32 research outputs found

    Inverse design for material anisotropy and its application for a compact X-cut TFLN on-chip wavelength demultiplexer

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    Inverse design focuses on identifying photonic structures to optimize the performance of photonic devices. Conventional scalar-based inverse design approaches are insufficient to design photonic devices of anisotropic materials such as lithium niobate (LN). To the best of our knowledge, this work proposes for the first time the inverse design method for anisotropic materials to optimize the structure of anisotropic-material based photonics devices. Specifically, the orientation dependent properties of anisotropic materials are included in the adjoint method, which provides a more precise prediction of light propagation within such materials. The proposed method is used to design ultra-compact wavelength division demultiplexers in the X-cut thin-film lithium niobate (TFLN) platform. By benchmarking the device performances of our method with those of classical scalar-based inverse design, we demonstrate that this method properly addresses the critical issue of material anisotropy in the X-cut TFLN platform. This proposed method fills the gap of inverse design of anisotropic materials based photonic devices, which finds prominent applications in TFLN platforms and other anisotropic-material based photonic integration platforms

    Analysis of the Correlation and Regional Distribution of Plastic Waste Pollution

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    Plastic has brought great convenience to people’s lives, but it has also brought severe environmental pollution to the world. It is almost impossible to break down entirely in nature, and plastic waste, whether in rivers, oceans, or on land, can persist in the environment for centuries. The problem of plastic waste disposal has caused worldwide concern. It is necessary to reduce the production of plastic products through global cooperation effectively. However, achieving this goal will also involve some unexpected issues, such as controlling the adverse economic impact of plastics, and the rationality and fairness of the distribution of responsibilities between different countries. This paper collects massive data and takes China as an example to study the impact of plastic output reduction on China’s Express industry and the plastics manufacturing industry using multivariate regression. This paper summarizes the positive and negative effects of plastic waste reduction. Given the distribution and management of national and regional plastic waste responsibilities, the global carbon emission rights distribution method is used for reference. The comprehensive index allocation method is used to deal with the problem of both fairness and efficiency relatively. What is more, based on the conclusions, this paper also provides suggestions for a global joint response to plastic waste

    Effects of Filler–Bitumen Ratio and Mineral Filler Characteristics on the Low-Temperature Performance of Bitumen Mastics

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    This study analyzed the effects of the filler–bitumen interaction of the content and the meso powder characteristics of the mineral filler on the low-temperature performance of bitumen mastics. Control strategies for the mineral filler content (filler–bitumen ratio (RFB)) were also determined. Panjin #90 bitumen and styrene–butadiene–styrene polymer-modified bitumen were used in the experiment. Four kinds of limestone powder were used, all of which satisfy the Chinese standard for powder particle size but exhibit different meso characteristics. Each kind of limestone powder was used to prepare bitumen mastic samples under five different RFBs. The meso voids in the unit mass (Vg) of the four kinds of mineral filler were tested on the basis of the principle of the Rigden void ratio. The fixed bitumen–free bitumen ratio in the bitumen mastic samples was determined using Vg, bitumen density, and RFB. The low-temperature cohesive strength of the bitumen mastics was used as the control index for critical failure, whereas variation rates of bending creep stiffness at low temperature were used as the control index for fatigue failure. Results showed that the effects of the filler–bitumen interaction of the content and the meso characteristics of the mineral filler are significant and such effects are determined by the fixed bitumen–free bitumen ratio. The optimal fixed bitumen–free bitumen ratio in the bitumen mastics under two low-temperature conditions (−30 °C and −10 °C) can be determined on the basis of the influence of the fixed bitumen–free bitumen ratio on the critical and the failure control indices. Moreover, RFB can be obtained through reverse calculation. The mineral filler content can therefore be precisely controlled, which is crucial for the rational use of mineral filler and for the improvement of the pavement performance of bitumen mastics at low temperatures

    Analysis of the Effects of Ageing on the Cohesive Strength of Polymer-Modified Bitumen at Low Temperatures

