Vertical oscillations of the thermocline caused by internal waves modify coldwater pelagic fish distribution: Results from a large stratified lake

Fishes typically occupy a species-specific temperature range, with their occupied depth being related to the lake’s temperature profile. When a fish’s preferred temperature range coincides with the thermocline, the location of their preferred thermal habitat is influenced by the rise and fall of internal waves, leading to possible changes in fish depth. These internal waves are common in large, stratified lakes, yet we do not know how they affect the spatial distribution and behavior of freshwater fishes. We conducted nighttime hydroacoustic surveys in a large, deep embayment of a large thermally stratified lake to observe whether pelagic fish respond to vertical oscillations of the thermocline caused by internal waves. The coldwater pelagic fish in our study (primarily cisco, Coregonus artedi) typically occupied a narrow vertical band approximately 5–8 m thick and temperatures between 10.8 ± 0.8–13.6 ± 1.6 °C (fishes sized 106–500 mm), just below the thermocline (centered around 15–17 °C). Importantly, the upper bound of fish depth varied in response to vertical thermocline movements associated with internal waves, suggesting fish respond to changes in their physical environment on timescales commensurate with basin-scale internal wave periods (hours to days), to remain within their preferred thermal habitat. Dissolved-oxygen levels were typically above avoidance thresholds of these fish, thus not likely exerting a strong influence on fish location. Our findings emphasize the need to account for internal waves when designing hydroacoustic and netting surveys, as thermocline movements can influence where fish are located.     

Life history of Plodia interpunctella Hübner on sunflower seeds: Effects of seed qualitative traits and the initial seed damage

Sunflower seeds are regularly infested by Plodia interpunctella during storage. Although this pest prefers damaged seeds, in practice it can infest undamaged seeds as well. This research assessed the influence of the sunflower seed type (oil, protein for human consumption and bird-feed) and the initial seed damage during post-harvest processing (dehulled kernels, 10, 20, 30% of damaged seeds and undamaged seeds) on development of P. interpunctella (larval mortality, larval development, mean developmental duration, adult emergence and fecundity). Biochemical analysis of seeds, kernels and hulls detected the highest content of phenols in the seed and hull and tocopherols in the kernel of the oil type hybrid. The antioxidative activity was the highest in the seed, kernel and hull of the protein type for bird feed. The shortest development (39.5 days) and the highest fecundity (91.3) were on the oil type seeds, while the longest development (42.1 days) and the lowest fecundity (68.1) were on the seeds of the protein type for bird feed. The highest mortality of larvae was on the undamaged seeds of the protein type for bird feed and human consumption (21.3% and 14.0%, respectively). The type of sunflower and the level of initial damage affected larval mortality, developmental duration and fecundity. The mean developmental duration and the number of emerged adults were dependent only on the initial seed damage. Principal component analysis detected strong positive correlation between mortality and development with the tocopherol content on the undamaged seeds while fecundity was associated with the state of kernel and the amount of tannins, proteins and oil content in the seed. The undamaged seeds of the protein type for the bird feed were the least suitable for the development of this pest, while the oil type kernels were the most suitable.     

Climate proofing island energy infrastructure systems: Framing resilience based policy interventions

One of the most discernible impacts of climate change is the increasing severity and unpredictability of extreme weather conditions. Small island developing states are particularly vulnerable to these conditions, with one of the impacts being on energy supplies due to damaging energy infrastructure, resulting in power outages and economic losses. Drawing on resilience theory to frame the discourse, we present an updated overview of how island energy infrastructures have been and continue to be negatively impacted. This same framework also provides a lens through which we identify the challenges involved in recovery, rebuilding and returning energy security in these contexts.     

Consumers’ willingness to pay for upcycled foods

Research on food waste reduction suggests that solutions aimed at reducing waste early in the consumption cycle are the most impactful. Based on this premise, food research labs and food manufacturers have started creating and selling foods made from food ingredients that are generally discarded. Such foods, termed upcycled foods, are safe for human consumption and provide a promising solution to reduce food waste. However, the commercial success of this new category of foods will depend on consumers’ acceptance. This research examines a key indicator of acceptance – consumers’ willingness to pay. We find that although consumers are willing to pay less for upcycled foods compared to conventional alternatives, messaging increases consumers’ willingness to pay. Specifically, we find that rational messaging is more effective than emotional messaging. Overall, our findings suggest that upcycled foods may command good acceptance among consumers.     

