Immature Survival Research Articles

Spatial heterogeneity in the abundance and fecundity of Arctic mosquitoes

AbstractThe abundance of mosquitoes is strongly influenced by biotic and abiotic factors that act on the immature (aquatic) and adult (terrestrial) life stages. Rapid changes in land use and climate, which impact aquatic and terrestrial mosquito habitat, necessitate studying the ecological mechanisms, and their interplay with the changing environment, that affect mosquito abundance. These data are crucial for anticipating how environmental change will impact their roles as pests, disease vectors, and in food webs. We studied a population of Arctic mosquitoes (Aedes nigripes, Diptera: Culicidae) in western Greenland, a region experiencing rapid environmental change, to quantify spatial variation in adult abundance and reproduction. Using sweep nets, we collected about sevenfold more mosquitoes within the town of Kangerlussuaq and within a low‐elevation tundra valley compared to three other tundra locations. Dissections of adult female mosquitoes revealed that only 17% were gravid overall, with a range of 7–43% among sites. If gravid, mosquitoes matured an average of 60 eggs per individual—more in larger females. We found no indication of autogenous egg development. Analyses using our field data indicated that spatial variation in adult fecundity and survival of immatures could each account for a 10‐fold range in the per capita growth of mosquito populations. The availability of vertebrate hosts and aquatic habitat is changing in many parts of the Arctic and can be expected to influence Arctic mosquito abundance. In the Arctic, and elsewhere, life‐history data from natural populations of mosquitoes will significantly aid in understanding controls on the abundance of these globally ubiquitous insects.

Covariates streamline age‐specific early life survival estimates of two chelonian species

AbstractDelayed maturity and high survival rates of immatures and adults characterize long‐lived species’ life histories. Understanding how these traits interact in stochastic environments is essential to understand early life in long‐lived species and to assist conservation planning. Unfortunately, available information of demographic traits in immatures are often fragmentary and the logistical difficulties of capturing and recapturing this cohort leave little room for improvement. Published immature chelonian survival estimates vary broadly, are often not age‐specific, and lack precision. In an attempt to overcome this issue, we developed a novel modelling approach based on Capture‐Recapture data to obtain robust age‐specific survival probabilities in two chelonian species (the freshwater European pond turtle, Emys orbicularis, and the terrestrial Hermann's tortoise, Testudo hermanni). More specifically, we show that implementing a linear relationship between survival probabilities and age does not distort survival estimates and improves precision. Both species display a progressive increase in survival with age, reaching a plateau at the ages of four to five. As maturity occurs later in both species (8–12 years‐old), the survival plateau might be governed by the final hardening of the carapace, which brings obvious survival benefits. Taking advantage of the flexibility of multievent models we encourage a systematic field approach even when very large samples from immatures cannot be amassed. Only so can demographic traits in chelonians, and more generally in long‐lived species, be properly explored.

Multiple stressors: modeling the effect of pollution, climate, and predation on viability of a sub‐arctic marine bird

AbstractNegative effects of long‐transported pollutants, such as many persistent organic pollutants (POPs), on seabirds and other top predators have been documented for decades. Yet, the concentrations, and hence, the negative impacts of many POPs have recently declined in the Northern Hemisphere. However, organisms are exposed to multiple stressors and the impacts of pollution act in concert with both natural and other anthropogenic stressors. In theory, this means that even sub‐lethal POP concentrations may cause adverse effects if they co‐occur with increased levels of other stressors. We tested the multiple stress hypothesis on common eiders, a marine duck with a northern geographical distribution, by assessing the relative importance of pollution, climate (winter sea surface temperature; SSTw), and egg predation on population dynamics and viability (i.e., extinction risk) using Leslie‐matrix population models. The model was parametrized by estimating reproduction and apparent adult survival using long‐term data from a common eider population in sub‐arctic Europe. Average annual adult survival was 0.80 (coefficient of variation [CV] = 22.00%) and showed a negative, both direct and delayed, relationship with SSTw. Average clutch size was 4.41 eggs (CV = 5.12%) and varied in time showing periods of both positive and negative trends, but showed no relationship with SSTw. We based immature survival on estimates from literature: 0.52 and 0.68 for juveniles and yearlings, respectively. Our model supported the multiple stress hypothesis as changes in a single stressor did not induce extinctions, unless the magnitude of our manipulations was extreme except for egg predation. The effect of pollution was, however, increasingly negative when it co‐occurred with a warming climate and egg predation—and population viability was lowest when all the stressors occurred simultaneously.

