Search

We describe a method to image dissolved oxygen (O2), in 2D at high spatial (< 50-100 µm) and temporal (< 10 s) resolution. The method employs O2 sensitive luminescent sensor foils (planar optodes) in combination with a specialized camera system for imaging luminescence lifetime in the frequency-domain. Planar optodes are prepared by dissolving the O2-sensitive indicator dye in a polymer and spreading the mixture on a solid support in a defined thickness via knife coating. After evaporation of the solvent, the planar optode is placed in close contact with the sample of interest - here demonstrated with the roots of the aquatic plant Littorella uniflora. The O2 concentration-dependent change in the luminescence lifetime of the indicator dye within the planar optode is imaged via the backside of the transparent carrier foil and aquarium wall using a special camera. This camera measures the luminescence lifetime (µs) via a shift in phase angle between a modulated excitation signal and emission signal. This method is superior to luminescence intensity imaging methods, as the signal is independent of the dye concentration or intensity of the excitation source, and solely relies on the luminescence decay time, which is an intrinsically referenced parameter. Consequently, an additional reference dye or other means of referencing are not needed. We demonstrate the use of the system for macroscopic O2 imaging of plant rhizospheres, but the camera system can also easily be coupled to a microscope.

© 2019 American Chemical Society. Luminescence lifetime based imaging is still the most reliable method for generating chemical images using chemical sensor technology. However, only few commercial systems are available that enable imaging lifetimes within the relevant nanosecond to microsecond range. In this technical note we compare the performance of an older time-domain (TD) based camera system with a frequency-domain (FD) based camera system regarding their measuring characteristics and applicability for O 2 and pH imaging in environmental samples and with different indicator dye systems emitting in the visible and near-infrared part of the spectrum. We conclude that the newly introduced FD imaging system delivers comparable if not better results than its predecessor, now enabling robust and simple chemical imaging based on FD luminescence lifetime measurements.

Angiosperms, http://name.umdl.umich.edu/IC-HERB00IC-X-1533088%5DMICH-V-1533088, https://quod.lib.umich.edu/cgi/i/image/api/thumb/herb00ic/1533088/MICH-V-1533088/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. Some materials may be protected by copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, please contact the Herbarium professional staff: herb-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu., https://www.lib.umich.edu/about-us/policies/copyright-policy

Few data exist on respiratory effects of indoor air quality and comfort parameters in the elderly. In the context of the GERIE study, we investigated for the first time the relationships of these factors to respiratory morbidity among elderly people permanently living in nursing homes in seven European countries. 600 elderly people from 50 nursing homes underwent a medical examination and completed a standardised questionnaire. Air quality and comfort parameters were objectively assessed in situ in the nursing home. Mean concentrations of air pollutants did not exceed the existing standards. Forced expiratory volume in 1 s/forced vital capacity ratio was highly significantly related to elevated levels of particles with a 50% cut-off aerodynamic diameter of <0.1 µm (PM0.1) (adjusted OR 8.16, 95% CI 2.24–29.3) and nitrogen dioxide (aOR 3.74, 95% CI 1.06–13.1). Excess risks for usual breathlessness and cough were found with elevated PM10 (aOR 1.53 (95% CI 1.15–2.07) and aOR 1.73 (95% CI 1.17–10.3), respectively) and nitrogen dioxide (aOR 1.58 (95% CI 1.15–2.20) and aOR 1.56 (95% CI 1.03–2.41), respectively). Excess risks for wheeze in the past year were found with PM0.1 (aOR 2.82, 95% CI 1.15–7.02) and for chronic obstructive pulmonary disease and exhaled carbon monoxide with formaldehyde (aOR 3.49 (95% CI 1.17–10.3) and aOR 1.25 (95% CI 1.02–1.55), respectively). Breathlessness and cough were associated with higher carbon dioxide. Relative humidity was inversely related to wheeze in the past year and usual cough. Elderly subjects aged ≥80 years were at higher risk. Pollutant effects were more pronounced in the case of poor ventilation. Even at low levels, indoor air quality affected respiratory health in elderly people permanently living in nursing homes, with frailty increasing with age. The effects were modulated by ventilation

The aim of this study was to investigate how overall health, participation in physical activities, self-esteem, and social and financial resources are related to life satisfaction among people aged 65 and older with reduced activities of daily living (ADL) capacity in 6 European countries. A subsample of the European Study of Adults' Well-Being (ESAW), consisting of 2,195 people with reduced ADL capacity from Sweden, the United Kingdom, the Netherlands, Luxembourg, Austria, and Italy, was included. The Older Americans' Resources Schedule (OARS), the Life Satisfaction Index Z, and the Self-Esteem Scale were used. In all national samples, overall health, self-esteem, and feeling worried, rather than ADL capacity, were significantly associated with life satisfaction. The findings indicate the importance of taking not only the reduction in functional capacity into account but also the individual's perception of health and self-esteem when outlining health care and nursing aimed at improving life satisfaction. The study thus suggests that personal rather than environmental factors are important for life satisfaction among people with reduced ADL capacity living in Europe.

Background and aims: A large, national, long-term, longitudinal, multi-purpose study has been launched in Sweden - the Swedish National study on Aging and Care (SNAC). The study involves four research centers collecting data in four different areas of Sweden. Methods: The study consists of two parts: the population part and the care and services part. In the population part, a large, representative panel of elders in different age cohorts is followed over time to record and describe the aging process from different aspects. In the care and services part, a systematic, longitudinal, individually-based collection of data is performed concerning provision of care and services together with functional ability, specific health care problems, and living conditions of the recipients living in the area. Resuits: The data collection in the population part of the SNAC is not yet completed. In the present article, some preliminary results are reported from the care and services part. These pertain to comparisons between the participating areas with respect to the prevalence of disability among those receiving care and social services in their ordinary homes and those receiving care in special accommodation. A comparison is also presented with regard to the amount of home help provided to subjects with a given disability. Conclusions: This project has several advantages. It is expected to generate a rich data base relevant for future research on aging and care and to have a direct impact on the future Swedish system of care and services for the elderly.

We describe two applications of a recently introduced system for very precise, continuous measurement of water oxygen saturation. Oxygen microoptodes (based on the dynamic fluorescence quenching principle) with a tip diameter of ~50µm, an 8-channel optode array, an intermittent flow system, and online data registration were used to perform two types of experiments. The metabolic activity of Antarctic invertebrates (sponges and scallops) was estimated in respiration experiments and, secondly, oxygen saturation inside living sponge tissue was determined in different flow regimes. Even in long-term experiments (several days) no drift was detectable in between calibrations. Data obtained were in excellent correspondence with control measurements performed with a modified Winkler method. Antarctic invertebrates in our study showed low oxygen consumption rates ranging from 0.03 - 0.19 cm3O2oh-1oind-1. Oxygen saturation inside living sponge specimens was affected by flow regime and culturing conditions of sponges. Our results suggest that oxygen optodes are a reliable tool for oxygen measurements beyond the methodological limits of traditional methods.