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The unique composite gradient structure of bamboo has made it widely recognized as an extremely efficient natural structure and material, endowing it with exceptional flexibility and resilience. This enabled bamboo to withstand the forces of wind and snow without fracturing. In this paper, the inherent structural characteristics of bamboo were examined in order to extract its biological advantages through experimental methods. Then, the structural characteristics of bamboo in its vertical and radial directions served as the respective inspiration for two bionic applications, which were further analyzed and optimized using finite element analysis to accurately evaluate their bearing capacities. It can be found that the density of vascular bundles increased proportionally with the height of the bamboo stem, while the circumference exhibited a linear decrease. The wall thickness of the bamboo decreased and stabilized after reaching a height of 10 m. The distribution of nodes exhibited a nearly symmetrical pattern from the base to the top of the bamboo stem. The tapering of the bamboo culm exhibited a non-linear pattern with height, characterized by an initial decrease followed by a slight increase ranging from 0.004 to 0.010. The vascular bundles in bamboo exhibited a functional gradient distribution, which had a 6:3:2 distribution ratio of vascular bundles in the wall’s dense, transition, and sparse areas, respectively. The bionic cantilever beam incorporated characteristics of a hollow structure, a non-uniform distribution of nodes, and a certain amount of tapering, which effectively enhanced its flexural performance compared to the traditional ones. The thin-wall tube, featuring a “dendritic” partial pressure structure, demonstrated exceptional lateral compressive performance in transverse compression, particularly when the tube incorporated a gradient distribution of partition numbers and layer spacing.

In an era where countries worldwide are emphasizing the process of educational informatization, traditional experimental teaching methods encounter inherent limitations, such as constraints related to the availability of experimental sites and the amount of experimental equipment. Consequently, it becomes a challenge to provide students with an unconstrained, open, and collaborative experimental environment. The digital twin, as a pivotal technology for achieving interactive mapping of the physical world and the information world, possesses attributes characterized by real time interactivity and the seamless fusion of virtual and tangible elements. As a result, various virtual simulation experimental teaching platforms grounded in digital twin technology are now extensively integrated into talent development initiatives. In the context of the “Production Planning and Control” course at Harbin Institute of Technology (HIT), the virtual simulation experimental teaching method is examined, leading to the creation of a virtual simulation instructional platform that blends the virtual and tangible realms, thanks to the foundation of digital twin technology. The virtual simulation experimental teaching platform detailed in this paper, specifically designed for optimizing scheduling within assembly line workshops, represents a pioneering model practice in the integration of digital twin technology into workshop-based experimental instruction and assumes an influential role in enhancing students’ grasp of theoretical knowledge and their capacity for practical innovation.

A novel heterogeneous Fenton-like photocatalyst, Fe-doped graphitic carbon nitride (Fe-g-C3N4), was produced by facile two-step calcination method. This Fe–g–C3N4 catalyzed rhodamine B degradation in the presence of H2O2 accompanied with visible light irradiation. transmission electron microscopy(TEM), x-ray diffraction (XRD), FT-IR, x-ray photoelectron spectroscopy (XPS), and photoluminescence fluorescent spectrometer (PL) characterization analysis methods were adopted to evaluate the physicochemical property of samples. It can be observed that the Fe-g-C3N4 exhibited excellent photocatalytic Fenton-like activity at a wide pH range of 3–9, with rhodamine B(RhB) degradation efficiency up to 95.5% after irradiation for 45 min in the presence of 1.0 mM H2O2. Its high activity was ascribed to the formation of Fe–N ligands in the triazine rings that accelerated electron movement driving the Fe(III)/Fe(II) redox cycle, and inhibited photo-generated electron hole re-combinations for continuous generation of reactive oxygen species by reactions between Fe(II) and H2O2. The main active oxygen species were hydroxyl radicals, followed by superoxide radicals and hole electrons. This produced catalyst of Fe–g–C3N4 shows excellent reusability and stability, and can be a promising candidate for decontamination of wastewater.

