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We develop a six-compartment model consisting of phosphorus, detritus, phytoplankton, zooplankton, planktonivorous fish and pisciphagous fish. In this model, we study the implications that the body sizes of phytoplankton and zooplankton have on the system dynamics. We use ascendency as a goal function or indicator of system performance. Ascendency quantifies growth and development of an ecosystem as a product of total system throughflow and the mutual information inherent in the pattern of internal system flows. Different physiological rate parameters of phytoplankton and zooplankton are assessed by means of allometric relationships applied to their body sizes. We let the phytoplankton body size range from 10 μm³ to 10⁷ μm³ and the zooplankton body size range from 10 μm³ to 10⁴ μm³ in volume. We also investigate the effects of phosphorus input conditions, corresponding to oligotrophic, mesotrophic and eutrophic systems on system dynamics. Ascendency (to be maximized over phytoplankton and zooplankton sizes) was computed after the system had reached a steady state. Since it always was a seasonal cycle, and the ascendency followed this behavior, we averaged the ascendency over 365 successive days (duration of one year) in the oscillatory phase. Under all types of nutrient conditions, the smallest phytoplankton size yielded the maximal values of the ascendency, while the corresponding zooplankton size varied. Under oligotrophic conditions, a phytoplankton size of 10 μm³ combined with a zooplankton size of 10^1.25 μm³ to give the maximum value of the ascendency. Under mesotrophic and eutrophic conditions, maxima were obtained for zooplankton sizes 10^2.26 μm³ and 10^3.20 μm³, respectively.

Vibrio vulnificus may cause severe soft tissue infections of the upper extremity. This pathogen usually gains access to soft tissues either by direct inoculation through a penetrating injury by an infected marine animal or by exposing abraded skin to contaminated water. We report five patients with Vibrio vulnificus hand infections following superficial hand injuries incurred within 24 hours after uneventful handling of fish. This clinical observation, together with the fact that the physiologic characteristics of human sweat simulate the natural environment of the Vibrio vulnificus, support the assumption that human skin may serve as a reservoir for Vibrios. The anamnesis in patients presenting with hand infection should essentially include an inquiry regarding recent, albeit uneventful, fish handling.

Fat Reducing Fruit.

Multivalent Anti-Bacterial Vaccines Available for Fish.

Free Trade Zones in Taiwan by 2008.

Moth Released to Control Mimosa Spread.

Investing in Technology for Water Sustainability.

Water Policy Response to Water Scarcity and Future Climate Change Impacts.

Recirculation Aquaculture Systems (RAS): An Opportunity for the SE Asian Aquaculture Industry.

Nocardia seriolae infections pose a significant economic threat to Taiwan’s aquaculture. It is therefore important to find the most effective antibiotics to treat these infections. However, a standardized method to determine the most suitable minimal inhibitory concentration (MIC) values of antibiotics againist N. seriolae has not yet to be agreed. This study tested 7 antibiotics on 80 N. seriolae isolates, using the disk diffusion and broth diffusion methods described by Alderman and Smith to find their MIC values. All the isolates were found to be sensitive to trimethoprim and oxytetracycline, which showed that these drugs could treat nocardiosis in fish. Among the seven drugs tested, amoxicillin was found to have very high MIC90 value, which was $>$128$\mu$g/mL and flumequine had the highest MIC50 value, which was 51.06$\mu$g/mL. MIC50 and MIC90 values were very low in erythromycin, which was $<$0.12 and 0.41$\mu$g/mL, respectively. N. seriolae isolates were sensitive to florfenicol (98.8%), erythromycin (97.5%), thiamphenicol (68.8%), amoxicillin (8.8%) and flumequin (0%), separately. This study has found that oxytetracycline, trimethoprim or erythromycin, florfenicol, thiamphenicol are good drugs to treat N. seriolae infection in fish.

