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Mitten Impossible: investigating the use of environmental DNA (eDNA) as a detection tool for Chinese Mitten Crab Eriocheir sinensis
No full textInvasive Alien Species (IAS) are considered a key threat to global biodiversity. Environmental DNA (eDNA) sampling has emerged as a valuable tool for IAS detection and surveillance. The Chinese Mitten Crab (Eriocheir sinensis) is a high-risk IAS that can tolerate both fresh and salt water due to its catadromous life cycle. The Marine Institute (Ireland) began testing for E. sinensis DNA when monitoring for possible vectors of crayfish plague. Several TaqMan assays have been trialled for detecting E. sinensis, two of which have been used successfully in other countries (Canada and Denmark). Whilst several live specimens have been caught in Waterford Harbour since 2006, no E. sinensis DNA has been detected in Irish waters to-date. To evaluate reasons for these negative results, research was undertaken to investigate if the salinity of water influences the eDNA shedding and persistence of this species. Sensitivity testing was carried out on the two species-specific assays currently used by the Marine Institute for E. sinensis detection. Shedding and decay rates were determined through a series of tank trials, whereby a single female Chinese Mitten crab was placed in a fresh or brackish water tank for a number of hours. Assay sensitivity was determined using synthetic target DNA (gBlock). We found that DNA shedding rate was six times higher in brackish than freshwaters (DNA shedding= 3.12x10-6 vs 6.42x10−7 DNA copies/μL/hour). eDNA decay exhibited expected exponential degradation at both salinities. Decay constants were 0.108hr-1 (brackish) and 0.045hr-1(fresh water). The Danish assay (Knudsen et al., (2019) was more sensitive than the Canadian (Chevrinais et al., (2023), with the ability to detect DNA concentration as low as 106.6 DNA copies/μL, in comparison to 192.5 DNA copies/μL. Our results indicate that salinity could affect eDNA detection of E. sinensis, with a higher chance of detection in brackish waters. The results of this study will be used to inform management of E. sinensis in Ireland, by indicating priority locations to sample (based on salinity) and maximise DNA amplification (by using Danish assay)
Hollywood: the Family of Man
No full textRapporto tra il cinema classico hollywoodiano e l'umanesimo fotografic
Alcune dinamiche del sistema artistico attraverso i fondi storici del Monte di Pietà
No full textIl testo ricostruisce il ruolo del Monte di Pietà di Roma nella gestione, valutazione e circolazione delle opere d’arte tra XVIII e XIX secolo. L’istituto, dotato di un rigido codice deontologico, mantenne sempre alta l’attenzione verso le potenziali irregolarità legate alla custodia e al pegno di beni artistici, pur registrando episodiche trasgressioni da parte del personale. Particolare rilievo assume la figura del cassiere Lorenzo Toma, che nel Settecento sfruttò la conoscenza del patrimonio custodito per attività speculative e per ampliare la propria collezione privata. Il caso più significativo riguarda però il marchese Giovan Pietro Campana, direttore del Monte dal 1833, la cui intensa attività collezionistica — alimentata dalla sua posizione istituzionale — portò alla formazione del celebre Museo Campana, successivamente oggetto di confisca e disperso tra musei europei e americani. Dopo il 1870, con l’ingresso del patrimonio del Monte nel quadro amministrativo dello Stato unitario, le opere ritenute di minor valore furono immesse sul mercato, mentre quelle di maggior pregio contribuirono a definire l’immagine internazionale dell’arte italiana.The text examines the role of the Monte di Pietà of Rome in the management, appraisal, and circulation of works of art from the eighteenth to the nineteenth century. The institution, governed by a strict ethical code, consistently guarded against misconduct related to the custody and pledging of artworks, although occasional transgressions by staff members did occur. A significant figure is the cashier Lorenzo Toma, who in the eighteenth century exploited his access to the institution’s holdings for speculative purposes and to expand his personal collection. The most consequential case, however, concerns Marquis Giovan Pietro Campana, appointed director in 1833, whose remarkable collecting activity—supported by his institutional position—led to the creation of the renowned Campana Museum. Following his dramatic fall and the confiscation of his assets, the collection was dispersed among European and American museums. After 1870, when the Monte di Pietà’s artistic assets were absorbed into the administrative framework of the newly unified Italian state, works deemed of lesser importance entered the market, while those of higher quality contributed to shaping the international image of Italian art
Optimization of Parallel Artificial Liquid Membrane Extraction for the Determination of Over 50 Psychoactive Substances in Oral Fluid Through UHPLC–MS/MS
No full textOver the past decade, there has been a diversification of the psychoactive substances available among drug users, resulting in the expansion of a dynamic market of synthetic molecules that are challenging for drug of abuse testing. Multiclass analytical methods are useful to deal with these new psychoactive substances (NPS), but sample preparation can be difficult and generate significant amounts of chemical waste. The aim of this work was the development of a high-throughput microextraction method for the determination of 56 drugs belonging to different pharmacological classes in oral fluid (OF), including both traditional drugs and NPS. In the proposed workflow, the OF sample is cleaned-up by parallel artificial liquid membrane extraction (PALME) and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two hundred microliters of OF are mixed with 1800 mu L of carbonate buffer 0.5 M (pH 12) and 0.4 g of sodium chloride and inserted into a donor plate; the acceptor plate embed a dodecylacetate-supported liquid membrane and an acceptor solution composed of 50 mu L formic acid 0.1% in H2O: MeOH, 80:20 (v/v); the whole assemblage is placed on an orbital shaker for 120 min for extraction. A full factorial design has been employed for extraction optimization to make it suitable for LC-MS/MS. The developed method is an example of green chemistry and may be used for screening and quantitative purposes, with limits of detection ranging from 0.01 to 1.5 ng mL-1 and optimal performance in term of precision and accuracy for 49 out of 56 drugs tested
