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Phenolic resin (PF) is thermosetting resin with excellent overall performance, including good mechanical properties, high heat resistance, good carbon retention ability, excellent electrical insulation, and high mechanical strength. Compared to tar and asphalt, PF (phenolic resin) binders offer several advantages, including superior bonding properties, excellent wetting capabilities, high thermal hardness, high curing strength, high carbon yield, and environmental friendliness. PF is important binder for refractory ceramics. In this work, new PF, namely Si/B-modified PF, was prepared through in situ polymerization of boric acid using 25% glutaraldehyde (GA) aqueous solution, n-butanol, and bisphenol A (BPA) as raw materials to synthesize BPA–GA PF. Furthermore, when dimethyldiethoxysilane is introduced into BPA-GA, the modified PF exhibits excellent yield and thermal resistance when an appropriate amount of the modifying element is added. X-ray photoelectron spectroscopy, scanning electron microscopy, and thermogravimetric analysis indicate that the novel Si/B-modified PF possesses superior antioxidant properties and higher yields compared to the original PF. This modified PF has promising applications in bioengineering, aerospace industry, energy storage devices, and other fields. [ABSTRACT FROM AUTHOR]

Gravity forward modeling as a basic tool has been widely used for topography correction and 3D density inversion. The source region is usually discretized into tesseroids (i.e., spherical prisms) to consider the influence of the curvature of planets in global or large-scale problems. Traditional gravity forward modeling methods in spherical coordinates, including the Taylor expansion and Gaussian–Legendre quadrature, are all based on spatial domains, which mostly have low computational efficiency. This study proposes a high-efficiency forward modeling method of gravitational fields in the spherical harmonic domain, in which the gravity anomalies and gradient tensors can be expressed as spherical harmonic synthesis forms of spherical harmonic coefficients of 3D density distribution. A homogeneous spherical shell model is used to test its effectiveness compared with traditional spatial domain methods. It demonstrates that the computational efficiency of the proposed spherical harmonic domain method is improved by four orders of magnitude with a similar level of computational accuracy compared with the optimized 3D GLQ method. The test also shows that the computational time of the proposed method is not affected by the observation height. Finally, the proposed forward method is applied to the topography correction of the Moon. The results show that the gravity response of the topography obtained with our method is close to that of the optimized 3D GLQ method and is also consistent with previous results. [ABSTRACT FROM AUTHOR]

The synthesis of Bisphenol A Glutaraldehyde Phenolic Resin (BPA-GA PF) was carried out under alkaline conditions using Bisphenol, A (BPA) and Glutaraldehyde (GA) as raw materials, with n-butanol serving as the solvent. Based on the aforementioned information, the researchers prepared modified BPA-GA PF resins by incorporating titanium (Ti), silicon (Si), and boron (B) through a polymer derivative method. This process led to the formation of Ti/Si/B-modified PF resins. By manipulating the proportion of elements in the BPA-GA PF, the modified phenolic resin demonstrated improved capacity for design and processing. The characterization of the modified BPA-GA PF involved the analysis of its transformation process and thermal behavior through the utilization of Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric Analysis (TGA). The presence of B, Ti, and Si elements in the system resulted in the formation of Si–O-B and B-O bonds, as determined. The Ti/Si/B -modified PF exhibited a significant increase in yield. Analysis employing X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) revealed that, following high-temperature annealing, the materials underwent a transformation into Ti/Si/B-modified PF with a highly cross-linked network structure. Oxidation experiments conducted under static conditions demonstrated that the Ti/Si/B-modified BPA-GA PF exhibited significantly greater high-temperature resistance compared to the BPA-GA PF. Among the various options, the Ti/Si/B-modified PF material with a Ti/Si ratio of 1:2 exhibited the most superior resistance to high-temperatures. [ABSTRACT FROM AUTHOR]

