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In this work, a new type of graphene ICs only comprising multiple graphene field-effect transistor (GFET) components is first reported. Based on the GFET design that enables homogeneous electrical characteristics in batch-made devices, the practicality and functionality significances of multi-GFET integration are experimentally demonstrated via high-fidelity amplifiers for baseband analog signals. Different from the quadratic relationship of the gate-controlled current output (in saturation region) in the traditional silicon-based MOSFETs, the saturation current output of GFETs relating to the gate-controls possesses high linearity. This advantage overcomes the inherent nonlinear distortion issues in the existing silicon MOSFET amplifiers and potentially provides a promising scenario for the accurate preamplification of weak analog signals. Besides, the novel circuit configuration and signaling principle may expand the developmental paradigm of analog amplifiers and set groundwork for the development and practicalization of advanced carbon-based nanoelectronic ICs. [ABSTRACT FROM AUTHOR]

The Lufeng Sag and Huizhou Sag, both located in the Zhu-1 Depression, have similar geographical locations, but their reservoir characteristics in the Paleogene Wenchang Formation show obvious differences. Primary intergranular pores are mainly developed in the Lufeng Sag. However, secondary pores are the main reservoir space in the Huizhou depression. Overall, the reservoir properties of the Lufeng Sag are better than those of the Huizhou Sag. To analyse the differences between the Paleogene reservoirs in these two areas, this study mainly uses assay data, such as rock thin sections, scanning electron microscope images, drilling, and logging, to analyse the differential development mechanisms of high-quality reservoirs, and two types of reservoir development models were concluded. The results show that the anti-compaction primary porosity preservation mode is mainly developed in the Lufeng Sag. High compositional maturity quartz sandstone is the congenital condition of primary porosity development. The top and bottom calcareous cementation formed of the large set of thick sand bodies increases the rock's anti-compaction ability. The early shallow burial slows down the compaction action of overlying strata. Under the low geothermal temperature, it can delay the time for deep reservoirs to enter the middle diagenetic stage. The reservoirs in the Huizhou Sag are developed with the secondary dissolution pore development model. The Wenchang Formation reservoir in the Huizhou Sag has a large area of contact with source rocks, and organic acids can migrate to sandstone reservoirs for dissolution. Additionally, the secondary dissolution pores are more developed because the Wenchang Formation reservoirs in the Huizhou Sag contain more easily dissolved substances. [ABSTRACT FROM AUTHOR]

The simple preparation of SiC/C nanocomposites for efficient microwave absorption is a significant and challenging issue. In this work, an atmospheric thermal plasma was used to achieve the one-step, continuous, and controllable synthesis of SiC/C nanocomposites via hexamethyldisilane decomposition. The microstructure, phase composition, elemental composition, and microwave absorption performance of the SiC/C nanocomposites were investigated. The results indicated that the as-prepared SiC/C nanocomposites were a mixture of C-coated β-SiC nanoparticles with an average size of 11–16 nm and free carbon layers with the layer number of 1–6. The ratio of SiC to carbon layers could be tuned by adjusting the arc current, hydrogen/carbon contents. It was also found that the SiC/C nanocomposites with high carbon content exhibited good microwave absorption, and the optimal reflection loss approached −60.6 dB at 7.39 GHz. The microwave absorption mechanism indicated that the presence of carbon layers in the SiC/C nanocomposites improved the polarization and conduction loss, which was closely associated with the enhanced microwave absorption. These results afford a novel strategy for designing and synthesizing SiC/C nanocomposites with strong microwave absorption. [ABSTRACT FROM AUTHOR]

For large-scale and sustainable water electrolysis, it is of great significance to develop cheap and efficient electrocatalysts that can replace platinum. Currently, it is difficult for most catalysts to combine high activity and stability. To solve this problem, we use cobalt to regulate the electronic structure of ruthenium to achieve high activity, and use carbon matrix to protect alloy nanoparticles to achieve high stability. Herein, based on the zeolitic imidazolate frameworks (ZIFs), a novel hybrid composed of RuCo alloy nano-particles and N-doped carbon was prepared via a facile pyrolysis-displacement-sintering strategy. Due to the unique porous structure and multi-component synergy, the optimal RuCo500@NC750 material in both acidic and alkaline media exhibited eminent HER catalytic activity. Notably, the 3-RuCo500@NC750 obtained a current density of 10 mA cm−2 at 22 mV and 31 mV in 0.5 M H2SO4 and 1.0 M KOH, respectively, comparable to that of the reference Pt/C catalyst. Furthermore, the Tafel slopes of the catalyst are 52 mV Dec−1 and 47 mV Dec−1, respectively, under acid and alkali conditions, and the catalyst has good stability, indicating that it has broad application prospects in practical electrolytic systems. This work contributes to understanding the role of carbon-supported polymetallic alloy in the electrocatalytic hydrogen evolution process, and provides some inspiration for the development of a high efficiency hydrogen evolution catalyst. [ABSTRACT FROM AUTHOR]

A novel viscosity probe (NV1) was developed for assessing cancer cell migration. NV1 can respond to changes of viscosity rapidly and exhibits high sensitivity in HepG2 cells treated with starvation, rotenone and nystatin. Importantly, NV1 was used for the first time to evaluate the relationship between intracellular viscosity changes and cancer cell migration and proved that increased intracellular viscosity inhibits cell migration while decreased intracellular viscosity promotes cell migration. [ABSTRACT FROM AUTHOR]

We report the magneto-transport measurements on bulk HfTe5 with carrier mobility exceeding 100 000 cm2/(V s). The longitudinal resistance anomaly and the sign change in Hall coefficient with temperature are observed, which may be induced by Lifshitz transition. When the magnetic field is applied along the b-axis and a-axis at low temperature, a series of Shubnikov–de Haas oscillations on the longitudinal transport exhibit, demonstrating a three-dimensional Fermi-surface pocket for HfTe5 rather than two-dimensional (2D). The investigations on Landau level fan diagram confirm the existence of the non-trivial π Berry phase. The cyclotron mass m cyc as around 0.02 m e and quantum scattering time τ at about 1.76 ps are also estimated with Lifshitz–Kosevich theory. Further detailed analysis suggests that a stacked quantum Hall effect attributed to multi-parallel 2D conduction layers develops in HfTe5. [ABSTRACT FROM AUTHOR]

This article proposed a harmonic suppression scheme that used a dc-dc converter as an active harmonic injector to cancel voltage harmonics on the HVdc bus within a hybrid power generation centre (HPGC). A permanent magnet synchronous generator and a battery are considered to supply power to a common HVdc bus through their dedicated ac-dc and dc-dc converters respectively within the HPGC. We proposed simplified mathematical models of harmonics from the ac-dc and dc-dc converters. Thereafter, an active power sharing scheme between the PMSG and the battery is developed to control the magnitudes of targeted harmonics to be the same. The targeted harmonics on the HVdc bus can thus be cancelled by properly tuning the carrier signal phase angles within ac-dc and dc-dc converters. A closed-loop control scheme has been developed and this scheme is with no extra hardware cost. To demonstrate the effectiveness of the proposed scheme, we selected the first-band harmonic (fc − 3f0) as the targeted harmonic component. The harmonic cancellation scheme for this component has been developed and validated using experimental results. It has been demonstrated that the proposed method can achieve over 90% reduction of this specific harmonic component on the HVdc bus within this HPGC using one dc-dc converter. [ABSTRACT FROM AUTHOR]

