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Ultrasound-based shear wave elastography offers estimation of tissue stiffness through analysis of the propagation of a shear wave induced by a stimulus. Displacement or velocity fields during the process can contain noise as a result of the limited number of acquisitions. With advances in physics-informed deep learning, neural networks can approximate a physics field by minimizing the residuals of governing physics equations. In this research, we introduce a shear wave elastography Fourier feature network (SELFNet) using spatial-temporal random Fourier features within a physics-informed neural network framework to estimate and denoise particle displacement signals. The network uses a sparse mapping to increase robustness and incorporates the governing equations for regularization while simultaneously learning the mapping of the shear modulus. The method was evaluated in datasets from tissue-mimicking phantom of lesions and ex vivo tissue. The findings indicate that SELFNet is capable of smoothing out the noise in phantom lesions with different stiffness and sizes, outperforming a reference Gaussian filtering method by 17% in relative ℓ 2 error, 45% in reconstruction root-mean-square error. Furthermore, the ablation study suggested that SELFNet can prevent over-fitting through the Fourier feature mapping module. An ex vivo study confirmed its applicability to different types of tissue. The implementation of SELFNet shows promise for shear wave elastography with limited acquisitions. In this context, subject to successful translation, it has the potential to be extended to clinical applications, such as the diagnosis of cancer or liver disease. [ABSTRACT FROM AUTHOR]

Magnolia lotungensis is an extremely endangered endemic tree in China. To elucidate the genetic basis of M. lotungensis, we performed a comprehensive transcriptome analysis using a sample integrating the plant's bark, leaves, and flowers. De novo transcriptome assembly yielded 177,046 transcripts and 42,518 coding sequences. Notably, we identified 796 species-specific genes enriched in organelle gene regulation and defense responses. A codon usage bias analysis revealed that mutation bias appears to be the primary driver of selection in shaping the species' genetic architecture. An evolutionary analysis based on dN/dS values of paralogous and orthologous gene pairs indicated a predominance of purifying selection, suggesting strong evolutionary constraints on most genes. A comparative transcriptomic analysis with Magnolia sinica identified approximately 1000 ultra-conserved genes, enriched in essential cellular processes such as transcriptional regulation, protein synthesis, and genome stability. Interestingly, only a limited number of 511 rapidly evolving genes under positive selection were detected compared to M. sinica and Magnolia kuangsiensis. These genes were enriched in metabolic processes associated with adaptation to specific environments, potentially limiting the species' ability to expand its range. Our findings contribute to understanding the genetic architecture of M. lotungensis and suggest that an insufficient number of adaptive genes contribute to its endangered status. [ABSTRACT FROM AUTHOR]

This article presents the design and implementation of a soft X-ray polarized calibration platform based on Bragg's Law and Fresnel's Law, which is used to calibrate low-energy polarization detector(LPD/POLAR-2) that has potential deployment onboard the China Space Station. The platform is equipped with versatile equipment that can generate both completely and partially polarized X-ray beams, and provides precise control over the diffraction angle, achieving the desired polarization degree. It covers the 3–8 keV energy band, with a high fraction of monochromatic light (>93%)(The proportion of monochromatic light is defined as the ratio of the number of photons falling within three times the sigma of the target peak centre value to the total photons.) and good monochromaticity(In this article, we evaluate the monochromaticity of the polarized source using the Full Width at Half Maximum (FWHM) of its all-in-one peak.), and is suitable for calibrating LPD's large-field-of-view soft X-ray polarization detector using its vertically incident and obliquely incident polarized X-rays. The completely and partially polarized X-ray beams generated at 8.0 keV by the calibration platform are used to test the polarization measurement capabilities of the soft X-ray polarized detector and verify the linearity between the calibration source's polarization and the measurable modulation of the polarimeter. [ABSTRACT FROM AUTHOR]

Successful management of lip and perioral trauma requires a nuanced understanding of anatomy and surgical techniques. Surgical correction is particularly challenging in instances of tissue loss, due to a narrow tolerance for aesthetic deformity and highly specialized functions of the perioral region, including facial expression, communication, and oral competence. Restoring continuity of the orbicularis oris musculature is critical for dynamic sphincter function of the upper and lower lips. Lip and perioral tissue symmetry are also critical for aesthetic balance, and failure to restore a natural appearance can adversely affect personal identity, with attendant psychological trauma. This discussion of lip and perioral trauma management encompasses lip and perioral anatomy, evaluation of injuries, reconstructive techniques, and prevention and management of complications. Perioral injuries are classified by size, depth, and extent of injury, and the corresponding reconstructive approaches are a function of complexity. These approaches proceed sequentially up rungs of the reconstructive ladder including primary repair, local flaps, grafting, regional flaps, as well as microvascular free tissue transfers. Procedures may be single stage or require multiple stages or subsequent refinement. Regardless of the defect size or location, the guiding principle of repair in the perioral region is restoring natural function and aesthetic appearance. This still-evolving area of facial plastic and reconstructive surgery lends itself to artistry and technical precision, offering opportunities for further innovation to improve the outcomes of patients with lip and perioral trauma. [ABSTRACT FROM AUTHOR]

To develop an objective standard for defining binary tropical cyclones (BTCs) in the western North Pacific (WNP), two best-track datasets, from the China Meteorological Administration and the Joint Typhoon Warning Center, were adopted for statistical analyses on two important characteristics of BTCs—two TCs approaching each other, and counterclockwise spinning. Based on the high consistency between the two datasets, we established an objective standard, which includes a main standard for defining BTCs and a secondary standard for identifying typical/atypical BTCs. The main standard includes two requirements: two coexisting TCs are a pair of BTCs if (i) the separation distance is ⩽ 1800 km, and (ii) this separation maintains for at least 12 h. Meanwhile, the secondary standard defines a typical BTC as one for which there is at least one observation when the two TCs approach each other and spin counterclockwise simultaneously. Under the standard, the ratio of typical BTCs increases as the BTC duration increases or the minimum distance between the two TCs decreases. Then, using the JTWC dataset, it was found that there are 505 pairs of BTCs during the period 1951–2014, including 328 typical BTCs and 177 atypical BTCs, accounting for 65.0% and 35.0% of the total, respectively. In addition, a study of two extreme phenomena—the maximum approaching speed and the maximum counterclockwise angular velocity in typical BTCs—shows that the configuration of the circulation conditions and the distribution of the BTCs favor the formation of these extreme phenomena. [ABSTRACT FROM AUTHOR]

