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The absorption of high-viscosity oil by traditional oil absorbing materials has always been a challenge. So there is an urgent need to solve the problem of slow absorption of high-viscosity oil. In this work, an emulsion composed of polydimethylsiloxane (PDMS), carbon black (CB) and waterborne polyurethane (solid content 40%) was sprayed on the melamine foam (MF). After volatilization of organic solvents, the photothermal material CB was fixed on the MF framework, making it photothermal. By raising the temperature of the modified foam to accelerate the internal thermal movement of high-viscosity oil molecules around the foam, intermolecular forces are reduced, thereby accelerating the separation process. The absorption capacity of this modified MF towards organic solvents and oil is up to 79 times its own weight. In addition, the mechanical properties of the modified foam are improved to a certain extent, more conducive to the continuous oil–water separation. This photothermal absorption material provides ideas for the rapid removal of high-viscosity oil, heavy oil, etc. [ABSTRACT FROM AUTHOR]

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Background and aims: Biological invasions have tremendous effects on soil biodiversity. Although the effects of invasive plants on soil biota have been widely investigated, how soil fauna invasion affects native soil biodiversity in island ecosystems remains unclear. Methods: Field survey in non-invaded and invaded sites was conducted to investigate the effects of the giant African snail invasion on native soil biodiversity on tropical coral islands. Results: The effects of snail invasion on native soil biodiversity were strongly dependent on sampling seasons. Fungal biomass, microbial diversity, and nematode abundance (except omnivores/predators) increased by snail invasion in the dry season but decreased in the wet season. Mite abundance and diversity increased, whereas the activities of β-1,4-glucosidase, β-D-cellobiosidase, β-N-acetyl-glucosaminidase, and alkaline phosphatase decreased by snail invasion in both dry and wet seasons. Snail invasion homogenized the seasonal community composition of nematodes, the fungi: bacteria ratio (F: B ratio), and the Gram-positive: Gram-negative bacteria ratio (GP: GN ratio). These results together indicate that snail invasion does not have greater effects on soil biota at lower trophic levels but also has great effects on those at higher trophic levels. Soil moisture, soil organic carbon, available phosphorus, and potassium were important factors explaining the variation of soil biodiversity under snail invasion. Conclusion: These results together indicate that alien snail invasion weakens the seasonal variation of native soil biodiversity by altering soil resource availability. Such information is valuable for improving our understanding of the ecological consequences of alien organism invasion on soil biodiversity in tropical coral islands. [ABSTRACT FROM AUTHOR]

This study explores the application of oriented strand board (OSB) to hybrid cross-laminated timber (HCLT). OSB and larch were used to fabricate hybrid forms of HCLT for analysis. Firstly, the impact of surface treatment on OSB was investigated in terms of its influence on the bonding line between materials, encompassing both pre-treatment and post-treatment surface properties of OSB. The findings indicate that sanding has the ability to alter the surface properties of OSB, leading to an increase in surface roughness and surface free energy, and reduce the pre-cured layer. Notably, there is no significant disparity observed in both the shear failure mode and shear strength of the bonding line of CLT, and the failure is in the core layer of OSB. Secondly, two layups of HCLT were prepared by combining OSB with larch. The interlaminar shear strength was assessed in both the major and minor strength directions using a three-point bending test. The results showed that, due to the low density and mechanical properties of the core layer of OSB, its application in HCLT as perpendicular layer is not a favorable choice, because it cannot prevent the rolling shear failure in perpendicular layer, and it also diminishes the interlaminar shear strength of HCLT in the minor strength direction. However, the interlaminar shear strength increases in the minor strength direction when OSB was used as the parallel layer, and larch was used as the perpendicular layer, even stronger than that in major strength direction. [ABSTRACT FROM AUTHOR]

In this study, the pore structure of carboxymethyl chitosan aerogel (CCSA) was modulated by adjusting the concentration of carboxymethyl chitosan (CCS) in combination with targeted freezing. The hierarchically porous structures were obtained by the freeze-drying process. The results show that the CCSAs prepared by directional freezing have excellent broadband acoustic absorption properties, and also expand the scope of application of CCSAs in practical applications due to the excellent thermal and mechanical properties of the prepared CCSAs. Since the CCSAs prepared by directional freezing still has excellent antimicrobial properties, it also provides a new strategy for aerogels with acoustic properties to be used in medical industry applications. [ABSTRACT FROM AUTHOR]

We explored the gravity dual of a rotating quark-gluon plasma by transforming the boundary coordinates of the large black hole limit of Schwarchild-AdS5 metric. The Euler-Lagrange equation of the Nambu-Goto action and its solution become more complex than those without rotation. For small angular velocity, we obtained an analytical form of the drag force acting on a quark moving in the direction of the rotation axis and found it stronger than that without rotation. We also calculated the heavy quark potential under the same approximation. For the quarkonium symmetric with respect to the rotation axis, the depth of the potential is reduced by the rotation. For the quarkonium oriented in parallel to the rotation axis, the binding force is weakened and the force range becomes longer. We also compared our holographic formulation with others in the literature. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to understand the above- and belowground community assembly in subtropical plantations, and to detect the relationship with understory plant communities, soil microbial communities and stocks of soil organic carbon, nitrogen and phosphorus. Methods: We compared the composition and diversity of understory plants and microbial communities among exotic monocultures versus native conifer and broadleaved mixtures, and tested the co-structure between understory plant communities, soil microbial communities and soil characteristics. Results: The two native mixtures compared to exotic monocultures had greater understory plant cover (except for the herbaceous cover that was lower) and diversity, but lower community weighted mean of shrub and herbaceous leaf carbon content. Exotic monocultures and native broadleaved mixtures had a higher biomass of each microbial group than native conifer mixtures based on phospholipid fatty acids (PLFAs) extractions. Based on high throughput sequencing, we found higher bacterial and fungal richness in native mixtures than in exotic monocultures, but lower bacterial Shannon diversity. In terms of soil nutrients, only the soil phosphorus stocks were significantly higher in native mixtures than in exotic monocultures. Moreover, in the two native mixtures there was a strong co-structure between understory plants, soil microbes and soil nutrients. Yet, fungal phyla did not have any co-structure with other taxa. Conclusion: Our study highlights the important yet inconsistent roles of different plantation types in affecting the patterns of above- and belowground diversity, soil nutrients, and the maintenance of their relationships. Long-term monitoring is suggested to determine whether the main findings change with plantation restoration over time. [ABSTRACT FROM AUTHOR]

