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In this paper, high-sulfur petroleum coke was used as the sulfur source and Gd2O2S powder was prepared by sulfurization of the Gd2O3 powder synthesized by homogeneous precipitation method. Gd2O2S:Eu3+ phosphor was also prepared by the same process. And the phase and morphology of the as-prepared product were studied by X-ray powder diffraction (XRD) and field emission scanning electron microscope (FE-SEM) techniques. The results indicated that the sulfurization product at 1000 ℃ is single phase Gd2O2S with quasi spherical shape when the Gd3+ ion concentration is only at 0.01 mol·L−1. Here the pyrolysis gases during high-temperature pyrolysis are evaluated by combining with high-temperature thermogravimetric analysis (TG), infrared analysis (IR), and mass spectrometry (MS). The results show that the petroleum coke pyrolysis gases are CO, H2O, CO2, H2S, SO2, and H2, roughly consistent with those of sample mass loss. In addition, the formation mechanism of Gd2O2S is also proposed. PL excitation and emission spectra show that when the concentration of Eu3+ ion is 9%, the PL excitation intensity is the strongest, and concentration quenching occurs. Under excitation at 321 nm light, the red emission of the Gd2O2S:9%Eu3+ phosphor has the strongest peak at 626 nm, which is attributed to the 5D0 → 7F2 transition of the Eu3+ ion. [ABSTRACT FROM AUTHOR]

Aims: Mycorrhizal fungi and microbial community play crucial roles in soil carbon (C) cycling within forest ecosystems. The various types of mycorrhizal fungi have distinct effects on the decomposition of soil organic C, primarily through their interactions with microbial members. However, there is currently a lack of understanding regarding the linkages between mycorrhizal types and microbial properties such as microbial keystone taxa and functions. Methods: In this study, we investigated the impact of converting ECM-dominated forests to AM-dominated forests on bacterial and fungal community composition, keystone taxa and potential functions by high -throughput sequencing. Results: The ECM fungal biomass in broadleaved forest soils showed a decrease of 45.07% compared to Masson pine forest soils. In contrast, the AM fungal biomass increased significantly by 25.57%. Our results demonstrated that the conversion from ECM- to AM-dominated forests enhanced soil organic carbon (SOC), total nitrogen (TN) and fungal diversity. There was no significant change in the microbial composition at the phylum level. Moreover, the conversion significantly altered the properties of microbial co-occurrence networks and the potential function of bacteria and fungi. Correlation analysis revealed close relationships between the relative abundance of microbial keystone taxa and microbial carbon degradation genes, as well as the biomass of mycorrhizal fungi. Conclusions: Our study suggested that the conversion of ECM- to AM-dominated forests altered microbial interaction, keystone taxa and function, which were significantly associated with changes in mycorrhizal fungal biomass and drove the increase in SOC content. [ABSTRACT FROM AUTHOR]

Purpose: Nanoscale zero-valent iron (nZVI) could degrade chlorinated pollutants like polychlorinated biphenyls (PCBs), but may be toxic to soil beneficial microbes such as arbuscular mycorrhizal (AM) fungi. The purpose of this work was to investigate the changes in community structure and diversity of AM fungi in PCBs-contaminated soils in response to input of nZVI, focusing on the balance between PCB dissipation and AM fungal conservation. Materials and methods: Both PCBs-amended (10 mg/kg Aroclor 1242, a PCB mixture) and control soils with three nZVI input levels (0.1, 1, and 10 g/kg) were tested in this 8-week incubation experiments. Soil pH and available P and PCB concentrations were determined, and the nested PCR amplification of the 18S rRNA gene of AM fungi was performed and sequenced on the Illumina MiSeq™ platform. Differences in soil AM fungal community structure were compared using principal component analysis (PCA). The redundancy analysis (RDA) was used to reveal the relationship between PCBs, soil properties, and AM fungal communities under different treatments. Results and discussion: Soil available P concentration significantly decreased as the nZVI input level increased, but only the high input level (10 g/kg) induced significantly higher soil pH and lower richness and Shannon and Simpson's indices of AM fungal communities compared to the low input case (0.1 g/kg). The presence of PCBs only led to differentiation in AM fungal communities in the low nZVI input case. In the PCBs-amended soils, both moderate (1 g/kg) and high input of nZVI significantly decreased the concentrations of di-, tri-, tetra-, penta-chlorinated biphenyls and total PCBs compared to the low input case, while the high input level only further significantly increased the dissipation of hexachlorinated biphenyls compared with the moderate input case. Conclusion: nZVI with high adsorption effects on soil available P had greater impacts on soil AM fungi than PCBs. However, the moderate nZVI input level (1 g/kg) had no significant effects on the richness and diversity indices of AM fungal community compared to the low input case (0.1 g/kg) and seemed to be more suitable for remediating of PCBs-contaminated soils, focusing on the limited inhibition on AM fungi. [ABSTRACT FROM AUTHOR]

This work experimentally investigates and compares terahertz electromagnetic shielding of micrometer-thick Ti3C2Tx MXene on polyimide prepared by two methods: etched using LiF/HF or HCl/HF from the MAX phase precursor. The later process shows a larger absorption coefficient as well as higher electrical conductivity. Raman spectroscopy and scanning electron microscopy are employed to probe the Tx termination, as well as, the structure of Ti3C2Tx MXene layer. It is found that the degree of oxygen termination resulting from the type of etchant play a significant role in bridging nearby titanium between the Ti3C2Tx MXene flakes. This is observed to increase the continuity of the Ti3C2Tx MXene surface and substantially enhances terahertz radiation shielding. [ABSTRACT FROM AUTHOR]

