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31.
Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
32.
Hassan NA Hegab MI Rashad AE Fahmy AA Abdel-Megeid FM 《Nucleosides, nucleotides & nucleic acids》2007,26(4):379-390
The reaction of compounds 1, 2, 3, 4, or 13 with 2-chloroethyl methyl ether or 2,3,4,6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide, afforded some acyclic and cyclic nucleosides of thieno[2,3-d]pyrimidine derivatives. Furthermore, cyclic C-nucleosides 24 and 25 were prepared from the reaction of 20, 21 or from 26, 27 with D-glucose. The antimicrobial evaluation of some prepared products showed promising antimicrobial activity. 相似文献
33.
Niessen M Krause K Horst I Staebler N Klaus S Gaertner S Kebeish R Araujo WL Fernie AR Peterhansel C 《Journal of experimental botany》2012,63(7):2705-2716
The major photorespiratory pathway in higher plants is distributed over chloroplasts, mitochondria, and peroxisomes. In this pathway, glycolate oxidation takes place in peroxisomes. It was previously suggested that a mitochondrial glycolate dehydrogenase (GlcDH) that was conserved from green algae lacking leaf-type peroxisomes contributes to photorespiration in Arabidopsis thaliana. Here, the identification of two Arabidopsis mitochondrial alanine:glyoxylate aminotransferases (ALAATs) that link glycolate oxidation to glycine formation are described. By this reaction, the mitochondrial side pathway produces glycine from glyoxylate that can be used in the glycine decarboxylase (GCD) reaction of the major pathway. RNA interference (RNAi) suppression of mitochondrial ALAAT did not result in major changes in metabolite pools under standard conditions or enhanced photorespiratroy flux, respectively. However, RNAi lines showed reduced photorespiratory CO(2) release and a lower CO(2) compensation point. Mitochondria isolated from RNAi lines are incapable of converting glycolate to CO(2), whereas simultaneous overexpression of GlcDH and ALAATs in transiently transformed tobacco leaves enhances glycolate conversion. Furthermore, analyses of rice mitochondria suggest that the side pathway for glycolate oxidation and glycine formation is conserved in monocotyledoneous plants. It is concluded that the photorespiratory pathway from green algae has been functionally conserved in higher plants. 相似文献
34.
Zaki ME Soliman HA Hiekal OA Rashad AE 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(1-2):1-5
Pyrazolopyranopyrimidines 6a-c and 8a-c were prepared from the reaction of compounds 4a-c or 7a-c with methylamine or ammonium hydroxide solutions. Treatment of compounds 6a-c or 8a-c with 2-chloroethyl methyl ether afforded their corresponding acyclonucleosides 9a-c or 10a-c, respectively, as a new class of acyclonucleosides. All prepared compounds were tested as anti-inflammatory agents and some of them revealed moderate to potent anti-inflammatory activity. 相似文献
35.
36.
Some cyclic and acyclic nucleosides of thieno[2,3-d]-pyrimidine derivatives were synthesized via the reaction of compounds 1 and 2 or 3 and 4 with 2-chloroethyl methyl ether or 2,3,4, 6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide. Nucleosides 9, 10, 15, and 16 were tested as antiviral agents against herpes simplex virus type-1 (HSV-1) and hepatitis-A virus (HAV). Compound 15 showed the highest effect on HSV-1 than the other three compounds, while the four tested compounds did not show any activity against HAV. 相似文献
37.
Muhammad Asad Rashad Rasool Khan Ahmed B. Aljuboory Muhammad Haroon U. Rashid Uttam Kumar Inzamam Ul Haq Aqsa Hafeez Ahmed Noureldeen Khadiga Alharbi 《Phyton》2023,92(4):1161-1172
The beet armyworm (BAW), Spodoptera exigua (Lepidoptera: Noctuidae) is a highly destructive pest of vegetables and
field crops. Management of beet armyworm primarily relies on synthetic pesticides, which is threatening the beneficial
community and environment. Most importantly, the BAW developed resistance to synthetic pesticides with making it
difficult to manage. Therefore, alternative and environment-friendly pest management tactics are urgently required.
The use of pesticidal plant extracts provides an effective way for a sustainable pest management program. To evaluate
the use of pesticidal plant extracts against BAW, we selected six plant species (Lantana camara, Aloe vera, Azadirachta
indica, Cymbopogon citratus, Nicotianatabacum, and Ocimum basilicum) for initial screening experiment. Four out of
six plant species such as A. indica, N. tabacum, C. citratus and O. basilicum showed promising mortality of more than
50%. Therefore, we selected these four plant extracts for the subsequent experiments. Through contact bioassay, A.
indica showed high mortality 66.63%, followed by the N. tabacum 53.33%, at 10% w/v concentration. Similarly, N.
tabacum showed the highest mortality rate, 66% at 10% w/v concentration, followed by the A. indica 46% through
feeding bioassay. Furthermore, the feeding deterrence assay showed that C. citratus had a high antifeedant index
(−50) followed by A. indica (−39), and N. tabacum (−28). In living plant assay, the N. tabacum extract showed a
low mean damage score 3.6 on living cotton plant followed by C. citratus 4.5 and A. indica 5.5. Hence, extracts of
three plant species provided promising results against the BAW, which can minimize the use of synthetic chemicals,
particularly for small landholding farmers. Further studies are also required to evaluate the effects of these plant extract
against BAW on cotton plants under field conditions to optimize the further use. 相似文献
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40.
Mohamed Salih Mahfouz Bahaa-eldin E. A. Rahim Yahya M. H. Solan Anwar M. Makeen Rashad Mohammed Alsanosy 《PloS one》2015,10(8)
The use of khat (Catha edulis) is a major public health and social problem that is believed to be growing globally. The khat chewing habit is prevalent in all areas of the Jazan region, Kingdom of Saudi Arabia (KSA). However, few studies have been conducted at the community level to investigate the khat chewing habits in this area. This study was conducted with the aim of assessing the prevalence and predictors of khat chewing among the Jazan community population. A cross-sectional study was conducted with a sample (n = 4,500) of the Jizani population who attended primary heath care centers in Jazan region. The participants were selected using a two-stage cluster random sampling. A structured questionnaire was used for data collection. The overall lifetime prevalence of khat chewing was 33.2% (95% CI 31.8–34.7) and was significantly higher for males 42.2% (95% CI 40.4–43.9) than for females 11.3% (95% CI 9.6–13.1) (P < 0.001). Current khat chewers accounted for 28.7% (95% CI 27.4–30.1) of the population sampled; 36.9% (95% CI 35.2–38.6) of whom were males, which is a significantly higher percentage than the 8.7% (95% CI 7.3–10.4) of current khat chewers who were females (P < 0.001). The multivariate logistic regression analysis suggests that the most important independent predictors of khat chewing were having a friend who chewed khat (OR = 20.1, P < 0.001), participant''s smoking status (OR) = 3.9, P < 0.001), friend''s smoking status (OR = 2.2, P < 0.001), gender (OR = 2.2, P < 0.001) and educational level (OR = 1.5, P < 0.05). A large proportion of the Jizani populations chew khat. Government and non-governmental organizations NGOs should design and strengthen community prevention programs to curb the high prevalence of khat use. 相似文献