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Videos capture events that typically contain multiple sequential, and simultaneous, actions even in the span of only a few seconds. However, most large-scale datasets built to train models for action recognition in video only provide a single label per video. Consequently, models can be incorrectly penalized for classifying actions that exist in the videos but are not explicitly labeled and do not learn the full spectrum of information present in each video in training. Towards this goal, we present the Multi-Moments in Time dataset (M-MiT) which includes over two million action labels for over one million three second videos. This multi-label dataset introduces novel challenges on how to train and analyze models for multi-action detection. Here, we present baseline results for multi-action recognition using loss functions adapted for long tail multi-label learning, provide improved methods for visualizing and interpreting models trained for multi-label action detection and show the strength of transferring models trained on M-MiT to smaller datasets. [ABSTRACT FROM AUTHOR]

Videos capture events that typically contain multiple sequential, and simultaneous, actions even in the span of only a few seconds. However, most large-scale datasets built to train models for action recognition in video only provide a single label per video. Consequently, models can be incorrectly penalized for classifying actions that exist in the videos but are not explicitly labeled and do not learn the full spectrum of information present in each video in training. Towards this goal, we present the Multi-Moments in Time dataset (M-MiT) which includes over two million action labels for over one million three second videos. This multi-label dataset introduces novel challenges on how to train and analyze models for multi-action detection. Here, we present baseline results for multi-action recognition using loss functions adapted for long tail multi-label learning, provide improved methods for visualizing and interpreting models trained for multi-label action detection and show the strength of transferring models trained on M-MiT to smaller datasets. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic continues to impose a huge threat on human health due to rapid viral mutations. Thus, it is imperative to develop more potent antivirals with both prophylactic and treatment functions. In this study, we screened for potential antiviral compounds from Sarcandra glabra (SG) against Cathepsin L and HIV-1 proteases. A FRET assay was applied to investigate the inhibitory effects and UPLC-HRMS was employed to identify and quantify the bioactive components. Furthermore, molecular docking was carried out to get a glimpse of the binding of active compounds to the proteases. Our results showed that the SG extracts (SGW, SG30, SG60, and SG85) inhibited HIV-1 protease with an IC50 of 0.003~0.07 mg/mL and Cathepsin L protease with an IC50 of 0.11~0.26 mg/mL. Fourteen compounds were identified along with eight quantified from the SG extracts. Chlorogenic acid, which presented in high content in the extracts (12.7~15.76 µg/mg), possessed the most potent inhibitory activity against HIV-1 protease (IC50 = 0.026 mg/mL) and Cathepsin L protease (inhibition: 40.8% at 0.01 mg/mL). Thus, SG extracts and the active ingredients could potentially be used to prevent/treat viral infections, including SARS-CoV-2, due to their dual-inhibition functions against viral proteases. [ABSTRACT FROM AUTHOR]

• Wild grapes have strong stress resistance, which is of great significance for broadening the gene pool of grape resources. • There are many wild grape resources in China, which are widely distributed and need real-time and rapid identification methods. • The application of deep learning technology in variety identification has the advantages of non-destructive, efficient and labor-saving. There are more than 70 species of Vitis in the world, and 40 species, 1 subspecies and 13 varieties of Vitis native from China. Wild grapes are diverse and complex, and it is difficult to identify. As an important research direction, deep learning can quickly extract the deep features of images under the premise of ensuring high accuracy, and is widely used in the field of image classification and recognition. In this study, the images of mature leaves of 23 species of wild grapes under natural conditions were selected as the research objects, and the images of leaves were collected by smart phones to construct a wild grape leaf data set with a number of 10,077 images. Four deep learning networks (GoogleNet, ResNet-50, ResNet-101, VGG-16) were used to identify the leaf images of wild grapes. The classification network with the highest average accuracy is ResNet-101, average accuracy and recall rate are 98.64 % and 95.98 %, respectively. Among the 23 categories of the detection model, the prediction accuracy of 12 categories reached 100 %, and the recognition recall rate of 13 categories reached 100 %. It proves the feasibility of deep learning network model to identify leaf species in natural environment, and realizes automatic real-time identification of wild grapes, so as to provide reference for the protection, utilization, classification research of wild grapes and variety identification of other crops. [ABSTRACT FROM AUTHOR]

