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Chlorophyll, as a key component of crop leaves for photosynthesis, is one significant indicator for evaluating the photosynthetic efficiency and developmental status of crops. Fractional-order differentiation (FOD) enhances the feature spectral information and reduces the background noise. In this study, we analyzed hyperspectral data from grape leaves of different varieties and fertility periods with FOD to monitor the leaves' chlorophyll content (LCC). Firstly, through sensitive analysis, the fractional-order differential character bands were identified, which was used to construct the typical vegetation index (VI). Then, the grape LCC prediction model was built based on the random forest regression algorithm (RFR). The results showed the following: (1) FOD differential spectra had a higher sensitivity to LCC compared with the original spectra, and the constructed VIs had the best estimation performance at the 1.2th-order differential. (2) The accuracy of the FOD-RFR model was better than that of the conventional integer-order model at different fertility periods, but there were differences in the number of optimal orders. (3) The LCC prediction model for whole fertility periods achieved good prediction at order 1.3, R 2 = 0.778, RMSE = 2.1, and NRMSE = 4.7%. As compared to the original reflectance spectra, R2 improved by 0.173; RMSE and NRMSE decreased, respectively, by 0.699 and 1.5%. This indicates that the combination of FOD and RFR based on hyperspectral data has great potential for the efficient monitoring of grape LCC. It can provide technical support for the rapid quantitative estimation of grape LCC and methodological reference for other physiological and biochemical indicators in hyperspectral monitoring. [ABSTRACT FROM AUTHOR]

Objectives: The micro‐nano structure of 3D‐printed porous titanium (Ti) alloy with excellent performance in avoiding stress shielding and promoting bone tissue differentiation provides a new opportunity for the development of bone implants, but it necessitates higher requirements for bone tissue differentiation and the antibacterial properties of bone implants in clinical practice. Methods: This study investigated the preparation, antimicrobial properties, and osteogenesis‐promoting ability of the 3D printed porous Ti alloy anodic oxidized Ag‐carrying (Ag@3D‐TiO2) scaffolds. The 3D printed porous Ti alloy (3D‐Ti), anodized 3D printed porous Ti alloy (3D‐TiO2), and Ag@3D‐TiO2 scaffolds were synthesized using electron beam melting. The antimicrobial properties of the scaffolds were examined using antibacterial tests and their cytocompatibility was assessed using a cell proliferation assay and acridine orange/ethidium bromide (AO/EB) staining. In vitro cellular assays were used to investigate the effects of the scaffold microstructural features on cell activity, proliferation, and osteogenesis‐related genes and proteins. In vivo animal experiments were used to evaluate the anti‐inflammatory and osteogenesis‐promoting abilities of the scaffolds. Results: The Ag@3D‐TiO2 scaffolds exhibited sustained anti‐microbial activity over time, enhanced cell proliferation, facilitated osteogenic differentiation, and increased extracellular matrix mineralization. In addition, alkaline phosphatase (ALP), collagen type I (COL‐I), and osteocalcin (OCN)‐related genes and proteins were upregulated. In vivo animal implantation experiments, the anti‐inflammatory effect of the Ag@3D‐TiO2 scaffolds were observed using histology, and a large amount of fibrous connective tissue was present around it; the Ag@3D‐TiO2 scaffolds were more bio‐compatible with the surrounding tissues compared with 3D‐Ti and 3D‐TiO2; a large amount of uniformly distributed neoplastic bone tissue existed in their pores, and the chronic systemic toxicity test showed that the 3D‐Ti, 3D‐TiO2, and Ag@3D‐TiO2 scaffolds are biologically safe. Conclusion: The goal of this study was to create a scaffold that exhibits antimicrobial properties and can aid bone growth, making it highly suitable for use in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Objective To investigate the efficacy of microscopic laryngeal surgery, otherwise known as microlaryngoscopy, combined with gastric acid inhibition in the treatment of Reinke's edema. Methods The clinical data of 47 Reinke's edema patients with pharynx reflux preoperatively in our department from April 2016 to December 2019 were collected and retrospectively analyzed. These patients were divided into 2 subgroups according to receiving gastric acid inhibition (n=27) or not (n=20). At the same period, 56 normal subjects (control group) were selected for examination and investigation. The changes of voice function and voice handicap index (VHI) score were compared and analyzed before and in 1, 3 and 6 months after surgery. Results Before operation, fundamental frequency (F0) was significantly lower, and fundamental frequency perturbation (jitter), noise/harmonic ratio (NHR) and amplitude perturbation (shimmer) were obviously higher in the patient group than the normal group (P < 0.05). At 3 and 6 months after operation, F0 was notably higher, while the levels of jitter, shimmer and NHR were remarkably lower in the acid inhibition subgroup than the non-acid inhibition subgroup, and significant differences were observed in above indicators between the former subgroup and the control group (P < 0.05). In 1, 3 and 6 months after operation, F0 was gradually increased and the other 3 voice acoustic indicators were decreased at a certain degree in the both subgroups, with hoarseness gradually reduced. In 1 month after operation, there were no statistical differences in above indicators between the 2 subgroups, but F0 was higher while NHR, jitter and shimmer were lower in the acid inhibition subgroup than the non-acid inhibition subgroup at 3 and 6 months (P < 0.05), though great differences were observed among the 2 subgroups and normal control. The scores of VHI in the patient group before operation were higher than those in the control group (P < 0.05). The patient group had significantly higher scores and total scores in VHI than the control group (P < 0.05). After operation, these scores were decreased gradually after operation, and there were no significant differences between the 2 subgroups at each time point. At 6 months, there was no significant difference among the 2 subgroups and the normal group. Conclusion Surgical treatment is very effective for Reinke's edema, and postoperative gastric acid inhibition therapy can accelerate voice recovery in the patients with pharynx and laryngeal reflux.