The gravity anomalies reflect density perturbations at different depths, which control the physical state and dynamics of the lithosphere and sub-lithospheric mantle. However, the gravity effect of the crust masks the mantle signals. In this study, we develop two frameworks (correction with density contrasts and actual densities) to calculate the gravity anomalies generated by the layered crust. We apply the proposed approaches to evaluate the global mantle gravity disturbances based on the new crustal models. Consistent patterns and an increasing linear trend of the mantle gravity disturbances with lithospheric thickness and Vs velocities at 150 km depth are obtained. Our results indicate denser lithospheric roots in most cratons and lighter materials in the oceanic mantle. Furthermore, our gravity map corresponds well to regional geological features, providing new insights into mantle structure and dynamics. Specifically, (1) reduced anomalies associated with the Superior and Rae cratons indicate more depleted roots compared with other cratons of North America. (2) Negative anomalies along the Cordillera (western North America) suggest mass deficits owing to the buoyant hot mantle. (3) Positive anomalies in the Baltic, East European, and Siberian cratons support thick, dense lithosphere with significant density heterogeneities, which could result from thermo-chemical modifications of the cratonic roots. (4) Pronounced positive anomalies correspond to stable blocks, e.g., Arabian Platform, Indian Craton, and Tarim basin, indicating a thick, dense lithosphere. (5) Low anomalies in the active tectonic units and back-arc basins suggest local mantle upwellings. (6) The cold subducting/detached plates may result in the high anomalies observed in the Zagros and Tibet. [ABSTRACT FROM AUTHOR]

Novel Si3N4/PAN/SiZrOCN ceramic aerogel composites, which have excellent wave transmission functions, were prepared through electrospinning, freeze-drying, and high-temperature pyrolysis. Polyvinyl alcohol was used as the aerogel carbon skeleton, polystyrene served as the pore-forming substance, Si3N4/PAN fiber was used as the reinforcement material. The pore size distribution and dielectric properties of the composites were systematically studied at different pyrolysis temperatures. An increase in pyrolysis temperatures led to a decrease in the specific surface area and dielectric constant. Fourier infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction were employed to investigate the polymerization mechanism and ceramic process of the precursor. The Brunauer–Emmett–Teller test revealed that the maximum specific surface area of Si3N4/PAN/SiZrOCN ceramic aerogel composites was 109.261 m2/g, and the average pore size was 4.56 nm when sintered at 600 °C. The dielectric properties test results showed a dielectric constant ranging between 3.1 and 3.7 and a dielectric loss tangent value between 2.6 × 10–3 and 1.6 × 10–2 for the sample. Si3N4/PAN/SiZrOCN ceramic aerogel composites exhibited excellent dielectric properties at room temperature and demonstrated exceptional dielectric stability across different frequency bands (1.8–18.0 GHz), making them a potential high-temperature wave-transmittance material. [ABSTRACT FROM AUTHOR]

Main conclusion: This review provides a direction for crop quality improvement and ideas for further research on the application of CRISPR/Cas9 gene editing technology for crop improvement. Various important crops, such as wheat, rice, soybean and tomato, are among the main sources of food and energy for humans. Breeders have long attempted to improve crop yield and quality through traditional breeding methods such as crossbreeding. However, crop breeding progress has been slow due to the limitations of traditional breeding methods. In recent years, clustered regularly spaced short palindromic repeat (CRISPR)/Cas9 gene editing technology has been continuously developed. And with the refinement of crop genome data, CRISPR/Cas9 technology has enabled significant breakthroughs in editing specific genes of crops due to its accuracy and efficiency. Precise editing of certain key genes in crops by means of CRISPR/Cas9 technology has improved crop quality and yield and has become a popular strategy for many breeders to focus on and adopt. In this paper, the present status and achievements of CRISPR/Cas9 gene technology as applied to the improvement of quality in several crops are reviewed. In addition, the shortcomings, challenges and development prospects of CRISPR/Cas9 gene editing technology are discussed. [ABSTRACT FROM AUTHOR]

Pipeline inspection is important to ensure the safe operation of pipelines. Obtaining the location of an underground pipeline is a prerequisite for most inspection technologies. Existing pipeline location methods can find a pipeline's location, but they require multiple measurements and cannot be used by automatic inspection robots. In this paper, a tunnel magnetoresistance (TMR)-sensor-array-based pipeline location method is proposed to solve this problem. Firstly, a detection probe is designed using a TMR sensor array. It is calibrated by the improved ellipsoid fitting method to measure the magnetic field around the pipeline accurately. Secondly, a relative pipeline-position-locating method is proposed by detecting the phases of the magnetic induction signals at different frequencies. Thirdly, a three-dimensional pipeline location method is proposed. The horizontal and vertical distances and the angle between the pipeline and the probe are calculated by measuring the magnetic induction amplitude. Finally, a simulation model and a test platform are established, and the experimental results illustrate that, by adopting the TMR array, the three-dimensional pipeline location method can locate a pipeline in real time in three dimensions with good accuracy. [ABSTRACT FROM AUTHOR]