Here, we describe the identification of PARP1/2 as direct binding proteins of andrographolide (Andro) using protein microarray, surface plasmon resonance (SPR), and enzyme activity assays. We then evaluated the proliferation inhibition, apoptosis, and cell migration effects of Andro on the MDA-MB-436 cell line in vitro. The final biological evaluation confirmed that Andro was a highly effective single agent in the MDA-MB-436 xenograft model and had a low hERG-mediated cardiac toxicity. Therefore, Andro represents the first natural product, non-amide member of a novel nanomolar-potency PARP1/2 inhibitor family. [ABSTRACT FROM AUTHOR]

The destructive power of tropical cyclones is driven by latent heat released from water condensation and is inevitably linked to the abundance of aerosols as cloud condensation nuclei. However, the aerosol effects are unaccounted for in most operational hurricane forecast models. We combined multisource measurements and cloud‐resolving model simulations to show fundamentally altered cloud microphysical and thermodynamic processes by anthropogenic aerosols during Hurricane Harvey. Our observational analyses reveal intense lightning and precipitation in the proximity of Houston industrial areas, and these hot spots exhibit a striking geographic similarity to a climatological maximum of lightning flash density in the south‐central United States. Our ensemble cloud‐resolving simulations of Hurricane Harvey indicate that aerosols increase precipitation and lightning by a factor of 2 in the Houston urban area, unraveling the key anthropogenic factor in regulating flooding during this weather extreme. Plain Language Summary: The catastrophic flooding during Hurricane Harvey has received major attention, but the cause remains mysterious. The destructive power of tropical cyclones is produced by the latent heat release from phase change of water, which is linked to airborne particles emitted from vehicles and petrochemical plants. By combining observation and model simulations, our work provides microphysical and thermodynamic insights into the cause of the catastrophic flooding during Hurricane Harvey by the aerosols from industrial sources. Our discovery underscores the importance of representing the effects of anthropogenic aerosols for accurate short‐term forecast and climate projection of tropical cyclones to minimize future catastrophic destruction along the highly industrialized Gulf of Mexico region. Key Points: Aerosol increases accumulative precipitation by a factor of 2T and invigorates lightning activities in Houston during Hurricane HarveyObservations show intense lightning over Houston which exhibits geographic similarity to climatological maximum lightning flash densityTo better forecast extreme weather events, it is essential to account for aerosol effects in operational weather forecast models [ABSTRACT FROM AUTHOR]

How to choose a chaotic sequence to construct a chaotic S-box is a key factor to determine the performance of the S-box. In this paper, a construction method for chaotic S-box based on fireworks algorithm is proposed, in which the fireworks algorithm is used to search for the optimal solution in the solution space of the Lorenz chaotic system. The performances of S-box are tested through the nonlinearity, differential uniformity, strict avalanche criterion, output bits independence criterion and bijectivity, and compared with the existing classical S-boxes based on the Lorenz chaotic system. The results indicate that the S-box in this paper has more excellent cryptographic characteristics, which will provide a new idea for the efficient generation of chaotic S-box. [ABSTRACT FROM AUTHOR]

In the present work, we reported the design, synthesis, and in vitro cytotoxicity evaluation of novel dihydroartemisinin-isatin hybrids tethered via different length of esters against MCF-7, MDA-MB-231, MCF-7/ADR and MDA-MB-231/ADR breast cancer cell lines. The preliminary results showed that the majority of the hybrids exhibited good anti-breast cancer cell activity. In particular, hybrids 7 g and 7n not only were more potent than ART, DHA and ADR against the four tested breast cancer cell lines, but also were non-toxic towards normal MCF-10A breast cells. The selectivity index values of hybrids 7 g and 7n were > 12.83 and > 25.97 respectively, revealing their excellent safety and selectivity profiles. The drug-resistant index values of hybrids 7 g and 7n were in a range of 0.33 to 1.12, implying that these hybrids had the potential to overcome drug resistance. Accordingly, hybrids 7 g and 7n could be considered as potential lead molecules for the development of novel anti-breast cancer agents with minimal untoward events to normal human cells. The structure-activity relationships indicated that the length of ester likner between DHA and isatin as well as substituents at C-3 and C-5 positions of isatin moiety had great impact on the activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Visible‐light photoredox‐catalyzed metal‐free one‐pot tandem regioselective synthesis of C4‐phosphorylated phthalazin‐1(2H)‐ones from arylhydrazines, 2‐formylbenzoic acids with diarylphosphine oxides is described. This three‐component transformation occurs smoothly under mild conditions, providing regiospecific access to various phosphorylated products in 73–91% yield. The efficacy of the current catalysis arises from the use of organic 1,2,3,5‐tetrakis(carbazol‐9‐yl)‐4,6‐dicyanobenzene (4CzIPN) as the photocatalyst and cheap K2S2O8 as the oxidant. [ABSTRACT FROM AUTHOR]