In this work, a robust trajectory tracking control strategy is developed for the quadrotor unmanned aerial vehicle (QUAV) with unknown external disturbance. The nonlinear dynamic model of QUAV is established. Different from the traditional disturbance observer and adaptive estimation method, this paper adopts the interval observer technique to approximate the upper and lower bounds of the unknown disturbance. In this way, the proposed interval observer can cover its all possible values and show its scope in real time, especially before the disturbance error estimation converges. Combining with the backstepping approach, a robust tracking control approach is proposed to ensure that the desired trajectory can be successfully followed. Finally, comparative numerical simulation results are provided to evaluate the presented robust tracking controller. [ABSTRACT FROM AUTHOR]

Reasonable construction of high activity and low cost non-noble metal oxygen reduction reaction (ORR) catalyst is of great importance for the wide application of zinc-air batteries (ZABs). Using bimetallic MOF as a precursor combined with electrospinning, high-temperature carbonization and electrodeposition, we successfully developed a porous carbon nanofiber (Co@Fe-CNFs-1000) with bimetallic active center as an efficient catalyst for ORR. The successful construction of this special core-shell structure directly explores the synergy between different active centers. The results showed that the synthesized Co@Fe-CNFs-1000 catalyst exhibited ORR performance comparable to that of Pt/C in 0.1 mol/L KOH electrolyte, high half-wave potential (E1/2=0.81 V) and limiting current density (JL=5.4 mA-cm−2). In addition, homemade liquid ZABs with Co@Fe-CNFs-1000 as the air cathode showed excellent power density (155.8 mW·cm−2), specific capacity (780.6 mAh·gZn−1) and long-term stability (over 100 h at 2 mA·cm−2), surpassing even Pt/C-based batteries. In addition, the flexible solid-state ZABs assembled based on Co@Fe-CNFs-1000 demonstrates excellent flexibility and durability. This work provides a new idea for constructing ORR catalysts with high activity centers. [ABSTRACT FROM AUTHOR]

Photodynamic antibacterial composite membranes were engineered by integrating photosensitizer/antibacterial agent, into the polyurethane adhesive blend and coating the blend on co-electrospinning cellulose acetate(CA)/thermoplastic polyurethanes(TPU) composite membrane support for enhanced antibacterial performance. The central composite design (CCD) method based on the response surface method (RSM) was used for analysis to illustrate the influence of important variables. The optimized parameters of CCD were TPU (wt%) 22.64%, CA (wt%) 18.63, DMAC/acetone volume ratio 0.85, LiCl (wt%) 0.95%, voltage (kV) 23.33 kV. Fiber diameter was the key response process output variable. The membranes were characterized by SEM, XPS, and molecular structure analyses. The model had excellent applicability as a tool to realize the average diameter of the CA/TPU bicomponent electrospun membrane. Results showed that after coating, the synergistic effects of photodynamic antibacterial and antibacterial agent performance on the Antibacterial composite membrane were achieved under ordinary daylight irradiation. The sterilization rate of S. aureus and E. coli could achieve excellence at 99.2% and 93.4%, respectively. This method of preparing photodynamic antibacterial composite film provides a new direction for the design of medical antibacterial protective materials. [ABSTRACT FROM AUTHOR]

The application of DNA barcoding has been significantly limited by the scarcity of reliable specimens and inadequate coverage and replication across all species. The deficiency of DNA barcode reference coverage is particularly striking for highly biodiverse subtropical and tropical regions. In this study, we present a comprehensive barcode library for woody plants in tropical and subtropical China. Our dataset includes a standard barcode library comprising the four most widely used barcodes (rbcL, matK, ITS, and ITS2) for 2,520 species from 4,654 samples across 49 orders, 144 families, and 693 genera, along with 79 samples identified at the genus level. This dataset also provides a super-barcode library consisting of 1,239 samples from 1,139 species, 411 genera, 113 families, and 40 orders. This newly developed library will serve as a valuable resource for DNA barcoding research in tropical and subtropical China and bordering countries, enable more accurate species identification, and contribute to the conservation and management of tropical and subtropical forests. [ABSTRACT FROM AUTHOR]

In this study, the electronic structure and mechanical and magnetic properties of quaternary Heusler alloy FeMnZnZ (Z = Si, Ge, Sn, Pb) were analyzed through first-principles calculations. The electronic band and density of the state of FeMnZnSi and FeMnZnGe indicated that they are half-metallic with an indirect and direct band gap of 0.329 and 0.342 eV, respectively. The magnetic moments derived from magnetic calculations suggested that both alloys satisfied the Slater–Pauling rule of M t = Z t - 28 with a total magnetic moment of 3 µB. Moreover, the effects of the uniform strain of the lattice constant on the half-metallicity of alloys were analyzed. The lattice constants of FeMnZnSi and FeMnZnGe exhibited half-metallic properties ranging from − 5 to 21% and − 13 to 14%, respectively. Furthermore, after using Si as the lattice constant, FeMnZnZ (Z = Sn, Pb) exhibited a magnetic moment of 3 µB, which satisfied the Slater–Pauling rule of M t = Z t - 28 , and demonstrated half-metallic properties. Finally, the relationship between the changes in the total magnetic moment, atomic magnetic moment, half-metallic band gap, and lattice constant of this series of half-metallic alloys was examined. [ABSTRACT FROM AUTHOR]

