Full Length Research Paper Biochemical and textural properties of frozen stored (-22°C) gilthead seabream (Sparus aurata) fillets

Skinned, vacuum packed post-rigor gilthead seabream (Sparus aurata) fillets were stored frozen at -22°C for up to 340 days. Sampling was carried out on fresh fillets at days 34, 91, 183, 266 and 340 offrozen storage. Tests related to muscle integrity (activity of -glucosidase and the protein content of centrifugal tissue fluids), myofibrillar protein denaturation (Ca2+- and Mg2+-ATPase activities inactomyosin extracts) and lipid degradation products (free fatty acids, peroxide values and thiobarbituric reactive substances) showed that storage time affected the integrity of muscles, and caused structural changes to myosin (or ‘actomyosin’) and hydrolysis and oxidation of lipids. A slight decrease in salt soluble proteins was observed after 266 days of frozen storage suggesting that storage time hardly affected the formation of aggregates. The water holding capacity of the stored frozen fillets decreased with storage time and was associated with the damage in muscle structures (protein content in centrifugal tissue fluids), denaturation of myofibrillar proteins and lipid degradation products (freefatty acids and peroxide value). The firmness and toughness of the frozen fillets, as measured by the Warner-Bratzler shear knife, increased slightly with storage time. The changes in toughness were associated with the state of myofibrillar proteins and changes in water holding capacity of the stored frozen fillets

The biochemical, textural and sensory properties of king scallop (Pecten maxinus) meats frozen at different characteristic freezing times

Post rigor scallop meats were frozen individually with characteristic freezing time of 19, 49, 89, 235, 555 and 1000 min (time to cool the thermal centre of the meats from -1 to -7°C). After freezing, the meats were thawed and their quality was evaluated with tests related to muscle integrity (-hydroxy-acylcoenzyme –A dehydrogenase activities in muscle extracts), freezing and thawing losses, expressible fluids and myofibrillar protein denaturation (Ca2+-ATPase activities in actomyosin extracts).Instrumental texture measurements and triangular sensory evaluations were also performed. Fresh post-rigor meats were analyzed as controls. The muscle integrity test showed that the freezing process itself clearly affected the integrity of intra-cellular organelles (mitochondria). The characteristic freezing time of 89 and 49 min caused more damage to cell structure than the shorter and longer characteristic freezing time tested. Ca2+- ATPase activities of actomyosin extracts suggested that the freezingprocess itself, but not the freezing time, caused structural damage to myofibrillar proteins and were associated with the changes in water holding capacity (sum of thawing and expressible fluids). Peak shear forces of fresh and frozen scallop meats, as measured by the Warner-Bratzler shear knife, showed that only the freezing process itself caused softening of scallop meats. Triangle sensory comparisons between fresh and frozen scallop muscles suggested that characteristic freezing times up to 555 min may not influence the sensory quality of frozen scallop meats. Freezing of meats at the short freezing time of 19 min reduced freezing and thawing weight losses compared to longer time tested

Influence of socioemotional wealth on non-family managers’ risk taking and product innovation in family businesses

Purpose: There is a growing interest in understanding family firms’ strategic behavior using the socioemotional wealth perspective. This study explores how family socioemotional wealth (SEW) dimensions influence non-family managers’ attitudes toward risk in the context of product innovation. We also examine whether managerial risk-taking mediates the relationship between SEW and product innovation. Design/methodology/approach: The study uses a sample of 150 family firms in the United Arab Emirates and collects data from family owners and non-family managers via self-administered questionnaires. We use SmartPLS structural equation modeling to test the conceptual model and the proposed hypotheses. Findings: The results indicate that SEW influences non-family managers’ risk-taking behavior in different magnitudes and directions, thus impacting firms’ product innovation. Moreover, risk-taking partially mediates the relationship between SEW dimensions and product innovation. Originality/value: While product innovation could be seen as a loss scenario for family firms due to the potential loss of SEW, growth, continuity, and reputation outweighed the desire to maintain control for the firms in this sample. Thus, these firms encourage non-family managers to take risks in product innovation

Dynamics of Post-Injection Fuel Flow in Mini-Sac Diesel Injectors Part 1: Admission of 1 External Gases and Implications for Deposit Formation

