Isolation and characterization of the EgWRI1 promoter from oil palm (Elaeis guineensis Jacq.) and its response to environmental stress and ethylene.

WRI1 is a plant-specific transcription factor that enhances the accumulation of oils through the upregulation of the expression of genes involved in glycolysis and fatty acid biosynthesis. In this study, the EgWRI1 promoter from oil palm was isolated and characterized in transgenic Arabidopsis. The sequence analysis results revealed that various putative plant regulatory elements are present in the EgWRI1 promoter region. The EgWRI1 promoter and beta-glucuronidase (GUS) reporter gene were transcriptionally fused and transformed into Arabidopsis thaliana. Histochemical analysis revealed that GUS staining was very strong in whole seedlings, especially the stems, leaves, and siliques. Moreover, GUS staining was strong in the silique coats but weak in the seeds. Furthermore, to detect whether EgWRI1 was induced by environmental stress, we detected the expression efficiency of the EgWRI1 promoter in transgenic Arabidopsis treated with low temperature, darkness, and exogenous ethylene. The results showed that the activity of the EgWRI1 promoter was induced by darkness but suppressed significantly when exposed to exogenous ethylene. When treated with low temperature, the activity of the EgWRI1 promoter was first reduced after 24 hours but recovered after 48 hours. Taken together, these results reveal the features of the EgWRI1 promoter from oil palm, which will be helpful for improving oil accumulation in oil palm via reasonable cultivation methods

Production Capacity Variations of Horizontal Wells in Tight Reservoirs Controlled by the Structural Characteristics of Composite Sand Bodies: Fuyu Formation in the Qian’an Area of the Songliao Basin as an Example

In order to improve the combined exploitation efficiency of horizontal and vertical wells, and given the fact that the complex and varied spatial structure of sand bodies in the Fuyu oil layer in the Qian’an area of Songliao Basin leads to significant differences in production characteristics of horizontal wells, the sand body types and internal spatial structure are finely dissected according to the theory of configuration analysis, and the internal spatial structure is divided into three configuration styles: spatial clipping type, overlapping type, and separation type. Then, by comparing the productivity characteristics of horizontal wells with different configurations of sand bodies, combined with the analysis of fluid flow law under horizontal well volume fracturing, a main fracture–fracture network–matrix coupled fluid flow model in a tight reservoir based on composite sand body configuration is established. Combined with the actual volume fracturing the horizontal well area, the productivity curves of each cluster in the horizontal section after numerical simulation of volume fracturing of typical horizontal well groups are extracted, which are divided into four types: high-yield stable type, high-yield two-stage type, high-yield rapid-decline type, and low-yield rapid-decline type, and the coupling relationship between the productivity characteristics of each cluster in the horizontal well volume fracturing and sand body configuration style is established, which provides a theoretical basis for the adjustment of different sand body development methods in subsequent oilfields

Identification and Analysis of Genes Involved in Double Fertilization in Rice

Double fertilization is a key determinant of grain yield, and the failure of fertilization during hybridization is one important reason for reproductive isolation. Therefore, fertilization has a very important role in the production of high-yield and well-quality hybrid of rice. Here, we used RNA sequencing technology to study the change of the transcriptome during double fertilization with the help of the mutant fertilization barrier (feb) that failed to finish fertilization process and led to seed abortion. The results showed that 1669 genes were related to the guided growth of pollen tubes, 332 genes were involved in the recognition and fusion of the male–female gametes, and 430 genes were associated with zygote formation and early free endosperm nuclear division. Among them, the genes related to carbohydrate metabolism; signal transduction pathways were enriched in the guided growth of pollen tubes, the genes involved in the photosynthesis; fatty acid synthesis pathways were activated by the recognition and fusion of the male–female gametes; and the cell cycle-related genes might play an essential role in zygote formation and early endosperm nuclear division. Furthermore, among the 1669 pollen tube-related genes, it was found that 7 arabinogalactan proteins (AGPs), 1 cysteine-rich peptide (CRP), and 15 receptor-like kinases (RLKs) were specifically expressed in anther, while 2 AGPs, 7 CRPs, and 5 RLKs in pistil, showing obvious unequal distribution which implied they might play different roles in anther and pistil during fertilization. These studies laid a solid foundation for revealing double fertilization mechanism of rice and for the follow-up investigation

