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Abstract: Background: Hip fractures are always associated with a high postoperative mortality, the preoperative predictors for mortality have neither been well identified or summarised. This systematic review and meta-analysis was performed to identify the preoperative non-interventional predictors for mortality in hip fracture patients, especially focused on 1year mortality. Methods: Non-interventional studies were searched in Pubmed, Embase, Cochrane central database (all to February 26th, 2011). Only prospective studies and retrospective studies with prospective collected data were included. Qualities of included studies were assessed by a standardised scale previous reported for observational studies. The effects of individual studies were combined with the study quality score using a previous reported model of best-evidence synthesis. The hazard ratios of strong evidence predictors were combined only by high quality studies. Results: 75 included studies with 94 publications involving 64,316 patients were included and the available observations was a heterogeneous group. The overall inpatient or 1month mortality was 13.3%, 3–6months was 15.8%, 1year 24.5% and 2years 34.5%. There were strong evidence for 12 predictors, including advanced age, male gender, nursing home or facility residence, poor preoperative walking capacity, poor activities of daily living, higher ASA grading, poor mental state, multiple comorbidities, dementia or cognitive impairment, diabetes, cancer and cardiac disease. We also identified 7 moderate evidence and 12 limited evidence mortality predictors, and only the race was identified as the conflicting evidence predictor. Conclusion: Whilst there is no conclusive evidence of the preoperative predictors for mortality following hip fractures, special attention should be paid to the above 12 strong evidence predictors. Future researches were still needed to evaluate the effects of these predictors. [Copyright &y& Elsevier]

• Potential of fungi as bioindicators of water quality of the Mekong River is shown. • Hydro-chemical and fungal compositions exhibited variations across seasons and sites. • Deterministic processes suggested environmental filtering on some fungal communities. • Machine learning was used for water quality prediction with fungal abundance. • Abundance of certain fungal bins (e.g. Agaricomycetes) can classify water quality. Given their ecological importance, bioindicators are used for the assessment of the health of river ecosystems. This study explored the fungal compositions and the potential of fungal taxa as bioindicators for indicating the water quality of the Mekong River, as the use of fungal indicators of the Mekong River was not previously well characterized. The Mekong River exhibited dynamic variations in both physicochemical/hydrochemical properties and fungal communities according to seasons and locations. The results revealed the dominance of alkaline earth metal ions and weak acids in the water. The magnesium-bicarbonate water type was found in the dry season, but the water became the chloride-calcium type or mixed type of magnesium-bicarbonate and chloride-calcium in the rainy season at downstream sites. Fungal composition analysis revealed the dominance of Chytridiomycota in the dry season and intermediate periods, and Ascomycota and Basidiomycota in the rainy season. The fungal communities were influenced by stochastic and deterministic assembly processes, mainly homogeneous selection, heterogeneous selection, and dispersal limitation. The extent of environmental filtering implied that some fungal taxa were affected by environmental conditions, suggesting the possibility of identifying certain fungal taxa suitable for being bioindicators of water quality. Subsequently, machine learning with recursive feature elimination identified specific fungal bins mostly consisting of Agaricomycetes (mainly Polyporales, Agaricales , and Auriculariales), Dothideomycetes (mainly Pleosporales), Saccharomycetes (mainly Saccharomycetales), Chytridiomycota, and Rozellomycota as bioindicators that could predict ambient and irrigation water quality with high selectivity and sensitivity. These results thus promote the use of fungal indicators to assess the health of the river. [Display omitted] [ABSTRACT FROM AUTHOR]

