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Summary: Glycine‐rich RNA‐binding proteins (GRPs) have been implicated in the responses of plants to environmental stresses, but the function of GRP genes involved in salt stress and the underlying mechanism remain unclear. In this study, we identified BpGRP1 (glycine‐rich RNA‐binding protein), a Betula platyphylla gene that is induced under salt stress. The physiological and molecular responses to salt tolerance were investigated in both BpGRP1‐overexpressing and suppressed conditions. BpGRF3 (growth‐regulating factor 3) was identified as a regulatory factor upstream of BpGRP1. We demonstrated that overexpression of BpGRF3 significantly increased the salt tolerance of birch, whereas the grf3‐1 mutant exhibited the opposite effect. Further analysis revealed that BpGRF3 and its interaction partner, BpSHMT, function upstream of BpGRP1. We demonstrated that BpmiR396c, as an upstream regulator of BpGRF3, could negatively regulate salt tolerance in birch. Furthermore, we uncovered evidence showing that the BpmiR396c/BpGRF3 regulatory module functions in mediating the salt response by regulating the associated physiological pathways. Our results indicate that BpmiR396c regulates the expression of BpGRF3, which plays a role in salt tolerance by targeting BpGRP1. [ABSTRACT FROM AUTHOR]

Given the difficulties in measuring the effective wind speed of wind turbine during the maximum power point tracking (MPPT) process and the unknown nature of the system, this paper proposes a neural network super-twisted sliding mode control (NNST-SMC) method with echo state network (ESN) wind speed estimation. The rotor speed and electromagnetic power are taken as ESN inputs, and the effective wind speed is estimated through the inverse model of wind turbine dynamics. The super-twisted algorithm (STA) can effectively improve the chattering problem of the traditional sliding mode control (SMC) system. The RBF neural network is introduced to compensate for disturbance and uncertainty characteristics of the wind turbine. Results show that compared with the neural network first-order sliding mode control (NNSMC) and super-twisted sliding mode control (ST-SMC), the proposed method can improve the efficiency of wind energy utilization. [ABSTRACT FROM AUTHOR]

Detection of small biomolecules is critical for understanding molecular mechanisms in biological systems and performing in vitro diagnosis in clinics. Current antibody based detection methods face large challenges in detecting small biomolecules at low concentrations. We report a new method for detecting small biomolecules based on molecular recognition and nanoparticle (NP) counting. Aptamer-functionalized NPs are attached to complementary sequence (CS)-conjugated microparticle (MP) carriers. In the presence of target small biomolecules at ultra low concentrations, NPs would be released from the MP carriers. Coupled with a resistive pulse sensor (RPS) using a micropore that counts the released NPs, this method can measure the concentrations of target biomolecules at low concentrations with high sensitivity and high throughput. Adenosine was used as a model to demonstrate the feasibility of this method. It is demonstrated that this method can detect a wide range of adenosine concentrations with a low detection limit of 0.168 nM, which is 10 times lower than that of the ELISA kit. With its simple structure, high sensitivity, and high reproducibility, this detection method holds great potential for the ultrasensitive detection of low abundance small biomolecules. • Nanoparticles are released from a carrier in the presence of target analytes. • The released nanoparticles can be detected in response to a wide range of analyte concentration. • Ultrasensitive detection of biomolecules can be achieved via molecular recognition coupled with nanoparticle counting. [ABSTRACT FROM AUTHOR]

Many cellular functions are regulated by cell surface charges, such as intercellular signaling and metabolism. Noninvasive measurement of surface charge distribution of a single cell plays a vital role in understanding cellular functions via cell membranes. We report a method for cell surface charge mapping via photoelectric interactions. A cell is placed on an array of microelectrodes fabricated on a transparent ITO (indium tin oxide) surface. An incident light irradiates the ITO surface from the backside. Because of the influence of the cell surface charge (or zeta potential), the photocurrent and the absorption of the incident light are changed, inducing a magnitude change of the reflected light. Hence, the cell surface charge distribution can be quantified by analyzing the reflected light intensity. This method does not need physical or chemical modification of the cell surface. We validated this method using charged microparticles (MPs) and two types of cells, i.e., human dermal fibroblast cells (HDFs) and human mesenchymal stem cells (hMSC). The measured average zeta potentials were in good agreement with the standard electrophoresis light scattering method. [ABSTRACT FROM AUTHOR]

