Adaptability of great cormorants Phalacrocorax carbo in a coastal environment demonstrated by their exploitation of introduced prey species and use of artificial breeding sites

An analysis of the contents of regurgitations of great cormorant Phalacrocorax carbo chicks at two coastal colonies in South Africa, one on an offhore island (St Croix) and the other at a saltworks in an estuary (Swartkops), revealed that the diet was dominated by introduced freshwater and estuarine fish. Most other prey species were indigenous euryhaline fish, and from the size ranges of the estuary-dependent species it was clear that they had been obtained in estuaries. Great cormorants in this coastal environment have learned to exploit introduced fish species, but use offshore islands as safe breeding sites, unless suitably safe artificial sites are created near their preferred foraging areas.Keywords: chick regurgitations, diet, St Croix Island, Swartkops RiverAfrican Journal of Marine Science 2002, 24: 317–32

A Proof Strategy Language and Proof Script Generation for Isabelle/HOL

We introduce a language, PSL, designed to capture high level proof strategies in Isabelle/HOL. Given a strategy and a proof obligation, PSL's runtime system generates and combines various tactics to explore a large search space with low memory usage. Upon success, PSL generates an efficient proof script, which bypasses a large part of the proof search. We also present PSL's monadic interpreter to show that the underlying idea of PSL is transferable to other ITPs.Comment: This paper has been submitted to CADE2

Mimicking exercise in three-dimensional bioengineered skeletal muscle to investigate cellular and molecular mechanisms of physiological adaptation

Bioengineering of skeletal muscle in vitro in order to produce highly aligned myofibres in relevant three dimensional (3D) matrices have allowed scientists to model the in vivo skeletal muscle niche. This review discusses essential experimental considerations for developing bioengineered muscle in order to investigate exercise mimicking stimuli. We identify current knowledge for the use of electrical stimulation and co-culture with motor neurons to enhance skeletal muscle maturation and contractile function in bioengineered systems in vitro. Importantly, we provide a current opinion on the use of acute and chronic exercise mimicking stimuli (electrical stimulation and mechanical overload) and the subsequent mechanisms underlying physiological adaptation in 3D bioengineered muscle. We also identify that future studies using the latest bioreactor technology, providing simultaneous electrical and mechanical loading and flow perfusion in vitro, may provide the basis for advancing knowledge in the future. We also envisage, that more studies using genetic, pharmacological, and hormonal modifications applied in human 3D bioengineered skeletal muscle may allow for an enhanced discovery of the in-depth mechanisms underlying the response to exercise in relevant human testing systems. Finally, 3D bioengineered skeletal muscle may provide an opportunity to be used as a pre-clinical in vitro test-bed to investigate the mechanisms underlying catabolic disease, while modelling disease itself via the use of cells derived from human patients without exposing animals or humans (in phase I trials) to the side effects of potential therapies

Population structure and genetic management of Rio Grande cutthroat trout (Oncorhynchus clarkii virginalis)

The Rio Grande cutthroat trout, Oncorhynchus clarkii virginalis, has declined precipitously over the past century, and currently exhibits a highly fragmented distribution within the Canadian, Pecos and Rio Grande river systems of the western United States. The relationships between populations in the three river drainages, and between O. c. virginalis and the closely related taxa O. c. pleuriticus and O. c. stomias, are not well understood. In order to guide management decisions for the subspecies, we investigated the distribution of variation at 12 micro-satellite loci and two regions of the mitochondrial genome. We observed a high level of genetic differentiation between O. c. virginalis populations occupying different headwater streams ( global F-st = 0.41). However, we found evidence for previous gene flow within the Rio Grande drainage, indicating that inter-population differentiation may have been exacerbated by the recent effects of population fragmentation. Despite large-scale anthropogenic movement of individuals from the Rio Grande into the Canadian and Pecos, the genetic signature of long-term evolutionary independence between the three drainages has been retained

Characterization of tetranucleotide microsatellites for Rio Grande cutthroat trout and rainbow trout, and their cross-amplification in other cutthroat trout subspecies

We describe the isolation and characterization of 12 tetranucleotide microsatellites for Rio Grande cutthroat trout (Oncorhynchus clarkii virginalis) and rainbow trout (Oncorhynchus mykiss), and subsequently investigate their performance in Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus), greenback cutthroat trout (Oncorhynchus clarkii stomias) and Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri). All 12 loci are polymorphic in all subspecies of O. clarkii examined

Simple study designs in ecology produce inaccurate estimates of biodiversity responses

Monitoring the impacts of anthropogenic threats and interventions to mitigate these threats is key to understanding how to best conserve biodiversity. Ecologists use many different study designs to monitor such impacts. Simpler designs lacking controls (e.g. Before-After (BA) and After) or pre-impact data (e.g. Control-Impact (CI)) are considered to be less robust than more complex designs (e.g. Before-After Control-Impact (BACI) or Randomised Controlled Trials (RCTs)). However, we lack quantitative estimates of how much less accurate simpler study designs are in ecology. Understanding this could help prioritise research and weight studies by their design’s accuracy in meta-analysis and evidence assessment. 2. We compared how accurately five study designs estimated the true effect of a simulated environmental impact that caused a step-change response in a population’s density. We derived empirical estimates of several simulation parameters from 47 ecological datasets to ensure our simulations were realistic. We measured design performance by determining the percentage of simulations where: (i) the true effect fell within the 95% Confidence Intervals of effect size estimates, and (ii) each design correctly estimated the true effect’s direction and magnitude. We also considered how sample size affected their performance. 3. We demonstrated that BACI designs performed: 1.3-1.8 times better than RCTs; 2.9-4.2 times vs BA; 3.2-4.6 times vs CI; and 7.1-10.1 times vs After designs (depending on sample size), when correctly estimating true effect’s direction and magnitude to within ±30%. Although BACI designs suffered from low power at small sample sizes, they outperformed other designs for almost all performance measures. Increasing sample size improved BACI design accuracy but only increased the precision of simpler designs around biased estimates. 4. Synthesis and applications. We suggest that more investment in more robust designs is needed in ecology since inferences from simpler designs, even with large sample sizes may be misleading. Facilitating this requires longer-term funding and stronger research-practice partnerships. We also propose ‘accuracy weights’ and demonstrate how they can weight studies in three recent meta-analyses by accounting for study design and sample size. We hope these help decision-makers and meta-analysts better account for study design when assessing evidence

Non-Keynesian Effects of Fiscal Consolidations in Central Europe in the Years 2000-2013

Last two decades were a period of significant discussion concerning determinants of effectiveness of fiscal policy. After some cases of expansionary episodes of fiscal consolidations in eighties of XX century, an intensive international research on the possibility of non-Keynesian effects of fiscal contractions in highly developed countries has started. The aim of the article is to analyze the possibility of obtaining non-Keynesian effects of fiscal consolidations in post-transformation countries of Central Europe. An important aim of macroeconomic policy in the analyzed economies is to benefit the advantages of convergence process. Thus, the empirical analysis is made within conditional β-convergence framework. The verification of hypothesis of β-convergence enables to identify the long term tendency of output per capita, in the same time it enables to identify non-Keynesian effects of fiscal prudence and to assess their role in the process of reducing GDP gap between the analyzed economies. Then the potential transmission channels for non-Keynesian effects of fiscal policy were analyzed. In the research the data from Eurostat and European Commission for the years 2000-2013 was used. The paper provides arguments in favor of the existence of non-Keynesian effects of fiscal consolidations in Central Europe that support the process of conditional convergence