Wheat TaMYB1A Negatively Regulates the Phenylpropanoid Pathway and Plant Height / 中国生物化学与分子生物学报

The phenylpropanoid pathway is one of the important pathways for synthesizing plant secondary metabolites, which can produce lignin, flavonoid, and sinapoylmalate. These compounds can not only affect the plant growth, development, and stress response, but also be used to produce perfume, pesticide, dye, medicine, feed, and biomass energy. R2R3-MYBs play important roles in regulating plant secondary metabolism, organ development, and in responding to environmental stresses. Wheat (Triticum aestivum L.) is an important food crop, but lots of straw will be produced accompanied by grain yields. Therefore, elucidating the function and regulatory mechanism of R2R3 MYBs of wheat is crucial for the effective utilization of the wheat straw. RT-PCR results showed that TaMYB1A was highly expressed in the wheat stems, and the GFP-TaMYB1A fusion protein was mainly localized in the nucleus of the N. benthamiana epidermal cells. TaMYB1A has transcriptional repressive activity in yeast cells. In this study, TaMYB1A-overexpressed transgenic Arabidopsis lines were generated to elucidate the effect of overexpression of TaMYB1A on the biosynthesis of lignin and flavonoid. Our results suggested that overexpression of TaMYB1A inhibited the plant height (P < 0. 05) and decreased the lignin (P < 0. 05) and flavonoid (P < 0. 05) biosynthesis of the transgenic Arabidopsis plants significantly. TaMYB1A could bind to the promoters of the Arabidopsis At4CL1, AtC4H, AtC3H, and AtCHS as well as the wheat Ta4CL1 and TaC4H1 revealed by yeast one-hybrid (Y1H) assasy, the transcriptional repressive effect of TaMYB1A on At4CL1, AtC4H, AtC3H, and AtCHS was confirmed by dual-luciferase reporter systems and also on Ta4CL1 and TaC4H1 by a genetic approach. Gene chip and quantitative RT-PCR (qRT-PCR) results showed that overexpression of TaMYB1A down-regulated the expression of most of the key genes involved in the phenylpropanoid metabolism and decreased the 4CL activity (P < 0. 05) of the transgenic Arabidopsis plants significantly. As suggested above, the wheat TaMYB1A belongs to the subgroup 4 R2R3 MYB transcription factors. TaMYB1A could bind to the promoters of the key genes involved in phenylpropanoid metabolism, repress their expression and negatively regulate the phenylpropanoid metabolism pathway and plant height.

The Prediction for COVID-19 Outbreak in China by using the Concept of Term Structure for the Turning Period.

This study aims to develop a general framework for predicting the duration of the Turning Period (or Turning Phase) for the COVID-19 outbreak in China that started in late December 2019 from Wuhan. A new concept called the Term Structure for Turning Period (instead of Turning Point) is used for this study, and the framework, implemented into an individual SEIR (iSEIR) model, has enabled a timely prediction of the turning period when applied to Wuhan's COVID-19 epidemic, and provided the opportunity for relevant authorities to take appropriate and timely actions to successfully control the epidemic. By using the observed daily COVID-19 cases in Wuhan from January 23, 2020 to February 6 (and February 10), 2020 as inputs to the framework it allowed us to generate the trajectory of COVID-19 dynamics and to predict that the Turning Period of COVID-19 outbreak in Wuhan would arrive within one week after February 14. This prediction turned out to be timely and accurate, which has provided adequate time for the government, hospitals and related sectors and services to meet peak demand and to prepare aftermath planning. We want to emphasize that emergency risk management entails the implementation of an emergency plan, where timing the Turning Period is key to express a clear timeline for effective actions. Our study confirms the observed effectiveness of Wuhan's Lockdown and Isolation control program imposed since January 23, 2020 to the middle of March, 2020 and resulted in swiftly flattened epidemic curve, and Wuhan's success offers an exemplary lesson for the world to learn in combating COVID-19 pandemic.

Fabric Defect Detection Based on Illumination Correction and Visual Salient Features.

