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21.
Saba Gul Mushtaq Ahmad Muhammad Zafar Saraj Bahadur Shazia Sultana Najla Begum Syed Nasar Shah Wajid Zaman Fazal Ullah Asma Ayaz Uzma Hanif 《Microscopy research and technique》2019,82(7):1021-1031
The present study is insight into pollen morphology for characterizing species and their utility in the taxonomic separation of certain taxa of subfamily Nepetoideae (Lamiaceae) from Pakistan. The pollen micromorphology of 11 species of the Nepetoideae was analyzed and documented using light microscopy and scanning electron microscopy (SEM) for both qualitative and quantitative characteristics. Most species have hexazonocolpate pollen grains but trizonocolpate and tetrazonocolpate pollen with circular and oval amb were also rarely observed in Mentha spicata. The basic pollen shape in most of the studied species was subspheroidal but prolate grains were also observed in M. spicata, S. coccinea, and S. plebeia. The exine sculpturing of Nepetoideae pollen was taxonomically very informative particularly at subfamily level. Observations of exine sculpturing with SEM revealed various types of pollen grains: reticulate, bireticulate, microreticulate, perforate, aerolate, and gammate. The bireticulate type further subdivided into three subtypes based on the number of secondary lumina in each primary lumen and is characterized by varying characteristics of the secondary reticulum and primary muri. A significant variation was observed in colpus surface ornamentation. The maximum polar diameter was found in O. americanum (58 ± 5.8 μm) and the maximum equatorial diameter observed in O. basilicum (50.25 ± 1.37 μm). Pollen features of the studied species were discussed and compared based on the current taxonomical concepts. The results showed that pollen traits of the subfamily Nepetoideae was found significant to classify the taxa. Furthermore, pollen features provide additional evidence to distinguish macromorphologically similar taxa from each other. 相似文献
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Yesmin Ara Begum Pitambar Baishya Manas Jyoti Das Sourav Chakraborty Sankar Chandra Deka 《International Journal of Food Science & Technology》2020,55(11):3455-3462
Dietary fibre (DF)-anthocyanin formulation was incorporated in bread to develop anthocyanin rich DF powder (ARDFP) fortified bread. Prior to incorporation of DF-anthocyanin formulation in bread preparation, the cytotoxicity of DF and anthocyanin extracts was assessed. The effect of incorporation of different level of ARDFP with moisture on bread quality characteristics such as specific volume, textural, colour, sensory properties and starch digestibility was studied. The results revealed that extracted DF and anthocyanin of culinary banana bracts were nontoxic towards peripheral blood mononuclear cell and cytotoxic towards HT29 cancerous cell line. Incorporation of 2% ARDFP with 68% moisture was rated as best with higher specific volume (5.50 cm3 g−1), improved textural properties (high springiness and cohesiveness), anthocyanin content (9.08 mg per 100 g), colour characteristics and sensory acceptability next to control. The in vitro digestibility study suggested increased incorporation of ARDFP in bread flour reduced the rate of starch digestibility (0.0035 min−1). 相似文献
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Telecommunication Systems - In this paper, we derive upper bound of Packet Error Probability (PEP), upper bound of delay and lower bound of throughput in cognitive radio networks. Our analysis is... 相似文献
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Kassimi Fatima Zahrae Zaari Halima Benyoussef Abdelilah Rachadi Abdeljalil El Kenz Abdallah 《Journal of Superconductivity and Novel Magnetism》2022,35(9):2493-2503
Journal of Superconductivity and Novel Magnetism - Multiferroic oxide materials have attracted much intention in recent years due to their application in different fields such as magnetic... 相似文献
26.
Ethan S. Pickerill Rebecca P. Kurtz Aaron Tharp Paula Guerrero Sanz Munni Begum Douglas A. Bernstein 《Yeast (Chichester, England)》2019,36(11):669-677
RNA can be modified in over 100 distinct ways, and these modifications are critical for function. Pseudouridine synthases catalyse pseudouridylation, one of the most prevalent RNA modifications. Pseudouridine synthase 7 modifies a variety of substrates in Saccharomyces cerevisiae including tRNA, rRNA, snRNA, and mRNA, but the substrates for other budding yeast Pus7 homologues are not known. We used CRISPR-mediated genome editing to disrupt Candida albicans PUS7 and find absence leads to defects in rRNA processing and a decrease in cell surface hydrophobicity. Furthermore, C. albicans Pus7 absence causes temperature sensitivity, defects in filamentation, altered sensitivity to antifungal drugs, and decreased virulence in a wax moth model. In addition, we find C. albicans Pus7 modifies tRNA residues, but does not modify a number of other S. cerevisiae Pus7 substrates. Our data suggests C. albicans Pus7 is important for fungal vigour and may play distinct biological roles than those ascribed to S. cerevisiae Pus7. 相似文献
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Kure Halima Ibrahim Islam Shareeful Mouratidis Haralambos 《Neural computing & applications》2022,34(18):15241-15271
Neural Computing and Applications - Cyber security risk management plays an important role for today’s businesses due to the rapidly changing threat landscape and the existence of evolving... 相似文献
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A thermal vacuum evaporation system has been used to deposit zinc telluride (ZnTe) thin film on glass substrate in order to investigate the structural, morphological, optoelectronic and electrical properties of the deposited film. The deposited film has been characterised by X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-VIS-NIR spectrophotometer. The polycrystalline and cubic structure of the sample has been confirmed by XRD. The order parameter(s), which determines the crystallinity and good environmental stability of the sample, has been obtained for the peak (1 1 1) to peak (2 0 0) and is found to be 0.83. The XRD patterns and Bragg’s law have been examined to determine the microstructural parameters (lattice parameter, inter-planar spacing, crystallite size, number of crystallites per unit area, strain, dislocation density) of the investigated film. Optical properties (transmittance, absorbance, refractive index, absorption coefficient, extinction coefficient, optical density) of ZnTe thin film were extensively studied in incident photon energy range of 0.5–3.5 eV, where direct optical transition has been obtained with a band gap of 2.63 eV. The surface morphology of the evaporated ZnTe thin film has been checked by AFM. 相似文献
30.
Multimedia Tools and Applications - Optimal secure visual cryptography for brain MRI medical image is proposed in this paper. Initially, the brain MRI images are selected and then discrete wavelet... 相似文献