Extended Range of Vision IOL

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A clinical assessment of visual performance of combining the TECNIS<sup>&reg;</sup>&nbsp;Symfony&nbsp;Extended Range of Vision IOL (ZXR00) with the +3.25 D TECNIS Multifocal 1-piece IOL (ZLB00) in subjects undergoing bilateral cataract extraction

A clinical assessment of visual performance of combining the TECNIS<sup>&reg;</sup>&nbsp;Symfony&nbsp;Extended Range of Vision IOL (ZXR00) with the +3.25 D TECNIS Multifocal 1-piece IOL (ZLB00) in subjects undergoing bilateral cataract extraction

The IOLs used in this study were the TECNIS Symfony IOL (ZXR00) in the dominant eye and a + 3.25 D (ZLB00) TECNIS MF 1-piece IOL in the non-dominant eye. Both models are posterior, 1-piece, soft-foldable acrylic, UV- absorbing, diffractive IOLs (Package Insert TECNIS Sym- fony IOL, Package Insert ZLB00 IOL; Abbott Medical Optics, Inc.). Both lenses also have a biconvex optic that incorporates a wavefront-designed aspheric optic to compen- sate for corneal spherical aberration, and both have a square posterior edge design with a frosted optic edge. The IOLs differ in the posterior optic design in that the ZXR00 IOL pos- terior optic includes an achromatic diffractive surface on the posterior optic to correct chromatic aberration and a unique echelette feature to extend the range of vision, including

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Rotational stability and visual performance 3 months after bilateral implantation of a new toric extended range of vision intraocular lens

Rotational stability and visual performance 3 months after bilateral implantation of a new toric extended range of vision intraocular lens

A 2.2 mm self-sealing incision at the 12 o’clock position and a 5.5 mm continuous curvilinear capsulorhexis were created in all cases using the Verion video overlay as a guidance. The natural lens was removed by phacoemulsification. The toric lens was then implanted in the bag using the UNFOLDER Platinum 1 Series Screw-Style injector (Johnson & Johnson Vision) and rotated clockwise to approximately 10 degrees short of the desired position. The desired axis of alignment was calculated using the Barrett formula and shown intra- operatively as a video overlay using the Verion guidance system. After IOL insertion and ophthalmic viscoelastic device (OVD) removal, the toric IOL was rotated with a sec- ond instrument to its final position. Postoperatively, patients were prescribed Tobrasone (Alcon Laboratories, Inc.) and Nevanac (Novartis Pharmaceuticals UK Ltd; Camberley, UK) eye drops four times daily tapered over 20 days.

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Tecnis Symfony Intraocular Lens with a “Sweet Spot” for Tolerance to Postoperative Residual Refractive Errors

Tecnis Symfony Intraocular Lens with a “Sweet Spot” for Tolerance to Postoperative Residual Refractive Errors

In the CONCERTO study, the Tecnis Symfony IOL provided a homogeneous and excellent visual restoration across all distances after cataract surgery or clear lens exchange, with minimal levels of disturbing photic phenomena [8]. Previ- ous theoretical and in - vitro studies have demonstrated that the combination of the compensation for chromatic aberration, primary spherical aberration and unique echellette design results in an increased ability to provide an extended range of vision [9] [10] [11]. Also, the light distribution of the Tecnis Symfony IOL between its best vision foci has been demonstrated to be more homogene- ous and less vergence dependent under dim conditions compared to multifocal IOLs [12]. This special optical design allows excellent optical and visual out- comes for far and intermediate distances, and a functional range of VA for near. According to our results, residual cylinders up to 0.75 D after the implanta- tion of the Tecnis Symfony IOL have a very mild and clinically insignificant im- pact on monocular and binocular UDVA. Likewise, binocular UIVA and UNVA are not significantly affected in this situation. The orientation of the residual astigmatism does not seem to have either a significant impact on the visual out- come achieved with the Tecnis Symfony IOL, with similar UDVA, UIVA and UNVA in eyes with WTR, ATR and OBL astigmatisms. Regarding the postop- erative SE, the Tecnis Symfony IOL shows a good tolerance to unexpected re- fractive surprises and thus a better “sweet spot”.

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Influence of the level of monovision on visual outcome with an extended range of vision intraocular lens

Influence of the level of monovision on visual outcome with an extended range of vision intraocular lens

We found the overall best results in monovision levels of 0.5 to #0.75 D and 0.75 to #1.0 D, which indicates that a mini-monovision of around 0.75 D in eyes implanted bilaterally with the ERV IOL Tecnis Symfony may provide the optimum visual rehabilitation after cataract surgery, with good levels of visual acuity across all distances, minimal incidence of photic phenomena, and high levels of patient satisfaction. Monovision levels .0.75 D resulted in slightly worse intermediate visual acuity. Future studies should evaluate the impact of mini-monovision on stereopsis and the long-term outcome with this approach.

