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Contrastive learning has achieved remarkable success on various high-level tasks, but there are fewer contrastive learning-based methods proposed for low-level tasks. It is challenging to adopt vanilla contrastive learning technologies proposed for high-level visual tasks to low-level image restoration problems straightly. Because the acquired high-level global visual representations are insufficient for low-level tasks requiring rich texture and context information. In this article, we investigate the contrastive learning-based single-image super-resolution (SISR) from two perspectives: positive and negative sample construction and feature embedding. The existing methods take naive sample construction approaches (e.g., considering the low-quality input as a negative sample and the ground truth as a positive sample) and adopt a prior model (e.g., pretrained very deep convolutional networks proposed by visual geometry group (VGG) model) to obtain the feature embedding. To this end, we propose a practical contrastive learning framework for SISR (PCL-SR). We involve the generation of many informative positive and hard negative samples in frequency space. Instead of utilizing an additional pretrained network, we design a simple but effective embedding network inherited from the discriminator network, which is more task-friendly. Compared with the existing benchmark methods, we retrain them by our proposed PCL-SR framework and achieve superior performance. Extensive experiments have been conducted to show the effectiveness and technical contributions of our proposed PCL-SR thorough ablation studies. The code and resulting models will be released via https://github.com/Aitical/PCL-SISR.

Ga2O3is a promising material for deep-ultraviolet (DUV) photodetectors due to its ultra-wide bandgap and high thermal and chemical stability. However, because of their relatively low responsivity, Ga2O3-based photodetectors still have difficulty meeting the requirements of practical applications. Here, we construct a high-performance Ga2O3photodetector realized by back-illumination. Utilizing high-crystallinity epitaxially grown Ga2O3as the DUV absorbing layer and the double-polished Al2O3substrate as the transparent window for injection of photons, the device operating in the back-illuminated mode exhibits a higher DUV photoresponse and faster response speed than in the front-illuminated mode. Therefore, our experimental results have led to the development of a novel strategy for designing and fabricating high-performance Ga2O3photodetectors.

Negative ions are crucial in various scientific and technological fields, such as antimatter research, interstellar chemistry, accelerator-based radionuclide dating, fusion injection for controlled nuclear fusion, and neurological disease treatment. Thus, producing a large number of negative ions is highly important. Herein, we present the first theoretical evidence of a large fraction of negative-ion formation during the grazing scattering of carbon atoms from a CsI(100) surface. The conversion efficiency of the negative ions reaches ≥86% within a projectile energy range of Ep∈ [5,10] keV. These remarkable results are attributed to large anion and cation polarizations, which lead to an evidently large Mott–Littleton polarization interaction. This interaction lowers the energy defect of valence band electron capture to below 1.8 eV near the surface anion sites, drastically increasing the electron-capture probability. The destruction of negative ions occurs owing to affinity electron detachment via the Coulomb barrier tunneling to the vacuum level during the interactions with surface anion sites along their trajectories. Our results indicate that this collision system can be used to design next-generation negative carbon ion sources for studying the isotope shift of electron affinity and provide insights into electron correlation effects and molecular-level irradiation pathological studies, especially for promoting nerve tissue repair and regeneration through Ep∈ [5,10] keV negative carbon ion irradiation.

ABSTRACTElectric shared mobility is flourishing in urban transportation. However, the problem of uneven vehicle distribution and untimely vehicle charging hampers user trip experience and system operation efficiency. To overcome these challenges, this study proposed a multi-phase vehicle relocation optimization approach for one-way station-based carsharing systems. In phase one, a micro-level shared travel demand forecasting model was developed to capture the number of orders in the short-term future. In phase two, stations were divided into different categories based on the results of user travel demand forecast. In phase three, the minimization of driving mileage and carbon emissions was taken as the optimization objective, and a solution method combining Gurobi solver and charging priority ranking was designed. Finally, the effectiveness and advantages of the proposed model and algorithm were comprehensively validated through a case study using real passenger orders and geographic data from the city of Shanghai, China.

