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In order to find an explanation for the mechanism in a plasma operated with an alternating voltage, or rather a square wave voltage, such a plasma was investigated. It was found that Penning ionization, charge transfer, and photoionization played a minor or even no role in the soft ionization mechanism of a FµTP. If the collision of plasma gases with air does not contribute to soft ionization, it should also be possible to use a separated plasma for soft ionization. Preliminary investigations show that it is possible to ignite a diagnosis gas with a plasma gas even when there is a barrier such as glass between those gases. A temporally and locally limited potential must be produced at the outer surface to achieve this. This potential should be sufficient to ionize the environment softly and to be able to use this so-called closed µ-tube plasma as a new ionization source. [ABSTRACT FROM AUTHOR]

The soft ionization mechanism of helium-based plasma seems to be understood while it still remains challenging in argon-based plasma, although many studies have used argon plasmas as a soft ionization source with good ionization efficiencies. In this study, helium, argon, krypton, and xenon were fed into the same discharge geometry, a flexible micro-tube plasma (FµTP), to determine the ionization mechanisms. The FµTPs operated with the named noble gases obtained comparable ionization efficiencies by MS measurements. The optical emission results showed that N2+ were the dominant ions within the helium-FµTP and noble gas ions were dominant for the other plasmas. These ions support the development of excitation and eventually stop at the end of the capillary. Therefore, Penning ionization and charge transfer between plasma and ambient air/analytes in the open atmosphere have been proven not to be the primary soft ionization mechanism. Furthermore, it was found that photoionization played a minor role in soft ionization. Using helium as a diagnosis gas in front of the discharge capillary nozzle of the FµTP, where the sample is usually positioned, shows that helium can be ignited by all of these FµTPs. This demonstrates that the excitation of a diagnosis gas as well as the ionization of analytes is independent of the type of the discharge gas. An alternative mechanism that a transient potential created by the ions is responsible for the soft ionization is subsequently proposed. [ABSTRACT FROM AUTHOR]

We construct a lot of optimal or near-optimal [ n , k , d ] 9 Hermitian self-orthogonal codes for k ≤ 3 using norm codes and matrix combinatorial construction method. As an application, we construct nine families of entanglement-assisted quantum error-correcting codes. Some of these codes can achieve q-ary linear EA-Griesmer bound with better parameters than those in the literature. [ABSTRACT FROM AUTHOR]

The Pleurotomarioidea, commonly referred to as slit shells, constitute one of the most ancient and enduring lineages within the phylum Mollusca, with its fossil record tracing back to the Upper Cambrian epoch. Its rareness and evolutionary antiquity surpass even that of the nautilus. In this study, we conducted the first transcriptome sequencing and analyses of Entemnotrochus rumphii (Schepman, 1879), a representative species of Pleurotomarioidea. Full-length transcriptome sequencing of E. rumphii was performed using the PacBio Sequel II platform with SMRT technology. A total of 64.38 gigabytes of data and 964,550 polymerase reads were generated, resulting in 28,068,998 subreads after data filtering. After de-duplication, correction, and clustering, we identified 19,273 genes. Additionally, next-generation sequencing was performed on 11 tissues of E. rumphii. This investigation provides a detailed portrayal and analytical scrutiny of its transcriptomic landscape. [ABSTRACT FROM AUTHOR]

This study, based on the Simufact Welding analysis software, established a three-dimensional finite element computational model according to actual welding conditions. Using a combined volumetric heat source, we analyzed the magnitude and distribution of residual stress after laser arc composite welding of dissimilar aluminum alloys, and validated the results with experimental data. The influence of different preheating temperatures on the variation rule of residual stress in each part of the weldment was explored. The results showed that the calibration results of the combined volumetric heat source model were ideal, and that the simulation results of transverse and longitudinal residual stress were in good agreement with the actual results. The average residual stress in the heat-affected zone (HAZ) of the 5083-H112 aluminum alloy was about 190 MPa, which is close to the yield strength of the base metal at room temperature (193 MPa); the average residual stress at the weld seam was about 230 MPa; and the average residual stress in the HAZ of the 6063-T6 aluminum alloy was about 80 MPa. In addition, preheating before welding has a positive effect on reducing residual stress after welding. The optimal preheating temperature for the 5083-H112 aluminum alloy is about 170°C, and for 6063-T6 aluminum alloy it is about 220°C. [ABSTRACT FROM AUTHOR]

This paper studies the effect of flow rate control modes on VRB performance based on a validated numerical model. Four modes were put forward, i.e., constant flow rate, variable flow rate with equal anolyte and catholyte (Variable modes I and III) and variable flow rate with unequal anolyte and catholyte (Variable mode II). Under the optimal condition (80 mA/cm2 current and 85% state of charge, SOC), the charging efficiency under the Variable mode II is 0.59% higher than that under the constant flow, while 0.45% and 0.85% higher than those under Variable modes I and III, respectively. The charging efficiency improvement could be largely ascribed to anolyte and catholyte flow adjustment independently, which balances the pump power needed and concentration overpotential loss, benefitting the reduction of total power loss. Moreover, when the charging current is 120 mA/cm2, the maximum SOC of tank under Variable modes I, II, and III increase by 7.63%, 6.41%, and 13%, respectively, in comparison with that under the constant flow rate. The significant increase under Variable mode III is due to an introduction of new objective function (pseudo power loss function), which limits the concentration overpotential difference between anolyte and catholyte, extending time to reach cut-off voltage. [ABSTRACT FROM AUTHOR]

In this paper, MIG welding–brazing was employed to join a 1.5-mm-thick 6060 aluminum alloy and a 2-mm-thick galvanized steel, using a 1.2-mm ER4043 welding wire as the filler. The microstructure, phase structure, and element distribution of the welded joint interface layer were analyzed using SEM, XRD, and EDS. The tensile strength of the joint and the hardness distribution of the interface layer were tested. The study found that when the welding current was around 60 A, the interface layer formed optimally, and the tensile strength of the welded joint reached a maximum value of approximately 200 MPa. During the welding process, an intermetallic compound (IMC) Fe2Al5 with lower free energy was formed at the joint interface. As aluminum atoms continuously diffused toward the steel side and reacted with iron, a compound FeAl3 precipitated on the side closer to aluminum. [ABSTRACT FROM AUTHOR]

