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Pr3+ doped high density germanate glasses were prepared by the melt-quenching method. The physical and luminescent properties were investigated. The glass containing BaF 2 represented maximum phonon energy of 810 cm−1, and the glass density was greater than 6 g/cm3. The glass exhibited good radiation resistance under 2 h of X-ray irradiation. Intense blue, green emissions and weak red emissions were observed when the glass was excited by X-ray, and the blue fluorescence lifetimes were in the range of 9.15–12.59 μs The results show that Pr3+ doped germanate glass could be a potential scintillating material in the field of X-ray detection for fast events. [ABSTRACT FROM AUTHOR]

Verbal fluency is an important indicator of human verbal ability. Methods to improve fluency is an interesting issue necessitating investigation. To do this, the current study required participants to randomly receive transcranial alternating current stimulation (tACS) at 10 Hz, 40 Hz (control frequency), and sham stimulation over the prefrontal cortex before a phonemic fluency task. It was found that 10-Hz tACS significantly improved phonemic fluency relative to sham stimulation. This result demonstrates the modulatory effect of 10-Hz tACS on language ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Titanium dioxide nanotube/graphene aerogel (TNGA) particle electrode was prepared. • The treatment of TCH wastewater with low electrolyte concentration was studied. • The TCH degradation efficiency was effectively enhanced by 3D electrode system. • Degradation mechanisms and pathways are proposed. • Three-dimensional electrode system shows good and stable removal performance. In this study, the synthesis of titanium dioxide nanotubes/graphene aerogel (TNGA) as a particle electrode and the application in the three-dimensional (3D) electrode for the treatment of low electrolyte concentration wastewater containing tetracycline hydrochloride (TCH) was studied. The effect of reaction parameters (electrode, electrolyte concentration, cell voltage, initial pH, ratio of TNGA mass to solution volume) on the degradation of TCH in an electrochemical system was investigated. At the optimum conditions (cell voltage 18 V, initial pH 6 and TNGA mass to solution volume ratio 2 mg/mL) predicted by the response surface methodology (RSM), a high TCH degradation rate (90.6 %) was obtained after 3 h. TNGA showed relatively high stability in the electrochemical oxidation of organic pollutants (82.3 %) even after fifty continuous cycling experiments. The quenching experiments and electron paramagnetic resonance (EPR) indicated that TNGA can generate singlet oxygen in the 3D electrode system. Two possible degradation pathways for TCH were given based on possible intermediates. This study first showed that TNGA is an excellent electrocatalytic material as a particle electrode in antibiotic elimination. [ABSTRACT FROM AUTHOR]

Background: Preeclampsia (PE) is a condition of high blood pressure that is usually concurrent with proteinuria in pregnancy. PE complicates the management of both maternal and fetal health and contributes to most adverse pregnancy outcomes, but the mechanism underlying the development of PE remains unclear. In this study, we performed a case-control study to compare the gut microbiota of PE (n = 26), abnormal placental growth (APG, n = 25) and healthy pregnant women (n = 28) and analyzed the potential pathogenic role of gut microbiota in PE progression. Results: The clinical pathophysiological state did not affect the bacterial diversity, while the compositions of the gut microbiota were significantly altered in both the PE and APG groups compared with healthy pregnant women. At the phylum level, TM7 was significantly increased in women with APG. Heterogeneity was observed at the genus level, especially in genera with positive LDA scores, suggesting the stage-dependent effect of gut microbiota on the development of PE. The beneficial bacterium Lactobacillus was markedly depleted in the PE and APG groups but was only correlated with blood pressure (BP) and proteinuria levels in the PE group. Two different bacterial taxa belonged to Lactobacillus showed different correlations (OTU255 and OTU784 were significantly related to PE and APG, respectively). Conclusions: Our results indicated that shifts in the gut microbiota might occur from the early stages of the development of PE, which is of possible etiological and therapeutic importance. [ABSTRACT FROM AUTHOR]

• The cavitation effect of ultrasound has a reactivation effect on the surface of PRB filler, which solves clogging and sloughing of PRB. • Ultrasound promotes the production of ·OH, an important oxidant in the degradation of tetracycline. • Iron shavings have lower cost, higher degradation efficiency and degradation durability compared to ZVI powders. • The coupling of ultrasound with iron shavings significantly promoted the degradation of cyclic structure tetracycline. Permeable reaction barriers (PRB) with metal particles as the main filler are susceptible to passivation and sloughing, and have a low removal efficiency for organic pollutants. This study proposes a synergistic approach that uses the cavitation effect of ultrasound and the oxidized substances produced in the process to maintain the activity of the PRB packing and improve the removal efficiency. We established and compared three different PRB systems: iron shavings/ZVI powder-only PRB system, ultrasound-only PRB system, and iron shavings/ZVI powder-based ultrasound-PRB system. We highlight differences between systems and quantify the impact of ultrasound. The results showed that the removal of tetracycline (TC) was 66 %/41 %, 20 % and 90 %/60 % for the three PRB systems, respectively. The cavitation effect of ultrasound caused the TC degradation intermediates attached to the surface of iron filler to be stripped into the solution, thus involving the deeper iron in the degradation process and improving the degradation efficiency. Iron shavings showed lower flocculation as well as higher coupling efficiency compared to ZVI powder. The presence of ultrasound increased the ·OH in the Fe-based PRB system by 136 % in 5 min. This study provides a new method for increasing the efficiency of the PRB system in TC degradation. [ABSTRACT FROM AUTHOR]

Europium doped borosilicate glasses were prepared in CO reducing atmosphere. The glasses were systematically investigated through XPS, photoluminescence (PL), fluorescence decay curves and X-ray excited luminescence (XEL). XPS results show that the glasses contain Eu2+ and Eu3+ at the same time. Under the excitation of 360 nm light, only a broad blue emission with peak around 440 nm due to the 5d→4f transition of Eu2+ is observed, while the emissions from Eu3+ do not appear in the PL spectra. The fluorescence decay curves were monitored at 440 nm, and the measured lifetimes are in the range of 0.17–0.42 μs. The PL results indicate that the PL emission from Eu2+ is significantly intense than the PL emissions from Eu3+. Upon X-ray excitation, two main emissions with peaks at 445 nm and 616 nm corresponding to Eu2+ and Eu3+ are obtained. The XEL results reveal that the XEL emissions from Eu3+ are comparably intense as the XEL emission from Eu2+. The results indicate that europium doped borosilicate glass could be a potential scintillating material in X-ray detection filed. [ABSTRACT FROM AUTHOR]

