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The optimization of pore characteristics is of pivotal importance for enhancing the capacitive performance of activated carbons (ACs) in supercapacitor applications. This study delved into the impact of porous structures, developed through varying activation temperatures (350–850 ֩C), on capacitive performance of wood derived activated carbons (ACs). Our findings revealed that AC 350 , possessing the highest micropore surface area (S micro) of 903.38 m2 g-1 and a micropore volume (V micro) of 0.43 cm3g-1, exhibited the lowest specific capacitance (SC) of 13 Fg-1. This suggests that a higher SC is not significantly associated with a greater quantity of micropores. Conversely, AC 850 , with a peak S meso of 1472.89 m2 g-1 and V meso of 1.24 cm3g-1, demonstrate a SC of only 83 Fg-1, indicating that the higher SC is not significantly correlated with an increased amount of mesopores either. However, AC 650 displayed an optimal SC of 123 Fg-1, with an ideal S meso /S micro ratio of 2.16 and V meso /V micro ratio of 5.50. This underscores that the superior capacitive performance of ACs based electrode materials is intricately linked to an effective amalgamation of micro- and meso-pores. By strategically manipulating the pore composite structure to augment the charge storage capability of activated carbon electrode materials, we can enhance the energy density of capacitors. This advancement is poised to further propel the application of biomass-derived activated carbon and its composite capacitor technology in energy storage domains. [Display omitted] [ABSTRACT FROM AUTHOR]

The source-to-sink system of the northern South China Sea (SCS) has been widely discussed during the past few decades. Sr–Nd isotope, clay minerals and trace elements were extensively used as the proxies of sediment provenance, however, still little is known about the transport processes and controlling mechanisms on detailed spatiotemporal scales due to the limitations of these methods. Here we put forward the new provenance proxies RAK and RKCN based on major element compositions to study the spatiotemporal changes in sediment provenance since 150 ka mainly from four sites, DLW3101, MD12-3429, ZHS-176 and MD12-3432, which are located on the northern SCS continental slope. Our results show that, spatially, the pathways and intensities of contour currents and gravity flows play important roles in sediment transport. For alongslope processes, the South China Sea Branch of Kuroshio Current (SCSBKC) and the Deep Water Current (DWC) transport sediments from southwestern Taiwan, while the Intermediate Water Current (IWC) can carry sediments from Hainan, the Red River or the Indochina Peninsula. For downslope processes, gravity flows transport materials from the Pearl River delta and shelf to the slope. Moreover, seafloor bathymetry influences sediment transport by altering the pathways of ocean currents. Temporally, the impacts of sea level and monsoon rainfall fluctuations are always superimposed over the last 150 ka. Sea level fluctuations could significantly change the distance from the Pearl River estuary to the slope, while variations in the East Asian summer monsoon (EASM) rainfall would affect continental erosion rates in the source regions. [ABSTRACT FROM AUTHOR]

A series of diterpene-type compounds were synthesized starting from commercially available (−)-carvone. The Michael reaction of (−)-carvone itself delivered four diastereomeric dimers divergently. Following in parallel transformations of reduction, condensation and reductive amination, the corresponding alcohol, oxime and amine were obtained respectively. Particularly, several cage-like structures were obtained via late-stage olefin functionalization. The absolute configurations of the aforementioned compounds were unambiguously determined by NMR spectral, X-ray crystallographic and conformational analysis. Finally, the in-vitro anti-cancer and anti-inflammatory activities of these dimers were tested preliminarily. [Display omitted] [ABSTRACT FROM AUTHOR]

