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Hexagonal boron nitride (h -BN) materials with excellent physicochemical stability and processibility have been considered as promising engineering materials. However, their practical applications are rather limited by the difficulty in constructing the well-bonded h -BN ceramic. Herein, we present a reaction welding strategy for facile preparation of well-bonded h -BN fibers (BNFs) network by using ethanolamine (ETA) containing alcoholic hydroxyl and primary amine groups as crosslinking agent. The formed >B-O-H 2 C-H 2 C-H 2 N|→B< bond bridges through the esterification and intramolecular coordination (N|→B) reactions between ETA molecules and BNFs containing surface hydroxyls, play an essential role in the construction of the thermodynamically stable >B-N-B< covalent bond between BNFs. Based on this synthetic strategy and a room-temperature molding process followed by a calcination step, a series of resilient BNFs ceramics with high processibility, typical diamagnetism, low dielectric constant (∼ 2.1) and loss, good resistance to temperature different, corrosion, oxidation and abrasion are produced. Besides, they also exhibit excellent strain and damage tolerance, the maximum compression strain and strength can reach up to 38% and ∼ 33 MPa, respectively. Significantly, the deliberately designed BNFs vessel can be successfully used for the alloying of high melting point metals, showing both structural/chemical robustness and good reusability. This ingenious design for well-bonded BNFs network not only is a good model for exploring the welding way for h -BN powders, but also opens up numerous opportunities for practical applications. • A well-bonded boron nitride fibers network is prepared via chemical welding approach. • Ethanolamine (ETA) with bifunctional groups is selected as crosslinking agent. • Bond bridges are formed through esterification and intramolecular coordination reactions. • BNFs ceramics with processibility and excellent physicochemical stability are obtained. [ABSTRACT FROM AUTHOR]

Biochar synthesized from algal biomasses acts as an efficient adsorbent to remove tetracycline (TC) from aqueous solutions. In this study, a mixture of Enteromorpha (EN) and Chlorella vulgaris (CV) was pyrolyzed at 500 °C, then activated with NaOH at 800 °C to prepare composite biochar (EC A -B). The effects of TC concentration (50–500 mg·L−1), pH (3–11), temperature (30 °C–50 °C), and contact time (0–960 min) on TC absorption were investigated. Results revealed that in aqueous solutions, the biochar (EC 4:1 -0.5)prepared with CV and EN at the mass ratio of 4:1 and the impregnation ratio of 0.5 had the optimal TC adsorption capacity (Q m = 376.878 mg·g−1). The removal rate of EC 4:1 -0.5 remained above 80 % after five cycles. The surface area of EC 4:1 -0.5 (583.329 m2·g−1) increased by three and four times that of EN and CV, respectively. Intraparticle diffusion was considered as the major limitation for the adsorption of TC onto EC 4:1 -0.5. This investigation provides a method for the synthesis and optimization of algal biomass-based activated carbon for the absorption of organic pollutants in wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Because they have a high application potential in the thermal management of insulation environments, high-quality hexagonal boron nitride (h-BN)-based multiphase ceramics have been highly desired. However, so far, their synthesis is still full of challenges. Here, a kind of boron nitride nanosheets (BNNSs)/glass (GS) composite ceramics was prepared by a pressureless sintering method at a lower temperature of 900 °C. Due to a tightly bonded interaction between BNNSs and GS, the formed BNNSs/GS ceramics exhibit excellent multifunction performance. They have an outstanding compressive strength in the range of 19 ∼ 64 MPa and Vickers hardness ranging from 50 to 179 HV. For the BNNSs/GS ceramics with BNNS's filling fraction of 90 wt%, their maximum side-surface TC values are 12.01 ± 0.18 W m−1 K−1 at 25 °C and 13.64 ± 0.37 W m−1 K−1 at 300 °C, respectively. In the ultra-high frequency range of 26.5 ∼ 40 GHz, the dielectric constant values of the BNNSs/GS ceramics are primarily between 2 and 3, and the corresponding loss tangent values are < 0.3. In addition, based on the remarkable integrity of their structure, these BNNSs/GS ceramics exhibit outstanding thermal-shock stability and prominent thermal management capacity during lots of heating/cooling-testing cycles. Therefore, we believe this kind of BNNSs/GS ceramic system will have great application potential in the new-generation thermal management and/or insulation packaging fields. [ABSTRACT FROM AUTHOR]

Achieving high energy storage performance at high power density is expected in lithium ion capacitors (LIC), but currently it is limited by the mismatched kinetics between capacitor-type cathodes and battery-type anodes. Herein, carbon nanotube (CNT)-mesoporous carbon (mpC) sponge is an elastic three-dimensional network and prepared by self-assembling phenol functionalized melamine-based micelles on the surface of CNTs and a carbonization process. The porous structures of the mpC layers can be tailored (key factors including the pore ordering degree, coating thickness) to investigate the effects of microstructures on electrochemical properties. Due to the densely packed ordered open mesopores with straight/short channels (13.2 nm) and high N (5.28 at%) and O (5.69 at%) doping, CNT-mpC sponge cathodes possess high specific capacitances of 142 F/g (0.1 A/g). The full carbon LICs (CNT-mpC//CNT) with pure CNT sponges as anodes can deliver a high energy density of 111.8 Wh/kg at 325 W/kg. Even at an ultrahigh power density of 32500 W/kg, our LICs still achieve a satisfactory energy density of 30.7 Wh/kg. We provide a structure design for high power LIC cathodes, and our CNT-mpC sponges are promising in other energy storage systems for high performances at high power density. CNT-mpC sponge cathodes consisting of elastic 3D networks and large amounts of densely packed ordered mesopores with short channels achieve high lithium ion capacitor performances. [Display omitted] [ABSTRACT FROM AUTHOR]

