1,721,014 research outputs found
Measures of dynamic balance during level walking in healthy adult subjects: Relationship with age, anthropometry and spatio-temporal gait parameters
No full textThe maintenance of balance in dynamic conditions (e.g. during walking) is a necessary requirement that motor control must reach to avoid falls. However, this is a challenging situation, since to ensure the forward progression of the body, the center of mass must stay outside the base of support in the sagittal plane, and simultaneously remain inside the lateral borders in the frontal plane. Deviation from normative data of healthy subjects in dynamic balance could be used to quantify gait stability, fall risk and to provide hints for rehabilitation. However, normative data can be influenced by age, sex, anthropometry and spatio-temporal gait parameters, and such differences among subjects and leg side can hamper accurate assessment. The aims of this study were to investigate, in a group of healthy subjects: (1) possible asymmetry in dynamic balance maintenance strategies between leg sides, (2) the influence of age, sex and anthropometry on stability and (3) its dependence by spatio-temporal gait parameters. A total of 34 healthy subjects aged between 21 and 71 years, and ranging from 50.1 to 101.6 kg of body mass and from 155.0 to 188.9 cm of height were assessed on spatio-temporal and dynamic balance parameters (Foot Placement Estimator at heel strike and Margin of Stability at mid-stance) during self-selected gait. No parameter showed differences between legs. Dynamic balance parameters were influenced by sex, age, body mass and height mainly in the frontal plane. These measures were also correlated with gait speed and stride length both in the antero-posterior and medio-lateral directions. In addition also cadence and step width influenced the stability in the sagittal and frontal planes, respectively. The findings of this study confirm the symmetry in motor control of dynamic balance during self-selected gait in healthy subjects. Sex, anthropometry and spatio-temporal gait parameters have a significant effect on stability parameters, and this should be taken into account in dynamic balance studies
Is lower peripheral information weighted differently as a function of step number during step climbing?
No full textThe importance of peripheral visual information during stair climbing and how peripheral visual information is weighted as a function of step number during step climbing is unclear. Previous authors postulated that the knowledge of predictable characteristics of the steps may decrease reliance on foveal vision and transfer the online visual guidance of stair climbing to peripheral vision. Hence the aim of this study was to investigate if and how the occlusion of the lower peripheral visual field influenced stair climbing and if peripheral visual information was weighted differently between steps. Ten young adult male participants ascended a 5-step staircase under 2 visual conditions: full vision (FV) and lower visual occlusion (LO). Kinematic data (100 Hz) were collected. The effect of Vision and Step condition on vertical forefoot clearance was examined with a Repeated Measures 2-way ANOVA. Tukey's HSD test was used for post-hoc comparisons. A significant interaction Vision x Step and main effect of Step were found (p <= 0.04): vertical forefoot clearance was greater in LO compared to FV condition only on the 1st and the 2nd steps (p < 0.013) and on the last step compared to the other steps (p < 0.01). These findings suggest that online peripheral visual information is more relevant when negotiating the first two steps, rather than the end of a staircase and that the steps subsequent the first few ones may require different information likely based on proprioception or working memory of the step height
Lo studio dei processi lessicali e sublessicali mediante l’esame dei parametri temporali di scrittura in bambini di scuola primaria
No full textRiassunto. Lo studio esamina i processi di elaborazione lessicale e sublessicale in un
gruppo di bambini normolettori mediante la rilevazione di parametri temporali nella
scrittura sotto dettato. Hanno partecipato allo studio 15 bambini di terza classe e 19
bambini di quinta classe di scuola primaria. Le variabili temporali esaminate sono sensibili
alle differenti caratteristiche psicolinguistiche degli stimoli. Nella scrittura di parole
ambigue, che richiedono l’accesso a una rappresentazione ortografica, e di parole
regolari richiedenti l’applicazione di regole sensibili al contesto, si riscontrano tempi di
scrittura più lunghi e un maggior numero di pause rispetto alla scrittura di parole e
pseudoparole a trascrizione regolare. I risultati evidenziano l’utilità dell’esame delle variabili
temporali nel rilevare l’efficienza dei processi di scrittura lessicale e sublessicale
in soggetti con sviluppo tipico di diversa scolarizzazione
β-Mannosidase from Cellulomonas fimi: Immobilization Study and Application in the β-Mannoside Synthesis
No full textThe β-D-mannopyranoside linkage is found in a number of biological structures, in particular, in the core trisaccharide of N-linked glycoproteins, as well as within the antigenic polysaccharides of Salmonella, yeasts, and glycolipids. The construction of this glycosydic bond by chemical approach is very challenging and requires cumbersome protection and activation steps prior to glycosylation. In this context, β-mannosidase from Cellulomonas fimi (Cf-β-Man) was immobilized for the first time, and it was employed in the synthesis of β-mannosides. Cf-β-Man immobilized on IDA-Co2+-agarose allows the synthesis of the disaccharide, cyanomethyl β-D-mannopyranosyl-(1→6)-2-acetamido-2deoxy-1-thio-β-D-glucopyranoside, with a higher conversion compared to the soluble enzyme (20% vs. 5%) after 6 h under best conditions. This explorative work opens new scenarios concerning the design of engineered Cf-β-Man mutants and their immobilization in order to obtain a robust and recyclable biocatalyst for applications in chemoenzymatic glycan synthesis
Group art treatment and cognitive decline: a pilot study with fMRI
Get PDFBackground:
Group therapy interventions represent an effective and concrete rehabilitation alternative for people with Alzheimer’s disease (PWA); interestingly, a recent review show that art therapy is useful approach in dementia (Chancellor et al., 2014) improving cognitive and behavioral functions and well-being of PWA.
Aims:
To investigate the effects of a rehabilitative approach based on group visual art treatment on memory, language, visuo-constructional and executive abilities, art reasoning and well-being in PWA. Possible changes in neural functions at rest were also investigated.
Methods:
18 persons (Mean age=76.6, SD=5.22) with Mild Cognitive Impairment (MCI; n=11) or mild-AD (n=7) underwent a twice weekly group treatment using visual art and drawing for 7 weeks. Neuropsychological, functional and behavioral evaluations were performed blindly by a neuropsychologist at baseline and at the end of treatment. Motor indexes of Rey-Osterrieth Complex Figure Test were collected with a technological device. Participants underwent a fMRI before and after the treatment. Results were obtained comparing participants’ performances at the first evaluation session vs. the latest. The PWA group was also observed by two independent judges trained in the use of the Italian adaptation of the Greater Cincinnati Chapter Well-Being Observational Tool (Sauer et al., 2014).
Results:
General cognition (MMSE, p <.01) and language comprehension (Token, p <.01) were positively affected by the intervention. Improvements in the recall and execution of the Rey figure were found in AD>MCI (Fig. 1). Changes in the neural functions at rest were also found. Significant correlation (p <.001) between judges scores of Greater Cincinnati Chapter Well-Being Observational Tool was observed and a good level of tool reliability was confirmed. In the AD group, a higher social interest (p =.052) together with a lower disengagement (p < .05) we observed. Although no significant, engagement and pleasure presented a positive trend while sadness and negative affect a negative one.
Conclusions:
These preliminary data bring further evidence of the importance of group treatments based on the visual arts in optimizing the management of individuals with AD on different domains
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
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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
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