Summary: WRKY transcription factors (TFs) are crucial regulators in response to pathogen infection. However, the regulatory mechanisms of WRKY TFs in response to Fusarium oxysporum f. sp. vasinfectum (Fov), the most devastating pathogen of cotton, remain unclear.Here, transcriptome sequencing indicated that the group IIc WRKY TF subfamily was the most important TF subfamily in response to Fov. Gain‐of‐function and loss‐of‐function analyses showed that group IIc WRKY TFs positively regulated cotton resistance to Fov. A series of chromatin immunoprecipitation sequencing, yeast one‐hybrid assay and electrophoresis mobility shift assay experiments indicated that group IIc WRKY TFs directly bound to the promoter of GhMKK2 and regulated its expression.Importantly, a novel mitogen‐activated protein kinase (MAPK) cascade composed of GhMKK2, GhNTF6 and GhMYC2 was identified. The functional analysis indicated that group IIc WRKY TFs induced the GhMKK2‐GhNTF6 pathway to increase resistance to Fov by upregulating the GhMYC2‐mediated expression of several flavonoid biosynthesis‐related genes, which led to flavonoid accumulation.In conclusion, our study demonstrated a novel disease defense mechanism by which the WRKY‐MAPK pathway promotes flavonoid biosynthesis to defend against pathogen infection. This pathway improves our understanding of the interaction mode between WRKY TFs and MAPK cascades in plant immunity and the vital role of plant flavonoids in pathogen defense. [ABSTRACT FROM AUTHOR]

The rapid development of next‐generation portable electronic devices urgently requires dual‐functional materials that possess both efficient heat dissipation and outstanding electromagnetic interference (EMI) shielding performances. In this study, anisotropically oriented carbon films with high thermal conductivity and excellent EMI shielding properties are prepared through an innovative glucose hydrogel‐controllable carbonization method. The horizontal alignment of nanocrystalline graphite results in oriented structures with an extremely high in‐plane thermal conductivity of 439.9 W m−1 K−1, exhibiting a more effective heat‐dissipating capacity on smartphones than their commercial graphite counterparts. Additionally, owing to multiple internal reflections arising from the oriented structures, the films exhibit an EMI shielding effectiveness (SE) of 21.72 dB at an ultrathin thickness of 480 nm in the X‐band and an extraordinarily high absolute shielding effectiveness (SSE/t) of 275 883 dB cm2 g−1, significantly outperforming most of the reported synthetic materials. Furthermore, the flexibility, high mechanical strength, and stability of the films are demonstrated and therefore show promising application prospects. This study offers a facile yet feasible strategy for preparing dual‐functional materials to address the heat emission and EMI problems of advanced electronic devices in a more economical and environmentally friendly manner. [ABSTRACT FROM AUTHOR]

The lunar mascon basins are characterized by high gravity anomalies and thin crust. Study of the density structure beneath the mascon basins can help to understand the origin of these gravity anomalies and infer their formation and evolution. We propose an efficient forward gravity method based on the 3‐D Gauss‐Legendre quadrature (GLQ) and Fast Fourier Transforms combined with the adaptive discretization strategy to ensure high accuracy. The numerical example demonstrates that computational efficiency is increased by about three orders of magnitude compared to the traditional 3D GLQ method. We employ this forward method in a 3‐D inversion of the gravity data derived from the lunar gravity model GL1500E. The inverted results show prominent high‐density structures (namely, mascons) representing significant mantle uplift and thinned crust beneath most impact basins. Marked low‐density rings surround the mascons. Most of the corresponding low‐density anomalies extend from the near‐surface to the Moho, indicating a thick, low‐density crust. Our density model is consistent with the formation processes of mascons that an impact causes collapse of the transient crater and then the shocked mantle drives mantle flow. The low‐density rings surrounding the mascons may stem from the crust thickening following an impact and extensive fracturing of the crustal column. Plain Language Summary: Mascons (i.e., mass concentration) have been found beneath most of the lunar impact basins. Knowledge of their density distribution is vital for understanding of their structure and evolution. The mass excesses in some impact basins extend from the base of the lunar crust to about 60 km depth and correspond to a density anomaly of up to 400 kg/m3. These mass concentrations are usually surrounded by a ring of low‐density crust. These features are consistent with the hypothesis that the mascons were formed after an asteroid impact and the upwelling mantle material filling the impact crater. This high‐density material produces the mass excess under the impact basins, while the broken crustal material forms the thick low‐density crust around the mascons. Key Points: A highly efficient forward modeling method for gravity calculations is proposed and used in inversionProminent high‐density structures represent significant mantle uplift and thinned crust beneath most of the impact basinsNegative density anomalies around the mascons form outer rings which may be associated with crustal thickening [ABSTRACT FROM AUTHOR]

