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Zenker's diverticulum is a pharyngoesophageal outpouching of mucosa and submucosa through Killian's dehiscence.
To investigate the propensity for Zenker's diverticulum to occur on the left side by examining muscle thickness in Killian's dehiscence, and to explore correlations between muscle thickness, sex, height and age.
The study included 109 Caucasian cadavers, 52 male and 57 female. The mean thickest and thinnest measurements of left medial, left lateral, right medial and right lateral aspects of Killian's dehiscence were calculated. The paired student's t-test was used to determine significance.
The average left muscle layer was significantly thinner than the right muscle layer, in both medial and lateral aspects. Furthermore, medial muscle thickness was significantly thinner than its respective lateral aspect for both the left and right sides. No correlations were found between muscle thickness and cadavers’ sex, length or stature, or age.
There was a significant difference in muscle thickness between the left and right sides of Killian's dehiscence. The findings suggest there is a reason why Zenker's diverticulum occurs predominantly on the left side. The study also showed a significant difference in muscle thickness between the medial and lateral aspects of Killian's triangle.
Grewia tenax locally known as ‘Gangerun’, is an important multipurpose underutilized shrub and potentially threaten species of the Thar Desert of India. Owing to its importance, naturally available germplasm was collected and evaluated for its sustainable utilization in future. Data on individual mother plant, seed characters and soil profile were investigated. Habitat occurrence of G. tenax was found in patches with dominant association of Euphorbia caducifolia across the four districts of western Rajasthan. Individual plant on unprotected area portrayed far lower average height (0.95 m) and canopy area (1.75 m2) than protected area (2.63 m and 13.89 m2) signifying level of browsing pressure on this species in Jaisalmer. Soil samples belonging to Pali region have high organic carbon and low electrical conductivity content than Jaisalmer and Jodhpur. The statistical analysis of seed characters revealed the presence of high coefficient of variation (%) in 100-seed weight (HSW; 27.36) followed by seed length (SL; 8.06) and least in seed breadth (SB; 5.85). The range and mean values of HSW, SL, SB and length:breadth ratio (LBR) were (2.02–7.00 and 3.34 g), (4.36–6.15 and 5.36 mm), (3.73–4.68 and 4.25 mm) and (1.11–1.44 and 1.27), respectively. Significantly positive correlation was observed between SL and LBR (0.73) followed by HSW and SL (0.66). Along with these findings, its economic importance, utilization and conservation are detailed in this paper as to hasten further research on its various aspects for its successful conservation and utilization.
To compare combined conventional Freer medialisation and controlled synechiae, performed for middle meatal access (during the initial steps of functional endoscopic sinus surgery) and post-operative middle turbinate medialisation, with basal lamella relaxing incision, the latter of which is a single step for achieving both middle meatal access and post-operative medialisation. The study also compared the effects of controlled synechiae and basal lamella relaxing incision on post-operative olfaction.
A randomised prospective study was performed on 52 nasal cavity sides (32 patients). Only basal lamella relaxing incision was performed in one group, and both conventional medialisation and controlled synechiae were performed in the other. Intra-operative and post-operative photography was used to measure the middle meatal area. A pocket smell test was used to assess olfaction.
There were no significant differences in operative middle meatal access and post-operative medialisation of the middle turbinate. Post-operative olfaction was affected more in the combined conventional medialisation and controlled synechiae group, compared to the basal lamella relaxing incision group, but this finding was not statistically significant.
Basal lamella relaxing incision is an effective single-step technique for achieving adequate middle meatal access and post-operative medialisation, with no significant effect on olfaction.
Using a fluid theory approach, this article provides a comparative study on the evolution of nonlinear waves in dusty plasmas, as well as other plasma environments, viz electron-ion, and electron-positron plasmas. Where applicable, relevance to satellite measurements is pointed out. A range of nonlinear waves from low frequency (ion acoustic and ion cyclotron waves), high frequency (electron acoustic and electron cyclotron waves) in electron-ion plasmas, ultra-low frequency (dust acoustic and dust cyclotron waves) in dusty plasmas and in electron-positron plasmas are discussed. Depending upon the plasma parameters, saw-tooth and bipolar structures are shown to evolve.
