Digestive and locomotor capacity show opposing responses to changing food availability in an ambush predatory fish

Metabolic rates vary widely within species, but little is known about how variation in the “floor” (i.e. standard metabolic rate in ectotherms; SMR) and “ceiling” (maximum metabolic rate; MMR) for an individual's aerobic scope (AS) are linked with the digestive and locomotor function. Any links among metabolic traits and aspects of physiological performance may also be modulated by fluctuations in food availability. This study followed changes in SMR, MMR, and digestive and locomotor capacity in Southern catfish (Silurus meridionalis) throughout 15 days of food deprivation and 15 days of refeeding. Individuals down-regulated SMR during food deprivation and showed only a 10% body mass decrease during this time. While critical swim speed (Ucrit), was robust to food-deprivation, digestive function decreased after fasting with a reduced peak oxygen uptake during specific dynamic action (SDA) and prolonged SDA duration. During refeeding, individuals displayed rapid growth and digestive function recovered to pre-fasting levels. However, refed fish showed a lower Ucrit than would be expected for their increased body length and in comparison to measures at the start of the study. Reduced swimming ability may be a consequence of compensatory growth: growth rate was negatively correlated with changes in Ucrit during refeeding. Southern catfish down-regulate digestive function to reduce energy expenditure during food deprivation, but regain digestive capacity during refeeding, potentially at the cost of decreased swimming performance. The plasticity of maintenance requirements suggests that SMR is a key fitness trait for in this ambush predator. Shifts in trait correlations with food availability suggest that the potential for correlated selection may depend on context

The 1980-90 shuttle star catalog for onboard and ground programs

The 1980-90 shuttle star catalog for onboard and ground programs is presented. The data used in this catalog are explained according to derivation, input, format for the catalog, and preparation. The tables include the computer program listing, input star position, and the computed star positions for the years 1980-90

Modelling fat and protein concentration curves for Irish dairy cows

peer-reviewedThe objective of this study was to acquire a well-fitting, single-equation model that would represent the fat and protein concentration curves of milk from Irish dairy cows. The dataset consisted of 16,086 records from both spring and autumn calving cows from both experimental and commercial herds. Many models cited in the literature to represent milk yield were examined for their suitability to model constituent curves. Models were tested for goodness-of-fit, adherence to the assumptions of regression analysis, and their ability to predict total fat and protein concentration for an entire lactation. Wilmink’s model best satisfied these criteria. It had the best Mean Square Prediction Error (goodness-of-fit) value, it satisfied the assumptions of regression analysis (multicollinearity, heteroskedasticity, autocorrelation and normality of distribution), and it predicted the actual concentration of the constituents to within 0.01 percentage point

Parents' experiences of sharing neonatal information and decisions: Consent, cost and risk

This paper is about the care of babies with confirmed or potential neurological problems in neonatal intensive care units. Drawing on recent ethnographic research, the paper considers parents' experiences of sharing information and decisions with neonatal staff, and approaches that support or restrict parents' involvement. There are growing medico-legal pressures on practitioners to inform parents and involve them in their babies' care. Data are drawn from observations in four neonatal units in southern England, and interviews with the parents of 80 babies and with 40 senior staff. The paper compares standards set by recent guidance, with parents' views about their share in decision-making, their first meetings with their babies, 'minor' decision-making, the different neonatal units, being a helpless observer and missed opportunities. Parents' standards for informed decisions are summarised, with their reported views about two-way decision-making, and their practical need to know. Whereas doctors emphasise distancing aspects of the consent process, parents tend to value 'drawing together' aspects

The distribution of atomic hydrogen in the Jovian atmosphere

An analysis is presented of the Voyager and IUE lyman alpha spectra of the Jovian equatorial emission in which was derived a zonal asymmetry in the hydrogen column abundance. Using two estimates of the fraction of Lyman alpha which is due to direct excitation by charged particle precipitation from the ionosphere, upper and lower limits were derived to the H column abundance within and without the perturbed region. That the asymmetry in H abundance may be due to localized heating near the homopause with a consequent rise in scale height is shown. The derived exospheric temperature remains fairly constant with longitude. The required additional heat input over the bulge region, 0.02 erg/cm/s, is supplied by an additional flux of magnetospheric electrons due to Jupiter's magnetic anomaly