The regenerated cellulose membrane (RC) was synthesized by dissolving cotton cellulose in NaOH/CO(NH2)2 system. The Polydopamine/Bismuth tungstate/RC composite membrane (RCPB) with photocatalytic activity was synthesized by loading polydopamine-modified bismuth tungstate (PDA/BWO) composite onto the RC by blending method. The RCPB/PAN/RCPB sandwich structure membrane was synthesized by combining the polyacrylonitrile (PAN) nanofiber membrane and RCPB by scraping method, which can reduce aqueous Cr(VI) under visible light effectively. Characterization shows that the tensile strength, elongation at break, roughness and initial water contact angle of RCPB/PAN/RCPB are 32.1 MPa, 5.34%, 0.658 μm and 69.0°, respectively. The photoreduction percent of Cr(VI) by RCPB/PAN/RCPB can reach 99.7% within 120 min with a rate constant of 0.0869 min−1, and the photoreduction percent remains above 84.6% after four cycles. The introduction of PAN nanofiber membrane further improves the mechanical properties and recycling ability of RCPB. Meanwhile, the capture experiments reveal that the main active substance for photocatalytic reduction of Cr(VI) by RCPB/PAN/RCPB is photogenerated e−. This work provides a new idea for the treatment of Cr(VI)-containing wastewater. [ABSTRACT FROM AUTHOR]

In this study, a hydrogel adsorbent was successfully synthesized using hydroxyapatite/acrylamide/β-cyclodextrin to adsorb heavy metal ions and dyes in water. In the study, different contents of hydroxyapatite were added to the hydrogel, and the mechanical properties and adsorption properties of the material were studied. Results showed that the compressive strength of the hydrogel added with hydroxyapatite increased by 37.1%. The adsorption isotherm model demonstrated that the maximum adsorption capacity was 300 mg/g. In addition, the preparation process of the composite hydrogel was simple and could be used at a low pH for multiple times. Therefore, the material is of great significance to the treatment of pollutants. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) is a reversible treatment for chorea-acanthocytosis (ChAc). Its safety and efficacy remain elusive due to the low prevalence of ChAc. We aimed to investigate the safety and efficacy of DBS for ChAc by systematically reviewing literature through PubMed and EMBASE. Inclusion criteria were reports on the efficacy or safety of DBS for ChAc and English language articles, and exclusion criteria were other movement disorders, non-human subjects, and studies without original data. Most studies were published as case reports, and we therefore pooled these cases in one cohort. Twenty studies with 34 patients were included. The mean age of symptom onset was 29.3 years (range, 17–48). The median follow-up was 12 months (range, 2–84). Twenty-nine patients underwent GPi-DBS, two received STN-DBS, and one underwent Vop-DBS. Electrodes were implanted into the ventralis oralis complex of the thalamus and the pallidal in two patients. Symptoms seemed to be easier relieved in chorea (88.5%) and dystonia (76.9%) but dysarthria of most patients (85.7%) was no response after DBS. The Unified Huntington's Disease Rating Scale-Motor Score was used to assess the efficacy of DBS in 25 patients; the mean score decreased from 43.2 to 22.3 and the median improvement rate was 46.7%. Of 24 patients with data on adverse events, complications occurred in 9 patients (37.5%; mostly transient and mild events). DBS is a promising treatment for ChAc with satisfactory efficacy and safety based on the review. Pallidal and thalamic DBS have been applied in ChAc; GPi-DBS seems to be more widely used. [ABSTRACT FROM AUTHOR]

In this work, a Carrier Waveform Inter-Displacement (CWID) modulation, based on Linear Frequency Modulation-Phase Shift Keying (LFM-PSK), is proposed to achieve high Bit Transmission Rate (BTR) in wireless radio communications system. The novel modulation scheme introduces position modulation by re-ordering inter-displacement in different symbol carriers, which improves the BTR as compared with the LFM-PSK system. Moreover, a Graphical User Interface (GUI) based on Wireless open-Access Research Platform (WARP) is designed and the CWID system is implemented and validated on the Software Defined Electronics platform. Results of simulations and experiments show the effectiveness and the superiority of the CWID over its competitors. [ABSTRACT FROM AUTHOR]

This study explored the impact of low luteinizing hormone (LH) levels during ovarian stimulation on endometrial function. Based on previous studies by us and others, we divided the patients into low (< 4 IU/L), medium (4–10 IU/L), and high (> 10 IU/L) LH groups. The study utilized a comparison control group design with three groups of 10 patients. Gene set enrichment analysis (GSEA) was applied for functional annotation. By analyzing the exon differentially expressed genes in the endometrium of these three patient groups during the embryo implantation window, we found that when compared to the medium LH group, low LH downregulated endometrial cell metabolism, including mitochondrial-nicotinamide adenine dinucleotide (Normalized Enrichment Scores, NES = − 1.53) and glycolytic metabolism (NES = − 1.22), immune regulation, and autophagy (NES = − 1.58). Transcription factors were the main regulators of cell function. We found that MCM2 was probably involved in regulating the endometrial function induced by low LH. MCM2 target genes were enriched in low LH group, NES = − 1.54. Low LH, but not high LH, altered the endometrial receptivity assay gene expression in comparison to the medium LH. Our results indicated that low LH impacted the endometrial cell function, with a greater effect than high LH. This research provides timely and necessary data on the involvement of LH in important endometrial cellular processes and these data support further clinical development of endometrial receptivity. [ABSTRACT FROM AUTHOR]

Chaos occurs in the flexible shaft rotating-lifting (FSRL) system of crystal growth process. Chaotic swing does harm to the quality of mono-silicon crystal production. Therefore, it must be suppressed. Previous studies have proposed impulse control method to suppress the chaos in crystal growth process. However, the impulses require sudden and intermittent changes to the rotation speed, which are difficult to implement through the soft rope connection. In this work, a small amplitude resonant perturbation to the rotation speed is being proposed to suppress chaos in the FSRL system. The system state, given by the swing angle between the rotation center on the vertical axis and the soft shaft, is observed by measuring the force on the soft shaft and by using the untraced Kalman filter. The control parameters are selected by calculating the Lyapunov exponent. As compared with the previous impulse control methods, the proposed small amplitude resonant perturbation method engenders a small continuous change instead of the sudden change in the rotation speed. In addition, the proposed method does not alter the average rotation speed, which complies with the crystal growth technique requirement. The effectiveness of the proposed chaos control method is validated by numerical simulations. [ABSTRACT FROM AUTHOR]

