Persistent current of one-dimensional perfect rings under the canonical ensemble

We have analyzed the harmonic contents of the persistent current at high temperatures under the canonical ensemble. Results show that the behavior of each harmonic is different from that under the grand-canonical ensemble. The persistent current of the multiring system is also presented.published_or_final_versio

Using Quantum Cheshire Cats to explore Contextuality and Quantum Coherence

We analyse the quantum Cheshire cat using contextuality theory. The results shed a surprising new light on the relation between quantum paradoxes, weak values, and contextuality, a key resource for quantum computing. \ua9 2024 The Author(s

Counterfactuality, back-action, and information gain in multi-path interferometers

The presence of an absorber in one of the paths of an interferometer changes the output statistics of that interferometer in a fundamental manner. Since the individual quantum particles detected at any of the outputs of the interferometer have not been absorbed, any non-trivial effect of the absorber on the distribution of these particles over these paths is a counterfactual effect. Here, we quantify counterfactual effects by evaluating the information about the presence or absence of the absorber obtained from the output statistics, distinguishing between classical and quantum counterfactual effects. We identify the counterfactual gain which quantifies the advantage of quantum counterfactual protocols over classical counterfactual protocols, and show that this counterfactual gain can be separated into two terms: a semi-classical term related to the amplitude blocked by the absorber, and a Kirkwood-Dirac quasiprobability assigning a joint probability to the blocked path and the output port. A negative Kirkwood-Dirac term between a path and an output port indicates that inserting the absorber into that path will have a focussing effect, increasing the probability of particles arriving at that output port, resulting in a significant enhancement of the counterfactual gain. We show that the magnitude of quantum counterfactual effects cannot be explained by a simple removal of the absorbed particles, but originates instead from a well-defined back-action effect caused by the presence of the absorber in one path, on particles in other paths

The development and neuronal complexity of bipinnaria larvae of the sea star Asterias rubens

Free-swimming planktonic larvae are a key stage in the development of many marine phyla, and studies of these organisms have contributed to our understanding of major genetic and evolutionary processes. Although transitory, these larvae often attain a remarkable degree of tissue complexity, with well-defined musculature and nervous systems. Amongst the best studied are larvae belonging to the phylum Echinodermata, but with work largely focused on the pleuteus larvae of sea urchins (class Echinoidea). The greatest diversity of larval strategies amongst echinoderms is found in the class Asteroidea (sea-stars), organisms that are rapidly emerging as experimental systems for genetic and developmental studies. However, the bipinnaria larvae of sea stars have only been studied in detail in a small number of species and although they have been relatively well described neuro-anatomically, they are poorly understood neuro-chemically. Here we have analysed embryonic development and bipinnaria larval anatomy in the common North Atlantic sea-star Asterias rubens, employing use of a variety of staining methods in combination with confocal microscopy. Importantly, the chemical complexity of the nervous system of bipinnaria larvae was revealed with a diverse set of antibodies, with identification of at least three centres with different neuro-chemical signature within the previously described nervous system: the anterior apical organ, oral region and ciliary bands. Furthermore, the anatomy of the musculature and sites of cell division in bipinnaria larvae were analysed. Comparisons of developmental progression and molecular anatomy across the Echinodermata provided a basis for hypotheses on the shared evolutionary and developmental processes that have shaped this group of animals. We conclude that bipinnaria larvae appear to be remarkably conserved across ∼200 million years of evolutionary time and may represent a strong evolutionary and/or developmental constraint for species utilizing this larval strategy

Effect of dietary energy level on growth performance and morphometric parameters of local barred chickens at the starter phase

An experiment was conducted to determine the influence of dietary energy level on the growth performance and morphometric characteristics of local barred chicks. The experiment lasted for 12 weeks. Three hundred and twenty day-old barred chicks were assigned to four different dietary treatments, having four replicates of 20 chicks each. Treatments consisted of D0, D1, D2 and D3 containing 2700, 2800, 2900 and 3000 kcal/kg of metabolisable energy respectively. The highest BW (868 g) and BWG (830 g) were recorded with treatment D1 and D3 (844 g and 804 g respectively). These values were significantly (P<0.05) higher compared to D0 and D2. The feed conversion ratio were significantly (P < 0.05) higher with  treatments D0 and D2 as compared to treatments D1 and D3. Feed cost per kg of body weight was significantly (P<0.05) lower for treatment D1 as compared to other treatments. Thus, metabolisable energy requirement of local barred chicks between 1 to 12 weeks is 2800 kcal/kg.Keywords: Barred chickens, dietary energy, starter phase