Dynamic Evaluation of Flow Unit Based on Reservoir Evolution: A Case Study of Neogene Guantao Ng3 Formation in M Area, Gudao, Bohai Bay Basin

To clarify the dynamic evolution characteristics of reservoir flow units during water injection development, the upper member of the Neogene Guantao formation in Block M of Gudao Oilfield is taken as a case study. Based on logging data, water injection profile test data, subwell data, and production performance data, among others, the flow zone index (FZI static) was proposed as the static evaluation parameter of the flow unit. The relationship between cumulative water injection (WT) and FZI change (△FZI) was fitted. Hence, the △FZI caused by water injection is combined with the static parameter of flow unit evaluation (FZI static) as the dynamic parameter of flow unit evaluation (FZI dynamic). The comprehensively evaluated reality of flow units in different periods is characterized by formula FZI static+△FZI=FZI dynamic. The study shows that as the division standard of the flow unit, the FZI has a good correlation with the test results of the water absorption profile, such as water absorption intensity and relative water injection volume. Using the FZI as the static parameter of flow unit evaluation, four types of flow units were divided as follows: type I flow unit, FZI≥4.1; type II flow unit, 4.1>FZI≥2.4; type III flow unit, 2.4>FZI≥1.7; type IV flow unit, 1.7>FZI. The reservoir porosity and permeability characteristics of different flow units are highly correlated. Moreover, the relative permeability curve confirms that different flow units have different seepage capacities. Though, comparing characteristic reservoir parameters in different periods, the reservoir’s physical parameters became more conducive to fluid flow with the water injection development. The increase in the same water injection rate for type I and II flow units was greater than that for type III and IV flow units. Furthermore, when type I flow units were continuously distributed in a large area, high water consumption bands were formed, absorbing most of the water injection in the water injection wells. Hence, the waterflood efficiency was low. The change in different flow units was mainly controlled by the injection production well pattern and WT. Combined with the relative change characteristics of interlayer flow units, the changes can be divided into increasing type change and decreasing type changes. Finally, according to the distribution characteristics of different flow units, oil saturation, and water flooding results, strategies for tapping the potential of the remaining oil from three aspects (plane, interlayer, and inner layer) were formulated

Characterization and Functional Analysis of a Type 2 Diacylglycerol Acyltransferase (DGAT2) Gene from Oil Palm (Elaeis guineensis Jacq.) Mesocarp in Saccharomyces cerevisiae and Transgenic Arabidopsis thaliana

Oil palm (Elaeis guineensis Jacq.) is the highest oil-yielding plant in the world, storing 90 and 60% (dry weight) oil in its mesocarp and kernel, respectively. To gain insights into the oil accumulation mechanism, one of the key enzymes involved in triacylglycerol (TAG) biosynthesis, a Type 2 diacylglycerol acyltransferase (DGAT2) from oil palm, was characterized for its in vivo activity. EgDGAT2 is highly expressed in mesocarp during the last two developmental stages while large amounts of oil are accumulated at the highest rate during ripening. Heterologous expression of EgDGAT2 in mutant yeast H1246 restored TAG biosynthesis with substrate preference toward unsaturated fatty acids (FAs) (16:1 and 18:1). Furthermore, seed-specific overexpression of EgDGAT2 in Arabidopsis thaliana enhanced the content of polyunsaturated FAs 18:2 and 18:3 (each by 6 mol%) in seed TAGs, when compared to that from wild-type Arabidopsis. In turn, the proportion of 18:0 and 20:0 FAs in seed TAGs from EgDGAT2 transgenic lines decreased accordingly. These results provide new insights into understanding the in vivo activity of EgDGAT2 from oil palm mesocarp, which will be of importance for metabolic enhancement of unsaturated FAs production

Bibliometric analysis of medical and health research collaboration between China and ASEAN countries

