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Minimally invasive donor hepatectomy is an emerging surgical technique in living donor liver transplantation (LDLT). We examined outcomes across open, laparoscopic, and robotic LDLT using a prospective registry. We analyzed 3448 cases (1724 donor-recipient pairs) from January 2011 to March 2023 (NCT06062706). Among donors, 520 (30%) were female. Adult-to-adult LDLT comprised 1061 (62%) cases. A total of 646 (37%) of the donors underwent open, 165 (10%) laparoscopic, and 913 (53%) robotic hepatectomies. Primary outcomes: donor overall morbidity was 4% (35/903) for robotic, 8% (13/165) laparoscopic, and 16% (106/646) open (P< .001) procedures. Pediatric and adult recipient mortality was similar among the 3 donor hepatectomy approaches: robotic 1.5% and 7.0%, compared with 2.3% and 8.3% laparoscopic, and 1.6% and 5.5% for open donor surgery, respectively (P =.802, P =.564). Secondary outcomes: pediatric and adult recipients major morbidity after robotic hepatectomy was 15% and 23%, compared with 25% and 44% for laparoscopic surgery and 19% and 31% for open surgery, respectively (P =.033, P <.001). Graft and recipient 5-year survival were 90% and 93% for pediatrics and 79% and 80% for adults, respectively. In conclusion, robotic LDLT was associated with superior outcomes when compared with the laparoscopic and open approaches. Both donors and, for the first time reported, recipients benefitted from lower morbidity rates in robotic surgery, emphasizing its potential for further advancing this field.

To discover new osteoclast-targeting antiosteoporosis agents, we identified forty-six diselenyl maleimides, which were efficiently prepared using a novel, simple, and metal-free method at room temperature in a short reaction time. Among them, 3kshowed the most marked inhibition of osteoclast differentiation with an IC50value of 0.36 ± 0.03 μM. Moreover, 3ksignificantly suppressed RANKL-induced osteoclast formation, bone resorption, and osteoclast-specific genes expression in vitro. Mechanistic studies revealed that 3kremarkably blocked the RANKL-induced mitogen-activated protein kinase (MAPK) and NF-κB signaling pathways. In ovariectomized mice, intragastric administration of 3ksignificantly alleviated bone loss, exhibiting an effect similar to that of alendronate. Surface plasmon resonance assay and microscale thermophoresis assay results suggested that RANKL might be a potential molecular target for 3k. Collectively, the findings presented above provided a novel candidate for further development of bone antiresorptive drugs that target RANKL.

The refractory luminal androgen receptor (LAR) subtype of triple-negative breast cancer (TNBC) patients is challenged by significant resistance to neoadjuvant chemotherapy and increased immunosuppression. Regarding the distinct upregulation of glutathione (GSH) and glutathione peroxidase 4 (GPX4) in LAR TNBC tumors, we herein designed a GSH-depleting phospholipid derivative (BPP) and propose a BPP-based nanotherapeutics of RSL-3 (GDNS), aiming to deplete intracellular GSH and repress GPX4 activity, thereby potentiating ferroptosis for treating LAR-subtype TNBC. GDNS treatment drastically downregulated the expression of GSH and GPX4, resulting in a 33.88-fold enhancement of lipid peroxidation and significant relief of immunosuppression in the 4T1 TNBC model. Moreover, GDNS and its combination with antibody against programed cell death protein 1 (antiPD-1) retarded tumor growth and produced 2.83-fold prolongation of survival in the LAR-positive TNBC model. Therefore, the GSH-disrupting GDNS represents an encouraging strategy to potentiate ferroptosis for treating refractory LAR-subtype TNBC.

The vast majority of research on organic photovoltaics (OPVs) has focused on improving device efficiency and stability and reducing material costs. However, if one could refurbish OPVs, their stability might not be so demanding, and the reuse of valuable OPV components can reduce the price per watt of solar modules. Herein, we present a dismantling procedure for reusing the active-layer materials without causing performance losses and for recovering the silver electrode and indium tin oxide (ITO)-electrode substrate via chemical and physical processes. Combined with the developed physical mixing methodology, the OPVs fabricated from recycled components also show comparable performance to that of fresh devices. The potential economic analysis points out that this recycling protocol can save 14.24 $ m−2in industrial scenarios, strongly demonstrating the possibility of recycling OPVs. This work represents a significant step toward cost-effective, high-yield recycling of waste OPVs while also demonstrating the prospects of no material supply constraints for OPV manufacturing shortly.

