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The growth and associated traits of Aedes aegypti (L.) mosquitoes may adapt and evolve in response to the costs associated with body size in relation to latitudinal variation. We analyzed the life-history traits and energy reserves of field-collected mosquitoes from Taiwan, Thailand, and Indonesia along a latitudinal range spanning from 23°N to 6°S. A U-shaped relationship between body size and latitude was observed. Our study demonstrated the role of latitudinal temperature variations in determining the body size patterns of Ae. aegypti. Notably, the body size of the northern populations (from Taiwan) was significantly larger than those of the tropical populations from Thailand and Indonesia. Models have demonstrated that regional precipitation levels may contribute to body trait variations in certain high-latitude populations in Thailand. However, Indonesian populations have high development rates and large body sizes, indicating the involvement of other physiological traits in determining mosquito body size. The reproductive output of the adult females in this study was positively correlated with body size, but our measure of longevity did not covary significantly with the body size. By contrast, the reproductive output of mosquito-tested populations was in inverse proportion to longevity. Additionally, the mean teneral glycogen levels in the Indonesian and Thai populations were 2.5 times higher than those in theTaiwanese populations. The Indonesian and Thai populations had low mean generation and doubling times, resulting in a high intrinsic rate of increase compared with that of the Taiwanese populations, despite the Taiwanese populations having the highest net reproduction rate. Graphical Abstract

Background & objectives: Recently, the use of biodegradable and environment friendly plant-based bioinsecticides has received a great deal of attention from researchers to control insect disease vectors. The aim of this research is to determine the larvicidal efficacy of Ruta graveolens essential oil against third instar larvae of two species of mosquito (Culex pipiens and Culiseta longiareolata) and a biological model Drosophila melanogaster. Methods: Culiseta longiareolata and Culex pipiens larvae were collected from untreated areas located in Tebessa and Drosophila melanogaster, the wild strain collected from rotten apples in the Tebessa region. Ruta graveolens essential oil has been tested at different concentrations between 2.5μ/mL and 140μL/mL against third instar larvae of the three species under standard laboratory conditions according to the recommendations from the Word Health Organization. The effects were examined on mortality, growth and the main components (proteins, carbohydrates, lipids). Results: The essential oil showed larvicidal activity with LC50 and LC90 values (10.85μL/mL, 70.95μL/mL and 39.4μL/mL), (26μL/mL, 144.5μL/mL and 89.57μL/mL) against third instar larvae of Drosophila melanogaster, Culex pipiens and Culiseta longiareolata respectively. In addition, it disrupted the growth and several morphological malformations were observed. It also affected growth and the main components (proteins, carbohydrates, lipids). Interpretation & conclusion: The essential oil affected growth and energy reserves for all three species. The results indicated that the essential oil of Ruta graveolens has good potential as a source of natural larvicides.

Spiny lobsters have an extended pelagic larval development in oceanic waters, ending in a non-feeding post-larva that swims to coastal habitats to settle and molt to a benthic juvenile. The accumulation of energetic reserves by larvae is thought to be challenging, especially in tropical waters. We examined changes in fatty acid (FA) composition of the tropical Caribbean spiny lobster Panulirus argus for successive developmental stages sampled across the shelf and off the eastern Yucatan Peninsula, Mexico. Final-stage larvae accumulate considerable lipid reserves (26 ± 2.8% SD of dry weight), mostly saturated FAs (65.4 ± 2.1% of total FAs). Proportions of the FAs 14:0, 15:0, and 16:1n-7 tended to decrease from final larvae to settled juveniles, consistent with their use as a key energy source, although the dominant energy sources in all developmental stages were 16:0 and 18:0. In contrast, the percentages of 20:4n-6 (arachidonic acid) and 20:5n-3 (eicosapentaenoic acid) tended to increase with development, consistent with being conserved. Bacterial and flagellate FA markers dominated in final-stage larvae, indicating a microbial loop foodweb as the source of lipid reserves. Such foodwebs are characteristic of the oligotrophic waters in which the larvae of both sub-tropical and temperate spiny lobsters species are also found. Similarities in the accumulation and use of FAs between the tropical P. argus and spiny lobsters from cooler regions of the world suggest that their extended larval period is a means of acquiring sufficient energy reserves whilst feeding in oligotrophic oceanic waters.