• Polypyrrole was applied for the first time in soil electrokinetic remediation. • A new EKR system containing PPy and graphite electrode was constructed. • PPy played a positive effect on the distribution of electric field and Cr(VI) removal in the PPy-EKR. • Enhanced electromigration combined with adsorption and reduction is the key Cr(VI) removal mechanism. A new electrokinetic remediation (EKR) system for remediation of hexavalent chromium (Cr(VI))-contaminated soil was explored in this study, which consists of main electrodes and unenergized auxiliary electrodes. Specifically, the graphite and Polypyrrole (PPy) were applied as main and auxiliary electrodes respectively, and the PPy used was chemically incorporated into linen fabric (LF). Five EKR experiments lasting 72 h were carried out in order to explore the Cr(VI) removal mechanism of the new EKR system. In the presence of PPy, the distribution of electric field along the ion migration direction and electric current were all improved and the Cr(VI) concentration around the auxiliary electrode was dropped. The changes of these parameters promoted the removal of Cr(VI) and the maximum removal efficiency of Cr(VI) in soil was 91.7%. It can be concluded that PPy auxiliary electrode coupled with EKR (PPy-EKR) had a positive effect on the removal of Cr(VI), which could not only accelerate the migration of Cr ions by affecting the distribution of electric field, but also contribute to adsorption and reduction of Cr(VI). Consequently, this research paved a road for the future application of main-auxiliary electrodes system for Cr(VI) removal in soil remediation. [ABSTRACT FROM AUTHOR]

• The mechanism was the combined effect of electromigration and the adsorption of PANI. • Electrolytic rate was enhanced with the addition of the PANI auxiliary electrode. • PANI auxiliary electrode's particle acceleration effect was greater than adsorption. • Location of PANI auxiliary electrodes plays a crucial role in its efficacy. In this study, a polyaniline (PANI) composite supported by nonwoven fabric was synthesized and applied as an auxiliary electrode in conventional electrokinetic remediation for the first time to investigate the effectiveness of the multi-electrode system in remediating Cr-contaminated soil. Firstly, PANI was successfully combined with nonwoven fabric and has a good adsorption performance for chromium (VI) in aqueous solution, which is highly dependent on the pH of the solution. Then a series of electrokinetic experiments with four different auxiliary electrode configurations were conducted to evaluate Cr (VI) removal and its migration behavior. The results show that the Cr (VI) removal can be up to 20% higher than that of the conventional electrokinetic remediation with the existence of auxiliary electrode. And the mechanism about it was the combined effect of electromigration and the adsorption of PANI. The role of PANI auxiliary electrode was more than an adsorbent, but also an accelerator for Cr (VI) migration to the anode, which means it can intercept and adsorb the heavy metal ions passed through during strengthening the electrolysis process. The acidic environment of anode is more favorable for PANI auxiliary electrode's adsorption, but the most effective and economical arrangement about it was on the cathode side with less energy consumption of 115 kW·h/g. Because the effect of the particle acceleration of the PANI auxiliary electrode was greater than that of the adsorption. This multi-electrode system should also be applicable for the removal of anionic chemicals from contaminated soils. [ABSTRACT FROM AUTHOR]

Transparent Tb3+ and Yb3+ codoped oxyfluoride glass ceramics containing CaF2 nanocrystals were prepared by melt quenching and subsequent heat treatment. Crystallization kinetics of CaF2 nanocrystals was investigated by differential scanning calorimetric method. The average apparent activation energy Ea of the crystallization was ∼498 kJ/mol. Moreover, the value of the Avrami exponent n was 1.01. These results suggest that the crystallization mechanism of CaF2 is a diffusion controlled growth process of needles and plates of finite long dimensions. X-ray diffraction patterns and transmission electron microscopy image confirmed the CaF2 nanocrystals in the glass ceramic. Ultraviolet (UV) and visible emission spectra of the as-made glass and the glass ceramic with an excitation of a 974 nm laser diode were recorded at room temperature. An intense UV emission at 381 nm was observed in the glass ceramic. The origin of the enhancement of the emission at 381 nm was investigated using spectroscopic technique and Judd-Ofelt analysis. The enhancement of the emission at 381 nm could be attributed to the change of the ligand field of Tb3+ ions due to the incorporation of some Tb3+ and Yb3+ ions into CaF2 nanocrystals in the glass ceramic. [ABSTRACT FROM AUTHOR]

Tb3+‐doped germanate glass ceramics containing CaF2 nanocrystals were prepared by melt quenching method with subsequent heat treatment. Their microstructures were investigated by XRD and TEM techniques. Their optical properties were studied by the transmittance, the photoluminescence, and the X‐ray excited luminescence (XEL). The luminescence intensity in the glass ceramics under 377 nm light and X‐ray excitations is significantly enhanced. The maximum integrated XEL intensity of the glass ceramics is about 50% of that of the commercial Bi4Ge3O12 (BGO) scintillating crystal. The results indicate that Tb3+‐doped germanate glass ceramic could be a promising scintillating material used in X‐ray detection for slow event. [ABSTRACT FROM AUTHOR]

Abstract Objectives To identify second-allele variant in infants with a known single-allele mutation of the SLC26A4 gene and to determine the frequency of their occurrence; and to investigate the clinical audiological characteristics of infants with bi-allelic mutations in SLC26A4. Methods The study subjects were 371 patients with a single-allele SLC26A4 mutation detected by neonatal deafness gene screening (4 genes and 9 pathogenic variants) who were treated at the otology outpatient department of Beijing Tongren Hospital. The exonic and flanking splice site regions of the SLC26A4 gene were sequenced for all patients. All patients with bi-allelic SLC26A4 mutations underwent audiological evaluation, and some also underwent temporal bone computed tomography and/or inner ear magnetic resonance imaging. Results Of the 371 patients, 314 (84.64%) had an c.919-2A > G heterozygous mutation and 57 (15.36%) had a c.2168A > G (p.H723R) heterozygous mutation. 13 patients (3.50%) had a second-allele variant, including 11 (2.96%) with pathogenic mutations and 1 (0.27%) with a likely benign variant. Of the 13 patients with bi-allelic mutations, 11 had hearing loss and 2 had normal hearing, the latter of whom had c.919-2A > G/c.1766A > G and c.919-2A > G/c.757A > G compound heterozygous mutations, respectively. Four of the 13 patients with bi-allelic mutations had passed the universal newborn hearing screening, including 2 cases (15.38%) with hearing loss. The most prevalent degree of hearing loss was profound (40.91%), followed by severe (36.36%). The most prevalent audiometric configuration was sloping hearing loss (50.00%), followed by flat-type hearing loss (40.91%). Conclusions This is the first report in China of the frequency of occurrence of second-allele variant in infants with a known single-allele mutation of the SLC26A4 gene; the frequency was 3.50% for any type of variant and 2.96% for pathogenic mutations. A novel variant, c.1766A > G (p.Q589R), which is likely benign, was identified. The pathogenicity of c.757A > G (p.I253V) mutation deserves more in-depth research. For infants with bi-allelic SLC26A4 mutations, the degree of hearing loss was mainly severe-to-profound and the audiometric configuration was mainly sloping. [ABSTRACT FROM AUTHOR]

