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Microbial exoenzyme activity (EEA) and stoichiometry (EES) are of great significance to soil health through their influence on carbon (C), nitrogen (N), and phosphorus (P) cycling. However, when agricultural soil is contaminated by cadmium (Cd), the underlying mechanisms and effects on EEA and EES are still poorly understood. Here, we examine the effect of different remediation treatments (no amendment, 0.3% lime application, and 1.0% biochar application) on EEA and EES and the driving factors in a Cd-contaminated Brassica napus soil. The activities of a C-acquiring enzyme (β-1,4-glucosidase), N-acquiring enzymes (β-N-acetyl-glucosaminidase, leucine aminopeptidase, urease, and protease), and a P-acquiring enzyme (acid phosphatase), together with related environmental factors (soil pH and different Cd fractions), substrate factors (soil organic C, total N, and P content), and biotic factors (bacterial diversity and community composition) were analyzed. We found that lime and biochar amendments both significantly reduced EEA (normalized by the microbial biomass C), indicating lower microbial investment in exoenzyme production after remediation. Only lime amendment resulted in greater exoenzyme C:P and N:P ratios, and biochar application did not significantly affect EES. Among all the factors, the relative abundance of Acidobacteria and the bacterial Chao index, rather than available Cd content, accounted for the largest variations in soil EEA and EES, respectively. Additionally, the shoot Cd significantly decreased while the N and P content significantly increased after lime and biochar amendments. The higher shoot N content significantly associated with lower EEA and EES, suggesting that the rapeseed might modulate the microbial community and then the function based on nutrient status. Our results suggest that lime and biochar applications in mild Cd-contaminated soil tend to affect extracellular enzymes indirectly by mediating bacterial diversity, which may also be modulated by plant nutrient status. These results will provide useful information for Cd remediation and maintaining the sustainability of soil ecosystem services.

Peptide antigens have been widely used in the development of vaccines, especially for those against autoimmunity-inducing pathogens and cancers. However, peptide-based vaccines require adjuvant and/or a delivery system to stimulate desired immune responses. Here, we explored the potential of self-adjuvanting poly(hydrophobic amino acids) (pHAAs) to deliver peptide-based vaccine against Group A Streptococcus (GAS). We designed and synthesized self-assembled nanoparticles with a variety of conjugates bearing a peptide antigen (J8-PADRE) and polymerized hydrophobic amino acids to evaluate the effects of structural arrangement and pHAAs properties on a system's ability to induce humoral immune responses. Immunogenicity of the developed conjugates was also compared to commercially available human adjuvants. We found that a linear conjugate bearing J8-PADRE and 15 copies of leucine induced equally effective, or greater, immune responses than commercial adjuvants. Our fully defined, adjuvant-free, single molecule-based vaccine induced the production of antibodies capable of killing GAS bacteria.

Fallowing is an improvement process aimed at promoting the soil health and the sustainability of cultivated land. How it affects the soil health-related abiotic properties and microbial community composition under different levels of cadmium (Cd) contamination is not well known. This study involved applying consistent fallowing practices to paddy soils of low and high Cd content, in order to examine changes in the soil Cd, nutrient, and microbial community using a high-throughput sequencing method. Fallowing significantly decreased available Cd and phosphorus (P) content, but increased ammonium nitrogen (N) on lightly contaminated plots, whereas only P variables changed significantly for heavily contaminated plots. Furthermore, fallowing significantly decreased bacterial Shannon diversity on lightly contaminated plots and altered bacterial community composition on heavily contaminated plots, but it had no impact on archaeal or fungal communities, indicating that bacteria are more sensitive to fallowing than archaea and fungi. Specifically, fallowing significantly promoted some copiotrophic bacteria (Alphaproteobacteria and Betaproteobacteria) but suppressed some oligotrophic taxa (Chloroflexi phylum and OTU5837 belonging to the phylum Acidobacteria) on highly contaminated plots. Interestingly, the soil microbial community in the lightly contaminated plots was mainly affected by soil pH, C, and N properties, whereas on heavily contaminated plots, it was largely influenced by soil Cd and P variables. Overall, these findings showed that fallowing significantly improved soil N availability but decreased Cd availability in lightly contaminated conditions, while shifts in microbial community composition under heavily contaminated conditions may indirectly enhance soil nutrient availability and reduce available Cd. These findings highlight the significance of fallowing to promote the health and the sustainability of Cd-contaminated cultivated land.

