280 research outputs found
Phylogeny and biogeography of pholadid bivalve Barnea (Anchomasa) with considerations on the phylogeny of Pholadoidea
No full textThe paper examines the systematics, phylogeny and biogeographical history of Barnea (Anchomasa), which is one of the most abundant and diversified of modern pholadid bivalves. The range of morphology of its distinctive characters and comparisons with other pholadoidean taxa are described in detail. An extensive cladistic analysis based on morphological characters at genus and subgenus levels allowed the inclusion of B. (Anchomasa) into the phylogeny of Pholadoidea and the establishment of its most appropriate taxonomic position. The analysis confirms that Barnea s.s. and B. (Umitakea) are its closest relatives and that the morphological similarities to other taxa are mainly due to plesiomorphies. The fossil record and the data on the present−day distribution contributed to trace the biogeographical history of B. (Anchomasa). The present−day biogeography is marked by the disjunct distribution of species. Species are distributed mainly either along the Atlantic and Pacific coasts of the American continent (American group) or in the Indo−West Pacific region (Indo−West Pacific group). Both these groups have distinct morphological features and biogeographical structures. The fossil record and the known geodynamic scenario suggest a relationship of direct derivation between the Indo−West Pacific group and a stock of north−eastern Atlantic to Paratethyan species. This reflects a vicariant event related to the closure of the connection between western Tethys and the Indian Ocean in the middle Miocene. The American group presumably arose from the European stock during the Late Pliocene by dispersal towards the eastern coasts of North America and rapid southward diffusion. A relative differentiation within the American group is probably related to the last phases of emergence of the Panama Isthmus. The cladistic analysis also gives suggestions for the reconstruction of the phylogeny of the superfamily Pholadoidea. It confirms the interpretation of several characters sustained by previous authors. However, it also shows remarkable differences to the previous taxonomic arrangements. Pholadinae includes only taxa having the protoplax and it appears to be the sister−group of a major clade composed mainly of two groups, namely Martesiinae–Jouannetiinae and Xylophagainae–Teredinidae. The Martesiinae are paraphyletic whereas the obligate wood−boring Xylophagainae and Teredinidae form a well−supported monophyletic group
The genus Leptomaria E Eudes-Deslongchamps, 1864 (Gastropoda, Pleurotomariidae) from the Early Bajocian of Luxembourg: systematics and paleobiogeography.
No full textFour species of the pleurotomariid genus Leptomaria E Eudes-Deslongchamps, 1864 are reviewed based on previously undescribed material from Bajocian deposits of the eastern Paris Basin. One of them, Leptomaria nicsimoni sp. nov., is introduced as a new species. A critical revaluation of the literature shows that Leptomaria has been broadly interpreted in the past, in contrast with the rather detailed description given by its author. This focused on shell characters, such as the width and position of the slit and selenizone, which have been overlooked by most subsequent authors. A revised diagnosis that reintroduces these characters is presented on the basis of the Bajocian material studied and of a survey of the relevant literature. This diagnosis, which is based also on other characters not considered before, excludes from Leptomaria several species previously assigned to it. The genus occurred from the Middle Aalenian to the Cenomanian mainly in the epicontinental seas of western Europe. It experienced a peak of diversity in the Bajocian, followed by a slow decline in Bathonian to Callovian times concomitantly with the appearance of the genus in the south-eastern margin of Tethys. Records in Upper Jurassic to Cretaceous sediments are sparse
Three years of molecular monitoring of phytoplasma spreading in a plumgrowing area in Italy
No full textIn the plum growing area of Vignola (Northern Italy) a molecular monitoring was carried out in order to verify possibility to reduce the epidemic phytoplasma infection. Nucleic acids were extracted from plum leaf midribs for molecular tests to verify phytoplasma presence. Direct PCR using universal primer pairs P1/P7 followed by nested PCR with R16F2/R2 and specific primers R16(X)F1/R1 and RFLP analyses mainly with RsaI and SspI were employed to detect/identify phytoplasmas. The presence of phytoplasma specific DNA bands was observed after nested-PCR using either R16F2/R2 and R16(X)F1/R1 primers. From symptomatic and asymptomatic plum 16SrX-B phytoplasmas were identified. Four farms were monitored during 2000 testing 11 Japanese plum varieties: in June among 40 samples, all from symptomatic plants about 23% were positive in the first nested PCR reaction and 92% in the