Metal oxide nanostructures have shown significant promise for biosensors, gas sensors, photocatalyst and other biomedical applications. Among these, zinc oxide (ZnO) nanostructures, exhibiting interesting properties such as high catalytic activity, biocompatibility, high isoelectric point, large surface to volume ratio, make them a good candidate for biosensing applications. Here we report the synthesis of ZnO nanorods (ZnONR) on ITO films in aqueous phase and its application in Urea biosensor fabrication. ZnONR have been synthesized by a two-step method, first seed growth of ZnO by sputtering on ITO films followed by decomposition of zinc nitrate hexahydrate / hexamethylenetetramine (HMT) in aqueous phase. Exploiting the high isoelectric point of ZnO, a Urease/ZnONR/ITO bioelectrode has been fabricated by physical binding of Urease (Urs) onto ZnONRs. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and cyclic voltammetry (CV) have been used to characterize ZnONR and the Urs/ZnONR/ITO bioelectrode. The FE-SEM and XRD measurements confirm the formation of ZnONR. The electrochemical data from the Urs/ZnONR/ITO biolectrode reveal linearity between 1-11 mM with sensitivity of 0.9 μA/mM and a relatively low Michaelis-Menten constant (Km) of 5.01 mM for urea sensing. The results indicate the potential of ZnONR films for fabrication of commercial biosensors.
Nickel-substituted Bi4Ti3O12 (i.e., Bi4-xNixTi3O12) were synthesized by sol-gel process for different compositions. Thin films were deposited on Pt (i.e., Pt/TiO2/SiO2/Si) substrate by spin coating. Materials were characterized by x-ray diffraction and Raman spectroscopy. This study indicates that the material makes a solid solution for the compositions: x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.30, where a Ni ion replaces the Bi site. The prominent effect of Ni substitution was observed in low-frequency Raman modes. Sol-gel derived thin films of Bi4-xNixTi3O12 on a Pt substrate and post annealed at 700°C were tested for ferroelectric response which showed high remnant polarization (Pr = 22 μC/cm2 for x = 0.15). The leakage current (less then 10−7 A/cm2) at low field was observed in the film with composition x = 0.15 .The polarization of the BNiT (x = 0.15) film decreased to 83% of the initial value after 1×109 switching cycles These results indicate the potential application of Ni substituted bismuth titanate films in non-volatile ferroelectric memories.
LiMn1.5Ni0.5O4 cathode material was prepared by sol-gel method and annealed at 850°C for 15 hrs. The prepared powder was coated with ZnO by dissolving zinc acetate in methanol and LiMn1.5Ni0.5O4 powder was mixed in this solution followed by the continuous stirring for 4 hr. The LiMn1.5Ni0.5O4 and ZnO coated LiMn1.5Ni0.5O4 powder was characterized using X-ray diffraction, TEM and Raman spectroscopy. The coin cell was fabricated using LiMn1.5Ni0.5O4 and ZnO coated LiMn1.5Ni0.5O4 as cathode materials, LiPF6, dissolved in EC/DMC (1:1 wt ratio) as electrolyte, and Li foil as anode. The cyclic voltammetric and charge-discharge characteristics were carried out for the coin cell using LiMn1.5Ni0.5O4 and ZnO coated LiMn1.5Ni0.5O4 cathode materials. It was found that the ZnO coated LiMn1.5Ni0.5O4 cathode materials showed improved discharge capacity (∼146mAh/g) as compared to the pure LiMn1.5Ni0.5O4 (∼140mAh/g). The discharge capacity retention after 50 cycles was found to be about 94% and 97% for LiMn1.5Ni0.5O4 and ZnO coated LiMn1.5Ni0.5O4 cathode materials, respectively.
We have synthesized spinel LiMn1.99Nd0.01O4 and LiMn1.99Ce0.01O4 powder by chemical synthesis method. The synthesized powders were used to prepare cathodes for Li ion coin cells. The structural and electrochemical properties were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry and charge-discharge studies, respectively. The cyclic voltammetry of the cathodes revealed the reversible nature of Li-ion intercalation in the cell. The charge-discharge characteristics for LiMn1.99Ce0.01O4 were obtained in 3.5 V – 4.8 V voltage range, while for LiMn1.99Nd0.01O4 the charge-discharge were carried out in 3.4 V – 4.4 V range. The initial discharge capacities of LiMn1.99Ce0.01O4 and LiMn1.99Nd0.01O4 were obtained as 134mAh/g and 149 mAh/g, respectively. The coin cells were tested for up to 25 charge-discharge cycles and after 25 cycles the discharge capacities were determined to 79.5 mAh/g and 132 mAh/g for LiMn1.99Ce0.01O4 and LiMn1.99Nd0.01O4 cathodes respectively. However, by doping with a small concentration of rare earth materials, like Ce and Nd reduces the capacity fading in pure LiMn2O4 cathodes making it suitable for Li-ion battery applications.
