Here is one of the possible solutions for this exercise regexprep():
Text=readlines('Citation.txt') % Read data file with texts and numbers
Text = 27×1 string array
"JOURNAL=Frontiers in Plant Science "
"→"
"VOLUME=11 "
"→"
"YEAR=2020 "
"→→"
"URL=https://www.frontiersin.org/articles/10.3389/fpls.2020.613760 "
"→ "
"DOI=10.3389/fpls.2020.613760 "
"→"
"ISSN=1664-462X "
""
"ABSTRACT=Excessive nitrogen (N) application is widespread in Southern China. The effects of N fertilization on soil properties and crop physiology are poorly understood in "
"tropical red loam soil. We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic "
"enzymes, soluble matters) on banana leaves, soil properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical "
"region of southern China. The N rates tested were 0 (N<sub>0</sub>), 145 (N<sub>145</sub>), 248 (N<sub>248</sub>), 352 (N<sub>352</sub>), 414 (N<sub>FT</sub>), and 455 (N<sub>455</sub>) "
"g N per plant. The correlations among soil factors, leaf physiological factors and crop yield were evaluated. The results indiated that the high rates of N fertilization (N<sub>FT</sub> "
"and N<sub>455</sub>) significantly decreased soil available potassium (K) content, available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar "
"contents compared with lower N rates. The N<sub>352</sub> treatment had the highest crop yields compared with higher N rates treatments, followed by the N<sub>455</sub> treatment. However, "
"there were no significant differences in crop yields among N fertilization treatments. Factor analysis showed that the N<sub>352</sub> treatment had the highest integrated score for soil "
"and leaf physiological factors among all treatments. Moreover, the N<sub>352</sub> treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was "
"significantly and positively linearly correlated with the integrated score (r = 0.823, p < 0.05). Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive "
"effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, invertase, acid phosphatase and available P were the most important factors impacting leaf"
" physiological attributes. Cluster analysis demonstrated distinct differences in N application treatment related to variations in soil and leaf factors. This study suggested that excessive "
"N fertilization had a negative effect on soil fertility, crop physiology and yield. The lower N rates were more effective in improving crop yield than higher rates of N fertilization. "
"The N rate of 352 g N per plant (N<sub>352</sub>) was recommended to reduce excess N input while maintaining the higher yield for local farmers’ banana planting."
""
A = regexprep(Text, '\d+(?:_(?=\d))?', '') % All numbers removed
A = 27×1 string array
"JOURNAL=Frontiers in Plant Science "
"→"
"VOLUME= "
"→"
"YEAR= "
"→→"
"URL=https://www.frontiersin.org/articles/./fpls.. "
"→ "
"DOI=./fpls.. "
"→"
"ISSN=-X "
""
"ABSTRACT=Excessive nitrogen (N) application is widespread in Southern China. The effects of N fertilization on soil properties and crop physiology are poorly understood in "
"tropical red loam soil. We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic "
"enzymes, soluble matters) on banana leaves, soil properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical "
"region of southern China. The N rates tested were (N<sub></sub>), (N<sub></sub>), (N<sub></sub>), (N<sub></sub>), (N<sub>FT</sub>), and (N<sub></sub>) "
"g N per plant. The correlations among soil factors, leaf physiological factors and crop yield were evaluated. The results indiated that the high rates of N fertilization (N<sub>FT</sub> "
"and N<sub></sub>) significantly decreased soil available potassium (K) content, available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar "
"contents compared with lower N rates. The N<sub></sub> treatment had the highest crop yields compared with higher N rates treatments, followed by the N<sub></sub> treatment. However, "
"there were no significant differences in crop yields among N fertilization treatments. Factor analysis showed that the N<sub></sub> treatment had the highest integrated score for soil "
"and leaf physiological factors among all treatments. Moreover, the N<sub></sub> treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was "
"significantly and positively linearly correlated with the integrated score (r = ., p < .). Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive "
"effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, invertase, acid phosphatase and available P were the most important factors impacting leaf"
" physiological attributes. Cluster analysis demonstrated distinct differences in N application treatment related to variations in soil and leaf factors. This study suggested that excessive "
"N fertilization had a negative effect on soil fertility, crop physiology and yield. The lower N rates were more effective in improving crop yield than higher rates of N fertilization. "
"The N rate of g N per plant (N<sub></sub>) was recommended to reduce excess N input while maintaining the higher yield for local farmers’ banana planting."