Abstract Eu3+ doped tellurite scintillating glasses were prepared by the conventional melt-quenching method. The physical and luminescent properties of glasses were investigated by DTA, density, transmittance spectra, photoluminescence spectra, and X-ray excited luminescence (XEL) spectra. The densities of the glasses are in the range from 5.89 g/cm3 to 6.05 g/cm3. The glasses exhibit intense red emissions upon 393 nm light and X-ray excitations. The maximum integral XEL intensity of the glasses is about 6% of that of commercial Bi 4 Ge 3 O 12 (BGO) scintillating crystal. The results reveal that Eu3+ doped tellurite glass could be a scintillator candidate used in X-ray detection field. [ABSTRACT FROM AUTHOR]

Abstract Tetracycline (TC), an antibiotic, is persistent in nature and frequently detected in water and sediments. Visible-light-driven photocatalyst for TC degradation is a promising environmental-friendly technology. Bi 2 Zr 2 O 7 , an effective photocatalyst, but no studies on its photodegradation of TC could be found in literature. In this study, Bi 2 Zr 2 O 7 was synthesized by three soft templated sol-gel methods. Three synthesized Bi 2 Zr 2 O 7 catalysts have different structures, morphologies and band gaps. The Bi 2 Zr 2 O 7 nanoparticles synthesized with citric acid as the template (BZO-3) had a larger specific surface area (30.7 m2/g) and a narrower band gap (2.39 eV), and exhibited a better performance for TC degradation under visible light with an efficiency of up to 81.3%. They also exhibited good stability and reusability in recycled experiments. A reaction mechanism of TC degradation by these photocatalyst was proposed. The enhanced photocatalytic performance was mainly due to photogenerated holes of reactive species and TC was mainly degraded on the surface of the photocatalyst. Pathways of TC photodegradation were derived from the result of analyses of the reaction intermediates. In conclusion, Bi 2 Zr 2 O 7 nanoparticles were found effective as photocatalyst for TC photodegradation by visible light. Graphical abstract Image 1 Highlights • Bi 2 Zr 2 O 7 was successfully prepared by three soft-templated sol-gel methods. • The Bi 2 Zr 2 O 7 synthesized using citric acid exhibited effective photodegradation of tetracycline under visible light. • The Bi 2 Zr 2 O 7 showed stable performance in the recycled experiments. • Holes (h+) were mainly responsible for the photodegradation process. • Pathways and mechanism of TC photodegradation were proposed. [ABSTRACT FROM AUTHOR]

Er3+ doped high density germanate glasses with compositions of 50GeO 2 -10BaO–10Al 2 O 3 -15Lu 2 O 3 -(15-x) La 2 O 3 -xEr 2 O 3 (x = 0, 0.1, 0.5, 1.0, 1.5, and 2.0, in mol%) have been prepared by the melt-quenching method. The optical and physical properties of the samples were characterized by differential scanning calorimetry (DSC), density, transmittance spectra, photoluminescence (PL) spectra, and X-ray excited luminescence (XEL) spectra. The densities were in the range from 5.90 to 6.07 g/cm3. The strong green emissions around 552 nm of Er3+ were observed upon the excitations of 378 nm light and the X-ray, and the lifetimes of 552 nm emission were in the range of 20.88–96.47 μs. The results show that Er3+ doped high density germanate glasses could be used as potential scintillators for X-ray CT. [ABSTRACT FROM AUTHOR]

Residential indoor exposure to volatile organic compounds (VOCs) is a major public health concern. However, the relevant pollution sources have not been well characterized in China. In this study, the 24-h integrated concentrations of 55 VOC species in 27 urban residences, Beijing were measured in the summer. The sources were characterized with positive matrix factorization (PMF) and general linear model (GLM). The most abundant species in terms of geometric mean concentration were formaldehyde (55.1 μg/m 3 ), acetaldehyde (18.7 μg/m 3 ), acetone (14.8 μg/m 3 ), toluene (14.1 μg/m 3 ), hexanal (13.8 μg/m 3 ), n -hexadecane (8.9 μg/m 3 ) and n -pentadecane (8.5 μg/m 3 ). PMF generated 7 factors associated with VOC sources, including aldehydes from ozone-initiated secondary reactions, butyraldehyde from hydrolysis of building materials and furniture, wood flooring emission, wooden furniture emission, wall coverings emission, mobile emission and halogenated hydrocarbons of miscellaneous outdoor origin. GLM identified leather sofa as another source of indoor terpenes and formaldehyde. GLM also found composite wood flooring had stronger emission of VOCs than solid wood flooring, except 1,4-dichlorobenzene. A comparison with multiple studies across the world suggested that: (1) more intensive ozone-initiated secondary reactions resulted in the significantly higher indoor carbonyl concentrations in Beijing than in Japan and USA in the summer; (2) the indoor concentrations of benzene and C 12 -C 17 alkanes were much higher in Beijing, due to the traffic conditions and prevalent use of wood flooring varnishing. [ABSTRACT FROM AUTHOR]

Effect of manganese dioxide (MnO 2 ) on tetracycline (TC) removal/degradation in zero-valent iron (ZVI) based permeable reactive barrier (PRB) system was investigated. To analyze the role of MnO 2 , three different PRB columns packed with ZVI, ZVI and a layer of MnO 2 , and MnO 2 were set up to investigate the removal effect and reaction mechanism of ZVI coupling with MnO 2 on TC removal, respectively. The results show that the removal efficiencies of three PRB columns are 65%, 85%, and 50%, respectively. MnO 2 could accelerate the transformation of Fe 2+ into Fe 3+ and combine with Fe 3+ to degrade TC in different reaction sites in the ZVI-MnO 2 PRB system. Hydroxyl radicals (·OH) were produced in this process, which contributed to about 58.3% for the TC degradation. The UV–Vis spectrum demonstrated that A ring of TC was the main reaction site for interaction with Fe 3+ and the BCD rings were crucial for interactions with MnO 2 . On the basis of intermediates identified by LC-ESI-MS, the ring structure of TC was opened, and low-molecular-weight compounds were produced in ZVI-MnO 2 PRB system. [ABSTRACT FROM AUTHOR]

The effects of downflow sludge circulation on granulation and methane recovery at low load were investigated for domestic wastewater treatment in a modified anaerobic reactor. Compared with conventional upflow anaerobic reactors, enhanced granulation with shortened start-up time was achieved and stable granules were successfully cultivated only after 58 days operations. The introduction of downflow sludge circulation resulted in reverse wastewater-sludge flow and uniform sludge distribution in the reaction zone, which contributed to enhanced wastewater-sludge mass transfer and satisfactory performance with a high soluble chemical oxygen demand (SCOD) removal efficiency of 94.8% at hydraulic retention time (HRT) 6 h. Besides, enhanced liquid-to-gas mass transfer caused a lower dissolved CH 4 saturation index of 1.11 and a higher CH 4 recovery efficiency of 79.48% at HRT 6 h. High throughput sequencing revealed a distinct shift of microbial community during start-up period from Proteobacteria to Bacteroidetes and Chloroflexi in the existence of downflow sludge circulation. [ABSTRACT FROM AUTHOR]

