Wyniki wyszukiwania - Biblioteka Nauki

1

Mutagenic effectiveness and efficiency of gamma rays and HZ with phenotyping of induced mutations in lentil cultivars

100%

Laskar R. M. , Khan S.

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tom 64

EN

In mutation breeding, mutagenic effectiveness and efficiency are the base parameters to predict the mutagenic potency of any mutagen. Studies on mutagenic effectiveness and mutagenic efficiency of physical mutagen (gamma rays) and chemical mutagen (hydrazine hydrates; HZ) on two cultivars of lentil (Lens culinaris Medik.), viz. DPL 62 (macrosperma) and Pant L 406 (microsperma) have been reported. Dry and healthy seeds were treated with four doses of each gamma rays (100-400 Gy), HZ (0.1-0.4 %) and their combinations. Frequencies of the induced agro-morphological variations into different phenotypic categories were estimated in M2 population that resulted into identification and isolation of wide range of mutants with altered phenotypes. Data on effectiveness and efficiency of various mutagenic treatments calculated on the basis of the frequency of chlorophyll mutations, which showed effectiveness and efficiency were higher at the moderate doses of gamma rays and HZ, while in case of combination treatments; lower doses were most effective and efficient with few inter-varietal exceptions. Phenotyping of the mutants revealed that growth habits was the most sensitive category to which most of the mutant belongs, followed by leaf and flower/pod/seed in both the cultivars studied. Overall, the screened and isolated mutants with economically important agronomic traits can be further propagated in the subsequent generation for development of elite lentil mutant cultivars.

2

Generating relations involving hypergeometric functions by means of integral operators

100%

Pathan M. , Khan S.

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2002

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tom Vol. 35, nr 1

35-39

EN

In this paper, the focus is on the results which involve exponential functions. The results of Pathan and Yasmeen [6] and Exton [3] are used with a view to obtaining generating functions which are partly unilateral and partly bilateral.

3

Induce physical and chemical mutagenesis for improvement of yield attributing traits and their correlation analysis in Chickpea

85%

Raina A. , Laskar R. A. , Khursheed S. , Khan S. , Parveen K. , Amin R. , Khan S.

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tom 61

EN

In the current scenario of sky high population and widespread food insecurity, there is an urgent need for productivity improvement of major crops like pulses, one of the most climate friendly and accessible foods for the large poor population of the world. Chickpea is an important pulse crop, having high percentage of nutritional content and is widely used as food across the world. Induced mutagenesis has proved over time as a coherent tool for modern plant breeders to improve the productivity for combating the food insecurity and malnutrition across the globe. Dry and healthy seeds of Cicer arietinum L. var. C-235 were treated with individual and combination doses of gamma rays, sodium azide and hydrazine hydrate to raise the M₁ generation. M₂ seeds harvested from M₁ plants were sown in the nest season. Bio-physiological study in M1 generation showed growth inhibition in the order viz. combination treatment>hydrazine hydrate>gamma rays>sodium azide. In M₂ generation, comparative observations were recorded for morphological variation and quantitative traits to assess the genetic response of the chickpea variety C-235 toward the different concentrations of mutagens. Observations on isolated mutants in M₂ generation revealed that 0.3% HZ + 0.02% SA was most mutagenic while 200 Gy, 0.03% SA and 0.2% HZ were highest in their individual treatment groups. In context to the frequency of morphological mutants studied in M₂ generation, dwarf mutants were found to be highest followed by tall and branching pattern mutants. Highly significant correlation coefficient between yield and other traits showed that the selection for high yielding mutants can be done on the basis of these traits undoubtedly.

4

Carbon Emissions, Energy Use, Gross Domestic Product and Total Population in China

85%

Ahmad M. , Hengyi H. , Rahman Z. U. , Khan S. , Khan S. , Khan Z.

Ekonomia i Środowisko

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2018

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nr 2[65]

5

Characterization of the Hammamet basin aquifer (North-East of Algeria) through geochemical and geostructural methods and analysis

80%

Chelih F. , Fehdi C. , Khan S.

