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Dredging is a common technique for managing eutrophication problems in waters, reducing the accumulation of pollutants by removing sediments from the bottom of water bodies. However, dredging can have complex impacts on lake ecosystems, and it is crucial to understand its benefits and mechanisms for the environment. In this paper, the dredged and undredged areas in the Caohai portion of Dianchi Lake were studied to analyze the effects of dredging on nitrogen–phosphorus transport and conversion and changes in nitrogen–phosphorus morphology content and its mechanisms by comparing the nitrogen–phosphorus morphology content and percentage, the nitrogen–phosphorus ratio, and the release contribution of the two areas. It was found that the ratio of stabilized nitrogen (SN) to stabilized phosphorus (SP) in the dredged area was lower than that in the undredged area and the BD-P and TOC content had a large turnaround at the 16–20 cm position of the sediment in the dredged area. The main conclusions were that the dredging would disrupt the internal equilibrium of the lake system for many years, with the greatest effect on the balance of the BD-P in the phosphorus forms of the sediment, and that the column cores of the dredged area at 0 to 16 cm might be newly accumulated sediments after the dredging project. However, with time, the distribution of nitrogen and phosphorus forms in the newly accumulated sediments will gradually reach a new equilibrium. In addition, dredging will also cause significant changes in the retention efficiency of nitrogen and phosphorus in the sediment, and the stable nitrogen and phosphorus forms will be released and transformed into unstable nitrogen and phosphorus forms. [ABSTRACT FROM AUTHOR]

Based on China's newly established Securities Investor Services Center (CSISC), a minority shareholder protection mechanism, we investigated how the CSISC shareholder influences the ESG performance of listed companies. Using a difference-in-differences analysis for a sample of Chinese listed companies during 2013–2017, we found that the pilot reform of CSISC shareholding has a positive influence on the ESG performance of listed companies. We also found that this effect exists in large companies and in companies in non-high-polluting industries. Besides, analysts' attention, external auditing quality, institutional shareholding, and highly-developed market intermediary and legal systems can strengthen the effect of CSISC shareholding on corporate ESG performance. Our findings inspire regulators in emerging markets to establish suitable mechanisms to protect minority shareholder rights in the long run. [ABSTRACT FROM AUTHOR]

In this work, the mechanical behavior and energy absorption characteristics of flexible fabric under hypervelocity impact (HVI) were investigated. Basalt fabric, ultra-high molecular weight polyethylene (UHMWPE) fabric, and aluminum alloy (Al) plate were chosen to be the sample materials for their excellent mechanical properties and applicative prospect in spacecraft shielding. HVI experiments had been conducted with the help of a two-stage light-gas gun facility, wherein Al projectile with 3.97 mm diameter was launched at velocities in the range 4.1~4.3 km/s. Impact conditions and areal density were kept constant for all targets. The microstructural damage morphology of fiber post-impact was characterized using a scanning electron microscope (SEM). Analysis results show that a brittle fracture occurred for Basalt fiber during HVI. On the contrary, the ductile fractures with large-scale plastic deformation and apparent thermal softening/melting of the material had happened on the UHMWPE fiber when subjected to a projectile impact. According to the HVI shielding performance and microstructural damage analysis results, it can be inferred that ductile fractures and thermal softening/melting of the material were the prevailing energy absorption behaviors of UHMWPE fabric, which leads to absorbing more impact energy than Basalt fabric and eventually, contributes the superior shielding performance. [ABSTRACT FROM AUTHOR]

Landslide-generated impulse waves of a mountain-river reservoir will endanger the dam body's stability and the dam structure's safety and even pose a significant threat to the property safety of downstream residents. Timely prediction of dam surface pressure is essential for dam safety assessment. The pressure distribution characteristics and variation law of the gravity dam surface under the impact of landslide-generated impulse waves are studied through a three-dimensional physical model test. The results show that the landslide volume and angle are the key control factors of the first wave amplitude in front of the dam. The maximum and minimum pressures are near the water surface and at two-thirds of the water depth, respectively. The maximum pressure has a power function relationship with the maximum amplitude of the wave in front of the dam. Furthermore, the maximum amplitude of the first wave in front of the dam significantly influences the total pressure of the single-width wave on the dam surface. Based on the research results, the single-width wave total pressure prediction method is constructed under different first wave amplitudes in front of the dam, which can provide theoretical guidance and technical support for dam safety assessment and landslide-generated surge risk assessment. [ABSTRACT FROM AUTHOR]