Ammonia is a vital intermediate in the hydrogen desorption process of Metal-N-H system. KH has strong reactivity with NH 3 to form KNH 2. We speculate that KNH 2 is also an intermediate formed during hydrogen desorption of the potassium-doped M-N-H systems. In this research, the dehydrogenation performance of the KNH 2 -doped LiNH 2 and LiH composition was first studied. Compared with the broad dehydrogenation curve of the composite material of LiNH 2 and LiH without the catalyst, the dehydrogenation curve of 0.05 mol KNH 2 -doped composite material was significantly narrowed. The initial and peak dehydrogenation temperature of the composite to which 0.05 mol of KNH 2 was added was lowered remarkably. Besides, the cyclic dehydrogenation properties of the LiNH 2 and LiH system was also significantly enhanced by the introduction of KNH 2. The cyclic conversion of KNH 2 to KH is the main reason for the enhancement of the hydrogen evolution performance of the LiNH 2 –LiH system doped with KNH 2. We found the KNH 2 -doped Li–N–H system exhibits similar dehydrogenation property with that of the KH-doped Li–N–H system. This work proves that KNH 2 plays a key role in improving the hydrogen desorption performances of the potassium-doped M-N-H systems. Image 1 • Hydrogen desorption properties of the KNH 2 -doped Li–N–H system was examined. • Hydrogen desorption kinetics are significantly enhanced by introducing KNH 2. • The dehydrogenation temperature is lowered drastically. • The improved properties induce from the cyclic conversion from KNH 2 to KH. • KNH 2 may be formed during dehydrogenation of the potassium-doped M-N-H system. [ABSTRACT FROM AUTHOR]

Combinatorial problems are a fundamental research subject of theoretical computer science, and for a general graph many combinatorial problems are NP-hard and even #P-complete. Thus, it is interesting to seek or design special graphs for which these difficult combinatorial problems can be exactly solved. In this paper, we study some combinatorial problems for the Farey graphs, which are translated from Farey sequences and have received considerable attention from the scientific community. We determine exactly the domination number, the independence number, and the matching number. Moreover, we derive exact or recursive solutions to the number of minimum dominating sets, the number of dominating sets, the number of maximum independent sets, the number of independent sets, the number of maximum matchings, as well as the number of matchings. Finally, we obtain explicit expressions for the number of acyclic orientations and the number of root-connected acyclic orientations. Since the considered combinatorial problems have found wide applications in diverse fields, such as network science and graph data miming, this work is helpful for deepening our understanding of the applications for these combinatorial problems. [ABSTRACT FROM AUTHOR]

Series of NaBa 0.97 Ce 0.03 B 9 O 15 : x Tb3+, y Sm3+, z Dy3+ are synthesized by the traditional high temperature solid-state method. Ce3+ is used as a sensitizer to improve the spectral properties of Tb3+, Sm3+ and Dy3+ by the way of energy transfer which is proved by the fluorescence decay curves. And the mechanisms of energy transfer from Ce3+ to Tb3+, Sm3+ and Dy3+ are all determined as dipole-dipole interaction. The color of NBB:3%Ce3+, x Tb3+, 0.5%Sm3+ can shift from light violet thought white to yellow. And NBB:3%Ce3+, z Dy3+ can give out white light and move to green field. Moreover, the thermal stability makes NBB:3%Ce3+, 0.2%Dy3+ be a potential candidate for the self-referencing luminescent thermometry. Image 1 [ABSTRACT FROM AUTHOR]

Thin film batteries (TFBs) are receiving increasing interest in the transition stage from current liquid electrochemistry to solid-state future in pursuit of higher energy and power densities. Nevertheless, the fundamental understanding the impacts of the electrode-solid-electrolyte interface engineering and unveiling the correlation between crystallographic texture as well as the electrochemical behavior of electrodes has remained elusive. Herein, the epitaxial growth of LiNi 0.5 Mn 0.3 Co 0.2 O 2 cathode on two rational designed buffer substrates has been studied. The highly textured LiNi 0.5 Mn 0.3 Co 0.2 O 2 thin films with c -axis (003) preferred orientation were successfully fabricated onto the in situ -annealed Pt (111) reconstructed buffer substrate by virtue of direct-current (DC) and radio frequency (RF) magnetron sputtering technologies. The LiNi 0.5 Mn 0.3 Co 0.2 O 2 thin films were also deposited onto the Ti buffer substrate. The effects of the substrate on the structural and electrochemical properties of the LiNi 0.5 Mn 0.3 Co 0.2 O 2 thin film deposited on these two (Pt and Ti) substrates have been both investigated and compared. The deposited LiNi 0.5 Mn 0.3 Co 0.2 O 2 thin film on the Pt substrate exhibited much better electrochemical performance as the sole active cathodes thin film electrodes than the Ti buffered one. The results demonstrate that the Pt/LiNi 0.5 Mn 0.3 Co 0.2 O 2 thin film electrode exhibits a discharge capacity of 84 mA h/g at ambient temperature and shows a stable cyclic performance within 200 cycles. Such interface dominated electrochemical performance behavior is of technological significance. Furthermore, it is indispensable in developing synergistic interfacial engineered design and process control strategy on fabricating more robust batteries with higher energy density and longer cycling stability beyond thin solid ones. Image 1 • The annealing temperature and the texture nature of buffer layer determine the growth and microstructure of NCM thin film. • The lattice matching between the Pt (111) and the deposited NCM (006) layer makes the high quality NCM thin solid cathode. • The crystalline NCM thin film cathode shows much better electrical performance than the amorphous NCM thin film cathodes. [ABSTRACT FROM AUTHOR]

