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[Figure: see text].

The battle against tobacco usage is being fought on all fronts. On December 19, 2019, a measure to raise the minimum age to buy tobacco products to 21 from 18 was passed by the United States Congress and signed by President Donald Trump. This instated banning the sale of all tobacco products and electronic cigarettes to anyone in the US under the age of 21. This follows the raising of the age to buy tobacco in California to 21 in 2016. According to the California Tobacco Control Program: in 2016, roughly 10% of high-school students were smoking cigarettes, but by 2018, only 2%. The percentage of retailers selling tobacco to underaged youth dropped dramatically. These data show that the CA Tobacco 21 law was effective in decreasing the obtainability and usage of tobacco by youth. We expect that US Tobacco 21 will be similarly effective in reducing tobacco use by youth leading to less tobacco addiction in the US.

Accurate mangrove biomass measurement is necessary for the management and protection of mangrove ecosystems. Sonneratia apetala was the first high-quality mangrove species to be introduced for mangrove restoration in China. Compared with other mangrove species, Sonneratia apetala has higher productivity and can store large amounts of carbon in its living biomass. However, accurate depiction of the single-wood canopy of Sonneratia apetala is challenging because of its high clumping density and intricate canopy structure. While traditional satellite remote sensing focuses on regional or larger-scale monitoring needs, the newly emerged Unmanned Aerial Vehicle (UAV) remote sensing has significant advantages for monitoring mangroves at finer scales. However, few studies have used UAV data for mangrove biomass analyses. In this study, we successfully used consumer-grade UAV data to estimate the height and aboveground biomass (AGB) of Sonneratia apetala on Qi'ao Island, Zhuhai, Guangdong Province. We used a variable window filter algorithm to detect the treetops. Individual tree canopy segmentation was performed using the seed region-growing algorithm. Additionally, we constructed a regression equation for height (H) and diameter at breast height (DBH) of Sonneratia apetala in the study area and optimized the traditional allometric equation. Finally, mangrove AGB was estimated at the tree level using the optimized allometric equation, and the results indicated that the AGB of Sonneratia apetala could be accurately extracted using UAV images. The accuracy of the tree delineation was 67%, the correlation between H and DBH was DBH = 2.2726H-6.4415, and the correlation coefficient R2 was 0.8713. The aboveground mass of a single wood of Sonneratia apetala in the study area ranged from 29.60 to 388.44 kg, with a mean value of 145.72 kg and a total aboveground mass of 368.97 t. Partial spatial clustering was observed in the distribution of the aboveground mass of Sonneratia apetala in the study area, with a Moran's I index value of 0.594. The aboveground mass of Sonneratia apetala at the edge of the area and in the window part of the area was found to be smaller, mainly for two possible reasons. First, the natural death of Sonneratia apetala in part of the study area created a window, but its surrounding seedlings were still in the biomass accumulation stage. Second, the aboveground mass of Sonneratia apetala at the edges of the study area is often lost due to its vulnerable nature and anthropogenic factors. The average number of Sonneratia apetala in each quadrat was 6.3 and the AGB in the study area ranged from 2.99 to 247.24 t/hm2, with a mean value of 92.14 t/hm2. The estimated AGB based on UAV data was consistently lower than that generated from field data. The methods described in this study offer the possibility of easily repeatable, low-cost UAV surveys, providing a faster and more economical approach for monitoring mangrove forests than traditional ground surveys. These results may assist in decision-making regarding ecological monitoring, resource use, mangrove introduction, and scientific advancement of mangroves in China.

Excessive glucocorticoid (GC) production in adipose tissue promotes the development of visceral obesity and metabolic syndrome (MS). 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) is critical for controlling intracellular GC production, and this process is tightly regulated by hexose-6-phosphate dehydrogenase (H6PDH). To better understand the integrated molecular physiological effects of adipose H6PDH, we created a tissue-specific knockout of the H6PDH gene mouse model in adipocytes (adipocyte-specific conditional knockout of H6PDH (H6PDHAcKO) mice). H6PDHAcKO mice exhibited almost complete absence of H6PDH expression and decreased intra-adipose corticosterone production with a reduction in 11β-HSD1 activity in adipose tissue. These mice also had decreased abdominal fat mass, which was paralleled by decreased adipose lipogenic acetyl-CoA carboxylase (ACC) and ATP-citrate lyase (ACL) gene expression and reduction in their transcription factor C/EBPα mRNA levels. Moreover, H6PDHAcKO mice also had reduced fasting blood glucose levels, increased glucose tolerance, and increased insulin sensitivity. In addition, plasma free fatty acid (FFA) levels were decreased with a concomitant decrease in the expression of lipase adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) in adipose tissue. These results indicate that inactivation of adipocyte H6PDH expression is sufficient to cause intra-adipose GC inactivation that leads to a favorable pattern of metabolic phenotypes. These data suggest that H6PDHAcKO mice may provide a good model for studying the potential contributions of fat-specific H6PDH inhibition to improve the metabolic phenotype in vivo. Our study suggests that suppression or inactivation of H6PDH expression in adipocytes could be an effective intervention for treating obesity and diabetes.

In order to study the influence of surface circumferential crack defects on pipelines， based on the extended finite element method(XFEM)， a numerical simulation study was carried out on the crack propagation law of the X60 steel pipeline with circumferential circular surface cracks using the finite element software ABAQUS. Furthermore，the effects of crack location，internal pressure and initial crack size on the circumferential propagation of surface crack were discussed， and the maximum stress of the pipeline with cracked defects only under the action of internal pressure as well as the tensile displacement of the pipeline when the crack expands and penetrates the pipeline wall were analyzed.Results showed that the maximum stress on the pipeline was at the tip of the crack， and the stress there decreased after the crack expanded.When only under the action of internal pressure， the maximum stress of the pipe with circumferential cracks increased linearly with the rising of internal pressure， and the initial size and location of the crack had little effect on the maximum stress of the pipeline with circumferential cracks. Under the effect of axial displacement， the initial size of the crack had a significant influence on the displacement when the crack propagated. The axial displacement of the pipeline when the crack expands and penetrates the pipeline wall decreased rapidly with the rising of the crack size. When the crack size was in a certain range， the axial displacement of the pipeline when the inner wall crack expands and penetrates the pipe wall was smaller than the outer wall crack， which indicated that the crack on the inner wall was more dangerous. After the cracks increased to a certain size， the outer wall cracks became more dangerous.