Real-time observation and control of particle size and production rate in microfluidic devices are important capabilities for a number of applications, including the production, sorting, and manipulation of microbubbles and droplets. The production of microbubbles from flow-focusing microfluidic devices had been investigated in multiple studies, but each lacked an approach for on-chip measurement and control of microbubble diameter in real time. In this work, we implement a closed-loop feedback control system in a flow-focusing microfluidic device with integrated on-chip electrodes. Using our system, we measure and count microbubbles between 13 and 28 μ m in diameter and control their diameter using a proportional–integral controller. We validate our measurements against an optical benchmark with R 2 = 0.98 and achieve a maximum production rate of 1.4 × 10 5 /s. Using the feedback control system, the device enabled control in microbubble diameter over the range of 14–24 μ m. [ABSTRACT FROM AUTHOR]

Objectives: (a) Determine the demographic and medical risk factors for patients who presented with unilateral idiopathic sudden sensorineural hearing loss (ISSNHL); (b) identify treatments that patients underwent; (c) evaluate the adequacy of follow‐up and compliance with long‐term hearing rehabilitation. Methods: Retrospective review of patients who presented with unilateral ISSNHL between January 1998 and December 2017 at a tertiary care academic medical center. Results: Two hundred‐four patients met inclusion criteria. Of these, 129 (63.2%) did not undergo treatment at an outside hospital prior to our evaluation. In this subgroup, the average pretreatment pure tone average (PTA) was 61.9 ± 2.5 dB (dB). The most common treatment was oral steroids and was recommended in 76 patients (59.9%). Patients also underwent intratympanic (IT) steroid injections (7.2%) or oral steroids followed by salvage IT injections (19.4%). Mean follow‐up duration was 17.9 (±29.2) months, and posttreatment PTA (45.6 ± 2.6 dB) was significantly better than baseline (P <.001). In this cohort, hearing amplification was infrequently recommended. Less than 20% of patients reported active hearing amplification use at their most recent visit. At follow‐up, 90 patients (69.8%) reported subjective improvement in hearing after treatment. Only 55 patients (42.6%) showed improvement in PTA compared to their pretreatment audiograms. Conclusion: Many patients with ISSNHL experienced audiometric improvement after treatments, but most had persistent hearing loss. The duration of follow‐up was short. Most patients did not use long‐term hearing amplification. Future studies are needed to identify factors that contribute to reduced follow‐up and low compliance with hearing amplification use in ISSNHL. Level of Evidence: 2c. [ABSTRACT FROM AUTHOR]

A facile method for the one-pot synthesis of 1,2-diarylindoles under transition-metal-free conditions is described. Cyclohexanones were used as the aryl sources via the dehydrogenative aromatization process. One C–C and two C–N bonds were selectively formed via a domino reaction. This protocol provides a convenient approach for the construction of valuable bioactive 1,2-diarylindoles from readily available cyclohexanones, α-hydroxyketones and anilines. [ABSTRACT FROM AUTHOR]

Metal-free oxidative cyclization for the one-pot synthesis of benzo[d]imidazo[2,1-b]thiazoles from 2-aminobenzothiazoles and cyclic ketones is described. Elemental sulfur combined with molecular oxygen as the benign co-oxidant was found to be unique and highly effective to promote this transformation without the aid of any metal salts. Various cyclic ketones smoothly reacted with 2-aminobenzothiazoles to give functional benzo[d]imidazo[2,1-b]thiazoles in good to very high yields, which thereby demonstrated the synthetic convergence of this methodology. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient strategy for the synthesis of 9-aryl-substituted acridines from cyclohexanones and 2-aminobenzophenones in the presence of a palladium catalyst. Molecular oxygen is applied as a green oxidant. Various cyclohexanones acted as the aryl source to construct the nitrogen-containing heterocycles through a condensation/cyclization/tautomerization sequence. [ABSTRACT FROM AUTHOR]

Modification of wood with phenol-formaldehyde (PF) and melamine-formaldehyde (MF) resins is known as an efficient strategy to improve wood's dimensional stability, mechanical strength, and durability. This study systematically examined the effects of these types of modifications on the thermo-oxidative decomposition and combustion behavior of Scots pine ( Pinus sylvestris L.) sapwood treated to weight percent gains ranging from 10 to 55 %. Thermo-gravimetry results showed that treatment with PF and MF reduced the decomposition rate, thereby thermally stabilizing the wood. Bench-scale cone calorimetry results indicated that the treated wood exhibited longer ignition times and yielded more char than the untreated control. Treatment with PF did not substantially change the heat release of wood, but led to a considerable increase in CO and smoke production. New compounds in the smoke from the treated wood were identified as phenols and its derivatives resulted from incorporation of PF resin as evidenced by pyrolysis/gas chromatography/mass spectrometry of the volatile organic compounds. Treatment of the wood with MF resulted in greater heat release due to complete combustion; however, smoke production was significantly suppressed. These findings demonstrate that both treatments cause different fire risk patterns: smoke issues for the PF-treated wood and heat hazard for the MF-treated wood. [ABSTRACT FROM AUTHOR]

An efficient strategy for carbazole synthesis from arylureas and cyclohexanones under transition metal-free conditions has been developed. The combined use of potassium iodide and iodine could significantly improve the reaction efficiency to provide 2,6-disubstituted 9-arylcarbazoles in moderate to good yields. In this kind of transformation, the whole carbazole moiety (except the nitrogen atom) comes from two equivalents of cyclohexanones. [ABSTRACT FROM AUTHOR]

An efficient procedure for pyrido[1,2-a]benzimidazole preparation from 2-aminopyridines and cyclohexanones under metal-free conditions is described. Non-aromatic cyclohexanones were used as the aryl source via a dehydrogenation–aromatization process using molecular oxygen as the green oxidant. [ABSTRACT FROM AUTHOR]