Cost-effectiveness of niraparib versus routine surveillance, olaparib, and rucaparib for the maintenance treatment of adult patients with ovarian cancer in the United States.

5559 Background: To estimate the cost-effectiveness of niraparib, a poly (ADP-ribose) polymerase (PARP) inhibitor, compared with routine surveillance (RS), olaparib and rucaparib for the maintenance treatment of patients with recurrent ovarian cancer. Methods: A decision-analytic model estimated the cost per quality-adjusted life-year gained for niraparib versus RS, olaparib and rucaparib from a US payer perspective. Recurrent ovarian cancer patients with or without germline BRCA mutation, who were responsive to their last platinum-based chemotherapy regimen, entered the model (non-gBRCAmut, gBRCAmut). The model had three health states; progression-free disease, progressed disease and dead. For non-gBRCAmut and gBRCAmut, mean progression-free survival (PFS) was estimated for niraparib and RS, and rucaparib using parametric survival distributions based on ENGOT-OV16/NOVA (Niraparib Phase III trial) and ARIEL3 (Rucaparib Phase III trial), respectively. For non-gBRCAmut, olaparib PFS was estimated from Study 19 (Olaparib Phase II trial). For gBRCAmut, a cost-minimisation analysis was conducted versus olaparib. Due to immature overall survival (OS) data in ENGOT-OV16/NOVA and ARIEL3, mean OS benefit was estimated as double the mean PFS benefit for niraparib, olaparib and rucaparib versus RS. Costs included; drug, chemotherapy, monitoring, adverse events, and terminal care. EQ-5D captured quality-of-life. A 3% annual discount rate was used. Results: Treatment with niraparib increased costs and QALYs versus RS, with an incremental cost-effectiveness ratio of $94,186 and $58,804, for non-gBRCAmut and gBRCAmut. Niraparib had lower costs and higher QALYs compared to olaparib and rucaparib in both populations, with a cost difference of -$57,575 and -$60,400 versus olaparib, and a cost difference of -$117,916 and -$261,950 versus rucaparib for non-gBRCAmut and gBRCAmut. Conclusions: These estimates indicate that niraparib was cost-effective compared to olaparib and rucaparib. Additionally, the cost-effectiveness ratio falls within an acceptable range versus RS. Mature OS data is required to validate these results.

Effects of scarcity and excess of larval food on life history traits of Aedes aegypti (Diptera: Culicidae).

Few studies have assessed the effects of food scarcity or excess on the life history traits of Aedes aegypti (L.) (Diptera: Culicidae) independently from larval density. We assessed immature survival, development time, and adult size in relation to food availability. We reared cohorts of 30 Ae. aegypti larvae from newly hatched to adult emergence with different food availability. Food conditions were kept constant by transferring larvae each day to a new food solution. Immature development was completed by some individuals in all treatments. The shortest development time, the largest adults, and the highest survival were observed at intermediate food levels. The most important effects of food scarcity were an extension in development time, a decrease in the size of adults, and a slight decrease in survival, while the most important effects of food excess were an important decrease in survival and a slight decrease in the size of adults. The variability in development time and adult size within sex and treatment increased at decreasing food availability. The results suggest that although the studied population has adapted to a wide range of food availabilities, both scarcity and excess of food have important negative impacts on fitness.

