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Macrophages consist of a heterogeneous population of functionally distinct cells that participate in many physiological and pathological processes. They exhibit prominent plasticity by changing their different functional phenotypes represented by proinflammatory (M1) and anti-inflammatory (M2) in response to different environmental stimuli. Emerging evidence illustrates the importance of intracellular metabolic pathways in macrophage polarizations and functions. In the tumor microenvironment (TME), macrophages tend to M2 polarization, which promotes tumor growth and leads to adverse physiological effects. Due to the lack of highly specific antigens in M1 and M2 macrophages, significant challenges present in isolating these subtypes from clinical samples or in vitro coculture models of tumor-immune cells. In reverse, the single-cell technique provides the possibility to investigate the factors influencing macrophage polarization in the TME. In this research, we employed inertial microfluidic chip-mass spectrometry (IMC-MS) to conduct single-cell metabolomics analysis of macrophages polarized into the two major phenotypes, respectively, and 213 metabolites were identified in total. Subsequently, differential metabolites between macrophage phenotypes were analyzed using volcano plots and binary logistic regression models. Glutamine was pinpointed as a key metabolite for the M1 and M2 phenotypes. Experimental results from both monoculture and coculture cell models demonstrated that M1 polarization is more reliant on the presence of glutamine in the culture environment than M2 polarization. Glutamine deficiency resulted in failed M1 polarization, while its absence had a less pronounced effect on M2 polarization. Replenishing an appropriate amount of glutamine during the intermediate stages of coculture models significantly enhanced the proportion of M1 polarization and suppressed the growth of tumor cells. This research elucidated glutamine as a key factor influencing macrophage polarization in the TME via single-cell metabolomics based on IMC-MS, offering promising insights and targets for tumor therapies.

The primary drivers of eutrophication in lakes following the reduction of external nutrient inputs are the release of N and P from sediments. Constructed wetlands play a pivotal role in ameliorating N, P, and other biogenic element levels. However, the presence of large vegetation in these wetlands also substantially contributes to nutrient accumulation in sediments, a phenomenon influenced by seasonal variations. In this study, a typical constructed wetland was selected as the research site. The research aimed to analyze the forms of N and P in sediments during both summer and winter. Simultaneously, a comprehensive pollution assessment and analysis were conducted within the study area. The findings indicate that elevated summer temperatures, together with the presence of wetland vegetation, promote the release of N through the nitrification process. Additionally, seasonal variations exert a significant impact on the distribution of P storage. Furthermore, the role of constructed wetlands in the absorption and release of N and P is primarily controlled by the influence of organic matter on nitrate‐nitrogen, nitrite‐nitrogen, and available phosphorus, and is also subject to seasonal fluctuations. In summary, under the comprehensive influence of constructed wetlands, vegetation types, and seasons, sediments within the lake generally exhibit a state of mild or moderate pollution. Therefore, targeted measures should be adopted to optimally adjust vegetation types, and human intervention is necessary, involving timely sediment harvesting during the summer to reduce N and P loads, and enhancing sediment adsorption and retention capacity for N and P during the winter. High temperatures and wetland plants promote nitrification, thereby enhancing the release of N from the sediment.The uptake and release of N and P are controlled by the effects of organic matter (OM) on nitrate‐nitrogen, nitrite‐nitrogen, and available phosphorus.The control of OM by wetlands is subject to seasonal cycles. The primary drivers of eutrophication in constructed wetlands following the reduction of external nutrient inputs are release of N and P from sediments. A constructed wetland was selected to analyze the forms of N and P in sediments during summer and winter, and a pollution assessment was conducted. We find that elevated summer temperatures, together with vegetation, promote release of N through nitrification process. Furthermore, the role of constructed wetlands in absorption and release of N and P is primarily controlled by the influence of organic matter on nitrate‐nitrogen, nitrite‐nitrogen, and available phosphorus, and is also subject to seasonal fluctuations. Under the comprehensive influence of constructed wetlands, vegetation, and seasons, sediments exhibit mild or moderate pollution. Therefore, human intervention is necessary, involving timely sediment harvesting during the summer to reduce N and P loads, and enhancing sediment adsorption and retention capacity for N and P during the winter.

