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Rice is a globally important food crop, and it is crucial to accurately and conveniently obtain information on rice fields, understand their spatial patterns, and grasp their dynamic changes to address food security challenges. In this study, Chongqing's Yongchuan District was selected as the research area. By utilizing UAVs (Unmanned Aerial Vehicles) to collect multi-spectral remote sensing data during three seasons, the phenological characteristics of rice fields were analyzed using the NDVI (Normalized Difference Vegetation Index). Based on Sentinel data with a resolution of 10 m, the NDVI difference method was used to extract rice fields between 2019 and 2023. Furthermore, the reasons for changes in rice fields over the five years were also analyzed. First, a simulation model of the rice harvesting period was constructed using data from 32 sampling points through multiple regression analysis. Based on the model, the study area was classified into six categories, and the necessary data for each region were identified. Next, the NDVI values for the pre-harvest and post-harvest periods of rice fields, as well as the differences between them, were calculated for various regions. Additionally, every year, 35 samples of rice fields were chosen from high-resolution images provided by Google. The thresholds for extracting rice fields were determined by statistically analyzing the difference in NDVI values within the sample area. By utilizing these thresholds, rice fields corresponding to six harvesting regions were extracted separately. The rice fields extracted from different regions were merged to obtain the rice fields for the study area from 2019 to 2023, and the accuracy of the extraction results was verified. Then, based on five years of rice fields in the study area, we analyzed them from both temporal and spatial perspectives. In the temporal analysis, a transition matrix of rice field changes and the calculation of the rice fields' dynamic degree were utilized to examine the temporal changes. The spatial changes were analyzed by incorporating DEM (Digital Elevation Model) data. Finally, a logistic regression model was employed to investigate the causes of both temporal and spatial changes in the rice fields. The study results indicated the following: (1) The simulation model of the rice harvesting period can quickly and accurately determine the best period of remote sensing images needed to extract rice fields. (2) The confusion matrix shows the effectiveness of the NDVI difference method in extracting rice fields. (3) The total area of rice fields in the study area did not change much each year, but there were still significant spatial adjustments. Over the five years, the spatial distribution of gained rice fields was relatively uniform, while the lost rice fields showed obvious regional differences. In combination with the analysis of altitude, it tended to grow in lower areas. (4) The logistic regression analysis revealed that gained rice fields tended to be found in regions with convenient irrigation, flat terrain, lower altitude, and proximity to residential areas. Conversely, lost rice fields were typically located in areas with inconvenient irrigation, long distance from residential areas, low population, and negative topography. [ABSTRACT FROM AUTHOR]

Recently, the micro-nano bubble (MB) technology has attracted people's attention due to its special advantages. Here, we carried out the technology of combining MB and hydrogen peroxide (MB/H2O2) to achieve efficient degradation of tetracycline wastewater. The effect of MB/H2O2 technology on the degradation efficiency of tetracycline was deeply analysed by investigating the reaction time, H2O2 dosage, pH and MB inlet flow. The results showed that the degradation rate of tetracycline hydrochloride by MB/H2O2 technology can reach 92.43%, which is 9.44 and 3.94 times that of MB and H2O2 alone. Through electron spin resonance (ESR) analysis and free radical quenching experiments, a possible mechanism for MB/H2O2 technology to efficiently degrade TC was proposed. In the MB/H2O2 system, the high temperature and high pressure environment generated when MB ruptures can activate H2O2 to obtain a higher number of active oxygen species. •OH is the main reactive oxygen radical in the process of MB/H2O2 degradation of TC, followed by HO2•/•O2-. In addition, the possible intermediate products of the oxidation TC process were identified by HPLC-MS technology. Under the action of •OH and HO2•/•O2− free radicals, TC molecules undergo demethylation and hydroxylation, ring-opening reactions, isomerization, deethylation, deacylation, deamination and dehydration reactions to generate intermediate products and finally convert them into CO2 and H2O. The development of MB/H2O2 technology can potentially be used to efficiently remove TC substances in the water environment and provide a new method for water purification. [ABSTRACT FROM AUTHOR]