Objective: Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) are widely expressed in the brain and are associated with the development of neurological and neurodegenerative diseases. However, their roles and molecular mechanisms in major depressive disorder (MDD) remain largely unknown. This study aimed to identify lncRNAs and miRNAs involved in the development of MDD and elucidate their molecular mechanisms. Methods: Transcriptome and bioinformatic analyses were performed to identify miRNAs and lncRNAs related to MDD. C57 mice were subjected to chronic unpredictable mild stress (CUMS) to establish a depression model. Lentiviruses containing either lncRNA NPTN-IT1-201 or miR-142-5p were microinjected into the hippocampal region of these mice. Behavioral tests including the sucrose preference test (SPT), tail suspension test (TST), and forced swim test (FST) were conducted to evaluate depressive-like behaviors. Results: The results revealed that overexpression of lncRNA NPTN-IT1-201 or inhibition of miR-142-5p significantly ameliorated depressive-like behaviors in CUMS-treated mice. Dual-luciferase reporter assays confirmed interactions between miR-142-5p with both brain-derived neurotrophic factor (BDNF) and NPTN-IT1-201. ELISA analysis revealed significant alterations in relevant biomarkers in the blood samples of MDD patients compared to healthy controls. Histological analyses, including HE and Nissl staining, showed marked structural changes in brain tissues following CUMS treatment, which were partially reversed by lncRNA NPTN-IT1-201 overexpression or miR-142-5p inhibition. Immunofluorescence imaging demonstrated significant differences in the levels of BAX, Bcl2, p65, Iba1 among different treatment groups. TUNEL assays confirmed reduced apoptosis in brain tissues following these interventions. Western blotting showed the significant differences in BDNF, BAX, and Bcl2 protein levels among different treatment groups. Conclusion: NPTN-IT1-201 regulates inflammation and apoptosis in MDD by targeting BDNF viamiR-142-5p, making it a potential therapeutic target for MDD.

Long non-coding RNAs (lncRNAs) play an important role in tumor progression. Numerous studies show that lncRNAs are strongly associated with prostate cancer (PCa) progression. The aim of this study was to investigate the pathway through which lncRNA HCG18regulates PCa progression by bioinformatics analysis and experiments.

The pursuit of high-performance thermoelectric materials is of paramount importance in addressing energy sustainability and environmental concerns. Here, we explore the multifaceted impact of sulfur passivation in the matrix of tellurium nanowires (TeNWs), encompassing environmental control, thermoelectric properties, and charge carrier mobility. In this study, we present the facile production of TeNWs using an aqueous solution synthesis approach. The synthesized TeNWs were subsequently subjected to surface modification involving sulfur moieties. Our findings demonstrate that sulfur passivation not only effectively safeguards the nanowires from environmental degradation but also significantly augments their thermoelectric properties. Notably, the highest recorded values were achieved at 560 K for passivated tellurium nanowires, exhibiting a Seebeck coefficient of 246 μV/K, an electrical conductivity of 14.2 S/cm, and power factors of 86.7 μW/m-K2. This strategy presents a promising avenue for the development of advanced thermoelectric materials for applications in energy harvesting, waste heat recovery, and sustainable energy conversion technologies.