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2018

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nr 37

6

Atmospheric influences on satellite communications

80%

Zubair M. , Haider Z. , Khan S. , Nasir J.

Przegląd Elektrotechniczny

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2011

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tom R. 87, nr 5

261-264

EN

Among other atmospheric regions, ionosphere, which is ionized region of the atmosphere, is considered to impose serious limitations on satellite communication. At higher frequencies, radio waves pass through the ionosphere and are attenuated due to the free electrons present in ionosphere. This paper discusses atmospheric effects on high frequency radio waves illustrating the attenuation and losses it may come across like attenuation due to atmospheric gases, rain, clouds, beam spreading loss and noise temperature. Data used to summarize the influence of atmospheric phenomena is obtained from ITU-R models and processed using MATLAB.

PL

Spośród różnych warstw atmosfery szczególnie jonosfera wpływa niekorzystnie na komunikację za pośrednictwem satelitów. Przy wyższych częstotliwościach fale radiowe są silnie tłumione w jonosferze. Artykuł przedstawia analizę wpływu czynników atmosferycznych w jonosferze na tłumienie i straty w radiowej komunikacji wysokoczęstotliwościowej.

7

Coumaroyl Adenosine and Lignan Glycoside from Amaranthus spinosus L

80%

Azhar-ul-Haq , Malik A. , Khan S. , Muhammad P.

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2006

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tom Vol. 80, nr 2

259-263

EN

Phytochemical investigation of the n-butanol fraction of the methanolic extract of the whole plant of Amaranthus spinosus Linn. led to the isolation of amaranthoside, a lignan glycoside 1, and amaricin, a coumaroyl adenosine 2 along with stigmasterol glycoside 3. The structures of these compounds were determined by spectral analysis (including 1Dand 2D-NMR experiments) and comparison with literature data.

8

Nickel toxicology with reference to male molecular reproductive physiology

80%

Rizvi A. , Parveen S. , Khan S. , Naseem I.

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tom 20

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nr 1

9

Effects of ultra-violet radiation on cellular proteins and lipids of radioresistant bacteria isolated from desert soil

71%

Sajjad W. , Khan S. , Ahmad M. , Rafiq M. M. , Badshah M. , Sajjad W. , Zada S. , Khan S. , Hasan F. , Shah A. A.

Folia Biologica

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2018

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tom 66

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nr 1

10

In search of a potential diagnostic tool for molecular characterization of lymphatic filariasis

71%

Saeed M. , Adnan M. , Khan S. , Al-Shammari E. , Mustafa H.

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tom 61

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nr 1

11

Role of aquaporins in plant responses to root hypoxia

61%

Zwiazek J. J. , Tan X. , Xu H. , Khan S. , Equiza M. A. , Lee S. H. , Vaziriyeganeh M.

Acta Physiologiae Plantarum

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2018

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tom 40

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nr 11-11th International Conference Plant Functioning under Environmental Stress...

12

Carbon emissions, energy use, gross domestic product and total population in China

61%

Ahmad M. , Hengyi H. , Rahman Z. U. , Khan Z. U. , Khan S. , Khan Z.

Ekonomia i Środowisko

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2018

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tom nr 2

32--44

EN

The current study explores the impact of energy consumption, total population, gross domestic product on carbon emissions by utilizing time series data of 1971-2013 for China. Earlier studies concentrated on testing the present form of an environmental Kuznets curve not taking total population in a model. Specifically, this study focuses on analyzing the long run existence of environmental Kuznets curve. The methodology of auto regressive distributed lag model is utilized. The quadratic linkage between national income and emissions of carbon have been detected, confirming the presence of long run linkage between quadratic national income and emissions of carbon. Granger causality test divulge one-way causality between gross domestic product and carbon emissions. The empirical findings also reveal that the energy use and national income are important factors of carbon emanations in the long run. Total population has an insignificant positive influence on emissions of carbon. It is suggested that government should focus to extract that substitute sources of energy which is more environmental friendly.