PRM58 - The use of Historical Trial Data to Inform Extrapolations of Immature Survival Data within a Bayesian Framework in Comparison to Standard Approaches

PRM58 - The use of Historical Trial Data to Inform Extrapolations of Immature Survival Data within a Bayesian Framework in Comparison to Standard Approaches

Chronic toxicity of amitraz, coumaphos and fluvalinate to Apis mellifera L. larvae reared in vitro

The effects of chronic exposure to common acaricides on Apis mellifera survival, developmental rate and larval weight were tested in the laboratory. Larvae were reared in vitro and fed a diet containing amitraz: 1.5, 11, 25 and 46 mg/L; coumaphos: 1.8, 6, 8 and 25 mg/L; or fluvalinate: 0.1, 1, 2.4 and 6 mg/L. The dependent variables were compared for groups feeding on treated diets and control diets: positive control, 45 mg/L dimethoate; solvent control; and negative control. Bee survival decreased in the 46 mg/L amitraz and 25 mg/L coumaphos treatments but not in any fluvalinate treatment. Furthermore, the developmental rate decreased in individuals treated with 46 mg/L amitraz. In our study, larvae exposed to acaricides at concentrations similar to maximum residue in pollen and honey/nectar had no detectable change in survival or developmental rate. Given that pollen and honey/nectar represent only a small part of larval diet, we suggest that residues of amitraz, coumaphos and fluvalinate at the levels we tested are unlikely to impact immature worker bee survival in the field, though our data do not preclude any sublethal effects that may result from bee exposure to these compounds or possible synergisms when they co-occur in bee colonies.

Intraspecific variations on thermal susceptibility in the predatory mite Neoseiulus barkeri Hughes (Acari: Phytoseiidae): Responding to long-term heat acclimations and frequent heat hardenings

Biological control of spider mites using phytoseiid mites is frequently being disrupted by high temperatures, which results in an important and urgent research topic. We hypothesized that this scenario could be ameliorated if the thermal tolerance of a certain phytoseiid mite is enhanced. In this study, a high temperature adapted strain (HTAS) of the predatory mite Neoseiulus barkeri Hughes was selected from its conventional strain (CS) via a long-term heat acclimation (maintained at 35 °C) and frequent heat hardenings (exposed at 45 °C for 2 h every 15–25 days) over multiple generations. As expected, heat acclimation greatly improved the survival probabilities of N. barkeri when a single heat stress event occurred, with a median lethal time (e.g., at 45 °C) calculated as 15.2 h for HTAS females and 1.9 h for CS ones, respectively. After the heat acclimatory, HTAS showed a faster growth and developmental rate, and a higher immature survival rate than CS did; a significant reduced total fecundity rather than longevity was observed at 35 °C; a shifting from larger females to smaller males was observed (about 21% reduced in female ratio). Meanwhile, single heat stress event (e.g., exposed at 42 °C for 4 h) had a detrimental effect on the reproductive traits of the newly-emerged females, particularly obvious for mites from CS colony, by delaying the onset of oviposition and reducing reproductive output. This is the first experimental demonstration that the artificially heat acclimatory can shape the intraspecific variations on thermal susceptibility in a phytoseiid mite. It is suggested that HTAS N. barkeri might be a promising strain for the biological control of the high temperature favored spider mites, and more field and greenhouse trials should be evaluated in the future.

Life histories of an invasive and native ladybird under field experimental conditions in a temperate climate

AbstractAmong characteristics that are thought to determine the success of invasive species, life‐history traits feature prominently. However, in most cases, these have been determined under laboratory conditions. Here, we use a field set‐up to determine immature development time and survival of invasive Harmonia axyridis (Pallas) and native Adalia bipunctata L. (both Coleoptera: Coccinellidae). On caged Tilia × europaea L. cv. Pallida trees (Malvaceae) with ample amounts of aphid food, we introduced freshly hatched larvae of a single or of both ladybird species and followed their development until emergence of adults. Under the condition of ample prey availability, both ladybird species apparently hardly interacted and intraguild predation did not cause significant mortality. Development time of both species is in line with data from laboratory tests under controlled conditions. Immature survival can reach high levels, but is considerably higher for H. axyridis (44–100%) than for A. bipunctata (11–77%), resulting in faster increase of H. axyridis populations, which is one of the factors that may explain its invasion success.

