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Efficient allocation of energy resources to key physiological functions allows living organisms to grow and thrive in diverse environments and adapt to a wide range of perturbations. To quantitatively understand how unicellular organisms utilize their energy resources in response to changes in growth environment, we introduce a theory of dynamic energy allocation that describes cellular growth dynamics by partitioning metabolizable energy into key physiological functions: growth, division, cell shape regulation, energy storage and loss through dissipation. By optimizing the energy flux for growth, we develop the equations governing the time evolution of cell morphology and growth rate in diverse environments. The resulting model accurately captures experimentally observed dependencies of bacterial cell size on growth rate, superlinear scaling of metabolic rate with cell size and predicts nutrient-dependent trade-offs between energy expended for growth, division and shape maintenance. By calibrating model parameters with experimental data for the model organism Escherichia coli, our model describes bacterial growth control in dynamic conditions, particularly during nutrient shifts and osmotic shocks. Integrating both the mechanical properties of the cell and underlying biochemical regulation, our model predicts the driving factors behind a wide range of observed morphological and growth phenomena with minimal added complexity. [ABSTRACT FROM AUTHOR]

In recent years, population outbreaks of the annelid Hermodice carunculata (Polychaeta, Amphinomidae) are recurrently detected along the coastal zone of the Salento peninsula (Southern Italy), with impacts on marine benthic ecosystems. Annelida are renowned for their remarkable regeneration potential, enabling them to reform lost body parts. A handful of studies have reported posterior regeneration of H. carunculata, but anterior regeneration has not been fully explored. In this study, we investigated the capacity of H. carunculata collected in shallow coastal areas (Ionian Sea, 40°08'26.9" N 17°58'44.1" E) to regenerate anterior body parts under different temperature conditions (22 and 14 °C) and considering two different body sizes (∼ 4 g and 25 g). In addition, histological analysis and lipid analyses were carried out to detect changes in the reproductive cycle and lipid storage during ongoing regeneration. The results suggest that small and large-sized specimens of H. carunculata can regenerate efficiently anterior body parts in 12–20 weeks post amputation when kept at 22 °C. Small-sized worms kept at 14 °C regenerated slower but died in 24 weeks post amputation before regenerating a mouth, while large-sized worms kept at 14 °C were affected by a 100% mortality during blastema formation. In addition, lipid extraction analyses show that H. carunculata can regenerate during extended periods of starvation by de novo synthesizing lipid reserves and regeneration in H. carunculata does not negatively impact the reproductive cycle, as gametogenesis occurs also during the regenerative processes. [ABSTRACT FROM AUTHOR]

The rise of electric vehicles (EVs) has significantly transformed transportation, offering environmental advantages by curbing greenhouse gas emissions and fossil fuel dependency. However, their increasing adoption poses challenges for power systems, especially distribution systems, due to the direct connection of EVs with them. It requires robust infrastructure development, smart grid integration, and effective charging solutions to mitigate issues like overloading and peak demand to ensure grid stability, reliability, and sustainability. To prevent local equipment overloading during peak load intervals, the management of EV charging demand is carried out in this study, considering both the time to deadline and the energy demand of EVs. Initially, EVs are prioritized based on these two factors (time and energy)—those with shorter deadlines and lower energy demands receive higher rankings. This prioritization aims to maximize the number of EVs with their energy demands met. Subsequently, energy allocation to EVs is determined by their rankings while adhering to the transformer's capacity limits. The process begins with the highest-ranked EV and continues until the transformer nears its limit. To this end, an index is proposed to evaluate the performance of the proposed method in terms of unserved EVs during various peak load intervals. Comparative analysis against the earliest deadline first approach demonstrates the superior ability of the proposed method to fulfill the energy demand of a larger number of EVs. By ensuring sustainable energy management, the proposed method supports the widespread adoption of EVs and the transition to a cleaner, more sustainable transportation system. Comparative analysis shows that the proposed method fulfills the energy needs of up to 33% more EVs compared to the earliest deadline method, highlighting its superior performance in managing network loads. [ABSTRACT FROM AUTHOR]

Non-lethal injury in animals is both common and costly. The cost of regenerating autotomized limbs may leave less energy available for processes such as reproduction and growth, leading to trade-offs. Such trade-offs are context-dependent, and an individual’s energy allocation strategies may vary widely based on its condition and the environment. However, many traditional bioenergetics models have relied on fixed energy allocation rules, such as the -rule of dynamic energy budget theory, which assumes a fixed proportion (κ) of assimilated energy is always allocated to growth and maintenance. To determine whether incorporating optimality approaches into bioenergetics models improves the ability to predict energy allocation, we developed a dynamic state variable model that identifies optimal limb regeneration strategies in a model system, the Asian shore crab Hemigrapsus sanguineus. Our model predictions align with known patterns for this species, including increased regeneration effort with injury severity, a shift from reproduction to growth as consumption amount increases, and an increase in regeneration effort as regeneration progresses. Lastly, Monte Carlo simulations of individuals from a previous experiment demonstrate that flexible energy allocation successfully predicts reproductive effort, suggesting that this approach may improve the accuracy of bioenergetics modeling.

BACKGROUND: Migration is a strategy that shifts insects to more favorable habitats in response to deteriorating local environmental conditions. The ecological factors that govern insect migration are poorly understood for many species. Plutella xylostella causes great losses in Brassica vegetable and oilseed crops, and undergoes mass migration. However, the physiological and behavioral basis for distinguishing migratory individuals and the factors driving its migration remain unclear. RESULTS: Daily light trap catches conducted from April to July in a field population of P. xylostella in central China revealed a sharp decline in abundance from late‐May. Analysis of ovarian development levels showed that the proportion of sexually immature females gradually increased, while the mating rate decreased, indicating that generations occurring in May mainly resulted from local breeding and that emigration began in late‐May. Physiological and behavioral analyses revealed that emigrant populations had a higher take‐off proportion, stronger flight capacity and greater energy reserves of triglyceride compared to residents. Furthermore, a gradual increase in temperature from 24 °C to >30 °C during larval development resulted in a significant delay in oogenesis and increased take‐off propensity of adults compared with the control treatment reared at a constant temperature of 24 °C. CONCLUSION: Our results provide the physiological and behavioral factors that underpin mass migration in P. xylostella, and demonstrate that exposure to increased temperature increases their migration propensity at the cost of reproductive output. This study sheds light on understanding the factors that influence population dynamics, migratory propensity and reproductive tradeoffs in migratory insects. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Metabolic rates, including standard (SMR) and maximum (MMR) metabolic rate have often been linked with life-history strategies. Variation in context- and tissue-level metabolism underlying SMR and MMR may thus provide a physiological basis for life-history variation. This raises a hypothesis that tissue-specific metabolism covaries with whole-animal metabolic rates and is genetically linked to life history. In Atlantic salmon (Salmo salar), variation in two loci, vgll3 and six6, affects life history via age-at-maturity as well as MMR. Here, using individuals with known SMR and MMR with different vgll3 and six6 genotype combinations, we measured proxies of mitochondrial density and anaerobic metabolism, i.e. maximal activities of the mitochondrial citrate synthase (CS) and lactate dehydrogenase (LDH) enzymes, in four tissues (heart, intestine, liver, white muscle) across low- and high-food regimes. We found enzymatic activities were related to metabolic rates, mainly SMR, in the intestine and heart. Individual loci were not associated with the enzymatic activities, but we found epistatic effects and genotype-by-environment interactions in CS activity in the heart and epistasis in LDH activity in the intestine. These effects suggest that mitochondrial density and anaerobic capacity in the heart and intestine may partly mediate variation in metabolic rates and life history via age-at-maturity. This article is part of the theme issue 'The evolutionary significance of variation in metabolic rates'. [ABSTRACT FROM AUTHOR]