In this study, the Mo0.5NbTiZrTax(x = 0.3, 0.5, 0.7) HEAs obtained by arc melting were controlled by the change of Ta content. The microstructure, the wear properties, and the corrosion resistance of the alloys were studied systematically. The results revealed that the alloys have the BCC (major) phase + BCC (minor) phase structure. At the same time, the increase in Ta content promotes the refinement of grains and the formation of sub-grains with gradually random orientation at grain boundaries but suppresses the randomization of crystal orientation. This also enriched the defect structure inside the alloys, further induced the formation of Zr-rich second phase particles, high-density stacking fault structures, and disordered Zr-rich BCC phases. The increase in Ta content significantly improved the wear properties of the alloys, which is mainly ascribed to the presence of the tough BCC phase and the combined effects of solid solution strengthening, second phase strengthening, fine grain strengthening, lattice distortion effect, and stacking fault strengthening. The electrochemical measurements confirm that the overall corrosion resistance of the alloys shows a trend of first increasing and then decreasing with the increase of Ta content due to the formation of micro batteries between the second phase rich in Zr as the anode and dendrites.

RB transcriptional corepressor 1(RB) deletion is the most important genomic factor associated with the prognosis of castration-resistant prostate cancer (CRPC) patients receiving androgen receptor (AR) signaling inhibitor therapy. Loss of RBcould support prostate cancer cell growth in a hormone-independent manner, but the underlying mechanism by which RB regulates tumor progression extends far beyond the cell cycle pathway. A previous study indicated that RB inactivates AKT signaling but has no effect on mTOR signaling in cancer cells. Here, we found that the S249/T252 site in RB is key to regulating the transcriptional activity of the tumor-promoting factor TRIM24 in CRPC, as identified through FXXXV mapping. The RB/TRIM24 complex functions through DUSP2, which serves as an intermediate bridge, to activate the mTOR pathway and promote prostate cancer progression. Accordingly, we designed RB-linker-proteolysis-targeting chimera (PROTAC) molecules, which decreased TRIM24 protein levels and inactivated the mTOR signaling pathway, thereby inhibiting prostate cancer. Therefore, this study not only elucidates the novel function of RB but also provides a theoretical basis for the development of new drugs for treating prostate cancer.

The thermal protection of rocket engines is a crucial aspect of rocket engine design. In this paper, the gas film/regenerative composite cooling of the liquid oxygen/liquid methane (LOX/LCH4) rocket engine thrust chamber was investigated. A gas film/regenerative composite cooling model was developed based on the Grisson gas film cooling efficiency formula and the one-dimensional regenerative cooling model. The accuracy of the model was validated through experiments conducted on a 6 kg/s level gas film/regenerative composite cooling thrust chamber. Additionally, key parameters related to heat transfer performance were calculated. The results demonstrate that the model is sufficiently accurate to be used as a preliminary design tool. The temperature rise error of the coolant, when compared with the experimental results, was found to be less than 10%. Although the pressure drop error is relatively large, the calculated results still provide valuable guidance for heat transfer analysis. In addition, the performance of composite cooling is observed to be superior to regenerative cooling. Increasing the gas film flow rate results in higher cooling efficiency and a lower gas-side wall temperature. Furthermore, the position at which the gas film is introduced greatly impacts the cooling performance. The optimal introduction position for the gas film is determined when the film is introduced from a single row of holes. This optimal introduction position results in a more uniform wall temperature distribution and reduces the peak temperature. Lastly, it is observed that a double row of holes, when compared to a single row of holes, enhances the cooling effect in the superposition area of the gas film and further lowers the gas-side wall temperature. These results provide a basis for the design of gas film/regenerative composite cooling systems.

The pollution of uranium (U)-containing radioactive wastewater has been long regarded as a serious threat to the ecosystems and the health of human beings. Herein, we report a CdSe/CdTe heterojunction that shows efficient U(VI) removal viable under the simulated/real solar light. Up to 92 % of total U(VI) (C0= 30 mg/L) can be rapidly removed within 5 min without using any sacrificial agent or protective gas, this high removal efficiency remains stable in the presence of various interfering ions. Detailed analyses indicate that multiple interfaces can be constructed in the heterojunction using a facile two-step hydrothermal method. These interfaces can accommodate photocatalysis and yield a built-in electric field to separate the photogenerated electron/hole pairs better. Meanwhile, the ingeniously anchored Te2-in the heterojunction, which concurrently acts as an endogenous hole scavenger and a hydroxyl radical sacrifice, also makes a positive contribution. Benefiting from the above synergy, removal rate of U(VI) can be optimized to as high as 14.4 mmol/(g·h). This work offers a general strategy for the rational design of high-performance photocatalysts, potentially paving the way for cleaner and safer nuclear power use.