Focused on the newly secreted tumorous exosomes during melanoma immunotherapy, this work has pioneered an ultra-sensitive spatiotemporal-specific exosome detection strategy, leveraging advanced exosomal membrane engineering techniques. The proposed strategy harnesses the power of amplified lanthanide luminescence signals on these exosomes, enabling precise and real-time monitoring of the efficacy of melanoma immunotherapy. The methodology comprises two pivotal steps. Initially, Ac4ManNAz-associated metabolic labeling is employed to evolve azide groups onto the membranes of newly secreted exosomes with remarkable selectivity. These azide groups serve as versatile clickable artificial tags, enabling the precise identification of melanoma exosomes emerging during immunotherapy. Subsequently, lanthanide-nanoparticle-functionalized polymer chains are controllably grafted onto the exosome surfaces through click chemistry and in situ Fenton–RAFT polymerization, serving as robust signal amplifiers. When integrated with time-resolved fluorescence detection, this strategy yields detection signals with an exceptionally high signal-to-noise ratio, enabling ultra-sensitive detection of PD-L1 antigen expression levels on the spatiotemporal-specific exosomes. The detection strategy boasts a wide linear concentration range spanning from 1.7 × 104to 1.7 × 109particles/mL, with a remarkable theoretical detection limit of 1.28 × 103particles/mL. The remarkable enhancements in detection sensitivity and accuracy facilitate the evaluation of the efficacy of immunotherapeutic interventions in the mouse B16 melanoma model, notably revealing a substantial disparity in PD-L1 levels between immunotherapy-treated and untreated groups (P< 0.01) and further emphasizing the cumulative therapeutic effect that intensifies with repeated treatments (P< 0.001).

A C1-symmetric hexapole helicene (HH) and a C3-symmetric dodecapole helicene (DH) were prepared, and their three-dimensional structures were verified by X-ray crystallography and density functional theory calculations. The molecular geometries and local helical configurations of their most stable diastereomers were correctly predicted by arranging suitable conformations of the peripheral aryl rings. Importantly, the outermost three [5]helicenes with a consistent configuration in DH were observed to increase the thermostability, enantiomerization barrier (ΔH⧧= 40.5 kcal/mol), specific rotation ([α]24D= −4228°) and absorption dissymmetry factor (gabs= 1.35 × 10–3at 453 nm).

The proportion of intense tropical cyclones is expected to increase in a changing climate. However, there is currently no consistent and comprehensive assessment of infectious disease risk following tropical cyclone exposure across countries and over decades. We aimed to explore the tropical cyclone-associated hospitalisation risks and burden for cause-specific infectious diseases on a multi-country scale.

The integration of phase change materials (PCMs) with planar multilayer structures, metasurfaces, waveguides, and photonic integrated circuits has triggered a technological revolution in nonvolatile tunable nanophotonic devices. The performance of devices is largely determined by PCMs, which is highly desired to have a high optical contrast and switchable capability. Here, we present a novel material platform based on Ge0.9 Sb0.1 Te suitable for nanophotonics applications across the entire visible spectral region. Ge0.9 Sb0.1 Te exhibits an optical contrast of up to 66%, significantly higher than that of the most widely reported Ge2Sb2Te5 (30%~35%) and GeTe (45%~50%). Through experiments and first-principles calculations, we reveal that this excellent performance originates from the unique solid-solution structure of crystalline Ge0.9 Sb0.1 Te, which combines high structural order with a narrow optical band gap. Using ultrafast laser induction technology, we demonstrate that the crystalline state of Ge0.9 Sb0.1 Te can be arbitrarily written and erased, achieving 16 distinct optical levels, which exceeds the 7 levels of Ge2Sb2Te5. In addition, we demonstrated grayscale lithography based on Ge0.9 Sb0.1 Te, proving that Ge0.9 Sb0.1 Te has a broad range of application potential as a visible reconfigurable nanophotonic platform.