The Fenton reaction is supposed to play a key role in the initial wood degradation by brown rot fungi. Wood was modified with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and glutaraldehyde (GA) to various weight percentage gains in order to study if these types of modifications are able to reduce wood degradation by Fenton reagent. Veneers modified with higher concentrations (1.2 and 2.0 mol l-1) of both chemicals exhibited minor losses in mass and tensile strength during treatment with Fenton reagent, which shows restrained oxidative degradation by hydroxyl radicals. The decomposition rate of H2 O2 was lower in the Fenton solutions containing modified veneers than in those containing unmodified controls. More CO2 evolved in systems containing unmodified veneers than in systems with modified veneers, indicating that modification protected wood from mineralisation. The reason for the enhanced resistance of modified wood to the Fenton reaction is attributed to impeded diffusion of the reagent into the cell wall rather than to inhibition of the Fenton reaction itself. The results show that wood modification with DMDHEU and GA is able to restrain the degradation of wood by the Fenton reaction and can explain why modified wood is more resistant to brown rot decay. [ABSTRACT FROM AUTHOR]

The investigation of phase transition in powdered materials by dynamic mechanical analysis (DMA) is not straightforward because powders are difficult to prepare in a solid compact form without altering their structure and properties. In this study, a material pocket (MP) method has been applied to provide physical support to powdered samples for DMA testing (MP-DMA). Poplar wood strips and four types of wood particles [native wood flour (WF), α-cellulose (αC), holocellulose (HC), and particles without hemicelluloses (HR)] were treated with an ionic liquid (IL), 1-ethyl-3-methylimidazolium chloride ([Emim]Cl), to a weight percent gain (WPG) of 36%. Results show that all four [Emim]Cl-treated wood particles exhibited three apparent transition peaks over the measured temperature range. Paracrystalline cellulose, hemicelluloses, and lignin all exhibited a glass transition temperature ( Tg) at approximately 85°C due to the plasticizing effect of [Emim]Cl. The transition peak at a higher temperature may be due to the melting of crystalline cellulose in [Emim]Cl. MP-DMA is an effective tool for direct monitoring the phase transition of powdered lignocellulosics. This provides new insight into the interactions of ILs and cell wall polymers, and the method established can be easily extended to other systems based on powdered samples. [ABSTRACT FROM AUTHOR]

Background Elevated intracranial pressure (ICP) is an inciting factor for cerebrospinal fluid (CSF) leaks and can be measured by CSF pressure (CSFP) monitoring. Current CSFP literature is limited to the assessments of opening pressure. This study reinvestigates a previously discussed monitoring approach that evaluates continuous CSFP parameters, physiologic measurements, and treatment outcomes in patients undergoing endoscopic repair of spontaneous CSF leaks. Methods Retrospective review of patients undergoing endoscopic endonasal repair of spontaneous CSF leaks. All participants had a lumbar catheter placed for 24-hour continuous preoperative pressure monitoring, and 24 hours of continuous monitoring starting 48 hours after repair. In addition to patient characteristics, mean and peak CSFP, pulse waveform amplitudes (PWAs), and related parameters were calculated. Results Twenty-five patients underwent monitoring between 2004 and 2013, with a mean follow-up of 526 days. The mean age was 49.2 years, the mean body mass index (BMI) 38.5, and 8 of 25 (32%) had obstructive sleep apnea. Although mean CSFP and PWA decreased after the repair, mean peak CSFP increased by 1.56 cmH2O (1.15 mmHg). Six patients (24%) had elevation in their CSFP >25 cmH2O (18.4 mmHg) for a minimum of 4% of the recording time. Based on their continuous pressure monitoring data, 9 patients (36%) underwent treatment for high ICP, either with acetazolamide or a ventricular shunt. There were no CSF leak recurrences. Conclusion Continuous perioperative CSFP monitoring provides valuable insight into multiple physiologic parameters. Systematic continuous CSFP monitoring can identify individuals in need of ICP-lowering therapy, possibly improving the outcomes in CSF leak repair surgeries. [ABSTRACT FROM AUTHOR]

The modification of wood with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) is an efficient strategy to improve its dimensional stability and durability during its service period. In this study, oak wood ( Quercus mongolica L.) was treated with DMDHEU and the combustion behavior of the treated wood was examined. The bench-scale thermogravimetry and cone calorimetry showed that the treatment with DMDHEU alone enhanced the flammability of wood, but a combined treatment with DMDHEU and traces of magnesium chloride as a catalyst lowered the flammability to the level of untreated wood. In full-scale fire tests for flooring materials, it could be confirmed that both the untreated and treated woods have similar combustion behavior and can be classified as Dfl-S1 (capable of resisting a small flame and, for a certain period, a heat flux attack; the total smoke production is limited). Accordingly, further fire-retardant treatments may be required if DMDHEU-treated wood is used in public areas. [ABSTRACT FROM AUTHOR]

The in situ thermoplasticization of poplar wood with ionic liquids (ILs) has been investigated. The thermoplastic deformation of wood samples treated with four types of ILs at various concentrations was determined through nonisothermal compression tests by means of a rotational rheometer. Results show that increasing the concentration of ILs reduced softening temperature and increased deformation compared to the untreated control. Scanning electron microscopy revealed that plastic deformation of wood cells from the applied compression stress varied, depending on cell type, and occurred without cell wall fracture. X-ray diffraction analysis of compressed wood showed that wood treated with ILs exhibits a greater crystallinity index than the untreated control. The recovered strain in compressed samples decreased with increasing temperature and concentration of ILs to 18% weight percent gain (WPG) and then decreased slightly to 36% WPG. In treated samples, the combined wood/IL blends demonstrated less thermal stability than wood and ILs alone. Results also show that plastic deformation of IL-treated wood resulted in viscous buckling of unfractured cell walls. This deformation mode likely resulted from the disintegration of intermolecular and intramolecular hydrogen bonding between cell wall polymers through the combined effect of ILs, pressure, and high temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Removal of hemicellulose reduced water absorption and thickness swelling. [•] Removal of lignin caused the highest tensile modulus and storage modulus. [•] WPCs with αC had the highest tensile strength, elongation at break, and toughness. [Copyright &y& Elsevier]