The magnetic carbon material was synthesized by a simple solid-phase method, and a modified imprinting layer was formed on the surface of the magnetic carbon material by molecular imprinting and microwave methods, and the final modified imprinted Ag-Poly (o-phenylenediamine) (Ag-POPD) photocatalyst was used to degrade the antibiotic ciprofloxacin. The as prepared photocatalyst is very sensitive to temperature, and the ciprofloxacin degradation rate in ambient environment (25 °C) was 73.25% higher than at 40 °C. The photocatalyst has high selectivity to ciprofloxacin and is convenient to recover due to its magnetic properties. The significant increase in photocatalytic activity is mainly attributed to the synergistic effect between Ag and magnetic carbon materials that can accelerate the spatial separation of charge carriers. Furthermore, details of the photocatalytic degradation mechanism of the photocatalyst composite are discussed. The described method is a new single-step continuous microwave synthesis, which also opens new ways to modify/tune materials.

The recyclable and stable ZnFe2O4small particle decorated one-dimensional perylene diimide (PDI) S-scheme heterojunction (1D PDI/ZnFe2O4) is prepared by the hydrochloric acid-mediated (HCl-mediated) strategy, interestingly, the morphology of the 1D PDI/ZnFe2O4can also be effectively regulated by HCl-mediated process, the existence of HCl can regulate PDI into a uniform rod structure, while the co-existence of HCl and PDI can limit ZnFe2O4to become the uniform small particles. More importantly, based on the 1D rod structure of PDI and the small size effect of ZnFe2O4, carriers can migrate to the surface more easily, which can improve the photocatalytic activity. Meanwhile, due to the appropriate energy level structure, the S-scheme heterojunction structure is formed between PDI and ZnFe2O4, which eliminates meaningless photo-generated charge carriers through recombination and introduces strong redox to further enhance the photodegradation effect, thereby, 1D PDI/ZnFe2O4exhibits excellent photocatalytic ability, under the visible light irradiation, the degradation rate of tetracycline (TC) with 1D PDI/ZnFe2O4(66.67%) is 9.18 times that with PDI (7.26%) and 9.73 times that with ZnFe2O4(6.85%). This work proposes new ideas for the assembly of magnetic organic-inorganic S-scheme heterojunction photocatalysts.

Photodynamic therapy (PDT) has emerged as a promising approach for tumor treatment due to its non-invasiveness and high selectivity. However, the off-target activation of phototoxicity and the limited availability of tumor-specific biomarkers pose challenges for effective PDT. Here, we present the development of a novel ratiometric near-infrared-II (NIR-II) fluorescent organic nanoprobe, BTz-IC@IR1061, which responds specifically to hypochlorite (HClO) within tumors. This nanoprobe allows ratiometric fluorescence imaging to monitor and guide activated tumor PDT. BTz-IC@IR1061 nanoparticles were synthesized by codoping the small molecule dye BTz-IC, which generates reactive oxygen species (ROS), with the commercial dye IR1061. The presence of HClO selectively activates the fluorescence and photodynamic properties of BTz-IC while destroying IR1061, enabling controlled release of ROS for tumor therapy. We demonstrated the high selectivity of the nanoprobe for HClO, as well as its excellent photostability, photoacoustic imaging capability, and photothermal effects. Furthermore, in vivostudies revealed effective tumor targeting and remarkable tumor growth inhibition through tumor-activated PDT. Our findings highlight the potential of BTz-IC@IR1061 as a promising tool for tumor-specific PDT, providing new opportunities for precise and controlled cancer therapy.