Metalloproteases represent a class of extracellular proteases found in Vibrio anguillarum that can generate toxic and pathogenic effects in turbot (Scophthalmus maximus). The toxicological effect partly results from oxidative damage due to the production of excessive reactive oxygen species (ROS). Catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) are major antioxidant enzymes induced by various oxidative stresses and can scavenge peroxides generated in cells. To evaluate the effects of metalloprotease-induced ROS on the antioxidation defense mechanism of S. maximus head kidney cells, the cDNA of CAT gene (designated as SmCAT) was cloned and characterized. SmCAT comprises a 1 584-bp coding sequence that encodes a protein containing 527 amino acids with a poly(A) tail. Bioinformatics analysis revealed an active site signature sequence, a heme-ligand signature sequence, and three catalytic amino acid residues. The deduced SmCAT amino acid sequence shares a sequence similarity of 66.1%–92.4% with those of other species. Phylogenetic analysis revealed that SmCAT is classified with CAT of other fishes. Quantitative real-time PCR analysis showed that SmCAT was extensively expressed in all tested tissues, especially in blood. The expression of SmCAT, SmMnSOD, and SmGPx were inhibited significantly in head kidney cells treated with metalloprotease from 12 to 24 h. In 6 to 24 h metalloprotease-treated groups compared to that of the untreated group, it was found that the production of ROS was markedly increased, and the mitochondrial membrane potential was decreased considerably. Hoechst 33342 staining revealed the presence of apoptotic bodies when the cells were incubated with 8.0 or 40.0 μg/mL metalloprotease for 12 and 24 h. Hence, the toxic effects of metalloprotease are associated with the down-regulation of antioxidant enzyme expression and increased ROS levels, which trigger the activation of apoptosis in the head kidney cells of turbot. Our findings provide a better understanding on the mechanism of metalloprotease-induced apoptosis in fish. [ABSTRACT FROM AUTHOR]

Lepturus repens (G. Forst.) R. Br. is a perennial grass that grows on coral reef outcrops and sandy beaches and has drought tolerance and salt resistance. In this study, the internodes of L. repens were used as explants and cultured on Murashige and Skoog (MS) medium supplemented with 1.13 mg L−1 6-benzyladenine (BA) to successfully induce axillary shoots. Additional experimental results showed that cytokinins were a key factor for the successful induction and proliferation of shoots. BA induced 7.2 axillary shoots per explant, significantly more than kinetin (KIN), which induced 3.5 axillary shoots per explant. Shoots were proliferated more successfully on medium supplemented with 1.13 mg L−1 BA and a low concentration of 0.09 mg L−1 1-naphthaleneacetic acid (NAA) than BA alone. Shoot bases were used as explants for embryogenic callus induction and subsequent plant regeneration, which was possible on MS medium supplemented with 0.11 mg L−1 2,4-D, 0.09 mg L−1 NAA, and 0.22 mg L−1 TDZ. Separately, callus differentiated into adventitious shoot buds on MS medium containing 1.13 mg L−1 BA or 1.10 mg L−1 KIN singly or combined with 0.09 mg L−1 NAA. On MS medium without plant growth regulators (PGR-free) or only containing 0.09 mg L−1 NAA, callus induced both adventitious shoots and somatic embryos that developed a radical on PGR-free medium. All shoots formed roots on ½MS medium containing a low concentration (0.19 to 0.37 mg L−1) of NAA or IBA within 20 d. The survival percentage of plantlets with 3 to 4 shoot clusters exceeded 99% on a substrate consisting of yellow mud, organic fertilizer, and perlite (10:3:1, v:v:v). After transplanting, plantlets with one or two shoot clusters showed 68 to 86% survival within 1 mo. [ABSTRACT FROM AUTHOR]

Twenty-year-old Pinus radiata trees imported from New Zealand were investigated, and a comparison was made between the outerwood (rings 16–20) and corewood (rings 4–6) in terms of mechanical properties, anatomical characteristics, microfibril angle (MFA), relative crystallinity, crystallite size and lignin content to determine the relationship between their mechanical properties and microstructures. The results demonstrated that the mechanical properties of the Pinus radiata outerwood were significantly better than those of the corewood. The outerwood had a modulus of rupture (MOR) of 106 MPa, a modulus of elasticity (MOE) of 11.4 GPa, and compressive strength parallel to the grain of 38.7 MPa, and the MOR, MOE and compressive strength parallel to the grain of the corewood were 78.9 MPa, 7.12 GPa and 29.3 MPa, respectively. The observed microstructures of the Pinus radiata outerwood and corewood were different, mainly due to differences in cell wall thickness, MFA, and relative crystallinity. The double wall thickness of the tracheid cells of the corewood and outerwood were 3.65 and 5.02 µm, respectively. The MFA data indicated that the average MFA of the outerwood was 14.0°, which was smaller than that of the corewood (22.3°). With X-ray diffraction, the relative crystallinity of the corewood was determined to be 35.7%, while that of the outerwood was 40.2%. However, the crystallite size of the outerwood cell wall shows no obvious difference from that of the corewood. Imaging FTIR spectroscopy showed a slightly higher relative content of lignin in the cell wall of the outerwood. The correlation between the microstructures and mechanical properties showed that the corewood with a thin cell wall, large MFA and low relative crystallinity had poor mechanical properties, while the outerwood with a thicker tracheid, smaller MFA and higher relative crystallinity had better mechanical properties. This means that the MFA, relative crystallinity and cell wall thickness synergically affect the mechanical properties of Pinus radiata in different radial locations. [ABSTRACT FROM AUTHOR]

Pathogenic bacteria of Scophthalmus maximus enteritis were isolated from and identified in an aquaculture farm in Changli County, Hebei Province, China. The feasibility of rapid selection of prevention and treatment drugs via PCR technology was investigated through drug resistance phenotype analysis and drug resistance gene detection. A dominant bacterial strain was isolated from S. maximus and designated HC-1. Morphological observations, culture property investigations, and physiological-biochemical experiments were conducted, which showed that the strain was consistent with the phenotypic characteristics of Vibrio. Based on 16S rRNA sequence determination and homology analysis, HC-1 was determined to be 99.65% similar to Vibrio harveyi NR 043165.1. Therefore, the bacterium was identified as V. harveyi. The sensitivity of the V. harveyi isolate to 41 antibiotics was determined by the Kirby-Bauer method. The results showed that HC-1 was resistant to 8 agents, namely, penicillin, oxacillin, amoxicillin, ampicillin, spectinomycin, azithromycin, florfenicol, and carbenicillin. The antimicrobial resistance gene analysis results showed that tem, ant(3˝)-I and tetA are carried by the chromosome of the strain and the plasmid, while sul1 is carried by the chromosome of the strain but not the plasmid. In contrast, floR is carried only by the plasmid but not by the chromosome. vanA, qnrA, and mefA are not carried by the plasmid or chromosome of the strain. Although the resistant phenotype of the strains is regulated by resistance genes, the relationship between the phenotype and genotype should be revealed by numerous databases. To accelerate the speed of treatment selection, it is necessary to apply PCR technology to detect resistance genes to replace drug sensitivity testing. These results provide useful information for further understanding the antimicrobial resistance factors and treatment of bacterial disease in S. maximus. [ABSTRACT FROM AUTHOR]