Due to the BCS theory, hydrogen, the lightest element, would be the prospect of room-temperature superconductor after metallization, but because of the difficulty of the hydrogen metallization, the theory about hydrogen pre-compression was proposed that the hydrogen-rich compounds could be a great option for the high Tc superconductors. The superior properties of TmH6, YbH6 and LuH6 indicated the magnificent potential of heavy rare earth elements for low-pressure stability. Here, we designed XTmH12 (X = Y, Yb, Lu, and La) to obtain higher Tc while maintaining low pressure stability. Most prominently, YbTmH12 can stabilize at a pressure of 60 GPa. Compared with binary TmH6 hydride, its Tc was increased to 48 K. The results provide an effective method for the rational design of moderate pressure stabilized hydride superconductors. [ABSTRACT FROM AUTHOR]

Clogging in the submerged entry nozzle is a common concern during the continuous casting of Al-killed steels, deteriorating the steel quality and impeding the continuity of mold operations. Water experiments were carried out to investigate the multiphase flow in the mold under different nozzle clogging modes. Bubble measurement was achieved by projection methodology using a high-speed camera. The LES-VOF-DPM model was developed based on size distributions of bubbles obtained from water modeling, to evaluate the effects of nozzle clogging on bubble capture by solidifying shell and slag-metal interface behaviors. The results show that clogging at the nozzle groove inhibits the bubble break-up by turbulent flow. Bubbles remaining in large sizes float vertically, leading to concentrated impacts on the slag-metal interface. Clogging at two nozzle ports increases the entry velocity under a constant casting speed. Due to the broken effect of the strong turbulent flow, 9.23 pct of the bubbles are smaller than 0.5mm. Small bubbles tend to reach a narrow face following the entry flow and then are trapped by the solidifying shell. The present study provides a comprehensive approach to evaluating the life cycle of SEN. [ABSTRACT FROM AUTHOR]

The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement. The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12°C. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review aimed to investigate the accuracy of intraoral scan (IOS) impressions of implant-supported restorations in in vivo studies. Methods: A systematic electronic search and review of studies on the accuracy of IOS implant impressions were conducted to analyze the peer-reviewed literature published between 1989 and August 2023. The bias analysis was performed by two reviewers. Data on the study characteristics, accuracy outcomes, and related variables were extracted. A meta-analysis of randomized control trials was performed to investigate the impact of IOS on peri-implant crestal bone loss and the time involved in the impression procedure. Results: Ten in vivo studies were included in this systematic review for final analysis. Six studies investigated the trueness of IOS impressions, but did not reach the same conclusions. One study assessed the precision of IOS impressions for a single implant. Four clinical studies examined the accuracy of IOS implant impressions with a follow-up of 1–2 years. In full arches, IOS impression procedure needed significantly less time than conventional one (mean difference for procedure time was 8.59 min [6.78, 10.40 min], P < 0.001), prosthetic survival rate was 100%, and marginal bone levels of all participants could be stably maintained (mean difference in marginal bone loss at 12 months was 0.03 mm [-0.08, 0.14 mm], P = 0.55). Conclusions: The accuracy of IOS impressions of implant-supported restorations varied greatly depending on the scanning strategy. The trueness and precision of IOS in the partial and complete arches remain unclear and require further assessment. Based on follow-up clinical studies, IOS impressions were accurate in clinical practice. However, these results should be interpreted with caution, as some evidences are obtained from the same research group. [ABSTRACT FROM AUTHOR]

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The present study is designed to explore the relationship between material deprivation and children's life satisfaction, paying particular attention to the mediating mechanisms of bullying victimization by peers and siblings and the moderating mechanisms of indulgent culture. A sample of 15,447 children are drawn from the Wave Three of Children's Worlds: International Survey of Children's Well-being in 14 countries. The results demonstrate that material deprivation negatively influences children's life satisfaction. Furthermore, material deprivation simultaneously enhances children's bullying victimization by peers and siblings, thereby reducing their life satisfaction. Moreover, the effects of material deprivation on bullying victimization by peers, bullying victimization by siblings and life satisfaction are all moderated by indulgent culture, that is, all of these associations are stronger for children who grow up in indulgent culture. This study adds to the current knowledge and provides practical implications for how to promote children's life satisfaction. [ABSTRACT FROM AUTHOR]

Orthopedic applications of Fe have been hindered by the insufficient degradation rate. Alloying with noble elements (such as Ag, Au, and Pt) to generate galvanic couples is a feasible approach. However, the direct preparation of homogenous alloys by mechanical alloying or metallurgy is difficult because of the differences in strength, density, and toughness. In this study, Ag2O was selected as the precursor phase for incorporation into Fe to achieve a homogeneous distribution of Ag, which was then reduced in situ to Ag via a mechanochemical reduction reaction during mechanical alloying. The composite powders were printed as implants by selective laser melting, where a fast cooling rate contributed to the retention of the phase distribution of the obtained powder. The electrochemical tests showed that the Fe-Ag2O implant had a high corrosion current density (21.88 ± 0.12 µA/cm2) and instantaneous corrosion rate (0.23 ± 0.05 mm/year). Moreover, the implant exhibited a faster degradation rate (0.22 mm/year) than Fe (0.15 mm/year) and Fe-Ag (0.21 mm/year) after immersion for 28 d. The acceleration mechanism of the implant could be attributed to the uniformly distributed Ag particles triggering many galvanic couples with the Fe grains, which was confirmed by the observation of the corrosion surface. In addition, the composite implants exhibited good biocompatibility and antibacterial properties. [ABSTRACT FROM AUTHOR]