Porcine butyrophilin-like 5 (Btnl5) is a novel member of the butyrophilin family, which consists of immune regulators. The expression pattern and the function of this gene remain unclear. In this study, Btnl5 is identified as a negative regulator of the NF-κB pathway. Our study indicates that Btnl5 is mainly expressed in intestinal epithelial cells (IECs) and expressed in membrane systems. Btnl5 inhibits MyD88-mediated activation of the NF-κB pathway. Btnl5 interacts with TNF receptor-associated factor 2 (TRAF2) and transcription factor p65. Besides, Btnl5 inhibits p65-mediated activation of the NF-κB pathway and inhibits nuclear translocation of p65. These results suggest that Btnl5 may inhibit NF-κB pathway through binding and interfere nuclear translocation of p65. [ABSTRACT FROM AUTHOR]

9 batches of unconfined methane-air deflagration tests were conducted to investigate the influential factors on the deflagration load. The methane-air mixture was filled in the cubic tents with different volumes of 1 m 3 , 8 m 3 and 27 m 3 . Methane concentrations varied from 7.5% to 11.5%, covering both lean and rich combustion regimes. The ground overpressure was recorded by using the piezoresistive sensors. An ideal film was validated before the tests. The effects of the methane concentration and gas volume on the deflagration load were analyzed. Based on the results, a new prediction model for the unconfined methane-air deflagration load was proposed. In addition, the model was compared with some existing models. [ABSTRACT FROM AUTHOR]

Catalytic ozonation is progressively becoming an attractive technique for quick water purification but efficient and stable catalysts remains elusive. Here we solvothermally synthesized highly-dispersed Co 3 O 4 nanocrystals over microscale nitrogen-doping graphene (NG) nanosheets and tested it as a synthetic catalyst in the ozonation of phenol in aqueous solutions. Transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectra and X-ray photoelectron spectroscopy were used to determine its morphology, crystallinity, elemental composition and molecular bonds, respectively. The comparative experiments confirmed the highest catalytic activity and oxidation degree (AOSC) of Co 3 O 4 /NG among four nanocomposites (G, NG, Co 3 O 4 /G, and Co 3 O 4 /NG). Co 3 O 4 /NG also has exhibited the highest degradation rate: complete conversion of a near-saturated concentration of phenol (941.1 mg/L) was achieved within 30 min under ambient conditions with only a small dosage of Co 3 O 4 /NG (50 mg/L) and ozone (4 mg/L, flow rate: 0.5 L/min). It also resulted in 34.6% chemical oxygen demand (COD Cr ) and 24.2% total organic carbon (TOC) reduction. In this work, graphene nanosheets not only functioned as a support for Co 3 O 4 nanocrystals but also functioned as a co-catalyst for the enhancement in phenol removal efficiency. The surface nitridation and Co 3 O 4 modification treatment further improved the removal rate of the phenol pollutants and brought in the higher oxidation degree. Our finding may open new perspectives for pursuing exceptional activity for catalytic ozonation reaction. [ABSTRACT FROM AUTHOR]

