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Electrochemical CO2 reduction (CO2R) in acidic media with Cu‐based catalysts tends to suffer from lowered selectivity towards multicarbon products. This could in principle be mitigated using tandem catalysis, whereby the *CO coverage on Cu is increased by introducing a CO generating catalyst (e.g. Ag) in close proximity. Although this has seen significant success in neutral/alkaline media, here we report that such a strategy becomes impeded in acidic electrolyte. This was investigated through the co‐reduction of 13CO2/12CO mixtures using a series of Cu and CuAg catalysts. These experiments provide strong evidence for the occurrence of tandem catalysis in neutral media and its curtailment under acidic conditions. Density functional theory simulations suggest that the presence of H3O+ weakens the *CO binding energy of Cu, preventing effective utilization of tandem‐supplied CO. Our findings also provide other unanticipated insights into the tandem catalysis reaction pathway and important design considerations for effective CO2R in acidic media. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction (CO2R) in acidic media with Cu‐based catalysts tends to suffer from lowered selectivity towards multicarbon products. This could in principle be mitigated using tandem catalysis, whereby the *CO coverage on Cu is increased by introducing a CO generating catalyst (e.g. Ag) in close proximity. Although this has seen significant success in neutral/alkaline media, here we report that such a strategy becomes impeded in acidic electrolyte. This was investigated through the co‐reduction of 13CO2/12CO mixtures using a series of Cu and CuAg catalysts. These experiments provide strong evidence for the occurrence of tandem catalysis in neutral media and its curtailment under acidic conditions. Density functional theory simulations suggest that the presence of H3O+ weakens the *CO binding energy of Cu, preventing effective utilization of tandem‐supplied CO. Our findings also provide other unanticipated insights into the tandem catalysis reaction pathway and important design considerations for effective CO2R in acidic media. [ABSTRACT FROM AUTHOR]

The defects, micropores, and microcracks on the plasma electrolytic oxidation (PEO) coating severely affect the long-term anti-corrosion feature. Inclusion of additives in the electrolyte is a feasible and effective strategy to attain the more intact PEO coating. The PEO coatings are fabricated on AZ31B Mg alloys in an silicon-based electrolyte with Na 3 VO 4 (OPEO), NaVO 3 (MPEO), and V 2 O 3 (VPEO), respectively, to explore the influence of additives on the corrosion resistance. MPEO sample has the smallest poriness and pore size unfolding the best anti-corrosion resistance, which is also consistent with the electrochemical analysis. Even after 336 h salt spray test, the MPEO coating exhibits the least corrosion. The excellent anti-corrosion performance of MPEO sample is the synergistic effect of inorganic salts and multiple metal oxides generated in the formation of PEO coating. Inclusion of inorganic salt with valence change metal is a feasible pathway to achieve the compact PEO coating since multiple metal oxides could be produced and deposited in the PEO coating during the fabrication. • Inorganic salt with valence change metal is taken as the additive. • PEO coating with NaVO 3 additive is not corroded after 14 days salt spray test. • Multiple species generated in the PEO process prompts the improved feature. [ABSTRACT FROM AUTHOR]

The phase engineering of transition metal dichalcogenides (TMDs) is considered a promising strategy for promoting efficient catalysis, such as the hydrogen evolution reaction (HER). While theoretical studies predict the presence of catalytically active atomic sites at heterophase boundaries in TMDs, conventional bulk HER measurements are not able to precisely explore these 1D heterophase regions for HER. Here, one reports on active HER occurring at heterophase boundaries between the semiconducting 2H and metallic 1T' phases in large‐scale MoTe2 grown via chemical vapor deposition. Microreactors are used to investigate the local HER at varying lengths of 1D heterophase boundaries, and the results are systematically compared with the HER performance at the pristine basal planes of MoTe2. Despite the small area ratio between the 1D heterophase boundary and the open region for local HER, a clear improvement in HER is observed with a turnover frequency of 317 s–1. The Kelvin probe force microscopy determines a surface potential difference of 50 mV across the heterophase boundary, which supports sharp band bending and local charge accumulation as the basis for the TMDs' efficient electrochemical catalysis. [ABSTRACT FROM AUTHOR]

Rare species are crucial components of the highly diverse soil microbial pool and over-proportionally contribute to the soil functions. However, much remains unknown about their assembling rules. The biogeographic patterns and species aggregations of the rare bacterial biosphere were assessed using 140 soil samples from a gradient of 2000 km across the main tea-producing areas in China. About 96% OTUs with ~40% sequences were classified as rare taxa. The rare bacterial communities were significantly affected by geographical regions and showed distance-decay effects, indicating that the rare bacteria are not cosmopolitan, they displayed a pattern of limited dispersal and were restricted to certain sites. Variation partitioning analysis (VPA) revealed that environmental variation and spatial factors explained 12.5% and 6.4%, respectively, of the variance in rare bacterial community. The Mantel and partial Mantel tests also showed that the environmental factors had stronger (~3 times) impacts than spatial factors. The null model showed that deterministic processes contributed more than stochastic processes in rare bacterial assembly (75% vs. 25%). There is likely an enrichment in ecological functions within the rare biosphere, considering this high contribution of deterministic processes in the assembly. In addition, the assembly of rare taxa was found to be mainly driven by soil pH. Overall, this study revealed that rare bacteria were not cosmopolitan, and their assembly was more driven by deterministic processes. These findings provided a new comprehensive understanding of rare bacterial biogeographic patterns and assembly rules. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ionic liquid is firstly utilized as the electrolyte additive for Mg-air battery. • Discharge potential and utilization efficiency are both boosted. • Working mechanism of [Ch][DHB] as electrolyte additive is clarified. • [Ch][DHB] is also suitable for other commercial Mg anodes, AM50, AZ31, and ZK61. A novel ionic liquid, choline 2,6-dihydroxytbenzoate ([Ch][DHB]), is firstly synthesized and utilized as the electrolyte additive for aqueous Mg-air cell based on the high purity Mg (Hp-Mg) with the aim to enhance the discharge performance. The half-cell discharge test, electrochemical measurement, and real-time hydrogen evolution are carried out to evaluate the influence of [Ch][DHB] and clarify the working mechanism. The [DHB]- anion could bind the Mg2+ ions to form the complex, which is beneficial to prompt the discharge of Mg matrix; while the [Ch]+ cation is effective to inhibit the self-corrosion of Mg anode. With the addition of 0.2 M [Ch][DHB] in the 3.5 wt% NaCl, both discharge potential and utilization efficiency are enhanced to −1.64 V SCE and 68.0 % under 5 mA cm−2. Based on the above Mg-air cell, 66 of LED bulbs (0.04 W/per bulb) would be maintained for 132 h with 0.2 M [Ch][DHB] in the electrolyte, while they are only kept for 65 h in the reference electrolyte. The 0.2 M [Ch][DHB] is also suitable electrolyte additives for Mg-air battery based on other commercial Mg anodes (AM50, AZ31, and ZK61). The specific energy of Mg-air batteries based on Hp-Mg, AM50, AZ31, and ZK61 in 0.2 M [Ch][DHB] electrolyte are 2093 Wh kg−1, 1788 Wh kg−1, 1896 Wh kg−1, and 713 Wh kg−1 at 5 mA cm−2, respectively. This work exhibits a promising pathway to enhance the discharge performance of Mg-air primary battery, including both discharge potential and utilization efficiency, with ionic liquids as electrolyte additives. [ABSTRACT FROM AUTHOR]

Sepsis is a potentially fatal condition caused by infection. It is frequently difficult to distinguish sepsis from systemic inflammatory response syndrome (SIRS), often resulting in poor prognoses and the misuse of antibiotics. Hence, highly sensitive and specific biomarkers are needed to differentiate sepsis from SIRS. Urine samples were collected and segregated by group (a sepsis group, a SIRS group, and a healthy control group). iTRAQ was used to identify the differentially expressed proteins among the three groups. The identified proteins were measured by ELISA in urine samples. Finally, all the acquired data were analyzed in SPSS. C-reactive protein, leucine-rich alpha glycoprotein-1 and serum amyloid A (SAA) protein were differentially expressed among the three groups. The adjusted median concentrations of urinary C-reactive protein were 1337.6, 358.7, and 2.4 in the sepsis, SIRS, and healthy control groups, respectively. The urinary leucine-rich alpha glycoprotein-1 levels in these three groups were 1614.4, 644.5, and 13.6, respectively, and the levels of SAA were 6.3, 2.9, and 0.07, respectively. For all three of these measures, the sepsis group had higher levels than the SIRS group (P < 0.001), and the SIRS group had higher levels than the healthy control group. When combined, the three biomarkers had a sensitivity of 0.906 and a specificity of 0.896 in distinguishing sepsis from SIRS. Urinary C-reactive protein, urinary leucine-rich alpha glycoprotein-1 and urinary SAA have diagnostic value in cases of sepsis. This initial study suggests the possibility of improved differential diagnosis between sepsis and systemic inflammatory response syndrome; additional confirmation is necessary to corroborate the findings. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis and Staphylococcus aureus are frequently co-isolated from biofilm-associated infections. A new study by Ch'ng et al. revealed that S. aureus -released heme feeds E. faecalis respiration, augmenting E. faecalis growth and overall biofilm biomass. Their finding further supports the theory that metabolite cross-feeding is a critical aspect shaping polymicrobial biofilm interactions. [ABSTRACT FROM AUTHOR]