To improve the quality of natural seawater to meet the needs of aquaculture production, a large-scale subsurface-flow constructed wetland (HSFCW) was constructed and operated stably for 2 years to understand the reasons for its purification effect on natural seawater. The results of the study showed that the system could maintain a high purification effect on natural seawater during aquaculture; the average removal rates of COD, TSS, TN, NH4+-N, and DON (organic nitrogen) were 22.29%, 49.33%, 36.94%, 10.88%, and 44.08%, respectively. Additionally, the HSFCW could effectively remove harmful algae such as Cyanobacteria; the removal rate of dominant algae species in Cyanobacteria was 90.33–97.93%. The pyrosequencing of 16S ribosomal DNA revealed that Proteobacteria, Nitrospirae, and Chloroflexi were the main and key bacterial phyla in the system. Members of these key gates are regarded as playing important roles in resisting water purification. The study results suggest that the subsurface-flow wetland system can effectively improve seawater quality and reduce the density of harmful algae cells. [ABSTRACT FROM AUTHOR]

Accurate and high-throughput identification of the initial anthesis of soybean varieties is important for the breeding and screening of high-quality soybean cultivars in field trials. The objectives of this study were to identify the initial day of anthesis (IADAS) of soybean varieties based on remote sensing multispectral time-series images acquired by unmanned aerial vehicles (UAVs), and analyze the differences in the initial anthesis of the same soybean varieties between two different climatic regions, Shijiazhuang (SJZ) and Xuzhou (XZ). First, the temporal dynamics of several key crop growth indicators and spectral indices were analyzed to find an effective indicator that favors the identification of IADAS, including leaf area index (LAI), above-ground biomass (AGB), canopy height (CH), normalized-difference vegetation index (NDVI), red edge chlorophyll index (CIred edge), green normalized-difference vegetation index (GNDVI), enhanced vegetation index (EVI), two-band enhanced vegetation index (EVI2) and normalized-difference red-edge index (NDRE). Next, this study compared several functions, like the symmetric gauss function (SGF), asymmetric gauss function (AGF), double logistic function (DLF), and fourier function (FF), for time-series curve fitting, and then estimated the IADAS of soybean varieties with the first-order derivative maximal feature (FDmax) of the CIred edge phenology curves. The relative thresholds of the CIred edge curves were also used to estimate IADAS, in two ways: a single threshold for all of the soybean varieties, and three different relative thresholds for early, middle, and late anthesis varieties, respectively. Finally, this study presented the variations in the IADAS of the same soybean varieties between two different climatic regions and discussed the probable causal factors. The results showed that CIred edge was more suitable for soybean IADAS identification compared with the other investigated indicators because it had no saturation during the whole crop lifespan. Compared with DLF, AGF and FF, SGF provided a better fitting of the CIred edge time-series curves without overfitting problems, although the coefficient of determination (R2) and root mean square error (RMSE) were not the best. The FDmax of the SGF-fitted CIred edge curve (SGF_CIred edge) provided good estimates of the IADAS, with an RMSE and mean average error (MAE) of 3.79 days and 3.00 days, respectively. The SGF-fitted_CIred edge curve can be used to group the soybean varieties into early, middle and late groups. Additionally, the accuracy of the IADAS was improved (RMSE = 3.69 days and MAE = 3.09 days) by using three different relative thresholds (i.e., RT50, RT55, RT60) for the three flowering groups compared to when using a single threshold (RT50). In addition, it was found that the IADAS of the same soybean varieties varied greatly when planted in two different climatic regions due to the genotype–environment interactions. Overall, this study demonstrated that the IADAS of soybean varieties can be identified efficiently and accurately based on UAV remote sensing multispectral time-series data. [ABSTRACT FROM AUTHOR]