The chiral magnetic effect with a fluctuating chiral imbalance is more realistic in the evolution of quark-gluon plasma, which reflects the random gluonic topological transition. Incorporating this dynamics, we calculate the chiral magnetic current in response to space-time dependent axial gauge potential and magnetic field in AdS/CFT correspondence. In contrast to conventional treatment of constant axial chemical potential, the response function here is the AVV three-point function of the N = 4 super Yang-Mills at strong coupling. Through an iterative solution of the nonlinear equations of motion in Schwarzschild-AdS5 background, we are able to express the AVV function in terms of two Heun functions and prove its UV/IR finiteness, as expected for N = 4 super Yang-Mills theory. We found that the dependence of the chiral magnetic current on a non-constant chiral imbalance is non-local, different from hydrodynamic approximation, and demonstrates the subtlety of the infrared limit discovered in field theoretic approach. We expect our results enrich the understanding of the phenomenology of the chiral magnetic effect in the context of relativistic heavy ion collisions. [ABSTRACT FROM AUTHOR]

Objective: A peripherally inserted central catheter (PICC) needs regular care. However, clinical observations found that some discharged leukemia patients in mainland China had not complied with the requirement of regular care. Our study aims to explore the facilitators and hindrances of regular cares of PICC in leukemia patients with the Colaizzi phenomenon analysis. Methods: This qualitative report used the descriptive phenomenological method to collect information and was conducted in accordance with the COREQ checklist. By purposive sampling, 11 leukemia patients with PICC were selected and interviewed in the Department of Hematology of a first-class hospital in Wuhan (central China). The interviews were conducted from March 2016 to May 2017. Results: Two facilitators for PICC care were extracted through interviews, including fear of nosocomial infection and convenience for treatment. Eleven hindrances were summarized, including high costs, unavailability of local services, worries about affecting family members, a lack of health awareness, inconvenient transportations, fluke minds, physical discomfort, fears of leukemia and chemotherapy, short chemotherapy intervals, damage to appearance, and no insurance coverage of costs. Conclusion: Leukemia patients' compliance with PICC care was hindered by several factors. The improvement of PICC care may need joint efforts of patients, nursing professionals, hospitals' managerial staff, and governments. [ABSTRACT FROM AUTHOR]

The mining-induced stress distribution and fracture characteristics of overlying strata in the lower coal seams are different from those in single coal seam mining. Based on the distribution of the mining-induced fracture elliptical parabolic zone in a single coal seam, the dynamic distribution equation is deduced for the mining-induced fracture elliptical parabolic zone in two short coal seams through theoretical analysis. Combined with physical experiment and numerical simulation, a study has been made on the characteristics of overlying strata deformation, displacement, and mining-induced fracture evolution in the single coal seam and its lower coal seam mining. The results show that high stress concentrations occurred near the coal pillars at the upper coal floor on both sides after mining, and the overlying strata subsidence of the upper coal seam is 155.70% of the intermediate strata after superimposed mining, with the upper and lower coal floor showing significant stress relief. Under the influence of the two mining actions, the overlying strata of the upper coal seam have more fully developed fractures. The fracture density increases with the advance distance, the position of caving zone and fracture zone continues to develop upward, and the compaction zone further compacts; the fracture zone presents the distribution of the superimposed mining elliptical paraboloid zone. FLAC3D was used to simulate superposition of two layers of coal mining; the strata displacement and stress distribution nephograms were obtained as well, with the result that the floor stress release could reach up to 14.87 MPa under the influence of mining of two adjacent seams. This indicates that the pressure relief degree of the floor under the influence of two mining operations is obviously higher than that under one mining operation. The fracture distribution obtained by numerical simulation is basically consistent with the physical simulation and the superimposed mining elliptical paraboloid zone. [ABSTRACT FROM AUTHOR]

The use of regular wound dressings commonly brings about excessively retained wound exudate between the dressing and the wound, which is detrimental to the healing. This study manages to control the biofluid around wounds effectively. To begin with, silk fibroin (SF) is extracted from silk. Next, SF and PCL are mixed and electrospun into multiscale hydrophobic nanofibers on the surface of the dopamine (PDA)-treated hydrophilic PVA nanofibrous membranes, thereby forming asymmetric wetability composite membranes with one-way water conduction. Moreover, PVA nanofibrous membranes are immersed in a PDA solution with an attempt to have a greater surface chemical activity and thus demonstrate an 85% greater wicking height and an air permeability being 90 mm/s. A 20% (w/v) SF solution and an 8% (w/v) PCL solution with a feeding rate being 1:3 provide the resulting SF/PCL nanofibrous membranes with greater hydrophobic properties, namely a water contact angle being 112°. In addition, the ultimate asymmetric wetability composite membranes exhibit an excellent wetting gradient, which benefits the directional transmission of moisture. The moisture management test results indicate that when the electrospinning time for PVA and SF/PCL layers is separately 30 min and 5 min, the resulting composite membranes attain the effect of one-way water conduction. In vitro analysis confirmed that the composite membrane produced were non-toxic. This unique wound dressing with one-way water conduction has a giant potential to serve as new type wound dressings for clinical use. [ABSTRACT FROM AUTHOR]