Abstract Background Innovative attempt to explore the feasibility and accuracy of using indocyanine green fluorescence (ICGF) to identify the intersegmental plane by the target segmental veins preferential ligation during thoracoscopic segmentectomy. Methods A retrospective analysis was conducted on clinical data of 32 consecutive patients who underwent thoracoscopic segmentectomy with intersegmental plane identification using both ICGF and inflation-deflation method after target segmental veins prioritized blocking at Nanjing Chest Hospital from December 2022 to June 2023. Preoperative three-dimensional reconstruction was used to identify the target segment and the anatomical structure of the arteries, veins, and bronchi. After ligating the target segmental veins during surgery, the first intersegmental plane was immediately identified and marked with an electrocoagulation device using an inflation-deflation method. Subsequently, the second intersegmental plane was determined using the ICGF method. Finally, the consistency of the two intersegmental planes was evaluated. Results All the 32 patients successfully completed thoracoscopic segmentectomy without ICG-related complications and perioperative death. The average operation time was (98.59 ± 20.72) min, the average intraoperative blood loss was (45.31 ± 35.65) ml, and the average postoperative chest tube removal time was (3.5 ± 1.16) days. The average postoperative hospital stay was (4.66 ± 1.29) days, and the average tumor margin width was (26.96 ± 5.86) mm. The intersegmental plane determined by ICGF method was basically consistent with inflation-deflation method in all patients. Conclusion The ICGF can safely and accurately identify the intersegmental plane by target segmental veins preferential ligation during thoracoscopic segmentectomy, which is a beneficial exploration and important supplement to the simplified thoracoscopic anatomical segmentectomy.

Abstract Unravelling biosphere feedback mechanisms is crucial for predicting the impacts of global warming. Soil priming, an effect of fresh plant-derived carbon (C) on native soil organic carbon (SOC) decomposition, is a key feedback mechanism that could release large amounts of soil C into the atmosphere. However, the impacts of climate warming on soil priming remain elusive. Here, we show that experimental warming accelerates soil priming by 12.7% in a temperate grassland. Warming alters bacterial communities, with 38% of unique active phylotypes detected under warming. The functional genes essential for soil C decomposition are also stimulated, which could be linked to priming effects. We incorporate lab-derived information into an ecosystem model showing that model parameter uncertainty can be reduced by 32–37%. Model simulations from 2010 to 2016 indicate an increase in soil C decomposition under warming, with a 9.1% rise in priming-induced CO2 emissions. If our findings can be generalized to other ecosystems over an extended period of time, soil priming could play an important role in terrestrial C cycle feedbacks and climate change.

In this study, polyimide (PI) and polysulfonamide (PSA) were used as base materials, and polyethylene glycol (PEG) was added to successfully prepare PI/PSA/PEG nanofiber membranes through electrospinning technology. Subsequently, water etching was performed on the membranes, utilizing the water solubility of PEG to form the rough wrinkled structure, further enhancing the surface hydrophobicity. The experimental results showed that under the conditions of a spinning voltage of 10 kV, PI/PSA mass fraction of 15 wt.%, and PEG-to-PI/PSA mass ratio of 1/3, the obtained fiber membranes exhibit a uniform morphology (an average diameter of 0.73 µm) and excellent hydrophobicity (the initial water contact angle (WCA) reaching 130.4°). After PEG water etching, the surface of the PI/PSA/PEG hydrophobic membranes formed the rough wrinkled structure, which not only improved their mechanical properties but also further enhanced their hydrophobicity (the initial WCA increasing to 137.9°). Hence, fiber membranes are expected to have broad application prospects in fields such as waterproofing and moisture permeability.

