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991.
Macromorphological and micromorphological seed features of selected taxa of Caesalpiniaceae using light and scanning electron microscopy 总被引:1,自引:0,他引:1
Farhat Ullah Mushtaq Ahmad Muhammad Zafar Asma Jabeen Shazia Sultana Abdul Ghani Muhammad Luqman Moona Nazish Fakhre Alam 《Microscopy research and technique》2019,82(7):1073-1082
Seed micromorphological and macromorphological characteristics of 12 taxa of Caesalpiniaceae from Pakistan have been studied, using light and scanning electron microscopy, to investigate the importance of seed coat features as a taxonomic tool. Great variations have been observed in color, shape, dimension, and seed surface pattern among the different genera of the family. A taxonomic key was prepared for the studied taxa. Six types of seed shapes were observed; circular, elliptical, irregular, oblong, oval, and ovoid. All examined seeds were hard except fragile seeds of Haematoxylom campechianum. Eight types of surface ornamentation have been noticed that include levigate, lugose, papillate, reticulate, reticulate irregular, reticulate regular, rhombus, and rogues. Majority of the taxa has been observed with thick ornamentation wall but thin ornamentation wall has also been recorded in few species. Fracture line of the various patterns was present in all taxa except genus Bauhinia. Three types of texture crudeness; coarse, medium, and fine have been recorded. Both micromorphological and macromorphological characters of seed are very fruitful in identification and classification of Caesalpiniaceae. 相似文献
992.
Hoon‐Seok Jang Mannan Saeed Muhammad Tae‐Sun Choi 《Microscopy research and technique》2019,82(3):224-231
The consideration of the noise that affects 3D shape recovery is becoming very important for accurate shape reconstruction. In Shape from Focus, when 2D image sequences are obtained, mechanical vibrations, referred as jitter noise, occur randomly along the z‐axis, in each step. To model the noise for real world scenarios, this article uses Lévy distribution for noise profile modeling. Next, focus curves acquired by one of focus measure operators are modeled as Gaussian function to consider the effects of the jitter noise. Finally, since conventional Kalman filter provides good output under Gaussian noise only, a modified Kalman filter, as proposed method, is used to remove the jitter noise. Experiments are carried out using synthetic and real objects to show the effectiveness of the proposed method. 相似文献
993.
Shahzad Akbar Muhammad Sharif Muhammad Usman Akram Tanzila Saba Toqeer Mahmood Mahyar Kolivand 《Microscopy research and technique》2019,82(2):153-170
Retina is the interior part of human's eye, has a vital role in vision. The digital image captured by fundus camera is very useful to analyze the abnormalities in retina especially in retinal blood vessels. To get information of blood vessels through fundus retinal image, a precise and accurate vessels segmentation image is required. This segmented blood vessel image is most beneficial to detect retinal diseases. Many automated techniques are widely used for retinal vessels segmentation which is a primary element of computerized diagnostic systems for retinal diseases. The automatic vessels segmentation may lead to more challenging task in the presence of lesions and abnormalities. This paper briefly describes the various publicly available retinal image databases and various machine learning techniques. State of the art exhibited that researchers have proposed several vessel segmentation methods based on supervised and supervised techniques and evaluated their results mostly on publicly datasets such as digital retinal images for vessel extraction and structured analysis of the retina. A comprehensive review of existing supervised and unsupervised vessel segmentation techniques or algorithms is presented which describes the philosophy of each algorithm. This review will be useful for readers in their future research. 相似文献
994.
Wajid Zaman Syed Nasar Shah Fazal Ullah Asma Ayaz Mushtaq Ahmad Ashaq Ali 《Microscopy research and technique》2019,82(4):459-465
In present study, multiple microscope techniques were used for the systematics identification of the species Asplenium dalhousiae. The plant was collected from different phytogeographical and its natural habitat of Pakistan, where it shows higher diversity. Morphology, foliar epidermal anatomy, and spore morphological characters of the species were studied in detailed using multiple microscopic techniques through light microscopy (LM) and scanning electron microscopy (SEM). LM and SEM were used for the systematics identification of the species. Traditionally, the species is used in the ailment of many diseases, so the spore morphology, anatomical features, and morphological characters are relevant to describe the species taxonomy. The importance of multiple methods of taxonomic study (e.g., documentation and morphological characteristics) for characterizing herbs are important step in systematic certification to maintain the efficacy of herbal medicines. The aim of the present study is to examine the morphological, anatomical, and spore morphology of the species A. dalhousiae in more detailed for the correct taxonomic identification and their medicinal validation from Pakistan. 相似文献
995.
Nezahat Kandemir Ali elik Fazal Ullah Syed Nasar Shah Wajid Zaman 《Microscopy research and technique》2019,82(6):764-774
Iris L. is one of the important genus of family Iridaceae, consist of 56 taxa naturally occurred in Turkey. The similarities and variations in the subgenus overlapping the taxonomic positions of the species in the subgenera and needs anatomical assessment especially by microscopic techniques. In this study, the taxonomic significance of leaf anatomical characters of 10 Iris subgenus Scorpiris taxa were studied in detail and the relationship among these taxa were evaluated using microscopy techniques. Fresh leaf samples of species were fixed in 70% alcohol solution for anatomical observation under microscope. Eleven different micromorphological features were statistically analyzed to delimit the species in subgenus. Based on morphological and anatomical similarities, we studied relationships among; (1) ssp. turcica, ssp. caucasica, I. nezahatiae and I. pseudocaucasica; (2) correlation between ssp. turcica and ssp. caucasica; (3) association of I. galatica, I. persica, ssp. margaretiae and ssp. stenophylla with each other; (4) relationship between ssp. stenophylla and ssp. margaretiae; and (5) relevance between I. aucheri and I. peshmeniana. Moreover, the taxonomy of subgenus Scorpiris has been discussed in detail with novel and diagnostic features based on micromorphological physiognomies. We found that four species in this study are endemic to Turkey, while seven are critically endangered geophytes in the country. The leaf anatomical characteristics of 10 taxa were divided into three groups. Main aim of this research was to study the taxonomy of the complex subgenus Scorpiris through microscopic techniques. 相似文献
996.