In recent years, driven by Industry 4.0 wave, academic research has focused on the science, engineering, and enabling technologies for intelligent and cyber manufacturing. Using a network science and data mining-based Keyword Co-occurrence Network (KCN) methodology, this work analyzes the trends in data science topics in the manufacturing literature over the past two decades to inform the researchers, educators, industry leaders of knowledge trends in intelligent manufacturing. It studies the evolution of research topics and methods in data science, Internet of Things (IoT), cloud computing, and cyber manufacturing. The KCN methodology is applied to systematically analyze the keywords collected from 84,041 papers published in top-tier manufacturing journals between 2000 and 2020. It is not practically feasible to review this large body of literature through tradition manual approaches like systematic review and scoping review to discover insights. The results of network modeling and data analysis reveal important knowledge components and structure of the intelligent and cyber manufacturing literature, implicit the research interests switch and provide the insights for industry development. This paper maps the high frequency keywords in the recent literature to nine pillars of Industry 4.0 to help manufacturing community identify research and education directions for emerging technologies in intelligent manufacturing. [ABSTRACT FROM AUTHOR]

The composites of g-C3N4 (GCN), MoS2 and loaded g-C3N4/MoS2 (GCN/MoS2) layered materials and Fe doped GCN/MoS2(Fe/GCNM) hybrid materials are prepared by high temperature calcination and hydrothermal method with melamine, ammonium molybdate and thioureas as raw materials. The morphology, size and structure of nanomaterials are characterized by SEM, TEM, FT-IR and DRS. In addition, the photocatalytic activities are evaluated by the concentration ratio C/C0 of MO solution before and after the degradation and optimized the effect of different catalysts and the dosage of composite catalysts. The results show that compared with pure GCN, GCN/MoS2 and Fe/GCNM significantly improve the photodegradation efficiency toward the MO with the C/C0 of 038, 0.23 and 0.17, respectively. In addition, the reaction rate constant (K) of Fe/GC NM is much higher than that of GCN, GCNM and Fe/GCN, which is attributed to the separation of photogenic electron-hole pairs promoted by the synthesis of Fe and MoS2 composted with GCN and improves the catalytic performance. [ABSTRACT FROM AUTHOR]

This brief presents an all-digital low dropout regulator (DLDO) with high regulating resolution and fast transient tracking by combining novel interval-searching algorithm and recover acceleration techniques. By bringing forth an enhanced interval-searching algorithm (ISA) with 9-bit register regulating precision, the output can be stabilized within 8 cycles when the load changes. A recover acceleration (RA) technique is proposed to improve the transient response and stability. The DLDO is fabricated with standard 180-nm CMOS process. The proposed DLDO needs 390 pF output capacitance and can provide as much as 170 mA load current. The measured load regulation is 0.11 mV/mA at 0.9 V output with 160 mA load current range. The maximum current efficiency is up to 99.71%. The two FOMs of 2.03 ps and 0.362 pF are also achieved to illustrate the merits of this design. [ABSTRACT FROM AUTHOR]

Osteoporosis is a severe bone disease characterized by a decrease in the density and structure of bones, with high risks of fractures. Pilose antler peptide (PAP), extracted and purified from deer antlers, can promote regeneration and fracture healing, and strengthen sinews and bone. To determine whether PAP can promote osteoblast development and to elucidate the molecular mechanisms underlying its functions, the present study investigated the effects of PAP on osteoblast proliferation, differentiation and mineralization, and the role of the insulin signaling pathway using MTT assay, alkaline phosphatase activity assay, western blot analysis and reverse transcription-quantitative PCR. The present results suggested that PAP promoted osteoblast proliferation, differentiation and mineralization in vitro via the insulin signaling pathway. The effect of PAP on insulin signaling in osteoblasts may be mediated via the ERK pathway and partially by the PI3K/Akt pathway. The present results indicated that PAP could potentially be developed as an alternative treatment strategy for bone diseases related to diabetes characterized by insulin signaling impairment. [ABSTRACT FROM AUTHOR]

