elusive. Herein, using diabetes mice, we investigated the role of mPTP in hepatic steatosis triggered by diabetes and the mechanisms involved. We found that hepatic steatosis altered mitochondrial morphology, generating mega mitochondria, mitochondria swelling, calcein fluorescence quenching and mitochondrial membrane potential depolarization. At the same time, we confirmed an augmented mPTP opening with patch clamping in liver mitoplasts in db/db mice and a similar transformation with arachidonic acid (AA) simulating liquid deposition. We also found mPTP opening was significantly attenuated in wt mice after removing mitochondrial matrix, while that in db/db mice remained active. In addition, we observed that AA could directly activate mPTP in inside-out mode, independent of matrix calcium. In conclusion, we for the first time provided a physiological evidence of mPTP opening in lipid deposition, which could be directly induced by AA without Ca2+ and can be inhibited by cyclosporine A. As a result, it led to mitochondria morphology and function transformation. This might provide insights into potential therapeutic target for future treatment of mitochondrial liver disease.

Watershed and catchment area-based water quality management are important methods for comprehensive management of rivers and lakes. The impacts of land use/land cover (LULC) on river water quality vary with spatial scales, such as watersheds, catchments, and riparian zones. Achieving an effective spatial scale relationship between LULC and water quality, determining priority management areas, and reaching sustainable development of large estuarine deltas remain problematic. In this study, buffering analysis on the water quality data of the Yangtze River Estuary from 2009 to 2018 was conducted based on LULC, and the priority management areas of the basin were identified. Also, we infer that future river restoration or management efforts should focus on priority management area construction of a 1500 m riparian zone and a 150 km reach zone. Conclusively, establishing a priority management area within the effective buffer zone is key to watershed water quality management.

Phosphatase and tensin homolog deleted on chromosome ten (PTEN) is widely known as a tumor suppressor gene. It is located on chromosome 10q23 with 200 kb, and has dual activity of both protein and lipid phosphatase. In addition, as a targeted gene in multiple pathways, PTEN has a variety of physiological activities, such as those regulating the cell cycle, inducing cell apoptosis, and inhibiting cell invasion, etc. The PTEN gene have been identified in many kinds of cancers due to its mutations, deletions and inactivation, such as lung cancer, liver cancer, and breast cancer, and they are closely connected with the genesis and progression of cancers. To a large extent, the tumor suppressive function of PTEN is realized through its inhibition of the PI3K/AKT signaling pathway which controls cells apoptosis and development. In addition, PTEN loss has been associated with the prognosis of many cancers, such as lung cancer, liver cancer, and breast cancer. PTEN gene is related to many cancers and their pathological development. On the basis of a large number of related studies, this study describes in detail the structure, regulation, function and classical signal pathways of PTEN, as well as the relationship between various tumors related to PTEN. In addition, some drug studies targeting PTEN/PI3K/AKT/mTOR are also introduced in order to provide some directions for experimental research and clinical treatment of tumors.

The purpose of this paper is to understand the sources of potentially toxic elements (PTE) and provide some suggestions to control PTE pollution. For this purpose, data from 30 monitoring stations for 2009-2018 were used to assess the PTE concentrations of Hg, Cu, Pb, Cd, Zn, and As in the Yangtze River Estuary. The PTE concentrations varied significantly (P < 0.05) by one-way ANOVA in the ranges of 0.002-0.224 (Hg, 0.043 ± 0.032), 0-9.700 (Cu, 1.600 ± 1.000), 0-3.900 (Pb, 1.000 ± 0.700), 0.002-0.370 (Cd, 0.050 ± 1.000), 0.100-85.000 (Zn, 14.000 ± 13.000), and 0.998-3.290 μg/L (As, 1.857 ± 0.455). Generally, the PTE concentrations decreased from year to year and were consistently satisfied the "grade-one seawater" quality standard after 2014. The concentrations of Cu, Cd, Zn, and As decreased as far from inshore, while increased closer to land in the estuary. Concentrations of Pb and Hg showed differences because of local industrial and aquacultural activities. This study identified three clusters and two PTE sources and provided some constructive suggestions for pollution control in PTE.

Theory of self-organization, i.e., scale-dependent feedback (SDF), has been widely used to explain mechanisms of spatial patterns in different ecosystems. Studies have demonstrated that self-organization is one of the mechanisms through which ecosystem resilience is maintained. However, the application of SDF in real ecological restoration practices is a challenge due to the lack of a controlled experimental validation. In the present study, multiple scales of vegetation patches were constructed along an elevation gradient in the saltmarsh ecosystem on Nanhui coasts and were investigated to verify if there was an effect of SDF. Results of the density-variation curves analyses revealed that most constructed self-organized patches could survive and an optimal curve was found of which the density-dependent feedback was proven through fitting with the asymptotic regression model. The large vegetation patches exhibited considerable increases in density when compared to the small vegetation patches, which occurred in challenging environments, i.e., on the verges of elevation thresholds, and with a tendency to shrink. Analyses using one-way ANOVA revealed that there was an optimal patch scale and elevation in the study area, i.e., 1 m × 1 m scale and 3.2 m, respectively. Optimal scale and elevation provide a comprehensively explanations of SDF, although with the positive effects gradually decreased along the distance away from the optimal condition. The present study provides novel insights on applying the theory of SDF in facilitating the restoration process of coastal saltmarshes.