Exposure to floods might increase the risks of adverse birth outcomes. However, the current evidence is scarce, inconsistent, and has knowledge gaps. This study aims to estimate the associations of flood exposure before and during pregnancy with adverse birth outcomes and to identify susceptible exposure windows and effect modifiers.

Hydroquinone(HQ) is a widely used industrial raw material and is a topical lightening product found in over-the-counter products. However, inappropriate exposure to HQ can pose certain health hazards. This study aims to explore the mechanisms of DNA damage and cell apoptosis caused by HQ, with a focus on whether HQ activates the nuclear factor-κB (NF-κB) pathway to participate in this process and to investigate the correlation between the NF-κB pathway activation and poly(ADP-ribose) polymerase 1(PARP1). Through various experimental techniques, such as DNA damage detection, cell apoptosis assessment, cell survival rate analysis, immunofluorescence, and nuclear-cytoplasmic separation, the cytotoxic effects of HQ were verified, and the activation of the NF-κB pathway was observed. Simultaneously, the relationship between the NF-κB pathway and PARP1 was verified by shRNA interference experiments. The results showed that HQ could significantly activate the NF-κB pathway, leading to a decreased cell survival rate, increased DNA damage, and cell apoptosis. Inhibiting the NF-κB pathway could significantly reduce HQ-induced DNA damage and cell apoptosis and restore cell proliferation and survival rate. shRNA interference experiments further indicated that the activation of the NF-κB pathway was regulated by PARP1. This study confirmed the important role of the NF-κB pathway in HQ-induced DNA damage and cell apoptosis and revealed that the activation of the NF-κB pathway was mediated by PARP1. This research provides important clues for a deeper understanding of the toxic mechanism of HQ.

In-utero exposure to maternal psychological distress is increasingly linked with disrupted fetal and neonatal brain development and long‐term neurobehavioral dysfunction in children and adults. Elevated maternal psychological distress is associated with changes in fetal brain structure and function, including reduced hippocampal and cerebellar volumes, increased cerebral cortical gyrification and sulcal depth, decreased brain metabolites (e.g., choline and creatine levels), and disrupted functional connectivity. After birth, reduced cerebral and cerebellar gray matter volumes, increased cerebral cortical gyrification, altered amygdala and hippocampal volumes, and disturbed brain microstructure and functional connectivity have been reported in the offspring months or even years after exposure to maternal distress during pregnancy. Additionally, adverse child neurodevelopment outcomes such as cognitive, language, learning, memory, social-emotional problems, and neuropsychiatric dysfunction are being increasingly reported after prenatal exposure to maternal distress. The mechanisms by which prenatal maternal psychological distress influences early brain development include but are not limited to impaired placental function, disrupted fetal epigenetic regulation, altered microbiome and inflammation, dysregulated hypothalamic pituitary adrenal axis, altered distribution of the fetal cardiac output to the brain, and disrupted maternal sleep and appetite. This review will appraise the available literature on the brain structural and functional outcomes and neurodevelopmental outcomes in the offspring of pregnant women experiencing elevated psychological distress. In addition, it will also provide an overview of the mechanistic underpinnings of brain development changes in stress response and discuss current treatments for elevated maternal psychological distress, including pharmacotherapy (e.g., selective serotonin reuptake inhibitors) and non-pharmacotherapy (e.g., cognitive-behavior therapy). Finally, it will end with a consideration of future directions in the field.

Steel Circular Hollow Section (CHS) joints have been extensively utilized in construction. Current research mainly focuses on joints reinforced in unloaded states, reinforcement under load less commonly addressed. This study examines the mechanical behavior of CHS T-joints through an experimental analysis of six specimens, each featuring varying brace-to-chord diameter ratios (β), welded under different load factors. Identified primary failure modes of the joints are local buckling and out-of-plane inclination. Furthermore, a thermo-mechanical coupling finite element model, considering the material addition during the welding process, was developed to investigate the influence of the welding under load. The results indicate that welding under axial load has little effect on the ultimate loading capacity of the CHS T-joints. Notably, welding-induced residual deformation on the chord surpasses that on the brace, particularly when welding passes are proximal to the brace-chord intersection. Residual stress in welds is not significantly affected by the stress in the tubular; only the stiffeners near the welds are affected. Despite some joints exhibiting out-of-plane inclination, the enhancement in ultimate bearing capacity exceeds 24%.

