Search results for "Life cycle"

Insight into the role of cetaceans in the life cycle of the tetraphyllideans (Platyhelminthes: Cestoda)

2007

Abstract Four types of tetraphyllidean larvae infect cetaceans worldwide: two plerocercoids differing in size, ‘small’ (SP) and ‘large’ (LP), and two merocercoids referred to as Phyllobothrium delphini and Monorygma grimaldii . The latter merocercoid larvae parasitize marine mammals exclusively and exhibit a specialised cystic structure. Adult stages are unknown for any of the larvae and thus the role of cetaceans in the life cycle of these species has been a long-standing problem. The SP and LP forms are thought to be earlier stages of P. delphini and M. grimaldii that are presumed to infect large pelagic sharks that feed on cetaceans. A molecular analysis of the D2 variable region of the …

Classification of Spanish Mosquitoes in Functional Groups

2011

Abstract We present a classification of Spanish mosquitoes according to their different life cycles. The bio-ecological parameters analyzed in our study were oviposition sites, overwintering stages, preferred hosts, and number of generations per year for each species. The results revealed 13 different functional groups. To assess the validity and robustness of the classification system, we analyzed the data from an intensive sampling carried out over a period of 4 years (2005–08) in eastern Spain. In this area, 9 of the 13 functional groups were found. The Jaccard cluster and the principal components analysis (between-group analysis method) revealed 3 different mosquito groups: the tree hol…

Host-manipulation by parasites with complex life cycles: adaptive or not?

2010

7 pages; International audience; The effect of host manipulation by parasites on trophic transmission to final hosts remains unclear. The transmission benefits gained by manipulative parasites are difficult to assess, and evidence for a causal link between manipulation and trophic transmission is missing. In addition, infected intermediate hosts can also be more vulnerable to predation by nonhosts, whereas recent theoretical advances indicate that the evolution of host manipulation does not require increased specificity in trophic transmission. We propose that a deeper consideration of the evolution of complex life cycles in helminth parasites might provide a different perspective on the ev…

Mediterranean Diplodus annularis (Teleostei: Sparidae) and its brain parasite: Unforeseen outcome

2005

Patterns of parasite load and aggregation of the bird trematode Cardiocephaloides longicollis in its main intermediate host in the Mediterranean, the annular sea bream, Diplodus annularis, were studied in a large sample collected off Valencia (Spain) and are discussed within the context of the parasite induced host mortality hypothesis. The metacercariae were located within large composite cysts of host origin in the ventricles of the optic lobes of the cerebrum. A weak immunological response was detected in older fish, which was significantly associated with the total parasite load. Although the mean abundance of C. longicollis showed a tendency to increase with host size, the infection le…

Approccio “Life Cycle Thinking” applicato alla riparazione di una scuola danneggiata dal terremoto dell’Italia centrale

2017

L’adeguamento sismico ed il miglioramento energetico delle strutture sono diventati al giorno d’oggi una priorità. Buona parte del patrimonio edilizio esistente si trova in stato di grande obsolescenza strutturale, architettonica ed energetica. Oltre alla prevenzione, tuttavia, un aspetto molto importante riguarda la riparazione e riqualificazione degli edifici resi inagibili dagli eventi sismici recentemente accaduti nel territorio nazionale. In modo particolare, nel presente articolo verrà preso in considerazione un edificio del plesso scolastico sito nel Comune di Pievebovigliana, provincia di Macerata, danneggiato dai terremoti che hanno colpito l’Italia centrale il 24.08.2016 e il 30.1…

A bug's life: Delving into the challenges of helminth microbiome studies.

2020

The body of vertebrates is inhabited by trillions of microorganisms, i.e. viruses, archaea, bacteria and unicellular eukaryotes, together referred to as the ‘microbiota’. Similarly, vertebrates also host a plethora of parasitic worms (the ‘macrobiota’), some of which share their environment with the microbiota inhabiting the gastrointestinal tract [1]. Complex interactions between the helminths and the gut microbiota have been associated with establishment of parasite infection, disease manifestations, and host immune-modulation [2, 3]. Remarkably, not only enteric helminths alter the 26 gut microbiome composition [4], but also the infection with blood flukes of the genus Schistosoma has be…

Environmental assessment of a waste-to-energy practice: The pyrolysis of agro-industrial biomass residues

2021

Abstract The bio-wastes pyrolysis is a waste to energy strategy that converts bio-wastes into valuable products (bio-char, bio-oil) with wide use in the agri-food sector. However, limited efforts are paid to the investigation of its environmental sustainability: in this context, the study contributes the need towards the assessment of a wide range of environmental impacts for the pyrolysis process of different types of bio-wastes under different operating conditions. The study estimates the potential environmental impacts related to bio-char production from the pyrolysis of several different agro-industrial residues and different temperatures and identifies the process “hot spots”. The anal…

Uncertainty analysis of life cycle assessment of asphalt surfacings

2023

The Life Cycle Assessment (LCA) of asphalt pavements are associated with significant uncertainty resulting from variability in the quantity and impact of individual components, the quality of data for each component, and variability of asphalt durability. This study presents a framework to quantify and incorporate the uncertainty of LCA and asphalt durability data into LCA of asphalt surfacings. The suggested framework includes: estimating the uncertainty of asphalt production processes by the pedigree matrix method, conducting a deterministic LCA, applying Monte Carlo Simulation (MCS) to estimate the probability density functions (PDFs) of the considered impacts using the uncertainty data,…

ENVIRONMENTAL IMPACT OF BIO-BASED ASPHALT MIXTURES: LIFE CYCLE INVENTORY, LIFE CYCLE ASSESSMENT AND RECOMMENDATIONS

A critical review of life cycle assessment benchmarking methodologies for construction materials

2022

As it stands, the construction sector accounts for a significant proportion of global emissions. The majority of these emissions can be associated with material production. As a result, the importance of quantifying these environmental impacts is continually increasing. However, there is a current lack of guidance and methodologies regarding how to benchmark the impacts of construction products, and thus achieve more transparent environmental reporting and decision-making. Therefore, the aim of this study was to review engineering life-cycle assessment (LCA) literature and applicable standards to identify the key methodological variables required and the key steps for a sector-wide methodol…