Abstract
In order to obtain the optimal conditions for ammonia nitrogen (AN) wastewater treatment by bio filter (BF), the effects of ratio of carbon to nitrogen (C/N), pH, and hydraulic load (HL) on ...the AN degradation were studied by Response Surface Methodology (RSM). Central Composite Design (CCD) experiments were conducted, and the response of the AN removal rates were fitted to a second-order polynomial model. The analysis of variance showed that the model was accurate and reliable. Through model fitting, the optimal condition for AN removal was: C/N of 18.95, pH of 7.78, and HL of 1.04 d
−1
. The maximum AN removal rate predicted by the model was 91.90%, accorded with the experimental verification value of 91.37% under the optimal condition. The research provided valuable demonstration for optimizing process parameters on AN removal in BF.
Taking rural dispersed sewage for research objects, the treatment effect and microbial community structure characteristics of a bio filter (BF) reactor was studied. At fixed time and location, the ...removal efficiencies of common pollutants were investigated. By using high-throughput sequencing method, the heterogeneities of microbial community structure in fillers and plant roots were analyzed. The results showed that the average annual removal rates of CODCr, NH3–N, TN, and TP by the BF were 83.10 %, 65.67 %, 60.25 %, and 80.32 % respectively, and the effluent could reach the first grade of the water pollutant discharge standard of rural sewage treatment facility (DB51/2626-2019). During the sewage treatment process, Scindapsus could effectively establish complex and stable microbial communities, and could better degrade pollutants, especially nitrogen removal. The dominant microbial communities were more than 11 phyla and 19 classes. At the genus level, the dominant bacteria included Nitrospira, Arthrobacter, Rhodoplanes, etc.
•Demonstrating the dominant role of plants in pollutant degradation of Bio Filter.•Revealing the relationship between purification effect and microbial community structure in the Bio Filter.
Owing to the characteristics of mimicking human skin’s function and transmitting sensory signals, electronic skin (e-skin), as an emerging and exciting research field, has inspired tremendous efforts ...in the biomedical field. However, it is frustrating that most e-skins are prone to bacterial infections, resulting a serious threat to human health. Therefore, the construction of e-skin with an integrated perceptual signal and antibacterial properties is highly desirable. Herein, the dynamic supramolecular hydrogel was prepared through a freezing/thawing method by cross-linking the conductive graphene (G), biocompatible polyvinyl alcohol (PVA), self-adhesive polydopamine (PDA), and in situ formation antibacterial silver nanoparticles (AgNPs). Having fabricated the hierarchical network structure, the PVA–G–PDA–AgNPs composite hydrogel with a tensile strength of 1.174 MPa and an elongation of 331% paves way for flexible e-skins. Notably, the PVA–G–PDA–AgNPs hydrogel exhibits outstanding antibacterial activity to typical pathogenic microbes (e.g., Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus), which effectively prevents bacterial infections that harm human health. With self-adhesiveness to various surfaces and excellent conductivity, the PVA–G–PDA–AgNPs composite hydrogel was used as strain sensors to detect a variety of macroscale and microscale human motions successfully. Meanwhile, the excellent rehealing property allows the hydrogel to recycle as a new sensor to detect large-scale human activities or tiny movement. Based on these remarkable features, the antibacterial, self-adhesive, recyclable, and tough conductive composite hydrogels possess the great promising application in biomedical materials.
The large-scale commercial application of phase change materials (PCMs) was seriously limited by the leakage, poor heat storage capacity and slow thermal response behavior. To address these issues, ...stearic acid/graphene oxide-attapulgite aerogel (SA/HGA-ATP) shape-stabilized PCMs were fabricated via hydrothermal method. The morphology, structural characteristics, thermal properties were determined and the effects of ATP percentage on the thermal properties of confined SA were studied synchronously. The nanofibers of ATP intercalated among GO sheets via grafting modification and formed fiber-bridging 3D-network. Due to the enhanced loading interspaces and suppressed volumetric shrinkage of hybrid matrix, SA/HGA-ATP exhibited excellent thermal energy storage capacity (190.9 J g−1) and ultra-high SA contents (approx. 98 wt%) without leakage. The intercalated nanofibers sheltered the oxygen-containing groups of matrices, leading to the promotion of thermal energy storage performance with increase of ATP contents. Besides, the as-prepared PCMs displayed outstanding thermal response behavior because the interconnected and fiber-bridged matrices provided continuous thermal transfer pathway. Due to the protection of matrix, the composite PCMs also exhibited superior structure stability and incomparable thermal energy storage/release reliability. Considering the outstanding thermal-physical properties and low-cost of ATP, the SA/HGA-ATP has the potential to be applied in the fields of thermal energy storage, conversion and utilization.