Silicon oxide (SiOx) is heralded as the forefront anode material for high-energy density lithium-ion batteries, owing to its exceptional specific capacity. Nevertheless, the traditional combination of polyacrylic acid binder and acetylene black conductive carbon continues to struggle with the immense stress induced by the repetitive volume expansion and contraction processes. Here we report a high ionic conductivity, sulfonyl fluoro-containing binder for SiOxanode via free radical copolymerization reaction between perfluoro (4-methyl-3,6-dioxaoct-7-ene) sulfonyl fluoride and acrylic acid. The electrode fabrication process incorporated amino-functionalized carbon nanotubes (CNT-NH2) as the conductive agent. A three-dimensional conductive network structure is constructed through physical and chemical double cross-linking interactions between the -COOH and -SO2F functional groups of PAF0.1binder, the -NH2groups of CNT-NH2, and the -OH groups on the surface of SiOx, including hydrogen bonds and covalent bonds. In addition, the binder induces the formation of a solid electrolyte interphase (SEI) rich in inorganic components such as Li2O, Li2SO3, Li2CO3, and LiF. Benefiting from the synergistic effects of the physically and chemically double cross-linked three-dimensional conductive network constructed by the PAF0.1binder and CNT-NH2, coupled with the rich-inorganic SEI, the SiOxanode delivers exceptional rate performance, cycle stability, and lithium-ion diffusion dynamics. A high ionic conductivity, sulfonyl fluoro-containing binder for SiOxanode is fabricated via free radical copolymerization reaction between perfluoro (4-methyl-3,6-dioxaoct-7-ene) sulfonyl fluoride (PFSF) and acrylic acid (AA). The binder presents physically and chemically double cross-linked three-dimensional conductive network and induces the formation of a solid electrolyte interphase (SEI) rich in inorganic components such as Li2O, Li2SO3, Li2CO3, and LiF.

Artificial noise elimination (ANE) has arisen as a promising strategy to counteract artificial noise (AN) at the eavesdropper (Eve). However, conventional ANE schemes rely on the attainable channel state information (CSI) between the transmitter (Alice) and legitimate receiver (Bob), which may reduce the feasibility of ANE. To break the gridlock, we focus on the ANE without the Alice-Bob link CSI by minimizing the artificial-noise-to-signal ratio (ANSR). Specifically, the detailed minor component analysis (MCA)-based ANE scheme is proposed to eliminate the AN for a specific classification. Moreover, the principal component analysis (PCA)-based ANE scheme is proposed for the case of binary phase shift keying (BPSK). Furthermore, the k-nearest neighbor (kNN)-based ANE scheme is proposed to exploit the additional information from the unclassified samples. To evaluate the cost of computing, the computational complexity of the aforementioned ANE schemes is analyzed. Meanwhile, the minimum required numbers of observed vectors for the MCA and PCA are derived. Finally, our numerical simulations show that proposed ANE schemes outperform the conventional hyperplane clustering (HC) scheme and can achieve the ANSR of ${\mathbf {1}}{{\mathbf {0}}^{{\mathbf { - 4}}}}$ at the signal-to-noise ratio (SNR) of 25 dB.

A novel multifunctional separator, primarily composed of Zn2+-phytate coordination complex nanoparticles, has been prepared. Through coupling with fluoride-free wide-temperature-range electrolyte, environmentally friendly lithium batteries exhibit excellent electrochemical performance and safety.

AbstractObjectiveThis investigation aimed to develop and validate a novel oxidative stress score for prognostic prediction in locally advanced cervical cancer (LACC) patients receiving chemoradiotherapy.MethodsA total of 301 LACC patients were enrolled and randomly divided into a training and a validation set. The association between oxidative stress parameters and prognosis was analyzed for oxidative stress score (OSS) establishment. A Cox regression model was conducted for overall survival (OS) and progression-free survival (PFS). A nomogram prediction model was developed using independent prognostic factors from the training set and validated in the validation set.ResultsA novel OSS was established with four oxidative stress parameters, including albumin, total bilirubin, blood urea nitrogen, and lactate dehydrogenase. Multivariate regression analysis identified OSS as an independent prognostic factor for OS (p = 0.001) and PFS (p < 0.001). A predictive nomogram based on the OSS was established and validated. The C-indexes of the nomogram in the training set were 0.772 for OS and 0.781 for PFS, while in the validation set the C-indexes were 0.642 for OS and 0.621 for PFS.ConclusionThis study confirmed that preoperative OSS could serve as a useful independent prognostic factor in LACC patients who received CCRT.