29 batches of vented explosion tests were conducted in a 12 m 3 concrete chamber filled with methane–air mixtures to investigate the effects of methane concentration and venting pressure on the development of overpressure inside the chamber. The deflagrations were vented from a square side window with a venting area of 0.64 m 2 upon rupture of the vent cover. The venting pressures were varied by using six different types of vent covers, and determined by performing a numerical simulation. Methane concentrations in the mixed gas varied between 6.5 and 13.5 vol.%, covering both lean and rich combustion regimes. The generation conditions of the four types of overpressure–time profiles with different overpressure transients were summarized. Among the overpressure transients, the Δ P 1 caused by failure of the vent cover and the Δ P 4 resulted from the coupling between acoustic mode and flame were basically dominant. The rate of Δ P 1 rise as well as peak value of Δ P 1 and Δ P 4 showed a same trend of first increasing and then decreasing with the methane concentration from lean to rich. They reached their maximum value at the methane concentration of about 9.5%, whereas the rate of Δ P 4 rise was found to be insensitive to the methane concentration. The peak value of Δ P 1 increased with the venting pressure, while that of Δ P 4 first increased and then decreased as the venting pressure increased. In addition, the rates of Δ P 1 and Δ P 4 rise were both insensitive to the venting pressure. The occurrence of Δ P 4 was depended on the methane concentration and the venting pressure. The differences in the behavior of these overpressure transients suggest their different generation mechanisms. [ABSTRACT FROM AUTHOR]

Silicon (Si) has been perceived as a promising next-generation anode material for lithium ion batteries (LIBs) due to its superior theoretical capacity. Despite the natural abundance of this element on Earth, large-scale production of high-purity Si nanomaterials in a green and energy-efficient way is yet to become an industrial reality. Spray-drying methods have been exploited to recover Si particles from low-value sludge produced in the photovoltaic industry, providing a massive and cost-effective Si resource for fabricating anode materials. To address such drawbacks like volume expansion, low electrical and Li + conductivity and unstable solid electrolyte interphase (SEI) formation, the recycled silicon particles have been downsized into nanoscale and shielded by a highly conductive and protective graphene multilayer through high energy ball milling. Cyclic voltammetry and electrochemical impedance spectroscopy measurements have revealed that the graphene wrapping and size reduction approach have significantly improved the electrochemical performance. It delivers an excellent reversible capacity of 1,138 mA h g −1 and a long cycle life with 73% capacity retention over 150 cycles at a high current of 450 mA g −1 . The plentiful waste conversion methodology also provides considerable opportunities for developing additional rechargeable devices, ceramic, powder metallurgy and silane/siloxane products. [ABSTRACT FROM AUTHOR]

Membrane fouling, which limits the application of membrane bioreactors, has received considerable research attention in recent years. In this work, filtration modeling was performed in combination with surface plasmon resonance (SPR) analysis to investigate the membrane fouling mechanism. Sodium alginate (SA) and bovine serum albumin (BSA) were used to perform dead-end filtration on hydrophilic and hydrophobic poly (vinylidene fluoride) (PVDF) membranes. The initial foulant deposition and layer formation on membranes as well as the interaction between the BSA and SA were comprehensively analyzed. Results indicated that during SA filtration, initial fouling on hydrophilic membranes were primarily attributed to the particle–membrane interactions, while the fouling on the hydrophobic membrane were dominantly caused by the interactions among SA particles. The interaction between BSA and SA led to more severe membrane fouling and hydrophobic membrane was more sensitive to it, especially in the initial filtration process. The SPR results helped clarify the in-situ deposition behavior of BSA and SA particles on the PVDF surface. Compared to SA, BSA adsorbed faster on the PVDF membrane, and specific interactions played an essential role in BSA adsorption, whereas the deposition of SA on PVDF could be easily removed by shear force. Interactions between BSA and SA could alleviate the bonding between BSA and the PVDF membrane. [Display omitted] • Specific interaction plays an important role in BSA adsorption. • BSA generates faster fouling than SA on the hydrophobic membrane. • Interactions between BSA and SA alleviate complete blockage. • Interactions between BSA and SA eliminated the bonding between BSA and membrane. [ABSTRACT FROM AUTHOR]

Aging represents an important health issue not only for the individual, but also for society in general. Burdens associated with aging are expanding as longevity increases. This has led to an enhanced focus on issues related to aging and age-related diseases. Until recently, anti-aging endocrine-therapy has been largely limited to hormone-replacement therapy (HRT) that is associated with multiple side effects, including an increased risk of cancer. This has greatly limited the application of HRT in anti-aging therapy. Recently, the focus of anti-aging research has expanded from endocrine signaling pathways to effects on regulatory gene networks. In this regard, the GHRH-GH-IGF-1/Insulin, TOR-S6K1,NAD + -Sirtuin, P53 , Klotho and APOE pathways have been linked to processes associated with age-related diseases, including cancer, cardiovascular disease, diabetes, osteoporosis, and neurodegenerative diseases, all of which directly influence health in aging, and represent key targets in anti-aging therapy. [ABSTRACT FROM AUTHOR]

