Host intra-clutch variation, cuckoo egg matching and egg rejection by great reed warblers

Prevailing theory predicts that lower levels of intra-clutch variation in host eggs facilitate the detection of brood parasitism. We assessed egg matching using both human vision and UV-VIS spectrophotometry and then followed the nest fate of great reed warblers naturally parasitised by European cuckoos. Rejection was predicted by the following three variables: matching between cuckoo and host eggs on the main chromatic variable defined by principal components analysis of the egg spectra (which has a strong loading in the UV); the number of host eggs in the nest; and human estimates of intra-clutch variation. The first variable is not correlated to human estimates of matching, which do not predict rejection. In line with another recent study, rejection rates were predicted by higher levels of intra-clutch variation in the host eggs, suggesting that higher rather than lower levels of intra-clutch variation can facilitate the discrimination of cuckoo eggs by hosts. We suggest that the importance of intra-clutch variation is context dependent, with intra-clutch variation being important when there is good matching between the host and the cuckoo eggs. Our results also suggest that both spectrometric and human visual assessments of egg matching and intra-clutch variation are prudent: the former provide the best method of estimating reflectance variation, whereas the latter include some assessment of patterns of maculation.

Do cuckoos choose nests of great reed warblers on the basis of host egg appearance?

Prevailing theory assumes cuckoos lay at random among host nests within a population, although it has been suggested that cuckoos could choose large nests and relatively active pairs within host populations. We tested the hypothesis that egg matching could be improved by cuckoos choosing nests in which host eggs more closely match their own, by assessing matching and monitoring nest fate in great reed warblers naturally or experimentally parasitized by eggs of European cuckoos. A positive correlation between cuckoo and host egg visual features suggests that cuckoos do not lay at random within a population, but choose nests and this improves egg matching: naturally parasitized cuckoo eggs were more similar to host eggs as perceived by humans and as measured by spectrophotometry. Our results suggest a hitherto overlooked step in cuckoo-host evolutionary arms races, and have nontrivial implications for the common experimental practice of artificially parasitizing clutches.

Is tendon pathology a continuum? A pathology model to explain the clinical presentation of load-induced tendinopathy

Overuse tendinopathy is problematic to manage clinically. People of different ages with tendons under diverse loads present with varying degrees of pain, irritability, and capacity to function. Recovery is similarly variable; some tendons recover with simple interventions, some remain resistant to all treatments.

The pathology of tendinopathy has been described as degenerative or failed healing. Neither of these descriptions fully explains the heterogeneity of presentation. This review proposes, and provides evidence for, a continuum of pathology. This model of pathology allows rational placement of treatments along the continuum.

A new model of tendinopathy and thoughtful treatment implementation may improve outcomes for those with tendinopathy. This model is presented for evaluation by clinicians and researchers.

Effect of load pattern on solar-boosted heat pump water heater performance

The performance of a solar-boosted heat pump water heater (HPWH) operating under full load and part load conditions was determined in an outdoor experimental study. The system utilised flat unglazed aluminium solar evaporator panels to absorb solar and ambient energy. Absorbed energy was transferred to the water tank by means of the heat pump and a wrap around condenser coil on the outside of the tank. The system COP was found to be in the range of 5–7 under clear daytime conditions and 3–5 under clear night-time conditions. Using part load testing of the HPWH system it was found that concentrating the coils in the lower portion of the tank could increase the efficiency of the condenser coil. It was also shown that there exists a generalised linear relationship that can be used to describe the system COP in terms of the temperature difference between the water in the storage tank and the ambient air.

Reproductive performance and egg and larval quality of the blacklip abalone

The study highlights the interrelationship between physical characteristics of female broodstock with reproductive performance, egg quality and subsequent larval success, and reproductive seasonality of the blacklip abalone (Haliotis rubra Leach). Suitable indices for assessing broodstock were developed. Seasonal changes in biochemical compositions in relation to maturation and development was discussed.

Isolation, cloning and expression of a putative abalone gene relating to egg-laying hormone

A putative abalone egg-laying hormone has been amplified by polymerase chain reaction (PCR) from abalone genomic DNA. The PCR product was found to hybridize to Lymnaea stagnalis egg-laying hormone (CDCH) cDNA probe and the PCR product was then cloned and sequenced. Nucleotide sequences of putative abalone egg-laying hormone were determined.