Smart cities can be viewed as expansive systems that optimize operational quality and deliver a range of services, particularly in the realm of energy management. Identifying energy zones within smart cities marks an initial step towards ensuring equitable energy distribution driven by factors beyond energy considerations. This study introduces a socially oriented methodology for energy allocation during emergencies, implemented at the zone level to address justice concerns. The proposed method integrates a fuzzy leaky bucket model with an energy virtual buffer, leveraging extensive data from diverse city zones to allocate energy resources during emergent situations. By employing fuzzy sets and rules, the leaky bucket mechanism distributes buffered energy to zones, aiming to maximize energy utilization while promoting social justice principles. Evaluation of the approach utilizes consumption data from simulated smart city zones during energy-constrained emergencies, comparing it against a uniform allocation method. Results demonstrate the socially equitable allocation facilitated by the proposed methodology. [ABSTRACT FROM AUTHOR]

Energy consumption remains an open challenge in aerial systems such as CubeSats and therefore optimization of its allocation is a top priority for maximizing operational capacity. Our research review reveals a plethora of approaches for optimization of energy allocation and all achieving varying degrees of success and not without any compromises. In this paper, we exploit the use of serious gaming in a novel energy allocation algorithm that aims at minimizing energy consumption to maximize the utilities of both CubeSats and terrestrial sensors. To demonstrate this, we use Stackelberg for serious gaming and standalone topology for CubeSat configuration. The experimental results show that the use of a Stackelberg game approach for optimization has led to reduction in the required transmission energy in sensors, an improved link performance between the CubeSat and ground sensors, and an increase in network lifetime and performance without resorting into sensor power enhancements or other external power sources. The overall average operational capacity improvement predictions range between 22 to 27% across all performance indicators of energy efficiency across RF chains of link budgets. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between environmental regulation and total factor carbon productivity in China's industrial sectors. Using panel data analysis from 2000 to 2016, we find that environmental regulations significantly enhance carbon productivity. We also examine the mediating effect of environmental regulation and analyze the dynamic effects using a threshold effect model. The results reveal a non-linear relationship, where stricter regulations may increase carbon emissions beyond a certain threshold. The study emphasizes the importance of energy allocation and technology development in shaping carbon productivity outcomes. Promoting innovation, developing a clean energy system, and implementing effective environmental regulations are crucial for improving total factor carbon productivity and achieving sustainable economic growth. [ABSTRACT FROM AUTHOR]

Phytoplanktonic communities have been moulded from a higher level in the food web by zooplankton predation. Diatoms, which are the major primary producers in present day oceans, have evolved many strategies to thrive in the presence of copepods, their predators. Chemical signals are released in the aquatic environment by microarthropods and elicit morphological, behavioural and/or physiological modifications in diatom cells which allow them to cope with predators. Other than the most studied effects of copepod signals on the release of toxins by diatoms, the role of chemical cues on growth and biology of non-toxic diatoms has been little investigated, although it may broaden our knowledge of co-evolutive physiological mechanisms. To examine the response of diatoms to copepod-derived signals, Phaeodactylum tricornutum, Chaetoceros muelleri and Cylindrotheca fusiformis (Bacillariophyceae) were grown in the presence of copepod cues. Physiological modifications occurred and differed in sign and magnitude between species: i) in P. tricornutum cell density was higher, and dry weight lower, suggesting energy allocation into cell division at the expense of lipid and protein quotas; ii) C. muelleri showed a very homeostatic behaviour; and iii) in C. fusiformis cell density was lower and lipid content higher, showing energy allocation into lipids, which likely act as deterrent to feeders. Copepod cues are here suggested to have ruled diatom species composition in the ocean by affecting species-specific growth performance and the energy allocation into macromolecules. [ABSTRACT FROM AUTHOR]

For temperate-zone mammals, seasonal changes in weather and food availability often govern energy allocation. In addition, energy allocation strategies usually differ between males and females. Bats are an interesting group in which to evaluate energetic trade-offs as they are highly mobile and lead energetically demanding lives in habitats across a variety of seasonally variable climates. We evaluated year-round changes in body mass and fuel load for three species of bats in northern California: Silver-haired Bat (Lasionycteris noctivagans), California Myotis (Myotis californicus), and Yuma Myotis (Myotis yumanensis). Silver-haired bats are considered migratory species with females likely migrating farther than males. The two species of myotis are considered residents. Body mass of all species peaked in late autumn and was at a minimum during spring. We calculated a fuel load index to normalize size difference between species and sexes. We used sex- and season-specific multiple linear regression models to evaluate rates of change in seasonal fuel loading. Rates of change in fuel load did not differ among species or sexes except for male silver-haired bats that increased fuel loads rapidly during summer. Interspecific comparisons provided valuable insights into the energy allocation and overwintering strategies of these species and are an important initial step toward understanding their ecology over the full annual cycle. [ABSTRACT FROM AUTHOR]

There is growing empirical evidence that animal hosts actively control the density of their mutualistic symbionts according to their requirements. Such active regulation can be facilitated by compartmentalization of symbionts within host tissues, which confers a high degree of control of the symbiosis to the host. Here, we build a general theoretical framework to predict the underlying ecological drivers and evolutionary consequences of host‐controlled endosymbiont density regulation for a mutually obligate association between a host and a compartmentalized, vertically transmitted symbiont. Building on the assumption that the costs and benefits of hosting a symbiont population increase with symbiont density, we use state‐dependent dynamic programming to determine an optimal strategy for the host, i.e., that which maximizes host fitness, when regulating the density of symbionts. Simulations of active host‐controlled regulation governed by the optimal strategy predict that the density of the symbiont should converge to a constant level during host development, and following perturbation. However, a similar trend also emerges from alternative strategies of symbiont regulation. The strategy which maximizes host fitness also promotes symbiont fitness compared to alternative strategies, suggesting that active host‐controlled regulation of symbiont density could be adaptive for the symbiont as well as the host. Adaptation of the framework allowed the dynamics of symbiont density to be predicted for other host‐symbiont ecologies, such as for non‐essential symbionts, demonstrating the versatility of this modelling approach. [ABSTRACT FROM AUTHOR]