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    The decay law on the ageing process of the cohesive strength of styrene-butadiene-styrene(SBS)- and polyethylene(PE)-modified bitumens at low temperatures was investigated. The rotated-thin-film oven test was used to age the two types of polymer-modified bitumens. The cohesive strengths at different low-temperature conditions were tested quantitatively according to technology for testing the low-temperature cohesive strength of bitumen. The decay curve of bitumen low-temperature cohesive strengths was drawn, and the embrittlement time of bitumen at different ageing states was obtained according to the decay curve. Results showed that ageing time definitely influenced the attenuation degree of the low-temperature cohesive strength of the two types of polymer-modified bitumens and influenced the appearance of the low-temperature cohesive strength peak, i.e., the bitumen embrittlement time, which advanced after ageing. The lightweight components of polymer-modified bitumen were lost after ageing. The bitumen embrittlement time was advanced, and the sharp attenuation of the low-temperature cohesive strength of bitumen appeared. In the future, bitumen antiageing technology and lighter part pre-supplement technology should be studied in-depth

    Effect of Zero Water Exchange Systems for <i>Litopenaeus vannamei</i> Using Sponge Biocarriers to Control Inorganic Nitrogen and Suspended Solids Simultaneously

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    The traditional shrimp farming mode, which mainly uses water exchange to dilute toxic nitrogenous compounds, not only brings risks of disease infections and outbreaks but also results in waste of water resources and has a negative impact on the environment. In this study, zero water exchange systems for Litopenaeus vannamei were constructed by using sponge biocarriers with precultured biofilms (SBBFs), and the effect of SBBFs on controlling inorganic nitrogen, suspended solids and on the performance of L. vannamei was determined. The experiment consisted of four treatments: (1) SBC (control, SB 5% (v/v) + aeration); (2) SBBF2.5a (SBBF 2.5% (v/v) + aeration); (3) SBBF5a (SBBF 5% (v/v) + aeration); and (4) SBBF5 (SBBF 5% (v/v)). The results showed that the concentrations of TAN and NO2−-N in the SBBF treatments were significantly lower than those in the SBC treatments, while the SBBF treatments registered higher NO3−-N concentrations. After the adsorbates were removed by regular cleaning to regenerate the adsorption capacity of the SBs, the turbidity was reduced by 47.8%~71.5%. The shrimp grown in the SBBF treatments exhibited a higher mean final weight, survival and productivity than those grown in the SBC treatments. This work found that the use of SBBFs can maintain the low levels of TAN, NO2−-N and suspended solids while improving the performance of the L. vannamei under the strict requirement of zero water exchange

    Resveratrol attenuates intestinal epithelial barrier dysfunction via Nrf2/HO‐1 pathway in dextran sulfate sodium‐induced Caco‐2 cells

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    Abstract Introduction The intestinal tract serves as an innate barrier, safeguarding the internal milieu from microorganisms and toxins. Various intestinal inflammatory diseases have a strong association with intestinal barrier dysfunction. The primary functional cells within the intestinal tract, intestinal epithelial cells (IECs) and their tight junctions (TJs), are crucial in preserving the integrity of this mechanical barrier. Resveratrol (Res), a plant‐derived phenolic compound, exhibits a range of health‐promoting benefits attributed to its anti‐inflammatory properties. This study aims to examine Res's efficacy in bolstering IECs barrier function. Methods Dextran sulfate sodium (DSS) was employed to induce barrier dysfunction in IECs. Inflammatory cytokines in supernatants (interleukin [IL]‐6, IL‐1ÎČ, tumor necrotic factor [TNF]‐α, and IL‐10) were quantified via enzyme‐linked immunosorbent assay (ELISA). Then we assessed monolayer integrity using transepithelial electrical resistance (TEER). TJ protein expression (zonula occludens [ZO]‐1 and Occludin) in IECs was evaluated through immunofluorescence and Western blot analysis. Network pharmacology helped identify the biological processes, signaling pathways, and key targets involved in Res's mitigation of DSS‐induced IECs barrier dysfunction. The efficacy of the primary target was further corroborated using Western blot. Results Res was shown to increase cell viability and IL‐10 expression while reducing TNF‐α, IL‐6, and IL‐1ÎČ levels, thus mitigating the inflammatory response. It enhanced TEER values and upregulated TJ protein expression (ZO‐1 and Occludin). Network pharmacology revealed that Res potentially targets the NFE2L2 (nuclear factor erythroid‐2‐related factor 2, Nrf2), a vital antioxidant factor. Significantly, Res augmented Nrf2 and heme oxygenase 1 (HO‐1) protein levels, counteracting oxidative stress in the IECs barrier dysfunction model. Conclusion Overall, our findings suggested that Res ameliorated DSS‐induced IECs barrier dysfunction by activating Nrf2/HO‐1 pathway, showcasing significant therapeutic potential in the early stages of colitis

