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Litter decomposition is a key process of the carbon cycle in terrestrial and aquatic ecosystems. The dominant conceptual model of litter decomposition assumes that environmental conditions, litter traits, and decomposer composition control litter decomposition in a decreasing order, yet whether this hierarchical model applies to both invasive and native plant species is unknown. Here, by comparing a widespread invasive plant and its native counterpart in Chinese coastal saltmarshes, we aimed to examine whether the hierarchy of factors controlling litter decomposition varies with plant species in the face of plant invasions. Leaf litter of invasive Spartina alterniflora and native Phragmites australis was collected across an 18° latitudinal range to capture wide variation in litter traits. These leaf litter samples were transported to three saltmarsh sites of different latitudes and were incubated in litterbags varying in mesh size (0.1, 2, and 5 mm) to manipulate decomposer composition. After 90-day incubation, we found a parallel latitudinal pattern in leaf litter decomposition rate (k) between S. alterniflora and P. australis regardless of saltmarsh site and mesh size. Nonetheless, the k value of S. alterniflora was 2.2-fold higher than that of P. australis. Moreover, there was a shift in the hierarchy of factors controlling k values between S. alterniflora and P. australis: environmental conditions (climate and soil) dominated other factors in P. australis, whereas litter traits contributed more than environmental conditions in S. alterniflora. Overall, our findings show that leaf litter decomposition and its dominant controlling factors across broad geographical ranges can vary with plant invasions, having important implications for managing invasive plants in the context of conserving coastal blue carbon.凋落物分解是陆地和水域生态系统碳循环的关键过程。凋落物分解模型通常认为控制凋落物分解速率最重要的驱动因素依次为环境条件、凋落物性状和分解者组成。然而这一凋落物分解层级模型的适用性是否在入侵植物和土著植物间具有差异尚不清楚。本研究通过比较中国滨海盐沼中广泛分布的入侵植物互花米草和土著植物芦苇, 探究控制植物凋落物分解的驱动因子层级关系是否因物种而异。本研究跨18°纬度采集了两种植物的叶片凋落物以获得较大变异的凋落物性状, 通过选择三个不同纬度的分解地(东营、上海、漳州)以控制分解环境, 同时选择三种不同孔径(0.1、2和5 mm)的凋落物袋以控制分解者类群。经过90天的野外分解实验, 结果表明:(1)互花米草叶片凋落物分解速率是芦苇叶片凋落物的2.2倍; (2)无论分解地和凋落物袋网目大小, 互花米草与芦苇的叶片凋落物分解速率均随凋落物来源地纬度的升高而增加; (3)控制凋落物分解的因子层级关系因物种而异, 环境条件主导控制芦苇凋落叶分解, 而凋落物性状在控制互花米草凋落叶分解中起主要作用。综上, 本研究表明在大地理尺度上植物入侵会改变凋落物分解速率及其主导控制因子, 这对保护滨海蓝碳生态系统目标下的入侵植物管理具有重要启示。.

Constructing a conductive carbon-based artificial interphase layer (AIL) to inhibit dendritic formation and side reaction plays a pivotal role in achieving longevous Zn anodes. Distinct from the previously reported carbonaceous overlayers with singular dopants and thick foreign coatings, a new type of N/O co-doped carbon skin with ultrathin feature (i.e., 20 nm thickness) is developed via the direct chemical vapor deposition growth over Zn foil. Throughout fine-tuning the growth conditions, mosaic nanocrystalline graphene can be obtained, which is proven crucial to enable the orientational deposition along Zn (002), thereby inducing a planar Zn texture. Moreover, the abundant heteroatoms help reduce the solvation energy and accelerate the reaction kinetics. As a result, dendrite growth, hydrogen evolution, and side reactions are concurrently mitigated. Symmetric cell harvests durable electrochemical cycling of 3040 h at 1.0 mA cm

Photodynamic therapy (PDT) affects vascular barrier function and thus increases vessel permeability. This phenomenon may be exploited to facilitate targeted drug delivery and may lead to a new clinical application of photodynamic therapy. Here, we investigate the role of leukocyte recruitment for PDT-induced vascular permeabilization. STUDY DESIGN/MATERIAL AND METHODS: Fluorescein isothiocyanate dextran (FITC-D, 2,000 kDa) was injected intravenously 120 minutes after focal PDT on striated muscle in nude mice bearing dorsal skinfold chambers (Visudyne® 800 µg/kg, fluence rate 300 mW/cm2 , light dose of 200 J/cm2). Leukocyte interaction with endothelial cells was inhibited by antibodies functionally blocking adhesion molecules ("MABS-PDT" group, n = 5); control animals had PDT but no antibody injection (group "PDT", n = 7). By intravital microscopy, we monitored leukocyte rolling and sticking in real-time before, 90 and 180 minutes after PDT. The extravasation of FITC-D from striated muscle vessels into the interstitial space was determined in vivo during 45 minutes to assess treatment-induced alterations of vascular permeability.

