137 research outputs found
Feasibility Study for the Fuel Switch of a Fast Ferry
No full textLiquefied Natural Gas (LNG) has recently become a popular fuel in the
shipping industry due to its low emissions and high energy density. However, it
requires one or more bulky cryogenic tanks for storage onboard. Considering a
traditional fast ferry, it is hard to find onboard a location for tanks, thus hindering
the retrofit of existing ships. In this context, Compressed Natural Gas (CNG) might
be a viable solution, since it can be more flexibly stored onboard and has greater
availability in minor ports compared to LNG. Hence, this article investigates the
feasibility ofretrofitting the propulsion system of a fast ferry to employ CNG as fuel.
After a review of the pros and cons of CNG and LNG as alternative fuels to marine
diesel oil (MDO), a critical analysis of the technical requirements for retrofitting a
fast ferry with CNG propulsion systems is carried out. Defined the layout and
changes of the refitted unit, its performances are assessed on atest operative scenario.
The study concludes that CNG retrofitting is technically feasible and provides
several benefits, including lower emissions, higher levels of performance and higher
reliability compared to LNG. Nevertheless, the retrofit requires significant changes
to the ship layout and its fuel system to fit the required number of CNG cylinders
A Methodology for Predicting Vertical Motions in Ship Concept Design
No full textThe seakeeping performance of a ship is one of the primary characteristics to be considered during the design phase to determine the ship’s response in irregular sea conditions. The ship’s main geometric parameters must be selected in the very early stages of design as they influence the seakeeping performance, ensuring compliance with the operational conditions specified by the shipowner. In particular, for cruise ships, it is essential to evaluate the vertical motions to provide comfort for the passengers. It is intended to propose a statistical methodology for calculating the vertical motions of a cruise ship without employing complex theories such as strip theory, which are dependent on hull forms that are still unknown during the concept design phase. The methodology is based on calculating the Root Mean Square (RMS) of heave and pitch motions in various sea states and ship speeds through Multiple Linear Regressions (MLR), using a database of cruise ships created with the design of experiment (DoE) techniques by varying significant geometric parameters affecting seakeeping performance
Samuele R. Bacchiocchi and Family
No full textSeventh-day Adventist author and theologian, Samuele R. Bacchiocchi and his wife and their children at a graduation ceremony at Pontifical University
Application of next generation semiconductor based sequencing to detect the botanical composition of monofloral, polyfloral and honeydew honey
No full textHoney is one of the most frauded food products. Therefore, it is important to develop new analytical systems useful for its authentication. Honey contains intrinsic markers that can be used to identify and monitor its origin, including plant DNA mainly derived by pollen. In this study, we applied a next generation sequencing approach for honey authentication by detecting the prevalent botanical contribution and botanical composition of honeys of different origin. DNA was isolated from nine honeys (six monofloral honeys produced in Italy, two polyfloral honeys produced in East Europe and Chile respectively, and one honeydew honey) and PCR amplified for a chloroplast trnL barcoding fragment. Obtained amplicons were sequenced using the Ion Torrent sequencing platform. Sequence data was interpreted using a customized bioinformatic pipeline that used a reference plant sequence dataset derived by more than 150,000 entries. A total of 254 botanical groups were identified from the nine analysed samples, ranging from 37 groups in orange tree blossom honey to 74 in eucalyptus tree blossom honey. The prevalent expected botanical origin was confirmed in five out of six monofloral honeys. The plant signature of the labelled lime tree blossom honey did not confirm the expected botanical prevalence. The most represented botanical group in the honeydew honey was Castanea. The botanical composition of monofloral and polyfloral honey samples was useful to infer their geographical origin. The metabarcoding based system applied in this study captured the botanical signature of all analysed honey samples and provided information useful for their authentication
ENVIRONMENTAL DNA IN HONEY: GENOMIC TOOLS FOR ENTOMOLOGICAL AUTHENTICATION OF THIS PRODUCT.
No full textHoney is one of the most commonly frauded food products, with the most frequent frauds involving adulteration and mislabeling of its origin. The entomological origin of honey can be considered from two perspectives: i) the subspecies of Apis mellifera that produced the honey; and ii) the footprints derived from plant-suckling insects that produce honeydew, which are always present in authentic honey. Identifying the A. mellifera subspecies provides an important link to boost the conservation and integrity of honeybee populations and also offer indirect information on the geographic origin of the honey, based on the natural distribution of the different subspecies.
Plant-suckling insects belonging to the Rhynchota order provide multidimensional information related to the plant origin of honeydew, based on the botanical specialization of these plant parasites, indirectly indicating the geographic origin of the honey. To identify the honey bee subspecies, we set up assays to analyse DNA extracted from honey that targeted regions of the A. mellifera mitochondrial DNA (mtDNA). These regions are informative to distinguishing different subspecies carrying the mtDNA lineages A (e.g. A. m. siciliana) and M (e.g. A. m. mellifera), as well haplotypes C1 (A. m. ligustica) and C2 (A. m. carnica). Another assay was designed to genotype approximately100 subspecies-informative honey bee single nucleotide polymorphisms (SNPs) using DNA extracted from honey and a genotyping-by-sequencing approach. For identifying plantsuckling insects, we designed a targeted metabarcoding assay based on two conserved regions of Rhynchota mtDNA using a next generation sequencing approach, along with bioinformatic pipelines to interpret sequenced reads and assign them to Rhynchota families. These approaches were applied to more than 150 honey samples, revealing that these methods are highly informative for authenticating the honey based on their entomological origin
Genotyping-by-sequencing of honey derived environmental DNA can retrieve information on the Apis mellifera subspecie.
