1,721,079 research outputs found
Multivariate modeling for environmental spatio-temporal data
No full textAn environmental data set often concerns different correlated variables measured at some locations of the
study area and for several time points. In this case, the data set presents a multivariate spatio-temporal
structure; therefore appropriate modeling techniques which take into account the spatio-temporal
relationships among the variables are needed. The space-time LCM (ST-LCM) based on admissible spatiotemporal models may successfully capture the spatio-temporal behaviour of the phenomena under study and can be used for prediction purposes.
After a brief presentation of the spatio-temporal multivariate geostatistical framework, a case study is
proposed and the following aspects are considered:
1. estimating the spatio-temporal interrelationships among the variables of interest and, consequently,
identifying the basic hidden components in space and in time which characterize the same variables; the
simultaneous diagonalization-based method is applied to several matrix variograms in order to detect the
basic independent components which contribute to define the multivariate correlation structure of the
observed variables (De Iaco et al., 2013);
2. modeling the spatio-temporal correlation among the variables under study by using the ST-LCM (De
Iaco et al., 2005); in this step, the basic models at the selected scales of spatio-temporal variability have
been properly chosen after the inspection of the non separability index computed for the basic components
(De Iaco and Posa, 2013);
3. spatio-temporal cokriging performed by a modified version of GSLib routine to obtain prediction,
over the study area, for the variable of interest.
Note that the ST-LCM used in this paper is based on mixture models, i.e. the ST-LCM has been fitted by
selecting different classes of spatio-temporal correlation measures, related to different scales of spatiotemporal variability
Compulsive usage of Internet and mobile phone by teenagers: a new empirical evidence
No full textIn the recent years, the rapid increase in mobile phone and Internet usage,
has determined various benefits to their users, such as social relations and new ways
of communication (virtual interactions by email, chat or instant messaging). On the
other hand, an abuse of these technologies might cause adverse health effects (i.e.
social isolation and other forms of psychological disorders), especially on young
people, which is considered to be at high risk for pathological and addictive technologies
use.
In this paper, a case study on Internet and mobile phone habits among adolescents,
is discussed. In particular, a questionnaire has been submitted to a sample of students,
with ages ranging from 11 to 13 years old, attending some schools belonging
to the districts of Lecce and Brindisi (Apulia Region). A cluster analysis combined
with a binary logistic regression has been applied, in order to: a) outline the profile
of teenagers that overuse Internet and mobile phone, b) assess the relationships
among behaviours and attitudes of teenagers, with reference to the above-mentioned
technologies
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
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
[The treatment of the cardiac patient in dentistry and oromaxillofacial surgery. I. The practical management of patients with arrhythmias]. Il trattamento del paziente cardiopatico in odontoiatria ed in chirurgia oro-maxillo-facciale. Nota 1: Management pratico nei pazienti portatori di turbe del ritmo.
No full textCardiac patients consist of a high incidence rate in odontostomatology, both clinical and surgical. Moreover this serious complication disease conditions odontostomatological and, particularly, surgical works. In this article the authors present the results of several years of research carried out to obtain a correct clinical and therapeutic approach for clinical and surgical dentistry. After an introduction on the clinical features of heart diseases the most important clinical cases of heart dysrhythmia are discussed: like, i.e. hypokinetic arrhythmia, hyperkinetic arrhythmia and the management of patients with pacemakers. The principal diacritic features of dysrhythmic diseases are illustrated. Anxiety is a sort of disease not directly related with dysrhythmia. Moreover a lot of clinical studies find in heart arrhythmia the principal problem caused by anxiety on heart physiology. Consequently the authors describe anxiety in the same part of pathologies commonly known as heart dysrhythmia. In the last phase the authors illustrate the most opportune therapeutic steps corresponding to the principal pathologies described above. These matters were dealt with from an odontostomatological point of view. The results obtained suggest the necessity of keeping to the management that was described. Actually a low percentage of accidents occurred only when the above-mentioned clinical processes were completely performed.
PMID: 922131
A synbiotic mixture improves flatulence in irritable bowel syndrome
No full textP.1.254
A SYNBIOTIC MIXTURE IMPROVES FLATULENCE IN
IRRITABLE BOWEL SYNDROME
C. Cappello ∗ , F. Tremolaterra, D. Consalvo, C. Ciacci, P. Iovino
Policlinico Universitario Federico II, Napoli, Italy
Background and aim: Recent data suggest that the intestinal microbiota
might play a role in the pathogenesis of irritable bowel syndrome (IBS) A
recent metanalysis showed that probiotics reduce symptoms of IBS in adults,
according to individual strains.The aim of this study was to test the efficacy of
a commercially available synbiotic mixture which contains a concentrations
of a range of bacteria (5×109 Lactobacillus plantarum, 2×109 L. casei and L.
gasseri, 1×109 Bifidobacterium infantis and B. longum, 1×109 L.sporogenes,
1×109, L. acidophilus and L. salivarus, 5×109 Streptococcus termophilus,
and as well as inuline (beneo synergy) as a prebiotic in patients with Rome III
IBS.
Material and methods: A double-blind, randomized placebo-control clinical
trial of the synbiotic mixture (5g BID) vs. placebo over 4-weeks after a 2
weeks run-in period. Primary endpoints: global satisfactory relief of abdominal
flatulence and bloating; Patients who reported at least 50% of the weeks
of treatment with satisfactory relief were designated as responders. Secondary
endpoints: Change in GI symptoms (abdominal pain, flatulence, bloating and
urgency) on 100 mm of VAS scales, in stool frequency and bowel functions on
validated adjectival scales and in quality of life (SF36). Pre- and post-treatment
total and segmental colonic transit time was assessed according to Metcalf et
Al. A strict exclusion of concomitant medications that could interfere with the
study was requested.
Results: 64 IBS patients (synbiotic n=32, 64% females, mean age 38.7±12.6
years) completed the treatment period. Proportions of responders for satisfactory
relief of flatulence and bloating were not significantly different between
synbiotic and placebo group. Treatment with the synbiotic was associated with
reduced flatulence (ANCOVA, p<0.05). Quality of life significantly improved
in all scale but the vitality in the synbiotic group, while in the placebo group
the significance was reached only in role physical, bodily pain and mental
health. No other significantly differences were disclosed in any endpoints, in
total and segmental colonic transit measurements between groups.
Conclusions: This synbiotic mixture improves flatulence score in patients
with IBS. This data are in keeping with a role of intestinal bacteria in the
pathophysiology of IBS
- …
