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Cobalt oxides are known for their excellent heat transfer properties. The main component of cobalt oxides is the CoO2 monolayer, which exhibits high-temperature superconductivity caused by strong electron–phonon coupling (EPC). We here systematically investigate the structural stability, electronic structure, and magnetism of the CoO2 monolayer using first-principles and Monte Carlo simulations. On this basis, we further study the changes in the spin energy gap, magnetic axis direction, and other properties of the CoO2 monolayer with the changes in carrier concentration. By appropriately doping the CoO2 monolayer with holes, the magnetic axis direction of the CoO2 monolayer can be reversed, thereby enhancing its potential application in the field of spin electronic devices. Monte Carlo simulation is used to study the regulation of different factors on the magnetothermal properties of the CoO2 monolayer. Through the analysis of physical parameters such as Curie temperature (TC) and bandgap, we find that the appropriate carrier concentration and magnetic field can not only regulate the magnetothermal properties of materials but also further improve the efficiency of materials in low-temperature environments. [ABSTRACT FROM AUTHOR]

Abstract Alkenylboronates are highly versatile building blocks and valuable reagents in the synthesis of complex molecules. Compared with that of monosubstituted alkenylboronates, the synthesis of multisubstituted alkenylboronates is challenging. The copper‐catalyzed carboboration of alkynes is an operationally simple and straightforward method for synthesizing bis/trisubstituted alkenylboronates. In this work, a series of copper‐metallized N‐Heterocyclic Carbene (NHC) ligand porous polymer catalysts are designed and synthesized in accordance with the mechanism of carboboration. By using CuCl@POL‐NHC‐Ph as the optimal nanocatalyst, this study realizes the β‐regio‐ and stereoselective (syn‐addition) 1,2‐carboboration of alkynes (regioselectivity up to >99:1) with satisfactory yields and a wide range of substrates. This work not only overcomes the selectivity of carboboration but also provides a new strategy for the design of nanocatalysts and their application in organic synthesis.

The degradation of water quality and decline in purification capacity of lakeshore zones due to anthropogenic activities and climate change is a growing concern in China. The identification of the critical width of the lakeshore zone remains a challenge due to natural geographic features and pollutant types, that is why a general identification approach has yet to be developed. To facilitate the planning of lakeshore restoration plans, it becomes necessary to conduct studies focusing on the development of relationships between water quality and landscape factors within the lakeshore zone in different regions. In this study, spatio-temporal patterns of water quality of 49 lakes in Western Jilin Province, China, were determined through field monitoring from 2015 to 2019. Multivariate statistical methods were applied to quantitatively identify the relationships between lakes water quality and landscape factors within lakeshore zones of different widths. The results indicated that nitrogen (N) contributed more to eutrophication, while fluoride concentrations were found to be abnormally high. Furthermore, the width of the lakeshore zone was found to have a significant impact on water quality, with a critical width of 150 m having the greatest effect. Cropland and saline land explained almost 50% of the water quality variability throughout different seasons. The results also revealed that dual control of N and phosphorus (P) will be required to prevent eutrophication in the study area. Agricultural activities and severe soil salinization were identified as the main causes of diffuse pollution. The establishment of a width threshold identification framework for lakeshore zones is not only of great significance for development of scientific and acceptable restoration plans for lakeshore vegetation filters in ecologically vulnerable areas of western Jilin, but should also provide an effective and user-friendly tool for implementing diffuse pollution control.

There are a considerable number of discussions aimed at analyzing microbial communities and their functions during the composting process. However, microbial succession under copper (Cu) and tetracycline (TCH)-stressed conditions has received less attention. Thus, this work analyzed the bacterial and fungal structures with high-throughput sequencing in Cu/TCH-amended composting (Cu: 0, 100, and 500 mg/kg; TCH: 0, 50, and 300 mg/kg), and the dominating controls on microbial diversity were identified using redundancy analysis (RDA) and structural equation models (SEMs). Low-concentration Cu increased the peak temperature (57°C) at the thermophilic phase. Composting phase-derived changes in bacterial and fungal communities were significant, while Cu and TCH showed a remarkable influence on fungi but not on bacteria. Cu and TCH inhibited Firmicutes' activity while promoting Actinobacteriota growth. Low-concentration Cu and TCH had a negative effect on Basidiomycota in the thermophilic phase and a positive influence on Chytridiomycota in the mature phase. TOC and TN were primary controls on the changes in microbial communities. NH4+-N and NO3--N were more beneficial to fungi with a contribution proportion of 42.13 and 16.85%, respectively. These findings could provide theoretical guidance for the directional research on microbial inoculants.