Recently, with the development of intelligent manufacturing, the demand for surface defect inspection has been increasing. Deep learning has achieved promising results in defect inspection. However, due to the rareness of defect data and the difficulties of pixelwise annotation, the existing supervised defect inspection methods are too inferior to be implemented in practice. To solve the problem of defect segmentation with few labeled data, we propose a simple and efficient method for semisupervised defect segmentation (SSDS), named perturbed progressive learning (PPL). On the one hand, PPL decouples the predictions of student and teacher networks as well as alleviates overfitting on noisy pseudo-labels. On the other hand, PPL encourages consistency across various perturbations in a broader stagewise scope, alleviating drift caused by the noisy pseudo-labels. Specifically, PPL contains two training stages. In the first stage, the teacher network gives the unlabeled data with pseudo-labels that are divided into the easy and hard groups. The labeled data and the unlabeled data in the easy group with their perturbation are both used to train for a better-performing student network. In the second stage, the unlabeled data in the hard group are predicted by the obtained student network, so the refined pseudo-labeled data are enlarged. All the pseudo-labeling data and labeled data with their perturbation are used to retrain the student network, progressively improving the defect feature representation. We build a mobile screen defect dataset (MSDD-3) with three classes of defects. PPL is implemented on MSDD-3 as well as other public datasets. Extensive experimental results demonstrate that PPL significantly surpasses the state-of-the-art methods across all evaluation partition protocols.

Pulsed magnetic treatment (PMT) has been adopted as an effective strengthening method for engineering materials and components in recent years, and the development of its application depends on the comprehensive understanding of the nature of PMT. The deep mechanism was thought initially to be the magnetostrictive effect, while further investigation found that the magnetic field could lead to the change of the defect states in the crystal, which is called the magnetoplastic effect. Due to the complexity of the engineering materials, manifestations of the magnetoplastic effect become more diverse, and they were reviewed in the form of microstructure homogenization and interfacial stabilization. Further, the mechanism of the magnetoplastic effect was discussed, focusing on the changes in the spin states under the external magnetic field. Microstructure modifications could also alter material performances, especially the residual stress, plasticity, and fatigue properties. Therefore, PMT with specific parameters can be utilized to obtain an ideal combination of microstructure, residual stress, and mechanical properties for better service performance of different mechanical parts, and its applications on machining tools and bearings are perfect examples. This work reviews the effect of PMT on the microstructure and properties of different materials and the mechanism, and it also summarizes the fundamental applications of PMT on essential mechanical parts.

Establishing the theoretical relationship between the unique properties of X-ray photon (large energy, non-dispersive, strong penetrability, etc.) and the link performance is the primary problem needed to be resolved in X-ray communication system design. This paper firstly outlines the research histories of X-ray communication at home and abroad, the effects of link parameters such as the detector sensitivity, the divergence angle and the propagation distance on the propagation loss are studied by numerical simulation. Then, the theoretical link equation of X-ray communication is derived, and the solutions to the key technologies which restricting X-ray communication performance are proposed in the end to provide theoretical support for X-ray application in large capacity and high reliable information transmission in space.

Objective: Our study aims to prospectively compare an autologous duraplasty in situ technique (IS group) with the synthetic dural graft duraplasty (SDG group) to clarify the effectiveness and superiority of the former in the treatment of patients with Chiari malformation type 1 (CM-I). Method: 29 patients with CM-I were randomly assigned to either IS or SDG group. In both groups, a dissection from the occipital bone was performed. All procedures were performed by the same surgeon. The two duraplasty methods were compared in terms of surgical factors and complications. Data analysis was done for the baseline material, the neurological outcome and MRI-documented syrinx size at the 6 month follow-up. Result: 29 patients were enrolled in this study, 14 in the IS group and 15 in the SDG group. The results showed no significant difference in operation time (P= 0.916), amount of bleeding (P= 0.120), operation complications, hospitalization time (P= 0.854) and prognosis between the two groups. The hospitalization cost of IS group was 15,125 yuan less than that of SDG group (P&lt; 0.05). Conclusion: The autogenous duraplasty in situ technique is a novel, simple, effective and economical surgical management for patients with CM-I.

