A built‐in electric field in electrocatalyst can significantly accumulate higher concentration of NO3− ions near electrocatalyst surface region, thus facilitating mass transfer for efficient nitrate ...removal at ultra‐low concentration and electroreduction reaction (NO3RR). A model electrocatalyst is created by stacking CuCl (111) and rutile TiO2 (110) layers together, in which a built‐in electric field induced from the electron transfer from TiO2 to CuCl (CuCl_BEF) is successfully formed . This built‐in electric field effectively triggers interfacial accumulation of NO3− ions around the electrocatalyst. The electric field also raises the energy of key reaction intermediate *NO to lower the energy barrier of the rate determining step. A NH3 product selectivity of 98.6 %, a low NO2− production of <0.6 %, and mass‐specific ammonia production rate of 64.4 h−1 is achieved, which are all the best among studies reported at 100 mg L−1 of nitrate concentration to date.
An electrocatalyst is created by stacking CuCl (111) and rutile TiO2 (110) layers together. A built‐in electric field induced from the electron transfer from TiO2 to CuCl (CuCl_BEF) is thus formed, which triggers interfacial accumulation of NO3− ions around the electrocatalyst. A NH3 product selectivity of 98.6 %, a low NO2− production of <0.6 %, and mass‐specific ammonia production rate of 64.4 h−1 is achieved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Nitrate electrocatalytic reduction (NO3RR) for ammonia production is a promising strategy to close the N‐cycle from nitration contamination, as well as an alternative to the Haber–Bosch process with ...less energy consumption and carbon dioxide release. However, current long‐term stability of NO3RR catalysts is usually tens of hours, far from the requirements for industrialization. Here, symmetry‐broken Cusingle‐atom catalysts are designed, and the catalytic activity is retained after operation for more than 2000 h, while an average ammonia production rate of 27.84 mg h−1 cm−2 at an industrial level current density of 366 mA cm−2 is achieved, obtaining a good balance between catalytic activity and long‐term stability. Coordination symmetry breaking is achieved by embedding one Cu atom in graphene nanosheets with two N and two O atoms in the cis‐configuration, effectively lowering the coordination symmetry, rendering the active site more polar, and accumulating more NO3− near the electrocatalyst surface. Additionally, the cis‐coordination splits the Cu 3d orbitals, which generates an orbital‐symmetry‐matched π‐complex of the key intermediate *ONH and reduces the energy barrier, compared with the σ‐complex generated with other catalysts. These results reveal the critical role of coordination symmetry in single‐atom catalysts, prompting the design of more coordination‐symmetry‐broken electrocatalysts toward possible industrialization.
A coordination‐symmetry‐breaking Cusingle‐atom catalyst enables a good balance between catalytic activity and long‐term stability in nitrate electroreduction to ammonia. The catalytic activity is retained after operation for more than 2000 h, while an average ammonia production rate of 27.84 mg h−1 cm−2 at an industrial level current density of 366 mA cm−2 is achieved.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Hepatocellular carcinoma (HCC), the major form of liver cancer, has shown increasing incidence and poor prognosis. Adipose tissue is known to function in energy storage and metabolism regulation by ...the secretion of adipokines. Circular RNAs (circRNAs), a novel type of noncoding RNA, have recently been recognized as key factors in tumor development, but the role of exosome circRNAs derived from adipose tissues has not been defined yet. Here, adipose-secreted circRNAs were found to regulate deubiquitination in HCC, thus facilitating cell growth. It was observed that exosome circ-deubiquitination (circ-DB) is upregulated in HCC patients with higher body fat ratios. Moreover, in vitro and in vivo studies showed that exo-circ-DB promotes HCC growth and reduces DNA damage via the suppression of miR-34a and the activation of deubiquitination-related USP7. Finally, the results showed that the effects of adipose exosomes on HCC cells can be reversed by knockdown of circ-DB. These results indicate that exosome circRNAs secreted from adipocytes promote tumor growth and reduce DNA damage by suppressing miR-34a and activating the USP7/Cyclin A2 signaling pathway.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Metastasis is a crucial reason for the poor prognosis of gastric cancer. Angiogenesis is closely associated with tumor invasion and metastasis. Cancer-derived exosomes play an important role in the ...establishment of the tumor microenvironment. In this study, exosomes were isolated by sequential differential centrifugation, and they were verified by transmission electron microscopy. Changes in the biological behavior of human umbilical vein endothelial cells were evaluated with downstream cellular functional experiments. The RNA and protein levels of the miRNA target gene were determined by real-time qPCR and western blotting. A mouse xenograft model was adopted to evaluate the correlation between exosome-derived miR-130a and tumor growth in vivo. We demonstrated that exosomes delivered miR-130a from gastric cancer cells into vascular cells to promote angiogenesis and