Detection of abnormal recordings in Irish milk recorded data

peer-reviewedThe objective of this study was to detect abnormal recordings of milk yield, fat concentration and protein concentration in Irish milk-recorded data. The data consisted of 14,956 records from both commercial and experimental herds with 92% of the recordings recorded manually and the remainder recorded electronically. The method used in this paper was a modified version of the method employed by the Animal Improvement Programs Laboratory in Maryland, USA and conformed with the guidelines outlined by the International Committee of Animal Recording. The results illustrate the effectiveness of detecting abnormal recordings in Irish milk records. The method described in this paper, defines the upper and lower limits for each production trait and these limits along with the slope parameters were used to determine if a recording was abnormal or not. Three percent of milk yield recordings, 5% of fat concentration recordings and less than 1% of protein concentration recordings were found to be abnormal. The proportion of values declared abnormal in manually recorded and electronically recorded data were examined and found to be significantly different for fat concentration

Now you see her, now you don’t: U.S. women and the current battle over contraception

In this post, LSE MSc Gender, Media, and Culture student Kimberly Killen reviews the current debate over contraception in the U.S.A. and asks, ‘Where are the women?

The Regional Dimension of Industrial Policy and Performance in the Republic of Ireland

From its inception in the late 1940s, Irish industrial policy has attempted to disperse industrial plants across regions, thereby avoiding the problem of rural-urban migration experienced by many developing countries. Analysing a large sample of companies which established in Ireland in the early 1980s, we examine whether the survival rates of companies and jobs are lower in peripheral compared with core regions, and whether indigenous and foreign companies differ in this regard. We find higher (lower) company and job survival rates for indigenous (foreign) companies at the core than at the periphery.

The interplay between aerobic metabolism and antipredator performance: vigilance is related to recovery rate after exercise

When attacked by a predator, fish respond with a sudden fast-start motion away from the threat. Although this anaerobically-powered swimming necessitates a recovery phase which is fueled aerobically, little is known about links between escape performance and aerobic traits such as aerobic scope (AS) or recovery time after exhaustive exercise. Slower recovery ability or a reduced AS could make some individuals less likely to engage in a fast-start response or display reduced performance. Conversely, increased vigilance in some individuals could permit faster responses to an attack but also increase energy demand and prolong recovery after anaerobic exercise. We examined how AS and the ability to recover from anaerobic exercise relates to differences in fast-start escape performance in juvenile golden gray mullet at different acclimation temperatures. Individuals were acclimated to either 18, 22, or 26°C, then measured for standard and maximal metabolic rates and AS using intermittent flow respirometry. Anaerobic capacity and the time taken to recover after exercise were also assessed. Each fish was also filmed during a simulated attack to determine response latency, maximum speed and acceleration, and turning rate displayed during the escape response. Across temperatures, individuals with shorter response latencies during a simulated attack are those with the longest recovery time after exhaustive anaerobic exercise. Because a short response latency implies high preparedness to escape, these results highlight the trade-off between the increased vigilance and metabolic demand, which leads to longer recovery times in fast reactors. These results improve our understanding of the intrinsic physiological traits that generate inter-individual variability in escape ability, and emphasize that a full appreciation of trade-offs associated with predator avoidance and energy balance must include energetic costs associated with vigilance and recovery from anaerobic exercise

Labor Force Commute Mode Preferences and the Natural Environment

In commuting to work, commuters select from a limited variety of transportation modes, including alternative modes like cycling and walking, based on needs and preferences. Understanding these needs and preferences, and how the conditions of the immediate environment can influence them can benefit both businesses and local governments in their efforts to accommodate the commute needs of their workers and better serve their communities. Though the body of commute preference research has grown significantly over recent decades, the study of the effects of the natural environment has remained mostly overlooked. In my research, I examined the relationships between selected weather conditions of the natural environment and the percentage of the labor force that cycled or walked to work in large U.S. cities. To explore these relationships, I employed multicollinaerity and multiple linear regression analysis of the percentage of the labor force that commuted by cycling or walking in the two largest cities of each state with eight observed conditions of the natural environment in each city: the mean daily maximum temperature; the mean daily minimum temperature; the number of days per year in which fog limited visibility to less than or equal to one-quarter mile; the number of days per year with thunderstorms; the mean wind speed; the total water equivalent precipitation; the total amount of snow, ice, pellets, and hail; and the total number of days with snowfall greater than or equal to one inch. The results of my statistical analysis revealed that only two variables (the number of days per year with thunderstorms and the total water equivalent precipitation) exhibited significant relationships with the percentage of work commuters who cycled or walked. Furthermore, the number of days per year with thunderstorms exhibited a strong inverse relationship, meaning that thunderstorms deterred workers from cycling or walking to work. These relationships confirmed the significant influence that precipitation, as a condition of the natural environment, can bear on commute preferences. Based on these findings, businesses can better understand their employees and improve their productivity and reputations within their communities by accommodating the differences in commute mode preferences across varying climatological regions