The signal of spaceborne low-frequency full-polarization synthetic aperture radar (full-pol SAR) contains abundant ionospheric information. Phased Array L-band Synthetic Aperture Radar (PALSAR) working in the L-band has been verified as an emerging ionospheric sounding technology. Aiming for a future P-band SAR system, this paper investigates the ability of the P-band SAR system in ionospheric one-dimensional and two-dimensional detection. First, considering different systematic error levels, the total electron content (TEC) retrieval in L/P-band is studied by using three typical full-pol SAR data sets based on a circular polarization algorithm. Second, the TEC data retrieved by SAR are fused with the ionosonde, and the joint retrieval of ionospheric electron density is performed. Results show that the P-band TEC retrieval is approximately twice as accurate as the L-band retrieval under the same conditions, and possesses excellent robustness. In addition, the TEC obtained by L/P-band SAR can be used to correct the electron density of the topside on the ionosonde. Results also show that compared with the topside correction accuracy of L-band SAR, that of the P-band SAR is improved by more than 20%. SAR has natural high-resolution characteristics and the P-band signal contains more obvious ionospheric information than the L-band signal. Therefore, future spaceborne P-band SAR has many advantages in two-dimensional fine ionospheric observation and one-dimensional electron density retrieval. [ABSTRACT FROM AUTHOR]

The portable air purifier can't uniformly remove the PM2.5 at each personnel position in a room, which causes the unevenness of PM2.5 distribution. In order to achieve priority purification of PM2.5 at the personnel position, experiments and simulations were conducted here to determine the time required for the purifier to reduce the PM2.5 concentration in a room to 15 μg/m3 (hereafter referred to as the purification time) in each area of the room at different wind speeds. SPSS was used to conduct regression analysis of the simulated data and determine the contribution rate of each impact factor, and assess the prediction model for the purification time. This prediction model can be used to calculate the purification time of any location in rooms of different sizes. The results show that, there was a nonlinear relationship between the purification time and impact factors, however, when the purifier wind speed is determined, PM2.5 purification time shows a linear relationship with the remaining impact factors. The contribution rate of the initial PM2.5 concentration to the purification time was largest. Increasing the wind speed will further increase the contribution rate of the initial PM2.5 concentration, but reduce the contribution rate of the air supply angle, personnel distance, and personnel angle. [ABSTRACT FROM AUTHOR]

Objective To investigate what social, psychological, personality, and behavioral factors affect overtime heart rate changes of college students. Participants: The daily heart rates of over 600 undergraduates at the University of Notre Dame were unobtrusively recorded via Fitbit devices from August 16, 2015, to May 13, 2017. Method: Latent Growth-Curve modeling strategy is utilized to examine how daily mean heart rate and its standard deviation change over time, and what foregoing factors predict observed changes. Results: The mean heart rate increased and its standard deviation stayed the same over the 637 days. Heart rate levels go up with that of social contacts, an indicator of peer influence. Both daily heart rate levels and changes are also affected by multiple external factors. Conclusion: Human heart rate is not only a physiological phenomenon but also a social-psychological one, as it is systematically affected by peer networks, social contexts, and human activities. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prevalence of gestational diabetes mellitus (GDM) and its determinants among pregnant women in the Tongzhou district of Beijing, China.Methods: This study was performed on data collected in the routine work of the prenatal health care system from 27,119 pregnant women in the Tongzhou district of Beijing during 2013-2018. Univariate and multivariate logistic regression analyses were used to assess the factors associated with GDM.Results: The overall prevalence of GDM was 24.24%, and it showed an increasing trend over the 6 years. A univariate analysis showed that the prevalence of GDM increased with age (p < .001). In multivariate analysis, it was found that women with a non-local household registration, as well as those without a local household registration but whose husbands had one, had a lower risk for GDM than both spouses who had local registration. Women who were overweight/obese had a higher risk for GDM than women with a normal pre-pregnancy body mass index. Multipara women had a lower likelihood of developing GDM.Conclusions: We found a slightly higher prevalence of GDM in the Tongzhou district of Beijing than has been found in other studies, and the prevalence rose over the 6 years of the study. Advanced age, pre-pregnancy overweight or obesity, and local household registration were important risk factors for GDM. Multiparity may be a protective factor against developing GDM. Intensive health education on related determinants should be strengthened for the prevention and control of GDM, especially in high-risk women. [ABSTRACT FROM AUTHOR]

Mas related G-protein-coupled receptor member X2 (MrgX2) has been identified as the crucial receptor in drug induced pseudo-allergic reactions and allergic diseases. In this research, the first type of fluorescent agonists (ZX1, ZX2 and ZX3) for MrgX2 were developed by conjugating environment-sensitive fluorophore coumarin to MrgX2 selective agonists (R)-ZINC-3573. Their environment-sensitive property was confirmed by the dramatically increase of fluorescent intensity after binding to the hydrophobic ligand binding domain MrgX2, which help to overcome the high background signal. Based on these characteristics, they can be used for selective visualization of MrgX2 in living cells even with their own background interference. Among these fluorescent agonists, compound ZX2 possessed splendid spectroscopic properties, outstanding pharmacological activities (EC 50 = 0.93 μM, K D = 1.97 μM). And a competitive binding assay was established with ZX2 to analysis the binding affinity of MrgX2 agonists, which shown high coherence with the results of cell membrane chromatography. To our knowledge, these probes are the first fluorescent ligands of MrgX2 with agonistic activity and environment-sensitive property, which is expected to use for the development of MrgX2 molecular pharmacology and serve as a convenient high-throughput screening tool for the drug candidates targeting MrgX2. • A series of coumarin fluorescent agonists for MrgX2 were synthesized. • Their fluorescent intensity increased dramatically after binding to MrgX2. • They can be used for selective visualization of MrgX2 in living cells. • ZX2 possessed splendid spectroscopic properties and binding activity among them. • A competitive binding assay was established to analysis MrgX2 agonists. [ABSTRACT FROM AUTHOR]

Objective: To explore the feasibility and clinical efficacy of a modified medial collateral ligament indentation technique in total knee arthroplasty (TKA) with severe type II valgus deformity. Methods: Consecutive patients with Krackow type II valgus deformity >20° who underwent a primary unilateral TKA between May 2008 and June 2017 were studied retrospectively. A medial collateral ligament indentation technique was performed in 20 patients (MCLI group), and 23 patients received the routine lateral structures release technique (LSR group). Radiological parameters, such as the valgus angle (VA), and functional outcomes including the use of constraint implants, Knee Society Score (KSS), Knee Society Function score (KSF), and thickness of the polyethylene insert were compared between the two groups. Results: A total of 43 consecutive patients had a minimum 2‐year follow‐up. The preoperative VA was comparable between the MCLI (23.5° ± 5.8°) and LSR groups (21.3° ± 3.2°, P = 0.134), as was the postoperative VA (1.1° ± 2.1° and 2.5° ± 3.0°, respectively, P = 0.084). The mean KSS and KSF scores in the MCLI group were 30.2 ± 4.8 and 38.8 ± 4.8, respectively, before surgery, and they increased to 91.3 ± 2.6 and 86.5 ± 2.4 at the last follow‐up. The scores in the LSR group were 31.5 ± 7.5 and 36.5 ± 7.8 before surgery and 92.4 ± 3.5 and 88.5 ± 3.6 at the last follow‐up. While no statistically significant differences in pre‐ or postoperative functional scores were found between the two groups, the MCLI group had thinner polyethylene inserts (9.5 ± 1.1 mm vs 12.9 ± 1.5 mm) and less use of constrained condylar inserts (15% vs 69.6%). During follow‐up, the MCLI group had fewer complications. Conclusion: A modified MCLI technique can achieve good outcomes in TKA with type II valgus deformity of >20°. It can maintain a normal joint line level, reduce the use of constrained condylar knee prostheses, and is a reliable choice for severe genu valgum. [ABSTRACT FROM AUTHOR]

