title: Rheology of the gel formed in the California Mastitis Test

authors: Verbeek, Casparus Johan R.

subjects: Capillary viscosity

abstract: The California Mastitis Test has previously been adapted for use in an inline, cow-side sensor and relies on the fact that the viscosity of the gel formed during the test is proportional to the somatic cell concentration. In this paper, the use of capillary and rotational viscometry was compared in light of the expected rheology of the gel formed during the test. It was found that the gel is non-Newtonian, but the initial phase of viscosity increase was not due to shear dependence, but rather due to the gelation reaction. The maximum apparent viscosity of the gel was shear dependent while the time it took to reach the maximum was not truly shear dependent, but was rather dependent on the degree of mixing during gelation. This was confirmed by introducing a delay time prior to viscosity measurement, in both capillary and rotational viscometry. It was found that by mixing the reagent and infected milk, then delaying viscosity measurement for 30 s, shortened the time it took to reach maximum viscosity by more than 60 s. The maximum apparent viscosity, however, was unaffected. It was found that capillary viscometry worked well to correlate relative viscosity with somatic cell count, but that it was sensitive to the reagent concentration. It can therefore be deduced that the rheology of the gel is complicated not only by it being non-Newtonian, but also by the strong dependence on test conditions. These make designing a successful sensor much more challenging.

text: Rheology of the gel formed in the California Mastitis Test The California Mastitis Test has previously been adapted for use in an inline, cow-side sensor and relies on the fact that the viscosity of the gel formed during the test is proportional to the somatic cell concentration. In this paper, the use of capillary and rotational viscometry was compared in light of the expected rheology of the gel formed during the test. It was found that the gel is non-Newtonian, but the initial phase of viscosity increase was not due to shear dependence, but rather due to the gelation reaction. The maximum apparent viscosity of the gel was shear dependent while the time it took to reach the maximum was not truly shear dependent, but was rather dependent on the degree of mixing during gelation. This was confirmed by introducing a delay time prior to viscosity measurement, in both capillary and rotational viscometry. It was found that by mixing the reagent and infected milk, then delaying viscosity measurement for 30 s, shortened the time it took to reach maximum viscosity by more than 60 s. The maximum apparent viscosity, however, was unaffected. It was found that capillary viscometry worked well to correlate relative viscosity with somatic cell count, but that it was sensitive to the reagent concentration. It can therefore be deduced that the rheology of the gel is complicated not only by it being non-Newtonian, but also by the strong dependence on test conditions. These make designing a successful sensor much more challenging.

year: 2008

title: Oil company annual report disclosure responses to the 2010 Gulf of Mexico oil spill

authors: Summerhays, Kimberley

subjects: environmental accounting

abstract: This paper analyses the annual report disclosures of the other six largest oil companies in reaction to the 2010 Gulf of Mexico oil spill. It focusses on changes in disclosures that can be ascribed to the oil spill. The companies all increased their environmental disclosures, with positive disclosures increasing most. It shows the use of an image enhancement disclosure strategy and a (partial) disclaiming of responsibility disclosure strategy, but do not find evidence consistent with a deflection of attention disclosure strategy, probably due to the high profile of the incident. It is found that BP’s strategy of repeating disclosures about remedial activities several times in different parts of the annual report ensures: an emphasis on the positive, that all stakeholders regardless of their area of focus are likely to notice this disclosure, an increase in the volume of environmental disclosure, and that less detail can be disclosed, reducing litigation-related risks.

text: Oil company annual report disclosure responses to the 2010 Gulf of Mexico oil spill This paper analyses the annual report disclosures of the other six largest oil companies in reaction to the 2010 Gulf of Mexico oil spill. It focusses on changes in disclosures that can be ascribed to the oil spill. The companies all increased their environmental disclosures, with positive disclosures increasing most. It shows the use of an image enhancement disclosure strategy and a (partial) disclaiming of responsibility disclosure strategy, but do not find evidence consistent with a deflection of attention disclosure strategy, probably due to the high profile of the incident. It is found that BP’s strategy of repeating disclosures about remedial activities several times in different parts of the annual report ensures: an emphasis on the positive, that all stakeholders regardless of their area of focus are likely to notice this disclosure, an increase in the volume of environmental disclosure, and that less detail can be disclosed, reducing litigation-related risks.

year: 2012

title: Data logging and performance analysis software for teachers of indigenous New Zealanders: early results

authors: Barbour, Robert H.

abstract: Technology, in the form of personal computers, is making inroads into everyday life in every part of every nation. It is frequently assumed that this is 'a good thing'. However, there is a need for the people in each cultural group in each nation to appropriate technology for themselves. Indigenous people, such as the Maori of New Zealand/Aotearoa, are in danger of losing their language because technology has a European face. Yet despite the fact that the Maori are currently experiencing a cultural renaissance, there are no commercially available products that are specifically designed for Maori-speaking people.

text: Data logging and performance analysis software for teachers of indigenous New Zealanders: early results Technology, in the form of personal computers, is making inroads into everyday life in every part of every nation. It is frequently assumed that this is 'a good thing'. However, there is a need for the people in each cultural group in each nation to appropriate technology for themselves. Indigenous people, such as the Maori of New Zealand/Aotearoa, are in danger of losing their language because technology has a European face. Yet despite the fact that the Maori are currently experiencing a cultural renaissance, there are no commercially available products that are specifically designed for Maori-speaking people.

year: 1992