30 research outputs found
Assessment of the genotoxicity of quinolone and fluoroquinolones contaminated soil with the Vicia faba micronucleus test
The genotoxicity of quinolone and fluroquinolones was assessed using the micronucleus (MN) test on Viciafaba roots by direct contact exposure to a solid matrix. Plants were exposed to quinolones (nalidixic acid) and fluoroquinolones (ciprofloxacin and enrofloxacin) alone or mixed with artificially contaminatedsoils. Four different concentrations of each of these antibiotics were tested (0.01, 0.1, 1 and 10 mg/Kg) for nalidixic acid and (0.005, 0.05, 0.5 and 5 mg/Kg) for ciprofloxacin and enrofloxacin. These antibiotics were also used in mixture. Exposure of Vicia faba plants to each antibiotic at the highest two concentrations showed significant MN induction. The lowest two concentrations had no significant genotoxic effect. The mixture of the three compounds induced a significant MN induction whatever the mixture tested, from 0.02 to 20 mg/Kg. The results indicated that a similar genotoxic effect was obtained with the mixture at 0.2 mg/Kg in comparison with each molecule alone at 5–10 mg/Kg. Data revealed a clear synergism of these molecules on Vicia faba genotoxicity
The sensing characteristics of ZnO tetrapods synthesized by microwave evaporation
ZnO tetrapods have been grown by an environmental microwave evaporation approach in air atmosphere without any use of organic solvents or precursors. The synthesized powder was characterized using X-ray diffractometry (XRD) and Field emission Scanning Electron Microscopy (FE-SEM). The grown ZnO tetrapods exhibited a noteworthy microstructure and phase formation of crystalline and pure structure. ZnO tetrapods were deposited on Pt electrode to be employed as ZnO tetrapods structure-based sensors, then, they were investigated at room temperature in the relative humidity ranging from 0.0 to 96.0%. The sensors have shown a significant response towards relative humidity starting from 30%. Cross-sensitivity was investigated with respect to N2O (150 ppm in helium) and methane (1000 ppm in helium). The ZnO tetrapods-based sensors were insensitive towards the interfering gases, indicating a potential applicability for humidity sensing purposes
Synthesis and Characterization of Nano-Tungsten Oxide Precipitated onto Natural Inorganic Clay for Humidity-Sensing Applications
A wet chemical method was used to obtain tungsten oxide nanoparticles from tungsten tetrachloride and natural microfibrous inorganic clay (sepiolite) as a starting material. Precipitation of tungsten oxide species onto sepiolite under basic conditions and subsequent thermal treatment was investigated, prompted by the abundance of sepiolite in nature and the useful environmental applications that could be attained. Laser granulometry, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and high-resolution transmission electron microscopy (HR-TEM) techniques were used to study the particle-size distribution, the morphology, and the composition of the prepared sample. Our findings show the presence of tungsten oxide nanoparticles, which are less than 50 nm, on the needles of the modified sepiolite
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Computer-based tools for assessing micro-longitudinal patterns of cognitive function in older adults
Patterns of cognitive change over micro-longitudinal timescales (i.e., ranging from hours to days) are associated with a wide range of age-related health and functional outcomes. However, practical issues with conducting high-frequency assessments make investigations of micro-longitudinal cognition costly and burdensome to run. One way of addressing this is to develop cognitive assessments that can be performed by older adults, in their own homes, without a researcher being present. Here, we address the question of whether reliable and valid cognitive data can be collected over micro-longitudinal timescales using unsupervised cognitive tests.In study 1, 48 older adults completed two touchscreen cognitive tests, on three occasions, in controlled conditions, alongside a battery of standard tests of cognitive functions. In study 2, 40 older adults completed the same two computerized tasks on multiple occasions, over three separate week-long periods, in their own homes, without a researcher present. Here, the tasks were incorporated into a wider touchscreen system (Novel Assessment of Nutrition and Ageing (NANA)) developed to assess multiple domains of health and behavior. Standard tests of cognitive function were also administered prior to participants using the NANA system.Performance on the two “NANA” cognitive tasks showed convergent validity with, and similar levels of reliability to, the standard cognitive battery in both studies. Completion and accuracy rates were also very high. These results show that reliable and valid cognitive data can be collected from older adults using unsupervised computerized tests, thus affording new opportunities for the investigation of cognitive function
Validated and optimized RP-HPLC method for the simultaneous quantification of meloxicam and its major metabolites in biological fluids with liquid liquid and solid phase extraction technique
