Boosting Hydrogen Evolution Reaction by Phase Engineering and Phosphorus Doping on Ru/P-TiO2.

Synergistic optimization of the elementary steps of water dissociation and hydrogen desorption for the hydrogen evolution reaction (HER) in alkaline media is a challenge. Herein, the Ru cluster anchored on a trace P-doped defective TiO2 substrate (Ru/P-TiO2 ) was synthesized as an electrocatalyst for the HER; it exhibited a commercial Pt/C-like geometric activity and an excellent mass activity of 9984.3 mA mgRu -1 at -0.05 V vs. RHE, which is 34.3 and 18.7 times higher than that of Pt/C and Ru/TiO2 , respectively. Experimental and theoretical studies indicated that using a rutile-TiO2 -crystal-phase substrate enhanced the HER activity more than the anatase phase. Rich surface oxygen vacancies on rutile-TiO2 facilitated the adsorption and dissociation of water, while the partial substitution of Ti4+ with P5+ enhanced H2 generation by facilitating hydrogen spillover from the Ru site to the surface P site, synergistically enhancing the HER activity.

Effect of Different Proportions of Three Microbial Agents on Ammonia Mitigation during the Composting of Layer Manure.

Odor emissions represent one of the important issues of aerobic composting. The addition of microbial agents to compost is an important method for solving this problem, but this process is often unstable when a single microbial agent is added to the compost. Therefore, in this study, five treatments comprising different proportions of Bacillus stearothermophilus, Candida utilis, and Bacillus subtilis were tested to determine the best combination of the three microbial agents for ammonia reduction, as follows: control group (CK), 2:1:1 (A), 1:1:2 (B), 1:2:1 (C), and 1:1:1 (D). Compared with the CK group, the A, B, C, and D groups reduced ammonia emissions by 17.02, 9.68, 53.11, and 46.23%, respectively. The total ammonia emissions were significantly lower in C and D than in CK (p < 0.05). These two treatment groups had significantly increased nitrate nitrogen concentrations and decreased pH values and ammonium nitrogen concentrations (p < 0.05). Throughout the composting process, the total bacterial number was significantly higher in C and D than in CK (p < 0.05). Therefore, it is likely that B. stearothermophilus, C. utilis, and B. subtilis compounded from 1:2:1 (C) to 1:1:1 (D) reduced the ammonia emissions due to (1) a reduction in the pH and (2) the promotion of the growth of ammonia-oxidizing bacteria and the conversion of ammonium nitrogen to nitrate nitrogen. This study provides a theoretical basis and technical support for the odor problem of layer manure compost and promotes the development of composting technology.

A microfluidic microalgae detection system for cellular physiological response based on an object detection algorithm.

The composition of species and the physiological status of microalgal cells serve as significant indicators for monitoring marine environments. Symbiotic with corals, Symbiodiniaceae are more sensitive to the environmental response. However, current methods for evaluating microalgae tend to be population-based indicators that cannot be focused on single-cell level, ignoring potentially heterogeneous cells as well as cell state transitions. In this study, we proposed a microalgal cell detection method based on computer vision and microfluidics, which combined microscopic image processing, microfluidic chip and convolutional neural network to achieve label-free, sheathless, automated and high-throughput microalgae identification and cell state assessment. By optimizing the data import, training process and model architecture, we solved the problem of identifying tiny objects at the micron scale, and the optimized model was able to perform the tasks of cell multi-classification and physiological state assessment with more than 95% mean average precision. We discovered a novel transition state and explored the thermal sensitivity of three clades of Symbiodiniaceae, and discovered the phenomenon of cellular heat shock at high temperatures. The evolution of the physiological state of Symbiodiniaceae cells is very important for directional cell evolution and early warning of coral ecosystem health.

Label-free spatiotemporal decoding of single-cell fate via acoustic driven 3D tomography.

Label-free three-dimensional imaging plays a crucial role in unraveling the complexities of cellular functions and interactions in biomedical research. Conventional single-cell optical tomography techniques offer affordability and the convenience of bypassing laborious cell labelling protocols. However, these methods are encumbered by restricted illumination scanning ranges on abaxial plane, resulting in the loss of intricate cellular imaging details. The ability to fully control cellular rotation across all angles has emerged as an optimal solution for capturing comprehensive structural details of cells. Here, we introduce a label-free, cost-effective, and readily fabricated contactless acoustic-induced vibration system, specifically designed to enable multi-degree-of-freedom rotation of cells, ultimately attaining stable in-situ rotation. Furthermore, by integrating this system with advanced deep learning technologies, we perform 3D reconstruction and morphological analysis on diverse cell types, thus validating groups of high-precision cell identification. Notably, long-term observation of cells reveals distinct features associated with drug-induced apoptosis in both cancerous and normal cells populations. This methodology, based on deep learning-enabled cell 3D reconstruction, charts a novel trajectory for groups of real-time cellular visualization, offering promising advancements in the realms of drug screening and post-single-cell analysis, thereby addressing potential clinical requisites.