• Stress-tolerance Methanosarcina dominates methane production in anaerobic digesters. • Thermodynamic, resource allocation, and labor division explain digester microbehavior. • Review of recent biostrategies for producing digestive products other than methane. • Multi-omics data integration facilitates the mining of microbial ecology. • Perspectives on developing synthetic consortia and customized databases. Microbially driven anaerobic digestion (AD) processes are of immense interest due to their role in the biovalorization of biowastes into renewable energy resources. The function-versatile microbiome, interspecies syntrophic interactions, and trophic-level metabolic pathways are important microbial components of AD. However, the lack of a comprehensive understanding of the process hampers efforts to improve AD efficiency. This study presents a holistic review of research on the microbial and metabolic "black box" of AD processes. Recent research on microbiology, functional traits, and metabolic pathways in AD, as well as the responses of functional microbiota and metabolic capabilities to optimization strategies are reviewed. The diverse ecophysiological traits and cooperation/competition interactions of the functional guilds and the biomanipulation of microbial ecology to generate valuable products other than methane during AD are outlined. The results show that AD communities prioritize cooperation to improve functional redundancy, and the dominance of specific microbes can be explained by thermodynamics, resource allocation models, and metabolic division of labor during cross-feeding. In addition, the multi-omics approaches used to decipher the ecological principles of AD consortia are summarized in detail. Lastly, future microbial research and engineering applications of AD are proposed. This review presents an in-depth understanding of microbiome-functionality mechanisms of AD and provides critical guidance for the directional and efficient bioconversion of biowastes into methane and other valuable products. [Display omitted] [ABSTRACT FROM AUTHOR]

• phzH gene regulates the corrosion rate of marine Pseudomonas aeruginosa. • phzH gene regulates the secretion of phenazine-1-carboxamide (PCN). • PCN affects the sessile cell count, which does not affect the corrosion tendency. • PCN damages the passive film by facilitating the release of hexavalent chromium. • EET mediated by PCN is the dominant factor to accelerate MIC. Microbiologically influenced corrosion (MIC) constantly occurs in water/wastewater systems, especially in marine water. MIC contributes to billions of dollars in damage to marine industry each year, yet the physiological mechanisms behind this process remain poorly understood. Pseudomonas aeruginosa is a representative marine electro-active bacterium, which has been confirmed to cause severe MIC on carbon steel through extracellular electron transfer (EET). However, little is known about how P. aeruginosa causes corrosion on stainless steel. In this study, the corrosivity of wild-type strain, phzH knockout, phzH complemented, and phzH overexpression P. aeruginosa mutants were evaluated to explore the underlying MIC mechanism. We found the accelerated MIC on 2205 duplex stainless steel (DSS) was due to the secretion of phenazine-1-carboxamide (PCN), which was regulated by the phzH gene. Surface analysis, Mott-Schottky test and H 2 O 2 measurement results showed that PCN damaged the passive film by forming H 2 O 2 to oxidize chromium oxide to soluble hexavalent chromium, leading to more severe pitting corrosion. The normalized corrosion rate per cell followed the same order as the general corrosion rate obtained under each experimental condition, eliminating the influence of the total amount of sessile cells on corrosion. These findings provide new insight and are meaningful for the investigation of MIC mechanisms on stainless steel. The understanding of MIC can improve the sustainability and resilience of infrastructure, leading to huge environmental and economic benefits. [Display omitted] [ABSTRACT FROM AUTHOR]

The influence of outward extracellular electron transfer (EET) of Pseudomonas aeruginosa in accelerating corrosion of 304 stainless steel was investigated. With less NO 3 − available as electron acceptor, P. aeruginosa biofilm accelerated the pitting corrosion. The ICP-MS and XPS results indicated that P. aeruginosa promoted the bioreductive dissolution of iron oxides in the passive film of stainless steel. Using in situ scanning electrochemical microscopy, we established a relationship between this accelerated deterioration of the passive film and the EET process mediated by the conversion of the redox states of pyocyanin secreted by P. aeruginosa. • P. aeruginosa promotes the bioreductive dissolution of iron oxides in passive film. • The conversion of the redox state of PYO electron shuttle is monitored by SECM. • P. aeruginosa accelerates MIC of the stainless steel via outward EET. [ABSTRACT FROM AUTHOR]

