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Amorphous Si3N4 and SiBN monoliths without sintering additives are successfully prepared by high‐pressure–low‐temperature (HPLT) sintering using the single‐source‐precursor‐derived amorphous Si3N4 and SiBN powders as raw materials. The microstructural evolution and crystallization behavior of the as‐prepared samples are investigated using scanning electron and transmission electron microscopy and X‐ray powder diffraction, respectively. The results show that the incorporation of boron in the Si–N network enhances the crystallization temperature up to 1200 °C. The Vickers' hardness of the HPLT‐sintered Si3N4 sample amounts ≈11.6 GPa whether prepared at 1000 or 1200 °C, while the maximum hardness of the SiBN sample is up to 16.3 GPa. The fracture toughness of amorphous Si3N4 and SiBN5 samples is almost identical (around 2.5 MPa m1/2) whether prepared at 1000 or 1200 °C, and SiBN2 and SiBN5 samples show an improved fracture toughness. In addition, the oxidation resistance of the as‐prepared samples is investigated at temperatures up to 1000 °C. A comparison between amorphous Si3N4 and SiBN monoliths demonstrates a positive effect of the presence of boron on their oxidation resistance. [ABSTRACT FROM AUTHOR]

BACKGROUND: There is currently an increase in the use of new types of fertilizers in modern agriculture. Studies have shown that amino acid fertilizers can improve crop yield and quality. However, their effects on crop rhizosphere ecology and their ecological impacts on crop yield are largely unknown. This study evaluated the effects of a water‐soluble amino acid fertilizer (WAAF) on tomatoes and its ecological effects on rhizosphere bacterial communities using greenhouse pot experiments. RESULTS: The results showed that WAAF could promote the growth of tomatoes and improve the quality of fruits more effectively than water‐soluble chemical fertilizer controls. Interestingly, WAAF showed a different regulating pattern on root exudates and increased the secretion of 17 major water‐soluble root exudates, including hexadecanoic acid and 3‐hydroxy‐γ‐butyrolactone. Water‐soluble amino acid fertilizer also affected noticeably the composition, abundance, and beta‐diversity of rhizosphere bacterial communities, and strengthened the potential relationships between community members. Water‐soluble amino acid fertilizer showed a significant selective enrichment ability and recruited some members of the genera such as Cupriavidus, Ralstonia, Chitinophaga, Gemmatimonas, Mitsuaria, Mucilaginibacter, Paracoccus, Sphingopyxis, and Variovorax. Network analysis and functional prediction implied that, besides fertilizer effects, the recruiting of beneficial microbes involved in chemotaxis and biofilm formation was also a considerable factor in tomato yield and quality improvement. CONCLUSION: Our study revealed ecological and recruiting effects of WAAF on rhizosphere microbes and potentially beneficial microbiota, and provided a basis for the amino acid fertilizer regulation of rhizosphere ecology to improve soil health and further improve crop yield and quality. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The sustainable development of resource‐based cities is vital to China's high‐quality development. Based on the support‐pressure framework, this study simplifies the city system into an economy–society subsystem (ESS) and a resource–environment subsystem (RES), and measures the economy social developmental level (ESDL) and resource environmental carrying capacity (RECC) of China's 116 resource‐based cities using the improved entropy‐TOPSIS model. Then, it applies the coupling coordination degree (CCD) and relative development models to explore their coupling coordination relationships and relative developmental types. The results are as follows. (1) The ESDL and RECC of China's resource‐based cities have improved significantly, and there is a large divergence between cities in different regions, development stages, and dominant resource types. (2) The CCD between the ESDL and RECC of China's resource‐based cities is still not ideal, and no city qualifies for the high coordination category. (3) Overall, the RECC lags behind the ESDL, and the cities with a lagging ESDL are concentrated in the western and northeastern regions. Based on these conclusions, three specific suggestions are put forth. This study may provide a scientific reference for the Chinese government to formulate a sustainable development plan for resource‐based cities. Integr Environ Assess Manag 2022;18:770–783. © 2021 SETAC Key Points: Based on the support‐pressure framework, we constructed a comprehensive evaluation index system of the urban economy social developmental level (ESDL) and resource environmental carrying capacity (RECC).We measured the ESDL and RECC in 2013 and 2018 of China's 116 resource‐based cities using the improved entropy‐TOPSIS model, and explored their coupling coordination relationships and relative developmental types.Significant improvement occurred in both subsystems of resource‐based cities in China in 2013–2018; moreover, transformation performance of different resource‐based cities is diverse, no resource‐based city meets the criteria for the high coordination category, and the RECC overall lags behind the ESDL.We proposed three recommendations for the transformation of Chinese resource‐based cities: strengthen the classification guidance, summarize the "Chinese transformation mode" as soon as possible, and cultivate new economic growth poles. [ABSTRACT FROM AUTHOR]