Aiming at the influence of uneven illumination on fabric feature extraction and the limitations of traditional frequency-based visual saliency algorithms, we propose a fabric defect detection method based on the combination of illumination correction and visual salient features-(1) Construct a multi-scale side window box (MS-BOX) filter to extract the illumination component of the image, then use the constructed two-dimensional gamma correction function to perform illumination correction on the image in the global angle, and finally enhance the local contrast of the image in the local angle; (2) Use the L0 gradient minimization method to remove the background texture of fabric images and highlight the defects; (3) Represent the fabric image as a quaternion image, where each pixel in the image is represented by a quaternion consisting of color, intensity and edge characteristics. The two-dimensional fractional Fourier transform (2D-FRFT) is used to obtain the saliency map of the quaternion image. Experiments show that our method has a higher overall recall rate for defect detection of star-patterned, box-patterned, and dot-patterned fabrics, and the overall recall-precision effect is better than other existing methods.

Experimental Study of Coaxial Cylinder Dielectric Barrier Discharge in Ar/NH3 Mixtures under the Atmosphere-Pressure.

An atmosphere-pressure Dielectric Barrier Discharge in Ar/NH3 mixtures between cylinder electrodes is studied by Optical Emission Spectroscopy and the main particles of atmosphere-pressure Ar/NH3 DBD plasma are NH, N, N+, N2, Ar, H(α) and OH. NH is decomposition products of NH3, and NH(c 1π) and NH(A 3π) are two kinds of excited-state neutral particles and produced by penning ionization of Ar* and NH3. The nitrogen active atom is detected at 674.5 nm which may provide the experimental foundation for the synthesis of ε-Fe3N ferroparticles by the atmosphere-pressure Ar/NH3 DBD plasma. The intensities of main particles are analyzed at different NH3 flow rate and applied voltage peak-peak value. The results show that the spectral line intensities of various particles increase with the rise of the applied voltage peak-peak value at the same NH3 flow rate, and first increase and then decrease with the increase of the NH3 flow rate at the same applied voltage peak-peak value. The applied voltage peak-peak value being kept constant, the spectral line intensity of nitrogen active atom first increases and then decreases with the increase of the NH3 flow rate. When NH3 flow rate is 20 mL x min(-1), the spectral line intensity of nitrogen active atom reaches a maximum at the same applied voltage peak-peak value. The spectral line intensity of nitrogen active atom decreases gradually with increasing the applied voltage peak-peak value at the same NH3 flow rate and it is mainly because of the translation of discharge mode from multi-pulse APGD to filamentary discharge in the atmosphere-pressure Ar/NH3 DBD. The microdischarge channels overlap and the microdischarges affect each other in multi-pulse APGD; hence the increasing rate of the spectral line intensity is quicker in multi-pulse APGD than in filamentary discharge with increasing the applied voltage peak-peak value. When the applied voltage peak-peak value is up from 4 600 to 6 400 V, the single-pulse and two-pulse APGD mode which are two kinds of homogeneous DBD mode are found in the atmosphere-pressure Ar/NH3 DBD and the increasing rate of the spectral line intensity is quicker in multi-pulse APGD than in filamentary discharge which is beneficial to synthesize ε-Fe3N ferroparticles.

Optimization of radiological protection of patients undergoing digital radiography / 中华放射医学与防护杂志

Objective To identify the necessity to carry out optimization procedure in routine digital radiography (DR) by evaluating changes of patient radiation dose and image waste ratio before and after optimization.Methods Two hundred patients with near-standard body build were enrolled in the study.Half of them undertook routine examination,and the others undertook the examination with bestlyoptimized protocol.The dose-area product (DAP) and entrance surface dose (ESD) were recorded.The image waste ratios in 2 groups were calculated and the reasons for image waste were analyzed.The radiation dose and image waste ratio before and after optimization were compared.Results The ESD,DAP and image waste ratio in bestly-optimized radiography were significantly lower than those in non-optimized radiography (z =9.31,16.22,P＜0.05; x2 =36.5,P ＜ 0.05).Conclusion Using the bestlyoptimized digital radiography,the patient radiation dose and image waste ratio are effectively reduced.

[Study on mechanism of ionic liquid for methane plasma conversion using spectra method].