Effects of Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae) growing conditions and nutrient content on the performance of a leaf-mining fly, Hydrellia purcelli Deeming (Diptera: Ephydridae)

ABSTRACTHost plant quality for insects used in weed biological control influences their performance and hence their ability to suppress target host populations. Determining the specific response of these insects to the quality of their host is important because phytophagous insects have variable tolerances of the different constituents of host plant quality, most notably dietary nitrogen (N), but also other physical and chemical components. The invasive aquatic weed Hydrilla verticillata (L.f.) Royle (Hydrocharitaceae) was cultivated under varying nutrient conditions to determine the influence of plant quality on immature survival, development, larval mining, reproductive output and adult longevity of a leaf-mining fly Hydrellia purcelli Deeming (Diptera: Ephydridae). Additionally, field-collected H. verticillata was included in the investigations to assess the potential performance of H. purcelli in the field. Variation in plant tissue N and phosphorus (P) concentrations had no effects on larval survival, female fecundity, or adult longevity, but high levels of N and P were associated with reduced immature development times and higher body mass of females. Overall, plant quality factors not measured in this study appeared to have a greater impact on the performance of the fly, rather than dietary N and P. The results provided insights into optimal mass-rearing conditions for H. purcelli and the potential performance of the fly in the field in South Africa. Furthermore, the results demonstrate the importance of considering other aspects of plant quality for insect agents, in addition to dietary N and P, when developing mass-rearing protocols or predicting their potential impact in the field.

Do characteristics of pollinator‐friendly gardens predict the diversity, abundance, and reproduction of butterflies?

AbstractPollinator declines have motivated efforts to plant nectar and host plants for butterflies and other pollinators, but whether gardens promote pollinator conservation requires further investigation.We established garden plots to determine whether plant type (native vs. exotic) and weed maintenance (low or high) influence adult butterfly abundance and species richness, and the abundance and survival of immature stages of four species (monarch, queen, black swallowtail, and gulf fritillary). To assess how predator activity and mortality of immature stages might differ inside gardens compared to other suitable habitat patches, we compared caterpillar survival on sentinel host plants placed within and outside of plots.The abundance and species richness of adult butterflies (all taxa) increased with the number of flowering plants per plot, but did not depend on plant type or weeding treatment. Exotic plots had greater adult monarch and gulf fritillary abundances, greater monarch and queen egg counts, and lower black swallowtail caterpillar counts relative to native plots.The survival of immature stages (egg to instar 5) ranged from 2 to 13% and was similar across plots, except for gulf fritillary larvae, which had higher survival in exotic plots. Monarch caterpillar mortality risk was higher on sentinel plants placed inside plots, relative to those outside of plots.This study suggests that garden plots attracted a diversity of adult butterflies and supported the reproduction of focal species. Given lower immature monarch survival within versus outside of plots, further work is needed to examine natural enemy pressure within pollinator gardens.

Suitability of Bemisia tabaci (Hemiptera: Aleyrodidae) biotype-B and Myzus persicae (Hemiptera: Aphididae) as prey for the ladybird beetle, Serangium japonicum (Coleoptera: Coccinellidae)

The ladybird, Serangium japonicum (Coleoptera: Coccinellidae), is one of the most important predators of whiteflies in China, however, the suitability of different kinds of prey and nutritional requirements of this predator are poorly studied. The objectives of the present study were to investigate the pre-imaginal development, percentage survival of immatures, adult longevity and fecundity of S. japonicum when reared on two different species of prey, mixed ages of the cotton whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) biotype-B (i.e., eggs and nymphs) and green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) in order to quantify their relative suitability as prey under laboratory conditions of 25 ± 1°C, 50 ± 10% RH and a photoperiod of 16L : 8D. The results of this study indicate that the total developmental period (from egg to adult) was shorter when they were fed on B. tabaci (18.29 ± 0.13 days) than on M. persicae (19.85 ± 0.22 days). The percentage survival of the immatures, growth index, development rate, adult fresh weight, fecundity and percentage of eggs hatching were higher and the pre-oviposition period was significantly shorter when S. japonicum were fed on B. tabaci than on M. persicae. In contrast, there was no significant difference in their longevity and oviposition period when fed on B. tabaci and M. persicae. The results indicate that as a diet for S. japonicum M. persicae is inferior to B. tabaci. This is the first record of S. japonicum being able to complete its development feeding exclusively on M. persicae. Since B. tabaci and M. persicae often simultaneously occur in vegetable fields, these results indicate that it is likely that S. japonicum could be utilized to control mixed populations of aphids and whiteflies, and furthers our understanding of ladybird population dynamics in the field in relation to the availability of different species of prey.