A novel composite hydrogel (AM/CMC/B) synthesized from peanut shell biochar effectively adsorbs heavy metal Cd in water and reduces its toxicity to tobacco seedlings. The hydrogel, prepared via hydrothermal polymerization using acrylamide (AM), carboxymethyl cellulose (CMC), and peanut shell biochar (B), exhibited a maximum adsorption capacity of 164.83 mg g−1 for Cd2+ and followed a pseudo-second-order kinetic model. In pot experiments, the application of exogenous AM/CMC/B mitigated the inhibitory effects of Cd-contaminated soil on tobacco seedling growth. Addition of 10 mg kg−1 Cd resulted in improved phenotype, root system development, enhanced photosynthetic capacity, stomatal conductance (Gs), stomatal number, and increased antioxidant activity while reducing MDA content and leaf cell death. These findings highlight the potential of AM/CMC/B as an environmentally friendly adsorbent for Cd removal from water and for reducing Cd stress toxicity in tobacco and other plants. [ABSTRACT FROM AUTHOR]

This paper provides both an introduction to and a detailed overview of the principles and practice of classifier calibration. A well-calibrated classifier correctly quantifies the level of uncertainty or confidence associated with its instance-wise predictions. This is essential for critical applications, optimal decision making, cost-sensitive classification, and for some types of context change. Calibration research has a rich history which predates the birth of machine learning as an academic field by decades. However, a recent increase in the interest on calibration has led to new methods and the extension from binary to the multiclass setting. The space of options and issues to consider is large, and navigating it requires the right set of concepts and tools. We provide both introductory material and up-to-date technical details of the main concepts and methods, including proper scoring rules and other evaluation metrics, visualisation approaches, a comprehensive account of post-hoc calibration methods for binary and multiclass classification, and several advanced topics. [ABSTRACT FROM AUTHOR]

The carnivorous gastropod Rapana venosa (Valenciennes, 1846) is one of the most notorious ecological invaders worldwide. Here, we present the first high-quality chromosome-scale reference R. venosa genome obtained via PacBio sequencing, Illumina paired-end sequencing, and high-throughput chromosome conformation capture scaffolding. The assembled genome has a size of 2.30 Gb, with a scaffold N50 length of 64.63 Mb, and is anchored to 35 chromosomes. It contains 29,649 protein-coding genes, 77.22% of which were functionally annotated. Given its high heterozygosity (1.41%) and large proportion of repeat sequences (57.72%), it is one of the most complex genome assemblies. This chromosome-level genome assembly of R. venosa is an important resource for understanding molluscan evolutionary adaption and provides a genetic basis for its biological invasion control. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence can cause critical problems in many applications. To effectively avoid or mitigate turbulence, knowledge of turbulence strength at various distances could be of immense value. Due to light-matter interaction, optical beams can probe longitudinal turbulence changes. Unfortunately, previous approaches tended to be limited to relatively short distances or large transceivers. Here, we explore turbulence probing utilizing multiple sequentially transmitted longitudinally structured beams. Each beam is composed of Bessel-Gaussian ( BG l = 0 , k z ) modes with different k z values such that a distance-varying beam width is produced, which results in a distance- and turbulence-dependent modal coupling to l {{\relax \special {t4ht̂3)}\o:mathrel: {\unhbox \voidb@x \special {t4ht@+{38}{35}x2260;}x}}} 0 orders. Our simulation shows that this approach has relatively uniform and low errors (<0.3 dB) over a 10-km path with up to 30-dB turbulence-structure-constant variation. We experimentally demonstrate this approach for two emulated turbulence regions (~15-dB variation) with <0.8-dB errors. Compared to previous techniques, our approach can potentially probe longer distances or require smaller transceivers. Knowledge of atmospheric turbulence strength at various distances is critical for the development of effective solutions for turbulence mitigation. Here, authors demonstrate how to probe the distribution of turbulence strength along a propagation path with multiple longitudinally structured optical beams [ABSTRACT FROM AUTHOR]

Pelican optimization algorithm (POA) is a new heuristic algorithm that simulates the pelican's natural behavior in the hunting process. In order to improve the convergence speed and accuracy of the original algorithm and to solve the problem that the original algorithm is easy to fall into local optimization, an improved POA based on chaotic interference factor and elementary mathematical function is proposed. In this paper, ten different chaotic interference factors are introduced in the exploration stage of POA. After selecting an improved POA with the best performance, six different elementary mathematical functions are introduced in the exploitation stage of POA to improve its optimization performance. Then 30 benchmark functions in CEC-BC-2017 were used to test the performance of different improved algorithms. The experimental results showed that the performance of the improved algorithms have been improved effectively compared with the original POA, and the accuracy and optimization ability to balance exploration and exploitation were significantly improved. Compared with seven different algorithms, the feasibility of the improved POA proposed in this paper is proved. Finally, four engineering design problems are optimized, and the simulation results show that among four different engineering design problems, the improved POA proposed in this paper is obviously superior to the original POA, which proves that the improved POA based on chaotic interference factor and elementary function is competitive in optimization performance on function optimization and practical engineering applications. [ABSTRACT FROM AUTHOR]

Underwater sound-absorbing structure is vital to the stealth performance of underwater vehicles, specifically to avoid the detection by active sonar. A new composite acoustic structure is proposed in this work, and the impact of structural parameters on sound-absorbing performance are studied by the means of numerical simulation; results show two absorption peaks of 0.75 and 0.95 at 3 kHz and 7 kHz due to the mechanisms of viscous loss and resonance. Subsequently, the optimization strategy of combining response surface method with quantum genetic algorithm is employed to optimize the structure, and results exhibit more superior absorption property with an increase of 6.3% compared with that for original structure. It also shows better efficiency and accuracy in comparison with the optimization strategies in COMSOL software. The optimized composite structure is manufactured and its absorption coefficients are measured and results show an error of 8.1% between experiment and numerical simulation. [ABSTRACT FROM AUTHOR]

The field of computer vision has been applied in many topics and scenes, especially in the shipping business which occupies a large position in the world trade. With the development of ship intellectualization, the task of detection, tracking, segmentation and classification of interested targets become more and more important. Publicly available dataset is the foundation to promote research in shipping. Based on this intention, we systematically present a review of maritime datasets on maritime perception. In this paper, comparison is made in terms of data type, environment, ground authenticity, and applicable research directions. The aim of writing this paper is to help researchers quickly identify the most suitable dataset for their work. [ABSTRACT FROM AUTHOR]