As an efficient image contrast enhancement (CE) tool, adaptive gamma correction (AGC) was previously proposed by relating gamma parameter with cumulative distribution function (CDF) of the pixel gray levels within an image. ACG deals well with most dimmed images, but fails for globally bright images and the dimmed images with local bright regions. However, such two categories of brightness-distorted images are universal in real scenarios, such as those incurred by improper exposure and white objects. In order to attenuate such deficiencies, in this paper we propose an improved AGC technique. The novel strategy of negative images is used to realize CE of the bright images, and the gamma correction modulated by truncated CDF is employed to enhance the dimmed ones. As such, local over-enhancement and structure distortion can be alleviated effectively. Extensive qualitative and quantitative experimental results show that our proposed method yields consistently good CE results. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) infiltrated in groundwater has caused potential threats to the safety of drinking water due to its persistence and high toxicity. In this study, three permeable reactive barrier (PRB) columns packed with zero-valent iron( Fe ), zero-valent iron and microorganism( M + Fe ), microorganism( M ) were employed to investigate the removal effect and reaction mechanism of zero-valent iron coupling with microorganisms on TC removal respectively. The results show that the removal efficiencies of three PRB are about 50%, 40% and 10% respectively. Especially, the effect of coupling ZVI and microbe on the degradation of TC is not a simple superposition. ZVI partially or fully degraded TC by adsorption and reduction. ZVI was converted into Fe 2+ and Fe 3+ while TC was degraded. With the presence of Fe 2+ and Fe 3+ , EPS increased obviously and microbial community structure changed distinctly. It is very interesting that Comamonadaceae , Oxalobacteraceae and Chromatiaceae increased obviously in contrast to no ferric situation, and microbic removal efficiency of TC increased at the same time. [ABSTRACT FROM AUTHOR]

Threat generalisation is an adaptive process that is essential for individual survival. In contrast, over‐generalisation is a pathological process that underlies the development of anxiety disorders. Intolerance of uncertainty (IU) is an individual characteristic known to influence threat generalisation by altering the responses to threat in uncertain situations. However, how it affects contextual threat generalisation remains unclear. Here, we used a novel paradigm to investigate whether contextual threat generalisation varied between individuals depending on their IU level (high or low) and the predictability of a situation (predictable or unpredictable). We analysed shock expectancy in 82 participants (age: 18–27 years) during threat acquisition and generalisation. Results showed that compared with the low IU group, the high IU group exhibited increased contextual threat generalisation to threat‐related cues in unpredictable situation. These findings suggest that IU could be a marker for anxiety disorder susceptibility, as well as a target for anxiety treatment. [ABSTRACT FROM AUTHOR]

Eu 3+ doped heavy germanate scintillating glasses were prepared by melt quenching method. Their physical and luminescent properties were investigated. The glasses exhibit the densities of more than 6.5 g/cm 3 . The transmittance spectra show the glasses have good transmittance in the visible region. The glasses show intense red emissions under 393 nm light excitation and X-ray excitation. The lifetimes of 614 nm emission of Eu 3+ -doped germanate glasses are in the range from 1.424 ms to 1.484 ms. The results indicate that Eu 3+ -doped high density germanate scintillating glasses could be of good anti-radiation properties and could be an X-ray scintillating material suitable to X-ray detection for slow event. [ABSTRACT FROM AUTHOR]

Objective: Ambient fine particulate matter (PM2.5) pollution is currently a major public health concern in Chinese urban areas. However, PM2.5 exposure primarily occurs indoors. Given such, we conducted this study to characterize the indoor-outdoor relationship of PM2.5 mass concentrations for urban residences in Beijing. Methods: In this study, 24-h real-time indoor and ambient PM2.5 mass concentrations were concurrently collected for 41 urban residences in the non-heating season. The diurnal variation of pollutant concentrations was characterized. Pearson correlation analysis was used to examine the correlation between indoor and ambient PM2.5 mass concentrations. Regression analysis with ordinary least square was employed to characterize the influences of a variety of factors on PM2.5 mass concentration. Results: Hourly ambient PM2.5 mass concentrations were 3–280 μg/m3 with a median of 58 μg/m3, and hourly indoor counterpart were 4–193 μg/m3 with a median of 34 μg/m3. The median indoor/ambient ratio of PM2.5 mass concentration was 0.62. The diurnal variation of residential indoor and ambient PM2.5 mass concentrations tracked with each other well. Strong correlation was found between indoor and ambient PM2.5 mass concentrations on the community basis (coefficients: r≥0.90, p<0.0001), and the ambient data explained ≥84% variance of the indoor data. Regression analysis suggested that the variables, such as traffic conditions, indoor smoking activities, indoor cleaning activities, indoor plants and number of occupants, had significant influences on the indoor PM2.5 mass concentrations. Conclusions: PM2.5 of ambient origin made dominant contribution to residential indoor PM2.5 exposure in the non-heating season under the high ambient fine particle pollution condition. Nonetheless, the large inter-residence variability of infiltration factor of ambient PM2.5 raised the concern of exposure misclassification when using ambient PM2.5 mass concentrations as exposure surrogates. PM2.5 of indoor origin still had minor influence on indoor PM2.5 mass concentrations, particularly at 11:00–13:00 and 22:00–0:00. The predictive models suggested that particles from traffic emission, secondary aerosols, particles from indoor smoking, resuspended particles due to indoor cleaning and particles related to indoor plants contributed to indoor PM2.5 mass concentrations in this study. Real-time ventilation measurements and improvement of questionnaire design to involve more variables subject to built environment were recommended to enhance the performance of the predictive models. [ABSTRACT FROM AUTHOR]

Transparent Tb 3+ -doped glass ceramics containing BaF 2 nanocrystals were prepared by melt-quenching method with subsequent heat treatment. The XRD and EDS results showed the precipitated crystalline phase in the glass matrix was BaF 2 . Under 376 nm light, Tb 3+ doped oxyfluoride glass ceramics containing BaF 2 nanocrystals showed more intense green emission than the as-made glass, and the emission intensity increased with increasing heat treatment temperature and time. The lifetimes of 541 nm emission of Tb 3+ doped oxyfluoride glass ceramics were longer than that of as-made glass, which are in the range from 3.00 ms to 3.55 ms. Under X-ray excitation, the green emission was enhanced in the glass ceramics compared to the as-made glass. The results indicate Tb 3+ doped oxyfluoride glass ceramics containing BaF 2 nanocrystals could be a material candidate for X-ray glass scintillator for slow event detection. [ABSTRACT FROM AUTHOR]