The discovery of unconventional scale-free ferroelectricity in HfO2-based fluorite thin films has attracted great attention in recent years for their promising applications in low-power logic and nonvolatile memories. The ferroelectricity of HfO2is intrinsically originated from the widely accepted ferroelectric metastable orthorhombic Pca21phase. In the last decade, defect-doping/solid solution has shown excellent prospects in enhancing and stabilizing the ferroelectricity viaisovalent or aliovalent defect-engineering. Here, the recent advances in defect-engineered HfO2-based ferroelectrics are first reviewed, including progress in mono-ionic doping and mixed ion-doping. Then, the defect-lattice correlation, the point-defect promoted phase transition kinetics, and the interface-engineered dynamic behaviour of oxygen vacancy are summarized. In addition, thin film preparation and ion bombardment doping are summarized. Finally, the outlook and challenges are discussed. A multiscale structural optimization approach is suggested for further property optimization. This article not only covers an overview of the state-of-art advances of defects in fluorite ferroelectrics, but also future prospects that may inspire their further property-optimization viadefect-engineering.

Sepsis, a life-threatening health issue, lacks effective medicine targeting the septic response. In China, treatment combining the intravenous herbal medicine XueBiJing with conventional procedures reduces the 28-day mortality of critically ill patients by modulating septic response. In this study, we identified the combined active constituents that are responsible for the XueBiJing’s anti-sepsis action. Sepsis was induced in rats by cecal ligation and puncture (CLP). The compounds were identified based on their systemic exposure levels and anti-sepsis activities in CLP rats that were given an intravenous bolus dose of XueBiJing. Furthermore, the identified compounds in combination were assessed, by comparing with XueBiJing, for levels of primary therapeutic outcome, pharmacokinetic equivalence, and pharmacokinetic compatibility. We showed that a total of 12 XueBiJing compounds, unchanged or metabolized, circulated with significant systemic exposure in CLP rats that received XueBiJing. Among these compounds, hydroxysafflor yellow A, paeoniflorin, oxypaeoniflorin, albiflorin, senkyunolide I, and tanshinol displayed significant anti-sepsis activities, which involved regulating immune responses, inhibiting excessive inflammation, modulating hemostasis, and improving organ function. A combination of the six compounds, with the same respective doses as in XueBiJing, displayed percentage survival and systemic exposure in CLP rats similar to those by XueBiJing. Both the combination and XueBiJing showed high degrees of pharmacokinetic compatibility regarding interactions among the six active compounds and influences of other circulating XueBiJing compounds. The identification of XueBiJing’s pharmacologically significant constituents supports the medicine’s anti-sepsis use and provides insights into a polypharmacology-based approach to develop medicines for effective sepsis management.

Two-dimensional (2D) transition metal oxides (TMOs) are promising electrocatalysts for the new energy industry, owing to their earth-abundancy, excellent performance, and unique physicochemical properties. However, microscopic electrochemical study for 2D TMOs is still lacking to provide detailed electrocatalytic mechanisms due to the challenges in synthesizing 2D TMOs with high quality and controlled thickness, which is indispensable for the microscopic studies. In this study, we report the direct synthesis of 2D cobalt ferrite (CoFeO) using a chemical vapor deposition (CVD) method. The as-synthesized 2D CoFeO possesses a well-crystallized spinel structure with an ultrathin thickness of 6.8 nm. Its oxygen evolution reaction (OER) properties under alkaline conditions were accurately assessed using an ultra-microelectrode testing platform. The (111) facet of the 2D CoFeO exhibits a low overpotential of 330 mV at a current density of 10 mA cm–2and a high current density of ~142 mA cm–2at an overpotential of 570 mV. The OER mechanism of the 2D CoFeO was analyzed using density functional theory (DFT) calculations, which reveal the bimetallic sites on the surface reduce the energy barrier and facilitate the reaction. Moreover, we demonstrate the reduced thickness of 2D CoFeO improves the OER activity by lowering the bulk resistance and improving the utilization of active sites, which was confirmed by the thickness-activity dependency (6.8 to 35 nm) tests using the ultra-microelectrode platform. Furthermore, the practical values of the as-prepared 2D CoFeO was demonstrated by synthesizing a large-area continuous film and collecting high OER activity and superb durability from macro-electrochemical experiments. Our study provides new solutions for the controlled synthesis of 2D TMOs electrocatalysts and uncovers the electrocatalytic mechanisms with the ultra-microelectrode platform, which provides new insights for exploring the inherent properties and applications of 2D materials in electrocatalysis.