second one performed with group specific primers 16Sr(X)F1/R1. When the same plants were retested in October, 39 out of the 40 samples were positive in direct PCR. During July 2001 in two of the above farms a total of 57 asymptomatic plums were tested: in the first farm 21% of the plants tested were positive and in the second 17%. In July 2002 both symptomatic and asymptomatic plum were monitored in 3 different fields. Ten out of 20 samples from symptomatic plum resulted to be infected by 16SrX-B phytoplasmas, 5 were negative and in the other samples phytoplasmas belonging to groups 16SrXII-A, 16SrI-B and 16rIII-B were identified. Asymptomatic plant that were re-grafted in 2001 on rootstock where symptomatic scions were previous observed showed that 67% of the plant tested were infected by 16SrX-B phytoplasmas showing a clear evidence that the rootstock was colonized by the pathogens that are able to infect the new grafted scions just during one winter season
PyFuRNAce: an integrated design engine for RNA origami
No full textAbstract Recent developments in medicine and biotechnology have revealed the transformative power of RNA design. To realize the full potential of RNA nanotechnology and RNA origami, user-friendly design tools are needed. Here, we present pyFuRNAce, an open-source, Python-based software package with a graphical user interface that enables the design of complex RNA nanostructures, with particular focus on co-transcriptional RNA origami. PyFuRNAce integrates the entire RNA origami workflow—from motif definition and blueprint design to sequence generation and primer selection—into a single, user-friendly platform. Built around a motif-based assembly paradigm, the software enables users to create and modify custom RNA nanostructures through an intuitive web interface with streamlined design steps and real-time 3D visualization. We use pyFuRNAce to design three distinct RNA nanostructures, including self-assembling RNA filaments, RNA droplets, and the largest co-transcriptional RNA origami to date, consisting of 2501 nucleotides. The structures and their high-yield assembly are validated experimentally with atomic force microscopy and confocal fluorescence imaging. By consolidating multiple design stages into a unified environment, pyFuRNAce broadens the scope and reduces the barrier of entry for RNA nanotechnology, accelerating the development of functional RNA origami structures for applications in medicine, biotechnology, and synthetic biology
Sviluppo di sensori amperometrici per l’analisi in situ di matrici reali. Il caso di studio della Cannabis sativa L.
No full textI sensori elettrochimici sono dispositivi analitici apprezzati per la loro affidabilità, rapidità, facilità d’uso, basso costo e portabilità, caratteristiche che li rendono ideali per analisi in situ. Lo sviluppo di un sensore elettrochimico segue un processo iterativo che inizia con l’analisi del contesto applicativo, passa per la scelta del materiale elettrodico e la definizione delle condizioni di misura, e termina con l’analisi della matrice target.
In questa tesi, si esamina lo sviluppo di un sensore amperometrico per l'analisi dei campioni di Cannabis sativa L., un caso di studio particolarmente rilevante. Esistono vari chemotipi di C. sativa che differiscono per la composizione in cannabinoidi. La C. sativa ricreativa, o marijuana, è ricca di Δ9-tetraidrocannabinolo (Δ9-THC), un composto psicoattivo, mentre la C. sativa da fibra contiene basse quantità di Δ9-THC e alti livelli di cannabidiolo (CBD), non psicoattivo. Normative europee e statunitensi consentono la commercializzazione di prodotti a base di C. sativa solo se il contenuto di Δ9-THC è inferiore allo 0.3 % p/p, rendendo essenziale un controllo accurato dei livelli di questo cannabinoide. In questo studio proponiamo, per la prima volta, un metodo basato sulla sensoristica amperometrica per lo screening rapido delle piante di C. sativa.
Le molecole target identificate per l'analisi elettrochimica sono il Δ9-THC, il CBD e i loro precursori acidi, Δ9-THCA e CBDA, tutte facilmente ossidabili. I test iniziali su soluzioni standard dei singoli cannabinoidi hanno dimostrato l’efficacia degli elettrodi screen-printed modificati con carbon black (SPE-CB) in definite condizioni di misura. Le prestazioni del sensore sono state valutate in condizioni critiche, come la rilevazione di Δ9-THC in presenza di grandi quantità di CBD, problematica frequente nei campioni reali. Data la somiglianza delle risposte voltammetriche di Δ9-THC e CBD, si sono impiegate tecniche multivariate per ottenere le informazioni desiderate. L'analisi elettrochimica dei precursori acidi, caratterizzati da voltammogrammi distinti rispetto alle forme neutre, ha evidenziato l'importanza delle condizioni di misura nel determinare la forma del segnale ottenuto. L'integrazione di tecniche di spettroscopia UV-Vis e di fluorescenza ha ulteriormente arricchito il quadro analitico, aprendo nuove prospettive di ricerca.
