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51.
In this study, iron impregnated activated carbon (FeAC) was synthesized following an oxidation and iron impregnation of activated carbon (AC). Both the AC and FeAC were characterized by pHZPC and FTIR spectroscopy. The removal of Methylene Blue (MB) by AC and FeAC was examined under various experimental conditions. The FeAC showed up to 95% (higher than AC) MB removal in the pH range of 7–10. Although the reaction kinetics was pseudo–second order, the overall rate was controlled by a number of processes such as film diffusion, pore diffusion and intraparticle diffusion. The activation energy values for the MB uptake by AC and FeAC (21.79 and 14.82 kJ/mol, respectively) revealed a physisorption process. In the regeneration study, FeAC has shown consistently ≥ 90% MB removal even up to 10 repeated cycles. The reusable characteristic of the spent FeAC improved the practical use of activated carbon and can be a breakthrough for continuous flow system applications where it can work effectively without any significant reduction in its performance. 相似文献
52.
Word Sense Disambiguation (WSD) is the task of determining which sense of an ambiguous word (word with multiple meanings) is chosen in a particular use of that word, by considering its context. A sentence is considered ambiguous if it contains ambiguous word(s). Practically, any sentence that has been classified as ambiguous usually has multiple interpretations, but just one of them presents the correct interpretation. We propose an unsupervised method that exploits knowledge based approaches for word sense disambiguation using Harmony Search Algorithm (HSA) based on a Stanford dependencies generator (HSDG). The role of the dependency generator is to parse sentences to obtain their dependency relations. Whereas, the goal of using the HSA is to maximize the overall semantic similarity of the set of parsed words. HSA invokes a combination of semantic similarity and relatedness measurements, i.e., Jiang and Conrath (jcn) and an adapted Lesk algorithm, to perform the HSA fitness function. Our proposed method was experimented on benchmark datasets, which yielded results comparable to the state-of-the-art WSD methods. In order to evaluate the effectiveness of the dependency generator, we perform the same methodology without the parser, but with a window of words. The empirical results demonstrate that the proposed method is able to produce effective solutions for most instances of the datasets used. 相似文献
53.
Adnan Massadeh Ahmed Gharibeh Khaled Omari Idrees Al-Momani Ahmed Alomari Hiatham Tumah Wail Hayajneh 《Biological trace element research》2010,133(1):1-11
A total of 73 blood samples (56 from smokers and 17 from nonsmokers) were collected to determine the concentrations of selected
heavy metal in the whole blood of smokers and nonsmokers living in and around the city of Amman, Jordan. Analysis of heavy
metals in the whole blood samples of various groups took in consideration the number of cigarettes smoked per day. The analysis
of blood samples was carried out using inductively coupled plasma optical emission spectrometry. This study aimed to evaluate
the blood metal levels in smokers and nonsmokers and to assess the influence of smoking cigarettes on blood metal levels.
The results were compared with those from a control group. The results indicated that the average concentrations of cadmium
(Cd), lead (Pb), copper (Cu), zinc (Zn), and selenium (Se) were 0.0313, 0.344, 2.328, 3.214, and 0.332 mg/L, respectively.
Statistical analysis of results indicated that these average concentrations were significantly higher compared with the average
concentrations in nonsmokers (P < 0.05). Moreover, the correlations between blood metal and other blood metal levels in smokers, the correlations between
blood metal and other blood metal levels in nonsmokers, and the correlations between blood metal concentration in smokers
and its concentration in nonsmokers were calculated. The standard reference material (blood serum National Institute of Standards
and Technology 1598) and the quality control were used to validate the reliability of the method used for the estimation of
heavy metals in blood samples. Results revealed that there was an agreement between the certified values and the measured
values. 相似文献
54.
55.
Adnan Ayhanci Sibel Günes Varol Sahinturk Sila Appak Ruhi Uyar Mustafa Cengiz Yilmaz Altuner Suzan Yaman 《Biological trace element research》2010,136(2):171-179
The anticancer drug cyclophosphamide (CP) has nephrotoxic effects besides its urotoxicity, which both in turn limit its clinical
utility. The nephrotoxicity of CP is less common compared to its urotoxicity, and not much importance has been given for the
study of mechanism of CP-induced nephrotoxicity so far. Overproduction of reactive oxygen species (ROS) during inflammation
is one of the reasons of the kidney injury. Selenoproteins play crucial roles in regulating ROS and redox status in nearly
all tissues; therefore, in this study, the nephrotoxicity of CP and the possible protective effects of seleno l-methionine (SLM) on rat kidneys were investigated. Forty-two Sprague–Dawley rats were equally divided into six groups of seven
rats each. The control group received saline, and other rats were injected with CP (100 mg/kg), SLM (0.5 or 1 mg/kg), or CP + SLM
intraperitoneally. Malondialdehyde (MDA) and glutathione (GSH) levels in kidney homogenates of rats were measured, and kidney
tissues were examined under the microscope. CP-treated rats showed a depletion of renal GSH levels (28% of control), while
CP + SLM-injected rats had GSH values close to the control group. MDA levels increased 36% of control following CP administration,
which were significantly decreased after SLM treatment. Furthermore, these biochemical results were supported by microscopical
observations. In conclusion, the present study not only points to the therapeutic potential of SLM in CP-induced kidney toxicity
but also indicates a significant role for ROS and their relation to kidney dysfunction. 相似文献
56.
