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[en] A rhodamine B-based fluorescent probe for nitrite ion (NO2-) has been designed, synthesized, characterized and its properties for recognition of NO2- were studied. Nearly non fluorescent probe upon reaction with nitrite ion significantly triggered the fluorescence. Fluorescence response is based on ring opening of the spirolactam of rhodamine B phenyl hydrazide showing maximum absorbance at 552 nm and maximum emission at 584 nm. Probe 3 exhibited high sensitivity and extreme selectivity for nitrite ion over other common ions and oxidants (Cl-, ClO-, ClO2-, ClO3-, ClO4-, SO42-, SiO32-, NO32-, CO32-) examined in methanol water (1:1, v/v) at pH 7.0. The probe might be a new efficient tool for detection of nitrite ion in natural water and biological system
[en] With an aim to reveal the mechanism of water-protein interaction from the dielectric response of a model fibrous protein, the dielectric constant ε' and loss factor ε-prime have been measured in air dried and vacuum dried samples of bovine tendon collagen in the frequency range 30 Hz-3 MHz and temperature range 30-200 deg. C. An anomalous low frequency dispersion (LFD) and an intermediate frequency strong α-dispersion peak were the two main dielectric responses observed in the air dried sample. The LFD followed the fractional power law of frequency while the α-dispersion conformed to the Cole-Cole modified Debye equation. These dispersions, respectively, have been attributed to percolation of protons between and within the clusters of hydrogen bonded water molecules bound to polar or ionizable protein components. In the vacuum dried sample, however, a very weak high frequency α2-dispersion peak was observed, which was hidden below the strong α-dispersion in the air dried sample. This peak may be attributed to reorientation of polar components of the collagen molecule. Temperature dependence of the dielectric data shows release of bound water as a four-step process with discrete peaks at 50, 90, 125 and 160 0C. These peaks have been attributed to the onset of the release of adsorbed surface water, water bound to exposed polar sites, water bound to internal polar sites and very strongly bound structural water, respectively
[en] To report our experience of managing extensive retroperitoneal hematoma (RH) in patients with blunt trauma and to determine any associated factors affecting causation and mortality. In this retrospective observational study, patients diagnosed with extensive RH following blunt trauma admitted to King Saud Medical Complex, Riyadh, Kingdom of Saudi Arabia between January 2004 and December 2009 were included. Patient data were explored for injury severity score (ISS), associated injuries, location of hematoma, amount of blood transfusions, coagulation profile, operative management, hospital stay, and mortality. The outcomes in surviving and non-surviving patients were compared. Out of 290 patients presenting with RH, extensive RH was found in 46 patients (15.8%). The overall mortality was 32.6%. The pelvis was the most frequent location of RH in combination with lateral and central zones (65.2%). The lower extremity and pelvic fractures were the most common injury. Associated intra-peritoneal injuries were present in 39.1% patients. An exploratory laparotomy was performed in 58.7% patients (n=27). A high ISS (55.9 versus 35.5, p<0.0001), abnormal coagulation profile (odds ratio [OR] 7.8, 95% confidence interval [CI] 1.974-30.932, p=0.005, and associated chest injuries OR 5.94, 95% CI 1.528-23.19, p=0.014) were independent factors associated with mortality. Multiple musculoskeletal injuries in addition to intra-abdominal injuries and abnormal coagulation are major factors associated with the presence of extensive RH. High ISS, abnormal coagulation, and associated chest injuries are independent factors associated with mortality (Author).