Background and aims: Root-associated fungi link resource fluxes between the soil and roots, thus influencing plant growth and ecosystem function. However, at present, the impact of global warming on these fungi and their plant host specialization, especially in ecosystems on the Qinghai-Tibetan Plateau is obscure. Methods: Here, pot experiments were conducted to examine the root-associated fungal community structure of 14 host plant species undergoing two years of experimental warming on the Qinghai-Tibetan Plateau. Infrared heaters were used to raise the soil temperature to 2.0 ℃ higher than the relative ambient temperature. Subsequently, the endophytic and rhizoplane fungal communities were explored by sequencing the fungal internal transcribed spacer (ITS) region. Results: A total of 1564 OTUs were identified, which were dominated by ascomycetes (82.71%). Similar root-associated fungal diversity and community composition were identified under ambient and warming environments. The root-associated fungal community composition significantly varied among different host plant species, and this dissimilarity was enhanced under experimental warming. Root N concentration was essential in shaping the structure of the root-associated fungal community. Conclusions: Although the root-associated fungal community was resilient to short-term warming, our study highlights that climate warming can induce higher host specificity of root-associated fungal communities in the alpine meadow ecosystem. [ABSTRACT FROM AUTHOR]

Summary: A host‐plant and its associated microbiota depend on one another. However, the assembly process and the functioning of host‐associated microbiota are poorly understood.Herein, rice was used as model plant to investigate the assemblage of bacterial microbiota, including those in the seed, root endosphere and rhizosphere. We also assessed the degree to which endosphere and rhizosphere communities were influenced by vertical transmission through seed and identified the core microbes that potentially associated with plant phenotypic properties.Plant microhabitat, rather than subspecies type, was the major driver shaping plant‐associated bacterial microbiota. Deterministic processes were primarily responsible for community assembly in all microhabitats. The influence of vertical transmission from seed to root‐associated bacterial communities appeared to be quite weak (endosphere) or even absent (rhizosphere). A core microbial community composed of 15 generalist species persisted across different microhabitats and represented key connectors in networks. Host‐plant functional traits were linked to the relative abundance of these generalist core microbes and could be predicted from them using machine learning algorithms.Overall, bacterial microbiota is assembled by host‐plant interactions in a deterministic‐based manner. This study enhances our understanding of the driving mechanisms and associations of microbiota in various plant microhabitats and provides new perspectives to improve plant performance. [ABSTRACT FROM AUTHOR]

This study focused on the legacy effects of 8-year application of N (in gradient of 0, 140, 280, 470, and 660 kg N ha−1 year−1) on the bacterial community diversity, interactions, and assembly processes in the wheat rhizosphere. The rhizosphere bacterial α-diversity increased with the rate of historical N input, while it did not change at N addition rates of over 280 kg N ha−1 year−1. Historical N input clearly shifted the rhizosphere bacterial community composition, and soils with more N input were more dissimilar to those without N input. The net relatedness index (NRI) and nearest taxon index (NTI) analysis revealed that the rhizosphere bacterial communities in most samples were phylogenetically clustered, and the treatments with high N (> 470 kg N ha−1 year−1) showed higher levels of clustering than those with low N (< 140 kg N ha−1 year−1), indicating more environmental selection stress in soil with higher historical N input. Increased co-occurrence network size and connectivity were accompanied by increased aboveground biomass of wheat. Overall, with the increase in historical N input, the resulting legacy effects forced the bacterial community in the rhizosphere to undergo higher environmental selection pressure, and indirectly affected the complexity of wheat rhizosphere assemblages during subsequent crop growth. [ABSTRACT FROM AUTHOR]

Summary: In the processes controlling ecosystem fertility, fungi are increasingly acknowledged as key drivers. However, our understanding of the rules behind fungal community assembly regarding the effect of soil fertility level remains limited.Using soil samples from typical tea plantations spanning c. 2167 km north‐east to south‐west across China, we investigated the assemblage complexity and assembly processes of 140 fungal communities along a soil fertility gradient.The community dissimilarities of total fungi and fungal functional guilds increased with increasing soil fertility index dissimilarity. The symbiotrophs were more sensitive to variations in soil fertility compared with pathotrophs and saprotrophs. Fungal networks were larger and showed higher connectivity as well as greater potential for inter‐module connection in more fertile soils. Environmental factors had a slightly greater influence on fungal community composition than spatial factors. Species abundance fitted the Zipf–Mandelbrot distribution (niche‐based mechanisms), which provided evidence for deterministic‐based processes.Overall, the soil fungal communities in tea plantations responded in a deterministic manner to soil fertility, with high fertility correlated with complex fungal community assemblages. This study provides new insights that might contribute to predictions of fungal community complexity. [ABSTRACT FROM AUTHOR]

Two Cu(II) metal complexes, {[Cu(bmem)(CH 3 OH)(CH 3 O)](ClO 4)} n (1) and {[Cu(bmem)(CH 3 O)(SCN)](CH 3 OH) 0.75 } n (2) based on 1-(benzotriazole-1-methyl) -1-(2-ethylimidazole) (bmem) were synthesized. The X-ray single crystal diffraction analysis reveals that complexes 1 and 2 both display 1D chain structure containing binuclear copper units. Then the ligand and complexes 1 and 2 were examined for hypoglycemic activity against α-amylase and antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and found that two Cu(II) complexes showed more activity than the ligand bmem. Both complexes 1 and 2 have strong inhibitory effects on α-amylase, and the IC 50 values of complexes 1 (1.97 mg/mL) and 2 (1.83 mg/mL) are lower than that of acarbose (2.3 mg/mL) and ligand (10.89 mg/mL). The scavenging rates on DPPH radical of complexes 1 (80.46%, 150 μg/mL) and 2 (63.08%, 150 μg/mL) are significantly higher than that of ligand (6.92%, 150 μg/mL). In addition, the fluorescence properties and thermal stability of metal complexes were determined. Image 1 • Two new benzotriazole-based Cu(II) complexes 1 and 2 were synthesized. • Complexes 1 and 2 display 1D chain structure containing binuclear copper units. • The hypoglycemic activities against α-amylase of complexes 1 and 2 were investigated in vitro. • The antioxidant activities of complexes 1 and 2 were evaluated by the DPPH free radical scavenging assay. [ABSTRACT FROM AUTHOR]

Background and aims: The increasing input of anthropogenically-derived nitrogen (N) to ecosystems raises a crucial question: how do N inputs modify the soil microbial stability, and thus affect crop productivity? Methods: Soils from an 8-year rice-wheat rotation experiment with increasing N-input rates were subjected to drying–rewetting (DW) cycles for investigating the resistance and resilience of soil functions, in terms of abundances of genes (potential functions) and activities of enzymes (quantifiable functions), to this stress, and particularly the contribution of resistance and resilience on crop production was evaluated. Results: Although the DW cycles had a stronger effect compared to N fertilization level, the N input was also important in explaining the variation in the resistance and resilience of functional genes and the activities of enzymes involved in C, N and P cycling. Crop yields benefited from both of high resistance and high resilience of soil microbial functions, though the resistance and resilience of soil enzyme activities exhibited a stronger contribution to crop yields compared to the functional genes and the overall contribution strength was conditioned by N input levels. Conclusions: In addition to the well-known direct contribution of N fertilization on crop yields, N input plays an indirect role on crop production via conditioning the resistance and resilience of soil functions in response to repeated DW cycles. [ABSTRACT FROM AUTHOR]

