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ABSTRACTWe investigated the mechanism of erythropoietin (EPO) in brain injury in premature mice based on Akt/mTOR/p70S6K signaling pathway. The brain injury model group of premature mice was obtained by intraperitoneal injection of lipopolysaccharide during pregnancy. Normal mice were taken as the control group. The model mice were divided into low-dose EPO (1,000 IU/kg, L-EPO), medium-dose EPO (2,500 IU/kg, M-EPO), and high-dose EPO groups (5,000 IU/kg, H-EPO) by intraperitoneal injection. The levels of malondialdehyde (MDA) and total superoxide dismutase (T-SOD) were detected. TUNEL staining and Western blotting were used to detect the differences in neuronal apoptosis index (AI), microglial polarization marker protein, and Akt/mTOR/p70S6K-related protein expression levels in each group. Compared with the control group, the protein levels of AI, MDA, Bax, and iNOS in the model, L-EPO, and M-EPO groups were significantly increased, while the T-SOD level and Bcl-2, ARG1, p-Akt, p-mTOR, and p-70S6K protein levels were significantly decreased (P< 0.05). Compared with the model group, AI, MAD levels and Bax, iNOS protein expression levels in L-EPO, M-EPO, and H-EPO groups were significantly decreased, while T-SOD level and Bcl-2, ARG1, p-Akt, p-mTOR, and p-70S6K protein levels were significantly increased. The changes were dose-dependent. In summary, EPO can activate microglia transformation from M1 to M2 through Akt/mTOR/p70S6K signaling pathway.

Objective:To determine the significance of the nasopharyngeal cavity area (S) in diagnosing and treating adenoid hypertrophy (AH) in children by measuring it with cone beam computed tomography (CBCT). Methods:A retrospective analysis was conducted on the clinical data of eighty-five 5- to 6-year-old children with AH admitted to the Department of Otorhinolaryngology at Dalian Central Hospital between January 2022 and April 2023. Of the 85 patients, 48 were male and 37 were female; all had been diagnosed with AH and underwent surgery. Sleeping with open-mouth breathing was frequently accompanied by clinical manifestations such as chronic sinusitis in most patients. Every patient was subjected to a CBCT examination of the nasopharynx and 3D airway reconstruction. The adenoid thickness (A) and nasopharyngeal cavity width (N) were measured in the sagittal plane, while the S was measured in the coronal plane. The factors that had a significant impact on S’s size was analyzed using linear regression. Results:S and age, A, N, height, weight, BMI, allergic rhinitis, deviated nasal septum, and enlarged turbinate hypertrophy did not differ significantly (P> .05). However, there was a significant linear relationship between A/N and chronic sinusitis (R2= 0.948, P< .01). Regression equation: S = −4.115 × A/N × 100-5.037 × 1/0 (with chronic sinusitis/without chronic sinusitis) +418. 097. The calculated S in individuals with A/N = 70% and no chronic sinusitis was 130 mm2. Conclusion:The S can be used as an important imaging index for diagnosing and evaluating the severity of AH in minors. When a child exhibits clinical signs of AH but A/N ≤ 70%, it is difficult to determine whether surgical intervention is necessary. At this time, CBCT is required to measure the nasopharyngeal cavity’s size. When S ≤ 130 mm2, the patient should actively undertake surgical treatment.

A bioinspired photocatalytic nanocomposite membrane was successfully prepared via polydopamine (pDA)-coated poly(vinylidene fluoride) (PVDF) membrane, as a secondary platform for vacuum-filtrated Au-TiO2nanocomposites, with enhanced photocatalytic activity. The degradation efficiency of Au-TiO2/pDA/PVDF membranes reached 92% when exposed to visible light for 120 min, and the degradation efficiency of Au-TiO2/pDA/PVDF membranes increased by 26% compared to that of Au-TiO2powder and increased by 51% compared to that of TiO2/pDA/PVDF nanocomposite membranes. The degradation efficiency remained about 90% after five cycle experiments, and the Au-TiO2/pDA/PVDF nanocomposite membranes showed good stability, regeneration performance, and easy recycling. The pDA coating not only served as a bioadhesion interface to improve the bonding force between the catalyst and the membrane substrate but also acted as a photosensitizer to broaden the wavelength response range of TiO2, and the structure of Au-TiO2/pDA/PVDF also improves the transfer rate of photogenerated electrons; the surface plasmon resonance effect of Au also played a positive role in improving the activity of the catalyst. Therefore, we believe that this study opens up a new strategy in preparing the bioinspired photocatalytic nanocomposite membrane for potential wastewater purification, catalysis, and as a membrane separation field.