Background. The microRNA (miR)--mRNA axes involved in oxidized low-density lipoprotein (ox-LDL)-induced vascular smooth muscle cells (VSMCs) proliferation/apoptosis imbalance need to be investigated in more detail. Objectives. To investigate the function and any relevant changes to miR--mRNA axes in the ox-LDL-induced proliferation/apoptosis imbalance in VSMCs. Materials and methods. Human VSMCs were cultured and treated with ox-LDL in vitro. The differentially expressed (DE) miRs and mRNAs in VSMCs following 48-h ox-LDL treatment were detected using RNA sequencing. Candidate miRs and mRNAs were further selected, based on comprehensive bioinformatics analysis. Changes in the expression of candidate miRs and mRNAs in ox-LDL-treated VSMCs were confirmed with quantitative real-time polymerase chain reaction (RT-qPCR) and western blot. The inhibitory effect of candidate miRs on mRNAs were demonstrated using a dual luciferase reporter assay. The functional role of candidate miRs and mRNAs on proliferation, cell cycle and apoptosis of VSMCs were estimated using cell couting kit-8 (CCK-8) and flow cytometry assays, respectively. Results. The RNA sequencing data indicated that 577 mRNAs and 81 miRs were significantly upregulated in VSMCs following ox-LDL treatment. Gene function and pathway enrichment analysis suggested that the DE-mRNAs and miRs participate in the regulation of proliferation, cell cycle and apoptosis. Increased expression of DLX5 with decreasing miR-124-3p levels were confirmed in ox-LDL-treated VSMCs. The miR-124-3p could inhibit the DLX5 level by binding the 3' UTR of DLX5 mRNA. Functional analysis showed that the alteration of miR-124-3p/DLX5 expression mediated the effect of ox-LDL on VSMCs proliferation/apoptosis imbalance. Conclusions. The ox-LDL affects the VSMC proliferation/apoptosis balance via the miR-124-3p/DLX5 axis, which results in VSMC hyperproliferation. The miR-124-3p/DLX5 axis might serve as a therapeutic molecular target to reverse the effect of ox-LDL and prevent atherosclerosis (AS) development and progression. [ABSTRACT FROM AUTHOR]

Manganese pollution particularly in the form of dissolved Mn2+ is an important problem in groundwater treatment. The main approaches for Mn2+ removal from groundwater are chemical catalytic oxidation and biological oxidation. Their relative attribution to Mn2+ removal and relationship has not been clarified at the matured stage. An influent of water containing 2.0 and 4.0 mg/L Mn2+ was filtered through columns filled with manganese sand that had either been inoculated with a manganese-adapted microbial community or had been pre-oxidized with potassium permanganate. Either treatment resulted in good manganese removal capacities that maintained a final concentration in the effluent below 0.05 mg Mn2+/L at two concentrations for a period of 130 d. Among the matured period, the direct contribution rate of biological manganese removal was less than 20%. During operation, biological induction and chemical induction were both responsible for the formation of hexagonal Birnessite-type manganese oxide, whose physical characteristics were characterized and determined. Biological oxidation and chemical catalytic oxidation in the maturation of filter media were interlinked through the formation of Birnessite-type manganese oxide. Manganese removal during maturation was mainly attributed to cyclic autocatalysis rather than biological factors. [ABSTRACT FROM AUTHOR]

The ever-increasing applications of metabarcoding analyses for environmental samples demand a well-designed assessment of the stability of DNA and RNA contained in cells that are deposited or buried in marine sediments. We thus conducted a qPCR quantification of the DNA and RNA in the vegetative cells of three microalgae entrapped in facsimile marine sediments and found that >90% of DNA and up to 99% of RNA for all microalgal species were degraded within 60 days at 4 °C. A further examination of the potential interference of the relic DNA of the vegetative cells with resting cyst detection in sediments was performed via a metabarcoding analysis in artificial marine sediments spiked with the vegetative cells of two Kareniaceae dinoflagellates and the resting cysts of another three dinoflagellates. The results demonstrated a dramatic decrease in the relative abundances of the two Kareniaceae dinoflagellates in 120 days, while those of the three resting cysts increased dramatically. Together, our results suggest that a positive detection of microalgae via metabarcoding analysis in DNA or RNA extracted from marine sediments strongly indicates the presence of intact or viable cysts or spores due to the rapid decay of relic DNA/RNA. This study provides a solid basis for the data interpretation of metabarcoding surveys, particularly in resting cyst detection.

Abstract The Hippo signalling pathway is dysregulated across a wide range of cancer types and, although driver mutations that directly affect the core Hippo components are rare, a handful is found within pleural mesothelioma (PM). PM is a deadly disease of the lining of the lung caused by asbestos exposure. By pooling the largest‐scale clinical datasets publicly available, we here interrogate associations between the most prevalent driver mutations within PM and Hippo pathway disruption in patients, while assessing correlations with a variety of clinical markers. This analysis reveals a consistent worse outcome in patients exhibiting transcriptional markers of YAP/TAZ activation, pointing to the potential of leveraging Hippo pathway transcriptional activation status as a metric by which patients may be meaningfully stratified. Preclinical models recapitulating disease are transformative in order to develop new therapeutic strategies. We here establish an isogenic cell‐line model of PM, which represents the most frequently mutated genes and which faithfully recapitulates the molecular features of clinical PM. This preclinical model is developed to probe the molecular basis by which the Hippo pathway and key driver mutations affect cancer initiation and progression. Implementing this approach, we reveal the role of NF2 as a mechanosensory component of the Hippo pathway in mesothelial cells. Cellular NF2 loss upon physiological stiffnesses analogous to the tumour niche drive YAP/TAZ‐dependent anchorage‐independent growth. Consequently, the development and characterisation of this cellular model provide a unique resource to obtain molecular insights into the disease and progress new drug discovery programs together with future stratification of PM patients.

