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AbstractMarine dredged-sediment(DS) is often transported through pipelines, where factors such as the solid volume concentration and transport rate can significantly influence the efficiency of the process. Inadequate selection of transport rates for a given solid volume concentration can lead to substantial energy losses. The pressure loss ΔPL or pressure loss gradient ΔPL/L are critical parameters for assessing energy loss during pipeline transport. In this study, large-scale indoor experiments on DS pipeline transport were conducted to investigate the effects of the cross-sectional mean flow velocity Vavg and solid concentration ϕ on the transport characteristics of DS. The results show that at higher solid volume concentrations, ΔPL/L increases rapidly with the square of Vavg and then plateaus, followed by a linear growth phase. In addition, a linear relationship is observed between lgf and lgVavg when the flow velocity is below critical velocity (Vavg)critical; above (Vavg)critical, the friction factor f stabilizes at f0. Formulas for calculating (Vavg)critical, f0 and ϕ were developed. Additionally, a method for determining the optimal transport velocity of DS at varying volume concentrations was established, enabling the identification of the most efficient flow velocity for DS pipeline transportation across different concentrations.HIGHLIGHTSPipeline model tests were conducted on marine dredged sediments.A formula for predicting pressure loss on the basis of solid concentration was derived.The impact of the solid concentration on the Darcy friction factor was determined.A method for determining the optimal transport velocity was established.Pipeline model tests were conducted on marine dredged sediments.A formula for predicting pressure loss on the basis of solid concentration was derived.The impact of the solid concentration on the Darcy friction factor was determined.A method for determining the optimal transport velocity was established. [ABSTRACT FROM AUTHOR]

In this paper, a fiber Bragg grating (FBG) temperature measurement method for intersatellite laser link is studied. Based on the analysis of the FBG temperature measurement method, the FBG sensing demodulation system is built to calibrate its wavelength and temperature parameters. The experimental data of temperature gradient monitoring are compared with the on-orbit real-time temperature data of a satellite's solar array measured by the thermistor to verify the temperature monitoring accuracy and stability of the FBG sensing demodulation system. The FBG sensing demodulation system and the thermistor temperature measurement system are compared under the same environmental conditions during the constant temperature period, the continuous heating phase and the natural cooling phase. The results show that during the constant temperature period, the temperature fluctuation range and standard deviation of the FBG sensing demodulation system are ±0.16 °C and 0.08 °C, respectively, which is significantly better than the performance of the thermistor temperature measurement system, whose temperature fluctuation range and standard deviation are ±5.92 °C and 1.08 °C, respectively. The temperature response speed of the former is significantly faster than that of the latter during the continuous heating phase and the natural cooling phase. [ABSTRACT FROM AUTHOR]

Abstract: A calix[4]arene functionized boron dipyrromethene (CBDP) was utilized as a charged fluorescent chromoionophore in ion optodes. The plasticized polyvinyl chloride (PVC) films containing CBDP and anion exchanger tridodecylmethylammonium chloride (TDMACl) exhibited reversible response to pH from 2 to 10. The fluorescence intensity of CBDP increases upon protonation due to the suppression of the photo induced electron transfer (PET) process between phenolate anion in calixarene and bodipy core. CBDP was applied to prepare anion and cation selective optodes based on co-extraction or ion-exchange mechanism. Optical sensors with the same fluorescent chromoionophore for four blood electrolytes, chloride ion, potassium ion, sodium ion, and calcium ion were prepared and allow the simultaneous measurements of multi analytes in biological samples by microplate reader. The concentrations of four electrolytes in rabbit plasma determined by the proposed optodes were consistent with the results obtained by conventional potentiometric methods, which suggests the possibilities for further applications of such optodes in clinical diagnosis. [Copyright &y& Elsevier]

A highly stable, long wavelength polarity sensitive probe, 8-nitrophenyl-3,5-dipiperidine-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (NPBDP), was developed for living cell imaging of intracellular lipid droplets by fluorescence microscopy. [ABSTRACT FROM AUTHOR]

A novel Fabry–Perot (F–P) interferometer model based on the ultra-small gradient-index (GRIN) fiber probe is investigated. The signal arm of the F–P interferometer is organically combined with the ultra-small GRIN fiber probe to establish the theoretical model of the novel F–P interferometer. An interferometer experimental system for vibration measurements was built to measure the performance of the novel F–P interferometer system. The experimental results show that under the given conditions, the output voltage of the novel interferometer is 3.9 V at the working distance of 0.506 mm, which is significantly higher than the output voltage 0.48 V of the single-mode fiber (SMF) F–P interferometer at this position. In the range of 0.1–2 mm cavity length, the novel interferometer has a higher output voltage than an SMF F–P interferometer. Therefore, the novel F–P interferometer is available for further study of the precise measurement of micro vibrations and displacements in narrow spaces. [ABSTRACT FROM AUTHOR]