Key message: We reviewed recent advances related to RIN4, including its involvement in the immune process through posttranslational modifications, PM H+-ATPase activity regulation, interaction with EXO70 and identification of RIN4-associated NLR proteins. RPM1-interacting protein 4 (RIN4) is a conserved plant immunity regulator that has been extensively studied and can be modified by pathogenic effector proteins. RIN4 plays an important role in both PTI and ETI. In this article, we review the functions of the two conserved NOI domains of RIN4, the C-terminal cysteine residues required for membrane localization and the sites targeted and modified by effector proteins during plant immunity. In addition, we discuss the effect of RIN4 on the stomatal virulence of pathogens via the regulation of PM H+-ATPase activity, which is involved in the immune process through interactions with the exocyst subunit EXO70, and progress in the identification of RIN4-related R proteins in multiple species. This review provides new insights enhancing the current understanding of the immune function of RIN4. [ABSTRACT FROM AUTHOR]

Background and aims: Mycorrhizosphere is the interface between roots and soil where a myriad of microorganisms mediate plant growth, nutrient acquisition and tolerance to biotic and abiotic stress, and result in driving ecosystem biogeochemical cycling. Understanding the complexity and dynamics of mycorrhizosphere and its ecology and evolution are critical to enhancing forest productivity and ecosystem functioning, especially in high latitude temperate or high altitude alpine forests. However, the fungal community compositions and their driving ecological mechanisms of mycorrhizosphere during forest restoration are poorly documented. Methods: In this study, we simultaneously examined the ectomycorrhizal (EM) and rhizospheric fungal communities of two dominant host tree species (Abies faxoniana and Betula albosinensis) in subalpine forest communities with distinct forest restoration stages (30- vs. 60-year) after clear-cutting. Illumina MiSeq sequencing of internal transcribed spacer 2 (ITS2) sequences was adopted. Results: A total of 1222 EM and 5880 rhizosphere fungal operational taxonomic units (OTUs) were obtained at a 97% sequence similarity level, which were mainly dominated by Basidiomycota. Host identity and forest restoration stage had no significant effects on fungal species richness of both EM and rhizospheric fungi. However, the community assembly of EM and rhizospheric fungi was significantly different during forest restoration, with opposite patterns shown on ectomycorrhizae and rhizosphere. The EM fungal community assembly was significantly affected by host identity, stand age and population dynamic, while the rhizosphere fungal community was significantly structured by combinations of host trees biomass, soil properties and spatial distance. Conclusions: Our data provide important insights that community assembly of EM and rhizosphere fungi may respond idiosyncratically during forest restoration, which will help us deeper understanding forest succession, stability and ecosystem functioning on the Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Elevational variations in the growing environment and sex differences in individuals drive the diversification of photosynthetic capacity of plants. However, photosynthetic response of dioecious plants to elevation gradients and the mechanisms that cause these responses are poorly understood. We measured foliar gas exchange, chlorophyll fluorescence and nitrogen allocations of male and female Seabuckthorn (Hippophae rhamnoides L.) at the elevation of 1900–3700 m above sea level (a.s.l.) on the eastern Qinghai-Tibetan Plateau, China. Male and female plants showed increased leaf photosynthetic capacity at higher elevation generally with no sex-specific difference. Photosynthetic photon flux density-saturated photosynthesis (A sat) was limited mostly by diffusional components (77 ± 1%), whereas biochemical components contributed minor limitations (22 ± 1%). Mesophyll conductance (g m) played an essential role in A sat variation, accounting for 40 ± 2% of the total photosynthetic limitations and had a significant positive correlation with A sat. Leaf nitrogen allocations to Rubisco (P R) and bioenergetics (P B) in the photosynthetic apparatus were major drivers for variations in photosynthetic nitrogen-use efficiency. The increase of these resource uptake capacities enables H. rhamnoides to maintain a high level of carbon assimilation and function efficiently to cope with the harsh conditions and shorter growing season at higher elevation. [ABSTRACT FROM AUTHOR]

