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A 120-day field experiment was conducted to investigate the responses of soil N2O emissions, plant biomass N content, and N cycling-related functional genes to yak (Bos grunniens) dung pat size, including full-size dung pat (FDP), 1/4FDP, 1/8FDP, and 1/16FDP (i.e., FDP split into four, eight, and sixteen equal-sized dung pat fragments) in an alpine steppe on the Qinghai-Tibetan Plateau. The yield-scaled and cumulative N2O emissions were lower in the 1/16FDP and 1/8FDP than in the FDP and 1/4FDP treatments. In addition, the 1/16FDP treatment had the smallest N2O emission factor (0.002%), possibly due to lower denitrification as shown by the lower nisS, nirK, and nosZ gene copy numbers in the first (day 30) and second (day 72) samplings, and increased aboveground plant N concentration and content, which was 23–32% and 21–36%, respectively, greater than in the other treatments. In conclusion, splitting the yak dung pat into 1/16 fragments would be an effective strategy for managing yak dung to reduce N2O emissions and improve aboveground plant biomass N content which enhances the sustainability of alpine steppe ecosystems on the Qinghai-Tibetan Plateau. The implication from this study is that long-term field experiments should be conducted to further investigate the potential antagonistic or synergistic effects of yak dung pat fragmentation combined with other amendments (e.g., nitrogen inhibitors, lime, or biochar) on reducing N2O emissions.

Examining transcriptomic and metabolic responses of earthworms to microplastic-contaminated soil is critical for understanding molecular-level toxicity of microplastics; yet very little research on this topic exists. We investigated influences of environmentally relevant concentrations (ERC) of polypropylene (PP) and polyethylene (PE) microplastic-contaminated soil on earthworms at the transcriptomic, metabolic, tissue and whole-body levels to study their molecular toxicity. The addition of PP and PE at ERC induced oxidative stress on earthworms, as indicated by the high enrichment of glutathione metabolism and increased glutamine at the transcriptomic and metabolic levels. Digestive and immune systems of earthworms were damaged according to the injuries of the intestinal epithelium, partial shedding of chloragogenous tissues and unclear structure of coelom tissues, which were confirmed by pathway analysis at the transcriptomic level. Significant enrichment of arachidonic acid and glycerolipid metabolisms indicated that PP and PE disturbed the lipid metabolism in earthworms. Significantly increased betaine and myo-inositol, and decreased 2-hexyl-5-ethyl-3-furansulfonate suggested that PP and PE caused differences in osmoregulation extent. In conclusion, most similar responses of earthworm might result from special size rather than type effects of PP and PE microplastics. Contamination of soils with microplastics even at ERC has health risks to earthworms; therefore, proper management of microplastics to reduce their input to the environment is key to reducing the health risks to soil fauna.

Details of the important experimental conditions of the synthesis of Cr doped TiO2 thin films by means of co-deposition by magnetron sputtering process are presented. Furthermore, a brief description of the structural, electrical and optical characterizations set-up is provided. These physical characterizations are based on X-ray diffraction, atomic force and scanning electronic microscopy, LBIC… techniques.

A new series of copper(II) complexes derived from (4,5-dimethyl-3-pyrazolyl) aldazine (DMPA), formulated as: (a) [LCuX2]·nEtOH; (b) [LCu(H2O)](ClO4)2; and (c) [LCuX]BF4·nH2O, where n = 1/2 or 1, X = Cl or Br and L = DMPA, have been synthesized. The formulations are based on elemental analyses and molar conductivity data. I.r., u.v.-vis., e.s.r. and magnetic data reveal that the complexes are trigonal bipyramidal, tetrahedral and stacked square-planar structures for (a), (b) and (c), respectively. The trigonal bipyramidal structure for class (a) compounds is confirmed using the atom superposition and electron delocalization-molecular orbital calculations, which agree with the experimental electronic spectral data. Variable temperature magnetic susceptibility data shows a ferromagnetic interaction within copper(II) complexes of class (c).

BALB/c mice inoculated nasally with Acanthamoeba culbertsoni, resulting in amebic encephalitis and death 3-7 days, were treated with rifampicin prophylactically (daily for 2 days with 75 and 100 mg/kg) and after infection (daily for 5 days with doses of 10-100 mg/kg). Prophylactic treatment resulted in full protection against infection, as assessed by absence of symptoms of central nervous system malfunction and negative brain culture 10 days after inoculation. Curative treatment was effective at the same doses; however, at doses of 10, 25, and 50 mg/kg, only two of six animals were free of symptoms and infection.