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Purpose To report a sutureless method of amniotic membrane fixation using fibrin glue in two cases of symptomatic bullous keratopathy with poor visual potential.Methods Under topical anesthesia, the loose epithelium was debrided up to 1.0 mm from the limbus and fibrin glue was applied uniformly and thinly onto the corneal surface. Cryopreserved amniotic membrane was evenly placed over the cornea and once a firm and uniform adhesion was achieved, excess membrane was trimmed off. A bandage contact lens was applied.Results In both the cases, complete relief from symptoms was obtained and 3 weeks later, the ocular surface had completely re-epithelialized. At 6 months follow-up, both patients were symptom free without the need for any medication. No complications were observed.Conclusions This technique of amniotic membrane fixation is a simple, effective, and safe procedure whereby a stable and secure adherence of the amniotic membrane with the corneal surface is achieved avoiding the use of sutures.

Molar excess volumes for the binary mixtures of cyclohexanone with benzene and some monosubstituted benzenes, namely, toluene, ethylbenzene, isopropylbenzene, tertiary butylbenzene, chlorobenzene, bromobenzene, iodobenzene, N,N-dimethylaniline, nitrobenzene, benzaldehyde, and benzonitrile have been calculated from the precise and accurate experimental density data at 298.15 K over the entire composition range. The results have been discussed in terms of the strength of molecular interactions in the binary mixtures.

Excess volumes of mixing, VE, for binary mixtures of eyelohexanone with n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, n-tetradecane, and n-hexadecane at 25 °C were determined from the precise and accurate experimental density data. The sign and magnitude of VEwere discussed in terms of the strength of the unlike interactions present in the binary mixtures.Excess volumes of mixing of equimolar concentration were also obtained. Attempts were made to interpret in terms of the size and polarity of the constituent molecule. The two effects could not be separated, but a good linear relation between and the solubility parameter was found.

Integral heats of solution ?Hs of sodium carboxylates, CnH2n+1COONa (n=0, 1, 2, 3, 4, 5, and 7) and C6H5(CH2)nCOONa (n=0, 1, 2, and 3), in water at 25 and 35°C have been determined at very low concentrations. The heat capacities of dissolution at infinite dilution, ‡Cpo, of sodium carboxylates have been derived by the integral heat method. The-CH2-increment of ‡Cpo in aliphatic carboxylates has been found to be 14 cal-deg-1-mole-1, which is close to the value derived from other series of compounds, indicating that the interaction of nonpolar moieties with water is independent of the hydrophilic group attached to it. On the other hand, the-CH2-increment for the aromatic sodium carboxylates is much less (about 6 cal-deg-1-mole-1) than for the aliphatic sodium carboxylates, indicating that the hydrophobic interaction is affected by the aromatic end group.

A very simple isopiestic method based on that of S. Christian is used for measuring the salting-in of water into nonpolar, low-volatility solvents by tetraalkylammonium salts. The quantity of excess water which is dissolved in such solvents is directly proportional to the salt concentration and is sharply dependent on the nature of the anion but is nearly insensitive to that of the R4N+ cation. The hydration ratioH, which we define as the moles of excess solubilized water per mole of R4N+ X-, is directly relatable to the enthalpy of hydration of the anion X- in several solvents and in the gas phase. The quantityH is also correlated with many free-energy terms including those for the Hofmeister lyotropic series, for the ability of the anions to salt nonelectrolytes out of water, for the free-energy terms for separation of these ions by reverse osmosis membranes, and for their nucleophilicities. A surprising (but not unprecedented) feature of the hydration ratio is that it, rather than its logarithm, behaves as a free-energy term. It is proposed that all these properties have in common the free energy of hydration of the anions, and this notion is supported by a close correspondence between the anionic hydration ratio and their hydrogen-bonding energies with proton donors in aprotic solvents. The results support scattered observations by other workers that isolated water molecules do not have an unusual inherent affinity for anions. Accordingly, large anionic hydration energies in bulk aqueous media reflect extensive cooperative interactions in the solvent. Implications for nucleophilic activity in phase transfer catalysis and enzyme activity are mentioned.

A high-performance liquid chromatography method was developed to determine the amount of each of the compound classes (such as saturates, aromatics and polars) in the oil fraction (pentane soluble fraction) of coal liquids. The method utilizes bonded cyanosilane and aminocyanosilane columns and mixtures of benzene in n-hexane and tetrahydrofuran in methyl tert-butyl ether as mobile phases. A Tracor LC-rotating disc flame ionization detector was used to quantify the chromatographic peaks.Oil fractions derived from different rank coals, liquefied at 385° and 445°C. were analyzed for their compound class compositions. The trends in the percentages of saturates, aromatics and polars varied with liquefaction temperature and coal rank.