The polyandrous mating system of honeybees (Apis mellifera L.) has garnered widespread attention. Long-lived honeybee queens only mate early in maturation, and the sperm obtained from the aerial mating is stored in the spermatheca. The maintenance of sperm viability in the spermatheca is an intriguing and complex process. However, the key physiological and biochemical adaptations underlying the long-term storage of sperm remain unclear. Analysis of the metabolite profile could help better understand the biology of the spermatheca and offer insights into the breeding and conservation of honeybees and even pest control strategies. Here, the changes in metabolites in the spermatheca were quantified between virgin queens and new-laying queens (with stored sperm) via liquid chromatography–mass spectrometry. Compared with virgin queens, changes occurred in lipids and lipid-like molecules, including fatty acyls and glycerophospholipids (GPL), prenol lipids, and sterol lipids, during storage of sperm in new-laying honeybee queens. Furthermore, the metabolic pathways that were enriched with the differentially expressed metabolites were identified and included GPL metabolism, biosynthesis of amino acids, and the mTOR signaling pathway. The likely roles of the pathways in the maintenance and protection of sperm are discussed. The study identifies key metabolites and pathways in the complex interplay of substances that contribute to the long-term storage of sperm and ultimately reproductive success of honeybee queens. [ABSTRACT FROM AUTHOR]

N-Terminal asparagine amidohydrolase is a component of the ubiquitin-dependent N-end rule pathway of protein degradation that has been implicated in a variety of physiological functions, including the sensing of heme, oxygen, nitric oxide, selective elimination of misfolded proteins and the repair of DNA. We identified the Apis cerana cerana N-terminal asparagine amidohydrolase (AccNtan1) gene from A. cerana cerana and investigated its role in oxidation resistance. Multiple sequence alignments and phylogenetic analysis revealed that N-terminal asparagine amidohydrolase is highly conserved in insect species. Quantitative real-time polymerase chain reaction analysis indicated that the expression levels of AccNtan1 were significantly lower in the wing, honey sac and abdomen than in other tissues and were significantly higher in early stages of development, including the larva, prepupa and pink-eyed pupa stages, than in later stages. We further observed that AccNtan1 expression was induced by several environmental stressors, including aberrant temperature, H2O2, UV, heavy metals and pesticides. Moreover, a bacteriostatic assay suggested that overexpression of AccNtan1 enhances the resistance of bacteria to oxidative stress. In addition, knockdown of AccNtan1 using RNA interference significantly affected the expression levels of most antioxidant genes and the activity levels of several antioxidant enzymes. Thus, we hypothesize that AccNtan1 plays important roles in environmental stress responses and antioxidative processes. [ABSTRACT FROM AUTHOR]

