Tasting green leaf volatiles by larvae and adults of Colorado potato beetle,Leptinotarsa decemlineata.

Larvae and adults of the Colorado potato beetle,Leptinotarsa decemlineata (Say), are shown to have galeal gustatory cells that are highly sensitive to distillate of potato leaf extracts, (E)-2-hexen-1-ol, (E)-2-hexenal, and other saturated and unsaturated six-carbon alcohols. In larvae and adults, the sensory response patterns elicited by leaf homogenate, leaf distillate and a mixture of these two extracts differ in subtle ways. Beetle larvae feed most readily on Millipore disks treated with leaf homogenate and the mixture, but they did not feed on disks treated with leaf distillate. The differences in behavioral response and sensory input are used to derive a potential gustatory code that may stimulate different levels of feeding. This code may be disrupted by compounds present in nonhost leaves, thus leading to reduced feeding. Possible interactions of sapid leaf volatiles, amino acids, sugars, and potentially deterrent plant compounds are discussed.

The effect of admission to long-term care program on utilization of health services by the elderly in British Columbia.

Utilization patterns of elderly clients admitted to the British Columbia Long Term Care (LTC) program were recorded and analysed. Patients were either located at home or in facilities and were classified into one of five levels of care. Data on GP and specialist contacts, acute care hospital admissions and hospital length of stay were analysed for each client (N = 7251) for two consecutive years, one before and one after admission to the program. There was only a slight decline or no change in utilization of ambulatory health services following admission to the program but a more pronounced reduction in utilization of hospital related services particularly by clients located in facilities (60-70%). When utilization rates were controlled for peak levels in the period around admission, more moderate trends evolved. Yet, clients located in facilities showed a 20% decrease in hospital admission rates and a 40% decrease in GP hospital visits in the period following admission. The data suggests that admission to LTC may reduce acute hospital utilization and consequent physician utilization among clients who are cared for in an institution.

Dark Respiration during Photosynthesis in Wheat Leaf Slices.

The metabolism of [(14)C]succinate and acetate was examined in leaf slices of winter wheat (Triticum aestivum L. cv Frederick) in the dark and in the light (1000 micromoles per second per square meter photosynthetically active radiation). In the dark [1,4-(14)C]succinate was rapidly taken up and metabolized into other organic acids, amino acids, and CO(2). An accumulation of radioactivity in the tricarboxylic acid cycle intermediates after (14)CO(2) production became constant indicates that organic acid pools outside of the mitochondria were involved in the buildup of radioactivity. The continuous production of (14)CO(2) over 2 hours indicates that, in the dark, the tricarboxylic acid cycle was the major route for succinate metabolism with CO(2) as the chief end product. In the light, under conditions that supported photorespiration, succinate uptake was 80% of the dark rate and large amounts of the label entered the organic and amino acids. While carbon dioxide contained much less radioactivity than in the dark, other products such as sugars, starch, glycerate, glycine, and serine were much more heavily labeled than in darkness. The fact that the same tricarboxylic acid cycle intermediates became labeled in the light in addition to other products which can acquire label by carboxylation reactions indicates that the tricarboxylic acid cycle operated in the light and that CO(2) was being released from the mitochondria and efficiently refixed. The amount of radioactivity accumulating in carboxylation products in the light was about 80% of the (14)CO(2) release in the dark. This indicates that under these conditions, the tricarboxylic acid cycle in wheat leaf slices operates in the light at 80% of the rate occurring in the dark.

Forecasting client transitions in British Columbia's Long-Term Care Program.

