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Crop nitrogen is an efficient index for estimating crop yield. Using hyperspectral information to monitor nitrogen in cotton information in real time can help guide cotton cultivation. In this study, we used drip-irrigation cotton in Xinjiang as the research object and employed various nitrogen treatments to explore the correlation between hyperspectral vegetation indexes and leaf nitrogen concentration (LNC) and the canopy nitrogen density (CND) of cotton in different growth periods and interannual. We employed 30 published hyperspectral vegetation indexes obtained through spectral monitoring in 2019 and 2020 to screen for hyperspectral vegetation indexes highly correlated with the nitrogen in cotton indexes. Based on the same group of hyperspectral vegetation indexes, interannual and multi-temporal nitrogen estimation models of cotton were established using three modeling methods: simple multiple linear regression (MLR), partial least-squares regression (PLSR), and support vector regression (SVR). The results showed the following: (1) The correlations between LNC and CND and vegetation index in individual growth periods of cotton were lower than those for the entire growth period. The correlations between hyperspectral vegetation indexes and cotton LNC, CND, leaf area index (LAI), and aboveground biomass (AGB), were significantly different between years and varieties. The relatively stable indexes between vegetation and LNC were TCARI, PRI, CCRI, and SRI-2, and the absolute values of correlation were 0.251~0.387, 0.239~0.422, 0.245~0.387, and 0.357~0.533. In addition, the correlation between CIred-edge and REIlinear and group indicators (CND, AGB, and LAI) was more stable. (2) In the models established by MLR, PLSR, and SVR, the R2 value from the SVR method was higher in the estimation model based on the entire growth period data and LNC and CND. (3) Using the same group of selected hyperspectral vegetation indexes to estimate nitrogen in cotton in different growth stages, the accuracy of the estimation model of canopy nitrogen density (CND) was higher than that of the estimation model for leaf nitrogen concentration. The canopy nitrogen density most stable model was established by MLR at the flowering and boll stages and the full-boll stage with R2 = 0.532~0.665. This study explored the application potential of hyperspectral vegetation indexes to the nitrogen of drip-irrigated cotton, and the results provide a theoretical basis for hyperspectral monitoring for crop nutrients and canopy structure. [ABSTRACT FROM AUTHOR]

• Cardiac complications are associated with poor outcome in COVID-19 patients. • The possible mechanisms of cardiac injury include direct virus invasion, inflammatory storm, hypoxia and instability of coronary plaque. • Special attention should be paid to medicine used in COVID-19 patients, especially those with cardiac side effects. The coronavirus disease-2019 (COVID-19) has become a global pandemic. It has spread to more than 100 countries, and more than 1 million cases have been confirmed. Although coronavirus causes severe respiratory infections in humans, accumulating data have demonstrated cardiac complications and poor outcome in patients with COVID-19. A large percent of patients have underlying cardiovascular disease, and they are at a high risk of developing cardiac complications. The basics of the virus, the clinical manifestations, and the possible mechanisms of cardiac complications in patients with COVID-19 are reviewed. Before an effective vaccine or medicine is available, supportive therapy and identifying patients who are at high risk of cardiac complications are important. [ABSTRACT FROM AUTHOR]

