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The leaf area index (LAI) is an important growth indicator used to assess the health status and growth of citrus trees. Although LAI estimation based on unmanned aerial vehicle (UAV) platforms has been widely used for field crops, mainly focusing on food crops, less research has been reported on the application to fruit trees, especially citrus trees. In addition, most studies have used single-modal data for modeling, but some studies have shown that multi-modal data can be effective in improving experimental results. This study utilizes data collected from a UAV platform, including RGB images and point cloud data, to construct single-modal regression models named VoVNet (using RGB data) and PCNet (using point cloud data), as well as a multi-modal regression model called VPNet (using both RGB data and point cloud data). The LAI of citrus trees was estimated using deep neural networks, and the results of two experimental hyperparameters (loss function and learning rate) were compared under different parameters. The results of the study showed that VoVNet had Mean Squared Error (MSE), Mean Absolute Error (MAE), and R-Squared (R2) of 0.129, 0.028, and 0.647, respectively. In comparison, PCNet decreased by 0.051 and 0.014 to 0.078 and 0.014 for MAE and MSE, respectively, while R2 increased by 0.168 to 0.815. VPNet decreased by 0% and 42.9% relative to PCNet in terms of MAE and MSE to 0.078 and 0.008, respectively, while R2 increased by 5.6% to 0.861. In addition, the use of loss function L1 gave better results than L2, while a lower learning rate gave better results. It is concluded that the fusion of RGB data and point cloud data collected by the UAV platform for LAI estimation is capable of monitoring citrus trees' growth process, which can help farmers to track the growth condition of citrus trees and improve the efficiency and quality of orchard management. [ABSTRACT FROM AUTHOR]

• Cadmium causes spermiogenic defects at puberty, which differ from that at maturity. • Consumption of C3G restores the declined semen quality caused by Cd. • C3G normalizes histone modification for a smooth exchang of histone-to-protamine. • C3G ameliorates the oxidative system of testes for reducing apoptosis of sperm cells. Cadmium (Cd) is an environmental contaminant found in soil, water, and food, and can cause oxidative stress and male reproductive damage. During puberty, the male reproductive system is very vulnerable to interference, however, the dysregulation of Cd on spermatogenesis in this period is ambiguous. The anthocyanin cyanidin-3- O -glucoside (C3G) is phytochemical rich in plants and fruits and has been shown to have remarkable anti-oxidant activity, making it an ideal nutrient for nutritional intervention. By modeling Cd-induced damage in male pubertal mice and feeding with C3G, we demonstrated that the C3G could rescue the amount and activity of sperm predominantly. Furthermore, C3G showed partial resistance to Cd-induced histone modification during spermiogenesis and prevented oxidative damage of the DNA in the sperm nucleus. Additionally, C3G mitigated the oxidative stress of testis to achieve the level coinciding with the control group. Meanwhile, Cd-induced mitochondrial apoptosis of sperm cells was reduced significantly via the MAPK signaling pathway in the presence of C3G. Collectively, our findings can offer a potential intervention for combating Cd-induced reproductive damage during puberty by taking anthocyanin as a dietary supplement. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Clinafloxacin-azole conjugates were designed as novel anti-TB agents. • Conjugates were tested against M. tuberculosis and indicator bacteria strains. • TM2l exhibited good drug-likeness. • Modifications to the 7-pyrrolidine amino group increased drug lipophilicity. • Highly active anti-TB conjugates showed selectivity for M. tuberculosis. Abstract Based on the advantages of azole molecules and fluoroquinolone drugs, we designed and synthesized 34 clinafloxacin-azole conjugates using fragment-based drug design and drug combination principles. The in vitro activities of the synthesized conjugates against Mycobacterium tuberculosis (H37Rv), Hela cell as well as Gram-positive and Gram-negative bacteria were assayed. The bio assay results revealed that most of the target molecules had anti-tuberculosis (anti-TB) activity, of which 14 compounds had very strong anti-TB activity [minimum inhibitory concentration (MIC) < 2 μM]. In addition, the compounds with strong activity towards H37Rv had weak activity towards Gram-negative and Gram-positive bacteria, showing obvious selectivity towards H37Rv. Predicted toxicity data indicated that 27 molecules were less toxic or equivalent to that of the original drug (clinafloxacin). Especially, it is demonstrated that compound TM2l exhibited the strongest anti-TB activity (MIC = 0.29 μM), low antibacterial activity, negligible toxicity, and good drug-likeness values, which can be considered as an ideal lead molecule for future optimization. [ABSTRACT FROM AUTHOR]

Random network coding (RNC) has emerged as a promising technology. In this paper, we seek to answer the question that how RNC benefits cellular systems. A novel RNC-based space-time code (STC) scheme is proposed for the data transmission in MIMO system. In this scheme, RNC is integrated with the STC design for MIMO system. And then, the improved diversity order and multiplexing gain of the RNC-based STC scheme are analyzed and derived. This RNC-based STC scheme can also have benefit of RNC on some practical applications. After that, a general RNC-based STC protocol which describes the data transmission flow in practical system is designed for MIMO transmission. Finally, the performance of RNC-based STC scheme is evaluated through both link-level and system-level simulations. The simulation results show that RNC can provide extra diversity gain, multiplexing gain, or reduce the decoding complexity, and improve the bandwidth efficiency and user fairness in cellular system with MIMO. [ABSTRACT FROM AUTHOR]

