Showing papers by "University of Wollongong published in 1995"

How nation‐states respond to immigration and ethnic diversity

Abstract: Large scale migrations since 1945 have led to major changes in the ethnic composition of most highly‐developed countries. Nations have responded in a variety of ways, which have helped determine patterns of ethnic group formation. This article suggest a typology of policy models: the differential exclusion model, the assimilation model, and the pluralist model. Examples are discussed for each model. The models are then linked to different historical patterns of nation‐state formation. The differential exclusion model, which is based on the desire to prevent permanent settlement, has proved very hard to maintain because it leads to social tension and because it contradicts the democratic principle of including all members of civil society in the nation‐state. Countries applying the assimilation model have generally moved to a mixed approach, embodying some elements of the pluralist model. This has led to difficulties, because of contradictions between explicit goals and actual policies. Pluralist ...

A Typology of Service Firms in International Markets: An Empirical Investigation:

Abstract: Globalization of markets and competition has created unlimited opportunities for marketers of services internationally. Service providers, with a wide range of products ranging from professional se...

Association between heart rate variability and training response in sedentary middle-aged men

Abstract: The effect of exercise training on heart rate variability (HRV) and improvements in peak oxygen consumption (\(\dot V{\text{O}}_{\text{2}} \)peak) was examined in sedentary middle-aged men. The HRV and absolute and relative\(\dot V{\text{O}}_{\text{2}} \)peak of training (n = 19) and control (n = 15) subjects were assessed before and after a 24-session moderate intensity exercise training programme. Results indicated that with exercise training there was a significantly increased absolute and relative\(\dot V{\text{O}}_{\text{2}} \)peak (P 0.005) in the high HRV group (17% and 20% respectively) compared to the low HRV group (6% and 1% respectively). The groups did not differ in mean age, pretraining oxygen consumption, or resting heart rate. These results would seem to suggest that a short aerobic training programme does not alter HRV in middle-aged men. Individual differences in HRV, however, may be associated with\(\dot V{\text{O}}_{\text{2}} \)peak response to aerobic training.

Response of tide‐dominated mangrove shorelines in Northern Australia to anticipated sea‐level rise

Abstract: The exact response of mangrove shorelines to anticipated sea-level rise will depend upon the balance between sedimentation and sea-level change. Within the Top End of the Northern Territory of Australia there are extensive, relatively unmodified, tide-dominated mangrove forests, where tidal processes redistribute sediment. Harbours, such as Darwin Harbour, and tidal rivers, such as the South Alligator River with its associated coastal and estuarine plains, represent opposite extremes in terms of Holocene sedimentary infill, and will respond differently to sea-level rise. In Darwin Harbour, mangrove assemblages can be recognized in geomorphologically defined habitats. Similar topography within and between creeks implies morphodynamic equilibrium with tidal processes. Tidal reworking of sediment may maintain an equilibrial profile under gradually rising sea level, with resuspension of lower intertidal and subtidal muds and their redeposition within upper intertidal mangrove habitats. In contrast, the plains along the coast and tidal rivers draining into van Diemen Gulf developed during the post-glacial marine transgression, and since sea level stabilized, around 6000 years ago, coastal plains have prograded. These broad plains are presently not extensively influenced by salt water, but are often at elevations close to, or even below, modern high-tide levels. They may, therefore, revert to saline conditions particularly rapidly if the sea rises. The pattern of change may not be directly analogous to marine incursion experienced in the early Holocene, because broad plains have been able to prograde during the last 6000 years of relatively stable sea level.

Nitriding of austenitic stainless steel by plasma immersion ion implantation

Abstract: Plasma immersion ion implantation (PI3™), in which the diffusion of nitrogen from a low pressure r.f. plasma is combined with the implantation of nitrogen ions at energies up to 45 kV, is an effective means of nitriding austenitic stainless steel. At temperatures up to 450 °C, tribological properties can be improved without loss of corrosion resistance. In common with other nitriding processes in this temperature range, a supersaturated f.c.c. phase is formed, sometimes described as expanded austenite, which is maintained to very high nitrogen concentrations. At higher temperatures, chromium nitride is precipitated and the expanded austenite decomposes, leading to a reduction in corrosion resistance. Glancing-angle X-ray diffraction (XRD) of PI3-treated AISI 316 stainless steel at temperatures between 350 and 450 °C suggests that a highly homogeneous layer of expanded austenite is produced. The expansion increases with increasing process time, but decomposition of the supersaturated phase occurs after several hours of treatment if the temperature is too close to 450 °C. For a fixed process time, the expansion appears to be greatest at the lower temperatures (350 °C), although it can also be influenced by other processing parameters such as plasma density. Microstructural examination by cross-sectional transmission electron microscopy (TEM) has challenged the identification of the supersaturated phase as expanded austenite and reveals the complexity of the modified layer not seen by glancing-angle XRD. Most striking is the formation of a thick (2–3 μm) amorphous zone which may contain nanocrystalline precipitates of CrN and α-ferrite. A highly defective layer (up to 2 μm thick) of expanded austenite has been observed to underlie the amorphous zone where nitrogen diffusion is facilitated by the high defect density. Only partial reconciliation of the TEM results with the XRD observations has been possible to date.