Computer vision meets microfluidics: a label-free method for high-throughput cell analysis.

In this paper, we review the integration of microfluidic chips and computer vision, which has great potential to advance research in the life sciences and biology, particularly in the analysis of cell imaging data. Microfluidic chips enable the generation of large amounts of visual data at the single-cell level, while computer vision techniques can rapidly process and analyze these data to extract valuable information about cellular health and function. One of the key advantages of this integrative approach is that it allows for noninvasive and low-damage cellular characterization, which is important for studying delicate or fragile microbial cells. The use of microfluidic chips provides a highly controlled environment for cell growth and manipulation, minimizes experimental variability and improves the accuracy of data analysis. Computer vision can be used to recognize and analyze target species within heterogeneous microbial populations, which is important for understanding the physiological status of cells in complex biological systems. As hardware and artificial intelligence algorithms continue to improve, computer vision is expected to become an increasingly powerful tool for in situ cell analysis. The use of microelectromechanical devices in combination with microfluidic chips and computer vision could enable the development of label-free, automatic, low-cost, and fast cellular information recognition and the high-throughput analysis of cellular responses to different compounds, for broad applications in fields such as drug discovery, diagnostics, and personalized medicine.

Effects of Music and White Noise Exposure on the Gut Microbiota, Oxidative Stress, and Immune-Related Gene Expression of Mice.

The microbiota in gastrointestinal tracts is recognized to play a pivotal role in the health of their hosts. Music and noise are prevalent environmental factors in human society and animal production and are reported to impact their welfare and physiological conditions; however, the information on the relationship between the microbiota, physiological status, and sound is limited. This study investigated the impact of music and white noise exposure in mice through 16s rRNA gene sequencing, enzyme assay, and qPCR. The results demonstrate that white noise induced oxidative stress in animals by decreasing serum SOD and GSH-PX activity while increasing LDH activity and MDA levels (p < 0.05). Conversely, no oxidative stress was observed in the music treatment group. The relative gene expression of IFN-γ and IL-1ß decreased in the white noise group compared to the music and control groups. The 16s rRNA gene amplicon sequencing revealed that Bacteroidetes, Firmicutes, Verrucomicrobia, and Proteobacteria were dominant among all the groups. Furthermore, the proportion of Firmicutes increased in the music treatment group but decreased in the white noise treatment group compared to the control group. In conclusion, white noise has detrimental impacts on the gut microbiota, antioxidant activity, and immunity of mice, while music is potentially beneficial.

The addition of nano zero-valent iron during compost maturation effectively removes intracellular and extracellular antibiotic resistance genes by reducing the abundance of potential host bacteria.

Applying compost to soil may lead to the spread of antibiotic resistance genes (ARGs) in the environment. Therefore, removing ARGs from compost is critical. In this study, for the first time, nano zero-valent iron (nZVI) was added to compost during the maturation stage to remove ARGs. After adding 1 g/kg of nZVI, the abundance of total intracellular and total extracellular ARGs was decreased by 97.62% and 99.60%, and that of total intracellular and total extracellular mobile genetic elements (MGEs) was decreased by 92.39% and 99.31%, respectively. A Mantel test and network analysis indicated that the reduction in potential host bacteria and intI1 after nZVI treatment promoted the removal of intracellular and extracellular ARGs. The addition of nZVI during composting reduced the horizontal transfer of ARGs and improve the total nitrogen and germination index of compost, allowing it to meet the requirements for organic fertilizers.

The tigecycline resistance gene tetX has an expensive fitness cost based on increased outer membrane permeability and metabolic burden in Escherichia coli.

Livestock-derived tetX-positive Escherichia coli with tigecycline resistance poses a serious risk to public health. Fitness costs, antibiotic residues, and other tetracycline resistance genes (TRGs) are fundamental in determining the spread of tetX in the environment, but there is a lack of relevant studies. The results of this study showed that both tetO and tetX resulted in reduction in growth and an increased in the metabolic burden of E. coli, but the presence of doxycycline reversed this phenomenon. Moreover, the protection of E. coli growth and metabolism by tetO was superior to that of tetX in the presence of doxycycline, resulting in a much lower competitiveness of tetX-carrying E. coli than tetO-carrying E. coli. The results of RNA-seq showed that the increase in outer membrane proteins (ompC, ompF and ompT) of tetX-carrying E. coli resulted in increased membrane permeability and biofilm formation, which is an important reason for fitness costs. Overall, the increased membrane permeability and metabolic burden of E. coli is the mechanistic basis for the high fitness cost of tetX, and the spread of tetO may limit the spread of tetX. This study provides new insights into the rational use of tetracycline antibiotics to control the spread of tetX.

Design and Modeling of a Microfluidic Coral Polyps Culture Chip with Concentration and Temperature Gradients.