Purpose: The fixation of atmospheric CO2 and N2 by soil bacteria is important to the terrestrial carbon and nitrogen cycles and can be greatly affected by anthropogenic disturbance. The application of mineral fertilizer combined with manure (MCM) has been used to maintain soil quality and improve soil C storage. However, the impacts of MCM on soil CO2-fixing bacteria (CFB) and N2-fixing bacteria (NFB), encoded separately by the cbbL and nifH genes, remain largely unknown. Methods: In this study, we examined how the community structure of soil CFB and NFB from a chronosequence of Moso bamboo forests (6, 10, 15, and 20 years of intensive management) responded to long-term intensive management with MCM and identified the critical determinants that regulated them. Quantitative PCR and high-throughput pyrosequencing of the cbbL and nifH genes were used to analyze the abundance and community composition of CFB and NFB, respectively. Results: Employing MCM enhanced the content of SOC and soil available N, K, although some fluctuating values were observed over the 20-year period. The abundance of cbbL gene decreased significantly (P < 0.05) after 6 years of management and then recovered after 20 years of management. However, the abundance of nifH gene consistently declined over 20 years of management. The diversity of CFB increased significantly after 6 years of management, while that of NFB decreased significantly after 15 years of management compared to the no-fertilizer control. The phylum Proteobacteria was predominant in the CFB and NFB communities. Furthermore, the sum abundance of keystone taxa Rhodopseudomonas, Aminobacter, and Rubrivivax for CFB increased after 20 years of management, while the keystone taxon Bradyrhizobium for NFB decreased after 20 years of management compared to no-fertilizer control. Conclusions: In conclusion, the application of MCM favors the abundance, diversity, and keystone taxa of soil CFB rather NFB, which may improve soil C fixation. [ABSTRACT FROM AUTHOR]

In China, tuberculosis (TB) is endemic and the Bacillus Callmette–Güerin (BCG) vaccine is administered to all the newborns, which may lead to BCG infection in patients with chronic granulomatous disease (CGD). Infection of BCG/TB in CGD patients can be fatal and pulmonary is the most affected organ. Our objective was to assess the imaging of pulmonary BCG/TB infection in CGD. We screened 169 CGD patients and identified the patients with pulmonary BCG/TB infection. BCG infection was diagnosis according to the vaccination history, local infection manifestation, acid-fast bacilli staining, specific polymerase chain reaction, and/or spoligotyping. PPD, T-SPOT and acid-fast bacilli staining were used for diagnosis of TB. Totally 58 patients were identified, including TB (n = 7), solely BCG (n = 18), BCG + bacterial (n = 20), and BCG + fungi (n = 13). The onset of BCG disease was much earlier than TB. For those patients only with BCG, lymphadenopathy was the first and most prevalent feature. The most found location was the left axilla, followed by the ipsilateral cervical areas and mediastinal or hilar area. On chest CT, ground-glass opacities, multiple nodules and pulmonary scarring were the most common findings. For TB patients, the pulmonary infections were more serious, including large masses, severe lymphadenopathy, and extensive pulmonary fibrosis. Pulmonary infection of BCG were more common than TB in CGD patients, but much less severe. [ABSTRACT FROM AUTHOR]

Introduction: Systemic sclerosis (SSc) is associated with interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH). This study aimed to explore the prevalence, clinical features, hemodynamic characteristics and prognosis of different severity of ILD in a cohort of patients with SSc-associated precapillary pulmonary hypertension (SSc-PH) and investigate the differences between SSc-PAH and idiopathic pulmonary arterial hypertension (IPAH) patients. Method: SSc-PH patients and IPAH patients, admitted to Shanghai Pulmonary Hospital (August 1, 2008–January 31, 2020) and diagnosed by right-sided heart catheterization (RHC) or echocardiography, were retrospectively included. SSc-PH patients had a baseline chest high-resolution computed tomography (HRCT), and PH classification was based on the extent of ILD. Clinical, pulmonary function, hemodynamic characteristics and survival data were extracted. Results: The study included 45 SSc-PH patients (60% had coexisting ILD and 77.8% were SSc-Group 1 PH/SSc-PAH [without ILD or with mild ILD], 22.2% were SSc-Group 3 PH/SSc-PH with severe ILD) and 52 IPAH patients. SSc-PH with ILD had lower arterial oxygen partial pressure (PaO2) than those without ILD. Hemodynamic characteristics and survival rates were comparable between SSc-PAH with mild ILD and those without ILD. SSc-Group 3 PH had lower pulmonary vascular resistance (PVR) and more severe restrictive ventilatory dysfunction than SSc-Group 1 PH, but the survival rate was equally poor. SSc-PAH had a poorer prognosis than IPAH patients despite the better hemodynamic characteristics. Conclusions: ILD was common in SSc-PH patients. Careful phenotyping of PH in SSc-PH patients is very important as it is imperative to recognize its impact on clinical course, treatment and survival. Key Points: • ILD was common in Chinese SSc-PH patients. • SSc-PH patients with ILD had lower PaO2 than those without ILD. • Hemodynamic characteristics and survival rates were similar in SSc-PAH patients with mild ILD and those without ILD. • Patients in SSc-Group 3 PH had lower pulmonary vascular resistance (PVR) and more severe restrictive ventilatory dysfunction than those in SSc-Group 1 PH, but the survival rate was equally poor. SSc-PAH patients had a poorer prognosis than IPAH patients despite their better hemodynamic characteristics. [ABSTRACT FROM AUTHOR]