We use the improved Parker‐Oldenburg's formulas that include a reference depth into the exponential term and employ the Gauss‐fast Fourier transform method to determine Moho depth beneath the Tibetan Plateau. The synthetic models demonstrate that the improved Parker's formula has high accuracy with the maximum absolute error less than 0.25 mGal compared to the analytical solution. Two inversion parameters, that is, the reference depth and the density contrast, are essential for the Moho estimation based on the gravity field, and they need to be determined in advance to obtain correct results. Therefore, the Moho estimates derived from existing seismic studies are used to reduce the nonuniqueness of the gravity inversion and to determine these parameters by searching for the maximum correlation between the gravity‐inverted and seismic‐derived Moho depths. Another critical issue is to remove beforehand the gravity effects of other factors, which affect the observed gravity field besides Moho variations. In addition to the topography, the gravity effects of the sedimentary layer and crystalline crust are removed based on existing crustal models, while the upper mantle impact is determined based on the seismic tomography model. The inversion results show that the Moho structure under the Tibetan plateau is very complex with the depths varying from about 30–40 km in the surrounding basins (e.g., Ganges basin, Sichuan basin, and Tarim basin) to 60–80 km within the plateau. This considerable difference up to 40 km on the Moho depth reveals the substantial uplift and thickening of the crust in the Tibetan Plateau. Furthermore, two visible "Moho depression belts" are observed within the plateau with the maximum Moho deepening along the Indus‐Tsangpo Suture and along the northern margin of Tibet bounding the Tarim basin with the relatively shallow Moho in central Tibet between them. The southern "belt" is likely formed in compressional environment, where the Indian plate underthrusts northward beneath the Tibetan Plateau, while the northern one could be formed by the southward underthrust of the Asian lithosphere beneath Tibet. Key Points: The improved Parker's formula guarantees high accuracyGravity effect of the crustal and upper mantle density variations is removedNew Moho beneath Tibet well corresponds to seismic data [ABSTRACT FROM AUTHOR]

An efficient forward modeling algorithm for calculation of gravitational fields in spherical coordinates is developed for 3‐D large‐scale gravity inversion problems. The 3‐D Gauss‐Legendre quadrature (GLQ) is used to calculate the gravitational fields of mass distributions discretized into tesseroids. Equivalence relations in the kernel matrix of the forward modeling are exploited to decrease storage and computation time. The numerical tests demonstrate that the computation time of the proposed algorithm is reduced by approximately 2 orders of magnitude, and the memory requirement is reduced by N′λ times compared with the traditional GLQ method, where N′λ is the number of the model elements in the longitudinal direction. These significant improvements in computational efficiency and storage make it possible to calculate and store the dense Jacobian matrix in 3‐D large‐scale gravity inversions. The equivalence relations can be applied to the Taylor series method or combined with the adaptive discretization to ensure high accuracy. To further illustrate the capability of the algorithm, we present a regional synthetic example. The inverted results show density distributions consistent with the actual model. The computation took about 6.3 hr and 0.88 GB of memory compared with about a dozen days and 245.86 GB for the traditional 3‐D GLQ method. Finally, the proposed algorithm is applied to the gravity field derived from the latest lunar gravity model GL1500E. Three‐dimensional density distributions of the Imbrium and Serenitatis basins are obtained, and high‐density bodies are found at the depths 10–60 km, likely indicating a significant uplift of the high‐density mantle beneath the two mascon basins. Key Points: An efficient forward modeling algorithm with kernel matrix equivalence is developedComputation time and memory requirement of the algorithm are significantly reducedThree‐dimensional density distributions of the Imbrium and Serenitatis basins are obtained [ABSTRACT FROM AUTHOR]

Carbon nanosheet-coated micron zirconium diboride particles were achieved by an atmospheric chemical vapor deposition in the presence of methane gas without catalyst. The microstructures and carbon structure for the novel particles were characterized by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. In addition, the growth process of hybrid particles was analyzed by thermodynamic theory. The results showed that zirconium diboride particles were coated by carbon nanosheets uniformly. The carbon nanosheets/zirconium diboride particles were employed to fabricate ceramic composite using spark plasma sintering process. The fracture toughness of the composite was improved up to 5.9 MPa·m0.5 with only 0.9 wt% of carbon nanosheets, which was 40.9% higher than that of the composite without carbon nanosheets. The toughening mechanisms were mainly known as carbon nanosheets crack bridging and pulling out which lead to the formation of crack deflection in the novel composite. [ABSTRACT FROM AUTHOR]