Abstract: This study investigated the effect of wood cell wall composition on the rheological properties of wood particle/high density polyethylene (HDPE) blends. Four types of wood particle with different compositions were prepared: native wood flour (WF), hemicellulose-removed particle (HR), holocellulose (HC), and α-cellulose (αC). The particles were characterized in terms of functional groups, crystallinity, particle size, and morphology. Wood particle/HDPE composite formulations were melt-blended using a twin-screw extruder and the rheological properties of the blends were characterized using a Haake microcompounder, torque rheometer, capillary rheometer, and rotational rheometer. Results show that removal of lignin and/or hemicelluloses changed the crystallinity and microstructure of cell walls. These changes in cell wall composition and morphology altered the melt torque, shear stress, viscosity, and storage and loss moduli. Specifically, the melts viscosity decreased as αC/HDPE>HR/HDPE>WF/HDPE>HC/HDPE. This demonstrates that the composition of cell walls substantially affect the rheological behavior of wood particle/HDPE composites. [Copyright &y& Elsevier]

Highlights: [•] Bituminous plug expansion joint materials containing high rubber granule content. [•] Low modulus and improved flexibility at low temperature. [•] Permanent deformation resistance is susceptible to larger rubber granule content. [•] Introduce a reliable indicator for relaxation performance evaluation. [Copyright &y& Elsevier]

Highlights: [•] Asphalt plug joints are damaged and failed due to different mechanisms. [•] Joint structure optimization reduces stress concentration. [•] Binder properties are related to joint performance. [•] Performance based material specifications can be developed. [Copyright &y& Elsevier]

In order to effectively harness varieties of mechanical waves or vibrations for the purpose of monitoring and/or powering, developments in responsive materials and conversion technologies are taking place driven by the world's current and future demands. One of the most popular novelties of the last two decades is represented by hydrogel‐ or ionogel‐based flexible iontronics which constitute a wide family of innovative smart (self‐powered) mechanoreceptors relevant for various applications such as personal health care, identity and safety monitoring, intelligent human‐machine operation interfaces, underwater listening and communication, and so on. Cellulosic gels (CGs), as a promising green substitute for fossil fuel‐derived materials, are extensively studied due to the possibility to choose between different cellulose types and to formulate networks chemically or physically, according to the adaptability requirements for each target application. The aim of this review is to showcase the cellulose structural versatility and to provide a summary of the principles during the formulation of CGs used for mechanosensing and mechanical energy scavenging, as well as their practical applications. Such an outlook of current challenges and overall prospects will serve as a stimulus for research on CG‐based mechanoreceptors in the future. [ABSTRACT FROM AUTHOR]

This study investigated the effects of an ionic liquid, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), as a doping salt, on the properties of resulting solid biopolymer electrolytes (SPEs) based on all-cellulose composites. The conductivity of the resulting SPEs increased with the [Bmim]Cl loading. Both incubation time and chemical loading affected the tensile properties of the SPEs. The SPEs prepared under the optimum processing conditions exhibited a tensile strength and conductivity of 18.2 MPa and 1.28 × 10 S cm, respectively, when tested at room temperature. FTIR and XPS spectra showed that the concentration of [Bmim]Cl in the SPEs was greater at the surface than at the interior. Treatment with [Bmim]Cl resulted in a decrease in the crystallinity and thermal stability of the SPEs as evidenced by XRD and TGA analyses. This study demonstrates that treatment of cellulosic materials with the ionic liquid [Bmim]Cl can create biomass-based SPEs with high conductivity, improved mechanical properties, good thermal stability and easy processability. [ABSTRACT FROM AUTHOR]

Scots pine sapwood was treated with glutaraldehyde (GA) in aqueous solution using magnesium chloride as a catalyst in order to evaluate the durability towards weathering. Infrared spectroscopy suggested that GA treatment increased the photo-stability of lignin during artificial weathering of micro-veneers in a QUV over 168 h; photo-protection increased with increasing GA concentration. In comparison with the unmodified controls, GA-modified pine micro-veneer strips exhibited a lower tensile strength loss measured in a zero-span mode in the course of weathering. During 18 months of outdoor exposure, GA-modified pine wood boards exhibited a lower moisture content and water uptake than the unmodified ones. GA treatment also clearly restricted the penetration of blue stain fungi into deeper layers of wood. On the macroscopic scale, the surface of the GA-modified boards was significantly smoother due to less erosion, cracking and minor peeling of tracheids. Scanning electron microscopy further revealed that individual tracheids were detached from the cell compound and then washed away from the unmodified wood surface, whereas tracheids on surfaces of GA-modified wood remained in the tissue compound but displayed many axial and transversal cracks. [ABSTRACT FROM AUTHOR]

The first palladium-catalyzed diarylamine formation from nitroarenes and cyclohexanone derivatives using borrowed hydrogen is described. Various diarylamines were selectively obtained in good to excellent yields. The reaction tolerated a wide range of functionalities. The nitro reduction, cyclohexanone dehydrogenation, and imine formation and reduction were realized in a cascade without an external reducing reagent and oxidant. [ABSTRACT FROM AUTHOR]

Scots pine sapwood ( Pinus sylvestris L.) and European beech wood ( Fagus sylvatica L.) were treated with glutaraldehyde (GA) in aqueous solution in the presence of magnesium chloride as a catalyst to evaluate the durability improvement towards staining and rot fungi. The GA modified specimens were dipped in a spore suspension of the blue stain fungus Aureobasidium pullulans and incubated for 8 weeks. The growth on both pine and beech wood was restrained, when the weight percent gain (WPG) of the specimens was above 7%. Under this condition, GA-modified beech wood did not suffer any mass loss after incubation with the white rot fungus Trametes versicolor. The threshold to prevent decay of beech and pine specimens towards the brown rot fungus Coniophora puteana was at a WPG of only 3%. GA treatment to a WPG over 6% protected the Scots pine stakes from soft rot decay during 32 weeks' exposure according to ENv 807 (2001). [ABSTRACT FROM AUTHOR]