tumor growth by targeting c-MYB both in vivo and in vitro. miR-130a packaged in exosomes secreted from cancer cells acts as a driver of angiogenesis. Therefore, miR-130a might be a potential biomarker for monitoring the activity of gastric cancer. In addition, suppressing the expression or blocking the transmission of these exosomes might be a novel antiangiogenic therapeutic strategy for gastric cancer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cancer‐related cachexia is a metabolic syndrome characterized by a wasting disorder of adipose and skeletal muscle and is accompanied by body weight loss and systemic inflammation. The treatment ...options for cancer cachexia are limited, and the molecular mechanism remains poorly understood. Circular RNAs (circRNAs) are a novel family of endogenous noncoding RNAs that have been proposed to regulate gene expression in mammals. Exosomes are small vesicles derived from cells, and recent studies have shown that circRNAs are stable in exosomes. However, little is known about the biological role of circRNAs in exosomes. In our study, we showed that circRNAs in plasma exosomes have specific expression features in gastric cancer (GC), and ciRS‐133 is linked with the browning of white adipose tissue (WAT) in GC patients. Exosomes derived from GC cells deliver ciRS‐133 into preadipocytes, promoting the differentiation of preadipocytes into brown‐like cells by activating PRDM16 and suppressing miR‐133. Moreover, knockdown of ciRS‐133 reduced cancer cachexia in tumor‐implanted mice, decreasing oxygen consumption and heat production. Thus, exosome‐delivered circRNAs are involved in WAT browning and play a key role in cancer‐associated cachexia.
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Although metabolic dysfunction has been proposed as a cause for tumor cachexia, a wasting disorder of adipose and skeletal muscle accompanied by systemic inflammation, the mechanisms remain unclear. Here, the authors reveal the role of exosome‐delivered circRNAs in cancer‐associated cachexia. They identify one exosome‐circRNA secreted by cancer cells that plays a key role in regulating differentiation of preadipocytes by working as a microR‐133 sponge. In both gastric cancer patients and animal models, tumor exosomes promote WAT browning. Furthermore, tumor‐derived circRNA accelerates oxygen consumption and glucose expenditure of brown‐like adipocytes in vitro; and in vivo, exosome‐circRNA aggravates cachexia in tumor‐implanted mice.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Several studies have reported the efficacy of traditional Chinese medicine (TCM) for central serous chorioretinopathy (CSC), while some ophthalmologists are concerned that TCM may be a risk factor ...for CSC as some chinese herbs contain hormonal ingredients. This study aimed to evaluate the efficacy and safety of TCM in treating patients with CSC. Randomized controlled trials (RCTs) and observational studies of TCM for CSC were searched up to July 10, 2023 on the following biological databases without language and publication time restrictions: PubMed, Ovid Medline, Embase, Cochrane Library, The Chinese National Knowledge Infrastructure Database (CNKI), Technology Periodical Database (VIP), Wanfang, and Chinese Biomedical Literature Service System (SinoMed). Review Manager V.5.4.1 and Stata 14 software were used for data analysis. Finally, thirty-eight studies were finally included including 23 RCTs and 15 cohort studies. The meta-analysis showed that compared with the routine treatment alone, the combination of TCM can not only reduce the recurrence rate (OR = 0.29, 95% CI: 0.21,0.40; I.sup.2 = 0%) and central retinal thickness (CRT) (MD = - 35.63, 95% CI: - 45.96,-25.30; I.sup.2 = 89%) of CSC, but improve patients' best corrected visual acuity (BCVA) (SMD = 0.86, 95% CI: 0.62,1.11; I.sup.2 = 77%); additionally, it has no obvious side effects compared with routine treatment (OR = 0.72, 95% CI: 0.39,1.34; I.sup.2 = 10%). Overall, this study shows that the use of TCM does not increase the risk of CSC recurrence; on the contrary, the combination of TCM may reduce the recurrence of CSC and improve BCVA and CRT in patients with CSC compared with conventional treatment.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Owing to their special photoelectric properties, halide perovskites have always attracted research attention. Hollow‐structured halide perovskites have many practical applications but are challenging ...to prepare as most template methods violate their poor chemical and thermal stability. In this study, novel halide perovskite Cs2PdBr6 hollow nanospheres are prepared using a template‐free method; specifically, large quantities of highly pure lead‐free halide perovskite Cs2PdBr6 hollow nanospheres are produced at 30 °C without a surfactant. These ultrapure nanospheres exhibit superiority in chemresistive detection of CO with a detection limit of 50 ppb, which is the lowest among all the reported CO sensing materials. Moreover, in situ sum‐frequency‐generation spectra and density functional theory calculations reveal that the high sensitivity is attributable to the large specific surface area and surfactant‐free surface of rich Br− vacancies that favor CO binding. Overall, this work provides insight on regulation of the halide perovskite structure and the use of hollow spheres in gas‐sensing applications.