Three new complexes formulated as [Cu(mbmb) 2 Cl 2 ] (1), [Cu(mbmb) 2 (NO 3) 2 ] (2), and [Zn(mbmb) 2 Cl 2 ] (3) (mbmb = 1-[(2-methyl-1H-benzoimidazol-1-yl)methyl]-1H-benzotriazole) have been synthesized and characterized. Complexes 1 – 3 showed mononuclear structures and the central metal ions of complexes 1 – 3 exhibited a four-coordinated environment. We evaluated the antioxidant activity against DPPH and antidiabetic activity against α-amylase of complexes 1 – 3 and ligand (mbmb) in vitro. The results of DPPH free radical scavenging assay showed that complexes 1 and 2 exhibited higher antioxidant activity among the synthesized compounds and their IC 50 values were 43.72 μg/mL and 43.76 μg/mL, respectively. The IC 50 values in vitro antidiabetic studies of complex 1 (0.74 mg/mL) and complex 2 (1.00 mg/mL) were much smaller than those of standard acarbose (2.34 mg/mL) and the ligand mbmb (39.87 mg/mL), which showed effective inhibition on α-amylase. Additionally, the solid-state fluorescent properties of these three complexes and ligand mbmb were investigated at room temperature. Unlabelled Image • Three new benzimidazole-based Cu(II)/Zn(II) complexes 1 – 3 were synthesized. • The structure of complexes 1 – 3 was characterized adequately by X-ray study. • The antioxidant activities of complexes 1 – 3 were evaluated by the DPPH free radical scavenging assay. • The antidiabetic activities against α-amylase of complexes 1 – 3 were investigated in vitro. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, namely poly[[hexathiocyanatotetrakis{μ3‐2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene}tricadmium(II)] 3.5‐hydrate], {[Cd3(SCN)6(C18H21N9)4]·3.5H2O}n (1), and poly[[hexathiocyanatotetrakis{μ3‐2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene}trizinc(II)] 3.5‐hydrate], {[Zn3(SCN)6(C18H21N9)4]·3.5H2O}n (2), have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction analysis. From the X‐ray analysis, it is noteworthy that polymers 1 and 2 are isostructural, with their three‐dimensional structures composed of three kinds of four‐connection metal ions and two kinds of three‐connection 2,4,6‐trimethyl‐1,3,5‐tris[(triazol‐1‐yl)methyl]benzene (TTTMB) ligand nodes. Each metal ion is six‐coordinated in a slightly distorted octahedral geometry. The antioxidant activity against DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) and the antidiabetic activity against α‐amylase of the synthesized compounds were evaluated in vitro. The results of the DPPH free‐radical scavenging assay showed that polymers 1 and 2 exhibited strong antioxidant effects, with IC50 values of 3.81 and 2.56 mg ml−1, respectively. The IC50 value in the antidiabetic studies of polymer 1 was 3.94 mg ml−1, while polymer 2 exhibited no antidiabetic activity. Polymers 1 and 2 revealed different inhibitory activities on DPPH and α‐amylase, which indicated that the metal ions play important roles in the biological activity of coordination polymers. In addition, the solid‐state photoluminescence properties and thermal stability of 1 and 2 have been investigated. [ABSTRACT FROM AUTHOR]

Plasma electrolytic oxidation (PEO) coating has been widely applied for the magnesium alloys to resist the corrosion. However, the defaults on the PEO surface greatly weaken its long-term anti-corrosion performance. To fill the micropores is an efficient and feasible strategy to refine the compactness and anti-corrosion of PEO coating and achieve the additional function. Although various sealing pathways are reported in past decades, the leakage of filler and long-term anti-corrosion performance are still the perplexing issues. The corrosion inhibitor 1-methyl-3-(carboxyundecyl)imidazolium bis(trifluoromethylsulfonyl)imide ([MCIM][NTf 2 ], MN), is grafted on the clinochrysotile-like magnesium silicate nanotubes (MSNTs) by the post-synthesis method, then, the MSNTs@MN is filled into the micropores on the PEO surface by the post-sealing process to form PEO/MSNTs@MN. According to the electrochemical results in 3.5 wt% NaCl solution, the log |Z| 0.01Hz is increased by 1.26 times after the sealing. After immersion in 3.5 wt% NaCl solution for 120 h, the log |Z| 0.01Hz of PEO/MSNTs@MN is still the 1.56 times larger than that of PEO. The PEO coating filled by the MSNTs@MN offers the consistently superior corrosion resistance up to 336 h of salt spray tests with 5.0 wt% NaCl solution. The superior anti-corrosion performance of PEO/MSNTs@MN is associated with the cooperation of physical barrier of PEO coating and protection from MSNTs@MN. The grafted corrosion inhibitor would not leak easily, which is favorable to achieve the long-term anti-corrosion performance. The immobilized MN provides the active anti-corrosion in the initial corrosion stage achieving the self-healing function. Moreover, the release of corrosion inhibitor, MN, does not rely on the smart trigger, which broadens the scope of immobilized materials. This work introduces a facile and one-step strategy to seal the pores on the PEO surface with the self-healing function and improved anti-corrosion capability. [Display omitted] • Novel hybrid coating PEO/MSNTs@MN with self-healing and long-term anti-corrosion • A simple one-step strategy is introduced to seal the pores on the PEO surface. • The immobilized MSNTs@MN provides the active anti-corrosion functionalization. • Anti-corrosion feature is kept after 336 h salt spray tests in 5 wt% NaCl. [ABSTRACT FROM AUTHOR]

• Fertilization regimes affected straw-C incorporation into amino sugars. • Higher 13C-fungal residues accumulated in NPK plus manure supplied soil. • Higher straw-13C transformed into bacterial C in NPK-treated soil. • NPKM soil sustained greater recovery of 13C in total amino sugars by the end. • Straw-13C amino sugars contributed differentially to 13C-SOC in different soils. Emerging evidences have emphasized the primacy of microorganisms as executor in soil organic C (SOC) formation. Yet, whether and how microbial transformation of crop residue-derived C into necromass is affected by fertilization regimes remains poorly understood. To address this, soils subjected to 3-year applications of chemical fertilizer (NPK) vs manure plus chemical fertilizer (NPKM) were incubated with or without addition of 13C-labelled rice straw for 60 days. The 13C incorporation into amino sugars (microbial necromass biomarker) was identified by using an amino sugar-based stable isotope probing approach. The straw-C were transformed more rapidly into total amino sugars (13C-AS s) in NPK-treated soil, while more pronounced 13C-AS s accumulation occurred in NPKM soil at later stage, indicating temporal microbial C uptake to generate necromass varied depending on fertilization regimes. Moreover, straw-derived fungal C was significantly higher in NPKM over NPK while bacterial counterpart reversed during the incubation. Our results reinforced changes in microbial communities and their C utilization capacities for efficient residue production in different fertilized soils. Additionally, NPKM-treated soil sustained a prolonged but likely more efficient utilization of straw-C with increasing time as evidenced by significantly higher percentage of straw-dervied C enrichment in 13C amino sugar pools by the end of incubation. These findings reveal that fertilization regimes can alter response strategies of microbial transformation of plant C into microbial-derived C. Together with differential contributions of these newly-formed microbial C to SOC pool, our work highlights the key role of microbial anabolisms in building up SOC following crop residue return to soils under different fertilization regimes. [ABSTRACT FROM AUTHOR]

Biodiversity can effectively actuate ecosystem multifunctionality, and the relationships primarily depend on the circumstances. However, the relative functional importance of particular components in complex biocoenosis, such as abundant and rare taxa, influencing soil multifunctionality changes across environmental gradients and remains limited understanding. Here, 152 independent soil samples from aridity (from 0.47 to 0.97) and elevation (from 142 to 2766 m a.s.l.) gradients across steppes of northern China were collected and analyzed to obtain information of soil bacterial community and soil functional properties, which were further utilized to evaluate how the relationships between the diversities of abundant and rare species and soil multifunctionality respond to changes in aridity and elevation. At aridity and elevation levels of ~0.85 and ~1100 m a.s.l., respectively, abrupt variations of the connections between soil multifunctionality and diversities of abundant or rare taxa occurred. Moreover, the results revealed a significantly positive effect of richness of abundant taxa on soil multifunctionality in the less arid and higher elevation areas, whereas a strongly positive relationship was exhibited between diversity of rare species and soil multifunctionality in the more arid and higher elevation regions. Specially, regardless of higher or lower aridity levels, both contributions of abundant and rare taxa to soil multifunctionality were extremely weak in the lower elevation regions. Our study highlights the importance of aridity and elevation impacting the contributions of abundant and rare taxa in regard to soil multifunctionality, which can positively provide some theoretical bases for promoting ecosystem sustainability and productivity under global climate change. • Abrupt shifts occurred at aridity and elevation levels of about 0.85 and 1100 m a.s.l., respectively. • Abundant taxa showed a positive effect in the less arid and higher elevation areas. • Rare taxa exhibited a positive effect in the more arid and higher elevation areas. • Both abundant and rare taxa showed weak effects in the lower elevation regions. [ABSTRACT FROM AUTHOR]