In this work, an efficient AgVO3/MoS2composite photocatalyst was successfully synthesized via a hydrothermal method. The photocatalytic activity of the as-prepared photocatalyst was evaluated by using it for assessing the degradation of different organic pollutants under visible-light irradiation. The composite 3%-AgVO3/MoS2catalyst demonstrated a significantly enhanced photocatalytic activity compared to the pure compounds (AgVO3and MoS2). The reason behind the excellent photocatalytic performance was the modification of MoS2by AgVO3to facilitate O2adsorption/activation. In addition, the composite catalyst facilitates the two-electron oxygen reduction reaction whereby H2O2is generated on the surface of MoS2to produce additional reactive oxygen species (ROSs). ESR coupled with the POPHA fluorescence detection method and a free radical capture experiment were used to elucidate the mechanism of formation of the ROSs, including •OH, •O2−and H2O2. Furthermore, the generation of additional ROSs could accelerate electron consumption, leaving behind more holes for the oxidation of organic pollutants. A possible photocatalytic mechanism of the composite is also discussed.

Temperature sensitive photocatalyst of PNIPAM@ZnO/C was successfully prepared by cross-linking polymerization technology and it possesses excellent and switchable photocatalytic activity.

High nitrous oxide (N2O) and nitrite (NO2--N) emission limit the application of the partial nitrification (PN) technology. A novel aerated vertical flow constructed wetland (VFCW) using waste gas from PN process was designed to enhance nitrogen removal and reduce N2O and NO2--N in PN process. Compared with unaerated VFCW, NH4+-N and TN removal efficiencies in aerated VFCW were significantly improved by 118.48% and 78.14%, respectively. Furthermore, the aerated wetland mode can effectively eliminate the problem of high NO2--N and N2O pollution. After VFCW purification, the NO2--N concentration was reduced from 17.07 mg/L to 0.34 mg/L. Meanwhile, the N2O removal rate could reach 88.72%. Microbial analysis showed that the higher microbial community abundance and more fully nitrification and denitrification process were found in aerated VFCW, led to its reduced NO2--N and N2O emission.

The traditional photocatalysts have no selective photocatalysis ability and are difficult to separate and recycle. Herein, the imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (IM-NSH-PM) was prepared via imprinting modification technology and dopamine (DA) tight adhesion method, which possessed high throughput (2548.6Lm-2h-1bar-1), good self-cleaning performance, excellent stability and recovery performance. The cross-linking and polymerization of DA on PVDF membrane surface can form a strong interaction between basement membrane and imprinted modified non-metal S-scheme heterojunction (IM-NSH), which made IM-NSH-PM adhered closely together. Besides, the formed S-scheme heterojunction between PDI and g-C3N4, which weakened the recombination rate of electrons and holes and further improved the photodegradation ability. The photodegradation rate of TC by IM-NSH-PM reached 71.88%. More importantly, under the action of imprinting modification, IM-NSH was endowed with many imprinted cavities consistent with the three-dimensional structure of tetracycline (TC), thereby TC can be preferentially selective adsorbed and degraded, and the selectivity coefficient of IM-NSH-PM to non-imprinted modified non-metal S-scheme heterojunction photocatalytic membrane (NIM-NSH-PM) was 1.88. This work shows a meaningful idea for exploring self-cleaning membranes with good selective photodegradation ability for the target pollutant.

AbstractDifferent kind of metal ion doped CdSe quantum dots (QDs) are synthesized by a simple hydrothermal method. The prepared samples are characterized by powder X-ray diffraction, transmission electron microscopy, UV-vis absorption spectra, and X-ray photoelectron spectra (XPS), while the catalytic activities of photocatalysts are tested by photocatalytic degradation of tetracycline hydrochloride under visible-light irradiation. The results show that the 4 mol% Co-doped CdSe QDs exhibit the best photocatalytic activities under visible-light irradiation. While the solution condition is changed to further evaluate their photocatalytic activities, it can be concluded that the existence of cationic surfactant gives the best result and the degradation efficiency is 85.47%. Moreover, there is almost no loss of photocatalytic activities after four cycles. Experimentally and theoretically, this study shows that the method of metal ions doping will be useful for the improvement of photocatalytic activities and stabilities of CdSe QDs.

