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61.
Muhammad Shafiq Xiangzhan Yu Ali Kashif Bashir Hassan Nazeer Chaudhry Dawei Wang 《The Journal of supercomputing》2018,74(10):4867-4892
Class imbalance has become a big problem that leads to inaccurate traffic classification. Accurate traffic classification of traffic flows helps us in security monitoring, IP management, intrusion detection, etc. To address the traffic classification problem, in literature, machine learning (ML) approaches are widely used. Therefore, in this paper, we also proposed an ML-based hybrid feature selection algorithm named WMI_AUC that make use of two metrics: weighted mutual information (WMI) metric and area under ROC curve (AUC). These metrics select effective features from a traffic flow. However, in order to select robust features from the selected features, we proposed robust features selection algorithm. The proposed approach increases the accuracy of ML classifiers and helps in detecting malicious traffic. We evaluate our work using 11 well-known ML classifiers on the different network environment traces datasets. Experimental results showed that our algorithms achieve more than 95% flow accuracy results. 相似文献
62.
Bashir Zia Malik M. G. Abbas Hussain Muhammad Iqbal Nadeem 《Multimedia Tools and Applications》2022,81(3):3867-3897
Multimedia Tools and Applications - For the asymmetric key, the Diffie Hellman Key (DHK) protocol is very efficient, but sometimes it is vulnerable against brute force attacks if the parameters are... 相似文献
63.
Allan H. Fawcett Avril E. Surgenor
Zahir Bashir
Robert E. Litchfield Norman G. Todd 《Polymer》1992,33(24):5282-5293Copolymers of acrylonitrile with a furfuryl alcohol resin have been prepared by a free radical reaction, and have been characterized by n.m.r. and i.r. spectroscopy. Their t.g.a. has been performed in air and in a nitrogen atmosphere, to permit the recognition of a number of stages in the weight loss process. D.s.c., also in air and in nitrogen, has identified a number of exothermic and one endothermic process in the copolymers. Solid state cross-polarization/magic angle spinning 13C n.m.r. spectroscopy and i.r. spectroscopy has been used to obtain some insight into the chemistry of the various chemical changes, which in air are completed by combustion and in nitrogen leave a carbon. 相似文献
64.
Alaeddin Bashir Abukabda Carroll Rolland McBride Thomas Paul Batchelor William Travis Goldsmith Elizabeth Compton Bowdridge Krista Lee Garner Sherri Friend Timothy Robert Nurkiewicz 《Particle and fibre toxicology》2018,15(1):43
Background
The cardiovascular effects of pulmonary exposure to engineered nanomaterials (ENM) are poorly understood, and the reproductive consequences are even less understood. Inflammation remains the most frequently explored mechanism of ENM toxicity. However, the key mediators and steps between lung exposure and uterine health remain to be fully defined. The purpose of this study was to determine the uterine inflammatory and vascular effects of pulmonary exposure to titanium dioxide nanoparticles (nano-TiO2). We hypothesized that pulmonary nano-TiO2 exposure initiates a Th2 inflammatory response mediated by Group II innate lymphoid cells (ILC2), which may be associated with an impairment in uterine microvascular reactivity.Methods
Female, virgin, Sprague-Dawley rats (8–12 weeks) were exposed to 100 μg of nano-TiO2 via intratracheal instillation 24 h prior to microvascular assessments. Serial blood samples were obtained at 0, 1, 2 and 4 h post-exposure for multiplex cytokine analysis. ILC2 numbers in the lungs were determined. ILC2s were isolated and phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-?B) levels were measured. Pressure myography was used to assess vascular reactivity of isolated radial arterioles.Results
Pulmonary nano-TiO2 exposure was associated with an increase in IL-1ß, 4, 5 and 13 and TNF- α 4 h post-exposure, indicative of an innate Th2 inflammatory response. ILC2 numbers were significantly increased in lungs from exposed animals (1.66?±?0.19%) compared to controls (0.19?±?0.22%). Phosphorylation of the transactivation domain (Ser-468) of NF-κB in isolated ILC2 and IL-33 in lung epithelial cells were significantly increased (126.8?±?4.3% and 137?±?11% of controls respectively) by nano-TiO2 exposure. Lastly, radial endothelium-dependent arteriolar reactivity was significantly impaired (27?±?12%), while endothelium-independent dilation (7?±?14%) and α-adrenergic sensitivity (8?±?2%) were not altered compared to control levels. Treatment with an anti- IL-33 antibody (1 mg/kg) 30 min prior to nano-TiO2 exposure resulted in a significant improvement in endothelium-dependent dilation and a decreased level of IL-33 in both plasma and bronchoalveolar lavage fluid.Conclusions
These results provide evidence that the uterine microvascular dysfunction that follows pulmonary ENM exposure may be initiated via activation of lung-resident ILC2 and subsequent systemic Th2-dependent inflammation.65.
