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31.
Rabia Sattar Rubina Mukhtar Muhammad Atif Muhammad Hasnain Ali Irfan 《Journal of heterocyclic chemistry》2020,57(5):2079-2107
The presence of benzoxazole moiety in most of the heterocyclic compounds is well reported. The present literature review mainly highlights the novel synthetic transformation and describes the biological potential of most of the heterocyclic compounds by virtue of presence of benzoxazole framework. Most of the researchers have revealed that benzoxazole derivatives exhibit significant antibacterial, anti-inflammatory, antifungal, anticancer, analgesic, antiviral, anti-tubercular, and anthelmintic activities. Benzoxazole moieties also act as tyrosinase inhibitor and cholesterol ester transfer protein inhibitor. This literature review may provide an opportunity to the chemists to design new derivatives of benzoxazole that proved to be the successful agent in view of safety, effectiveness, and efficacy. 相似文献
32.
The experimental transverse momentum distributions of negative pions produced in d 12C, 4He12C, and 12C12C collisions at 4.2 A GeV/c were analyzed in the framework of Hagedorn Thermodynamic Model. The spectral temperatures of π ? mesons as well as their relative contributions to the total multiplicity of π ? mesons were extracted from fitting the p t spectra by two-temperature Hagedorn function. The results were compared systematically with the earlier results obtained from analysis of non-invariant center-of-mass energy spectra of negative pions produced in the analyzed collisions. 相似文献
33.
The production of Δ
0(1232)-resonances in p + 12C collisions at 4.2 GeV/c was investigated with 4π acceptance. The masses and widths of the resonances were obtained from ananalysis of foreground and background invariant-mass
distributions of pπ
− pairs obtained using an angular criterion. The fraction of charged π
−-mesons coming from the Δ
0(1232) decay was estimated and compared to those obtained in earlier analyses. The momentum, transverse momentum, kinetic
energy, rapidity, and emission angle distributions as well as the invariant cross-sections of Δ
0(1232)-resonances werere constructed in the laboratory frame. The freeze-out temperature of theΔ
0(1232)-resonances produced in p + 12C collisions was estimated and compared to the freeze-out temperatures obtained using different methods for Δ(1232)-resonances produced in other experiments with different sets of colliding nuclei at various incident energies. 相似文献
34.
Khusniddin K. Olimov Mahnaz Q. Haseeb Alisher K. Olimov Imran Khan 《Central European Journal of Physics》2011,9(6):1393-1409
The production of Δ0(1232)-resonances in p+12C collisions at 4.2 GeV/c was analyzed with 4π acceptance. The mass distribution of Δ0(1232) was reconstructed using an angular criterion. The fraction of charged π
−-mesons coming from Δ0(1232) decay was estimated and compared to those obtained in earlier works. The momentum, transverse momentum, kinetic energy,
and rapidity distributions as well as invariant cross sections of Δ0(1232)-resonances were reconstructed in the laboratory frame. The mean kinematical characteristics of the reconstructed Δ0(1232) were compared to those of participant protons in experiment and within some of the models. The freeze-out temperature
of Δ0(1232) estimated in the present analysis was compared with those obtained using different methods for Δ(1232) produced with
other sets of colliding nuclei at various incident energies. The relative number of nucleons excited to Δ0 (1232) at freeze-out conditions in p+12C collisions was estimated. 相似文献
35.
M. K. Suleymanov E. U. Khan K. Ahmed M. Q. Haseeb F. Tahir Y. H. Huseynaliyev M. Ajaz K. H. Khan Z. Wazir 《Indian Journal of Physics》2011,85(7):1047-1050
We discuss that the QCD critical point could appear in central collisions in percolation cluster. We suggest to use the effects
of nuclear transparency and that of the light nuclear production to identify the critical point. 相似文献
36.