Summary: Chemoautotrophic ammonia‐oxidizers and nitrite‐oxidizers are responsible for a significant amount of soil nitrate production. The identity and composition of these active nitrifiers in soils under different long‐term fertilization regimes remain largely under‐investigated. Based on that soil nitrification potential significantly decreased in soils with chemical fertilization (CF) and increased in soils with organic fertilization (OF), a microcosm experiment with DNA stable isotope probing was further conducted to clarify the active nitrifiers. Both ammonia‐oxidizing archaea (AOA) and bacteria (AOB) were found to actively respond to urea addition in soils with OF and no fertilizer (CK), whereas only AOB were detected in soils with CF. Around 98% of active AOB were Nitrosospira cluster 3a.1 in all tested soils, and more than 90% of active AOA were Nitrososphaera subcluster 1.1 in unfertilized and organically fertilized soils. Nitrite oxidation was performed only by Nitrospira‐like bacteria in all soils. The relative abundances of Nitrospira lineage I and VI were 32% and 61%, respectively, in unfertilized soils, and that of Nitrospira lineage II was 97% in fertilized soils, indicating long‐term fertilization shifted the composition of active Nitrospira‐like bacteria in response to urea. This finding indicates that different fertilizer regimes impact the composition of active nitrifiers, thus, impacting soil nitrification potential. [ABSTRACT FROM AUTHOR]

Highlights • Richness and phylogenetic diversity indexes were similar in the different treatments and soil type. • Bacterial abundance and phylogenetic diversity decreased significantly following N enrichment. • N fertilization and soil type individually or jointly mediated the bacterial community structure. • Soil microbial parameters coupled with abiotic factors contributed directly and indirectly to maize yields. Abstract Although the effects of nitrogen (N) fertilization on soil microflora have been well studied, the effects should be verified across soil types and N-added levels. To understand the impacts of N fertilization on shifts in soil biological traits and bacterial communities and to further explore the coupling mediation of these parameters with respect to crop yields, we sampled soils from three experimental sites (each site received three levels of N fertilization (0, 168 and 312 kg N ha−1)) that share the same climatic conditions but have different soil types (clay, alluvial and sandy soils). In clay and sandy soils, total microbial biomass with N fertilization treatments was lower than that with no treatment, and the N and carbon (C) contents of microbial biomass with N fertilization treatments were higher than those without treatment. In alluvial soils, these properties were higher with N fertilization treatment than with no treatment. Together with N addition, bacterial abundance and phylogenetic diversity significantly decreased in alluvial and sandy soils. Soil type had a higher (38.82%, p < 0.001) individual impact on bacterial community structure than did N fertilization (18.92%, p < 0.001). Interactions between soil type and N fertilization also notably explained 11.08% of the altered community structure. Overall, N fertilization significantly affected soil physicochemical (such as pH, organic C and NO 3 --N) and biological properties (microbial biomass C and N), which can affect maize yield directly and indirectly by further mediating soil bacterial abundance, diversity and community structure, with consequences for crop production. Bacterial community structure (path coefficient = 0.64) had the most positive and direct impact on maize yield, followed by organic C (0.37) and available N (0.33). Altogether, these findings suggest that N fertilization affects soil biological traits and bacterial communities across different soil types. Further understanding these soil microbial parameters can contribute to crop yield and may provide deeper insight into predicting the coupling of soil functionality and crop productivity. [ABSTRACT FROM AUTHOR]

Ammonia oxidation, the primary and rate-limiting step of nitrification, is mediated by both ammonia-oxidizing archaea (AOA) and bacteria (AOB). However, the dominant environmental driver of the activity, abundance, diversity and composition of ammonia-oxidizers has not been well understood enough, and the relative contribution of AOA and AOB to nitrification is still under debate. Soils treated with different fertilization regimes in an over 35-year field experiment were collected to explore the variation in function and structure of ammonia-oxidizer communities and corresponding driver. The highest nitrification activity (44.49 mg N kg −1 soil d −1 ) was found in only organic fertilizer (O) treated soil, whereas the lowest activity (2.81 mg N kg −1 soil d −1 ) was observed in only mineral fertilizer (NPK) treated soil. Moreover, as 1-octyne was employed to discriminate AOA- and AOB-supported nitrification, AOA dominated (93.53%) the nitrification in the Control soil, while AOB contributed dominantly (84.73–89.10%) in all of the organic amended soils, and NPK-treated soil showed an almost equal contribution to AOA (45.79%) and AOB (54.21%). Compared with the Control soil, AOA abundance increased in soils with organic and low chemical fertilizer but decreased in only chemically treated soil, whereas the AOB abundance in all fertilized soils was greatly enhanced. The AOA activity was linearly dependent on AOA abundance, whereas the AOB activity was exponentially correlated with AOB abundance. The sequences of AOA and AOB in the Control soil were mostly affiliated with group I.1b thaumarchaeota and genus Nitrosospira clusters 3a.1. Soil treated with NPK increased the abundance of AOA that belonged to group I.1a-associated lineage, whereas more abundant AOB was related to Nitrosospira clusters 3a.2 and 8b. In contrast, the O-treated soil showed more abundant AOB that belonged to Nitrosospira clusters 3b and 8b. As revealed by aggregated boosted tree analysis, the soil ammonium (NH 4 + ) content was identified as the dominant driver of activity and diversity of AOA, and soil pH was considered to be the major influencing factor in abundance and composition of AOA; the AOB composition was mainly affected by soil NH 4 + content, the relative activity and diversity by soil pH, and the relative abundance by soil electrical conductivity (EC). Collectively, different fertilization regimes will result in variations in activity, abundance, diversity and composition of ammonia-oxidizers with distinct drivers. Our research could be helpful to identify better strategies for the mitigation of nitrate production in agricultural soils. [ABSTRACT FROM AUTHOR]

We introduce a facile and robust strategy for bonding a poly(methylmethacrylate) (PMMA) thermoplastic microdevice via ethanol treatment followed by thermal bonding at relatively low temperature and low pressure. Organic solvents can speed up bonding without sacrificing the optical properties of the PMMA substrate, but microchannels are often clogged by the solvent during the bonding process. To prevent channel clogging while achieving robust sealing, a microchannel was selectively treated hydrophobically, and then the entire surface of the PMMA was treated with ethanol at 80 °C for 30 min. Two pieces of PMMA were thermally pressed together at 60 °C for 20 min to obtain a permanent seal. Tensile strength measurement, high-throughput leakage test, and burst test were performed. The highest bonding strength was approximately 12.4 MPa, and the bonding was robust enough to endure intense liquid flow that was almost 450 times higher than the total internal volume of the microchannel. [ABSTRACT FROM AUTHOR]

Anti-corrosion inorganic-organic hybrid coating with the self-healing feature is still scare for the Mg alloys. The adhesion between various compositions is one troublesome problem. On the other hand, the incorporation of corrosion inhibitor would destroy the feature of organic film leading to the inferior anti-corrosion performance. The hybrid coating, PEO/IN/QSE, with the self-healing feature is firstly fabricated on Mg alloys, in which the corrosion inhibitor of imidazolium-based ionic liquid (IN) is embedded in the plasma electrolytic oxidation (PEO) pores and the superhydrophobic film (QSE) is covered on the top. The IN embedded in the pores of PEO layer does not destroy the feature of QSE film and improve the anti-corrosion performance of PEO layer. And it affords the self-healing function, which is determined by the anti-corrosion test with the scratched samples. More important, it strengthens the adhesion between QSE and PEO coating as a bridge. This work provides a feasible strategy to prepare the inorganic-organic composite film with the promising applications for the anti-corrosion of the Mg alloys. [Display omitted] • Composite coating PEO/IN/QSE with self-healing and superhydrophobic feature • Adhesion between PEO and QSE layer is strengthened by IN. • The pores of PEO are taken as the container for IN corrosion inhibitor. [ABSTRACT FROM AUTHOR]