Inverse analysis of time domain refl ectometry (TDR) waveform in the frequency domain is important in measuring complex dielectric permittivity of soils. However, for widely used probes designed as impedance mismatching and nonseparable connection between probe head and coaxial cable, none of the available models can be used for the inverse analysis. The objective of this study was to derive a model which is applicable for this specifi c type of probes. A two-section (probe head and probe rods) model was derived from the full model of Feng et al. (1999) by reducing its complexity on the basis of the matching design of cable tester and coaxial cable. The model was validated by comparison of the measured spectra of properly terminated coaxial cable with the theoretical values, and the accuracy of the model was studied by the comparison of the estimated complex dielectric permittivity of ethanol by the model with those measured by the network analyzer method. This model was applied to a silt loam soil under different levels of water content and electrical conductivity (EC). The results showed that the two-section model was applicable for this specifi c type of probes to measure complex dielectric permittivity at low frequency range. The lowest frequency of 30 MHz was used to estimate soil complex dielectric permittivity. The real parts of the estimated soil dielectric permittivity were close to the apparent dielectric permittivity determined by travel time analysis (TTA). The soil bulk EC calculated from the imaginary parts of the estimated soil dielectric permittivity was close to the measured values.

The traditional thin dielectric sheet approximation (TDS) method models the electromagnetic scattering by thin dielectric sheet using surface integral equation. In this approximation, only the tangential current within the dielectric sheet is considered, and the vertical component is ignored. This article proposes a method that uses the volume integral equation solution to predict the vertical volume current and hence to improve the overall solution accuracy. The formulation is based on the hybrid surface (SIE) and volume integration equation (VIE) in which, the thin dielectric is modeled with SIE, and the thin layers are modeled by VIE. It is shown that the inclusion of the vertical current component does not increase memory and solution time. Numerical examples will be provided to demonstrate the effectiveness of this approach. © Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1978–1982, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23518

In practical applications, frequency-selective surfaces (FSSs) are finite, and sometimes even curved. In this paper, we present a hybrid volume-surface integral-equation approach to analyze the transmission and reflection characteristics of finite and curved FFS structures. The hybrid integral equations are established using the surface- and volume-equivalent principles. This approach has two advantages. One is the capability of modeling arbitrarily shaped FSS structures in detail, the other one allows us to easily apply the multilevel fast multiple algorithm to speed up the solution process. The scattering characteristics and frequency responses of several FSSs are analyzed. The simulation results show that for a finite-sized FSS, reducing the radius of curvature causes amplitude variation, frequency shift, and bandwidth change in the reflection and transmission responses. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 107–112, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20738

The rewarming process of cryopreserved organs using microwave technology is analyzed by numerical simulation. The FDTD (finite-difference time-domain) method is applied to calculate the electromagnetic field in a real microwave rewarming system, composed by a cylindrical resonant cavity, an antenna source, and a frozen rabbit-kidney phantom with temperature-dependent properties. The efficiency of the FDTD codes is improved by nonuniform grid techniques and parallel algorithms. Meanwhile, an apparent specific-heat method is introduced in the temperature-field calculation. Coupling the solutions of the two fields is realized by a formerly developed algorithm. The numerical results show that in the rewarming process of the rabbit kidney phantom, the warming rate can reach 300°–500°C/min, which may prevent devitrification, but the maximum temperature difference in the sample (18 mm in radius) can reach 15°C at the end, which may cause severe thermal stress. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 201–205, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20945

This paper discusses a special imaging reconstruction problem in which the object to be reconstructed resides in a homogeneous media but consists of a known part and an unknown part. The known part is combined with the homogeneous background media to form an inhomogeneous media. The dielectric permittivity profiles are reconstructed for the unknown part using the Born iteration (BI) method. Numerical examples demonstrate that this modified BI algorithm has faster convergence and higher accuracy than the regular BI method. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 91–95, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10684

Three-dimensional indoor radio-wave propagation is accurately modeled by solving the volume electric-field integral equation (VEFIE). The integral equation is discretized by the method of moments (MoM), in which the building walls, ceilings, floors, as well as any internal obstacles are represented by a collection of small volumetric cells. This discretization is capable of modeling a 3-D room structure to fine details. The solution to the MoM matrix equation is facilitated by the multilevel fast multipole algorithm (MLFMA), which significantly reduces memory requirements and CPU time. Numerical examples are shown to demonstrate the accuracy of the solution and the capability of modeling dielectric structures of nearly realistic sizes. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 168–175, 2001.

In the solution of an integral equation using the conjugate gradient (CG) method, the most expensive part is the matrix-vector multiplication, requiring O(N2) floating-point operations. The fast multipole method (FMM) reduced the operation to O(N15). In this article we apply a multilevel algorithm to this problem and show that the complexity of a matrix-vector multiplication is proportional to N (log(N))2. © 1994 John Wiley & Sons, Inc.

We develop a new algorithm to expedite the matrix-vector multiplication in using the conjugate gradient method to solve the linear algebraic equation of scattering by a cluster of particles. We compare this method of solving the scattering problem with two other methods. One is our previously developed method, called recursive aggregate T-matrix method. The second one is the direct use of the conjugate gradient method. Our new method is shown to have reduced computational complexity as well as memory requirement compared to the use of the conjugate gradient directly to solve the linear algebraic equation of scattering. © 1993 John Wiley & Sons, Inc.

A new algorithm is proposed to solve the volume integral equation whereby the scatterer is first divided into N subscatterers. Smaller problems are nested within larger problems using the Huygens equivalence principle. The resultant algorithm has reduced computational complexity whose CPU time is proportional to N1.5. © 1993 John Wiley & sons, Inc.

A truncated, nonuniform, finite array of strips does not have a closed-form solution. Using translational symmetry, a recursive algorithm that calculates the scattering solution with N log2 N computational complexity is described. The current distribution for the Hz polarization shows small-length-scale oscillations not present in the Ez polarization.