In this study, an experimental study aimed at optimizing the factors affecting the regeneration amount of 4-chlorophenol (4-CP) from spent powdered activated carbon (PAC) is presented. For this response surface methodology (RSM) with Box-Behnken design was applied, which identified four variables (acoustic density, NaOH concentration, spent PAC dosage and ethanol concentration) in batch experiments. The physicochemical characteristics of the regenerated PAC under the optimal desorption condition was evaluated using thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and scanning electron microscopy, as compared with the virgin and spent PACs. Among the four variables, acoustic density and ethanol concentration (v/v, %) had stronger effect on the 4-CP desorption (p < 0.001). The predicted optimal 4-CP desorbing amount was 97.43 mg g-1, and this matched well the observed performance of (96.94 ± 0.70) mg g-1, obtained by acoustic density of 0.36 W mL-1, NaOH concentration of 0.10 mol L-1, spent PAC dosage of 0.93 g L-1 and ethanol concentration (v/v) of 24%. The result of thermogravimetric pyrolysis profiles of regenerated PAC confirmed that the adsorption behavior of 4-CP exhibited a chemisorption feature and desorption process was dominated by chemical reaction. Analysis of FTIR, pore structure and BET surface area demonstrated that ultrasound mainly acted on the surface functionalities, macro-pore and meso-pore structure of PAC. Additionally, the SEM images indicated that cavitation effect affected the surface roughness and surface cavities of PAC. The results here provided an insight into the application of ultrasound to regenerate saturated PAC with 4-CP. [ABSTRACT FROM AUTHOR]

A series of Bi-Ti composited photocatalysts with different molar ratio of Bi/Ti (0.01:1(1%), 0.02:1(2%), 0.04:1(4%), and 0.05:1(5%)) and calcination temperature (400°C, 500°C, and 600°C) were prepared by sol-hydrothermal method. The properties of as-prepared photocatalysts were characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photo-electron spectroscopy, Brunauer-Emmett-Teller, and ultraviolet-visible diffuse reflection spectroscopy. The selected photocatalyst (Bi-Ti-4%-600°C) was prepared under Bi/Ti molar ratio of 4% and calcination temperature of 600°C. Experimental variables during photocatalytic degradation were optimized for catalyst dosage, solution pH, initial bisphenol A (BPA) concentration, coexisting anions, and light source wavelength. Under optimal conditions of 1.0 g L-1 catalyst, pH 3, 30 mg L-1 initial BPA concentration, the degradation rate of BPA could reach up to 100% at 150 min under visible light irradiation. Compared with self-made pure TiO2 and commercially available P25, Bi-Ti-4%- 600°C displayed an excellent photocatalytic activity for BPA degradation. Bi-Ti photocatalyst had a smaller crystal size, larger specific surface area, stronger visible light absorption ability, and lower band gap energy than self-made pure TiO2. Four intermediates of BPA degradation were identified and a possible degradation pathway was proposed. [ABSTRACT FROM AUTHOR]