Alkaline phosphomonoesterase (ALP) mainly originates from soil microbial secretion and plays a crucial role in the turnover of soil phosphorus (P). To examine the response of ALP-encoding microbial communities (analysed for the biomarker of the ALP gene, phoD) of soils and derivative soil fractions to different fertilisation regimes, soil samples were collected from a long-term experimental field (over 35 years). The different organic P (Po) pools of soil fractions and the ALP activity of soil were also determined. Compared with chemical-only fertilised soils, the ALP activity was 232-815% higher in organic-amended soils, and the highest enzyme activity was observed in the organic-only fertilised treatment. The abundance of the phoD gene harbouring in soil fractions, determined by quantitative PCR (qPCR), was affected by different fertilisations. The highest abundance of the phoD gene was generally detected in the 2-63-μm-sized fraction (silt), but most phoD-encoding microbial species were associated to the 0.1-2-μm-sized fraction (clay) in the chemical-only fertilised soil. The contents of labile Po (LPo), moderately labile Po (MLPo) and fulvic acid-associated Po (FAPo) were significantly correlated with the phoD gene abundance, whereas only LPo content was significantly correlated with the ALP activity. The dominant phoD-encoding phylas were Actinobacteria and Proteobacteria, according to a high-throughput sequencing. Bradyrhizobium, a N-fixer identified as a phoD-encoding genus, showed the highest abundance in fertilised soils. The abundance of Bradyrhizobium, Streptomyces, Modestobacter, Lysobacter, Frankia and Burkholderia increased with the organic-only amendment and was significantly correlated with the ALP activity. According to structure equation models (SEM), pH and LPo content significantly and directly affected the ALP activity; the soil organic C (C) content was related to composition and abundances of phoD-harbouring microbial communities; since both microbial properties were correlated to the ALP activity, the C content was indirectly related to the ALP activity. In conclusion, soil management practices can be used to optimise the contents of soil available P and the organic P with regulation of soil ALP activity and the community composition of corresponding microbes. [ABSTRACT FROM AUTHOR]

Both nitrogen (N) and phosphorus (P) may limit plant production in steppes and affect plant community structure. However, few studies have explored in detail the differences and similarities in the responses of belowground microbial communities to long-term N and P inputs. Using a high-throughput Illumina Miseq sequencing platform, we characterized the bacterial communities in a semi-arid steppe subjected to long-term N or P additions. Our results showed that both the Chao richness and Shannon's diversity were negatively correlated to N input rate, while only Chao richness was significantly and negatively correlated to P input rate. Also, both N and P additions altered the bacterial community structure. The bacterial community between plots of the same N or P input rate was much more dissimilar with the higher input level, indicating more severe niche differentiation in pots with higher N or P input. N Inputs significantly increased the relative abundance of the predicted copiotrophic groups ( Proteobacteria and Firmicutes ) but reduced the predicted oligotrophic groups ( Acidobacteria , Nitrospirae , Chloroflexi ), with the order Rhizobiales being most affected. P additions significantly affected only two phyla (Armatimonadetes and Chlorobi ), which were positively correlated with P source. Results from the structural equation modelling (SEM) showed that N additions affected the bacterial community primarily by changing the pH, while P additions did so mainly by improving P availability. Our results suggest that the below-ground bacterial communities are more sensitive to N inputs, but P inputs can also play an important role in bacterial niche differentiation. These findings improve our understanding of bacterial responses to N and P inputs, and their impacts on bacterial-mediated processes, especially in the context of increasing anthropogenic nutrient inputs. [ABSTRACT FROM AUTHOR]

TheFusariumwilt caused byFusarium oxysporumstrains is the most devastating disease of cucumber, banana, and tomato. The biological control of this disease has become an attractive alternative to the chemical fungicides and other conventional control methods. In this review, the research trends and biological control efficiencies (BCE) of different microbial strains since 2000 are reviewed in detail, considering types of microbial genera, inoculum application methods, plant growth medium and conditions, inoculum application with amendments, and co-inoculation of different microbial strains and how those affect the BCE ofFusariumwilt. The data evaluation showed that the BCE of biocontrol agents was higher against theFusariumwilt of cucumber compared to theFusariumwilts of banana and tomato. Several biocontrol agents mainlyBacillus, Trichoderma, Pseudomonas, nonpathogenicFusarium, andPenicilliumstrains were evaluated to controlFusariumwilt, but still this lethal disease could not be controlled completely. We have discussed different reasons of inconsistent results and recommendations for the betterment of BCE in the future. This review provides knowledge of the biotechnology of biological control ofFusariumwilt of cucumber, banana, and tomato in a nut shell that will provide researchers a beginning line to start and to organize and plan research for the future studies. [ABSTRACT FROM PUBLISHER]

The volatile organic compounds (VOCs) produced by soil microbes have a significant role in the control of plant diseases and plant growth promotion. In this study, we examined the effect of VOCs produced by Pseudomonas fluorescens strain WR-1 on the growth and virulence traits of tomato wilt pathogen Ralstonia solanacearum . The VOCs produced by P. fluorescens WR-1 exhibited concentration dependent bacteriostatic effect on the growth of R. solanacearum on agar medium and in infested soil. The VOCs of P. fluorescens WR-1 also significantly inhibited the virulence traits of R. solanacearum . The proteomics analysis showed that the VOCs of P. fluorescens WR-1 downregulated cellular proteins of R. solanacearum related to the antioxidant activity, virulence, inclusion body proteins, carbohydrate and amino acid synthesis and metabolism, protein folding and translation, methylation and energy transfer, while the proteins involved in the ABC transporter system, detoxification of aldehydes and ketones, protein folding and translation were upregulated. This study revealed the significance of VOCs of P. fluorescens WR-1 to control the tomato wilt pathogen R. solanacearum . Investigation of the modes of action of biocontrol agents is important to better comprehend the interactions mediated by VOCs in nature to design better control strategies for plant pathogens. [ABSTRACT FROM AUTHOR]

Significant differences in the microbial biomass and diversity in soil have been observed following long-term fertilization, but little research has explored the co-occurrence patterns among microbial taxa or functions. Soil samples from four long-term experiments in China were collected, and an Illumina amplicon sequencing of 16S rDNA amplicon was performed to decipher the differences in interactions and network organization arising from fertilization with organic amendment (OA) or chemical fertilizer (CF) across the sampling sites. We thus aimed to extend the analysis beyond the basic inventory descriptions of the composition and diversity of the microbiome and toward an assessment of relationships and effects. Nonmetric multidimensional scaling analysis revealed a clear difference between the soil microbiomes associated with the OA and CF treatments. Fertilization can interact with the soil chemical properties and sampling site, thereby significantly impacting the associated soil microbiome. Distinct network structures indicated that the OA network was characterized by more functionally interrelated operational taxonomic units (OTUs) than the CF network. The topological roles of individual OTUs and key microbial populations were distinctly different, although the generalists mainly belonging to Actinobacteria and Proteobacteria were observed in both networks. The different fertilization treatments had distinct effects on the soil pH, which represented a key variable to impact the associated microbial community modularity. Most functional groups involving carbon-, nitrogen- and phosphorus-related metabolism and recycling and antibiotic biosynthesis were present at significantly high abundance in the organic-amended soils. All of the functions with statistical significance could be traced to corresponding responsible major modules in the CF network, but it was not the case in OA soil. These results suggested that the soil functions were decentralized and assigned to small groups in OA soil. Overall, we demonstrated that long-term organic amendment supports stronger functional potentials and more interactions within soil community relative to long-term chemical-only fertilization, which may be related to OA benefits to soil stability and buffering capacity. These results explore the correlations, inter-taxa and between major groups and functional traits, to gain a more integrated understanding of microbiome and ecological rules guiding soil community fostered by fertilization regimes. [ABSTRACT FROM AUTHOR]

[Cd(C12H13N5)2Cl2], monoclinic, Cc (no. 9), a = 9.3081(2) Å, b = 11.7526(3) Å, c = 24.9876(6) Å, β = 94.184(2)°, Z = 4, V = 2726.23(11) Å3, Rgt(F) = 0.0412, wRref(F2) = 0.0581, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis is often coisolated with Pseudomonas aeruginosa in polymicrobial biofilm-associated infections of wounds and the urinary tract. As a defense strategy, the host innately restricts iron availability at infection sites. Despite their coprevalence, the polymicrobial interactions of these two species in biofilms and under iron-restricted conditions remain unexplored. Here, we show that E. faecalis inhibits P. aeruginosa growth within biofilms when iron is restricted. E. faecalis lactate dehydrogenase (ldh1) gives rise to l-lactate production during fermentative growth. We find that an E. faecalis ldh1 mutant fails to inhibit P. aeruginosa growth. Additionally, we demonstrate that ldh1 expression is induced under iron-restricted conditions, resulting in increased lactic acid exported and, consequently, a reduction in local environmental pH. Together, our results suggest that E. faecalis synergistically inhibits P. aeruginosa growth by decreasing environmental pH and l-lactate-mediated iron chelation. Overall, this study emphasizes the importance of the microenvironment in polymicrobial interactions and how manipulating the microenvironment can impact the growth trajectory of bacterial communities. [ABSTRACT FROM AUTHOR]