In most data mining tasks, feature selection (FS) is a necessary preprocessing step that can reduce the dimensionality of the dataset while ensuring adequate classification accuracy. In this paper, a ReliefF-guided novel binary equilibrium optimizer (RG-NBEO) is proposed for feature selection. Based on the binary equilibrium optimizer, two novel mechanisms are employed to improve the evolution performance. First, two novel transfer functions (SSr and VVr) based on the concept of opposition learning are proposed to transform the continuous search space into a binary search space and achieve a good balance between exploration and exploitation. Second, a ReliefF bootstrapping strategy is proposed to add and remove features directionally in the iterative process according to the feature weights. The simulation experiments are first based on the equilibrium optimizer (EO) variants constructed from the classical S- and V-shaped transfer functions. The variant EO with the best performance is selected and compared with five superior swarm intelligence optimization algorithms and six classical filter feature selection algorithms. The performance of the proposed method was tested on 18 standard datasets, and the results of the different algorithms were statistically evaluated using the Wilcoxon rank sum test and the Freidman rank sum test. The results show that this method can effectively improve the classification accuracy in most cases. [ABSTRACT FROM AUTHOR]

Shape control of mesoporous carbon microparticles (MCMPs) is of critical importance; in particular, asymmetric shapes that can yield unique properties have attracted significant attention. However, the tailored synthesis of asymmetric MCMPs with ordered structures remains challenging. Herein, we report a facile route to prepare asymmetric MCMPs by neutral interface-guided 3D-confined self-assembly (3D-CSA) of block copolymer/homopolymer (BCP/hP) blends, followed by a self-templated selective direct carbonization strategy. BCP/hP Janus microparticles with ordered hierarchical mesostructures were prepared with emulsion solvent evaporation-induced 3D-CSA. The continuous phase of BCP domains was then crosslinked. Composite asymmetric MCMPs are successfully generated after selective carbonization of the crosslinked continuous phase. This method allows tuning the shape of MCMPs easily by varying the blending ratio of BCP/hP. The composite asymmetric MCMPs combine the advantages of asymmetric shape, ordered structure, high specific surface area, chemical inertness and thermal stability and could provide great possibilities for applications in catalysis, drug delivery, energy conversion and storage. [ABSTRACT FROM AUTHOR]

Several groups of bacteria have complex life cycles involving cellular differentiation and multicellular structures. For example, actinobacteria of the genus Streptomyces form multicellular vegetative hyphae, aerial hyphae, and spores. However, similar life cycles have not yet been described for archaea. Here, we show that several haloarchaea of the family Halobacteriaceae display a life cycle resembling that of Streptomyces bacteria. Strain YIM 93972 (isolated from a salt marsh) undergoes cellular differentiation into mycelia and spores. Other closely related strains are also able to form mycelia, and comparative genomic analyses point to gene signatures (apparent gain or loss of certain genes) that are shared by members of this clade within the Halobacteriaceae. Genomic, transcriptomic and proteomic analyses of non-differentiating mutants suggest that a Cdc48-family ATPase might be involved in cellular differentiation in strain YIM 93972. Additionally, a gene encoding a putative oligopeptide transporter from YIM 93972 can restore the ability to form hyphae in a Streptomyces coelicolor mutant that carries a deletion in a homologous gene cluster (bldKA-bldKE), suggesting functional equivalence. We propose strain YIM 93972 as representative of a new species in a new genus within the family Halobacteriaceae, for which the name Actinoarchaeum halophilum gen. nov., sp. nov. is herewith proposed. Our demonstration of a complex life cycle in a group of haloarchaea adds a new dimension to our understanding of the biological diversity and environmental adaptation of archaea. Bacteria of the genus Streptomyces have complex life cycles involving cellular differentiation and multicellular structures that have never been observed in archaea. Here, the authors show that several halophilic archaea display a life cycle resembling that of Streptomyces bacteria, undergoing cellular differentiation into mycelia and spores. [ABSTRACT FROM AUTHOR]

SPHERE is a large multidisciplinary project to research and develop a sensor network to facilitate home healthcare by activity monitoring, specifically towards activities of daily living. It aims to use the latest technologies in low powered sensors, internet of things, machine learning and automated decision making to provide benefits to patients and clinicians. This dataset comprises data collected from a SPHERE sensor network deployment during a set of experiments conducted in the 'SPHERE House' in Bristol, UK, during 2016, including video tracking, accelerometer and environmental sensor data obtained by volunteers undertaking both scripted and non-scripted activities of daily living in a domestic residence. Trained annotators provided ground-truth labels annotating posture, ambulation, activity and location. This dataset is a valuable resource both within and outside the machine learning community, particularly in developing and evaluating algorithms for identifying activities of daily living from multi-modal sensor data in real-world environments. A subset of this dataset was released as a machine learning competition in association with the European Conference on Machine Learning (ECML-PKDD 2016). [ABSTRACT FROM AUTHOR]

Wire and arc additive manufacturing (WAAM) has attracted more attention because of its advantages in efficiency and cost. The inclination angle and the aspect ratio of the bead deeply affect the overlapping quality and the deposition efficiency in the WAAM. This paper presents a hybrid magnetic field and deposited manufacturing (HMDM) to obtain the ideal bead morphology regulating the morphology parameters. The stirring mechanism of the longitudinal magnetic field on the molten pool and the weld bead offset mechanism is analyzed. Then the multi-level comparative tests were carried out to explore the influence of excitation parameters on the weld bead profile. The factors include magnetic excitation current and distance. The bead profile parameters include width, height, inclination angle, the center of gravity position, and the vertex position. The actual experimental results show that the auxiliary longitudinal magnetic field can change the bead morphology, which has a significant effect on the overlapping and stacking process in additive manufacturing. The auxiliary longitudinal magnetic field provided a novel path to control the weld bead morphology in the wire and arc additive manufacturing, which is positive to promote the development of WAAM effectively. [ABSTRACT FROM AUTHOR]

Self-dual MDS and NMDS codes over finite fields are linear codes with significant combinatorial and cryptographic applications. In this paper, firstly, we investigate the duality properties of generalized twisted Reed-Solomon (abbreviated GTRS) codes in some special cases. Then, a new systematic approach is proposed to obtain Hermitian self-dual (+)-GTRS codes, and furthermore, necessary and sufficient conditions for a (+)-GTRS code to be Hermitian self-dual are presented. Finally, several classes of Hermitian self-dual MDS and NMDS codes are constructed with this method. [ABSTRACT FROM AUTHOR]