Different kind of metal ion doped CdSe quantum dots (QDs) are synthesized by a simple hydrothermal method. The prepared samples are characterized by powder X-ray diffraction, transmission electron microscopy, UV-vis absorption spectra, and X-ray photoelectron spectra (XPS), while the catalytic activities of photocatalysts are tested by photocatalytic degradation of tetracycline hydrochloride under visible-light irradiation. The results show that the 4 mol% Co-doped CdSe QDs exhibit the best photocatalytic activities under visible-light irradiation. While the solution condition is changed to further evaluate their photocatalytic activities, it can be concluded that the existence of cationic surfactant gives the best result and the degradation efficiency is 85.47%. Moreover, there is almost no loss of photocatalytic activities after four cycles. Experimentally and theoretically, this study shows that the method of metal ions doping will be useful for the improvement of photocatalytic activities and stabilities of CdSe QDs.

AbstractThe Cadmium sulfide (CdS) microsphere photocatalysts with the cauliflower-like morphology have been synthesized by hydrothermal method. The as-prepared photocatalysts have been characterized by powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, UV–vis absorption (UV–vis), and the thermo-gravimetric analysis. The UV–vis measurements show that the CdS microsphere prepared with 2 h have a band gap about 2.13 eV, which is smaller than the reported 2.42 eV, thus the as-prepared photocatalysts can be easily photoexcited and exhibit better photocatalytic performance. The photo-degradation experiments have been performed with CdS photocatalysts prepared with various synthesis conditions. Particularly, the CdS microsphere photocatalysts show the highest degradation ratio (72.78%) of Oxytetracycline hydrochloride under the visible light irradiation.

The Cadmium sulfide (CdS) microsphere photocatalysts with the cauliflower-like morphology have been synthesized by hydrothermal method. The as-prepared photocatalysts have been characterized by powder X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, UV–vis absorption (UV–vis), and the thermo-gravimetric analysis. The UV–vis measurements show that the CdS microsphere prepared with 2 h have a band gap about 2.13 eV, which is smaller than the reported 2.42 eV, thus the as-prepared photocatalysts can be easily photoexcited and exhibit better photocatalytic performance. The photo-degradation experiments have been performed with CdS photocatalysts prepared with various synthesis conditions. Particularly, the CdS microsphere photocatalysts show the highest degradation ratio (72.78%) of Oxytetracycline hydrochloride under the visible light irradiation.

AbstractPolypyrrole–TiO2composited photocatalysts have been prepared by sol–gel method. The as-prepared photocatalysts were characterized by scanning electron microscopy, X-ray diffraction, and FT-IR. The results showed that the polypyrrole–TiO2consists of well-defined hollow tubes with the size of inner diameter 0.5–1 μm, and the hollow tubes exhibited non-crystal phase and it was well-formed anatase phase at high temperature treatment. The performances of polypyrrole–TiO2were tested by adsorption and degradation of salicylic acid. The adsorption equilibrium data, at different temperatures, were described by the Langmuir, Freundich, Temkin and Dubinin–Radushkevich isotherm models. The results showed that the Langmuir model was well fit to the equilibrium adsorption data, and the adsorption capacities could reach 32.4 mg g−1. The photocatalytic degradation activity of salicylic acid with polypyrrole–TiO2was investigated under visible light irradiation. It was revealed that the degradation rate of salicylic acid with the polypyrrole–TiO2which synthesized at 5°C without heat treatment could reach 48.6%. And the kinetics of photocatalytic degradation obeyed second-order kinetics.

Polypyrrole–TiO2composited photocatalysts have been prepared by sol–gel method. The as-prepared photocatalysts were characterized by scanning electron microscopy, X-ray diffraction, and FT-IR. The results showed that the polypyrrole–TiO2consists of well-defined hollow tubes with the size of inner diameter 0.5–1 μm, and the hollow tubes exhibited non-crystal phase and it was well-formed anatase phase at high temperature treatment. The performances of polypyrrole–TiO2were tested by adsorption and degradation of salicylic acid. The adsorption equilibrium data, at different temperatures, were described by the Langmuir, Freundich, Temkin and Dubinin–Radushkevich isotherm models. The results showed that the Langmuir model was well fit to the equilibrium adsorption data, and the adsorption capacities could reach 32.4 mg g−1. The photocatalytic degradation activity of salicylic acid with polypyrrole–TiO2was investigated under visible light irradiation. It was revealed that the degradation rate of salicylic acid with the polypyrrole–TiO2which synthesized at 5°C without heat treatment could reach 48.6%. And the kinetics of photocatalytic degradation obeyed second-order kinetics.

