Purpose The coronavirus disease 2019 (COVID-19) outbreak impacts physical and mental health. The purpose of this study was to explore the association between the levels of social support and mental health among Chinese adolescents during the outbreak. Methods A total of 7,202 adolescents aged 14–18 years completed online survceys from March 8 to 15, 2020, in China. Researchers assessed the associations between depression symptoms (Patient Health Questionnaire-9), anxiety symptoms (Chinese version of the 7-item Generalized Anxiety Disorder scale), and social support (Social Support Rate Scale). Results COVID-19 exposure was associated with a higher prevalence of depression symptoms (odds ratio [OR] = 1.38, 95% confidence interval [CI]: 1.14–1.66) and anxiety symptoms (OR = 1.26, 95% CI: 1.04–1.52). Only 24.6% of adolescents reported high levels of social support. Most adolescents (70%) reported medium levels of support, and 5.4% reported low support. Low support was associated with higher prevalence of depression (OR = 4.24, 95% CI: 3.38–5.33) and anxiety symptoms (OR = 3.18, 95% CI: 2.54–3.98), while controlling for gender, grade, living situation, and COVID-19 exposure; similarly, medium support was associated with higher prevalence of depression (OR = 2.79, 95% CI: 2.48–3.15) and anxiety (OR = 2.19, 95% CI: 1.94–2.48) symptoms. Conclusions This study indicates there is a higher prevalence of mental health problems among adolescents with medium and low levels of social support in China during the outbreak of COVID-19.

The development of the gut is controlled and modulated by different interacting mechanisms, such as genetic endowment, intrinsic biological regulatory functions, environment influences and last but no least, the diet influence. In this work, we compared the fecal microbiota of breast-fed (BF), formula-fed (FF), and mixed-fed (MF) infants from Hebei Province, China. By using high-throughput 16S rDNA sequencing analyses, we found some differences in gut microbiota in the three groups. Firmicutes and Proteobacteria were the dominant bacteria at the phylum level in the three groups, where FF infants showed a significant depletion in Bacteroidetes (p < 0.001) and Actinobacteria (p < 0.05). Enterobacteriaceae was the dominant bacteria at the family level in the three groups, but FF infants showed higher Enterobacteriaceae enrichment than BF and MF infants (p < 0.05); the abundance of the Bifidobacteriaceae was only 8.16% in the feces of BF infants, but higher than in MF and FF infants (p < 0.05). The number of genera detected (abundance >0.01%) in BF, MF, and FF infants was only 15, 16, and 13, respectively. This study could provide more accurate and scientific data for the future study of infant intestinal flora.

We have developed a new method for the synthesis of CdTe and PbTe nanocrystals by using TeO2 with trioctylphosphine oxide as Te precursor. Using this method, uniform-sized CdTe nanocrystals are successfully synthesized without the use of any air-sensitive alkylphosphine. The monodispersity, size, and shape of as-synthesized CdTe nanocrystals are well-controlled using “green” chemicals at elevated temperatures; the photoluminescence emission of CdTe nanocrystals covers a wide range from 510 to 750 nm. Oleic acid has been chosen as the only ligand to achieve controllable synthesis of CdTe nanocrystals with not only different sizes covering from green to red emissions but also different crystal structures (wurtzite and zinc blende) and shapes (including spherical, tetrapod, dendrimer, and flower) by simply adjusting the injection and/or growth temperatures. PbTe nanocrystals with spherical and cubic shapes have also been synthesized successfully with this new tellurium precursor and they can easily self-assemble into two-dimensional ordered structures. Special attention has also been paid to the studies of the new molecular mechanisms involved in the formation of metal telluride nanocrystals.

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Rice can simultaneously absorb Fe 2+ via a strategy I-like system and Fe(III)-phytosiderophore via strategy II from soil. Still, it remains unclear which strategy and source of Fe dominate under distinct water conditions. An isotope signature combined with gene expression was employed to evaluate Fe uptake and transport in a soil−rice system under flooded and drained conditions. Rice of flooded treatment revealed a similar δ 56 Fe value to that of soils (Δ 56 Fe rice−soil = 0.05‰), while that of drained treatment was lighter than that of the soils (Δ 56 Fe rice−soil = −0.41‰). Calculations indicated that 70.4% of Fe in rice was from Fe plaque under flooded conditions, while Fe was predominantly from soil solution under drained conditions. Up-regulated expression of OsNAAT1, OsTOM2, and OsYSL15 was observed in the root of flooded treatment, while higher expression of OsIRT1 was observed in the drained treatment. These isotopic and genetic results suggested that the Fe(III)−DMA uptake from Fe plaque and Fe 2+ uptake from soil solution dominated under flooded and drained conditions, respectively.

A fermentative facultative anaerobe, strain HS01 isolated from subterranean sediment, was identified as Aeromonas hydrophila by 16S rRNA sequence analysis. The biotransformation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDD), and 1,1-dichloro-2,2-bis (4-chlorophenyl) ethane (DDE) by HS01 was investigated in the presence of goethite and anthraquinone-2,6-disulphonic disodium salt (AQDS). The results demonstrated that HS01 was capable of reducing DDTs, goethite and AQDS. And goethite can significantly enhance the reduction of DDT, DDD and DDE to some extent, while the addition of AQDS can further accelerate the reduction of Fe(III) and DDTs. The products of DDT transformation were identified as a large amount of dominant DDD, and small amounts of 1-chloro-2,2-bis-(p-chlorophenyl)ethane (DDMU), unsym-bis(p-chlorophenyl)-ethylene (DDNU), and 4,4'-dichlorobenzophenone (DBP). The results of cyclic voltammetry suggested that AQDS could increase the amounts of reactive biogenic Fe(II), resulting in the enhanced transformation of DDTs. This investigation gives some new insight in the fate of DDTs related to iron- and humic-reducing bacteria.

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