Operator-induced errors in Hartmann-Shack wavefront sensing:model eye study

Purpose: To evaluate the effects of instrument realignment and angular misalignment during the clinical determination of wavefront aberrations by simulation in model eyes. Setting: Aston Academy of Life Sciences, Aston University, Birmingham, United Kingdom. Methods: Six model eyes were examined with wavefront-aberration-supported cornea ablation (WASCA) (Carl Zeiss Meditec) in 4 sessions of 10 measurements each: sessions 1 and 2, consecutive repeated measures without realignment; session 3, realignment of the instrument between readings; session 4, measurements without realignment but with the model eye shifted 6 degrees angularly. Intersession repeatability and the effects of realignment and misalignment were obtained by comparing the measurements in the various sessions for coma, spherical aberration, and higher-order aberrations (HOAs). Results: The mean differences between the 2 sessions without realignment of the instrument were 0.020 μm ± 0.076 (SD) for Z3 - 1(P = .551), 0.009 ± 0.139 μm for Z3 1(P = .877), 0.004 ± 0.037 μm for Z4 0 (P = .820), and 0.005 ± 0.01 μm for HO root mean square (RMS) (P = .301). Differences between the nonrealigned and realigned instruments were -0.017 ± 0.026 μm for Z3 - 1(P = .159), 0.009 ± 0.028 μm for Z3 1 (P = .475), 0.007 ± 0.014 μm for Z4 0(P = .296), and 0.002 ± 0.007 μm for HO RMS (P = 0.529; differences between centered and misaligned instruments were -0.355 ± 0.149 μm for Z3 - 1 (P = .002), 0.007 ± 0.034 μm for Z3 1(P = .620), -0.005 ± 0.081 μm for Z4 0(P = .885), and 0.012 ± 0.020 μm for HO RMS (P = .195). Realignment increased the standard deviation by a factor of 3 compared with the first session without realignment. Conclusions: Repeatability of the WASCA was excellent in all situations tested. Realignment substantially increased the variance of the measurements. Angular misalignment can result in significant errors, particularly in the determination of coma. These findings are important when assessing highly aberrated eyes during follow-up or before surgery. © 2007 ASCRS and ESCRS.

Wavefront analyzers induce instrument myopia

PURPOSE: To assess the accuracy of three wavefront analyzers versus a validated binocular open-view autorefractor in determining refractive error in non-cycloplegic eyes. METHODS: Eighty eyes were examined using the SRW-5000 open-view infrared autorefractor and, in randomized sequence, three wavefront analyzers: 1) OPD-Scan (NIDEK, Gamagori, Japan), 2) WASCA (Zeiss/Meditec, Jena, Germany), and 3) Allegretto (WaveLight Laser Technologies AG, Erlangen, Germany). Subjects were healthy adults (19 men and 21 women; mean age: 20.8 +/- 2.5 years). Refractive errors ranged from +1.5 to -9.75 diopters (D) (mean: +1.83 +/- 2.74 D) with up to 1.75 D cylinder (mean: 0.58 +/- 0.53 D). Three readings were collected per instrument by one examiner without anticholinergic agents. Refraction values were decomposed into vector components for analysis, resulting in mean spherical equivalent refraction (M) and J0 and J45 being vectors of cylindrical power at 0 degrees and 45 degrees, respectively. RESULTS: Positive correlation was observed between wavefront analyzers and the SRW-5000 for spherical equivalent refraction (OPD-Scan, r=0.959, P<.001; WASCA, r=0.981, P<.001; Allegretto, r=0.942, P<.001). Mean differences and limits of agreement showed more negative spherical equivalent refraction with wavefront analyzers (OPD-Scan, 0.406 +/- 0.768 D [range: 0.235 to 0.580 D] [P<.001]; WASCA, 0.511 +/- 0.550 D [range: 0.390 to 0.634 D] [P<.001]; and Allegretto, 0.434 +/- 0.904 D [range: 0.233 to 0.635 D] [P<.001]). A second analysis eliminating outliers showed the same trend but lower differences: OPD-Scan (n=75), 0.24 +/- 0.41 D (range: 0.15 to 0.34 D) (P<.001); WASCA (n=78), 0.46 +/- 0.47 D (range: 0.36 to 0.57 D) (P<.001); and Allegretto (n=77), 0.30 +/- 0.62 D (range: 0.16 to 0.44 D) (P<.001). No statistically significant differences were noted for J0 and J45. CONCLUSIONS: Wavefront analyzer refraction resulted in 0.30 D more myopia compared to SRW-5000 refraction in eyes without cycloplegia. This is the result of the accommodation excess attributable to instrument myopia. For the relatively low degrees of astigmatism in this study (<2.0 D), good agreement was noted between wavefront analyzers and the SRW-5000. Copyright (C) 2006 SLACK Incorporated

