A Single Amino Acid Substitution in MIL1 Leads to Activation of Programmed Cell Death and Defense Responses in Rice

Lesion mimic mutants are an ideal model system for elucidating the molecular mechanisms of programmed cell death and defense responses in rice. In this study, we identified a lesion mimic mutant termed miner infection like 1-1 (mil1-1). The mil1-1 exhibited lesions on the leaves during development, and the chloroplasts of mil1-1 leaves were disrupted. Reactive oxygen species were found to accumulate in mil1-1 leaves. Cell death and DNA fragmentation were observed in mil1-1 leaves, indicating that the cells in the spots of mil1-1 leaves experienced programmed cell death. Most agronomic traits decreased in mil1-1, suggesting that the growth retardation in mil1-1 caused reduced per-plant grain yield. However, the mutation of MIL1 activated the expression of pathogen response genes and enhanced resistance to bacterial blight. The MIL1 gene was cloned using the positional cloning approach. A missense mutation 751 bp downstream of ATG was found in mil1-1. The defects of mil1-1 were able to be rescued by delivering a wild-type MIL1 gene into mil1-1. MIL1 encoded hydroperoxide lyase 3 (OsHPL3), and the expression of OsHPL3 was induced via hormone and abiotic stresses. Our findings provide insights into the roles of MIL1 in regulating programmed cell death, development, yield, and defense responses in rice.     

Property and Stability of Astaxanthin Emulsion Based on Pickering Emulsion Templating with Zein and Sodium Alginate as Stabilizer

Astaxanthin loaded Pickering emulsion with zein/sodium alginate (SA) as a stabilizer (named as APEs) was developed, and its structure and stability were characterized. The encapsulation efficiency of astaxanthin (Asta) in APEs was up to 86.7 ± 3.8%, with a mean particle size of 4.763 μm. Freeze-dried APEs showed particles stacked together under scanning electronic microscope; whereas dispersed spherical nanoparticles were observed in APEs dilution under transmission electron microscope images. Confocal laser scanning microscope images indicated that zein particles loaded with Asta were aggregated with SA coating. X-ray diffraction patterns and Fourier transform infrared spectra results showed that intermolecular hydrogen bonding, electrostatic attraction and hydrophobic effect were involved in APEs formation. APEs demonstrated non-Newtonian shear-thinning behavior and fit well to the Cross model. Compared to bare Asta extract, APEs maintained high Asta retention and antioxidant activity when heated from 50 to 10 °C. APEs showed different stability at pH (3.0–11.0) and Na⁺, K⁺, Ca²⁺, Cu²⁺ and Fe²⁺ conditions by visual, zeta potential and polydispersity index measurements. Additionally, the first order kinetics fit well to describe APEs degradation at pH 3.0 to 9.0, Na⁺, and K⁺ conditions. Our results suggest the potential application of Asta-loaded Pickering emulsion in food systems as a fortified additive.     

Experiences of Trauma and DNA Methylation Profiles among African American Mothers and Children

Potentially traumatic experiences have been associated with chronic diseases. Epigenetic mechanisms, including DNA methylation (DNAm), have been proposed as an explanation for this association. We examined the association of experiences of trauma with epigenome-wide DNAm among African American mothers (n = 236) and their children aged 3–5 years (n = 232; N = 500), using the Life Events Checklist-5 (LEC) and Traumatic Events Screening Inventory—Parent Report Revised (TESI-PRR). We identified no DNAm sites significantly associated with potentially traumatic experience scores in mothers. One CpG site on the ENOX1 gene was methylome-wide-significant in children (FDR-corrected q-value = 0.05) from the TESI-PRR. This protein-coding gene is associated with mental illness, including unipolar depression, bipolar, and schizophrenia. Future research should further examine the associations between childhood trauma, DNAm, and health outcomes among this understudied and high-risk group. Findings from such longitudinal research may inform clinical and translational approaches to prevent adverse health outcomes associated with epigenetic changes.     

三维测头探测误差的评定准则及高精度评定方法研究

在对三维测头探测误差进行分析的基础上,参照球度误差的定义,给出了探测误差的4种评定准则及相应评定算法.对一组测量数据,用Powell寻优方法按最小包容区域准则对探测误差进行了评定,并与按最小二乘准则的评定结果进行了比较,分析及计算结果表明,采用最小包容区域准则与方法,消除了传统探测误差评定方法存在的原理误差,提高了检定准确度.     