Highlights: [•] 3D Co(II) ions modified graphene aerogels were prepared by one-step hydrothermal process. [•] The aerogel electrodes showed hybrid supercapacitor behaviors. [•] The aerogel electrodes exhibited high rate capability and long-term cycling stability. [Copyright &y& Elsevier]

• This is the first systematic study of the keratin family in yak. 53 keratins are identified in yak. • The results show that yak keratins have the same conserved domain and sequence as other species keratins. • The study demonstrates the expression pattern of keratins genes throughout the hair cycle and identifies five different expression patterns. • Nine hub keratin genes are identified by WGCNA method in the whole hair cycle. As the largest subgroup of intermediate filament proteins, keratins are divided into two types of subfamily. Currently, the molecular mechanism of keratins in several animals has been reported but is limited in yak. Here, 53 different kinds of keratins were identified in the yak genome, including 23 type I and 30 type II keratins. Bioinformatics analysis in this study revealed that multiple phosphorylation sites were identified among all the family members. And the subcellular localization of these proteins was predicted to be in the nucleus, cytoskeleton, and cytoplasm. All keratin family proteins were unstable and the scores of instability coefficient were higher than 40. Phylogenetic analysis showed that high consistency results of the sequence conservation and grouping were found in the genomes of yak, sheep, cattle, mouse, rat, and human. Based on the expression patterns obtained from the transcriptome data, keratin genes (KRTs) were grouped into five clusters, and results also showed that KRTs were highly activated in skin tissues during the hair cycle in yak. Among the five clusters, Cluster II contained the most KRTs , which was the main expression pattern of the yak hair follicle cycle, followed by Cluster III. These results indicated the transition period from telogen to anagen and catagen to telogen were highly dynamic in yak. Gene expression correlation analysis showed that KRTs exhibited a strong correlation (mainly positive correlation) throughout the hair follicle development cycle. And the identification of hub KRTs in specific modules related to hair follicle development in this study was performed using the Weight Gene Co-Expression Network Analysis (WGCNA). Specific modules that include KRTs were darkgreen (KRT40), darkgrey (KRT5), turquoise (KRT1 , KRT2 , KRT10), bisque4 (KRT4), thistle2 (KRT9 , KRT39), and yellowgreen (KRT24). The interaction network showed that these genes were found to be related to the regulation of cell cycle, melanogenesis, hair follicle development, keratinocyte proliferation. Our study provides theoretical support for the study of the evolutionary relationship and molecular mechanism of keratin family in B. grunnien. [ABSTRACT FROM AUTHOR]

Abstract: The electrochemical corrosion behaviour of Q235 steels in 3.5wt.% NaCl solutions with sulphide and extracellular polymeric substances (EPS), the two main metabolites of sulphate-reducing bacteria, was separately investigated through potentiodynamic polarisation and electrochemical impedance spectroscopy. Either sulphide or EPS increased the anodic current density by nearly one order of magnitude and negatively shifted the corrosion potential. The effects of EPS at the initial stage of corrosion may be ascribed to the Fe2+-complexing capability and the quickly adsorbed film. Moreover, the feeble protective effect of EPS after 16d of immersion was observed through scanning electron microscopy. [Copyright &y& Elsevier]

Abstract: This paper discusses some Cauchy–Khinchin integral inequalities. Khinchin obtained an inequality relating the row and column sums of 0-1 matrices in the course of his work on number theory. As pointed out by van Dam , Khinchin’s inequality can be viewed as a generalization of the classical Cauchy inequality. Van Dam went on to derive analogs of Khinchin’s inequality for arbitrary matrices. We carry this work forward, first by proving even more than general matrix results, and then by formulating them in a way that allows us to apply limiting arguments to create new integral inequalities for functions of two variables. These integral inequalities can be interpreted as giving information about conditional expectations. [Copyright &y& Elsevier]

