High Demand Situations Research Articles

The effects of increased protein intake on kidney size and function.

In endothermic vertebrates, long-term increases in metabolic energy demand are often associated with increases in food intake and accompanied by increases in organ mass. Wide-scale increases in organ mass have often been attributed to a metabolic response to increased energy intake and utilization. On a constant diet, however, increased food intake is also associated with increased protein intake. We hypothesized that, while increased food intake itself may be responsible for increases in digestive tract mass, the consequent increased protein intake would be the factor responsible for increased kidney mass and function. Thus, we exposed male and female mice to diets differing in protein level (7 %, 15 % or 46 % casein by mass) at different acclimation temperatures (5 degrees C or 23 degrees C). Within an acclimation temperature, food intake rate remained constant over the entire range of dietary protein level, and protein intake rate increased as dietary content increased. The mice in the cold-acclimation group increased food intake rate by 48-120 % over those in the warm-acclimation group. Liver, kidney and stomach mass increased with protein intake rate, while digestive tract and other vital organ masses increased only in response to increased energy intake rate. Blood urea nitrogen levels increased with protein intake rate. Glomerular filtration rates increased with increases in dietary protein level in male mice but not female mice. Finally nitrogen filtration rate increased with protein intake rate for mice on the high-protein diet. We suggest that it is primarily the increased protein intake rate rather than the increased food intake rate that results in the changes in kidney and liver mass and kidney function observed to occur in situations of high energy demand.

Low and high deviance analogue assessment of parent-training with physically abusive parents

This study examined the utility of a parent-training program which included training to facilitate generalization to high-demand child-management situations, and employed structured analogue assessments of parent discipline performance in high-demand situations. A single-subject design was used to evaluate the effects of intervention with three physically abusive parents. The use of parenting skills was observed during free-play assessments (in clinic and home) with their child and two home-simulation assessments (low- and highdeviance) with clinical assistants enacting scripted child behaviors. Results support the effectiveness of the parent-training package and the use of low- and high-demand home-simulation assessments. Attempts to assess the impact of treatment on child management related to high-demand situations is particularly important given that these situations may function as antecedents to abuse behavior. The findings contribute to the literature on parent-training withphysically abusive parents and suggest directions for future research and practice.

Cross-situational inconsistency in the behavior of compulsive and histrionic personality disorders: An analogue study

The purpose of this study was to examine empirically the personologist assumptions underlying definitions of personality disorders. The behavioral consistency or inconsistency of subjects with histrionic (n=28)or compulsive (n =26)personality disorder analogues, as well as control subjects (n=28)was investigated across situations that varied in type of audience (public vs. private) and type of demand (neutral vs. high), using three tasks. It was predicted from an interactionist perspective that histrionics would respond differently to private vs. public situations but consistently across the three tasks and that compulsives would respond differently to neutral-vs. high-demand situations but consistently across the three tasks. In contrast, the results were most consonant with a situationist perspective, with situational factors affecting all subject groups similarly, thus raising questions about personologist assumptions of personality disorders.

Stomatal conductance and transpiration of Acacia under field conditions: similarities and differences between leaves and phyllodes

Leaf diffusive conductance and transpiration rates in response to situations of high evaporative demand were measured in 40 Acacia species varying widely with regard to the morphological and anatomical characters of their assimilatory organs. The measurements took place in south-eastern and central Australia, central Africa and south-western Europe and included species of all three subgenera of Acacia Mill. Soil moisture conditions and consequently the water status of the experimental plants varied between the different measuring sites, some of which were regularly watered. All the species investigated showed a similar daily pattern of diffusive conductance with a morning peak and a subsequent decrease, which was more pronounced in plants growing under water stress, indicating a decisive stomatal regulation of transpiration. A relationship between the structure of assimilatory organs and leaf diffusive conductance or transpiration rates per unit surface area could not be detected in the Australian acacias. However, there are indications that the leaves of the non-Australian species operate on higher conductances than the foliage of the Australian ones. It is suggested that the observed differences in the performance of African and Australian acacias reflect the deciduous or evergreen nature of foliage rather than structural differences. In regard to taxon-specific differentiation this might implicate an ecophysiological character which separates the evergreen species of the geographically isolated subgenus Heterophyllum from the deciduous species of the subgenera Aculeiferum and Acacia with an overlapping area of distribution.

An Extended Traffic Flow Model for Inner Urban Freeways

Conventional macroscopic models for traffic flow in the past have shown a serious drawback when applied to inner urban freeways: traffic phenomena were not simulated realistically at high demand situations when traffic flow gets congested in front of a bottleneck or in the merging area of the numerous on-ramps. In this paper an extended macroscopic model is presented which overcomes these malfunctions by simple but effective modifications of the model equations. While the computational effort is increased only slightly, the model's performance is improved impressively when applied to urban freeways with many on- and off-ramps and bottlenecks. A verification of the model with real data from Santa Monica Freeway underlines the efficiency of the model's extensions.