Insular populations of mammals have been shown to undergo drastic morphological changes relative to mainland counterparts, and these adaptations can provide insight into the evolutionary effects of predation and competition. Selection has been shown to favor more energetically efficient body plans in insular mammals, even when this entails the reduction of anti-predator defenses, but few studies have focused on morphological effects within the same species. Previous research has established that insular large mammals tend to reduce in body size, and that size reduction may not scale isometrically across all body parts. The brain has been a particular subject of interest due to its high energy requirements. Here, we report that an extant, dwarfed island population of black-tailed deer (Odocoileus hemionus columbianus) exhibits significantly reduced brain mass relative to body mass in comparison to their mainland conspecifics, with brain mass 4.9% smaller in the island population for a given body mass. Further, in the dwarfed population, orbital area was 4.1% smaller for a given body mass, but this reduction was not significant. Foramina magna reduced isometrically. In resource-limited insular environments, negative allometry of the brain is consistent with predictions of reduced investment in energetically costly organs. This study is, to our knowledge, the first to examine the morphological effects of insularity on brain size in two conspecific populations, and these findings suggest that selection toward reduced brain size may act relatively quickly after isolation. [ABSTRACT FROM AUTHOR]

Previous studies have provided evidence of a reduced aerobic metabolic capacity, both at the cellular (metabolic enzyme activity) and the whole organism (aerobic scope) level in juvenile triploid white sturgeon, compared to diploid siblings. The downstream costs of this reduced metabolic capacity are still unclear, yet a lower aerobic scope suggests triploid white sturgeon likely have less energy to allocate to biological processes like growth and development. We conducted a 15-week growth trial to assess energy allocation to somatic growth in 2-month-old diploid and triploid white sturgeon. Spontaneous swimming activity, hepatosomatic index, condition factor, and deformities were also measured throughout the growth trial as indices of energy allocation to activity and fish condition. In general, our results indicate that triploid white sturgeon may have less energy available for processes beyond basal maintenance. This could be linked to a reduced overall performance as evidenced by lower weights and more deformities when compared with their diploid counterparts. However, many indices were still mostly unaffected by triploidy (condition factor, hepatosomatic index, and swimming activity). Whether this lower growth performance seen in juvenile triploid white sturgeon continues through sub-adulthood, puberty and final maturation requires further long-term studies.

Abstract By transferring power-hungry huge data centers to lightweight Internet of Things (IoT) mobile devices, mobile edge computing (MEC) has completely changed the IoT. For MEC, to optimize economic gains and motivate profit-oriented entities, the joint resource allocation and network economics problem must be solved, and the joint issue is limited by local constraints, namely, the edge server only serves multiple nearby mobile devices, which is restricted by its available energy. The article studies the jointly issue of network economics and energy allocation in MEC, where mobile device apply for offloading at a purported bid and an edge server supplies its restricted serving at an asking price. In particular, this paper puts forward two dynamic pricing double auction strategies in the MEC system, i.e., a double auction according to the break-even mechanism (DABM) and a more practical double auction based on dynamic pricing mechanism (DADPM) to decide the matching between mobile devices and edge servers, and the pricing strategy for high-priced economic profit in the case of local restricts. Theoretical analysis shows that the proposed two algorithms have properties such as budget balance, individual rationality, economic benefit, authenticity. Extensive simulation experiments evaluate the efficiency of the system, and results verify that the proposed two schemes will greatly make better the economic benefits of MEC.

[Objective] Accelerating the construction of low-carbon energy system and efficient industrial system is the key to converting driving force of China’s economic growth and constructing green and low-carbon circular economic development system. [Methods] This paper decomposes the carbon emission effect through the Kaya identity, meanwhile, it takes several policy objectives in the different provinces’ development plans as constraints and uses the multi-objective planning model to analyze the characteristics of the local energy structure, industrial structure, carbon dioxide emissions, etc. [Results] The results show that under the current energy structure and industrial structure, it is difficult to keep a balance between economic growth and energy-conservation and emission-reduction，through interregional energy allocation and industrial transfer, the emission reduction potential is greater under the synergistic optimization strategy, which is 780.829×106 tons; Energy structure, energy intensity, industrial structure and economic development level will significantly affect the carbon dioxide emissions of different provinces and energy intensity is the dominant factor affecting carbon emissions at this stage. The industrial transference has two sides, while adjusting the industrial structure in different regions, industrial transfer may lead to the increase of carbon dioxide emission in the regions where industrial transfer in, attention should be paid to the level raise of carbon dioxide emissions that lead by industry transfer; With sufficient energy allocation and industrial transfer, the GDP of 30 provinces increases significantly, with growth rates of 7.98% on average. Meanwhile, the economic structure of these provinces is further optimized, and the industrial development highlights the regional characteristics, breaking the dilemma of industrial isomorphism between regions to a certain extent. [Conclusion] By considering the carbon emission effect of regional differentiated development strategy under the constraints of multiple objectives. It is confirmed that the synergistic optimization strategy under the constraint of multiple objectives produces less carbon dioxide emissions, while adopting collaborative optimization strategies, carbon dioxide emissions from energy allocation and industrial transfer should be reduced. This paper provides some enlightenment for the construction of green and low-carbon circular economic development system.

The development of new energy industry is an essential guarantee for the sustainable development of society, and big data technology can enable new energy industrialization. Firstly, this paper presents an in-depth analysis and discussion of big data technology in new energy power and energy storage systems. Furthermore, the current status of big data technology application is discussed based on power generation, grid and user side, while future development trends are proposed based on the characteristics of big data technology. Finally, a comprehensive cloud-platform-based new energy power and energy storage system is proposed, which efficiently combines new energy power generation, consumption, and transmission sides to optimize energy allocation and improve energy utilization efficiency. This paper aims to provide certain guidance significance for new energy research and application.

Simple Summary: The phenomenon of food shortage is widespread in spider populations, but the response of Pardosa pseudoannulata to dietary restriction remains unclear. The study aimed to determine (1) whether energy allocation occurs in P. pseudoannulata under dietary restriction by analysing its development and longevity; (2) if there is a trade-off between development, longevity, and nutrient content indicating a trend to energy allocation; (3) how different levels and periods of dietary restriction affect the predatory ability of P. pseudoannulata. The results showed that the continuous dietary restriction has negative impacts on the growth of P. pseudoannulata, and positive impacts on its longevity. When food was severely restricted in the juvenile stage, nutrient contents of the adult spider could return to the same level as the control group, but the predatory ability decreased. These findings suggest a trade-off between growth, longevity, and predatory ability of the P. pseudoannulata under dietary restriction conditions. The phenomenon of food shortage is widespread in spider populations, which has a great impact on their growth, development, and survival. Pardosa pseudoannulata is a dominant spider species in rice fields and has an important controlling effect on rice pests. In this study, three feeding levels were tested at the juvenile stage (H, high feeding; M, medium dietary restriction; L, severe dietary restriction) and two at the adult stage (H and L). A total of six feeding levels were tested to explore the effects of dietary restriction on the development, longevity, nutrient content, and predation by P. pseudoannulata [HH (control group), HL, MH, ML, LH, LL]. The results showed that continuous dietary restriction (ML and LL groups) had negative impacts on the growth of P. pseudoannulata and positive impacts on longevity. Spiderlings suffered from dietary restrictions during the juvenile period, and when the restrictions were removed upon reaching adulthood (MH and LH groups), their lifespan started decreasing whilst their weight began returning to normal. This suggested that there might be a trade-off between the growth and longevity of the spider under dietary restrictions. The study also found that when food was severely restricted in the juvenile stage (LH and LL groups), the nutrient contents of the adult spider could return to the same level as the control group, but the predatory ability decreased. When food was moderately restricted in the juvenile stage (MH and ML groups), the predatory ability of the adult spiders improved, while nutrients of the adult spiders declined. Our results will provide an empirical basis for the protection and effective use of dominant spider species in agricultural fields. [ABSTRACT FROM AUTHOR]

