Predicting caregiver burden in general veterinary clients: Contribution of companion animal clinical signs and problem behaviors.

Caregiver burden, found in many clients with a chronically or terminally ill companion animal, has been linked to poorer psychosocial function in the client and greater utilization of non-billable veterinary services. To reduce client caregiver burden, its determinants must first be identified. This study examined if companion animal clinical signs and problem behaviors predict veterinary client burden within broader client- and patient-based risk factor models. Data were collected in two phases. Phase 1 included 238 companion animal owners, including those with a sick companion animal (n=119) and matched healthy controls (n=119) recruited online. Phase 2 was comprised of 602 small animal general veterinary hospital clients (n=95 with a sick dog or cat). Participants completed cross-sectional online assessments of caregiver burden, psychosocial resources (social support, active coping, self-mastery), and an item pool of companion animal clinical signs and problem behaviors. Several signs/behaviors correlated with burden, most prominently: weakness, appearing sad/depressed or anxious, appearing to have pain/discomfort, change in personality, frequent urination, and excessive sleeping/lethargy. Within patient-based risk factors, caregiver burden was predicted by frequency of the companion animal's signs/behaviors (P<.01). Within client-based factors, potentially modifiable factors of client reaction to the animal's signs/behaviors (P=.01), and client sense of control (P<.04) predicted burden. Understanding burden may enhance veterinarian-client communication, and is important due to potential downstream effects of client burden, such as higher workload for the veterinarian. Supporting the client's sense of control may help alleviate burden when amelioration of the companion animal's presentation is not feasible.

Gaseous templates in ant nests.

We apply a diffusion model to the atmosphere of ant nests. With particular reference to carbon dioxide (CO2), we explore analytically and numerically the spatial and temporal patterns of brood- or worker-produced gases in nests. The maximum concentration within a typical one-chamber ant nest with approximately 200 ants can reach 12.5 times atmospheric concentration, reaching 95% of equilibrium concentrations within 15 min. Maximum concentration increases with increasing number of ants in the nest (or production rate of the gas), distance between the centre of the nest ants and the nest entrance, entrance length, wall thickness, and with decreasing entrance width, wall permeability and diffusion coefficient. The nest can be divided into three qualitatively distinct regions according to the shape of the gradient: a plateau of high concentration in the back half of the nest; an intermediate region of increasingly steep gradient towards the entrance; and a steep linear gradient in the entrance tunnel. These regions are robust to changes in gas concentrations, but vary with changes in nest architecture. The pattern of diffusing gases contains information about position and orientation relative to gas sources and sinks, and about colony state, including colony size, activity state and aspects of nest architecture. We discuss how this diffusion pattern may act as a "dynamic template", providing local cues which trigger behavioural acts appropriate to colony needs, which in turn may feed back to changes in the gas template. In particular, wall building occurs along lines of similar concentration for a variety of nest geometries; there is surprising convergence between the period of cycles of synchronously active ants and the time taken for CO2 levels to equilibrate; and the qualitatively distinct regions of the "dynamic template" correspond to regions occupied by different groups of ants.

The Oxylog oxygen consumption meter: a portable device for measurement of energy expenditure.

The Oxylog (PK Morgan, Kent, UK) is a recently developed portable device for measurement of oxygen consumption and energy expenditure in man. It incorporates a turbine flowmeter and two polarographic oxygen sensors and is powered by rechargeable batteries. Two instruments were modified for operation at low ventilation rates and used in simultaneous Oxylog and Douglas Bag measurements of resting metabolic rate (RMR) in nine healthy subjects. The coefficients of correlation between RMR measured by the two methods were +0.904 (p less than 0.02) and +0.934 (p less than 0.01) and the standard errors of the mean percent error in energy expenditure were +/- 2.0% and +/- 2.7% for the two instruments respectively. This suggests that the Oxylogs are sufficiently accurate for many field studies of energy expenditure.

Metabolic rate and thyroid status in rats fed diets of different protein-energy value: the importance of free T3.

Oxygen consumption and thyroid hormone status have been investigated in relation to dietary protein and energy intake in young growing rats fed a control diet of 18% protein as well as diets containing 9 and 4.5% protein fed ad libitum and an 18% protein diet fed at a restricted intake for up to 14 days. Measurements of growth rate, food intake and oxygen consumption indicated that the rats fed a 4.5% protein diet ad libitum and those fed restricted amounts of an 18% protein diet have behaved similarly with severely arrested growth and reduced rates of oxygen consumption and food intake. However, the rats fed the 9% protein diet ad libitum differed from the control group only in terms of a reduced growth rate. Among all the rats thyroid hormone status was associated with the metabolic rate only in the case of the concentration of free L-3,3',5-triiodothyronine (T3), which was reduced in the groups fed 4.5% protein and 18% protein (restricted). Total T3 was actually increased in the rats fed 9% and 4.5% protein and unchanged in the restricted group. These differences in the concentrations of free and total T3 appeared to reflect the fact that the binding capacity for T3 increased with decreasing levels of dietary protein. It is concluded therefore that measurement of free rather than total T3 is the appropriate index of physiological thyroid status in protein-energy malnutrition, at least in the rat.

A multivariate analysis and modification of a preattentive, perceptual dysfunction in schizophrenia.

Preattentive information processing was examined in matched samples of process nonparanoid schizophrenics, reactive paranoid schizophrenics, and nonschizophrenic psychiatric inpatients. Three measures of visual preattentive processing were administered under standard conditions and also enriched conditions in which preattentive discriminability was enhanced through increased perceptual grouping and segregation. Nonparanoid schizophrenics displayed a differential performance deficit under standard conditions on each measure. Under conditions of enhanced preattentive discriminability, nonparanoid schizophrenics differentially improved to the extent that no significant differences were found between groups on two of the measures. Paranoid schizophrenics and psychiatric controls did not differ significantly across measures or conditions.