13

HMG-CoA reductase limits artemisinin biosynthesis and accumulation in Artemisia annua L. plants

51%

Ram M. , Khan M. A. , Jha P. , Khan S. , Kiran U. , Ahmad M. M. , Javed S. , Abdin M. Z.

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nr 5

EN

In vivo modulation of HMG-CoA reductase (HMGR) activity and its impact on artemisinin biosynthesis as well as accumulation were studied through exogenous supply of labeled HMG-CoA (substrate), labeled MVA (the product), and mevinolin (the competitive inhibitor) using twigs of Artemisia annua L. plants collected at the preflowering stage. By increasing the concentration (2–16 µM) of HMG-CoA (3-¹⁴C), incorporation of labeled carbon into artemisinin was enhanced from 7.5 to 17.3 nmol (up to 130%). The incorporation of label (¹⁴C) into MVA and artemisinin was inhibited up to 87.5 and 82.9%, respectively, in the presence of 200 µM mevinolin in incubation medium containing 12 µM HMG-CoA (3-¹⁴C). Interestingly, by increasing the concentration of MVA (2-¹⁴C) from 2 to 18 µM, incorporation of label (¹⁴C) into artemisinin was enhanced from 10.5 to 35 nmol (up to 233%). When HMG-CoA (3-¹⁴C) concentration was increased from 12 to 28 µM in the presence of 150 µM mevinolin, the inhibitions in the incorporation of label (¹⁴C) into MVA and artemisinin were, however, reversed and the labels were found to approach their values in twigs fed with 12 µM HMG-CoA (3-¹⁴C) without mevinolin. In another experiment, 14.2% inhibition in artemisinin accumulation was observed in twigs in the presence of 175 µM fosmidomycin, the competitive inhibitor of 1-deoxy-D-xylulose 5-phosphate reductase (DXR). HMG-CoA reductase activity and artemisinin accumulation were also increased by 18.6 to 24.5% and 30.7 to 38.4%, respectively, after 12 h of treatment, when growth hormones IAA (100 ppm), GA₃ (100 ppm) and IAA + GA₃ (50 + 50 ppm) were sprayed on A. annua plants at the pre-flowering stage. The results obtained in this study, hence, demonstrate that the mevalonate pathway is the major contributor of carbon supply to artemisinin biosynthesis and HMGR limits artemisinin synthesis and its accumulation in A. annua plants.

14

Adsorption characteristics of magnesium-modified bentonite clay with respect to acid blue 129 in aqueous media

51%

Hussain S. , Ullah Z. , Gul S. , Khattak R. , Kazmi N. , Rehman F. , Khan S. , Ahmad K. , Imad M. , Khad A.

Polish Journal of Environmental Studies

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2016

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tom 25

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nr 5

EN

Locally available bentonite clay has been modified by magnesium and used to eliminate acid blue 129 from aqueous solutions. The adsorption was studied under different experimental conditions such as dye concentrations, temperature, and shaking time. The adsorption of the dye increased with time and followed the pseudo-first-order kinetic with rate constant “k” 0.126 min-1 at 283 K. Thermodynamic parameters such as ΔH°, ΔS°, and ΔG° were calculated from the slope and intercept of the linear plots of ln K against1/T. Analysis of adsorption results obtained at temperatures of 283, 293, 303, and 313 K showed that the adsorption pattern on bentonite seems to follow Langmuir and Freundlih. The increase in temperature reduces adsorption capacity by magnesium-modified bentonite due to the enhancement of the desorption step in the mechanism. The activation energy of the adsorption process was found to be 3.55 kJ mol-1. The Mg-bentonite showed better adsorption than Ba and Al-bentonite. Our study reveals that abundantly available local clay may be used to eliminate dyes from aqueous solutions.