There is concern that microplastics can act as a vector for cadmium (Cd), altering the bioavailability and subsequent toxicity of Cd to ecologically important species such as Daphnia magna. The toxicity of Cd to D. magna has been well described; however, what is not known, and what the present study addresses, was how the addition of polyethylene microplastic altered Cd toxicity. Using high‐throughput feeding assays and size assessments, the present study quantified effects of exposure to Cd, microplastic, or their mixture on daphnids from neonate to adult. Exposure to Cd inhibited feeding efficiency, while exposure to microplastic inhibited growth rates of juveniles. Daphnia magna coexposed to Cd and microplastic showed significant decreases in both feeding and prereproductive growth rate. There were no differences in life‐history traits across any treatments. The alterations of feeding and growth while maintaining reproductive endpoints (time to first brood, reproductive frequency, the number of neonates released at each reproductive event, and the size of neonates produced) might be the result of a shift in energy allocation away from somatic growth, allowing individuals to maintain reproductive output despite lower nutritional reserves. Our findings suggest that cocontamination of microplastic and Cd has additive effects on feeding and growth rates, resulting in a greater energy allocation shift. Environ Toxicol Chem 2023;42:1401–1408. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Numerous green computing applications employ sustainable energy sources to abate redundant energy consumption. Renewable energy sources are vital to improving energy efficiency and should be used optimally. This paper introduces the Energy Proficient Computing Framework (EPCF) in the resource-centric cloud environment. The main objective of the EPCF is to improve the shared efficiency of energy distribution in the computing systems. Renewable energy is distributed among computers according to their running status and the number of calculations available. Traditional k-means clustering separates the states and computations when making this determination. This mapping procedure is repeated throughout the computation until the energy is dispersed without waste. Energy is conserved for the later use if the sources of the leak can be located in advance. As a result, we can conserve and use energy more effectively. In addition, it speeds up calculations and decreases service allocation waiting times. The proposed framework achieves 14.69% less energy cost for the different service al-location rates, 6.34% less energy drain, and 14.4% high efficiency.

Largemouth bass (LMB) production exceeded 0.7 million tons in 2021 and has become one of the most important freshwater aquaculture species in China. The stable and fixed culture cycle led to regular and drastic price fluctuation during the past decade. Strong price fluctuation provides opportunities and challenges for the LMB industry, and out-of-season spawning (OSS) and culture will provide technical support for the opportunities. To induce OSS at a low cost, we established a controllable recirculating system that allows precise thermophotoperiod manipulation. In the system, four experimental groups were assigned, 18NP (18°C overwintering water temperature, natural photoperiod), 18CP (18°C overwintering water temperature, controlled photoperiod), 16CP (16°C overwintering water temperature, controlled photoperiod), and NTNP (natural water temperature and natural photoperiod), to determine the effects of chilling temperature and photoperiod on spawning performance. OSS was observed in all the experimental groups without significant differences, except NTNP. The manipulated broodstock can re-spawn 3 months later in the next spring in advance. Further analysis of the volume percentage of different stages of oocytes provides a base for excellent regression between the volume percentage of the primary growth stage, cortical alveoli stage, vitellogenesis/maturation stage, and gonadal development/maturation. The results suggest that the volume percentage of oocytes is a better indicator of gonadal development and maturation than the gonadosomatic index. We also found that LMB prefers palm fiber as a spawning nest over gravel. The findings of this work provide important technique guidance for practical OSS of the LMB aquaculture industry and standardization of ovary development and maturation in fish with asynchronous developmental oocytes. [ABSTRACT FROM AUTHOR]

By transferring power-hungry huge data centers to lightweight Internet of Things (IoT) mobile devices, mobile edge computing (MEC) has completely changed the IoT. For MEC, to optimize economic gains and motivate profit-oriented entities, the joint resource allocation and network economics problem must be solved, and the joint issue is limited by local constraints, namely, the edge server only serves multiple nearby mobile devices, which is restricted by its available energy. The article studies the jointly issue of network economics and energy allocation in MEC, where mobile device apply for offloading at a purported bid and an edge server supplies its restricted serving at an asking price. In particular, this paper puts forward two dynamic pricing double auction strategies in the MEC system, i.e., a double auction according to the break-even mechanism (DABM) and a more practical double auction based on dynamic pricing mechanism (DADPM) to decide the matching between mobile devices and edge servers, and the pricing strategy for high-priced economic profit in the case of local restricts. Theoretical analysis shows that the proposed two algorithms have properties such as budget balance, individual rationality, economic benefit, authenticity. Extensive simulation experiments evaluate the efficiency of the system, and results verify that the proposed two schemes will greatly make better the economic benefits of MEC. [ABSTRACT FROM AUTHOR]

In female mammals, reproduction requires high‐energy expenditure because of gestation and lactation; therefore, a fitness cost of current reproduction may lead to a decrease in future survival or reproduction. The reproductive cost differs between short‐lived species with a fast life history strategy compared to long‐lived species with a slow life history strategy. We used harvest data on reproduction and body mass from two small‐sized and short‐lived mammals, mountain and European hare (Lepus timidus and Lepus europaeus) to explore the cost of reproduction and determine how the number of newborns produced in the current breeding season affects female body mass at the end of the reproductive season. Within a reproductive season, female hares experienced a reproductive cost: current litter size was negatively affected by the number of newborns produced in the current breeding season until the current litter. In the given reproductive season, females that had had more litters also had the highest reproductive output and had higher body mass at the end of the breeding season. The presence of a reproductive cost and the high reproductive performance of heavier female hares suggest a strategy of reproduction more conservative than expected for a species with a relatively small size and fast life history strategy. Heavier female hares seemed to be able to face the cost of reproduction, produce more offspring and remain larger at the end of the reproductive season: a strategy that is more conservative than risky. We believe female hares adopt, at least in part, a conservative strategy of reproduction characterized by an increased number of litters per season because of the positive fitness payoff gained. [ABSTRACT FROM AUTHOR]