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<p>Visual quality and performance following bilateral implantation of TECNIS Symfony intraocular lenses with or without micro-monovision</p>

<p>Visual quality and performance following bilateral implantation of TECNIS Symfony intraocular lenses with or without micro-monovision</p>

insuf fi cient visual acuity. 3,4 Currently, various MIOLs still have some de fi ciencies in terms of presbyopia correction. Finding better concepts for MIOLs is therefore a major goal of current research. 5,6 The TECNIS Symfony extended range of vision (ERV) IOL (Johnson & Johnson Vision, Santa Ana, CA, USA) is a new-generation presbyopia- correcting IOL, which is supposed to offer an improved visual quality and less photic phenomena compared to for- mer MIOLs. In addition, this lens is designed to provide a continuous range of functional vision from far to near distances. Clinical studies with TECNIS Symfony IOLs demonstrated excellent distance and intermediate visual outcomes but it was also reported that visual results were somewhat limited at near distances. 7,8

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<p>Refractive and Visual Outcomes After Bilateral Implantation of a Trifocal Intraocular Lens in a Large Population</p>

<p>Refractive and Visual Outcomes After Bilateral Implantation of a Trifocal Intraocular Lens in a Large Population</p>

One of the newer trifocal IOL designs available is the AcrySof ® IQ PanOptix Trifocal IOL (Alcon, Fort Worth, TX, USA). It is based on a quadrifocal optical principle, with the second focal point relatively suppressed. This allowed the best focus intermediate to be at 60 cm rather than 80 cm – the latter is a typical intermediate design distance for a standard trifocal IOL if the near point is 40 cm. This trifocal IOL has been reported to provide improved intermediate vision when compared to a bifocal IOL, without negatively impacting contrast sensitivity. 4 This trifocal design has been compared with different trifocal designs, an extended depth of focus IOL and a bifocal IOL and some advantages with regard to range of vision and visual disturbances have been reported. This IOL was shown to provide improved intermediate vision at 60 cm with fewer complaints of halos when compared with another trifocal IOL. 5 Near vision is also reportedly better when compared to an extended depth of focus IOL. 6

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Power Supply Quality Improvement With An Extended Range Domestic Voltage Requlators

Power Supply Quality Improvement With An Extended Range Domestic Voltage Requlators

THE problems encountered by consumers in the Nigerian power supply system are numerous. However, a major problem is the quality of power supplied. The availability of adequate supplies of electricity at the nominal level of 220 volts for domestic purposes is a matter of great concern throughout Nigeria. In the pre – oil boom era the quality of power as characterized by the supply voltage closely matched the nominal values. However the boom led to a phenomenal growth of demand in power which was met by crash supplies of expansion of the distribution lines often times without the commensurate upgrading of the supply transformers. In some cases larger transformers were installed to feed loads located further and further away from the sub – station (Olufeagba, 2006). The net result of this is that consumers in different parts of an area receive voltages far removed from the nominal values. Consequently a burgeoning market for automatic stabilizers and regulators rated between 0.5 KVA and 10 KVA for the domestic market has grown. The devices have various advertised performance limitations and employ a combination of electronics to select the tappings on transformers. In an ideal situation, voltages no less than 170 volts can be readily taken care of with outputs lying within the stipulated tolerance of the supply authority’s values. Unfortunately, the unrestricted expansion of the distribution networks has led to extremely low voltages so that the typical commercially available voltage regulators are not effective for restoring some sort of acceptable operating voltage. A preliminary study carried out during this research and reported below, reveals that the situation in practice is much worse with consumer voltages as low as 50 volts being quite possible (Olufeagba, 2006). Statistical data reveal that 22% of stabilizers purchased by consumers did not perform satisfactorily when the input supply voltage was less than 160 volts. Products like Qlinks, Binatone, Philips, Super Masters, Century etc, regulate input voltage that falls within 160 volts and 260 volts, a range that does not cater for the Nigerian buyer (Ogunlade, 1999). 2.1. The Objectives of the Research

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Calibration of Multiple Poliovirus Molecular Clocks Covering an Extended Evolutionary Range