Camellia azaleacan treat many stubborn and malignant diseases, according to traditional Chinese medicine. In addition, it has been indicated that copper nanoparticles containing the plant have many therapeutic effects. Recently, metallic nanoparticles have been used due to the antioxidant and anti-inflammatory potentials. Present research discloses the CuNPs biosynthesizing capability of the leaves of pharmacologically important Camellia azalea. For determining the physicochemical properties of the recent nanoparticles, FE-SEM, FT-IR, TEM and UV-Vis were used. This study therefore assessed the antiallergic potential of copper nanoparticles in ovalbumin-induced allergic conjunctivitis and attempted to predict its action mode. ELISA test was applied to measure the serum ovalbumin-specific IgG and IgE and total IgE. Clinical scores for allergic conjunctivitis induced by intraperitoneal ovalbumin sensitization and topical conjunctival challenge in Dunkin-Hartley guinea pigs were determined after a week’s daily treatment with 10 mg kg−1chlorpheniramine, 30 mg kg−1prednisolone, 15 and 80 µg kg−1copper nanoparticles, or 10 mL kg−1PBS. The 15 and 60 mg kg−1copper nanoparticles treatment resulted in a significantly (p < 0.01) low clinical score of allergic conjunctivitis. Ovalbumin-specific IgG and IgE as well as total serum IgE also decreased significantly (p < 0.01). The conjunctival tissue in copper nanoparticles treated guinea pigs had mild mononuclear infiltration compared to the PBS-treated ones, which had intense conjunctival tissue inflammatory infiltration.

Aim:To investigate the effect of treatment with fecal microbiota transplantation (FMT) and galacto- and fructo-oligosaccharides on ulcerative colitis (UC) in mice. Materials & methods:A total of 90 mice, divided into nine groups, were administered FMT or prebiotics or combined treatment. The disease activity index scores, gut microbiota and inflammation factors were evaluated. Results:The treatment using FMT combined with galacto- and fructo-oligosaccharides in a 9:1 ratio significantly reduced intestinal barrier damage and alleviated symptoms of UC. Lactobacillusand Bifidobacteriumand short-chain fatty acids were significantly increased after the combined treatment. Conclusion:The results demonstrate that FMT with prebiotics is a new method for UC treatment.

Wildfires are thought to be increasing in severity and frequency as a result of climate change1–5. Air pollution from landscape fires can negatively affect human health4–6, but human exposure to landscape fire-sourced (LFS) air pollution has not been well characterized at the global scale7–23. Here, we estimate global daily LFS outdoor fine particulate matter (PM2.5) and surface ozone concentrations at 0.25° × 0.25° resolution during the period 2000–2019 with the help of machine learning and chemical transport models. We found that overall population-weighted average LFS PM2.5and ozone concentrations were 2.5 µg m−3(6.1% of all-source PM2.5) and 3.2 µg m−3(3.6% of all-source ozone), respectively, in 2010–2019, with a slight increase for PM2.5, but not for ozone, compared with 2000–2009. Central Africa, Southeast Asia, South America and Siberia experienced the highest LFS PM2.5and ozone concentrations. The concentrations of LFS PM2.5and ozone were about four times higher in low-income countries than in high-income countries. During the period 2010–2019, 2.18 billion people were exposed to at least 1 day of substantial LFS air pollution per year, with each person in the world having, on average, 9.9 days of exposure per year. These two metrics increased by 6.8% and 2.1%, respectively, compared with 2000–2009. Overall, we find that the global population is increasingly exposed to LFS air pollution, with socioeconomic disparities.