Abstract Differences in trophic status can lead to different water quality and sediment geochemistry characteristics, influencing antimony (Sb) mobility in sediments and its release into the water column. In this study, seasonal sampling was conducted in algal- and macrophyte-dominated zones of Lake Taihu, China. High-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) techniques were used to measure soluble Sb and DGT-labile Sb in the sediment-water profiles at a 4 mm vertical resolution. Results showed that total Sb in sediments from the two zones were on average 3.50 mg/kg and 3.21 mg/kg in the algal- and macrophyte-dominated zones, respectively, with the residual fraction being 96.3% and 95.4% of the total Sb contents in the two zones. In winter, soluble Sb concentrations in both zones increased. This was probably due to the oxidation of Sb(III) to Sb(V) by Mn and Fe oxides. In summer and autumn, soluble Sb concentrations in the algal-dominated region remained low. This is attributed to the dominance of insoluble Sb(III) in sediments under anoxic conditions under eutrophic environments. In contrast, soluble Sb concentrations in the macrophyte-dominated zone were significantly high in summer and were 4.15-times higher than limits set by the World Health Organization (WHO). This likely resulted from the photochemical and rhizospheric oxidation of insoluble Sb(III) compounds. It is suggested that Sb contamination in the sediment-water system of the macrophyte-dominated zone deserves additional attention. Highlights • Antimony (Sb) mobility differed in algae- and macrophyte-dominated (MD) regions. • Photochemical and rhizospheric oxidation increased Sb mobility in the MD region in summer. • Mn and Fe oxide oxidation increased Sb mobility in two regions during winter. • Sb mobilization manifested mainly in the transition between Sb(III) and Sb(V). [ABSTRACT FROM AUTHOR]

Abstract Studies of dredging effectiveness, especially the ones that last for several years, are scarce. In this study, we evaluated effectiveness of dredging performed for six years on controlling cobalt (Co), zinc (Zn), and nickel (Ni) contamination of sediments. High-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) methods were applied to analyze the non-dredged and post-dredging sediments. The soluble and DGT-labile Co and Ni content declined by 22% and 44% (soluble) and by 16% and 26% (labile) in April, July and October in the post-dredging region. In contrast, their concentrations increased by 105% and 9% (soluble) and 322% and 27% (labile) in January. These changes in the dredging effects were caused by the corresponding changes in the reducible and residual fractions of Co and the residual fraction of Ni in sediments in the dredged site, respectively. Soluble and DGT-labile Zn decreased on average by 23% and 29% in July and October and increased on average by 151% and 52% in April and January in the post-dredging region. The different Zn mobility in the post-dredging region was controlled by the reducible fraction of Zn. The results revealed positive influence of dredging engineering in summer, autumn and/or spring and negative one in winter. Therefore, an accurate assessment of dredging effectiveness should take its seasonal variation into consideration. Graphical abstract Image 1 Highlights • Dredging effects change during the different seasons as reflected by soluble and labile concentrations. • Dredging was most effective in April, July and October and had a negative effect in January. • Efficacy of Co was affected by the reducible and residual fractions in sediments. • Efficacies of Zn and Ni were respectively affected by reducible and residual fractions. [ABSTRACT FROM AUTHOR]

• A new DGT can simultaneous 2-D imaging of three types of analytes by LA-ICP-MS. • The LA-ICP-MS method provides good analytical precision for 17 elements. • The hybrid PO-DGT sensor allows simultaneous 2-D imaging of O 2 and 17 elements. A new diffusive gradients in thin films technique (HR-ZCA DGT) was developed for simultaneous two-dimensional (2-D) chemical imaging of sulfides, metallic cations and oxyanions (S, Cd, Co, Fe, Cu, Mn, Ni, Pb, Zn, As, Cr, Mo, Sb, Se, V, P and W) at the submillimeter scale, combined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. A novel binding gel was prepared using a double precipitation method with AgI and zirconium oxide (Zr-oxide) deposited sequentially on a preformed Chelex-100 resin gel. A good linear relationship was observed (R 2>0.99) between mass accumulation of the 17 assessed elements on the binding gel and the corresponding standardized laser ablation signals (signals of elements divided by signals of internal standard 13C), proving the feasibility of LA-ICP-MS analysis. Good analytical precision (RSD<12 %) was achieved for all 17 elements. A hybrid sensor comprising the novel DGT binding gel overlying an O 2 planar optrode was then tested in sediments to evaluate the dynamics of O 2 and multiple elements. Results showed that the mobility of As, P and W were controlled by precipitation/dissolution processes with Fe/Mn oxides. V, Co, Ni, Zn, Mo, Cd and Sb were released at the sediment surface with the oxidation of iron sulfides. [ABSTRACT FROM AUTHOR]