Subtropical China has a large area of Acacia mangium plantations; however, some key aspects of the structural and functional changes and the associated mechanisms after planting are still not well understood. We established a permanent plot in an A. mangium plantation and monitored the plant diversity (i.e., the number of species), biomass, soil physical and chemical properties and light transmittance from 1984 to 2018. Protocols for standard observation and measurement of Chinese Ecological Research Network were adopted. The total number of species in the plantation increased gradually from 3 to 38 during the 34-year period. The biomass in the tree layer initially increased rapidly from 1.60 to 185.01 t/ha within 7 years and then slowly increased to 188.69 t/ha during the following 27 years. The soil fertility of the A. mangium plantation improved continuously over the 34-year period. Vegetation restoration had positive effects on soil properties, such as soil moisture, soil bulk density, soil organic matter and soil total nitrogen and available phosphorus contents. The structure (i.e., plant diversity and light transmittance) and function (i.e., biomass and soil fertility) of the A. mangium plantation were not restored synchronously after 34 years of development. However, considering that the tree species richness in the natural forests in this region was 134, this plantation has slowly transformed from plantation to a natural forest. Artificial intercropping with native tree species can facilitate succession to a natural forest. [ABSTRACT FROM AUTHOR]

Medical product contamination is a serious threat to patients' health. However, designing medical covers that ensure Janus performance and outstanding abrasion resistance, mechanical performances has remained a great challenge. In this study, a novel Janus nonwoven fabric nonwoven fabric consists of a hydrophilic inner layer of polylactic acid (PLA)/lowmelting polylactic acid (LPLA) and a coated outer layer of hydrophobic thermoplastic polyurethane (TPU) is successfully fabricated. The subsequent PLA/LPLA-TPU textiles exhibits excellent protective performance of inner absorption. Moreover, the coating improves tensile strength and increases abrasion resistance. A mechanism of mechanical failure is further studied. This kind of nonwoven fabric is suggested to be a promising candidate for medical covers and health supplies. [ABSTRACT FROM AUTHOR]

Silicon crystal puller (SCP) is key equipment in silicon wafer manufacture, which is, in turn, the base material for the most currently used integrated circuit chips. With the development of the techniques, the demand for longer mono-silicon crystal rod with larger diameter is continuously increasing in order to reduce the manufacture time and the price of the wafer. This demand calls for larger SCP with an increasing height, though it causes serious swing phenomenon of the crystal seed. The strong swing of the seed increases the possibility of defects in the mono-silicon rod and the risk of mono-silicon growth failure. The main aim of this paper is to analyze the nonlinear dynamics in flexible shaft rotating–lifting (FSRL) system of the SCP. A mathematical model for the swing motion of the FSRL system is derived. The influence of relevant parameters, such as system damping, excitation amplitude, and rotation speed, on the stability and the responses of the system is analyzed. The stability of the equilibrium, bifurcation, and chaotic motion is demonstrated, which have been observed in practical situations. Melnikov method is used to derive the possible parameter region which leads to chaotic motion. Three routes to chaos are identified in the FSRL system, including period doubling, symmetry-breaking bifurcation, and crisis. The work in this paper analyzes and explains the complex dynamics in FSRL system of the SCP, which will be helpful for the designers in the designing process in order to avoid the swing phenomenon in the SCP. [ABSTRACT FROM AUTHOR]

Visible light response PAN@Ag–Ag2O/TiO2 (PAN@AT) nanofibers with different mass ratios between Ag–Ag2O and TiO2 were synthesized via a facile electrospinning technique and pH-induced precipitation reaction. X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscope analyses manifest the formation of Ag–Ag2O/TiO2 heterojunctions, and Ag–Ag2O/TiO2 nanoparticles are evenly distributed on PAN nanofibers. The fabricated nanofibers show a highly photocatalytic performance toward As(III) oxidation under visible light, and the conversion is 92.1% after 120-min reaction at pH 5.0 in the system of PAN@AT4. Furthermore, conversion of As(III) can retain 88.6% of the original activity after repeating four cycles, indicating the good recyclability of PAN@AT4 nanofibers. Quenching experiments and electron spin resonance spectra analysis further demonstrate that the predominate active species for As(III) oxidation by PAN@AT4 are h+ and ·OH. The enhanced catalytic activity of PAN@AT4 is therefore ascribed to the formation of Ag–Ag2O/TiO2 heterojunctions on PAN surface and the efficient separation of photoinduced electron–hole pairs. This study provides a new material to oxidize reducing pollutants [such as As(III)] and also sheds light on the fabrication of recyclable photocatalysts. [ABSTRACT FROM AUTHOR]

An efficient regeneration system via shoot organogenesis and somatic embryogenesis from in vitro leaf and root explants was established for Scaevola sericea for the first time. The highest axillary shoot proliferation coefficient (4.8) was obtained on Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 6-benzyladenine (BA) and 0.1 mg/L α-naphthaleneacetic acid (NAA) every 45 days. Young in vitro leaves and roots, which were used as explants, were cultured onto medium supplemented with different plant growth regulators. Our results showed that only cytokinins BA and thidiazuron (TDZ), could induce adventitious shoots and somatic embryos from leaf and root explants. The optimal medium to achieve this was MS medium supplemented with 2.5 mg/L BA and which induced most adventitious shoots (2.7) and somatic embryos (17.3) from leaf explants within 30 days. From root explants, 1.1 adventitious shoots and 7.6 somatic embryos could be induced on MS medium supplemented with 2.5 mg/L TDZ. Histological observation showed that both somatic embryos and adventitious shoots were originated from homogeneous parenchyma and the development of somatic embryos was visible. Maximum rooting percentage (99.0%) was achieved on half-strength MS medium supplemented with 2.5 mg/L NAA. Well-rooted plantlets, which were transplanted into a substrate of pure river sand, displayed a high survival percentage of 91.7% after transplanting for 45 days while the best substrate for plantlet growth was river sand: coral sand (1:1). [ABSTRACT FROM AUTHOR]

In this study, electrospun polyvinylidene fluoride (PVDF)-based nanofibrous membranes embedding TiO2 were prepared and used for photocatalytic degradation and oil/water separation. The nanofibrous membranes were characterized by scanning electron microscopy (SEM), transmission electronic microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) spectroscopy, thermal performance analysis, and oil/water separation analysis. And the degradation of rhodamine B dye was also investigated. Results showed that the fiber diameter and thermal stability of the membranes decreased with the increasing of TiO2. Meanwhile, the fiber surface roughness and specific surface area increased. The analysis of TEM, XRD and FTIR indicated that TiO2 existed in the PVDF membranes. When the TiO2 content was 12 %, the fiber diameter of the membranes was about 110 nm, and the photocatalytic degradation of rhodamine B dye efficiency was up to 97 %. The reaction rate constant was 0.02057 min−1. At 0.01 MPa vacuum, oil separated from water effectively, which proves that separation can be easily conducted with a low energy cost. Thus, the prepared membranes have a very high application prospect in the purification of reclaimed water and separation of oil and water. [ABSTRACT FROM AUTHOR]