Normal incidence of linearly polarized electromagnetic waves on a semi-infinite longitudinally drifting, homogeneous, temperate magnetoplasma, where the static magnetic field is in the longitudinal direction, is considered. The reflected and transmitted waves from the drifting boundary of the magnetoplasma are calculated and both relativistic and nonrelativistic solutions are presented. It has been found that both solutions give identical results for the present case. Si studia l’incidenza perpendicolare di onde elettromagnetiche polarizzate linearmente su un magnetoplasma temperato, omogeneo, semiinfinito, in moto longitudinale, nel quale il campo magnetico statico è in direzione longitudinale. Si calcolano le onde trasmesse e riflesse dal contorno del magnetoplasma in spostamento e si presentano le soluzioni sia relativistiche che non relativistiche. Si trova che entrambe le soluzioni danno nel caso presente risultati identici. Рассматривается нормальное падение линейно поляриэованных злектромагнитных волн на полубесконечную продольно дрейфуюшую, однородную магнитоплаэму, в которой статическое магнитное поле направлено в продольном направлении. Вычисляются отраженные и прощедщие волны от дрейфуюшей границы магнитоплаэмы, и представлены релятивистские и нерелятивистские рещения. Было обнаружено, что в данном случае оба рещения дают идентичные реэультаты.

Abstract:  Lycopersicon peruvianum displays gametophytic self-incompatibility (GSI). We have isolated self-compatible (SC) tetraploids of L. peruvianum from tissue-cultured leaves and have explored the expression and inheritance of their S-related proteins. The Srelated protein profiles of styles of SC tetraploids were indistinguishable from the diploid self-incompatible (SI) explant source based on SDS-PAGE. All progeny obtained from self-fertilization of two tetraploids were SC. Cloned cDNA sequences of the S-related proteins were used to determine the inheritance of this locus in these progeny through Southern hybridization. The allelic ratio, as determined from the intensity of DNA restriction fragments, was consistent with the predicted ratio if only pollen bearing two different alleles was successful in achieving fertilization. All progeny obtained had at least one copy of each allele, and individuals fully homozygous for either allele were not found, indicating that pollen grains bearing two identical alleles were inhibited. In addition, the level of expression of the S-related proteins in the progeny correlated with the allelic dosage at the DNA level. We demonstrate that the observed self-compatibility in the tetraploids was not caused by an alteration in the expression of S-related proteins.

Propyliodone oily injection B.P. exhibits thixotropy under high shear rates and rheopexy under low shear rates. The rate and the degree of rheopectic build-up of structure are influenced by the particle size, the effect increasing as the median particle size is reduced.

The viscosity of dispersions of ascorbic acid in solutions of polysorbate 20 has been determined and found to be Newtonian at all concentrations studied. The course of the oxidation in polysorbate 20 appeared to be by the normal chain reaction, but the rate at which it occurred was modified by a number of factors. Incorporation within the micelle appeared to be responsible for an increase in oxidation rate, but the high viscosity of concentrated polysorbate 20 solutions, which would affect the diffusion of oxygen to the reaction site caused a much larger reduction in oxidation rate.

Changes induced by temperature in the relative position and extent of the isotropic and liquid crystal phases present in the ascorbic acid-water-polysorbate 80 system have been recorded. Increases in temperature reduce the size of the liquid crystal phase. This phase is pseudoplastic, but a small central region also shows thixotropic hysteresis loops. On recycling, most systems show Newtonian behaviour. In the isotropic regions, an increase in temperature results in a fall in log of viscosity proportionate to 1/Tabs, but in the liquid crystal region an increase in temperature may cause a similar fall or, because of a change in the relative position of the system within the liquid crystal region, an increase.

The solubility of ascorbic acid in dispersions of polysorbate 80 has been examined. Over a large region of the solubility range liquid crystal exists, bounded by isotropic liquid phases. Excess solubilizate separates out as crystalline material. The rheological properties are complex. Within the isotropic phases the viscosity is Newtonian, but as soon as liquid crystal is produced pseudoplastic or thixotropic flow occurs. In the centre of the liquid crystal region, there were concentrations exhibiting a “yield” value followed by relaxation before the usual thixotropic loop.