Meloxicam is the most commonly prescribed non-steroidal anti-inflammatory drug. In this study, a simple, rapid and cost-effective method for the analysis of meloxicam and its major metabolites (5-hydroxy meloxicam and 5-carboxy meloxicam) in biological fluids (human plasma, urine and saliva) was developed and validated using RP-HPLC coupled with UV detector. The samples were analyzed by injecting 20 μl into the HPLC system using supelco analytical C18 (150 mm ×4.6 mm, 5 μm) column, protected by a C18 (30 mm×4.6 mm, 10 μm) Perkin Elmer, guard column. The mobile phase methanol: TFA (0.05% aqueous solution) in 60:40%v/v was pumped with a flow rate of 1.3 mL/min at ambient temperature and the eluents were checked at 353nm using Piroxicam as internal standard. Meloxicam and the metabolites were extracted from biological fluids using dichloromethane and the percent recovery for meloxicam, 5-hydroxy meloxicam and 5- carboxy meloxicam were 98.8%, 97.3%, 97% in plasma, 99%, 98.6%, 95.1% in urine and 95.8%, 92.9%, 92.7% in saliva, respectively. The limits of detection of meloxicam, 5-hydroxy meloxicam and 5-carboxy meloxicam were 3 ng, 10 ng and 8 ng, whereas limit of quantification were 9 ng, 30 ng and 25 ng, respectively. The method was linear over the concentration range of 10 - 2000 ng/mL for meloxicam, 30 - 1000 ng/mL, 25 - 1000 ng/mL for 5-hydroxy meloxicam and 5-carboxy meloxicam, respectively. The developed method was validated according to standard guidelines, various experimental parameters and chromatographic conditions such as mobile phase composition, flow rate, linearity, accuracy, precision, sensitivity etc. were optimized and were successfully applied for the pharmacokinetic studies in the plasma samples of the healthy human volunteers
Resonant final-state interactions in D^0 -> \bar{K}^{0} {\eta}, \bar{K}^{0} \eta' Decay
We have investimated the effect of the isospin 1/2, J^P = 0^+ resonant state
K^*_0(1950) on the decays D^0 ->\bar{K}^{0}\eta and D^0 ->\bar{K}^0 \eta' as a
function of the branching ratio sum r =Br(K^*_0(1950)->\bar{K}^0\eta)+
Br(K^*_0(1950)->\bar{K}^0 \eta' and coupling constants g_{K^*_0\bar{K}^0\eta},
g_{K^*_0\bar{K}^0\eta'}. We have used a factorized input for D^0 -> K^*_0(1950)
weak transition through a \pi K loop. We estimated both on- and off-shell
contributions from the loop. Our calculation shows that the off-shell effects
are significant. For a fit to the decay amplitude A(D^0 ->
\bar{K}^0 \eta') was possible, but the amplitude A(D^0 ->\bar{K}^0 \eta)
remained at its factorized value. For small values of r, , we were
able to fit A(D^0 -> \bar{K}^0 \eta), and despite the fact that A(D^0 ->
\bar{K}^0 \eta') could be raised by almost 100 % over its factorized value, it
still falls short of its experimental value. A simultaneous fit to both
amplitudes A(D^0 -> \bar{K}^0 \eta') and A(D^0 -> \bar{K}^0 \eta) was not
possible. We have also determined the strong phase of the resonant amplitudes
for both decays.
PACS numbers:13.25.Ft, 13.25.-k, 14.40.LbComment: 16 pages, 6 figures, 3 table
Inter-observer variability in fetal biometric measurements
Objective: To evaluate inter-observer variability and reproducibility of ultrasound measurements for fetal biometric parameters.
Materials and methods: A prospective cohort study was implemented in two tertiary care hospitals in Amman, Jordan; Prince Hamza Hospital and Albashir Hospital. 192 women with a singleton pregnancy at a gestational age of 18–36 weeks were the participants in the study. Transabdominal scans for fetal biometric parameter measurement were performed on study participants from the period of November 2014 to March 2015. Women who agreed to participate in the study were administered two ultrasound scans for head circumference, abdominal circumference and femur length. The correlation coefficient was calculated. Bland–Altman plots were used to analyze the degree of measurement agreement between observers. Limits of agreement ± 2 SD for the differences in fetal biometry measurements in proportions of the mean of the measurements were derived. Main outcome measures examine the reproducibility of fetal biometric measurements by different observers.
Results: High inter-observer inter-class correlation coefficient (ICC) was found for femur length (0.990) and abdominal circumference (0.996) where Bland–Altman plots showed high degrees of agreement. The highest degrees of agreement were noted in the measurement of abdominal circumference followed by head circumference. The lowest degree of agreement was found for femur length measurement. We used a paired-sample t-test and found that the mean difference between duplicate measurements was not significant (P > 0.05).
Conclusion: Biometric fetal parameter measurements may be reproducible by different operators in the clinical setting with similar results. Fetal head circumference, abdominal circumference and femur length were highly reproducible. Large organized studies are needed to ensure accurate fetal measurements due to the important clinical implications of inaccurate measurements
Fate of antibiotics present in a primary sludge of WWTP during their co-composting with palm wastes
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