Traditional methods of cultivating polyps are costly and time-consuming. Microfluidic chip technology makes it possible to study coral polyps at the single-cell level, but most chips can only be analyzed for a single environmental variable. In this work, we addressed these issues by designing a microfluidic coral polyp culture chip with a multi-physical field for multivariable analyses and verifying the feasibility of the chip through numerical simulation. This chip used multiple serpentine structures to generate the concentration gradient and used a circuit to form the Joule effect for the temperature gradient. It could generate different temperature gradients at different voltages for studying the growth of polyps in different solutes or at different temperatures. The simulation of flow field and temperature showed that the solute and heat could be transferred evenly and efficiently in the chambers, and that the temperature of the chamber remained unchanged after 24 h of continuous heating. The thermal expansion of the microfluidic chip was low at the optimal culture temperature of coral polyps, which proves the feasibility of the use of the multivariable microfluidic model for polyp culture and provides a theoretical basis for the actual chip processing.

Dopant-site lattice turbulence of Cu-substituted Nb2O5 for efficient nitrogen electroreduction.

Lattice disorder engineering on highly crystalline texture toward high-efficiency N2-to-NH3 electrocatalysis is tremendously challenging. Here, abundant lattice disturbances were established on an ultrafine Nb2O5 nanoparticle by Cu substitution. Cu-Nb2O5 anchored on a carbon material (Cu-Nb2O5@C) exhibits excellent activity and high selectivity for N2 electroreduction to NH3 with a yield rate of 28.07 µg h-1 mg-1 and a faradaic efficiency (FE) of 13.25% at -0.2 V vs. reversible hydrogen electrode (RHE) in acidic electrolyte. Cu-Nb2O5@C presents superb durability with no obvious change in catalyst constituents and structure after N2 reduction as confirmed by ex situ characterization studies. The excellent catalytical performance should originate from structural superiority of lattice turbulence for more active sites and optimized electronic state as well as good conductivity of carbon support. Meanwhile, in neutral electrolyte, the NH3 FE also reaches up to 10.29% at the same potential.

Modified cornstalk biochar can reduce ammonia emissions from compost by increasing the number of ammonia-oxidizing bacteria and decreasing urease activity.

This study examined how the addition of modified cornstalk biochar (CB) affected ammonia (NH3) emissions during composting. Four treatments were established, including a control (CK) with layer manure and sawdust only, and the CK mixtures adding 10% HNO3 CB (NA), 10% H2O2 CB (HP) and 10% HNO3- H2O2 CB (MI). As the results showed, NH3 emissions was reduced by 47.83% (NA), 61.69% (HP) and 45.69% (MI) when the modified CB used as a compost additive (P < 0.05). According to the data analysis, the addition of modified CB significantly increased the number of ammonia-oxidizing bacteria (AOB), inhibited urease activity and decreased the abundance of narG and nirS at rising temperatures and high temperatures (P < 0.05). Redundancy analysis demonstrated a negative correlation between NH3 emissions and AOB and a positive correlation with urease activity, narG and nirS. Thus, the modified CB helped reduce NH3 emissions by regulating nitrification processes.

Animal manures application increases the abundances of antibiotic resistance genes in soil-lettuce system associated with shared bacterial distributions.

An increasing amount of animal manures is being used in agriculture, and the effect of animal manures application on the abundance of antibiotics resistance genes (ARGs) in soil-plant system has attracted widespread attention. However, the impacts of animal manures application on the various types of bacterial distribution that occur in soil-lettuce system are unclear. To address this topic, the effects of poultry manure, swine manure or chemical fertilizer application on ARG abundance and the distribution of shared bacteria were investigated in this study. In a lettuce pot experiment, 13 ARGs and 2 MGEs were quantified by qPCR, and bacterial communities in the soil, lettuce endosphere and lettuce phyllosphere were analysed by 16S rRNA sequence analysis. The results showed that the application of poultry or swine manure significantly increased ARG abundance in the soil, a result attributed mainly to increases in the abundances of tetG and tetC. The application of poultry manure, swine manure and chemical fertilizer significantly increased ARG abundance in the lettuce endosphere, and tetG abundance was significantly increased in the poultry and swine manure groups. However, animal manures application did not significantly increase ARG abundance in the lettuce phyllosphere. Flavobacteriaceae, Sphingomonadaceae and 11 other bacterial families were the shared bacteria in the soil, lettuce endosphere, and phyllosphere. The Streptomycetaceae and Methylobacteriaceae were significantly positively correlated with intI1 in both the soil and endosphere. Chemical fertilizer application increased both the proportions of Sphingomonadaceae and tetX abundance, which were positively correlated in the endosphere. Comamonadaceae and Flavobacteriaceae were not detected in the lettuce endosphere under swine manure application. Cu was related to Flavobacteriaceae in the lettuce endosphere. Overall, poultry and swine manure application significantly increased ARG abundance in the soil-lettuce system, which might be due to the shared bacterial distribution.