Purpose: Biochar and organic amendments can improve soil quality, but their combined effects on plant growth as well as soil microbial functions deserve further investigation. Materials and methods: We established an 8-month field experiment to explore the effects of biochar (0, 10 t ha−1), organic amendments (10 t ha−1 sheep manure and 2 t ha−1 rapeseed cake), and their combinations on plant growth and soil quality in a Torreya grandis plantation. Results and discussion: Organic amendments significantly (P < 0.05) increased soil available and total P contents as well as mineral nutrients in leaves. Biochar significantly increased soil available P and K and total K contents. Biochar combined with sheep manure rather than rapeseed cake displayed a significant (P < 0.05) increase in plant quality and soil nutrients in comparison with manure or rapeseed cake addition alone. Biochar combined with sheep manure significantly increased microbial activity (indicated by microbial substrate utilization rate) compared with manure alone treatment. In addition, organic amendments in combination with biochar generally had no significant effects on microbial diversity indices, but they had some interactive effects on some bacterial taxa, such as Proteobacteria and Actinobacteria, and predicted metabolism functions. Changes in soil nutrient contents were closely linked with soil bacterial community composition and improvements in plant quality. Conclusions: The results showed that 10 t ha−1 biochar co-applied with 10 t ha−1 sheep manure was suitable for the promotion of soil fertility and plant growth in a Torreya grandis plantation. [ABSTRACT FROM AUTHOR]

Bone marrow mesenchymal stem cells (BMSCs) have been shown to promote stroke recovery, however, the underlying mechanisms are not well understood. In this study naïve rats were intravenously injected with syngeneic BMSCs to screen for potential differences in brain metabolite spectrum versus vehicle-treated controls by capillary electrophoresis-mass spectrometry. A total of 65 metabolites were significantly changed after BMSC treatment. Among them, 5-oxoproline, an intermediate in the biosynthesis of the endogenous glutathione (GSH), was increased. To confirm the obtained results and investigate the metabolic pathways, BMSCs were injected into rats 24 h after middle cerebral artery occlusion (MCAO). Rats receiving vehicle solution and sham-operated animals served as controls. High performance liquid chromatography, reverse transcription-quantitative polymerase chain reaction, and Western blotting revealed that intravenous BMSC application increased the levels of 5-oxoproline and GSH in MCAO rats, as well as the expression of key enzymes involved in GSH synthesis including, gamma-glutamylcyclotransferase and gamma-glutamylcysteine ligase. Subsequent clinical investigation confirmed that acute ischemic stroke patients had higher plasma 5-oxoproline and GSH levels than age- and sex-matched non-stroke controls. The optimal cutoff value for 5-oxoproline diagnosing acute ischemic stroke (≤ 7d) was 3.127 µg/mL (sensitivity, 63.4 %; specificity, 81.2 %) determined by receiver characteristic operator curve. The area under the curve was 0.782 (95 % confidence interval: 0.718–0.845). Our findings indicate that BMSCs play a protective role in ischemic stroke through upregulation of GSH and 5-oxoproline is a potential biomarker for acute ischemic stroke. Ischemic stroke causes oxidative stress and induction of endogenous, glutathione-dependent anti-oxidative mechanisms. 5-oxoproline, an important metabolite in glutathione biosynthesis, could serve as a biomarker of acute ischemic stroke. Moreover, intravenous bone marrow mesenchymal stem cell (BMSC) treatment after experimental stroke upregulates the expression of key enzymes involved in glutathione synthesis, which results in better antioxidative defense and improved stroke outcome. [ABSTRACT FROM AUTHOR]

In modern optical design, the calculation of optical merit function based on the ray tracing would be impossible without the aid of a computer. Finding the optimal value of merit function by optimization techniques would also be impossible without the aid of a computer. With the rapid development of computer technology and the emergence of novel optimization techniques, it is a beneficial attempt to apply new optimization techniques to optical design with the aid of high-performance computers, so as to realize intelligent and quick design of the image acquisition lens of high precision. In this paper, the optimization technique of ant colony is employed to design an iris image capture lens consisting of two aspheric lenses with the aid of a desktop computer of a 64-bit processor and dual-core CPU, and the detailed design steps are presented. Imaging performance of the designed image acquisition lenses is quantitatively evaluated by using Zemax software, and the analysis shows that high-resolution image with MTF > 0.4 at the Nyquist frequency of 223 lp/mm below 0.8 field of view (FOV) and optical distortion of less than 0.2% below 0.5 FOV can be acquired, demonstrating a great potential of the ant colony optimization algorithm in quickly designing high-quality optical lenses. We also apply the ACA to the benchmark problems for lens design problem and demonstrated that this method can provide high-quality solution. [ABSTRACT FROM AUTHOR]

It is necessary to select the appropriate parameters defining a aspheric lens for coupling the light from a laser diode into the optical fiber by cap aspheric lenses. In this paper, the ant colony optimization algorithm is applied to the optimization of structural parameters of the cap aspheric lens, and the merit function defining the optimization problem and detailed design steps are given. A cap aspheric lens with center thickness of 1.1019 mm and effective focal length of 1.10331 mm is designed using a self-made MATLAB program of ant colony optimization algorithm, which can couple the light emitting from a laser diode into a single mode fiber with a diameter of 9 um, the light-emitting surface of the LD is 3 µm × 2 µm, and beam-divergence angle in the X and Y directions are ± 35° and ± 23.58°, respectively. The theoretical coupling efficiency is 89.8%, and the experiment shows that the maximum coupling efficiency and average coupling efficiency are 88.63% and 79.39%, respectively. Design and experimental results prove that the design method in this paper is feasible and effective. [ABSTRACT FROM AUTHOR]

