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ABSTRACTTylosin (TYL) is a kind of antibiotics which promotes the development of animal husbandry, but it poses potential threats to food safety and human health. Therefore, it is necessary to establish a highly sensitive method for the detection of TYL. Here, an enzyme-linked immunosorbent assay (ELISA) combined with biotin–streptavidin (Bio-SA) system and hybridization chain reaction (HCR) technique (Bio-SA-HCR-ELISA) was developed. In the absence of the TYL, a strong fluorescence was generated through double signal amplification as signal output, while in the presence of TYL, the fluorescence intensity decreased. The results showed that the limit of detection for TYL was 0.39 ng/mL, and this method had a good specificity for 9 common antiboics. Compared to the traditional indirect competitive ELISA, the sensitivity of this method was 6.8 times higher. Additionally, the established double signal amplification Bio-SA-HCR-ELISA was used for detecting TYL in milk and honey, the LOD of this method were 4.9 and 2.5 ng/mL, respectively.

Over the years, there has been notable progress in understanding the pathogenesis and treatment modalities of diabetes and its complications, including the application of metabolomics in the study of diabetes, capturing attention from researchers worldwide. Advanced mass spectrometry, including gas chromatography–tandem mass spectrometry (GC-MS/MS), liquid chromatography–tandem mass spectrometry (LC-MS/MS), and ultra-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS), etc., has significantly broadened the spectrum of detectable metabolites, even at lower concentrations. Advanced mass spectrometry has emerged as a powerful tool in diabetes research, particularly in the context of metabolomics. By leveraging the precision and sensitivity of advanced mass spectrometry techniques, researchers have unlocked a wealth of information within the metabolome. This technology has enabled the identification and quantification of potential biomarkers associated with diabetes and its complications, providing new ideas and methods for clinical diagnostics and metabolic studies. Moreover, it offers a less invasive, or even non-invasive, means of tracking disease progression, evaluating treatment efficacy, and understanding the underlying metabolic alterations in diabetes. This paper summarizes advanced mass spectrometry for the application of metabolomics in diabetes mellitus, gestational diabetes mellitus, diabetic peripheral neuropathy, diabetic retinopathy, diabetic nephropathy, diabetic encephalopathy, diabetic cardiomyopathy, and diabetic foot ulcers and organizes some of the potential biomarkers of the different complications with the aim of providing ideas and methods for subsequent in-depth metabolic research and searching for new ways of treating the disease.

Analyzing land subsidence using Multi-temporal Interferometric Synthetic Aperture Radar (MT-InSAR) technology holds significant importance for the secure development of urban areas. Shenzhen, being a crucial component of the Pearl River Delta, faces the threat of land subsidence, similar to most deltaic cities. Numerous studies have already indicated the presence of severe land subsidence in certain localities of Shenzhen. However, due to limitations in data scope and research methodologies, the comprehensive spatial-temporal distribution of land subsidence across the entire city of Shenzhen remains unclear. This study initially employed MT-InSAR technology to process a total of 534 Sentinel-1A SAR images from three different frames (P11F71, P113F71, P11F65), covering the entire city of Shenzhen. This processing resulted in the generation of subsidence rate maps and subsidence time series. Subsequently, the temporal evolution patterns of the subsidence were analyzed while significant subsidence regions were identified. By integrating information from optical images reflecting human activities on the Earth’s surface, the study deduced the subsidence mechanisms in various significant subsidence areas. Research findings indicate that land subsidence in Shenzhen is primarily caused by construction activities, with a concentration in the western coastal areas of Shenzhen, reaching a maximum rate of 80 mm/yr, located at the estuary of Dongbao River (113.770385, 22.745305). The cumulative subsidence from March 2017 to June 2023 amounts to 500 mm. The expansion of the Qinglinjing Reservoir has led to an increased demand for water, resulting in a significant rise in formation pressure and subsequent land subsidence. InSAR land subsidence monitoring and analysis in urban areas can address the spatial and temporal resolution limitations of traditional subsidence monitoring methods, providing effective recommendations for widespread subsidence prevention and control.

Flavonoid compounds have a variety of biological activities and play an essential role in preventing the occurrence of metabolic diseases. However, many structurally similar flavonoids are present in foods and are usually in low concentrations, which increases the difficulty of their isolation and identification. Therefore, developing and optimizing effective extraction and detection methods for extracting flavonoids from food is essential. In this review, we review the structure, classification, and chemical properties of flavonoids. The research progress on the extraction and detection of flavonoids in foods in recent years is comprehensively summarized, as is the application of mathematical models in optimizing experimental conditions. The results provide a theoretical basis and technical support for detecting and analyzing high-purity flavonoids in foods.

Remote sensing satellites are playing very important roles in diverse earth observation fields. However, long revisit period, high cost and dense cloud cover have been the main limitations of satellite remote sensing for a long time. This paper introduces the novel volunteered passenger aircraft remote sensing (VPARS) concept, which can partly overcome these problems. By obtaining aerial imaging data from passengers using a portable smartphone on a passenger aircraft, it has various advantages including low cost, high revisit, dense coverage, and partial anti-cloud, which can well complement conventional remote sensing data. This paper examines the concept of VPARS and give general data processing framework of VPARS. Several cases were given to validate this processing approach. Two preliminary applications on land cover classification and economic activity monitoring validate the applicability of the VPARS data. Furthermore, we examine the issues about data maintenance, potential applications, limitations and challenges. We conclude the VPARS can benefit both scientific and industrial communities who rely on remote sensing data.