Although ferric iron in extracellular polymeric substances (EPS) was believed to be pivotal in bioleaching, the real existing form of ferric iron in EPS has remained poorly understood. In this study, whole cells of Acidithiobacillus ferrooxidans were used to study the composition and properties of EPS. The components sugars, proteins and uronic acids could be extracted from cells rich in EPS. Four distinct surface functional groups were characterized on the bacterial surfaces by the fitting of titration data. Subsequently, these functional groups were confirmed as carboxyl groups, phosphoryl groups, thiol groups, and amine groups by combining FTIR and XPS. However, with the help of modeling results and FTIR, these functional groups failed to dissociate protons in a strong acidic environment. The protonated functional groups could unlikely complex ferric iron according to the site-specific surface complexation theory. Besides, the isolated EPS could not sharply reduce the concentration of free ferric ions, and the ferric iron could be removed by washing the cell surfaces with HClO 4. These results indicate that there is no strong chemical interaction between bacteria and ferric iron. This study suggests a weak interaction of ferric iron with the EPS of A. ferrooxidans , and gives some deeper insight into the microenvironment of EPS. • Extracellular polymeric substances (EPS) of Acidithiobacillus ferrooxidans could not complex Fe3+ in an acidic environment. • Whole cells with abundant EPS were used to study the properties of EPS. • Carboxyl groups, phosphoryl groups, thiol groups, and amine groups were characterized on the bacterial surface. • These functional groups in EPS were all protonated under a strong acidic environment. [ABSTRACT FROM AUTHOR]

Abstract: Scheelite-type Eu3+-doped CaMoO4 red phosphor with uniform micro-assemblies has been successfully synthesized via a facile hydrothermal method at 120°C for 10h. The Eu3+-doped CaMoO4 microstructures were assembled by small nanostructures and the morphology of materials was found to be manipulated by dropping different alkalis into the stock solution for the first time. The structure, morphology, and luminescent property were characterized and investigated by techniques of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL). The luminescent investigations confirmed that the Eu3+ ions have been effectively doped into CaMoO4 nanostructures. The successfully achieved Eu3+-doped CaMoO4 nanostructures will be potential in technological applications on near UV chip-based white light emitting diode (WLED). [Copyright &y& Elsevier]

• Effects of microbial types and diversity on chalcopyrite bioleaching were studied. • Community with more sulfur oxidizers and high diversity showed high Cu recovery. • Microbial types showed greater influences on mineral dissolution than biodiversity. • A. caldus enhanced CuFeS 2 extraction greatly by regulating physicochemical factors. Six artificial communities with different function or biodiversity were reconstructed by six typical bioleaching species for chalcopyrite leaching. Absence of sulfur oxidizers in communities significantly reduced copper extraction rates, and low diversity communities also exhibited slightly poor bioleaching performances. The variations of pH, redox potential, ferrous and copper ions indicated that the community with both sulfur oxidizers and high diversity showed fast adaptation to the environment and rapid dissolution of chalcopyrite. Integrated analysis of mineralogical and microbial parameters demonstrated that functional types of microorganisms made more contributions in mediating chalcopyrite dissolution than microbial diversity. Further correlation analysis between microbial types and chalcopyrite dissolution performances showed that sulfur oxidizers, especially Acidithiobacillus caldus , could greatly accelerate chalcopyrite dissolution by regulating solution physicochemical factors, such as redox potential and pH. This study provided a theoretical basis for improving bioleaching efficiency by balancing microbial functional types and biodiversity. [ABSTRACT FROM AUTHOR]

• The phzM and phzS genes regulate the production of electron mediator PYO. • Deletion of the phzM and phzS genes reduce the MIC by P. aeruginosa. • Organic carbon starvation tests confirm the role of PYO in the accelerated EET. In Pseudomonas aeruginosa , phzM and phzS genes encode two enzymes that convert phenazine‑1‑carboxylate to pyocyanin (PYO), which is an efficient mediator for EET. Herein, an aerobic P. aeruginosa mutant strain with phzM and phzS genes knockout was used to confirm that phzM and phzS genes regulate EET-MIC of X80 carbon steel. The inhibition efficiency of MIC by mutant strain reached ∼48 %, demonstrating that MIC was considerably suppressed since the mutant strain was no longer capable of producing sufficient PYO. When organic carbon was deficient, P. aeruginosa could utilise iron as an electron donor and caused more severe corrosion via EET. [ABSTRACT FROM AUTHOR]