Abstract: Both glutaraldehyde (GA) and 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) can crosslink the cell wall polymers and dimensionally stabilize wood particles and the treated wood particles are thus expected to enhance the properties of the resulting wood particle/polypropylene composites. Compared to the composites filled with untreated particles, treatments of wood particles with both GA and DMDHEU showed a great reduction in water uptake and dimensional swelling of the resulting composites up to 39% and 46%, respectively. Both the flexural and tensile moduli increased due to wood particles treatments with GA and DMDHEU. Treatments of wood particles improved the tensile strength but moderately weakened the flexural strength and Charpy impact strength of the composites. Dynamic mechanical analysis and microscopy suggested an improved interfacial compatibility between wood particles and matrix due to GA and DMDHEU treatments. Chemical treatment resulted in smaller particle sizes and altered microscopic fracture appearance after composite production as compared to untreated particles. Morphological changes were attributed to embrittlement of wood particles, which may negatively influence the mechanical properties of the resulting composites. [ABSTRACT FROM AUTHOR]

Abstract: This study describes the effects of wood modification with modified 1,3-dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) on the coating performance of solvent- and water-borne finishes. Although the basic colour of wood was slightly changed due to the modification, modified and unmodified samples did not display any colour differences after coating with translucent stains. Blocking of coated wooden substrates (degree of adhesiveness) was dependant on the type of finish system and, in a few cases, on the wood substrate. For all wood substrates, both treated and untreated, solvent-borne alkyd finish penetrated into the surface layers of the wood cells, while water-borne acrylic finishes spread only on the wood surfaces. The solvent-borne alkyd finish dried much more slowly on wood substrates than did the water-borne acrylics. Modification with mDMDHEU did not affect the drying rates of the finishes tested. The wet adhesion depended on the finish systems tested and on the pre-treatment of the wooden substrate. With regard to the pre-treatment, wet adhesion of one water-borne and the solvent-borne finish systems was significantly enhanced through precedent modification with mDMDHEU. The other two water-borne finish systems showed a higher degree of wet adhesion. This study demonstrates that modification of the wood substrate with mDMDHEU is compatible with both water-borne and solvent-borne finish systems and improves their wet adhesion on the wood surface. [Copyright &y& Elsevier]

Background: Numerous studies have indicated a growing prevalence of hyperuricemia. Elevated levels of serum uric acid (SUA) have been established as influential factors in conditions such as obesity, metabolic syndrome, diabetes mellitus, gout, and cardiovascular disease. Overweight and obesity are closely related to an increase in SUA. Our objective is to demonstrate the mediating role of liver enzyme in the correlation between body mass index (BMI) and SUA. Methods: A total of 5925 adults aged 18 to 65 were included in this cross-sectional study. Logistic regression and mediation analysis were used to investigate the relationship between BMI and hyperuricemia as well as liver enzyme levels. Standard methods were used to determine the biochemical indexes, including SUA, liver enzymes, and blood lipids in the collected samples. Results: The study revealed that the prevalence of hyperuricemia was 28.0%. Furthermore, the prevalence of overweight and obesity was as high as 48.5%, with 70.7% of this subgroup presenting with hyperuricemia. There was a positive correlation between BMI and hyperuricemia, and elevated levels of liver enzymes (ALT, AST, GGT) were associated with a higher risk of hyperuricemia. The study also observed a positive correlation between BMI and liver enzymes (ALT, AST, GGT). The study findings suggested that ALT, AST, and GGT played significant mediating roles in the relationship between BMI and SUA. Specifically, the unadjusted model revealed that ALT and GGT accounted for 22.12% and 18.13% of the mediation effects, respectively. Conclusions: The study found that BMI is associated with hyperuricemia, where liver enzyme abnormalities may have a mediating role. It is suggested that being overweight or obese may affect liver enzyme levels, leading to increased SUA levels. Controlling weight and liver enzyme levels may help prevent and treat hyperuricemia. [ABSTRACT FROM AUTHOR]

Highlights Bamboo‐based composite, being an eco‐friendly green material, has garnered widespread utilization across diverse sectors including construction and domestic appliances owing to its impressive strength, innate aesthetic appeal, and wear resistance. However, it tends to crack at bonding interface between bamboo and the brittle resin adhesive due to stress concentration, reducing its mechanical properties and lifespan. To address this issue, the epoxy‐based polyhedral oligomeric silsesquioxane (POSS) was incorporated to modify the phenol‐formaldehyde (PF) resin and improve the interfacial bonding strength. And the results showed that the incorporation of 5% epoxy‐POSS could markedly increase the impact and flexural strength of the modified PF resin by 75.7% and 27.6%, respectively, in contrast to the original PF resin. Moreover, the dry and wet shear strength of bamboo‐PF composites bonded by the POSS modified PF resin adhesive was also apparently improved by 17.03% and 28.55%, respectively. The increased toughness and bonding strength were mainly attributed to the nano‐effect of POSS and good compatibility and cross‐linking reaction with the PF resin, which helped dissipate energy and avoid stress concentration within the PF resin and at the bonding interface. This study aims to address the cracking problem of bamboo‐based composites and extend their longevity in architectural and domestic applications. Epoxy‐POSS disperse well in PF resin due to its unique multi‐epoxy structure. Epoxy‐POSS can react with PF resin and effectively improve its toughness. Nano‐effect and cross‐linking effect enable dissipate energy and disperses stress. Modification increased bonding strength and decreased interfacial cracking. [ABSTRACT FROM AUTHOR]

• Double-layered WPPC filled with EG and APP was prepared. • The double-layered WPPC with EG in surface layer showed better fire retardant properties. • The char residue rate of double-layered WPPC with EG in surface layer was greatly increased. • The surface layer with EG of WPPC could protect the base layer from decomposition. • The flexural strength of double-layered WPPC with EG in surface layer was improved. Expandable graphite (EG) and ammonium polyphosphate (APP) distributed in different layer of wood fiber and polypropylene composites (WPPC) were prepared. The results of cone calorimetry showed that the layered distribution of EG and APP considerably improved the fire retardancy of the overall composites, and the char residue rate was 41.9%, which increased by 200% compared with that of single-layered WPPC. Moreover, a more firm and compact physical structure char in the base layer formed due to protection of EG in the surface layer. The flexural strength and modulus of double-layered WPPC also increased compared with these of the single-layered WPPC with EG. [ABSTRACT FROM AUTHOR]

