1,720,965 research outputs found
MuSER (Multiple Sclerosis Expected Rate) Predictive Model Development
No full textMultiple Sclerosis (MS) is the most diffused among rare neurological pathologies, as it affects about 0.031% people all over the world. Its
prevalence in the United States (US) was calculated to be around 0.14%, but according to National Multiple Sclerosis Society (NMSS) MS is not
properly monitored and registered within American territory and the creation of a MS archive is expected to ameliorate the calculus accuracy. The
aim of this work is to develop a simple but reliable biostatistical predictive model called MuSER (Multiple Sclerosis Expected Rate); it was projected
based on the ascending trend that was observed during previous studies, although not dependable, is theoretically reliable, at least considering R2
coefficients. Efficiency of MuSER model will be assessed at the end of 2019.
In order to predict MS incidence within an ethnically homogeneous population. Although not absolutely dependable, is theoretically reliable, at
least considering R2 coefficients. Efficiency of MuSER model will be assessed at the end of 2019
Kinetic model of Chlorella vulgaris growth with and without extremely low frequency-electromagnetic fields (EM-ELF)
No full textChlorella vulgaris was grown in a two specially-designed bench-scale photobioreactors with and without the application of a low intensity, low frequency electromagnetic field (EM-ELF) of about 3 mT. Cell concentration and tendency of cells to form aggregates inside the reactor were recorded over a 30 days-time period at 0.5 L-constant medium volume in the temperature range 289-304 K. At 304 K, after a cultivation period of 15 days, the rate of cell death became predominant over that of growth. In the temperature range 289–299 K, a two step-kinetic model based on the mitotic division and the clusterization processes was developed and critically discussed. The best-fitted curves turned out to have a sigmoid shape, and the competition between mitosis and clusterization was investigated. Without EM-ELF, the temperature dependence of the specific rate constant of the mitotic step (k1) yielded to an apparent total enthalpy of 15+/-6 kJ mol-1, whose value was not influenced by the EM-ELF application. The electromagnetic field was shown to exert a significant effect on the exothermic clusterization step. The heat exchange due to binding between cells and liquid medium turned out to be –44+/-5 kJ mol-1 in the absence of EM-ELF and –68+/-8 kJ mol-1 when it was active. Microscopic optical Optical microscopy observations were in agreement with the model predictions and confirmed that EM-ELF is was able to enhance cell clusterization
Cultivation of Chlorella vulgaris in tubular photobioreactors: A lipid source for biodiesel production
No full textChlorella vulgaris was cultivated in two different 2.0 L-helicoidal and horizontal photobioreactors at 5 klux using the bicarbonate contained in the medium and ambient air as the main CO2 sources. The influence of bicarbonate concentration on biomass growth as well as lipid content and profile was first investigated in shake flasks, where the stationary phase was achieved in about one half the time required by the control. The best NaHCO3 concentration (0.2 g L-1) was then used in both photobioreactors. While the fed-batch run performed in the helicoidal photobioreactor provided the best result in terms of biomass productivity, which was (84.8 mg L-1 d-1) about 2.5-fold that of the batch run, the horizontal configuration ensured the highest lipid productivity (10.3 mg L-1 d-1) because of a higher lipid content of biomass (22.8 %). These preliminary results suggest that the photobioreactor configuration is a key factor either for the growth or the composition of this microalga. The lipid quality of C. vulgaris biomass grown in both photobioreactors is expected to meet the standards for biodiesel, especially in the case of the helicoidal configuration, provided that further efforts will be made to optimize the conditions for its production as a biodiesel source
Studio della crescita autotrofa di Chlorella vulgaris impiegando bicarbonato come fonte di carbonio
No full textL’obiettivo dello studio è stato l’impiego di bicarbonato di sodio come fonte alternativa di carbonio in colture di Chlorella vulgaris, usualmente realizzate con la sola CO2. La microalga è stata inoculata in beuta e fatta crescere per 15 giorni in colture batch in presenza di NaHCO3 (0.2, 0.4 e 0.8 g/L), mantenendola in sospensione mediante insufflazione d’aria. La miglior concentrazione di NaHCO3 (0.2 g/L) è stata in seguito impiegata in fotobioreattore elicoidale mediante alimentazione fed-batch di NaHCO3. Le analisi gas-cromatografiche effettuate sull’estratto lipidico della biomassa non hanno evidenziato sostanziali differenze tra le diverse prove effettuate in batch. In conclusione si può affermare che il bicarbonato di sodio, a basse concentrazioni, può essere efficacemente impiegato per le crescite di C. vulgaris, essendo in grado di ridurre il tempo necessario al raggiungimento dello stato pseudo-stazionario e di aumentarne la concentrazione cellulare e la resa lipidica
A critical review of biological processes and technologies for landfill leachate treatment
No full textThe most common method to deal with the huge production of municipal wastes is still the disposal in landfills which, however, generates a leachate with high contents of organic and nitrogen pollutants. Requirements must be fixed by law to control leachate release from such landfills, and effective treatment processes and technologies must be applied to reduce its impact on the environment. Biological processes for leachate treatment are discussed in this review, in the former part of which attention is paid to leachate formation and its qualitative and quantitative features, while the latter deals with the state-of-the-art of the most effective biotechnological treatments presently employed. Processes, alternative methods, and technological improvements are compared, with special focus on novel technologies to remove nitrogen pollutants from leachate, highlighting advantages and drawbacks of each treatment
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Development of milk fermented with Lactobacillus acidophilus fortified with Vitis vinifera marc flour
No full textSome by-products of wine industry still contain nutrients and functional compounds that make them potential ingredients to formulate new high value-added food products. The aim of this study is to develop milk fermented with Lactobacillus acidophilus fortified with marc flour of different cultivars of Vitis vinifera from wine production and to evaluate their influence on fermentation kinetics, probiotic counts, phenolic compounds, sugar content and antioxidant activity. The acidification time was significantly shortened by these enrichments (by up to 2.7h), and the bacterial count during cold storage resulted in stronger fortification of samples (up to 4.13 %) when compared to control tests. Fermented milk containing grape marc showed considerable amounts of phenolic compounds with notable antioxidant activity, as well as significant amounts of total sugars. The most important aspect of this paper is the feasibility of using winery by-products, rich in phenolic compounds, as natural supplements to fortify probiotic-fermented milk
Variations on the Author
Get PDF“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
Get PDFWe 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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