We report a high-throughput approach to generating lanthanide-doped upconversion nanoparticle (UCNP) arrays through polymer pen lithography (PPL), where instead of the expensive block co-polymer, two types of polymers are employed with one working as ink carrier, e.g., polyethylene glycol-400 (PEG-400) to facilitate smooth transfer from the tip to the substrate and the other, e.g., polyvinyl pyrrolidone (PVP), as chelator to ensure successful patterning of metal ions. The strong coordination of PVP with rare earth ions (RE3+) is the key for weakening the interaction between RE3+ ions and the carrier PEG-400 so that the good mobility of ink can be retained. Further experimental results have shown that besides PVP, small molecules with functional groups that can coordinate with RE3+ ions, such as oleic acid, can also serve the same role as PVP, which greatly enriches the ink library for PPL. Over 1 cm2 area arrays comprising individual UCNP can be reliably generated with characteristic upconversion luminescence. This strategy not only allows reliable production of individual UCNP arrays, it also paves new avenue to the precise synthesis of multifunctional NPs for lasing, imaging, encryption, and anticounterfeiting. [ABSTRACT FROM AUTHOR]

The constant emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants indicates the evolution and adaptation of the virus. Enhanced innate immune evasion through increased expression of viral antagonist proteins, including ORF9b, contributes to the improved transmission of the Alpha variant; hence, more attention should be paid to these viral proteins. ORF9b is an accessory protein that suppresses innate immunity via a monomer conformation by binding to Tom70. Here, we solved the dimeric structure of SARS-CoV-2 ORF9b with a long hydrophobic tunnel containing a lipid molecule that is crucial for the dimeric conformation and determined the specific lipid ligands as monoglycerides by conducting a liquid chromatography with tandem mass spectrometry analysis, suggesting an important role in the viral life cycle. Notably, a long intertwined loop accessible for host factor binding was observed in the structure. Eight phosphorylated residues in ORF9b were identified, and residues S50 and S53 were found to contribute to the stabilization of dimeric ORF9b. Additionally, we proposed a model of multifunctional ORF9b with a distinct conformation, suggesting that ORF9b is a fold-switching protein, while both lipids and phosphorylation contribute to the switching. Specifically, the ORF9b monomer interacts with Tom70 to suppress the innate immune response, whereas the ORF9b dimer binds to the membrane involving mature virion assembly. Our results provide a better understanding of the multiple functions of ORF9b. [ABSTRACT FROM AUTHOR]

The use of optical interconnects has burgeoned as a promising technology that can address the limits of data transfer for future high-performance silicon chips. Recent pushes to enhance optical communication have focused on developing wavelength-division multiplexing technology, and new dimensions of data transfer will be paramount to fulfill the ever-growing need for speed. Here we demonstrate an integrated multi-dimensional communication scheme that combines wavelength- and mode- multiplexing on a silicon photonic circuit. Using foundry-compatible photonic inverse design and spectrally flattened microcombs, we demonstrate a 1.12-Tb/s natively error-free data transmission throughout a silicon nanophotonic waveguide. Furthermore, we implement inverse-designed surface-normal couplers to enable multimode optical transmission between separate silicon chips throughout a multimode-matched fibre. All the inverse-designed devices comply with the process design rules for standard silicon photonic foundries. Our approach is inherently scalable to a multiplicative enhancement over the state of the art silicon photonic transmitters. The authors demonstrate a multi-dimensional communication scheme that combines wavelength- and mode- multiplexing on photonic integrated circuits using foundry-compatible photonic inverse design and spectrally flattened microcombs [ABSTRACT FROM AUTHOR]

Due to its absorption properties in atmosphere, the mid-infrared (mid-IR) region has gained interest for its potential to provide high data capacity in free-space optical (FSO) communications. Here, we experimentally demonstrate wavelength-division-multiplexing (WDM) and mode-division-multiplexing (MDM) in a ~0.5 m mid-IR FSO link. We multiplex three ~3.4 μm wavelengths (3.396 μm, 3.397 μm, and 3.398 μm) on a single polarization, with each wavelength carrying two orbital-angular-momentum (OAM) beams. As each beam carries 50-Gbit/s quadrature-phase-shift-keying data, a total capacity of 300 Gbit/s is achieved. The WDM channels are generated and detected in the near-IR (C-band). They are converted to mid-IR and converted back to C-band through the difference frequency generation nonlinear processes. We estimate that the system penalties at a bit error rate near the forward error correction threshold include the following: (i) the wavelength conversions induce ~2 dB optical signal-to-noise ratio (OSNR) penalty, (ii) WDM induces ~1 dB OSNR penalty, and (iii) MDM induces ~0.5 dB OSNR penalty. These results show the potential of using multiplexing to achieve a ~30X increase in data capacity for a mid-IR FSO link. A 300-Gbit/s free-space optical communication system is demonstrated in the mid-IR wavelength region by using both wavelength- and mode-division multiplexing. [ABSTRACT FROM AUTHOR]

Influenza infection continues are a persistent threat to public health. The identification and characterization of human broadly neutralizing antibodies can facilitate the development of antibody drugs and the design of universal influenza vaccines. Here, we present structural information for the human antibody PN-SIA28's heterosubtypic binding of hemagglutinin (HA) from circulating and emerging potential influenza A viruses (IAVs). Aside from group 1 and 2 conventional IAV HAs, PN-SIA28 also inhibits membrane fusion mediated by bat-origin H17 and H18 HAs. Crystallographic analyses of Fab alone or in complex with H1, H14, and H18 HA proteins reveal that PN-SIA28 binds to a highly conserved epitope in the fusion domain of different HAs, with the same CDRHs but different CDRLs for different HAs tested, distinguishing it from other structurally characterized anti-stem antibodies. The binding characteristics of PN-SIA28 provides information to support the design of increasingly potent engineered antibodies, antiviral drugs, and/or universal influenza vaccines. Influenza continues to represent a major threat to public health, and the development of monoclonal antibodies (mAbs) that provide broad protection remains a key avenue for therapeutic development. Here, the authors demonstrate the molecular basis of neutralization for a human bnAb (PN-SIA28) against both endemic influenza A and emerging pathogens such as bat H17 and H18 viruses. [ABSTRACT FROM AUTHOR]