A rapid and sensitive detection method for phthalate esters (PAEs) was developed by using an optical fiber immunosensor based on indirect competitive immunoassay. This sensor was constructed by covalent binding of coating antigen on the surface of optical fiber, and the inhibition signal of PAEs to immune reaction between coating antigen and fluorescent-labeled antibody was detected by avalanche photodiode. The response signal showed a negative correlation with the logarithm of PAEs concentration in the range of 0.01–100 μg/L, and the limits of detection (LODs) of eight PAEs ranged from 19 to 51 ng/L. The fluorescent-labeled antibody displayed broad cross-reactivity in the range of 16.63%–71.94% for the other seven PAEs (100% for dimethyl phthalate). The average recoveries of PAEs at the spiked levels of 5, 10 and 100 μg/kg ranged from 61.5% to 106.7% with relative standard deviation (RSD) values below 13.41%, and these results were consistent with those obtained by gas chromatography-mass spectrometry (GC–MS). The optical fiber immunosensor has good regeneration performance, reproducibility and stability, and displays wide linear range, high sensitivity, simple sample pretreatment and short detection time for PAEs detection. The new method has been successfully applied to the determination of multiple PAEs in greenhouse soils. [ABSTRACT FROM AUTHOR]

Natural products derived from fruits have multiple antitumor potential. However, very few have been developed for clinical therapy, due to the limited efficiency or insufficient study of their mechanism. Since lung cancer is the most common cancer in the world, there is still need to explore novel compounds but their molecular mechanisms remain elusive. In this study, a new compound Final-2 was synthesized. Final-2 exhibited antitumor activity in A549 cells by promoting apoptosis and blocking autophagy. Moreover, Final-2 significantly induced G 0 /G 1 cycle arrest and inhibited cell malignancy. Intracellular molecular targets investigation showed that Final-2 inhibited the Gluts, which resulted in downregulation of glucose metabolism and the oncogene c-Myc and Kras expression in vitro. However, according the autophagy inhibitor CQ and Kras inhibitors test, low concentration of Final-2 showed some controversial effects. In A549 xenograft mice model, 10 mg/kg and 20 mg/kg of Final-2 showed no and partial tumor inhibition, respectively. Moreover, a high dose of Final-2 induced serious liver necrosis. Therefore, the results indicated that even though Final-2 was efficient in suppressing the cancer cell growth in vitro, it failed to inhibit tumors in vivo and showed significant liver toxicity, which was its limitation as a potential antitumor drug., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Zearalenone is commonly generated from moldy cereal grain, which is toxic to the development of gametogenesis and embryo in human and animals. The zearalenone-induced reproductive damage is mainly attributed to four mechanisms. Firstly, zearalenone as an oestrogen-like compound binds to estrogen receptor and causes damage to germ cells and testicular structure. Secondly, zearalenone disrupts the blood-testis barrier, and causes the damage to germ cells. Thirdly, zearalenone elevates oxidative stress, which increases the production of lipid peroxides, and results in the damage to the antioxidant defense system. Fourth, zearalenone increases DNA damage and promotes cells apoptosis. In addition, Zearalenone induces inflammatory reactions and leads to the disorders of reproductive hormones. In this study, we systematically introduced the toxic effects of zearalenone on gametogenesis and embryonic development in animals, and focused on the molecular pathways, which providing a basis for further prevention of zearalenone-induced injury., (Copyright © 2018. Published by Elsevier Ltd.)