Space-time adaptive processing (STAP) is a fundamental topic in airborne radar applications due to its clutter suppression ability. Reduced-dimension (RD)-STAP can release the requirement of the number of training samples and reduce the computational load from traditional STAP, which attracts much attention. However, under the situation that training samples are severely deficient, RD-STAP will become poor like the traditional STAP. To enhance RD-STAP performance in such cases, this paper develops a novel RD-STAP algorithm using random matrix theory (RMT), RMT-RD-STAP. By minimizing the output clutter-plus-noise power, the estimate of the inversion of clutter plus noise covariance matrix (CNCM) can be obtained through optimally manipulating its eigenvalues, thus producing the optimal STAP weight vector. Specifically, the clutter-related eigenvalues are estimated according to the clutter-related sample eigenvalues via RMT, and the noise-related eigenvalue is optimally selected from the noise-related sample eigenvalues. It is found that RMT-RD-STAP significantly outperforms the RD-STAP algorithm when the RMB rule cannot be satisfied. Theoretical analyses and numerical results demonstrate the effectiveness and the performance advantages of the proposed RMT-RD-STAP algorithm. [ABSTRACT FROM AUTHOR]

Reasonable building height distribution in urban residential areas is conducive to smoother vertical airflow exchange and promotes sustainable development. This paper studies the influence of building layouts on vertical ventilation in high-rise residential areas in Harbin, China, and discusses typical building layout objectives. The ideal area of 220 × 220 m was determined using statistical analysis and specification requirements, and seven typical layouts were defined based on the distribution of building heights. The computation fluid dynamics (CFD) simulation was verified using wind tunnel testing to improve the accuracy of the Phoenics simulation software. Wind speed, wind pressure, and the Universal Thermal Climate Index (UTCI) in residential areas distributed at different heights were analyzed and evaluated. The results indicated that the Phoenics simulation parameter settings, verified via wind tunnel testing, could achieve reasonable simulation results and different height distribution modes had an impact on the changes in wind speed and wind pressure. The equal-height layout that conformed to the row spacing of the buildings and the layout of taller buildings on the east side could provide higher comfort, and did not require enclosed and downwind layouts. This research can inform the green and livable design of residential buildings and provide a new perspective for the construction of high-rise residential areas in cold cities. [ABSTRACT FROM AUTHOR]

CeO2 nanosphere-supported nickel catalysts were prepared by the wetness impregnation method and employed for hydrogen production from glycerol steam reforming. The dried catalyst precursors were either reduced by H2 after thermal calcination or reduced by H2 directly without calcination. The catalysts that were reduced by H2 without calcination achieved a 95% glycerol conversion at a reaction temperature of only 475 °C, and the catalytic stability was up to 35 h. However, the reaction temperature required of catalysts reduced by H2 with calcination was 500 °C, and the catalysts was rapidly inactivated after 25 h of reaction. A series of physicochemical characterization revealed that direct H2 reduction without calcination enhanced the concentration of oxygen vacancies. Thus, the nickel dispersion was improved, the nickel nanoparticle size was reduced, and the reduction of nickel was increased. Moreover, the high concentration of oxygen vacancy not only contributed to the increase of H2 yield, but also effectively reduced the amount of carbon deposition. The increased active nickel surface area and oxygen vacancies synergistically resulted in the superior catalytic performance for the catalyst that was directly reduced by H2 without calcination. The simple, direct hydrogen reduction method remarkably boosts catalytic performance. This strategy can be extended to other supports with redox properties and applied to heterogeneous catalytic reactions involving resistance to sintering and carbon deposition. [ABSTRACT FROM AUTHOR]

