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Combinations of multi-sensor remote sensing images and machine learning have attracted much attention in recent years due to the spectral similarity of wetland plant canopy. However, the integration of hyperspectral and quad-polarization synthetic aperture radar (SAR) images for classifying marsh vegetation has still been faced with the challenges of using machine learning algorithms. To resolve this issue, this study proposed an approach to classifying marsh vegetation in the Honghe National Nature Reserve, northeast China, by combining backscattering coefficient and polarimetric decomposition parameters of C-band and L-band quad-polarization SAR data with hyperspectral images. We further developed an ensemble learning model by stacking Random Forest (RF), CatBoost and XGBoost algorithms for marsh vegetation mapping and evaluated its classification performance of marsh vegetation between combinations of hyperspectral and full-polarization SAR data and any of the lone sensor images. Finally, this paper explored the effect of different polarimetric decomposition methods and wavelengths of radar on classifying wetland vegetation. We found that a combination of ZH-1 hyperspectral images, C-band GF-3, and L-band ALOS-2 quad-polarization SAR images achieved the highest overall classification accuracy (93.13%), which was 5.58–9.01% higher than that only using C-band or L-band quad-polarization SAR images. This study confirmed that stacking ensemble learning provided better performance than a single machine learning model using multi-source images in most of the classification schemes, with the overall accuracy ranging from 77.02% to 92.27%. The CatBoost algorithm was capable of identifying forests and deep-water marsh vegetation. We further found that L-band ALOS-2 SAR images achieved higher classification accuracy when compared to C-band GF-3 polarimetric SAR data. ALOS-2 was more sensitive to deep-water marsh vegetation classification, while GF-3 was more sensitive to shallow-water marsh vegetation mapping. Finally, scattering model-based decomposition provided important polarimetric parameters from ALOS-2 SAR images for marsh vegetation classification, while eigenvector/eigenvalue-based and two-component decompositions produced a great contribution when using GF-3 SAR images. [ABSTRACT FROM AUTHOR]

Staphylococcus haemolyticus (S. haemolyticus) is the second most commonly isolated coagulase-negative staphylococcus (CoNS) in patients with hospital-acquired infections. It can produce phenol-soluble modulin (PSM) toxins and form biofilms. Compared with the wealth of information on Staphylococcus aureus and Staphylococcus epidermidis , very little is known about S. haemolyticus. There is an urgent need to find an effective preparation to combat the harm caused by S. haemolyticus infection. Chinese herbs have been utilized to cure inflammation and infectious diseases and have a long history of anticancer function in China. Here, we modified fusaric acid characterized from the metabolites of Gibberella intermedia , an endophyte previously isolated from Polygonum capitatum. This study shows that fusaric acid analogs (qy17 and qy20) have strong antibacterial activity against S. haemolyticus. In addition, crystal violet analyses and scanning electron microscopy observations demonstrated that qy17 inhibited biofilm formation and disrupted mature biofilms of S. haemolyticus in a dose-dependent manner. Additionally, it reduced the number of live bacteria inside the biofilm. Furthermore, the antibiofilm function of qy17 was achieved by downregulating transcription factors (sigB), transpeptidase genes (srtA), and bacterial surface proteins (ebp , fbp) and upregulating biofilm-related genes and the density-sensing system (agrB). To further elucidate the bacteriostatic mechanism, transcriptomic analysis was carried out. The following antibacterial mechanisms were uncovered: (i) the inhibition of heat shock (clpB , groES , groL , grpE , dnaK , dnaJ)-, oxidative stress (aphC)- and biotin response (bioB)-related gene expression, which resulted in S. haemolyticus being unable to compensate for various stress conditions, thereby affecting bacterial growth; and (ii) a reduction in the expression of PSM-beta (PSMβ1, PSMβ2, PSMβ3) toxin- and Clp protease (clpP , clpX)-related genes. These findings could have major implications for the treatment of diseases caused by S. haemolyticus infections. Our research reveals for the first time that fusaric acid derivatives inhibit the expression of biofilm formation-related effector and virulence genes of S. haemolyticus. These findings provide new potential drug candidates for hospital-acquired infections caused by S. haemolyticus. [ABSTRACT FROM AUTHOR]

The middle-frequency sensorineural hearing loss (MFSNHL) is rare among hereditary non-syndromic hearing loss. To date, only three genes are reported to be associated with MFSNHL, including TECTA, EYA4 and COL11A2. In this report, we analyzed and explored the clinical audiological characteristics and the causative gene of a Chinese family named HG-Z087 with non-syndromic autosomal dominant inherited MFSNHL. Clinical audiological characteristics and inheritance pattern of a family were evaluated, and pedigree was drawn based on medical history investigation. Our results showed that the Chinese family was characterized by late onset, progressive, non-sydromic autosomal dominant MFSNHL. Targeted exome sequencing, conducted using DNA samples of an affected member in this family, revealed a novel heterozygous missense mutation c.1643C>G in exon 18 of EYA4, causing amino-acid (aa) substitution Arg for Thr at a conserved position aa-548. The p.T548R mutation related to hearing loss in the selected Chinese family was validated by Sanger sequencing. However, the mutation was absent in control group containing 100 DNA samples from normal Chinese families. In conclusion, we identified the pathogenic gene and found that the novel missense mutation c.1643C>G (p.T548R) in EYA4 might have caused autosomal dominant non-syndromic hearing impairment in the selected Chinese family. [ABSTRACT FROM AUTHOR]