Abdul?Haseeb?AhmedEmail authorView authors OrcID profile Ijaz?M.?Qureshi M.?Habib?Mahmood 《Applied magnetic resonance》2017,48(8):841-857
Motion correction is a challenging problem in free breathing undersampled cardiac perfusion magnetic resonance images. It is due to aliasing artifacts in the reconstructed images and the rapid contrast changes in the perfusion images. In addition to the reconstruction limitations, many registration algorithms underperforms in the presence of the rapid intensity changes. In this paper, we propose a novel motion correction technique that reconstructs the motion-free images from the undersampled cardiac perfusion MR data. The technique utilizes the robust principal component analysis along with the periodic decomposition to separate the respiratory motion component that can be registered, from the unchanged contrast intensity variations. It was tested on synthetic data, simulated data, and the clinically acquired data. The performance of the method was qualitatively assessed and validated by comparing manually acquired time–intensity curves of the myocardial sectors to automatically generated curves before and after registration. 相似文献
37.
Ali M. Haseeb Mustafa Keskin Ian L. Pegg Paul H. E. Meijer 《Fluid Phase Equilibria》1996,120(1-2):93-105
We describe a method to determine tielines for a mixture with a given volume Vt and a given mole fraction xt at fixed temperature, which is based on the orientation of the tangent plane to the Helmholtz free energy surface. The method works equally well for gas-liquid separation as for liquid-liquid separation. The method is based on a rotation in coordinate space followed by a rotation in function space which establishes the correct direction and the end points of the tieline. The mathematics is described and the general outline of a computer program to implement the method is given. This is followed by an application to a special form of the van der Waals equation, which describes the influence of chain-molecules as proposed by Tompa. The example given shows a three phase separation and the influence of the chain-length thereupon. 相似文献
38.
Muzamil Shah Hasnain Jan Samantha Drouet Duangjai Tungmunnithum Jafir Hussain Shirazi Christophe Hano Bilal Haider Abbasi 《Molecules (Basel, Switzerland)》2021,26(4)
Silybum marianum (L.) Gaertn is a rich source of antioxidants and anti-inflammatory flavonolignans with great potential for use in pharmaceutical and cosmetic products. Its biotechnological production using in vitro culture system has been proposed. Chitosan is a well-known elicitor that strongly affects both secondary metabolites and biomass production by plants. The effect of chitosan on S. marianum cell suspension is not known yet. In the present study, suspension cultures of S. marianum were exploited for their in vitro potential to produce bioactive flavonolignans in the presence of chitosan. Established cell suspension cultures were maintained on the same hormonal media supplemented with 0.5 mg/L BAP (6-benzylaminopurine) and 1.0 mg/L NAA (α-naphthalene acetic acid) under photoperiod 16/8 h (light/dark) and exposed to various treatments of chitosan (ranging from 0.5 to 50.0 mg/L). The highest biomass production was observed for cell suspension treated with 5.0 mg/L chitosan, resulting in 123.3 ± 1.7 g/L fresh weight (FW) and 17.7 ± 0.5 g/L dry weight (DW) productions. All chitosan treatments resulted in an overall increase in the accumulation of total flavonoids (5.0 ± 0.1 mg/g DW for 5.0 mg/L chitosan), total phenolic compounds (11.0 ± 0.2 mg/g DW for 0.5 mg/L chitosan) and silymarin (9.9 ± 0.5 mg/g DW for 0.5 mg/L chitosan). In particular, higher accumulation levels of silybin B (6.3 ± 0.2 mg/g DW), silybin A (1.2 ± 0.1 mg/g DW) and silydianin (1.0 ± 0.0 mg/g DW) were recorded for 0.5 mg/L chitosan. The corresponding extracts displayed enhanced antioxidant and anti-inflammatory capacities: in particular, high ABTS antioxidant activity (741.5 ± 4.4 μM Trolox C equivalent antioxidant capacity) was recorded in extracts obtained in presence of 0.5 mg/L of chitosan, whereas highest inhibitions of cyclooxygenase 2 (COX-2, 30.5 ± 1.3 %), secretory phospholipase A2 (sPLA2, 33.9 ± 1.3 %) and 15-lipoxygenase (15-LOX-2, 31.6 ± 1.2 %) enzymes involved in inflammation process were measured in extracts obtained in the presence of 5.0 mg/L of chitosan. Taken together, these results highlight the high potential of the chitosan elicitation in the S. marianum cell suspension for enhanced production of antioxidant and anti-inflammatory silymarin-rich extracts. 相似文献
39.