Counterfactual control and quantum contextuality in multi-mode interferometers

As shown in previous work, quantum contextuality can be represented by interference effects in a three-path interferometer. A Hardy-like paradox is obtained when the absence of photons in two internal paths seems to contradict the presence of photons in a specific input port. Here, we consider the effects of counterfactual control on this scenario by analyzing the changes to the paths through the interferometer when the seemingly impossible input path is blocked. The effects on photons that never interact with the absorber in the blocked path reveals a characteristic signature of quantum contextuality that may help to explain why quantum interference is incompatible with measurement independent realities

Estimating maturity from size-at-age data: are real-world fisheries datasets up to the task?

The size and age at which individuals mature is rapidly changing due to plastic and evolved responses to fisheries harvest and global warming. Understanding the nature of these changes is essential because maturity schedules are critical in determining population demography and ultimately, the economic value and viability of fisheries. Detecting maturity changes is, however, practically difficult and costly. A recently proposed biphasic growth modelling likelihood profiling method offers great potential as it can statistically estimate age-at-maturity from population-level size-at-age data, using the change-point in growth that occurs at maturity. Yet, the performance of the method on typical marine fisheries datasets remains untested. Here, we assessed the suitability of 12 North Sea and Australian species’ datasets for the likelihood profiling approach. The majority of the fisheries datasets were unsuitable as they had too small sample sizes or too large size-at-age variation. Further, datasets that did satisfy data requirements generally showed no correlation between empirical and model-derived maturity estimates. To understand why the biphasic approach had low performance we explored its sensitivity using simulated datasets. We found that method performance for marine fisheries datasets is likely to be low because of: (1) truncated age structures due to intensive fishing, (2) an under-representation of young individuals in datasets due to common fisheries-sampling protocols, and (3) large intrapopulation variability in growth curves. To improve our ability to detect maturation changes from population level size-at-age data we need to improve data collection protocols for fisheries monitoring

Effect of Dietary Components on Larval Life History Characteristics in the Medfly (Ceratitis capitata: Diptera, Tephritidae)

Background: The ability to respond to heterogenous nutritional resources is an important factor in the adaptive radiation of insects such as the highly polyphagous Medfly. Here we examined the breadth of the Medfly’s capacity to respond to different developmental conditions, by experimentally altering diet components as a proxy for host quality and novelty. Methodology/Principal Findings: We tested responses of larval life history to diets containing protein and carbohydrate components found in and outside the natural host range of this species. A 40% reduction in the quantity of protein caused a significant increase in egg to adult mortality by 26.5%±6% in comparison to the standard baseline diet. Proteins and carbohydrates had differential effects on larval versus pupal development and survival. Addition of a novel protein source, casein (i.e. milk protein), to the diet increased larval mortality by 19.4%±3% and also lengthened the duration of larval development by 1.93±0.5 days in comparison to the standard diet. Alteration of dietary carbohydrate, by replacing the baseline starch with simple sugars, increased mortality specifically within the pupal stage (by 28.2%±8% and 26.2%±9% for glucose and maltose diets, respectively). Development in the presence of the novel carbohydrate lactose (milk sugar) was successful, though on this diet there was a decrease of 29.8±1.6 µg in mean pupal weight in comparison to pupae reared on the baseline diet. Conclusions: The results confirm that laboratory reared Medfly retain the ability to survive development through a wide range of fluctuations in the nutritional environment. We highlight new facets of the responses of different stages of holometabolous life histories to key dietary components. The results are relevant to colonisation scenarios and key to the biology of this highly invasive species

Smaller adult fish size in warmer water is not explained by elevated metabolism

Fish and other ectotherms living in warmer waters often grow faster as juveniles, mature earlier, but become smaller adults. Known as the temperature-size rule (TSR), this pattern is commonly attributed to higher metabolism in warmer waters, leaving fewer resources for growth. An alternative explanation focuses on growth and reproduction trade-offs across temperatures. We tested these hypotheses by measuring growth, maturation, metabolism and reproductive allocation from zebrafish populations kept at 26 and 30°C across six generations. Zebrafish growth and maturation followed TSR expectations but were not explained by baseline metabolic rate, which converged between temperature treatments after a few generations. Rather, we found that females at 30°C allocated more to reproduction, especially when maturing at the smallest sizes. We show that elevated temperatures do not necessarily increase baseline metabolism if sufficient acclimation is allowed and call for an urgent revision of modelling assumptions used to predict population and ecosystem responses to warming