Background: Obesity is a major risk factor for endometrial cancer. Obesity, particularly central obesity, is considered as a systemic inflammatory condition and is related strongly to insulin resistance. C-reactive protein (CRP) is the most recognized biologic marker of chronic systematic inflammation, and it is conceivable that the CRP gene may work together with obesity in the development of endometrial cancer.Methods: On the basis of a population-based case-control study in a Chinese population, the authors obtained obesity measurements and data on 6 CRP single-nucleotide polymorphisms (SNPs) from 1046 patients with newly diagnosed endometrial cancer (cases) and from 1035 age frequency-matched controls. The association of the CRP SNPs with endometrial cancer risk and their modification on the association between obesity and endometrial cancer risk were evaluated.Results: Although CRP SNPs alone were not associated with endometrial cancer, the associations of endometrial cancer with central obesity, measured as the waist-to-hip ratio (WHR) and the waist circumference, seemed to be stronger in women who were homozygous for the major allele of reference SNP (rs)1130864 (cytidine [C]/C) than in women who had the C/thymidine (T) and T/T genotypes (interaction test: P = .013 for WHR; P = .083 for waist circumference). When the women were stratified further by menopausal status, the observed interactions persisted mainly in premenopausal women (interaction test: P < .001 for WHR; P = .002 for waist circumference).Conclusions: The current results suggested that, in the Chinese population that was studied, obesity-related insulin resistance and proinflammatory effects may play an important role in endometrial cancer risk, and these effects were modified significantly by the CRP SNP rs1130864. [ABSTRACT FROM AUTHOR]

Purpose: Biliary tract cancer is an uncommon malignancy with a poor survival rate. We evaluated p16 gene alteration as a prognostic marker for this disease., Experimental Design: We studied p16 gene alterations by sequencing, methylation, and loss of heterozygosity of chromosome 9p in 118 biliary tract carcinomas, including 68 gallbladder cancers, 33 extrahepatic bile duct cancers, and 17 ampullary cancers. Survival was evaluated in 57 patients with gallbladder carcinomas, 27 with bile duct carcinomas, and 16 with ampullary carcinomas with and without somatic p16 alterations detected by two different methods., Results: p16 gene alterations including silent mutations were present in 61.8% gallbladder cancers, 54.5% bile duct cancers, and 70.6% ampullary cancers. p16 gene nonsilent mutations, p16 methylation, and loss of chromosome 9p21-22 that targets p14, p15, and p16 genes were present in 13 of 53 (24.5%), 8 of 54 (14.8%), and 32 of 44 (72.7%) gallbladder tumors; 5 of 25 (20.0%), 5 of 31 (16.1%), and 12 of 21 (57.1%) bile duct tumors; and 3 of 13 (23.1%), 6 of 15 (40.0%), and 8 of 16 (50.0%) ampullary tumors, respectively. The mean survival of patients with gallbladder cancers without p16 alterations was 21.5 +/- 14.8 months compared with 12.1 +/- 11.4 months for patients with p16 alterations (P = 0.02)., Conclusions: Alteration of p16 gene alone or in combination with alterations of other tumor suppressor genes on chromosome 9p is a prognostic indicator in gallbladder carcinoma, with more favorable survival rates associated with carcinomas lacking p16 gene alterations.