The article titled "A Novel Drug Self-Delivery System from Fatty Alcohol Esters of Tranexamic Acid for Venous Malformation Sclerotherapy" has been retracted by the Pharmaceutics Editorial Office. The authors of the article raised concerns about scientific and image errors after its publication. An investigation conducted by the Editorial Office and Editorial Board confirmed the presence of errors in the figures, incorrect association of subfigures to experimental animals, and writing errors in the Material and Method section. Due to the inability to confirm the reliability of the findings, the article has been retracted according to MDPI's retraction policy. The retraction was approved by the Editor-in-Chief of the journal Pharmaceutics, and the authors agreed to the retraction. [Extracted from the article]

Panax ginseng is a famous herbal medicine widely used in Asia. Ginsenosides have been identified as the principle active ingredients for Panax ginseng's biological activity, among which ginsenoside Rd (Rd) attracts extensive attention for its obvious neuroprotective activities. Here we investigated the effect of Rd on neurite outgrowth, a crucial process associated with neuronal repair. PC12 cells, which respond to nerve growth factor (NGF) and serve as a model for neuronal cells, were treated with different concentrations of Rd, and then their neurite outgrowth was evaluated. Our results showed that 10 μM Rd significantly increased the percentages of long neurite- and branching neurite-bearing cells, compared with respective controls. The length of the longest neurites and the total length of neurites in Rd-treated PC12 cells were much longer than that of respective controls. We also showed that Rd activated ERK1/2 and AKT but not PKC signalings, and inhibition of ERK1/2 by PD98059 or/and AKT by LY294002 effectively attenuated Rd-induced neurite outgrowth. Moreover, Rd upregulated the expression of GAP-43, a neuron-specific protein involved in neurite outgrowth, while PD98059 or/and LY294002 decreased Rd-induced increased GAP-43 expression. Taken together, our results provided the first evidence that Rd may promote the neurite outgrowth of PC12 cells by upregulating GAP-43 expression via ERK- and ARK-dependent signaling pathways. [ABSTRACT FROM AUTHOR]

Venous malformation (VM), which causes severe damage to patients' appearance and organ function, is one of the most common vascular malformations. At present, many drugs in clinical treatment cause various adverse reactions. Herein, we synthesized cationic amphiphilic gelators (TA6, TA8, and TA9) by introducing saturated carbon chains of different lengths to tranexamic acid (TA), which could self-assemble into low-molecular-weight gels (LMWGs) as drug delivery carriers by hydrogen bonds, van der Waals forces, and hydrophobic interactions. The rheological properties, gelation driving force and drug release profiles of TA6, TA8, and TA9 hydrogels were characterized, and the results indicated that the hydrogels prepared in this study possessed the typical characteristics of a gel and could release drugs slowly. More importantly, the TA9 gelator showed significant pharmacological activity, in that it served as both an active drug compound and a drug carrier. The in vitro experiments demonstrated that TA9 induced HUVECs death and hemolysis by destroying cell membranes in a dose-dependent manner, and caused cell death and hemolysis at a concentration of 0.09 µM/mL. Meanwhile, we found TA9 could interact not only with fibrinogen, but also with other endogenous molecules in the blood. After the administration of TA9 hydrogel for 15 days, macroscopic imaging and histological evaluation in mice and rabbits displayed obvious thrombi, inflammatory reactions, and venous embolization, indicating that the mechanism of the TA9 hydrogel in treating VM was involved in two processes. Firstly, the TA9 hydrogel relied on its mechanical strength to physically block veins and continuously release TA9, in situ, for targeted therapy. Then, TA9 destroyed endothelial cells and damaged venous walls critically, causing thrombi. Most excitingly, TA9 was hydrolyzed to TA by enzymes that inhibited the degradation of thrombi by plasmin to prolong the embolization time and to promote venous fibrosis. Compared with other clinically available sclerosants, the degradation of TA9 also empowered a better biocompatibility and biodegradability for the TA9 hydrogel. In conclusion, we synthesized a potentially safe and effective derivative of TA and developed a low-molecular-weight gel as a self-delivery system for TA in treating VM. [ABSTRACT FROM AUTHOR]