Successivamente, lo studio è stato esteso a campioni reali, costituiti da estratti alcolici di C. sativa. Il sensore è stato utilizzato per due obiettivi principali: la quantificazione dei principali cannabinoidi e la rapida identificazione di campioni illegali. Questo ha richiesto l'analisi di numerosi campioni di C. sativa da fibra e ricreativa, impiegando sia approcci univariati che multivariati per l’elaborazione dei dati. È stato sviluppato un metodo per la quantificazione del Δ9-THCA, il cannabinoide principale nelle varietà di C. sativa ricreativa, e costruiti modelli di classificazione in grado di distinguere i campioni legali da quelli illegali sulla base del contenuto di Δ9-THC. In entrambi i casi, i risultati ottenuti sono stati soddisfacenti e in linea con i dati cromatografici.
Infine, è stato sviluppato un prototipo di dispositivo portatile per l'analisi in situ degli estratti di C. sativa, in collaborazione con un gruppo di ricerca di ingegneria. Questo dispositivo automatizza la preparazione della soluzione per l’analisi elettrochimica a partire dal campione vegetale, riducendo al minimo l’intervento dell’operatore. Il sistema integra micropompe, sensori di flusso e una cella elettrochimica in cui è alloggiato l’SPE-CB. I test preliminari hanno confermato l’efficacia del dispositivo, dimostrando che consente un'analisi completa e rapida di campioni vegetali di C. sativa.Electrochemical sensors are analytical devices valued for their reliability, speed, ease of use, low cost, and portability, qualities that make them ideal for in situ analyses. The development of an electrochemical sensor follows an iterative process that begins with the analysis of the application context, proceeds through the selection of electrode material and the definition of measurement conditions, and concludes with the analysis of the target matrix.
In this thesis, the development of an amperometric sensor for the analysis of Cannabis sativa L. samples is examined, a particularly relevant case study. There are various chemotypes of C. sativa that differ in cannabinoid composition. Recreational C. sativa, or marijuana, is rich in Δ9-tetrahydrocannabinol (Δ9-THC), a psychoactive compound, whereas fiber-type C. sativa contains low amounts of Δ9-THC and high levels of cannabidiol (CBD), a non-psychoactive compound. European and U.S. regulations allow the commercialization of C. sativa products only if the Δ9-THC content is below 0.3% w/w, making precise control of this cannabinoid essential. In this study, we propose for the first time a method based on amperometric sensor for the rapid screening of C. sativa plants.
The target molecules identified for electrochemical analysis are Δ9-THC, CBD, and their acidic precursors, Δ9-THCA and CBDA, all of which are easily oxidizable. Initial tests on standard solutions of individual cannabinoids demonstrated the effectiveness of screen-printed electrodes modified with carbon black (SPE-CB) under defined measurement conditions. Sensor performance was evaluated under critical conditions, such as the detection of Δ9-THC in the presence of large amounts of CBD, a common issue in real samples. Given the similarity of the voltammetric responses of Δ9-THC and CBD, multivariate techniques were employed to obtain the desired information. The electrochemical analysis of the acidic precursors, characterized by voltammograms distinct from their neutral forms, highlighted the importance of the measurement conditions in determining the shape of the obtained signal. The integration of UV-Vis spectroscopy and fluorescence techniques further enriched the analytical framework, opening new avenues for research.
Subsequently, the study was extended to real samples consisting of alcoholic extracts of C. sativa. The sensor was used for two main objectives: the quantification of major cannabinoids and the rapid identification of illegal samples. This required the analysis of numerous C. sativa samples from both fiber-type and recreational varieties, employing both univariate and multivariate approaches for data processing. A method for the quantification of Δ9-THCA, the main cannabinoid in recreational C. sativa varieties, was developed, and classification models capable of distinguishing legal from illegal samples based on Δ9-THC content were constructed. In both cases, the results obtained were satisfactory and consistent with chromatographic data.