Metabolic syndrome (MS) has been an important health issue in the world, and insulin resistance (IR) is one of the characteristics of MS, increasing the risk for the onset and poor prognosis of type 2 diabetes mellitus (T2D). However, the interactional effect of obesity or abnormal body composition on the correlation between gut microbiota and IR in T2D patients is not well-explored. This cross-sectional study used a body composition monitor to evaluate lean tissue mass and fat tissue mass. IR was calculated using homeostatic model assessment-insulin resistance (HOMA-IR). Eight pairs of 16S rRNA gene primers specific to Firmicutes, Bacteroidetes, Clostridium leptum group, Faecalibacteriumprausnitzii, B acteroides, Bifidobacterium, Akkermansia muciniphila, and Escherichia coli were utilized to measure their abundance by qPCR. One hundred and fifty-four T2D patients were enrolled and stratified by the median HOMA-IR (2.5) and body mass index (BMI) of 25 kg/m2. A lower abundance of A. muciniphila was found in T2D patients with high HOMA-IR and BMI respectively. HOMA-IR and BMI had a synergistic effect on the reduction of the abundance of A. muciniphila. After adjusting metabolic factors, the low abundance of A. muciniphila significantly increased the risk for greater severity of IR. Furthermore, the negative correlation between A. muciniphila and IR was only found in T2D patients with high lean tissue. In conclusion, decreased abundance of fecal A. muciniphila enhanced the severity of IR in Asians with T2D, especially those having lean mass, and this significant relationship was independent of obesity. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic stability of the monotone decreasing kink profile solitary wave solutions of the generalized Gardner equation with dissipative term. Firstly, we obtain the estimation of the first-order and second-order derivatives for monotone decreasing kink profile solitary wave solutions, then by using anti-derivative strategy, with the help of prior estimate and Young inequality, we overcome the difficulties caused by two higher-order nonlinear terms of the equation in the estimation, and prove the asymptotic stability of monotone decreasing kink profile solitary wave solution in the sense of L ∞ norm. [ABSTRACT FROM AUTHOR]

Hypopharyngeal squamous cell carcinoma (HSCC) is highly malignant and extremely aggressive, making it one of the worst prognoses among all kinds of head and neck squamous cell carcinoma (HNSCC); therefore, gaining insight into molecular mechanisms of HSCC is of profound significance. In the current manuscript, we revealed the elevated expression of long noncoding RNA (lncRNA) LEF1-AS1 in HNSCC which was associated with the poor prognosis by bioinformatic analysis. Moreover, we noticed that LEF1-AS1 dramatically accelerated the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in HSCC cell line FaDu. Most importantly, we illustrated that LEF1-AS1 played as a competitive endogenous RNA (ceRNA) via sponging miR-221-5p and thereby positively regulated gap junction protein alpha 1 (GJA1) expression, thus aggravated tumor progression and EMT. In conclusion, for the first time, we demonstrated lncRNA LEF1-AS1 as a novel biomarker for HNSCC and suggested LEF1-AS1/miR-221-5p/GJA1 axis as promising diagnostic and therapeutic target for HSCC treatment. [ABSTRACT FROM AUTHOR]

Background: The incidence of human papillomavirus (HPV) positive oropharyngeal cancer (OPC) is rising but HPV negative OPC is decreasing in Western countries. In Taiwan, the incidence of HPV negative OPC is common but the incidence of HPV positive OPC remains unknown. The objective of this study is to estimate the incidence trend and the survival of HPV positive OPC in Taiwan.Methods: Between 1999 and 2014, primary tumor tissues from 425 incident OPCs were obtained from 5 medical centers in Taiwan. 408 OPCs were evaluated by the EasyChip HPV genotyping (King-Car, I-Lan, Taiwan) and 369 OPCs by p16 staining. The clinical data were retrospectively obtained from the medical records.Results: In our study, 29% of OPCs were HPV positive. The percentage of HPV positive OPC was stable from 1999 to 2014 (25% (1999-2002), 30% (2003-2006), 30% (2007-2010), 29% (2011-2014)). The estimated crude incidence rate of HPV positive OPC increased significantly from 0.62 (1999-2002), 1.06 (2003-2006), 1.52 (2007-2010) to 1.74 (2011-2014) per 100,000 person-year. The sensitivity and specificity of p16 staining for positive HPV infection were 92% and 91%, respectively. The 5-year overall survival rates for patients with HPV positive OPC and with HPV negative OPC were 67.8% and 49.0%, respectively (HR = 0.52 (0.35-0.76), p = 0.0005). Patients with HPV positive OPC but no betel nut/cigarette exposure had the best overall survival (5-year: 88.2%, p < 0.0001). Patients with HPV negative OPC and betel nut/cigarette exposure had the worst overall survival (5-year: 46.6%, p < 0.0001). Patients with HPV positive OPC but also with betel nut/cigarette exposure had poorer 5-year overall survival (48.3%, p < 0.01).Conclusion: The incidence of HPV positive OPC is increasing along with HPV negative OPC, which leads to stably low percentage of HPV positive OPC in Taiwan. HPV positive OPC may become an important head and neck cancer when the incidence of HPV negative OPC declines in the near future. P16 is a useful surrogate marker for HPV infection in OPC and a good prognostic indicator for treatment outcome of OPC. Patients with HPV positive OPC but no betel nut/cigarette exposure has an excellent prognosis. Betel nut/cigarette exposure significantly worsens the prognosis of HPV positive OPC. [ABSTRACT FROM AUTHOR]

This work presents a palladium-catalyzed oxime ether-directed ortho-selective benzoylation using benzoylformic acid as the acyl source with a palladium catalyst and 4CzIPN as the co-catalyst under light. Various non-symmetric benzophenone derivatives were obtained in moderate to good yields. A preliminary mechanism study revealed that the reaction proceeds through a free radical pathway. [ABSTRACT FROM AUTHOR]

Background: Low syphilis testing uptake is a major public health issue among men who have sex with men (MSM) in many low- and middle-income countries. Syphilis self-testing (SST) may complement and extend facility-based testing. We aimed to evaluate the effectiveness and costs of providing SST on increasing syphilis testing uptake among MSM in China.Methods and Findings: An open-label, parallel 3-arm randomized controlled trial (RCT) was conducted between January 7, 2020 and July 17, 2020. Men who were at least 18 years of age, had condomless anal sex with men in the past year, reported not testing for syphilis in the last 6 months, and had a stable residence with mailing addresses were recruited from 124 cities in 26 Chinese provinces. Using block randomization with blocks of size 12, enrolled participants were randomly assigned (1:1:1) into 3 arms: standard of care arm, standard SST arm, and lottery incentivized SST arm (1 in 10 chance to win US$15 if they had a syphilis test). The primary outcome was the proportion of participants who tested for syphilis during the trial period and confirmed with photo verification and between arm comparisons were estimated with risk differences (RDs). Analyses were performed on a modified intention-to-treat basis: Participants were included in the complete case analysis if they had initiated at least 1 follow-up survey. The Syphilis/HIV Duo rapid test kit was used. A total of 451 men were enrolled. In total, 136 (90·7%, 136/150) in the standard of care arm, 142 (94·0%, 142/151) in the standard of SST arm, and 137 (91·3%, 137/150) in the lottery incentivized SST arm were included in the final analysis. The proportion of men who had at least 1 syphilis test during the trial period was 63.4% (95% confidence interval [CI]: 55.5% to 71.3%, p = 0.001) in the standard SST arm, 65.7% (95% CI: 57.7% to 73.6%, p = 0.0002) in the lottery incentivized SST arm, and 14.7% (95% CI: 8.8% to 20.7%, p < 0.001) in the standard of care arm. The estimated RD between the standard SST and standard of care arm was 48.7% (95% CI: 37.8% to 58.4%, p < 0.001). The majority (78.5%, 95% CI: 72.7% to 84.4%, p < 0.001) of syphilis self-testers reported never testing for syphilis. The cost per person tested was US$26.55 for standard SST, US$28.09 for the lottery incentivized SST, and US$66.19 for the standard of care. No study-related adverse events were reported during the study duration. Limitation was that the impact of the Coronavirus Disease 2019 (COVID-19) restrictions may have accentuated demand for decentralized testing.Conclusions: Compared to standard of care, providing SST significantly increased the proportion of MSM testing for syphilis in China and was cheaper (per person tested).Trial Registration: Chinese Clinical Trial Registry: ChiCTR1900022409. [ABSTRACT FROM AUTHOR]