Abstract Nitrogen (N) fertilization significantly affects soil extracellular oxidases, agents responsible for decomposition of slow turnover and recalcitrant soil organic carbon (SOC; e.g., lignin), and consequently influences soil carbon sequestration capacity. However, it remains unclear how soil oxidases mediate SOC sequestration under N fertilization, and whether these effects co‐vary with plant type (e.g., bioenergy crop species). Using a spatially explicit design and intensive soil sampling strategy under three fertilization treatments in switchgrass (SG: Panicum virgatum L.) and gamagrass (GG: Tripsacum dactyloides L.) croplands, we quantified the activities of polyphenolic oxidase (PHO), peroxidase (PER), and their sum associated with recalcitrant C acquisition (OX). The fertilization treatments included no N fertilizer input (NN), low N input (LN: 84 kg N ha−1 year−1 in urea), and high N input (HN: 168 kg N ha−1 year−1 in urea). Besides correlations between soil oxidases and SOC (formerly published), both descriptive and geostatistical approaches were applied to evaluate the effects of N fertilization and crop type on soil oxidases activities and their spatial distributions. Results showed significantly negative correlations between soil oxidase activities and SOC across all treatments. The negative relationship of soil oxidases and SOC was also evident under N fertilization. First, LN significantly depressed oxidases in both mean activities and spatial heterogeneity, which corresponded to increased SOC in SG (though by 5.4%). LN slightly influenced oxidases activities and their spatial heterogeneity, consistent with insignificant changes of SOC in GG. Second, HN showed trends of decrease in soil oxidase activities, which aligned with the significantly enhanced SOC in both croplands. Overall, this study demonstrated that soil oxidase activities acted as sensitive and negative mediators of SOC sequestration in bioenergy croplands and optimizing fertilizer use particularly in switchgrass cropland can improve for both carbon sequestration and environmental benefit.

The effects of organic and conventional production systems on crop productivity have been greatly explored, but their effects on soil microbial processes were often neglected. A comparative field study of organic and conventional production systems was conducted at the Tennessee State University research farm to determine soil heterotrophic respiration and microbial biomass carbon. Leafy green vegetables were grown in a conventional production system in an open field, and they were grown in an organic production system, using three different row covers (agribon cloth, insect net, and plastic), and in an open field. Soil samples (0-15cm) were collected from the two production systems. Soil heterotrophic respiration rate (RH), microbial biomass carbon (MBC), and biomass-specific heterotrophic respiration rate (the inverse is used as a proxy for microbial carbon use efficiency) were quantified. The results showed that the conventional production system significantly increased RH relative to the organic system. Organic production system, however, significantly enhanced MBC and reduced biomass-specific respiration rate indicating an increase in carbon use efficiency. Although MBC remained unchanged among the row covers, insect net increased RH and biomass-specific heterotrophic respiration rate. Our results suggest that the organic production system not only promoted soil microbial abundance but also limited soil heterotrophic respiration to the atmosphere governed by the elevated carbon use efficiency.

As the climate warms, soil carbon stores will likely be degraded by microbes and released as CO2, but these predictions are based on laboratory incubations that might not reflect real rates. Here the authors optimize model projections using dozens of short- and long-term incubations in forest and grasslands.

In this study, to explore the demand characteristics of autonomous coaches in mixed traffic flow, two sections of an expressway were selected for vehicle experiments. With personification as the goal, sensors of the ego-vehicle were used to collect naturalistic car-following behavior data of surrounding coaches. After analyzing the naturalistic car-following data, car-driving behavior characteristics of the coach drivers were acquired. The analysis results indicate that the overall car-following processes of coaches tend to be relatively stable, and most of the car-following processes are in the conditions of higher velocity, smaller acceleration, and smaller relative velocity than the front vehicle. The expected following spacing and time headway of the coach drivers increase with the increase of velocity. By analysis and comparison with existing safe following models, it is found that while the safety and the warning rate based on the car-following coach safety distance model are higher, the warning rate of the car-following time headway model at the relatively higher velocity is lower. The coach safety distance model established in this study considers the car-following risk and the acceptance rate of the drivers to the warning system. This model conforms to the driver's car-following characteristics and fulfills the requirements of collision avoidance. Applying the safety distance model to the autonomous coach would effectively improve the anthropopathic behavior characteristics of the autonomous coach. Additionally, the abnormality caused by the interference of other vehicles in mixed traffic flow of autonomous and human vehicles is successfully avoided under the premise of ensuring the safe driving of the autonomous coach.

