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1584 Uppsatser om Light response - Sida 1 av 106

Evaluation of the retinal ON- and OFF-responses in the dog ERG

The aim of the study was to examine the retinal ON- and OFF-pathways of the canine electroretinogram (ERG). The ON- and OFF-pathways are used to distinguish objects from their backgrounds. A dark object is discernible from a lighter background using the OFFpathway and the ON-pathway is used to descry a light object upon a darker background. This study shows that the dog ERG has both ON- and OFF-responses and that these responses can be separated by prolonging the flash duration over 50 ms. The dog OFF-response waveform was more similar to the cat OFF-response than the human OFF-response (Frishman, 2006; Zrenner and Gouras, 1979). In this study six female three-year-old Beagle dogs were included. Both background and flash stimuli were provided by LEDs (light emitting diodes) with a wavelength of 470 nm, a wavelength that is absorbed almost as effectively by the canine M/L-cones as by the S-cones. These stimuli gave ERGs with both ON- and OFF-responses.

Lumilos

Lumilos is a work investigating the possibilities to use light and color in an interactive design context. I have explored different light sources and compared them to each other and given a short description of the history of light and how it has been developed during the industrialization in the western world. I have also investigated what is currently done in the field and summarized that with examples in the categories passive-, colored-, material- and interactive light. The conclusion is that working with interactive color and light is a hard task. There are many different angles to take into account such as personal likings and earlier experiences that is uncontrollable by the designer. Yet there are many possibilities and light is a material that is moldable in many forms. I have put the knowledge about light and color into practice and developed an interactive light wall that is visualizing energy consumption with the use of different colors of light and animations.

Cone. En armatur som bärs upp av sin egen ljuskägla.

Inspired by how to sketch a light cone from a flashlight in a comic I wanted to create an armature carried only by its own light cone. To manage this challenge I sketched in an architectural and sculptural way, where I chose to ignore the function of the lamp as long as possible.As a result I developed an armature with a stunning shape, with an illusion that it was carried by its own light cone. It could be hanged on a wall, placed on a table, pushed against a ceiling or standing on the floor.Depending of its size the light cone from the light source lightens up the surface and draws attention to the otherwise forgotten wallpaper or the undisposed statue in the darkness of the city..

Effect of low light intensities on dairy cows? behavior

The animal welfare act in Sweden states that dairy cows need to have at least a dim light present at night, but there are no recommendations for what intensity the light should have. It is unknown how cows perceive and react to low light intensities and earlier studies on this topic are limited. Red light as night light has also been suggested, based on the cows? inability to perceive red light. This have however been questioned. The aim with this study was to investigate how four different light intensities affect dairy cows behavior.

The cow eye-Function and effect of light on milk yield

The purpose of this review was to study the cow eye physiology, focusing on how it registers light, and to see how light affects the cow?s milk yield. It has been showed in studies that more hours of light per day (16 hours of light a day) as opposed to about 9-12 hours of light a day, increases milk yield for dairy cows. This review contains suggestions on how this is connected with the physiology of the eye. Vision is an important sense for many mammals, and is used to check out the animals surroundings. Sensor cells in the eyeball help in turning photons from the light into signals to the brain.

Svarstiden vid klinisk bedömning av högre språkliga förmågor hos vuxna

The aim of the present study was to investigate response time variations in tasks for assessment of high level language functions and how response time is related to education, age and gender. Response time is defined as the time to complete a task after it has been presented. 103 subjects, aged 20 to 80 years, were tested with the Assessment of Subtle Language Disorders, Sentence analysis and Morphological completion. The subtest Comprehension of ambiguous sentences showed the longest response time and Morphological completion the shortest. Correlations were found between increasing age and longer response time for Comprehension of metaphors and between education and response time for several subtests.

En jämförelse mellan ljus baserat i naturalism och pictorialism : En studie om ljussättning i spel

In this study, we investigate various lighting applications in a virtual environment, where we compare between light based in naturalism (natural light) and pictorialism (artistic light). The purpose of this study is to gain further knowledge in lighting, which is increasingly important for game graphics. Theory are examined to gather information and recommendations on how to use various light settings that convey different emotions. We then use this information to illuminate the environment that we have built. The environment is presented in Unreal 4 for respondents who are allowed to move around freely in the environment.