Background and aims: Grafting is commonly used to overcome soil-borne disease but how it affects the root-associated microbiome of concerned crops and the linkage between the microbiome and the resistance of soil-borne disease remain unknown. This study addressed the variation in the microbial activity and bacterial community in the rhizosphere of own-root bottle gourd (rootstock), own-root watermelon, and grafted-root watermelon under field conditions and tried to clarify how bacterial communities in the rhizosphere responded to grafting of watermelon. Methods: Seven types of soil enzyme activities were tested by microplate fluorometric assay, and the root-associated bacterial community was compared using 454 pyrosequencing. Results: Clear distinctions in microbial activity and taxonomic levels between the different treatments were obtained. Compared with grafted-root watermelon, ungrafted watermelon recruited significantly higher beneficial bacterial genera, such as Bacillus spp. and Paenibacillus spp., suggesting the grafted watermelon root could not have the ability to harbor highly beneficial bacteria to exert soil-borne disease resistance. However, a significantly higher Shannon-Wiener index at any reads level was found in the rhizosphere of grafted watermelon compared with ungrafted watermelon. Conclusions: Root-associated bacteria of grafted watermelon possess a broader niche overlap which would provide the potential to exclude the pathogen challenge. We proposed that the grafted watermelon might exert soil-borne disease resistance by maximizing the niche occupancy of rhizosphere rather than by recruiting more beneficial bacteria. [ABSTRACT FROM AUTHOR]

Background and aims: Paenibacillus spp. are widely considered to impact the fertility and health of soil. The aim of this study was to evaluate how different fertilization regimes affect the population size and community structure of Paenibacillus spp. over a long period of time in red soil. Methods: Soil samples were collected from a long-term experiment and were then analyzed using real-time PCR and PCR-DGGE. The correlation analysis, PCA and RDA were used to explore the relationships among Paenibacillus spp. population, community structure and soil properties in different treatments. Results: The pH was seriously decreased only by the application of chemical fertilizer. The largest population of Paenibacillus spp. was found in the soil treated with organic fertilizer application, while the richest diversity was observed in the soil treated only with the chemical fertilizer. The Paenibacillus spp., Paenibacillus alkaliterrae, Paenibacillus campinasensis, and Paenibacillus xylanilyticus were found in all treatments. Paenibacillus castaneae was found in the soil treated with NPK, and Paenibacillus pabuli was specifically observed in the lime-amended treatment. Paenibacillus taichungensis and Paenibacillus prosopidis were detected in the soil treated with only chemical fertilizer. Except for the ammonium and pH, all the tested soil fertility parameters (total C, total N, nitrate, available K and available P) could significantly affect both the Paenibacillus spp. population number and diversity. The soil pH was significantly correlated with Paenibacillus spp. diversity only. Conclusions: Our results indicate that the different long-term fertilization regimes have varied impact on both the Paenibacillus spp. population size and the diversity of the community associated with the soil properties tested. These results can help to enrich the information on the response of beneficial soil microbes to different long-term fertilization regimes. [ABSTRACT FROM AUTHOR]

Particle-size soils were fractionated for evaluating changes in the composition of bacterial community and enzyme activity in response to 13 years of fertilization. This study focused on Mollisol and its particle-size fractions of 200-2,000 μm (coarse sand sized), 63 to 200 μm (fine sand sized), 2 to 63 μm (silt sized), and 0.1 to 2 to μm (clay-sized). Long-term chemical fertilization lowered the pH of all particle fractions, whereas organic fertilizer application mitigated soil acidification. Nutrient concentrations depended on both fertilizer treatment and particle fractions and enzymes were unevenly active throughout the soil. Generally, the highest enzyme activities were observed in the silt and clay fractions of control soil and the soil treated with chemical fertilizer (N, P, and K (NPK)) and in the sand-sized fraction of soil treated with manure and chemical fertilizer (MNPK). Except for acid phosphomonoesterase, the other tested enzyme activities in coarse-sized fractions of MNPK soil were significantly higher than those of the control and NPK soils. Fertilization and soil fraction interactively ( p < 0.05) affected the enzyme activity. Denaturing gradient gel electrophoresis analysis showed that the bacterial community structure significantly differed in different particle sizes with a higher bacterial diversity in small-sized than in coarse-sized fractions. Dominant bands were excised and sequenced. We have found the following bacterial groups: Actinobacteria, γ-proteobacteria, and Acidobacteria. In addition, enrichment of organic matter in coarser fractions was related to greater bacterial diversity than any other treatment. Principal component analysis showed a smaller variability among fractions of the organic amended treatment. Redundancy analysis showed that the tested properties significantly affected the composition of bacterial community with the exception of C/N and available P. No significant correlation between enzyme activity and bacterial community composition was detected, whereas positive correlations between other soil properties and enzyme activities were observed to various extents. Probably, enzyme activities might be affected by specific functional bacterial communities rather than by the overall bacterial community. We concluded that the long-term application of organic manures contributed to the increase of soil organic matter content of particles higher than 200 mm, with higher bacterial diversity and increases in most of the enzyme activities. [ABSTRACT FROM AUTHOR]

Aims and background: Soil fertility quality index is a useful indicator that helps to improve sustainable land use management and achieve economical yield in agriculture production. The objectives of this study were to evaluate the changes of soil fertility quality between the 1980s and 2000s in different cropping systems and its significance to crop productivity and sustainability. Methods: We collected all published data on crop yields and soil parameters from 58 long-term experiments in three typical double-cropping systems in China, including maize-wheat (M-W), rice-rice (R-R) and rice-wheat (R-W) cropping systems, and selected seven fertilizer treatments in each experiment, including inorganic fertilizer [nitrogen and phosphorus fertilizer (NP), nitrogen and potassium fertilizer (NK), phosphorus and potassium fertilizer (PK) and balanced mineral fertilizer (NPK)], combined NPK with farmyard manure (NPKM) or crop straw (NPKS), and no fertilizer application (served as control). For comparison, an integrated fertility quality index (IFQI) was used to estimate the variations in soil fertility in different cropping systems. Moreover, the mean production variability index (PVI, %) in each cropping system was calculated to evaluate the stability of crop production. Results: Over cropping systems, the averaged relative yields of PK, NK and NP ranged from 38.0 to 97.4 %, while the mean yields can be increased by 2.4-5.1 % in NPKM, compared to NPK. The mean yields were similar between NPK and NPKS for maize and wheat crops, but the yield was increased by 4.3-10.0 % in NPKS. Among the different treatments, the highest variability of cereal productivity was obtained in NK, PK or Control, while the lowest value was mostly recorded in NPKM or NPKS in these three cropping systems. Relative to the control, the IFQIs in fertilization treatments were increased by 9.4-150.0 %, 6.2-41.5 % and 1.3-17.5 % in M-W, R-W and R-R systems, respectively (except for PK treatment in R-R system). However, changes of IFQI in topsoil differed among fertilizer treatments, and greater increases existed in the treatments receiving organic residues (NPKM and NPKS). Conclusions: The increase in crop yield is exponentially correlated with the increased IFQI over treatments in three cropping systems. Over the treatments and systems, production variability among years is shown to be negatively, linearly related to IFQI ( P < 0.001). Therefore, the high grain yield and low production variability can be simultaneously achieved by increasing soil fertility in all three cropping systems. [ABSTRACT FROM AUTHOR]

Abstract: The application method for a novel bioorganic fertilizer (BIO) was developed to improve its biocontrol efficacy of Fusarium wilt (Ling et al. 2010). However, its efficacy on controlling Fusarium wilt and the variations of microbial community after long-term application for watermelon production had not been elucidated. To clarify, a 4-years pot experiment of mono-cropping watermelon was conducted. The results revealed that though the disease incidences were increased in all treatments with the increase of continuous cropping years, the treatment of BIO application both in nursery and pot soil always maintained the lowest disease incidence. The real-time PCR results showed that the population of Paenibacillus polymyxa was decreased with continuous cropping years, but in all seasons, the treatment with BIO application both in nursery and pot soil had a highest population of P. polymyxa than the other treatments. On the other hand, the abundance of the pathogen FON was increased with the increase of continuous cropping years and the lowest rate of increase was found by BIO application in both nursery and pot soil. DGGE patterns showed that the bacterial diversity was weakened after mono-cropping of watermelon for 4 years, but the consecutive applications of BIO at nursery and transplanting stage resulted in the minimal change of bacterial diversity. More detailed differences on bacterial diversity between control and double application of BIO treatment after 4-years monoculture were analyzed by 454 pyrosequencing, which showed the dominant phyla found in both samples were Firmicutes, Proteobacteria and Actinobacteria, and the consecutive applications of BIO recruited more beneficial bacteria than control, such as Bacillus, Paenibacillus, Haliangium, Streptomyces. Overall, these results, to a certain extent, approved that the consecutive applications of BIO at nursery and transplanting stage could effectively suppress watermelon Fusarium wilt by regulating the rhizosphere bacterial diversity. These results could give some clues that how to regulate the soil microbial community to an appropriate level which can keep the plant healthy and thus control the soil-borne diseases. [Copyright &y& Elsevier]

