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Author Correction: Thermophilic Hadarchaeota grow on long-chain alkanes in syntrophy with methanogens

A circuit simulation model for resistive random-access memory devices based on CsBi3I10 perovskite thin films

This article proposes a circuit simulation model that can simulate the electrical behaviors of resistive random-access memory (RRAM) devices based on CsBi3I10 perovskite active layer. The CsBi3I10 perovskite thin films were fabricated using a sol-gel method and the structural properties were obtained with x-ray diffraction and scanning electron microscope analysis. The resistive switching memory behaviors of the RRAM devices were studied, showing that the resistance states can be well maintained for a duration of 104 s as well as in 2500 repeated Set/Reset operations during electrical measurements. To simulate the resistive switching behavior, a circuit simulation model was developed. The simulation results yielded good fitting to the experimental results, suggesting promising applications of the proposed model in this work for various kinds of RRAM devices.

Associations of time spent on different types of digital media with self-rated general and mental health in Swedish adolescents

AbstractAlthough previous studies have suggested an association between digital media use and health, detailed knowledge about how different types of digital media impact adolescent health is limited. This cross-sectional population-based study explored the relationship between time spent on various digital media and adolescents’ self-rated general and mental health. The study included 3566 Swedish high school students aged 16–17 years. Associations between time spent on digital media (social media, gaming, watching movies/series/video clips etc. and digital schoolwork) and self-rated health outcomes (general health, self-esteem, symptoms of worry/anxiety and low mood/depression, trust in other people, head/neck/shoulder pain and sleep quality) was assessed. Statistical analyses employed logistic regression models adjusted for covariates (sociodemographic variables and health behaviours). In the adjusted models, spending very high amounts of time (≥ 6 h/day) on any digital media, except schoolwork, was associated with poor self-esteem, symptoms of low mood/depression and poor sleep (ORs 1.35–2.93, p < 0.05). Spending six hours or more on digital media was also associated with worry/anxiety (for social media and gaming), head/neck/shoulder pain (for social media, watching movies/series/video clips and schoolwork), poor general health (for gaming and watching movies/series/video clips) and low trust (for gaming) (ORs 1.39–3.18, p < 0.05). High amounts of time (4–5 h/day) of watching movies/series/video clips was associated with daily symptoms of low mood/depression, neck/shoulder pain, and low trust in other people (ORs 1.46, 1.41, and 1.32, p < 0.05). This study indicates a dose-response relationship between digital media use and adverse health outcomes in adolescents, where adverse associations start to appear after 4–5 h, particularly for watching movies/series/video clips. However, further longitudinal studies, randomized controlled trials and public health interventions focused on healthy and balanced use of digital media are warranted.

Hierarchical representations of relative numerical magnitudes in the human frontoparietal cortex

Mechanism of voltage frequency influence on vibration and discharge characteristics of water droplet attached to electrode

The vibration and discharge phenomena of droplets in electric fields are the focus of various applications, while the relationship between them has not been fully investigated. In this study, a synchronous platform integrating high-speed camera observation and corona current measurement was utilized to explore the influence of voltage frequency on the vibration and corona discharge characteristics of the water droplet attached to the electrode. Results show that the voltage frequency has a significant influence on the vibration and discharge characteristics of the water droplet, and a strong correlation has been observed between these two characteristics. When approaching the dynamic natural vibration range, the droplet will cause a greater water loss due to intensive vibration, resulting in a smaller stable volume and, consequently, a smaller length vibration amplitude and discharge intensity. The forced vibration model has been enhanced to explain these phenomena. The findings further advanced the theory of electro-driven control of the water droplet in vibration and corona discharge.

Study on performance of perforated dew point indirect evaporative coolers

Elastic, strong and tough ionically conductive elastomers

Method to avoid crosstalk for induced flow acceleration in multi-stage dielectric barrier discharge plasma actuators

Dielectric barrier discharge plasma actuators are flow control devices that can actively induce a flow using electrohydrodynamic force. This Letter proposes a configuration of multi-stage dielectric barrier discharge plasma actuators to accelerate the induced flow velocity. In the proposed configuration, the encapsulated and exposed electrodes between adjacent units of the multi-stage plasma actuator are interconnected and share the same potential, thereby avoiding crosstalk phenomena. The thrusts, cross-sectional flow velocity distributions, discharge images, and electric field distributions are examined for the conventional and proposed multi-stage plasma actuators. The results show that the proposed configuration can increase the thrust and induced flow velocity efficiently compared to the conventional one. The discharge images also show that no crosstalk occurs in the proposed configuration. This is mainly due to the low electric field strength in areas where crosstalk would occur.

Research on the acoustic emission characteristics and instability correlation effect of the dynamic response of waste dump slopes

Spatial tumor immune heterogeneity facilitates subtype co-existence and therapy response in pancreatic cancer

AbstractPancreatic ductal adenocarcinoma (PDAC) displays a high degree of spatial subtype heterogeneity and co-existence, linked to a diverse microenvironment and worse clinical outcome. However, the underlying mechanisms remain unclear. Here, by combining preclinical models, multi-center clinical, transcriptomic, proteomic, and patient bioimaging data, we identify an interplay between neoplastic intrinsic AP1 transcription factor dichotomy and extrinsic macrophages driving subtype co-existence and an immunosuppressive microenvironment. ATAC-, ChIP-, and RNA-seq analyses reveal that JUNB/AP1- and HDAC-mediated epigenetic programs repress pro-inflammatory signatures in tumor cells, antagonizing cJUN/AP1 signaling, favoring a therapy-responsive classical neoplastic state. This dichotomous regulation is amplified via regional TNF-α+ macrophages, which associates with a reactive phenotype and reduced CD8+ T cell infiltration in patients. Consequently, combined preclinical anti-TNF-α immunotherapy and chemotherapy reduces macrophages and promotes CD3+/CD8+ T cell infiltration in basal-like PDAC, improving survival. Hence, tumor cell-intrinsic epigenetic programs, together with extrinsic microenvironmental cues, facilitate intratumoral subtype heterogeneity and disease progression.