A series of ester tethered dihydroartemisinin‐3‐(oxime/thiosemicarbazide)isatin hybrids 7a–p were designed, synthesized, and assessed for their antiproliferative activity against MCF‐7, MDA‐MB‐231, MCF‐7/ADR, and MDA‐MB‐231/ADR breast cancer cell lines. Among them, hybrids 7a,f (IC50: 1.33–3.84 µM) showed potent activity against triple‐negative (MDA‐MB‐231 and MDA‐MB‐231/ADR) breast cancer cell lines, and hybrid 7f (IC50: 3.90 and 10.18 µM) also demonstrated promising activity against estrogen receptor‐positive breast cancer cells (MCF‐7 and MCF‐7/ADR), and the activity was superior to these of artemisinin, dihydroartemisinin, and ADR, revealing their potential to fight against both drug‐sensitive and drug‐resistant breast cancers. The enriched structure–activity relationships may facilitate further design of more active candidates. [ABSTRACT FROM AUTHOR]

A continental cloud complex, consisting of shallow cumuli, a deep convective cloud (DCC), and stratus, is simulated by a cloud-resolving Weather Research and Forecasting Model to investigate the aerosol microphysical effect (AME) and aerosol radiative effect (ARE) on the various cloud regimes and their transitions during the Department of Energy Routine Atmospheric Radiation Measurement Aerial Facility Clouds with Low Optical Water Depths Optical Radiative Observations (RACORO) campaign. Under an elevated aerosol loading with AME only, a reduced cloudiness for the shallow cumuli and stratus resulted from more droplet evaporation competing with suppressed precipitation, but an enhanced cloudiness for the DCC is attributed to more condensation. With the inclusion of ARE, the shallow cumuli are suppressed owing to the thermodynamic effects of light-absorbing aerosols. The responses of DCC and stratus to aerosols are monotonic with AME only but nonmonotonic with both AME and ARE. The DCC is invigorated because of favorable convection and moisture conditions at night induced by daytime ARE, via the so-called aerosol-enhanced conditional instability mechanism. The results reveal that the overall aerosol effects on the cloud complex are distinct from the individual cloud types, highlighting that the aerosol-cloud interactions for diverse cloud regimes and their transitions need to be evaluated to assess the regional and global climatic impacts. [ABSTRACT FROM AUTHOR]

• EA can reverse and raise the pain threshold in hyperalgesic priming model rats. • EA regulates the expression of p-p38, IL-33, and ST2 in astrocytes in SDHs. • EA prevents acute to chronic pain development by inhibiting IL-33/ST2 signaling. • This will help clinicians understand the mechanisms of EA analgesia. Chronic pain is a complex health issue. Compared to acute pain, which has a protective value, chronic pain is defined as persistent pain after tissue injury. Few clinical advances have been made to prevent the transition from acute to chronic pain. Electroacupuncture (EA), the most common form of acupuncture, is widely used in clinical practice to relieve pain. The hyperalgesic priming model, established via a carrageenan injection followed by a prostaglandin E 2 injection, was used to investigate the development or establishment of chronic pain. We observed the hyperalgesic effect of EA on rats and investigated the expression p38 mitogen-activated protein kinase, interleukin-33 (IL-33), and its receptor ST2 in astrocytes in the L4–L6 spinal cord dorsal horns (SDHs) after EA. The IL-33/ST2 signaling pathway in SDH is associated with the development of chronic pain. EA can reverse the pain threshold in hyperalgesic priming model rats and regulates the expression of phosphorylated p38, IL-33, and ST2 in astrocytes in the L4–L6 SDHs. We discovered that EA raises the pain threshold. This suggests that EA can prevent the development or establishment of chronic pain by inhibiting IL-33/ST2 signaling in the lower central nervous system. EA can alleviate the development or establishment of chronic pain by modulating IL-33/ST2 signaling in SDHs. Our findings will help clinicians understand the mechanisms of EA analgesia. [ABSTRACT FROM AUTHOR]

