A New Correction to the Rytov Approximation for Strongly Scattering Lossy Media

We propose a correction to the conventional Rytov approximation (RA) and investigate its performance for predicting wave scattering under strong scattering conditions. An important motivation for the correction and investigation is to help in the development of better models for inverse scattering. The correction is based upon incorporating the high frequency theory of inhomogeneous wave propagation for lossy media into the RA formulation. We denote the technique as the extended Rytov approximation for lossy media (xRA-LM). xRA-LM significantly improves upon existing non-iterative linear scattering approximations such as RA and the Born approximation (BA) by providing a validity range for the permittivity of the objects of up to 50 times greater than RA. We demonstrate the technique by providing results for predicting wave scattering from piece-wise homogeneous scatterers in a two-dimensional (2D) region. Numerical investigation of the performance of xRA-LM for solving direct problem show that xRA-LM can accurately predict wave scattering by electrically large, low-loss scatterers with high complex permittivity ($\epsilon_r> 50+5j$). To the best of our knowledge, this is the first non-iterative, linear approximate wave scattering model which has a large validity range in terms of both permittivity and electrical size

Peer effect, political competition and eco-efficiency: evidence from city-level data in China

This study examines the impacts of political competition on eco-efficiency. We first develop a theoretical model in which local government officials compete against each other to maximise their own political score. We find that after an initial stage of decline, eco-efficiency eventually turns upwards, once environmental performance becomes a meaningful component of local government officials’ annual assessment. Eco-efficiency also exhibits a pattern of convergence. Lastly, the level of political competition is found to be negatively correlated with eco-efficiency. For the empirical analysis, we use a data envelopment analysis (DEA) model to compute the eco-efficiency level for 191 Chinese cities from 2003 to 2015. Our empirical evidence presents a ‘U’-shape pattern in the trend of eco-efficiency and identifies two peer effects that work in opposite directions: the incentivising effect arising from higher performing neighbours, and the disincentivising effect when a city outperforms its competitors. Both peer effects lead to convergence in eco-efficiency, and our spatial econometric modeling analysis suggests that the net peer effect is significantly positive. We also find evidence of political competition reducing eco-efficiency, as predicted in the theoretical model. Our findings are robust to alternative measures of eco-efficiency.</p

DRE2 associates with chromatin and some auxin responsive genes.

(A-B) Detection of DRE2 in cytoplasmic, nucleoplasmic and chromatin-associated fractions by Western blot. DRE2-HA fusion protein was detected using an anti-HA antibody. DRE2-GFP fusion protein was detected using an anti-GFP antibody. HSP90 and histone H3 were detected as markers for cytoplasmic proteins and chromatin proteins, respectively. AGO1 was detected as markers for proteins present in all the fractions. (C) Immunostaining results showing the nuclear distribution of DRE2. DRE2-HA in the pDRE2::DRE2-HA transgenic plants was stained with an anti-HA antibody and an Alexa Fluor 488-conjugated secondary antibody (green). DNA was stained with DAPI (blue). (D) ChIP-qPCR results showing the enrichment of DRE2-GFP at four auxin responsive genes. (E) Relative expression levels of the indicated genes in the indicated genotypes as determined by RT-qPCR. Data are presented as mean ± SD of four technical replicates. Asterisks indicate two-tailed Student’s t-test, *P < 0.05, **P < 0.01.</p

Data_Sheet_1_The Interplay of Rogue and Clustered Ryanodine Receptors Regulates Ca2+ Waves in Cardiac Myocytes.docx

<p>Ca²⁺ waves in cardiac myocytes can lead to arrhythmias owing to delayed after-depolarisations. Based on Ca²⁺ regulation from the junctional sarcoplasmic reticulum (JSR), a mathematical model was developed to investigate the interplay of clustered and rogue RyRs on Ca²⁺ waves. The model successfully reproduces Ca²⁺ waves in cardiac myocytes, which are in agreement with experimental results. A new wave propagation mode of “spark-diffusion-quark-spark” is put forward. It is found that rogue RyRs greatly increase the initiation of Ca²⁺ sparks, further contribute to the formation and propagation of Ca²⁺ waves when the free Ca²⁺ concentration in JSR lumen ([Ca²⁺]_lumen) is higher than a threshold value of 0.7 mM. Computational results show an exponential increase in the velocity of Ca²⁺ waves with [Ca²⁺]_lumen. In addition, more CRUs of rogue RyRs and Ca²⁺ release from rogue RyRs result in higher velocity and amplitude of Ca²⁺ waves. Distance between CRUs significantly affects the velocity of Ca²⁺ waves, but not the amplitude. This work could improve understanding the mechanism of Ca²⁺ waves in cardiac myocytes.</p

The linker region of DRE2 coordinates protein-protein interactions in the CIA pathway.

