Genome-wide analysis of CCCH zinc finger family in Arabidopsis and rice

<p>Abstract</p> <p>Background</p> <p>Genes in the CCCH family encode zinc finger proteins containing the motif with three cysteines and one histidine residues. They have been known to play important roles in RNA processing as RNA-binding proteins in animals. To date, few plant CCCH proteins have been studied functionally.</p> <p>Results</p> <p>In this study, a comprehensive computational analysis identified 68 and 67 CCCH family genes in Arabidopsis and rice, respectively. A complete overview of this gene family in Arabidopsis was presented, including the gene structures, phylogeny, protein motifs, and chromosome locations. In addition, a comparative analysis between these genes in Arabidopsis and rice was performed. These results revealed that the CCCH families in Arabidopsis and rice were divided into 11 and 8 subfamilies, respectively. The gene duplication contributed to the expansion of the CCCH gene family in Arabidopsis genome. Expression studies indicated that CCCH proteins exhibit a variety of expression patterns, suggesting diverse functions. Finally, evolutionary analysis showed that one subfamily is higher plant specific. The expression profile indicated that most members of this subfamily are regulated by abiotic or biotic stresses, suggesting that they could have an effective role in stress tolerance.</p> <p>Conclusion</p> <p>Our comparative genomics analysis of CCCH genes and encoded proteins in two model plant species provides the first step towards the functional dissection of this emerging family of potential RNA-binding proteins.</p

Responses of calcareous sand foundations to variations of groundwater table and applied loads

The long-term settlement of calcareous sand foundations caused by daily periodic fluctuations has become a significant geological hazard, but effective monitoring tools to capture the deformation profiles are still rarely reported. In this study, a laboratory model test and an in situ monitoring test were conducted. An optical frequency domain reflectometer (OFDR) with high spatial resolution (1 mm) and high accuracy (±10-6) was used to record the soil strain responses to groundwater table and varied loads. The results indicated that the fiber-optic measurements can accurately locate the swelling and compressive zones. During the loading process, the interlock between calcareous sand particles was detected, which increased the internal friction angle of soil. The foundation deformation above the sliding surface was dominated by compression, and the soil was continuously compressed beneath the sliding surface. After 26–48 h, calcareous sand swelling occurred gradually above the water table, which was primarily dependent on capillary water. The swelling of the soil beneath the groundwater table was completed rapidly within less than 2 h. When the groundwater table and load remain constant, the compression creep behavior can be described by the Yasong-Wang model with R2 = 0.993. The daily periodically varying in situ deformation of calcareous sand primarily occurs between the highest and lowest groundwater tables, i.e. 4.2–6.2 m deep. The tuff interlayers with poor water absorption capacity do not swell or compress, but they produce compressive strain under the influence of deformed calcareous sand layers

Genetically engineered magnetic nanocages for cancer magneto-catalytic theranostics

磁热疗法是一种利用磁热敏剂在磁场中把磁能转换为热能以杀死肿瘤的新型癌症治疗方法，并已成功应用于临床。但是，目前临床所用磁热敏剂的磁-热转换效率低而使得治疗剂量过大，从而给病人带来潜在的副作用，因此大大限制了磁热疗法的广泛应用。该研究利用基因工程和仿生矿化技术制备出具有优异磁-热转化能力及纳米酶催化性能的磁性蛋白纳米笼（eMIONs），成功克服了临床磁热疗法中磁热敏剂低效的瓶颈，为新一代磁热敏剂的研发提供新的思路。该研究工作在刘刚教授指导下完成，博士生张阳为文章第一作者。【Abstract】The clinical applications of magnetic hyperthermia therapy (MHT) have been largely hindered by the poor magnetic-to-thermal conversion efficiency of MHT agents. Herein, we develop a facile and efficient strategy for engineering encapsulin-produced magnetic iron oxide nanocomposites (eMIONs) via a green biomineralization procedure. We demonstrate that eMIONs have excellent magnetic saturation and remnant magnetization properties, featuring superior magnetic-to-thermal conversion efficiency with an ultrahigh specific absorption rate of 2390 W/g to overcome the critical issues of MHT. We also show that eMIONs act as a nanozyme and have enhanced catalase-like activity in the presence of an alternative magnetic field, leading to tumor angiogenesis inhibition with a corresponding sharp decrease in the expression of HIF-1α. The inherent excellent magnetic-heat capability, coupled with catalysis-triggered tumor suppression, allows eMIONs to provide an MRI-guided magneto-catalytic combination therapy, which may open up a new avenue for bench-to-bed translational research of MHT.This work was supported by the Major State Basic Research Development Program of China (2017YFA0205201), the National Natural Science Foundation of China (81925019, 81422023, 81603015, 81871404, and U1705281), the Fundamental Research Funds for the Central Universities (20720190088 and 20720200019), and the Program for New Century Excellent Talents in University, China (NCET-13-0502). We acknowledge Jingru Huang and Baoying Xie from Central Laboratory in School of Medicine, Xiamen University, for assistance with inductively coupled plasma experiments and data analysis. 研究工作得到了科技部重大专项课题、973课题、国家自然科学基金委杰出青年基金等项目的支持