Low winter temperatures severely stress newly arriving insect species. Adaptive evolutionary changes in cold tolerance can facilitate their establishment in new environments. Ambrosia artemisiifolia , a noxious invasive plant, occurs throughout China. Ophraella communa , a biological control agent of A. artemisiifolia , mainly occurs in southern China. However, in 2012, it established populations in Beijing (39.98°N, 115.97°E) following introduction from Laibin (23.62°N, 109.37°E), implying cold adaptation. The mechanisms underlying its rapid evolution of cold tolerance remain unknown. We investigated the levels of cryoprotectants and energy reserves in adult O. communa from two latitudes. In high-latitude insects, we found high trehalose, proline, glycerol, total sugar, and lipid levels; five potential genes ( Tret1a , Tret1b , Tret1-2 , P5CS , and GST ), responsible for regulating cold tolerance and involved in trehalose transport, proline biosynthesis, and glutathione S-transferase activation, were highly expressed. These hybridisation changes could facilitate cold temperature adaptation. We demonstrate the genetic basis underlying rapid adaptation of cold tolerance in O. communa , explaining its extension to higher latitudes. Thus, specialist herbivores can follow host plants by adapting to new temperature environments via rapid genetic evolution.

Backfat thickness could reflect the energy reserve of female pigs that is required for their reproductivity, especially gilts that might be selected as replacements. In this study, genetic and phenotypic correlations between backfat thickness (BF) and body weight (BW) at 28 weeks of age, and reproduction traits were estimated. They were considered for the possibility of using BF at the pre-selective stage as an early indicator of sow’s reproduction potential. Pedigree information, BF and BW at 28 weeks of age, age at first farrowing (AFF), transformed proportion of piglet loss at birth (tPL), and transformed weaning to first service interval (tWSI) of 806 primiparous Landrace sows were used to estimate the variance components by a restricted maximum likelihood procedure with an average information algorithm for multivariate analysis. The genetic correlation between BF and BW was 0.70 ± 0.13. Both BF and BW had a negative genetic correlation with AFF but not with tWSI. Genetic correlation estimates between tPL and other traits were unclear due to high standard error. The genetic correlation between AFF and tWSI was 0.78 ± 0.36. There were 19.35% of sires, 26.34% of dams, and 25.81% of sows that had preferable estimated breeding values for BF, BW, AFF, and WSI. These values indicated the feasibility of using selection index to improve BF and BW at the pre-selective stage and reduce AFF and tWSI of replacement gilt simultaneously. The estimation of genetic correlation between PL and other traits warrants further study in larger populations.

To cope with wind power uncertainty, balancing authorities are required to procure adequate ancillary services (ASs) with the aim of maintaining the security of the power system operation. The transmission system operator (TSO) is responsible for maintaining the balance between supply and demand in delivery hours. Besides the generating units, demand response (DR) has the potential capabilities to be considered as a source of AS. The demand‐side AS can be used both locally (by the local entities in distribution networks) and system‐wide (by the TSO). However, the optimal coordination between the local and global beneficiaries is a challenging task. This study proposes a distributed DR market model, in which the DR is traded as a public good among the providers and beneficiaries through the local DR markets. The local DR markets can be run in each load bus to trade the DR provided by retail customers connected to that bus with the buyers. To include the interactions between the energy/reserve market and the local DR markets, a bi‐level programming model is proposed. The bi‐level problem is translated into a single‐level mixed‐integer linear programming problem using the duality theorem. The proposed model is verified by simple and realistic case studies.

The occurrence of sub-optimal temperatures during development of immature parasitoids can have important consequences on adult fitness. We investigated the impact of different regimes of low temperature on emergence, differential mortality, longevity and fecundity in Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae). The host-feeding behaviour of adult females was also measured as an indicator of energy reserve at emergence. Acclimation of 30 days at 10 °C or 24 days at 13 °C allowed T. brassicae immatures to develop with a lower mortality than those exposed directly at 5 °C. Longevity and fecundity of females decreased at a lower rate with acclimation at 10 °C suggesting that acclimation at 13 °C may have depleted the energy reserves of individuals more than acclimation at 10 °C. Short photoperiod exposure during the maternal generation had no effect on progeny’s fitness. We found no difference among the treatments in females’ host-feeding behaviours, in differential mortality at emergence, in female’s mobility and in F1 sex ratio.

