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Marine oil spills are among the most significant sources of marine pollution. Synthetic aperture radar (SAR) has been used to improve oil spill observations because of its advantages in oil spill detection and identification. However, speckle noise, weak boundaries, and intensity inhomogeneity often exist in the oil spill regions of SAR imagery, which will seriously affect the accurate identification of oil spills. To enhance marine oil spill segmentation of SAR images, a fast, edge-preserving framework based on the distance-regularized level set evolution (DRLSE) model was proposed. Specifically, a bilateral filter penalty term is designed and incorporated into the DRLSE energy function (BF-DRLSE) to preserve the edges of oil spills, and an adaptive initial box boundary was selected for the DRLSE model to reduce the operation time complexity. Two sets of RadarSat-2 SAR data were used to test the proposed method. The experimental results indicate that the bilateral filtering scheme incorporated into the energy function during level set evolution improved the stability of level set evolution. Compared with other methods, the proposed improved BF-DRLSE algorithm displayed a higher overall segmentation accuracy (97.83%). In addition, using an appropriate initial box boundary for the DRLSE method accelerated the global search process, improved the accuracy of oil spill segmentation, and reduced computational time. Therefore, the results suggest that the proposed framework is effective and applicable for marine oil spill segmentation. [ABSTRACT FROM AUTHOR]

Based on a study of 49 conodont and 57 geochemical samples from the Upper Triassic, carbonate-dominated Dengdengqiao Formation, Qinling Basin, China, the Carnian conodonts and carbon isotope records are first reported. Two genera and four species have been identified amongst 87 conodont elements: Mosherella praebudaensis, Mo. longnanensis sp. nov., Mo. sp., and "Misikella" longidentata. The presence of Mo. praebudaensis indicates that the lower part (bed 2) of the formation is attributable to the Julian (lower Carnian) substage. A radiolarian fauna identified in a previous study belongs to the upper Carnian, but the sampling horizon is unclear. The δ13Ccarb curve shows a ∼1.8‰ negative excursion beginning from upper part of bed 3, but its stratigraphic location is uncertain. The Dengdengqiao Formation is clearly at least partly of Carnian age but could include younger strata. The abundant calcareous algae at the section is probably due to some transport rather than preserved in site. The unusual ecosystem with rare marine organisms may reflect long-term stressful and unfavorable conditions at Dengdengqiao. [ABSTRACT FROM AUTHOR]

The stainless steel/Ti/low-carbon steel trimetallic composite plate was successfully fabricated by the explosive welding technique using honeycomb aluminum structure low detonation velocity emulsion explosive. The interfacial microstructure characterizations, elemental distribution, phase transformation and hardness were characterized using optical microscopy (OM), scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and micro-hardness tester. The results indicated that the trimetallic sheet of stainless steel/Ti/low-carbon steel was successfully welded without visible defects and have an excellent bonding quality. The Ti/;ow-carbon steel joining interface had a typical wavy structure and formed about 3 µm thick transition layer. The stainless steel/Ti joining interface had an almost flat structure; meanwhile, the phase transformation of Fe and Ti and the texture occurred at the joining interfaces. The hardness increased near the welding interface and sharply increased in the melted zones. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) and polychlorinated naphthalenes (PCNs) are of growing concern due to their toxic effects on the environment and human health. There is an urgent need for strategies to monitor and analyze the coexistence of PFASs and PCNs, especially in food samples at trace levels, to ensure food safety. Herein, a novel β-cyclodextrin (β-CD) derived fluoro-functionalized covalent triazine-based frameworks named CD-F-CTF was firstly synthesized. This innovative framework effectively combines the porous nature of the covalent organic framework and the host-guest recognition property of β-CD enabling the simultaneous extraction of PFASs and PCNs. Under the optimal conditions, a simple and rapid method was developed to analyze PFASs and PCNs by solid-phase extraction (SPE) based simultaneous extraction and stepwise elution (SESE) strategy for the first time. When coupled with liquid chromatography−tandem mass spectrometry (HPLC−MS/MS) and gas chromatography−tandem mass spectrometry (GC−MS/MS), this method achieved impressive detection limits for PFASs (0.020 −0.023 ng/g) and PCNs (0.016 −0.075 ng/g). Furthermore, the excellent performance was validated in food samples with recoveries of 76.7–107 % (for PFASs) and 78.0–108 % (for PCNs). This work not only provides a simple and rapid technique for simultaneous monitoring of PFASs and PCNs in food and environmental samples, but also introduces a new idea for the designing novel adsorbents with multiple recognition sites. [Display omitted] • Novel bifunctional covalent triazine-based frameworks with host-guest recognition and fluorous affinity were prepared. • The material exhibited high selective adsorption for PFASs and PCNs. • A SESE-HPLC-MS/MS and SESE-GC-MS/MS method was developed. • The method was sensitive and practical for the determination of PFASs and PCNs in different types of foods. [ABSTRACT FROM AUTHOR]