This clinical report describes a conservative approach to improve an unesthetic implant-supported crown and peri-implant mucosal recession around a malpositioned, 1-piece implant in the maxillary right central incisor region by using digital technology. In such clinical situations, the implants are usually removed because of an unpredictable definitive esthetic outcome. However, this clinical report describes the preservation of such a compromised implant by improving the esthetic outcome with a connective-tissue graft, and a digital approach used a 1-step preformed zirconia coping technique with an appropriate emergence profile. [ABSTRACT FROM AUTHOR]

The rehabilitation of facial esthetics when transitioning from a failing dentition in a patient with maxillary protrusion is challenging. This clinical report described such a patient treated with an immediate cross-arch implant-supported fixed prosthesis. The ideal virtual upper lip position was used to predict the sagittal and vertical position of the restoration. A stackable device was fabricated to guide the osteotomy and implant placement. [ABSTRACT FROM AUTHOR]

Complete arch subperiosteal implant-supported prostheses present challenges in terms of effective cleaning, leading to the accumulation of biofilm on their intaglio surfaces. The association between different intaglio surface morphologies and biofilm accumulation on complete arch subperiosteal implant-supported prostheses is unclear. The purpose of this in vitro study was to investigate the correlation between the intaglio surface of complete arch subperiosteal implant-supported prostheses and biofilm accumulation. Sixty-eight complete arch subperiosteal implant-supported prostheses were fabricated with varying interimplant distances and pontic morphologies. Four different types of pontic morphologies were included: saddle, flat, scalloped, and ovate. To simulate biofilm accumulation, a green aerosol was sprayed onto the intaglio surface. Dental floss was used to clean the colored spray from the intaglio surface. The intaglio surfaces of prostheses were then scanned with an intraoral scanner. The biofilm areas were identified and calculated by using a 3-dimensional macroscopical quantification method. The distances between adjacent implants and transmucosal height were measured. The correlation between interimplant distances and biofilm areas, and the correlation between the biofilm areas and transmucosal height, were analyzed using the Spearman test. Furthermore, a generalized estimating equation (GEE) was employed to examine the relationship between pontic morphology and biofilm area, adjusting for location, cantilever, implant distance, and transmucosal height (α=.05). A significant correlation was found between the biofilm area and transmucosal height (correlation coefficient=0.208, P <.001). A significant increase in biofilm accumulation was observed in the saddle group compared with the 3 groups in GEE Models I and II. Flat pontics and ovate pontics have significantly lower biofilm retention. Moreover, transmucosal height plays a significant role in biofilm accumulation in the pontic area. [ABSTRACT FROM AUTHOR]

A digital technique for fabricating a periodontal splint is presented. The lingual surface of periodontally compromised mandibular anterior teeth is captured and registered to form the emergence profile of the periodontal splint. An accurate periodontal splint is fabricated for mandibular anterior teeth with increased mobility after scaling and root planing. [ABSTRACT FROM AUTHOR]

• This study promoted the cycling of carbon and nitrogen in wastewater systems. • The "adsorption-catalysis-adsorption" strategy improved the recovery of waste. • Improved quality of bio-oil obtained with regenerated catalyst. • The maximum adsorption capacity of regenerated bio-char was 554.38 mg·g−1. This study proposes an "adsorption-catalysis-adsorption" strategy to improve the recycling capacity of bio-char, which has implications for improving bio-char utilization and reducing greenhouse gas emissions. A porous bio-char (EPAC) was prepared and used for effective methylene blue (MB) adsorption. The adsorbent after MB adsorption was used to fabricate a new carbon catalyst (EPMCC), which exhibited an excellent catalytic capacity for low N/O bio-oil. The nitrogen content of the bio-oil catalyzed by EPMCC decreased from 34.46 wt% to 17.04 wt%, and the hydrocarbon content increased from 15.52 wt% to 29.09 wt% compared to the pyrolysis of Enteromorpha clathrate alone. The used EPMCC was then regenerated to obtain a new EPMNC adsorbent with a high specific surface area (1097.99 m2·g−1). The maximum adsorption capacity of EPMNC was 554.38 mg·g−1, and the adsorption mechanisms involved electrostatic interactions, π-π interactions, and hydrogen bonding. This study promotes the cycling of carbon and nitrogen in organic wastewater systems containing nitrogen. [ABSTRACT FROM AUTHOR]