Panaxatriol, a triterpene bearing a steroid-like structure similar to cardiac glycosides, was presumed to share the same bioactivity with cardiac glycosides, and may be a potential Na + , K + -ATPase inhibitor. In this paper, a series of panaxatriol derivatives were synthesized and evaluated for Na + , K + -ATPase inhibitory activities. The results of biological tests showed that more than half of the synthesized derivatives presented increased inhibitory activities compared with panaxatriol. Of these compounds, 13a with a 3, 4- seco skeleton showed the most potent inhibitory activity, which was equal to that of the standard drug digoxin. To understand the binding mode of the most active compound, molecular docking study of 13a with Na + , K + -ATPase was conducted. Therefore, 13a may serve as a new lead compound for the development of novel Na + , K + -ATPase inhibitors. [ABSTRACT FROM AUTHOR]

Aerosol-cloud-radiation interactions represent one of the largest uncertainties in the current climate assessment. Much of the complexity arises from the non-monotonic responses of clouds, precipitation and radiative fluxes to aerosol perturbations under various meteorological conditions. In this study, an aerosol-aware WRF model is used to investigate the microphysical and radiative effects of aerosols in three weather systems during the March 2000 Cloud Intensive Observational Period campaign at the US Southern Great Plains. Three simulated cloud ensembles include a low-pressure deep convective cloud system, a collection of less-precipitating stratus and shallow cumulus, and a cold frontal passage. The WRF simulations are evaluated by several ground-based measurements. The microphysical properties of cloud hydrometeors, such as their mass and number concentrations, generally show monotonic trends as a function of cloud condensation nuclei concentrations. Aerosol radiative effects do not influence the trends of cloud microphysics, except for the stratus and shallow cumulus cases where aerosol semi-direct effects are identified. The precipitation changes by aerosols vary with the cloud types and their evolving stages, with a prominent aerosol invigoration effect and associated enhanced precipitation from the convective sources. The simulated aerosol direct effect suppresses precipitation in all three cases but does not overturn the aerosol indirect effect. Cloud fraction exhibits much smaller sensitivity (typically less than 2%) to aerosol perturbations, and the responses vary with aerosol concentrations and cloud regimes. The surface shortwave radiation shows a monotonic decrease by increasing aerosols, while the magnitude of the decrease depends on the cloud type. [ABSTRACT FROM AUTHOR]

Atmospheric aerosols affect weather and global general circulation by modifying cloud and precipitation processes, but the magnitude of cloud adjustment by aerosols remains poorly quantified and represents the largest uncertainty in estimated forcing of climate change. Here we assess the effects of anthropogenic aerosols on the Pacific storm track, using a multiscale global aerosol-climate model (GCM). Simulations of two aerosol scenarios corresponding to the present day and preindustrial conditions reveal long-range transport of anthropogenic aerosols across the north Pacific and large resulting changes in the aerosol optical depth, cloud droplet number concentration, and cloud and ice water paths. Shortwave and longwave cloud radiative forcing at the top of atmosphere are changed by -2.5 and +1.3 W m-2, respectively, by emission changes from preindustrial to present day, and an increased cloud top height indicates invigorated midlatitude cyclones. The overall increased precipitation and poleward heat transport reflect intensification of the Pacific storm track by anthropogenic aerosols. Hence, this work provides, for the first time to the authors' knowledge, a global perspective of the effects of Asian pollution outflows from GCMs. Furthermore, our results suggest that the multiscale modeling framework is essential in producing the aerosol invigoration effect of deep convective clouds on a global scale. [ABSTRACT FROM AUTHOR]

Panaxatriol (PT) is a natural product derived from ginseng that possesses cardioprotective effects in isolated rat hearts. To develop more potent therapeutic agents against myocardial ischemia/reperfusion (MI/R) injury from natural products, a novel series of heterocycle ring-fused panaxatriol derivatives were designed and synthesized. In vitro results showed that approximately half of them exhibited increased cytoprotective activity compared with PT in a cardiomyocyte model of oxygen-glucose deprivation and reperfusion (OGD/R) injury. Furthermore, the in vitro activity of the representative derivative, compound 18 , was also confirmed in a rat model of MI/R injury. In vivo results showed that 18 can markedly reduce myocardial infarction size, decrease circulating cardiac troponin I (cTnI) leakage, and alleviate cardiac tissue damage in the rats. Therefore, these findings provide the basis for further development of novel anti-MI/R injury agents. Image 1 • A series of heterocycle ring-fused panaxatriol (PT) derivatives were designed and synthesized. • The compounds were evaluated for cardioprotective activity in a cardiomyocyte model of OGD/R injury. • Approximately half of the PT derivatives exhibited more potent cytoprotective activity than PT. • Representative compound, 18 , attenuated the reperfusion injury in a rat model of myocardial infarction. [ABSTRACT FROM AUTHOR]