Despite the widespread use of anaerobic soil disinfestation (ASD) to improve soil health, its impact on soil antibiotics, human pathogenic bacteria (HPB) and antibiotic resistance genes (ARGs) remains unclear. To address this knowledge gap, we conducted an incubation study in manure-amended soil with three treatments: no treatment (CK), crop straw only (CS), and CS combined with water flooding and plastic covering (ASD). The results showed that ASD increased the concentrations of tetracycline by 27 % and β-lactam by 22 %, while depleting macrolide by 51 %. Furthermore, ASD increased the numbers of potential HPB species and genes by 4.1 % and 23 %, respectively. Co-occurrence network analysis demonstrated intensified cooperation and competition among HPB and HNPB (human non-pathogenic bacteria) species under ASD, favoring the prevalence of HPB species such as Escherichia coli , Streptococcus equi , Clostridium tetani , and Bacillus anthracis. Potential HPB species in Proteobacteria exhibited negative correlations with macrolide and β-lactam antibiotics, whereas those in Firmicutes showed positive correlations with tetracycline antibiotics, suggesting that specific bacterial taxa contributed to the production and degradation of antibiotics in response to ASD. Interestingly, CS mitigated the presence of ARGs in soil, while ASD further amplified this reduction, almost eliminating nalC , acrB , OXA-60 , VIM-7 , tetL , and tetQ. The variation in ARG profiles (91.7 %) could be explained by antibiotics, HPB, and HNPB species, indicating their collective contribution to reducing soil ARGs under ASD. Moreover, host prediction and network analysis revealed that, compared with CK, where potential HPB species were the main carriers of ARGs, soil ARGs were less frequently carried by potential HPB species after ASD, indicating a reduction in the collaborative dissemination of HPB and ARGs in manured soil. In conclusion, ASD provides a promising strategy for mitigation of soil biologic contamination, which can have profound significance for environmental safety and agricultural sustainability. • ASD altered soil distribution of tetracycline, β-lactam and macrolide antibiotics. • ASD enriched soil potential HPB species by enhancing connections between HPB and HNPB species. • ASD removed most of the common ARGs, which was weakly correlated with soil antibiotics. • Most potential HPB species boosted by ASD were not the hosts of ARGs in soil. • ASD decreased the risks of synchronous dissemination of HPB and ARGs in soil. [ABSTRACT FROM AUTHOR]

Currently, the dynamic behavior of high-speed long-runout landslides triggered by earthquakes remains unclear due to the complexity of such phenomena. Degradation in the shear strength of rock masses is considered a primary factor contributing to the high velocities and long runout distances of these landslides. In this study, the strength degradation induced by changes in rock joint morphology is analyzed considering a numerical model of the Donghekou landslide, by using discontinuous deformation analysis (DDA). First, an exponential joint roughness degradation function (i.e., JRCm) that depends on displacement is incorporated with the nonlinear Barton–Bandis (B–B) shear strength criterion, and this modified B–B criterion is combined with the DDA. Moreover, a virtual joint is introduced in the DDA to model the propagation of cracks in intact rock masses, in order to simulate the dynamic phenomenon of earthquake-induced landslides. Subsequently, this improved DDA (IDDA) is validated via simulations of a shear test and a sliding block over an inclined plane. Finally, the IDDA is employed to simulate the Donghekou landslide, which was induced by the 2008 Wenchuan earthquake in China. Furthermore, the entire dynamic process of the landslide, including crack propagation, instability, initiation, and motion, is depicted. The simulated deposit patterns obtained via the IDDA are in good agreement with the results of field investigations. The simulation results also prove that the IDDA can reflect key movement behaviors of Donghekou landslide and that the degradation of rock joints significantly influences the long runout distance and high velocity of sliding mass. [ABSTRACT FROM AUTHOR]

Increasing soil organic carbon (SOC) is a widely accepted strategy to offset greenhouse gases and improve soil quality. Straw return can modify SOC dynamics and increase its stock, which are also influenced by soil clay content and metals (i.e. Zn) availability. We conducted a short-term (42 d) incubation study to evaluate SOC dynamics in a calcareous loamy clay soil where available Zn (DTPA extractable) was modified by adding high-Zn straw (HZ-St), low-Zn straw alone (LZ-St) or combined with Zn fertilizer (LZ-St+ZF). Results showed that the DTPA-Zn concentration in soil with LZ-St was similar to the control receiving no straw return or Zn, but it increased by 24.3% in the soil receiving HZ-St and 1.46-fold in the soil receiving LZ-St+ZF. The increased Zn availability enhanced microbial biomass C and N, but did not increase SOC mineralization due to the higher microbial entropy and lower respiration entropy. Greater Zn availability enhanced SOC sequestration probably by promoting the organo-Zn-mineral interactions and thus chemical stabilization. Therefore, adding HZ-St or LZ-St+ZF increases both Zn availability and SOC sequestration in calcareous loamy clay soil. However, long-term and field-based research is necessary to confirm the practical effects of this approach. Abbreviations: DTPA-Zn: diethylenetriaminepentaacetic acid extractable Zn; SOC: soil organic carbon; MBC: microbial biomass carbon; MBN: microbial biomass nitrogen; ZnMB: storage of Zn in microbes; qMB: microbial entropy; qCO2,: respiration entropy; PCA: Principal component analysis, CCA: canonical correspondence analysis. [ABSTRACT FROM AUTHOR]

