Aim We used a combination of new and previously published palaeoecological data to test three hypotheses: (

The effect of ration on the growth of the three-spined stickleback, Gasterosteus aculeutus, was studied over the temperature range 3-19" C, which corresponded to the range in their natural habitat. With an ad lib ration, the specific growth rate increased with temperature. The relationship between specific growth rate and ration at a given temperature was curvilinear. Regression models were used to predict the maximum, optimum and maintenance rations at each temperature. Whereas maximum ration increased rapidly with temperature, the optimum and maintenance rations were relatively insensitive to temperature. A regression model was used to describe the overall relationship between specific growth rate and ration, temperature and body weight. This model predicted that at low rations, growth rate decreased with temperature, whereas at high rations, growth rate increased slightly with temperature. The gross growth efficiency increased rapidly with rations above maintenance ration up to a maximum at the optimum ration and declined at higher rations. The maximum gross growth efficiencies were at high temperatures and rations about half of the maximum ration. The maximum net growth efficiencies occurred at relatively low temperature and at rations just above maintenance.

1. Monthly and diel patterns of food consumption by the three-spined stickleback, Gasterosteus aculeatus L., were studied in Llyn Frongoch, a small reservoir in upland mid-Wales.2. Copepods were particularly prominent in the diet in spring and autumn, with ephemeropteran nymphs prominent in summer. Chironomid pupae and stickleback eggs were also elements of the diet in summer, whereas algae, plant material and debris were more important in autumn and winter. Chironomid larvae and ostracods were present throughout the year, but there was some doubt as to the importance of ostracods as digestible food items.3. Stomach contents were heaviest in spring and late summer and lightest in late autumn and winter. 4. Samples for the diel samples were taken four times, once in each season. These diel samples largely reflected the seasonal changes in diet noted in the monthly samples. There were few cases of a clear switch in the composition of the diet during a 24 h period.

In a population of Gasterosteus aculeatus living in an infertile, upland lake, the fish bred at the age of one year and few survived to breed again. The highest growth rates were achieved in the first month of life, but in comparison with other populations of G. aculeatus growth was slow during the autumn and ceased during the winter. But in spring and early summer, there was a spurt in the growth rate.Laboratory studies provided regression models for the prediction of the rate of food consumption from measurements of growth. The estimates of the consumption rate indicated the effect of the growth in body size and seasonal variations during the first year of life. It was estimated that a fish of mean length in the population consumed 3 150 mg of food in a year in which it grew from 65.8 to 552.0 mg, with an overall gross growth efficiency of 15.4%.The study illustrated the integration of laboratory and field studies to obtain reasonable estimates of the rate of food consumption by fish throughout their first year of life.

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ABSTRACT. Glacier basal motion generates diurnal to multi-annual fluctuations in glacier velocity and mass flux. Understanding these fluctuations is important for prediction of future sea-level rise and for gaining insight into glacier physics and erosion. Here, we derive glacier velocity through cross-correlation of WorldView satellite imagery to document the evolution of ice surface velocity on Kennicott Glacier, Alaska, over the 2013 melt season. The summer speedup is spatially uniform over a ∼12 km 2 area, over which the spring velocity varies significantly. Velocity increases by 1.4-fold to tenfold across the study domain, with larger values where spring velocities are low. To investigate the crossglacier distribution of basal motion required to explain the observed surface speedup, we employ a two-dimensional cross-sectional glacier flow model. We find the model is insensitive to the spatial distribution of basal slip because stress gradient ice coupling diffuses the surface expression of the basal velocity field. While the temporal evolution of the subglacial hydrologic system is critical for predicting a glacier's response to meltwater inputs, our work suggests that glacier and ice-sheet models do not require a detailed representation of subglacial hydrology to accurately capture the spatial pattern of glacier speedup.

The relationships between the maximum, daily food consumption, body weight and water temperature for the stickleback, Gasterosteus aculeatus L., and the minnow, Phoxinus phoxinus (L.), were studied. The two species occupy the same lakes in mid-Wales, but differ in that G. aculeatus has a true stomach whereas P. phoxinus lacks a true stomach.For both species, the relationship between food consumption (F) and body weight ( W) could be described by the model: lo F -a + b log, W. The effect of temperature ( g could be incorporated in the form: Iok%A + b, log, W + b, log, T. These models were selected because they accounted for a high proportion of the variance in the dependent variable, and because an analysis of the residuals obtained after fitting a model showed no trends which would have signalled the inadequacy ofthe model.

As the battery industry shifts toward high Ni content cathodes, such as LiNi0.8Mn0.1Co0.1O2 [NMC811], a complete understanding of the degradation mechanisms of NMC811 under extreme fast charging (XFC) (XFC, ≤10–15 min charging) conditions is needed. Such comprehensive understanding would identify the most critical materials gaps that need to be addressed for enabling XFC long‐life cells for electric vehicles. This study maps out the key aging mechanisms for NMC811 cycled at different XFC conditions (between 1C and 9C) for up to 1000 cycles. To acquire a fundamental understanding of utilization and degradation, cells are evaluated using a range of electrochemical techniques, and multimodal and multiscale microscopy techniques to quantify chemical, structural, and crystallographic degradation as a function of cycling conditions for the NMC cathode. When comparing NMC811 to NMC532, it is observed that NMC811 has a greater subsurface crystallographic degradation and displays a similar magnitude of subparticle cracking. However, the NMC811 maintains superior performance despite those advanced degradations. The superior cycle life performance is attributed to the NMC811 particles having radially oriented grains and improved transport properties. NMC811 shows between 4.6× and 3.15× reduction in capacity fade than NMC532 for charging rates between 4C (e.g., 15‐min charging) and 6C (10‐min charging).