In accordance with the structural characteristics of thiazolidinedione drugs and highly bioactive tyrosine derivatives, we tentatively designed the l-phenylglycine derivatives TM1 and TM2 based on basic principles of drug design and then synthesized them. The in vitro screening of peroxisome proliferator-activated receptor gamma (PPARγ) activated activity, α-glucosidase inhibitory and dipeptidyl peptidase-4 inhibitory activities showed that the novel molecule M5 had efficient PPAR response element (PPRE) activated activity (PPRE relative activity 105.04% at 10 μg·mL -1 compared with the positive control pioglitazone, with 100% activity). Therefore, M5 was selected as the hit compound from which the TM3 and TM4 series of compounds were further designed and synthesized. Based on the PPRE relative activities of TM3 and TM4, we discovered another new molecule, TM4h, which had the strongest PPRE relative activity (120.42% at 10 μg·mL -1 ). In addition, the concentration-dependent activity of the highly active compounds was determined by assaying their half-maximal effective concentration (EC 50 ) values. The molecular physical parameter calculation and the molecular toxicity prediction were used to theoretically evaluate the lead-likeness and safety of the active compounds. In conclusion, we identified a potential PPARγ lead molecule and developed a tangible strategy for antidiabetic drug development., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To investigate the epidemiology, internal opening location, and risk factors associated with recurrence of anal fistula., Methods: Clinical data of 1783 hospitalized patients admitted for anal fistula treatment to Shanghai Shuguang Hospital from January 2013 to September 2015 were retrospectively analyzed. Fistula passing through anorectal ring or locating above was defined as high anal fistula (n=125). Internal opening location was defined as follows: posterior (5 to 7 o'clock), front(11 to 1 o'clock), left (2 to 4 o'clock) and right (8 to 10 o'clock)., Results: Among 1783 cases, 1526 were male with a median age of 36 years, 257 were female with a median age of 35 years, and the ratio of male to female was 5.9 vs 1.0. In high anal fistula cases, this ratio of male to female was 7.3 vs 1.0. Posterior internal opening accounted for 51.4%(884/1720), while this percentage was 66.4%(83/125) in high anal fistula cases, which was significantly higher than 50.2%(801/1595) in low anal fistula cases(P=0.002). Postoperative recurrence rate was 2.6%(45/1720) and the rates in high anal fistula and low anal fistula were 13.6%(17/125) and 1.8%(28/1595) respectively, with significant difference(P=0.000). Multivariate logistic regression analysis showed that fistula height(OR=5.475, 95%CI:2.230 to 13.445, P=0.000), treatment history(OR=2.671, 95% CI:1.315 to 5.424, P=0.007), seton placement history (OR=4.707, 95%CI:1.675 to 13.232, P=0.003) and concomitant colitis(OR=10.300, 95%CI:1.187 to 89.412, P=0.034) were independent risk factors for anal fistula recurrence. Seton placement history was an independent risk factor for high anal fistula recurrence (OR=6.476, 95%CI:1.116 to 37.589, P=0.037)., Conclusions: Anal fistula occurs in young and middle-aged male patient. Internal opening locates in posterior more commonly, especially in high anal fistula patients. Postoperative recurrence rate of high anal fistula is quite high. Patient with both high anal fistula and seton placement history has significantly high rate of postoperative recurrence.

Artemisinin (ART) and its derivatives artesunate (AS), dihydroartemisinin (DHA) are a group of drugs containing a sesquiterpene lactone used to treat malaria. Previously, AS was shown to not have antibacterial activity but to significantly increase the antibacterial activities of β-lactam antibiotics against E. coli. Herein, molecular docking experiments showed that ART, AS and DHA could dock into AcrB very well, especially DHA and AS; both DHA and AS had the same docking pose. The affinity between AS and AcrB seemed weaker than that of DHA, while the succinate tail of AS, which was like a "bug", could extend in the binding pocket very well. Imitating the parent nucleus of DHA and the succinate tail of AS, twenty-one DHA derivatives 4a-u were designed and synthesized. Among them, seventeen were new compounds. The synergistic effects against E. coli AG100A/pET28a-AcrB showed among the new structures 4k, 4l, 4m, 4n, and 4r exhibited significant synergism with β-lactam antibiotics although they had no direct antibacterial activities themselves. The bacterial growth assay showed that only 4k in combination with ampicillin or cefuroxime could totally inhibit bacterial growth from 0 to 12 h, demonstrating that 4k had the best antibacterial enhancement effect. In conclusion, our results provided a new idea and several candidate compounds for antibacterial activity enhancers against multidrug resistant E. coli.

Objective: Objective Concentrations and proliles of 7 polybrominated diphenyl ethers (PBDEs) compounds in ambient air in Shenzhen city were analyzed, and inhalation exposure amount for local resident was concluded firstly domesticly., Methods: 7 polybrominated diphenyl ethers compounds (PBDEs) (BDE-28, BD-E-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183) in ambient air (including gas phase and particle phase ) were determined by isotope dilution high-resolution gas chromatography/high-resolution double-focusing magnetic mass spectrometer (HRGC/ HRMS) with High volume active air sampler for 11 sampling sites in 6 administrative district in Shenzhen. Furthermore, the inhalation exposure amount for local resident was calculated and concluded using concentration of PBDEs, respiratory rate and gas exchange in the air ratio in Alveolar., Results: The average concentration of PBDEs in atmosphere samples was 29.03 pg/m, ranged from 8.28-168.86 pg/m, the PBDEs pollution level as higher in rain season than that in dry season. The predominant PBDEs congeners measured in the two periods were BDE-47 and BDE-99, accounted for more than 31 and 16 percent of total concentration, respectively. While the specific profile was found in the dry season, the seven monomer distribution proportion tended to be equal, especially BDE-183 accounted for 17 percent of total concentration. Inhalation exposure amount for local adults and children was 4.72 pg/kg and 10.74 pg/kg respectively., Conclusion: he levels of PBDEs in atmosphere in Shenzhen are higher than that in United Kingdom, South Korea, Osaka and Kyoto in Japan, however it is lower than the reported levels of Guangzhou and Beijing. Children's breathing exposure amount is higher than that in adults, this circumstances should be paid more attention. Furthermore, the present study provides the important basic data of PBDEs pollution level in Shenzhen and Inhalation exposure amount for local residents firstly.