[en] This study was conducted for microwave assisted synthesis of stable gold nanoparticles (AuNPs) by reduction of chloroauric acid with Elaeis Guineensis (palm oil) kernel (POK) extract which was prepared in aqueous solution of ionic liquid, [EMIM][OAc], 1-Ethyl-3-methylimidazolium acetate. Effect of initial pH of reaction mixture (3.5 - 8.5) was observed on SPR absorbance, maximum wavelength (λmax ) and size distribution of AuNPs. Change of pH of reaction mixture from acidic to basic region resulted in appearance of strong SPR absorption peaks and blue shifting of λmax from 533 nm to 522 nm. TEM analysis revealed the formation of predominantly spherical AuNPs with mean diameter of 8.51 nm. Presence of reducing moieties such as flavonoids, phenolic and carboxylic groups in POK extract was confirmed by FTIR analysis. Colloidal solution of AuNPs was remained stable at room temperature and insignificant difference in zeta value was recorded within experimental tenure of 4 months. (paper)
[en] The damage of UV radiation on human eye and skin is extensively studied. In the present work, the nanocomposites foils and thin films have been prepared by using casting method and spin coating, respectively. Nanocomposites were prepared by mixing ZnO nanoparticles with Polymethyl methacrylate (PMMA) and Polyvinylidene fluoride (PVDF) as polymer matrix. Different contents of ZnO nanoparticles were used as filler in the nanocomposites. UV-Vis spectra showed very low transmittance in UV region that decreases with increase content of ZnO. PVDF/ZnO samples showed the lowest transmittance. The rough surface of PVDF was observed from SEM image. While a homogeneous dispersion of ZnO nanoparticles in PMMA were indicated by FESEM images
[en] Dielectric constant ε' and loss factor ε'' have been measured in bovine tendon collagen in the frequency range 30 Hz - 3 MHz and temperature range 30 deg. C to 200 deg. C. Frequency dependence curve of ε'' shows a low frequency strong α-dispersion attributed to phonon assisted proton hopping between localized sites and a weak high frequency. α2 - dispersion attributed to reorientation of polar components of collagen molecules. Temperature dependence of the dielectric data show release of bound moisture as a three step process with discrete peaks at 50 deg. C, 90 deg. C and 125 deg. C. These peaks have been attributed to release of adsorbed surface water, water bound to exposed polar sites and strongly bound internal moisture respectively. A peak observed at 160 deg. C has been attributed to thermally induced helix-coil transition of collagen molecules. (author)
[en] To evaluate whether magnetic resonance imaging (MRI) can serve as an alternative diagnostic tool to the “gold standard” cone-beam computed tomography (CBCT) in 3D cephalometric analysis. In this prospective feasibility study, 12 patients (8 males, 4 females; mean age ± SD, 26.1 years ± 6.6) underwent 3D MRI and CBCT before orthognathic surgery. 3D cephalometric analysis was performed twice by two independent observers on both modalities. For each dataset, 27 cephalometric landmarks were defined from which 35 measurements (17 angles, 18 distances) were calculated. Statistical analyses included the calculation of Euclidean distances, intraclass correlation coefficients (ICCs), Bland-Altman analysis, and equivalence testing (linear mixed effects model) with a predefined equivalence margin of ± 1°/1 mm. Analysis of reliability for CBCT vs. MRI (intra-rater I/intra-rater II/inter-rater) revealed Euclidean distances of 0.86/0.86/0.98 mm vs. 0.93/0.99/1.10 mm for landmarks, ICCs of 0.990/0.980/0.986 vs. 0.982/0.978/0.980 for angles, and ICCs of 0.992/0.988/0.989 vs. 0.991/0.985/0.988 for distances. Bland-Altman analysis showed high levels of agreement between CBCT and MRI with bias values (95% levels of agreement) of 0.03° (− 1.49; 1.54) for angles and 0.02 mm (− 1.44; 1.47) for distances. In the linear mixed effects model, the mean values of CBCT and MRI measurements were equivalent. This feasibility study indicates that MRI enables reliable 3D cephalometric analysis with excellent agreement to corresponding measurements on CBCT. Thus, MRI could serve as a non-ionizing alternative to CBCT for treatment planning and monitoring in orthodontics as well as oral and maxillofacial surgery.
[en] Chemical characteristics of blends of palm oil and mango kernel oil for their probable use as vanaspati was studied. Crude mango kernel oil was blended with refined, bleached and deodorised palm oil from 10 %, 20 %, 30 %, 40 % and 50 % (T_1, T_2, T_3, T_4 and T_5) market vanaspati was used as control. Concentration of trans fatty acids in control was 22.7 %, whereas, all the vanaspati samples were virtually trans-free. Slip melting points (degree Celsius) of control, T_1, T_2, T_3, T_4 and T_5 were 37.5, 37.3, 36.4, 35.6, 34.8 and 34. Free fatty acids of control and T5 were respectively 0.11, 0.12 %. Polymer contents of control, T_1, T_2, T_3, T_4 and T_5 , after three heating cycles (18 degree Celsius, for 8 hr) were 21.55 %, 20.97 %, 18.66 %, 17.61 % and 10.22 %, respectively with lower solid fat index (p<0.05). Blends of mango kernel oil and palm oil can be used for the formulation of trans-free vanaspati. (author)