Aims: Invasive plants not only alter aboveground biodiversity but also belowground microbial community composition to facilitate their growth and competitiveness. However, how plant invasion affects soil microbial resource limitation and metabolic activity, and their linkages with litter and soil stoichiometries remain largely unknown. Methods: We investigated the carbon (C): nitrogen (N): phosphorus (P) stoichiometries of litter, soil, microbe and extracellular enzymes, composition of main microbial groups and substrate utilization rate in a subtropical forest invaded by Moso bamboo (Phyllostachys edulis) and those in adjacent broadleaf and mixed bamboo-broadleaf forests. Results: Bamboo invasion significantly decreased annual litter production, litter C: P and N: P ratios, and soil C:N and C:P ratios, whereas increased microbial biomass C:N and C:P ratios, resulting in decreased C:N and C:P imbalances between soil microorganisms and their resources. Bamboo invasion decreased the N and P acquiring enzymes activities, mitigated the status of microbial N and P limitation as indicated by enzymatic stoichiometry, and caused a higher C use efficiency. Soil microbial community structure was shifted towards a lower fungi: bacteria (F:B) ratio in bamboo forest. Bamboo forest soil showed a lower capacity of microbes to use N-rich resources in comparison to C-rich resources. Structural equation modeling suggested a direct and negative effect of C:N imbalance on microbial N limitation and metabolic capacity. Conclusions: This study suggests the importance of stoichiometric imbalance between decomposers and their resources in regulating soil microbial community structure and enzyme activities following plant invasion. [ABSTRACT FROM AUTHOR]

A field experiment was carried out to study the responses of soil respiration, soil C and N, composition of main microbial groups, enzyme activity, and microbial C source utilization to two organic amendments (i.e., straw and manure) added alone or combined with biochar for 9 months in an infertile soil. In comparison with the non-amended control, soil CO2 emission rates were significantly increased following straw and manure addition, but they were decreased by 19% and 36% on average when co-applied with biochar. Organic amendments significantly increased the size of labile C pool by 21%, total phospholipid-fatty acid (PLFA) concentrations by 32%, activities of α-glucosidase by 51%, β-glucosidase by 115%, β-D-cellobiosidase by 105%, β-xylosidase by 43%, phenol oxidase by 59%, and peroxidase by 91% on average relative to the non-amended control, whereas biochar co-application with organic amendments had no effect on soil PLFA concentrations but significantly decreased the enzyme activities by 38% and the sizes of labile C and N pools by 16% on average. The results of the substrate-induced respiration confirmed a lower capacity of biochar-treated soils to use the C sources of carbohydrates and carboxylic acids. Structural equation modeling indicated that the response of soil CO2 emission rates to organic amendment and biochar was directly linked to their effects on microbial activities. Therefore, our study demonstrated that biochar co-applied with straw or manure mitigated soil C loss by decreasing soil microbial activities. [ABSTRACT FROM AUTHOR]

The distributed clustering method is widely used to extend network lifetime in traditional wireless sensor networks. However, it is difficult to achieve the idea performance of the whole network, such as transmission rate, energy consumption, and control overhead, neglecting the global stability of the network. To tackle this problem, a centralized mobility-based clustering (CMBC) protocol is proposed in the software defined sensor network. The method of CMBC mainly consists of two aspects: first, CMBC clusters the nodes with the connection time between the mobile nodes (i.e., noncluster head nodes, non-CH) and the cluster head (CH) and establishes stable topological structures between the non-CHs and the CH; second, when emergencies occur, the centralization management control center sends the configuration files to replace the CH. Compared to the distributed network of MBC, WCRA and IMP-MECA protocol, the proposed method can be applied in scenarios with high-speed mobile nodes to improve the network performance in terms of transmission successful rate, average power consumption, and average control overhead. [ABSTRACT FROM AUTHOR]

Autotaxin (ATX) is a secreted enzyme that hydrolyzes lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA) and choline. ATX has been implicated in multiple chronic inflammatory diseases, but little is known about its role in the development of inflammatory bowel disease (IBD). Here, we investigated how ATX contributed to intestinal inflammation during colitis. We found that ATX expression levels were upregulated in the intestines of ulcerative colitis (UC) patients in acute state as well as in the intestines of dextran sulfate sodium (DSS)-induced colitis mice, which is likely due to increased infiltration of inflammatory cells including macrophages. Intriguingly, the inhibition of ATX activity led to reduced production of inflammatory cytokines, as well as attenuated colitis. These findings suggest that ATX may display strong pro-inflammatory properties. Supporting this, treatment with recombinant mouse ATX (rmATX) increased the production of inflammatory cytokines and enzymes in mouse macrophage cell line RAW264.7 and bone marrow-derived macrophages (BMDM), whereas silencing ATX by siRNA reduced LPS-stimulated production of pro-inflammatory factors. Notably, we found that the levels of LPA2 (an LPA receptor) were dramatically upregulated in rmATX-treated RAW264.7 cells and DSS-treated mice. Gene silencing of lpa2 in RAW264.7 cells by siRNA led to reduced production of inflammatory cytokines. Moreover, adenovirus-mediated delivery of lpa2 short hairpin RNA into DSS-treated mice ameliorated colitis. Collectively, our research suggests that ATX may exacerbate DSS-induced colitis by activating LPA2 receptor in macrophages and represent a promising target for the treatment of IBD. Key messages: Increased ATX expression and secretion in colitic colons are likely due to increased infiltration of inflammatory cells including macrophages. Recombinant ATX promotes, but ATX silencing inhibits, the production of inflammatory cytokines in LPS-stimulated RAW264.7 cells and BMDM. •LPA2 mediates the pro-inflammatory effects of ATX on macrophages. Inhibition of ATX and downregulation of LPA2 ameliorate DSS-induced colitis. [ABSTRACT FROM AUTHOR]

