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To understand the relationship between the damage mechanism of sapphire and the anisotropic characteristic of its crystal structure, in-situ scratch tests under the confocal laser scanning microscope (CLSM) were performed along different directions of C-plane sapphire wafer. The relation between in-situ images and normal/lateral forces was established. Craters in front of the contact region (CR) between the indenter and the material, and subsurface special cracks separated from CR were observed. As the scratch direction changed, these special cracks and craters initiated and propagated on the left front, front, and right front of the CR, respectively. The scratch phenomena in different scratch directions exhibited triple symmetric characteristic around the c-axis. The probability of slip/twinning activation and the theoretical stress field in front of the indenter were calculated to investigate the fracture mechanism of sapphire. Craters and those special cracks appeared in the region with the highest probability of rhombohedral twinning and basal twinning activation, respectively. According to the theoretical stress field, the material ahead of the indenter axis was separated into regions I and II. Craters in front of the CR and those special cracks separated from the CR appeared in these two regions, respectively.

Micro/nano hierarchical structures could endow materials with various surface functions. However, the multilayer and multiscale characteristics of micro/nano hierarchical structures bring difficulties for their one step and controllable fabrication. Accordingly, based on tip-based fabrication techniques, this study proposed a micro-amplitude vibration-assisted scratching method by introducing a periodic backward displacement into the conventional scratching process, which enabled the synchronous creation of the microscale V-groove and nanoscale ripples, i.e. a typical micro/nano hierarchical structure. The experiments and finite element modeling were employed to explore the formation process and mechanism of the micro/nano hierarchical structures. Being different from conventional cutting, this method was mainly based on the plow mechanism, and it could accurately replicate the shape of the indenter on the material surface. The microscale V-groove was formed due to the scratching action, and the nanoscale ripple was formed due to the extrusion action of the indenter on the microscale V-groove’s surface. Furthermore, the relationships between the processing parameters and the dimensions of the micro/nano hierarchical structures were established through experiments, and optimized processing parameters were determined to achieve regular micro/nano hierarchical structures. By this method, complex patterns constructed by various micro/nano hierarchical structures were fabricated on both flat and curved surfaces, achieving diverse surface structural colors.

Undifferentiated carcinoma with osteoclast-like giant cells of the pancreas (UCOGCP) is a rare pancreatic tumor that accounts for less than 1% of all pancreatic malignancies. The characteristic pathological manifestation of UCOGCP is the presence of osteoclast-like giant cells (OGCs) distributed among pleomorphic undifferentiated tumor cells. UCOGCP can occur either alone or in association with other types of pancreatic tumors. At present, there is no unified consensus or guideline for the diagnosis and treatment of UCOGCP, and most of the literature are individual case reports. With the accumulation in the number of clinical cases and the development of precision medicine technology, the understanding of UCOGCP is also deepening. Researchers have begun to recognize that UCOGCP is a pancreatic tumor with distinctive clinical and molecular characteristics. In this review, we focus on the latest research status and future exploration directions in the diagnosis, treatment, and prognosis of UCOGCP.

