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Passive IoT-based positioning systems are low-cost and taggable, making them suitable for scenarios that require the positioning of a large number of targets. Traditional passive IoT positioning is mostly applied to indoor scenarios such as asset management, material tracking. With the emergence of cellular passive IoT, passive IoT positioning technology will have a broader range of applications. On the basis of analyzing the principles and characteristics of different positioning technologies, the latest research progress of passive IoT positioning was introduced, and the passive IoT positioning technologies were summarized into three categories: geometrical measurement-based positioning methods, fingerprint feature-based positioning methods, and imaging technology-based positioning methods, according to their implementation principles. In view of the fact that most of the current research adopted the data obtained under the traditional passive IoT architecture and protocol for localization, the future development direction of passive IoT positioning technology was analyzed from three dimensions: architectures, protocols and data. The aim is to provide new ideas for researching passive IoT positioning technology.

The rapid growth of the alumina industry has significantly increased red mud production, with each ton of alumina yielding 0.8 to 1.5 tons of this byproduct. Red mud is a highly alkaline residue produced during bauxite refining, containing various metals including chromium (Cr) and vanadium (V), which pose significant environmental risks if not properly treated. Effective management and valorization of red mud are essential to mitigate environmental contamination and exploit its economic potential. Phytomining, a bioremediation strategy utilizing hyperaccumulator plants, offers a promising method for extracting economically valuable metals from red mud. This study investigates the phytomining capacity of Jatropha curcas and Sansevieria trifasciata to uptake Cr and V from red mud amended with a 5% sludge-manure mixture. The experiment was conducted over a 28-day period, during which both species were cultivated in red mud media with the amendment. The phytomining capacity of the plants was determined by measuring the metal accumulation, analyzed on days 0, 14, and 28 using acid digestion and ICP-OES analysis. Results showed that both plant species preferentially accumulated metals in their root systems rather than in their aerial parts. Jatropha curcas absorbed 1.6 mg/kg of Cr and 2.9 mg/kg of V, while Sansevieria trifasciata exhibited higher uptake, with 2.5 mg/kg of Cr and 4 mg/kg of V. These findings highlight the phytomining potential of these species in recovering valuable metals from red mud.

The highly alkaline nature of red mud, coupled with the presence of heavy metals, represents a significant environmental risk. Phytomining has the potential to facilitate the extraction of heavy metals, including vanadium (V) and chromium (Cr), from red mud. In this study, phytomining employs the use of Cymbopogon citratus and Portulaca grandiflora plants. The objective of this study is to evaluate the capacity of both plants to engage in phytomining and extract valuable metals from red mud. The methodology employed in this study entails the incorporation of stimulants in the form of manure at concentrations of 0%, 5%, and 10%. The study was conducted over a period of 28 days, during which time toxicity testing and the phytomining ability of the two plants were observed. The phytomining capacity of the plants was determined by measuring the concentration of vanadium (V) and chromium (Cr) in the plant extractions using inductively coupled plasma-optical emission spectroscopy (ICP-OES) equipment. The findings indicated that the Cymbopogon citratus and Portulaca grandiflora plants were capable of surviving on a red mud medium with the addition of 10% manure. The highest absorption of V metal was observed in Cymbopogon citratus, with a value of 23.3 mg/kg, when 10% manure and 90% red mud were added. The highest absorption of Cr metal was 18.02 mg/kg by Portulaca grandiflora with the addition of 10% manure and 90% red mud. Therefore, the results demonstrated that the addition of 10% manure enhanced the capacity of plants to absorb metals.

A compact and stable diagnostic system is established using Raman scattering to measure parameters such as major species concentration and temperature in the combustion flow field. Despite an engine's huge vibration, the prototype works stably and has an uncertainty level below 5%. A standard Hencken burner validates the results. From our perspective, the prototype represents a novel practical application of mature Raman spectroscopy technology, warranting interaction with engineering experts in relevant fields. The background and signal are distinguished with the half-wave plate. The orthogonality and angle between excitation and signal contribute to a good signal-to-noise ratio (SNR). The compactness of the device is fully considered. The device exhibits good resistance to adverse environments. The system's temperature is minimally affected by external conditions, and it has good vibration resistance features. The temporal resolution of a single pulse of the device is 10 ns. The spatial resolution is 3 mm × 0.2 mm × 0.2 mm with one-dimension measurement available. [ABSTRACT FROM AUTHOR]

In the context of the worldwide attention on climate change, examining how land use relates to the carbon sink functions of regions is essential. This research innovatively utilizes the 2000–2020 land use data of Changde City, integrating the PLUS and InVEST models to analyze spatiotemporal changes and predict scenarios. It also combines the parameter geodetector and multiscale geographically weighted regression model to dissect driving factor distributions and mechanisms, capture interactions and multiscale impacts, uncover underlying laws, pioneer new paths for similar studies, and support regional ecological sustainability. The results show that from 2000–2020, forest and arable land areas declined while construction land expanded, leading to a yij1,172,200-ton carbon storage reduction in Changde City. Carbon storage decreased under natural development and arable land protection scenarios but increased in the ecological scenario. The main drivers of carbon storage in Changde City are the DEM, slope, and annual average temperature, with their interactions enhancing spatial heterogeneity. Human activities, especially in mountains and urbanizing regions, negatively impact carbon storage. This study aids in optimizing land resource allocation, improving land use efficiency, and promoting coordinated and sustainable development in Changde City's ecological, economic, and social systems. [ABSTRACT FROM AUTHOR]