Objective To reveal the characteristics, development trend and potential opportunities of China–ASEAN collaboration in the medical and health field based on bibliometrics. Methods Scopus and International Center for the Study of Research Lab (ICSR Lab) was used to analyze the scale, collaboration network and distribution, impact of cooperative papers, collaboration dominance and evolution of the literature on China–ASEAN medical and health collaboration in the Scopus database from 1992 to 2022. Results From 1992 to 2022, 19,764 articles on medical and health collaboration between China and ASEAN were filtered for analysis. The number of China–ASEAN collaborations has shown a clear upward trend over the years, indicating a gradually closer and improved collaboration relationship overall. The institutional collaboration network between China and ASEAN countries was obviously clustered, and the network connectivity was limited. The substantial differences between the median and mean values of citation impact of China–ASEAN medical and health research collaboration reflected that the collaboration was ‘less’ but ‘better’. The dominance share of collaboration between China and the main ASEAN countries was fluctuating upward and has become more and more stable after 2004. Most of the China–ASEAN collaboration focused on their own characteristic research topics. In recent years, collaboration in infectious diseases and public health had expanded significantly, while other research topics had maintained in a complementary development trend. Conclusion Collaboration between China and ASEAN in the medical and health field has exhibited a progressively closer relationship, and the trend of complementary research has remained stable. However, there are still areas of concern, including the limited scale of collaboration, narrow scope of participation and weak dominance

Applications of synchrotron-based X-ray diffraction in investigating thermal barrier coatings

Thermal barrier coatings play crucial roles in protecting the hot end components of aero-engines against high-temperature erosion. They must suffer extremely harsh environments including high temperatures, heavy loads, and large internal temperature gradients, which would result in various complex failures. Therefore, it is important to unveil these failure mechanisms to minimize and even prevent them for obvious reasons. Strain/stress evolution between different layers and foreign material erosion are the main failure mechanisms of thermal barrier coatings, which are well suited to be investigated using synchrotron X-ray diffraction. With its tunable energy, high flux, and many other advantages, synchrotron-based X-ray diffraction has become an advanced non-destructive characterization technique for engineering materials yielding important information including their compositions and residual stress which also provides spatial and temporal resolution that is vital for understanding their service performance. This paper presents a concise review of the applications of synchrotron-based X-ray diffraction in investigating thermal barrier coatings to explore their failure mechanisms

Identification and characterization of a plastidial ω-3 fatty acid desaturase <i>EgFAD8</i> from oil palm (<i>Elaeis guineensis</i> Jacq.) and its promoter response to light and low temperature

<div><p>In higher plants, ω-3 fatty acid desaturases are the key enzymes in the biosynthesis of alpha-linolenic acid (18:3), which plays key roles in plant metabolism as a structural component of both storage and membrane lipids. Here, the first ω-3 fatty acid desaturase gene was identified and characterized from oil palm. The bioinformatic analysis indicated it encodes a temperature-sensitive chloroplast ω-3 fatty acid desaturase, designated as <i>EgFAD8</i>. The expression analysis revealed that <i>EgFAD8</i> is highly expressed in the oil palm leaves, when compared with the expression in the mesocarp. The heterologous expression of <i>EgFAD8</i> in yeast resulted in the production of a novel fatty acid 18:3 (about 0.27%), when fed with 18:2 in the induction culture. Furthermore, to detect whether <i>EgFAD8</i> could be induced by the environment stress, we detected the expression efficiency of the <i>EgFAD8</i> promoter in transgenic Arabidopsis treated with low temperature and darkness, respectively. The results indicated that the promoter of <i>EgFAD8</i> gene could be significantly induced by low temperature and slightly induced by darkness. These results reveal the function of EgFAD8 and the feature of its promoter from oil palm fruits, which will be useful for understanding the fuction and regulation of plastidial ω-3 fatty acid desaturases in higher plants.</p></div

Total fatty acid composition of transformed yeast with <i>EgFAD8</i> or pYES2.

<p>All experiments were carried out in triplicate. Asterisks indicate statistically significant differences compared with the control (Student’s <i>t</i> test: **, p < 0.01). 16:0, palmitic acid; 16:1, palmitoleic acid; 18:0, stearic acid; 18:1, oleic acid; 18:2, linoleic acid; 18:3,alpha linoleic acid.</p