Soil salinity is widespread in rice-producing areas globally, restricting both vegetative growth and grain yield. Improving salt tolerance of rice is a promising approach to meet the increasing food demand. An extensive literature survey indicates that maintaining proper Na+/K+ ratio and reactive oxygen species (ROS) content is the key issues for rice adaption to salt stress. In this review, distinctive from the existing reviews, we mainly discuss recent progresses in identifying the components and pathways involved in the rice response to salt stress and the approaches that can be used for breeding and cultivating salt-tolerant rice, pointing out the potential phytohormonal regulation of the components and the homeostasis of Na+/K+ and ROS. Thus, this review attempts to provide a comprehensive overview of the recent research on rice adaption to salt stress, which may provide guidance for rice breeding to engineer better salt-tolerant rice varieties. [ABSTRACT FROM AUTHOR]

A meta-study of 83 articles published from 1981 to 2016 was conducted on Hispanics access to health care in the US. Few of these studies have included acculturation and even fewer the role of social capital as important factors that impact healthcare access for this population. Among those that do include these two factors, there is confusion as to how they are defined and operationalized. Acculturation and social capital could serve to overcome some of the structural barriers in place that manifest stronger among Hispanics who are relatively newcomers to a healthcare system that is highly complex to navigate. The majority of studies included in this systematic review of the literature are in public health journals, which do not focus on sociological aspects as much. This study exposes the need to expand the worldviews used in the literature in order to enrich our understanding of access to health care for Hispanics. [ABSTRACT FROM AUTHOR]

The role of soil organic C (SOC) quality affecting microbial community composition and function under biochar application is poorly understood. We investigated the relationship between the pool size and chemical composition of SOC; composition of main microbial groups; enzyme activities involved in C, N, and P cycling; and soil respiration in a rice paddy amended with biochar for 20 months in a laboratory experiment at 15, 25, and 35 °C. Soil labile and recalcitrant organic C pools were determined by a two-step sulfuric acid (H2SO4) hydrolysis method. The chemical composition of SOC was determined with 13C-nuclear magnetic resonance spectroscopy. The biochar amendment at 20 and 40 t ha−1 significantly decreased the soil labile C pool I (extracted by 5 N H2SO4), alkyl, and carbonyl C contents and increased the recalcitrant C pool (acid-resistant) and aromatic C contents and the aromatic C to O-alkyl C ratio. The phospholipid-fatty acid concentrations and soil enzyme activities were unchanged by biochar application at 10 and 20 t ha−1, but both were increased at 40 t ha−1. Biochar increased the ratio of gram-positive (G+) to gram-negative (G−) bacteria and decreased that of fungi to bacteria. The recalcitrant C pool and aromatic C contents were positively correlated to the G+ bacteria abundance and were important factors in shaping composition of the main microbial groups and improving enzyme activities. Biochar application at 40 t ha−1 lowered soil respiration rates at 15 and 25 °C by decreasing labile C pool and increasing C recalcitrancy while increased temperature sensitivities of soil respiration at 25/15 °C and 35/25 °C by stimulating microbial abundance and enzyme activities. Together, our results suggest that biochar soil amendment shifted microbial community composition and function through influencing the composition of SOC. [ABSTRACT FROM AUTHOR]

Biochar amendment has been advocated as an effective method to remediate organic pollutant-contaminated soils through adsorption and stimulating microbial degradation. However, such effects can vary depending on soil properties and biochar physiochemical characteristics. The objective of this study was to compare the dynamic variations of polychlorinated biphenyls (PCBs) in low and high soil organic carbon (SOC) soils both amended with biochar and to investigate its linkage with fungal community composition. Two soils having the same texture and soil type but varying in SOC contents were contaminated with PCBs to a final concentration of 60 mg kg−1 and amended with 2% bamboo biochar. Temporal changes of PCB remaining in soils and adsorbed on biochar particles were determined during a 2-month incubation. Diversity and composition of fungal communities in both low and high SOC soils were investigated with Illumina MiSeq sequencing. The results showed that the PCB concentrations in low SOC soil were significantly lower than those in high SOC soil during the incubation. In the low SOC soil, the biochar particle adsorbed higher amounts of PCB, tetra-, and penta-chlorobiphenyls (CBs) than those in high SOC soil, and stimulated the dissipation of di- and tri-CBs. The nonmetric multidimensional scaling profile showed significant (p < 0.05) differences in the fungal community composition between the low and high SOC soils. The relative abundances of Eurotiomycetes were gradually increased, whereas those of Sordariomycetes and Dothideomycetes were decreased with increasing incubation time in the low SOC soils. In contrast, the fungal communities in high SOC soils were relatively stable. The relative abundances of Eurotiomycetes and Sordariomycetes were positively correlated with PCB dissipation in low and high SOC content soils, respectively. Our results suggest that SOC content affects PCB dissipation and fungal community composition in biochar-amended soils, and biochars have a high remediation potential of PCB in soils with low SOC contents. [ABSTRACT FROM AUTHOR]