A continuous three-year observation (from May 2008 to April 2011) was conducted to characterize the spatial variation of dissolved inorganic nitrogen (DIN) deposition at eight main forest ecosystems along the north-south transect of eastern China (NSTEC). The results show that both throughfall DIN deposition and bulk DIN deposition increase from north to south along the NSTEC. Throughfall DIN deposition varies greatly from 2.7 kg N/(ha·yr) to 33.0 kg N/(ha·yr), with an average of 10.6 kg N/(ha·yr), and bulk DIN deposition ranges from 4.1 kg N/(ha·yr) to 25.4 kg N/(ha·yr), with an average of 9.8 kg N/(ha·yr). NH-N is the dominant form of DIN deposition at most sampling sites. Additionally, the spatial variation of DIN deposition is controlled mainly by precipitation. Moreover, in the northern part of the NSTEC, bulk DIN deposition is 17% higher than throughfall DIN deposition, whereas the trend is opposite in the southern part of the NSTEC. The results demonstrate that DIN deposition would likely threaten the forest ecosystems along the NSTEC, compared with the critical loads (CL) of N deposition, and DIN deposition in this region is mostly controlled by agricultural activities rather than industrial activities or transportation. [ABSTRACT FROM AUTHOR]

Abstract: Background and objective: Procaterol, a selective, short‐acting beta‐2 adrenoceptor agonist, is effective in treating ‘classical’ asthma, but its efficacy for cough‐variant asthma (CVA) is unknown. We evaluated the efficacy and safety of procaterol combined with budesonide for CVA. Methods: A prospective, randomized, double‐blind, placebo‐controlled, multicenter trial in China was conducted. One hundred and fifty‐nine patients diagnosed with CVA (aged 18–75 years) were randomly divided into two groups to receive twice daily for 8 weeks, inhaled budesonide 100 μg plus either oral procaterol 25 μg or placebo. Primary and secondary efficacy variables were cough symptom severity scores and Leicester Cough Questionnaire (LCQ) life quality scores. Adverse events were also assessed. Results: The budesonide/placebo and budesonide/procaterol groups contained 80 and 78 participants (one excluded for later diagnosis of eosinophilic bronchitis), respectively, with similar baseline characteristics. Daily cough score declined during treatment in both groups and was lower in the budesonide/procaterol group at 8 (0.44 vs 0.73) and 10 (0.36 vs 0.69) weeks (P < 0.05). Compared with the budesonide/placebo group, the proportion of patients with a reduction of 3 points or greater (66% vs 42%) and that of patients scoring 0 points (63% vs 51%) was higher in the budesonide/procaterol group for daily cough scores (P < 0.05). At 8 weeks, LCQ score improvement was superior in the budesonide/procaterol group (38.94 ± 19.24 vs 32.71 ± 18.92; P < 0.05). Conclusion: Procaterol combined with budesonide was well tolerated and effective at improving cough symptoms and quality of life in patients with CVA. [ABSTRACT FROM AUTHOR]

Symmetric reduction-responsive amphiphilic comblike copolymers mid-disulfide-functionalized comblike copolymers with alternating copolymer comprised of styrenic unit and N-(2-hydroxyethyl) maleimide (HEMI) unit (poly(St-alt-HEMI)) backbones and alternating PEG and PCL side chains (S-CP(PEG- alt-PCL)) with poly(St- alt-HEMI) backbones and alternating poly(ε-caprolactone) (PCL) and poly(ethylene glycol) (PEG) side chains were synthesized and used as nanocarriers for in vitro release of doxorubicin. The target copolymers with predetermined molecular weight and narrow molecular weight distribution ( Mw/ Mn = 1.15-1.20) were synthesized by reversible addition-fragmentation chain transfer (RAFT) copolymerization of vinylbenzyl-terminated PEG and N-(2-hydroxyethyl) maleimide mediated by a disulfide-functionalized RAFT agent S-CPDB, and followed by ring-opening polymerization of ε-caprolactone. When compared with linear block copolymer comprised of poly(ethylene glycol) (PEG) and poly(ϵ-caprolactone) (PCL) segments (PEG- b-PCL) copolymers, comblike copolymers with similar PCL contents usually exhibited decreased crystallization temperature, melting temperature, and degree of crystallinity, indicating the significant influence of copolymer architecture on physicochemical properties. Dynamic light scattering measurements revealed that comblike copolymers were liable to self-assemble into aggregates involving vesicles and micelles with average diameter in the range of 56-226 nm and particle size distribution ranging between 0.07 and 0.20. In contrast to linear copolymer aggregates, comblike copolymer aggregates with similar compositions were of improved storage stability and enhanced drug-loading efficiency. In vitro drug release confirmed the disulfide-linked comblike copolymer aggregates could rapidly release the encapsulated drug when triggered by 10 mM DL-dithiothreitol. These reduction-sensitive, biocompatible, and biodegradable aggregates have a potential as controlled delivery vehicles. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