AbstractNonmetal-doped TiO2nanoparticles have been prepared by the solvothermal method. The as-prepared photocatalysts have been characterized by X-ray diffraction, UV–vis diffuse reflectance spectra, Scanning electron microscope, Transmission electron microscopy, Specific surface area (BET) and X-ray photoelectron spectroscopy. The results indicate different atom radius and valence of the N, S and B atoms that cause the different doping ways, and it could form different lattice, which led to different surface area and pore volume of as-prepared photocatalysts. It is confirmed that S as S6+incorporate into the crystal lattice of the S–TiO2, which may be the O–S–O–Ti–O linkages in the crystal lattice. It may be N and S as Ti–N–O or Ti–N–O2and S2−in the crystal lattice of the N&S co-doped TiO2, respectively, which may be the S–Ti–N–O linkages in the crystal lattice. Photocatalytic activity was studied by degradation of salicylic acid under visible light. The degradation rate of salicylic acid reached 76.25% with N&S co-doped TiO2photocatalyst in 120 min, which is the highest of all the as-prepared photocatalysts. Furthermore, the experimental data of photocatalytic degradation well followed the Langmuir–Hinshelwood kinetics.

Nonmetal-doped TiO2nanoparticles have been prepared by the solvothermal method. The as-prepared photocatalysts have been characterized by X-ray diffraction, UV–vis diffuse reflectance spectra, Scanning electron microscope, Transmission electron microscopy, Specific surface area (BET) and X-ray photoelectron spectroscopy. The results indicate different atom radius and valence of the N, S and B atoms that cause the different doping ways, and it could form different lattice, which led to different surface area and pore volume of as-prepared photocatalysts. It is confirmed that S as S6+incorporate into the crystal lattice of the S–TiO2, which may be the O–S–O–Ti–O linkages in the crystal lattice. It may be N and S as Ti–N–O or Ti–N–O2and S2−in the crystal lattice of the N&S co-doped TiO2, respectively, which may be the S–Ti–N–O linkages in the crystal lattice. Photocatalytic activity was studied by degradation of salicylic acid under visible light. The degradation rate of salicylic acid reached 76.25% with N&S co-doped TiO2photocatalyst in 120 min, which is the highest of all the as-prepared photocatalysts. Furthermore, the experimental data of photocatalytic degradation well followed the Langmuir–Hinshelwood kinetics.

AbstractCdS/halloysite nanotube (HNT) samples doped with several metal ions (Mn+-CdS/HNTs, where Mn+= Zn2+, Bi3+, Cr3+, and Ni2+) were synthesized using a facile and effective hydrothermal method. The as-prepared photocatalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, X-ray diffraction, UV–vis diffuse reflectance spectra, inductively coupled plasma-atomic emission spectroscope, X-ray photoelectron spectroscopy, and Fourier transform infrared. The photocatalytic activity of the Mn+-CdS/HNTs photocatalyst was evaluated by the degradation of tetracycline under visible-light irradiation. The optimum Mn+-doping amount was investigated in detail. At last, the possible photodegradation mechanism for metal-ion-doping photocatalyst was further discussed.

CdS/halloysite nanotube (HNT) samples doped with several metal ions (Mn+-CdS/HNTs, where Mn+= Zn2+, Bi3+, Cr3+, and Ni2+) were synthesized using a facile and effective hydrothermal method. The as-prepared photocatalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray energy dispersive spectroscopy, X-ray diffraction, UV–vis diffuse reflectance spectra, inductively coupled plasma-atomic emission spectroscope, X-ray photoelectron spectroscopy, and Fourier transform infrared. The photocatalytic activity of the Mn+-CdS/HNTs photocatalyst was evaluated by the degradation of tetracycline under visible-light irradiation. The optimum Mn+-doping amount was investigated in detail. At last, the possible photodegradation mechanism for metal-ion-doping photocatalyst was further discussed.