BackgroundTelerehabiliation has been shown to have great potential in expanding access to rehabilitation services, enhancing patients’ quality of life, and improving clinical outcomes. Stationary biking exercise can serve as an effective aerobic component of home-based physical rehabilitation programs. Remote monitoring of biking exercise provides necessary safeguards to ensure exercise adherence and safety in patients' homes. The scalability of the current remote monitoring of biking exercise solutions is impeded by the high cost that limits patient access to these services, especially among older adults with chronic health conditions. ObjectiveThe aim of this project was to design and test two low-cost wireless interfaces for the telemonitoring of home-based biking exercise. MethodsWe designed an interactive biking system (iBikE) that comprises a tablet PC and a low-cost bike. Two wireless interfaces to monitor the revolutions per minute (RPM) were built and tested. The first version of the iBikE system uses Bluetooth Low Energy (BLE) to send information from the iBikE to the PC tablet, and the second version uses a Wi-Fi network for communication. Both systems provide patients and their clinical teams the capability to monitor exercise progress in real time using a simple graphical representation. The bike can be used for upper or lower limb rehabilitation. We developed two tablet applications with the same graphical user interfaces between the application and the bike sensors but with different communication protocols (BLE and Wi-Fi). For testing purposes, healthy adults were asked to use an arm bike for three separate subsessions (1 minute each at a slow, medium, and fast pace) with a 1-minute resting gap. While collecting speed values from the iBikE application, we used a tachometer to continuously measure the speed of the bikes during each subsession. Collected data were later used to assess the accuracy of the measured data from the iBikE system. ResultsCollected RPM data in each subsession (slow, medium, and fast) from the iBikE and tachometer were further divided into 4 categories, including RPM in every 10-second bin (6 bins), RPM in every 20-second bin (3 bins), RPM in every 30-second bin (2 bins), and RPM in each 1-minute subsession (60 seconds, 1 bin). For each bin, the mean difference (iBikE and tachometer) was then calculated and averaged for all bins in each subsession. We saw a decreasing trend in the mean RPM difference from the 10-second to the 1-minute measurement. For the 10-second measurements during the slow and fast cycling, the mean discrepancy between the wireless interface and tachometer was 0.67 (SD 0.24) and 1.22 (SD 0.67) for the BLE iBike, and 0.66 (SD 0.48) and 0.87 (SD 0.91) for the Wi-Fi iBike system, respectively. For the 1-minute measurements during the slow and fast cycling, the mean discrepancy between the wireless interface and tachometer was 0.32 (SD 0.26) and 0.66 (SD 0.83) for the BLE iBike, and 0.21 (SD 0.21) and 0.47 (SD 0.52) for the Wi-Fi iBike system, respectively. ConclusionsWe concluded that a low-cost wireless interface provides the necessary accuracy for the telemonitoring of home-based biking exercise.

Available information on the microbial mechanisms associated with heavy metal (HM) passivation during co-composting amended with phosphate rock (PR) remains limited. Thus, this study investigated the dynamic changes in bacterial communities and HM-fractions (Zn, Cu, Cd, Cr and Pb) during swine manure composting with maize straw, and ascertained the bacterial influence on HM-passivation. The results demonstrated that the addition of PR improved HM-passivation, especially for Zn and Cd, with their bioavailability factors (BFs) reduced by 247.41 and 176.25%, respectively. As for bacterial communities, the proportion of Firmicutes decreased, while the proportions of Proteobacteria, Bacteroidetes, Deinococcus-Thermus and Gemmatimonadetes increased in all treatments. PR significantly changed the primary bacterial phyla in the thermophilic phase. Bacteroidetes were the main bacterial component controlling the passivation of Zn, Cu and Cr, while Deinococcus-Thermus mainly regulated the mobility of Zn and Pb, and Proteobacteria only dominated the transformation among Cd-fractions. These results may provide a reference for the use of HM-passivation techniques during composting.