(A-B) Interactions of DRE2, DRE2Δ6, DRE2-3 and DRE2Δ75 with TAH18, NBP35 and GRXS17 as determined by Y2H assays. Yeast cells harboring different fusion protein combinations (listed at the left) in pGBK-T7 (BD) and pGAD-T7 (AD) vectors were plated on medium lacking Leu, Trp (SD-TL), medium lacking Leu, Trp and His (SD-TLH) and medium lacking Leu, Trp, His and Ade (SD-TLHA) (A) or SD-TLH medium with 1 mM 3AT (B).</p

Generation of <i>dre2</i> hypomorphic mutants using the CRISPR/Cas9 system.

(A) CRISPR/Cas9-induced deletions in dre2-3 and dre2-4. The sgRNA-3 targeting sequence is highlighted in red and the PAM site is underlined. Exons are in upper case letters and introns in lower case. (B) The dre2-3 mutation causes a deletion of nine amino acids. (C) The dre2-4 mutation causes a splicing defect of DRE2 pre-mRNA. RT-PCR shows that the splicing variants of DRE2 mRNA in dre2-4. The positions of primers for RT-PCR are indicated by blue arrows in S1F Fig. (D) Summary of the splicing variants of DRE2 mRNA in dre2-4. (E) Relative expression levels of DRE2 in the indicated genotypes as determined by RT-qPCR. Data are presented as mean ± SD of four technical replicates. Asterisks indicate two-tailed Student’s t-test, *P S1D Fig. (F) In-gel activities of AO in Col-0 and dre2 mutants. Equal amounts of protein (400 μg) extracted from seedlings were separated on nondenaturing PA gels and stained using synthetic aldehydes (1-naphthaldehyde) as substrates. Coomassie brilliant blue staining shows equal loading. The positions of the three bands, AO1, AO2, and AO3, are indicated with arrows.</p

The <i>dre2</i> mutants have accumulation of DNA damage and constitutive activation of DNA damage response.

(A) Typical comet images of nuclei from 21-day-old leaves of Col-0, dre2-3, dre2-4 and met18-2. DNA damage was expressed as the ratio of the signal intensity of a comet tail versus that of the entire nucleus. (B) Frequency distribution of different grades of DNA damage in Col-0, dre2-3, dre2-4 and met18-2. At least 200 comets were counted for each genotype. (C) Relative expression levels of the indicated genes in the indicated genotypes as determined by RT-qPCR. Data are presented as mean ± SD of four technical replicates. Asterisks indicate two-tailed Student’s t-test, *P dre2 mutants either with or without MMS treatment. Results from the second biological replicate are shown in S4 Fig. (D) Short root phenotype of the dre2 mutants. Images of 7-day-old Col-0, dre2-3, dre2-4 and 35S::DRE2/dre2-4 grown on vertical 1/2 MS plates were taken. (E) Statistic analysis of primary root lengths of 7-day-old Col-0, dre2-3, dre2-4 and 35S::DRE2/dre2-4 seedlings. Mean ± SD, n = 10; Asterisks indicate two-tailed Student’s t-test, *P < 0.05, **P < 0.01.</p

Dysfunction of <i>DRE2</i> causes genome-wide DNA hypermethylation.

(A) Venn diagram showing the numbers of hyper-DMRs that either overlap between or are unique in dre2-4 and ros1-4. Boxplots showing the distribution and the average CG, CHG, or CHH methylation levels calculated from hyper-DMRs in the respective subgroups. Dark horizontal line, median; edges of boxes, 25th (bottom) and 75th (top) percentiles; whiskers, minimum and maximum percentage of DNA methylation. (B) Heat-map showing the methylation levels of dre2-4-associated hyper-DMRs in Col-0, dre2-4, met18-2 and ros1-4. The color key is presented at right. Light yellow indicates low methylation and black indicates high methylation. (C) Locus-specific bisulfite sequencing results showing the DNA methylation levels of the ROS1 promoter in different genotypes. (D) Relative expression levels of ROS1 in the indicated genotypes as determined by RT-qPCR. Asterisks indicate two-tailed Student’s t-test, *P S5D Fig.</p

DRE2 is involved in auxin response.

(A) Biological processes associated with downregulated genes in dre2-4. (B) Relative expression levels of CIA pathway genes after 10 μM IAA treatment. The expression level of MET18 at 0 h was set as 1. Data are presented as mean ± SD of four technical replicates. (C) Primary and lateral root phenotypes of 9-day-old Col-0, dre2-3, dre2-4 and met18-2 without or with the application of 10 μM IAA. (D) Statistical analysis of primary root length (upper) and lateral root numbers (lower) of Col-0, dre2-3, dre2-4 and met18-2 seedlings. Mean ± SD, n ≥ 20; Asterisks indicate two-tailed Student’s t-test, *P < 0.05, **P < 0.01.</p

Excited State Localization and Delocalization of Internal Charge Transfer in Branched Push−Pull Chromophores Studied by Single-Molecule Spectroscopy

Excited State Localization and Delocalization of Internal Charge Transfer in Branched Push−Pull Chromophores Studied by Single-Molecule Spectroscop