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Expression and purification of β-galactosidases derived from Bifidobacterium provide a new resource for efficient lactose hydrolysis and lactose intolerance alleviation. Here, we cloned and expressed two β-galactosidases derived from Bifidobacterium. The optimal pH for BLGLB1 was 5.5, and the optimal temperature was 45 °C, at which the enzyme activity of BLGLB1 was higher than that of commercial enzyme E (300 ± 3.6 U/mg) under its optimal conditions, reaching 2200 ± 15 U/mg. The optimal pH and temperature for BPGLB1 were 6.0 and 45 °C, respectively, and the enzyme activity (0.58 ± 0.03 U/mg) under optimum conditions was significantly lower than that of BLGLB1. The structures of the two β-galactosidase were similar, with all known key sites conserved. When o-nitrophenyl-β-D-galactoside (oNPG) was used as an enzyme reaction substrate, the maximum reaction velocity (Vmax) for BLGLB1 and BPGLB1 was 3700 ± 100 U/mg and 1.1 ± 0.1 U/mg, respectively. The kinetic constant (Km) of BLGLB1 and BPGLB1 was 1.9 ± 0.1 and 1.3 ± 0.3 mmol/L, respectively. The respective catalytic constant (kcat) of BLGLB1 and BPGLB1 was 1700 ± 40 s−1 and 0.5 ± 0.02 s−1, respectively; the respective kcat/Km value of BLGLB1 and BPGLB1 was 870 L/(mmol∙s) and 0.36 L/(mmol∙s), respectively. The Km, kcat and Vmax values of BLGLB1 were superior to those of earlier reported β-galactosidase derived from Bifidobacterium. Overall, BLGLB1 has potential application in the food industry. [ABSTRACT FROM AUTHOR]

Optical and microwave communication classically focus more on the magnitude manipulation of electromagnetic carriers. Recently, a multiplexing method utilizing orbital angular momentum (OAM) is developed, which has been an important study of communication art. Based on OAM multiplexing, a communication method that introduces Berry‐phase carriers is presented in this research, which can naturally eliminate the channel disturbance. To verify the proposed method, two information systems are presented, including a multiplexing communication system in a large‐scale scenario and a double‐helical information system in a microscale scenario. All the results are verified by the corresponding experiments. This method achieves some advanced performances, for instance, directional communication and self‐anti‐interference, which shows potential applications in areas such as information, materials, and bionics. [ABSTRACT FROM AUTHOR]

Microbe-driven ammonia nitrogen removal plays a crucial role in the nitrogen cycle and wastewater treatment. However, the rational methods and mechanisms for boosting nitrogen conversion through microbial domestication are still limited. Herein, a combined alkali-photocatalytic stimulation strategy was developed to activate the Halomonas shizuishanensis DWK9 for efficient ammonia nitrogen removal. The strain DWK9 selected from saline-alkaline soil in Northwestern China possessed strong resistance to stress of saline-alkaline environment and free radicals, and was abundant in nitrogen conversion genes, thus is an ideal model for advanced microbial domestication. Bacterial in the combined alkali-photocatalytic stimulation group achieved a high ammonia nitrogen conversion rate of 67.5 %, 10 times outperforming the non-stimulated and single alkali/photocatalytic stimulation control groups. Morphology analysis revealed that the bacteria in the alkali-photocatalytic stimulated group formed a favorable structure for bioelectric transfer. Remarkably, the domesticated bacteria demonstrated improved electrochemical properties, including increased current capacity and lower overpotentials and impedance. Prokaryotic transcription genetic analysis together with qPCR analysis showed upregulation of denitrification-related metabolic pathway genes. A novel FAD dependent and NAD(P)H independent energy mode has been proposed. The universality and effectiveness of the as-developed combined alkali-photocatalytic microbial domestication strategy were further validated through indicator fish survival experiments. This work provides unprecedented degrees of freedom for the exploration of rational microbial engineering for optimized and controllable biogeochemical conversion. [Display omitted] • A combined alkali-photocatalytic (CAP) promotion strategy was developed to activate bacteria. • Improved electrochemical properties in DWK9 bacteria suggest effective electron migration. • Favorable denitrification-related metabolic pathway genes change were verified. • The 2-electrons pathway dominated by FAD is the core promotion mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spontaneous polarization enhances carrier separation. • The energy efficiency of pyroelectric photocatalysis may exceed 10%. • Cognitive gap in situ characterization of pyroelectric photocatalysts is reviewed. • Proposed directions for future large-scale pyroelectric photocatalysis. Photocatalysis, in which semiconductors are used to harvest light and produce charge carrier derivatives, has been widely valued as a promising sustainable technique. However, due to the poor separation efficiency of photogenerated electron-hole pairs, the overall energy conversion efficiency sticks at 1%, which is far from the desired industrial application demand of 10%. Very recently, pyroelectric catalysis technology with asymmetric positive/negative charge centers has emerged, which is hoped to play a key role in alleviating energy crisis and environmental problems. With pyroelectric catalysts introduced into photocatalysts, its internal spontaneous polarization electric field can effectively promote the separation of photogenerated carriers, thus improving the photocatalytic performance. Therefore, pyroelectric photocatalysis is expected to break the widely recognized energy efficiency threshold of 10% for scale-up industrial implementation of photocatalytic technique. Nevertheless, there is still a huge cognitive gap between fundamental theory and practice in the design, characterizations, and application of pyroelectric photocatalysts. Hence, a comprehensive review is conducted to understand the state-of-the-art progress in pyroelectric photocatalysis. The polarization treatment, evaluation parameters and the corresponding atomic force microscopy and X-ray diffraction characterization for the identification of high-efficiency pyroelectric materials are also elaborated. We also propose five potential directions for large-scale applications of pyroelectric photocatalysis, including multi-step cascade reactions, controllable reactions, excitable biomaterials, hazardous waste treatment, and water wave energy collection devices. [ABSTRACT FROM AUTHOR]

