ArgR regulates motility and virulence through positive control of flagellar genes and inhibition of diguanylate cyclase expression in Aeromonas veronii.

Flagella are essential for biofilm formation, adhesion, virulence, and motility. In this study, the deletion of argR resulted in defects in flagellar synthesis and reduced motility, nevertheless, the underlying mechanism by which ArgR regulated bacterial motility remained unclear. ChIP-Seq and RNA-Seq analysis revealed that ArgR regulated the expression of flagellar genes, concluding two-component system flrBC and multitudinous flagellar structure genes.

Response of C:N:P stoichiometry to long-term drainage of peatlands: Evidence from plant, soil, and enzyme.

Drought induced by climate warming and human activities regulates carbon (C) cycling of peatlands by changing plant community composition and soil properties. Estimating the responses of peatlands C cycling to environmental changes requires further study of C: nitrogen (N): phosphorus (P) stoichiometric ratios of soil, plants, and enzyme activities. However, systematic studies on the stoichiometry of above-ground and below-ground ecosystems of peatlands post drainage remain scarce.

[Effects of Conservation Tillage on Herbicide Residues in Maize Field Soil].

It is well known that conservation tillage can improve soil quality, such as soil organic matters. However, limited information on the conservation tillage impacts on pesticides has been reported, which is important to food security. To explore the specific effects of conservation tillage on herbicide residues in soils, parallel soil samples from seven sites under traditional tillage and conservation tillage were collected, respectively, in Jilin Province, Northeast China.

Cobalt and nitrogen co-doped monolithic carbon foam for ultrafast degradation of emerging organic pollutants via peroxymonosulfate activation.

Cobalt-based catalysts are expected as one of the most promising peroxymonosulfate (PMS) activators for the removal of organic pollutants from industrial wastewater. However, the easy agglomeration, difficult separation, and secondary pollution of cobalt ions limit their practical application. In this study, a novel, highly efficient, reusable cobalt and nitrogen co-doped monolithic carbon foam (Co-N-CMF) was utilized to activate PMS for ultrafast pollutant degradation.

Does Shift in Vegetation Abundance After Nitrogen and Phosphorus Additions Play a Key Role in Regulating Fungal Community Structure in a Northern Peatland?

Soil fungal communities are key players in biogeochemical processes of peatlands, which are important carbon stocks globally. Although it has been elucidated that fungi are susceptible to environmental changes, little is known about the intricate and interactive effect of long-term nitrogen (N) and phosphorus (P) enrichment on fungal community structure in northern peatlands. In this study, we compared a short- (2 years) with a long-term (10 years) fertilization experiment in a peatland complex in northeastern China to assess how N and/or P additions influence fungal community structure.

The temporal distribution of platinum group elements (PGEs) in PM.

In this paper, Changji, Xinjiang, northwest China, was selected as the study area, and platinum group elements (PGEs) in PM were quantified by ICP-MS using microwave digestion. The results indicated that the average concentrations (and range) of Rh, Pd, and Pt in PM were 0.21 (n.

Effects of drainage on dissolved organic carbon (DOC) characteristics of surface water from a mountain peatland.

Dissolved organic carbon (DOC) plays an important role in regulating the carbon cycles in the peatland. In this study, we collected surface water once or twice a month from natural and drained areas of peatland in the Changbai Mountain, northeastern China, and determined the concentrations, spectral information, and composition of DOC, as well as the concentrations of other elements. The results showed that the concentrations of total N and NH in the drained area were significantly higher than those in the natural area in most cases, but concentrations of total dissolved Fe were significantly lower.

Induced defense and its cost in two bryophyte species.

Premise: Current knowledge about defense strategies in plants under herbivore pressure is predominantly based on vascular plants. Bryophytes are rarely consumed by herbivores since they have ample secondary metabolites. However, it is unknown whether bryophytes have induced defenses against herbivory and whether there is a trade-off between growth and defense in bryophytes.

Response of palladium in receiving water bodies to rainfall-runoff.

Palladium (Pd) is widely used in automotive catalytic converters to reduce toxic gas emissions. The input of Pd in the rainfall-runoff is an important contributing factor to the accumulation of Pd in receiving water bodies. In this study, the Meishe River in Haikou, Hainan Province, China, was used as the research area, and palladium (Pd) was selected as the target pollutant.

Shift in nitrogen transformation in peatland soil by nitrogen inputs.

Inputs of nitrogen (N) to peatlands in the form of fertilizers have rapidly increased due to the intensification of agricultural systems, impacting ecological processes, and the carbon storage function of peatland. However, detailed information on the impacts of long-term N inputs on the individual steps of N transformation processes in peatland soils still needs to be fully understood. We investigated N mineralization and nitrification rates as well as nitrite dependent anaerobic methane oxidation (n-damo), anaerobic ammonium oxidation (anammox), denitrification, and dissimilatory nitrate reduction to ammonium (DNRA) in a peatland affected by N inputs for >50 years, using isotope tracing technique and quantitative PCR.

Characteristics of polycyclic aromatic hydrocarbons (PAHs) in soil horizon from high-altitude mountains in Northeastern China.

Previous studies have reported that soils from high altitude mountains act as primary reservoirs of polycyclic aromatic hydrocarbons (PAHs). This study aims to investigate the spatial distribution and illuminate the behaviors of PAHs in soil profiles from Mt. Wangtiane in Northeastern China.

Mercury and arsenic in the surface peat soils of the Changbai Mountains, northeastern China: distribution, environmental controls, sources, and ecological risk assessment.

The potential toxic risk of mercury (Hg) and arsenic (As) in the soils of mining regions and other artificially disturbed lands receives considerable research attention. However, limited investigation has been conducted into the surface soils of natural globally distributed ecosystems, for example peatlands. In this study, we examine the distribution, controlling factors, sources, and potential ecological risks of Hg and As in 96 samples from 42 peatlands in the Changbai Mountains of northeastern China.