Soil microbiota are significantly influenced by their microenvironments. Therefore, to understand the impacts of various land use patterns on the diversity and composition of soil bacterial communities, this study focused on three typical land use types—NF (natural forest), AF (artificial forests), and FL (farmland)—in the Heilongjiang Central Station Black-billed Capercaillie National Nature Reserve, located in the southwestern part of Heihe City, Heilongjiang Province, China. Using high-throughput sequencing of the 16S rRNA gene, we examined the soil bacterial community structures in these different land use types and explored their correlation with soil environmental factors. The following were our main observations: (1) Significant variations in soil chemical properties among different land use patterns were observed. In artificial forests, total nitrogen (TN), alkali hydrolyzed nitrogen (AN), total phosphorus (TP), and available phosphorus (AP) were higher compared to farmland and significantly higher than those in natural forests. Furthermore, the organic carbon content (SOC) in natural forests was higher than in artificial forests and significantly higher than in farmland. (2) Comparative analysis using the Shannon and Simpson indices revealed that bacterial community diversity was higher in artificial forests than in natural forests, which was significantly higher than in farmland. (3) The effect of different land use types on soil bacterial community structure was not significant. The three land types were dominated by Proteobacteria, Acidobacteria, and Actinobacteria. Proteobacteria exhibited a higher relative abundance in farmland and artificial forests compared to natural forests, whereas Actinobacteria exhibited the lowest relative abundance in natural forests. (4) Redundancy analysis (RDA) revealed that SOC, TN, AN, and AP were key environmental factors influencing the microbial communities of soil. Collectively, our findings demonstrated that land use practices can significantly alter soil nutrient levels, thereby influencing the structure of bacterial communities. [ABSTRACT FROM AUTHOR]

Simple Summary: Although wheat is primarily planted to harvest wheat grain, whole crop wheat hay (WCWH) could also be an efficient ruminant feeding source. While the nutrient content and digestibility of WCWH greatly depends on the maturity stage, the optimal harvest stage for making WCWH has been hardly studied. In this study, we evaluated the nutrient content and in vitro digestibility of WCWH harvested during the flowering, late milk and dough stages. Though the neutral detergent fiber content was lower and the starch to non-fibrous carbohydrate (NFC) ratio was greater in the dough stage, we determined that the optimal harvest stage should be the late milk stage due to the greater dry matter digestibility, the relatively greater NFC content and the shorter planting days. The nutritional value of whole crop wheat hay (WCWH) harvested at different maturation stages are different, and its feeding effects on dairy cows have not been thoroughly evaluated. In this study, the in vitro digestibility of whole wheat (Nongda 22) hay harvested during the flowering, late milk and dough stages were evaluated using batch culture technique. The neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of whole wheat hay decreased by 35.5% and 40.4%, respectively, whereas the non-fibrous carbohydrates (NFC) content increased by 50.3% in WCWH harvested during the dough stage as compared to the flowering stage (p < 0.01). The pH of the fermentation liquid and acetate to propionate ratio was greatest in the wheat harvested during the flowering stage and lowest during the dough stage (p = 0.03), whereas the volatile fatty acid (VFA) concentration was greatest during the dough stage and lowest during the flowering stage (p < 0.01). The dry matter loss (DML) was 9.6% and 6.2% greater (p < 0.01) during the late milk stage than in the flowering or dough stages, and the NDF loss (NDFL; p = 0.01) and ADF loss (ADFL; p < 0.01) was greater in both the flowering and late milk stages. In conclusion, though the content of NDF was lower in the dough stage, and the starch to NFC ratio was greater, we determined that the optimal harvest stage should be the late milk stage due to the greater dry matter digestibility, the relatively greater NFC content and the shorter planting days. [ABSTRACT FROM AUTHOR]

Many bio-functions of cells can be regulated by their surface charge characteristics. Mapping surface charge density in a single cell's surface is vital to advance the understanding of cell behaviors. This article demonstrates a method of cell surface charge mapping via electrostatic cell–nanoparticle (NP) interactions. Fluorescent nanoparticles (NPs) were used as the marker to investigate single cells' surface charge distribution. The nanoparticles with opposite charges were electrostatically bonded to the cell surface; a stack of fluorescence distribution on a cell's surface at a series of vertical distances was imaged and analyzed. By establishing a relationship between fluorescent light intensity and number of nanoparticles, cells' surface charge distribution was quantified from the fluorescence distribution. Two types of cells, human umbilical vein endothelial cells (HUVECs) and HeLa cells, were tested. From the measured surface charge density of a group of single cells, the average zeta potentials of the two types of cells were obtained, which are in good agreement with the standard electrophoretic light scattering measurement. This method can be used for rapid surface charge mapping of single particles or cells, and can advance cell-surface-charge characterization applications in many biomedical fields. [ABSTRACT FROM AUTHOR]

