A growing body of evidence suggests that microbial α-diversity (local species richness) may have positive effects on ecosystem function. However, less attention has been paid to β-diversity (the ...variation among local microbial assemblages). Here we studied the impact of microbial α-diversity on stochastic/deterministic microbial community assembly processes, which are related to β-diversity, and the consequences for community function. Bacterial communities differing in α-diversity were generated and their structures and potential community functional traits were inferred from DNA sequencing. Phylogenetic null modeling analysis suggests that stochastic assembly processes are dominant in high-diversity communities. However, in low-diversity communities, deterministic assembly processes are dominant, associating with the reduction of specialized functions that are correlated with specific bacterial taxa. Overall, we suggest that the low-diversity-induced deterministic community assembly processes may constrain community functions, highlighting the potential roles of specialized functions in community assembly and in generating and sustaining the function of soil ecosystems.
Accurate estimation for the state of charge (SOC) is one of the most important aspects of a battery management system (BMS) in electric vehicles (EVs) as it provides drivers with the EVs' remaining ...range. However, it is difficult to get an accurate SOC, because its value cannot be directly measured and is affected by various factors, such as the operating temperature, current rate and cycle number. In this paper, a modified equivalent circuit model is presented to include the impact of different current rates and SOCs on the battery internal resistance, and the impact of different temperatures and current rates on the battery capacity. Besides, a linear–averaging method is presented to calculate the internal resistance and practical capacity correction factors according to data collected from the experimental bench and saved as look-up tables. The unscented Kalman filter (UKF) algorithm is then introduced to estimate the SOC according to the presented model. Experiments based on actual urban driving cycles are carried out to evaluate the performance of the presented method by comparing with two existed methods. Experimental results show that the proposed method can reduce the computation cost and improve the SOC estimation accuracy simultaneously.
•A modified equivalent circuit model is presented.•A linear-averaging method is presented to compute correction factors.•The UKF algorithm for SOC estimation based on the presented model is introduced.•Performance of the proposed method is verified by comparison results.
The relationship between biodiversity and soil microbiome stability remains poorly understood. Here, we investigated the impacts of bacterial phylogenetic diversity on the functional traits and the ...stability of the soil microbiome. Communities differing in phylogenetic diversity were generated by inoculating serially diluted soil suspensions into sterilized soil, and the stability of the microbiome was assessed by detecting community variations under various pH levels. The taxonomic features and potential functional traits were detected by DNA sequencing.
We found that bacterial communities with higher phylogenetic diversity tended to be more stable, implying that microbiomes with higher biodiversity are more resistant to perturbation. Functional gene co-occurrence network and machine learning classification analyses identified specialized metabolic functions, especially "nitrogen metabolism" and "phosphonate and phosphinate metabolism," as keystone functions. Further taxonomic annotation found that keystone functions are carried out by specific bacterial taxa, including Nitrospira and Gemmatimonas, among others.
This study provides new insights into our understanding of the relationships between soil microbiome biodiversity and ecosystem stability and highlights specialized metabolic functions embedded in keystone taxa that may be essential for soil microbiome stability. Video abstract.
Improving the yield of rumen microbial protein (MCP) has significant importance in the promotion of animal performance and the reduction of protein feed waste. The amount of energy supplied to rumen ...microorganisms is an important factor affecting the amount of protein nitrogen incorporated into rumen MCP. Substrate-level phosphorylation (SLP) and electron transport phosphorylation (ETP) are two major mechanisms of energy generation within microbial cells. However, the way that energy and protein levels in the diet impact the energy productivity of the ruminal microbiome and, thereafter, rumen MCP yields is not known yet. In present study, we have investigated, by animal experiments and metagenome shotgun sequencing, the effects of energy-rich and protein-rich diets on rumen MCP yields, as well as SLP-coupled and ETP-coupled energy productivity of the ruminal microbiome. We have found that an energy-rich diet induces a significant increase in rumen MCP yield, whereas a protein-rich diet has no significant impacts on it. Based on 10 reconstructed pathways related to the energy metabolism of the ruminal microbiome, we have determined that the energy-rich diet induces significant increases in the total abundance of SLP enzymes coupled to the nicotinamide adenine dinucleotide (NADH) oxidation in the glucose fermentation and F-type ATPase of the electron transporter chain, whereas the protein-rich diet has no significant impact in the abundance of these enzymes. At the species level, the energy-rich diet induces significant increases in the total abundance of 15 ETP-related genera and 40 genera that have SLP-coupled fermentation pathways, whereas the protein-rich diet has no significant impact on the total abundance of these genera. Our results suggest that an increase in dietary energy levels promotes rumen energy productivity and MCP yield by improving levels of ETP and SLP coupled to glucose fermentation in the ruminal microbiome. But, an increase in dietary protein level has no such effects.