Saddam Saqib Muhammad Farooq Hussain Munis Wajid Zaman Fazal Ullah Syed Nasar Shah Asma Ayaz Muhammad Farooq Saraj Bahadur 《Microscopy research and technique》2019,82(4):415-420
In this decade, the use of nano particles (NPs) against bacterial growth is increasing day by day due to remarkable alternative properties compared to molecular antibiotics. Thus, the use of iron oxide nanoparticles (IONPs) has proven one of the most important transition metals oxide‐based remedy in nanotechnological advances and biological applications due to enriched biocompatibility of iron. In this study synthesis of IONPs was carried out via co‐precipitation method. The crystallographic morphology of the synthesized particles was studied via X‐ray diffraction which revealed cubic structure of the particles, whereas, the spinal shaped morphology of the prepared NPs was confirmed from scanning electron microscopy. Likewise, the presence of the major elements in the sample was determined through energy dispersive X‐ray analysis characterization. Bactericidal effect of the NPs was assessed at pre‐defined concentrations (50 and 100 μg/ml) against Gram +ve bacteria Staphylococcus aureus, Gram ?ve bacteria Shigella dysentry and Escherichia coli . Bacterial strains, which demonstrate the potential of NPs. The purpose of this study was assessing the structure of the synthesized NPs for protective effect against harmful bacterial activity. 相似文献
997.
Syed N. Shah Mushtaq Ahmad Muhammad Zafar Fazal Ullah Wajid Zaman Khafsa Malik Neelam Rashid Saba Gul 《Microscopy research and technique》2019,82(8):1326-1333
Spore morphology of Thelypteridaceae species growing in Malakand Division, Northern Pakistan, was studied using both light microscopy and scanning electron microscopy. The taxa are Christella dentata and Glaphyropteridopsis erubescens in the subfamily Thelypteridoideae, and Phegopteris connectilis, Pseudophegopteris pyrrhorhachis, and Pseudophegopteris levingei in the subfamily Phegopteridoideae. The studied species exhibit differences in spore size, exospore thickness, color, and ornamentation. Spores of the studied species are monolete and medium‐sized, and shape is ellipsoidal in both polar and equatorial views. The average measurement of the polar diameter ranges from 27 μm to 31 μm, whereas in the equatorial direction it varied from 20 μm to 40 μm. The exospore thickness ranges from 1.2 μm to 2.4 μm. Reticulate, laevigate with microgranules, cristate, and coarsely echinate surface ornamentation are observed among the species. Multivariate analysis including unweighted pair group method with arithmetic mean and principal component analysis was used for the grouping and discrimination of species and genera. 相似文献
998.
Ali Aakash Nasir Muhammad Ali Khalid Muhammad Yasir Nauman Saad Shaker Khubab Khushnood Shahab Altaf Khurram Zeeshan Muhammad Hussain Azhar 《Journal of Mechanical Science and Technology》2019,33(9):4217-4226
Journal of Mechanical Science and Technology - Natural fiber composites have great potential for reducing the product cost, lowering weight and enhancing renewability. Functionality and performance... 相似文献
999.
Recent developments in nanotechnology provided an opportunity to solve many complex problems in the field of energy. Performance investigation of the nanoscale thermal cycles can prove crucial in the development of efficient and less polluting energy system. Due to the influence of boundary phenomenon and quantum degeneracy effects, a nanoscale engine performs according to statistical quantum thermodynamics instead of classical thermodynamics. In this study, a nanoscale Stirling engine operating on an ideal Maxwell‐Boltzmann gas is investigated for multiobjective optimization. Optimization problem of Stirling cycle is formed considering the thermal efficiency, ecological coefficient of performance and entropy generation. An application example of a nanoscale Stirling engine is presented and solved using Heat Transfer Search algorithm. Maxwell‐Boltzmann gas restricted in a finite domain is studied and the effect of different parameters, such as surface area ratio, volume ratio, and temperature ratio of the domain, is investigated. Sensitivity analysis is carried out to identify the effect of design variables on the performance parameters. Further, influence of the source temperature and the number of particles of working fluid on the objective functions is studied and presented. 相似文献
1000.
Jing Zhang Muhammad Kamran Siddiqui Waqas Nazeer 《Petroleum Science and Technology》2019,37(4):430-435
A series of experiments have been performed to investigate the influence of reaction temperature, the equivalence ratio (ER), and blending ratio on the gas composition, tar content and higher heating value (HHV) of synthesis gas. H2 content decreased from 10.7 to 8.2% in the range of BR while CO and CH4 increased from 17.4 to 23.1% and 3.4 to 6.3%, respectively. HHV increased with BR and H2/CO showed an opposite trend. The highest HHV and H2/CO were obtained at 100%PW and 100%OS, respectively. Tar content increased from 4.8 to 9.5?g/Nm3 with BR increasing in the range because of a reduction in the endothermic nature of volatile combustion. 相似文献