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Zenker's diverticulum is a pharyngoesophageal outpouching of mucosa and submucosa through Killian's dehiscence.
Objective
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.
Methods
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.
Results
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.
Conclusion
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.
Method
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.
Results
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.
Conclusion
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.
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 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.
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.
While investigating Red Ring Disease of coconuts, the authors detected Rhadinaphelenchus cocophilus (Cobb, 1919) Goodey, 1960 in the root systems of three otherwise healthy coconut trees. One of these was about seven years old; the roots and the stem were sampled five times weekly but no stem or petiole infection was detected. A similar state of affairs was detected in the second tree. In neither case over a period of several weeks was there evidence of upward movement of the worm into the stem. The third tree was more interesting: the first sampling disclosed the presence of the nematodes in only one sample of roots out of four taken equidistantly around the stem; subsequent examination showed that the infection spread through the root system in the neighbourhood of the base of the tree until at the end of one month, worms were recovered from all parts of the proximal root system and the population had increased to 100–150 worms per gm. of root: many of these were sexually mature; after a further two weeks, there was still no upward movement into the stem.
In another publication (Fenwick, 19G3) data are presented on the distribution of infection in coconut trees infected with the nematode Rhadinaphelenchus cocophilus (Cobb, 1919) Goodey, I960. The data favour the hypothesis that the disease can start either in the root system and proceed by upward extension to the stem and thence to the petioles, or alternatively in the upper parts of the tree and proceed by downward extension through the stem to the roots, but this conclusion is arrived at by inference from the condition of trees at one given time. There is no information available on the condition of the trees at any previous time nor on what would have been their condition if allowed to stand. The writers therefore decided to make observations on a number of infected trees at weekly intervals in order to learn more about the course of the disease. To this end, trees were selected in which it was considered that the disease was in an early stage and observe its spread to other parts of the tree.
The leaching behaviour of a highly saline-sodic, moderately permeable, sandy-loam soil was evaluated under continuous and intermittent submergence conditions in a longterm field study in the presence of rice and subsequent wheat and sesbania crops. Leaching curves with respect to both desalinization and desodification showed that leaching efficiency was considerably higher with intermittent than with continuous submergence. The curves were useful in determining the amount of leaching water needed for a given mode of water application to reduce harmful levels of salinity and sodicity to acceptable ones. Empirical equations were determined to fit the experimental data. Their comparison with another empirical equation from published bare-field data of this site showed that leaching efficiency under crops was higher than under fallow. From the desodification leaching curve, it is concluded that in reclamation of these soils there is no need of the application of any amendment like gypsum. The soil salinity and sodicity data recorded at different growth stages and crop yields showed that leaching during the rice growing season, under intermittent submergence without previous leaching, decreased salinity and sodicity throughout the top 100 cm of the soil to levels safe for the successful cultivation of rice and subsequently the relatively deep-rooted crops of wheat and sesbania.
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.
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.
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.
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.
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.
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 aNiion replaces theBisite. 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.
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.
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.