Background: Overexpression of microRNA-182 (miR-182) is found in various human cancers, including non-small cell lung cancer (NSCLC). Our aim is to investigate the association of miR-182 expression with the sensitivity of NSCLC to cisplatin. Methods: TaqMan RT-PCR or Western blot assay was performed to detect the expression of mature miR-182 and programmed cell death 4 (PDCD4) protein. miR-182 and (or) PDCD4 depleted cell lines were generated using miR-182 inhibitor and (or) siRNA. The viabilities of treated cells were analyzed using MTT assay. Results: The expression level of miR-182 in A549 cell line was significantly higher than that in NHBE cell line (p < 0.01). Transfection of miR-182 inhibitor induced sensitivity of A549 cells to cisplatin. A549 cells transfected with PDCD4 siRNA became more resistant to cisplatin therapy. We found an increase PDCD4 protein level following the transfection of miR-182 inhibitor using Western blot analysis. In addition, the enhanced growth-inhibitory effect by miR-182 inhibitor was weakened after the addition of PDCD4 siRNA. Conclusions: The results of the present study demonstrated that overexpression of miR-182 may involve in chemoresistance of NSCLC cells to cisplatin by down-regulating PDCD4. [ABSTRACT FROM AUTHOR]

A new water-soluble polysaccharide (longan polysaccharide 1 (LP1)) was extracted and successfully purified from Dimocarpus longan pulp via diethylaminoethyl (DEAE)-cellulose anion-exchange and Sephacryl S-300 HR gel chromatography. The chemical structure was determined using Infrared (IR), gas chromatography (GC) and nuclear magnetic resonance (NMR) analysis. The results indicated that the molecular weight of the sample was 1.1 × 105 Da. Monosaccharide composition analysis revealed that LP1 was composed of Glc, GalA, Ara and Gal in a molar ratio of 5.39:1.04:0.74:0.21. Structural analysis indicated that LP1 consisted of a backbone of →4)-a-D-Glcp-(1→4)-a-D-GalpA- (1→4)-a-D-Glcp-(1→4)-ß-D-Glcp-(1→ units with poly saccharide side chains composed of →2)-ß-D-Fruf-(1→2)-L-sorbose-(1→ attached to the O-6 position of the a-D-Glcp residues. In vitro experiments indicated that LP1 had significantly high antitumor activity against SKOV3 and HO8910 tumor cells, with inhibition percentages of 40% and 50%, respectively. In addition, LP1 significantly stimulated the production of the cytokine interferon-γ (IFN-γ), increased the activity of murine macrophages and enhanced B- and T-lymphocyte proliferation. The results of this study demonstrate that LP1 has potential applications as a natural antitumor agent with immunomodulatory activity. [ABSTRACT FROM AUTHOR]

Highly expressible bacteriorhodopsin (HEBR) is a light-triggered protein (optogenetic protein) that has seven transmembrane regions with retinal bound as their chromophore to sense light. HEBR has controllable photochemical properties and regulates activity on proton pumping. In this study, we generated HEBR protein and incubated with lung cancer cell lines (A549 and H1299) to evaluate if there was a growth-inhibitory effect with or without light illumination. The data revealed that the HEBR protein suppressed cell proliferation and induced the G0/G1 cell cycle arrest without light illumination. Moreover, the migration abilities of A549 and H1299 cells were reduced by ~17% and ~31% after incubation with HEBR (40 μg/mL) for 4 h. The Snail-1 gene expression level of the A549 cells was significantly downregulated by ~50% after the treatment of HEBR. In addition, HEBR significantly inhibited the gene expression of Sox-2 and Oct-4 in H1299 cells. These results suggested that the HEBR protein may inhibit cell proliferation and cell cycle progression of lung cancer cells, reduce their migration activity, and suppress some stemness-related genes. These findings also suggested the potential of HEBR protein to regulate the growth and migration of tumor cells, which may offer the possibility for an anticancer drug. [ABSTRACT FROM AUTHOR]

Grafting watermelon onto bottle gourd rootstock is commonly used method to generate resistance to Fusarium oxysporum f. sp. niveum (FON), but knowledge of the effect of the root exudates of grafted watermelon on this soil-borne pathogen in rhizosphere remains limited. To investigate the root exudate profiles of the own-root bottle gourd, grafted-root watermelon and own-root watermelon, recirculating hydroponic culture system was developed to continuously trap these root exudates. Both conidial germination and growth of FON were significantly decreased in the presence of root exudates from the grafted-root watermelon compared with the own-root watermelon. HPLC analysis revealed that the composition of the root exudates released by the grafted-root watermelon differed not only from the own-root watermelon but also from the bottle gourd rootstock plants. We identified salicylic acid in all 3 root exudates, chlorogenic acid and caffeic acid in root exudates from own-root bottle gourd and grafted-root watermelon but not own-root watermelon, and abundant cinnamic acid only in own-root watermelon root exudates. The chlorogenic and caffeic acid were candidates for potentiating the enhanced resistance of the grafted watermelon to FON, therefore we tested the effects of the two compounds on the conidial germination and growth of FON. Both phenolic acids inhibited FON conidial germination and growth in a dose-dependent manner, and FON was much more susceptible to chlorogenic acid than to caffeic acid. In conclusion, the key factor in attaining the resistance to Fusarium wilt is grafting on the non-host root stock, however, the root exudates profile also showed some contribution in inhibiting FON. These results will help to better clarify the disease resistance mechanisms of grafted-root watermelon based on plant-microbe communication and will guide the improvement of strategies against Fusarium-mediated wilt of watermelon plants. [ABSTRACT FROM AUTHOR]

Abstract: Infection with the soil-borne pathogen Fusarium oxysporum f. sp. cucumerinum (FOC), which causes Fusarium wilt of cucumber plants, might result in changes in plant transpiration and water status within leaves. To monitor leaf response in cucumber infected with FOC, digital infrared thermography (DIT) was employed to detect changes in leaf temperature. During the early stages of FOC infection, stomata closure was induced by ABA in leaves, resulting in a decreased transpiration rate and increased leaf temperature. Subsequently, cell death occurred, accompanied by water loss, resulting in a little decrease in leaf temperature. A negative correlation between transpiration rate and leaf temperature was existed. But leaf temperature exhibited a special pattern with different disease severity on light–dark cycle. Lightly wilted leaves had a higher temperature in light and a lower temperature in dark than did in healthy leaves. We identified that the water loss from wilted leaves was regulated not by stomata but rather by cells damage caused by pathogen infection. Finally, water balance in infected plants became disordered and dead tissue was dehydrated, so leaf temperature increased again. These data suggest that membrane injury caused by FOC infection induces uncontrolled water loss from damaged cells and an imbalance in leaf water status, and ultimately accelerate plant wilting. Combining detection of the temperature response of leaves to light–dark conditions, DIT not only permits noninvasive detection and indirect visualization of the development of the soil-borne disease Fusarium wilt, but also demonstrates certain internal metabolic processes correlative with water status. [Copyright &y& Elsevier]