• A new strategy of introducing high- E p metals into TMNs is proposed for HWCs design. • Adding Ag induces better conductivity than adding Ta due to the E p - τ synergistic effect. • Hf 0.92 Ag 0.08 N solid-solution coatings can be used as new HWCs for harsh environment. Hard and wear-resistant conductors (HWCs) have important applications in the next-generation sliding electrical contacts. However, Cu- and Pt-based alloys, two commonly used HWCs, have very low hardness despite their good electrical conductivity. In this letter, we integrate high hardness, wear resistance, and good electrical conductivity in one material by introducing high-plasma-energy (E p) heterogeneous metals (e.g., Ag or Ta) to transition metal nitrides (e.g., HfN). The obtained solid solution films (such as Hf 0.92 Ag 0.08 N) not only have the good electrical conductivity as traditional HWCs (such as Pt-Ir alloy) but also exhibit much higher hardness and wear resistance than traditional HWCs. Introducing Ag and Ta can improve the hardness and wear resistance of HfN almost equally, but the introduction of Ag can provide better electrical conductivity. This is because the introduction of Ag induces a synergistic effect of E p and relaxation time (τ), while the introduction of Ta results in a competitive effect of E p and τ. Through the combination of first-principles calculations and experiments, we explain the physical mechanisms of these two effects and draw a map of candidate materials with the synergistic effect. Therefore, the new HWC design strategy proposed in this study not only broadens the range of applications for transition metal nitrides but also breaks the bottleneck of integrating high hardness, high electrical conductivity, and wear resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

For millimeter wave massive multiple-input multiple-output systems, the transceiver usually adopts a hybrid precoding structure to reduce complexity and cost, which poses great challenges to the acquisition of channel state information, especially in the case of low signal-to-noise ratio regime. In this article, residual network (ResNet) is employed to address this problem. Firstly, we design a two-stage channel estimation structure to improve the accuracy of channel estimation. Then, we take ResNet as the basic network and integrate UNet structure to build ResNet-UNet model to solve the model degradation problem. Moreover, we use noise2noise algorithm to train the neural network in order to implement the channel estimation in the case that a clean pilot cannot be obtained. Numerical results show that compared with the traditional channel estimation algorithms and deep convolutional neural network algorithm, the proposed approach has higher accuracy and robustness, and achieves performance close to the denoising algorithm using clean targets that is very difficult to be implemented in practical situations.

Simple, commercially available iodine was successfully employed as a highly efficient and chemoselective catalyst for the oxidative annulation of β,γ-unsaturated hydrazones to produce 1,6-dihydropyridazines under mild conditions for the first time. Interestingly, when active β,γ-unsaturated hydrazone compounds containing electron-donating groups, such as furyl, thienyl, and cycloalkyl, were used, pyrroles were obtained. A gram-scale preparation experiment and further derivatization of pyridazines demonstrated the potential applicability of our synthesis method. Experimental studies and density functional theory calculations unveiled the origin of the chemoselectivity determining the formation of different products.

Queue length is one of the most important metrics required for the performance assessment of signalized intersections. However, the current methodology of estimating queue length in the literature suffers from several drawbacks, including unstable estimation and the requirement for multiple data sources. Moreover, for single-channel advance detection, which is a common detection configuration for signal control in many U.S. cities, manual parameter calibration is required. To bridge these gaps, this study proposes a cycle-based maximum queue length estimation method based on: (a) the empirical observation of breakpoints in the time gap between successive actuations; and (b) the identification of queue status for all detector actuations in a cycle. Maximum queue length for cycles with long queues is estimated based on the saturation flow rate and the trajectory of the last vehicle in the queue. The proposed methodology was implemented on two study intersections in Tucson, Arizona. Results showed that using the proposed method, queue length can be estimated with mean absolute percentage errors of 14.77% and 15.1% and mean absolute errors of 25 ft and 42.5 ft. The results showed significant improvement in queue length estimation from single-channel detection data when compared with similar methods in the literature. The proposed method can help transportation agencies accurately estimate queue length at intersections with single-channel advance detection without the need for manual field data collection and without installing lane-by-lane detection.