Requirement for and optimisation of premium intraocular lenses

Premium intraocular lenses (IOLs) aim to surgically correct astigmatism and presbyopia following cataract extraction, optimising vision and eliminating the need for cataract surgery in later years. It is usual to fully correct astigmatism and to provide visual correction for distance and near when prescribing spectacles and contact lenses, however for correction with the lens implanted during cataract surgery, patients are required to purchase the premium IOLs and pay surgery fees outside the National Health Service in the UK. The benefit of using toric IOLs was thus demonstrated, both in standard visual tests and real-world situations. Orientation of toric IOLs during implantation is critical and the benefit of using conjunctival blood vessels for alignment was shown. The issue of centration of IOLs relative to the pupil was also investigated, showing changes with the amount of dilation and repeat dilation evaluation, which must be considered during surgery to optimize the visual performance of premium IOLs. Presbyopia is a global issue, of growing importance as life expectancy increases, with no real long-term cure. Despite enhanced lifestyles, changes in diet and improved medical care, presbyopia still presents in modern life as a significant visual impairment. The onset of presbyopia was found to vary with risk factors including alcohol consumption, smoking, UV exposure and even weight as well as age. A new technique to make measurement of accommodation more objective and robust was explored, although needs for further design modifications were identified. Due to dysphotopsia and lack of intermediate vision through most multifocal IOL designs, the development of a trifocal IOL was shown to minimize these aspects. The current thesis, therefore, emphasises the challenges of premium IOL surgery and need for refinement for optimum visual outcome in addition to outlining how premium IOLs may provide long-term and successful correction of astigmatism and presbyopia.

Universities and the user community:marriage or mismatch?

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Evaluating techniques to improve visual performance with and assessment of premium intraocular lenses

Premium Intraocular Lenses (IOLs) such as toric IOLs, multifocal IOLs (MIOLs) and accommodating IOLs (AIOLs) can provide better refractive and visual outcomes compared to standard monofocal designs, leading to greater levels of post-operative spectacle independence. The principal theme of this thesis relates to the development of new assessment techniques that can help to improve future premium IOL design. IOLs designed to correct astigmatism form the focus of the first part of the thesis. A novel toric IOL design was devised to decrease the effect of toric rotation on patient visual acuity, but found to have neither a beneficial or detrimental impact on visual acuity retention. IOL tilt, like rotation, may curtail visual performance; however current IOL tilt measurement techniques require the use of specialist equipment not readily available in most ophthalmological clinics. Thus a new idea that applied Pythagoras’s theory to digital images of IOL optic symmetricality in order to calculate tilt was proposed, and shown to be both accurate and highly repeatable. A literature review revealed little information on the relationship between IOL tilt, decentration and rotation and so this was examined. A poor correlation between these factors was found, indicating they occur independently of each other. Next, presbyopia correcting IOLs were investigated. The light distribution of different MIOLs and an AIOL was assessed using perimetry, to establish whether this could be used to inform optimal IOL design. Anticipated differences in threshold sensitivity between IOLs were not however found, thus perimetry was concluded to be ineffective in mapping retinal projection of blur. The observed difference between subjective and objective measures of accommodation, arising from the influence of pseudoaccommodative factors, was explored next to establish how much additional objective power would be required to restore the eye’s focus with AIOLs. Blur tolerance was found to be the key contributor to the ocular depth of focus, with an approximate dioptric influence of 0.60D. Our understanding of MIOLs may be limited by the need for subjective defocus curves, which are lengthy and do not permit important additional measures to be undertaken. The use of aberrometry to provide faster objective defocus curves was examined. Although subjective and objective measures related well, the peaks of the MIOL defocus curve profile were not evident with objective prediction of acuity, indicating a need for further refinement of visual quality metrics based on ocular aberrations. The experiments detailed in the thesis evaluate methods to improve visual performance with toric IOLs. They also investigate new techniques to allow more rapid post-operative assessment of premium IOLs, which could allow greater insights to be obtained into several aspects of visual quality, in order to optimise future IOL design and ultimately enhance patient satisfaction.

Trading-up on unmet expectations? Evaluating consumers’ expectations in online premium grocery shopping logistics

Geography and retail store locations are inherently bound together; this study links food retail changes to systemic logistics changes in an emerging market. The later include raising income and education, access to a wide range of technologies, traffic and transport difficulties, lagging retail provision, changing family structure and roles, as well as changing food culture and taste. The study incorporates demand for premium products defined by Kapferer and Bastien [2009b. The Luxury Strategy. London: Kogan Page] as comprising a broad variety of higher quality and unique or distinctive products and brands including in grocery organic ranges, healthy options, allergy free selections, and international and gourmet/specialty products through an online grocery model (n = 356) that integrates a novel view of home delivery in Istanbul. More importantly from a logistic perspective our model incorporates any products from any online vendors broadening the range beyond listed items found in any traditional online supermarkets. Data collected via phone survey and analysed via structural equation modelling suggest that the offer of online premium products significantly affects consumers’ delivery logistics expectations. We discuss logistics operations and business management implications, identifying the emerging geography of logistic models which respond to consumers’ unmet expectations using multiple sourcing and consolidation points.