Salmonella is a type of common foodborne pathogen of global concern, seriously endangering human health. In molecular biological detection of Salmonella, the method of amplifying DNA often faces the problem of aerosol pollution. In this study, a microfluidic chip was developed to integrate loop-mediated isothermal amplification (LAMP) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system to detect Salmonella. The LAMP reaction solution was initially injected into the chamber to amplify at 65 °C for 20 min; the CRISPR/Cas12a reaction solution was subsequently injected to mix with the amplicons for fluorescent signal production at 43 °C for 30 min. Then, the results can be confirmed by naked eyes under 495 nm light or by a fluorescence immunochromatographic reader. The detection limit of this method for Salmonella DNA was 118 pg/μL. The sensitivity and specificity of this method was 100%. Furthermore, this method was used to detect Salmonella after enrichment for 4 h in salmon and chicken samples spiked with 30 CFU/25 g, and was verified to have a stable detection capability in real samples. The microfluidic chip integrated with the LAMP and CRISPR/Cas12a system not only provides a possibility of highly sensitive endpoint fluorescent visual detection of a foodborne pathogen, but also greatly eliminates the risk of aerosol contamination.

There is broad consensus that many bones of extinct vertebrates contain Rare Earth Elements (REE) and other trace minerals that have been incorporated and enriched into the fossil during diagenesis. During fossilization, apatite minerals in vertebrate bones recrystallize from metastable biogenic forms to thermodynamically more stable inorganic apatite minerals while incorporating REEs from their environment. More than ∼95% of the REE in fossil bones are diagenetically incorporated post-mortem, and bones in different environments have different and distinct REE signatures, generally viewed to be controlled by sedimentological and taphonomic processes. The REE pattern in fossils is generally stable, and the normalized concentration patterns provide unique “fingerprints” or signatures that have been used for various geological and paleontological investigations. The discovery of embryos and their adults at the same site, a previously unrecorded occurrence in the fossil record, allowed us to compare for the first time the relationship between REE concentrations in the same taxon at widely differing ontogenetic stages. Here we compare REE patterns in bones from two distinct sites in Yunnan, China, both preserving embryonic and adult bones of Early Jurassic Sauropodomorpha dinosaurs. These dinosaurs are closely related to each other and close in geological age, and their bones show very similar REE patterns. However, the embryonic bones have significantly lower levels of total REEs when compared to their adult counterparts. We attribute the 10-fold La_REE difference and U concentration 5/1 ratio to the level of ossification of the bones and the dramatically lower concentration of apatites in the embryonic than in the adult bones. We conclude that the ontogenetic stage of fossil materials can have a significant impact on REE concentrations, and discuss the impact of these results on future work.

Summary: The design of blue fluorescent materials combining both deep-blue emission (CIEy

White organic light-emitting diodes (WOLEDs) with higher performance, which have enjoyed application in high-quality lighting sources, are here demonstrated with improved optical and electrical properties. The integration of a novel transparent distributed Bragg reflector (DBR), which consists of periodically alternating layers of atomic layer deposition-fabricated ZrO2/Zircone films and sputtered tin-doped indium oxide into OLEDs microcavities were studied to obtain four-peak electroluminescence (EL) spectra. Three types of OLEDs with two-peak, three-peak, and four-peak EL spectra have been developed. The results of the two-peak spectra show that the DBR structures have an outstanding effect on carrier capture; as a result, the device exhibits a stronger stability in color at various applied voltages. The Commission Internationale de L’Eclairage (CIE) coordinates of the two-peak device at 5–13 V shows few displacements and a negligible slight variation of (±0.01, ±0.01). In addition, the four-peak WOLED also yields a high color purity white emission as the luminance changes from 100 cd m−2 to 10,000 cd m−2.

In this work, an atomic layer deposited (ALD) Al2O3 ultrathin layer was introduced to passivate the ZnO-nanoparticle (NP) buffer layer of inverted polymer solar cells (PSCs) based on P3HT:PCBM. The surface morphology of the ZnO-NP/Al2O3 interface was systematically analyzed by using a variety of tools, in particular transmission electron microscopy (TEM), evidencing a conformal ALD-Al2O3 deposition. The thickness of the Al2O3 layers was optimized at the nanoscale to boost electron transport of the ZnO-NP layer, which can be attributed to the suppression of oxygen vacancy defects in ZnO-NPs confirmed by photoluminescence measurement. The optimal inverted PSCs passivated by ALD-Al2O3 exhibited an ∼22% higher power conversion efficiency than the control devices with a pristine ZnO-NP buffer layer. The employment of the ALD-Al2O3 passivation layer with precisely controlled thickness provides a promising approach to develop high efficiency PSCs with novel polymer materials. [ABSTRACT FROM AUTHOR]

Metal acquisition is a vital microbial process in metal-scarce environments, such as inside a host. Using metabolomic exploration, targeted mutagenesis, and biochemical analysis, we discovered an operon in Staphylococcus aureus that encodes the different functions required for the biosynthesis and trafficking of a broad-spectrum metallophore related to plant nicotianamine (here called staphylopine). The biosynthesis of staphylopine reveals the association of three enzyme activities: a histidine racemase, an enzyme distantly related to nicotianamine synthase, and a staphylopine dehydrogenase belonging to the DUF2338 family. Staphylopine is involved in nickel, cobalt, zinc, copper, and iron acquisition, depending on the growth conditions. This biosynthetic pathway is conserved across other pathogens, thus underscoring the importance of this metal acquisition strategy in infection. [ABSTRACT FROM AUTHOR]