•Three-dimensional matrices with fiber-bridged porous structure were fabricated.•Introduction of attapulgite nanofibers is benefit for serving more loading spaces.•The constructed fiber-bridges provide continuous thermal-transfer pathway.•The mass fraction of loaded stearic acid is as high as 98% without seepage.
To verify the roles of GltS, GltP, and GltI in
tolerance and pathogenicity, we quantified and compared the relative abundance of
,
, and
in log-phase and stationary-phase
and constructed their ...knockout mutant strains in
BW25113 and uropathogenic
(UPEC) separately, followed by analysis of their abilities to tolerate antibiotics and stressors, their capacity for adhesion to and invasion of human bladder epithelial cells, and their survival ability in mouse urinary tracts. Our results showed that
,
, and
transcripts were higher in stationary phase
than in log-phase incubation. Furthermore, deletion of
,
, and
genes in
BW25113 results in decreased tolerance to antibiotics (levofloxacin and ofloxacin) and stressors (acid pH, hyperosmosis, and heat), and loss of
,
, and
in uropathogenic
UTI89 caused attenuated adhesion and invasion in human bladder epithelial cells and markedly reduced survival in mice. The results showed the important roles of the glutamate transporter genes
,
, and
in
tolerance to antibiotics (levofloxacin and ofloxacin) and stressors (acid pH, hyperosmosis, and heat) in vitro and in pathogenicity in mouse urinary tracts and human bladder epithelial cells, as shown by reduced survival and colonization, which improves our understanding of the molecular mechanisms of bacterial tolerance and pathogenicity.
The fundamental component of the ecological compensation system, as well as the crucial basis for its efficient functioning, is calculating the ecological compensation amount and establishing the ...ecological compensation standard. This study integrates the ecological footprint with natural capital monetization and other methods by introducing a natural capital accounting system. From the standpoint of natural capital supply and demand, it also builds an accounting framework for ecological compensation standards that is standardized, dynamic, and regionally differentiated while taking local socioeconomic aspects into account. We determined the amount of ecological compensation by using Xinjiang as the research object and calculating and analyzing the features of regional and temporal changes in the monetary and physical quantities of natural capital in Xinjiang from 2010 to 2020. The findings show that from 2010 to 2020, Xinjiang’s ecological footprint increased by 1.26 times in physical terms and 1.21 times in monetary terms and that its ecological carrying capacity increased by 4.13% in physical terms and 9.42% in monetary terms. The ecological deficit continues to grow in physical and monetary terms, with a per capita ecological deficit in 2020 of 19.92 s-nha/cap and 70,100 CNY/cap in physical and monetary terms, respectively. The amount of ecological compensation required to be paid in Xinjiang increased from CNY 5659 million to CNY 10,259 million, and the per capita ecological compensation payment standard increased from 259.42 CNY/cap/yr to 396.11 CNY/cap/yr. In summary, Xinjiang’s natural capital supply is insufficient to meet the demand for consumption, and the ecological deficit is growing with time, necessitating the payment of ecological compensation. The study’s results lay the foundation for formulating and implementing ecological compensation policies in Xinjiang and provide theoretical support for constructing ecological civilization in Xinjiang. In addition, the ecological compensation accounting framework constructed in this study organically integrates natural capital theory, ecosystem services, and socioeconomic influencing factors, which enriches the methodology of accounting for ecological compensation standards, and, at the same time, can be used as a paradigm of a dynamic and equitable ecological compensation accounting framework to further promote its use at different scales and regions.