Interspecific competition determines the invasive capability of alien plants. Phytolacca americana, one of the most destructive invasive plants in China, was first discovered and recorded in China in 1935. Since its arrival, the rapid expansion of the species has driven out a native congener, Phytolacca acinosa. In this study, we assessed the competitive interaction of the invasive P. americana the native P. acinosa in a pot experiment at Yunnan University. Our results indicate that P. americana severely inhibits the growth and reproduction of P. acinosa. Furthermore, P. americana demonstrated a superior resistance against both insect predation and bacterial infection. We suggest that this improved tolerance against herbivory and potentional pathogen damage may be a cornerstone to the invasive success of Phytolacca americana. [ABSTRACT FROM AUTHOR]

Two species of semelparity Nypa palm worms can only reproduce once during their lifetime lives sympatrically. This reproductive is a unique strategy for allocating energy and fecundity to maximize fertility and larval survival. Information about energy allocation and fecundity of semelparity Nypa palm worms is not yet available. This study aimed to obtain data on the strategy of two species of sympatric Nypa palm worms related to total energy allocation, fecundity, and larval survival. Energy allocation determining by the proportion between reproductive energy and somatic energy. Fecundity was calculated based on the total number of oocytes obtained from the same individual samples used for energy measurement. Larvae survival was counting the trochophore and 3-setigers larvae resulting from fertilization. Energy allocation, fecundity, and survival were analyzed descriptively. The results showed that both sympatric species allocated energy for reproduction. The fecundity of Namalycastis rhodochorde was higher than that of Namalycastis abiuma, but had lower larval survival than N. abiuma. Fecundity in N. rhodochorde is a strategy to compensate for the low survival rate. Meanwhile, N. abiuma had lower fecundity but had high larval survival. Fecundity and larval survival between the two sympatric Nypa palm worm species differed, but both allocated the same energy. Different larval survival yet similar energy allocation is their strategy to survive in the same environmental conditions. Dua spesies cacing nipah semelparitas yang hanya dapat melakukan reproduksi sekali selama hidupnya ditemukan hidup secara simpatrik. Kemampuan adaptasi ini mengindikasikan adanya strategi yang khas dalam mengalokasikan energi dan fekunditasnya sehingga dapat memaksimalkan fertilitas dan sintasan larva, namun informasi tersebut masih belum tersedia. Tujuan penelitian ini untuk mendapatkan data strategi dua spesies cacing nipah simpatrik terkait dengan alokasi energi total, fekunditas, dan sintasan larva. Alokasi energi dideterminasi dengan menghitung proporsi antara energi reproduksi dan energi somatis. Fekunditas dihitung berdasarkan jumlah total oosit yang didapatkan dari sampel individu yang sama dengan yang digunakan untuk pengukuran energi. Penghitungan sintasan dilakukan dengan menghitung jumlah larva trokofor dan larva 3-setiger hasil fertilisasi. Data alokasi energi, fekunditas, dan sintasan dianalisis secara deskriptif. Hasil penelitian menunjukkan kedua spesies simpatrik mengalokasi energi untuk reproduksi. Fekunditas Namalycastis rhodochorde lebih tinggi dibandingkan Namalycastis abiuma, namun memiliki sintasan larva yang lebih rendah dari N. abiuma. Fekunditas pada N. rhodochorde merupakan startegi untuk mengimbangi rendahnya sintasan. Sementara itu, N. abiuma memiliki fekunditas yang lebih rendah namun memiliki sintasan larva yang tinggi. Fekunditas dan sintasan larva antara kedua spesies cacing nipah simpatrik ditemukan berbeda namun keduanya mengalokasi energi yang sama. Perbedaan fekunditas dan sintasan serta persamaan alokasi energi merupakan strategi spesies simpatrik untuk dapat bertahan hidup pada kondisi lingkungan yang sama.

Research proposes an optimal power distribution approach for application of electric vehicle (EV) with use of hybrid energy storage system (HESS). HESS protection structure includes dual isolated-based soft-switching symmetrical coupling with half-bridge bidirectional converters to the system of battery and supercapacitors (SCs). The bidirectional converter properly controls the charging process of the battery and SC as well. Besides, spiral wound SCs of mesoporous electrode material have been used in EVs. In the drive cycle of EVs, the operation of SC relates to the functionality of the allocated scheme under “peak load transfer” at 2i sc ∼ 3i bat current profile carried out. New energy allocation strategies under SOC control enable SC charging and discharging at peak currents of around 4i bat. The comparison of the mode of the battery system showed that the performance acceleration built under EVs has been improvised at a certain rate of 50% with a loss of energy minimised to 69%. As a result, the technique adapts different load curves, thus enhancing the utilisation of energy with reduced aging of the battery. The simulation results show that the proposed scheme meets the power demand of a typical driving cycle, for testing vehicle performance, and various energy management system have been assessed based on hydrogen consumption, overall efficiency, state of charge of SCs and batteries, stress on hybrid sources, and DC bus stability. The proposed strategy reduces hydrogen consumption by 8.7% compared to other strategies.

Sexual size dimorphism (SSD) is caused by differences in selection pressures and life‐history trade‐offs faced by males and females. Proximate causes of SSD may involve sex‐specific mortality, energy acquisition, and energy expenditure for maintenance, reproductive tissues, and reproductive behavior. Using a quantitative, individual‐based, eco‐genetic model parameterized for North Sea plaice, we explore the importance of these mechanisms for female‐biased SSD, under which males are smaller and reach sexual maturity earlier than females (common among fish, but also arising in arthropods and mammals). We consider two mechanisms potentially serving as ultimate causes: (a) Male investments in male reproductive behavior might evolve to detract energy resources that would otherwise be available for somatic growth, and (b) diminishing returns on male reproductive investments might evolve to reduce energy acquisition. In general, both of these can bring about smaller male body sizes. We report the following findings. First, higher investments in male reproductive behavior alone cannot explain the North Sea plaice SSD. This is because such higher reproductive investments require increased energy acquisition, which would cause a delay in maturation, leading to male‐biased SSD contrary to observations. When accounting for the observed differential (lower) male mortality, maturation is postponed even further, leading to even larger males. Second, diminishing returns on male reproductive investments alone can qualitatively account for the North Sea plaice SSD, even though the quantitative match is imperfect. Third, both mechanisms can be reconciled with, and thus provide a mechanistic basis for, the previously advanced Ghiselin–Reiss hypothesis, according to which smaller males will evolve if their reproductive success is dominated by scramble competition for fertilizing females, as males would consequently invest more in reproduction than growth, potentially implying lower survival rates, and thus relaxing male–male competition. Fourth, a good quantitative fit with the North Sea plaice SSD is achieved by combining both mechanisms while accounting for sex‐specific costs males incur during their spawning season. Fifth, evolution caused by fishing is likely to have modified the North Sea plaice SSD. [ABSTRACT FROM AUTHOR]