This paper proposes a method for visibility detection based on the recognition of the preceding vehicle's taillight signals using in-vehicle camera and millimeter-wave (mm-W) radar. First, we design two methods of vehicle identification. One is to use Haar-like features and an AdaBoost algorithm to train the vehicle classifier, which is mainly used to identify vehicles without turning on the taillights. The other is to identify vehicles with taillights on by means of taillight segmentation. The two identification methods are combined with a Discriminative Scale Space Tracker (DSST) to track the vehicle in the image acquired by vehicle camera and to measure anthropic visibility with mm-W radar. In addition, we drove a test vehicle on a foggy highway and collected experimental data through in-vehicle camera and mm-W radar. The experimenter observed the movement of the vehicle in front until it disappeared from the field of vision and recorded the distance of the vehicle in front measured by radar at that time as human visibility, which was also used as the ground truth to verify the accuracy of the proposed visibility detection method. The experimental results show that the visibility measured by the proposed algorithm is essentially consistent with the visibility obtained by human eyes, that is, the visibility of vehicles with no taillights, clearance lamp, emergency flasher, or fog lamp tends to rise, with an average accuracy of 88%, 91%, 90%, and 95%, respectively. In contrast to the traditional visibility measurement, this method mainly measures the maximum distance that the driver can observe when the front vehicle is not turned on or different taillights are turned on.

As the transmembrane receptor of Netrin-1, the tumor suppressor gene Unc-5 Netrin Receptor C (UNC5C) can trigger apoptosis. Although its tumor suppressor effects have been demonstrated in solid tumors such as colon cancer, there is still a lack of systematic research on its expression regulation mechanism. To address this need, we analyzed datasets from The Cancer Genome Atlas (TCGA) database, including multi-omics data for 32 types of cancers and 10,967 cases. Analysis of these data revealed a trend of significantly decreased UNC5C expression in 16 types of solid tumors. Additionally, low UNC5C expression is related to poor prognosis of five types of tumors and restoring the expression of UNC5C can effectively inhibit the proliferation potential of renal cancer cells. Promoter DNA methylation, chromatin remodeling-mediated epigenetic regulation, transcriptional inhibition, RNA-binding protein and miRNA-mediated post-transcriptional inhibition, genetic changes caused by deep deletion and truncated mutations, and ubiquitinating enzyme-mediated protein degradation can synergistically cause the down-regulation of UNC5C expression in solid tumors. This study is the first to analyze the comprehensive molecular mechanism of down-regulation of the tumor suppressor gene UNC5C from multiple dimensions using pan-cancer data. Our results suggest that analyses of gene expression regulation relying on computational biological methods may help guide the targeted therapy of tumor suppressor gene reactivation.

BackgroundBladder cancer is a common malignant tumor characterized by high mortality and high management costs; however, it lacks useful molecular prognostic markers. Tribbles pseudokinase 3 (TRIB3) is a pseudokinase that participates in cell tumor progression and metabolism and whose function in bladder cancer is not precisely known.Main MethodsWe downloaded transcriptome data and clinical data of bladder cancer from associated databases and extracted the expression matrix of TRIB3 for multiple bioinformatics analysis. RT-PCR detected the expression of TRIB3 in bladder cancer cells. After knockdown of TRIB3 with siRNA, we investigated TRIB3 function using CCK8, Cell Cycle and Transwell assays.Key FindingsKaplan–Meier analysis of TRIB3 in the four cohorts showed that high expression of TRIB3 correlated with poor outcome. Expression of TRIB3 positively correlated with stage and grade and down-regulation of TRIB3 expression significantly inhibited proliferation, migration and cell cycle of bladder cancer cells.SignificanceTRIB3 is a potential prognostic marker and therapeutic target. It can be used to individualize the treatment of bladder cancer.

Nitrogen (N) fertilization affects bioenergy crop growth and productivity and consequently carbon (C) and N contents in soil, it however remains unclear whether N fertilization and crop type individually or interactively influence soil organic carbon (SOC) and total N (TN). In a three-year long fertilization experiment in switchgrass (SG: Panicum virgatum L.) and gamagrass (GG: Tripsacum dactyloides L.) croplands in Middle Tennessee USA, soil samples (0-15cm) were collected in plots with no N input (NN), low N input (LN: 84 kg N ha-1 yr-1 in urea) and high N input (HN: 168 kg N ha-1 yr-1 in urea). Besides SOC and TN, the aboveground plant biomass was also quantified. In addition to a summary of published root morphology data based on a separated mesocosm experiment, the root leachable dissolved organic matter (DOM) of both crops was also measured using archived samples. Results showed no significant interaction of N fertilization and crop type on SOC, TN or plant aboveground biomass (ABG). Relative to NN, HN (not LN) significantly increased SOC and TN in both crops. Though SG showed a 15-68% significantly higher ABG than GG, GG showed a 9.3-12% significantly higher SOC and TN than SG. The positive linear relationships of SOC or TN with ABG were identified for SG. However, GG showed structurally more complex and less readily decomposed root DOM, a larger root volume, total root length and surface area than SG. Collectively, these suggested that intensive N fertilization could increase C and N stocks in bioenergy cropland soils but these effects may be more likely mediated by the aboveground biomass in SG and root chemistry and morphology in GG. Future studies are expected to examine the root characteristics in different bioenergy croplands under the field fertilization experiment.