The extracellular secreted protein of Bifidobacterium longum (B. longum) plays an important role in maintaining the homeostasis of the human intestinal microenvironment. However, the mechanism(s) of interaction remain unclear. Lysozyme is a kind of antibacterial peptide. In this study, the amino acid sequence of a lysozyme-like protein of B. longum based on whole-genome data of an isolate from human gut feces was found. We further predicted functional domains from the amino acid sequence, purified the protein, and verified its bioactivity. The growth of some bacteria were significantly delayed by the 020402_LYZ M1 protein. In addition, the gut microbiota was analyzed via high-throughput sequencing of 16S rRNA genes and an in vitro fermentation model, and the fluctuations in the gut microbiota under the treatment of 020402_LYZ M1 protein were characterized. The 020402_LYZ M1 protein affected the composition of human gut microbiota significantly, implying that the protein is able to communicate with intestinal microbes as a regulatory factor. [ABSTRACT FROM AUTHOR]

The vacant house is an essential phenomenon of urban decay and population loss. Exploration of the correlations between housing vacancy and some socio-environmental factors is conducive to understanding the mechanism of urban shrinking and revitalization. In recent years, rapidly developing night-time remote sensing, which has the ability to detect artificial lights, has been widely applied in applications associated with human activities. Current night-time remote sensing studies on housing vacancy rates are limited by the coarse spatial resolution of data. The launch of the Jilin1-03 satellite, which carried a high spatial resolution (HSR) night-time imaging camera, provides a new supportive data source. In this paper, we examined this new high spatial resolution night-time light dataset in housing vacancy rate estimation. Specifically, a stepwise multivariable linear regression model was engaged to estimate the housing vacancy rate at a very fine scale, the census tract level. Three types of variables derived from geospatial data and night-time image represent the physical environment, landuse (LU) structure, and human activities, respectively. The linear regression models were constructed and analyzed. The analysis results show that (1) the HVRs estimating model using the Jilin1-03 satellite and other ancillary geospatial data fits well with the Census statistical data (adjusted R2 = 0.656, predicted R2 = 0.603, RMSE = 0.046) and thus is a valid estimation model; (2) the Jilin1-03 satellite night-time data contributed a 28% (from 0.510 to 0.656) fitting accuracy increase and a 68% (from 0.359 to 0.603) predicting accuracy increase in the estimate model of the housing vacancy rate. Reflecting socio-economic conditions, the luminous intensity of commercial areas derived from the Jilin1-03 satellite is the most influential variable to housing vacancy. Land use structure indirectly and partially demonstrated that the social environment factors in the community have strong correlations with residential vacancy. Moreover, the physical environment factor, which depicts vegetation conditions in the residential areas, is also a significant indicator of housing vacancy. In conclusion, the emergence of HSR night light data opens a new door to future microscopic scale study within cities. [ABSTRACT FROM AUTHOR]