AbstractTiO2/HNTs were modified by metal ions with the impregnation method. The as-prepared photocatalysts were characterized by transmission electron microscopy, X-ray diffraction, UV–vis diffuse reflectance spectra (UV–vis DRS), and inductively coupled plasma-atomic (optical) emission spectrometry (ICP-AES). The results demonstrated that TiO2/HNTs were successfully synthesized, and anatase TiO2was formed after calcination. Moreover, after modification, the as-prepared TiO2/HNTs still kept crystalline structure. Furthermore, a red-shift was obviously observed fromUV–vis DRS, and the band gap energy was narrowed. ICP-AES proved that compared with TiO2/HNTs, metal ions were existed in metal ion@TiO2/HNTs. The photocatalytic activity was studied by the degradation of antibiotics aqueous solution under the visible light irradiation. The results showed that Fe3+@TiO2/HNTs had the strong ability to degrade tetracycline, and the optimum adding concentration of Fe3+was 0.2 g/L. In addition, the degradation effect of tetracycline was better. The photodegradation rate of 40 mg L−1tetracycline simulated wastewater could reach 76.54%. The binary system was also investigated, which showed that the degradation rate of co-doped TiO2/HNTs was lower than Fe3+@TiO2/HNTs.

TiO2/HNTs were modified by metal ions with the impregnation method. The as-prepared photocatalysts were characterized by transmission electron microscopy, X-ray diffraction, UV–vis diffuse reflectance spectra (UV–vis DRS), and inductively coupled plasma-atomic (optical) emission spectrometry (ICP-AES). The results demonstrated that TiO2/HNTs were successfully synthesized, and anatase TiO2was formed after calcination. Moreover, after modification, the as-prepared TiO2/HNTs still kept crystalline structure. Furthermore, a redshift was obviously observed fromUV–vis DRS, and the band gap energy was narrowed. ICP-AES proved that compared with TiO2/HNTs, metal ions were existed in metal ion@- TiO2/HNTs. The photocatalytic activity was studied by the degradation of antibiotics aqueous solution under the visible light irradiation. The results showed that Fe3+@TiO2/HNTs had the strong ability to degrade tetracycline, and the optimum adding concentration of Fe3+was 0.2 g/L. In addition, the degradation effect of tetracycline was better. The photodegradation rate of 40mgL-1tetracycline simulated wastewater could reach 76.54%. The binary system was also investigated, which showed that the degradation rate of co-doped TiO2/HNTs was lower than Fe3+@TiO2/HNTs.

ABSTRACTPersistent, high-risk human papillomavirus (HPV) infection is the primary cause of cervical cancer. Neutralizing antibodies elicited by L1-only virus-like particles (VLPs) can block HPV infection; however, the lack of high-resolution structures has limited our understanding of the mode of virus infection and the requirement for type specificity at the molecular level. Here, we describe two antibodies, A12A3 and 28F10, that specifically bind to and neutralize HPV58 and HPV59, respectively, through two distinct binding stoichiometries. We show that the epitopes of A12A3 are clustered in the DE loops of two adjacent HPV58 L1 monomers, whereas 28F10 recognizes the HPV59 FG loop of a single monomer. Via structure-based mutagenesis and analysis of antibody binding, we further identified the residues HPV58 D154, S168, and N170 and HPV59 M267, Q270, E273, Y276, K278, and R283, which play critical roles in virus infection. By substituting these strategic epitope residues into other HPV genotypes, we could then redirect the type-specific binding of the antibodies to these genotypes, thus highlighting the importance of these specific residues, HPV58 R161, S168, and N308 and HPV59 Q270, E273, and D281. Overall, our findings provide molecular insights into potential structural determinants of HPV required for infectivity and type specificity.IMPORTANCEHigh-risk human papillomaviruses (HPVs) are considered the major causative pathogens of cancers that affect epithelial mucosa, such as cervical cancer. However, because of the lack of high-resolution structural information on the sites of neutralization, we have yet to determine the precise mode of HPV infection and how different types of HPV cause infection. Our crystal structures in this study have uncovered discrete binding stoichiometries for two different antibodies. We show that one A12A3 Fab binds to the center of one HPV58 pentamer, whereas five 28F10 Fabs bind along the top fringe of one HPV59 pentamer. Furthermore, through targeted epitope analysis, we show that 6 to 7 discontinuous residues of the L1 major capsid protein of HPV are determinants, at least in part, for virus infection and type specificity. This knowledge will help us to unravel the process of HPV infection and can potentially be used to drive the development of therapeutics that target neutralization-sensitive sites.