Limestones of the Xihaoping Member of the Dengying Formation in the Xiaoyangba section, South China, yield the oldest known Cambrian brachiopod–trilobite association. In this member, the trilobite Parabadiella cf. huoi co-occurs with the new brachiopod species Eoobolus incipiens sp. nov. The association provides potential for correlation of lower Cambrian successions and gives novel insights into the origin, palaeobiogeographic distribution and early evolution of linguliform brachiopods. Parabadiella occurs in shallow marine clastic and carbonate rocks in South China, demonstrating a broad distribution for this taxon. The new discovery indicates an early Chiungchussuan age (Parabadiella trilobite Zone, Cambrian Age 3) for the longstanding problematic Xihaoping Member. Furthermore, this earliest Parabadiella – Eoobolus association helps to establish close links with the oldest known trilobite–brachiopod assemblage from the upper Micrina etheridgei Zone (Parabadiella huoi trilobite Zone) in Australia. Eoobolus incipiens represents one of the earliest known linguliform brachiopods, with a distinctive mixture of characters shared with both problematic tommotiids, as well as paterinide, lingulide and acrotretide brachiopods, indicating that these features may be plesiomorphic for the Linguliformea. An age-constrained dispersal mode for early lingulate brachiopods is proposed, indicating that the Subphylum Linguliformea may have originated in East Gondwana and South China during Cambrian Age 3, and only subsequently dispersed to other major Cambrian palaeocontinents (e.g. Siberia, Laurentia, Antarctica, Baltica, Avalonia, West Gondwana, North China) during the late stage of the Cambrian evolutionary radiation of animals. Unlabelled Image • Description of the oldest Cambrian trilobite–brachiopod association from South China • Demonstrates correlation with Cambrian Age 3 faunas from East Gondwana • Eoobolus incipiens sp. nov. is one of the oldest known linguliform brachiopods • South China and East Gondwana were centres of the earliest diversification of the Linguliformea [ABSTRACT FROM AUTHOR]

A porous aromatic framework (PAF) is shown to be a viable sorbent for the adsorption of phenols. To overcome the difficulty of quick adsorption and enrichment by phenols from the matrix, a sorbent material consisting of porous aromatic framework magnetic nanoparticles (PAF MNPs) with a core–shell structure was fabricated by an in situ growth method. The PAF MNP sorbent was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy and other techniques. The factors affecting enrichment performance including the amount of PAF-6 MNPs, sample pH, extraction time and elution conditions were optimized. Under the optimal conditions, a method utilizing high-performance liquid chromatography with an ultraviolet detector (HPLC-UV) was developed to quantify phenols in urine. The method showed good linearity (r ≥ 0.998), good precision (RSD ≤ 9.9%, n = 6) and a low limit of detection (1.0–2.0 ng/mL, S/N = 3), with recoveries performed in urine matrix ranging from 76.7% to 113.2%. The method is simple, time-saving and sensitive. Moreover, compared with traditional mass spectrometry detection methods, this method has advantages in terms of low cost and repeatability. [ABSTRACT FROM AUTHOR]

Parasite–host systems are pervasive in nature but are extremely difficult to convincingly identify in the fossil record. Here we report quantitative evidence of parasitism in the form of a unique, enduring life association between tube-dwelling organisms encrusted to densely clustered shells of a monospecific organophosphatic brachiopod assemblage from the lower Cambrian (Stage 4) of South China. Brachiopods with encrusting tubes have decreased biomass (indicating reduced fitness) compared to individuals without tubes. The encrusting tubes orient tightly in vectors matching the laminar feeding currents of the host, suggesting kleptoparasitism. With no convincing parasite–host interactions known from the Ediacaran, this widespread sessile association reveals intimate parasite–host animal systems arose in early Cambrian benthic communities and their emergence may have played a key role in driving the evolutionary and ecological innovations associated with the Cambrian radiation. Parasitic interactions are difficult to document in the fossil record. Here, Zhang et al. analyze a large population of a Cambrian brachiopod and show it was frequently encrusted by tubes aligned to its feeding currents and that encrustation was associated with reduced biomass, suggesting a fitness cost. [ABSTRACT FROM AUTHOR]

We propose DPCNN (Depth and Pose Convolutional Network), a novel framework for monocular depth with absolute scale and camera motion estimation from videos. DPCNN uses our proposed stereo training examples, in which the spatial and temporal images can be combined more closely, thus providing more priori constraint relationships. In addition, there are two significant features existing in DPCNN: One is that the entire space–temporal-centroid model is established to independently constrain the rotation matrix and the translation vector, so that the spatial and temporal images are collectively limited in a common, real-world scale. The other is to use the triangulation principle to establish a two-channel depth consistency loss, which penalizes inconsistency of the depths estimated from the spatial images and inconsecutive temporal images, respectively. Experiments on the KITTI datasets show that DPCNN achieves the most advanced results in both tasks and outperforms the current monocular methods. [ABSTRACT FROM AUTHOR]