The unhappy marriage of religion and politics:problems and pitfalls for gender equality

This article explores how religion as a political force shapes and deflects the struggle for gender equality in contexts marked by different histories of nation building and challenges of ethnic diversity, different state–society relations (from the more authoritarian to the more democratic), and different relations between state power and religion (especially in the domain of marriage, family and personal laws). It shows how ‘private’ issues, related to the family, sexuality and reproduction, have become sites of intense public contestation between conservative religious actors wishing to regulate them based on some transcendent moral principle, and feminist and other human rights advocates basing their claims on pluralist and time- and context-specific solutions. Not only are claims of ‘divine truth’ justifying discriminatory practices against women hard to challenge, but the struggle for gender equality is further complicated by the manner in which it is closely tied up with, and inseparable from, struggles for social and economic justice, ethnic/racial recognition, and national self-determination vis-à-vis imperial/global domination.

A bizonytalanságnak és a vevőkör nagyságának együttes hatása az árakra (Investigating how the number of policies effect the optimum insurance premium)

Ebben a cikkben azzal foglalkozom, hogy a kockázat és a vevőkör nagysága együttesen hogyan hat a termék árára. Kétféle piacot hasonlítok össze: egy biztosítási piacot, és egy termékpiacot. A kétféle piac között az a legfontosabb különbség, hogy termékpiac esetében az eladó számára csak ott jelentkezik kockázat, hogy el tudja-e adni a terméket, míg biztosítási piac esetében az eladó a termék értékesítése után is szembesül kockázattal. A cikk során megmutatom, hogy a vevőkör növekedésének ellentétes hatása lehet a termék árára termék- illetve biztosítási piacok esetében. / === / An economic approach for modeling the insurance markets. The study focuses on the monopolistic market, where one insurance company sells a product with predetermined benefits for the customers. An outline of the company and the insureds' behavior with utility functions is given. The study investigates the problem of policy pricing in relation to the number of clients the company acquires. Analytic tools will be used to further clarify the points.

A man with an "equal rights for fathers" sign attends the "Marriage and Divorce" conference

General note: Title and date provided by Bettye Lane.

Marriage and divorce demonstration at Brides Magazine

General note: Title and date provided by Bettye Lane.

Cigar smoking masked woman testifies at "Marriage and Divorce" conference

General note: Title and date provided by Bettye Lane.

Mothers but not wives: The increasing lag between nonmarital births and marriage

This study analyzed trends in marital behavior for unwed mothers who gave birth between 1960 and 2004. With nationally representative data on 15,353 White and Black unmarried mothers, results indicated that mothers who gave birth after 1989 were waiting much longer to marry than were mothers giving birth before 1968. The most pronounced delays were found immediately after a birth. Over the study period, the cumulative proportion of women who married within three years of a birth decreased for Whites by 27% and for Blacks by 60%. Findings underscore the separation that has developed between first births and first marriages in the United States, and they highlight the older ages at which children are experiencing a transition to marriage. © National Council on Family Relations, 2011.

Introducing "Fourth Space" : Young Muslims Negotiating Marriage in Europe

Based on interviews with young persons in two national Muslim youth organizations in Europe, this article examines how young Muslims negotiate between the cultural customs of their societiesof origin, their everyday experiences in Europe, and the global Muslim public sphere. In seekinga universal “true” core of Islam, these young persons create their own version of Islam, a “fourthspace” in which they reinterpret the authoritative source texts of Islam in light of personal diasporicexperiences in Europe. This reinterpretation becomes particularly pertinent in the context of planningfor future marriage, where they jointly construct new understandings of Islam to argue for inter-ethnic marriages and later age at marriage, to argue against coercion in arranged marriages, tooppose polygyny and to portray the stigmatization of divorce as counter to the true spirit of Islam.

Future Earnings Growth Volatility and the Value Premium

The value premium is well established in empirical asset pricing, but to date there is little understanding as to its fundamental drivers. We use a stochastic earnings valuation model to establish a direct link between the volatility of future earnings growth and firm value. We illustrate that risky earnings growth affects growth and value firms differently. We provide empirical evidence that the volatility of future earnings growth is a significant determinant of the value premium. Using data on individual firms and characteristic-sorted test portfolios, we also find that earnings growth volatility is significant in explaining the cross-sectional variation of stock returns. Our findings imply that the value premium is the rational consequence of accounting for risky earnings growth in the firm valuation process.