Highly pure lead‐free halide perovskite Cs2PdBr6 hollow nanospheres are synthesized in large quantities using a surfactant‐free one‐step method. These ultrapure nanospheres exhibit superiority in detection of CO with a lower limit of 50 ppb, which is the lowest among all reported CO chemresistive materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Polyethylene has excellent electrical insulation, but its low thermal stability and breakdown strength limit its application in the field of high‐voltage (HV) and ultrahigh voltage (UHV) power ...cables. In this work, we have developed a new organic peroxide, 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy) hexane (Bi25), which can efficiently trigger the crosslinking of polyethylene (Bi25‐XLPE). Bi25‐XLPE does not produce gas byproducts and has a longer scorching time. All performance of Bi25‐XLPE sheets fulfill the standard of the 500 kV power cable insulation due to the void‐free nature, higher crosslinking density and crystallinity. In addition, one 500 kV power cable model was constructed by COMSOL, which confirmed the breakdown strength (up to 61.66 kV/mm) and stability of Bi25‐XLPE.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Increasingly frequent and intense heatwaves threaten ecosystem health in a warming climate. However, plant responses to heatwaves are poorly understood. A key uncertainty concerns the intensification ...of transpiration when heatwaves suppress photosynthesis, known as transpiration-photosynthesis decoupling. Field observations of such decoupling are scarce, and the underlying physiological mechanisms remain elusive. Here, we use carbonyl sulphide (COS) as a leaf gas exchange tracer to examine potential mechanisms leading to transpiration-photosynthesis decoupling on a coast live oak in a southern California woodland in spring 2013. We found that heatwaves suppressed both photosynthesis and leaf COS uptake but increased transpiration or sustained it at non-heatwave levels throughout the day. Despite statistically significant decoupling between transpiration and photosynthesis, stomatal sensitivity to environmental factors did not change during heatwaves. Instead, midday photosynthesis during heatwaves was restricted by internal diffusion, as indicated by the lower internal conductance to COS. Thus, increased evaporative demand and nonstomatal limitation to photosynthesis act jointly to decouple transpiration from photosynthesis without altering stomatal sensitivity. Decoupling offered limited potential cooling benefits, questioning its effectiveness for leaf thermoregulation in xeric ecosystems. We suggest that adding COS to leaf and ecosystem flux measurements helps elucidate diverse physiological mechanisms underlying transpiration-photosynthesis decoupling.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this paper, the slit Hopkinson pressure bar (SHPB) experiments were conducted to investigate the dynamic mechanical characteristics of red sandstone during acid dry-wet cycles. The appearance of ...the samples was evaluated using scanning electron microscopy, and the process of red sandstone degradation under acid dry-wet cycles was examined. The results reveal that, as compared to neutral solution, acid solution enhances the degree of degradation induced by dry-wet cycles in red sandstone. The dynamic compressive strength and elastic modulus of red sandstone steadily decline as the number of dry-wet cycles increases, and the lower the pH of solution, the greater the reduction. The mechanism of degradation of red sandstone during acid dry-wet cycles may be explained in two ways. First, the chemical interaction between the mineral components in the sample, such as cement and feldspar, and H+ in the acid solution has accelerated the formation of secondary pores and fractures, resulting in a decrease in the cementation capacity between mineral particles. Second, partial breakdown of the major mineral particles softens the mineral skeleton.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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