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Two-dimensional nanomaterials are used in biosensors due to their unique physical and chemical properties, which have many advantages in the development of biosensors, such as improving the response speed, improving the detection sensitivity, shortening the detection time and simplifying the operation procedure. In recent years, they have shown great application prospects in the field of food safety detection and have gradually become a hot research topic. Based on an analysis of the application of two-dimensional nanomaterials including graphene, graphene alkyne, and graphene-like materials in the field of analytical sensing, this paper reviews the progress that has been made in the past five year in the application of two-dimensional nanomaterials in the detection of organic pollutants in foods, food additives, foodborne pathogens and heavy metals, and also presents an outlook on future prospects. This review is expected to provide ideas and theoretical references for researchers.

Microfluidic chips hold vast potential for applications in fields such as DNA analysis, drug screening, cell culture and biosensing. However, microfluidic chips are susceptible to disruption and damage from bubbles. Current bubble removal methods suffer from limitations including narrow applicability, poor biocompatibility, limited bubble containment volume, low degassing rates, manufacturing complexity and integration challenges. Addressing these issues, this study presents the development of a bubble filtration microfluidic chip inspired by the stomatal pore structure in plant leaves, which prevents air propagation between conduits. Surface wettability theory and surface tension principles were utilized to investigate the mechanism of bubble filtration by plant stomatal pores. A cellulose/PVA hydrogel was introduced to enable the microfluidic chip to effectively filter bubbles. The design and in situ formation method of the bubble filtration chip were developed, and the chip was fabricated using micro-nanofabrication processes. Performance evaluation of the bubble filtration microfluidic chip demonstrated that with a gel film thickness of 20 μm, the microfluidic chip exhibits high gas leak threshold and minimal flow loss. The resulting biomimetic bubble filtration microfluidic chip features a simple structure, compact size, and independence from auxiliary equipment, making it suitable for portable microfluidic devices. [ABSTRACT FROM AUTHOR]

Activating transcription factor 4 (ATF4) is a fundamental basic region/leucine zipper transcription factor, responds to various stress signals, and plays crucial roles in normal metabolic and stress response processes. Although its functions in human health and disease are not completely understood, compelling evidence underscores ATF4 is indispensable for multiple stages and lineages of erythroid development, including the regulation of fetal liver hematopoietic stem cells, induction of terminal erythroid differentiation, and maintenance of erythroid homeostasis. β -Thalassemia is a blood disorder arising from mutations in the β -globin gene. Reactivating the expression of the γ -globin gene in adult patients has emerged as a promising therapeutic strategy for ameliorating clinical symptoms associated with β -thalassemia. Recent research has suggested that ATF4 contributes to decreased fetal hemoglobin (HbF) level through its binding to potent negative regulators of HbF, such as BCL11A and MYB. Notably, evidence also suggests a contrasting outcome where increased ATF4 protein levels are associated with enhanced HbF at the transcriptional level. Consequently, the identification of mechanisms that modulate ATF4-mediated γ -globin transcription and its effects on erythroid development may unveil novel targets for β -thalassemia treatment. [ABSTRACT FROM AUTHOR]

Nuclear batteries, a novel energy device in microelectromechanical systems (MEMS), have garnered significant attention from academia and industry due to their promising application prospects. They possess high energy density and reliable operation without human intervention and offer unique advantages in the case of long-term stable power supply. Among these, thermal conversion nuclear batteries (RTGs) represent the most mature technology and the earliest application, while betavoltaic nuclear batteries have entered commercialization. Challenges in betavoltaic nuclear batteries research include energy wastage due to the self-absorption effect of radioactive sources, low conversion efficiency, and significant radiation damage to transducer devices. These issues are attributable not only to the inherent properties of the radioactive source but also to the material and structural design of transducers. A 3D interface structure design scheme based on the wide bandgap semiconductor material GaN and the radioactive isotope 63Ni nuclear microbatteries is proposed. In the scheme, Geant4 and COMSOL Multiphysics were used to simulate the GaN-based betavoltaic nuclear battery of 63Ni source, and the PN junction 3D interface structure of the transducer was designed and optimized. The effects of the surface area, number of micropillars, thickness, and doping concentration of each region on the battery performance were analyzed. Results indicate that with P- and N- region thicknesses and doping concentrations at 0.1, 9.9 µm, 1 × 1018, and 1 × 1014 cm−3, respectively, the nuclear battery can achieve a conversion efficiency of 7.57%, a short-circuit current density of 0.3959 µA/cm2, an open-circuit voltage of 2.3074 V, and maximum output power of 0.7795 µW/cm2. In addition, discussion regarding the surface area and quantity of P-layer micropillars confirms the hypothesis that these variables are positively correlated with the output performance of the transducer. [ABSTRACT FROM AUTHOR]