【Objective】By measuring and analyzing the physical characteristics of the basal stems of rice, the relationship between these traits and the stem breaking resistance was explored, and the core traits affecting the basal stem breaking resistance of rice were identified, providing a theoretical basis for the breeding of rice lodging-resistant varieties.【Method】The study analyzed the lodging resistance-related agronomic traits, including plant height, single plant bending resistance, basal internode breaking resistance, and stem structure, of the rice variety Yuehesimiao, the lodging-susceptible variety Xiangyaxiangzhan, and Yuehesimiao × Xiangyaxiangzhan F2 segregation populations. The influence of each trait on lodging resistance of rice was evaluated by correlation coefficient.【Result】There are significant differences in lodging resistance between the two varieties of Yuehesimiao and Xiangyaxiangzhan. The N2 (second internode from the base) breaking resistance (16.58 N), N2 wall thickness (1.02 mm), N2 filling degree (0.19 g/cm), and N2 stem diameter (6.21 mm) of Yuehesimiao are significantly larger than those of Xiangyaxiangzhan (N2 breaking resistance: 9.93 N, N2 wall thickness: 0.66 mm, N2 filling degree: 0.11 g/cm, N2 stem diameter: 4.60 mm). The N2 breaking resistance, N2 length, N2 stem diameter, stem wall thickness, fresh weight and filling degree of the F2 population show continuous distribution and are controlled by polygenes. The correlation analysis results of the F2 population show that, N2 breaking resistance is positively correlated with plant height (r=0.18), N2 breaking resistance is significantly positively correlated with N2 wall thickness (r=0.75**). N2 breaking resistance is significantly positively correlated with N2 filling degree (r=0.67*). N2 breaking resistance is positively correlated with N2 minor axis (r=0.52) and N2 stem diameter is negatively correlated with N2 length (r=-0.20).【Conclusion】The genetic mechanism of lodging resistance in the F2 population of Yuehesimiao × Xiangyaxiangzhan shows that N2 wall thickness is significantly positively correlated with N2 breaking resistance and is the core trait of stem lodging resistance, which is a quantitative trait controlled by polygenes. Taking N2 wall thickness as the research focus will greatly reduce the complexity of previous research methods for lodging resistance, which clarifies the research goals and directions for future lodging resistance-related researches.

Rice is one of the most important crops in the world, and safe production of rice is related to food safety issues. Rice blast, caused by Magnaporthe oryzae, is a worldwide fungal disease that causes serious losses to rice production. Compared with chemical pesticides control, the breeding and application of disease-resistant cultivars is the most economical and effective way to control the disease. However, the complex and diverse population of blast fungus in the field, excessive use of chemical pesticides, change of temperature environment and other factors cause rapid evolution of M. oryzae isolates, and the resistance of cultivars can only last for 3-5 years. Magnaporthe oryzae generates new races through the mutation of avirulent genes, which can escape or suppress the immune system of rice, causing infection and disease. At present, 26 avirulent genes in blast fungus have been identified, and 14 of them have been cloned, which plays an important role in the infection and colonization of pathogens and in interfering with the immune response of host plants. Further studies on the interaction mechanism of M. oryzae effector protein and rice resistance protein have also been conducted. Understanding the pathogenic mechanism of blast fungus and molecular mechanism of its interaction with rice will help to better understand the pathway of pathogens and the immune response of plant disease resistance genes, to formulate more efficient and green control measures. This review summarized the process of M. oryzae effector protein translocation and secretion in rice cells, the research advances in the interaction between effector proteins and disease-resistance proteins and the regional distribution of effector proteins. And the opportunities and challenges in current researches were discussed and prospected, with an aim to provide references for the molecular mechanism of the interaction between rice and blast fungus, disease-resistance breeding and disease prevention and control strategies.

Upland rice, an ecological type formed by the long-term domestication of rice, is mainly distributed in dry land and hilly land with stable summer rainfall but insufficient irrigation conditions. Currently, the cultivated area of upland rice in the world is about 19 million hm2, accounting for about 12.7% of the total cultivated rice area. With rich resources and a long planting history, upland rice is distributed in different rice growing areas in China. Agriculture is one of the most important sources of greenhouse gas emissions, in which the long-term water layer needs to be established in the process of rice cultivation, accounting for about 16% of the greenhouse gas emissions from agriculture. Many studies have shown that planting upland rice plays an important role in reducing greenhouse gas emissions from paddy fields, which is of great significance for ensuring national food security and achieving national carbon peak and carbon neutrality goals. Due to the relative balance of light, temperature and rainfall in Guangdong Province, double-croping rice is the main planting pattern in each ecological region, and the development of upland rice is relatively lagging. With the decrease of the rural labor force, the shortage of water resources and the continuous occurrence of extreme weather such as high temperature and drought in Guangdong and South China, the market demand for upland rice varieties has increased year by year. This review introduces the drought resistance mechanism, breeding and supporting technologies of upland rice in China and abroad, analyzes the research and planting status of upland rice in Guangdong, and puts forward suggestions on upland rice researches, providing references for molecular breeding and low-carbon cultivation technology of upland rice varieties in Guangdong Province.