Coexistence of multiple electronic and phononic nodal lines in a two-dimensional macroporous carbon material

Investigations into topological materials typically emphasize either electronic or phononic properties in isolation, often disregarding their coexistence, which could restrict the full realization of their practical applications. Here, we investigate HOD-graphene, an emergent macroporous carbon material featuring a unique configuration of hexagonal, octagonal, and dodecagonal carbon rings. This distinctive structure imparts exceptional mechanical properties to the material. Using a combination of first-principles calculations and symmetry analysis, we demonstrate that HOD-graphene hosts multiple nodal lines within both its electronic and phononic spectra. For the electronic bands, three nodal lines and several Dirac points manifest near the Fermi energy, generating unconventional electronic properties and distinct topological characteristics. Likewise, the phonon spectrum displays pronounced nodal lines, intricately associated with the material's vibrational modes. Our findings provide a promising platform for exploring the coexistence of electronic and phononic multiple nodal lines in two-dimensional materials, opening avenues for realizing exotic quantum phenomena.

Methylcobalamin-containing nanofiber sheets have better neuroprotective effects than small intestinal submucosa sheets

Tumor microenvironment-responsive engineered hybrid nanomedicine for photodynamic-immunotherapy via multi-pronged amplification of reactive oxygen species

6 kV GaN p–n diode fabricated by hybrid epitaxial growth with regrowth interface treated by CF4 plasma

A high breakdown voltage was achieved for a p–n junction diode grown by a hybrid epitaxial growth. Using a quartz-free hydride vapor-phase epitaxy, a thick and extremely high-purity n−-GaN drift layer was grown on a GaN substrate. A p-GaN layer was grown on the n−-GaN drift layer using metal-organic vapor-phase epitaxy (MOVPE). Before the MOVPE growth, inductively coupled plasma dry etching treatment using CF4 gas was performed on the regrowth surface to reduce the effect of Si contamination. The device with a reduced effective donor sheet concentration at the regrowth interface obtained by the CF4 treatment achieved a high breakdown voltage of 6.23 kV with good diode characteristics. A clear correlation was found between the breakdown voltage and the effective donor concentration at the p–n junction determined by C–V measurements. It is predicted that a breakdown voltage as high as 8 kV can be obtained if the effective donor concentration at the p–n junction is reduced to 1 × 1012 cm−2 or lower.

GYY4137 ameliorates blood brain barrier damage by inhibiting autophagy mediated occludin degradation in cardiac arrest and resuscitation

Swarm navigation of cyborg-insects in unknown obstructed soft terrain

Defect-engineered electrical and optoelectronic properties of WS2 irradiated with 10 MeV protons

Transition metal dichalcogenides (TMDs), particularly tungsten disulfide (WS2), have gained considerable attention due to their versatile electrical and optoelectronic properties, making them promising candidates for next-generation nano(opto)electronic devices. This study investigates the impact of 10 MeV proton irradiation on the electrical and optoelectronic properties of WS2, focusing on the controlled introduction of defects, primarily sulfur vacancies, which are crucial for tailoring material properties and enhancing their capabilities. By varying proton fluences from 1 × 1013 to 5 × 1014 cm−2 at an energy of 10 MeV, the defect density was precisely modulated. The effects of this defect-engineering strategy were characterized using micro-Raman spectroscopy, low-temperature photoluminescence, and density functional theory calculations. Both electronic (field-effect transistor) and optoelectronic (photodetector) devices fabricated with defect-engineered WS2 exhibited a 24-fold decrease in contact resistance and a fivefold improvement in photogain. These results demonstrate the potential of proton irradiation as a powerful tool for defect engineering in TMDs. The findings underscore the promise of this approach for optimizing TMD-based devices for advanced electronic and optoelectronic applications, paving the way for tailored material properties in next-generation technologies.

Investigation of mechanical behavior of slag-stabilized rammed earth reinforced by carpet polyacrylic yarn waste

Anti-aliased metasurfaces beyond the Nyquist limit

Demonstration of asymmetric Hebbian learning based on analog resistive switching in Ag/Co3O4/p-Si memristor

In this work, brain-like experiential learning/forgetting ability is demonstrated with the help of various synaptic adaptation rules, namely, short-term potentiation/short-term depression, long-term potentiation/long-term depression, spike rate-dependent plasticity, and spike-time-dependent plasticity in a thin-film device. The model device used here is a unidirectional thin film of nanocrystalline Co3O4, grown on a p-Si (100) substrate using the pulsed laser deposition technique to fabricate a metal–insulator–semiconductor type memristor. Along with this, we found an analog bipolar-type switching behavior with excellent resistive switching properties in terms of endurance, retention, and ON–OFF ratio suitable for CMOS-based memory applications. The conduction and resistive switching mechanisms are elucidated using a speculative band diagram formulated from the UV-visible spectroscopy data.