Various environmental alterations resulting from the current global change compromise the persistence of species in their habitual environment. To cope with the obvious risk of extinction, plastic responses provide organisms with rapid acclimatization to new environments. The premise of plastic rescue has been theoretically studied from mathematical models in both deterministic and stochastic environments, focusing on analyzing the persistence and stability of the populations. Here, we evaluate this premise in the framework of a consumer-resource interaction considering the energy investment towards reproduction vs. maintenance as a plastic trait according to positive/negative variation of the available resource. A basic consumer-resource mathematical model is formulated based on the principle of biomass conversion that incorporates the energy allocation toward vital functions of the life-cycle of consumer individuals. Our mathematical approach is based on the impulsive differential equations at fixed moments considering two impulsive effects associated with the instants at which consumers obtain environmental information and when energy allocation strategy change occurs. From a preliminary analysis of the non-plastic temporal dynamics, namely when the energy allocation is constant over time and without experiencing changes concerning the variation of resources, both the persistence and stability of the consumer-resource dynamic are dependent on the energy allocation strategies belonging to a set termed stability range. We found that the plastic energy allocation can promote a stable dynamical pattern in the consumer-resource interaction depending on both the magnitude of the energy allocation change and the time lag between environmental sensibility instants and when the expression of the plastic trait occurs. [ABSTRACT FROM AUTHOR]

[Introduction] Improving energy efficiency is an important path to achieve low-carbon energy transition. The development of multi-energy complementary (MEC) projects has great significance to China's energy transition. How to ensure the sustainable development of MEC projects through business model innovation has become a research hotspot. [Method] Based on the different application scenarios of urban functional areas, the corresponding relationships among load types, general energy demand and typical energy allocation were constructed, and the research on project investment mode, operation mode and profit mode was carried out based on the existing power market, demand side response market and carbon emission right market. [Result] Three business models of assets, service and operation of MEC projects adapted to different urban functional areas are proposed, which enhance the feasibility and extensiveness of the business model. [Conclusion] The research provides a reference for the planning and configuration of MEC projects in different scenarios and comprehensively expands the market types and profit sources that MEC projects can participate in, providing an important reference for the sustainable development of the project.

The mass mortality of Pacific oyster Crassostrea gigas has become a severe ecological and economic concern to Chinese aquaculture, which is proposed to be linked to the phytoplankton community in the farming waters. In the present study, both field and laboratory experiments were conducted to identify the phytoplankton taxa associated with oyster mortality and explore the molecular mechanism by which they affect the physiological health of oysters. The field experiment showed that more serious mortality of oysters was observed in the North Yellow Sea from July to September in 2018 (average survival rate of 75.11 %) than in 2019 (average survival rate of 85.78 %), with the proportion of Bacillariophyta (diatoms) in the phytoplankton community in 2018 lower than that in 2019. In comparison to 2019, reduced dry weight, lower glycogen and triglyceride contents in hepatopancreas, lower 17β-estradiol and testosterone concentrations in gonad, as well as a generally weaker immune response against Vibrio splendidus stimulation were detected in the oysters sampled in 2018. The treatment of oysters with either starvation (starvation group) or Nitzschia closterium f. minutissima feeding (N. closterium group) was conducted to verify the field findings, with individuals reared in natural seawater as control. After 40 days of N. closterium feeding, dry weight, glycogen and triglyceride contents in hepatopancreas significantly increased, as well as the biosynthesis of sex hormones and gonadal maturation were promoted compared to the control and starvation groups. Moreover, a much stronger immune response against V. splendidus stimulation was observed in the oysters of N. closterium group, with the fold-changes of norepinephrine content in serum, SOD activity in hepatopancreas, and the mRNA expression level of IL17-5 and HSP70 in haemocytes higher than those in the control and starvation groups. Collectively, these results suggested that lack of diatoms in the farming waters suppressed the energy storage and gonadal maturation of adult oysters, and also resulted in a compromised immune response against bacterial infection, which may be a leading cause of the mass mortality of oysters living in diatom-deficient waters during breeding seasons. • Mass mortality of oysters coincided with low diatom abundance in the seawater. • Lack of diatoms suppressed the energy storage and gonad maturation of oysters. • Lack of diatoms suppressed the immune response of oysters against bacterial infection. [ABSTRACT FROM AUTHOR]

Understanding the impact of environmental pollution on organismal energy budgets is crucial for predicting adaptive responses and potential maladaptation to stressors. However, the regulatory mechanism governing the trade-off between energy intake and consumption remains largely unknown, particularly considering the diverse adaptations influenced by exposure history in realistic field conditions. In the present study, we conducted a simulated field reciprocal transplant experiment to compare the energy budget strategies of Strauchbufo raddei tadpoles exposed to heavy metal. The simulated heavy metal concentrations (0.29 mg/L Cu, 1.17 mg/L Zn, 0.47 mg/L Pb, 0.16 mg/L Cd) mirrored the actual environmental exposure concentrations observed in the field habitat. This allowed for a comparison between tadpoles with parental chronic exposure to heavy metal pollutants in their habitat and those without such exposure. Results revealed that under heavy metal exposure, tadpoles originating from unpolluted areas exhibited heightened vulnerability, characterized by reduced food intake, diminished nutrient absorption, increased metabolism cost, reduced energy reserves, and increased mortality rates. In contrast, tadpoles originating from areas with long-term heavy metal pollution demonstrated adaptive strategies, manifested through adjustments in liver and small intestine phenotypes, optimizing energy allocation, and reducing energy consumption to preserve energy, thus sustaining survival. However, tadpoles from polluted areas exhibited certain maladaptive such as growth inhibition, metabolic suppression, and immune compromise due to heavy metal exposure. In conclusion, while conserving energy consumption has proven to be an effective way to deal with long-term heavy metal stress, it poses a threat to individual survival and population development in the long run. [Display omitted] • Tadpoles from polluted regions exhibit lower energy consumption. • Tadpoles from polluted regions display increased levels of fatty acids and amino acids. • Optimized energy allocation is more beneficial for tadpoles to adapt to heavy metal pollution. • The adaptability comes at the cost of compromised immunity and inhibited growth and development. [ABSTRACT FROM AUTHOR]

Smooth cordgrass (Spartina alterniflora) introduced to China in 1970 s for coastline stabilization threatening the habitat range of native Phragmites australis and even become more adaptive than P. australis. Thus, we used electronic universal testing machine and Van Soest method to compare the morphological and biomechanical responses of these two species to wave interference in the Yellow River Delta, east China. Our study showed that the morphological response of P. australis was more sensitive to waves with shorter individuals in wave zones but larger stem diameter and higher biomass than those in none-wave zones, while S. alterniflora did not exhibit such variations. In wave zones, S. alterniflora invaded P. australis’ habitat regardless higher stem-bending resistance of P. australis with excessive energy allocated in stem growth while decreasing reproduction and fitness. Compared with the none-wave zones, S. alterniflora allocated excessive energy in the stem to resist wind interference, and they are less fitted than P. australis. Thus, economic energy allocation to wave mechanical interference contributed to the successful invasion of S. alterniflora to landward in estuaries. S. alterniflora continued to expand landward in a semi-saline area but the community pattern may maintain the status quo for areas with low salinity and high wave interference.