Ramkumar Jayaraman Gunasekaran Raja Ali Kashif Bashir Chauhdary Sajjad Hussain Ali Hassan Mohammed A. Alqarni 《Wireless Personal Communications》2018,101(3):1539-1557
An intricate network deployment for high demand users leads to simultaneous transmission in wireless mesh networks. Multiple radios are adapted to individual nodes for improving network performance and Quality of Service (QoS). However, whenever multiple radios are assigned to the same channel, co-located radio interference occurs, which poses a major drawback. This paper proposes a Radio aware Channel Assignment (Ra-CA) mechanism based on a direct graphical model for mitigation of interference in multi-radio multi-channel networks. Initially, the co-located radio interference is identified by classifying non-interfering links for simultaneous transmission in the network. Proposed channel assignment mechanism helps in allocating the minimal number of channels to the network that mitigate co-located radio interference. Performance analysis of the proposed Ra-CA strategy is carried out compared with other existing techniques, like Breadth First Search-Channel Assignment (BFS-CA) and Maximal Independent Set Channel Assignment (MaIS-CA), in multi-radio networks. Simulation results demonstrate that the proposed channel assignment scheme is more efficient compared to the existing ones, in terms of QoS parameters like, packet drop rate, packet delivery ratio, transmission delay and throughput. 相似文献
66.
The design of a motion control system for a powered reciprocating gait orthosis is considered. Models for the orthosis are obtained using least squares identification. The control system design is based on pole-placement techniques and a restricted Youla parametrization of the controller. Experimental results are included. 相似文献
67.
M. M. Quazi M. Ishak A. Arslan M. Nasir Bashir Imran Ali 《Journal of Adhesion Science and Technology》2018,32(6):625-641
This study highlights the scratch adhesion failure characterization and tribo-mechanical properties of physical vapor deposited (Cr, Ti) N coating on AA7075-T6 by using magnetron-sputtering technique. The surface morphology, microstructure and chemical composition of CrTi/CrTiN film were inspected by an optical microscope, scanning electron microscope (SEM) incorporated with energy dispersive X-ray spectroscopy (EDX) in addition to focused ion beam milling. The coating to substrate critical load of about 1261 mN was obtained, by employing coating deposition parameters of; DC power (300 W, RF power (200 W)), temperature (300 °C) and nitrogen flow rate (6%). Failure adhesion characteristics exhibited initial arc-tensile cracking followed by chipping and spallation that led to complete coating failure at Lc3. The tribo-mechanical aspects were evaluated by a pin-on-plate reciprocating testing unit, which showed a lower friction coefficient of 0.36 for CrTiN as compared with 0.43 for AA7075-T6. Subsequently, the wear depth was also reduced from 9.5 to 5.9 μm. It was revealed that the wear mechanism for AA7075-T6 was extensive deformation, abrasion and delamination, while the CrTiN exhibited slightly oxidative abrasive wear mode. 相似文献
68.