The rumen barriers, constituted by the microbial, physical and immune barrier, prevent the transmission of pathogens and toxins to the host tissue in the maintenance of host-microbe homeostasis. ...Ruminal short-chain fatty acids (SCFAs), which are the important signaling molecules derived from the rumen microbiota, regulate a variety of physiological functions of the rumen. So far, how the ruminal SCFAs regulate the function of rumen barriers is unclear. By the combined methods of transcriptome sequencing, 16S
rRNA
gene sequencing, and metagenome shotgun sequencing, we have investigated the regulatory effects of ruminal SCFAs on the functions of rumen barriers, by determining the composition and functions of epimural microbiota and on the structure and immunity of the rumen epithelium in goats receiving a 10% (LC group), 35% (MC group), or 65% concentrate diet (HC group). We found that, when the dietary concentrate shifted from 10 to 35%, the increase of total SCFA is associated with the diversification of epimural microbiota and the diversity of its gene pool. Within the microbial community, the relative abundance of genera
Sphingobium
,
Acinetobacter
, and
Streptococcus
increase mostly. Meantime, the signals on pathways concerning the mechanical connections and growth homeostasis in the rumen epithelium were upregulated. Under these conditions, the responses of immune components in the rumen epithelium decrease. However, when the dietary concentrate shifted from 35 to 65%, the increase of acetate and reduction of pH decrease the diversity of epimural microbiota and the diversity of its gene pool. Within the microbial community, the relative abundance of genera
Sphingobium
,
Acinetobacter
, and
Streptococcus
significantly decrease. Concomitantly, the signals on pathways concerning the cell growth and tight junction disruption were upregulated, while the signals on pathways concerning paracellular permeability were downregulated. Under these conditions, the signals on the pathways relating to the immune components increase. Our data thus indicates that diet-SCFA axis maintains the host-microbe homeostasis via promoting the diversification of epimural microbiota and maintaining the integrity of rumen epithelium in healthy animals, while via enhancing the activities of immune barrier in animal with lower rumen pH.
Critical cytotoxicity evaluation of pharmaceuticals is necessary for the clinical practice of chemotherapy. To quantitatively evaluate cell viability, currently there are two main types of sensitive ...methods including real-time cell analysis (RTCA) and CCK-8 assay, in which RTCA records electrochemical signal changes around an incubated cell, whereas CCK-8 is based on the colorimetric method. Despite the different detection principles adopted for the cytotoxicity assessment, the comparison of the two methods in terms of the application scope is lacking. In this study, comparison studies were conducted between the RTCA and CCK-8 assays using anticancer drugs including doxorubicin hydrochloride, curcumin, irinotecan (CPT-11), taxol, and oxaliplatin, which are classified into two groups of drug molecules in the absence and presence of additives. The cytotoxicity evaluation of these drugs on cancer cells revealed that the physicochemical properties of drug formulations such as optical and electrochemical properties are closely linked with the readout of cytotoxic methods. The experimental results suggested that the preselection of cytotoxic assay is critical for the quantitative measurement of cytotoxicity of anticancer drugs, which is of clinical importance for their therapeutic usage.
The state of charge (SOC) is important for the safety and reliability of battery operation since it indicates the remaining capacity of a battery. However, as the internal state of each cell cannot ...be directly measured, the value of the SOC has to be estimated. In this paper, a novel method for SOC estimation in electric vehicles (EVs) using a nonlinear observer (NLO) is presented. One advantage of this method is that it does not need complicated matrix operations, so the computation cost can be reduced. As a key step in design of the nonlinear observer, the state–space equations based on the equivalent circuit model are derived. The Lyapunov stability theory is employed to prove the convergence of the nonlinear observer. Four experiments are carried out to evaluate the performance of the presented method. The results show that the SOC estimation error converges to 3% within 130 s while the initial SOC error reaches 20%, and does not exceed 4.5% while the measurement suffers both 2.5% voltage noise and 5% current noise. Besides, the presented method has advantages over the extended Kalman filter (EKF) and sliding mode observer (SMO) algorithms in terms of computation cost, estimation accuracy and convergence rate.
•A novel method for SOC estimation using a nonlinear observer is presented.•State equations are derived from the first-order RC equivalent circuit model.•The observer for SOC estimation is designed and its convergence is proved.•The new method has merits in computation cost, accuracy and convergence rate.