Electromagnetic radiation pollution has become more serious in our daily life. The portable, flexible materials with an ultrahigh electromagnetic interference shielding effectiveness (EMI SE) are highly desirable to meet the needs of different applications. In this study, such a material was prepared by combining cellulose paper substrate with an effective electroless plating, which involved successive steps of 3-aminopropyltriethoxysilane (APTES) modification, PdCl2 activation and nickel coating deposition. The interaction mechanism among cellulose paper, APTES and PdCl2 was researched by FTIR and XPS measurements. According to SEM and XRD analyses, the nickel particles, with an average grain size of 14.742 nm, were densely deposited on the surface of cellulose paper, which formed excellent conductive paths. The electrical conductivity and EMI SE increased with an increase in plating time. When the plating time was 60 min, the sheet resistance was 97.1 mΩ/sq, and the EMI SE reached 44.1 dB in a frequency range of 8.2–12.4 GHz. The deposited Ni coating improved the self-cleaning and corrosion resistance properties of the cellulose paper. This work provides a sustainable, multifunctional, flexible cellulose paper-based shielding material that can achieve large-scale production. [ABSTRACT FROM AUTHOR]

Technologies enabling passive daytime radiative cooling and daylight harvesting are highly relevant for energy-efficient buildings. Despite recent progress demonstrated with passively cooling polymer coatings, however, it remains challenging to combine also a passive heat gain mechanism into a single substrate for all-round thermal management. Herein, we developed an optical wood (OW) with switchable transmittance of solar irradiation enabled by the hierarchically porous structure, ultralow absorption in solar spectrum and high infrared absorption of cellulose nanofibers. After delignification, the OW shows a high solar reflectance (94.9%) in the visible and high broadband emissivity (0.93) in the infrared region (2.5–25 μm). Owing to the exceptional mass transport of its aligned cellulose nanofibers, OW can quickly switch to a new highly transparent state following phenylethanol impregnation. The solar transmittance of optical wood (OW-II state) can reach 68.4% from 250 to 2500 nm. The switchable OW exhibits efficient radiative cooling to 4.5 °C below ambient temperature in summer (cooling power 81.4 W m−2), and daylight heating to 5.6 °C above the temperature of natural wood in winter (heating power 229.5 W m−2), suggesting its promising role as a low-cost and sustainable solution to all-season thermal management applications. • Combining phenylethanol and delignified wood was first achieved with switching between radiative cooling and solar heating. • The OW exhibits efficient radiative cooling to 4.5°C below ambient temperature in summer (cooling power = 81.4 W m−2).• • The OW exhibits daylight heating to 5.6 °C above the temperature of natural wood in winter (heating power = 229.5 W m−2). • Delignification and solvent impregnation are used to achieve cyclic thermal management properties. • The material we used — wood is obviously green, renewable and degradable. [ABSTRACT FROM AUTHOR]

Chemical modification is an efficient strategy for improving wood quality; however, for some fast-grown wood species unwanted shrinkage occur upon treatment with alkaline solution. This study was devised to reveal the shrinkage behavior of poplar and radiata pine woods treated with 5, 10, 15 and 20 % alkaline sodium silicate (SS) solutions. Wood treated with sodium hydroxide (SH) solution adjusting to the same pH as the specific SS solution was used as a reference sample. The weight loss, chemical components analysis, and confocal microscopy revealed that treatments with SS caused considerable reductions in hemicellulose and acid-insoluble lignin (AIL) of poplar wood up to 51 % and 21 %, respectively. In contrast, such reductions of the SS-treated radiata pine wood were only 13 % and 2 %, respectively. Consequently, shrinkage of poplar wood in the tangential- and radial-directions reached up to 22 % and 11 % respectively. However, such shrinkage for radiata pine was less than 2 % in either direction. The crystallinity index of poplar and radiata pine woods after treatment increased up to 35.3 % and 4.8 %, respectively, attributable to removal of the amorphous fraction. The scanning electron microscopy displayed that treatments had minor effect on the cell structure of radiata pine, but brought about significant collapse of poplar cells. The above results show that radiata pine is more chemically stable to alkaline treatment than poplar. [ABSTRACT FROM AUTHOR]

Sustainable low-cost cellulose-based electronics has exhibited brighter prospects. In this study, a laminated felt-like electromagnetic shielding material was prepared by using cellulose paper as the matrix through the self-foaming effect in electroless nickel plating process in which an efficient palladium-free activation was conducted that alkaline sodium borohydride (NaBH 4) reduced nickel ions into nickel cluster to initiate the plating process. NaOH concentration in NaBH 4 solution, pH of the plating bath and the plating time affected the thickness, metal deposition and surface resistance of the electromagnetic shielding material. By understanding the morphology, inner structure, chemical component and thermal stability, the pH in the plating solution is a key for the preparation. When the pH was 8.51, the electromagnetic shielding effective reached 65 dB in the frequency ranges of 9 kHz to 1.5 GHz, which could shield more than 99.99% electromagnetic radiation. This work offers a novel and feasible path to develop functional cellulose-based materials. Unlabelled Image • A felt-like cellulose-based material was prepared via a novel electroless plating. • A palladium-free activation was conducted the plating bath. • The electromagnetic shielding effectiveness reached 65 dB. • A low-cost and sustainable way in development of shieling materials was given. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose-based superhydrophobic surfaces with CuS nanoparticle were prepared. • Superhydrophobic surfaces exhibited excellent photothermal performance. • The actuators based on superhydrophobic structures showed rapid light-driven motion. • The Marangoni effect and vapor jet flow were the motion mechanisms of the actuators. Among stimuli-responsive actuators, light-driven hydroplaning actuators have attracted significant attention because of their controllable and contactless nature. However, manufacturing actuators with rapid dynamic responses to a single stimulus remains challenging. Herein, inspired by rove beetles and water striders, we developed superhydrophobic light-driven actuators based on the in situ growth of copper sulfide on cellulose nanofiber and subsequent modification with octadecyltrimethoxysilane. The actuators exhibited excellent superhydrophobicity (water contact angle of 160.6°) and the water contact angle was maintained above 150° under various harsh conditions (acid/base immersion, ultraviolet irradiation, heat treatment, and sandpaper abrasion). Under near-infrared (NIR) irradiation (808 nm, 1.4 W cm−2), excellent photothermal performance was achieved, with a photothermal-induced temperature change of 81.0 °C. Based on the mechanisms of superhydrophobicity, the Marangoni effect, and vapor jet flow, the light-driven actuators exhibited a rapid dynamic response (response time of 0.5 ± 0.2 s), ensuring fast linear motion (velocity of 8.7 ± 0.7 mm s−1) and flexible rotation (angular speed of 2.4 rad s−1) under NIR irradiation. Moreover, complex motions such as S-shaped, triangular, and circular motions were achieved by combining linear motion and rotation, which could facilitate obstacle avoidance, smart transportation, and contactless delivery. [ABSTRACT FROM AUTHOR]