手工具的人性化设计研究

从人的因素出发,依据人机工程学对手工具的设计进行分析和研究,并从工业设计的角度提出如何从手工具材料、造型、色彩等方面作出改进,进一步优化手工具人性化设计.     

基于FGCM的冠脉OCT图像纤维斑块分割算法

冠脉OCT图像中的纤维斑块精确分割对于冠心病的诊断具有重大意义。针对模糊C均值算法邻域信息和空间信息利用率低,在分割具有弱边界的纤维化斑块过程中容易产生过分割的情况,提出了基于自定义窗口的邻域信息项和具有全局约束项G的FCM算法,即FGCM算法。首先,对OCT图像进行预处理,去除噪声。然后,采用自定义窗口获取像素强度的邻域信息,并将邻域信息和创造性提出的全局约束项G添加到FCM算法,使用FGCM算法分割纤维化斑块。最后,采用数学形态学方法作为后处理操作平滑斑块边界。通过对具有典型纤维化斑块特征的8个病例进行测试,与医生手动标记纤维化斑块(金标准)和其他文献的算法进行对比,测试结果显示所提算法分割精确度进一步提高,达到90%,能够进一步对血管狭窄程度进行定量分析,辅助医生制定诊断方案。     

基于质谱分析的航天器工质原位检漏技术研究

航天器推进系统、热控系统、环控系统及流体回路系统有严格的泄漏指标要求,基于质谱分析的检漏方法存在本底信号干扰及重复性较差等难点,建立了工质原位检漏方法的理论模型,分析了质谱室直接进样与分流进样的特点,确定了分流进样的技术方案;通过试验,获得了大气环境取样条件下质谱室工作压力与本底信号的关系;同时,通过氦气、氪气、氙气等标准漏孔重复性试验获得了工质气体校准系数与本底信号的关系,并验证了系统检漏灵敏度满足航天器检漏要求。     

Changes in the Expression and Functional Activities of C-X-C Motif Chemokine Ligand 13 (CXCL13) in Hyperplastic Prostate

Background: C-X-C motif chemokine ligand 13 (CXCL13), a member of the CXC subtype in chemokine superfamily, affects numerous biological processes of various types of cells and the progress of a great number of clinical diseases. The purpose of the current study was to reveal the internal mechanism between CXCL13 and benign prostatic hyperplasia (BPH). Methods: Human serum, prostate tissues and human prostate cell lines (BPH-1, WPMY-1) were utilized. The effect of recombinant human CXCL13 (rHuCXCL13) protein and the influences of the knockdown/overexpression of CXCL13 on two cell lines were studied. Rescue experiments by anti-CXCR5 were also conducted. In vivo, rHuCXCL13 was injected into the ventral prostate of rats. Additionally, a tissue microarray of hyperplastic prostate tissues was constructed to analyze the correlations between CXCL13 and clinical parameters. Results: CXCL13 was highly expressed in the prostate tissues and upregulated in the BPH group. It was observed that CXCL13 modulated cell proliferation, apoptosis, and the epithelial–mesenchymal transition (EMT) through CXCR5 via AKT and the ERK1/2 pathway in BPH-1, while it contributed to inflammation and fibrosis through CXCR5 via the STAT3 pathway in WPMY-1. In vivo, rHuCXCL13 induced the development of rat BPH. Additionally, CXCL13 was positively correlated with the prostate volume and total prostate specific antigen. Conclusions: Our novel data demonstrated that CXCL13 modulated cell proliferation, cell cycle, the EMT of epithelial cells, and induced the fibrosis of prostatic stromal cells via a variety of inflammatory factors, suggesting that CXCL13 might be rediscovered as a potential therapeutic target for the treatment of BPH.     

光纤激光相干合成研究进展

近年来,以激光大气传输为应用背景的光束相干合成技术被广泛研究,而关于该项技术在空间光通信中的应用研究却不多。事实上,基于光束相干合成的多孔径接收天线结构可有效缓解大气湍流影响,提高空间激光通信系统的性能。本论文简要介绍了中国科学院自适应光学重点实验室面向激光大气传输应用的激光组束传输与湍流校正技术研究近况;重点介绍关于多孔径接收空间光通信系统中的光纤相干合成研究进展,主要包括基于3 dB光纤耦合器的相干合成和基于光纤偏振合束器的相干偏振合成两种方法,在空间光通信系统中具有极大的潜在应用。