Background: Abdominal aortic aneurysm (AAA) is a degenerative disease that causes health problems in humans. However, there are no effective drugs for the treatment of AAA. Artemisia annua L. ( A. annua ) is a traditional herbal that has been widely used in cardiovascular disease. Based on network pharmacology and molecular docking technology, this study predicted the practical components and potential mechanisms of A. annua inhibiting the occurrence and development of AAA. Methods: The main active ingredients and targets of A. annua were screened through the TCMSP database; the GeneCards, OMIM, PharmGkb, and TTD databases were used to search for the targeted genes of AAA and map them to the targets of the active ingredients to obtain the active ingredient therapy of A. annua . The targets of AAA were to construct a protein interaction network through the STRING platform. R software was used to carry out the enrichment analysis of GO and KEGG for relevant targets, and Cytoscape was used to construct the active ingredient-target network prediction model of A. annua . Finally, AutoDock Vina was used to verify the results of the active ingredients and critical targets. Results: The main active ingredients obtained from A. annua for the treatment of AAA include quercetin, luteolin, kaempferol, isorhamnetin, and artemetin, as well as 117 effective targets, including RELA, MAPK14, CCND1, MAPK1, AKT1, MYC, MAPK8, TP53, ESR1, FOS, and JUN. The 11 targeted genes might play a key role in disease treatment. Enriched in 2115 GO biological processes, 159 molecular functions, 56 cellular components, and 156 KEGG pathways, inferred that its mechanism of action might be related to PI3K-Akt signaling pathway, fluid shear stress, atherosclerosis, and AGE-RAGE signaling pathway. Molecular docking results showed that the top five active components of A. annua had a good affinity for core disease targets and played a central role in treating AAA. The low binding energy molecular docking results provided valuable information for the development of drugs to treat AAA. Conclusion: Therefore, A. annua may have multiple components, multiple targets, and multiple signaling pathways to play a role in treating AAA. A. annua may have the potential to treat AAA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jia, Jing, Wang, Cheng, Fu, Chu, Yang, Jiang and Xin.)

A novel Fabry⁻Perot (F⁻P) interferometer model based on the ultra-small gradient-index (GRIN) fiber probe is investigated. The signal arm of the F⁻P interferometer is organically combined with the ultra-small GRIN fiber probe to establish the theoretical model of the novel F⁻P interferometer. An interferometer experimental system for vibration measurements was built to measure the performance of the novel F⁻P interferometer system. The experimental results show that under the given conditions, the output voltage of the novel interferometer is 3.9 V at the working distance of 0.506 mm, which is significantly higher than the output voltage 0.48 V of the single-mode fiber (SMF) F⁻P interferometer at this position. In the range of 0.1⁻2 mm cavity length, the novel interferometer has a higher output voltage than an SMF F⁻P interferometer. Therefore, the novel F⁻P interferometer is available for further study of the precise measurement of micro vibrations and displacements in narrow spaces.

Continuous fluorescence imaging of intracellular ions in various spectral ranges is important for biological studies. In this paper, fluorescent calcium-selective nanospheres, including calix[4]arene-functionalized bodipy (CBDP) or 9-(diethylamino)-5-[(2-octyldecyl)imino]benzo[a]phenoxazine (ETH 5350) as the chromoionophore, were prepared to demonstrate intracellular calcium imaging in visible or near-IR regions, respectively. The fluorescence of the nanospheres was controlled by the chromoionophore, and thus the spectral range for detection was adjustable by choosing the proper chromoionophore. The response time of the nanospheres to calcium was typically 1 s, which allowed accurate measurement of intracellular calcium. These nanospheres were loaded into cells through free endocytosis and exhibited fluorescence for 24 h, and their intensity was correlated with the elevation of intracellular calcium upon stimulation. The successful demonstration of calcium imaging by use of ion-selective nanospheres within two spectral ranges in 24 h supported that these nanospheres could be applied for continuous imaging of intracellular ions with adjustable spectra.