Anthelmintic therapy of equine cyathostomin nematodes – larvicidal efficacy, egg reappearance period, and drug resistance

Cyathostomins are ubiquitous in grazing horses across the world, and anthelmintic resistance has been reported with increasing levels over past decades. The aims of the present study were (i) to investigate the efficacy against encysted larval stages of moxidectin (0.4 mg/kg) and fenbendazole (10 mg/kg daily for five consecutive days) and compare these regimens at 2 and 5 weeks post-treatment, (ii) to investigate individual cyathostomin species associated with shortened egg reappearance periods, and (iii) to document species exhibiting decreased susceptibility to the evaluated compounds. Thirty-six ponies were allocated to treatment groups with half euthanatized 2 weeks post-treatment, and the remainder necropsied after 5 weeks. Luminal and mucosal worm counts were conducted and strongyle egg counts were determined at weekly intervals. At 2 weeks, mean reductions of early L3s were 50.4% and 73.8% for fenbendazole and moxidectin, respectively. At 5 weeks, the respective efficacies were 51.3% and 71.8%. Two week efficacies against late L3s and L4s (LL3s/L4s) were 70.8% and 74.6% for fenbendazole and moxidectin, respectively, whereas very low numbers were found in all three groups at 5 weeks. None of the mucosal counts were significantly different between treatment groups. Fenbendazole and moxidectin reduced luminal worm counts by 93.2% and 98.3% at 2 weeks following administration, with moxidectin group adult counts being significantly lower than the other two groups (P < 0.0001). Both treatment groups had increased counts 3 weeks later (P = 0.0415). A moxidectin ERP of 4 weeks was associated with surviving luminal L4s, and adult species contributing to this were Cyathostomum catinatum, Cylicostephanus longibursatus, Cylicocyclus ashworthi and Cylicocyclus nassatus. This study documented (i) larvicidal efficacy of fenbendazole much lower than historical standards, (ii) survival of luminal immatures (L4) following moxidectin administration, and (iii) new information about cyathostomin species associated with these phenomena.

Influence of low static magnetic field (SMF) on immature development and survival of the mosquito, Culex pipiens (Diptera: Culicidae)

In this study, experiments were performed to investigate the effect of the low static magnetic field (SMF) on hatchability, development, and survival of Culex pipiens mosquito immature under laboratory conditions. Egg-rafts of Cx. pipiens were exposed to SMF at different intensities of 5 mT, 25 mT, and 50 mT for 20 minutes at a temperature of 28±1 oC. Hatching rate, hatching delay time, and larval development significantly affected by SMF. The numbers of hatched larvae decreased with increasing SMF at 50 mT (133.33 ± 6.0) as compared to the control (302.23 ± 10.9). Also, the hatching rate significantly lengthened (P < 0.05) with high intensity of SMF. A total of 88.3% and 44.33% eggs hatched at 5 mT and 50 mT, respectively. For Cx. pipiens immatures, the duration time shortened and survival (%) reduced after exposure to high dose (50 mT) than to low dose (5 mT). We concluded that SMF affects egg hatchability and immature development which could be applied as a strategy in mosquito control.

NMNAT3 is protective against the effects of neonatal cerebral hypoxia-ischemia.