Bio-ceramic hydroxyapatite (HA) coating has been commonly used to repair the bones or as the functionalized surface of bone substitutes due to its excellent biocompatibility, superior osteo-inductivity, and great corrosion resistance. Among many other methods for synthesizing HA coating, coating via the electrochemical deposition has a high degree of crystallinity and purity, which fits the nonlinear, complex, and rugged substrates. Furthermore, HA coating can be adjusted in terms of coating morphology, thickness, and chemical component via changing the parameters, such as electrolyte ion concentration, electrolyte composition, deposition current density, and deposition time, etc. Nevertheless, the properties of electrodeposited HA coating highly pertain to the bubbles generated by water electrolysis on the substrate surface as well as the concentration polarization of electrolyte ions near the cathode during the electrodeposition process. In this study, the critical factors and mechanisms of HA coating using the electrochemical deposition method are comprehensively evaluated, thereby examining the effects of parameter optimization (i.e., current mode, ultrasonic treatment, and postprocessing). Finally, the influences of ion substitution and HA composite coating on the surface structure and properties of the HA-based coatings are also discussed. [ABSTRACT FROM AUTHOR]

Linear time-delay feedback method makes the stable system generate the infinite-dimensional hyper-chaos, which possesses more than one positive Lyapunov exponent, infinite-dimensional, a wider chaotic parameter range, and multi-attractors, including the single-scroll attractor, the double-scroll attractor, and the composite multi-scroll attractor. The infinite-dimensional hyper-chaotic multi-attractors Chen system generated by linear time-delay feedback (HCMACS) is used for image encryption. Firstly, the state time sequences of the infinite-dimensional HCMACS are preprocessed to achieve the ideal statistical property. Secondly, two random matrices generated by random number generators are used to expand the image size. Finally, the preprocessed chaotic sequences are used to confuse and diffuse the expanded digital image to obtain the encrypted image. The special feature of the proposed method is the theoretically infinite-dimensional secret key space. Results of analysis and computer simulation indicate that the encryption algorithm has good encryption performance, which can effectively resist various attacks. [ABSTRACT FROM AUTHOR]

This study established, for the first time, shoot proliferation and plant regeneration protocols via shoot organogenesis from leaf explants of a medical and ornamental plant, Portulaca pilosa L. The optimal proliferation of axillary shoots was 6.2-fold within 30 days on Murashige and Skoog (MS) medium supplemented with 3.0 µM 6-benzyladenine (BA). Shoots could be induced directly from leaf explants, forming an average of 3.8 adventitious shoots per explant, on optimal MS medium supplemented with 1.0 µM thidiazuron (TDZ) and 0.1 µM α-naphthaleneacetic acid (NAA). A higher concentration of TDZ (3.0 µM), alone or in combination with 0.1 µM NAA, induced somatic embryo-like shoot buds and then developed into real shoots. Rooting was easier since roots were induced on all rooting media within one month. Half-strength MS medium free of plant growth regulators was best for rooting. Rooted plantlets were transferred to a sand: perlite (1:1, v/v) substrate, resulting in highest survival (90%). Plantlets showed more robust growth, however, on substrates of yellow mud: perlite (1:1, v/v) or peat soil: vermiculite: perlite (1:1:1, v/v). [ABSTRACT FROM AUTHOR]

There is evidence that the ongoing climate change is happening through nighttime rather than daytime warming. How such a daily-asymmetric warming modifies plant phenology is still unclear. We investigated the effects of asymmetric warming on bud break by daily monitoring seedlings belonging to 26 black spruce [Picea mariana (Mill.) BSP.] and 15 balsam fir [Abies balsamea (L.) Mill.] provenances from the native range in Canada. Seedlings were subjected to either daytime or nighttime warming in three growth chambers at temperatures ranging between 10 and 24 °C. On average, a warming of 4 °C advanced the timings of bud break in both species by 2.4 days, with the later phases being more sensitive to the treatment. Bud break of both species responded more strongly to daytime warming, with the bud break occurred 1.2 and 3.2 days earlier under daytime than nighttime warming in black spruce and balsam fir, respectively. A marked ecotypic differentiation was only observed in black spruce that originated from provenances distributed broadly across Canada, with seedlings from the warmest provenance completing bud break 8.3 days later than those from the coldest one. However, no significant effect of provenance was observed for balsam fir, the narrowly distributed species. Overall, the above results suggest that a higher temporal resolution such as temperatures during daytime and nighttime, and higher spatial resolution should be taken into account to improve the accuracy of phenological model predictions under global change scenarios. Phenological models based on daily average temperature should take into account the diverging impacts of asymmetric warming on plant phenology. Our findings may indicate that the influence of warming on plant phenology may be less dramatic than expected. [ABSTRACT FROM AUTHOR]

To investigate the mechanisms underlying salt tolerance, physiological parameters of six halophyte species [Vitex rotundifolia L., Clerodendrum inerme (L.) Gaertn, Phyla nodiflora (L.) Greene, Scaevola sericea Vahl, Alternanthera bettzickiana (Regel) Nichols, and Dracaena cambodiana Pierre ex Gagn] under NaCl stress in in vitro and in vivo culture tests were examined. Membership function analysis and cluster analysis divided the six species, based on their salt tolerance level, into three groups: Group 1 (highly salt tolerant) included C. inerme, A. bettzickiana and S. sericea; Group 2 (moderately salt tolerant) included P. nodiflora; Group 3 (weakly salt tolerant) included V. rotundifolia and D. cambodiana. In response to in vitro NaCl stress, all six species showed a significant increase in the activities of antioxidant enzymes. NaCl stress enhanced free proline content in the leaves of all six species. CAT, SOD activity and proline accumulation were significantly correlated with the growth of C. inerme, P. nodiflora and A. bettzickiana under in vitro NaCl treatment. We conclude that NaCl-tolerant plants may suffer slight damage within a certain salt concentration, as evidenced by the activities of antioxidant enzymes and the accumulation of free proline. Key message: Six halophytic species showed a different salt tolerance level under in vitro and in vivo culture tests, due to the activities of antioxidant enzymes and the accumulation of free proline. [ABSTRACT FROM AUTHOR]