Measurement of carcinogenic Cr(VI) in ambient PM is challenging due to potential errors associated with conversion between Cr(VI) (a carcinogen) and Cr(III) (an essential nutrient). Cr(III) conversion is a particular concern due to its >80% atomic abundance in total Cr. U.S. Environmental Protection Agency (EPA) method 6800 that uses water-soluble isotope spikes can be used to correct the interconversion. However, whether the enriched Cr(III) isotope spikes can adequately mimic the Cr(III) species originally in ambient PM is unknown. This study examined the water solubility of Cr(III) in ambient PM and discussed its influence on Cr(VI) measurement. Ambient PM10samples were collected on Teflon filters at four sites in New Jersey that may have different Cr emission sources. The samples were ultrasonically extracted with 5 mL DI-H2O (pH 5.7) at room temperature for 40 min, and then analyzed by ion chromatography–inductively coupled plasma mass spectrometry (IC-ICPMS). Cr(III) was below detection limit (0.06 ng/m3) for all samples, suggesting water-soluble Cr(III) species, such as CrCl3, Cr(NO3)3, and amorphous Cr(OH)3, in the ambient PM were negligible. Therefore, the enriched50Cr(III) isotope spike (in the form of Cr(NO3)3) could not mimic the original ambient Cr(III). Only the conversion of53Cr(VI) (in the form of K2CrO4) was taken into account when correcting the interconversion. We then used NaHCO3-pretreated MCE filters (prespiked with enriched isotope species) to measure Cr(VI) in the ambient PM10. The samples were ultrasonically extracted at 60 C pH 9 solutions for 40 min followed by IC-ICPMS analysis. Due to the correction of Cr(VI) reduction, the Cr(VI) concentrations determined by EPA method 6800, 0.26 ± 0.16 (summer) and 0.16 ± 0.11(winter) ng/m3(n = 64), were significantly greater than those by the external standard curve, 0.21 ± 0.17 (summer) and 0.10 ± 0.07 (winter) ng/m3(n = 56) (p < 0.01, Student’s t-test). Our study revealed that appropriate application of EPA method 6800 is important because it only applies to soluble fraction of Cr species in ambient PM.ImplicationsAccurate measurement of carcinogenic Cr(VI) in ambient PM is challenging due to conversion between Cr(VI) (a human carcinogen) and Cr(III) (a human essential nutrient). The conversion of Cr(III) is of particular concern due to its dominant presence in total Cr (>80%). This study examined the water solubility of Cr(III) in ambient PM that was collected at four locations in New Jersey. Then we discussed the influence of Cr(III) solubility on the application of EPA method 6800, which utilizes enriched isotope spikes to correct the interconversion. Our results suggested that appropriate application of EPA method 6800 is important because it only applies to soluble fraction of Cr species. [ABSTRACT FROM AUTHOR]

Highlights: [•] ACFF was selected as the support material of NZVI. [•] Cr(VI) and total Cr removal on ACFF–NZVI was much higher than that on ACFF and NZVI. [•] Most toxic Cr(VI) was transformed to nontoxic Cr(III) by the reduction of ACFF–NZVI. [•] XPS and FTIR analysis were used to investigate the Cr(VI) removal mechanisms. [Copyright &y& Elsevier]

Objective: To assess health risks associated with inhalation exposure to formaldehyde and benzene mainly emitted from building and decoration materials in newly remodeled indoor spaces in Beijing. Methods: We tested the formaldehyde and benzene concentrations in indoor air of 410 dwellings and 451 offices remodeled within the past year, in which the occupants had health concerns about indoor air quality. To assess non-carcinogenic health risks, we compared the data to the health guidelines in China and USA, respectively. To assess carcinogenic health risks, we first modeled indoor personal exposure to formaldehyde and benzene using the concentration data, and then estimated the associated cancer risks by multiplying the indoor personal exposure by the Inhalation Unit Risk values (IURs) provided by the U.S. EPA Integrated Risk Information System (U.S. EPA IRIS) and the California Office of Environmental Health Hazard Assessment (OEHHA), respectively. Results: (1) The indoor formaldehyde concentrations of 85% dwellings and 67% offices were above the acute Reference Exposure Level (REL) recommended by the OEHHA and the concentrations of all tested buildings were above the chronic REL recommended by the OEHHA; (2) The indoor benzene concentrations of 12% dwellings and 32% offices exceeded the reference concentration (RfC) recommended by the U.S. EPA IRIS; (3) The median cancer risks from indoor exposure to formaldehyde and benzene were 1,150 and 106 per million (based on U.S. EPA IRIS IURs), 531 and 394 per million (based on OEHHA IURs). Conclusions: In the tested buildings, formaldehyde exposure may pose acute and chronic non-carcinogenic health risks to the occupants, whereas benzene exposure may pose chronic non-carcinogenic risks to the occupants. Exposure to both compounds is associated with significant carcinogenic risks. Improvement in ventilation, establishment of volatile organic compounds (VOCs) emission labeling systems for decorating and refurbishing materials are recommended to reduce indoor VOCs exposure. [ABSTRACT FROM AUTHOR]

Exposure to phthalates poses adverse health impacts to human beings. In this study, we analyzed 7 phthalates in dust samples, which were collected with vacuum cleaner from 40 to 31 residences in Beijing in summer and winter, respectively. The major phthalates (median concentration in the summer and winter, respectively) were D i BP (55 and 40 ng/mg), D n BP (99 and 30 ng/mg) and DEHP (795 and 335 ng/mg). The concentrations were significantly influenced by season and residence time of house dust. The concentrations of phthalates in dust on plastic surfaces were highest, followed by those on wooden and fabric surfaces. The dust-air partition coefficients (K d) were calculated: the median values were 0.13, 0.02 and 5.62 m3/mg in the summer and 0.06, 0.018 and 0.76 m3/mg in the winter for D i BP, D n BP and DEHP, respectively. A comparison with K d * at equilibrium state suggested that partition between air and dust deviated from equilibrium state in both seasons. The results also revealed that dust-phthalates in the summer may completely originate from source materials via direct transfer and external physical process; while dust-phthalates in the winter may come from both air (via partition) and source material (via direct transfer and external physical process). The influence of temperature on dust-phthalate concentrations differed by season, owing to different origin of dust-phthalates in two seasons. Polar organic components in dust, which are products of reactions between O 3 and unsaturated hydrocarbons in dust, likely played an important role in fate and transport of phthalates. The presence of them resulted in the significant associations between dust-phthalate concentrations and air humidity in the summer. Moreover, the impacts of indoor PM 2.5 concentrations, traffic conditions surrounding residence, household lifestyle and number of occupants were also observed. The mechanisms behind those observations were discussed. [Display omitted] • Dust-air partition of phthalates deviated from equilibrium state. • Product-to-dust phthalates migration included direct transfer and external process. • Origin of dust-phthalates may differ by season. • Built environmental determinants on dust-phthalate concentrations were characterized. [ABSTRACT FROM AUTHOR]