In this paper, a novel 3-dimensional (3D) non-stationary geometry-based stochastic model (GBSM) is proposed to mimic the ship-to-ship multiple-input multiple-output (MIMO) communication channels. To reflect the realistic maritime propagation environment, the effects of rough sea surface scattering and evaporation duct propagation are investigated in the proposed channel model. The model considers the movements of transmitter (Tx), receiver (Rx), and scatterers, and is capable of capturing the channel characteristics, including non-stationary characteristics, spatial consistency, location-dependent property, etc. Through taking the array cluster evolution into account, the proposed channel model can describe massive MIMO channels and can easily switch to conventional MIMO channel model by adjusting corresponding parameters. Based on the proposed model, key statistical properties like delay/angular/Doppler power spectrum density (PSD), space-time correlation function (STCF), stationary interval, and root mean square (RMS) Doppler/delay spreads in multi-scenarios are derived. The usefulness and accuracy of the proposed model are demonstrated by comparing theoretical results, simulation results, and corresponding measurement results. [ABSTRACT FROM AUTHOR]

Fitbit wearable devices provide users with objective data on their physical activity and sleep habits. However, little is known about how users develop their usage patterns and the key mechanisms underlying the development of such patterns. In this article, we report results from a longitudinal analysis of Fitbit usage behavior among a sample of college students. Survey and Fitbit data were collected from 692 undergraduates at the University of Notre Dame across two waves. We use a structural equation modeling strategy to examine the relationships among three dimensions of Fitbit usage behavior corresponding to three elements of the habit loop model: trust in the accuracy of Fitbit physical activity and sleep data (cue), intensity of Fitbit device use (routine), and adjustment of physical activity and sleep behaviors based on Fitbit data (reward). More than 75 percent of participants trusted the accuracy of Fitbit data and nearly half of the participants reported they adjusted their physical activities based on the data reported by their devices. Participants who trusted the Fitbit physical activity data also tended to trust the sleep data, and those who intensively used Fitbit devices tended to adjust both their physical activities and then sleep habits. Psychological states and traits such as depression, extroversion, agreeableness, and neuroticism help predict multiple dimensions of Fitbit usage behaviors. However, we find little evidence that trust, Fitbit usage, or perceived adjustment of activity or sleep were associated with actual changes in levels of sleep and activity. We discuss the implications of these findings for understanding when and how this new monitoring technology results in changes in people's behavior. [ABSTRACT FROM AUTHOR]

Gut microbiota plays important roles in host nutrition, metabolism and immunity, and is affected by multiple factors. However, the understandings of the gut microbiota in pigs within different breeds, growth periods and genders from a large cohort remain largely undefined. In the present study, the characteristics of the gut microbiota in 120 pigs of different breeds, growth periods and genders were investigated using the Illumina MiSeq PE300 combined with QIIME2 platform. A total of 7 388 636 raw reads and 16 411 features were obtained. Additionally, the microbial diversity, compositions and phenotypes were described. 66.53% microbiota belonged to the top 10 most abundant genera (pan gut bacteria), and 28 species were commonly identified (core gut bacteria, commonality ≥ 75%) among the pigs. Besides, the correlations within pan and core gut microbiota were firstly investigated. The metagenomic function was predicted by using PICRUSt2. Furthermore, the explanatory effects of the influencing factors suggested that growth period was the greatest contributor to the gut microbiota in pigs. These results expanded our knowledge of mammalian gut microbiota within different influencing factors and microbial‐related biological features in swine, which contributes to improving animal production and assisting animal model research. [ABSTRACT FROM AUTHOR]

A systematic study of heavy metal levels, bioaccessibilities, and gastrointestinal cytotoxicity in two popular consumed vegetables mint (Mentha spicata Linn.) and pea sprouts (Pisum sativum Linn.) from three major producing cities in Yunnan, Southwest China were conducted for evaluating potential health risk to local inhabitants. The mean concentrations of As, Cd, Cr, and Pb were 0.34, 0.06, 1.04, and 0.79 mg/kg, respectively, with Cr and Pb exceeding 1.86–2.63 folds greater than the limit of Chinese National Standards and WHO/FAO. Their average gastric and intestinal bioaccessibilities varied within 12.1–59.4% and 9–53.3%, 0–93.3% and 0–82%, 41.8–71.1% and 19.1–62.9%, 16.1–93.6% and 9.5–81.7%, respectively. Cd in mint was the highest (86.8% and 39%, in the gastric phase and intestinal phase), while Pb had the highest bioaccessibility of 69.9% and 48.7% in pea sprouts. The bioaccessible target hazard quotient (BTHQ) of As, Cr, and Pb from vegetables reflected no potential health risks. However, toxicity assays showed intestinal digesta induced significant cytotoxicity in human intestinal Caco-2 cells, indicating the existing models based on total or bioaccessible heavy metals may be not accurate enough to assess their human health risk, especially for adverse effects evaluation. Taken together, the human risk assessment should be modified by taking their gastrointestinal cytotoxicity into account. [Display omitted] [ABSTRACT FROM AUTHOR]

Resveratrol, a natural antioxidant that maintains better bioactivity under hypoxia, has anti-tumor effects, but its underlying mechanism is controversial and the effect on Triple-negative breast cancer (TNBC) remains unclear. Herein, we investigated the anti-TNBC mechanism of resveratrol under a mimic hypoxic tumor microenvironment and explored a method of combining metformin to improve the therapeutic effect. The results showed an inverted "U" shaped relationship between the cell viability and resveratrol concentrations. Low concentrations of resveratrol (LRes) promoted proliferation and migration in MDA-MB-231 cells by activating JAK3/STAT3 signaling pathway, while high concentrations of resveratrol (HRes) inhibited cell growth and induced both autophagy and apoptosis through MAPK signaling pathway. Meanwhile, HRes treatment resulted in the up-regulation of antioxidant-related genes SOD3 and FAM213B, the increase of catalase activity and NAD(P)H level, which leading to a reducing microenvironment in cells. Notably, metformin could inhibit the proliferation and migration induced by LRes, whereas promote apoptosis induced by HRes. Moreover, metformin enhanced the reducing environment via further increasing the catalase activity and NAD(P)H level. These findings conclude the anti-TNBC mechanism of HRes should be attributed to its antioxidant activity and metformin enhances its reducibility. Metformin combined with resveratrol exerts a synergistic therapeutic effect on TNBC and effectively prevents tumor progression. [Display omitted] • To investigate the anti-TNBC mechanism of resveratrol under a mimic hypoxic tumor microenvironment. • Low concentrations of resveratrol (LRes) promote proliferation and migration in TNBC. • High concentrations of resveratrol (HRes) inhibit cell growth and induce both autophagy and apoptosis. • HRes treatment results in the up-regulation of antioxidant gene SOD3 and FAM213B, and enhances NAD(P)H level. • Metformin can inhibit the proliferation and migration induced by LRes, while enhance the anti-TNBC activity of HRes. [ABSTRACT FROM AUTHOR]

