Search results for "plastic"
showing 10 items of 7296 documents
Effect of the extensional flow on the properties of oriented nanocomposite films for twist wrapping
2011
In this study, we examined the mechanical behavior of nanocomposite films based on polyethylene (PE) and pristine PE films. The films were prepared by film blowing and were then cold-drawn at low temperature. The experimental results show that cold drawing significantly enhanced the orientation; with increasing draw ratio (DR), the elastic modulus and tensile strength of the PE films strongly increased, particularly in the presence of the organoclay. To obtain polymeric films suitable for twist wrapping, the films must be sufficiently stiff so that no shrinkage or elastic recovery occur during or after twisting. The elongation at break and the yield strain sharply decreased with orientation…
Predator-Induced Plasticity on Warning Signal and Larval Life-History Traits of the Aposematic Wood Tiger Moth, Arctia plantaginis
2021
Correction Frontiers in Ecology and Evolution Volume 9 Article Number 737651 DOI 10.3389/fevo.2021.737651 Published JUL 29 2021 Predator-induced plasticity in life-history and antipredator traits during the larval period has been extensively studied in organisms with complex life-histories. However, it is unclear whether different levels of predation could induce warning signals in aposematic organisms. Here, we investigated whether predator-simulated handling affects warning coloration and life-history traits in the aposematic wood tiger moth larva, Arctia plantaginis. As juveniles, a larger orange patch on an otherwise black body signifies a more efficient warning signal against predators…
Appearance before performance? : Nutritional constraints on life‐history traits, but not warning signal expression in aposematic moths
2020
1.Trade‐offs have been shown to play an important role in the divergence of mating strategies and sexual ornamentation, but their importance in explaining warning signal diversity has received less attention. In aposematic organisms, allocation costs of producing the conspicuous warning signal pigmentation under nutritional stress could potentially trade‐off with life‐history traits and maintain variation in warning colouration. 2. We studied this with an aposematic herbivore Arctia plantaginis (Arctiidae), whose larvae and adults show extensive variation in aposematic colouration. In larvae, less melanic colouration (i.e. larger orange patterns) produces a more efficient warning signal aga…
Antibacterial activity and cytotoxicity of selected Egyptian medicinal plants.
2011
Medicinal plants have been used as a source of remedies since ancient times in Egypt. The present study was designed to investigate the antibacterial activity and the cytotoxicity of the organic extracts from 16 selected medicinal plants of Egypt. The study was also extended to the isolation of the antiproliferative compound jaeschkeanadiol p-hydroxybenzoate (FH-25) from Ferula hermonis. The microbroth dilution was used to determine the minimal inhibitory concentration (MIC) of the samples against twelve bacterial strains belonging to four species, Providencia stuartii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, while a resazurin assay was used to assess the cytoto…
Short-term responses of Rana arvalis tadpoles to pH and predator stress: adaptive divergence in behavioural and physiological plasticity?
2022
Environmental stress is a major driver of ecological and evolutionary processes in nature. To cope with stress, organisms can adjust through phenotypic plasticity and/or adapt through genetic change. Here, we compared short-term behavioural (activity) and physiological (corticosterone levels, CORT) responses of Rana arvalis tadpoles from two divergent populations (acid origin, AOP, versus neutral origin, NOP) to acid and predator stress. Tadpoles were initially reared in benign conditions at pH 7 and then exposed to a combination of two pH (acid versus neutral) and two predator cue (predator cue versus no predator cue) treatments. We assessed behavioural activity within the first 15 min, an…
Antiviral prophylaxis in patients with haematological malignancies and solid tumours: Guidelines of the Infectious Diseases Working Party (AGIHO) of …
2006
Morbidity and mortality in patients with malignancies are increased by viral infections. These mostly are reactivations of asymptomatic latent infections. They primarily concern clinical entities associated with the reactivation of herpes viruses, such as varicella zoster virus (VZV) and cytomegalovirus (CMV). Respiratory tract infections caused by influenza, parainfluenza or respiratory syncytial virus (RSV) are less common. Since reactivation of latent infections has major clinical impact, antiviral prophylaxis is an attractive approach for patients expecting immunosuppression. The main risk factor for clinically relevant reactivation is profound disruption of cellular immune response. Du…
Electrical conductivity of glass fiber-reinforced plastic with nanomodified matrix for damage diagnostic
2021
The electrical conductivity of glass fiber-reinforced plastic (GFRP) with epoxy matrix modified by multiwall carbon nanotubes (MWCNT) was studied. The electrical conductivity of nanomodified lamina and multi-layered GFRP was investigated on several levels using a structural approach. Components of the electrical conductivity tensor for unidirectional-reinforced monolayer were calculated similarly as in micromechanics using the conductivity of the nanomodified matrix. The electrical conductivity of multilayer composite was calculated using laminate theory and compared with values measured experimentally for various fiber orientation angles. Calculated and experimental data were in good agree…
Vascularized dermal flap for abdominal wall reconstruction after bariatric surgery
2009
WASTE PLASTICS MANAGEMENT IN MUNICIPALITIES: LOGISTICS AND PROCESSES IN LOMBARDIA (NORTHERN ITALY)
2013
A partnership of 49 Municipalities lying in Lombardia (Northern Italy) and belonging to the District “Monza and Brianza” has entrusted the management of the Municipal Solid Waste (MSW) to two Public Companies: “C.E.M. Ambiente S.p.A.” - which owns and operates a transfer station and a multi-material centre - and “SERUSO S.p.A.”, whose single facility is set up and equipped for a high performance factory sorting of the dry fraction of the urban waste. The catchment area is populated by 448 000, living in an area of 366 km2. The management system starts with household sorting for multi-bin curbside collection; followed by hauling to selection and physical treatment facilities; and last, trans…
Particle balance and return loops for microplastics in a tertiary-level wastewater treatment plant.
2021
Highlights: Dewatering by centrifugation was a step that removed a high number of MPs from the sludge. Sludge retained especially the fibrous microplactics. Reject water transported microplastics inside a wastewater treatment plant. Disc filter-based tertiary treatment ensured removal of 99% of microplastics in wastewater. Microplastics (MPs) from households, stormwater, and various industries are transported to wastewater treatment plants (WWTPs), where a high proportion of them are captured before discharging their residuals to watersheds. Although recent studies have indicated that the removed MPs are mainly retained in wastewater sludge, sludge treatment processes have gained less atten…