Search results for "Nile"
showing 10 items of 619 documents
Reproductive monopoly enforced by sterile police workers in a queenless ant
2004
In societies of totipotent insects, dyadic dominance interactions generate a hierarchy that often underlies an extreme reproductive skew. Subordinates remain infertile but can maximize their indirect fitness benefits through collective power (worker policing): interference with challenging high-rankers can prevent an untimely replacement of the reproductive. However, police workers only benefit if they favor individuals with high fertility. In the monogynous queenless ant Streblognathus peetersi, we used behavioral, physiological, and chemical methods to show that police workers have the primary role in the selection of the reproductive, and that they probably use reliable information about…
Boldness-exploration behavioral syndrome: interfamily variability and repeatability of personality traits in the young of the convict cichlid (Amatit…
2015
9 pages; International audience; In recent years, considerable research interest in behavioral ecology has focused on characterizing and understanding individual differences in behavior that are consistent over time and across contexts, termed animal “personalities,” and correlations between various behaviors across contexts, termed behavioral syndromes. Although there is some evidence that differences in personality among individuals within populations can be genetically based and adaptive, when and how individual personality differences emerge in a population is not well understood, but of considerable general interest. Here, using juveniles of the convict cichlid (Amatitlania siquia) as …
Density dependence of infanticide and recognition of pup sex in male bank voles
2010
[Infanticide — the killing of conspecific young — is a common phenomenon in many invertebrate and vertebrate species, particularly common in rodents. It can increase juvenile mortality and, thus, affect population growth. Male infanticide is explained by adaptive hypotheses based on sexual selection. Removing future competitors for mating opportunities would require recognition of pup sex and directing infanticide against male pups. We studied whether the sex of a pup and population density affect male bank voles' ( Myodes glareolus ) aggressive behaviour towards conspecific pups. Population density increased aggressiveness. Against our predictions, male bank voles from high density populat…
Toward a mechanistic understanding of vulnerability to hook-and-line fishing: Boldness as the basic target of angling-induced selection
2017
In passively operated fishing gear, boldness-related behaviors should fundamentally affect the vulnerability of individual fish and thus be under fisheries selection. To test this hypothesis, we used juvenile common-garden reared carp (Cyprinus carpio) within a narrow size-range to investigate the mechanistic basis of behavioral selection caused by angling. We focused on one key personality trait (i.e., boldness), measured in groups within ponds, two morphological traits (body-shape and head-shape), and one life-history trait (juvenile growth capacity) and studied mean standardized selection gradients caused by angling. Carp behavior was highly repeatable within ponds. In the short-term, ov…
Heat hardening capacity in Drosophila melanogaster is life stage-specific and juveniles show the highest plasticity
2019
Variations in stress resistance and adaptive plastic responses during ontogeny have rarely been addressed, despite the possibility that differences between life stages can affect species' range margins and thermal tolerance. Here, we assessed the thermal sensitivity and hardening capacity of Drosophila melanogaster across developmental stages from larval to the adult stage. We observed strong differences between life stages in heat resistance, with adults being most heat resistant followed by puparia , pupae and larvae . The impact of heat hardening (1 h at 35°C) on heat resistance changed during ontogeny, with the highest positive effect of hardening observed in puparia and pupae and the …
Anakinra drug retention rate and predictive factors of long-term response in systemic juvenile idiopathic arthritis and adult onset still disease
2019
Background and Objective: Only a few studies have reported long-term efficacy of interleukin (IL)-1 inhibition in systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still disease (AOSD). Herein we report on the effectiveness of anakinra (ANA), expressed in terms of drug retention rate (DRR), and evaluate the predictive factors of drug survival in a cohort of patients with sJIA and AOSD. Patients and Methods: This is a multicenter study reviewing retrospectively the medical records from 61 patients with sJIA and 76 with AOSD, all treated with ANA in 25 Italian tertiary referral centers. Results: The cumulative retention rate of ANA at 12-, 24-, 48-, and 60-month of follow-up was 7…
Prediction of unfavorable outcomes in West Nile virus neuroinvasive infection - Result of a multinational ID-IRI study
2019
Background: WNV causes 1.4% of all central nervous system infections and is the most common cause of epidemic neuro-invasive disease in humans. Objectives: Our main objective was to investigate retrospectively West Nile virus neuroinvasive disease (WNND) cases hospitalized during 2010–2017 and identified factors that can influence prognosis. Study design: We documented the demographic, epidemiologic, clinical and laboratory data of WNND and identified factors that can influence prognosis. The data were recruited through Infectious Diseases International Research Initiative (ID-IRI), which serves as a network for clinical researches. Results: We investigated 165 patients with WNND in 10 coun…
The Role of Chemokines in Alzheimer's Disease
2019
Objective: The most common multifactorial neurodegenerative disorder occurring in old age is Alzheimer’s disease. The neuropathological hallmarks of that disorder are amyloid plaques with the presence of β -amyloid aggregates, intraneuronal tau protein tangles, and chronic inflammation. Brain cells such as microglia and astrocytes are inflammatory cells associated with Alzheimer’s disease and involved in the production of inflammatory mediators, such as cytokines and chemokines. Chemokines consist of a large family of protein mediators with low molecular weight, which able to control the migration and residence of all immune cells. In pathological conditions, such as Alzheimer’s disease, c…
Replacement of fishmeal with corn gluten meal in feeds for juvenile rainbow trout (Oncorhynchus mykiss) does not affect oxygen consumption during for…
2017
Abstract We compared oxygen consumption (MO 2 , mg/kg/h) of c. 80 g rainbow trout ( Oncorhynchus mykiss ) in an intermittent-flow swim respirometer at 15 °C. Before the tests the fish were grown in flow through tanks (15 °C) with either fishmeal (FM) or corn gluten meal (CGM) based diets (c. 52% protein) for a period of 3–4.5 months. Ten individuals from both treatment groups were fasted for 48 h before the swim test, which consisted of 18 loops of 210 s over three different periods: acclimation period (6 loops at 0.5 body lengths per s, BL/s), exercise period (8 loops at increased speed from 1 to 2.5 BL/s with recovery loops at 0.5 BL/s), and a recovery period (four loops at 0.5 BL/s). We …
Drug Retention Rate and Predictive Factors of Drug Survival for Interleukin-1 Inhibitors in Systemic Juvenile Idiopathic Arthritis.
2019
Introduction: The advent of biologic agents has revolutionized therapeutic approaches in systemic juvenile idiopatic arthritis (sJIA) as their introduction has been shown to modify disease course and improve overall outcomes, particularly when initiated early. Few studies have reported the drug retention rate (DRR) of biologic drugs in JIA, and none of them has specifically investigated the DRR of interleukin (IL)-1 inhibitors on sJIA. Objectives: The primary aim of the study was to examine the overall DRR of IL-1 blockers in sJIA patients. Secondary aims of our study were to: (i) explore the influence of biologic line of treatment, adverse events (AEs), type of anti-IL-1 agent and the conc…