This study investigated the diagnostic accuracy and affecting factors of ultrasound (US)-guided core-needle biopsy (CNB) in patients with treated head and neck squamous cell carcinoma (HNSCC). We retrospectively reviewed patients with treated HNSCC who received US-guided CNB from January 2011 to December 2018 with corresponding imaging. Pathological necrosis and fibrosis of targeted lymph nodes (LNs) were evaluated. We analyzed the correlation between CNB accuracy and clinical and pathological characteristics. In total, 260 patients were included. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CNB for nodal recurrence were 84.47%, 100%, 100%, 54.67%, and 86.92%, respectively. CNB of fibrotic LNs had significantly worse sensitivity, NPV, and accuracy than that of non-fibrotic LNs. Similarly, CNB of necrotic LNs had significantly worse sensitivity, NPV, and accuracy than non-necrotic LNs. Multivariate regression revealed that fibrotic LN was the only independent factor for a true positive rate, whereas both necrotic LN and fibrotic LN were independent factors for a false negative rate. The diagnostic accuracy of CNB in treated HNSCC patients is affected by LN necrosis and fibrosis. Therefore, CNB results, particularly for necrotic or fibrotic LNs, should be interpreted carefully. [ABSTRACT FROM AUTHOR]

The types and adsorption mechanism of ion-exchange fibers are reviewed, and the adsorption effects of ion-exchange fibers modified by different chemical methods to remove heavy metal ions from water are compared. In addition, ion-exchange fibers can also be used in decolorization and desalination of sugar juice. However,the industrial application of ion exchange fiber is not mature enough, such as high price, waste liquid regeneration and other problems, so can not completely replace ion exchange resin and other ion exchange materials. Therefore, in the future large-scale application of ion-exchange fiber, it is necessary to solve its industrial production problem first. [ABSTRACT FROM AUTHOR]

Ionospheric delay is one of the main sources of error in satellite positioning and navigation. Ionospheric broadcast parameters are required to correct for the ionospheric delay, especially in the case of massive single-frequency users. The well-known Klobuchar model has been providing the ionospheric delay corrections for GPS users during the last several decades. For Galileo users, a three-dimensional electron density model (NeQuick G) based on the NeQuick climatological model is used to correct for ionospheric delay. The recently completed Chinese BeiDou Satellite Navigation System (BDS) broadcasts two types of ionospheric models coefficients on different signals. In this article, we propose a simplified worldwide ionospheric model (SWIM) for satellite positioning. By comparison, our SWIM model has better performance than the Klobuchar model in terms of accuracy at both low and high solar activity, and is comparable to the NeQuick G and BDS ionospheric models. At the same time, the SWIM model has high efficiency because of the simple calculation process. It has great potential for ionospheric delay corrections in satellite navigation and positioning. [ABSTRACT FROM AUTHOR]

Here, we report a 41‐year‐old female with type II VUF after hysteromyomectomy.We report the diagnosis of VUF by imaging method, and provide a feasible treatment for this complication after pelvic surgery. [ABSTRACT FROM AUTHOR]

The problem of a spherical cavity expanded from an initial radius to another cavity in finite soil is investigated in this paper. A similarity transformation technique is used to solve the partial differential equations (PDEs) of spherical cavity expansion, which allows the stress, displacement and pore pressure induced by cavity expansion to be captured. The derived analytical solution is validated by comparing the degenerate solution with published results on cavity expansion in an infinite medium. The present analytical method can conveniently capture the effect of the finite boundary. A simple application to compaction grouting confirms its utility in geotechnical practice. [ABSTRACT FROM AUTHOR]

The two types of wind observations, profiler and radar radial velocity, have been successfully assimilated into numerical weather prediction (NWP) systems. However, the added value of profiler data, especially from a densely deployed profiler network, is unknown when assimilated together with Doppler radar radial velocity. In this article, two combined assimilation strategies of profilers along with radar radial winds are compared within a convective-scale data assimilation (DA) framework. In strategy I, the profiler data are assimilated with conventional observations to generate an intermediate analysis that acts as a prior for radar data assimilation. In strategy II, both profiler and radar data are considered as storm-scale and assimilated within the same pass. Single- and dual-observation assimilation experiments indicate that for strategy I, the profiler DA improvement can be partly canceled by the potentially negative impact of the assimilation of single-radar radial velocity afterward, particularly when the radial wind is nearly orthogonal to the prevailing wind. For strategy II, important complements are provided when profilers are assimilated within the same pass along with radial winds. The diagnostics for a low-level jet case demonstrate that both strategies facilitate improved analyses and forecasts. But strategy II may bring more moderate analysis increments, which indicate mutual constraints of the profiler and radial winds when assimilated within the same pass. The results obtained in 1-month, retrospective cycling experiments also show that the strategy II outperforms the strategy I with slightly better wind and precipitation forecasts. Significance Statement: Due to the high spatial–temporal wind information provided by profiler and radar radial velocity measurements, their combined assimilation would be expected to improve wind analysis. To fully utilize dense profiler data and radar radial wind in future operational applications, this study proposes a suitable assimilation strategy. If the profilers are defined as synoptic-scale observations, the profiler and Doppler radar data must be assimilated in different passes to adopt different length and variance scales. Whereas it is more reasonable to use a small background correlation length consistent with the radial velocity and, therefore, assimilate in the same pass if the profiler data are considered to better sample storm-scale features. Single- and dual-observation experiments indicate that profiler data provide important complements, while the assimilation of single-radar radial wind may yield analyzed wind results that do not depict the ground truth. A low-level jet case and a 1-month impact study further show that the combined assimilation strategy of assimilating both profiler and Doppler radar using smaller background correlation lengths enhances the analysis and forecasting of wind, resulting in more accurate accumulated precipitation forecasts. [ABSTRACT FROM AUTHOR]

Functional data analysis offers a set of statistical methods concerned with extracting insights from intrinsically infinite-dimensional data and has attracted considerable amount of attentions in the past few decades. In this paper, we study robust functional linear regression model with a scalar response and a functional predictor in the framework of reproducing kernel Hilbert spaces. A gradient descent algorithm with early stopping is introduced to solve the corresponding empirical risk minimization problem associated with robust loss functions. By appropriately selecting the early stopping rule and the scaling parameter of the robust losses, the convergence of the proposed algorithm is established when the response variable is bounded or satisfies a moment condition. Explicit learning rates with respect to both estimation and prediction error are provided in terms of regularity of the regression function and eigenvalue decay rate of the integral operator induced by the reproducing kernel and covariance function. [ABSTRACT FROM AUTHOR]