Preferred Room Temperature of Young vs Aged Males: The Influence of Thermal Sensation, Thermal Comfort, and Affect

Abstract: BACKGROUND: While research has demonstrated that aged persons may show impaired thermoregulatory control, we do not know whether dysthermia in the aged results from altered behavioral or autonomic responses. Consequently, we investigated age-related differences concerning the ability to regulate room temperature. METHODS: Two groups of matched healthy males (22.9 yr and 66.9 yr) were subjects of this study. After equilibration at 24 degrees C (rh 50%), chamber temperature controllers were set into cooling mode. Using a dual position switch, subjects adjusted this temperature when air temperature moved outside their preferred range. Switch operation resulted in maximal cooling or heating, without a steady state. Subjective ratings of thermal sensation, discomfort, and affect were provided at each activation. RESULTS: Both groups controlled temperature equivalently: 24.9 degrees C (+/- 1.3, young) and 24.5 degrees C (+/- 1.5, elderly; p > .05). At cold-induced change points, the skin temperatures of the calf, thigh, chest, and hand were significantly lower in the elderly subjects. During the heat-induced changes, chest, hand, upper arm, and mean skin temperatures were also lower (p < .05). At cold-induced change points, the elderly group felt colder (p < .05), were less uncomfortable (p < .05), and felt better than the young subjects (p < .05). During heat-induced changes, thermal sensation was equivalent, the elderly were more comfortable (p < .05), and felt better (p < .05). CONCLUSIONS: Assuming thermal discomforture drives behavior, it is possible that elderly people may require a more intense thermal stimulus to elicit the appropriate behavioral responses in the home. It is also possible that such stimuli will result in a greater heat flow, elevating the risk of dysthermia in the aged.

Membrane fatty acid composition of tissues is related to body mass of mammals

Abstract: Phospholipids were extracted from tissues (heart, skeletal muscle, kidney cortex, liver and brain) of mammals representing a 9,000-fold range in body mass (mouse, rat, rabbit, sheep and cattle) and their fatty acid composition was determined. In heart, skeletal muscle and kidney cortex, there were significant allometric decreases in the Unsaturation Index (UI; average number of double bonds per 100 fatty acid molecules) with increasing body mass. There were significant inverse allometric relationships between body mass and the proportion of docosahexaenoic acid (22∶6ω3) in heart and skeletal muscle. In heart, skeletal muscle and kidney cortex, larger mammals also had shorter fatty acid chains in their phospholipids and a higher proportion of monounsaturates. In liver, smaller mammals had a higher UI than larger mammals (except the rabbit, which had the lowest UI and very low proportions of ω3 fatty acids). The brain of all mammals maintained a high UI with similar levels of polyunsaturated fatty acids, especially 22∶6ω3. Our results suggest that in heart, skeletal muscle and kidney cortex the activity of the elongases and desaturases are reduced in large mammals compared to small mammals. The allometric trends in membrane composition may be involved in modifying membrane permeability. It is proposed that the elevated degree of polyunsaturation in the membranes of several tissues from small mammals is related to their higher metabolic activity.

Effects of an intensive 12-wk training program by elite swimmers on neutrophil oxidative activity.

Abstract: The effects of an intensive 12-wk training program by 12 national-level swimmers on neutrophil oxidative activity were studied. Eleven sedentary (untrained) subjects (6 males and 5 females) served as environmental controls. Blood samples (10 ml) were taken at rest from an antecubital vein and neutrophils isolated by standard separation techniques. The oxidative burst activity of isolated neutrophils was assessed with an in vitro flow cytometric assay that used the fluorescent probe dihydrorhodamine 123. Two-way ANOVA (repeated measures) showed that oxidative activity was lower (P < 0.05) in the elite swimmers compared with the sedentary control group across the 12-wk period. Analysis of cells from swimmers in training was made: repeated measures ANOVA provided evidence of a significant decline (P < 0.05) in the number of cells responding positively ito in vitro challenge. Despite this decline, there was no significant difference in self-reported upper respiratory tract infection rate between the swimmers and sedentary individuals. These data show that: (i) elite swimmers undertaking intensive training have a significantly lower neutrophil oxidative activity at rest than do age- and sex-matched sedentary individuals; (ii) aspects of oxidative activity in swimmers are further suppressed during periods of strenuous training, and (iii) the extent of the suppression does not appear to be of clinical significance.