Objective: To study the relationship between obesity at different ages and the risk of endometrial cancer in urban Shanghai, China., Methods: In a population-based case-control study conducted in urban Shanghai, in-person interviews and anthropometric measurements were completed for 497 women at age 30 to 69 and an equal number of controls frequency-matched to cases on age distribution. All cases were newly diagnosed with endometrial cancer from January 1, 1997 to June 30, 2000. Unconditional logistic regression model was employed to estimate the adjusted odds ratios (ORs) and 95% confidence intervals (CIs) of the obesity at different ages., Results: After adjustment for some potential confounding variables, neither adolescent height nor weight was significantly related to endometrial cancer. Obesity in adulthood, except around 20 years old, was associated with elevated risks, with odds ratios for the highest versus lowest quartile of body mass index (BMI) being 1.5 (95% CI: 1.0 - 2.1), 1.7 (95% CI: 1.2 - 2.4), 1.9 (95% CI: 1.3 - 2.8) and 1.7 (95% CI: 1.0 - 2.7) at ages 30, 40, 50 and 60, respectively. Weight gain of more than 7.5 kg at different 10-year intervals in adulthood were associated with increased risk of endometrial cancer, whereas only weight gain more than 15% of initial weight from 40 to 50 years old significantly related to the risk. Only weight loss from ages 20 to 30 was inversely associated with endometrial cancer risk (OR = 0.4, 95% CI: 0.2 - 0.8). Current body weight, BMI and waist-to-hip ratio (WHR) were independent risk factors to endometrial cancer while standing height and sitting-to-standing height ratio were unrelated to the risk of endometrial cancer., Conclusion: Results indicated that adolescent obesity was unrelated to endometrial cancer. General obesity in adulthood, as well as body fat distribution, were associated with the risk of endometrial cancer independently. Weight changes before and after age 30 had different effects on the risk of endometrial cancer.

Although the majority of ecological and experimental studies have suggested a potential role of phytoestrogens in breast cancer prevention, findings from epidemiological studies have been inconsistent. Part of the inconsistencies may be attributable to the difficulty in measuring intake levels of phytoestrogens. Overnight urine samples from 250 incident breast cancer cases and their individually matched controls were analyzed for urinary excretion rates of isoflavonoids, mammalian lignans, and citrus flavonoids. The study subjects were a subset of the participants in the Shanghai Breast Cancer Study, a large population-based case-control study conducted in Shanghai from 1996-1998. To minimize potential influence of treatment on the exposure of interest, urine samples from breast cancer cases were collected before cancer therapy. Urinary excretion of total isoflavonoids and mammalian lignans was substantially lower in breast cancer cases than in controls. The median excretion rate of total isoflavonoids was 13.97 nmol/mg creatinine in cases and 23.09 in controls (P = 0.01), and the median excretion rate of total lignans was 1.77 in cases and 4.16 in controls (P < 0.01). The risk of breast cancer was reduced with increasing excretion of total isoflavonoids (P for trend, 0.04) and total lignans (P for trend, <0.01), with adjusted odds ratios of 0.62 (95% confidence interval, 0.39-0.99) and 0.40 (95% confidence interval, 0.24-0.64) observed for the highest versus the lowest tertile of total isoflavonoid and lignan excretion, respectively. The adjusted odds ratio was 0.28 (95% confidence interval, 0.15-0.50) for women who had a high excretion rate of both total lignans and isoflavonoids compared with those with a low excretion of both groups of phytoestrogens. No association was observed with citrus flavonoids. The results from this study suggest that high intake of certain phytoestrogens may reduce the risk of breast cancer.