• Presents a combined approach of lifting path planning and assembly sequencing. • Introduces a new BIM-based intelligent assembly scheduler for precast construction. • The scheduler generates the optimal micro-schedule from inbuilt data in BIM. • Proposes a multi-level elitist genetic algorithm to compute the optimal sequence. • A case study is conducted on a real-world 4D BIM model using a tower crane. This research addresses the problem of assembly scheduling in crane-assisted precast construction while considering issues of building layout interference and optimal crane lifting. Traditionally, assembly scheduling and lifting path planning are treated as two separate issues due to their distinct natures. The current work introduces an approach that combines them for precast construction planning to achieve a comprehensive and cost-effective solution. A BIM4D-based Intelligent Assembly Scheduler (BIAS) is designed in conjunction with the Computer-Aided Lifting Planner developed at Nanyang Technological University, Singapore. BIM4D is the Building Information Modeling (BIM) with the time dimension (i.e., scheduling information). Our scheduler takes an inbuilt timeframe for selected precast elements from BIM4D as input and outputs the micro-schedule in terms of the assembly sequence for these precast elements. This problem is solved using multi-objective optimization. Given a group of precast elements and their BIM4D timeframe, the micro-scheduling is determined based on (1) the relative importance of the elements' physical properties, (2) the interference (neighbouring relation) among the elements' positions, and (3) collision-free lifting paths of the elements. A Multi-level Elitist Genetic Algorithm (MEGA) is proposed to determine the optimal sequence taking into consideration of both assembling and lifting for the elements. A case study is performed with the BIM4D data of a residential building. The results of the case study demonstrate BIAS's efficiency and effectiveness for BIM4D based construction scheduling. [ABSTRACT FROM AUTHOR]

In this research, activated carbon fiber heated by microwave (WACF) under nitrogen (N2) atmosphere adsorption of tetracycline antibiotics (TCs) was analyzed. WACF was obtained under the microwave radiation temperature of 600°C and the radiation time of 15 min. The properties of WACF were characterized by a scanning electron microscope (SEM), N2adsorption/desorption isotherms, and X-ray diffraction (XRD) compared with activated carbon fibers (ACF) without any treatment. WACF had lower surface area (1008 m2/g) but higher external surface area (429 m2/g) than ACF (surface area: 1153 m2/g; external surface area: 308 m2/g). Meanwhile, the adsorption efficiencies of TCs (including tetracycline hydrochloride (TC) and oxytetracycline hydrochloride (OTC)) on WACF were both increased by about 4 times. These results indicated that mesoporosity amplification of WACF played a crucial role in the adsorption capacity of the two TCs. The kinetics and equilibrium data were agreed well with the pseudo-second-order kinetics model (R2 > 0.99) and Langmuir isotherm model (R2 > 0.98), respectively. It suggested that the adsorption process was dominated by chemisorption. Batch experiments showed the maximum adsorption capacities for both adsorbates were 339 and 331 mg/g respectively at pH 2. [ABSTRACT FROM AUTHOR]

Abstract: A series of phosphors with nominal compositions of Sr1.7M0.3SiO4−x F x :0.01Eu2+, 0.08Mn2+ (x=0, 0.01, 0.05, 0.1, 0.2) were synthesized through solid-state reaction technique. Their luminescent properties were studied. Three emission bands with peaks at 455, 550 and 670nm are observed in the phosphors under 380nm light excitation. When doped with fluorine, the crystal phases of the phosphors were changed slightly, while the luminescent intensities were remarkably enhanced and colorimetric parameters (chromaticity coordinates, color rendering index and color temperature) were improved. The colorimetric parameters and thermal quenching properties of Sr1.7Mg0.3SiO4−x F x :0.01Eu2+, 0.08Mn2+ phosphors with the comparison with those of commercial 467nm stimulated YAG:Ce3+ phosphors were systematically investigated. These results indicate that the phosphor with optimized composition could be a promising phosphor as a white light-emitting phosphor for near-ultraviolet light-emitting diodes. [Copyright &y& Elsevier]

Abstract: Anaerobic treatment coupled with micro-electrolysis (ATCM) was applied in treatment of anthraquinone dye wastewater. ATCM performed better in the aspect of the removal efficiencies of chemical oxygen demand (COD) and decolorization than single anaerobic treatment (SAT) did. It was observed that the function of iron was inhibited severely with the reason of mostly coverage of sludge as the experiment was carried out gradually. In order to eliminate the impact of the coverage, electrochemical improvement (external electric field) was studied in the paper. According to the results, the color and COD removal efficiencies were 11% and 32% respectively in SAT, while 65% and 56% respectively in ATCM, and finally 90% and 73% respectively in ATCM improved by external electric field. The removal efficiencies dropped as the Na2SO4 concentration was increased and the pH value reached the maximum value of 9. In the system of ATCM, anaerobic sludge bed contributed more to decolorization than iron bed did, while iron bed played a more important role in ATCM improved by external electric field (ATCM-E). [Copyright &y& Elsevier]

To evaluate the feasibility of using an intrarectal Foley catheter during ultrasound-guided high-intensity focused ultrasound (US-HIFU) in patients with benign uterine diseases of the posterior wall beyond the HIFU therapeutic range. Patients were treated with US-HIFU and lesion changes were monitored using contrast-enhanced MRI from June 2020 to September 2021. A Foley catheter was inserted into the rectum to facilitate a successful US-HIFU ablation. Complications and lesion responses were recorded during the treatment and follow-up. Thirteen patients with 14 lesions beyond the device's treatable area were enrolled. The average placement time and insertion depth of the intrarectal Foley catheter was 7.6 ± 2.7 min and 23.2 ± 7.6 cm, respectively. A median of 50 mL degassed water was injected into the Foley catheter balloon. All 14 lesions were successfully pushed into a treatable area and subjected to HIFU. The average treatment time, irradiation time, and total therapeutic energy of HIFU were 44.2 ± 17.3 min, 394.4 ± 295.7 s, and 73.3 ± 46.6 kJ, respectively. The mean non-perfusion volume (NPV) in all treated lesions was 23.2 ± 19.2 cm3, and the mean NPV ratio was 57.8 ± 16.9%. Major complications were not observed. Intrarectal Foley catheter-assisted US-HIFU is effective and safe. Its clinical application could benefit patients with benign uterine diseases outside the HIFU therapeutic range. [ABSTRACT FROM AUTHOR]

Abstract: Eu2+, Mn2+ doped Sr1.7Mg0.3SiO4 phosphors were prepared by high temperature solid-state reaction method. Their luminescence properties were studied. The emission spectra of Eu2+ singly doped Sr1.7Mg0.3SiO4 consist of a blue band (455nm) and a green band (550nm). The relative intensities of two emissions varied with Eu2+ concentration. Eu2+ and Mn2+ co-doped Sr1.7Mg0.3SiO4 phosphors emit three color lights and present whitish color. The blue (455nm) and green (550nm) emissions are attributed to the transitions of Eu2+, while the red (670nm) emission is originated from the transition of Mn2+ ion. The results indicate the energy transfer from Eu2+ to Mn2+. The mechanism of the energy transfer is resonance-type energy transfer due to the spectral overlap between the emission of Eu2+and the absorption of Mn2+. [Copyright &y& Elsevier]