Calibration of Multiple Poliovirus Molecular Clocks Covering an Extended Evolutionary Range

isolates may be used to estimate their total time of evolution- ary separation for up to ⬃ 20 years. Pairwise transversion dif- ferences can be used without correction for time estimates of up to 20 years, but transition differences require correction for time estimates in the 10- to 20-year range. Because no contin- uous, well-defined poliovirus lineages with isolates having more than 20 years of total evolutionary separation have been identified, we cannot rigorously apply the above approach be- yond 20 years. Therefore, we applied mathematical modeling to simulate the evolution of P1/capsid 3CP substitutions from the VEN81-1 root (see Fig. S2 in the supplemental material) in order to investigate the saturation kinetics of transitions and transversions over an ⬃ 100-year period (Fig. 7C). Simulations were performed by using the program mutate in MATLAB, applying the initial 3CP base distribution vector for VEN81-1 and a substitution matrix based upon the relative frequencies of specific base changes given in Fig. 5, but with the transver- sion frequencies increased 1.8-fold to correct for the observa- tion that only ⬃ 56% of P1/capsid 3CPs were fourfold degen- erate sites. Simulations were performed for a total of 200 time steps (equivalent to ⬃ 6 months of evolution per time step), and the abscissa of the plot of the simulated saturation curves FIG. 7. Saturation of 3CP transitions (closed circles), 3CP transversions (open circles), and total 3CP substitutions (triangles) in the P1/capsid region over the total period of independent evolution of the northern and southern lineages. (A) Uncorrected pairwise 3CP differences between all 31 isolates (ordinate) were plotted as a function of time of evolutionary separation (estimated from branch lengths of the ML/SRDT tree [Fig. 1]). (B) Pairwise 3CP differences corrected by use of the REV model of nucleotide substitution. (C) Simulation of saturation of 3CP transitions (closed circles), 3CP transversions (open circles), and total 3CP substitutions (triangles) in the P1/capsid region over a 100-year period, calculated by using the mutate program in MATLAB as described in Materials and Methods. The boxed area represents the time interval shown in panels A and B.

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The spectral input to honeybee visual odometry

The spectral input to honeybee visual odometry

Bees returning from a feeder placed in a narrow tunnel that is lined with a chequered pattern will strongly overestimate travel distance. This finding supports the view that their distance estimation is based on integrating optic flow experienced during flight. Here, we use chequered tunnels with various colour combinations as a tool to identify the spectral channel used by bees to gauge travel distance. The probability of bees performing waggle dances after a short travel distance correlates only with the low range of the green contrast of the pattern in the tunnel. But it does not correlate with the pattern’s

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VISION IN THE CTENID SPIDER CUPIENNIUS SALEI: SPECTRAL RANGE AND ABSOLUTE SENSITIVITY

VISION IN THE CTENID SPIDER CUPIENNIUS SALEI: SPECTRAL RANGE AND ABSOLUTE SENSITIVITY

Electroretinograms were recorded from all eyes of the wandering spider Cupiennius salei (Ctenidae) and were found to be simple cornea-negative potential differences with amplitudes of up to 10mV. In both the principal eyes and all of the secondary eyes, the spectral response curves show a prominent green peak at 520 or 540nm and a shoulder in the ultraviolet between 340 and 380nm. The largest response in the ultraviolet measures between 65% and 80% of the green peak. Selective chromatic adaptation to either green or ultraviolet monochromatic light does not change these relative response levels and fails to indicate the presence of more than one spectral type of receptor. In the range 450–500nm, however, the Dartnall curve clearly deviates from the spectral sensitivity (SS) curve. Since the SS curves of all eyes have a small shoulder in the blue at 480nm, the existence of two or even three visual pigments is a possibility. Intensity curves were determined with white and monochromatic light. For white light, absolute corneal illuminance thresholds were clearly below 0.01lx. For monochromatic light stimuli, a corneal illuminance of approximately 3 3 10 12 photonscm 22 s 21 is needed to elicit a half-

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Covariance Operators and the Central Limit Theory for "Loop" Markov Chains

Covariance Operators and the Central Limit Theory for "Loop" Markov Chains

The shape of this distribution that is similar to that of normal distribution has made it to be preferred to normal distribution by some researchers like Berkson (1944,1950,1953 ), Berkson and Hodges (1960) etc. Ojo (1989) used the logistic model to analyze some social problem data. Researchers have been working on order statistics from the logistic distribution over time. It was considered in Plackett (1958), Birnbaum and Dudman (1963), Tarter and Clark (1965), Shuah (1966, 1970), Gupta, Qureishi and Shah (1967) obtain best unbiased estimated estimators of the location and scale parameters of the logistic distribution using order statistics. It is well known that range and quasi- range are important statistics that depend on order statistics. Gupta and Shah (1965) obtained the distribution of the range from the logistic distribution while Malik (1980) obtained the distribution function of the quasi-range from the logistic distribution.