Passages between buildings comprise the airflow path through the buildings, and the wind passage is often studied in terms of two buildings located parallel or at a certain angle. From the perspective of urban areas, the wind passage can be considered the series connection of all local wind passages between each row of buildings. Whether the central axis of each local wind passage is collinear or not, the wind passages of the building array can be summarized as distorted and streamlined types. Large-eddy simulations (LESs) are employed to assess the impacts of the above two wind passage types on the airflow and drag characteristics. The mean, unsteady flow fields and the drag distributions are discussed to assess the effects of wind passages types. Span-wise airflow was found in the wake region in the case of distorted wind passages (DWP), whereas the recirculating vortices dominated the wake region for the case of streamlined wind passages (SWP). Span-wise airflow enhanced the mean stream-wise velocity U and span-wise velocity U in the wake region, decreased U in the wind passage region, and increased dispersive stress 〈 V ˜ 2 〉 and 〈 U ˜ 2 〉 within the urban canopy and the peak Reynolds stress above the urban canopy. Further, it strengthened the individual drag forces of buildings and the fluctuations of span-wise and stream-wise individual drag forces. The air of DWP penetrated deeper than SWP. These findings provide theory and data support for better design of wind passages between buildings and may serve as a foundation for urban design and planning. [ABSTRACT FROM AUTHOR]

Steam reforming of glycerol to produce hydrogen is considered to be the very promising strategy to generate clean and renewable energy. The incipient-wetness impregnation method was used to load Ni on the reducible carrier TiO2 (P25). In the process of catalyst preparation, the interaction and electronic effect between metal Ni and support TiO2 were adjusted by changing the calcination temperature, and then the activity and hydrogen production of glycerol steam reforming reaction (GSR) was explored. A series of modern characterizations including XRD, UV-vis DRS, BET, XPS, NH3-TPD, H2-TPR, TG, and Raman have been applied to systematically characterize the catalysts. The characterization results showed that the calcination temperature can contribute to varying degrees of influences on the acidity and basicity of the Ni/TiO2 catalyst, the specific surface area, together with the interaction force between Ni and the support. When the Ni/TiO2 catalyst was calcined at 600 °C, the Ni species can be produced in the form of granular NiTiO3 spinel. Consequently, due to the moderate metal–support interaction and electronic activity formed between the Ni species and the reducible support TiO2 in the NiO/Ti-600C catalyst, the granular NiTiO3 spinel can be reduced to a smaller Ni0 at a lower temperature, and thus to exhibit the best catalytic performance. [ABSTRACT FROM AUTHOR]

The bacterial cell division protein, FtsZ, has been identified as a target for antimicrobial development. Derivatives of 3-methoxybenzamide have shown promising activities as FtsZ inhibitors in Gram-positive bacteria. We sought to characterise the activity of five difluorobenzamide derivatives with non-heterocyclic substituents attached through the 3-oxygen. These compounds exhibited antimicrobial activity against methicillin resistant Staphylococcus aureus (MRSA), with an isopentyloxy-substituted compound showing modest activity against vancomycin resistant Enterococcus faecium (VRE). The compounds were able to reverse resistance to oxacillin in highly resistant clinical MRSA strains at concentrations far below their MICs. Three of the compounds inhibited an Escherichia coli strain lacking the AcrAB components of a drug efflux pump, which suggests the lack of Gram-negative activity can partly be attributed to efflux. The compounds inhibited cell division by targeting S. aureus FtsZ, producing a dose-dependent increase in GTPase rate which increased the rate of FtsZ polymerization and stabilized the FtsZ polymers. These compounds did not affect the polymerization of mammalian tubulin and did not display haemolytic activity or cytotoxicity. These derivatives are therefore promising compounds for further development as antimicrobial agents or as resistance breakers to re-sensitive MRSA to beta-lactam antibiotics. [ABSTRACT FROM AUTHOR]