Developing sustainable and lightweight structural materials is a promising strategy for reducing carbon emissions in transportation and buildings. However, producing high‐performance bulk structural materials from sustainable biomass materials while maintaining excellent mechanical strength remains a major challenge, especially for further scale‐up. Herein, a scalable and robust bottom‐up strategy is reported to fabricate bulk wooden plate (W‐plate) with a typical "brick‐and‐mortar" structure from engineered wood particles via moderate delignification and in situ LiCl/DMAc treatment followed by hot‐pressing. The W‐plate constructed by delignified wood particles and regenerated cellulose nanofibers can achieve a confluence of mechanical strengthening and toughening by the ordered lamination structure and multiscale cellulose micro/nanofiber crosslinking interactions, resulting in high flexural strength (225.17 ± 12.18 MPa) and high fracture toughness (4.01 ± 0.53 MPa m0.5) while maintaining a low density (1.34 g cm−3), superior to typical metals and ceramics. Moreover, the W‐plate exhibits advantageous thermal properties, including a low thermal expansion coefficient (<19 × 10−6 K−1) and a high storage modulus (>7.5 GPa) compared to those of petroleum‐based polymers. Coupled with abundant and renewable raw materials, all‐cellulose components, and scalable and recyclable fabrication, the W‐plate can potentially be used as a high‐performance, cost‐effective, and environmentally friendly alternative for engineering applications. [ABSTRACT FROM AUTHOR]

Nacre‐inspired materials with combined high strength and toughness have been widely developed and utilized for various engineering applications. However, existing preparation techniques suffer from intricate processes, high energy‐consumption, and lack of scalability, all of which collectively impede the efficient production of three‐dimensional materials. Here, a viable strategy is reported for the efficient and scalable production of bulk nacre‐mimetic materials, drawing inspiration from the intricate structures found in both nacre and wood. The prepared millimeter‐thick wooden artificial nacres (WANs) exhibit the presence of multi‐hierarchical lamellar structures, organic bridges, and micro‐asperities. Those features lead to the WANs exhibiting impressive mechanical performances, presenting excellent bending strength (≈93.31 MPa), toughness (≈7.40 MPa m1/2), tensile strength (≈122.59 MPa), and work of fracture (≈4.61 MJ m−3). In addition, owing to the low density (≈1.59 g cm−3), the WANs show much higher specific mechanical properties compared to nacre and related artificial nacre materials. Considering both its production process and exceptional properties, this material holds great promise for practical applications within the realm of engineering and structural fields. [ABSTRACT FROM AUTHOR]

Nano‐ and micro‐SiO2 particles (termed nSiO2 and mSiO2, respectively) were incorporated in the shell layer of a coextruded wood flour/high density polyethylene composite (WF/HDPE) to improve the mechanical properties and inhibit creep behavior. The effects of loading content, particle size, and surface treatment of the silica with vinyl trimethoxy silane (VTS) were investigated on the properties of the resulting coextruded WF/HDPE composites. Scanning electron microscopy revealed proper interfacial adhesion between the core and shell layers. nSiO2 exhibited higher reinforcement efficacy than that of mSiO2 for the shell‐layer materials. Incorporation of the VTS‐treated nSiO2 caused an increase in flexural‐ and impact strength of the coextruded composites by 29% and 57%, compared to the non‐silica filled coextruded WF/HDPE controls, respectively. Incorporation of nSiO2, either untreated or VTS‐treated, enhanced creep resistance of shell layer materials; however, only VTS‐nSiO2 worked for the coextruded composites. These findings demonstrate that filling with silica, particularly VTS‐treated nSiO2, in the shell layer substantially and economically reinforces coextruded shell/core‐structured WF/HDPE composites. POLYM. COMPOS., 40:1576–1584, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A new procedure is presented for the synthesis of pyrido[1,2-a]benzimidazoles. [ABSTRACT FROM AUTHOR]

In living spaces where wood is commonly used for both construction and decoration, it is crucial to minimize electromagnetic pollution and the risk of fire. In this study, we applied aniline treatment to wood in situ and examined its impact on electromagnetic shielding and fire resistance. By enabling in situ polymerization and the deposition of polyaniline particles within the wood, we enhanced the wood's conductivity while maintaining its porous structure, thereby improving its ability to absorb microwaves. The results indicated that wood species with low density exhibited higher electromagnetic shielding efficiency after treatment due to their greater polyaniline loading. Specifically, an specific electromagnetic shielding efficiency up to 65.8 dB cm−3 g−1 was achieved on the cross sections of treated wood. Furthermore, the total heat release and smoke production decreased by 43.9% and 66.7%, respectively, while the wood char mass increased by 66.3%. The results demonstrated that polyaniline-treated wood with bifunctional features could serve as a promising candidate in this field. [ABSTRACT FROM AUTHOR]

Abstract: Title compounds [(III), (V), (VII), and (IX)] are catalyst‐free under base‐promotion synthesized starting from readily available materials. [ABSTRACT FROM AUTHOR]