The work proposes an efficient quadratic hexahedral solid element for size-dependent static and dynamic analyses of porous multi-directional functionally graded materials within the modified couple stress elasticity. The new element is constructed by following the process of the penalty unsymmetric finite element method in which the C1 continuity is enforced in weak sense. Furthermore, the independent rotation is introduced to approximate the continuum rotation and enhance the C0 continuous isoparametric interpolation for determining the test functions. In contrast, the trial functions are formulated based on the metric stress functions and the weighted residual method. Several benchmark tests involved with shell structures of different geometric forms and material distributions are evaluated, and the numerical results demonstrate that the new element can capture the size effect of porous multi-directional FG shells accurately. The findings also reveal that, as the material length scale parameter (MLSP) grows, the bending behavior is locked up gradually so that the out-plane vibration modes become more and more difficult to excite than in-plane vibration modes. Thus, not only the natural frequency but also the order of modes can be controlled by MLSP. [ABSTRACT FROM AUTHOR]

Introduction: Cataract extraction could improve visual acuity (VA) for patients with retinitis pigmentosa (RP), while the surgery may increase photoreceptor degeneration through light damage. In this study, we conducted a systematic review and meta-analysis to investigate the effectiveness and prediction of VA after cataract surgery in patients with RP. Methods: We comprehensively extracted data from literature of available studies with quality control processing. Improvement of VA before and after cataract surgery of different durations of follow-up and different structural integrity of the preoperative macular ellipsoid zone (EZ) in patients with RP were compared. VA was measured by the logarithm of the minimum angle of resolution (logMAR). Results: Sixteen studies were subjected to analysis. Postoperative VA was significantly improved versus preoperative, with a mean difference (MD) of 0.57 [95% confidence interval (CI) 0.45, 0.69], and a fixed-effect model was applied during follow-up durations of 1 day to 1 month (I2 = 0%). Similarly, for follow-up durations of 1–3 months, 3–6 months, and 6–12 months, postoperative VAs were all better than preoperative values, with MDs of 0.36 (95% CI 0.31, 0.41), 0.35 (95% CI 0.23, 0.46), and 0.22 (95% CI 0.14, 0.30) (I2 < 50%). For follow-up duration of 1–5 years, the random-effect model was applied for higher heterogeneity (I2 = 81%), with an MD of 0.26 (95% CI 0.09, 0.43). There was no significant difference in the improvement of the EZ-invisible group, with an MD of 0.27 (95% CI − 0.17, 0.70) (I2 = 82%). There were significant differences between EZ-abnormal and EZ-normal groups in preoperative and postoperative VA, with MDs of 0.56 (95% CI 0.27, 0.85) and 0.46 (95% CI 0.27, 0.65) (I2 > 50%). Conclusions: Cataract surgery could improve VA for patients with RP during long-term follow-up, and the surgery is not recommended for patients with invisible preoperative macular EZ. However, further studies are required to address the problem of excessive light exposure to the degenerated retina in patients with RP with the cataract removed. The study protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022340165). [ABSTRACT FROM AUTHOR]

The theoretical predictions and experimental synthesis of H3S and LaH10 superconductors with record high superconducting transition temperatures (Tc) have promoted the hydrogen-based superconducors to be a research hotspot in the field of solid-state physics. Here, we predict an unprecedented layered structure CaH15, with high Tc of 189 K at 200 GPa using ab initio calculations. As concerns the novel structure, one layer is made of a hydrogen nonagon, the other layer consists of a Ca atom and six H2 molecular units surrounding the Ca atom. This layered structure was also found in SrH15, YH15, and LaH15 at high pressures, each materials exhibit high Tc especially YH15 can reach above 200 K at 220 GPa. It represents the second class of layered superhydrides with high value of Tc after pentagraphene like HfH10. [ABSTRACT FROM AUTHOR]

Owing to the scarcity of land resources, commitment to sustainable land use is particularly critical to human development and environmental protection. As a characteristic and powerful means for China to deal with the excessive expansion and inefficient use of construction land, construction land reduction (CLR) is performing a significant role in the economic, ecological and social sustainability of land use. Nevertheless, being a product of the new policy, CLR has inevitably encountered multiple barriers in meeting multifaceted sustainability requirements. In order to holistically recognize and effectively manage interactive CLR barriers with limited management resources from a time dimension, this study designs an integrated approach based on qualitative research methods, multi-criteria decision-making and strategic planning matrix for tackling the identification, evaluation and planning of CLR barriers, respectively. From an empirical study of Shanghai's CLR practice, 18 CLR barriers are summarized with their direct and indirect impacts on sustainability assessed. Based on their overall impacts and planning periods, the 18 barriers are categorized into four strategic planning zones corresponding to different types of strategies in a strategic planning matrix. Results indicate that seven barriers (deficient regulations and policies, ineffective implementation of existing regulations and policies, inadequate incentive mechanism, limited funding, contradiction of benefit distribution, incomplete information disclosure, and lack of support from subjects involved) are grouped into the priority zone where all the required resources should be allocated with the highest priority, with three (internal conflicts at all levels of governments, lack of sustainability awareness, and lack of available experience) placed into the long-term zone, requiring a sustained investment of appropriately scaled resources. Research outcomes can provide support for policy makers and practitioners to allocate their resources and efforts to better manage and overcome these CLR barriers for sustainable land use. [ABSTRACT FROM AUTHOR]

