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Tree species diversity is vital for maintaining ecosystem functions, yet our ability to map the distribution of tree diversity is limited due to difficulties in traditional field-based approaches. Recent developments in spaceborne remote sensing provide unprecedented opportunities to map and monitor tree diversity more efficiently. Here we built partial least squares regression models using the multispectral surface reflectance acquired by Sentinel-2 satellites and the inventory data from 74 subtropical forest plots to predict canopy tree diversity in a national natural reserve in eastern China. In particular, we evaluated the underappreciated roles of the practical definition of forest canopy and phenological variation in predicting tree diversity by testing three different definitions of canopy trees and comparing models built using satellite imagery of different seasons. Our best models explained 42%–63% variations in observed diversities in cross-validation tests, with higher explanation power for diversity indices that are more sensitive to abundant species. The models built using imageries from early spring and late autumn showed consistently better fits than those built using data from other seasons, highlighting the significant role of transitional phenology in remotely sensing plant diversity. Our results suggested that the cumulative diameter (60%–80%) of the biggest trees is a better way to define the canopy layer than using the subjective fixed-diameter-threshold (5–12 ​cm) or the cumulative basal area (90%–95%) of the biggest trees. Remarkably, these approaches resulted in contrasting diversity maps that call attention to canopy structure in remote sensing of tree diversity. This study demonstrates the potential of mapping and monitoring tree diversity using the Sentinal-2 data in species-rich forests.

Climate warming-induced shifts in spring phenology have substantially affected the structure and function of terrestrial ecosystems and global biogeochemical cycles. Spring phenology is primarily triggered by spring temperature and is also affected by daylength and winter chilling, yet the relative importance of these cues across spatial gradients remains poorly understood. Here, we conducted a manipulative experiment with two daylength and three temperature treatments to investigate spatial differences in the response of ginkgo budburst to temperature and daylength, using twigs collected at three sites across a spatial gradient: a control site at a low latitude and low elevation on Tianmu Mountain (TMlow), a low latitude and high elevation site on Tianmu Mountain (TMhigh), and a high latitude site on Jiufeng mountain (JF). The mechanisms were also tested using in situ phenological observations of ginkgo along latitudes in China. We found that, compared to TMlow individuals, budburst dates occurred 12.6 (JF) and 7.7 (TMhigh) days earlier in high-latitude and high-elevation individuals when exposed to the same temperature and daylength treatments. Importantly, daylength only affected budburst at low latitudes, with long days (16 h) advancing budburst in low-latitude individuals by, on average, 8.1 days relative to short-day (8 h) conditions. This advance was most pronounced in low-elevation/latitude individuals (TMlow = 9.6 days; TMhigh = 6.7 days; JF = 1.6 days). In addition, we found that the temperature sensitivity of budburst decreased from 3.4 to 2.4 days °C−1 along latitude and from 3.4 to 2.5 days °C−1 along elevation, respectively. The field phenological observations verified the experimental results. Our findings provide empirical evidence of spatial differences in the relative effects of spring temperature and daylength on ginkgo budburst, which improved our understanding of spatial difference in phenological changes and the responses of terrestrial ecosystem to climate change.

In this work, we extend the works of F. Usta and construct new modified q -Bernstein operators using the second central moment of the q -Bernstein operators defined by G. M. Phillips. The moments and central moment computation formulas and their quantitative properties are discussed. Also, the Korovkin-type approximation theorem of these operators and the Voronovskaja-type asymptotic formula are investigated. Then, two local approximation theorems using Peetre's K -functional and Steklov mean and in terms of modulus of smoothness are obtained. Finally, the rate of convergence by means of modulus of continuity and three different Lipschitz classes for these operators are studied, and some graphs and numerical examples are shown by using Matlab algorithms. [ABSTRACT FROM AUTHOR]

With the development and generalization of endoscopic technology and screening, clinical application of magnetically controlled capsule gastroscopy (MCCG) has been increasing. In recent years, various types of MCCG are used globally. Therefore, establishing relevant guidelines on MCCG is of great significance. The current guidelines containing 23 statements were established based on clinical evidence and expert opinions, mainly focus on aspects including definition and diagnostic accuracy, application population, technical optimization, inspection process, and quality control of MCCG. The level of evidence and strength of recommendations were evaluated. The guidelines are expected to guide the standardized application and scientific innovation of MCCG for the reference of clinicians., (© 2023 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.)