No full textHoney contains environmental DNA (eDNA) traces derived from all organisms that directly or indirectly contributed to its production or that have been part of the production niche and environment from which this matrix is obtained. We recently demonstrated that honey constitutes an easily accessible source of Apis mellifera DNA useful to retrieve population genetic information. We also recently demonstrated that honey bee mitochondrial DNA (mtDNA) specific lineages detected in the honey can be used to authenticate the entomological origin of the honey. In this study we analysed honey DNA and integrated honey bee mtDNA information with nuclear genome polymorphisms to set up an improved tool that can detect the honey bee subspecies using these two genome levels. To this aim, we designed and tested a genotyping by sequencing (GBS) assay to analyse 121 single nucleotide polymorphisms (SNPs) of A. mellifera nuclear genome using eDNA extracted from honey. Results were integrated with information derived from previous studies and whole genome resequencing datasets. Genomic analyses were obtained for 61 specimens (honey samples and honey bees) collected in a few Italian regions (Emilia-Romagna, Liguria and Sicily) and that included: (i) individual honey bees of the subspecies A. m. ligustica, A. m. mellifera and A. m. siciliana; (ii) groups of pooled DNA samples from more than 30 A. m. ligustica workers belonging to the same colonies from which honey samples (see below) have been collected; (iii) honey samples obtained from 32 single hives; (iv) undifferentiated honey samples produced from A. m. ligustica and A. m. siciliana. The GBS runs produced more than 53 million reads that were used to obtain genotype information of the selected bi-allelic SNPs. Allele frequency estimation combined with several multidimensional scaling approaches were able to 25th Congress of Animal Science and Production Associationcorrectly assign the honey to the honey bee subspecies that produced it with high correlations between samples and runs. Overall, results obtained from GBS demonstrated the possibility to use A. mellifera nuclear genome variability to authenticate the entomological origin of the honey by detecting the honey bee subspecies.
Acknowledgements
This study was supported by Regione Emilia Romagna – BEE-RER3
projec
Fast Estimation of the Time-to-Flood on Simple Geometries
No full textTime-to-flood is a key parameter
during a flooding emergency. Especially in complex geometries, it is important
to know the time needed to fill the first flooded room, i.e., the damaged
one. Here, a fast solution for the assessment of the time-to-flood of one or two
parallelepiped rooms is proposed. The progressive flooding of the rooms is first
simulated employing a linearised simulation technique that defines a database of
damage cases covering a wide range of geometries. Explicit equations are then defined
based on the main non-dimensional parameters governing the phenomenon.
The work highlights the relationship between the geometry of a room, the damage
opening, the connection opening, and the time to fill the first damaged room. The
application of the equations is very fast and provides an instantaneous estimation
of the time-to-flood. This makes them particularly suitable for direct application on
board or when creating large datasets of flooding simulations
A genotyping by sequencing approach can disclose Apis mellifera population genomic information contained in honey environmental DNA
No full textAwareness has been raised over the last years on the genetic integrity of autochthonous honey bee subspecies. Genomic tools available in Apis mellifera can make it possible to measure this information by targeting individual honey bee DNA. Honey contains DNA traces from all organisms that contributed or were involved in its production steps, including the honey bees of the colony. In this study, we designed and tested a genotyping by sequencing (GBS) assay to analyse single nucleotide polymorphisms (SNPs) of A. mellifera nuclear genome using environmental DNA extracted from honey. A total of 121 SNPs (97 SNPs informative for honey bee subspecies identification and 24 SNPs associated with relevant traits of the colonies) were used in the assay to genotype honey DNA, which derives from thousands of honey bees. Results were integrated with information derived from previous studies and whole genome resequencing datasets. This GBS method is highly reliable in estimating honey bee SNP allele frequencies of the whole colony from which the honey derived. This assay can be used to identify the honey bee subspecies of the colony that produced the honey and, in turn, to authenticate the entomological origin of the honey
Entomological signatures in honey: an environmental DNA metabarcoding approach can disclose information on plant-sucking insects in agricultural and forest landscapes
No full textHoneydew produced from the excretion of plant-sucking insects (order Hemiptera) is a carbohydrate-rich material that is foraged by honey bees to integrate their diets. In this study, we used DNA extracted from honey as a source of environmental DNA to disclose its entomological signature determined by honeydew producing Hemiptera that was recovered not only from honeydew honey but also from blossom honey. We designed PCR primers that amplified a fragment of mitochondrial cytochrome c oxidase subunit 1(COI) gene of Hemiptera species using DNA isolated from unifloral, polyfloral and honeydew honeys. Ion Torrent next generation sequencing metabarcoding data analysis assigned Hemiptera species using a customized bioinformatic pipeline. The forest honeydew honeys reported the presence of high abundance of Cinara pectinatae DNA, confirming their silver fir forest origin. In all other honeys, most of the sequenced reads were from the planthopper Metcalfa pruinosa for which it was possible to evaluate the frequency of different mitotypes. Aphids of other species were identified from honeys of different geographical and botanical origins. This unique entomological signature derived by environmental DNA contained in honey opens new applications for honey authentication and to disclose and monitor the ecology of plant-sucking insects in agricultural and forest landscapes
sd920/FIJI-macros-for-IHC-and-SHG-analysis: Batch Split Channels (3 channels)
No full textThis macro allows to split channels for Z-stack .tiff files and save them in a new folder in batch mode.
Author: Samuele Di Carmine, [email protected]
Version 1.0
July 13, 2021
//License: BSD3
Copyright 2021 Samuele Di Carmine, Imperial College Londo
- …
