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Mating behaviour influences the direction and geographic extent of introgression in New Zealand fishing spiders (Dolomedes)
No full textIntrogression is a highly influential process in evolution, where genes flow between species that are not fully reproductively isolated. Studies on introgression often focus on describing gene transfer and environmental changes that facilitate the meeting of species. However, the impact of mating systems and behaviour that facilitate gene transfer is less well-known. Dolomedes aquaticus and D. minor are sister species of fishing spiders undergoing one-way, geographically limited mitochondrial introgression, making them an excellent case study for the factors that promote and limit introgression. We used a combination of field observations and crossing experiments to systematically investigate potential prefertilization barriers that could limit introgression and explain the one-way and geographic barriers to introgression in these species. We found that habitat overlap and timing of reproductive maturity were not likely to be important limiting factors to introgression. However, behaviour was an important factor, with male mate choice being implicated in the geographic limitation, and female mate choice being implicated in the one-way limitation. Our results show the importance of using behavioural approaches in the investigation of introgression
Proximate composition, peptide characterization and bioactive properties of faba bean blanching water
No full textFaba bean (Vicia faba L.) offers a rich nutritional profile with high protein content and abundant vitamins and minerals. Processing of faba beans for freezing requires blanching, yielding liluva (legume processing water), possibly containing leached macronutrients, with potential for upcycling. Past evidence has shown that legume processing water may be high in protein. Peptides generated from faba bean proteins during processing have been shown to have bioactivity and can, for example, inhibit HMG-CoA reductase. HMG-CoA reductase is rate-limiting in the biosynthesis of cholesterols and high cholesterol increases the risk of cardiovascular diseases. Thus, this study examined the composition of legume blanching water, analysed the peptides resulting from in vitro digestion and assayed HMG-CoA reductase inhibitory activity of liluva from faba beans sourced from two farms in Canterbury, New Zealand. Results showed that the blanching water contained around 1.7 g/100 mL solid content. These solids were approximately 30 % protein, 12 % water-soluble carbohydrates, 4 % dietary fibre, and 0.17 % ash. Mineral analysis showed high levels of potassium in macro minerals and zinc in trace minerals. Free amino acid analysis revealed high levels of arginine, alanine, asparagine, and glutamic acid, and low levels of methionine and tryptophan. Mass spectrometry analysis identified 111 and 72 endogenous peptides in farm 1 and 2 raw samples, respectively. Most of these peptides were derived from tripeptidyl-peptidase II and subtilisin-like protease. To understand potential bioactivity of these peptides, peptides were also analyzed after in vitro digestion. The resulting identified peptides indicated in silico predicted bioactivities such as anti-thrombotic, antioxidative, ACE dipeptidyl peptidase −III and −IV inhibition and HMG-CoA reductase inhibition activities. Further validation of the faba bean blanching water after in vitro digestion demonstrated approximately 67 % inhibition of HMG-CoA reductase activity, suggesting potential hypocholesterolemic properties. These findings suggest that faba bean blanching water may serve as a sustainable and functional ingredient with potential cholesterol-lowering effects in food production
Feasibility of using a negative-refractive-index lens to scan reinforced concrete
No full textAn experiment has shown that a negative-refractive-index lens-based imaging system operating at 2.95 GHz can individually resolve 10 mm diameter steel rods submerged in concrete. An analytic model was developed to predict the fields at the surface of concrete as a function of reinforcement rod diameter and depth which was verified using finite-element-method simulations. The model demonstrated phenomena consistent with the experiment and showed that an NRI lens is required to image surface fields. Since the analytic model is computationally efficient compared to simulation, it offers a pathway to extract rod diameter and depth from the imagery
Exposure of Proso millet starch to superheated steam: Effect on physicochemical, techno-functional, rheological behavior, digestibility, and related mechanism
No full textIn the present study, proso millet starch (PMS) was treated with SHS (120–160 °C for 1–5 min) to investigate the molecular interactions and techno-functional, rheological, and digestible properties. Exposure to SHS induced the degradation of helical structure, and longer chains, reducing amylose, blue value, optical density, and relative crystallinity. Meanwhile, SHS treatment might have introduced hydro‑carbonyl groups, eventually increasing water absorption capacity, swelling power, and transparency. As per SEM images, SHS-treated PMS had rough and irregular polygon surfaces with small pinholes. Compared to control, SHS treatment slightly improved the elastic nature of PMS samples. Furthermore, SHS treatment at 140 and 160 °C for 3 and 5 min increased the slowly digestible and resistant starch content. Multivariate analysis suggests that SHS treatment could be performed at 140 °C for 3 min to modify the PMS
Formulation of numerical solutions for Wick Type Stochastic Differential Equations (WSDEs)
No full textIn this chapter, we develop a simple finite difference scheme to approximate the WSDEs using a linear WSDE with constant coefficients. We also compute the solutions and introduce noise ratio as a measure to gauge the influence of noise on the system