Chlorophyll and xanthophyll were extracted from different plants for use as sensitizer colorants; cells were sensitized using chlorophyll, xanthophyll and a mixture of the two pigments. It was found that energy conversion efficiency (η) and maximum output power (P max) were 15.16% and 8.31% higher than that achieved by the linear superposition of the cells sensitized by individual pigments. This indicates that the mixed pigment co-sensitization entails a synergistic effect in the energy transfer of the pigment-sensitized mesoporous TiO2 solar cells. Fluorescence analysis revealed that the electron transfer between chlorophyll and xanthophyll in the mixed pigment co-sensitized mesoporous TiO2 solar cells was similar to that in ‘zigzag chains’ of photosynthesis. [Copyright &y& Elsevier]

Abstract: Background: Disc arthroplasty is gaining popularity for treatment of low-back pain caused by degenerative disc disease (DDD). It can involve total disc replacement or partial disc or nucleus replacement (or augmentation). Compared with total disc replacement, nucleus replacement is less invasive, has less surgical risk, has faster postoperative recovery, and doesn’t “burn bridges” should further surgery be required. However, nucleus replacement has a high risk of implant expulsion because the device is not fixed to the vertebrae. Nubac is the first polyetheretherketone (PEEK)-on-PEEK articulated disc arthroplasty device designed to optimally restore the lumbar anatomy and biomechanics. Methods: ISO 10993 standards were used to evaluate the biocompatibility of the PEEK material. Chemical and thermal–mechanical tests and in vivo study assessed PEEK''s biostability after exposure to high g irradiation and harsh oxidative conditions. Biomechanical tests to evaluate kinematic properties and anatomical restoration of the implanted lumbar motion segments and implant expulsion risk assessments were performed with a human cadaveric model. Because of the novelty of PEEK-on-PEEK as a self-mating articulating material, extensive wear tests were conducted with unidirectional and coupled motions. Static and fatigue strength also were tested. Animal study with a baboon model was conducted with gross, radiographic, biomechanical, and histological evaluations at 6 and 12 months postoperatively. Preliminary clinical data were collected through a prospective multicenter cohort study. Results: PEEK demonstrated exceptional biocompatibility and biodurability. Nubac restored disc height and motion segment range of motion. The unique articulating design of the Nubac demonstrated low risk of implant expulsion in a human cadaveric model. Wear tests showed that the Nubac has minimal wear and compares favorably to other disc arthroplasty materials. The Nubac also had excellent static and fatigue properties for the intended application. The animal study showed that the Nubac caused no adverse local or systematic tissue reaction and there was no detectable wear debris. The preliminary clinical data showed no major intraoperative vascular and neurological complications. There was significant Visual Analog Scale and Oswestry Disability Index score improvement. Conclusions: The preclinical data supported the design rationale, and the preliminary clinical data (level II evidence) on safety and efficacy were encouraging. Clinical Relevance: The Nubac could be a viable first surgical option for patients with back pain caused by DDD. [Copyright &y& Elsevier]

Abstract: We give an almost complete solution of a problem posed by Klaus and Li [A.-L. Klaus, C.-K. Li, Isometries for the vector (p, q) norm and the induced (p, q) norm, Linear and Multilinear Algebra 38 (1995) 315–332]. Klaus and Li’s problem, which arose during their investigations of isometries, was to relate the Frobenius (or Hilbert–Schmidt) norm of a matrix to various operator norms of that matrix. Our methods are based on earlier work of Feng [B.Q. Feng, Equivalence constants for certain matrix norms, Linear Algebra Appl. 374 (2003) 247–253] and Tonge [A. Tonge, Equivalence constants for matrix norms: a problem of Goldberg, Linear Algebra Appl. 306 (2000) 1–13], but introduce as a new ingredient some techniques developed by Hardy and Littlewood [G.H. Hardy, J.E. Littlewood, Bilinear forms bounded in space [p, q], Quart. J. Math. (Oxford) 5 (1934) 241–254]. [Copyright &y& Elsevier]

We obtain optimal equivalence constants for certain families of matrix norms. Our results generalize inequalities of Goldberg [Linear and Multilinear Algebra 21 (1987) 173]. [Copyright &y& Elsevier]