Presently, there is a lack of effective blood-based biomarkers facilitating the diagnosis of hepatocellular carcinoma (HCC). Thus, we aimed to investigate novel methylation markers for HCC diagnosis, and explore relationships between biomarker methylation and clinicopathology of HCC. The methylation status of the SCAN domain containing three (SCAND3) and myosin 1g (Myo1g) genes in HCC cell lines and tissues were detected by digital droplet PCR. The serum SCAND3 and Myo1g methylation levels were analyzed in HCC-afflicted patients and unafflicted controls. The results indicated SCAND3 and Myo1g methylation were abnormally high in the HCC cell lines and tissues. The values of serum SCAND3, Myo1g, and SCAND3 + Myo1g methylation with respect to facilitating the detection, and early detection of HCC were better than for alpha-fetoprotein (AFP) alone. Furthermore, when we combined SCAND3 + Myo1g with AFP, a high sensitivity and specificity resulted. Notably, in the AFP-negative HCC group, the methylation of SCAND3 and Myo1g also showed an excellent diagnostic performance. Besides this, a high serum SCAND3 methylation level was an independent risk factor for predicting portal vein tumor thrombus (PVTT) in HCC patients (OR = 4.746, p = 0.013). Finally, SCAND3 and Myo1g enhanced the HCC diagnostics as noninvasive serum methylation biomarkers, and the SCAND3 methylation status effectively indicated HCC accompanied by PVTT. [ABSTRACT FROM AUTHOR]

Poly(l-lactic acid)/ethylene propylene diene monomer/organic montmorillonite (PLLA/EPDM/OMMT) samples were melt-compounded and then processed into sheets via two routes, namely, compression-molding and calendering. Tensile performance, morphology, and thermal property of the samples were investigated. Tensile test showed that the incorporation of OMMT resulted in significant enhancement in the tensile ductility of the PLLA/EPDM samples. SEM observation revealed that EPDM domain size decreased largely with increasing OMMT loading, indicating the compatibility of OMMT with PLLA/EPDM blends. Moreover, the elongation at break, tensile yield strength, and modulus of the calendered samples were found to be much higher than those of the compression-molded samples. It can be attributed to the pre-oriented rigid amorphous fraction of PLLA matrix and pre-stretched EPDM phases in the calendered samples produced by the stretching/shearing effect of calendering. Compared to the spherical/ellipsoidal EPDM particles in the compression-molded samples, these stretched EPDM phases with higher aspect ratio in the calendered samples can be more effective to initiate craze, and terminate the craze growing to a crack along transversal direction. Therefore, the calendered samples show a better tensile ductility than the compression-molded ones. Moreover, annealing was carried out to increase the crystallinity of the samples. Tensile performance, morphology, and thermal property of the annealed samples were also systematically investigated. [ABSTRACT FROM AUTHOR]

Automation is an inevitable trend in the development of tunnel shotcrete machinery. Tunnel environmental perception based on 3D LiDAR point cloud has become a research hotspot. Current researches about the detection of tunnel point clouds focus on the completed tunnel with a smooth surface. However, few people have researched the automatic detection method for steel arches installed on a complex rock surface. This paper presents a novel algorithm to extract tunnel steel arches. Firstly, we propose a refined function for calibrating the tunnel axis by minimizing the density variance of the projected point cloud. Secondly, we segment the rock surface from the tunnel point cloud by using the region-growing method with the parameters obtained by analyzing the tunnel section sequence. Finally, a Directed Edge Growing (DEG) method is proposed to detect steel arches on the rock surface in the tunnel. Our experiment in the highway tunnels under construction in Changsha (China) shows that the proposed algorithm can effectively extract the points of the edge of steel arches from 3D LiDAR point cloud of the tunnel without manual assistance. The results demonstrated that the proposed algorithm achieved 92.1% of precision, 89.1% of recall, and 90.6% of the F-score. [ABSTRACT FROM AUTHOR]

A series of novel 3-aryl-4-hydroxy-2(5H) furanone-acrylate hybrids were designed and synthesized based on the natural butenolides and acrylates scaffolds. The structures of the prepared compounds were characterized by 1H-NMR, 13C-NMR and electrospray ionization mass spectrometry (ESI-MS), and the bioactivity of the target compounds against twelve phytopathogenic fungi was investigated. The preliminary in vitro antifungal activity screening showed that most of the target compounds had moderate inhibition on various pathogenic fungi at the concentration of 100 mg·L−1, and presented broad-spectrum antifungal activities. Further studies also indicated that compounds 7e and 7k still showed some inhibitory activity against Pestallozzia theae, Sclerotinia sclerotiorum and Gibberella zeae on rape plants at lower concentrations, which could be optimized as a secondary lead for further research. [ABSTRACT FROM AUTHOR]

