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Presence of cadmium in soil affects the growth status of plants; research on the underlying mechanism has focused on its lethal and sublethal consequences in plants, ignoring the impacts of soil organisms. Therefore, this study designed a microorganism – earthworm – plant ecosystem, investigated the influence of Cd (0, 0.3, 1.0, and 3.0 mg kg−1) on the growth of Arabidopsis thaliana in the presence of earthworms (Eisenia fetida), and revealed the mechanisms from the perspective of altered relationships among different soil organisms. In this study, there was no significant difference in the death rate of earthworms with low Cd addition concentration, but the microorganisms in earthworms and soil microorganisms changed, abundance of Actinomycetes in soil increased, while Planctomycetes decreased, Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microorganisms affect soil pH, which in turn affects soil physicochemical properties and the form of cadmium in soil. Compared with the control, soil pH significantly decreases under cadmium stress, Under 0.3 mg kg−1 treatment, soil total nitrogen, available phosphorus and total potassium are 181.11, 5.09, 51.90, and 7.55 mg kg−1, respectively, They were significantly higher than control group. Improved the growth environment of Arabidopsis thaliana and promoted the absorption of Cd in soil which affected the proportion of available Cd in the soil (when Cd was added at 1.0 mg kg−1, the proportion of available Cd in the soil decreased significantly from 95.05% to 49.40%). A. thaliana also absorbed more Cd, which increased Cd toxicity, and the reproductive growth of A. thaliana was enhanced, while vegetative growth was weakened.Compared with the control group (278.11 mg), the biomass of A. thaliana decreased significantly to 189.83 mg when Cd was supplemented at 0.3 mg kg−1. Therefore, the activities of and interactions among earthworms, plants, and microorganisms play important roles in reducing soil heavy metals and improving soil properties. HIGHLIGHTS: Under cadmium (Cd) stress, the relative abundance of Actinomycetes in soil increased, while Planctomycetes decreased. The relative abundance of Mycobacterium in the gut of Eisenia fetida decreased under Cd stress. Microbial changes and E. fetida activity changed soil physical and chemical properties and reduced the ratio of soil available Cd. Microorganisms and E. fetida enhanced the reproductive growth and weakened the vegetative growth of Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) treatment has always been challenging for elderly menopausal females. An animal model with a closer genetic association to human OP is essential for treatment research. Given its close genetic association to primates, the tree shrew is a suitable candidate for meeting the requirements for such an animal model. In the present study, a tree shrew OP model induced by ovariectomy (OVX), was established. Evaluation by multiple analysis methods, including blood biochemical indicators, uterus coefficients, micro-computed tomography analysis, histochemical analysis and scanning electron microscopic observation indicated that OVX was an appropriate method to establish the OP model in tree shrews. In addition, the biomolecular characteristics of OVX-induced osteoporosis were also assessed by transcriptome sequencing and bioinformatics analysis. The present study provides the methods used to confirm the successful establishment of the OP model in tree shrew, and suggests that the OP model is appropriate for human OP research. [ABSTRACT FROM AUTHOR]

Environmental pollutants can negatively affect grazer-induced defenses in phytoplankton species and lead to the disruption of phytoplankton-zooplankton relationships. However, it is still not known whether norfloxacin (NOR), a widely used antibiotic, has such effects on plankton systems when released into the environment. Here, we investigated the colony-forming ability of the green alga Scenedesmus quadricauda as well as the behavior (hopping frequency and duration of quiescence) and grazing rate of the cladoceran Daphnia magna , when exposed to different NOR concentrations (0, 50, 500, 5000 and 50,00 ug L −1 ), to determine the effects of NOR on the S. quadricauda - D. magna relationship. Colony size was generally unaffected by NOR but significantly increased when subjected to the stress of adding grazers; however, the combined effects of adding grazers and increasing NOR concentrations led to consistently decreased colony size compared to only adding grazers. The hopping frequency and the time spent on swimming of D. magna individuals decreased while their grazing rate increased with increasing NOR concentrations. Thus, NOR seemed to inhibit grazer-induced colony formation in S. quadricauda , resulting in more algal cells being consumed by grazers, despite inhibiting grazers’ feeding behavior. Considering that phytoplankton-zooplankton interaction plays an important role in determining ecological process of aquatic ecosystems, ecosystem function might be more affected by NOR contamination than previously recognized. [ABSTRACT FROM AUTHOR]

A modified Friedländer conversion of the cyclocondensation of aromatic o-aminonitriles with carbonyl compounds was discovered. Systematic studies reveal that both the new transformation and the classic Friedländer annulation in the presence of ZnCl2 constitute a pair of divergent reaction, and thecontrolled PDF transformation of this divergent reaction was achieved in the present of bases. [ABSTRACT FROM AUTHOR]

It has been reported that heavy metal contamination can affect litter decomposition and soil properties through its impact on microbial communities. However, it is still unclear whether the expected changes in earthworm activities in responses to heavy metal contamination could affect these properties. Therefore, we quantified earthworm (Eisenia fetida) responses in survival rate to lethal cadmium (Cd) concentrations (0, 50, 100, 150, 200, 250, and 300 mg L−1), and in burrowing ability, physiological characteristics, and feeding rate (on poplar leaf litter) to sub-lethal Cd concentrations (0, 15, 30, and 45 mg kg−1). Finally, sub-lethal influences of Cd on the decomposition rate of poplar leaf litter and on soil properties were investigated in the present of E. fetida. The 12-, 24-, 36-, and 48-h LC 50 of Cd for E. fetida were 276.0, 208.6, 192.6, 179.8 mg L−1, respectively. With increasing Cd concentration, malondialdehyde was stimulated, superoxide dismutase first increased and then decreased, while feeding rate, total borrowing length, and maximum burrowing depth consistently decreased. Consequently, leaf-litter decomposition rate and soil nutrient concentrations generally decreased with increasing Cd concentration. Our results indicate that, by affecting earthworm activities, Cd inhibited leaf-litter decomposition and led to the degradation of soil fertility. This study highlights the importance of earthworms in mediating soil functions under heavy metal stress. Image 1 • Earthworm activities, litter decomposition and soil properties to Cd were analyzed. • Cd caused physiological harm to earthworm cells. • Cd reduced feeding rate, biomass, burrowing ability of earthworms. • Cd reduced litter decomposition rate throughout affected earthworm activities. • Cd led to the degradation of soil fertility by retarding litter decomposition. [ABSTRACT FROM AUTHOR]

The 2008 world financial crisis had led many industrialised countries to endure a significant decline in their GDPs. Though the Chinese government arranged a 4 trillion RMB stimulus package coupled with 30 trillion RMB of new bank credits in 2008-2010 to mitigate the impact of the world financial crisis, the growth of China's international trade declined to a single-digit level after 10 years of rapid growth at more than 20% per annum since its WTO accession. The latest WTO Trade Policy Review for China is a timely piece of literature which provides excellent information on China's current economic situation, its trade and investment policies and government's priorities of policy support. In this article, we intend to reveal the latest development in the Chinese economy from the second half of 2011 and to predict what it may happen in the next a couple of years. China's determination to 'go global' has not faded and China can only become more open in the future. [ABSTRACT FROM AUTHOR]