Underwater movement of objects can generate hydrodynamic and thermal wakes. Inverting these wake signals can provide information about underwater vehicles, making it essential to understand the characteristics and laws of those hydrodynamic and thermal signals. This study experimentally explored the evolution of vorticity wake of underwater vehicles in a uniform water body and their influence on the infrared characteristics of surface wakes. First, we analyzed the background noise of the water surface flow field and then studied the evolution of the vorticity wake, the coupling relationship between the thermal and hydrodynamic signals of the wake, and the influence of depth and speed on the intensity of the wake signal. The experimental results showed that the water above the vehicle has a strong suppression of vorticity. When the vorticity owes sufficient intensity and duration, the vortical structure is found to be the primary cause of the thermal signal, which destroys the hot skin layer on the water surface. The superposition of waves generated by the ovoid body leads to a non-monotonic variation in the intensity of the wake signal with motion speed. The findings of this study can provide experimental support for infrared detection of underwater vehicles. • The evolution laws of vortex wake generated by underwater vehicle were studied experimentally. • The coupling relationship between the vortex and thermal wake was studied experimentally. • The variation laws of the vortex and thermal wakes with diving depth and speed of ovoid body were investigated. • The impact of wave superposition on wake signals was investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combination of steric control strategy and asymmetric strategy. • Detailed analysis of the effect of steric hindrance on polymerization behavior. • Preparation of ultra-high molecular weight highly branched polyethylene elastomers. • Catalyst design strategy of 'Three Large and One Small' around the metal center. • Prepared polyethylene material showed nearly perfect strain recovery ability. The use of α-diimine nickel catalysts to prepare high molecular weight branched polyethylene has matured, but few work reports consider high branch density and ultrahigh molecular weight. Herein, through a combination of asymmetric and steric control strategies, series of catalysts with a gradual increase number of N -aryl ortho -benzhydryl substituent were prepared. Through the analysis of polymerization results, it is believed that large steric hindrance plays a significant role in improving the catalyst thermal stability and reducing the temperature sensitivity of the product branch density and molecular weight. Surprisingly, Ni4, which has three large benzhydryl groups and one small methyl group at the four sites of the N -aryl ortho -position, has high chain growth rate and strong chain walking ability, allows it to prepare highly branched polyethylene with ultra-high molecular weight at higher temperatures with high activity. Moreover, this type of polyethylene material exhibits excellent strain recovery capabilities (98.2 %). [ABSTRACT FROM AUTHOR]

Open-world instance segmentation has recently gained significant popularity due to its importance in many real-world applications, such as autonomous driving, robot perception, and remote sensing. However, previous methods have either produced unsatisfactory results or relied on complex systems and paradigms. We wonder if there is a simple way to obtain state-of-the-art results. Fortunately, we have identified two observations that help us achieve the best of both worlds: (1) query-based methods demonstrate superiority over dense proposal-based methods in open-world instance segmentation, and (2) learning localization cues is sufficient for open-world instance segmentation. Based on these observations, we propose a simple query-based method named OpenInst for open-world instance segmentation. OpenInst leverages advanced query-based methods like QueryInst and focuses on learning localization cues. Notably, OpenInst is an extremely simple and straightforward framework without any auxiliary modules or post-processing, yet achieves state-of-the-art results on multiple benchmarks. Specifically, in the COCO → UVO scenario, OpenInst achieves a mask Average Recall (AR) of 53.3, outperforming the previous best methods by 2.0 AR with a simpler structure. We hope that OpenInst can serve as a solid baseline for future research in this area. The source codes are available at https://github.com/hustvl/OpenInst. • OpenInst achieves state-of-the-art results on multiple datasets. Our study confirms that incorporating box IoU into query-based detectors improves their generalizability. • OpenInst is the first work that achieves both simplicity and high-performance, serving as a solid baseline for future research in the open-world community. • We conduct extensive ablation studies to analyze each component used in our model. We hope those observations benefit future researches in this area. [ABSTRACT FROM AUTHOR]

Copper as a widely applied element in food supply chain can cause serious contamination issues that threats food safety. In this research, we present a quick and visible method for trace copper ion (Cu2+) quantification in practical food samples. Polymer dots (Pdots) were firstly conjugated with a copper-specific DNA aptamer and then tailored with rhodamine B (RhB) to extinguish the electrochemiluminescence (ECL) signal through a resonance energy transfer process. The selective release of RhB leads to signal restoration when exposed to trace Cu2+ levels, achieving remarkable linearity with the logarithm of Cu2+ concentration within the range of 1 ng/L to 10 μg/L with an impressively low limit of detection at 11.8 pg/L. Most notably, our device was also applicable on visualizing and quantifying trace Cu2+ (∼0.2 μg/g) in practical Glycyrrhiza uralensis Fisch. samples, underscoring its potential as a tool for the early prevention of potential copper contamination in food samples. • A new electrochemiluminescence aptasensors device was developed for Cu2+ detection. • The device can realize rapid and visualized detection of trace Cu2+. • The device can be applied on visualizing and quantifying Cu2+ in practical samples. [ABSTRACT FROM AUTHOR]

Lost circulation presents a complex challenge in drilling operations. Ascribed to the favorable remaining in fracture, strong resistance to efflux, and entire gel block rather than individual particles, the self-healing gels have been broadly applied as lost circulation material (LCM). In this study, we utilized layered bimetallic hydroxide (LDH) as a dynamic crosslinking agent to synthesize a novel nanocomposite (NC) gel through in-situ polymerization following the stripping of LDH in acrylic acid (AA) solution. LDH/PAA NC gels exhibit excellent self-healing properties, rheological strength, mechanical properties and adhesion properties, with these attributes being influenced by the LDH content. At 110 °C, the optimal LDH/PAA NC gel rapidly self-healed in bentonite mud within 1 h, revealing storage modulus (G′) of 4041 Pa, tensile strength of 8.04 kPa, and adhesion strength of 2.1 kPa. Visual plugging tests revealed that the LDH/PAA NC gel could withstand pressures up to 4 MPa, surpassing the capabilities of MA gel, which lacked self-healing properties. These findings highlight the potential of LDH/PAA NC gels as efficient LCM, offering a promising solution for controlling lost circulation during drilling operations. [Display omitted] • The self-healing time of LDH/PAA NC gel at 70 °C is only 3.5 h. • The self-healing properties of LDH/PAA NC gels can be regulated by the amount of LDH added. • The optimal LDH/AA NC gels exhibited higher pressure-bearing capacity than pristine gel. [ABSTRACT FROM AUTHOR]

External wall composite insulation materials have shown great potential for energy saving and emission reduction in the construction industry, but cement-based material as one of the external wall composite insulation materials has the problem of high thermal conductivity. Herein, a composite insulation material was prepared using the press method by expanded polystyrene (EPS) and cement of different calcium silicate content. The addition of porous calcium silicate provides nucleation sites for cement hydration to promote hydration reaction and increase the porosity of the inorganic cementitious phase from 75 % to 85 % and refine the average pore size from 2826.09 nm to 421.31 nm. The cement-based composite insulation material which the calcium silicate content is 20 % has 0.0423 W/(m·K) in the thermal conductivity, which is 23.1 % lower than the non-calcium silicate content of cement-based composite insulation material (0.055 W/(m·K)). The simulation analysis proves that the improved insulating properties are attributed to the increased interface between solid-phase and gas phase, thinner heat transfer walls, and longer heat transfer paths due to the pore structure changes in the inorganic cementitious phase. This proposed composite insulation material provides a new choice for external wall insulation. [ABSTRACT FROM AUTHOR]

The pulsation and jet of underwater explosion bubble heavily affected by the boundary conditions. To explore the pulsation behavior and jet load of underwater explosion bubble near a damaged double structure, some double plates with circular hole were designed. The electric spark-generated bubble was employed to act as the underwater explosion bubble, and the experiment research on bubble pulsation and jet below the double plate with circular hole was carried out. The bubble pulsation and jet process were recorded by a high-speed camera, and the bubble jet load was measured by a wall pressure sensor. The results show that with the growth of the standoff distance, the bubble jet changes from the type I "gas-liquid two-phase jet" to the type II "gas-liquid two-phase jet", and finally into the water jet. The load of the type I "gas-liquid two-phase jet" are characterized with high peak pressure with short duration in the initial pressure stage, and low pressure with long duration in the standing pressure stage. Whereas the type II "gas-liquid two-phase jet" feature high peak pressure with short duration in the initial pressure stage without standing pressure stage. • The difference between the bubble pulsation characteristics near the double plate with a hole and the free field bubble is found and analyzed. • A new bubble load type of "gas-liquid two-phase jet" is found by highspeed camera and wall pressure sensor. • A thorough analysis was conducted on the load characteristic and formation mechanism of "gas-liquid two-phase jet". [ABSTRACT FROM AUTHOR]