De norska grottmålningarna och ljuset

The relation between the cave and the circumpolar light conditions has long been a part of the interpretation of the meaning of the Norwegian cave art. This paper explores the relationship by trading the concept of a sensory dichotomy between light and darkness for that of a perceptual relationship between the paintings, the environment and the light..

En undersökning av ljus av ljus - den omvända skuggbildningen

This work is an exploration of a method and how to find balance between it and its contents. One part consists of a technical study on how to use UV light to yellow distinct surfaces on paper and the other is about how to find use of the method. The common denominator is determined as the consequence of the relationship between light and time. The result is three images that shows various traces of time with time as a graphic expression..

Incidenthantering i molnmiljö

Incident response plans are faced with new challenges as organisations expands to the cloud, this thesis aims to highlight these challenges and their potential solutions. Our work has focused on managing the incident response in contrast to earlier work that has been focusing on preventing them.As with any development, security is seldom prioritized. Instead the focus are often aimed towards usability and functionality, which means incident response plans are written, implemented, forgotten and finally becomes obsolete. This could result in an organization losing their ability to produce acceptable forensic images, avoid severe downtime, or prevent similar incidents in the future, which are all important parts of incident response.Traditional incident response plans does not address incidents in the cloud. Thus, an absence of guidelines for managing incidents in the cloud becomes apparent.

Effects of two different light programs on milk yield, prolactin, IGF-1 and sleep in dairy cows

The aim of this study was to investigate the relationship between sleep, photoperiod, milk yield and hormones connected to milk formation. Variations of prolactin (PRL) and Insulin-Like growth factor-1 (IGF-1) in plasma were measured during two different light programs. The light programs consisted of either 24 hours of light (L24:D0) or four hours of light and 20 hours of darkness (L4:D20). Five cows of the Swedish Red breed were used in a cross-over experiment and each light program consisted of five days. Milk yield was measured at every milking and milk samples were analyzed with regard to fat, lactose and protein.

Inkrementell responsanalys : Vilka kunder bör väljas vid riktad marknadsföring?

If customers respond differently to a campaign, it is worthwhile to find those customers who respond most positively and direct the campaign towards them. This can be done by using so called incremental response analysis where respondents from a campaign are compared with respondents from a control group. Customers with the highest increased response from the campaign will be selected and thus may increase the company?s return. Incremental response analysis is applied to the mobile operator Tres historical data.

"Bra jobbat!" : En undersökning av gymnasieelevers skriftliga kamratrespons

The chief aim of this study is to investigate the impact of context on written peer response. A second aim is to explore students? attitudes towards peer response. The investigation has taken place at an upper secondary school in the south-east of Sweden, involving 20 students in grade 2 and 3 in the course Swedish C. The investigation is based on the students? comments on their peers? speech drafts and six qualitative interviews.

Light pollution : consequences and sustainable lighting design

Light has always fascinated humans but ever since the invention of the first light bulb, the use of artificial lighting has accelerated dramatically. Darkness has never been as rare as today and the overuse of lighting has created a new phenomenon called light pollution. Most living beings are biologically dependent on the recurrent twenty-four-hour rhythm of light and darkness, called the circadian cycle. Human beings are evolutionary developed after this circadian rhythm and the effects of constant artificial light is yet unknown. Scientists fear the consequences of constant lighting and what it means physically, mentally and philosophically for the human species.

Jämförande studie av normal ERG-svar hos tre olika hundraser :

The purpose of this study was to compare normal electroretinographies (ERGs) from three different canine breeds in order to evaluate if there were any marked similarities or differences between these breeds as to ERG responses. It is known that healthy dogs from different breeds but also dogs within the same breed but in different age categories may have different appearances of their ERG responses. This may be a problem when evaluating if an ERG is normal or not from a dog within a breed not previously examined. Because of this it is important to obtain normal values for each breed and age group in order to be able to use these for later comparisons of ERGs obtained from individuals affected with various retinal diseases. In this study we have chosen to examine dogs within the three breeds: Labrador Retriever (LR), English Springer Spaniel (ESS) and Chinese Crested Dog (CCD). All of these breeds may be affected with hereditary retinal diseases such as Progressive Retinal Atrophy (PRA). It is possible that ERG-responses vary due to a number of different factors.

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