1,720,978 research outputs found
Sequele psicologiche della morte endouterina. Una rassegna panoramica della letteratura
No full textLa morte endouterina e il suo impatto sui genitori e sugli operatori sanitari sono stati studiati ampiamente in ambiente nordico e anglosassone, ma non ci è noto nessuno studio italiano su di essi. Per la rilevanza delle sequele psicologiche che tale perdita comporta abbiamo voluto affrontare questo tema in vista di un possibile intervento preventivo nella realtà italiana.
Gli aspetti psichici che accompagnano l'intera gravidanza sono caratterizzati tanto da componenti gratificatorie che da componenti d'angoscia. In questi due aspetti si ritrovano sia gli elementi legati alla vita che quelli evocanti la morte; infatti, proprio nel momento in cui il vivere trova la sua spinta iniziale, vi è il timore che il processo non vada a compimento. Pertanto tutta la gravidanza è permeata da queste due forze, con andamenti ciclici
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
Influence of temperature and hydraulic retention on the production of volatile fatty acids during anaerobic fermentation of cow manure and maize silage
Full text linkThe aim of this study was to verify the efficiency of a separate hydrolysis step by testing different working temperatures (37-55°C) and hydraulic retention times (two, four and six days) and by evaluating readily biodegradable carbon production. The fermentation products included primarily acetic, propionic and butyric acids. These acids can be easily converted into biogas or can be recovered in a biorefinery approach, for example, to produce polyhydroxyalkanoates. The optimal condition was found by applying an organic loading rate of 17.9 gTVS m-3 with a four-day retention time at 37°C for an acidification yield of 183.2 gCODVFA kgVSfed-1
Anaerobic membrane reactor: Biomethane from chicken manure and high-quality effluent
Full text linkChicken manure was treated in a pilot scale reactor anaerobic membrane bioreactor constituted by a completely mixed reactor combined with an ultrafiltration tube-shaped membrane in a side-stream configuration. The process operated under mesophilic condition and the inhibition of high concentration of ammonia was avoided using an ammonia stripping system. The experimental plan included a preliminary evaluation, where organic loading rates between 1.0 and 7.6 kgVS/m3/day were tested. The organic load higher than 4 kgVS/m3/d caused the accumulation of volatile fatty acids and process instability. Application of the ammonia stripping was also evaluated. The best performances were achieved using a retention time of 21 days, an organic load between 1.4 and 2.0 kgVS/m3/d, and the recirculation of stripped permeate. Reduction of the ammonia permeate content by 90% through stripping and utilization of a mixture of chicken manure/water/permeate in a ratio of 0.22/0.72/0.72 w/w led to a specific biogas production of 0.59 m3biogas/kgVS and methane content of 66–69%. The ammonia thus removed can be recovered by sulphuric acid treatment as ammonium sulphate, which can be used as a fertilizer. The proposed configuration allowed satisfactory biogas production with appropriate methane percentages, recovery of ammonium sulphate, and a high-quality effluent
Two phase anaerobic codigestion of organic waste and activated sludge: energy and rbCOD recovery.
No full textThe following study dealt with the application of the anaerobic co-digestion process for production of biohythane and volatile fatty acids (VFA)
Long-term validation of polyhydroxyalkanoates production potential from the sidestream of municipal wastewater treatment plant at pilot scale
No full textIn this study, polyhydroxyalkanoates (PHAs) production integrated with the via-nitrite nitrogen removal from anaerobic reject water was investigated at pilot scale under long-term period. The pilot plant was located in Carbonera wastewater treatment plant (WWTP) (Treviso, Italy) and comprised the following units: i) rotating belt dynamic filter (RBDF) for the recovery of cellulosic primary sludge (CPS); ii) fermentation unit for the production of volatile fatty acids (VFAs); iii) ultrafiltration unit (UF) for solid/liquid separation of the fermented sludge; iv) nitritation sequencing batch reactor (N-SBR) for the oxidation of ammonia to nitrite; v) selection SBR (S-SBR) where aerobic-feast and anoxic-famine conditions were established to select PHA-accumulating biomass and vi) an accumulation SBR (A-SBR) were intracellular PHA content was maximized through the feed-on-demand strategy. Results showed that around 80% of the influent ammonia was efficiently removed by the system when both N-SBR and S-SBR operated with volumetric nitrogen loading rate (vNLR) of 1.64–1.72 kgN/m3 d and 0.60–0.63 kgN/m3 d, respectively. Accumulation tests showed PHA yields ranging between 0.58 and 0.61 g CODPHA/g CODVFA, indicating an effective selection strategy. The overall mass balance assessment demonstrated that around 0.32 g of COD per gram of COD treated can be recovered as bio-based products. The integration of nitrogen removal and PHA production in the sidestream resulted in a methane recovery up to 4.0 m3CH4/PE y and a maximal PHA production of 1.2 kgPHA/PE y with a potential revenue for the WWTP up to 6.5 €/PE y
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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