Microplastic pollution is a major threat to the marine environment attracting attention from scientific and public communities. Although we have sufficient evidence that microplastic is ubiquitous in all ecosystems, the question of the harmfulness of microplastic exposure is still under debate. Filter feeders like bivalves are commonly exposed to microplastics in water and sediments and thus can serve as excellent biological indicators for microplastic pollution. A relatively rich toxicological literature has been focusing on microplastic effects on bivalves but we have yet to reach an agreement on the toxic effects and mechanisms of microplastics. Here, we conducted a meta-analysis and bibliometrics analysis of the microplastic studies in bivalves. The bibliometric analysis (used to evaluate the general research trends) showed that the investigation of microplastic distribution in the marine environment and the molecular mechanisms of microplastic toxicity are the two major hot spots of research. Based on analyses of ecologically and environmentally relevant microplastics concentrations, particle sizes and polymer types, we discuss the physiological effects of microplastics on bivalves, and the severity and direction of the effects at the cellular, tissue, organ and organismal levels. The meta-analysis results show that microplastics can induce time-dependent oxidative stress in bivalves. Generally, the activities of antioxidant enzymes, such as glutathione peroxidase (GPx), glutathione-S-transferase (GST) and superoxide dismutase (SOD) increased during short-term exposure but declined after long-term exposure to microplastics. Non-linear response of GPx, GST and SOD enzymes to MP exposure over time indicate that these enzymes are not good biomarkers of MPs effects in marine bivalves. The tissue glutathione levels and catalase (CAT activity) showed an increase during both short- and long term MP exposures and thus can be used as oxidative stress biomarkers of sublethal MPs effects in marine bivalves.

Peptide antigens have been widely used in the development of vaccines, especially for those against autoimmunity-inducing pathogens and cancers. However, peptide-based vaccines require adjuvant and/or a delivery system to stimulate desired immune responses. Here, we explored the potential of self-adjuvanting poly(hydrophobic amino acids) (pHAAs) to deliver peptide-based vaccine against Group A

5,10-Methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism is considered as a predisposition and promising genetic candidate to major depressive disorder (MDD), as it is associated with impaired one-carbon cycles, which may be involved in the pathogenesis of depression. Cortical thickness (CT) and subcortical structure volumes have been extensively studied in MDD and have been proposed as one of the phenotypes for MDD. We intend to discuss the association between CT, subcortical structure volume, and MTHFR C677T polymorphism in first-episode, treatment-naive patients with MDD. In this study, 127 adult patients with MDD and 101 age- and gender-matched healthy controls (HCs) were included. All subjects underwent T1-weighted MRI, MTHFR C677T genotyping, and FreeSurfer software-based morphological analysis. MDD patients have been detected to have significantly decreased volumes in the left nucleus accumbens (P < 0.001). The MTHFR 677 T allele carriers manifested with thinner CT in the left caudal anterior cingulate cortex (cACC, P = 0.009) compared with CC genotype. There were significant genotype-by-diagnosis interactions for the CT in the left cACC (P = 0.009), isthmus cingulate (P = 0.002), medial orbitofrontal lobe (P = 0.012), posterior cingulate (P = 0.030), and the right lateral orbitofrontal lobe (P = 0.012). We also found a trend in the interaction effect on the volume of the left putamen (P = 0.050). Our results revealed that MTHFR C677T polymorphism may be involved in the dysfunction of limbic–cortical–striatal–pallidal–thalamic (LCSPT) circuits mediating emotion processing, which may contribute to pathogenesis of MDD.

Since the beginning of the 21st century, the increasing production and application of nano-TiO

Plastic particles cause toxic effects on marine organisms but whether food particles can affect the toxic effects of plastic particles on filter feeding animals remains unknown. To evaluate the intake and physiological effects of different size particles and their exposure ways, the thick shell mussels Mytilus coruscus were exposed to polystyrene (PS) nanoplastics (NPs, 70 nm) and microplastics (MPs, 10 µm) respectively for two weeks by mixing NPs/MPs with microalgae or exposed to MNPs individually after feeding. Intake of particles and their physiological effects including energy budget, digestive enzymes and oxidative responses were assessed after exposure. Results indicated food presence mediate the effects while MPs decrease the energy budget and increase the catalase activity and malondialdehyde levels. Moreover, exposure way significantly affected energy budget and size of particle had a significant impact on enzyme activities. Our results showed MPs induce more significant effects than NPs on mussels, emphasized the importance of particle exposure way and suggested that mixture exposure with microalgae alleviate the influences on mussels caused by plastic particles alone. This study emphasized that we need to take the food particles into account for evaluating the toxic effects of plastic particles on filter feeding animals in the natural environment.

