The Test Product was more effective at reducing both the signs and symptoms of dry eye compared to the carboxymethylcellulose containing Control.

Summary This paper presents experimental results related to hydraulic fracturing of a horizontal well, specifically the nonplanar fracture geometries resulting from fracture initiation and propagation. Experiments were designed to investigate nonplanar fracture geometries which were categorized as: multiple parallel fractures, T-shaped fractures, and reoriented fractures. This paper discusses how these nonplanar fractures can be responsible for premature screen out and excessive treatment pressure when a horizontal well is hydraulically fractured. Reasons for unsuccessful hydraulic fracturing treatments of a horizontal well are presented and recommendations to ensure clear communication channel between the wellbore and the fracture are given. Fracture initiation pressure is a function of the wellbore orientation relative to the maximum horizontal stress. It is maximum when the horizontal well is drilled in the direction of the minimum horizontal stress. Extension pressure, however, shows little variation with respect to the wellbore direction. Experimental data shows that a relationship between breakdown pressure and wellbore orientation exists and can be used for wellbore stability problems. Microfrac analysis has been applied on the experimental data and showed that care must be exercised to determine closure pressure from a microfrac test performed on a horizontal well. A new phenomenon, "Relief in Pressure (RIP)", is presented to help determine the fracture azimuth relative to the wellbore from observing the pressure behavior after breakdown. The results of these openhole experiments can also be used for perforation design in cased holes to obtain a successful hydraulic fracturing treatment. Optimum perforated interval length and perforation phasing should follow the fracture azimuth at the wellbore as ft initiates from a given horizontal well. Introduction Horizontal wells have been drilled to increase the effective drainage area as compared to a vertical well, which can penetrate a smaller portion of the same reservoir. A horizontal well is fractured to improve productivity. Fracturing a horizontal well has sometimes been a dilemma during the last few years with occurrence of premature screenouts and high treatment pressures. This work identifies some of the problems, and suggests some solutions. In most geological formations, the orientation angle of a horizontal well from the maximum horizontal stress plays a crucial role in achieving a successful stimulation treatment. The following three mechanisms related to wellbore orientation relative to the maximum horizontal stress (orientation angle), need to be addressed.Fracture-wellbore communication area. Two extreme cases, longitudinal and orthogonal fractures, provide maximum and minimum communication area between the wellbore and propagating fractures.Fracture geometry near the wellbore. Important factor that may cause early screenouts. Several different fracture geometries can result when a horizontal well is fractured, among which are multiple fractures, T-shaped fractures, and complex fractures.Fracture tortuosity near the wellbore.

No abstract

Meibum is the primary component of the tear film lipid layer. Thought to play a role in tear film stabilization, understanding the physical properties of meibum and how they change with disease will be valuable in identifying dry eye treatment targets. Grazing incidence X-ray diffraction and X-ray reflectivity were applied to meibum films at an air-water interface to identify molecular organization. At room temperature, interfacial meibum films formed two coexisting scattering phases with rectangular lattices and next-nearest neighbor tilts, similar to the Ov phase previously identified in fatty acids. The intensity of the diffraction peaks increased with compression, although the lattice spacing and molecular tilt angle remained constant. Reflectivity measurements at surface pressures of 18 mN/m and above revealed multilayers with d-spacings of 50 Å, suggesting that vertical organization rather than lateral was predominantly affected by meibum-film compression.

The tear product containing HP-guar, PEG 400 and propylene glycol satisfies several pre-clinical criteria for an appropriate artificial tear formulation. It gives long-term desiccation protection of the intact cornea and also epithelial cells in culture and has no apparent deleterious affects on cells. It also provides conditions in which a damaged corneal epithelium can recover normal barrier function. The combination of ingredients in the formulation appears to provide an effective mucomimetic artificial tear product. These pre-clinical data suggest that the product will be effective in providing superior relief for the dry eye sufferer.

OPTI-FREE Express and OPTI-FREE RepleniSH multipurpose disinfecting solutions maintained fungicidal efficacy after storage of lenses. The Alexidine- and PHMB-based multipurpose solutions tested showed significant uptake of preservative into group IV lenses, resulting in a decrease in the residual activity of the storage solution. The POLYQUAD systems showed a low uptake of biocide and maintained fungicidal efficacy against F. solani.

More than two-fold RT differences were found for the higher viscosity, more muco-adhesive formulations compared to saline. However, other formulations provided RTs close to saline, suggesting that RT is influenced by factors other than simple viscosity. Future studies should examine the interplay of spreading characteristics, pseudoplasticity and muco-adhesion relative to RT to determine the individual and cumulative effects on formulation retention.

BackgroundThe purpose of this study was to assess whether differences in central corneal dendritic immune cell densities associated with combinations of soft contact lenses and lens care solutions could be detected by in vivo confocal microscopy.MethodsParticipants were adults naïve to contact lens wear (n = 10) or who wore soft contact lenses habitually on a daily-wear schedule (n = 38) or on a study-assigned schedule for 30 days with daily disposable silicone hydrogel lenses (n = 15). Central corneas were scanned using an in vivo confocal microscope. Cell densities were compared among groups by demographic parameters, lens materials, and lens care solutions (polyhexamethylene biguanide [PHMB], polyquaternium-1 and myristamidopropyl dimethylamine [PQ/MAPD], peroxide, or blister pack solution [for daily disposable lenses]).ResultsAmong lens wearers, no associations were observed between immune cell densities and age, gender, or years of lens-wearing experience. Mean cell density was significantly lower (P < 0.01) in nonwearers (29 ± 23 cells/mm2, n = 10) than in lens wearers (64 ± 71 cells/mm2, n = 53). Mean cell density was lower (P = 0.21) with traditional polymer lenses (47 ± 44 cells/mm2, n = 12) than with silicone hydrogel lenses (69 ± 77 cells/mm2, n = 41). Lowest to highest mean density of immune cells among lens wearers was as follows: PQ/MAPD solution (49 ± 28 cells/mm2), blister pack solution (63 ± 81 cells/mm2), PHMB solution (66 ± 44 cells/mm2), and peroxide solution (85 ± 112 cells/mm2).ConclusionIn this pilot study, in vivo confocal microscopy was useful for detecting an elevated immune response associated with soft contact lenses, and for identifying lens-related and solution-related immune responses that merit further research.