Aroma is a crucial determinant of rice taste quality, with volatile organic compounds (VOCs) playing a key role in defining this characteristic. However, limited research has explored the dynamic changes in these aromatic substances during the ripening stages of rice grains. In this study, we analyzed VOCs in rice grains across four ripening stages post-flowering using headspace solid-phase microextraction combined with gas chromatography–mass spectrometry (HS-SPME-GC-MS). A total of 417 VOCs were identified, among which 65 were determined to be key aroma-active compounds based on relative odor activity value (rOAV) analysis. Most of these aroma-active compounds exhibited an accumulation pattern as the grains matured. Notably, 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone and 2-Methyloxolan-3-one had the largest rOAV values. Additionally, (Z)-6-nonenal, (Z,Z)-3,6-nonadienal, 2-thiophenemethanethiol, 5-methyl-2-furanmethanethiol, 2,2,6-trimethyl-cyclohexanone, and 3-octen-2-one were identified as potential key markers for distinguishing rice-grain maturity stages. Moreover, 2-acetyl-1-pyrroline (2-AP), heptanal, and 1-nonanol were identified as marker metabolites differentiating aromatic from non-aromatic brown rice. These findings contribute to a deeper understanding of the dynamic variation and retention of aroma compounds during rice-grain ripening, and they offer valuable insights into the improvement of fragrant rice varieties.

Grain shape in rice (Oryza sativa L.) is a complex trait governed by multiple quantitative trait loci (QTLs). To dissect the genetic basis of rice shape, QTL analysis was conducted for milled rice grain width (MGW), milled rice grain length (MGL), and milled rice length-to-width ratio (MLWR) using a recombinant inbred line (RIL) population of F10 and F11 generations derived from a cross between Yuexiangzhan and Shengbasimiao. A high-density genetic map consisting of 2412 bins was constructed by sequencing 184 RILs, spanning a total length of 2376.46 cM. A total of 19 QTLs related to MGL, MGW, and MLWR were detected under two environments. The range of phenotypic variation attributed to individual QTL ranged from 1.67% to 32.08%. Among those, a novel locus for MGL, MGW and MLWR, designated as qMLWR3.2, was pinpointed within a specific ~0.96-Mb region. Two novel loci for MGW and MLWR, qMLWR11.1 and qMLWR11.2, were verified within ~1.22-Mb and ~0.52-Mb regions using three RIL-developed populations, respectively. These findings lay the foundation for further map-based cloning and molecular design breeding in rice.

Ultrasonic vibration-assisted machining is a promising technique for improving the removability of materials, especially for difficult-to-machine materials, but the material removal mechanism under ultrasonic vibration status is still far from clear. Scratch testing is generally employed to study the material removal mechanism, but currently, there is a lack of instruments capable of performing scratch testing under ultrasonic vibration. To address this gap, this study developed an ultrasonic vibration scratch tester that can perform quantitative ultrasonic vibration-assisted scratch (UVAS) testing of materials. A prototype was designed and fabricated, followed by characterizing its performance parameters. Comparative experiments of conventional scratch (CS) testing and UVAS testing were performed on AL1050 to investigate the effects of ultrasonic vibration on scratch characteristics, such as the scratch depth and coefficient of friction. It was found that compared to CS testing, UVAS testing, with an amplitude of 1.45 µm and a frequency of 20 kHz, achieved a maximum reduction in the coefficient of friction of approximately 22.5% and a maximum increase in the depth of the residual scratch of approximately 175%. These findings confirm the superiority of ultrasonic vibration-assisted machining and demonstrate the requirement for the development of ultrasonic vibration scratch testers.