DA Bushinsky MA Bashir DR Riordon Y Nakagawa FL Coe MD Grynpas 《Canadian Metallurgical Quarterly》1999,55(2):602-612
BACKGROUND: Human calcium oxalate (CaOx) nephrolithiasis may occur if urine is supersaturated with respect to the solid-phase CaOx. In these patients, dietary oxalate is often restricted to reduce its absorption and subsequent excretion in an effort to lower supersaturation and to decrease stone formation. However, dietary oxalate also binds intestinal calcium which lowers calcium absorption and excretion. The effect of increasing dietary oxalate on urinary CaOx supersaturation is difficult to predict. METHODS: To determine the effect of dietary oxalate intake on urinary supersaturation with respect to CaOx and brushite (CaHPO4), we fed 36th and 37th generation genetic hypercalciuric rats a normal Ca diet (1.2% Ca) alone or with sodium oxalate added at 0.5%, 1.0%, or 2.0% for a total of 18 weeks. We measured urinary ion excretion and calculated supersaturation with respect to the CaOx and CaHPO4 solid phases and determined the type of stones formed. RESULTS: Increasing dietary oxalate from 0% to 2.0% significantly increased urinary oxalate and decreased urinary calcium excretion, the latter presumably due to increased dietary oxalate-binding intestinal calcium. Increasing dietary oxalate from 0% to 2.0% decreased CaOx supersaturation due to the decrease in urinary calcium offsetting the increase in urinary oxalate and the decreased CaHPO4 supersaturation. Each rat in each group formed stones. Scanning electron microscopy revealed discrete stones and not nephrocalcinosis. X-ray and electron diffraction and x-ray microanalysis revealed that the stones were composed of calcium and phosphate; there were no CaOx stones. CONCLUSION: Thus, increasing dietary oxalate led to a decrease in CaOx and CaHPO4 supersaturation and did not alter the universal stone formation found in these rats, nor the type of stones formed. These results suggest the necessity for human studies aimed at determining the role, if any, of limiting oxalate intake to prevent recurrence of CaOx nephrolithiasis. 相似文献
69.
Bashir Jarrar Amin AlDoaiss Ali Shati Mohammed AlKahtani Qais Jarrar 《IET nanobiotechnology / IET》2021,15(2):221
Silicon dioxide nanoparticles (SiO2 NPs) are widely invested in medicine, industry, agriculture, consuming products, optical imaging agents, cosmetics, and drug delivery. However, the toxicity of these NPs on human health and the ecosystem have not been extensively studied and little information is available about their behavioural toxicities. The current study aimed to find out the behavioural alterations that might be induced by chronic exposure to 10 nm SiO2 NPs. BALB/C mice were subjected to 36 injections of SiO2 NPs (2 mg/kg Bw) and subjected to 11 neurobehavioural tests: elevated plus‐maze test, elevated zero‐maze test, multiradial maze test, open field test, hole‐board test, light‐dark box test, forced swimming test, tail‐suspension test, Morris water‐maze test, Y‐maze test and multiple T‐maze test. Treated mice demonstrated anxiety‐like effect, depression tendency, behavioural despair stress, exploration and locomotors activity reduction with error induction in both reference and working memories. The findings may suggest that silica NPs are anxiogenic and could aggravate depression affecting memory, learning, overall activity and exploratory behaviour. Moreover, the findings may indicate that these nanomaterials (NMs) may induce potential oxidative stress in the body leading to neurobehavioural alterations with possible changes in the vital organ including the central nervous system. 相似文献
70.
Adil Gani Shama Nazia Sajad A. Rather S.M. Wani Asima Shah Mudasir Bashir F.A. Masoodi Asir Gani 《LWT》2014
In this study red and white potato starches were treated with γ-irradiation of 0, 5, 10 and 20 kGy. Physicochemical, pasting and morphological properties of the irradiated starches were investigated. Apparent amylose content, pH, moisture, swelling power and syneresis decreased; whereas carboxyl content, water absorption capacity and solubility increased with increasing irradiation dose. Pasting properties also decreased significantly (p ≤ 0.05) upon increasing the irradiation dose. Observation under scanning electron microscope (SEM) showed surface cracking of the starch granules by γ-irradiation which increased with increase in irradiation dose. X-ray diffraction pattern remained the same upon irradiation but a decrease in relative crystallinity was observed with increasing irradiation dose. 相似文献