Telco players are constantly evaluating their loss in customer revenue or customer churn, especially on the prevention, control, and risk assessment of churn. In this paper, a domain-order based shallow fusion deep learning model, the Fully Connected Layer Convolutional Neural Network - Long Short-Term Memory (FCLCNN-LSTM) is designed and applied to a decision support system to assess the risk of customer churn. First, a majority least absolute shrinkage and selection operator (Maj-LASSO) algorithm is proposed to identify churn predictors that have an important impact on classification. The proposed Maj-LASSO algorithm is different from previous studies that solved the study of unbalanced data and feature selection separately, but solved both as one problem to give the feature selection method under unbalanced data. Then, a fully connected layer based on multiple ReLU neurons is used to balance the importance of the features. Doing so addresses the problem where some key features are overlooked due to their unequal contribution to the risk assessment of telco customer churn. Third, a 2D convolutional neural network based on domain information and an LSTM model based on ordinal information are combined to learn the complex mapping between the features and labels, to improve the accuracy and generalizability of the predictive model. The proposed FCLCNN-LSTM model is different from the previous single spatial model or temporal model, but improves the network classification feature extraction capability from both temporal and spatial dimensions, thus innovatively solving the problem of model development for large-scale and high-dimensional data, and applying it in the field of telecommunication customer churn prediction. Finally, using three public customer churn datasets from the Kaggle and UCI platform, the FCLCNN-LSTM model is compared against other classification models, namely, Logistic Regression, Support Vector Machine, Random Forest, eXtreme Gradient Boosting (XGBoost), Convolutional Neural Network, and Long Short-Term Memory. The experimental results inform that the accuracy of the FCLCNN-LSTM is 3.43% higher than that of the other comparison models, while the AUC is 4.84% higher. Thus, the FCLCNN-LSTM model provides a better decision-making reference for telco players to identify potential churners. [ABSTRACT FROM AUTHOR]

Ambient humidity has an important impact on the performance of flexible electronic devices, and wearable electronic devices will inevitably involve a high humidity environment. To investigate the impact of humidification on flexible phase-change memory, we prepared Sb phase-change film and memory device unit with polyether ether ketone as substrate, and studied the effect of humidification on the properties of the film and device. The results show that the effective transition from an amorphous to a crystalline state can still be achieved by the film after soaking in water for 55 min, and the phase transition temperature increases with the increase of soaking time. Water molecules refine the film grains, resulting in increased crystalline resistance. Sb is a hydrophilic material, and its hydrophilicity decreases after crystallization. The reversible conversion of SET-RESET can be realized under different pulse widths even after the phase change memory device is soaked in water and bent many times. This study shows that antimony-based flexible phase change memory has certain deformation self-healing ability and moisture resistance, which provides a way to expand its application environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Ternary alkali-activated binder was prepared by blast furnace slag (GGBS), recycled powder (RP) and waste glass powder (WGP) using simplex centroid design method. By measuring the fluidity, setting time, drying shrinkage and mechanical property of specimen, the complementary effect of GGBS, RP and WGP was discussed. The reaction mechanism and microstructure were explored by X-ray diffraction and scanning electron microscopy. The results reveal that the addition of RP could significantly reduce the fluidity and setting time of paste, while WGP can obviously improve the rheological property and play a retarding role. The workability of paste can be effectively regulated by mixing RP and WGP together. Whether added alone or in combination, RP and WGP can effectively improve the shrinkage performance. In the ternary system, GGBS can be rapidly activated and form a skeleton structure. The fine RP particles can play a good role in filling the structure, and the pozzolanic reaction of WGP gradually occurs, which makes the microstructure more compact. The incorporation of GGBS, RP and WGP can promote the growth of hydration products, improve the density of microstructure, and form a certain complementary effect. • A ternary solid waste system was designed using simplex centroid design method. • The complementary effect of GGBS, RP and WGP was discussed. • The microstructure and reaction mechanism were analyzed. [ABSTRACT FROM AUTHOR]

The purpose of this work is to optimize the penetration temperature to obtain 316 L honeycomb-filled tube/aluminum matrix composite (HFT/AMC) with good wear resistance. Utilized selective laser melting technology to fabricate honeycomb-filled tubes as reinforcement for the composite material. HFT/AMC was prepared by filling aluminum into honeycomb-filled tubes under three different temperatures of 800 °C, 850 °C, and 900 °C through vacuum infiltration casting. And performed tissue characterization and performance testing. Microstructure, hardness, XRD, and EDS studies showed that the composite materials generate intermetallic compound transition layers of over 100 μm, and the overall strength of the interface was improved. A large number of intermetallic compounds and honeycomb-filled tubes distributed in the aluminum matrix inside the cells jointly strengthen the aluminum-based material. Inspection of worn surfaces of HFT/AMCs revealed abrasive and oxidative wear as the main wear mechanisms. Considering the wear of the produced HFT/AMC under certain conditions, the most suitable infiltration temperature is 850 °C (wear rate: 0.52 ± 0.16 [(mm3/N·m) × 10−3]). This study confirmed that honeycomb-filled tubes can significantly improve the tribological properties of aluminum-based materials. [Display omitted] • HFT/AMCs at different temperatures can achieve good metallurgical bonding. • The IMC layer of HFT/AMC at different temperatures exceeds 100 μm. • The Al matrix hardness of HFT/AMCs at different temperatures is enhanced. • HFT/AMC at different temperatures have excellent tribological properties. • HFT/AMC-stabilized CoF has potential applications in the field of friction materials. [ABSTRACT FROM AUTHOR]

Interface between lattice reinforcement and matrix played a key factor on properties of the lattice reinforced aluminum matrix composites. However, the effect of interface composed of intermetallic compounds on the properties of 316 L lattice/Al composites was still unclear. In this study, 316 L lattice reinforced aluminum composite with continuous interface were prepared by combining laser powder bed fusion (LPBF) and vacuum infiltration, and effect of infiltration temperature on interface evolution and properties of the composite was investigated. Results indicated that a continuous dual-phase interfacial layer consisting of hard intermetallic compounds η-Fe 2 Al 5 and θ-FeAl 3 was formed between the reinforcement and matrix due to diffusion and reaction of iron and aluminum atoms, and the size of needle-type FeAl 3 phase in the interfacial zone increased when infiltration temperature was up from 800 °C to 900 °C. It also confirmed that reinforced by 316 L lattice and hard intermetallic compounds layer, the composite showed excellent mechanical and wear resistant properties, with compressive strength of 657 ± 32 MPa and specific wear rate of 0.20 × 10−3 (mm3/N·m) for the sample prepared at 800 °C, which were over 10 times and one fifth of that of the aluminum matrix individually. This study provides a new strategy for developing 316 L lattice/Al composites with excellent properties. [Display omitted] • LPBF and infiltration are adopted to prepare 316 L lattice/Al composites. • The interface is mainly composed of η-Fe 2 Al 5 and θ-FeAl 3 intermetallic compounds. • High-strength interface greatly contributed to high compressive strength. • Composites show five times increase in the wear resistance of aluminum. [ABSTRACT FROM AUTHOR]