The sea cucumber Apostichopus japonicus is an economically important marine species in China, and understanding the mechanisms underlying its gonad development is crucial for successful reproduction and breeding. In this study, we performed transcriptome comparisons and analyses of A. japonicus gonadal and non-gonadal tissues to identify genes and molecular pathways associated with gonadal development. We also supplemented the annotation of the A. japonicus genome. Collectively, results revealed a total of 941 ovary-specific genes and 2499 testis-specific genes through different expression analysis and WGCNA analysis. The most enriched pathways in ovary and testis were "DNA replication" and "purine metabolism", respectively. Additionally, we identified key candidate gene modules that control gonad development and germ cell maturation, with CDT1 and DYNC2LI1 serving as hub genes. Our findings provide important insights into the gonadal development system of A. japonicus and offer valuable references for further research on reproductive biology in this marine invertebrate species. [Display omitted] • Comparative analyses of gene expression in sea cucumber gonadal and non-gonadal tissues • Key candidate gene modules specifically expressed by females and males gonad were screened. • The ovarian module with CDT1 as the core gene may affect ovarian development through the pre-replication complex. [ABSTRACT FROM AUTHOR]

Severe air pollution remains a problem in developing countries such as India and China owing to unfavourable winter climate conditions that encourage the diffusion of air pollutants. Although city lockdowns can alleviate serious air pollution, they incur significant social costs. This study explored the effect of China's COVID-19 lockdown on air pollution. Machine learning was utilised to eliminate weather-related fluctuations in air pollutant concentrations, and two difference-in-difference models were employed to estimate the effects of general epidemic prevention and enhancement measures on air pollution and evaluate the total impact of city lockdown on air pollutant concentrations. By carefully examining the proportion of these effects in the overall impact, this study analysed the cost-effectiveness of city-level lockdown measures on air pollution. Results indicate that city lockdowns significantly reduced the concentrations of five air pollutants: NO2 (−28.3 %), PM10 (−21.41 %), PM2.5 (−15.83 %), CO (−8.66 %), and SO2 (−4.2 %). The contributions of the enhancement measures are 41.82 % for PM2.5, 42.66 % for PM10, −4.04 % for CO, and 31.83 % for NO2. This suggests that city lockdowns may not be cost-effective compared to general epidemic prevention measures. Thus, this study recommends limited city lockdown measures for severe air pollution, similar to the general epidemic prevention measures. • Machine learning can correct the bias generated by directly applying DID models in situations of high data fluctuations. • City-lockdown may not be cost-effective compared to general epidemic prevention measures. • City-lockdown can reduce NO2, PM10, and PM2.5 pollution, however, we must be vigilant against the rise of ozone O3. [ABSTRACT FROM AUTHOR]

Accurately assessing the impact of climate changes on tree growth or forest productivity is vital to better understand global carbon cycles. Here, we carried out dendroclimatological research on Yezo spruce ( Picea jezoensis var. microsperma ) along an elevation gradient in two sites to investigate the effect of rapid warming on spruce growth in northeast China. Results indicated that trees at two low-elevation sites had significantly wider ring widths and higher basal area increment (BAI) compared with high-elevation sites. Ring widths and BAI of Yezo spruce at low elevations showed a clear growth increase during the 1940s–1970s followed by a significant decline after 1980. However, trees at high elevations showed a relatively stable growth during the 1940s–1970s followed by a significant increase after 1980. Rapid warming after 1980 increased the radial growth of Yezo spruce at high-elevation sites, but reduced tree growth at low-elevation sites. Winter precipitation and growing season temperature were positively correlated with radial growth of Yezo spruce at high elevations, but negatively correlated with tree growth at low elevations. A clear pattern of growth and growth-climate relationship changed in 1980. The temperature threshold for determining the impact of climate on Yezo spruce could change with latitude or site. Difference in drought caused by warming may be the main reason for the opposite response of tree growing at different altitudes in northeast China. The mechanism of rapid warming driving contrasting growth at different elevations should also be investigated in other tree species in NE Asia. In the context of future climate warming, our findings are of great significance for tree growth in assessing forest dynamics and carbon cycling. [ABSTRACT FROM AUTHOR]

This work reports a novel thermophilic β-glucosidase (TN0602) from Thermotoga naphthophila RKU-10, demonstrating exceptionally high catalytic selectivity (100%) for the exclusive synthesis of prebiotic galactotrisaccharides (GOS3) in a high volumetric production yield of 23.28 g L −1 h −1 (higher than the highest value ever reported) at pH 6.5 and 75 °C, with milk processing waste lactose as both the galactosyl donor and acceptor. A comparative study with commercial β-galactosidase from Aspergillus oryzae (AO) with respect to reaction kinetics, enzyme-substrate thermodynamic binding (substrate induced fluorescence quenching) and molecular docking simulation studies showed that β-glucosidase TN0602 has a deep catalytic “pocket” with a narrow entrance that prevents simultaneous access of lactose and GOS3 to the catalytic site, explaining its distinct catalytic specificity and reaction kinetics. The findings revealed in this work offer an improved understanding of how enzyme protein structure determines catalytic specificity, which serves as new knowledge to engineer β-glucosidase for the biosynthesis of designer GOS. [ABSTRACT FROM AUTHOR]