Rare‐earth (RE) silicates environmental barrier coatings (EBCs) are prone to accelerate failure resulted from molten calcium–magnesium–aluminum silicate (CMAS), which presents significant challenges to the design and development of durable EBCs. In this study, X1‐Gd2SiO5 and X2‐Er2SiO5 coatings were explored on their corrosion resistance to CMAS melts with different Ca/Si ratios (1.1, 0.75, 0.64, and 0.42) at 1350°C for 25 and 50 h, respectively. Results showed that with the Ca/Si ratio increasing, CMAS viscosity decreased and a more intense corrosion reaction with coatings occurred. Garnet phase was only observed in X2‐Er2SiO5 coating corroded by CMAS with high Ca/Si ratios, which could be beneficial for improving corrosion resistance. The X2‐Er2SiO5 phase, which is composed of [SO4] and [REO6]/[REO7] polyhedrons, exhibits better corrosion resistance due to its more stable crystal structure, lower reactivity with CMAS, and the radius difference between the RE ions and Ca2+. [ABSTRACT FROM AUTHOR]

Abstract Ecological stoichiometry is an important indicator presenting multiple elements balance in agro-ecosystems. However, information on microbial communities and nutrient stoichiometry in soil aggregate fractions under different croplands (rice, maize, and soybean fields) remains limited. Thus, this study investigated water-stable aggregate structure and their internal nutrient stoichiometry under different croplands and ascertain their interaction mechanism with microbial communities. The results showed that no significant difference on the carbon-to-nitrogen ratio (C:N) in soil aggregate fractions was observed, while the carbon-to-phosphorus ratio (C:P) and the nitrogen-to-phosphorus ratio (N:P) were ranked as rice field > maize field > soybean field, and were higher in mega-aggregates (ME, > 1 mm). General fatty acid methyl ester (FAME), Gram-positive bacteria (G+), and Gram-negative bacteria (G−) were predominant microbial communities in all croplands and tented to condense into coarse-aggregates. Redundancy analysis (RDA) demonstrated that N:P ratio was primary environmental controls on the distribution of soil microorganisms. In the Sanjiang Plain, N was the nutrient element limiting agro-ecosystem productivity, and rice cultivation is expected to improve the N-limited nutrient status.

Abstract Background Myocardial dysfunction is one of the most common complications of multiple organ failure in septic shock and significantly increases mortality in patients with sepsis. Although many studies having confirmed that helminth-derived proteins have strong immunomodulatory functions and could treat inflammatory diseases, there is no report on the therapeutic effect of Schistosoma japonicum-produced cystatin (Sj-Cys) on sepsis-induced cardiac dysfunction. Methods A model of sepsis-induced myocardial injury was established by cecal ligation and puncture (CLP) in mice. Upon CLP operation, each mouse was intraperitoneally treated with 10 µg of recombinant Sj-Cys (rSj-Cys). Twelve hours after CLP, the systolic and diastolic functions of the left ventricular were examined by echocardiography. The levels of myoglobin (Mb), cardiac troponin I (cTnI), N-terminal pro-Brain Natriuretic peptide (NT-proBNP) in sera, and the activity of myeloperoxidase (MPO) in cardiac tissues were examined as biomarkers for heart injury. The heart tissue was collected for checking pathological changes, macrophages and pro-inflammatory cytokine levels. To address the signaling pathway involved in the anti-inflammatory effects of rSj-Cys, myeloid differentiation factor 88 (MyD88) was determined in heart tissue of mice with sepsis and LPS-stimulated H9C2 cardiomyocytes. In addition, the therapeutic effects of rSj-Cys on LPS-induced cardiomyocyte apoptosis were also detected. The levels of M1 biomarker iNOS and M2 biomarker Arg-1 were detected in heart tissue. The pro-inflammatory cytokines TNF-α and IL-6, and regulatory cytokines IL-10 and TGF-β were measured in sera and their mRNA levels in heart tissue of rSj-Cys-treated mice. Results After rSj-Cys treatment, the sepsis-induced heart malfunction was largely improved. The inflammation and injury of heart tissue were significantly alleviated, characterized as significantly decreased infiltration of inflammatory cells in cardiac tissues and fiber swelling, reduced levels of Mb, cTnI and NT-proBNP in sera, and MPO activity in heart tissue. The therapeutic efficacy of rSj-Cys is associated with downregulated pro-inflammatory cytokines (TNF-α and IL-6) and upregulated regulatory inflammatory cytokines (IL-10 and TGF-β), possibly through inhibiting the LPS-MyD88 signal pathway. Conclusions RSj-Cys significantly reduced sepsis-induced cardiomyopathy and could be considered as a potential therapeutic agent for the prevention and treatment of sepsis associated cardiac dysfunction.