Due to their excellent light transmission, heat resistance, corrosion resistance, high mechanical strength, and other characteristics, transparent materials have been widely used in emerging industries such as aviation, aerospace, microelectronics, interconnected communication, etc. Compared with the traditional mechanical processing and chemical processing of transparent materials, laser processing, with such characteristics as a high peak power, high energy density, and non-contact processing, has a lot of obvious advantages in processing efficiency and accuracy. In this paper, some of the recent research advancements concerning the laser processing of transparent materials are introduced in detail. Firstly, the basic mechanism of the interaction between the laser and material is briefly summarized on the time scale. The differences in principle between nanosecond, picosecond, and femtosecond pulse laser processing are analyzed. Then, the main technical means of the nanosecond laser processing of transparent materials are summarized. Next, the main application directions of the ultrafast laser processing of transparent materials are discussed, including the preparation of optical waveguide devices, periodic structure devices, micropores, and microchannels. Finally, this paper summarizes the prospects for the future development of laser processing transparent materials.

Recognition of unusual left-handed Z-DNA by specific binding of small molecules is crucial for understanding biological functions in which this particular structure participates. Recent investigations indicate that zinc cationic porphyrin (ZnTMPyP4) is promising as a probe for recognizing Z-DNA due to its characteristic chiroptical properties upon binding with Z-DNA. However, binding mechanisms of the ZnTMPyP4/Z-DNA complex remain unclear. By employing time-resolved UV-visible absorption spectroscopy in conjunction with induced circular dichroism (ICD), UV-vis, and fluorescence measurements, we examined the binding interactions of ZnTMPyP4 towards B-DNA and Z-DNA. For the ZnTMPyP4/Z-DNA complex, two coexisting binding modes were identified as the electrostatic interaction between pyridyl groups and phosphate backbones, and the major groove binding by zinc(II) coordinating with the exposed guanine N₇. The respective contribution of each mode is assessed, allowing a complete scenario of binding modes revealed for the ZnTMPyP4/Z-DNA. These interaction modes are quite different from those (intercalation and partial intercalation modes) for the ZnTMPyP4/B-DNA complex, thereby resulting in explicit differentiation between B-DNA and Z-DNA. Additionally, the binding interactions of planar TMPyP4 to DNA were also investigated as a comparison. It is shown that without available virtual orbitals to coordinate, TMPyP4 binds with Z-DNA solely in the intercalation mode, as with B-DNA, and the intercalation results in a structural transition from Z-DNA to B-ZNA. These results provide mechanistic insights for understanding ZnTMPyP4 as a probe of recognizing Z-DNA and afford a possible strategy for designing new porphyrin derivatives with available virtual orbitals for the discrimination of B-DNA and Z-DNA., Competing Interests: The authors declare no conflict of interest.

Panax ginseng is a famous herbal medicine widely used in Asia. Ginsenosides have been identified as the principle active ingredients for Panax ginseng's biological activity, among which ginsenoside Rd (Rd) attracts extensive attention for its obvious neuroprotective activities. Here we investigated the effect of Rd on neurite outgrowth, a crucial process associated with neuronal repair. PC12 cells, which respond to nerve growth factor (NGF) and serve as a model for neuronal cells, were treated with different concentrations of Rd, and then their neurite outgrowth was evaluated. Our results showed that 10 μM Rd significantly increased the percentages of long neurite- and branching neurite-bearing cells, compared with respective controls. The length of the longest neurites and the total length of neurites in Rd-treated PC12 cells were much longer than that of respective controls. We also showed that Rd activated ERK1/2 and AKT but not PKC signalings, and inhibition of ERK1/2 by PD98059 or/and AKT by LY294002 effectively attenuated Rd-induced neurite outgrowth. Moreover, Rd upregulated the expression of GAP-43, a neuron-specific protein involved in neurite outgrowth, while PD98059 or/and LY294002 decreased Rd-induced increased GAP-43 expression. Taken together, our results provided the first evidence that Rd may promote the neurite outgrowth of PC12 cells by upregulating GAP-43 expression via ERK- and ARK-dependent signaling pathways.