Wick algebra, diffusions, and computations
No full textWe summarize pertinent mathematical results in Chap. 2,= and in this chapter, we focus on more useful derivations based on the Wick products with the aim of developing a consistent mathematical machinery for computations. Central to these developments are the Hermite polynomials, and they are used in the Wick products related to the Itô diffusions. The idea of using the Itô diffusions to model the stochastic variables that participate in the Wick type equations is inspired by the fact that many physical variables have drift and diffusive components to them. The forces and flows governed by the physical laws drive the average behaviors in noisy environments and the fluctuations in intrinsic and extrinsic forces and flows give rise to the “noise” in the system. Therefore, it is reasonable to assume that the drift term represents the average behavior, and the diffusion term is a result of the fluctuations. Another important assumption is that the effects of average behaviors and the fluctuations are additive, not multiplicative, and to simplify the analysis, we assume the coefficients associated with these terms are constant
Disabled people, arts festivals and emotional timescapes: An exploratory case study
No full textThis exploratory study contributes to the leisure studies literature in three main ways: through foregrounding the emotionality of intellectually disabled people, an under-represented group within the context of events; through focusing on an arts festival, a form of event overlooked in comparison to other commonly studied types of events; and finally, through the testing of a new methodological framework – Brown’s emotional timescapes for events, itself adapted from Maguire and Geiger’s work on servicescapes. In this New Zealand-based study, we explore the emotions experienced by attendees, performers, volunteers, support workers and event organisers. Data from 20 interviews, participant observation and autoethnography was deductively analysed with a focus on expressions of emotion. We crafted a narrative for each individual, allowing us to identify the influence of the eventscape and map temporal patterns of emotional responses across the festival timescape. Findings show that participants experienced strong positive emotions. This was influenced by elements of the eventscape. In particular, interaction with others (including audience reaction) played a significant role in emotional timescapes. While the emotional timescape model was useful for broadly representing intensity of emotion over the duration of an event, we also identified limitations and propose a way to expand Brown’s theory
Towards a unified theory of supply chain value creation and capture
No full textThe value provided to market by competing supply chains determines success. Thus, a comprehensive understanding of how supply chains create and distribute this value is paramount. The purpose of this research is to synthesis the value creation and value capture concepts in a supply chain context. A case study of an extended agribusiness supply chain is used to empirically explore how value is created and captured with a specific focus on the interplay of the two concepts. The results identify the core value creation drivers and enablers, and value appropriation mediators that determine the net value capture of a supply chain. Insights from the exploratory case study are synthesised into an overarching model. Identification of the symbiotic relationship of value creation and value capture advances our knowledge beyond current discrete conceptualizations. By drawing upon value theory and the empirical insights, the proposed unified theory provides novel implications for theoreticians and managerial decision makers
Mystery on the Bounty: The family-level status of Pacificana cockayni Hogg, 1904 (Araneae)
No full textThe family-level placement of the species Pacificana cockayni Hogg, 1904 (Araneae, Miturgidae) has been ambiguous for over a century, with the monotypic genus Pacificana initially placed in Agelenidae, later transferred to Amaurobioidinae (Anyphaenidae), and presently in Miturgidae. A recent work describing the male and molecular data consisting of a single mitochondrial gene, cytochrome c oxidase subunit I, confirmed that the species is part of the marronoid clade; however, these data did not result in a conclusive family-level placement. Here, we use low-coverage whole genome sequencing (lcWGS) combined with data from the Sequence Read Archive to infer a phylogeny from ultraconserved elements (UCEs) and six legacy Sanger loci. Indications of potential family placements from prior work and the topologies from this study support a transfer of Pacificana Hogg, 1904 to Cycloctenidae Simon, 1898 (new family placement)
An investigation of deterministic chemical reactions and their stability
No full textIn this chapter, we discuss deterministic chemical reactions in the closed and open systems. We attempt to understand the stability of stationary states in both situations using the excess entropy production, which we discuss in Chap. 1. Then we investigate the behavior of the reactions using numerical solutions. We use three examples to illustrate that the deterministic formulations of chemical reactions lead to complex behavior patterns even without potential noise in systems. In open systems, reactions can easily be oscillatory depending on the reaction rate coefficients and initial conditions. However, the existence of nonequilibrium stationary states (NESSs) in dissipative structures is well documented, the analysis presented here is heuristic to show the complexities prior to delving into stochastic situations in next two chapters