The rise and fall of the conglomerate

Conglomerates (broadly defined as companies with significant unrelated activities) experienced turbulent times over the last quarter of the 20th century in the US and the UK. In the US, conglomerate strategies were adopted by an increasing number of companies in the post-war period through to the 1980s. By 1970, 20% of the Fortune 500 were conglomerates, a percentage that remained broadly constant through to the late 1980s when both academic and business writers increasingly began to criticise the rationale behind conglomeration, and many companies began to seek greater focus.

Elementary units of cortical activity? The rise and fall of the cortical column

The roots of the concept of cortical columns stretch far back into the history of neuroscience. The impulse to compartmentalise the cortex into functional units can be seen at work in the phrenology of the beginning of the nineteenth century. At the beginning of the next century Korbinian Brodmann and several others published treatises on cortical architectonics. Later, in the middle of that century, Lorente de No writes of chains of ‘reverberatory’ neurons orthogonal to the pial surface of the cortex and called them ‘elementary units of cortical activity’. This is the first hint that a columnar organisation might exist. With the advent of microelectrode recording first Vernon Mountcastle (1957) and then David Hubel and Torsten Wiesel provided evidence consistent with the idea that columns might constitute units of physiological activity. This idea was backed up in the 1970s by clever histochemical techniques and culminated in Hubel and Wiesel’s well-known ‘ice-cube’ model of the cortex and Szentogathai’s brilliant iconography. The cortical column can thus be seen as the terminus ad quem of several great lines of neuroscientific research: currents originating in phrenology and passing through cytoarchitectonics; currents originating in neurocytology and passing through Lorente de No. Famously, Huxley noted the tragedy of a beautiful hypothesis destroyed by an ugly fact. Famously, too, human visual perception is orientated toward seeing edges and demarcations when, perhaps, they are not there. Recently the concept of cortical columns has come in for the same radical criticism that undermined the architectonics of the early part of the twentieth century. Does history repeat itself? This paper reviews this history and asks the question.

Safety and health in mines: the rise of bureaucracy in the coal mining industry and its results as evidenced by the public enquiry into an accident at Houghton Main Colliery

This thesis is concerned with certain aspects of the Public Inquiry into the accident at Houghton Main Colliery in June 1975. It examines whether prior to the accident there existed at the Colliery a situation in which too much reliance was being placed upon state regulation and too Iittle upon personal responsibility. I study the phenomenon of state regulation. This is done (a) by analysis of selected writings on state regulation/intervention/interference/bureaucracy (the words are used synonymously) over the last two hundred years, specifically those of Marx on the 1866 Committee on Mines, and (b) by studying Chadwick and Tremenheere, leading and contrasting "bureaucrats" of the mid-nineteenth century. The bureaucratisation of the mining industry over the period 1835-1954 is described, and it is demonstrated that the industry obtained and now possesses those characteristics outlined by Max Weber in his model of bureaucracy. I analyse criticisms of the model and find them to be relevant, in that they facilitate understanding both of the circumstances of the accident and of the Inquiry . Further understanding of the circumstances and causes of the accident was gained by attendance at the lnquiry and by interviewing many of those involved in the Inquiry. I analyse many aspects of the Inquiry - its objectives. structure, procedure and conflicting interests - and find that, although the Inquiry had many of the symbols of bureaucracy, it suffered not from " too much" outside interference. but rather from the coal mining industry's shared belief in its ability to solve its own problems. I found nothing to suggest that, prior to the accident, colliery personnel relied. or were encouraged to rely, "too much" upon state regulation.