Rice is one of the most important food crops in the world. Rice disease is a major threat to its yield loss. Bacterial blight caused by the gram-negative bacterium Xanthomonas oryzae pv. oryzae (Xoo), is one of the three major diseases that seriously affect rice yield. The traditional chemical control methods have many drawbacks. The cultivation and planting of rice varieties resistant to bacterial blight is recognized worldwide as the most safe and effective means to control the disease. Identification of resistant germplasm resources and discovery of resistant genes are the premise of resistant varieties breeding. Under the pressure of both natural and artificial selections, new pathogenic varieties have emerged one after another due to the constant variation of bacterial blight pathogens, and the main varieties have gradually lost their disease resistance. Therefore, it is necessary to explore and identify more durable disease resistance genes. In the study, 16 bacterial blight resistance genes that have been cloned are briefly classified, and then three genes Xa23, Xa7 and xa5 that are broad-spectrum resistant to bacterial blight with good application are described in detail from the aspects of gene discovery, location, cloning, mechanism of action, and etc. The conventional breeding, molecular marker-assisted selection breeding, transgenic breeding and gene marker breeding for bacterial blight resistance are introduced. In addition, the prospect of molecular breeding for broad-spectrum resistance to bacterial blight is put forward based on the characteristics of different bacterial blight genes and the problems in current breeding and utilization.

Phenomics refers to the systematic study at the genomic level of all the phenotypes of an organism or cell under a variety of different environmental conditions. With the continuous improvement of plant phenotype acquisition technology and equipment as well as the rapid development of genomics, proteomics, metabolomics, bioinformatics and big data computing technology, high-throughput phenomics analysis plays an increasingly important role in germplasm identification, genetic mapping, functional gene mining and other aspects. High-throughput phenomics research is becoming a key field to break through the future research and application of crop science, providing accurate and efficient decision support for crop breeding and cultivation management. Therefore, it is of great significance to fully exploit multi-omics information and accelerate high-throughput phenotypic studies to fully understand the relationship between crop genotypes, phenotypes and environment, to discover and reveal the regulatory genes and mechanisms of important agronomic traits and to promote the researches of crop functional genomes and crop genetic improvement. In this review, the phenotypic development of phenomics were summarized, the current phenomics research platform and imaging system and its application in crop root structure, canopy structure, biological and abiotic stress were systematically discussed, with a view to providing a reference for highthroughput acquisition and analysis of crop phenotypes and accelerating the application of phenomics in crop breeding.

Yuenongsimiao is not only a conventional rice variety with high-resistance and excellent comprehensive traits, but also a good parent for high-quality rice breeding. The analysis of the characteristics of the derived varieties could provide a theoretical basis for high-quality rice breeding. With Yuenongsimiao (R1212) as the parent, there were 53 rice varieties approved or authorized, of which 43 passed national or provincial approval. These varieties were rich in type, including conventional rice, hybrid rice, aromatic rice and etc. To clarify the characteristics of varieties derived from Yuenongsimiao, the approved derived varieties were selected, and their yield, rice quality, disease and stress resistance performance in the year they participated in the national and provincial regional trials were compared and analyzed. It was found that the yields of these varieties in the regional trials were increased by 0.46%-10.98% compared with these of the control varieties. In term of quality indexes, except for the ungraded seedlings of Q Liangyouyuenongsimiao, both conventional rice and hybrid rice could reach high-quality standards. In terms of disease resistance, some derived varieties resisted blast and bacterial blight, while many derived varieties showed weak resistance to these two diseases. In the identification of lodging and heat resistance, the derived varieties showed strong lodging resistance. Furthermore, except Huiliangyouyuenongsimiao, other varieties showed strong heat resistance phenotypes. These derivatives generally possessed the characteristics of high-yielding stability, good rice quality, strong lodging and heat resistance, which fully reflected the"core"role of Yuenongsimiao as a high-quality rice parent. The main Yuenongsimiao derived varieties, such as Yuehesimiao, Yuejinnongzhan, Longjingyou1212, Jingliangyou1212, Longliangyou1212, Quanyouyuenongsimiao and Huiliangyouyuenongsimiao have been the main local varieties, with good promotion and application prospect in the approved area.

