Influence of multi-stage volcanic events on the Late Cretaceous-Paleogene reservoirs and its geological significance in the northern Central Myanmar Basin

The northward subduction of the Neo-Tethys oceanic crust triggered multiple magmatic activities in the West Myanmar Arc,which in turn influenced the deposition of sedimentary pyroclastic rocks from the Cretaceous to Eocene strata in the Central Myanmar Basin(CMB).The pore structure of these lithologic reservoirs is complex and rich in tuffaceous sandstone,which plays an adverse role in reservoir development in this region.To understand the development characteristics and genetic mechanism of the pyroclastic rocks within three sets of reservoirs in this area,a comprehensive analysis was conducted through borehole core observations,thin section identification,scanning electron microscope analysis,and mercury injection tests.The tuffaceous sandstone from the upper Cretaceous to the Eocene is dominated by intermediate-acid volcanic rock debris.The pyroclastic rocks exhibit evident chloritization and ironization,with residual intergranular pores being the principal type accompanied by a smaller amount of intergranular dissolved pores and intragranular dissolved pores.The highest porosity is observed in the Eocene tuffaceous sandstone,ranging from 8%to 12%.The Late Cretaceous to Paleocene sandstones exhibit lower porosity levels of only 4%-6%.These reservoirs are characterized by their low porosity and low-permeability.Despite the presence of a good source rock in this area,the volcanic debris particles filling the pores,as well as their subsequent devitrification,chloritization,and limonite mineralization,result in pore throat blockage and narrowing.The reservoirs in this area are small in size,exhibit poor reservoir connectivity and lateral continuity,and fail to meet the necessary conditions for commercial-scale hydrocarbon accumulation and migration.

A Study on the Application of Task-Driven Teaching Method in High School Mathematics Teaching: Taking “The Determination of Vertical Line and Plane” as an Example

The“Ordinary High School Mathematics Curriculum Standards(2017 Edition,2020 Revision)”clearly stated in“Teaching Suggestions”that“teaching activities based on the core literacy of mathematics should grasp the essence of mathematics,create appropriate teaching situations,put forward appropriate mathematical questions,stimulate students to think and communicate,and form and develop the core literacy of mathematics.”The task-driven teaching model is a new type of teaching method that takes tasks as the main line,teachers as the guide,and students as the main body,which can enable students to engage deeply in classroom discussions and think actively.Based on the characteristics and principles of the task-driven teaching method,this paper designs a high school mathematics classroom teaching based on the task-driven teaching method,hoping to provide a reference for the majority of front-line teachers.

Mobility control of unmanned aerial vehicle as communication relay in airborne multi-user systems

In this paper, a model-based adaptive mobility control method for an Unmanned Aerial Vehicle(UAV) acting as a communication relay is presented, which is intended to improve the network performance in airborne multi-user systems. The mobility control problem is addressed by jointly considering unknown Radio Frequency(RF) channel parameters, unknown multi-user mobility, and non-available Angle of Arrival(AoA) information of the received signal. A Kalman filter and a least-square-based estimation algorithm are used to predict the future user positions and estimate the RF channel parameters between the users and the UAV, respectively. Two different relay application cases are considered: end-to-end and multi-user communications. A line search algorithm is proposed for the former, with its stability given and proven, whereas a simplified gradient-based algorithm is proposed for the latter to provide a target relay position at each decision time step, decreasing the two-dimensional search to a one-dimensional search. Simulation results show that the proposed mobility control algorithms can drive the UAV to reach or track the optimal relay position movement, as well as improving network performance. The proposed method reflects the properties of using different metrics as objective network performance functions.

Effect of particle shape and size on flow properties of lactose powders

The shape and size of particles are understood to affect the bulk behaviour of powders, though there are but few studies that present quantitative information on the relationship between particle shape and the flow properties of powder. This is due in part to the lack of techniques for rapidly determining both particle shape and the range of flow characteristics that describe the response of powders to the stress and shear experienced during their processing. This study presents data that quantifies the influence of particle shapeJsize of three different lactose powders on their respective flow and bulk characteristics. Two of the samples differ in size but have similar shapes; the third sample is more spherical but similar in size to one of the other two samples, The results demonstrate that in addition to particle size, particle shape significantly affect the flow characteristics of a powder over a wide range of stress conditions.

Making Use of Plant uORFs to Control Transgene Translation in Response to Pathogen Attack

Reducing crop loss to diseases is urgently needed to meet increasing food production challenges caused by the expanding world population and the negative impact of climate change on crop productivity.Disease-resistant crops can be created by expressing endogenous or exogenous genes of interest through transgenic technology.Nevertheless,enhanced resistance by overexpressing resistance-produced genes often results in adverse developmental affects.Upstream open reading frames(uORFs)are translational control elements located in the 5′untranslated region(UTR)of eukaryotic mRNAs and may repress the translation of downstream genes.To investigate the function of three uORFs from the 5′-UTR of ACCELERATED CELL 11(uORFsACD11),we develop a fluorescent reporter system and find uORFsACD11 function in repressing downstream gene translation.Individual or simultaneous mutations of the three uORFsACD11 lead to repression of downstream translation efficiency at different levels.Importantly,uORFsACD11-mediated translational inhibition is impaired upon recognition of pathogen attack of plant leaves.When coupled with the PATHOGENESIS-RELATED GENE 1(PR1)promoter,the uORFsACD11 cassettes can upregulate accumulation of Arabidopsis thaliana LECTIN RECEPTOR KINASE-VI.2(AtLecRKVI.2)during pathogen attack and enhance plant resistance to Phytophthora capsici.These findings indicate that the uORFsACD11 cassettes can be a useful toolkit that enables a high level of protein expression during pathogen attack,while for ensuring lower levels of protein expression at normal conditions.

An exotic origin of the eastern East China Sea basement before~150 Ma

It is widely accepted that the South China Block was formed by multi-terrane accretion events[1],and the East China Sea(ECS)basement is believed to be the offshore extent of Cathaysia[2,3].Recently,it has been suggested that the ECS basement is an exotic terrane(Fig.1a)that collided with Eurasia at~88[4]or 100 Ma[5];these speculations are based on the onshore granitoid magmatism gap between~90 and~50 Ma[5]or the specific geophysical features and crustal structure of the ECS[4].If supported,this hypothesis would significantly change the understanding of regional geology.However,the crustal evolution of the ECS is still poorly understood and the proposed collision also lacks effective constraints.