1,720,982 research outputs found
Intermediate filament proteins immunologically related to cytokeratins in the oocyte of the fish Cyprinus carpio
No full textWe have used monoclonal antibodies specific for different sets of human cytokeratins and the anti-IFA (Intermediate Filament Antigen) antibody to investigate the expression of intermediate filament proteins in the mature oocyte of the teleost Cyprinus carpio. Several polypeptides have been identified, showing molecular weights ranging from 43 to 65 kDa. Two-dimensional analysis of the immunoreactive species revealed the presence of at least six major protein spots and a series of minor components, grouped in quite a narrow pi range from 5.52 to 6.28. The general complexity of the carp oocyte cytokeratin-related cytoskeleton appears to be higher than those described for oocytes of other vertebrate species
Time-of-day and circadian typology on memory retrieval
No full textThe cognitive functioning varies during the day and it can be modulated by the time in which individuals reach their arousal peak during the day. Morning-types should have cognitive peak in the morning while evening-types should have cognitive peak in the evening, reflecting the synchrony effect. The aim was to investigate time-of-day and synchrony effects on long-term memory with a network-like structure, using semantic classification and number-matching tasks. Evening- and morning-types performed two tasks in three times of the day: morning, afternoon and evening. In semantic classification task, a time-of-day effect was found while synchrony effect did not. Moreover, the circadian typology seemed to modulate the retrieval efficiency from long-term memory. In numbermatching task, no time-of-day as well as synchrony effects were reliable. As before, the circadian typology seemed to influence the retrieval of semantic information. The study may demonstrate that circadian typology seems to differ for the strategies in retrieval information from memory with a network-like structure
L’effetto di contiguità spaziale in un compito di memoria di lavoro: quali benefici per l’integrazione multimodale?
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Gestire diversi tipi di interferenza in memoria di lavoro: Uno studio con anziani
No full textL’obiettivo principale di questo studio è stato quello di indagare la capacità di gestire diversi tipi di interferenza in una versione visuo-spaziale del compito di Nelson et al. (2003) per indagare se i meccanismi coinvolti nella gestione dell’interferenza siano specifici per dominio o più generali in un gruppo di giovani e anziani
Drosophila melanogaster kl-3 and kl-5 Y-loops harbor triple-stranded nucleic acids
No full textPrimary spermatocyte nuclei of Drosophila melanogaster contain three prominent lampbrush-like loops. The development of these structures has been associated with the transcription of three fertility factors located on the Y chromosome, named kl-5, kl-3 and ks-1. These loci have huge physical dimensions and contain extremely long introns. In addition, kl-3 and kl-5 were shown to encode two putative dynein subunits required for the correct assembly of the sperm axoneme. Here, we show that both the kl-5 and kl-3 loops are intensely decorated by monoclonal antibodies recognizing triple-stranded nucleic acids, and that each loop presents a peculiar molecular organization of triplex structures. Moreover, immunostaining of Drosophila hydei primary spermatocytes revealed that also in this species - which diverged from D. melanogaster 58 million years ago - Y-loops are decorated by anti-triplex antibodies, strongly suggesting a conserved role of loop-associated triplexes. Finally, we showed that in D. melanogaster wild-type lines that are raised at the non-permissive temperature of 31±0.5°C (which is known to induce male sterility in flies) both the triplex immunostaining and the axonemal dynein heavy chains encoded by kl-3 and kl-5 are no longer detectable, which suggests a functional correlation between loop-associated triplexes, the presence of axonemal proteins and male fertility in fly.es, the presence of
axonemal proteins and male fertility in fly
Invecchiamento ed Effetti di Inter-Dipendent Self-Knowledge sull’integrazione di caratteristiche in Memoria di Lavoro
No full textHOW ECO-ENTREPRENEURS ARE TRANSFORMING ITALIAN TOURISM SECTOR: EVIDENCE FROM THE HOSPITALITY INDUSTRY.
No full textPurpose. This study investigates eco-entrepreneurship within Italy's hospitality sector, examining the motivations, practices, impacts, and challenges eco-entrepreneurs experience. It aims to enrich the discourse on sustainable tourism and ecological entrepreneurship in Italy. Design/methodology/approach. The research employs a multiple-case study methodology to focus on six small-scale enterprises in the Italian hospitality industry. Data collection comprised semi-structured interviews with key informants, supplemented by secondary data analysis. The interviews were coded and analysed using NVivo 14 to extract meaningful insights. Findings. The research reveals that personal commitment, environmental responsibility, and local heritage preservation are key drivers for eco-entrepreneurs. Key sustainable practices include resource conservation, waste management, and promoting local products. Transitioning to sustainable operations has been found to enhance reputation and customer trust, although the economic benefits of these initiatives remain unclear. The primary challenges identified are high investment costs, complex regulatory landscapes, and the need for targeted marketing to sensitise consumers towards sustainable options. Practical and Social Implications. The findings highlight potential policy interventions to simplify the certification process and provide economic incentives for eco-friendly practices. Eco-entrepreneurs effectively demonstrate how sustainability in hospitality can engage local communities and influence consumer behaviour towards eco-conscious travel, thereby driving broader societal shifts towards sustainability. Originality of the study. This research contributes to the limited empirical literature on eco-entrepreneurship within Italy's largely small-scale hospitality sector. It underscores the sector's potential to serve as a model for sustainable tourism practices, offering insights that could be applied to other regions and industries
Accessory tubules and axonemal microtubules of Apis mellifera sperm flagellum differ in their tubulin isoform content
No full textIn the insect sperm flagellum, an extra set of nine additional microtubules, named accessory tubules, is present surrounding the axoneme. Using a sarcosyl/urea extraction, we were able to fractionate the microtubular cytoskeleton of the sperm flagellum of the insect Apis mellifera resulting in the dissociation of the axonemal microtubule protein components and the accessory tubules. This has allowed us to compare the tubulin isoform content of axonemal microtubules and accessory tubules by immunoelectron microscopy and immunoblotting using a panel of monoclonal antibodies directed against different tubulin post-translational modifications (PTMs). All the PTMs occurring in axonemal tubulin are also present in accessory tubules, which indicates the close relativeness of accessory tubules to axonemal rather than to cytoplasmic microtubules. However, our results demonstrate the presence of significant differences in the tubulin isoform content of axonemal microtubules and accessory tubules. First, the tubulin tyrosination extent of accessory tubules is far lower than that of axonemal microtubules, thus confirming at the molecular level their morphogenetic origin as outgrowths from the B-subtubule of each microtubular doublet. Second, although polyglycylation seems to occurr at the same extent in both microtubular systems, α-tubulin exhibits a larger amount of monoglycylated sites in axonemal microtubules than in accessory tubules. Third, a greater amount of β-tubulin molecules is glutamylated in axonemal microtubules than in accessory tubules. Moreover, highly acidic isoforms, likely molecules with longer polyglutamate side chains, are present only in axonemal microtubules. Taken together, our data are indicative of a higher level of tubulin heterogeneity in axonemal microtubules than in accessory tubules. They also show a segregation of post-translationally modified isoforms between accessory tubules and axonemal microtubules and suggest the implication of PTMs in the functional specialization of the two microtubular systems. (C) 2000 Wiley-Liss, Inc
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