【Objective】Rice seedling transplanting and direct seeding are the most widely used planting methods in Guangdong currently. Exploring the effects of seedling transplanting and direct seeding on rice yield and screening the rice varieties suitable for flooding direct seeding in Guangdong and South China can provide theoretical basis for variety selection and breeding application of direct seeding rice in Guangdong and South China.【Method】Twenty-five rice varieties from Guangdong Province were used as materials to simulate submergence tolerance tests, the growth period, plant height, lodging resistance and yield were measured under two different cultivation modes of seedling transplanting and direct seeding in early and late seasons, and the rice varieties suitable for direct seeding were screened.【Result】The seedling rate of 12 rice varieties, such as Yuexinyinzhan 2, Yuenongsimiao and Yuetaiyouzhan with submergence tolerance reached more than 80%.It was found that the growth period of direct seeding rice was 7-15 d shorter than that of seedling transplanting by analyzing the two cultivation modes of seedling transplanting and direct seeding in early and late seasons. As it showed in the field lodgingresistance phenotype identification, 11 rice varieties had stronger lodging resistance. Yield analysis showed that the yields of direct seeding in early and late seasons were higher than those of seedling transplanting, with an average increase of 0.99 % and 1.25 %, respectively.【Conclusion】Based on the submergence tolerance, lodging resistance and high yield of the tested varieties, 4 varieties including Yuenongsimiao, Yumeizhan, Wushansimiao and Yuteyouzhan were selected to be suitable for direct seeding cultivation pattern in South China.

Rice is one of the food crops with the largest planting area and the highest total output in China, which plays an important role in ensuring national food security. Since the "Green Revolution", China's rice yield per unit area has been greatly improved. However, the lodging problem of rice has long restricted the high and stable yield and excellent quality of rice. A large area of lodging of rice will lead to serious yield loss and rice quality decline. At present, with the continuous improvement of rice yield per unit area, the problem of rice lodging is becoming increasingly prominent, which has been one of the great hidden dangers threatening the normal rice production. Through decades of continuous research, researchers at home and abroad have made great progress in the cause, mechanism, influencing factors, evaluation methods and lodging resistance genetics and breeding of rice. The study summarizes the research progress of rice lodging resistance since the"Green Revolution", combined with the lodging resistance research work experience for many years, comprehensive analyzes the research the origin of rice lodging resistance, clarifies the properties of rice lodging, summarizes the main related factors of rice lodging resistance, and puts forward the relevant countermeasures to raise the capacity of rice lodging resistance. On the basis of the existing research, the main directions of rice lodging resistance breeding, cultivation and molecular mechanism research in the new era are prospected in order to provide references for rice lodging resistance researchers.

With the fast evolution of wireless and networking communication technology, applications of surface acoustic wave (SAW), or Rayleigh wave, resonators are proliferating with fast shrinking sizes and increasing frequencies. It is inevitable that the smaller resonators will be under a strong electric field with induced large deformation, which has to be described in wave propagation equations with the consideration of nonlinearity. In this study, the formal nonlinear equations of motion are constructed by introducing the nonlinear constitutive relation and strain components in a standard procedure, and the equations are simplified by the extended Galerkin method through the elimination of harmonics. The wave velocity of the nonlinear SAW is obtained from approximated nonlinear equations and boundary conditions through a rigorous solution procedure. It is shown that if the amplitude is small enough, the nonlinear results are consistent with the linear results, demonstrating an alternative procedure for nonlinear analysis of SAW devices working in nonlinear state.

Loss of Nestin sensitizes non-small cell lung carcinoma (NSCLC) to oxidative stress. Here, the authors report a feedback loop between Nestin and Nrf2 wherein Nestin competes with Nrf2 for Keap1 binding, preventing Nrf2 degradation, and show the Nestin–Keap1–Nrf2 axis to regulate redox homeostasis in NSCLC.