A meta‐analysis study to assess the effect of ultrasound‐supported wound debridement (USSD) in subjects with diabetic foot ulcer (DFU). A comprehensive literature examination till January 2023 was ...implemented and 1873 linked studies were appraised. The picked studies contained 577 subjects with DFUs in the studies' baseline, 282 of them were using USSD, 204 were using standard care, and 91 were using a placebo. Odds ratio (OR) in addition to 95% confidence intervals (CIs) were used to calculate the consequence of USSD in subjects with DFUs by the dichotomous styles and a fixed or random effect model. The USSD applied to DFU caused a significantly higher wound healing rate compared with the standard care (OR, 3.08; 95% CI, 1.94–4.88, P < .001) with no heterogeneity (I2 = 0%) and the placebo (OR, 7.61; 95% CI, 3.11–18.63, P = .02) with no heterogeneity (I2 = 0%). The USSD applied to DFUs caused a significantly higher wound healing rate compared with the standard care and the placebo. Though precautions should be taken when commerce with the consequences as all of the picked studies for this meta‐analysis was with low sample sizes.
Persisters are metabolically quiescent phenotypic variants of the wild type that are tolerant to cidal antibiotics, and the mechanisms of persister formation and survival are complex and not ...completely understood. To identify genes involved in persistence to tosufloxacin, which has higher activity against persisters than most other quinolones, we screened the
KEIO mutant library using a different condition from most persister mutant screens (6 h) with a longer exposure of 18 h with tosufloxacin. We identified 18 mutants (
, and
) that failed to form tosufloxacin tolerant persisters. Among them, g
, and
are unique genes involved in
persistence to tosufloxacin which have not been reported before. Furthermore, deletion mutants in genes coding periplasmic proteins (
, and
) had more defect in persistence to tosufloxacin than the other identified mutants, with
and
mutants being the most prominent. The "deep" persister phenotype of
and
mutants was further confirmed both
and
. Compared with the wild type strain
BW25113
, the persister phenotype of the
and
mutants was decreased more than 100-1,000-fold in persistence to various antibiotics, acidic, hyperosmotic and heat conditions. In addition, in both stationary phase bacteria and biofilm bacteria infection mouse models, the
mutants had lower survival and persistence than the parent uropathogenic strain UTI89, suggesting that the
identified persister mechanisms (
and
) are operative and valid for
persistence. Our findings provide new insight into the mechanisms of persister formation and maintenance under tosufloxacin and will likely provide novel therapeutic and vaccine targets for developing more effective treatment and prevention of persistent
infections.
To verify the roles of GltS, GltP, and GltI in E. coli tolerance and pathogenicity, we quantified and compared the relative abundance of gltS, gltP, and gltI in log-phase and stationary-phase E. coli ...and constructed their knockout mutant strains in E. coli BW25113 and uropathogenic E. coli (UPEC) separately, followed by analysis of their abilities to tolerate antibiotics and stressors, their capacity for adhesion to and invasion of human bladder epithelial cells, and their survival ability in mouse urinary tracts. Our results showed that gltS, gltP, and gltI transcripts were higher in stationary phase E. coli than in log-phase incubation. Furthermore, deletion of gltS, gltP, and gltI genes in E. coli BW25113 results in decreased tolerance to antibiotics (levofloxacin and ofloxacin) and stressors (acid pH, hyperosmosis, and heat), and loss of gltS, gltP, and gltI in uropathogenic E. coli UTI89 caused attenuated adhesion and invasion in human bladder epithelial cells and markedly reduced survival in mice. The results showed the important roles of the glutamate transporter genes gltI, gltP, and gltS in E. coli tolerance to antibiotics (levofloxacin and ofloxacin) and stressors (acid pH, hyperosmosis, and heat) in vitro and in pathogenicity in mouse urinary tracts and human bladder epithelial cells, as shown by reduced survival and colonization, which improves our understanding of the molecular mechanisms of bacterial tolerance and pathogenicity.
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