Because of the connection constraints of quantum devices, the quantum gate cannot operate directly on nonadjacent qubits. Quantum circuit mapping transforms a logical quantum circuit to a circuit that satisfies the connection constraints by adding SWAP gates for nonadjacent qubits. Global and local heuristic reordering strategies are proposed in this paper for quantum circuit mapping over linear nearest neighbor (LNN) architectures, which are one-dimensional topology structures, to reduce the number of SWAP gates added. Experiment results show that the average improvements of the two methods are 13.19% and 15.46%, respectively. In this paper, we consider the quantum circuit mapping problem for linear nearest neighbor (LNN) architectures. We propose a global heuristic qubit reordering optimization algorithm and a local heuristic qubit reordering optimization algorithm. Compared with the other algorithm results, the average improvements of the two methods for quantum cost are 13.19% and 15.46%, respectively. The two methods apply to the realization of quantum circuit neighboring over one-dimensional quantum architectures and can be extended to algorithms that work for other quantum architectures of different topologies. [ABSTRACT FROM AUTHOR]

We report on the observation of the electromagnetic focusing effect of zero orbital angular momentum (OAM) after introducing the multi-grade OAM concept. It performs the same feature in the central area around the focal point, while the typical Airy disk is transformed into a vortical cloud pattern beside the central area. Quantized focusing phenomena are exhibited based on the periodicity of the OAM. These results were verified by simulation and experiments. Our method achieves an optical focusing theory through OAM manipulation, which can be applied in imaging, photoetching, and communication. Furthermore, it also provides an opportunity for energy harvesting from natural OAM materials. [ABSTRACT FROM AUTHOR]

In this study, the potential climate change impacts on rice growth and rice yield under 1.5 and 2.0 °C warming scenarios, respectively, are simulated using the Ceres-Rice Model based on high-quality, agricultural, experimental, meteorological and soil data, and the incorporation of future climate data generated by four Global Climate Models (GCMs) in the Pearl River Delta, China. The climatic data is extracted from four Global Climate Models (GCMs) namely: The Community Atmosphere Model 4 (CAM4), The European Centre for Medium-Range Weather Forecasts-Hamburg 6 (ECHAM6), Model for Interdisciplinary Research On Climate 5 (MIROC5) and the Norwegian Earth System Model 1 (NorESM1). The modeling results show that climate change has major negative impacts on both rice growth and rice yields at all study sites. More specifically, the average of flowering durations decreases by 2.8 days (3.9 days), and the maturity date decreases by 11.0 days (14.7 days) under the 1.5 °C and (2.0 °C) warming scenarios, respectively. The yield for early mature rice and late mature rice are reduced by 292.5 kg/ha (558.9 kg/ha) and 151.8 kg/ha (380.0 kg/ha) under the 1.5 °C (2.0 °C) warming scenarios, respectively. Adjusting the planting dates of eight days later and 15 days earlier for early mature rice and late mature rice are simulated to be adaptively effective, respectively. The simulated optimum fertilizer amount is about 240 kg/ha, with different industrial fertilizer and organic matter being applied. [ABSTRACT FROM AUTHOR]

Many studies have obtained high-quality plant point clouds but it remains difficult to extract the midrib from a leaf point cloud. In this study, a fast and accurate approach to the extraction of leaf midrib from point clouds was developed. The leaf was converted into its principal component analysis (PCA) coordinates to find the tip and base points of the leaf. A new search algorithm was proposed, which quickly searched for the approximate shortest curve between tip and base points on the leaf point cloud. The curve then was projected and fitted to eliminate the deviation between the curve and the leaf midrib. Two types of point cloud, generated using the structure-from-motion method and using a laser scanner, were obtained to verify our approach. As a result, the extracted curves were both in good agreement with the leaf midrib for the two kinds of point clouds. Compared with manual measurements of the leaf length, the root-mean-square error (RMSE) of the lengths of the two types of the extracted curve were 2.55 mm and 1.38 mm, respectively. The result shows that our method is robust and practical and may assist in the development of plant morphology measurements. [ABSTRACT FROM AUTHOR]