Noble gases with inert chemical properties have rich bonding modes under high pressure. Interestingly, Xe and Xe form covalent bonds, originating from the theoretical simulation of the pressure-induced decomposition of XeF2, which has yet to be experimentally confirmed. Moreover, the structural phase transition and metallization of XeF2under high pressure have always been controversial. Therefore, we conducted extensive experiments using a laser-heated diamond anvil cell technique to investigate the above issues of XeF2. We propose that XeF2undergoes a structural phase transition and decomposition above 84.1 GPa after laser heating, and the decomposed product Xe2F contains Xe–Xe covalent bonds. Neither the pressure nor temperature alone could bring about these changes in XeF2. With our UV–vis absorption experiment, I4/mmm-XeF2was metalized at 159 GPa. This work confirms the existence of Xe–Xe covalent bonds and provides insights into the controversy surrounding XeF2, enriching the research on noble gas chemistry under high pressure.

In order to reduce energy consumption in water electrolysis, it is of great importance to design active and stable electrocatalysts for hydrogen evolution reaction (HER) in alkaline solution, especially based on earth-abundant metal. Here we integrate carbon nanotubes (CNTs) and Ni-Ni(OH)2heterostructure multifunctional components to design a self-supported 3D CNTs-Ni-Ni(OH)2catalyst for HER by composite deposition and subsequent in-situoxidation. In alkaline solution, this designed CNTs-Ni-Ni(OH)2catalyst exhibits 0 mV onset overpotential, and overpotentials of 65 mV and 109 mV at 10 and 50 mA/cm2respectively. Electrochemical measurements, characterizations, and simulation results attribute the outstanding performance to the incorporation of CNTs and heterostructure. CNTs induce the formation 3D catalytic surface, enhance electrochemical active surface area, and more importantly weaken the adsorption of H. Moreover, the formation of heterostructure, especially reversible Ni(OH)2, supplies active sites and adjusts the adsorption strength of H atom to an optimal value. CNTs and heterostructure synergistically facilitate water adsorption, promote water dissociation, and accelerate H2desorption. Significantly, integration of multifunctional components supplies a distinct strategy for development of cost-effective electrocatalyst with outstanding performance.

•Heterozygous carriers of deleterious germ line NBNvariants are at risk of B-ALL development.•Protein instability is the main mechanism for loss-of-function variants in the NBNgene.

Transition metal chalcogenides (TMCs) with 3d orbitals have been intensively studied for use as cathodes in magnesium-ion batteries. However, their poor electronic conductivities and sluggish electrochemical kinetics severely restrict their electrochemical performance, preventing wide applicability for these materials. Here, we propose a heterointerface structure of cobalt sulfide (Co3S4/CoS2) hollow nanospheres to enable built-in electric fields generated in heterointerfaces, as verified in density functional theory, finite-element simulations, and ab initiomolecular dynamics results. Compared to other TMCs, our cathode exhibited a substantial capacity of 597 mAh g−1after 120 cycles at 50 mA g−1. When evaluated in a pouch cell, the electrode can sustain 100 deep cycles at 40 mA g−1with an energy density of 203 Wh kg−1that displays potential for practical applications. Finally, rational heterostructure engineering of transition-metal-based sulfides provides insights into developing cathodes for high-performance sustainable Mg batteries.

Here, we present a versatile modular strategy for crafting novel covalent organic cages (para-cage[n]arenes and meta-cage[n]arenes, n= 3,4) and bimacrocycles (meta-bimacrocyclic-arenes) with stable backbones and modifiable rims. These structures can be synthesized from commercially available aromatic multialdehydes in a three-step process: quantitative bromination, Suzuki–Miyaura reaction (yielding over 60%), and a rapid one-pot Friedel–Crafts reaction with paraformaldehyde. Notably, the cage[n]arenes exhibit a well-defined prismatic shape, and the bimacrocyclic-arenes display both dimeric and monomeric configurations.

