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The numerical simulation of reservoir mud invasion is widely used for studying the dynamic invasion process. To investigate the saturation changes of the three phases (water, oil, and mud filtrate) during mud infiltration into intact formations, this study presents a mathematical model for three-phase invasion in cylindrical coordinates. The principle of mud intrusion into the reservoir allows the derivation of the basic equation of three-phase mud seepage from Darcy's law and the law of mass conservation. This is followed by the derivation of the differential equations of pressure and three-phase saturation during mud intrusion. A numerical simulation program for the three-phase seepage flow of mud intrusion is written using the finite-difference method. An adaptive time-step algorithm is developed to address the inadaptability of the intrusion algorithm in the case of mud surges. Additionally, an epithermal effect algorithm is developed to address the problem of mud particles entering the stratum and affecting the absolute permeability. The results show that, as the porosity increases, the radial depth of intrusion decreases, along with a reduction in the invaded annulus range. It can be demonstrated that, when the reservoir pressure is maintained at a constant level, the size of the borehole pressure leads to an increase in the depth of radial intrusion and the extent of the intrusion annulus, under different differential pressure conditions. [ABSTRACT FROM AUTHOR]

Abstract Evolutionary studies of plant groups which are distributed in vast geographical regions and face different ecological and environmental conditions are important as they through light on different mechanisms of local adaptation and species divergence through time. The genus Avicennia is one of these plant groups which inspire of few species show interesting geographical distribution with some degree of species-specific geographical isolations. In general, very limited molecular phylogenetic investigations have been carried out in the genus Avicennia, and therefore we conducted the present study with the following aims: 1. To estimate the species divergence time based on different nuclear and chloroplast DNA regions, separately. This will illustrate how different genetic regions evolved in this genus, 2. To identify the sequences with potential adaptive value against geographical variable by latent factor mixed models (LFMM) analysis, 3. To illustrate the phylogenetic signal of these DNA regions and their role in speciation within the genus and, 4. To introducing a new computational strategy for estimating adaptive time for the sequences. The results showed that different genetic regions may produce different species divergent time, both the nuclear ribosomal internal transcribed spacer (ITS) region and chloroplast DNA sequences, contained potentially adaptive single nucleotide polymorphisms (SNPs).We could present a suggestive time for these adaptive sequences for the first time. In conclusion both local adaptation and independent mutations seem to have played role in Avicennia speciation and evolution.

Evolutionary studies of plant groups which are distributed in vast geographical regions and face different ecological and environmental conditions are important as they through light on different mechanisms of local adaptation and species divergence through time. The genus Avicennia is one of these plant groups which inspire of few species show interesting geographical distribution with some degree of species-specific geographical isolations. In general, very limited molecular phylogenetic investigations have been carried out in the genus Avicennia, and therefore we conducted the present study with the following aims: To estimate the species divergence time based on different nuclear and chloroplast DNA regions, separately. This will illustrate how different genetic regions evolved in this genus, To identify the sequences with potential adaptive value against geographical variable by latent factor mixed models (LFMM) analysis, To illustrate the phylogenetic signal of these DNA regions and their role in speciation within the genus and, To introducing a new computational strategy for estimating adaptive time for the sequences. The results showed that different genetic regions may produce different species divergent time, both the nuclear ribosomal internal transcribed spacer (ITS) region and chloroplast DNA sequences, contained potentially adaptive single nucleotide polymorphisms (SNPs).We could present a suggestive time for these adaptive sequences for the first time. In conclusion both local adaptation and independent mutations seem to have played role in Avicennia speciation and evolution. [ABSTRACT FROM AUTHOR]