C6MIMBF4, C6MIMCF3 COO and C6MIMHSO4 were introduced into a direct current discharge plasma system respectively for methane conversion. The kinds of active species and relative intensity of spectral peaks were detected via online spectrum diagnosis technique of optical emission spectroscopy. Mechanism of ionic liquid for methane conversion in gas-liquid plasma was investigated. The results showed that a spatially and temporally stable gas-liquid interface was obtained in ionic liquid incorporated plasma system. With introduction of ionic liquid, methane conversion and C2 hydrocarbons yields increased. The C2 hydrocarbon selectivity greatly increased when C6MIMCF3 COO and C6MIMBF4 were introduced to the plasma, and decreased when C6MIMHSO4 was used. Active species like C, C2, C3, CH and H were detected in gas-liquid plasma system of methane discharge. Compared with the absence of ionic liquid in the plasma system, the relative intensity of spectral peaks of most active species increased when ionic liquid was introduced into the plasma system. 1H NMR results showed that the structure of ionic liquid kept stable during plasma discharge progress. Those indicated that ionic liquid could improve the plasma discharge intensity. At the same time, ionic liquid showed good catalytic activity in gas-liquid surface reaction.

Factors influencing the choice of atrial septal occluder for transcatheter closure of secundum atrial septal defects / 中华心血管病杂志

<p><b>OBJECTIVE</b>To analyze factors influencing the choice of atrial septal occluder (ASO) for transcatheter closure of patients with secundum atrial septal defect (ASD).</p><p><b>METHODS</b>A total of 1114 ASD patients [388 males, aged from 2 to 75 years, mean age (26.3 +/- 17.0) years] were enrolled. Patients were divided to adult (> 14 years, mean 34.4 years, n = 779) and child (< or = 14 years, mean 7.3 years, n = 335) groups. ASD size in different ultrasound cross-sections was determined by transthoracic echocardiography (TTE). ASO size was chosen on the basis of the maximum diameter of the defect (MD). Defect-shapes and rim lengths of ASD, the difference choice of ASO in the two groups were compared.</p><p><b>RESULTS</b>MD of the defects ranged from 5 to 40 mm [mean (19.7 +/- 7.8) mm]. ASD was successfully occluded in 1085 out of 1114 patients (97.4%). Occluder size ranged from 6 to 46 mm [mean (25.8 +/- 8.9) mm] and the difference between occluder size and MD ranged from 2 to 10 mm [mean (6.1 +/- 3.4) mm, ASO/MD ratio 1.3:1]. Though the diameter of the defect was similar between the 2 groups, the size of occluder was significantly larger in adult group than that in child group (ASO/MD ratio 1.1 - 1.6:1 vs. 1.2 - 1.8:1, P < 0.05). MD was significantly correlated with ASO in both groups (r = 0.911 and r = 0.944 in adults and child groups, respectively, all P < 0.01). The size and increment of the occluder used in patients with deficient anterior rims was significantly bigger than patients with sufficient anterior rims (P < 0.01).</p><p><b>CONCLUSION</b>The maximum diameter of the defect was the major determinant for selecting occluder size and choice of occluder size was also influenced by patient age, defect-shape and defect rim for transcatheter closure of secundum ASD.</p>

L-type calcium channel blocker suppresses calcineurin signal pathway and development of right ventricular hypertrophy.

BACKGROUND AND PURPOSE: Many studies have shown that L-type calcium channel blockers can prevent and treat right ventricular hypertrophy (RVH). In order to identify the mechanism, we investigated the role of the calcineurin signal pathway in the progression of RVH induced by chronic hypoxia and the effects of an L-type calcium channel blocker on the pathway. METHODS: Rats were allocated to 1 of 3 groups (n=10 for each): chronic hypoxia group, amlodipine treatment group (30 mg/kg/day, administered via gavage); and control group. Rats in the amlodipine treatment group and the chronic hypoxia group were exposed to normobaric chronic hypoxia (9.5%-10.5% oxygen). We investigated the changes of right ventricle (RV) to left ventricle (LV) and interventricular septum (S) weight ratio [RV/(LV+S)], RV to body weight (BW) ratio (RV/BW), calcineurin A beta (CnAbeta) mRNA levels, cardiac myosin heavy chain beta (beta-MHC) mRNA levels and protein expression of CnAbeta, nuclear factor 3 of activated T cell (NFAT3), and beta-MHC. RESULTS: After 21 days, RV/(LV+S) and RV/BW were significantly higher in the chronic hypoxia group than in the control group and the amlodipine group (p<0.01). The expression of CnAbeta mRNA and protein, NFAT3 protein, beta-MHC mRNA and protein in RV of the chronic hypoxia group was higher than that of the control group and the amlodipine treatment group (p<0.01). CONCLUSIONS: The calcineurin signal pathway plays a critical role in the progression of RVH induced by chronic hypoxia. L-type calcium channel blockade suppresses the development of RVH by inhibiting this pathway.