Construction of optimal prediction intervals for load forecasting problems

Short-term load forecasting is fundamental for the reliable and efficient operation of power systems. Despite its importance, accurate prediction of loads is problematic and far remote. Often uncertainties significantly degrade performance of load forecasting models. Besides, there is no index available indicating reliability of predicted values. The objective of this study is to construct prediction intervals for future loads instead of forecasting their exact values. The delta technique is applied for constructing prediction intervals for outcomes of neural network models. Some statistical measures are developed for quantitative and comprehensive evaluation of prediction intervals. According to these measures, a new cost function is designed for shortening length of prediction intervals without compromising their coverage probability. Simulated annealing is used for minimization of this cost function and adjustment of neural network parameters. Demonstrated results clearly show that the proposed methods for constructing prediction interval outperforms the traditional delta technique. Besides, it yields prediction intervals that are practically more reliable and useful than exact point predictions.

Transition in wear performance for ionic liquid lubricants under increasing load

The effect of ionic liquid (IL) lubrication for aluminium/steel systems is highly dependant on the applied load and the IL structure. This study illustrates that a change in anion of an IL lubricant results in different physicochemical properties that will alter its performance at a given load. As the load is increased there is a shift in lubricant performance and mechanism of the IL. Up to a load of 30 N the lowest wear coefficient was achieved by a phosphonium diphenylphosphate IL, whilst above 30 N a phosphonium bis(trifluoromethanesulfonyl)amide IL was able to form a more tenacious tribolayer that resulted in the lowest wear.

Load forecasting and neural networks : a prediction interval-based perspective

Successfully determining competitive optimal schedules for electricity generation intimately hinges on the forecasts of loads. The nonstationarity and high volatility of loads make their accurate prediction somewhat problematic. Presence of uncertainty in data also significantly degrades accuracy of point predictions produced by deterministic load forecasting models. Therefore, operation planning utilizing these predictions will be unreliable. This paper aims at developing prediction intervals rather than producing exact point prediction. Prediction intervals are theatrically more reliable and practical than predicted values. The delta and Bayesian techniques for constructing prediction intervals for forecasted loads are implemented here. To objectively and comprehensively assess quality of constructed prediction intervals, a new index based on length and coverage probability of prediction intervals is developed. In experiments with real data, and through calculation of global statistics, it is shown that neural network point prediction performance is unreliable. In contrast, prediction intervals developed using the delta and Bayesian techniques are satisfactorily narrow, with a high coverage probability.

Stimulatory effects of egg-laying hormone and gonadotropin-releasing hormone on reproduction of the tropical abalone, Haliotis asinina linnaeus

Egg-laying hormone (ELH) is a neuropeptide hormone that stimulates ovulation of gastropods, including Aplysia californica and Lymnaea stagnalis. Other neuropeptides, gonadotropin releasing hormones (GnRHs), also play important roles in controlling reproduction in both vertebrates and invertebrates. In the current study, the effects of abalone ELH (aELH) and several GnRHs on somatic growth, sex differentiation, gonad maturation, and spawning of Haliotis asinina were investigated in 3 experiments. In experiment 1, groups of 4-mo-old juveniles (11.8 ±  0.03 mm shell length (SL) and 0.33 ± 0.04 g body weight (BW)) were injected with aELH and GnRHs, including buserelin (mammalian GnRH analogue), octopus GnRH (octGnRH), and tunicate GnRH-I (tGnRH-I), at doses of 20 ng/g BW and 200 ng/g BW. The aELH induced early sex differentiation with a bias toward females, but with normal somatic growth, whereas the different isoforms of GnRH had no effect on sexual differentiation or somatic growth. In experiment 2, groups of 1-y-old-abalone (SL, 4.04 ± 0.02 cm; BW, 20.15 ± 0.25 g) were injected with aELH and the 3 isoforms of GnRH including buserelin, octGnRH, and lamprey GnRH (1GnRH-I) at doses of 500 ng/g BW and 1,000 ng/g BW, and all produced stimulatory effects. For each peptide treatment, the gonads reached full maturation within 5- 6 wk and spawning occurred, whereas control groups took 8 wk to reach maturity. In experiment 3, injections of ripe abalone with aELH stimulated spawning of both sexes in a dose-dependent manner. Buserelin had a lesser effect on inducing spawning, and octGnRH had no apparent effect. The gametes released from induced spawnings by aELH and GnRH showed normal fertilization and development of larvae. Altogether, these findings provide further knowledge on manipulating abalone reproduction, which is important in improving abalone aquaculture.