305,372 research outputs found
Proposal of New Natural Hydraulic Lime-Based Mortars for the Conservation of Historical Buildings
No full textNHL mortars are known to be compatible materials for the conservation of architectural heritage. To improve their properties with regard to salt resistance and lower their carbon footprint, NHL-based mortars with salt inhibitor agents were studied and different formulations were produced: NHL-based mortars (MSs), composed of natural hydraulic lime; and sand and cocciopesto mortars (MSCs), in which NHL, sand and brick powder were admixed with two different products, diethylenetriaminapenta and chitosan, in different concentrations. The mortar performance was tested against freeze–thaw and salt crystallization through immersion–drying cycles in a 14% sodium sulfate solution. The results highlighted that the addition of cocciopesto was effective in increasing the salt resistance, but increased the water intake during the freeze–thaw tests. The use of DTPMP produced less thixotropic mortars and decreased the water uptake, but worsened the salt resistance of hardened mortars. Chitosan allowed a good workability of fresh mortar; its water uptake was similar to the reference mortar and slightly increased the salt resistance. In the cocciopesto samples, both additives reduced the weight variation during freeze–thaw tests; meanwhile, for the lime samples, the additives increased the weight variation during the final cycles
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Betão auto-compactável com incorporação de resíduo de mármore
No full text[PT] O setor da construção civil é responsável por um grande consumo de matérias-primas e pela
intensa geração de resíduos, e vem trabalhando na criação de procedimentos e produtos,
buscando cada vez mais a sustentabilidade. O betão auto-compactável (BAC) permite a
produção de um material mais “verde”, por exemplo, através do reaproveitamento de
resíduos industriais. No presente trabalho desenvolveu-se um programa experimental
visando a otimização de composições de BAC com incorporação do resíduo do
beneficiamento de mármores, da região do Alentejo em Portugal, conhecida como Zona do
Mármore. O programa experimental foi realizado segundo um plano fatorial ao nível do
betão, fixando a composição da pasta, para otimizar o esqueleto sólido formado pelos
agregados. Os resultados obtidos permitiram concluir que é possível substituir cimento por
pó de mármore sem afetar significativamente as propriedades de autocompactabilidade e
assim conseguir composições de BAC de mais baixa resistência e mais eco-eficientes,
adequadas a uma grande variedade de aplicações de betão estrutural.Este trabalho foi financiado pelo Projeto POCI-01-0145-FEDER-007457 – CONSTRUCT – Instituto de I&D em Estruturas e Construções – financiado pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) e por fundos nacionais através da Fundação para a Ciência e a Tecnologia I.P. Os autores agradecem ainda o apoio do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Instituto Federal Fluminense (IFF) e do Centro Tecnológico da Pedra Natural de Portugal (CEVALOR).Destefani, A.; Nunes, S.; Sousa-Countinho, J. (2017). Betão auto-compactável com incorporação de resíduo de mármore. En HAC 2018. V Congreso Iberoamericano de hormigón autocompactable y hormigones especiales. Editorial Universitat Politècnica de València. 137-146. https://doi.org/10.4995/HAC2018.2018.5484OCS13714
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Elevated serum progesterone on the day of HCG administration in IVF is associated with a higher pregnancy rate in polycystic ovary syndrome
No full textOur study compared 84 patients with polycystic ovary syndrome (PCOS) with 84 control patients who had normal ovaries and who were matched for the main determinants of success in in-vitro fertilization (IVF) and embryo transfer. Serum concentrations of oestradiol and progesterone on the day of human chorionic gonadotrophin (HCG) injection were significantly higher in PCOS than in normal patients (oestradiol 2016 +/- 1.8 pg/ml versus 1456 +/- 40.9 pg/ml, P or = 1.2 ng/ml showed a higher pregnancy and miscarriage rate than PCOS patients with progesterone < 1.2 ng/ml (26.6 versus 17.9%, P < 0.01; and 41.7% versus 14.3%, P < 0.01 respectively). These findings suggest that premature progesterone production does not have an adverse effect on pregnancy rate in PCOS, but on the contrary, may be a predictor for success in IVF/embryo transfer
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
No full textThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
«Se questo è un uomo» e «I sommersi e i salvati»: significati e significanti
No full textSi esaminano le opere di Primo Levi attraverso una lente linguistica e strutturale. Il contributo indaga come la scelta dei termini (significanti) costruisca il profondo contenuto etico e storico (significati) della testimonianza, distinguendo tra la narrazione immediata e la riflessione saggistic
May car washing represent a risk for Legionella infection?
No full textBackground. Legionella is a ubiquitous Gram-negative bacterium naturally found in aquatic environments. It can pose a health problem when it grows and spreads in man-made water systems. Legionella pneumophila is the most common cause of Legionnaires’ disease nowadays, a community-acquired pneumonia with pulmonary symptoms and chest radiography no different from any other form of infectious pneumonia. Legionella monitoring is important for public health reasons, including the identification of unusual environmental sources of Legionella.
Methods. We report two cases of Legionnaires’ disease associated with two different car wash installations in the province of Vicenza, in the Veneto region, northeastern Italy. Patients were not employees of the car wash installations, but users of the service. In both cases, Legionella antigen was detected in urine using the Alere BinaxNOW® Legionella Urinary Antigen, and Legionella antibodies were detected in serum using SERION ELISA classic Legionella pneumophila 1-7 IgG and IgM. Water samples were also analyzed as part of the surveillance program for Legionella prevention and control in compliance with the Italian guidelines.
Results. Both patients had clinical symptoms and chest radiography compatible with pneumonia, and only one of them had diabetes as a risk factor. Legionella urinary antigen and serological test on serum samples were positive for Legionella in both patients, even if much slighter in the case A due to the retrospective serological investigation performed a year later the episode and after the second clinical case occurred in the same district. The environmental investigations highlighted two different car wash plants as potential source of infection. A certified company using shock hyperchlorination was asked to disinfect the two plants and, subsequently, control samples resulted negative for Legionella pneumophila.
Conclusions. Any water source producing aerosols should be considered at risk for the transmission of Legionella bacteria, including car wash installations frequently used by a large number of customers and where poor maintenance probably creates favorable conditions for Legionella overgrowth and spreading. Additional research is needed to ascertain optimal strategies for Legionella monitoring and control, but environmental surveillance, paying careful attention to possible unconventional sources, should remain an important component of any Legionnaires’ disease prevention program. Additionally, all available diagnostic methods would be recommended for the confirmation of all cases even in the event of non-serogroup 1 Legionella pneumophila infection, probably underestimated at this time
[Report to Chief J. E. Curry, by an unknown author #2]
No full textReport to Chief J. E. Curry, by an unknown author. The report contains a list of officers who gave depositions to the United States Attorney
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