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High power density STATCOM with extended reactive power control range

High power density STATCOM with extended reactive power control range

Abstract—This paper proposes a new configuration for static synchronous compensator (STATCOM) based on the ac-side voltage doubling voltage source converter (ACVD-VSC), which has twice of the dc-link voltage utilization as two-level VSC, hence improved power density per unit dc-link voltage. This means its dc voltage limit for reactive power generation is higher than that using conventional two-level VSC. Therefore, extended reactive power control range is resulted for the proposed solution. Also the ACVD converter has zero dc common mode voltage between the ac neutral point and the dc-link negative terminal, reducing the insulation level for the interfacing transformer when the negative dc bus is grounded. The basic operation principles of ACVD-VSC are reviewed. Then, it is used to perform voltage or power flow control as shunt compensators.

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Optical system for measuring the spectral retardance function in an extended range

Optical system for measuring the spectral retardance function in an extended range

As linear polarizers (P1 and P2) we use two high- quality calcite Glan-Taylor cube polarizers from Edmund Optics, covering a spectral range from 350 to 2200 nm, with a nominal extinction ratio less than 5 × 10 -6 . This kind of polarizers is required since common commercial polaroid sheets do not act properly as polarizers in the IR range. They have been mounted on rotatable mounts, so the angle of the transmission axis can be rotated con- tinuously. The retarder to be characterized is placed in between the two polarizers. Then, the transmitted light is divided in two beams by means of a B270 Glass Polka Dot beam-splitter from Thorlabs. Again, this kind of beam-splitter is required since it operates in a wide range of wavelengths from 350 nm to 2.0 μm. These two

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Extended Range of Stable Radial Position of Tokamak Plasma in TOKASTAR-2

Extended Range of Stable Radial Position of Tokamak Plasma in TOKASTAR-2

The original PVF coil set, a so-called Helmholtz coil, generates a nearly flat vertical field between the inner and outer limiters, which satisfies the stability condition 0 < n < 1.5 in a wide range of 75 mm ≤ R ≤ 160 mm. A large eddy current is, however, generated in the TOKASTAR-2 vacuum vessel by the loop voltage induced by the OH coil current [3]. The vertical field generated by the eddy cur- rent is nearly uniform and in the opposite direction to the vertical field generated by the PVF coil current and cancels more than half of it. As a result, the vertical field becomes zero near the surface of the outer limiter (R = 172 mm) as shown by a blue curve in Fig. 6 (a) and the range with n < 1.5 is restricted to R < 120 mm as shown by a blue curve in Fig. 6 (b). This may restrict the possible opera- tion range of the plasma position to the inner region. In contrast, the helical field is stronger in the outer region as shown in Fig. 7 and hence experiment with tokamak plasma in the outer region is preferable to see the effect

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Vertical transmission of Indian Ocean Lineage of chikungunya virus in Aedes aegypti and Aedes albopictus mosquitoes

Vertical transmission of Indian Ocean Lineage of chikungunya virus in Aedes aegypti and Aedes albopictus mosquitoes

use of CHIKV IOL-free mosquitoes is to ensure that the virus infection in both mosquito species occurred from our experiment. As determined by visual inspection, most of the mosquitoes in the cage were fully engorged and laid all their eggs by 5–6 days post-infection. The later oviposition provided a chance to obtain the eggs in- fected with CHIKV IOL which is in accordance with the previous study revealing that the Ae. albopictus eggs be- came infected with the virus at day 6 post-infection [17]. The mean MIRs determined in this study were highest in the F1 generation of Ae. aegypti (8.33 ± 2.887, 1:120 for larvae and 10.00 ± 3.333, 1:100 for adults) and Ae. albopictus (18.33 ± 3.333, 1:54.5 for larvae and 21.67 ± 2.887, 1:46.2 for adults). Such high MIRs in that gener- ation were similar to the preceding evidence that showed the highest MIR in the F1 generation of Ae. aegypti infected with DENV 2 [49]. This high MIR could be used as an indicator of potential outbreaks. Our re- sult also revealed that the MIRs determined in early gen- erations of Ae. aegypti and Ae. albopictus adults were higher than those measured in their larvae. It was due to the amplification of virus following transition from lar- vae to adult stage [34]. However, there was fluctuation of MIR observed in larvae from the F3 generation of Ae. aegypti and the F5 generation of Ae. albopictus. This was feasible because of the different number of eggs obtained each generation of the mosquitoes and the ran- dom sampling of progeny from virus-positive mosqui- toes which might result in a minor variation in MIR of those generations. Nevertheless, the CHIKV RNA titer measured in the F1 generation of Ae. aegypti and Ae. albopictus was low, peaked at the F2 generation and de- creased subsequently to be undetectable to the F6–F9 generations and the F7–F9 generations of Ae. aegypti and Ae. albopictus, respectively. A low amount of CHIKV RNA titer determined in the larvae and adults of Ae. aegypti and Ae. albopictus from the F1 generation was due to low viral infection in eggs that the most eggs were laid prior to day 6 post-infection. Furthermore, the adaptation between the virus and the mosquitoes may be associated with such low CHIKV RNA titer from the initial generation. The viral titer increased up to the F2 generation, however, it decreased subsequently in the later generations of the two mosquito species that may be involved with the genetic factors of both virus and mosquitoes including the selection pressure under la- boratory conditions. The present study showed that the viral RNA titer was not significantly different among generations of Ae. aegypti larvae, whereas it revealed a significant difference among generations of Ae. aegypti adults, Ae. albopictus larvae and Ae. albopictus adults. The viral RNA titers determined in Ae. aegypti adults and Ae. albopictus adults were significantly higher than those measured in Ae. aegypti larvae and Ae. albopictus