Abstract: Eu3+-doped Sr2Si1−x Ge x O4 (x=0–1) phosphors have been prepared by the high temperature solid-state reaction method. The luminescent properties of these phosphors were investigated. Red fluorescence of Eu3+ is enhanced gradually in the samples with increasing substitution of Si by Ge upon the excitation of 393nm light. The intensity is increased by 50% with full substitution of Si by Ge. These results are originated from the structural changes and the phonon energy reduction in the samples due to the substitution of Si by Ge. The CIE chromaticity coordinates of the phosphors vary slightly around (0.62, 0.37) and all are in the red color region. The results indicate that these phosphors could be promising red phosphors for white light emitting diodes. [Copyright &y& Elsevier]

Two sequencing batch reactors were synchronously operated to investigate the effect of manganese (II) (Mn) augmentation on aerobic granulation. Reactor 1 (R1) was added with 10 mg/L Mn, while there was no Mn augmentation in reactor 2 (R2). Results showed that R1 had a faster granulation process than R2 and R1 performed better in chemical oxygen demand (COD) and ammonium nitrogen (NH-N) removal efficiencies. Moreover, the mature granules augmented with Mn behaved better on their physical characteristics and size distributions, and they also had higher production of extracellular polymeric substances (EPS) content. The result of three-dimensional excitation and emission matrix fluorescence showed that Mn had the function of causing organic material diversity (especially proteins diversity) in EPS fraction from granules. Polymerase chain reaction and denaturing gradient gel electrophoresis techniques were employed to analyze the microbial and genetic characteristics in mature granules. The results exhibited that Mn augmentation was mainly responsible for the higher microbial diversity of granules from R1 compared with that from R2. Uncultured sludge bacterium A16 (AF234726) and Rhodococcus sp. WTZ-R2 (HM004214) were the major species in R1, while only uncultured sludge bacterium A16 (AF234726) in R2. Moreover, there were eight species of organisms found in both two aerobic granules, and three species were found only in aerobic granules from R1. It could be concluded that Mn could enhance the sludge granulation process and have a key effect role on the biological properties during the sludge granulation. [ABSTRACT FROM AUTHOR]

Abstract: Zizania latifolia was prepared for activated carbons with the method of H3PO4 activation. On the basis of Zizania latifolia activated carbons (ZLAC), adsorption of basic fuchsin (BF) on Fe(III) and Mn(II) modified ZLAC and ZLAC was investigated respectively. Surface morphology and function groups of ZLAC were measured by scanning electron microscopy (SEM), BET surface area and Fourier transform infrared spectroscopy (FTIR). Both of the results from the Fourier transform infrared spectroscopy and Boehm''s titration indicated that the ZLAC owned more acid oxygen functional groups than the alkaline functional groups. The discussions of contact time, dosage and pH were in favor for explaining the adsorption mechanism. The adsorption process agreed well with the pseudo-second-order kinetics (R2 >0.99) and the Langmuir isotherm equation (R2 >0.99), and the maximum adsorption capacity acquired can reach 238.10mg/g. The negative free energy (ΔG) and positive enthalpy (ΔH) indicated a spontaneous and endothermic adsorption process. Results also showed that the adsorption effect of Fe(III) and Mn(II) modified ZLAC was much better than ZLAC. [Copyright &y& Elsevier]

Abstract: The paper presents advantages and limitations of microwave heating in preparation of lotus stalk-based activated carbon by comparing the characteristic and adsorption properties of carbons with microwave (Mic-LSAC) and conventional (LSAC) heating methods employing H3PO4 as chemical agent. Mic-LSAC was produced with radiation power of 700W and radiation time of 15min. LSAC was allowed by single step to get carbonized at 450°C in a muffle furnace for 1h. Both produced carbons showed typical Type IV nitrogen adsorption isotherms. Mic-LSAC had large surface area of 1434m2/g and micropore volume of 1.337cm3/g, while LSAC had surface area of 1220m2/g and micropore volume of 1.191cm3/g. Moreover, Mic-LSAC had higher portion of mesopores than LSAC. Boehm''s titration results and Fourier transform infrared spectra indicated that Mic-LSAC possessed smaller acidic oxygen functionalities. Mic-LSAC had higher pHpzc, more ordered stacking of layer compared to LSAC. For both adsorbents, the adsorption kinetics followed the pseudo-second-order model and the adsorption equilibrium data were very well represented by the Langmuir isotherm. The maximum adsorption capacities obtained at pH 2.80 were 564.97mg/g and 537.63mg/g for Mic-LSAC and LSAC, respectively. The differences of textual and chemical characteristics caused by heating method were related to adsorption capacity. [Copyright &y& Elsevier]

Abstract: The adsorption behavior of Ni (II) on activated carbon prepared from lotus stalks by H3PO4 activation has been investigated. Scanning electron microscopy and BET surface area were characterized to provide insight into the properties of lotus stalks activated carbon (LSAC). The adsorbent prepared was found to have a porous structure with surface area of 1220m2/g. Adsorption results revealed that the removal speed of Ni (II) by lotus stalks derived active carbon was rapid. The pseudo-second-order kinetic model fitted well with kinetic data, showing high determination coefficients (R 2) of over 0.999. The adsorption isotherms of Ni (II) on this adsorbent were well described by Langmuir and the maximum adsorption capacity calculated from Langmuir isotherm model was up to 31.45mg/g. The negative ΔG and the positive ΔH suggested the spontaneous and endothermic nature of the process. The effect of pH and ionic strength and desorption studies could help explain the electrostatic attraction and ion-exchange adsorption mechanism. Desorption studies also represented that LSAC had a good regeneration capacity. The results showed that LSAC could be used to effectively adsorb Ni (II) from aqueous solutions. [ABSTRACT FROM AUTHOR]

Abstract: Nanoporous Au–Ag alloys with different Ag content were prepared by selective dissolution of Ag from Au42Ag58 alloy samples in HNO3 solutions. With gradual dissolution of Ag component, the corroded Au–Ag alloy samples display typical bicontinuous nanoporous structures after dealloying for more than 10min. The as-prepared nanostructured Au–Ag alloys exhibit obviously enhanced catalytic activity towards the electrooxidation of d-glucose as compared with the uncorroded Au42Ag58 alloy. It is of interest that the existence of a tiny amount of silver in the corroded Au–Ag alloys is very advantageous to enhancing their catalytic activity for the electrooxidation of glucose. The new finding was confirmed by the significant enhancement of the catalytic activity of a nanoporous gold (NPG) electrode after modification with a monolayer of Ag atoms underpotentially deposited (UPD). The nanoporous Au–Ag alloys with appropriate amount of Ag and the NPGs modified with Ag UPD monolayers are thus expected to be promising electrocatalysts for the development of glucose sensors and glucose fuel cells. [Copyright &y& Elsevier]

Abstract: The spectroscopic properties of Sm3+-ions in tellurite, fluorophosphate, and fluorine-modified silicate glasses are examined under the excitations at 488nm (Ar+ ion laser) and 1060nm laser. The effect of dopant ion and glass–host interaction, branching ratio of transitions and line shapes of emission lines in the visible region are discussed in view of the ionicity and covalency of hosts. The lifetimes of metastable levels are also reported and the results are explained for designing the visible and UV laser hosts. [Copyright &y& Elsevier]