(A) Resistant starch RS3 administered in combination with Lactiplantibacillus plantarum strain 84-3 by human gut microbiota in simulated fermentation experiments in vitro and in a rat model. (B) Schematic diagram of granular RS3 in combination with Lactiplantibacillus plantarum strain 84-3 fermentation. [Display omitted] • Lactiplantibacillus plantarum strain 84-3 (Lp84-3) degrades resistant starch (RS3). • Lp84-3 promoted the microbial production of SCFAs from RS3 in vitro. • Lp84-3 promoted Lactobacillus and Akkermansia growth in the presence of RS3 in vitro. • Lp84-3 and RS3 administration promoted faecal SCFA levels in a rat model. • Lp84-3 and RS3 administration enhanced faecal microbial metabolism in vivo. This study aimed to investigate the metabolic and population responses of gut microbiota to resistant starch (RS3) in the presence of exogenous Lactiplantibacillus plantarum strain 84-3 (Lp84-3) in vitro and in vivo. Lp84-3 promoted acetate, propionate, and butyrate production from RS3 by gut microbiota and increased Lactobacillus and Blautia contents in vitro. Furthermore, in the presence of Lp84-3, starch granules presented a "dot-by-hole" fermentation pattern. Administration of Lp84-3 with RS3 increased the level of SCFA-producing Faecalibaculum , Parabacteroides , Alistipes , and Anaeroplasma in the faeces of rates, with Lactobacillus and Akkermansia representing the key genera that significantly promoted SCFAs, especially propionate and butyrate. Lp84-3 with RS3 promoted genes related to tryptophan synthase (EC 4.2.1.20) and beta-glucosidase (EC 3.2.1.21) in faecal bacteria. Our findings highlight the ability of Lp84-3 to enhance RS3 degradation, possibly by promoting SCFA-producing bacteria, and indicate that Lp84-3 could be a potential probiotic with a beneficial effect on gut microbiota. [ABSTRACT FROM AUTHOR]

• Cycloastragenol (CAG) prevents age-related bone loss in aging rat models. • CAG inhibits bone resorption and improves bone formation. • Anti-osteoporosis effects of CAG may be due to upregulation of osteoactivin expression Aging-induced bone loss is a multifactorial, age-related, and progressive phenomenon among the general population and may further progress to osteoporosis and increase the risk of fractures. Cycloastragenol (CAG), currently the only compound reported that activates human telomerase, is thought to be able to alleviate or delay the symptoms of aging and chronic diseases. Previous research has suggested that CAG may have the potential to alleviate age-related bone loss. However, to date, no research has specifically focused on this aspect. In this study, we aimed to investigate whether CAG could prevent senile osteoporosis, and further reveal its underlying mechanism. CAG treatment was administrated into two bone loss rat models (D-galactose administration and aging) for 20 weeks and 33 weeks, respectively. Serum biomarkers analyses, bone biomechanical tests, micro-computed tomography assessment, and bone histomorphometry analyses were performed on the bone samples collected at the endpoint, to determine whether CAG could prevent or alleviate age-related bone loss. Proteomic analysis was performed to reveal the changes in protein profiles of the bones, and western blot was used to further verify the identity of the key proteins. The viability, osteoblastic differentiation, and mineralization of MC3T3-E1 cells were also evaluated after CAG treatment in vitro. The results suggest that CAG treatment improves bone formation, reduces osteoclast number, alleviates the degradation of bone microstructure, and enhances bone biomechanical properties in both d -galactose- and aging-induced bone loss models. CAG treatment promotes viability, osteoblastic differentiation, and mineralization in MC3T3-E1 cells. Proteomic and western blot analyses revealed that CAG treatment increases osteoactivin (OA) expression to alleviate bone loss. The results revealed that CAG alleviates age-related bone loss and improves bone microstructure and biomechanical properties. This may due to CAG-induced increase in OA expression. In addition, the results support preclinical investigations of CAG as a potential therapeutic medicine for the treatment of senile osteoporosis. [ABSTRACT FROM AUTHOR]

Herein, we propose an approach for sensitivity improvement of dual-axis strain sensing using the property of a metasurface (MS) that the phase response shifts sharply with the MS deformation. A feasible approach for phase measurement is first demonstrated by calculating multi-polarized reception when the incident electromagnetic (EM) wave has anisotropic phase values. A flexible MS consisting of periodically arranged lantern-shaped elements is designed and fabricated for dual-axis strain sensing and evaluation based on the proposed method. The simulation and measurement results demonstrated a high sensitivity of the proposed MS for strain sensing in the microwave band. The method can be used potentially in both pressure and tensile sensing. Moreover, the operational frequency can be extended to the THz range and even to the optical band. [ABSTRACT FROM AUTHOR]