Thermogravimetric kinetics on catalytic combustion of bituminous coal

The catalytic combustion and non-isothermal kinetics of bituminous coal by CeO₂, Fe₂O₃, and NiO were investigated. The exothermic characteristics during catalytic combustion of bituminous coal were determined. Based on the Coats-Redfern method by introducing the function of kinetics mechanisms, the activation energies and pre-exponential factors of catalytic combustion of bituminous coal were estimated iteratively by regression. It is found that the catalysts promoted the transport of oxygen to the coal or char surface and effectively improved the combustion characteristics of bituminous coal. Under the same experimental conditions, the exothermic values were significantly increased and the catalysts of composite oxides exhibited higher exothermic values than pure metal oxide catalysts. The metal oxides significantly reduced the activation energies of bituminous coal combustion. SEM analysis presented that combustion residues became more porous with the addition of the catalyst.     

Virucidal effect of high power ultrasound combined with a chemical sanitizer containing peroxyacetic acid for water reconditioning in the fresh-cut industry

The use of chlorine-based sanitizers is widespread throughout the fresh produce industry in the process water to maintain microbial safety of produce, avoid cross-contamination and recycle water. In this study, alternative disinfection technologies were investigated due to the negative reports showing chlorine instability in the presence of organic matter and the undesirable by-product residues. Tsunami^® (15.2% peroxyacetic acid and 11.2% hydrogen peroxide) and high-power ultrasound (HPU, 0.56 kW/l, 20 kHz), alone or in combination, were evaluated in lettuce process water analyzing their ability to reduce MNV during either produce washing or water recycling. PAA concentrations of 6.4, 12.8 and 16 mg/l as well as HPU were insufficient for application in the produce washing tank where a rapid MNV inactivation is required. In contrast, a complete rapid inactivation of MNV (7.4 log TCID₅₀) was recorded when 80 mg/l of PAA was used. For recycled water reconditioning, HPU was applied and no virus reduction was observed. Two PAA concentrations (6.4 and 12.8 mg/l) that can be found in the recycled water were also tested. The MNV inactivation was faster at 12.8 mg/l than at 6.4 mg/l of PAA with 2.6 and 2 log reductions after 20 min contact. One additional log reduction was achieved 20 and 40 min later, respectively. MNV inactivation fitted the Bipashic model well. A contact time of 95 and 115 min would be required to obtain the complete elimination of MNV (4.4 log TCID₅₀) by 6.4 and 12.8 mg/l of PAA. PAA efficacy was not enhanced by the combination with HPU in contrast to the inactivation of pathogenic bacteria tested in other studies. This indicates that viruses are more resistant to this hurdle technology than pathogenic bacteria such as Escherichia coli O157:H7, Salmonella and other HPU conditions such as higher frequencies and combination of HPU with other physical treatments need to be explored.     

Enhanced bioactivity of Zanthoxylum schinifolium fermented extract: Anti-inflammatory,anti-bacterial,and anti-melanogenic activity

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Non-noble metal ultrathin MoS2 nanosheets modified Mn0.2Cd0.8S heterostructures for efficient photocatalytic H2 evolution with visible light irradiation

A series of non-noble metal ultrathin MoS₂ nanosheets modified Mn_0.2Cd_0.8S heterostructured composites were prepared by an ultrasonic assisted hydrothermal synthesis process. Comparing with the pristine Mn_0.2Cd_0.8S composite, the obtained ultrathin MoS₂/Mn_0.2Cd_0.8S composites exhibited a significantly improved photocatalytic activity for hydrogen evolution from water with visible light response. The optimized photocatalytic activity toward MoS₂/Mn_0.2Cd_0.8S composite is around 8 times of the pristine Mn_0.2Cd_0.8S composite. Moreover, the ultrathin MoS₂/Mn_0.2Cd_0.8S composites displayed good photocatalytic stability in the course of photochemical reaction. The excellent photocatalytic activity of the ultrathin MoS₂/Mn_0.2Cd_0.8S composites might be attributed to the formed heterojunctions in composites itself and the sufficient active edge sites in MoS₂ phase. A possible photocatalytic mechanism was tentatively proposed. Considering its excellent photocatalytic activity and good photochemical stability, the obtained ultrathin MoS₂/Mn_0.2Cd_0.8S composite has potential application in photocatalytic hydrogen evolution from water by using solar energy.