Background and Objective: Radiofrequency ablation (RFA) is a safe and less invasive technique that uses an electric current to damage nerve tissue to stop it from sending pain signals. This study was aimed to determine the molecular mechanism of neuropathologic damage induced by RFA at different temperatures. Methods: A total of 36 Sprague Dawley rats were used as model with neuropathological injury. These rats were divided into six groups based on the temperature stimulation at 42°C, 47°C, 52°C, 57°C, 62°C, and 67°C. Conduction time, distance, and velocity were recorded after thermal injury. Hematoxylin and eosin staining was used to observe the histopathological changes of sciatic nerve. Neural ion channel proteins such as sodium voltage-gated channel alpha subunit 9 (SCN9A), sodium channel B3 subunit (SCN3B) and neurofascin (NFASC) expression in sciatic nerve tissue were detected detected by Western Blot. Results: Nerve conduction velocity (NCV) gradually decreased with the increase in temperature and neuronal damage was seen at 67°C. HandE staining showed increased degeneration of neurons with an increase in temperature from 47°C to 67°C. SCN9A and SCN3B expression at 57°C, 62°C, and 67°C was much higher; however, NFASC expression was lower at same temperatures. Conclusion: Neuropathological damage caused by RFA at different temperatures shows positive correlation with NCV. Heat transfer injury affects the expression of SCN9A, SCN3B, and NFASC in sciatic nerve tissue. [ABSTRACT FROM AUTHOR]

• N-carbamylglutamate (NCG) improved the production performance of dairy cows. • NCG enhanced antioxidant capacity and immune function to ameliorate heat stress. • NCG reduced blood urea nitrogen and ammonia, while increased serum glucose. • Sixteen plasma metabolites related to heat stress were improved by NCG. • Pathway analysis revealed the potential mechanism of NCG on heat stress. Heat stress is a serious threat to dairy cow health worldwide. N-carbamylglutamate (NCG), a novel feed additive, has been applied in dairy cow industry. However, the effects and mechanisms of NCG on dairy cows under heat stress are still unknown. A total of 48 Holstein dairy cows with similar days in milk (154 ± 13.6 d), parity (1-3), and body condition score were randomly divided into 4 groups of 12 animals each. Under heat stress, the cows were fed a TMR diet supplemented with 0 (control), 15, 20, 25 g of NCG/d per cow for 60 days. Milk production performance was recorded and serum parameters were examined. Meanwhile, metabolomics study of plasma based on liquid chromatography-mass spectrometry was also applied to investigate metabolites and pathways in response to NCG supplementation. Milk yield was increased but milk urea nitrogen was reduced by the NCG treatment. Addition of 15 g of NCG/d increased the milk protein percentage compared with the control. No effect of NCG was observed on dry matter intake, lactose percentage, milk fat percentage and somatic cell count. Serum glucose concentrations in cows fed with 15, 20, 25 g of NCG/d were 5.34 ± 0.312, 5.78 ± 0.473 and 5.54 ± 0.711 mmol/L, which were greater than those in the control (4.87 ± 0.367 mmol/L, P < 0.05). Meanwhile, the concentrations of blood urea nitrogen and blood ammonia were decreased with the addition of NCG. Results for antioxidant capacity and immune function showed beneficial effects of NCG, such as the increases in total antioxidant capacity, superoxide dismutase, glutathione peroxidase, IgG, IgM and IgA. Clear separations of plasma metabolic profiles between control and NCG groups were observed in the score plots. Sixteen different metabolites involved in metabolisms of amino acids, ketone bodies, butanoate and energy, as well as gut microbiome-derived metabolism were regulated by NCG supplementation. In conclusion, supplementation with NCG has the potential to enhance production performance, antioxidant capacity and immune function, and improved the metabolic profile of dairy cows under heat stress. [ABSTRACT FROM AUTHOR]