To facilitate the production of tomato products with high bioactivity and improve the utilization of orange‐colored tomatoes, the carotenoids of 11 tomato cultivars were analyzed using high‐performance liquid chromatography with photodiode array detection. Moreover, antioxidant activities were evaluated by four chemical‐based assays, and the influences of thermal treatment on the carotenoids in orange‐colored tomatoes rich in tetra‐cis (7Z, 9Z, 7′Z, and 9′Z)‐lycopene, phytofluene, and phytoene were studied. The nine orange‐colored tomatoes (OT) were divided into two categories: OT‐B, containing five cultivars rich in β‐carotene, and OT‐L, containing the other four cultivars that were abundant in tetra‐cis‐lycopene, phytofluene, and phytoene. The antioxidant activities of OT‐L were higher than those of OT‐B and the SD‐2 cultivar in OT‐L showed similar antioxidant activity to the red tomatoes. During thermal processing, tetra‐cis‐lycopene in SD‐2 decreased about 38% after being exposed to heat for 2 hr at 80 °C, while its content was still higher than other lycopene isomers. Other‐Z‐lycopenes and all‐trans (E)‐lycopene increased from 2.36 ± 0.19 to 14.73 ± 1.16 µg/g fresh weight (FW) and 0.75 ± 0.10 to 5.91 ± 1.02 µg/g FW, respectively. Thus, thermal treatments at lower temperature, such as cold break and pasteurization, were more suitable for processing OT‐L. The results demonstrated that OT‐L could be an excellent raw material to produce tomato products with high bioavailability and bioactivity. The results of this research could provide helpful information for the research and development of tomato products using orange tomatoes and benefit planters and consumers. Practical Application: Some orange tomato cultivars are promising raw materials for tomato products because of their high contents of bioactive tetra‐cis‐lycopene, phytofluene, and phytoene. This study demonstrated the carotenoid components and antioxidant activities of the widely planted orange‐colored tomatoes in China. The obtained knowledge, including the thermal processing effects on the isomerization and degradation of carotenoids in the cultivars, will offer useful information to food processors and benefit the consumers. [ABSTRACT FROM AUTHOR]

Background: As a classic innate immunity pathway, Toll-like receptor 4 (TLR4) signaling has been intensively investigated for its function of pathogen recognition. The receptor is located not only on immune cells but also on sensory neurons and spinal glia. Recent studies revealed the involvement of neuronal TLR4 in different types of pain. However, the specific role of TLR4 signaling in the pain symptom of endometriosis (EM) remains obscure.Methods: The rat endometriosis model was established by transplanting uterine horn tissue into gastrocnemius. Western blotting and/or immunofluorescent staining were applied to detect high mobility group box 1 (HMGB1), TLR4, myeloid differentiation factor-88 adaptor protein (MyD88), and nuclear factor kappa-B-p65 (NF-κB-p65) expression, as well as the activation of astrocyte and microglia. The antagonist of TLR4 (LPS-RS-Ultra, LRU) and MyD88 homodimerization inhibitory peptide (MIP) were intrathecally administrated to assess the behavioral effects of blocking TLR4 signaling on endometriosis-related pain.Results: Mechanical hyperalgesia was observed at the graft site, while HMGB1 was upregulated in the implanted uterine tissue, dorsal root ganglion (DRG), and spinal dorsal horn (SDH). Compared with sham group, upregulated TLR4, MyD88, and phosphorylated NF-κB-p65 were detected in the DRG and SDH in EM rats. The activation of astrocytes and microglia in the SDH was also confirmed in EM rats. Intrathecal application of LRU and MIP alleviated mechanical pain on the graft site of EM rats, with decreased phosphorylation of NF-κB-p65 in the DRG and reduced activation of glia in the SDH.Conclusions: HMGB1-TLR4-MyD88 signaling pathway in the DRG and SDH may involve in endometriosis-related hyperpathia. Blockade of TLR4 and MyD88 might serve as a potential treatment for pain in endometriosis. [ABSTRACT FROM AUTHOR]

Surface fluorinated TiO2 has received extensive attention in recent years due to the improved photocatalytic reactivity compared with that of pure TiO2. However, the synergy of surface fluorine (FS) and oxygen vacancy (VO) is not clear and needs further study. Here we systematically studied the effect of FS, VO and acidic sites of TiO2 nanosheets on the selective photocatalytic oxidation of benzylamine to imine. The photocatalytic activity first increased and then decreased as the content of FS decreased and VO increased. The photocatalytic activity reached a summit with the imine yield of 92.1% over TiO2-B-6 h, which is mainly due to the synergy between FS and adjacent VO, forming the frustrated Lewis pair that boosts the activation of O2. The varied contents of FS and VO not only cause an evident change in the amount of acidic sites, but also affect the band structure and separation efficiency of charge carriers. The experimental and calculation results demonstrate that the coexistence of FS and VO boosted the separation efficiency, density and mobility of photogenerated charge carriers, resulting in the improved photocatalytic activity. The improved photocatalytic activity can be attributed to the combined effects of FS, VO and acidic sites. This work provides a strategy for the explicit regulation of surface species on TiO2 nanosheets for improved photocatalytic activity. [ABSTRACT FROM AUTHOR]