Relationship between body mass, tissue metabolic rate, and sodium pump activity in mammalian liver and kidney

Abstract: The allometric relationship between body mass and tissue metabolism was examined in liver and kidney cortex slices from mouse, rat, rabbit, sheep, and cattle, representing an approximately 12,000-fold difference in body mass and an 11-fold difference in mass-specific basal metabolic rate. Larger mammals have lower tissue metabolic rates (TMR; mumol O2.g wet wt-1.min-1) at 37 degrees C, yielding the equations TMR = 3.6 M-0.21 for liver slices and TMR = 3.2 M-0.11 for kidney cortex slices, where M is body mass in grams. This appears to be an intrinsic property of the tissue and is not due to differences in extracellular space or tissue protein content, because these are relatively constant in all mammalian species examined. The allometric relationships remain when tissue metabolism is expressed relative to "active cell mass" in tissue slices. Potassium uptake rate (KUR; mumol K+.g wet wt-1.min-1) was also measured (as 86Rb+ uptake) and was also lower in larger mammals, yielding the equations KUR = 1.2 M-0.14 in liver slices and KUR = 3.4 M-0.13 for kidney cortex slices. The energetic costs of sodium pump activity were estimated to be < 10% of TMR for liver and kidney cortex from all five mammalian species.

Redistribution of body fluids during postural manipulations

Abstract: Inter-compartmental body-fluid distribution is contingent upon posture, exercise state and environmental temperature. This investigation aimed at quantifying the distribution of intra- and extravascular fluid volumes during postural manipulations. Fluid shifts were measured in eight males utilizing a simultaneous, radionuclide dilution technique, in which radioiodinated serum fibrinogen, radiochromated erythrocytes, radiobromine and tritiated water were used to measure plasma, red cell, extracellular and total body water volumes. Subjects were exposed to three postural changes [seated (control), supine and standing] for 30 min at an air temperature of 22.0 degrees C, with each posture separated by 30 min seated rest. Total body water content remained stable throughout postural changes (P = 0.842). Relative to seated volumes, BV increased by 89 mL when supine, and decreased by 406 mL while standing (P = 0.003), with such shifts being primarily a result of plasma movement (P = 0.011). Red cell volume changes were not significant. Vascular fluid lost during standing was filtered into the interstitial compartment (P = 0.014), with the extracellular and intracellular volumes remaining unaffected. (P = 0.271 and P = 0.800, respectively). These observations confirmed the influence of posture on inter-compartmental body-fluid distribution. The intravascular fluid loss when standing was caused by the filtration of plasma into the interstitium, while, during supine rest, intravascular volume increased, reflecting fluid flux from the interstitium to the circulation.

The topography of eccrine sweating in humans during exercise

Abstract: The purpose of this study was to investigate the distribution of steady-state sweating rates (m sw), during stressful exercise and heat exposures. Six men completed 42-min trials: 2-min rest and 40-min cycling at 40% peak power in 36.6° C (relative humidity 46.0%). The m sw, was monitored using ventilated capsules at the forehead, and at three additional sites. Repeat trials allowed monitoring from eleven skin surfaces. Auditory canal temperature (Tac) and 11 skin temperatures were measured. After normalising m sw to the forehead response within subjects, differences in T ac and onset time thresholds, and transient and steady-state m sw were examined. The pooled, lower torso m sw onset [mean 45.5 (SEM 42.0) s] preceded that of the head [mean 126.5 (SEM 34.8) s, P<0.05], but was not significantly different from the legs [mean 66.6 (SEM 25.7) s], upper torso [mean 80.2 (SEM 36.8) s] or arms [mean 108.6 (SEM 31.2) s]. Transient m sw did not differ among regions (P=0.16). Mean, steady-state forehead m sw [3.20 (SEM 0.51) mg · cm−2 · min−1]was not significantly greater than the scapula, forearm, hand, stomach and lower back m sw (in descending order), but was greater than the chest [1.6 (SEM 0.2)], upperarm [1.6 (SEM 0.2)], calf [1.5 (SEM 0.3)] and thigh m sw [1.0 (SEM 0.2), P<0.05 for all comparisons]. The results did not support the caudal-to-rostral sweat onset evident during supine, resting heat stress. Equivalent T ac sweat thresholds existed between sites, while steady-state m sw topography varied among subjects and was not dominated by central regions.

