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991.
Sofia Rashid Muhammad Zafar Mushtaq Ahmad Muhammad Ibrar Shinwari Ghulam Yaseen Shazia Sultana Rabia Asma Memon Syeda Alia Zehra Puto Agus Hendra Wibawa 《Microscopy research and technique》2019,82(6):731-740
The study is aimed to provide a comprehensive account on authentication of herbal drug named as Tukhm‐e‐balango (Lallemantia royleana Benth.) from the seeds of Ocimum basilicum by using microscopic, pharmacognostic, and phytochemical characterization. The crude medicinal plants and their parts are often adulterated or substituted in market due to improper identification by the consumers while among herbal plant sellers, taxonomic confusion is caused due to morphological similarities of the plant parts and lack of a standard identification system.In microscopy, both herbarium and fresh specimens were studied using qualitative and quantitative morphological characteristics of leaves, seeds, and pollen. For pharmacognosy, solubility, fluorescence, and physicochemical characterizers were analyzed whereas a total phenolic and flavonoids contents was determined in addition to DPPH radical scavenging activity. In current study, microscopic, pharmacognostic, and phytochemical characterization clearly differentiated L. royleana from O. basilicum. The major problem in herbal drug industry is caused due to confusion and controversy of certain synonyms used for more than one or two drugs. Sometimes, under the same common or local name, entirely different taxa are being sold in herbal markets. It is concluded that correct and proper identification of medicinal plants is very crucial to ensure the safety and efficacy of herbal medicines, as many medicinal plants are intentionally or unintentionally adulterated with similar species or varieties. In herbal market, the seeds of L. royleana are adulterated with seeds of O. basilicum due to their similar morphology. 相似文献
992.
Sofia Rashid Mushtaq Ahmad Muhammad Zafar Shazia Sultana Sidra Nisar Ahmad Ghulam Yaseen Fethi Ahmet Ozdemir Rabia Afza 《Microscopy research and technique》2019,82(7):1092-1101
Swertia cordata (G. Don) C.B. Clarke is one of the potential medicinal plants extensively used in eastern traditional medicine such as Unani, Ayurveda, Siddha, and in traditional Tibetan and Chinese medicine. S. paniculata is the common adulterant of S. cordata at herbal shops and markets but S. paniculata is also used in number of herbal formulations. The present study was conducted to use microscopic, pharmacognostic, and phytochemical techniques as a tool for the authentication of herbal drug chiraita (S. cordata). In herbal markets, mixing, adulteration, and use of spurious materials as substitute have become a major concern for herbal practitioners, local user, and industry for reasons of safety and efficacy. Therefore, authentication of medicinal plants is of utmost importance at each level of drug research. In the present study, anatomical features of two species showed a great diversity, as irregular epidermal cells and nonglandular, unicellular trichomes were found in S. cordata while in S. paniculata epidermal cells were hexagonal in shape and trichomes were A‐shaped. Antioxidant activity of two species showed a great variation where IC50 value recorded for S. cordata was 208 μg/mL, while for S. paniculata IC50 was 624 μg/mL. The study can serve as an important source of information to achieve the authenticity and to evaluate the quality and purity of the plant material in accordance to WHO guidelines. As this species is greatly exploited, so conservation is highly recommended. 相似文献
993.
Sajid Iqbal Muhammad U. Ghani Khan Tanzila Saba Zahid Mehmood Nadeem Javaid Amjad Rehman Rashid Abbasi 《Microscopy research and technique》2019,82(8):1302-1315
Automatic and precise segmentation and classification of tumor area in medical images is still a challenging task in medical research. Most of the conventional neural network based models usefully connected or convolutional neural networks to perform segmentation and classification. In this research, we present deep learning models using long short term memory (LSTM) and convolutional neural networks (ConvNet) for accurate brain tumor delineation from benchmark medical images. The two different models, that is, ConvNet and LSTM networks are trained using the same data set and combined to form an ensemble to improve the results. We used publicly available MICCAI BRATS 2015 brain cancer data set consisting of MRI images of four modalities T1, T2, T1c, and FLAIR. To enhance the quality of input images, multiple combinations of preprocessing methods such as noise removal, histogram equalization, and edge enhancement are formulated and best performer combination is applied. To cope with the class imbalance problem, class weighting is used in proposed models. The trained models are tested on validation data set taken from the same image set and results obtained from each model are reported. The individual score (accuracy) of ConvNet is found 75% whereas for LSTM based network produced 80% and ensemble fusion produced 82.29% accuracy. 相似文献
994.