PwHAP5, a CCAAT-binding transcription factor, interacts with PwFKBP12 and plays a role in pollen tube growth orientation in Picea wilsonii

The HAP complex occurs in many eukaryotic organisms and is involved in multiple physiological processes. Here it was found that in Picea wilsonii, HAP5 (PwHAP5), a putative CCAAT-binding transcription factor gene, is involved in pollen tube development and control of tube orientation. Quantitative real-time reverse transcription-PCR showed that PwHAP5 transcripts were expressed strongly in germinating pollen and could be induced by Ca2+. Overexpression of PwHAP5 in pollen altered pollen tube orientation, whereas the tube with PwHAP5RNAi showed normal growth without diminishing pollen tube growth. Furthermore, PwFKBP12, which encodes an FK506-binding protein (FKBP) was screened and a bimolecular fluorescence complementation assay performed to confirm the interaction of PwHAP5 and PwFKBP12 in vivo. Transient expression of PwFKBP12 in pollen showed normal pollen tube growth, whereas the tube with PwFKBP12RNAi bent. The phenotype of overexpression of HAP5 on pollen tube was restored by FKBP12. Altogether, our study supported the role of HAP5 in pollen tube development and orientation regulation and identified FKBP12 as a novel partner to interact with HAP5 involved in the process

Predicting the Remaining Service Life of Civil Airport Runway considering Reliability and Damage Accumulation

Based on the MEPDG method, the operation process of MEPDG was analyzed and the MEPDG correction method applied to the remaining life prediction of airport pavement was obtained. According to the theory of structural reliability, the performance function of airport pavement was obtained based on the limit state equation represented by flexural stress. Considering the characteristics of airport cement concrete pavement design, the calculation formula of the number of allowable load actions was obtained based on reliability by NCHRP126 fatigue equation without considering the temperature stress when the flexural fatigue strength of pavement plate cement concrete was less than 1.25 times of the design strength. Based on the actual situation of local civil airport runways in Henan Province, the proposed MEPDG correction method was used to analyze the flexural stress of the actual operating airport runway pavement at 95% reliability level based on the mechanical numerical model of airport runway, and the number of allowable load actions of three aircraft models was obtained. Given the impact of pass-to-coverage ratio P/C, the cumulative damage factor CDF of the major aircraft models was calculated; the annual average growth rate of different aircraft models in the airport pavement evaluation stage was obtained based on the trend extension method. According to the predicted average annual cumulative damage, the remaining life of pavement was predicted. Compared with the actual conditions of the airport, the remaining life predicted in this paper was consistent with the actual life, which verifies the effect of the prediction of the remaining life of airport runway considering the impact of reliability and damage accumulation

Deep Multi-Layer Perception Based Terrain Classification for Planetary Exploration Rovers

Accurate classification and identification of the detected terrain is the basis for the long-distance patrol mission of the planetary rover. But terrain measurement based on vision and radar is subject to conditions such as light changes and dust storms. In this paper, under the premise of not increasing the sensor load of the existing rover, a terrain classification and recognition method based on vibration is proposed. Firstly, the time-frequency domain transformation of vibration information is realized by fast Fourier transform (FFT), and the characteristic representation of vibration information is given. Secondly, a deep neural network based on multi-layer perception is designed to realize classification of different terrains. Finally, combined with the Jackal unmanned vehicle platform, the XQ unmanned vehicle platform, and the vibration sensor, the terrain classification comparison test based on five different terrains was completed. The results show that the proposed algorithm has higher classification accuracy, and different platforms and running speeds have certain influence on the terrain classification at the same time, which provides support for subsequent practical applications

Numerical Investigation of Earth Berm Effects on Prefabricated Recyclable Supporting Structure in Circular Excavations

The prefabricated recyclable supporting structure (PRSS) is an innovative support system that integrates a steel skeleton with polymer waterproof technology. Earth berms are extensively adopted to support the PRSS, but there is limited understanding on the factors influencing their behavior in circular excavations. In this paper, a numerical model is first validated with a case history in Henan, China. Afterwards, the geometric parameters of the earth berms, including the height (H), the top width (B1), and the bottom width (B2), on the behavior of the PRSS, are investigated. It is shown that, by increasing the height, top width and bottom width of earth berms, the lateral deflections, and bending moments of supporting piles, as well as the ground surface settlements, tend to decrease. However, the reduction effect of these parameters diminishes as well. Moreover, the raised effective formation level considering the effect of the earth berms on stability and deformation analyses is discussed. The factor of the safety of the excavation is almost doubled when axisymmetric conditions are considered compared to plane strain conditions. In deformation analysis, the raised effective formation level increases with the height of the earth berms until a steady value is reached