Gadolinium-substituted Bi4Ti3O12 (i.e. Bi4−xGdxTi3O12) were synthesized by sol-gel process for different compositions, and thin films were deposited on Pt (Pt/TiO2/SiO2/Si) substrate by spin coating. Post annealed films at 700° C were investigated for their structural properties using x-ray diffraction and Raman spectroscopy indicating solid solution for compositions: x = 0.00, 0.46, 0.56, and 0.85 where Bi ion is replaced by Gd-ion. Sol-gel derived Pt/Bi4−xGdxTi3O12 film/Pt capacitor structure was tested for dielectric, ferroelectric, and leakage current responses. Films showed ferroelectricity with polarization, Pr = 22 µC/cm2 for composition: x = 0.46. Magnetic response of the powder sample for composition: x = 0.85 was tested using SQUID, which showed superparamagnetic at room temperature and magnetic at 5 K with magnetic coercivity (Hc) = 29 Oe and very small remanance (σr) = 5.4 × 10−4 emu/g.
Materials which possess electrical and magnetic coupling are of great interest for novel devices. Bi(Fe1-xCox)O3 (BFCO) material system was synthesized by solution route for various compositions and thin films were prepared by spin coating on Pt (Pt/Ti/SiO2/Si) substrates. Structural properties of the films were investigated by x-ray diffraction and Raman spectroscopy. X-ray diffraction patterns confirms intense (110) in BiFeO3 and Bi(Fe1-xCox)O3 with rhombohedra distorted perovskite structure without impure phase. Bi(Fe1-xCox)O3 films show week ferroelectric polarization and ferromagnetism at room temperature. Ferroelectric and ferromagnetic coupling could be attributed to the elimination of oxygen vacancies and increased stress in the crystal structure by partial replacement of Fe2+ ion by Co2+ ion.
The use of nanoparticles as carriers of photosensitizer (PS) molecules for photodynamic therapy (PDT) has attracted much interest on core-shell nanosize structures. Herein, we used a simple aqueous solution method to synthesize Fe3O4/ZnO core-shell nanoparticles. X-ray diffraction (XRD) analyses showed the presence of well defined peaks corresponding to Fe3O4 and ZnO in as-synthesized nanocrystals. Vibrating sample magnetometer (VSM) measurements showed that these nanoparticles exhibited superparamagnetic behavior of the core with no coercivity nor remanence. X-ray photoelectron spectroscopy (XPS) analyses revealed the presence of Zn1/2 and Zn3/2 species on the surface of nanocrystals. Photoluminescence measurements showed excitonic emission of ZnO co-existing with a weak and broad defect- related green emission at room temperature. The generation of singlet oxygen was monitored via the photooxidation of diphenyl-1,3-isobenzofuran (DPBF) with different light sources, followed by absorption spectroscopy at 409 nm. The capability of synthesized nanoparticles to generate singlet oxygen has also been verified.
Zn0.90Co0.10O and Zn0.85[Co0.50Fe0.50]0.15O targets were used to grow thin films by rf magnetron sputtering. XRD patterns of the films showed a strong preferred orientation along c-axis. Zn0.90Co0.10O film showed a transmittance above 75% in the visible range, while the transmittance of the Zn0.85[Co0.50Fe0.50]0.15O film was about 45%; with three absorption peaks attributed to d-d transitions of tetrahedrally coordinated Co2+. The band gap values for Zn0.90Co0.10O and Zn0.85[Co0.50Fe0.50]0.15O films were 2.95 and 2.70 eV respectively, which are slightly less than ZnO bulk. The Zn0.90Co0.10O film showed a relatively large positive magnetoresistance (MR) at the high magnetic field in the temperature range from 7 to 50 K, which reached 11.9% a 7K for the magnetoresistance. The lowest MR was found at 100 K. From M-H curve measured at room temperature shown a probable antiferromagnetic behavior, although was possible to observe little coercive field of 30 Oe and 40 Oe for Zn0.90Co0.10O and Zn0.85[Co0.50Fe0.50]0.15O films, respectively.