Degradation of polycyclic aromatic hydrocarbons (PAHs) during Sphagnum litters decay.

The dynamics of polycyclic aromatic hydrocarbon (PAH) degradation in Sphagnum litters and the decomposition of the litters were investigated. PAH concentration decreased to approximately half of the initial concentration as Sphagnum litters decayed. The initial PAH concentration was 489.

The impact of drying on structure of sedimentary organic matter in wetlands: Probing with native and amended polycyclic aromatic hydrocarbons.

Wetland sediments undergo dry-wet cycles that may change their structural properties and affect geochemical behavior of associated organic compounds. In this study, we examined the effect of drying on particle size distributions and the rapid (24h) sorption reactions of polycyclic aromatic hydrocarbons (PAHs) with salt marsh sediments in Nueces Delta, South Texas. Drying reduced the fraction of fine particles in organically richer sediments, indicating structural rearrangement of organic matter and mineral aggregates.

Assessment of polycyclic aromatic hydrocarbons in indoor dust from varying categories of rooms in Changchun city, northeast China.

Sixteen polycyclic aromatic hydrocarbons (PAHs) were isolated from indoor dust from various categories of rooms in Changchun city, northeast China, including dormitory, office, kitchen, and living rooms. PAH concentrations ranged from 33.9 to 196.

Concentrations and sources of polycyclic aromatic hydrocarbons in surface coastal sediments of the northern Gulf of Mexico.

Background: Coastal sediments in the northern Gulf of Mexico have a high potential of being contaminated by petroleum hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), due to extensive petroleum exploration and transportation activities. In this study we evaluated the spatial distribution and contamination sources of PAHs, as well as the bioavailable fraction in the bulk PAH pool, in surface marsh and shelf sediments (top 5 cm) of the northern Gulf of Mexico.

Results: PAH concentrations in this region ranged from 100 to 856 ng g-1, with the highest concentrations in Mississippi River mouth sediments followed by marsh sediments and then the lowest concentrations in shelf sediments.

Effects of crude oil exposure on bioaccumulation of polycyclic aromatic hydrocarbons and survival of adult and larval stages of gelatinous zooplankton.

Gelatinous zooplankton play an important role in marine food webs both as major consumers of metazooplankton and as prey of apex predators (e.g., tuna, sunfish, sea turtles).

Interactions between zooplankton and crude oil: toxic effects and bioaccumulation of polycyclic aromatic hydrocarbons.

We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1) the effects of crude oil (Louisiana light sweet oil) on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in mesozooplankton communities, (2) the lethal effects of dispersant (Corexit 9500A) and dispersant-treated oil on mesozooplankton, (3) the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4) the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L(-1) in 16 h.

[Simulation of multimedia fate of phenanthrene in the Yangtze estuary].

A Level III fugacity model is used to simulate the concentration distribution of phenanthrene in air, water, sediment and plants in the Yangtze estuary. Based on simulation results, transfer fluxes among-phase are calculated, and also, the key model parameters are determined by means of sensitivity analysis. The results indicated that the advection of air is the main source of phenanthrene in this area, while the main disappeared way from the study region is the advection of air and water.

Distribution of PAHs in tissues of wetland plants and the surrounding sediments in the Chongming wetland, Shanghai, China.

Polycyclic aromatic hydrocarbons (PAHs) concentrations were determined in sediments and three types of wetland plants collected from the intertidal flats in the Chongming wetland. The concentration of total PAHs in sediments ranged from 38.7 to 136.

[The follow-up study on P50 auditory sensory gating in naïve schizophrenia].

Objective: To understand the variations of sensory gating P50 in naïve schizophrenia during follow-up and the relations with positive and negative symptom scale (PANSS).

Methods: The data of auditory evoked potential P50 were recorded by USA Nicolet Brova instrument from 58 naïve schizophrenia patients (Sch) and 108 normal controls (NC) at baseline, Months 1, 2 and 3 after treatment. And a simultaneous assessment of PANSS was made.

Multiple 'hits' during postnatal and early adulthood periods disrupt the normal development of sensorimotor gating ability in rats.

In the present study, we evaluated a multiple-hit animal model of schizophrenia in an attempt to capture the complex interactions among various adverse developmental factors in schizophrenia. Sprague-Dawley rats were assigned to receive either repeated daily 3-h maternal separation for eight days (first 'hit') on postnatal days (PND) 3 to 10, and/or avoidance conditioning for six days (second 'hit') on PND 49-56, and/or repeated phencyclidine treatment (third 'hit', 3.0 mg/kg, sc) immediately after each daily avoidance conditioning.

Susceptibility of schizophrenia and affective disorder not associated with loci on chromosome 6q in Han Chinese population.

Background: Several linkage studies across multiple population groups provide convergent support for susceptibility loci for schizophrenia - and, more recently, for affective disorder - on chromosome 6q. We explore whether schizophrenia and affective disorder have common susceptibility gene on 6q in Han Chinese population.

Methods: In the present study, we genotyped 45 family trios from Han Chinese population with mixed family history of schizophrenia and affective disorder.

[Association between depression and G72 gene polymorphism].

Objective: To investigate the association between G72 gene polymorphisms and depression,and to probe the difference of G72 gene polymorphisms between depression with and without mixed family history.

Methods: The polymorphisms of G72 gene (rs947267 and rs2181953) were detected by PCR technique in 100 depressive patients without mixed family history, 50 depressive patients with mixed family history and 86 normal controls.

Results: (1) The frequencies of rs947267 genotypes and alleles in female depressive patients without mixed family history were significant different to the controls (P=0.