ObjectiveTo determine whether the NAD+ biosynthetic protein, nicotinamide mononucleotide adenylyltransferase‐3 (NMNAT3), is a neuroprotective inducible enzyme capable of decreasing cerebral injury after neonatal hypoxia‐ischemia (H‐I) and reducing glutamate receptor‐mediated excitotoxic neurodegeneration of immature neurons.MethodsUsing NMNAT3‐overexpressing mice we investigated whether increases in brain NMNAT3 reduced cerebral tissue loss following H‐I. We then employed biochemical methods from injured neonatal brains to examine the inducibility of NMNAT3 and the mechanism of NMNAT3‐dependent neuroprotection. Using AAV8‐mediated vectors for in vitro neuronal NMNAT3 knockdown, we then examine the endogenous role of this protein on immature neuronal survival prior and following NMDA receptor‐mediated excitotoxicity.ResultsNMNAT3 mRNA and protein levels increased after neonatal H‐I. In addition, NMNAT3 overexpression decreased cortical and hippocampal tissue loss 7 days following injury. We further show that the NMNAT3 neuroprotective mechanism involves a decrease in calpastatin degradation, and a decrease in caspase‐3 activity and calpain‐mediated cleavage. Conversely, NMNAT3 knockdown of cortical and hippocampal neurons in vitro caused neuronal degeneration and increased excitotoxic cell death. The neurodegenerative effects of NMNAT3 knockdown were counteracted by exogenous upregulation of NMNAT3.ConclusionsOur observations provide new insights into the neuroprotective mechanisms of NMNATs in the injured developing brain, adding NMNAT3 as an important neuroprotective enzyme in neonatal H‐I via inhibition of apoptotic and necrotic neurodegeneration. Interestingly, we find that endogenous NMNAT3 is an inducible protein important for maintaining the survival of immature neurons. Future studies aimed at uncovering the mechanisms of NMNAT3 upregulation and neuroprotection may offer new therapies against the effects of hypoxic‐ischemic encephalopathy.

Selection and inheritance of developmental variants of Propylea dissecta under thermal stress conditions

The present study aims to understand the influence of two thermal extremes (15°C and 35°C) as thermal stressors on the selected line of developmental variants (slow and fast developers) in Propylea dissecta and to compare it with the response at the optimal temperature (27°C). The ratio of slow and fast developers within an egg batch differed with thermal extremes irrespective of F1 and F15 generations. Adult body mass got depressed after selection for control slow developers at 15°C while it got enhanced for selected fast developers at 35°C. More selected slow developers were found at low temperature and more selected fast developers at high temperature. Selection probably favours the enhancement of immature survival and emergence ratio which was found to be highest for selected fast developers at 35°C and selected slow developers at 15°C. Population level disparity on thermal confliction was observed in ladybird post selection over several generations. Therefore, we put forward that exposure thermal extremes over a long duration, causes an adaptive differentiation in thermal responses of slow and fast developers.

The influence of temperature on life history traits of Diadegma mollipla (Hymenoptera: Ichneumonidae), an African parasitoid of the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)

The use of Diadegma mollipla (Holmgren) as a biocontrol agent for diamondback moth (DBM)—a notorious pest of crucifers—can potentially be improved with increased scientific knowledge of the D. mollipla’s life history. This study investigated the influence of temperature on the life history traits of D. mollipla parasitizing DBM under laboratory conditions with 20 female D. mollipla for each of five constant temperatures i.e., 15, 20, 25, 30 and 35 °C. Data analysis using curvilinear regression models showed that D. mollipla’s highest intrinsic and finite rates of population increase, net reproductive rate, survival of immatures, daily fertility, shortest immature development and doubling times were achieved between 26 and 30 °C. Thus the results of this study provide evidence to that D. mollipla does not thrive well outside the 26–30 °C temperature range. These results provide baseline information for guiding the use of D. mollipla in the biological control of the destructive DBM pest.

Influence of Host Quality and Temperature on the Biology of Diaeretiella rapae (Hymenoptera: Braconidae, Aphidiinae).

