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Strategy development is one of the crucial factors for a firm's performance. For it
to be developed, a strategic analysis has to be conducted first. It enables
companies to gain a deeper understanding of their internal and external
environment. In the present work, the specialty coffee market is closely analyzed through a strategic analysis. The focus of this study is the young company Tikuna, a coffee producer that aims to enter the German market. In this context, Tikuna's possible entry into the German market and the companies competitive capacities are analyzed. In order to implement the different tools of the analysis, extensive literature research, as well as one expert interview and a survey were conducted.
It was found that Tikuna possesses all characteristics to enter the German
market. However, due to the lack of a differentiation factor in Tikuna's value
proposition, its competitive capacity is limited to a short period of time. In this
sense, different recommendations are given in order to ensure long term success
in the market. The central one being that Tikuna has to use its main strength and
bring innovation to the market.
Aim Patrick J. Caroline and Mark P. Andre first reported about soft lens orthokeratology in 2005. In a number of articles in the past five years, they reported about their research on this topic and their new findings. The aim of this study was to continue the research of Patrick J. Caroline and Mark P. Andre and to collect more information about the outcome of the technique. Methods Ten subjects with low myopia from -0.25 D to -1.25 D and a refractive astigmatism from plano to -0.75 D were fitted with a -10.00 D CIBA VISION AIR OPTIX® NIGHT&DAY® silicone hydrogel contact lens and were told to wear the lenses over night and everted. Corneal topography and refraction measurements were taken after one night, one week and one month of contact lens wear. Results Eight out of ten subjects finished the study, six female and two male. The mean age of the subjects was 23.9 years. With the eight subjects who finished the study, the mean change in subjective refraction was about +1.00 D in the sphere and +0.22 D in the cylinder, with maximum changes of +1.75 D sphere and +0.75 D cylinder. The mean apical power change, measured with the topographer, was 1.11 D. Changes in K - readings ranged from slight corneal steepening in both of the meridians to 0.23 mm of corneal flattening in the horizontal meridian and 0.27 mm of corneal flattening in the vertical meridian. Corneal eccentricity decreased about 0.65 on average. The main complaints and problems were the high minus power and the decentration of the contact lens and the occurrence of ghosting at night. Conclusion The results of this study show that everted wear of a high minus silicone hydrogel contact lens can lead to orthokeratology - such as changes in corneal topography and subjective refraction. These changes range from plano to +1.75 D sphere and +0.25 D to +0.75 D cylinder but are unpredictable and vary from subject to subject. Additional studies regarding the contact lens decentration and the unpredictability of the outcome need to be done to optimize the process.
Purpose: The purpose of this thesis is to provide a comprehensive literature review about albinism as an inherited metabolic disorder of melanin synthesis along with those related conditions impacting the visual system. As such, it addresses eye care emphasizing the visual consequences of albinism along with diagnostic and treatment options.
Methods: Background knowledge about ocular development is given as well as information about etiological biochemical and genetic processes. The current classification, clinical findings and their assessment and management options are presented based on recent results of research. In conclusion, two case reports are described as examples of visual care options.
Results: Melanin plays a big role in the retinal and chiasmal development. Melanin biosynthesis can be disrupted by different genes in various ways which leads to the current classification of albinism. Clinical findings include fundus hypopigmenta-tion, nystagmus, iris transillumination, photophobia, foveal hypoplasia, excessive chiasmal decussation, reduced visual acuity, high astigmatism (with-the-rule), strabismus and decreased stereopsis. Treatment options to improve visual acuity, fixation and binocularity are (tinted) prescription lenses and contact lenses, low vision aids, surgical procedures and vision therapy. Medication and supplementa-tion for increased pigmentation are currently being tested on mice.
Conclusions: Albinism is caused by genetic mutations resulting in ocular and cutaneous hypopigmentation. It establishes various phenotypes that require different therapy approaches in order to improve vision and therefore quality of life.
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
To determine the stereo threshold and inherent variability with a monitor-based two-rod test at various eccentricities of the visual field. Additionally, to evaluate the duration of this procedure.