Plastics have long been identified as the main culprit for environmental pollution. Molded pulp products (MPPs) are one of the promising candidates that are made of cellulose fibers by pulping and hot-pressing to replace plastic packaging. However, MPPs generally suffer from insufficient mechanical properties and poor water stabilities due to the intrinsic hydrophilicity of cellulose. This work developed an all biomass-based MPP with excellent mechanical strength and water stability by using lignin as the additive. Lignin was extracted from sugarcane bagasse through Klason and alkaline processes, respectively. The structural differences of lignin, the mechanical properties and water stabilities of lignin-added MPPs were investigated. The results show Klason lignin provides no enhancement in tensile strength due to severe condensation reaction in acid. Alkaline lignin significantly improved the mechanical strength (38 MPa) and Young's modulus (3590 MPa) of MPPs and endowed excellent water stability. The initial water contact angle was measured to be 117° and remained above 50° after 30 min, which was achieved with 20% lignin addition. The water absorption (36%) and thickness swelling ratio (30%) were much lower compared with commercial bagasse tableware. The developed all-biomass composite materials have great potential to replace non-biodegradable plastic packaging materials. [Display omitted] • Lignin obtained from sugarcane bagasse was incorporated to wood pulp. • Molded pulp materials (MPPs) were prepared with good mechanical properties. • Alkaline-lignin-MPPs show a water absorption of 36% and thickness swelling ratio of 30%. • Alkaline-lignin-MPPs show a better biodegradability than commercial bagasse tableware. [ABSTRACT FROM AUTHOR]

Based upon two overlapped, body-unfitted meshes, a type of unified-field monolithic fictitious domain-finite element method (UFMFD-FEM) is developed in this paper for moving interface problems of dynamic fluid-structure interactions (FSI), which is accompanied with high-contrast physical coefficients across the interface and with contacting collisions between the structure and fluidic channel wall in the immersed FSI case. In particular, the proposed novel numerical method consists of a monolithic, stabilized mixed finite element method within the frame of fictitious domain/immersed boundary method (FD/IBM) for generic fluid-structure-contact interaction (FSCI) problems in the Eulerian–updated Lagrangian description, while involving the no-slip type of interface conditions on the fluid-structure interface, and the repulsive contact force/stress on the structural surface when the immersed structure contacts the fluidic channel wall. The developed UFMFD-FEM for FSI/FSCI problems can deal with the structural motion with large rotational and translational displacements and/or large deformation in an accurate and efficient fashion, which is first validated by two benchmark FSI problems and one FSCI model problem, then by experimental results of a realistic FSCI scenario – the microfluidic deterministic lateral displacement (DLD) problem that is applied to isolate circulating tumor cells (CTCs) from blood cells in the blood fluid through a cascaded filter DLD microchip in practice, where a particulate fluid with the pillar obstacles effect in the fluidic channel, i.e., the effects of fluid-structure interaction and structure collision, play significant roles to sort particles (cells) of different sizes with tilted pillar arrays. The developed unified-field, monolithic fictitious domain-based mixed finite element method can be seamlessly extended to more sophisticated, high dimensional FSCI problems with contacting collisions between the moving elastic structure and fluidic channel wall. • A fluid-structure-contact interaction (FSCI) model involving the interaction and collision effects is developed. • A mixed FEM in the monolithic fictitious domain frame is developed with respect to a unified variable pair of velocity and pressure. • Advanced algorithms are designed to handle structural collision, nonlinear system and interpolation between fictitious fluid and structure. • Numerical approaches are validated by benchmark problems, self- and physically designed DLD problems. • Numerical simulations carried out by the developed UFMFD-FEM can help to optimize the design of DLD microchips. [ABSTRACT FROM AUTHOR]

Microenvironment regulation of M‐N4 single‐atom catalysts (SACs) is a promising way to tune their catalytic properties toward the electrochemical CO2 reduction reaction. However, strategies that can effectively introduce functional groups around the M‐N4 sites through strong covalent bonding and under mild reaction conditions are highly desired. Taking the hydrophilic Ni‐N4 SAC as a representative, we report herein a [2+1] cycloaddition reaction between Ni‐N4 and in situ generated difluorocarbene (F2C:), and enable the surface fluorocarbonation of Ni‐N4, resulting in the formation of a super‐hydrophobic Ni‐N4‐CF2 catalyst. Meanwhile, the mild reaction conditions allow Ni‐N4‐CF2 to inherit both the electronic and structural configuration of the Ni‐N4 sites from Ni‐N4. Enhanced electrochemical CO2‐to‐CO Faradaic efficiency above 98 % is achieved in a wide operating potential window from −0.7 V to −1.3 V over Ni‐N4‐CF2. In situ spectroelectrochemical studies reveal that a highly hydrophobic microenvironment formed by the −CF2− group repels asymmetric H‐bonded water at the electrified interface, inhibiting the hydrogen evolution reaction and promoting CO production. This work highlights the advantages of [2+1] cycloaddition reactions on the covalent modification of N‐doped carbon‐supported catalysts. [ABSTRACT FROM AUTHOR]

Microenvironment regulation of M‐N4 single‐atom catalysts (SACs) is a promising way to tune their catalytic properties toward the electrochemical CO2 reduction reaction. However, strategies that can effectively introduce functional groups around the M‐N4 sites through strong covalent bonding and under mild reaction conditions are highly desired. Taking the hydrophilic Ni‐N4 SAC as a representative, we report herein a [2+1] cycloaddition reaction between Ni‐N4 and in situ generated difluorocarbene (F2C:), and enable the surface fluorocarbonation of Ni‐N4, resulting in the formation of a super‐hydrophobic Ni‐N4‐CF2 catalyst. Meanwhile, the mild reaction conditions allow Ni‐N4‐CF2 to inherit both the electronic and structural configuration of the Ni‐N4 sites from Ni‐N4. Enhanced electrochemical CO2‐to‐CO Faradaic efficiency above 98 % is achieved in a wide operating potential window from −0.7 V to −1.3 V over Ni‐N4‐CF2. In situ spectroelectrochemical studies reveal that a highly hydrophobic microenvironment formed by the −CF2− group repels asymmetric H‐bonded water at the electrified interface, inhibiting the hydrogen evolution reaction and promoting CO production. This work highlights the advantages of [2+1] cycloaddition reactions on the covalent modification of N‐doped carbon‐supported catalysts. [ABSTRACT FROM AUTHOR]

Purpose: An investigation was conducted into the impact of various process parameters on the surface and subsurface quality of glass-ceramic materials, as well as the mechanism of material removal and crack formation, through the use of ultrasonic-assisted grinding. Design/methodology/approach: A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. A series of simulations and experiments were conducted to investigate the impact of process parameters on crack depth, surface roughness, and surface topography during ultrasonic-assisted surface and axial grinding. Additionally, the mechanism of crack formation was explored. Findings: During ultrasonic-assisted grinding, the average grinding forces are between 0.4–1.0 N, which is much smaller than that of ordinary grinding (1.0–3.5 N). In surface grinding, the maximum surface stresses between the workpiece and the tool gradually decrease with the tool speed. The surface stresses of the workpiece increase with the grinding depth, and the depth of subsurface cracks increases with the grinding depth. With the increase of the axial grinding speed, the subsurface damage depth increases. The roughness increases from 0.780um/1.433um. Originality/value: A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. The deformation involved in the grinding process is large, and the FEM-SPH modeling method is used to solve the problem that the results of the traditional finite element method are not convergent and the calculation efficiency is low. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of biomass-derived furan compounds provides a green and sustainable approach to produce value-added fuels and chemicals. Despite the achievements in unimolecular transformation, C–C coupling which holds great promise to yield precursors for high-density fuels has not received extensive attention. Herein, we report a Cu2O-derived nanowire array material with switchable selectivity to electrocatalytic reduction of furfural depending on the electrolyte pH. Besides a high selectivity of 98.4% to furfuryl alcohol via hydrogenation at pH 9.5, the Cu2O-derived array structure also exhibits a high selectivity of 83.5% to hydrofuroin via C–C coupling at pH 14. Upon control experiments and detailed characterization of the electrodes, the array architecture is proposed to decrease the diffusion of ketyl radicals which are the key intermediates for C–C coupling. The confined diffusion results in a high local concentration of the radicals in the array and facilitates their collision for enhancing the formation of hydrofuroin. [ABSTRACT FROM AUTHOR]