Background/aims: The present study is to evaluate the roles of HBV infection, host factors and their interactions in the development of ultrasound-diagnosed fatty liver in Fujian province of China, a highly HBV endemic area., Methodology: From June 2007 to May 2008, 527 ultrasound-diagnosed fatty liver patients and 1042 controls were ultrasonically diagnosed in this hospital-based case-control study. Their demographic, anthropometric, biochemical, behavioral factors and HBV markers were compared, and factors associated with fatty liver were determined by multivariate logistic regression analysis., Results: Multivariate ORs and 95% confidence intervals (Cls) of fatty liver were 3.96 (2.10-7.48) for HBsAg positivity, 2.97 (1.78-4.94) for HBsAg negativity with antibodies positivity (either anti-HBe or anti-HBc or both), 1.66 (1.10-2.51) for low alcohol consumption, 7.09 (4.28- 11.75) for obesity, 3.19 (1.75-5.81) for reduced high density lipoprotein cholesterol (HDL-C), 2.17 (1.00-4.72) for elevated fasting plasma glucose (FPG), 2.71 (1.72-4.27) for hypertriglyceridemia, 9.19 (4.32-19.57) for hypertension, and 2.89 (1.86-4.48) for hyperuricemia. Furthermore, synergistic interactions on the additive model were observed between HBV infection and obesity, hypertriglyceridemia, reduced HDL-C, and hyperuricemia with regard to the risk of fatty liver., Conclusions: Ultrasound-diagnosed fatty liver in Fujian province of China is closely associated with HBV infection, low alcohol consumption, obesity, and other features of the metabolic syndrome. In addition, HBV infection was synergistic with obesity, hypertriglyceridemia, reduced HDL-C, and hyperuricemia as far as the risk of fatty liver concerned.

Objective: Some researchers considered medium chain fatty acids a group of potential agents in the prevention of obesity for their particular metabolism characters., Methods: In this study, the authors investigated the effects of medium chain fatty acids on body weight gains, food intake, adipose depots and serum lipid profiles. Healthy male Sprague-Dawley rats were fed for 38 days with over-fat diets and oils containing MCFA at different level., Results: Significant decreases of body weight [( 295.2 +/- 29.7) g vs. (324.6 +/- 9.1) g] (P < 0.05), the weight of adipose pads [(5.30 +/- 1.57) g vs. (7.20 +/- 1.74) g](P < 0.05), the level of leptin in serum[(1.61 +/- 0.39) ng/ml vs. (2.04 +/- 0.46) ng/ml] (P < 0.05), the sizes of fat cells but increase of HDL-C [(0.73 +/- 0.12) mmol/L vs. (0.60 +/- 0.06)mmol/L] (P < 0.05) were noted in the group fed MCFA at 0.975 g/kg bw per day as compared with those of the group fed soybean oil., Conclusion: The results suggested the role of MCFA in prevention of obesity and there is no adverse effect on lipid metabolism if the proportion of MCFA to total fat scouce is mild.