Nosheen Akhtar Noshin Ilyas Humaira Yasmin R. Z. Sayyed Zuhair Hasnain Elsayed A. Elsayed Hesham A. El Enshasy 《Molecules (Basel, Switzerland)》2021,26(6)
Plant growth-promoting rhizobacteria (PGPR) mediate heavy metal tolerance and improve phytoextraction potential in plants. The present research was conducted to find the potential of bacterial strains in improving the growth and phytoextraction abilities of Brassica nigra (L.) K. Koch. in chromium contaminated soil. In this study, a total of 15 bacterial strains were isolated from heavy metal polluted soil and were screened for their heavy metal tolerance and plant growth promotion potential. The most efficient strain was identified by 16S rRNA gene sequencing and was identified as Bacillus cereus. The isolate also showed the potential to solubilize phosphate and synthesize siderophore, phytohormones (indole acetic acid, cytokinin, and abscisic acid), and osmolyte (proline and sugar) in chromium (Cr+3) supplemented medium. The results of the present study showed that chromium stress has negative effects on seed germination and plant growth in B. nigra while inoculation of B. cereus improved plant growth and reduced chromium toxicity. The increase in seed germination percentage, shoot length, and root length was 28.07%, 35.86%, 19.11% while the fresh and dry biomass of the plant increased by 48.00% and 62.16%, respectively, as compared to the uninoculated/control plants. The photosynthetic pigments were also improved by bacterial inoculation as compared to untreated stress-exposed plants, i.e., increase in chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid was d 25.94%, 10.65%, 20.35%, and 44.30%, respectively. Bacterial inoculation also resulted in osmotic adjustment (proline 8.76% and sugar 28.71%) and maintained the membrane stability (51.39%) which was also indicated by reduced malondialdehyde content (59.53% decrease). The antioxidant enzyme activities were also improved to 35.90% (superoxide dismutase), 59.61% (peroxide), and 33.33% (catalase) in inoculated stress-exposed plants as compared to the control plants. B. cereus inoculation also improved the uptake, bioaccumulation, and translocation of Cr in the plant. Data showed that B. cereus also increased Cr content in the root (2.71-fold) and shoot (4.01-fold), its bioaccumulation (2.71-fold in root and 4.03-fold in the shoot) and translocation (40%) was also high in B. nigra. The data revealed that B. cereus is a multifarious PGPR that efficiently tolerates heavy metal ions (Cr+3) and it can be used to enhance the growth and phytoextraction potential of B. nigra in heavy metal contaminated soil. 相似文献
40.
Hasnain Mehmood Zahoor Ahmad Humaira M. Siddiqi Asma Iqbal Shahid Hameed 《Molecular Crystals and Liquid Crystals》2018,664(1):14-23
A series of ethyl 4-((4-alkoxyphenyl)diazenyl)benzoate is synthesized and the liquid crystalline behavior studied. Synthesized compounds are characterized by FTIR, 1H-NMR, Mass and single crystal XRD. Differential scanning calorimetry was carried out to study the phase transitions and enthalpy changes. Polarizing optical microscopy revealed the mesogenic properties. These techniques revealed that three compounds (2a, 2b, 2f) exhibit liquid crystalline properties in the range of 80–104°C. POM exhibiting focal conical fan like texture which revealed the presence of smectic phases suggestive of their use in LCD and temperature sensing devices, besides 2c can be used as green emitter in OLEDs. 相似文献