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Annona squamosa (AS) and Cinnamomum tamala (CT) leaves have been used traditionally and have well reported various pharmacological activities which justify their topical use. But the majority of compounds present are phenolic compounds which due to their polar nature are unable to permeate through the skin. Therefore, polyherbal phytosomes of ethanolic extracts of AS and CT were combined in a ratio of 1:1 to get polyherbal Ethanolic extract (PHEE) and polyherbal phytosomes (PHP) were prepared and optimized using Response Surface methodology by applying Central Composite design (CCD) for studying the effect of drug soya lecithin ratio and speed of rotation on responses like vesicle size and entrapment efficiency. Followed by numerical optimization, PHP with vesicle size of 215.5 ± 0.45 nm and Entrapment efficiency of 85.24 ± 0.05% were obtained. These PHP were characterized with FTIR, DSC, SEM and XRD. The PHP showed % cumulative drug release of 84.22 ± 5.62%. For easy application on the skin these phytosomes were incorporated in Carbopol 934 gel matrix and evaluated for physical appearance, pH, viscosity and drug content. The ex vivo permeation of the phytosomal gel (PG) was compared with a conventional gel containing PHEE. A significant improvement in permeation was observed in case of PG with 36.62 ± 3.33 µg/cm2 of drug permeated in 24 hours whereas 17.06 ± 1.54 µg/cm2 through the conventional gel. The PHP and PG were found stable during stability studies for six months. Polyherbal phytosomal gel can be a good carrier for herbal extracts for topical delivery. [ABSTRACT FROM AUTHOR]

Inland and coastal environments are complex ecosystems composed of suspended and dissolved materials, affecting light propagation within the water column. Satellite-based water quality research relies on water optical properties provided by optical sensors on board of polar orbit satellites since the 1980's. Specifically, Geostationary (GEO) ocean colour satellites offer high temporal resolution (e.g. every 15-minute observations), moderate spatial resolution (0.5–1 km) at regional scale, making them a promising alternative to polar orbiting satellites for near-continuous monitoring of highly dynamic aquatic ecosystems. This literature review examines the evolution of geostationary satellite technology and its applications in monitoring inland and coastal waters. A summary of the most relevant studies using geostationary sensors is provided for key water quality indicators such as chlorophyll-a and algal organisms, total suspended solids, and turbidity. Also, geostationary missions were well-detailed, with their available sensors and characteristics. Although this research topic is still incipient, recent studies have demonstrated the potential of GEO multi-spectral observations in understanding sub-daily water quality patterns. Notably, most research studies have focused on Asia, suggesting unexplored opportunities globally. Advanced Himawari Imager (AHI) and Geostationary Ocean Colour Imager (GOCI) have been used to improve water quality estimates, and inherent challenges were documented, such as algorithm validation, limited spatial resolution, and high volume of images and auxiliary files to be managed. The opportunities for new studies range from algorithm development for atmospheric correction, cloud masking, and bidirectional reflectance corrections to inter-comparison with existing sun-synchronous satellites. Geostationary satellites are promising avenues for future research on near-continuous monitoring of inland and coastal water resources. [ABSTRACT FROM AUTHOR]

With the increased availability of multi-view satellite images, the number of investigations on 3D urban scene reconstruction from multiple satellite images is also increasing. Conventional Multi-View Stereo (MVS) pipelines require the calibrated pose information of the satellite cameras to determine the epipolar geometry and the 3D structure of the stereo correspondences. In this study, we propose a novel Monocular Height estimation and Fusion (MHF) method for 3D reconstruction from uncalibrated multi-view satellite images. By employing a learned monocular depth network, the proposed method first obtains the height map of each satellite image. Second, all height maps obtained from the multi-view images are fused to a refined height map in each image plane. To fuse the height maps, all maps are affine transformed to a virtual reference coordinate system and the transformed maps are then projected to the image plane of each camera coordinate system. The monocular depth network was trained and evaluated on the Data Fusion Contest 2019 (DFC19) dataset including Jacksonville, FL, and Omaha, NE. We also evaluate the ATL-SN4 dataset covering Atlanta, GA to test on untrained new urban scenes. [ABSTRACT FROM AUTHOR]