Production of energy is a foundation of life. The metabolic rate of organisms (amount of energy produced per unit time) generally increases slower than organisms’ mass, which has important implications for life organization. This phenomenon, when considered across different taxa, is called interspecific allometric scaling. Its origin has puzzled scientists for many decades, and still is considered unknown. In this paper, we posit that natural selection, as determined by evolutionary pressures, leads to distribution of resources, and accordingly energy, within a food chain, which is optimal from the perspective of stability of the food chain, when each species has sufficient amount of resources for continuous reproduction, but not too much to jeopardize existence of other species. Metabolic allometric scaling (MAS) is then a quantitative representation of this optimal distribution. Taking locomotion and the primary mechanism for distribution of energy, we developed a biomechanical model to find energy expenditures, considering limb length, skeleton mass and speed. Using the interspecific allometric exponents for these three measures and substituting them into the locomotion-derived model for energy expenditure, we calculated allometric exponents for mammals, reptiles, fish, and birds, and compared these values with allometric exponents derived from experimental observations. The calculated allometric exponents were nearly identical to experimentally observed exponents for mammals, and very close for fish, reptiles and the basal metabolic rate (BMR) of birds. The main result of the study is that the MAS is a function of a mechanism of optimal energy distribution between the species of a food chain. This optimized sharing of common resources provides stability of a food chain for a given habitat and is guided by evolutionary pressures and natural selection.

This paper provides an overview of current knowledge regarding the aquatic effects of nanomaterials. Aquatic receptors can potentially be exposed to nanoparticles through ingestion, movement across gills, passive transport, and cellular absorption. Our review indicates that the toxicological research on nanomaterials is still relatively narrow. The present research has been targeted primarily at understanding potential effects to humans, and relatively few ecotoxicity studies have been conducted; however, new research is evolving rapidly. The studies that are currently available focus on metal oxide particles, carbon nanotubes, and fullerenes. Aquatic tests have examined the uptake of these nanoparticles by fish and filter feeders, and have provided evidence of toxicity or behavioral changes. Some of these studies conclude that nanoparticles can be taken up by or produce effects in biota, and that dose-response relationships and patterns of relative toxicity among types of particles are emerging. Caution should be used in designing and interpreting studies on nanoparticles, because factors such as the particle medium preparation method, the presence of other chemicals, and particle behavior such as agglomeration can influence exposure and aquatic toxicity. Ultimately, the objectives of this review are to expand our knowledge of the effects of nanomaterials on ecological processes and aquatic receptor populations, as well as help guide future research.

In this study, the development of a graphite paste electrode (GPE) modified by copper oxide nanoparticles (CuO@GP) to be used as a practical and economical sensor for the electrochemical sensing of malachite green (MG) has been elucidated. The sol–gel technique was applied for the synthesis of CuO nanoparticles (NPS) from copper chloride (CuCl${}_2)$, where the surfactant cetylpyridinium chloride (C${}_{21}$H${}_{38}$NCl) played the role of a capping agent. The synthesized CuO NPS were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). A bare GPE was modified using these CuO NPS and thus developed; the new electrode was used as a working electrode (WE) in a 3-electrode system for studying the cyclic voltammetry (CV) and differential pulse voltammetry (DPV) responses of MG. Phosphate buffered saline (PBS) with a pH value of 6 was used as the optimum buffer. Using DPV, a widely linear operational range of 1–1000 $\mu$M was obtained with a detection limit of 0.18 $\mu$M. This CuO@GP provided excellent repeatability, reproducibility and prolonged stability for the MG molecule. For the selectivity study, various common interfering agents were used to observe MG’s corresponding peak current variation. Moreover, this electrode demonstrated a successful application for detecting MG in pond water and fish flesh. This method is effective for similar other applications.

In this chapter, we update our recent two-step model of the evolution of primary, phenomenal, sensory consciousness in vertebrate animals, a model based on neurobiological naturalism (see Chapter 1). The model proposes that this consciousness first appeared in the earliest vertebrates from mental reconstructions at the top of topographically organized neural hierarchies in the optic tectum of the midbrain (for vision and other senses) and in the pallium of the forebrain (for smell perception). Here, we add more information about the optic tectum that relates to such image reconstruction. Second, sensory consciousness leaped forward independently in the first mammals and then in the first birds, to be generated by an expanding dorsal pallium (cerebral cortex). We propose more reasons for this second step, all related to the favorable location of the dorsal pallium at the nexus of all kinds of sensory input, already highly processed, and near the hippocampus so that conscious experiences could be enriched by memories.