The aim of this study was to evaluate the coupled impact of an herbicide, ethofumesate, and temperature on the cellular energy metabolism of juvenile roach, especially on the glycolysis pathway. Juvenile roach were exposed to 0, 0.5, 5, and 50 μg/L of ethofumesate for 7 days in laboratory conditions at two temperatures (10 and 17 °C). The energy reserves (carbohydrate, lipid, and protein) were quantified, since the availability of substrates regulates the glycolysis. Then, the glycolysis was studied at the biochemical level by the measurement of the glycolytic flux and at the molecular level with the measurement of the relative expression of four genes encoding for glycolysis enzymes. This study revealed different effect of ethofumesate on the glycolysis pathway according to the temperature of exposure. Indeed, at 10 °C, it appeared that only the molecular regulation level was affected, whereas, at 17 °C, ethofumesate acted on the biochemical level. The differences observed between the two exposures imply the establishment of different strategies in order to maintain to cope with stress according to the temperature of exposure.

Energy investment in reproduction and somatic growth was investigated for summer spawners of the Argentinean shortfin squid Illex argentinus in the southwest Atlantic Ocean. Sampled squids were examined for morphometry and intensity of feeding behavior associated with reproductive maturation. Residuals generated from length‐weight relationships were analyzed to determine patterns of energy allocation between somatic and reproductive growth. Both females and males showed similar rates of increase for eviscerated body mass and digestive gland mass relative to mantle length, but the rate of increase for total reproductive organ weight relative to mantle length in females was three times that of males. For females, condition of somatic tissues deteriorated until the mature stage, but somatic condition improved after the onset of maturity. In males, there was no correlation between somatic condition and phases of reproductive maturity. Reproductive investment decreased as sexual maturation progressed for both females and males, with the lowest investment occurring at the functionally mature stage. Residual analysis indicated that female reproductive development was at the expense of body muscle growth during the immature and maturing stages, but energy invested in reproduction after onset of maturity was probably met by food intake. However, in males both reproductive maturation and somatic growth proceeded concurrently so that energy allocated to reproduction was related to food intake throughout the process of maturation. For both males and females, there was little evidence of trade‐offs between the digestive gland and reproductive growth, as no significant correlation was found between dorsal mantle length‐digestive gland weight residuals. The role of the digestive gland as an energy reserve for gonadal growth should be reconsidered. Additionally, feeding intensity by both males and females decreased after the onset of sexual maturity, but feeding never stopped completely, even during spawning.

To maintain optimal fitness, a cell must balance the risk of inadequate energy reserve for response to a potentially fatal perturbation against the long-term cost of maintaining high concentrations of ATP to meet occasional spikes in demand. Here we apply a game theoretic approach to address the dynamics of energy production and expenditure in eukaryotic cells. Conventionally, glucose metabolism is viewed as a function of oxygen concentrations in which the more efficient oxidation of glucose to CO2 and H2O produces all or nearly all ATP except under hypoxic conditions when less efficient (2 ATP/ glucose vs. about 36ATP/glucose) anaerobic metabolism of glucose to lactic acid provides an emergency backup. We propose an alternative in which energy production is governed by the complex temporal and spatial dynamics of intracellular ATP demand. In the short term, a cell must provide energy for constant baseline needs but also maintain capacity to rapidly respond to fluxes in demand particularly due to external perturbations on the cell membrane. Similarly, longer-term dynamics require a trade-off between the cost of maintaining high metabolic capacity to meet uncommon spikes in demand versus the risk of unsuccessfully responding to threats or opportunities. Here we develop a model and computationally explore the cell's optimal mix of glycolytic and oxidative capacity. We find the Warburg effect, high glycolytic metabolism even under normoxic conditions, is represents a metabolic strategy that allow cancer cells to optimally meet energy demands posed by stochastic or fluctuating tumor environments.