Abstract The effects of intensive nitrogen (N) fertilizations on spatial distributions of soil microbes in bioenergy croplands remain unknown. To quantify N fertilization effect on spatial heterogeneity of soil microbial biomass carbon (MBC) and N (MBN), we sampled top mineral horizon soils (0-15 cm) using a spatially explicit design within two 15-m2 plots under three fertilization treatments in two bioenergy croplands in a three-year long fertilization experiment in Middle Tennessee, USA. The three fertilization treatments were no N input (NN), low N input (LN: 84 kg N ha−1 in urea) and high N input (HN: 168 kg N ha−1 in urea). The two crops were switchgrass (SG: Panicum virgatum L.) and gamagrass (GG: Tripsacum dactyloides L.). Results showed that N fertilizations little altered central tendencies of microbial variables but relative to LN, HN significantly increased MBC and MBC:MBN (GG only). HN possessed the greatest within-plot variances except for MBN (GG only). Spatial patterns were generally evident under HN and LN plots and much less so under NN plots. Substantially contrasting spatial variations were also identified between croplands (GG > SG) and among variables (MBN, MBC:MBN > MBC). This study demonstrated that spatial heterogeneity is elevated in microbial biomass of fertilized soils likely by uneven fertilizer application in bioenergy crops.

3D Printed biodegradable polymeric scaffolds are critical to repair a bone defect, which can provide the individual porous and network microenvironments for cell attachment and bone tissue regeneration. Biodegradable PCL/HA composites were prepared with the blending of poly(ε-caprolactone) (PCL) and hydroxyapatite nanoparticles (HA). Subsequently, the PCL/HA scaffolds were produced by the melting deposition-forming method using PCL/HA composites as the raw materials in this work. Through a serial of in vitro assessments, it was found that the PCL/HA composites possessed good biodegradability, low cell cytotoxicity, and good biocompatibility, which can improve the cell proliferation of osteoblast cells MC3T3-E1. Meanwhile, in vivo experiments were carried out for the rats with skull defects and rabbits with bone defects. It was observed that the PCL/HA scaffolds allowed the adhesion and penetration of bone cells, which enabled the growth of bone cells and bone tissue regeneration. With a composite design to load an anticancer drug (doxorubicin, DOX) and achieve sustained drug release performance, the multifunctional 3D printed PCL/HA/DOX scaffolds can enhance bone repair and be expected to inhibit probably the tumor cells after malignant bone tumor resection. Therefore, this work signifies that PCL/HA composites can be used as the potential biodegradable scaffolds for bone repairing.

To clarify the role of solubilized organics derived from drinking water treatment sludge (DWTS) in the elimination of natural organic matter (NOM) in the DWTS recycling process, a probe sonoreactor at a frequency of 25 kHz was used to solubilize the organics at varied specific energies. The coagulation behavior related to NOM removal in recycling the sonicated DWTS with and without solubilized organics was evaluated, and the effect on organic fractionations in coagulated water was determined. The study results could provide useful implications in designing DWTS recycling processes that avoid the enrichment of organic matter. Our results indicate that DWTS was disrupted through a low release of soluble chemical oxygen demand (SCOD) and proteins, which could deteriorate the coagulated water quality under the specific energy of 37.87-1212.1 kW h/kg TS. The optimal coagulation behavior for NOM removal was achieved by recycling the sonicated DWTS without solubilized organics at 151.5 kW h/kg TS specific energy. Recycling the sonicated DWTS could increase the enrichment potential of weakly hydrophobic acid, hydrophilic matter, and <3 kDa fractions; the enrichment risks could be reduced by discharging the solubilized organics. Fluorescent characteristic analysis indicated that when recycling the sonicated DWTS without solubilized organics, the removal of humic-like substances was limited, whereas removal of protein-like substances was enhanced, lowering the enrichment potential of protein-like substances. [ABSTRACT FROM AUTHOR]