Ultra-high density large-sized Al:ZnO sputtering targets were prepared by hot isostatic pressing(HIP). Studies were conducted on the characteristics of the microstructure of the targets and the photoelectric properties of the deposited film prepared by medium-frequency magnetron sputtering. Experiments showed that, compared to 98% density target, HIP process had no apparent influence on the change of grain dimension of the targets. However, a reduction of the quantity and size of the porosities in the target matrix was recognized and led to an improvement in the uniformity of resistance and thickness and IR transmittance of the deposited film. In this paper, the favorable machining allowance associated to the thickness of the HIPed targets, due to the oxygen-loss layer, was suggested by developing the empirical formula. [ABSTRACT FROM AUTHOR]

Sandwich-structured panels, composed of two surface layers of wood flour/high-density polyethylene composite (WPC) and a core layer of linear low-density polyethylene (LLDPE), were prepared by hot-press. The single-layer WPC panels were used as controls, with wood flour contents ranging from 55 to 84%. The sandwich-structured panels showed an improvement in both flexural and impact strength of up to 42% and 77%, respectively, and water absorption was considerably reduced compared to the controls. The LLDPE core layer did not cause substantial change in creep and relaxation behavior, but resulted in an increase in the linear coefficient of thermal expansion. [ABSTRACT FROM AUTHOR]

Invar36 alloy is a low expansion alloy, and the triply periodic minimal surfaces (TPMS) structures have excellent lightweight, high energy absorption capacity and superior thermal and acoustic insulation properties. It is, however, difficult to manufacture by traditional processing methods. Laser powder bed fusion (LPBF) as a metal additive manufacturing technology, is extremely advantageous for forming complex lattice structures. In this study, five different TPMS cell structures, Gyroid (G), Diamond (D), Schwarz-P (P), Lidinoid (L), and Neovius (N) with Invar36 alloy as the material, were prepared using the LPBF process. The deformation behavior, mechanical properties, and energy absorption efficiency of these structures under different load directions were studied, and the effects and mechanisms of structure design, wall thickness, and load direction were further investigated. The results show that except for the P cell structure, which collapsed layer by layer, the other four TPMS cell structures all exhibited uniform plastic collapse. The G and D cell structures had excellent mechanical properties, and the energy absorption efficiency could reach more than 80%. In addition, it was found that the wall thickness could adjust the apparent density, relative platform stress, relative stiffness, energy absorption, energy absorption efficiency, and deformation behavior of the structure. Printed TPMS cell structures have better mechanical properties in the horizontal direction due to intrinsic printing process and structural design. [ABSTRACT FROM AUTHOR]

A novel, environmentally friendly, biomass-based modification technique utilizing carboxymethylation-activated alkali lignin (CAAL) and glutaraldehyde (GA) is proposed to enhance the physical and mechanical properties of poplar and fir wood. Water-soluble CAAL was prepared by modifying alkali lignin (AL) with sodium chloroacetate following low-temperature activation under a NaOH/urea system. AL is a biomass-based material from industrial by-products. As such, it does not rely on fossil resources nor emit volatile compounds that might limit its range of application. The successful preparation of CAAL was demonstrated by Fourier transform infrared spectroscopy (FTIR), 1H nuclear magnetic resonance spectroscopy (NMR), and 13C NMR, and the changes in structure were analyzed by 2D-heteronuclear singular quantum correlation (2D-HSQC), 31P NMR, and gel permeation chromatography (GPC). The following characteristics of the modified wood samples were investigated in detail: weight percent gain (WPG), bulking, anti-swelling efficiency (ASE), water absorption rate (WAR), leachability of the modifier, microstructure, and mechanical properties. Water immersion results demonstrated that the CAAL/GA hybrid modifier enhanced ASE to 41.3% and 31.5% for fir and poplar, respectively, at a concentration of 15 wt.%. Furthermore, the WAR of fir was reduced by nearly three times to 30.7%, compared to that of a control sample treated solely with GA. GA-treated samples showed high brittleness, whereas both poplar and fir showed enhanced modulus of rupture and elasticity following treatment with the CAAL/GA hybrid modifier. [ABSTRACT FROM AUTHOR]

Rubberwood was modified using a two-step process involving impregnation with maleated lignin (ML) followed by densification. The effects of ML modification and densification on the physical and mechanical properties of modified wood were studied. The successful preparation of ML was confirmed using Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. In addition, scanning electron microscopy was used to characterize the densified rubberwood structure, which featured fully compressed cell walls and cell lumina filled with ML. The rubberwood modification resulted in a more uniform structure and increased density compared to untreated wood. Further, water immersion and moisture absorption experiments revealed thickness swelling of only 27.7% and 20.9%, a reduction of nearly 76% and 55%, respectively, compared to the densified wood that was only impregnated with water. The ML modification can alleviate the embrittlement of wood caused by densification. The modulus of rupture and modulus of elasticity of ML-treated and densified wood improved by nearly 54% and 200%, respectively, compared to untreated wood. Therefore, the synergistic treatment strategy can contribute to the high-value utilization of low-quality rubberwood. [ABSTRACT FROM AUTHOR]

Plantation-grown juvenile wood species are extensively used as raw materials in the Chinese wood industry. The weathering performances of the wood are crucial for outdoor application. Two of the most important plantation-grown juvenile woods, poplar (Populus × euramericana cv. '74/76ʼ) and Chinese fir (Cunninghamia lanceolata Hook), were sliced into thin veneers and compared in this study to observe their weathering performance during exposure to UV alone for 504 h and UV/water for 168 h. The color difference, weight loss, and tensile strength loss of both veneers all increased with exposure time. Scanning electron microscopy showed that the initial structural deterioration originates from the corner of the middle lamella and pit, followed by cell separation, cell wall thinning, deformation, and collapse. Fourier transmission infrared spectroscopy, electron resonance spectrometry and X-ray photoelectron spectroscopy revealed a decrease in lignin-based infrared absorption intensity and radical generation, as well as an increase in O/C ratio throughout the exposure. Water spray considerably accelerated deterioration by washing away the degraded fragments, thereby exposing the fresh substrate underneath. Compared to poplar wood, Chinese fir showed durable structural integrity but more darkening during weathering. These findings reveal the anatomically structural weak phase and photo-degradation performance of two plantation-grown woods during weathering. The results of this work may facilitate the proper external use and further photo-stabilization treatment of plantation-grown juvenile wood products. [ABSTRACT FROM AUTHOR]