Biological features of Diaeretiella rapae (McIntosh), an aphid parasitoid, are conditioned by temperature and host. However, studies of host quality changes due to temperature adaptability have not been performed previously. Therefore, this study evaluated the adaptability of Lipaphis pseudobrassicae (Davis) and Myzus persicae (Sulzer) to high temperature, high temperature effect on their quality as hosts for D. rapae, and on parasitoid's thermal threshold. Aphid development, survivorship, fecundity, and longevity were compared at 19 °C and 28 °C. Host quality in different temperatures was determined through evaluation of parasitoid biology. Thermal threshold of D. rapae was determined using development time data. At 28 °C, development time, rate of immature survival, and total fecundity rates were greater in L. pseudobrassicae than in M. persicae. Development time of D. rapae in L. pseudobrassicae was shorter than that in M. persicae at 28 °C and 31 °C for females and at 31 °C for males. The thermal threshold of D. rapae was 6.38 °C and 3.33 °C for females and 4.45 °C and 3.63 °C for males developed on L. pseudobrassicae and M. persicae, respectively. Diaeretiella rapae size gain was greater in L. pseudobrassicae than that in M. persicae at 25 °C and 28 °C. Lipaphis pseudobrassicae showed better adaptation than M. persicae to elevated temperatures, which resulted in a better quality host for D. rapae at temperatures of 28 °C and 31 °C and a higher lower thermal threshold when the parasitoid developed within L. pseudobrassicae. The host's adaptation to high temperatures is a determinant of host quality for the parasitoid at that same climatic condition.

Sunitinib in the treatment of renal cell carcinoma: an update on recent evidence.

Sunitinib is a multitarget tyrosine kinase inhibitor endowed mainly by antiangiogenic effects, although an indirect inhibitory effect on tumor growth and, more recently, a complex activity on antitumor immune response has been described. From approval by the US Food and Drug Administration (FDA) in January 2006, sunitinib represents a key molecule in the treatment of metastatic renal cell carcinoma (mRCC) due to the peculiar molecular pathogenesis of this neoplasm. Over the past 10 years, clinical trials and real-world experiences helped clinicians to understand how, when and for how long to use sunitinib. Although a huge amount of data evidenced the relationship existing between sunitinib dose intensity and improved clinical outcome, the management of sunitinib-induced adverse events is often complex; thus, alternative schedules have been proposed over time which allow increased tolerability, without decreased daily sunitinib exposure, leading to improved clinical outcomes. To date, combinations of sunitinib with other approved targeted agents did not demonstrate any significant benefit over its single-agent use, mainly due to tolerability issues. Sunitinib has also been tested in the adjuvant setting, within the ASSURE and S-TRAC trials, with opposite results; indeed, equivocal risk-stratification criteria, as well as immature overall survival (OS) data prevent any definitive conclusion on this important issue. Despite being on the market for a long time, sunitinib still plays a role as the 'comparator arm' of a number of trials in the field of mRCC. Combinations with immune checkpoint inhibitors and vaccines look promising; once again, sunitinib can help us to optimize mRCC management.

Effect of temperature on the demographic parameters of Asiatic apple leafminer, Phyllonorycter ringoniella Matsumura (Lepidoptera: Gracillariidae)

Asiatic apple leafminer, Phyllonorycter ringoniella Matsumura (Lepidoptera: Gracillariidae) is an important insect pest of apple. The effect of five constant temperatures (13.3, 15.3, 20.7, 26.1, and 30.0°C) on the demography of P. ringoniella was examined and the data were analyzed by life table parameters using jackknife technique. Developmental period of immatures (25.9–76.4d) showed significant negative relationship to the temperatures with high temperature inhibition at 30°C. Immature survival was highest at 20.7°C and lowest at 30.0°C. Temperature did not affect the 1:1 female:male ratio. Adult females lived longer (18.6d) and produced highest number of eggs (94.0/female) at 15.3°C but lived shorter (5.4d) and produced least eggs (13.6/female) at 30.0°C. Population growth parameters of net reproductive rate (R0), intrinsic rate of increase (r), and finite rate of increase (λ) were higher at 20.7°C. Mean generation time (T) decreased from 85.2 to 30.5d as temperature increased from 13.3 to 30°C, while the population doubling time (DT) was shortest (10.7d) at 20.7°C. This is the first detailed report on the demographic biology of P. ringoniella, and could facilitate the understanding of population dynamics and could help in decision making for P. ringoniella management in apple orchards.