Abstract: The near infrared spectroscopic properties of Tm3+−Yb3+ co-doped tellurite glasses were investigated using a 980nm laser diode. The 1.81μm emission corresponding to the 3F4→3H6 transition of Tm3+ and the 1.02μm emission of Yb3+ were recorded at room temperature. The effects of Tm3+ and Yb3+ ion concentrations on the emission characteristics and the lifetimes of 1.81μm and 1.02μm were also analyzed. These results indicate that the energy transfer occurred between the Yb3+ and Tm3+ ions in the co-doped tellurite glasses. The luminescence mechanism in Yb3+ and Tm3+ co-doped tellurite glass was also discussed, which is important to develop 1.8μm fiber lasers or 1.8μm and 1.465μm fiber amplifiers. [Copyright &y& Elsevier]

The Er3+–Eu3+-codoped tellurite fibre was pumped at 800 nm (CW) using a Ti–sapphire tunable laser source. The emission spectra at 592 and 613 nm, both attributed to Eu3+ transitions from 5D0→7F1 and 5D0→7F2, respectively, were recorded at room temperature. Although the upconversion fluorescence from the Er3+:4S3/2 level is well known, the observed efficient energy transfer from the Er3+:(2H11/2, 4S3/2) levels to the Eu3+:(5D1, 5D0) levels is not known in the literature. The calculated energy transfer efficiency is approximately 20%. The observed visible emissions point out that the Er3+–Eu3+-codoped tellurite fibre is a potential host material for designing a 589 nm laser for satellite communication and a compact 613 nm fibre laser for medical applications. [Copyright &y& Elsevier]

We herein report a case of a 14-month-old infant who revealed a progressive hearing loss by repeated auditory evoked brainstem responses (ABR) during his 1 year stay in the neonatal intensive care unit (NICU). He was born prematurely with asphyxia, hyperbilirubinemia and respiratory distress. During his 1 year stay in the NICU he was under constant mechanical ventilation. Repeated ABRs over this year initially showed normal waves but subsequently demonstrated progressive hearing impairment (HI) leading finally to no responses. Possible causes of this progressive deafness (PF) include the multiple problems of asphyxia, hyperbilirubinemia and pulmonary disorders. [Copyright &y& Elsevier]

• The D-tagaturonate epimerase (UxaE), which has a C4 epimerization function, catalyzes the synthesis of d -tagatose. • Semi-rational design has optimized UxaE to a 10.8-fold increase in efficiency. • Reshaping the substrate-binding pocket can effectively enhance the 4 epimerization function of the epimerase. d -tagatose, a rare sugar with broad applications in the food and pharmaceutical industries, can be synthesized from d -fructose by epimerases, an approach with significant biosynthesis potential. However, so far there has been only one attempt to engineer tagatose 4‑epimerase through random mutagenesis. The lack of exploration has severely restricted the application of epimerases in the industrial production of d -tagatose. The previous research primarily focused on enhancing the catalytic activity of epimerases through random mutagenesis, with limited understanding of how substrate-adjacent residues affect enzyme efficiency, which was hence the subject of this study. First, using a semi-rational design approach, after three rounds of mutagenesis and screening, the mutant (S125D/S268A/Q124E) of D-tagaturonate epimerase (UxaE) from Thermotoga neapolitana was obtained, which increased d -tagatose production efficiency by 10.8-fold compared to the wild type, with a specific activity of 1505.6 U/g, representing the highest specific activity reported for a UxaE mutant to date. Molecular dynamics simulations showed that the substitution of Ser to Asp-125 enhanced substrate-enzyme interactions, while the substitution of Glu to Gln-124 reinforced the hydrogen bond network around the catalytic residue Glu-128, further reshaping the substrate-binding pocket and enhancing catalytic activity. This study for the first time explored the enhancement of the C4 epimerization function of epimerases by reshaping their substrate-binding pockets, thereby providing a feasible route for the industrial biosynthesis of d -tagatose. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Transparent oxyfluoride glasses doped with Tb3+ were prepared by melt quenching method. The transmittance spectra show the glasses have good transmittance in the visible spectrum region. The emission spectra under 376nm light and X-ray excitations were recorded. Tb3+ doped oxyfluoride glasses show intense green emissions under both excitations. The optimum concentrations of Tb3+ ion are around 8mol% and around 10mol% under 376nm light excitation and X-ray excitation, respectively. The lifetimes of 541nm emission of oxyfluoride glasses doped with Tb3+ are in the range from 2.65ms to 3.02ms. The results indicate that Tb3+-doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event. [Copyright &y& Elsevier]

Metal-free catalysts are widely considered as promising alternatives to traditional metal-based catalysts, which can effectively activate peroxymonosulfate (PMS). In this study, a novel metal-free catalyst, carbonized polypyrrole (CPPy) was synthesized through high-temperature carbonization of PPy, easily achieving the in situ N doping without the addition of nitrogen sources. Tetracycline (TC) was selected as the target contaminant to assess the catalytic activity of the CPPy/PMS system. Enhanced catalytic activity was observed in CPPy/PMS over a wide pH range (3.0–9.0), and the removal rate of TC by CPPy-3/PMS reached 91.3% after 10 min. After regenerating the used catalyst, the catalytic activity was refreshed, implying its stability and recyclability. The catalytic degradation of TC by CPPy/PMS was mainly attributed to a non-radical process. CPPy, as an intermediary, grabbed electrons from the electron-donating groups of TC and transferred them to the PMS molecule. Thereafter, TC that lost electrons was oxidized and degraded, and the O–O bonds of PMS were destroyed by the transferred electrons to form S O 4 2 − and OH−. Moreover, O ⋅ 2 − and 1O 2 were involved in TC degradation. TC degradation pathway was investigated through HPLC-MS analysis. These findings provide a promising strategy for the construction of catalysts for PMS and environmental remediation. Image 1 • Metal-free N-doped material CPPy was prepared without the addition of N sources. • CPPy/peroxymonosulfate showed excellent catalytic degradation of tetracycline. • The in-situ generation of graphitic N is the key of peroxymonosulfate activation. • The tetracycline degradation is mainly attributed to a non-radical process. [ABSTRACT FROM AUTHOR]

Abstract: Trivalent samarium ion (Sm3+) doped SU8 polymer materials were synthesized and characterized. Intense red emission at 645nm was observed under UV laser light excitation. Spectroscopic investigations show that the doped materials are suitable for realizing planar optical waveguide amplifiers. About 100μm wide multimode Sm3+-doped SU8 channel waveguides were fabricated using a simple UV exposure process. At 250mW, 351nm UV pump power, a signal enhancement of ∼7.4dB at 645nm was obtained for a 15mm long channel waveguide. [Copyright &y& Elsevier]