Vegetation phenology is a sensitive indicator which can comprehensively reflect the response of wetland vegetation to external environment changes. However, the time-series monitoring wetland vegetation phenological changes and clarifying its response to hydrology and meteorology still face great challenges. To fill these research gaps, this paper proposed a novel time-series approach for monitoring phenological change of marsh vegetation in Honghe National Nature Reserve (HNNR), Northeast China, using continuous change detection and classification (CCDC) algorithm and Landsat and Sentinel-1 SAR images from 1985 to 2021. We evaluated the spatio-temporal response relationship of phenological characteristics to hydro-meteorological factors by combining CCDC algorithm with partial least squares regression (PLSR). Finally, this study further explored the intra-annual loss and restoration of marsh vegetation in response to hydro-meteorological factors using the transfer entropy (TE) and CCDC-MLSR model constructed by CCDC and Multiple Linear Stepwise Regression (MLSR) algorithms. We found that the bimodal trajectory of phenology reflects two growth processes of marsh vegetation in one year, and high-frequency and high-amplitude loss occurred in shallow-water and deep-water marsh vegetation from April to October, resulting in the loss area within the year was significantly greater than the recovery area. We confirmed that the CCDC algorithm could track the evolution trajectory of time-series phenology of marsh vegetation. We further revealed that precipitation, temperature and frequency of water-level changes are the main driving factors for the spatio-temporal phenological evolution of different marsh vegetation. This study verified the effect of alternative changes of hydrology and climate on loss and recovery of marsh vegetation in each growth stage. The results of this study provide a scientific basis for wetland protection, ecological restoration, and sustainable development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Two new species of the new genus Pseudorogneda of Polycystididae were discovered in a brackish environment from Southern China. Pseudorogneda sinensis n. gen. n. sp., is distinguished by a semicircular double-walled prostate stylet type II that tapers in diameter from proximal to distal with a proximal-to-distal fold, and an inner wall with a funnel-shaped base originating at the midpoint of the outer wall; its flattened tubular prostate stylet type IV exhibits a horn-like base and a proximal-to-distal folded structure on its wall. For Pseudorogneda shenda n. gen. n. sp., its crescent-shaped prostate stylet type II is double-walled and the inner wall has a funnel-shaped base that starts at the proximal 2/3 position of the outer stylet and is fused with the outer stylet to form a sharp distal end; its tubular and slightly-curved prostate stylet type IV exhibits a slit and a distal fold. Phylogenetic analysis of 18S rDNA and 28S rDNA sequences shows that the two novel species are clustered to form an independent clade from other genera, which is consistent with morphological comparison in the establishment of two new species in a new genus.

Two new species of Rhabdocoela, namely Alcha sinensis n. sp. (Polycystididae) and Trigonostomum sinensis n. sp. (Trigonostomidae), were discovered from the intertidal zone of eastern Shenzhen City, China. For A. sinensis n. sp., the stylet consists of two symmetrical triangular plates and one lamellar plate. All three plates are jagged at their posterior ends. The anterior end of the stylet connects to a thick muscular layer, which causes its movement. For T. sinensis n. sp., the copulatory organ consists of a long-tubular stylet and two "T"-shaped plates (plate I and plate II). The stylet bends 120° at 25% of its length from the base and extends straight distally. Two "T" plates are connected to each other and surround the stylet. Plate I is hook-shaped at its distal end, and plate II has a similar length but only half the width of plate I. The phylogenetic (18S rDNA and 28S rDNA) results also support the establishment of these two new species. On the basis of the molecular phylogeny and morphology of the copulatory organ and bursa appendage, we propose a new categorization of the species of Trigonostomum.

Two new species of the genus Pogaina Marcus, 1954 (Provorticidae), namely Pogaina sinensis n. sp. and Pogaina shenzhenensis n. sp. are described from brackish water in the intertidal zone of Shenzhen Bay. For P. sinensis n. sp., the tubular stylet is slightly curved at the distal end and a fusiform structure with a flange is present at 66% of the stylet. The flange encircles the stylet, with its ends attached to the midpoint and the distal end of the stylet. For P. shenzhenensis n. sp., the stylet has a N-shaped overall morphology. A band provided with dense needle-like structures is present at the distal end of the stylet. Both the morphological (stylet) and phylogenetic (18S rDNA and 28S rDNA) analyses support the establishment of these two new species.