    Petrogenesis of Middle Triassic Adakite-like Intrusions in the Asiha Orogenic Gold Deposit, East Kunlun Orogenic Belt, China

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    The East Kunlun Orogenic Belt is considered as one of the important gold mineralization regions in the Tethys tectonic domain. These orogenic gold deposits are related to intermediate-acid intrusions formed at the end of Paleo-Tethys evolution, but the petrogenesis is controversial. This paper presents a new study on the geochemistry of zircon U-Pb, O, S, and Pb isotopic compositions of Asiha quartz diorite, granite porphyry, and sulfides. The geochemical features of quartz diorite and granite porphyry are consistent with the modern adakite, with high content of Sr but low content of Y, Yb, and MgO. Magmatic zircons from these two types of intrusion yielded U-Pb ages of 238.4 ± 1.4 Ma and 240 ± 1.7 Ma, respectively. The high O isotopic composition of Asiha complex may reflect that crust or crustal derivates were incorporated into the magmatic melt, and the Pb isotope characteristics indicates a lower crust origin. The ÎŽ34S values of pyrites range from 4.9‰ to 11.6‰. This study infers that the Asiha complex perhaps formed by partial melting of the Paleo-Tethys subducted oceanic crust with seafloor sediments and is markedly different from the traditional adakite. Asiha deposit is an orogenic gold deposit related to adakite-like rocks, which formed in Triassic in the East Kunlun Orogenic Belt

    LUBAC promotes angiogenesis and lung tumorigenesis by ubiquitinating and antagonizing autophagic degradation of HIF1α

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    Abstract Hypoxia-inducible factor 1 (HIF1) is critically important for driving angiogenesis and tumorigenesis. Linear ubiquitin chain assembly complex (LUBAC), the only known ubiquitin ligase capable of catalyzing protein linear ubiquitination to date, is implicated in cell signaling and associated with cancers. However, the role and mechanism of LUBAC in regulating the expression and function of HIF1α, the labile subunit of HIF1, remain to be elucidated. Herein we showed that LUBAC increases HIF1α protein expression in cultured cells and tissues of human lung cancer and enhances HIF1α DNA-binding and transcriptional activities, which are dependent upon LUBAC enzymatic activity. Mechanistically, LUBAC increases HIF1α stability through antagonizing HIF1α decay by the chaperone-mediated autophagy (CMA)-lysosome pathway, thereby potentiating HIF1α activity. We further demonstrated that HIF1α selectively interacts with HOIP (the catalytic subunit of LUBAC) primarily in the cytoplasm. LUBAC catalyzes linear ubiquitination of HIF1α at lysine 362. Linear ubiquitination shields HIF1α from interacting with heat-shock cognate protein of 70 kDa and lysosome-associated membrane protein type 2 A, two components of CMA. Consequently, linear ubiquitination confers protection against CMA-mediated destruction of HIF1α, increasing HIF1α stability and activity. We found that prolyl hydroxylation is not a perquisite for LUBAC’s effects on HIF1α. Functionally, LUBAC facilitates proliferation, clonogenic formation, invasion and migration of lung cancer cells. LUBAC also boosts angiogenesis and exacerbates lung cancer growth in mice, which are greatly compromised by inhibition of HIF1α. This work provides novel mechanistic insights into the role of LUBAC in regulating HIF1α homeostasis, tumor angiogenesis and tumorigenesis of lung cancer, making LUBAC an attractive therapeutic target for cancers
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