Background: The present study aims to investigate whether malnutrition defined by the Global Leadership Initiative in Malnutrition (GLIM) criteria using hand-grip strength (HGS) adequately predict postoperative complications and long-term survival in patients underwent radical gastrectomy for gastric cancer in a similar manner to GLIM-defined malnutrition using skeletal muscle index (SMI).Methods: Patients who underwent radical gastrectomy for gastric cancer from August 2014 to June 2019 were included in this study. Clinical data were prospectively collected. Malnutrition was diagnosed based on the two-step approach following the GLIM criteria. Skeletal muscle mass was assessed using SMI based on abdominal computed tomography (CT) scans, or assessed using HGS.Results: A total of 1359 patients were included in this study, in which 36.2% of the patients were at risk of malnutrition (Nutritional Risk Screening 2002 scores ≥3). The incidence of malnutrition was 28.2% and 27.5% using SMI and HGS, respectively. There was a high agreement between the two criteria of malnutrition (kappa = 0.863, P < 0.001). Both of the two criteria of malnutrition were independently associated with postoperative complications (SMI-GLIM, P = 0.041; HGS-GLIM, P = 0.023), overall survival (P < 0.001, both), and disease-free survival (P < 0.001, both), with similar odds ratio or hazard ratio after adjusting for the same confounding variables. HGS-GLIM malnutrition (P = 0.046) but not SMI-GLIM malnutrition (P = 0.270) was associated with a higher incidence of severe complications.Conclusions: GLIM criteria using HGS is a useful tool to diagnose malnutrition and has a similar or even better predictive value for postoperative complications and long-term survival after radical gastrectomy for gastric cancer compared with GLIM criteria using SMI. [ABSTRACT FROM AUTHOR]

Omicron SARS-CoV-2 is rapidly spreading worldwide. To delineate the impact of emerging mutations on spike's properties, we performed systematic structural analyses on apo Omicron spike and its complexes with human ACE2 or S309 neutralizing antibody (NAb) by cryo-EM. The Omicron spike preferentially adopts the one-RBD-up conformation both before and after ACE2 binding, which is in sharp contrast to the orchestrated conformational changes to create more up-RBDs upon ACE2 binding as observed in the prototype and other four variants of concern (VOCs). Furthermore, we found that S371L, S373P and S375F substitutions enhance the stability of the one-RBD-up conformation to prevent exposing more up-RBDs triggered by ACE2 binding. The increased stability of the one-RBD-up conformation restricts the accessibility of S304 NAb, which targets a cryptic epitope in the closed conformation, thus facilitating the immune evasion by Omicron. These results expand our understanding of Omicron spike's conformation, receptor binding and antibody evasion mechanism. The SARS-CoV-2 Omicron variant spreads rapidly. Here the authors show that Omicron S preferentially adopts the one-RBD-up conformation, which leads to a non-RBM-binding monoclonal antibody escape. Mutagenesis reveals that S371L, S373P and S375F substitutions enhance the conformational stability. [ABSTRACT FROM AUTHOR]

The channel capacity of terahertz (THz) wireless communications can be increased by multiplexing multiple orthogonal data-carrying orbital-angular-momentum (OAM) beams. In THz links using OAM multiplexing (e.g., Laguerre-Gaussian LG ℓ , p beams with p = 0), the system performance might degrade due to limited receiver aperture size and multipath effects. A limited-size aperture can truncate the received beam profile along the radial direction. In addition, due to beam divergence, part of the beam might interact with reflectors in the environment, causing the signal to reflect and interfere at the receiver with the directly propagating part of the beam; this is known as the multipath effect. In this paper, we simulate and analyze the impact of both effects on the equality of the THz OAM link by considering a full two-dimensional (2-D) LG modal set. The simulation results show (i) a limited-size receiver aperture can induce power loss and modal power coupling mainly to LG modes with the same ℓ but p > 0 for directly propagated OAM beams; (ii) the multipath effect can induce modal power coupling across multiple 2-D LG modes, which leads to inter-channel coupling among the different channels in an OAM multiplexed link; (iii) the interference between the reflected and direct beams can induce intra-channel coupling between the received signals from the reflected and direct beams; and (iv) beams with a higher OAM order (e.g., from ± 1 to ± 5) or a lower carrier frequency (e.g., from 0.1 to 1 THz) experience larger intra- and inter-channel coupling. The intra- and inter-channel coupling in an OAM-multiplexed THz link can degrade the signal-to-noise ratio (SNR) and induce SNR penalty when compared to a single-channel system. [ABSTRACT FROM AUTHOR]

One of the main objectives of quantum error-correction theory is to construct quantum codes with optimal parameters and properties. In this paper, we propose a class of 2-generator quasi-cyclic codes and study their applications in the construction of quantum codes over small fields. Firstly, some sufficient conditions for these 2-generator quasi-cyclic codes to be dual-containing concerning Hermitian inner product are determined. Then, we utilize these Hermitian dual-containing quasi-cyclic codes to produce quantum codes via the famous Hermitian construction. Moreover, we present a lower bound on the minimum distance of these quasi-cyclic codes, which is helpful to construct quantum codes with larger lengths and dimensions. As the computational results, many new quantum codes that exceed the quantum Gilbert-Varshamov bound are constructed over F q , where q is 2, 3, 4, 5. In particular, 16 binary quantum codes raise the lower bound on the minimum distance in Grassl’s table (Grassl in bounds on the minimum distance of linear codes and quantum codes. ). In nonbinary cases, many quantum codes are new or have better parameters than those in the literature. [ABSTRACT FROM AUTHOR]

The influence of doping on the high-Tc superconductor Im-3 m-H3S has attracted great attention since the addition of the external elements is expected to further increase the Tc value or lower the stable pressure of H3S. Here, we systematically investigated the electronic structures and superconductive properties of H6SX (X = N, P, As, O, Se, F, Cl, and Br) through first-principle calculations at 200 GPa. Only H6SP, H6SSe, and H6SBr are dynamically stable and the Tc of H6SSe can reach 182 K. The bonding analysis shows that stronger covalent interactions are beneficial for higher Tc values for these ternary metallic covalent superconductors. The improvement of Tc in doped H3S systems could be obtained through introducing stronger covalent interactions and light atomic massive. In addition, we found that the replacement of Br atoms can reduce the stable pressure of H3S to 150 GPa with Tc about 159–174 K. [ABSTRACT FROM AUTHOR]