Abstract: Fusarium wilt of banana is caused by Fusarium oxysporum f. sp. cubense infection. The initial chlorosis symptoms occur progressively from lower to upper leaves, with wilt symptoms subsequently occurring in the whole plant. To determine the effect of the pathogen infection on the gas exchange characteristics and water content in banana leaves, hydroponic experiments with pathogen inoculation were conducted in a greenhouse. Compared with control plants, infected banana seedlings showed a higher leaf temperature as determined by thermal imaging. Reduced stomatal conductance (gs) and transpiration rate (E) in infected plants resulted in lower levels of water loss than in control plants. Water potential in heavily diseased plants (II) was significantly reduced and the E/gs ratio was higher than in noninfected plants, indicating the occurrence of uncontrolled water loss not regulated by stomata in diseased plants. As no pathogen colonies were detected from the infected plant leaves, the crude toxin was extracted from the pathogen culture and evaluated about the effect on banana plant to further investigate the probable reason of these physiological changes in Fusarium-infected banana leaf. The phytotoxin fusaric acid (FA) was found in the crude toxin, and both crude toxin and pure FA had similar effects as the pathogen infection on the physiological changes in banana leaf. Additionally, FA was present at all positions in diseased plants and its concentration was positively correlated with the incidence of disease symptoms. Taken together, these observations indicated that FA secreted by the pathogen is an important factor involved in the disturbance of leaf temperature, resulting in uncontrolled leaf water loss and electrolyte leakage due to damaging the cell membrane. In conclusion, FA plays a critical role in accelerating the development of Fusarium wilt in banana plants by acting as a phytotoxin. [Copyright &y& Elsevier]

Abstract: We previously developed a method for the application of bioorganic fertilizer to improve the biocontrol efficacy of Fusarium wilt (). However, the detailed behavior of Fusarium oxysporum f. sp. niveum (FON) and its antagonistic bacterium, Paenibacillus polymyxa SQR-21 (SQR-21), in the rhizosphere of watermelon after application of the bioorganic fertilizer had not been elucidated. A rhizobox experiment was carried out to investigate the distribution of FON and its antagonistic bacterium, SQR-21, in the soil at different distances from the watermelon rhizoplane by real-time PCR. The results confirmed that the bioorganic fertilizer (BIO) significantly suppressed Fusarium wilt and promoted the growth of the watermelon plants. Furthermore, we found that the application of BIO significantly enhanced the abundance of SQR-21 and reduced the population of FON in the soil near the rhizoplane as compared to the control. A maximal quantity (7.14log10copies/g soil) of P. polymyxa SQR-21 was obtained in the rhizosphere under the BIO treatment, and this number was decreased with increasing distance from the rhizoplane. The population of FON in the rhizosphere of the control was 2 orders of magnitude higher than under the BIO treatment, and with increasing distance from the rhizoplane, the FON abundance increased in the SQR-21 inoculated treatments and decreased in the treatments without SQR-21. In the soil far from the rhizoplane (bulk soil), both FON and SQR-21 reached a level that was not statistically different between the treatments, which might be attributed to the background level of the infested soil. The localization and pattern of colonization of SQR-21 on the root surface was examined in an in vitro experiment by following green fluorescent protein (gfp)-labeled SQR-21. The colonization of P. polymyxa SQR-21 was found to occur at any site on the roots, yet it was preferentially found in defined regions of the root tip and root bend. These results revealed that the BIO applied with the developed method suppressed Fusarium wilt by the promotion of SQR-21 colonization in the rhizosphere, which largely reduced the population of the pathogen. The findings also indicated that the method of nursery application of BIO satisfies the ecological requirements of the biocontrol products. [Copyright &y& Elsevier]

Abstract: Paenibacillus polymyxa can serve as a biocontrol agent with a broad host range, but knowledge of the possible contribution of root exudates to its colonization of the rhizosphere remains limited. In this experiment, we identified several organic acids in the root exudates of watermelon. Chemotaxis and swarming assays were performed to investigate the ability of these organic acids to induce the motility of P. polymyxa SQR-21. Oxalic acid, malic acid and citric acid were present in the root exudates but only the intermediate products in tricarboxylic acid cycle, i.e., malic acid and citric acid, could significantly induce motility in P. polymyxa SQR-21. The maximal inducing ability was obtained with malic acid. Values for malic acid were 3.9 and 1.5 times higher than the control in the chemotaxis assay and the swarming assay, respectively. An in vitro experiment further confirmed that these intermediate products in tricarboxylic acid cycle could promote recruitment to P. polymyxa SQR-21, thereby increasing the population in the rhizosphere. In conclusion, some of the organic acids secreted by roots could play an important role in root colonization of SQR-21. This finding contributes to our understanding of the interactions of bacteria and plants under natural conditions. [Copyright &y& Elsevier]

Abstract: The asymmetric traveling salesman problem (ATSP) appears in various applications. Although there are several heuristic approaches to its solution, the problem is still a difficult combinatorial optimization problem. This work proposes a novel hybrid approach specialized for the ATSP. The proposed method incorporates an improved genetic algorithm (IGA) and some optimization strategies that contribute to its effectiveness. In the IGA, both the crossover operation and the mutation operation are improved by selecting the optimum from a set of solutions. Three strategies: immigration, local optimization and global optimization are established based on several empirical optimization strategies to improve the evolution of the IGA. Computational experiments are conducted on 16 ATSP instances available in the TSPLIB (traveling salesman problem library). The comparative study shows that our proposed approach outperforms several other published algorithms. [Copyright &y& Elsevier]

C34H34CdN12O2S2, triclinic, P1̄, a = 9.6872(6) Å, b = 10.4523(7) Å, c = 10.8422(9) Å, α = 113.022(7)°, β = 96.919(6)°, γ = 104.526(6)°, Z = 1, V = 948.20(13) Å3, Rgt(F) = 0.0564, wRref(F2) = 0.1511, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Background and Aims: Understanding microbial compositions and functions in arable soils is crucial for effective agroecosystem management. While many studies have explored this topic, large-scale investigations are lacking, resulting in the absence of consistent and reliable patterns of communities and functions of soil microorganisms. Methods: To address this gap, we performed an integrated analysis of published sequencing data from the soils of three main arable fields: upland, paddy, and paddy-upland rotation. Results: Bacterial diversity (richness, Shannon) was highest in upland soils. Actinobacteria and Planctomycetes were enriched in upland soils, while Proteobacteria, Chloroflexi, and Nitrospirae preferred paddy and paddy-upland rotation soils. Bacteria in upland soils have a greater functional potential to decompose aromatic compounds, as well as for chitinolysis and ureolysis. Methanotrophy, methylotrophy, sulfur-related respiration, and most nitrogen metabolic processes were enriched in paddy fields. Bacteria in upland soils are characterized by increased dormancy potential and a faster response to resource input than those in paddy and paddy-upland rotation soils. Stochastic processes poorly contribute to the bacterial assembly in paddy soils, indicating strong environmental filtering due to anaerobic conditions. The spatial turnover in bacterial community composition was much faster than the functional potential, indicating high functional redundancy, especially in paddy soils. Edaphic factors were the major contributors to bacterial composition, whereas the cropland type influenced the predicted functions. Conclusions: Land use defines microbial composition, functional attributes, and ecological characteristics (e.g., dormancy potential, assembly processes, and functional redundancy). These findings deepen our knowledge of microbial biogeographic patterns in soils of agricultural ecosystems and provide new insights into sustainable cropland management. [ABSTRACT FROM AUTHOR]

The ongoing climate change on the Tibetan Plateau, leading to warming and precipitation anomalies, modifies phosphorus (P) cycling in alpine meadow soils. However, the interactions and cascading effects of warming and precipitation changes on the key "extracellular" and "intracellular" P cycling genes (PCGs) of bacteria are largely unknown for these P‐limited ecosystems. We used metagenomics to analyze the individual and combined effects of warming and altered precipitation on soil PCGs and P transformation in a manipulation experiment. Warming and increased precipitation raised Olsen‐P (bioavailable P, AP) by 13% and 20%, respectively, mainly caused by augmented hydrolysis of organic P compounds (NaOH‐Po). The decreased precipitation reduced soil AP by 5.3%. The richness and abundance of the PCGs' community in soils on the cold Tibetan plateau were more sensitive to warming than altered precipitation. The abundance of PCGs and P cycling processes decreased under the influence of individual climate change factors (i.e., warming and altered precipitation alone), except for the warming combined with increased precipitation. Pyruvate metabolism, phosphotransferase system, oxidative phosphorylation, and purine metabolism (all "intracellular" PCG) were closely correlated with P pools under climate change conditions. Specifically, warming recruited bacteria with the phoD and phoX genes, which encode enzymes responsible for phosphoester hydrolysis (extracellular P cycling), strongly accelerated organic P mineralization and so, directly impacted P bioavailability in alpine soil. The interactions between warming and altered precipitation profoundly influenced the PCGs' community and facilitated microbial adaptation to these environmental changes. Warming combined with increased precipitation compensated for the detrimental impacts of the individual climate change factors on PCGs. In conclusion, warming combined with rising precipitation has boosting effect on most P‐related functions, leading to the acceleration of P cycling within microbial cells and extracellularly, including mineralization and more available P release for microorganisms and plants in alpine soils. [ABSTRACT FROM AUTHOR]