Aim: To study the expression and serum level of HBxAg, Fas and FasL in tissues of HCC patients, and to assess the relationship between HBxAg and Fas/FasL system., Methods: Tissues from 50 patients with HCC were tested for the expression of HBxAg, Fas and FasL by S-P immunohistochemistry. Serum levels of sFas/sFasL and HBsAg/HBeAg were measured by ELISA assay. HBV X gene was detected by PCR in serum and confirmed by automatic sequencing. Fifty cases of liver cirrhosis and 30 normal controls were involved in serum analysis., Results: The expression of HBxAg, Fas and FasL in carcinoma tissues was 96 %, 84 % and 98 %, respectively. Staining of HBxAg, Fas and FasL was observed predominately in cytoplasms, no significant difference was found in intensity between HBxAg, Fas and FasL (P>0.05). HBxAg, Fas and FasL might express in the same area of carcinoma tissues and this co-expression could be found in most patients with HCC. The mean levels of sFas in serum from HCC, cirrhosis and normal controls were 762.29 +/- 391.56 microg.L(-1), 835.36 +/- 407.33 microg.L(-1) and 238.27 +/- 135.29 microg.L(-1). The mean levels of sFasL in serum from HCC, cirrhosis and normal controls were 156.36 +/- 9.61 microg.L(-1), 173.63 +/- 18.74 microg.L(-1) and 121.96 +/- 7.83 microg.L(-1). Statistical analysis showed that both sFas and sFasL in HCC and cirrhosis patients were significantly higher than those in normal controls (P<0.01). Serum HBV X gene was found in 32% of HCC patients and 46% of cirrhotic patients. There was no significant relationship between serum level of sFas/sFasL and serum X gene detection (P>0.05). Eight percent of HCC patients with negative HBsAg and HBeAg in serum might have X gene in serum and HBxAg expression in carcinoma tissues., Conclusion: Our data suggest that HBxAg and Fas/FasL system plays an important role in the development of human HCC. Expression of HBxAg can leads to expression of Fas/FasL system which and reverse apoptosis of hepatocellular carcinoma induced by FasL.

Aim: To study the expression of IGF-1 and IGF-1R and its intervention by interleukin-10 in the course of experimental hepatic fibrosis., Methods: Hepatic fibrosis was induced in rats by carbon tetrachloride intoxication and liver specimens were taken from the rats administered CCl4 with or without IL-10 treatment and the animals of the control group. Immunoreactivities for insulin-like growth factor-1 (IGF-1) and IGF-1 receptor(IGF-1R) were demonstrated by immunohistochemistry, and their intensities were evaluated in different animal groups., Results: The positive levels for IGF-1 and IGF-1R were increased with the development of hepatic fibrosis, with the positive signals localized in cytoplasm and/or at the plasmic membrane of hepatocytes. The positive signals of IGF-1 and IGF-1R were observed more frequently (P<0.01) in the CCl4-treated group (92.0 % and 90.0 %) compared to those in the control group. The positive signals decreased significantly (P<0.05) in IL-10-treated group. The responses in IGF-1 and IGF-1R expression correlated with the time of IL-10 treatment., Conclusion: The expression of IGF-1 and IGF-1R immunoreactivities in liver tissue seems to be up-regulated during development of hepatic fibrosis induced by CCl(4), and exogenic IL-10 inhibits the responses.

Aim: To evaluate the potential role of Nimesulide, a selective COX-2 inhibitor, in proliferation and apoptosis of gastric adenocarcinoma cells SGC7901., Methods: Cell counts and MTT assay were used to quantify the influence of Nimesulide in the proliferation of SGC7901 cells. Transmission electron microscopy and flow cytometry were used to observe the induction of Nimesulide the apoptosis of SGC7901 cells and influence in the distribution of cell cycle. The expression of P27(kip1) protein was observed by immunocytochemical staining., Results: SGC-7901 Cells treated with Nimesulide at various concentrations exhibited a profound dose- and time-dependent reduction in the proliferation rate over the 72 h test period. The highest survival rate of the cells was 78.7 %, but the lowest being 22.7 %. Nimesulide induced apoptosis of the cells in a dose-dependent and non-linear manner and increased the proportion of cells in the G(0)/G(1) phase and decreased the proportion in the S and G(2)/M phase of the cell cycle. Meanwhile, Nimesulide could up-regulate the expression of P27(kip1) protein., Conclusion: The induction of apoptosis and cell cycle arrest are both anti-proliferative responses that likely contribute to the antineoplastic action of nimesulide on SGC-7901 cells. The up-regulation of P27(kip1) gene may contribute to the accumulation of these cells in the G(0)/G(1) phase following treatment with Nimesulide. Selective COX-2 inhibitor may be a new channel of the chemoprevention and chemotherapy for gastric carcinoma.