Temperature is known as one of the abiotic factors that can affect mold growth. Many mold growth prediction models consider temperature as one of the parameters that can significantly impact mold growth indoors, and hence temperature has been targeted by different indoor mold prevention strategies on different premises. For example, European guidelines for libraries suggest a temperature of 19 °C to preserve books. However, running low temperature air-conditioning (AC) costs substantially more energy, and thus a higher temperature (e.g., 25.5 °C) has been regularly proposed as the recommended indoor temperature for general indoor environments in Hong Kong. It is, therefore, needed to understand whether or not the reduction of indoor temperature would lead to better effectiveness of mold prevention. Using Cladosporium cladosporioides (C. cladosporioides) as the model, its germinating spores were challenged in C. cladosporioides to wet-dry cycles with different combinations of relative humidity (RH, 40%, 60% and 80%) and temperature (19 °C and 28 °C) levels. The survival, lipid peroxidation and catalase (CAT) activity of the treated spores were monitored and compared. C. cladosporioides spores showed similar levels of viability, lipid peroxidation and CAT activity when they were exposed to 19 °C and 28 °C at the same RH, but substantially lower survival and higher oxidative stress were observed under the wet-dry cycles with 40% RH dry periods compared with 60% and 80% RH at both temperatures, suggesting that indoor temperature does not tend to affect the resistance of C. cladosporioides to wet-dry cycles as significantly as the RH level of the dry period. Collectively, this study suggests a more important role for moisture over temperature in indoor mold prevention. The outcome of this study may facilitate the sustainable management of indoor mold problems in buildings.

Surface acoustic wave (SAW) devices are one of the indispensable components in the radio frequency (RF) front-end of mobile phones. With the development of mobile communication technology, the requirements for linear specification of devices are more and more strict. Nonlinear distortions of SAW devices have a serious influence on the application of mobile RF modules. To satisfy the strict requirement of linearity of communication system, it is necessary to understand the generation mechanism of nonlinearity and study the accurate modeling, appropriate measurement methods, and nonlinear response elimination technology. In this paper, we summarize the research progress on the nonlinearity of SAW devices in recent years from four aspects: the generation mechanism, simulation methods, measurement system, and suppression technology. The nonlinear harmonics with the nonlinear Mason equivalent circuit model are simulated. Furthermore, harmonics and intermodulation signals of SAW filters are tested by the authors. Thanks to these research studies, it is of great significance to the development of future RF front-end modules with high linear SAW devices.

This paper focuses on the problem of lung nodule image classification, which plays a key role in lung cancer early diagnosis. In this work, we propose a novel model for lung nodule image feature representation that incorporates both local and global characters. First, lung nodule images are divided into local patches with Superpixel. Then these patches are transformed into fixed-length local feature vectors using unsupervised deep autoencoder (DAE). The visual vocabulary is constructed based on the local features and bag of visual words (BOVW) is used to describe the global feature representation of lung nodule image. Finally, softmax algorithm is employed for lung nodule type classification, which can assemble the whole training process as an end-to-end mode. Comprehensive evaluations are conducted on the widely used public available ELCAP lung image database. Experimental results with regard to different parameter setting, data augmentation, model sparsity, classifier algorithms, and model ensemble validate the effectiveness of our proposed approach.

DNA microarrays are powerful tools for global analysis of gene transcript expression. However, their high cost and the need for replication have limited their use. Here, we report a new stripping technique applicable to microarrays hybridized with cRNA with RNase H that is reproducible, leaving the DNA oligonucleotide probes intact and available for adding two additional uses. A Pearson correlation was used to assess the agreement between the first-round hybridization and the second- and third-round hybridizations. Significant correlations (R2, 0.9893 and 0.975; P < 0.001) were observed among virgin arrays and stripped arrays hybridized with the same sample. Additionally, statistical class comparison analysis globally indicated that there were essentially no differences detected following three hybridizations. Dye-swapped microarrays produced similar results. However, arrays stripped with RNase H exhibited decreased efficiency of hybridization signal with increasing use. In the present study, the oligonucleotide microarrays can be used three times.