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Murine Coronavirus with an Extended Host Range Uses Heparan Sulfate as an Entry Receptor

Murine Coronavirus with an Extended Host Range Uses Heparan Sulfate as an Entry Receptor

strated a correlation between 21 amino acid substitutions and the 7-amino-acid insert, all located in the S1 domain, with the extended host range (32). However, although introduction of these mutations into an isogenic background permitted MHV- A59 to interact with alternative receptors on murine and non- murine cells, these viruses failed to induce a second round of infection in nonmurine cells under liquid medium, indicating that additional substitutions in S or mutations in other viral genes may be needed for efficient infection of these cells (35). These studies raised the questions of how these viruses have overcome the apparent dependence on a specific receptor and by what interactions the S protein is triggered to undergo the conformational changes required to initiate the fusion process. In the present study, we determined the attachment/entry re- ceptor of the extended host range variant generated by Sawicki and coworkers (MHV/BHK). In addition, we demonstrated that the S gene of MHV/BHK is sufficient to confer the ex- tended host range phenotype.

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Approximations to the Normal Distribution Function and An Extended Table for the Mean Range of the Normal Variables

Approximations to the Normal Distribution Function and An Extended Table for the Mean Range of the Normal Variables

New methods for the approximation of the normal distribution func- tion have been introduced. The accuracy and the speed of the cal- culations are advantages of the proposed methods over the some ex- isting methods. An extended table for the mean range of the normal variables has been constructed.

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Study of infrared photodetectors with wavelength extension mechanism

Study of infrared photodetectors with wavelength extension mechanism

the barrier offset is a critical requirement for the extended wavelength photoresponse, and the graded barrier shows higher extended wavelength photoresponse. In addition, the barrier energy offset increased from 0.10 eV to 0.19 eV enables increased photoresponse and optimized operating condition over a wide applied bias range. Furthermore, a comparison of dark current with a conventional detector shows a significant dark current advantage due to the extended wavelength mechanism.

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Dynamic interferometric measurement with extended unambiguity range in flow measurement

Dynamic interferometric measurement with extended unambiguity range in flow measurement

Interferometric methods such as digital holographic interferometry and interferometry are generally understood to belong to the group of most accurate measuring devices [1]. Their fundamental measure is the wavelength of light and the todays interferometer can resolve even a fraction of the wavelength, so their sensitivity is outstanding. Due to their great accuracy interferometers in different variations are used in many branches of measurement including the fluid mechanics. However, due to the bounded nature of a light wave, the measurement range given by the unambiguity is squeezed within the range of one cycle of the wave. Measured phase maps are therefore wrapped within the range of 2π radians.

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Extended LaSalle's Invariance Principle for Full-Range Cellular Neural Networks

Extended LaSalle's Invariance Principle for Full-Range Cellular Neural Networks

The Full-Range (FR) model of cellular neural networks (CNNs) has been introduced in [1] in order to obtain advantages in the VLSI implementation of CNN chips with a large number of neurons. One main feature is the use of hard-limiter nonlinearities that constrain the evolution of the FR-CNN trajectories within a closed hypercube of the state space. This improved range of the trajectories has enabled us to reduce the power consumption and obtain higher cell densities and increased processing speed [1–4] compared to the original standard (S) CNN model by Chua and Yang [5].

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