The light-dependent zooxanthellate jellyfish Cassiopea sp. (the upside-down jellyfish) is invasive/exotic in many shallow and clear marine habitats, where the jellyfish might be exposed to high levels of ultraviolet radiation (UVR). Compared to other reef organisms, the sensitivity/resilience of the semi-transparent jellyfish to UVR exposure is overlooked. Therefore, we experimentally investigated the metabolic and physiological responses of Cassiopea sp. from the Red Sea to natural levels of underwater UVR following 16 days of exposure to three light treatments: 1) control group with only photosynthetically active radiation (PAR), 2) PAR+UV-B, and 3) PAR+UV-B+UV-A. While jellyfish body mass increased (by 40%) significantly in the control group, it did not increase in either of the UV treatments. However, both UV-exposed jellyfish had higher (98% to 120%) mitochondrial electron transport system (ETS) activity than the control group. Therefore, the results indicate elevated aerobic respiration rates in UV-exposed jellyfish (i.e., reflecting a higher energy cost of UVR exposure). Neither the lactate dehydrogenase (LDH) activity nor the available energy (Ea) exhibited different levels among UVR treatments compared to the control group. In contrast, pyruvate kinase activity was significantly lower (by 46%) in all UV-exposed jellyfish compared to the control group. Unchanged Ea and LDH activity combined with higher ETS activity indicates a high aerobic capacity of jellyfish, which might explain their ability to cope with UVR exposure-induced higher energy demands without inducing the onset of anaerobiosis. The results indicated that UV-A does not amplify or modulate jellyfish physiology and growth under UV-B exposure. In conclusion, the findings suggest that the jellyfish is more resilient (i.e., in terms of survival) to UVR than other cnidarians. This study on Cassiopea is the first to address its metabolic and physiological responses to UVR. Therefore, it could be used as a framework for further studies aiming to better understand jellyfish physiology.

Mozambique tilapia Oreochromis mossambicus (Peters) is an invasive fish and a continuous breeder in inland waters of India. Present investigation highlights the distinct developmental stages of developing ovary and associated changes in the energy content. This investigation helps to understand the allocation of energy for development of eggs, prespawn and also oral brooding by the female. Although it is a continuous breeder, based on size of the ovary, number of eggs, their size and energy content, immature, early maturing, developing, prespawning and spawning stages are clearly noticed. Egg diameter during development of ovary varied between 0.31 mm (immature) and 2.21 mm (spawning). Energy content of ovary from immature to spawning stage ranged from 20.7515 kJ g−1 dry ovary to 31.1560 kJ g−1 dry ovary. Nearly 28.73% of energy content of ovary is expended for spawning. Similarly, yolk‐sac fry utilized nearly 25.85% of energy of the fertilized egg for its development. Energy content of ovary of mouth‐brooding female averaged 22.9528 kJ g−1 dry ovary, which is comparable to energy content of early maturing stage of ovary (24.5558 kJ g−1 dry ovary). A strong correlation between body weight and energy content of the developing ovary (P < 0.01), and between ovary weight and energy content of ovary (P < 0.01), was evident. During mouth‐brooding, the fish continues to allocate energy to its developing ovary. Energy investment by the fish is the result of simultaneous processes associated with gonadal and somatic energy. As body size growth and gonadal development are interconnected, information on energy utilization by an iteroparous mouth‐brooding fish could provide the pattern of energy allocation during ovarian developmental phase. Further details of energy utilization, as explained in this paper, could be used as one of the factors to predict the efficiency of fish production. [ABSTRACT FROM AUTHOR]

The timetable of a metro system is essential for trains running safely and efficiently. For the design of a timetable, the potential power interruptions of energy supplies from the substations to the trains should be borne in mind. In case potential power interruptions occur, the backup running plan should be completed responsively to accommodate the passenger and energy demands In this study, we propose an energy supplementation strategy utilizing regenerative energy from decelerating trains in the event of power interruptions and develop a tri-objective optimization model incorporating passenger travel time, potential power interruption, and energy consumption. Particularly, for calculating regenerative energy utilization, we suggest a many-to-many energy allocation mechanism between decelerating and accelerating trains based on the real-time energy demands and supplies. A heuristic algorithm is developed to obtain a regular and cyclic timetable for minimizing passenger travel time, the potential power interruptions, and energy consumption. The suggested model and algorithm are tested based on the smart-card data collected from a bidirectional metro line in Beijing (China). The results show that the suggested approach significantly improves energy efficiency, reduces passenger waiting time, and decreases power interruption risks, compared with the currently used scheduling method. [ABSTRACT FROM AUTHOR]

Anthropogenically environmental acidification impacts aquatic organisms, including teleosts, the largest group of vertebrates. Despite its significance, how teleosts allocate nutrient and energy among their organs to cope with acidic stress remains unclear. Our integrated analysis of physiological, metabolic, and gene expression data reveals that Japanese medaka (Oryzias latipes) mobilize energy resources among organs in response to acidic conditions. We found that the muscles lost carbohydrates and proteins and the liver accumulates all macronutrients in both sexes. Notably, female-specific energy mobilization between the liver and ovary were triggered by estrogen signaling, resulting in improved oocyte maturation and ovulation. Female produced more offspring under acidic stress. Furthermore, the offspring embryos exhibited smaller diameters and earlier hatching but demonstrated growth rates and acid tolerance. These metabolic changes suggest a trade-off in energy allocation by suppressing basal maintenance (33 % decrease in oxygen consumption) and growth (25 % decrease in muscle mass) but enhancing energy storage (159 % increase in liver mass in males and 127 % in females) and reproduction (165 % increase in ovary mass). This reallocation may improve medaka fitness and population sustainability in acidic environments. Further investigation into more species is needed to project the survival of aquatic animals in an acidified future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Lactation is the most energetically demanding time in the life of female mammals. To maximize lifetime reproductive success, females of long-lived species, such as bats, face a trade-off between investing in current and future reproduction. However, it is unclear whether global warming could influence this trade-off through shifts in the energy budget: warmer temperatures may reduce thermoregulatory costs, leaving mothers with more energy available for maternal care or for improving their own body condition (BC), which may increase survival and ensure future reproduction. Here, we investigated whether lactating Bechstein's bats ( Myotis bechsteinii ) allocate the energy saved in optimally warm roosts into their own BC. We analysed a 14-year dataset on the individual BC of 237 females marked with radio-frequency identification tags from four wild maternity colonies. In two of the colonies, the temperature in the roosts, in which the females raised their offspring, was artificially kept in the bats' thermoneutral zone to reduce their thermoregulation costs. We found that BC shortly after the lactation period did not differ between mothers from heated and non-heated colonies. Our results suggest that mothers do not invest the energy saved in warmer roosts in their own BC, consistent with an increased investment in maternal care.