Diluted magnetic semiconductors (DMS) have been explored extensively, because of their potential application in spintronic devices. We studied the structural optical and magnetic properties of Ti1-xMxO2 (M= Fe, Mn, Co; x = 0.00, 0.05, 0.08, 0.10, 0.15, 0.20, 0.25, 0.30), thin films by sol-gel process and deposited using spin coating on Pt (Pt/Ti/SiO2/Si) and quartz substrates. X-ray diffraction studies and Raman spectroscopy reveal anatase and rutile phases of the synthesized films when annealed at 500 and 10000 C, respectively. Optical transmission measurements show high degree of transparency that decreases with increase in transition metal ion concentration. The films show room temperature ferromagnetism, suggesting their potential in spin based heterojunction devices.
We synthesized BiFe1-xMnxO3 (BFMO) for various compositions by sol gel process and thin films were deposited by spin coating on platinum Pt/Ti/SiO2/Si substrates. X-ray diffraction shows all the diffraction planes corresponding to rhombohedrally distorted perovskite BiFeO3 structure. The absence of any impurity phase in the films suggests the incorporation Mn ion preferentially to Fe site in the structure for low concentration. Magnetic measurements reveal the formation of ferromagnetic phase at room temperature with increased Mn substitution. On the other hand, ferroelectric polarization decreases with increasing Mn ion concentration. Raman studies suggest the dopant induced structural distortion.
We report a systematic study of the influence of the target-substrate distance and rf power on the structural and optical properties of ZnO thin films grown by rf magnetron sputtering in Ar atmosphere from ZnO sputtering target. Sharp (002) peak showed by XRD indicates a c-axis crystalline growth of ZnO films. Growth rate remained almost constant for short target-substrate distances. However, the grain size increases with the rf power decreasing the compressive stress in ZnO films. As-grown ZnO films have average transmittance more than 80% in the visible region. Optical bandgap (Eg) increases from 3.18 to 3.27 eV as increase the target-substrate distance probably due to low stress compression in ZnO films. In addition, when rf power is above 100 W, the optical band gap increases as increase of the stress compression.
The existence of large amplitude solitary waves in a plasma comprised of a cold negative dust fluid, adiabatic positive dust fluid, Boltzmann electrons and non-thermal ions is theoretically investigated. Different regions in parameter space that correspond to different values of the ratio of the charge-to-mass ratios of the positive and negative dust grains have been identified where either negative or positive potential solitary wave structures occur and a region where coexistence of negative and positive potential solitary waves is supported.
The nonlinear propagation of the dust-acoustic wave is investigated in a weakly non-ideal plasma comprising Boltzmann electrons, non-thermal ions characterized by a non-thermal parameter α and a negatively charged dust fluid. The non-ideal dust fluid is represented by the van der Waals equation of state. Arbitrary amplitude soliton solutions are found to occur for both supersonic and subsonic values of the Mach number. Upper and lower limits of the range of values of α for which solitons exist are examined as a function of the non-ideal parameters associated with the effects of volume reduction and the cohesive forces, for both the supersonic and subsonic cases.
The existence of large-amplitude dust-acoustic double layers is investigated in an unmagnetized dusty plasma comprising a negatively charged warm dust fluid, non-thermal ions and Boltzmann electrons. It is found that the non-thermal plasma supports the existence of rarefactive double layers only. The dependence of the double-layer amplitude and Mach number on various parameters such as the non-thermal parameter, dust temperature and electron concentration is numerically examined.
The influence of non-thermal ions on linear dust-acoustic waves is studied in an unmagnetized plasma consisting of ions which have a non-thermal velocity distribution, Boltzmann-distributed electrons and streaming dust particles. A detailed examination is conducted of the dependence of the real frequency and growth rate of the excited instability on the dust drift speed, temperature, particle densities and the parameter $\alpha$ that determines the non-thermal nature of the energetic ions. Comparisons with approximate analytical solutions are also made.