The fall and rise of tear albumin levels:a multifactorial phenomenon

Albumin in tears is used as a diagnostic marker of ocular insult and inflammation, but whether its presence in tears is responsive or part of an adaptive reaction remains unresolved. A review of the literature on tear albumin concentration emphasizes that variables such as collection method, stimulus, assay technique, and disease state influence the quoted values to different extents. Influence of assay technique is negligible in comparison to variation in sampling conditions. Ocular disease increases albumin concentrations but not in a specific manner. The literature review also highlighted that little systematic research has been carried out on the daily cycle of tear albumin levels. In order to remedy this shortcoming, we investigated variations in tear albumin concentration during the waking day. The concentration of albumin in 400 tear samples collected from 13 subjects was assessed at 2-hourly intervals throughout the waking day. Highest daytime albumin concentrations were obtained within 10 minutes of waking, with a mean concentration of >50 ± 22 µg/ml. Albumin levels were at their lowest, but most consistent, 2-6 hours post-waking. This pattern was followed by a progressive increase in albumin concentration during the latter part of the day. Although individual subject-to-subject concentration differences were observed, this distinctive pattern of diurnal variation was found in all subjects. The results presented suggest a regulated, not random, pattern of variation within the period of study. © 2013 Elsevier Inc. All rights reserved.

The SEC’s retail investor 2.0: Interactive data and the rise of calculative accountability

The Securities and Exchange Commission (SEC) in the United States mandated a new digital reporting system for US companies in late 2008. The new generation of information provision has been dubbed by Chairman Cox, ‘interactive data’ (SEC, 2006a). Despite the promise of its name, we find that in the development of the project retail investors are invoked as calculative actors rather than engaged in dialogue. Similarly, the potential for the underlying technology to be applied in ways to encourage new forms of accountability appears to be forfeited in the interests of enrolling company filers. We theorise the activities of the SEC and in particular its chairman at the time, Christopher Cox, over a three year period, both prior to and following the ‘credit crisis’. We argue that individuals and institutions play a central role in advancing the socio-technical project that is constituted by interactive data. We adopt insights from ANT (Callon, 1986; Latour, 1987, 2005b) and governmentality (Miller, 2008; Miller and Rose, 2008) to show how regulators and the proponents of the technology have acted as spokespersons for the interactive data technology and the retail investor. We examine the way in which calculative accountability has been privileged in the SEC’s construction of the retail investor as concerned with atomised, quantitative data (Kamuf, 2007; Roberts, 2009; Tsoukas, 1997). We find that the possibilities for the democratising effects of digital information on the Internet has not been realised in the interactive data project and that it contains risks for the very investors the SEC claims to seek to protect.

Singapore's online retail deviants:analyzing the rise of blogshops' power

Geography, retailing, and power are institutionally bound up together. Within these, the authors situate their research in Clegg's work on power. Online shopping offers a growing challenge to the apparent hegemony of traditional physical retail stores' format. While novel e-formats appear regularly, blogshops in Singapore are enjoying astonishing success that has taken the large retailers by surprise. Even though there are well-developed theoretical frameworks for understanding the role of institutional entrepreneurs and other major stakeholders in bringing about change and innovation, much less attention has been paid to the role of unorganized, nonstrategic actors-such as blogshops-in catalyzing retail change. The authors explore how blogshops are perceived by consumers and how they challenge the power of other shopping formats. They use Principal Components Analysis to analyze results from a survey of 349 blogshops users. While the results show that blogshops stay true to traditional online shopping attributes, deviations occur on the concept of value. Furthermore, consumer power is counter intuitively found to be strongly present in the areas related to cultural ties, excitement, and search for individualist novelty (as opposed to mass-production), thereby encouraging researchers to think critically about emerging power behavior in media practices.

The rise and fall of diasporic bonds in Japanese-Peruvian “Return” migration

Two decades after Japanese-Peruvians and other South Americans of Japanese descent began to migrate back to Japan, the return-migration phenomenon has ended. Induced by the Japanese government in the name of shared ethnicity, Japanese policymakers now largely regard return migration as a failed policy. It failed because return-migrants did not, in the view of policy- makers, assimilate, integrate, or “make it” in Japan as expected. Thus, once-imagined ethnic bonds ceased to exist in Japan. However, ethnic bonds sustained themselves well outside Japan. The Japanese-Peruvian community in Peru has thrived and maintained continuous ties with Japan. What explains the rise and fall of diasporic ethnic bonds? Drawing on my ethnographic research in Japanese-Peruvian communities in Peru and Japan, I found that diasporic ethnic bonds are cultivated or weakened depending upon where diasporic populations are located in relation to their ancestral homeland, and how such ties are utilized, for what, and by whom.