In order to design a complex laser resonator with multi-parameters, the method of particle swarm optimization (PSO) algorithm is employed. The parameters influencing the resonator stability and mode size distribution are taken into consideration, and the stability criteria index and the mode size distribution are used as target values. The absolute values of the differences between practical and the target values are set as the fitness function for the PSO. By minimizing the fitness function, a laser resonator with the optimized cavity parameters can be found. The analyses for the design example demonstrate the feasibility and validity of the PSO method in the computer aided design of multi- parameters laser resonator. Applying PSO algorithm in the intelligent design of solid state laser resonators can realize the transition from manual trial-and-error to computer intelligent design of the laser resonators. [ABSTRACT FROM AUTHOR]

Transplantation of motor neurons can provide long-term functional benefits in animal models of neurodegenerative motor neuron diseases such as amyotrophic lateral sclerosis and traumatic spinal cord injury. Although embryonic stem cells can differentiate into motor neurons, alternative sources of motor neurons may be controllable for disease modeling and transplantation. Here, we show that human and mouse fibroblasts can be efficiently and directly converted into motor neurons by a cocktail of five small molecules, without the involvement of the neural progenitor stage. The chemically-induced motor neurons display the distinct neuronal morphology and express motor neuron markers. Interestingly, when the same chemical compounds were soaked in beads and implanted in the hypodermis of the back skins of mice, surrounding cells begin to express motor neuron markers, indicating in vivo motor neuron reprogramming. Taken together, we provide an efficient approach for chemically converting human and mouse fibroblasts into motor neurons suitable for cell replacement therapy and neurodegenerative disease modeling. [ABSTRACT FROM AUTHOR]

Chemical modulation of cell fates has been widely used to promote tissue and organ regeneration. Small molecules can target the self-renewal, expansion, differentiation, and survival of endogenous stem cells for enhancing their regenerative power or induce dedifferentiation or transdifferentiation of mature cells into proliferative progenitors or specialized cell types needed for regeneration. Here, we discuss current progress and potential using small molecules to promote in vivo regenerative processes by regulating the cell fate. Current studies of small molecules in regeneration will provide insights into developing safe and efficient chemical approaches for in situ tissue repair and regeneration. [ABSTRACT FROM AUTHOR]

Aims: Moso bamboo ( Phyllostachys pubescens) is a fast-growing species that can invade neighboring forests through its vigorous rhizome system, leading to large shifts of plant diversity and soil properties. A primary concern is the response of arbuscular mycorrhizal fungal (AMF) communities and related soil C sequestration to bamboo forest expansion. Methods: We used a long-term soil chronosequence from primary broadleaved forest to moso bamboo forest to examine the changes in AMF abundance and communities, as well as their role in soil C storage. Results: AMF communities showed strong niche differentiation, and were highly structured by forest type ( r = 0.648, P = 0.001), and marginally correlated to soil pH and organic C. Bamboo forest expansion increased soil AMF biomass as indicated by neutral lipid fatty acids (NLFA) 16:1ω5 abundance, easily extracted glomalin-related soil protein (EE-GRSP), and water-stable macroaggregates. We observed that soil AMF biomass contributed substantially to both soil macroaggregates and EE-GRSP, which were tightly correlated with soil organic C. The influence of bamboo forest expansion on soil C sequestration was mainly due to its indirect effect on AMF biomass. Conclusions: Bamboo forest expansion significantly changed soil AMF communities and increased AMF biomass, which in turn contributed to enhanced soil aggregation and C storage. [ABSTRACT FROM AUTHOR]

The rectification of terahertz radiation due to plasmonic nonlinearities in a periodic graphene structure with a dual-grating gate and an asymmetric unit cell is considered. The influence of unit-cell asymmetry on the plasmonic rectification of the terahertz radiation near higher plasmonic resonances is considered for the cases of electron and hole conduction in parts of the graphene unit cell. The current responsivity of the rectification of terahertz radiation due to the plasmonic effects of differential charge-carrier drag and electron-hole ratchet is calculated. [ABSTRACT FROM AUTHOR]

Pluripotency reprogramming and transdifferentiation induced by transcription factors can generate induced pluripotent stem cells, adult stem cells or specialized cells. However, the induction efficiency and the reintroduction of exogenous genes limit their translation into clinical applications. Small molecules that target signaling pathways, epigenetic modifications, or metabolic processes can regulate cell development, cell fate, and function. In the recent decade, small molecules have been widely used in reprogramming and transdifferentiation fields, which can promote the induction efficiency, replace exogenous genes, or even induce cell fate conversion alone. Small molecules are expected as novel approaches to generate new cells from somatic cells in vitro and in vivo. Here, we will discuss the recent progress, new insights, and future challenges about the use of small molecules in cell fate conversion. [ABSTRACT FROM AUTHOR]

Since the lacZα-based blue/white screening system was introduced to molecular biology, several different visual reporter systems were developed and used for various purposes in Escherichia coli. A common limit to the existent visual reporter systems is that an extracellular chromogenic substrate has to be added for the visible pigment production. In this study, we developed a new blue/white screening system based on a non-ribosomal peptide synthetase encoded by idgS from Streptomyces and a phosphopantetheinyl transferase encoded by sfp from Bacillus. When IdgS is activated from an apo-form to a holo-form via a posttranslational modification catalyzed by Sfp, it can synthesize a blue pigment indigoidine using L-glutamine, the amino acid abundant in cells, as a substrate. The new blue/white screening system contains a recipient E. coli strain with an optimized idgS gene cassette and a cloning vector harboring an sfp gene with an in-frame insertion of a multiple cloning site close to its N-terminal. We demonstrated that the IdgS/Sfp-based blue/white screening system is a powerful alternative to the lacZα-based screening system, which does not require any external substrate addition. [ABSTRACT FROM AUTHOR]

The article focuses on qualitative comparative analysis (QCA) of selected community-based forest management (CBFM) and the use of a unique applied social science technique and accumulation of empirical studies on community based natural resource management (CBNRM).