This article presents a model for the annual transitions of clients through various home and facility placements in a long-term care program. The model, an application of Markov chain analysis, is developed, tested, and applied to over 9,000 clients (N = 9,483) in British Columbia's Long Term Care Program (LTC) over the period 1978-1983. Results show that the model gives accurate forecasts of the progress of groups of clients from state to state in the long-term care system from time of admission until eventual death. Statistical methods are used to test the modeling hypothesis that clients' year-over-year transitions occur in constant proportions from state to state within the long-term care system. Tests are carried out by examining actual year-over-year transitions of each year's new admission cohort (1978-1983). Various subsets of the available data are analyzed and, after accounting for clear differences among annual cohorts, the most acceptable model of the actual client transition data occurred when clients were separated into male and female groups, i.e., the transition behavior of each group is describable by a different Markov model. To validate the model, we develop model estimates for the numbers of existing clients in each state of the long-term care system for the period (1981-1983) for which actual data are available. When these estimates are compared with the actual data, total weighted absolute deviations do not exceed 10 percent of actuals. Finally, we use the properties of the Markov chain probability transition matrix and simulation methods to develop three-year forecasts with prediction intervals for the distribution of the existing total clients into each state of the system. The tests, forecasts, and Markov model supplemental information are contained in a mechanized procedure suitable for a microcomputer. The procedure provides a powerful, efficient tool for decision makers planning facilities and services in response to the needs of long-term care clients.

Placement changes in long-term care: three years' experience.

This paper describes the place and level of care of an urban and a semi-rural health unit for which 1,653 clients began their experience in British Columbia's Long-Term Care (LTC) program and where they were one and three years later. Three years after admission, 54 per cent of 759 clients initially admitted at home to the lowest level of care were still active clients: 25.8 per cent unchanged, 11.3 per cent at home but at a higher level of care, 16.9 per cent had moved to facilities, 25.4 per cent had died; the remainder of this group had been discharged from LTC. A similar proportion of the 184 clients admitted to the lowest level of care in facilities were still in the program at the end of three years. In contrast, 25 per cent of those admitted to the highest level of care at home (N = 60) and 14.1 per cent of those admitted to the highest level in facilities (N = 64) remained in the program after three years. The potential of the study data for planning purposes is suggested.

Acute-care hospitalizations and long-term care: an examination of transfers.

A Long-term Care Program was introduced throughout British Columbia, Canada, on January 1, 1978. This comprehensive community-based program emphasizes home care. A longitudinal study was started of all persons (N = 3518) admitted to the program that year in two health districts, one urban and one semirural. An examination of the relationship between acute-care hospitalization and long-term care (LTC) involved determining (1) the number of admissions (N = 364) to LTC directly from acute-care settings versus the number (N = 1287) entering directly from the community, (2) the number of LTC persons who were hospitalized at least once in the first 12 months after admission to LTC, and (3) the outcomes of these hospitalizations. Persons from the urban area who entered the LTC Program from an acute-care hospital were much more likely to be institutionalized than were those from the semirural area. In the LTC facility group, 388 persons (19.9 per cent) experienced at least one acute-care hospitalization during the first year of the program. More than 50 per cent of those transferred to an acute-care hospital for the first time returned to the same location and level of care afterward; 14 per cent died. These descriptive analyses may be of interest to health-care planners and to those who care for the LTC elderly either at home or in a facility.

Photosynthetic and Photorespiratory Characteristics of Mutants of Hordeum vulgare L.

The relationship between photosynthesis and photorespiration was determined in normal and 26 mutants of barley (Hordeum vulgare L. var. Himalaya). The rate of apparent photosynthesis ranged from 1 to 30 milligrams of CO(2) per square decimeter per hour. The variation in rate of photosynthesis was due, in some cases, to differences in chlorophyll content, in others to stomatal resistance, and in still others to unknown factors; but no single factor accounted for the variation. Photorespiratory activity, as determined by the (14)CO(2)/(12)CO(2) technique, CO(2) evolution into CO(2)-free air, and the response of photosynthesis to low and high O(2) concentrations, was positively and significantly correlated with photosynthesis. This supports the idea that the two processes are integrally and tightly coupled. There appears to be no competition between photosynthesis and photorespiration, and the probability of finding plants with high rates of photosynthesis and low rates of photorespiration measured under natural conditions, appears to be very low.