Synthetic Aperture Radar (SAR) plays an important role in marine ship management due to its all-weather, multi-band, and multi-polar characteristics, but the complex environment on the ground and the limitation of the imaging principle lead to the existence of large noise interference in SAR imaging, which poses a greater challenge to the existing ship detection algorithm. To address the problem of low detection rate and high false alarm rate of ship detection in noise-laden SAR images, we propose a detection algorithm based on convolutional neural network and transformer. First, we design the processing structure of multi-scale feature maps based on the advantages of transformer global processing capability, then we use weighted fusion of different scale feature maps after global processing to enhance the detection capability of the model for noise-containing targets, and finally, the model is evaluated using the high noise SAR datasets (HNSAR) we constructed. The experimental results show that our model has better detection of noise-containing SAR images compared with other deep learning models. [ABSTRACT FROM AUTHOR]

We present a generalisation of the Maier-Saupe (MS) theory that incorporates the description of the ferroelectric nematic phase (NF) within its scope of application. The extension of the theory is carried out in a natural way, by adding to the nematic potential of MS a term proportional to cosθ and to the polar order parameter , where θ is the angle between the long molecular axis and the spontaneous polarisation. The NF phase can be reached by cooling from the isotropic phase with or without the formation of an intermediate normal nematic phase, depending on the relative intensity of the polar and non-polar terms of the nematic potential. For both phase sequences all the transitions are first order. The temperature dependence of the polar and non-polar order parameters is calculated, and some results derived from the theory are compared with the experimental observations. It is argued that the theory is a valuable first approximation to describe some of the properties of ferroelectric nematics. [ABSTRACT FROM AUTHOR]

The rapid decline of Arctic sea ice has been reminding us the significant impacts caused by global warming. However, the other side of the coin is that this opens a window to utilize the Arctic sea routes in the summer seasons, bringing remarkable economic benefits for ocean transportation between Asia and Europe. However, commercial vessels with low ice classes must tackle substantial environmental challenges in the Arctic sea routes, particularly those caused by variable sea ice, even in the melting seasons. Therefore, the science-based support for shipping safety in the Arctic sea routes is being given more prominence. Emerging satellite remote sensing technology plays a critical role in environmental monitoring in the Arctic. This paper reviews state-of-the-art satellite observations on monitoring sea ice and potential applications on supporting shipping activities in the Arctic Ocean. Moreover, we introduced a recently developed system based on satellite observations to support the safe transportation of Chinese cargo vessels in the Arctic northern sea route, demonstrating the efforts by both the science and business communities to promote the development of the polar silk road. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) estimates based on remote sensing are constrained by the spatial and temporal resolution of spaceborne observations. Therefore, the choice to be made is whether modelling at high temporal resolution with geostationary satellites at the cost of the spatial detail, or spatially detailed instantaneous modelling at overpass-time with polar-orbit satellites. This study aimed at exploiting the strength of both modelling approaches and derive daily ET estimates with cell size 1.0 km. The study was conducted in four sites with different land cover arrangements and catalogued as wetlands. The methodological approach was based on the algorithm behind the operational ET product of the Satellite Application Facility on Land Surface Analysis (LSA-SAF) initiative. The examined period comprised the end of the Spot-Végétation (Spot-V) mission and the first year of Proba-V operational modus. Two aspects were investigated: 1. The adequacy of combining observations from geostationary and Spot-V and Proba-V satellite missions for obtaining the target product; and, 2. The intercompatibility of ET estimates based on Spot-V and Proba-V so that continuous series over the operational period of both missions could be built. The comparison of simulated ET with in situ measured fluxes (eddy covariance) showed that the introduction of more spatial detail through polar-satellite observations resulted in the reduction of bias and root-mean-square error in ET estimates, as compared with estimations where Earth observation data were taken from geostationary satellites only. Moreover, the signals derived from Spot-V and Proba-V exhibited similarity during the period of operational overlap; especially in non-cultivated surfaces. This suggests that continuity objective of these two missions can be exploited in the estimation of ET time series. [ABSTRACT FROM AUTHOR]

Stresses acting on fault systems before major earthquakes can produce thermal anomalies; these abnormalities can be observed using multi-sensor satellite data. Moderate resolution spectro-radiometer on board the terra and aqua satellites can provide thermal infrared (TIR) imaging data for land and ocean. These TIR data have recorded short-lived thermal anomaly prior to major earthquakes. It is suggested by others that these electromagnetic (EM) phenomena relate to stress build up before earthquakes. The objective of this study is to find an association between spatial extent and temporal evolution of thermal anomalies and known major earthquakes near the boundary of Nazca plate and South American plate. Our approach is to map the TIR transient fields from polar orbiting satellites and analysing those data using time series temperature plots to detect the abnormal thermal trends before the earthquake. This study concentrated on marine earthquakes to detect the changes in both land and ocean before seismic activity. [ABSTRACT FROM AUTHOR]