The rise and fall of stand-alone social reporting in a multinational subsidiary in Bangladesh:a case study

Purpose -The main aim of this paper is to examine the underlying drivers for the development and subsequent discontinuation of stand-alone corporate social responsibility (CSR) reporting in a multinational subsidiary in Bangladesh. Design/Methodology/Approach - The research approach employed for this purpose is a case study using evidence from a series of in depth interviews conducted during the period 2002-2010. Interview data is supplemented by examining other sources of information including annual reports, stand-alone social reports and relevant newspaper articles during the study period. Findings - It appears that the stand-alone CSR reporting process was initiated to give the subsidiary a formal space in which to legitimise its activities in Bangladesh where both tobacco control regulation and a strong anti-tobacco movement were gaining momentum. At the start of the process in 2002 corporate interviewees were very receptive of this initiative and strongly believed that it would not be a one off exercise. However, in the face of subsequent significant national policy shifts concerning tobacco control, irreconcilable stakeholder demands and increasing criticism of the CSR activities of the organisation at home and abroad the process was brought to an abrupt end in 2009. Research Limitations/Implications - The paper has a number of implications for policy makers concerning the future prospects for stand-alone social/sustainability reporting as a means of enhancing organisational transparency and accountability. In addition the paper discusses a number of theoretical implications for the development of legitimacy theory. Originality/value - Using the lens of legitimacy the paper theorises the circumstances leading to the initiation and subsequent cessation of CSR reporting in the organisation concerned. As far as we know this is the first study which theorises and provides significant fieldwork based empirical evidence regarding the discontinuation of stand-alone social reporting by a multinational company operating in a developing country. Thus, it extends previous desk-based attempts at using legitimacy theory to explain a decrease (or discontinuity) in CSR disclosures by de Villiers and van Staden (2006) and Tilling and Tilt (2010).

Higher-order aberrations in amblyopia:an analysis of pre- and post-wavefront-guided laser refractive correction

For more than a century it has been known that the eye is not a perfect optical system, but rather a system that suffers from aberrations beyond conventional prescriptive descriptions of defocus and astigmatism. Whereas traditional refraction attempts to describe the error of the eye with only two parameters, namely sphere and cylinder, measurements of wavefront aberrations depict the optical error with many more parameters. What remains questionable is the impact these additional parameters have on visual function. Some authors have argued that higher-order aberrations have a considerable effect on visual function and in certain cases this effect is significant enough to induce amblyopia. This has been referred to as ‘higher-order aberration-associated amblyopia’. In such cases, correction of higher-order aberrations would not restore visual function. Others have reported that patients with binocular asymmetric aberrations display an associated unilateral decrease in visual acuity and, if the decline in acuity results from the aberrations alone, such subjects may have been erroneously diagnosed as amblyopes. In these cases, correction of higher-order aberrations would restore visual function. This refractive entity has been termed ‘aberropia’. In order to investigate these hypotheses, the distribution of higher-order aberrations in strabismic, anisometropic and idiopathic amblyopes, and in a group of visual normals, was analysed both before and after wavefront-guided laser refractive correction. The results show: (i) there is no significant asymmetry in higher-order aberrations between amblyopic and fixing eyes prior to laser refractive treatment; (ii) the mean magnitude of higher-order aberrations is similar within the amblyopic and visually normal populations; (iii) a significant improvement in visual acuity can be realised for adult amblyopic patients utilising wavefront-guided laser refractive surgery and a modest increase in contrast sensitivity was observed for the amblyopic eye of anisometropes following treatment (iv) an overall trend towards increased higher-order aberrations following wavefront-guided laser refractive treatment was observed for both visually normal and amblyopic eyes. In conclusion, while the data do not provide any direct evidence for the concepts of either ‘aberropia’ or ‘higher-order aberration-associated amblyopia’, it is clear that gains in visual acuity and contrast sensitivity may be realised following laser refractive treatment of the amblyopic adult eye. Possible mechanisms by which these gains are realised are discussed.

The rise and fall of Germans in the British hospitality industry, c1880-1920

German migrants were to be found in significant numbers in the British hospitality industry during the period 1880 to 1920. They worked as waiters, chefs, and managers of restaurants and hotels. This article has three main sections. It begins with a brief outline of the rise of restaurants and hotels in late nineteenth-century Britain and the role of migrants in this process. It then analyses the Germans in the British hospitality industry in the decades leading up to the First World War. The article then focuses upon the rise of hostility towards Germans with the approach of the Great War, which led to dismissal, internment and repatriation during the conflict.