Research has shown that neuronal ferroptosis is associated with various central nervous system diseases, including Parkinson’s disease, acute brain injury, and spinal cord injury. Inhibiting neuronal ferroptosis can greatly alleviate the progression of these diseases. However, there is currently a lack of effective drugs to inhibit neuronal ferroptosis. In this study, we pretreated neuronal cells with Hispolon and subsequently induced a neuronal ferroptosis model using Erastin. We further assessed the changes in the protein expression levels of SLC7A11, GPX4, ACSL4, Nrf-2, and HO-1 using Western blot and immunofluorescence techniques. Additionally, we measured the intracellular levels of Fe2+, GSH, and MDA using relevant assay kits. The research findings revealed that after Hispolon treatment, the expression of the pro-ferroptosis protein ACSL4 decreased, while the expression of the ferroptosis-regulating proteins GPX4 and SLC7A11 increased. Moreover, the use of an Nrf-2-specific inhibitor was able to reverse the effects of Hispolon as mentioned above. In this study, we discovered that Hispolon can promote the expression of Nrf-2 and inhibit the occurrence of neuronal ferroptosis induced by Erastin.

In this work, particulate matter (PM) emissions from a large two-stroke, low-speed marine diesel engine were investigated when the engine was operated with low-sulfur heavy fuel oil (HFO) at various loads. Particle samples were collected in situ from the engine exhaust to determine the detailed physical and chemical properties. The nanostructure and morphology of the nanoparticles were analyzed using transmission electron microscopy images (TEM). The results show that volatile organic carbon (OC) accounts for more than 80% in the HFO particles and leads to an increase in particle size. The thermodynamic conditions of a low-speed engine favor the behavior of capturing the soluble organic components. A large number of spherical char HFO particles with aerodynamic diameters of 0.2 μm–0.5 μm and a suspected inner metal core were detected. The two peak aerodynamic diameters of the HFO nanoparticles are 15 nm and 86 nm. The morphological differences among the HFO nanoparticles in varied engine conditions represent the formation process from primary nascent particles to mature graphitized particles caused by thermodynamics. The above study will be valuable for understanding the characteristics of PM emissions from low-sulfur HFO to achieve the ship PM emissions reduction target.

The effects of heavy fuel oil and biodiesel blends on engine combustion and emissions were studied in a marine two-stroke diesel engine. The engine was operated under propeller conditions using five different fuels with biodiesel blends of 10% (B10), 30% (B30), 50% (B50), and sulphur contents of 0.467% low sulphur fuel oil (LSFO) and 2.9% high sulphur fuel oil (HSFO). Tests have shown that using a biodiesel blend increases the engine fuel consumption due to its lower calorific value. Heavy fuel oil has a high Polycyclic aromatic hydrocarbons (PAH) content, which leads to higher exhaust temperatures due to severe afterburning in the engine. A comparison of engine soot emissions under different fuel conditions was carried out, and it was found that the oxygen content in biodiesel promoted the oxidation of soot particles during the combustion process, which reduced the soot emissions of biodiesel. Compared to HSFO, B10, B30, B50 and LSFO, the soot emission concentrations were reduced by 50.2%, 56.4%, 61% and 37.4%, respectively. In our experiments, the soot particles in the engine exhaust were sampled with a thermal float probe. Using Raman spectroscopy analysis, it was found that as the biodiesel ratio increased, the degree of carbonisation of the soot particles in the exhaust became less than that in the oxygenation process, resulting in a decrease in the degree of graphitisation.