Aerosols play an important role in the Earth system, but their impact on cloud properties and the resulting radiative forcing of climate remains highly uncertain. The large temporal and spatial variability of a number of aerosols properties and the choice of different 'pre-industrial' reference years prevent a concise understanding of basic underlying patterns and trends in aerosols and their impacts on clouds and radiation. In this study, we characterize the spatial patterns and long-term evolution of lower tropospheric aerosols (in terms of regimes) by clustering multiple aerosol properties from preindustrial times to the year 2050 under three different Shared Socioeconomic Pathway (SSP) scenarios, based on a combination of global aerosol model simulations and statistic-based machine learning algorithms. Our analysis suggests that in comparison with the present-day case, lower tropospheric aerosol regimes during preindustrial times are mostly represented by regimes of comparatively clean conditions whereby marked differences between the years 1750 and 1850 emerge due to the growing influence of agriculture and other anthropogenic activities in 1850. Key aspects of the spatial distribution and extent of the aerosol regimes identified in year 2050 differ compared to pre-industrial and present-day, with significant variations resulting from the emission scenario investigated. In 2050, the low emission SSP1-1.9 scenario is the only scenario where the spatial distribution and extent of the aerosol regimes very closely resembles preindustrial conditions whereby the similarity is greater compared to 1850 than 1750. The aerosol regimes for 2050 under SSP3-7.0 closely resemble present-day conditions, but there are some notable regional differences: developed countries tend to shift towards cleaner conditions in future, while the opposite is the case for developing countries. The aerosol regimes for 2050 under SSP2-4.5 represent an intermediate stage between preindustrial times and present-day. Further analysis indicates a north/south difference in the background regime during preindustrial times, and close resemblance of pre-industrial aerosol conditions in the marine regime to present-day conditions in the Southern Hemispheric ocean. Overall, our study allows to extract a clear and condensed picture of the spatial extent and distribution of aerosols for different time periods and emission scenarios and to summarize these in terms of aerosol regimes. The approach and findings of this study can be used for designing targeted measurements of different preindustrial-like conditions, and for tailored air pollution mitigation measures in specific regions. [ABSTRACT FROM AUTHOR]

A precursor film is a unique microfluidic entity that arises at the liquid/solid interface. The formation mechanism of this entity in high-temperature systems is yet to be explained, mainly due to the limitations posed by the increased reaction at the solid/liquid interface. In this study, we investigate the formation process of the precursor film in high-temperature molten metal systems (Ag/Ni, Au/Ni, and Cu/Ni) using molecular dynamics simulations. The alloying energies for different alloying pairs were determined to extract the excess energy, which was found to be distributed from the interface to the upper liquid. The pattern of this energy distribution determines the shape of the near-surface liquid, including the precursor film. This relationship is further reflected by the structural disjoining pressure, which is the excess pressure exerted by the ordered microstructures within the wedge-shaped area of the droplet. Strong nonlinearity has been found in the structural disjoining pressure of Ag/Ni and Au/Ni systems, which is considered to be the main reason for the formation of the precursor film. The fluctuation of the dissolution rate is also reflected in the disjoining pressure, and the inhibition of dissolution on the precursor film formation is phenomenally clarified. [ABSTRACT FROM AUTHOR]