Recent years witness an ever-increasing research interest in the study of securing the Networked Control Systems due mainly to the trend of integrating the advanced communication technical into the traditional control system. As a result, the control system becomes prone to the cyber attacks and a number of serious security incidents of the industrial control system are reported. Firstly, we recall the most recent occurred security incident of control system, and various types of control-system-oriented cyber attacks are introduced. Then, a wealth of resilient control methodologies are presented which aim to securing the control system. Finally, the applications of the resilient control method to the power system is introduced.

PbSe is a simple binary compound that has been studied extensively for use as a promising moderate-temperature thermoelectric material. In this Letter, we report the observation of the light-induced transverse thermoelectric (TTE) effect in c-axis inclined PbSe thin films that were grown epitaxially on c-axis miscut SrTiO3 single crystal substrates using the pulsed laser deposition technique. Because of the anisotropic Seebeck coefficient of these inclined PbSe thin films, high TTE voltage signals were detected when the film surfaces were irradiated using various different continuous-wave lasers with wavelengths ranging from the ultraviolet (360 nm) to the far infrared (10.6 μm). In addition, the amplitudes of the output voltage signals showed good linear dependence on both the radiation power density and the film inclination angle. The results above demonstrate the potential of PbSe for self-powered ultra-broadband light detection applications.

The recent development of single-molecule sensors (SMS), which detect individual targets one at a time, allows determination of ultra-low concentrations of structurally similar compounds from a complex matrix. Protein nanopores are one of the earliest methods able to resolve the signal from a single molecule, and have already been successfully employed in commercial DNA sequencers. The protein nanopore based SMS, however, remains challenging, largely because the quantitative single-molecule analysis requires recording a sufficient number of signals for statistical significance within a reasonable time frame, thus restricting the lower limit of detection. This review aims to critically evaluate the strategies developed in this field over the last two decades. The measurement principle of nanopore SMS is first elucidated, followed by a systematic examination of the eight common protein pores, and a comprehensive assessment of the major types of sensing applications. A particular emphasis is placed on the intrinsic relationship between the size and charge of protein nanopores and their sensing capabilities for different kinds of analytes. Innovative approaches to lift the performance of nanopore SMS are also analyzed in detail, with a prediction at the end of the most promising future applications.

Permafrost degradation due to climate warming would potentially increase the release of previously frozen soil carbon and change the carbon budget of the cold region ecosystem. The underlying permafrost degradation would be effectively mediated by soil surface freezing-thawing (FT) processes. Aboveground vegetation can regulate soil FT processes, however its effects on ground thermal transfer have not been well represented by ecosystem models. In this study, we improved the hydrothermal module of the Boreal Ecosystem Productivity Simulator (BEPS) through more careful parameterization of snowpack density, puddled water, soil organic matter and super-cooled soil water. The impacts of vegetation on the soil surface FT processes have also been investigated using the improved BEPS model and the measured soil temperature data at forest and grassland sites on the southern edge of permafrost region in Mongolia and northeastern China. The improved BEPS model performs better than the original model in simulations of soil temperature and soil FT processes. Smaller amplitudes of soil diurnal FT cycles were found in forest sites compared to grassland sites. Forest sites have delayed soil thaw timing and similar soil freezing time compared to grassland sites. Differences in snow depths and soil organic matter content due to distinct vegetation community structures have considerable influences on the disparity in soil FT processes. Thus, it is important to improve the simulation of the impacts of vegetation on soil surface FT processes for better forecasting the permafrost degradation.

Code-switching (CS) detection refers to the automatic detection of language switches in code-mixed utterances. This task can be achieved by using a CS automatic speech recognition (ASR) system that can handle such language switches. In our previous work, we have investigated the code-switching detection performance of the Frisian-Dutch CS ASR system by using the time alignment of the most likely hypothesis and found that this technique suffers from over-switching due to numerous very short spurious language switches. In this paper, we propose a novel method for CS detection aiming to remedy this shortcoming by using the language posteriors which are the sum of the frame-level posteriors of phones belonging to the same language. The CS ASR-generated language posteriors contain more complete language-specific information on frame level compared to the time alignment of the ASR output. Hence, it is expected to yield more accurate and robust CS detection. The CS detection experiments demonstrate that the proposed language posterior-based approach provides higher detection accuracy than the baseline system in terms of equal error rate. Moreover, a detailed CS detection error analysis reveals that using language posteriors reduces the false alarms and results in more robust CS detection., Accepted for publication at Interspeech 2019