Akin Yilmaz Sevda Menevse Yildirim Bayazit Recep Karamert Volkan Ergin Adnan Menevse 《Biochemical genetics》2010,48(3-4):248-256
Most nonsyndromic hearing losses are caused by mutations in the GJB2 gene, and studies have revealed that the forms and frequencies of these mutations are largely dependent on ethnic origin. In the present study, we aimed to characterize the mutation profiles of 151 patients with hearing loss in Turkey. The entire coding region of the GJB2 was directly sequenced in all patients. We found 35 (23.2%) individuals carrying GJB2 mutations. Seven different mutations were identified, five of which were previously known (35delG, delE120, R184P, M163V, L90P), the remaining two being novel variants (M34V, L205V). The most common mutation was 35delG followed by delE120. The 35delG mutation was homozygous in 22 cases (14.5%) and heterozygous in 4 cases (2.6%). Compound heterozygosity for 35delG was also observed. The delE120 mutation was found in three patients in homozygous form. A homozygous L90P and heterozygous mutations M163V and M34V were found in single cases. 相似文献
57.
Ten Gram-positive and gram-negative bacterial cultures were recovered from nine water, mud, and soil samples collected from
the Dead Sea shore at Suwaymah. All bacterial cultures were able to grow at 10% NaCl and at 45°C. They were able to grow in
nutrient media supplemented with 1250 ppm of Zn. Most of them, except cultures 2 and 8, were able to grow in nutrient medium
supplemented with 1000 ppm of Cu. After 2 wk of incubation of these 10 cultures at different concentrations (5, 25, 100, and
500 ppm), stock solutions of both Zn and Cu elements, the maximum absorption using atomic absorption spectrometry for Zn was
achieved by culture 7 at 11.2%, 1.0%, 38.4%, and 84.54%, respectively, from the previous stock solutions, whereas the maximum
absorption of the same concentration of Cu was achieved by culture 3 at 6.2%, 55.56%, 85.66%, and 90.82%, respectively, of
the different concentrations. After 3 wk of incubation, the estimated absorption for Zn was achieved by cultures 2, 9, and
10 at 19.2%, 16.68%, 42.92%, and 76.5%, 18.2%, 21.56%, 32.22%, and 77.43%, and 20.8%, 23.52%, 32.22%, and 82.84% of the previous
stocks. The maximum absorption of the same concentration of Cu was achieved by culture 3 at 32.6%, 49.88%, 90.44%, and 91.86%,
respectively. The accumulation of the absorbed metals was found to be maximum in the protoplast of all cultures. The accumulation
at the cell wall was maximum for cultures 2 and 6 for Zn and Cu, respectively, and between the cell wall and the plasma membrane,
it was maximum for cultures 2 and 8 for Zn and Cu, respectively. 相似文献
58.
A number of ophiostomatoid fungi were isolated from the spruce-infesting bark beetle, Ips perturbatus and its galleries collected from felled spruce trees and logs in northern BC and the Yukon Territory. Isolates were identified to species using morphological characteristics, nuclear ribosomal DNA and partial β-tubulin gene sequences. Thirteen morphological and phylogenetic species were identified among the isolates. Leptographium fruticetum, Leptographium abietinum, Ophiostoma bicolor, Ophiostoma manitobense, O. piceaperdum, and eight undescribed species of the genus Ophiostoma and the anamorph genera Leptographium, Hyalorhinocladiella, Ambrosiella and Graphium. A number of these species, i.e. L. fruticetum, Hyalorhinocladiella sp. 2, O. bicolor and O. manitobense, were isolated repeatedly from I. perturbatus, while others, i.e. Graphium sp. 1 and O. piceaperdum, seemed to be␣sporadic associates. Among all the isolates, L. fruticetum had the highest relative dominance in this survey. A high frequency of occurrence of this species with the beetle may indicate a specific relationship between the two partners. 相似文献
59.
60.