Plants develop diverse adaptive traits in changeable environments, yet whether plant defense traits change during succession remains unclear. In this study, we investigated the young leaf physical traits (i.e., upright orientation of leaves, trichomes, an enhanced cuticle, and a multilayered epidermis) and leaf color trait (i.e., red pigmentation) of dominant plants in three subtropical forests. These forests included a pioneer forest, a mixed coniferous-broadleaved forest, and a monsoon-evergreen broadleaved forest representing early, middle, and later successional stages, respectively. Our results show that the red color trait in young leaves is related to anti-herbivory defense, and the percentage of species with red young leaves is higher in later than in early succession. Physical defense tends to be weaker for red young leaves than for green young leaves in early and middle successions. In addition, the number of defense traits of young leaves increases with succession. We speculate that young leaves in subtropical forests depend increasingly on multiple defense traits during succession because of the increased biotic stresses and environmental complexity in later succession. [ABSTRACT FROM AUTHOR]

Greenways help to conserve natural areas and improve the quality of life for residents, especially in cities experiencing rapid urbanization. In this study, we evaluated the landscape structure and network characteristics of Guangzhou's greenway system and analyzed the potential effects of natural and socioeconomic factors on the construction of urban greenways. The total length and density of the greenway system in Guangzhou was 1319.3 km and 0.18 km/km2, respectively. The greenway density in the urban regions was > 1.5 km/km2, which met the optimal threshold requirement for an urban greenway system. Guangzhou's greenway system had a total of 609 branches and 366 nodes, more than in Xiamen City (China) and Phoenix (AZ), which indicated a high level of network connectivity. The built-up area (area with residential, commercial, or industrial buildings) and the number of intersections of the transportation network were positively and linearly related (R2 = 0.46 and 0.78, respectively) to the length of Guangzhou's greenways in each 1-km2 pixel grid. Population density (R2 = 0.47, p < 0.001) and gross domestic product per capita (R2 = 0.75, p < 0.001) were positively correlated with the density of Guangzhou's greenways in each district. These results suggested that greenways were well distributed in the urban regions of Guangzhou. The slope was < 5° for 82.8% of Guangzhou's greenway system, which made it suitable for walking and biking; 43.7% of the 265 scenic spots were within 400 m, and 64.9% within 800 m, of the nearest greenway, indicating their high accessibility from greenways. However, nearly 50% (273 km) of the waterfront greenways in Guangzhou were adjacent to poor-quality water bodies. The future priority for optimizing Guangzhou's greenways should be the balancing of environmental protection with social and economic development. [ABSTRACT FROM AUTHOR]

The lower Ordovician mid-assemblage Formations in the central Ordos Basin of China host prolific gas resources, and most hydrocarbon reserves are stored in naturally-fractured reservoirs. Thus, fracture pathway systems may have a significant impact on reservoir performance. This article focuses on the core- and laboratory-based characterization of fractures. Through the developmental degrees, extended scale, output state and filling characteristics of various types of fractures, the results show that there are three distinct fracture types: 1) nearly vertical fractures, 2) oblique fractures, and 3) horizontal fractures. Based on a systematic study of the characterization of reservoir space, the main geologic setting of natural gas accumulation and the regional tectonic background, type 1 is mainly driven by the tectonic formation mechanism, and type 3 and parts of low-angle fractures in type 2 are induced by the diagenetic formation mechanism. While recovered paleopressure for methane-rich aqueous inclusions trapped in fracture-filling cement indicates that the fracture opening and growth are consistent with gas maturation and charge and such high-angle fractures in type 2 are caused by the compound formation mechanism. The fractures to hydrocarbon accumulation may play a more significant role in improving the quality of reservoir porosity. Furthermore, connected fractures, dissolved pores and cavities together constitute the three-dimensional pore-cave-fracture network pathway systems, with faults serving as the dominant charge pathways of highly pressurized gas in the study area. Our results demonstrate that protracted growth of a pervasive fracture system is not only the consequence of various formation mechanisms but also intrinsic to quasi-continuous accumulation reservoirs. [ABSTRACT FROM AUTHOR]

In the original article, some of the values in the fifth column of Table 2 and in the fifth and eighth columns of Table 4 are incorrect. The corrected values are in bold typeface in both tables below. [ABSTRACT FROM AUTHOR]

The article reports that the 2012 Rio+20 Summit focused on the need to develop integrated Sustainable Development Goals (SDGs) for achieving a harmonious relations among economic development, social inclusion, and environmental sustainability by 2030. Topics discussed include China's focus on sustainable land development, agriculture challenges facing China and its impact on land degradation, and problems facing ecosystems in China.

Subsurface damage and edge chipping remain a persistent technical challenge for the abrasive machining of dental restorations made from glass ceramics, and they impede the fabrication of long-lasting dental restorations. This paper reports on an integration of ultrasonic assistance to dental high-speed rotary abrasive machining for improvement of the surface quality of glass ceramics. An ultrasonic assisted computer-controlled high-speed rotary cutting apparatus was designed and fabricated with functions of ultrasonic vibration, automatic cutting, and force measurement. A multi-phase feldspar glass ceramic with the highest brittleness among glass ceramics was selected for the study. Machining forces, surface roughnesses, and edge chipping damage were evaluated for a range of cutting conditions with and without ultrasonic vibrations. Our most significant finding is that ultrasonic assisted machining led to a clear and consistent reduction of edge chipping and thus subsurface damage. Ultrasonic machining also achieved significant reductions in normal and tangential forces, and surface roughness at higher removal rates (p < 0.05). Our results suggest that ultrasonic assisted dental machining may be a way to improve quality and lifetime of ceramic dental restorations, whose failures are rooted in chipping damage and surface flaws using current machining techniques. [ABSTRACT FROM AUTHOR]

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