Titanium dioxide nanoparticles (nano-TiO

Climate change is projected to impact on biodiversity conservation and the effectiveness of the existing protected area network in biologically rich Yunnan Province of southwestern China. A statistically derived bioclimatic stratification is used to analyze projected bioclimatic conditions across Yunnan by the year 2050. The multi-model approach is based on an ensemble of CIMP5 Earth System Models, down-scaled to a set of 1 km(2) resolution climate projections (n = 63), covering four representative concentration pathways (RCP). Nine bioclimatic zones, composed of 33 strata, are currently found within Yunnan. By 2050, the mean elevation of these zones is projected to shift upwards by an average of 269 m, with large increases in area of the warmer zones, and decreases in the colder, higher elevation zones. Temperate and alpine areas of high biodiversity value are at risk. Displacement in the geographic distribution of bioclimatic conditions is likely to have substantial impact across all bioclimatic zones, vegetation types, and habitats currently found in Yunnan. On average, across all RCPs, 45% of the total combined area of the protected area network will shift to a completely different zone, with 83% shifting to a different strata. The great majority of protected area will experience substantially changed, spatially shifted, and novel bioclimatic conditions by 2050. The spatial displacement and upwards shifting of bioclimatic conditions indicates a prolonged period of significant ecological perturbation, which will have a major impact upon the conservation effectiveness of the established protected area network, and other conservation efforts across Yunnan. (C) 2015 Elsevier Ltd. All rights reserved.

Understanding the habitat use and spatial distribution of wildlife can help conservationists determine high-priority areas and enhance conservation efforts. We studied the wintering habitat use, preference, and utilization distribution of two crane species, that is, the black-necked crane (Grus nigricollis, Przevalski, 1876) and common crane (Grus grus, Linnaeus, 1758), in Huize National Natural Reserve, Yunnan–Guizhou Plateau, southwestern China. Line transects indicated that anthropogenic farmland habitat was highly utilized and was positively selected by both crane species (>90% of flocks observed for both species). Black-necked cranes preferred marshland in spring (February and March) but avoided grassland during the entire wintering period, whereas common cranes avoided both marshland and grassland throughout the entire period. The two cranes species had communal nightly roosting sites and separate daily foraging sites. Black-necked cranes were distributed within two km (1.89 ± 0.08 km) of the roosting site, covering an area of 283.84 ha, with the core distribution area encompassing less than 100 ha. In contrast, common cranes were distributed far from the roosting site (4.38 ± 0.11 km), covering an area of 558.73 ha, with the core distribution area encompassing 224.81 ha. Thus, interspecies competition may have influenced the habitat preference and spatial distribution divergence of these two phylogenetically related species. This study should help guide habitat management as well as functional zoning development and adjustment in the future. Based on our results, we recommend restoration of additional wetlands, retention of large areas of farmland, and protection of areas that cranes use most frequently.

In the greater Himalayan region, wetland ecosystems such as lakes, marshes, and peat lands play an important role in regulating the flow of major rivers. These ecosystems are often overlooked and not well represented on land-use planning and conservation maps. Wetland complexes are partly ephemeral and difficult to map accurately either with digital image processing or visual interpretation. This study developed a hybrid method of extracting spatial patterns of wetland areas which combines month-on-month multispectral classifications of Moderate Resolution Imaging Spectroradiometer data with a sample wetland extraction method based on knowledge of the spectral characteristics of satellite data and wetland ecological systems. The results were compared with the best available sources for lakes and wetlands on global and national scales. It was demonstrated that the method could extract wetlands automatically to a reasonable degree of accuracy and, therefore, reduce the need for extensive ground knowledge. The model was transferred by adjusting parameters through application of high-resolution satellite data (Landsat) in some sub-basin areas. These findings are cognizant with field interviews conducted by wetland experts. The hybrid method and high-altitude wetlands maps will provide decision makers with valuable information about wetland distribution and change in response to global warming and human activities.

Tibetan nomads in the Tibetan Autonomous Region of China have experienced profound transitions in recent decades with important implications for land use, livelihoods, and health development. The change from being traditional nomads to agropastoralists engaged in permanent agriculture, a sedentary village life (known as "sedentarization"), has been associated with a remarkable change in diet and lifestyle, decline in spatial mobility, increase in food production, and emerging infectious and noncommunicable diseases. The overarching response of the government has been to emphasize infrastructure and technological solutions. The local adaptation strategies of Tibetan nomads through maintaining balanced mobile herding, reindeer husbandry, as well as off-farm labor and trade could address both the cause of environmental degradation and improve the well-being of local people. Drawing on transdisciplinary, preliminary field work in Gangga Township of Dingri County in the foothills of Mt. Everest, we identify pertinent linkages between land use and health, and spatial and temporal mismatch of livelihoods and health care services, in the transition to sedentary village life. We suggest emerging imperatives in Ecohealth to help restore Tibetan livelihoods in transition to a sedentary lifestyle.