Effect of Different Degree of Deacetylation,Molecular Weight of Chitosan and Palm Stearin and Palm Kernel Olein Concentration on Chitosan as Edible Packaging for Cherry Tomato
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996.
In case of a severe nuclear reactor accident, the core can melt and form a particulate debris bed in the lower plenum of the reactor pressure vessel (RPV). Due to the decay heat, the particle bed, if not cooled properly, can cause failure of the RPV. In order to avoid further propagation of the accident, complete coolability of the debris bed is necessary. For that, understanding of various phenomena taking place during the quenching is important. In the frame of the reactor safety research, fundamental experiments on the coolability of debris beds are carried out at IKE with the test facility “DEBRIS”. In the present paper, the boiling and dry-out experimental results on a particle bed with irregularly shaped particles mixed with stainless steel balls have been reported. The pressure drops and dry-out heat fluxes of the irregular-particle bed are very similar to those for the single-sized 3 mm spheres bed, despite the fact that the irregular-particle bed is composed of particles with equivalent diameters ranging from 2 to 10 mm. Under top-flooding conditions, the pressure gradients are all smaller than the hydrostatic pressure gradient of water, indicating an important role of the counter-current interfacial drag force. For bottom-flooding with a liquid inflow velocity higher than about 2.7 mm/s, the pressure gradient generally increases consistently with the vapour velocity and the fluid-particle drag becomes important. The system pressures (1 and 3 bar) have negligible effects on qualitative behaviour of the pressure gradients. The coolability of debris beds is mainly limited by the counter-current flooding limit (CCFL) even under bottom-flooding conditions with low flow rates. The system pressure and the flow rate are found to have a distinct effect on the dry-out heat flux.Different classical models have been used to predict the pressure drop characteristics and the dry-out heat flux (DHF). Comparisons are made among the models and experimental results for DHF and pressure drop characteristics. Considering the overall trend in prediction of DHF and two-phase pressure drop, it was observed that none of the models could provide accurate predictions for both DHF and pressure drop under top- and bottom-flooding conditions. This implies that developments of more accurate models are needed including the effects of non-uniform particle sizes and the multidimensional nature of particulate debris beds, which are not reflected so far in these models. 相似文献
997.
Alireza Naji Givi Suraya Abdul Rashid Farah Nora A. Aziz Mohamad Amran Mohd Salleh 《Composites Part B》2010,41(8):673-677
In the current study, the size effects of SiO2 nano-particles on compressive, flexural and tensile strength of binary blended concrete were investigated. SiO2 nano-particles with two different sizes of 15 and 80 nm have been used as a partial cement replacement by 0.5, 1.0, 1.5 and 2.0 wt.%. It was concluded that concrete specimens containing SiO2 particles with average diameter of 15 nm were harder than those containing 80 nm of SiO2 particles at the initial days of curing. But this condition was altered at 90 days of curing. Also from the viewpoint of free energy, it can be concluded that the C–S–H gel formation around the particles with average diameter of 15 nm was more at the primary days of curing. This can be as a result of more nucleation sites that causes acceleration in early age strength. On the other hand, the growth probability of C–S–H gel around the 80 nm particles was more at 90 days of moist curing. This is due to the fact that the nucleus of strengthening gel could simply reach to the critical volume of nucleation that causes increase in the strength. 相似文献
998.
999.
Analysis and Provision of QoS for Distributed Grid Applications 总被引:5,自引:0,他引:5
Rashid?J.?Al-AliEmail author Kaizar?Amin Gregor?von?Laszewski Omer?F.?Rana David?W.?Walker Mihael?Hategan Nestor?Zaluzec 《Journal of Grid Computing》2004,2(2):163-182
Grid computing provides the infrastructure necessary to access and use distributed resources as part of virtual organizations. When used in this way, Grid computing makes it possible for users to participate in collaborative and distributed applications such as tele-immersion, visualization, and computational simulation. Some of these applications operate in a collaborative mode, requiring data to be stored and delivered in a timely manner. This class of applications must adhere to stringent real-time constraints and Quality-of-Service (QoS) requirements. A QoS management approach is therefore required to orchestrate and guarantee the timely interaction between such applications and services. We discuss the design and a prototype implementation of a QoS system, and demonstrate how we enable Grid applications to become QoS compliant. We validate this approach through a case study of an image processing task derived from a nanoscale structures application. 相似文献
1000.