The increasing amount of annual red mud generation is becoming a global concern because of the environmental problems caused by its high metal content, alkalinity, and salinity. To manage red mud deposits, various green technologies have been implemented, such as phytoremediation and bioremediation. Accordingly, this study aimed to assess the morphological features of indigenous microbes in bauxite residue disposal areas (BRDA) in Indonesia. Using Gram staining method and microscopic analysis, indigenous microbial species were characterised based on morphological features such as colony profile, colour, size, margin, elevation and cell shape. As many as 10 isolates of indigenous microbes were successfully identified. All isolated were Gram positive and mostly white. The shape of colonies varied from irregular, circular, and filamentous with flat elevation, whereas the cell shape was identified as rod-shape and round-shape. Based on the similarity of the morphological characteristics of these microbes, there are five suspected genus, i.e., Micrococcus, Microbacterium, Bacillus, Cylindrogloea, Eubacterium, and Staphylococcus.

The erosion and sedimentation of bank slopes are important factors affecting the safety of wharf operations. The essence of bank slope monitoring is to identify the water–soil interface. This paper proposes a model for soil-and-water interface identification and monitoring equipment buried on the bank slope of the wharf, based on the difference in thermodynamic heat transfer between water and soil media, and presents the results of multi-condition numerical simulation. The comparison between numerical simulation results and indoor experimental results shows that the overall patterns are consistent, with an error of less than 11.4%, which is lower than the deviation between theoretical calculation results and indoor experiments. Based on the accuracy of the numerical calculation results, the temperature rise and propagation characteristics of linear heat sources made of iron and PVC in eight types of cohesive soils and six types of non-cohesive soils were studied. The results indicate that there are significant differences in the temperature distribution of linear heat sources made of iron and PVC in both water and soil media. The monitoring equipment model based on the difference in heat transfer between water and soil can be applied in practical engineering. This provides a foundation for the design and application of subsequent monitoring equipment. [ABSTRACT FROM AUTHOR]

This study investigated the effects of curcumin nanoparticles on the flesh quality of largemouth bass on a high-carbohydrate diet. A total of 180 fish (11.01 ± 0.02 g) were fed three semi-purified diets: the Control group (LC) were supplemented with standard carbohydrate (10%), the experimental group (HC) were supplemented with 15% carbohydrate, and the experimental group were supplemented with 0.2% nano-curcumin added to 15% carbohydrate (HCN) for 6 weeks. Results showed that a* value, taurine, valine, isoleucine, histidine, cystine, fatty acids (C17:0 and C20:2n6), MDA (malondialdehyde) content, and SOD (Superoxide dismutase) activity were significantly elevated (p < 0.05) in HC. Muscle fibers showed significant increases in horizontal diameter, longitudinal diameter, and cross-sectional area (p < 0.05), as well as up-regulated expression levels of the MRFS (myogenic regulatory factor) family gene and MSTN (myostatin) (p < 0.05), and a significant decrease in C16:1n7 in HC (p < 0.05). Importantly, the HCN group enhanced the muscle quality of largemouth bass by elevating the L* value, valine, isoleucine, arginine and cystine, C20:2n6, decreasing (p < 0.05) refrigeration loss, chewability, firmness and hardness, then MDA content and SOD activity, and downregulating (p < 0.05) MSTN and MRFS family gene expression levels to improve largemouth bass muscle quality. [ABSTRACT FROM AUTHOR]

Nano-plastics (NPs) have emerged as a pervasive global contaminant, posing significant threats to carnivorous fish, in recent years. The accumulation of polystyrene nano-plastics (PS-NPs) can cause endoplasmic reticulum (ER) stress. However, the concurrent impacts of PS-NPs on lipid metabolism and ER stress in largemouth bass have not been sufficiently investigated. To study this gap, we established a largemouth bass model exposed to PS-NPs in a culture environment. The exposure experiment focused on 100 μg/L PS-NPs (100 nm). Transcriptomics analysis revealed a significant enrichment of differentially expressed genes involved in a lipid metabolism pathway and ER process. The levels of biochemical parameters associated with lipid metabolism, including high-density lipoprotein cholesterol, total cholesterol, triglyceride, and low-density lipoprotein cholesterol, demonstrated that exposure to PS-NPs for nineteen days had an impact on lipid metabolism. Additionally, the expression levels of genes associated with fatty acid biosynthesis and ER stress exhibited a significant increase following exposure to PS-NPs for nineteen days, whereas these changes were not significant after a seven-day exposure period. The ER stress induced by PS-NPs exhibited a positive correlation with lipid metabolism disorder and the magnitude of damage caused by prolonged exposure to PS-NPs in largemouth bass. The present study provides novel insights into the health threats encountered by largemouth bass when exposed to NPs. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical effect of concentrated growth factor (CGF) applied in guided bone regeneration (GBR) for severe bone deficiency in the anterior maxilla. Methods Forty patients with bone defects in the anterior maxilla were chosen to be treated with GBR, 20 patients were treated with CGF applied in GBR as the observation group, and the other 20 patients were treated only with GBR as the control group. The evaluation of wound healing was performed after the operation, and bone augmentation was evaluated half a year after the operation. Results The first-stage healing rate of soft tissue wounds in the observation group was 100% and 75% in the control group, and the primary healing rate in the observation group was better than that in the control group (P=0.017). The changes in bone width of the observation group were （3.70 ± 0.28） mm, and those of the control group were （2.96 ± 0.16） mm. The bone augmentation in the observation group was higher than that in the control group (P=0.000). Conclusion CGF applied in GBR has a good effect on bone augmentation for severe bone deficiency in the anterior maxilla.