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Aim: To evaluate the short and medium term visual and refractive outcomes of a cohort of patients undergoing biometry-led sutureless extracapsular cataract extraction (ECCE) with implantation of posterior chamber intraocular lenses (PCIOL) in a rural African population. Methods: Cataract surgery was carried out on 96 eyes with PCIOL implantation according to biometry findings. After surgery, unaided visual acuity was assessed and objective and subjective refraction was assessed at discharge and again between 4 to 8 weeks follow-up in order to obtain the best-corrected visual acuity and report on surgically induced astigmatism. Results: 96 eyes of 68 patients were examined. 55 patients were excluded from the study because of lack of cooperation, the implantation of anterior chamber intraocular lenses or for other reasons (63.6% participation rate). The preoperative visual acuity was less than 3/60 in 43.8% of eyes, between 3/60 and 6/60 in 52.1% of eyes and 6/36 in 4.2% of eyes. The discharge refraction was taken 1 to 8 days and follow-up refraction was recorded 4 to 8 weeks after surgery. The unaided visual acuity at discharge was ≥6/18 in 45.3% of eyes and in 60.6% of eyes at follow-up. It was between 6/24 and 6/60 in 54.7% of eyes at discharge and 36.2% at follow-up. Unaided visual acuity <6/60 occurred in 3.2% of eyes at follow-up, whereas no poor outcomes (VA <6/60) were recorded at discharge. Best-corrected visual acuity of ≥6/18 was achieved in 78.5% of eyes at discharge and in 88.5% of eyes at followup. It was between 6/24 and 6/60 in 21.5% of eyes at discharge and in 9.6% of eyes at follow-up. Best-corrected visual acuity <6/60 only occurred in 2.1% of eyes at follow-up. The predicted post-operative spherical equivalents ranged from -0.76D to +0.29D (mean value: - 0.27D; SD: 0.19). The spherical equivalents found in refraction at discharge ranged from -3.25D to +2.88D (mean value: -0.88D; SD: 1.08) and at follow-ups from -2.50D to +2.25D (mean value: -0.58D; SD: 0.95). At discharge 3.2% of eyes were emmetropic, 79.8% were myopic and 17.0% were hyperopic. At follow-up 13.7% of eyes were emmetropic, 65.3% were myopic and 21.1% were hyperopic. Astigmatism was found in 70 eyes (74.5%) at discharge and in 57 eyes (60.0%) at follow-up. Conclusion: Sutureless ECCE with biometry-led selection of IOL is an effective and appropriate intervention for cataract blindness and visual impairment in rural Africa. Postoperative vision improves significantly at 1-2 month follow-up when compared to immediately post-op, although the small proportion of poor outcomes appears to increase in the same time period. Further research is needed to ascertain the longer term results of surgery, to focus on vision and induced astigmatism. It is also important to assess the patient’s subjective satisfaction with vision following sight restoring surgery.
Almost unlimited potential is seen in the offshore wind industry due to the exist-ence of stronger, steadier winds over the open sea and therefore it is expected to experience a remarkable growth. Wind power is one of the fastest-growing energy sources around the world and has great potential to offer clean and abundant ener-gy. Unlike onshore, where the landscape, trees and buildings distort the flow of the wind, there are no obstacles that influence the wind speed offshore, leading to a much more efficient energy generation potential.
On the other hand, unknown to the vast public, there are several technical, infra-structural, and financial challenges facing the offshore wind industry, such as the dependence on wind-speed, the complex installation and operation process of wind farms offshore, as well as the harsh marine conditions and other challenges which are caused by the fact that the offshore wind industry still is a relatively immature market.
In a world where customers are exposed to advertisement and marketing messages on a daily basis, traditional marketing has almost lost its power. Especially, younger persons simply don`t have the time or the patience anymore to listen to every single marketing message out there. This forces marketers to search for new ways to reach their customers. Nowadays they are not anymore focusing on ways to reach the customer directly but try to communicate their message indirectly via persons who are not necessarily involved in the marketing industry. Marketers define those persons as so-called influencers. Influencers can be individuals writing blogs or publishing articles in online forums as well as friends suggesting a special product they recently bought. After addressing basic topics like influencer marketing, the social web and the customer journey, I will head on with the main part of the thesis focusing on the different influencer categories and the methods for companies or brands to identify and control these influencers in a social web environment. The Web 2.0 has made this process a lot easier for companies since they are now able to use services like social influence scoring platforms to do so. An in-depth analysis of the algorithms and measurement processes used by those platforms will show the pros and cons of this method. Finally I will point out which influencer types would be helpful in each stage of the customer journey to generate sales as well as external elements capable of altering the influencer`s marketing message.
Purpose: Usually, a theory of attention upon gazed-at locations is applied. More parameters than gaze location can be derived to improve the theory of attention allocation. The aim of this study was to identify parameters related to eye tracking, that are suitable indicators of attention.
Methods: Binocular eye tracking data was collected with the Eye Tribe tracking system (The Eye Tribe Aps, Copenhagen, Denmark) for the task of visual exploration of the painting “Unexpected Visitors” by Ilya Repin. 20 subjects (valid data: 19/20) had to look at this painting for about two and a half minutes in order to generate fatigue and inattention. In a second step, suitable parameters of attention were transferred to a data set (8 subjects, valid data: 6/8) on a perimetric task executed with the OCTOPUS 900 perimeter (Haag-Streit, Köniz, Switzerland). Monocular parameters could be applied on the perimetric task, the error rate (false positive and false negative catch trials, 5 % each) were taken as additional parameter.
Results: For the image viewing task, the only parameter showing significance was the average level (a10) of fatigue waves (p = 0.00024, ANOVA, ∆ = -0.8316 px). Blink duration (∆ =-270.4 ms), pupil variability (∆ = -0.17868), saccade length (∆ =-0.3135 px) and fixation duration (∆ = 186.5 ms) did not change significantly, but showed relevant trends by differences ∆ of their median between the first and last tenth of the recording time. Blink rate and the Index of Cognitive Activity (ICA) did neither show significant changes nor relevant trends. Vergence accuracy failed to indicate fatigue due to variability between subjects and comparatively small effect size. For the perimetric data, in 3 of 6 subjects fatigue waves over a limited time window could be observed. Only for one subject, a relevant increase in false negative responses to catch trials (50 percentage points) could be observed.
Conclusion: Pupil diameter variability, saccade length, fixation duration and fatigue waves were the parameters indicating fatigue. Only the latter parameter has the potential to be applied to perimetric data.
Microflows: Leveraging Process Mining and an Automated Constraint Recommender for Microflow Modeling
(2018)
VR-EA: Virtual Reality Visualization of Enterprise Architecture Models with ArchiMate and BPMN
(2019)
The digital transformation occurring throughout enterprises results in an increasingly dynamic and complex IT landscape. As the structures with which enterprise architecture (EA) deals become more digital, larger, complex, and dynamic, new approaches for modeling, documenting, and conveying EA structural and relational aspects are needed. The potential for virtual reality (VR) to address upcoming EA modeling challenges has as yet been insufficient- ly explored. This paper contributes a VR hypermodel solution concept for visu- alizing, navigating, interacting with ArchiMate and Business Process Modeling Notation (BPMN) models in VR. An implementation demonstrates its feasibil- ity and a case study is used to show its potential.