Abstract To systematically evaluate the intervention effect of music therapy on anxiety and depression in breast cancer patients. Randomised controlled trial (RCT) on music therapy for anxiety and ...depression in breast cancer patients was searched from 7 major databases, PubMed, Embase, the Cochrane Library, WOS, CNIC, Wanfang, and Wipro, spanning the period of library construction to 23 October 2023, and the literature screening of music therapy for anxiety or depression in breast cancer patients was carried out by 2 experimentalists, each of whom conducted a literature screening RCT independently of the other anxiety or depression in a RCT. Methodological quality was evaluated using the PEDro scale; GRADE profiler software for quality of evidence; and RevMan 5.4 was used for effect size merging and forest plots; publication bias tests and sensitivity analyses were performed using Stata 17.0; and standardized mean difference (SMD) and 95% CI were used as the effect statistics. A total of 13 RCTs with 1326 subjects (aged 18–70 years) were included in the literature, with a mean PEDro score of 6.8, and the literature was overall of good methodological quality. Meta-analysis showed that music therapy improved anxiety in breast cancer patients (841 cases), with a combined effect size (SMD = − 0.82, 95% CI − 1.03, − 0.61 and P < 0.001); and improved depression in breast cancer patients (387 cases) with a combined effect size (SMD = − 0.76, 95% CI − 1.15, − 0.38, P < 0.001). Subgroup analyses showed that music intervention with off-site music (757 cases) and music choice of non-self-selected music (537 cases) had the best effect on anxiety improvement, with corresponding combined effect sizes (SMD = − 0.88, P < 0.001; SMD = − 0.83, P < 0.001), respectively; followed by an intervention length of < 30 min (589 cases), a frequency of 2 times/day (382 cases), and intervention period of 2–3 weeks (101 cases) had the best effect on anxiety improvement, and the corresponding combined effect sizes were (SMD = − 0.80, P < 0.001; SMD = − 0.91, P < 0.001; SMD = − 1.02, P < 0.001), respectively; and the music selection was the choice of one's own favourite music among the expert recommendations (219 cases) (270 cases) had the best effect on the improvement of depressed mood, with combined effect sizes of (SMD = − 1.15, P < 0.001; SMD = − 0.71, P < 0.001) and music with an intervention duration of 30 min (287 cases), an intervention frequency of 1 time/day (348 cases), and an intervention period of 2–4 weeks (120 cases), respectively, with corresponding combined effect sizes of (SMD = − 0.75, P < 0.001; SMD = − 0.86, P < 0.001; SMD = − 1.06, P < 0.001), respectively. Music therapy can improve anxiety and depression in breast cancer patients, and the level of evidence is moderate. Although the heterogeneity between studies is high, which may lead to bias in the results, we explored the source of heterogeneity through subgroup and sensitivity analyses, providing a good evidence-based basis for clinical practice. The heterogeneity of anxiety and depression was explored by subgroup analysis, with anxiety due to music duration and music cycle; and depression due to intervention cycles and music duration. Sensitivity analyses also identified music duration and music cycle as contributing to the heterogeneity. Also, this study has some limitations since the included literature did not take into account the duration of the disease, education, and family economic status and did not categorize the age stages. This study found that music therapy improves anxiety and depression in breast cancer patients and the results can be used as a basis for clinical practice and researcher enquiry. This research has been registered on the INPLASY platform ( https://inplasy.com/contact/ ) under the number: INPLASY2023100057.
Chemotaxis, the ability of motile bacteria to direct their movement in gradients of attractants and repellents, plays an important role during the rhizosphere colonization by rhizobacteria. The ...rhizosphere is a unique niche for plant–microbe interactions. Root exudates are highly complex mixtures of chemoeffectors composed of hundreds of different compounds. Chemotaxis towards root exudates initiates rhizobacteria recruitment and the establishment of bacteria–root interactions. Over the last years, important progress has been made in the identification of root exudate components that play key roles in the colonization process, as well as in the identification of the cognate chemoreceptors. In the first part of this review, we summarized the roles of representative chemoeffectors that induce chemotaxis in typical rhizobacteria and discussed the structure and function of rhizobacterial chemoreceptors. In the second part we reviewed findings on how rhizobacterial chemotaxis and other root–microbe interactions promote the establishment of beneficial rhizobacteria-plant interactions leading to plant growth promotion and protection of plant health. In the last part we identified the existing gaps in the knowledge and discussed future research efforts that are necessary to close them.
PDF