An automated chamber system was used to study how soil respiration (R S) differed with stand age (SA), altitude (AL), and forest type (FT), in subtropical China. From 2006 to 2008, measurements of soil-surface CO2 efflux and associated environmental factors were made in an evergreen broad-leaved forest (EB), and five aged Chinese fir [Cunninghamia lanceolata Hook.] plantations (CF), and three altitudinal Moso bamboo [Phyllostachys pubescens Mazel ex J. Houz.] plantations (MB), in Dagangshan mountain range, Jiangxi Province. Multivariate analysis of covariance with soil temperature (T) and soil water content (SWC) as the covariates showed that FT and AL as the independent factors had a significant effect on R S (P<0.01, P<0.05, respectively). The R S in the CF differed significantly from EB and MB (P<0.001), but not between EB and MB. The R S was positively correlated with T, and responded to changes in SWC at higher Ts. The correlation between R S and SWC was improved when the R S was normalized to 10°C. Annual mean R S differed significantly with SA and were ranked in the order (from high to low) of 21-25, 26-35, 11-20, >36, and 1-10 years. The conclusion of this study is that T, SWC, AL, FT, and SA all have significant effects on Rs in subtropical China. [ABSTRACT FROM AUTHOR]

The plant mitogen-activated protein kinase (MAPK) cascade plays an important role in mediating responses to biotic and abiotic stresses and is the main pathway through which extracellular stimuli are transduced intracellularly as signals. Our previous research showed that the GhMKK6-GhMPK4 cascade signaling pathway plays an important role in cotton immunity. To further analyze the role and regulatory mechanism of the GhMKK6-GhMPK4 cascade signaling pathway in cotton resistance to Fusarium wilt, we functionally analyzed GhMPK4. Our results show that silencing GhMPK4 reduces cotton tolerance to Fusarium wilt and reduces the expression of several resistance genes. Further experiments revealed that GhMPK4 is similar to GhMKK6, both of whose overexpression cause unfavorable cotton immune response characteristics. By using a yeast two-hybrid screening library and performing a bioinformatics analysis, we screened and identified a negative regulator of the MAPK kinase-protein phosphatase AP2C1. Through the functional analysis of AP2C1, it was found that, after being silenced, GhAP2C1 increased resistance to Fusarium wilt, but GhAP2C1 overexpression caused sensitivity to Fusarium wilt. These findings show that GhAP2C1 interacts together with GhMPK4 to regulate the immune response of cotton to Fusarium oxysporum, which provides important data for functionally analyzing and studying the feedback regulatory mechanism of the MAPK cascade and helps to clarify the regulatory mechanism through which the MAPK cascade acts in response to pathogens. [ABSTRACT FROM AUTHOR]

Evaluation of forest ecosystem services is a hot topic, both in China and at abroad, but it has not yet obtained a consistency of evaluation indicator systems and evaluation methods. Under the framework of evaluation criteria to be implemented for forest ecosystem services, years of consecutive observation data from Long Term Ecological Research Stations affiliated to Chinese Forest Ecosystem Research Network (CFERN), forest resource inventory and public data were applied to carry out a detailed and dynamic evaluation on the physical quantity and value of ecosystem services of Chinese pine forests in China. The results showed that the above services had the total value and unit value of 1144.9640 billion (1.1449640×1012) RMB and 52.074 thousand RMB per hectare per year, respectively during the 9th Five-year Plan (1996–2000), and of 1190.5461 billion RMB and 52.101 thousand RMB per hectare per year, respectively, during the 10th Five-year Plan (2001–2005). For Chinese pine forests, water conservation was 40.40 hundred million cubic meters annually, soil conservation was 67 million tons and C fixation 9 million tons annually, production of healthful negative ions was 1.96×1020, absorption of SO2 was 5.02 hundred million kilograms and dust-catching was 759.10 hundred million kilograms. Among the 15 provinces of China with Chinese pine forests, the biggest beneficiary from ecosystem services was Liaoning Province; while Hunan Province was the smallest beneficiary between the 9th Five-year Plan. [ABSTRACT FROM AUTHOR]