Subjects and methods
A pilot trial was conducted in five ophthalmologically normal subjects (2 male and 3 female) aged 21 – 23 years. Two black rods on white background, which appeared under an angle of 1° were presented in a viewing distance of 5.0 meters. The right rod was stationary, whilst the left rod appeared under a stereoscopic parallax, with an either proximal or distal displacement to the image plane. Threshold determination was assessed at seven eccentricities of the visual field by a staircase method. Eccentricities were 0° centrally, 5° to the right and left, 10° to the right and left and 15° to the right and left of the visual field. Proximal and distal displacement as well as the sequence of eccentricities were presented in random order. Stereo acuity was measured in two different sessions for four subjects and in five different sessions for one subject. For all sessions the duration was recorded. All sessions were separated by a time interval of at least 24 hours and no longer than 7 days. Evaluation was made by Wilcoxon test and Kruskal Wallis test at the 95% confidence level (CI) and the median was assessed for all thresholds.
Results
Stereo acuity declines with increasing eccentricities of the retina similar to visual acuity. While at 0° eccentricity thresholds were found to be lowest with (median) 5.0 seconds of arc (‘’) and the CI (0.5’’, 30.5’’) for all measurements, they increased to 112.2’’ at 15° eccentricity to the left in proximal displacement. Distal it was 19.9’’ centrally and 112.2’’ to the right at 15° eccentricity with CI (0.5’’, 30.5’’) for all measurements.
Repeatability of the threshold determination was found to be best at 0° eccentricity with proximal displacement showing the exact same result in the repetitive session and poorest repetition was found at 15° eccentricity to the left with distal displacement. Distal repeatability was worse than proximal. Median and CI of duration time was 5.3 (3.2, 8.3) minutes.
Conclusion
Stereo acuity thresholds are repeatable however increase with increasing eccentricity. Repetitions of the threshold determination do not vary considerably. The duration of these measurements indicates the monitor-based two-rod test as a fast procedure, that can be applied in future studies. The test program is limited by an imperfect algorithm and the stereoscopic images evoke cues, this should be reworked.
Ophthalmic lenses are ideally measured in accordance with the center of rotation of the eye. Therefore a measuring device was constructed due to this principle to measure lenses with a focimeter. In this work that measuring device was validated. Lenses of ± 4 dpt in spherical and aspherical design were measured across a field of 9x9 measuring points being at 5° distance from each other. This corresponds to a field of view of 40°. The measurement points in x- and y- direction were theoretically calculated to validate the measurement results. Regarding angles of incidence up to 20° it was supposed that the main optical aberration depends on a change in the sagittal and tangential sphere powers which is also defined as astigmatism. Therefore the calculation presents the tangential and sagittal oblique sphere powers depending on the different angles of the line of vision. On average the measurement results and the calculated data of the spherical designed lenses coincide quite good (correlation at 0,98), the systematic deviation of both values on average is 0.01 dpt and the random error (standard deviation) amounts 0.03 dpt on average. The minimum deviation is -0.06 dpt and the maximum is 0.09 dpt. Common focimeters have a measuring inaccuracy of up to 0.06 dpt (Diepes, Blendowske 2002). Therefore the quality of the measured data should be reliable. The aspherical designed lenses were compared to the spherical designed lenses. With increased angles of incidence the astigmatism of the aspherical lenses leads to lower values than the astigmatism of the spherical lenses
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.
This paper deals with the question of which factors have to be given for
successful share repurchases that create long-term shareholder value. Center of
the thesis is the agency theory and its influence on share repurchases. Based on
theoretical findings success factors for share repurchases are derived and then
verified by case studies.
The main drivers for a successful share repurchase elaborated by this paper are a
suitable long-term executive compensation, an independent board of directors and
a shareholder structure without a majority shareholder. Additionally the findings
show that tying repurchases to certain share price thresholds improves the quality
of share repurchases.
Feedback management in hearing aids and its challenges have been there for over 60 years. The basic principles of feedback management are still in use to prevent the hearing aids from oscillation. This work focusses on the feedback management in custom style hearing aids by comparing four different Invisible-In-the-Canal (IIC) hearing aids. Four test set-ups were created to find valid and reli-able methods and set-ups to test custom hearing aids for their feedback management. The goal was to find out if they could provide 1) stable gain, 2) good sound quality, 3) indicate specific frequencies audible feedback occurs and 4) to test the clinical robustness through subjective experience rating. The principle was: matched gain – matched acoustics.