Long-acting neuromuscular blocks followed by rapid reversal may provide prolonged surgeries with improved conditions by omitting repetitive or continuous administration of the neuromuscular blocking agent (NMBA), eliminating residual neuromuscular block and minimizing postoperative recovery, which, however, is not clinically available. Here, we demonstrate that imidazolium-based macrocycles (IMCs) and acyclic cucurbit[n]urils (ACBs) can form such partners by functioning as long-acting NMBAs and rapid reversal agents through a pseudo[2]catenation mechanism based on stable complexation with Kavalues of over 109M–1. In vivo experiments with rats reveal that, at the dose of 2- and 3-fold ED90, one IMC attains a duration of action corresponding to 158 or 442 min for human adults, covering most of prolonged surgeries. The block can be reversed by one ACB with recovery time significantly shorter than that achieved by sugammadex for reversing the block of rocuronium, the clinically most widely used intermediate-acting NMBA.

A chemically closed-loop-recyclable biodegradable polymer, poly(p-dioxanone) (PPDO), is one of the ideal candidates for single-use plastic products due to its suitability for different application scenarios. Fascinatingly, when PPDO wastes can be collected, its monomer p-dioxanone (PDO) will be obtained through chemical recycling of these wastes; when cannot be collected, the wastes are able to be biodegraded into harmless substances. However, unsatisfied thermal stability and low crystallization rate of PPDO restrict its wider applications. Herein, based on end-group regulation, we simultaneously realized the significant enhancement of thermal stability and crystallization of PPDO through the simple melt processing with tributyl phosphite (TBP) or triphenyl phosphite (TPP). The model reactions were conducted to investigate the reaction mechanism and theoretical products during the preparation of PPDO/phosphite compounds. Two kinds of phosphites were proved to act as the end-capped reagent and chain extender in the melt processing, while TBP presented better reactivity. As a result, the activation energy of thermal decomposition was largely elevated, and the unprecedented T5%(the temperature at a weight loss of 5%) and Tmax(the temperature at a maximum rate of weight loss) of PPDO were obtained, i.e., T5%of ~330 °C and Tmaxof ~385 °C in N2atmosphere, T5%of ~240 °C and Tmaxof ~317 °C in air atmosphere, respectively. Furthermore, the increased crystallization rate, crystallinity, crystalline orderliness, and realizable monomer recovery (yield >90%, purity >99.9%) of PPDO/phosphite compounds were confirmed.

Cu-based catalysts hold promise for electrifying CO2to produce methane, an extensively used fuel. However, the activity and selectivity remain insufficient due to the lack of catalyst design principles to steer complex CO2reduction pathways. Herein, we develop a concept to design carbon-supported Cu catalysts by regulating Cu active sites’ atomic-scale structures and engineering the carbon support’s mesoscale architecture. This aims to provide a favorable local reaction microenvironment for a selective CO2reduction pathway to methane. In situ X-ray absorption and Raman spectroscopy analyses reveal the dynamic reconstruction of nitrogen and hydroxyl-immobilized Cu3(N,OH-Cu3) clusters derived from atomically dispersed Cu–N3sites under realistic CO2reduction conditions. The N,OH-Cu3sites possess moderate *CO adsorption affinity and a low barrier for *CO hydrogenation, enabling intrinsically selective CO2-to-CH4reduction compared to the C–C coupling with a high energy barrier. Importantly, a blockcopolymer-derived carbon fiber support with interconnected mesopores is constructed. The unique long-range mesochannels offer an H2O-deficient microenvironment and prolong the transport path for the CO intermediate, which could suppress the hydrogen evolution reaction and favor deep CO2reduction toward methane formation. Thus, the newly developed catalyst consisting of in situ constructed N,OH-Cu3active sites embedded into bicontinuous carbon mesochannels achieved an unprecedented Faradaic efficiency of 74.2% for the CO2reduction to methane at an industry-level current density of 300 mA cm–2. This work explores effective concepts for steering desirable reaction pathways in complex interfacial catalytic systems via modulating active site structures at the atomic level and engineering pore architectures of supports on the mesoscale to create favorable microenvironments.