ABSTRACT To improve the flocculation efficiency of coal mine wastewater treatment, we synthesized a cationic flocculant by grafting acrylamide (AM) onto pea starch, and we performed the characterization with elemental analysis, Fourier transform infrared spectrometry, scanning electron microscopy, thermogravimetric analysis, and NMR. The effects of the synthesis conditions were also investigated, and the optimal synthesis parameters of the cationic flocculant were obtained. The mass ratio between pea starch and AM was 0.5 with a reaction temperature of 65 °C. The dosages of ceric ammonium nitrate and 3-chloro-2-hydroxypropyl-trimethylammonium chloride were 0.02 and 0.11 mol/L, respectively. Application experiments for wastewater treatment were carried out consequently, and the optimal dosage of cationic pea starch was 40 mg/L within the pH range 6-8. Compared with other traditional flocculation products, the cationic pea starch showed the best flocculation behavior for coal mine wastewater. Therefore, the cationic pea-starch-grafted AM may be applicable as a novel flocculant in wastewater treatment and has already demonstrated outstanding features. It is bound to replace other traditional flocculants in the future. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43922. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that platelet-rich plasma ( PRP) injections are an effective way to retard intervertebral disc degeneration, but the mechanism of action is unclear. Activated platelets release some growth factors, such as transforming growth factor-β1 ( TGF-β1), which positively modulate the extracellular matrix of nucleus pulposus cells. The purpose of this study was to explore the mechanism underlying the PRP-mediated inhibition of intervertebral disc degeneration. In an in vitro study, we found that the proliferation of nucleus pulposus cells was greatly enhanced with 2.5% PRP treatment. The TGF-β1 concentration was much higher after PRP treatment. PRP administration effectively increased the collagen II, aggrecan and sox-9 mRNA levels and decreased collagen X levels. However, Western blotting demonstrated that specifically inhibiting TGF-β1 signalling could significantly prevent nucleus pulpous cellular expression of Smad2/3 and matrix protein. In a rabbit study, magnetic resonance imaging revealed significant recovery signal intensity in the intervertebral discs of the PRP injection group compared with the very low signal intensity in the control groups. Histologically, the PRP plus inhibitor injection group had significantly lower expression levels of Smad2/3 and collagen II than the PRP group. These results demonstrated that a high TGF-β1 content in the platelets retarded disc degeneration in vitro and in vivo. Inhibiting the TGF-β1/Smad2/3 pathway could prevent this recovery by inactivating Smad2/3 and down-regulating the extracellular matrix. Therefore, the TGF-β1/Smad2/3 pathway might play a critical role in the ability of PRP to retard intervertebral disc degeneration. [ABSTRACT FROM AUTHOR]

Background: Percutaneous vertebroplasty (PVP) and balloon kyphoplasty (BKP) are minimally invasive and effective vertebral augmentation techniques for managing osteoporotic vertebral compression fractures (OVCFs). Recent meta-analyses have compared the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques or conservative treatment; however, the inclusions were not thorough and rigorous enough, and the effects of each technique on the incidence of secondary vertebral fractures remain unclear.Purpose: To perform an updated systematic review and meta-analysis of the studies with more rigorous inclusion criteria on the effects of vertebral augmentation techniques and conservative treatment for OVCF on the incidence of secondary vertebral fractures.Material and Methods: PubMed, MEDLINE, EMBASE, SpringerLink, Web of Science, and the Cochrane Library database were searched for relevant original articles comparing the incidence of secondary vertebral fractures between vertebral augmentation techniques and conservative treatment for patients with OVCFs. Randomized controlled trials (RCTs) and prospective non-randomized controlled trials (NRCTs) were identified. The methodological qualities of the studies were evaluated, relevant data were extracted and recorded, and an appropriate meta-analysis was conducted.Results: A total of 13 articles were included. The pooled results from included studies showed no statistically significant differences in the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques and conservative treatment. Subgroup analysis comparing different study designs, durations of symptoms, follow-up times, races of patients, and techniques were conducted, and no significant differences in the incidence of secondary fractures were identified (P > 0.05). No obvious publication bias was detected by either Begg's test (P = 0.360 > 0.05) or Egger's test (P = 0.373 > 0.05).Conclusion: Despite current thinking in the field that vertebral augmentation procedures may increase the incidence of secondary fractures, we found no differences in the incidence of secondary fractures between vertebral augmentation techniques and conservative treatment for patients with OVCFs. [ABSTRACT FROM AUTHOR]

Bone marrow mesenchymal stem cells (BMSCs) are multipotent stem cells. Finding methods to improve the osteogenic potential of these cells is a key factor in bone tissue engineering. Platelet-rich plasma (PRP) contains powerful growth factors that produce changes in a variety of cell types. The purpose of this study was to explore the effects of PRP on the osteogenic differentiation of BMSCs in vitro. Rabbit BMSCs were harvested and cultured in vitro in control media or in media enhanced with PRP. BMSCs began to attach 12-24 hours after seeding. A MTT assay demonstrated that PRP-induced BMSCs grew rapidly compared with the control group. The PRP group also showed strongly positive staining of alkaline phosphatase and mineralized nodules whereas the control group showed negative staining. However, the alkaline phosphatase activity and the mRNA level of the osteogenic markers (osteocalcin and osteopontin) remained higher in the PRP group. These results confirmed that PRP could enhance the proliferation of BMSCs and effectively promote the osteogenic differentiation of BMSCs in vitro. [ABSTRACT FROM AUTHOR]