15

Invasion impact analysis of Broussonetia papyrifera in Pakistan

51%

Qureshi H. , Anwar T. , Fatima S. , Akhtar S. , Khan S. , Wassem M. , Mohibullah M. , Shirani M. , Riaz S. , Azeem M.

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nr 4

16

Detection of ECG T-wave Alternans Using Maxima of Continuous-Time Wavelet Transform Ridges

51%

Bakhshi A. D. , Ahmed A. , Gulfam S. , Khaqan A. , Yasin A. , Riaz R. , Alimgeer K. , Malik S. , Khan S. , Dar A. H.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 12b

35-38

EN

Prognostic utility of microvolt T-wave alternans (TWA) has been established since its clinical acceptance as marker for malignant ventricular arrhythmias, leading to sudden cardiac death. Accurate detection of TWA from surface ECG is a challenge because of invisible nature of the phenomenon. A novel TWA detection scheme based upon analysis of continuous time wavelet ridges (CTWR) of consecutive ventricular repolarization complexes is presented. The CTWR is computed using maxima of wavelet energy coefficients of continuous wavelet transform. Variety of simulated alternans waveforms, wavelet functions, frequency bands and noise levels are used to test the algorithm. The study concludes that CTWR can successfully characterize the alternation of cardiac repolarization and detect TWA phenomenon.

PL

Diagnostyka sygnału TWA odgrywa dużą rolę w badaniach jako marker arytmii powodującej zawał serca. Sygnał TWA jest wykrywany jako składowa sygnału elektrokardiogramu. W artykule opisano wykorzystanie ciągłej transformaty falkowej do analizy tego sygnału. (Detekcja składowej TWA sygnału EKG bazująca na wykorzystaniu ciągłej transformaty falkowej)

17

Phytochemical screening of Pulsatilla species and investigation of their biological activities

51%

Laska G. , Sienkiewicz A. , Stocki M. , Zjawiony J. K. , Sharma V. , Bajguz A. , Piotrowska-Niczyporuk A. , Jacob M. , Khan S.

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tom 88

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nr 1

EN

The present study aimed to identify biologically active secondary metabolites from the rare plant species, Pulsatilla patens subsp. patens and the cultivated P. vulgaris subsp. vulgaris. Chromatographic fractionation of the ethanolic extract of the roots of P. patens subsp. patens resulted in the isolation of two oleanane-type glycosides identified as hederagenin 3-O-β-d-glucopyranoside (2.7 mg) and hederagenin 3-O-β-d-galactopyranosyl-(1→2)-β-d-glucopyranoside (3.3 mg, patensin). HPLC analysis of the methanolic extract of the crude root of P. patens subsp. patens and P. vulgaris subsp. vulgaris revealed the presence of Pulsatilla saponin D (hederagenin 3-O-α-l-rhamnopyranosyl(1→2)-[β-d-glucopyranosyl(1→4)]-α-l-arabinopyranoside). Chromatographic analysis using GC-MS of the silylated methanolic extracts from the leaves and roots of these species identified the presence of carboxylic acids, such as benzoic, caffeic, malic, and succinic acids. The extracts from Pulsatilla species were tested for their antifungal, antimicrobial, and antimalarial activities, and cytotoxicity to mammalian cell lines. Both P. patens subsp. patens and P. vulgaris subsp. vulgaris were active against the fungus Candida glabrata with the half-maximal inhibitory concentration (IC₅₀) values of 9.37 μg/mL and 11 μg/mL, respectively. The IC₅₀ values for cytotoxicity evaluation were in the range of 32–38 μg/mL for P. patens subsp. patens and 35–57 μg/mL for P. vulgaris subsp. vulgaris for each cell line, indicating general cytotoxic activity throughout the panel of evaluated cancer and noncancer cells.

18

Mechanism of insecticide resistance in insects/pests

41%

Khan S. , Uddin N. , Rizwan M. , Khan W. , Farooq M. , Shah A. S. , Subhan F. , Aziz F. , Rahman K. U. , Khan A. , Ali S. , Muhammad M.

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2020

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tom 29

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nr 3