Nonlinearity and propagation characteristics of balanced Boolean functions

Abstract: Three important criteria for cryptographically strong Boolean functions are balance, nonlinearity, and the propagation criterion. The main contributions of this paper are to reveal a number of interesting properties of balance and nonlinearity, and to study systematic methods for constructing Boolean functions that satisfy some or all of the three criteria. We show that concatenating, splitting, modifying, and multiplying (in the sense of Kronecker) sequences can yield balanced Boolean functions with a very high nonlinearity. In particular, we show that balanced Boolean functions obtained by modifying and multiplying sequences achieve a nonlinearity higher than that attainable by any previously known construction method. We also present methods for constructing balanced Boolean functions that are highly nonlinear and satisfy the strict avalanche criterion (SAC). Furthermore we present methods for constructing highly nonlinear balanced Boolean functions satisfying the propagation criterion with respect to all but one or three vectors. A technique is developed to transform the vectors where the propagation criterion is not satisfied in such a way that the functions constructed satisfy the propagation criterion of high degree while preserving the balance and nonlinearity of the functions. The algebraic degrees of functions constructed are also discussed.

An Empirical Investigation of Consumer Memory, Attitude, and Perceptions toward Pioneer and Follower Brands:

Abstract: The authors’ study provides the first survey-based approach for examining consumer cognitions, affect, and reported behavior toward pioneer brands. Prior consumer research on pioneers has largely f...

Pregnancy Outcomes in Women Without Gestational Diabetes Mellitus Related to the Maternal Glucose Level: Is there a continuum of risk?

Abstract: OBJECTIVE To examine selected pregnancy outcomes in women without gestational diabetes mellitus to see whether there was a continuum of risk related to the maternal glucose level. RESEARCH DESIGN AND METHODS Consecutive women attending two prenatal clinics and three obstetricians in private practice were tested for GDM at the beginning of the third trimester using a 75-g glucose load in the fasting state. The rate of induction, the number of assisted deliveries, the presence of pregnancy-induced hypertension, fetal birth weights, and morbidity were examined with respect to the maternal 2-h glucose level. RESULTS Data were available for 1,441 women with a 2-h glucose level CONCLUSIONS In normal women there is a continuum of risk related to the maternal glucose level 2 h after a glucose tolerance test for the probability of having an assisted delivery and the likelihood of the baby being admitted to an SCN. The chance of having pregnancy-induced hypertension or a LGA baby also increased as the maternal glucose level increased but could be largely explained by an increasing body mass index.

Effect of work station design on sitting posture in young children

Abstract: The purpose of the study was to compare muscular activity levels and sitting posture displayed by 10 children (mean age = 4.7 years) when performing tracing tasks while seated at a traditional work station (level desk top, 5 degrees backward sloping seat) and at an ergonomically designed work station (15 degrees sloping desk top, 15 degrees forward sloping seat). EMG profiles of latissimus dorsi (LD), erector spine (ES), and superior trapezius (ST) were sampled using Medi-trace disposable surface electrodes for 10 min on the non-dominant side. Muscle activity was sampled (1000 Hz) every 2 min for 5000 ms while the subjects performed the tracing tasks at each station. Raw EMG signals of the five trials for each muscle were processed by removing signal offset, full-wave rectification, and integration. The subjects' posture was monitored from a lateral view using a Panasonic VHS video camera while the children were seated at each work station. Neck flexion angle and the angle between the torso and thigh (hip angle) were manually sampled from the video images each 1 min as an indication of the posture adopted by the subjects during the tracing tasks. Use of t-tests for dependent means indicated that there was no significant difference in either mean ES or ST muscle activity as a function of work station design. However, subjects demonstrated significantly less LD activity when seated at the ergonomic work station (mean = 20.9 V ms) compared with the traditional work station (mean = 24.4 V ms, t = -2.88, p = 0.018).(ABSTRACT TRUNCATED AT 250 WORDS)

Formation mechanism of high-Tc and critical current in (Bi,Pb)2Sr2Ca2Cu3O10/Ag tape

Abstract: X-ray diffraction method was used to characterise the phase composition and investigate the formation mechanism of the (Bi,Pb)2Sr2Ca2Cu3O10 phase from the precursor with (Bi,Pb)2Sr2CaCu2O8 as the main phase. The reaction is found to be a two-dimensional nucleation (random)-growth type, −[ ln (1 − F)] 1 2 = kt , where F is the conversional fraction of (Bi,Pb)2Sr2CaCu2O8 and t is the sintering time. The size of the critical current of the tape is quantitatively related to the conversional fraction of (Bi,Pb)2Sr2CaCu2O8 to (Bi,Pb)2Sr2Ca2Cu3O10 phase. At low fraction regime of (Bi,Pb)2Sr2CaCu2O8, the critical current of a tape shows no clear dependence on the remaining Bi-2212 phase, other factors such as grain alignment, colony size, contact between colonies, and fine nonsuperconducting particles become important in controlling the Jc. Also, in this regime, the predominant weak links to be the colony boundaries rather than the Bi-2212 phase.