Recent studies suggest that cell therapy may be an effective way to repair intervertebral disc degeneration. As a strong immune suppressor, TGF-β1 has been shown to inhibit inflammation respond effectively. The objective of this study was to explore the effects of TGF-β1 during bone marrow mesenchymal stem cells-based therapy for disc degeneration. In vitro assays demonstrated that co-culturing of nucleus pulposus cells with bone marrow mesenchymal stem cells resulted in significantly higher levels of TGF-βl secretion. This increase inhibited IκB phosphorylation and NF-κB activation, detected by western blot analysis. Meanwhile, in a rabbit model, MRI analysis revealed significant recovery of signal intensity in the degenerative discs of rabbits receiving cells transplantation, than receiving cells treated with a TGF-β1 inhibitor or saline. These findings indicated that enhanced TGF-β1 production recovered the degeneration of intervertebral disc. And also immunohistochemical staining detected enhanced collagen II expression in the rabbits treated with cell transplantation. However, the NF-κB positive cells were significantly less than other two control groups. Thus, cell therapy promoted TGF-β1 expression in nucleus pulposus, leading to anti-inflammatory effects via the inhibition of NF-κB, and the amelioration of disc degradation due to increased expression of collagen II and aggrecan in degenerative intervertebral disc. [ABSTRACT FROM AUTHOR]

Background: Craniospinal junction tumors are rare but severe lesions. Surgical stabilization has been established to be an ideal treatment for upper cervical tumor pathology. The purpose of this study was to evaluate the effect of a screw-rod system for occipitocervical fusion.Methods: A total of 24 cases with C1 and C2 cervical tumor underwent occipitocervical fusion with Vertex screw-rod internal fixation from January 2005 to December 2012. Preoperative X-ray and MRI examinations were performed on all patients before the operation, after the operation, and during last follow-up. The JOA score was used to assess neurological function pre and postoperatively.Results: All the patients were followed up for 6 to 42 months with an average of 24 months. The result of X-ray showed that bony fusion was successful in 18 patients at 3 months and 6 patients at 6 months of follow-ups. There was no deterioration of spinal cord injury. The JOA Scores of neurological function increased significantly.Conclusion: The screw-rod system offers strong fixation and good fusion for occipitocervical fusion. It is an effective and reliable method for reconstruction of upper cervical spine tumor. [ABSTRACT FROM AUTHOR]

Under visible light, part of the excited electrons on ZnFe 2 O 4 is captured by O 2 to form · O 2 , and the other part is quickly transferred to TiO 2 through the electron channel formed by the heterojunction, which promotes the separation of electron-hole pairs and formation of free radicals. These free radicals will react with intermediates such as Ti4+NO 2 − adsorbed on TiO 2 to form the final product nitrate. [Display omitted] • Nps ZnFe 2 O 4 /TiO 2 was prepared by a facile hydrothermal method. • The p-n heterojunction ZnFe 2 O 4 /TiO 2 has good photocatalytic activity for the removal of NO x. • The reaction mechanism of photocatalytic NO oxidation was discussed. Titanium dioxide (TiO 2) has become the most promising photocatalyst. It is non-toxic and has a wide range of sources, but its application is limited due to its weak visible light absorption capacity. Compounding with other materials to form heterojunctions has proven to be effective strategies for enabling high photocatalytic performances under visible light. Here, the ZnFe 2 O 4 /TiO 2 composites had been synthesized by a facile hydrothermal method to realize efficient visible light photocatalytic activity of NO x removal. A series of characterizations, such as XRD, ESR, in-situ DRIFTS, etc. , were used to analyze the physical and chemical properties of the photocatalyst, which demonstrated that the composite material had more active sites and a faster electron transfer rate. The optimal sample (12 wt% ZnFe 2 O 4 /TiO 2) had a NO x removal rate of 54 % nearly 11 times higher than that of original TiO 2. On the basis of the above photocatalytic experimental results and characterizations, a possible mechanism or pathway was proposed and illustrated. This work can provide a feasible strategy to prepare TiO 2 -based composite materials with magnetic separation properties to effectively remove NO x. [ABSTRACT FROM AUTHOR]