Finally, a prototype of a portable device for in situ analysis of C. sativa extracts was developed in collaboration with an engineering research group. This device automates the preparation of the solution for the electrochemical analysis, starting from the plant sample, minimizing operator intervention. The system integrates micropumps, flow sensors, and an electrochemical cell housing the SPE-CB. Preliminary tests confirmed the device’s effectiveness, demonstrating that it enables rapid and comprehensive analysis of C. sativa plant samples
Epistula gratulatoria studentów polskich z 1637/38 roku do Francesca Monari, profesora praw obojga w Uniwersytecie Bolońskim
No full textA new caenogastropod genus from the upper Rhaetian of Lombardy: palaeobiogeographical history and implications for the Early Jurassic gastropod recovery
No full textA new gastropod genus and its type species, namely Ederazyga fanchini gen. et sp. nov., are described from the upper Rhaetian deposits of Lombardy (northern Italy) and tentatively placed into the family Zygopleuridae. The first appearance of Ederazyga is recorded in the lower Carnian deposits of Southern Alps and the stratigraphical distribution of the genus ends almost at the Triassic/Jurassic boundary. Its occurrence in Norian beds of the Nayband Basin (central Iran) suggests an eastward extension of the distribution during that time. Ederazyga is probably one of the Alpine gastropod taxa appearing in this area after the formation of the basin. The genus is possibly related to a group of Early Jurassic, medium to large Zygopleura-like species that are well represented in the Sinemurian and Pliensbachian carbonate platform deposits of the Mediterranean region and in the Hettangian to Pliensbachian successions of the European epicontinental shelf. This group shows an apparent species radiation in these areas testifying to the gastropod recovery following the Late Triassic decline in biodiversity. Ederazyga fanchini is shown to be congeneric with Cerithium? lateplicatum Klipstein, 1843, which is the type species of Camponaxis Bandel, 1995. The definition and diagnosis of Camponaxis was based on specimens that are clearly different, at generic and higher taxonomic levels, from the holotype of C.? lateplicatum. They belong to a distinct species here named Camponaxis bandeli sp. nov. Several species have been subsequently ascribed to Camponaxis following its original diagnosis. Therefore, we invoke ICZN Art. 70.3.2 in order to preserve the unambiguous identity of the genus and to ensure its nomenclatural stability. Camponaxis bandeli is fixed as the new type species for Camponaxis and C.? lateplicatum is here assigned to Ederazyga
Endosperm rice fiber by-product as source of bioactive phenolic compounds
No full textThis study investigated the valorization of rice industrial starch production fiber
by-products, as source of valuable antioxidant phenolic compounds. Six enzymes and acid or
alkaline solvents were tested. Total phenols yield and antioxidant activity were measured for
best treatment selection. Specific phenols were identified by HPLC-DAD. Overall, 2% v/w Celluclast
was identified as the best performing enzyme, leading to 436 μg gallic acid eq/gFW phenol
yield and increasing the recovery of ferulic and p-coumaric acids with respect to control and
other enzymatic treatments. Among chemical treatments, NaOH was more efficient than HCl
and H2SO4 and was more specific for ferulic acid release. All digestates showed antioxidant capacity,
up to 243 and 502 μg ascorbic acid eq/gFW for 2% v/w Celluclast and 1 M NaOH respectively.
Both enzymatic and chemical treatments were successfully applied and, depending
on extraction conditions, the release of specific phenolic compounds to obtain enriched digestates
was achieved
Design and construction of a movable in-vessel power electrode on RFX
No full textA movable in-vessel electrode has been designed for the RFX experiment in order to modify the radial electric field. The results of the tests performed on prototypes of the components are reported. The reliability of the structure has been assessed by a finite element structural analysis of the system. The power supply to be used for the electrode operation is describe
Palaeobiogeographical significance of some Pliensbachian gastropods from north-eastern Sicily (Italy)
No full textStarting from the study of two Pliensbachian gastropod species, the palaeobiogeographical significance of the gastropod faunas of north-eastern Sicily was investigated. The species [Muricotrochus (Laeviconulus) epuloides (Szabó, 1981) and Anoptychia crenata (Stoliczka, 1861)] stem from pelagic sediments cropping out on the eastern side of Monte Ziretto, near Taormina. Their palaeogeographical distribution is limited to the western Tethyan areas that were characterized by pelagic sedimentation since the Late Sinemurian or Early Pliensbachian. In order to ascertain how this information reflects features of the whole palaeogeographical domain, the Pliensbachian gastropod fauna from Rocche Rosse (Galati Mamertino, W of Messina, Sicily), published by M. Gemmellaro in 1911, was preliminarily studied. This is the most diversified and richest Early Jurassic gastropod fauna known from the Peloritani Mountains. From the palaeogeographical point of view, three stocks characterize the fauna. The most important consists of species occurring exclusively in areas characterized by pelagic sedimentation. The other two stocks, which are composed, respectively, by ubiquitous species and species known exclusively from Rocche Rosse, are not useful for paleobiogeographical comparisons. Then, the distribution of the two species analysed, which is restricted to the western Tethyan areas characterized by pelagic sedimentation, is in accordance with the results of the study of a diversified fauna and seems to reflect a peculiar feature of the Pliensbachian gastropod faunas of Peloritani Mountains
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