Investigation of the low-temperature (LT) selective catalytic reduction (SCR) of NOx has adsorbed extensive efforts, and is now a hot topic in environmental catalysis. In this work, we cautiously explore the mechanism beneath LT-SCR via a combination of chemical-trapping methods, using BaO/Al2O3 as a NOx-intermediate trap, temperature-programmed desorption (TPD) and in situ FTIR spectroscopy over a series of metal-oxide catalysts. Our results show a linear correlation between LT-SCR rates and amounts of nitrites generated from NO oxidative activation and sequentially stored on BaO/Al2O3, implying key roles of nitrites/nitrite-precursors in LT-SCR. [ABSTRACT FROM AUTHOR]

To address the problems of coarse columnar grains, inhomogeneous microstructure, and anisotropic mechanical properties of Ti-6Al-4V manufactured by wire and arc additive manufacturing (WAAM) and hybrid additive manufacturing with plasma-arc deposition, synchronous microrolling (HDMR) was examined in this study. HDMR leads to significant grain refinement and isotropy improvement. Unrolled additive manufacturing alloys show typical columnar grains, while the microrolled ones show a transition from columnar to equiaxed grains with the fraction depending on the microrolling force. The microrolling-induced formation of equiaxed grains is caused by both dendrite fragmentation and prior β recrystallization in the subsequent deposition. Interestingly, the rolling force required for good grain refinement in HDMR is much lower than that in WAAM with subsequent cold rolling. Microstructure characteristics are present near the grain boundaries due to the recrystallized α lamellae distribution. The width of the basketweave α lamellae decreases with the increasing microrolling force. The yield strength and ultimate tensile strength of HDMR samples increase with a decrease in elongation anisotropy. This study shows that HDMR can effectively refine grains and improve the tensile properties of titanium alloys, providing a broad prospect for the rapid formation of large titanium alloy parts. [ABSTRACT FROM AUTHOR]

Four subsurface flow constructed wetlands (SFCWs) filled with different substrates including ceramsite, ceramsite+pyrite, ceramsite+ferrous sulfide, and ceramsite+pyrite+ferrous sulfide (labeled as SFCW-S1, SFCW-S2, SFCW-S3, and SFCW-S4) were constructed, and the removal of nitrogen and phosphorus by these SFCWs coupled with intermittent aeration in the front section was discussed. The key findings from different substrate analyses, including nitrification and denitrification rate, enzyme activity, microbial community structure, and the X-ray diffraction, revealed the nitrogen and phosphorus removal mechanism. The results showed that the nitrogen and phosphorus removal efficiency for SFCW-S1 always remained the lowest, and the phosphorus removal efficiency for SFCW-S4 was recorded as the highest one. However, after controlling the dissolved oxygen by intermittent aeration in the front section of SFCWs, the nitrogen and phosphorus removal efficiencies of SFCWs-S2 and S4 became higher than those of SFCW-S1, and SFCW-S3. It was noticed that the pollutants were removed mainly in the front section of the SFCWs. Both precipitation and adsorption on the substrate were the main mechanisms for phosphorus removal. A minute difference of nitrification rate and ammonia monooxygenase activity was observed in the SFCWs' aeration zone. The denitrification rates, nitrate reductase, nitrite reductase, and electron transport system activity for SFCW-S2 and SFCW-S4 were higher than those detected for SFCW-S1 and SFCW-S3 in the non-aerated zone. Proteobacteria was the largest phyla found in the SFCWs. Moreover, Thiobacillus occupied a large proportion found in SFCW-S2, and SFCW-S4, and it played a crucial role in pyrite-driven autotrophic denitrification. [ABSTRACT FROM AUTHOR]

In free-space optical communications that use both amplitude and phase data modulation (for example, in quadrature amplitude modulation (QAM)), the data are typically recovered by mixing a Gaussian local oscillator with a received Gaussian data beam. However, atmospheric turbulence can induce power coupling from the transmitted Gaussian mode to higher-order modes, resulting in a significantly degraded mixing efficiency and system performance. Here, we use a pilot-assisted self-coherent detection approach to overcome this problem. Specifically, we transmit both a Gaussian data beam and a frequency-offset Gaussian pilot tone beam such that both beams experience similar turbulence and modal coupling. Subsequently, a photodetector mixes all corresponding pairs of the beams' modes. During mixing, a conjugate of the turbulence-induced modal coupling is generated and compensates the modal coupling experienced by the data, and thus the corresponding modes of the pilot and data mix efficiently. We demonstrate a 12 Gbit s−1 16-QAM polarization-multiplexed free-space optical link that is resistant to turbulence. A transmission scheme for free-space optical communications is shown to be highly robust against turbulence. [ABSTRACT FROM AUTHOR]

Apatite-rich rocks from marine phosphorites, alkaline igneous complexes, and iron-oxide copper gold (IOCG) deposits commonly contain elevated but sub-economic contents of rare earth elements (REE). In this study, we selected fluorapatite from the Paleoproterozoic Yinachang IOCG deposit in Southwest China to evaluate the mechanisms of REE remobilization, transportation and precipitation during fluorapatite alteration. Four texturally and compositionally distinct types of fluorapatite were identified. Ap1, related to mantle-derived magmatic-hydrothermal fluid from dolerite intrusions, contains the highest (REE + Y) content (> 1 wt%). Ap2 was directly deposited from a magmatic-hydrothermal fluid related to Cu mineralization, rich in Cl and S but poor in REE + Y. Pervasive REE-rich mineral inclusions and micro-pores in the altered domains from Ap1 and Ap3-1 indicate that extensive metasomatic alteration occurred via a coupled dissolution-reprecipitation process, which was related to a late oxidizing hydrothermal fluid. After the end of the dissolution-reprecipitation process, Ap3-2 formed through regrowth of Ap3-1. Ap4 in late monazite-sulfide veins has extremely high positive Eu anomalies (24–32) and the highest Eu contents, which are related to a late reduced hydrothermal fluid. This study demonstrates that the geochemical and textural features of altered fluorapatite from the Yinachang IOCG deposit were controlled by both a sorption processes and the oxidation states of the hydrothermal fluids. The most salient feature in the Yinachang deposit is that REE remobilization associated with the alteration of fluorapatite by Neoproterozoic hydrothermal fluids is not strictly localized in extent, and REE in fluorapatite can also be transported in distance and precipitate as REE-rich minerals in independent mineralized veins. [ABSTRACT FROM AUTHOR]