The Contribution of Housing Displacement to the Decline of the Boarding and Lodging Population in Adelaide, 1947-77

This paper critically examines the assumption that the decline of boarding and lodging within the inner areas of large Australian cities is due principally to its displacement by 'gentrification'. A case study of the boarding and lodging sector shows that it has been affected by the same set of market and institutional pressures that have produced net losses in population and housing stock in the City of Adelaide. In addition, it appears that demand for boarding and lodging has been eroded by processes externalto the housing system. The readiness to attribute the decline of Adelaide's boarding and lodging accommodation purely to housing displacement has caused researchers to misjudge aspects of the restructuring of inner area population and housing resources, and led to misallocation. A GENERAL consensus is emerging in Australian urban studies that the large-scale reallocation of property in the inner areas of the nation's largest cities since the mid-196os has caused the extensive displacement of the most vulnerable housing groups in the community (Berry, 1977; Centre for Urban Research and Action, 1977; Department of Environment, Housing and Community Development, 1978; Kilmartin and Thorns, 1978; Sandercock, 1975). These groups mainly comprise poor residents-elderly pensioners, migrant and/or unskilled bluecollar workers and their families, and boarding house tenants-who have been relegated by the market to the city's cheapest housing, which is traditionally concentrated in inner areas. Most commentaries stress that the majority of these poor residents are the losers in a class struggle centring on the use of the inner city's housing stock, and that 'gentrification', a transitional process whereby the class composition of a residential neighbourhood changes from workingto middle-class, is the chief agent of displacement. Inner city areas over the last decade have been the focus of tremendous competition over land use which has caused the displacement of vulnerable housing classes . . . The concept of housing classes is particularly relevant to situations of market scarcity or high demand which have been characteristic of the inner suburban housing market in recent years. The demand shift towards inner suburban houses has produced new threats to the housing of certain housing classes, such as boarding house tenants and low income private tenants. These housing classes have incurred a great liability to the risk of housing displacement (Centre for Urban Research and Action, 1977, pp. 2-3). Interpretations of inner city change that stress competition and conflict between housing

Interactive Effects of Cognitive Involvement and Response Topography upon Differential Eyelid Conditioning to Conceptual Discriminanda

The purpose of the experiment was to determine some cognitive differences underlying the superior differential conditioning of voluntary-form (V) over conditioned-form (C) responders. Two cognitive activities were hypothesized to be jointly necessary for the superiority of Vs: first, an active development of reinforcement contingency awareness by the subject himself, and, second, an active use of acquired contingency knowledge in predicting UCS occurrences. The first variable was manipulated by asking half of the subjects to "figure out" the contingencies, while the other half were fully informed of them at the start. The second variable was assessed by requiring half of the subjects to engage in a button-pressing US prediction task on each trial. Conditioned discrimination indicated that, as predicted, both of these cognitive activities were required for good performance by Cs, supporting the hypothesis that Cs are normally deficient in these respects. An unpredicted deterioration in discrimination for Vs when both task manipulations were imposed suggested that competition between the Vs' spontaneous cognitive activities and the experimentally imposed ones developed in the high external demand situation.

Body temperature and the activity-stress ulcer in the rat

Rats which develop lesions after exposure to the activity-stress procedure show a drop in core body temperature. Body temperature and running activity are inversely related, thereby suggesting that excessive running is an attempt at behavioral thermoregulation. However, the restricted feeding schedule does not provide sufficient energy to support the high running activity. Rats placed in a cold environment (7°C) and fed only 1 hr daily also develop stomach lesions but not as extensive as rats housed in activity wheel cages and also fed 1 hr daily. These results suggest that the activity-stress procedure is a high energy demand situation and that subsequent stomach lesions represent a disturbance in energy metabolism.

Human Factors in Grain Harvesting Equipment Design

Agriculture is the third most hazardous industry in the United States, following mining and construction. Many agricultural hazards are related to the nature of agricultural machines and the conditions under which they are operated. Other hazards are the results of limitations of the human operator in relation to operational demands. Less than 5 percent of all U.S. workers were engaged in agriculture in 1974, but these accounted for 18.7 percent of all work related injuries. Farm machinery was involved in the greatest number of these accidents. Human factors engineering can be applied to agricultural safety through the analysis of man/machine/environment/task relationships. Defining topics for specific studies can be aided by analysis of agricultural accident surveys conducted by state and federal agencies. Some important differences exist between industrial and agricultural operations. These necessitate research techniques for agriculture differing from those used in industrial ergonomics. Isolation, self-reliance, self-management, and variability in conditions, operations and work schedules prevail in agriculture. A more thorough understanding of man-machine relationships is needed in studying the dynamics of field operations, especially when several pieces of equipment are being controlled by one operator. Routine service and maintenance operations are often hazardous in the way they are typically performed. A number of research frontiers exist in developing ways to study man-machine relationships under these conditions. In this paper, particular reference is made to the grain harvesting combine, a machine which in 1.4 million man-hours of exposure in 1974 produced an accident frequency rate of 112 per million hours. While the total percentage of agricultural worker time on combines was only 1.2, 6.4 percent of all farm machine accidents occurred while using them. Problems in using the combine are partially the result of its size, complexity, limited maneuverability, and the extended working hours over which it is often used. Field maintenance is frequently required and presents a variety of serious hazards. This paper includes discussion of ergonomic problems involved in the operation and maintenance of the combine. Concepts, proven useful in other operator center high-demand situations, appear to be useful in improving safety in this basic and important mechanized agricultural operation. Recent surveys and research suggest the development of improved analytic techniques as well as new applications of basic ergonomics in improving basic operator tasks. Some new developments and current problems in these areas are also presented.

Rotter's Generalized Expectancies as Predictors of Helping Behavior

96 college students were individually solicited for help, where the immediacy and the need for help were varied. They were then placed in a bystander intervention situation involving an emergency or a non-emergency. The Rotter and Levenson measures of internal control predicted helping, particularly in high demand situations. The data regarding Rotter's expectancies for interpersonal trust were inconsistent.

Infrared intensities as a quantitative measure of intramolecular interactions. Part XXXI. Intramolecular interactions in arylacetylenes

Integrated i.r. intensities of both the ν8 ring-stretching and ν(CC) bands of a series of m- and p-substituted phenylacetylenes indicate that the ethynyl group is a weak resonance donor when attached to a benzene ring. The group can become a strong resonance donor or acceptor in situations of high electron demand or excess, respectively.