1,721,194 research outputs found

    Enhanced lignocellulosic component removal and biomethane potential from chestnut shell by a combined hydrothermal–alkaline pretreatment

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    This study proposes new perspectives for the management and biorefinery of wastes deriving from the agri–food sector such as chestnut shell (CS), which was here used as an organic feedstock for biomethane production through anaerobic digestion (AD). 1–5% alkaline (i.e. NaOH and KOH), hydrothermal (i.e. at 100 °C) and combined hydrothermal–alkaline pretreatments were employed to enhance the CS biodegradability prior to biochemical methane potential (BMP) tests conducted under mesophilic conditions. The hydrothermally–pretreated CS with 3% NaOH achieved the highest biomethane yield of 253 (±9) mL CH4·g VS−1 coupled to a volatile solid reduction of 48%. The hydrothermal–alkaline pretreatment positively affected both delignification and hemicellulose polymerization, promoting an approximately 2.4–fold higher substrate biodegradability compared to the untreated CS, which only reached a CH4 production of 104 (±5) mL CH4·g VS−1. AD proceeded via volatile fatty acid accumulation, subsequently followed by methane production that was effectively simulated via the modified Gompertz kinetic having a R2 of 0.974–0.999. Among the physical–chemical parameters characterizing the CS, the soluble chemical oxygen demand (sCOD) was highly correlated with the BMP showing a Pearson coefficient of 0.952. The cumulative biomethane yield, the sCOD and the cellulose, hemicellulose and lignin amount of CS were also processed through the least square method, obtaining a useful regression equation to predict the BMP. The economic assessment indicated that the hydrothermal–alkaline pretreatment is a cost–effective method to improve the BMP of CS, also for future full–scale applications

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Variations on the Author

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    “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

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    We 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

    Preliminary functional results after transanal irrigation in patients undergoing SHiP procedure for low rectal cancer

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    The short-stump and high-anastomosis pull-through procedure (SHiP) is a newly introduced technique in the treatment of rectal cancer. This procedure does not involve the creation of a diverting ostomy with great improvement of the patients’ quality of life in the post-operative period. However, functional post-operative alterations such as low anterior rectal resection syndrome (LARS) may occur. In this context, trans-anal irrigation (TAI) may represent a viable option in the treatment and management of LARS symptoms. The aim of the present study is to investigate the role of TAI in patients operated on SHiP procedure for low rectal cancer. A prospective database of 17 patients who underwent a SHiP procedure was maintained from April 2019 to December 2021. Anal continence and functional outcomes were assessed through LARS score and Cleveland Clinic Incontinence Score (CCIS), respectively. All patients with a LARS score > 21 underwent TAI in the post-operative period. LARS median value was 36 (IQR = 8) and drastically improved after TAI treatment to 3 (IQR = 3), as the CCIS at a mean follow-up of 9 months (SD ± 5.02). Good functional result was reached in 12 out of 13 patients (92%). Our study confirms that patients with severe post-operative dysfunction could benefit from the use of TAI
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