We propose and demonstrate an effective and simple multi-wavelength spatiotemporal mode-locked (STML) laser. The laser introduces a multimode interference (MMI) effect using the core diameter mismatch of the fibers, thus enabling simultaneous mode-locking at multiple wavelengths. For the multi-wavelength mode-locking, each wavelength exists a matching pulse sequence, and different wavelengths can possess the same pulse state or different states. Meanwhile, at the dual-wavelength operation, by adjusting the polarization controllers, not only the central wavelength can be continuously adjusted from 1552.93 nm to 1572.64 nm, but also the wavelength interval can be adjusted from 2 nm to 19 nm, which benefits from the tunability of the MMI effect. Moreover, the spectral channels can be consecutively increased from 2 to 4. The obtained results provide a platform for understanding and studying the multi-wavelength STML properties. This flexible all-fiber laser has great potential for applications in the fields of optical signal processing, fiber sensing, and information coding.

Despite remarkable progress made in human genome-wide association studies, there remains a substantial gap between statistical evidence for genetic associations and functional comprehension of the underlying mechanisms governing these associations. As a means of bridging this gap, we performed genomic analysis of blood pressure (BP) and related phenotypes in spontaneously hypertensive rats (SHR) and their substrain, stroke-prone SHR (SHRSP), both of which are unique genetic models of severe hypertension and cardiovascular complications. By integrating whole-genome sequencing, transcriptome profiling, genome-wide linkage scans (maximum n=1415), fine congenic mapping (maximum n=8704), pharmacological intervention and comparative analysis with transcriptome-wide association study (TWAS) datasets, we searched causal genes and causal pathways for the tested traits. The overall results validated the polygenic architecture of elevated BP compared with a non-hypertensive control strain, Wistar Kyoto rats (WKY); e.g. inter-strain BP differences between SHRSP and WKY could be largely explained by an aggregate of BP changes in seven SHRSP-derived consomic strains. We identified 26 potential target genes, including rat homologs of human TWAS loci, for the tested traits. In this study, we re-discovered 18 genes that had previously been determined to contribute to hypertension or cardiovascular phenotypes. Notably, five of these genes belong to the kallikrein–kinin/renin–angiotensin systems (KKS/RAS), in which the most prominent differential expression between hypertensive and non-hypertensive alleles could be detected in rat Klk1 paralogs. In combination with a pharmacological intervention, we provide in vivo experimental evidence supporting the presence of key disease pathways, such as KKS/RAS, in a rat polygenic hypertension model.

To improve the adsorption efficiency of pollutants by biochar, preparing graphene-like biochar (GBC) or nitrogen-doped biochar are two commonly used methods. However, the difference in the nitrogen doping (N-doping) effects upon the adsorption of pollutants by pristine biochar (PBC) and GBC, as well as the underlying mechanisms, are still unclear. Take the tetracycline (TC) as an example, the present study analyzed the characteristics of the adsorption of TCs on biochars (PBC, GBC, N-PBC, N-GBC), and significant differences in the effects of N-doping on the adsorption of TCs by PBC and GBC were consistently observed at different solution properties. Specifically, N-doping had varied effects on the adsorption performance of PBC, whereas it uniformly improved the adsorption performance of GBC. To interpret the phenomenon, the N-doping upon the adsorption was revealed by the QSAR model, which indicated that the pore filling (VM) and the interactions between TCs with biochars (Ead-v) were found to be the most important two factors. Furthermore, the density functional theory (DFT) results demonstrated that N-doping slightly affects biochar's chemical reactivity. The van der Waals (vdWs) and electrostatic interactions are the main forces for TCs-biochars interactions. Moreover, N-doping mostly strengthened the electrostatic interactions of TCs-biochars, but the vdWs interactions of most samples remained largely unaffected. Overall, the revealed mechanism of N-doping on TCs adsorption by biochars will enhance our knowledge of antibiotic pollution remediation. [ABSTRACT FROM AUTHOR]