In order to achieve high performance in visible-light photocatalysis, V4+and Ce3+self-doped BiVO4/CeO2heterostructured nanocomposites with high surface areas were prepared using the templating approach employing mesoporous silica MCM-41 as the hard template. X-ray photoelectron spectroscopy (XPS) spectra have demonstrated the presence of plentiful V4+and Ce3+species in the nanocomposites accompanied by the formation of oxygen vacancies. The presence of V4+species is further identified by the electron spin resonance (ESR) spectrum. Furthermore, the BiVO4and CeO2could be affecting each other by arousing the structural changes in the formed nanocomposites. The V4+and Ce3+self-doped 0.4BiVO4/0.6CeO2nanocomposite with the surface area as large as 78.35 m2/g exhibits the highest photocatalytic activity for the rhodamine B (RhB) and methyl orange (MO) degradation and photoelectrochemical performances. The enhanced photocatalytic mechanism is systematically studied via UV–vis diffuse reflectance spectra (DRS), photoluminescence (PL) spectra, transient photocurrent responses, and electrochemical impedance spectroscopy (EIS) spectra. The remarkable enhanced photocatalytic activity could be mainly attributed to the formed heterojunction nanostructures, the presence of defect states induced by oxygen vacancies, and self-doped V4+and Ce3+centers, as well as high surface areas. A possible photocatalytic mechanism over the V4+and Ce3+self-doped BiVO4/CeO2nanocomposites is proposed based on the active species trapping experiments and calculated energy band structures.

Recent experiments and computer simulation studies on nanoconfined ionic liquids (ILs) have shifted the focus from perpendicular to lateral distribution, the understanding of which is crucial for IL performance in the field of energy storage systems and tribology. In this article, the structure of 1-ethyl-3-methylimidazolium bromide, [Emim][Br], confined by a hydroxyl group functionalized surface of kaolinite plates has been studied by molecular dynamics simulation. Depending on the degree of confinement, the IL anion can pack into a two-dimensional (2D) ordered structure with square symmetry, coexisting liquid–solid phase, or liquidlike structure. The ordered structure arises from surface-induced ionic orientational preference and the driving force from confinement that supports the formation of the 2D planar structure. The flexible H-bond formed between Br and surface hydroxyl group at fixed d-spacing results in the liquidlike ordering that breaks down the electrostatic network in ILs. The influence of water addition varies when confining plates are treated differently, namely, forming large H-bonding network and small isolated oligomers for relaxed and fixed d-spacing, respectively. This work reveals additional information about the relative importance of factors like packing constraints, interaction within ILs, and selective attraction in determining the structure and dynamics of confined ILs.

A series of S2O82−/xwt% Ce–Al–Fe–O solid acid catalysts were prepared by the sol–gel method. Their catalytic performances for the synthesis of n-butyl acetate from acetic acid and n-butanol were investigated. The catalytic properties and crystalline phases of S2O82−/xwt% Ce–Al–Fe–O solid acid catalysts were characterized by XRD, IR, TG/DSC and SEM techniques. Experimental results showed that S2O82−/10 wt% Ce–Al–Fe–O solid acid catalyst exhibited the highest catalytic activity with 99.90 % esterification efficiency of acetic acid. Moreover, the S2O82−/10 wt% Ce–Al–Fe–O solid acid catalyst showed excellent stability with no obvious change in catalytic activity even after being used repeatedly for eight times.

Abstract: New types of S2O82−/Al-x wt%Ce–Zn–O solid acid catalysts were prepared by the sol–gel method. Their catalytic performances for the synthesis of n-butyl acetate from acetic acid and n-butanol were investigated. The characterization of prepared catalysts was performed using XRD, IR, TG-DSC and SEM. The experimental results showed that the S2O82−/Al-2.5 wt%Ce–Zn–O solid acid catalyst exhibited an optimal esterification performance with 98.71% esterification efficiency under the optimum synthesis conditions. Moreover, the S2O82−/Al-2.5 wt%Ce–Zn–O solid acid catalyst retained its high activity with above 95% esterification efficiency after being used repeatedly for seven times, which indicated that the S2O82−/Al-2.5 wt%Ce–Zn–O solid acid catalyst had excellent stability.

Abstract: The Sulu (苏鲁)-Dabie (大别) orogen in East-Central China formed during the subduction and collision of the Yangtze block with the North China block in Early Mesozoic (240–225 Ma). Constraints on the nature and derivation of eclogites, which are a significant component of the orogen, can provide useful information about subduction-zone metamorphism and crust-mantle interaction. The U-Pb ages, Hf-isotope ratios and trace-element compositions of zircons in eclogites from the Jiangzhuang (蒋庄) (Jiangsu (江苏) Province) and Rongcheng (荣成) (Shandong (山东) Province) areas indicate that the protoliths of the eclogites derived from ultramafic-mafic complexes or mafic intrusion in the subducted continental lithosphere. The upper intercept age of 852±10 Ma and high ɛ Hf (up to 14.7) of the Neoproterozoic zircons in a Jiangzhuang sample indicate that the protoliths represent products of the Neoproterozoic addition of juvenile materials to the older (i.e., Paleo-Mesoproterozoic) continental crust. The zircon ages of eclogites from both localities mainly record the Triassic (230–220 Ma) metamorphism, consistent with the formation of the Sulu orogen in Early Mesozoic. The lower intercept age of 316±4 Ma in a Jiangzhuang sample suggests that thermal activity relating to the paleo-Tethyan in Late Carboniferous also affected the eclogitic protolith.