Somatic cells can be reprogrammed to pluripotent stem cells or transdifferentiate to another lineage cell type. Much efforts have been made to unravel the epigenetic mechanisms underlying the cell fate conversion. Histone modifications as the major epigenetic regulator are implicated in various aspects of reprogramming and transdifferentiation. Here, we discuss the roles of histone modifications on reprogramming and transdifferentiation and hopefully provide new insights into induction and promotion of the cell fate conversion by modulating histone modifications. [ABSTRACT FROM AUTHOR]

Rural, high-amenity areas in the USA continue to attract significant numbers of migrants. A common approach to investigating the potential consequences of rural in-migration is to contrast the characteristics, attitudes, and/or actions of migrants and non-migrants (or 'newcomers' and 'oldtimers'). However, no consensus exists on the distinctions (or the lack thereof) between these two groups in the existing literature, in part because previous research used a variety of methods to classify residence status. Drawing on household survey data from nine communities in north-central Colorado, this study illustrates how different categorizations may yield different conclusions. Categorizing resident groups by the 1970/1980 cutoff or 5-, 10-, or 20-year length of residence substantially altered the differences and similarities between newcomers and oldtimers in selected sociodemographic, perceptual, and behavior indicators. It is recommended that researchers choose the most appropriate classification approach based on specific research questions and objectives as well as important transitions in the migration patterns of their study areas. These findings have direct implications for future research on rural demographic change and socioeconomic restructuring. [ABSTRACT FROM AUTHOR]

In light of the rapid urbanization of the world's population over the past decades, there is a growing concern about the environmental impacts of urban population growth. Rural-urban migration is a particularly important component of the urbanization process in developing countries and is often considered to be detrimental to urban environmental conditions. However, few studies have explicitly examined the presumed negative impacts of in-migration on the natural environment of cities. The continuously increasing volume of rural-urban labor migration in China since the early 1980s has formed the largest population flow in world history. This study links the existing literature on population-environment and urbanization-environment interactions by empirically assessing the relationship between rural-urban migration and urban air conditions in China. A two-period (2004 and 2010) longitudinal dataset for the 113 key environmental protection cities of China was constructed based on multiple data sources. We applied the STIRPAT equation using conventional and spatial panel regression models to examine whether rural-urban migration flows were associated with air pollution in cities. Results show a strong negative association of in-migration with urban air quality even after controlling for the effects of other population, affluence, and technology factors. Findings from this research can contribute to a better understanding of the environmental consequences of rural-urban migration in China, with broader implications for sustainable development research and policies. [ABSTRACT FROM AUTHOR]

Root determines plant distribution, development progresses, stress response, as well as crop qualities and yields, which is under the tight control of genetic programs and environmental stimuli. Ethylene responsive factor proteins (ERFs) play important roles in plant growth and development. Here, the regulatory function of OsERF2 involved in root growth was investigated using the gain-function mutant of OsERF2 ( nsf2857) and the artificial microRNA-mediated silenced lines of OsERF2 ( Ami- OsERF2). nsf2857 showed short primary roots compared with the wild type (WT), while the primary roots of Ami- OsERF2 lines were longer than those of WT. Consistent with this phenotype, several auxin/cytokinin responsive genes involved in root growth were downregulated in nsf2857, but upregulated in Ami- OsERF2. Then, we found that nsf2857 seedlings exhibited decreased ABA accumulation and sensitivity to ABA and reduced ethylene-mediated root inhibition, while those were the opposite in Ami- ERF2 plants. Moreover, several key genes involved in ABA synthesis were downregulated in nsf2857, but unregulated in Ami- ERF2 lines. In addition, OsERF2 affected the accumulation of sucrose and UDPG by mediating expression of key genes involved in sucrose metabolism. These results indicate that OsERF2 is required for the control of root architecture and ABA- and ethylene-response by tuning expression of series genes involved in sugar metabolism and hormone signaling pathways. [ABSTRACT FROM AUTHOR]

GDP- d-mannose pyrophosphorylase (GMPase) catalyzes the synthesis of GDP- d-mannose, which is a precursor for ascorbic acid (AsA) synthesis in plants. The rice genome encodes three GMPase homologs OsVTC1- 1, OsVTC1- 3 and OsVTC1- 8, but their roles in AsA synthesis are unclear. The overexpression of OsVTC1- 1 or OsVTC1- 3 restored the AsA synthesis of vtc1- 1 in Arabidopsis, while that of OsVTC1- 8 did not, indicating that only OsVTC1- 1 and OsVTC1- 3 are involved in AsA synthesis in rice. Similar to Arabidopsis VTC1, the expression of OsVTC1- 1 was high in leaves, induced by light, and inhibited by dark. Unlike OsVTC1- 1, the expression level of OsVTC1- 3 was high in roots and quickly induced by the dark, while the transcription level of OsVTC1- 8 did not show obvious changes under constant light or dark treatments. In OsVTC1- 1 RNAi plants, the AsA content of rice leaves decreased, and the AsA production induced by light was limited. In contrast, OsVTC1- 3 RNAi lines altered AsA synthesis levels in rice roots, but not in the leaves or under the light/dark treatment. The enzyme activity showed that OsVTC1-1 and OsVTC1-3 had higher GMPase activities than OsVTC1-8 in vitro. Our data showed that, unlike in Arabidopsis, the rice GPMase homologous proteins illustrated a new model in AsA synthesis: OsVTC1-1 may be involved in the AsA synthesis, which takes place in leaves, while OsVTC1-3 may be responsible for AsA synthesis in roots. The different roles of rice GMPase homologous proteins in AsA synthesis may be due to their differences in transcript levels and enzyme activities. [ABSTRACT FROM AUTHOR]