""
(2) another data file:
Atext=readlines('DATA_TEXT.txt')
Atext = 16×1 string array
"ABSTRACT={The effects of N fertilization on soil properties and crop physiology are poorly understood in tropical red loam soil."
" We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic enzymes, soluble matters) on banana leaves, soil "
"properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical region of southern China. The N rates tested were 0 (N<sub>0</sub>), "
"145 (N<sub>145</sub>), 248 (N<sub>248</sub>), 352 (N<sub>352</sub>), 414 (N<sub>FT</sub>), and 455 (N<sub>455</sub>) g N per plant. The correlations among soil factors, leaf physiological factors "
"and crop yield were evaluated. The results indiated that the high rates of N fertilization (N<sub>FT</sub> and N<sub>455</sub>) significantly decreased soil available potassium (K) content, "
"available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar contents compared with lower N rates. The N<sub>352</sub> treatment had the highest crop yields "
"compared with higher N rates treatments, followed by the N<sub>455</sub> treatment. However, there were no significant differences in crop yields among N fertilization treatments. "
"Factor analysis showed that the N<sub>352</sub> treatment had the highest integrated score for soil and leaf physiological factors among all treatments. Moreover, the N<sub>352</sub> "
"treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was significantly and positively linearly correlated with the integrated score (r = 0.823, p < 0.05). "
"{1 2 3 4 5 6 7 8 9 10}. 2023. Feb 18, 12:24 am."
"Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, "
"invertase, acid phosphatase and available P were the most important factors impacting leaf physiological attributes. Cluster analysis demonstrated distinct differences in N application "
"treatment related to variations in soil and leaf factors. This study suggested that excessive N fertilization had a negative effect on soil fertility, crop physiology and yield. "
"The lower N rates were more effective in improving crop yield than higher rates of N fertilization. The N rate of 352 g N per plant (N<sub>352</sub>) was recommended to reduce excess"
" N input while maintaining the higher yield for local farmers’ banana planting.}"
"}"
A = regexprep(Atext, '\d+(?:_(?=\d))?', '')
A = 16×1 string array
"ABSTRACT={The effects of N fertilization on soil properties and crop physiology are poorly understood in tropical red loam soil."
" We conducted a field experiment to evaluate the effect of nitrogen fertilization rates on physiological attributes (chlorophyll, plant metabolic enzymes, soluble matters) on banana leaves, soil "
"properties (soil enzymes, soil organic matter (SOM), soil available nutrients) as well as banana crop yield in a subtropical region of southern China. The N rates tested were (N<sub></sub>), "
" (N<sub></sub>), (N<sub></sub>), (N<sub></sub>), (N<sub>FT</sub>), and (N<sub></sub>) g N per plant. The correlations among soil factors, leaf physiological factors "
"and crop yield were evaluated. The results indiated that the high rates of N fertilization (N<sub>FT</sub> and N<sub></sub>) significantly decreased soil available potassium (K) content, "
"available phosphorus (P) content, glutamine synthetase (GS) activity, and soluble protein and sugar contents compared with lower N rates. The N<sub></sub> treatment had the highest crop yields "
"compared with higher N rates treatments, followed by the N<sub></sub> treatment. However, there were no significant differences in crop yields among N fertilization treatments. "
"Factor analysis showed that the N<sub></sub> treatment had the highest integrated score for soil and leaf physiological factors among all treatments. Moreover, the N<sub></sub> "
"treatment was the most effective in improving carbon and nitrogen metabolism in banana. Crop yield was significantly and positively linearly correlated with the integrated score (r = ., p < .). "
"{ }. . Feb , : am."
"Path analysis revealed that invertase, SOM and sucrose synthase (SS) had a strong positive effect on banana yield. Canonical correspondence analysis (CCA) suggested that available K, "
"invertase, acid phosphatase and available P were the most important factors impacting leaf physiological attributes. Cluster analysis demonstrated distinct differences in N application "
"treatment related to variations in soil and leaf factors. This study suggested that excessive N fertilization had a negative effect on soil fertility, crop physiology and yield. "
"The lower N rates were more effective in improving crop yield than higher rates of N fertilization. The N rate of g N per plant (N<sub></sub>) was recommended to reduce excess"
" N input while maintaining the higher yield for local farmers’ banana planting.}"
"}"