Defect microstructures of minerals are a potential indicator of extremely rapid and episodic exhumation of ultrahigh-pressure (UHP) metamorphic rock. The microstructure defects in the minerals from UHP jadeite quartzite at Shuanghe, Dabie Mountains, China, have been investigated using transmission electron microscope (TEM) and Fourier transform infrared spectroscopy (FTIR). TEM observations indicate that three polymorphs, namely, submicron-scale nature monalbite (MA, C2/m) (about 0.8 μm), high albite (HA, CĪ), and low albite (LA, CĪ) occur in jadeite inclusions from jadeite quartzite. The existence of monalbite (MA) implies that high-temperature metamorphism (>930 °C) takes place during exhumation and rapid cooling, during retrogression. The occurrence of nanoscale coesite (about 80 nm) and halite daughter minerals in quartz inclusions provide evidence for the transformation of the original coesite to quartz and the existence of high-salty fluids at peak metamorphic conditions. Structural water (OH/H2O) in nominally anhydrous minerals (NAMs) exists in the structures of these minerals as defects. The FTIR results show that the average contents of structural water in jadeite, garnet, rutile, and quartz are 1000 × 10−6, (900–1600) × 10−6, > 2000 × 10−6, and < 4 × 10−6, respectively, and the estimated whole-rock water content is (490–600) × 10−6. The results reveal that the water in crust or protolith can transport into the earth's depth through NAMs during HP-UHP metamorphism. These unique defect microstructures can be rationalized by a high strain rate at local weakening and deep faulting of continental collision orogens.

We designed a numerical experiment to characterize the impact of a dynamic chlorophyll‐specific absorption coefficient (aph∗) on the retrieved temporal pattern of chlorophyll concentration (Chl) from ocean color (Rrs). It is found that, even for oceanic waters, without consideration of the temporal variation of aph∗, Chlderived from a synthesized annual Rrsusing the “standard” ocean color algorithms will generate false dynamic patterns of Chlor questionable phytoplankton phenology. For instance, for an annual Chlwith spring and fall blooms, the inverted Chlfrom Rrscould show a delay of spring bloom by ∼1–3 weeks, along with a perceived earlier appearance of fall bloom or a false bloom during summer. These results highlight the complex relationships between Rrs(an optical property) and Chl(a biological property) in aquatic environments, in particular, the importance and necessity to characterize and understand the temporal variations of aph∗. The chlorophyll‐specific absorption coefficient (aph∗) serves as a link between phytoplankton absorption coefficient and chlorophyll concentration (Chl). Because ocean color (Rrs) is driven by absorption and backscattering coefficients, a change of either aph∗or Chlcan modify Rrs. Consequently, even for “Case‐1” waters, a change of Rrsmay not necessarily represent a change of Chl, unless aph∗co‐varies with Chl. Measurements at the Hawaii Ocean Time‐series showed that aph∗can be ∼40% higher in summer than in winter, which is ∼3 times of that predicted from the range of Chl. Such a behavior suggests there could be considerable uncertainties in the temporal pattern of Chlderived from ocean color, where such temporal variations are the base to study phytoplankton phenology. We thus used synthesized annual time series of Chland aph∗to evaluate the impact of a dynamic aph∗on the temporal variation of Chlretrieved from Rrsand found that there could be a large difference in the timing of maximum Chlas well as the duration of blooming. The results emphasize the importance to characterize and understand the dynamics of aph∗in order to obtain accurate temporal patterns of Chlfrom satellite ocean color measurements, which is crucial for phytoplankton phenology study. The omission of the temporal variation of aph∗in ocean color inversion could result in false chlorophyll temporal pattern or phytoplankton phenologyIt is important and necessary to characterize the spatial and temporal variation of aph∗for better retrieval of chlorophyll dynamicsaph(440) is a more reliable output than Chlfrom ocean color remote sensing at least for oceanic waters The omission of the temporal variation of aph∗in ocean color inversion could result in false chlorophyll temporal pattern or phytoplankton phenology It is important and necessary to characterize the spatial and temporal variation of aph∗for better retrieval of chlorophyll dynamics aph(440) is a more reliable output than Chlfrom ocean color remote sensing at least for oceanic waters

Our efforts to introduce defects in rutile by conventional mechanical grinding as used for TEM study did not produce any defects or twinning. Experimental SAED patterns of rutile with intercalated α-PbO2-type TiO2lamellae are consistent with those expected from calculated patterns. The values and precision of lattice parameters of α-PbO2-type TiO2derived from such SAED patterns are also consistent with crystal data from X-ray diffraction studies.