Arsenic (As) contamination has become the environment issue of global concern. In China, large area of farmland and the site soil were contaminated by As, which means that suitable remedying methods were urgently needed. Phytoremediation, as one of environment-friendly soil remediation techniques developed in recent years, shows a bright future for the remediation of As contaminated soils. However, phytoremediation efficiency needs to be enhanced further because of low concentration of bio-available As in the soils. A triangle flask culture experiment was carried out to study the effects of functional species, isolated from As-polluted soils, that could improve As mobility from the soil. These species included two bacilli, B1 and B2 ( Brevibacillus) and two fungi, F1 ( Trichoderma), F2 ( Fusarium). They could transform the concentration of As fractionation in the soil sterilized by the method of Co-γ ray. Through the experiment, the concentrations of non-specifically-sorbed and specifically-sorbed As fractionation, and pH value of culture solution with inoculated treatment were higher than that with the control. Especially, the concentration of non-specifically-sorbed As fractionation in the treatment-inoculated species was 2 to 6 times higher than that of non-inoculation treatment. Moreover, two bacilli and two fungi could produce IAA, which was conducive to the plant survival when they were jointly used in remedying the As-contaminated soil. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the clinical effect of sequential therapeutic intervention Yupei Qisun [compensating for weakness by invigorating Kidney (Shen) and Spleen (Pi) in advance] in Chinese medicine (CM) and hysteroscopic endometrial mechanical stimulation on the treatment of infertile patients with repeated implantation failure (RIF); and to study the differences in patients' endometrial thickness and type on the day of embryo transfer, serum hormone levels on embryo transfer day and clinical pregnancy outcomes. Methods: In the clinical study, 168 frozen-thawed embryo transfer (FET) cycles for couples with RIF conforming to the research protocol were randomly divided into three groups: a CM group with 56 cycles (CM combined with FET), a hysteroscopy group with 55 cycles (hysteroscopic endometrial mechanical stimulation), and a control group with 57 cycles (conventional FET). Differences in endometrial thickness on the embryo transfer day, levels of serum estradiol (E) and progesterone (P) on the embryo transfer day, the E/P ratio on the embryo transfer day, biochemical and clinical pregnancy rates, implantation rate, abnormal pregnancy rate and other indices were compared among the three groups. Results: Endometrial thickness, E and P levels, and the E/P ratio on embryo transfer day and other factors had no significant differences among groups. The biochemical pregnancy, clinical pregnancy, and implantation rates of the CM and hysteroscopy groups were significantly higher than the control group ( P<0.05), and there were no significant differences between these two groups. The abnormal pregnancy rate had no significant difference among the three groups. Conclusions: Sequential therapy of Yupei Qisun could significantly improve the clinical outcomes of RIF-FET cycles, being equivalent to hysteroscopic endometrial mechanical stimulation, and provided a reliable method to treat such infertile couples: [ABSTRACT FROM AUTHOR]

Phthalic acid esters have been used as plasticizers in numerous products and classified as endocrine-disrupting compounds. As China is one of the largest consumers of phthalic acid esters, some human activities may lead to the accumulation of phthalic acid esters in soil and result in contamination. Therefore, it is necessary for us to understand the current contamination status and to identify appropriate remediation technologies. Here, we reviewed the potential sources, distribution, and contamination status of phthalic acid esters in soil. We then described the ecological effect and human risk of phthalic acid esters and finally provided technologies to remediate phthalic acid esters. We found that (1) the application of plastic agricultural films, municipal biosolids, agricultural chemicals, and wastewater irrigation have been identified as the main sources for phthalic acid ester contamination in agricultural soil; (2) the distribution of phthalic acid esters in soils is determined by factors such as anthropogenic behaviors, soil type, properties of phthalic acid esters, seasonal variation, etc.; (3) the concentrations of phthalic acid esters in soil in most regions of China are exceeding the recommended values of soil cleanup guidelines used by the US Environmental Protection Agency (US EPA), causing phthalic acid ester in soils to contaminate vegetables; (4) phthalic acid esters are toxic to soil microbes and enzymes; and (5) phthalic acid ester-contaminated soil can be remedied by degradation, phytoremediation, and adsorption. [ABSTRACT FROM AUTHOR]

Oxidized low density lipoprotein (oxLDL) can trigger intracellular production of reactive oxygen species and lipid peroxidation (LPO), and is thought to contribute to initiation and progression of atherosclerosis. In order to understand the correlation between oxLDL and macromolecular damage, we measured levels of LPO-derived miscoding etheno-DNA adducts and LPO-modified proteins in cultured human vascular endothelial and smooth muscle cells after incubation with oxLDL for up to 48 h. A semi-quantative analysis method for 1, N-ethenodeoxyadenosine (ɛdA) by immunohistochemistry was applied. After oxLDL stimulation, ɛdA-stained nuclei were significantly increased in both endothelial and smooth muscle cells. Similarly, 4-hydroxy-2-nonenal (4-HNE)-modified proteins, as analyzed by immunohistochemistry and Western blotting, were also 3-5 fold increased. It was concluded LPO-derived etheno-DNA adducts and LPO-modified proteins are strongly induced by oxLDL in human vascular endothelial and smooth muscle cells. This macromolecular damage may contribute to the dysfunction of arterial endothelium and the onset of atherosclerosis. [ABSTRACT FROM AUTHOR]