Samples of unadditized, middle distillate diesel fuel were injected through real-size optically accessible mini-sac diesel injectors into ambient air at common rail pressures of 250 bar and 350 bar respectively. High-resolution images of white light scattered from the internal mini-sac and nozzle flow were captured on a high-speed monochrome video camera. Following the end of each injection, the momentum-driven evacuation of fuel liquid from the mini-sac and nozzle holes resulted in the formation of a vapour cloud and bubbles in the mini-sac, and vapour capsules in the nozzle holes. This permitted external gas to gain entrance to the nozzle holes. The diesel fuel in the mini-sac was observed to rotate with large initial vorticity, which decayed until the fuel became stationary. The diesel fuel remaining in the nozzle holes was observed to move inwards towards the mini-sac or outwards towards the nozzle exit in concert with the rotational flow in the mini-sac. The mini-sac bubbles’ internal pressure differences revealed that the bubbles must have contained previously dissolved oxygen and nitrogen. Under diesel engine operating conditions, this multi-phase mixture would be highly reactive and could initiate local pyrolysis and/or oxidation reactions. Finally, the dynamical behaviour of the diesel fuel in the nozzle holes would support the admission of external hot combustion gases into the nozzle holes, establishing the conditions for oxidation/pyrolysis reactions with surrounding liquid fuel films

Getting creative in everyday life: Investigating arts and crafts hobbyists' information behavior

While there has been increasing interest in how creative professionals find information to drive creative outputs, previous information behavior research has largely ignored how arts and crafts hobbyists look for information sources in their everyday lives. To fill this literature gap, we conducted interviews and observations with arts and crafts hobbyists to find out how they conceive potential DIY projects. The findings highlight three themes: the dearth of human sources, the prevalence of domain-specific information, and the use of self-curated information. In addition to empirical results, this work also broadens the understanding of information behavior in an arts and crafts context by studying populations beyond professional artists

Dynamics of the spin-boson model with a structured environment

We investigate the dynamics of the spin-boson model when the spectral density of the boson bath shows a resonance at a characteristic frequency $\Omega$ but behaves Ohmically at small frequencies. The time evolution of an initial state is determined by making use of the mapping onto a system composed of a quantum mechanical two-state system (TSS) which is coupled to a harmonic oscillator (HO) with frequency $\Omega$. The HO itself is coupled to an Ohmic environment. The dynamics is calculated by employing the numerically exact quasiadiabatic path-integral propagator technique. We find significant new properties compared to the Ohmic spin-boson model. By reducing the TSS-HO system in the dressed states picture to a three-level system for the special case at resonance, we calculate the dephasing rates for the TSS analytically. Finally, we apply our model to experimentally realized superconducting flux qubits coupled to an underdamped dc-SQUID detector.Comment: 26 pages, 11 figures, Chemical Physics Special Issue on the Spin-Boson Problem, ed. by H. Grabert and A. Nitzan, in pres

After serendipity strikes: Creating value from encountered information

Existing research into serendipitous information encountering has focused on how people stumble upon information, rather than how they create value from the information encountered. This online diary study with follow-up interviews provides an enriched understanding of the subjective value of information encounters and the motivators, barriers and actions involved in creating value from them. We leverage our findings to generate design suggestions for digital information tools aimed at assisting in creating value from encountered information

Finite quantum environments as thermostats: an analysis based on the Hilbert space average method

We consider discrete quantum systems coupled to finite environments which may possibly consist of only one particle in contrast to the standard baths which usually consist of continua of oscillators, spins, etc. We find that such finite environments may, nevertheless, act as thermostats, i.e., equilibrate the system though not necessarily in the way predicted by standard open system techniques. Thus, we apply a novel technique called the Hilbert space Average Method (HAM) and verify its results numerically.Comment: 12 pages, 10 figure

Iterative algorithm versus analytic solutions of the parametrically driven dissipative quantum harmonic oscillator

We consider the Brownian motion of a quantum mechanical particle in a one-dimensional parabolic potential with periodically modulated curvature under the influence of a thermal heat bath. Analytic expressions for the time-dependent position and momentum variances are compared with results of an iterative algorithm, the so-called quasiadiabatic propagator path integral algorithm (QUAPI). We obtain good agreement over an extended range of parameters for this spatially continuous quantum system. These findings indicate the reliability of the algorithm also in cases for which analytic results may not be available a priori.Comment: 15 pages including 11 figures, one reference added, minor typos correcte