In this paper, we investigate the optimum energy allocation of dual-hop communication systems with AF protocol where we consider both coherent and differential transmission schemes. First, we demonstrate the performance of dual-hop communication systems in terms of symbol error rate (SER). Then, we carry out the optimum energy allocation which minimizes the error rate. Based on the optimized energy allocation, its effects on system performance are analyzed, and these results are compared with DF-based systems. We also compare the performance of AF-based systems depending on the transmission scheme.

Golden pompano (Trachinotus blochii) is becoming increasingly popular and produces high yields, but the growth differences between males and females are a concern. In this study, the differences between the growth of males and females were compared, and the transcriptome analysis of muscle tissues was performed. A significant difference between the growth of males and females was observed; females were found to be 17% larger than males after reaching 7 months of age. Gonadal histological analysis revealed that the ovaries were arrested in 7- to 9-month-old golden pompano, whereas the testes continued to develop. The AMPK and adipocytokine signaling pathways were also found to be involved in the regulation of muscle growth and metabolism. After reaching 7 months of age, the expression levels of glut1, glut4, ldh, gys, acsl and cpt2 in the muscle of females were lower than those in males, but the hk gene, which is involved in glycolysis, was found to remain highly expressed in females. Additionally, in females, the synthesis of arginine and ornithine and the production of carnosine were found to be inhibited, but the breakdown of glutamine was found to be enhanced and OXPHOS ability was found to be stronger in females after reaching 7 months of age. These results support a certain negative correlation between gonadal development and muscle metabolism depending on differences in energy distribution. Clearly, the faster growth in females after reaching 7 months of age was found to be associated with the more active metabolism of glucose, and amino acids, as well as stronger oxidative phosphorylation levels.

The phenomenon of food shortage is widespread in spider populations, which has a great impact on their growth, development, and survival. Pardosa pseudoannulata is a dominant spider species in rice fields and has an important controlling effect on rice pests. In this study, three feeding levels were tested at the juvenile stage (H, high feeding; M, medium dietary restriction; L, severe dietary restriction) and two at the adult stage (H and L). A total of six feeding levels were tested to explore the effects of dietary restriction on the development, longevity, nutrient content, and predation by P. pseudoannulata [HH (control group), HL, MH, ML, LH, LL]. The results showed that continuous dietary restriction (ML and LL groups) had negative impacts on the growth of P. pseudoannulata and positive impacts on longevity. Spiderlings suffered from dietary restrictions during the juvenile period, and when the restrictions were removed upon reaching adulthood (MH and LH groups), their lifespan started decreasing whilst their weight began returning to normal. This suggested that there might be a trade-off between the growth and longevity of the spider under dietary restrictions. The study also found that when food was severely restricted in the juvenile stage (LH and LL groups), the nutrient contents of the adult spider could return to the same level as the control group, but the predatory ability decreased. When food was moderately restricted in the juvenile stage (MH and ML groups), the predatory ability of the adult spiders improved, while nutrients of the adult spiders declined. Our results will provide an empirical basis for the protection and effective use of dominant spider species in agricultural fields.

A torrefied biomass polygeneration system (TBPGS) composed of a torrefied biomass gasification process, a combined cycle system, a water-gas-shift reactor (WGSR) process, and a CO methanation process, is developed to produce electricity, hydrogen, and synthetic natural gas (SNG) simultaneously. To cope with the daily energy patterns of power/SNG grid demands, three frameworks are addressed. The TBPGS is directly connected to power/SNG grids as the first framework (FW1). It is found that FW1 cannot cope with the SNG/power demand patterns due to SNG shortages appeared in some time intervals. To increase the operational flexibility of TBPGS, the TBPGS is connected to a combination of compressed hydrogen tank and PEM fuel cell stack as the second framework (FW2) and the TBPGS is connected to an SNG tank as the third framework (FW3). Based on the optimal allocation strategy for minimizing the daily net operating costs of FW2 and FW3, the comparative results show that (i) the total capital cost (TCI) of FW3 is lower than FW2 by 36.9%, (ii) the total operating cost (TOC) of FW3 is lower than FW2 by 5.4%, and (iii) the levelized cost of energy (LCOE) of FW3 is lower than FW2 by 31.7%. [Display omitted] • A torrefied biomass polygeneration system allocates power/gas ratios. • An optimal allocation approach dominates the system operation. • Two polygeneration allocation frameworks are presented. • The SNG tank as the allocation framework is superior to H2 tank. • The economic performance is evaluated by economic indicators of TCI, TOC, and LCOE. [ABSTRACT FROM AUTHOR]

The proliferation of renewable generation brings challenges to the power supply-demand balance. To relieve the power fluctuations caused by photovoltaic (PV) generation variability, a multi-timescale allocation algorithm that considers the allocation of available energy and power is proposed. Contracted demand response energy (CDRE) refers to the regulation energy, which is specified in contracts in advance, that can be used to relieve power fluctuations. First, the capacity of CDRE and available regulation power (RP) provided by load aggregators (LAs) that aggregate different demand response resources (DRRs) are estimated. In hour-timescale, CDRE is allocated to maximize the control economy of all participants, where a sample average approximation-based Stackelberg game is proposed to optimize the behavior of each participant based on considering PV generation uncertainty. In minute-timescale, RP is allocated to smooth the power fluctuations and minimize the power deviations based on the allocated CDRE results. Simulation on a modified IEEE-24 bus system verifies the effectiveness of the proposed algorithm in terms of reducing the power supply-demand imbalance with maximum revenue. [ABSTRACT FROM AUTHOR]

In order to maximize utilitarianism and fairness in allocating energy to electric vehicles (EVs) during outages, this study proposes an optimization method based on modified division rules. The idea of essential energy demand is introduced in this paper to maximize the number of EVs that are served during power contingencies. For EVs carrying out the time-critical task(s), the essential energy demand is defined as the amount of energy required by EVs to accomplish their upcoming task(s). For EVs carrying out delay-tolerant tasks, it is defined as the amount of energy required by EVs to travel to a nearby healthy charging station. To this end, an EV ranking mechanism is devised considering the full and essential energy demands along with the urgency of EVs. Subsequently, EVs with higher ranks are prioritized during energy allocation. The performance of the proposed method is compared with four existing division rules, i.e., proportional, constrained equal awards, constrained equal losses, and sequential priority rules. A utilitarianism index is proposed to analyze the performance of these methods and fairness is evaluated using existing indices, such as Jain's fairness index and cost of fairness index. The proposed method has outperformed existing division rules in both utilitarianism and fairness for the essential energy demand. Finally, a sensitivity analysis of uncertain parameters such as EV fleet size, available/required energy, and weight factors is carried out to analyze the performance of the proposed method under various conditions. [ABSTRACT FROM AUTHOR]