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31.
Fear of falling (FOF) is widely found in the elderly population and, regardless of its complex nature as a multicomponent construct, its related psychological variables have been overlooked as primary research topics. This article aims to examine the relationship between FOF, falls self efficacy, anxiety, balance, and perceived control over falling in a sample of older adults. A total of 100 subjects aged 60+ were asked about the presence of FOF, falls history, health, and functional status; they also completed the Falls Efficacy Scale (FES), the Geriatric Anxiety Inventory (GAI), the Perceived Control Over Falling Scale (PCOF), and the Performance-Oriented Assessment of Mobility and Balance (POMA-I). FOF was found to be associated with low falls self efficacy, low perceived control over falling, and reduced balance but not with anxiety. Conversely, a statistically significant association was found between GAI and FES, PCOF and POMA-I, and 47.1% of FOF was explained by two items from FES and GAI. FOF is influenced by variables that, though being commonly considered equivalent to FOF, do not fully explain it. A critical thought on the instruments used to evaluate FOF, is needed as well as additional studies to clarify the role of specific psychological variables.  相似文献   
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Objective:

This paper examines the development and evaluation of an automatic summarization system in the domain of molecular genetics. The system is a potential component of an advanced biomedical information management application called Semantic MEDLINE and could assist librarians in developing secondary databases of genetic information extracted from the primary literature.

Methods:

An existing summarization system was modified for identifying biomedical text relevant to the genetic etiology of disease. The summarization system was evaluated on the task of identifying data describing genes associated with bladder cancer in MEDLINE citations. A gold standard was produced using records from Genetics Home Reference and Online Mendelian Inheritance in Man. Genes in text found by the system were compared to the gold standard. Recall, precision, and F-measure were calculated.

Results:

The system achieved recall of 46%, and precision of 88% (F-measure = 0.61) by taking Gene References into Function (GeneRIFs) into account.

Conclusion:

The new summarization schema for genetic etiology has potential as a component in Semantic MEDLINE to support the work of data curators.

Highlights

  • Semantic MEDLINE streamlines information retrieval by succinctly expressing the meaning of sometimes complicated text and summarizing output according to a user''s needs.
  • Semantic MEDLINE identifies genes noted in biomedical text as associated with a disease process.
  • Semantic MEDLINE can potentially simplify secondary database curation.

Implications

  • Library information retrieval services can potentially benefit from automated applications such as Semantic MEDLINE.
  • Use of such automated applications can facilitate the library''s work in interdepartmental collaborative endeavors, thus reinforcing the library''s core value in its parent institution.
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The aim of the present study was to investigate the acute effect of the aerobic exercise volume on maximum strength and strength-endurance performance; and possible causes of strength decrements (i.e. central and peripheral fatigue). Twenty-one moderately trained men were submitted to a maximal incremental test to determine anaerobic threshold (AnT) and maximum dynamic strength (1RM) and strength-endurance (i.e. total volume load [TV]) tests to determine their baseline strength performance. Following, subjects performed six experimental sessions: aerobic exercise sessions (continuous running at 90% AnT) with different volumes (3?km, 5?km or 7?km) followed by 1RM or strength-endurance test in the 45° leg press exercise. Maximum voluntary isometric contraction (MVIC), voluntary activation (VA) level, contractile properties, and electromyographic activity (root mean square [RMS]) of the knee extensor muscles were assessed before and after aerobic exercises and after strength tests. TV was lower after 5?km and 7?km runs than in the control condition (12% and 22%, respectively). Additionally, TV was lower after 7?km than 3?km (14%) and 5?km (12%) runs. MVIC, VA, RMS, and contractile properties were reduced after all aerobic exercise volumes (~8%, ~5%, ~11% and ~6–14%, respectively). Additionally, MVIC, VA, and contractile properties were lower after strength tests (~15%, ~6%, ~9–26%, respectively). In conclusion, strength-endurance performance is impaired when performed after aerobic exercise and the magnitude of this interference is dependent on the aerobic exercise volume; and peripheral and central fatigue indices could not explain the different TV observed.  相似文献   
36.
This study analysed the behaviour of the geometric curvature of the spine during sirshasana. The position of dorsal retroreflective markers was computed via stereophotogrammetric analysis in six males and five females (29.4 ± 8.8 years, 63.0 ± 11.4 kg, 1.66 ± 0.08 m [average ± standard deviation]). The spinal points were projected onto the sagittal and frontal planes of the trunk, a polynomial was fitted to the data and the two-dimensional geometric curvature was quantified. The inferior lumbar lordosis decreased compared to the orthostatic position and gait, which may favour the posterior protrusion of the lumbar spinal nucleus pulposus in people with posterior herniation. The lateral deviation at the middle of the thoracic spine increases during sirshasana, which may reflect increased difficulties for postural control and spinal loads. It could be useful for promoting positive spinal structural and functional chronic adaptations for healthy participants, if the yoga programme is carefully planned and the spinal alignment is carefully monitored during a headstand. However, it may aggravate some spinal diseases, especially scoliosis.  相似文献   
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The aim of this study was to estimate the contribution of experience, body size and maturity status to variation in sport-specific skills of adolescent soccer players. The participants were 69 players aged 13.2-15.1 years from three clubs that competed in the highest division for their age group. Height and body mass were measured and stage of pubic hair development was assessed at clinical examination. Years of experience in football was obtained at interview. Six football skill tests were administered: ball control with the body, ball control with the head, dribbling with a pass, dribbling speed, shooting accuracy and passing accuracy. Multiple linear regression analysis was used to estimate the relative contributions of age, stage of sexual maturity, height, body mass and years of formal training in soccer to the six skill tests. Age, experience, body size and stage of puberty contributed significantly but in different combinations to the variance in four of the six skill tests: dribbling with a pass (21%; age, stage of maturity), ball control with the head (14%; stage of maturity, height, body height x body mass interaction), ball control with the body (13%; stage of maturity, years of training) and shooting accuracy (8%; stage of maturity, height; borderline significance, P = 0.06). There were no significant predictors for the tests of dribbling speed and passing accuracy. In conclusion, age, experience, body size and stage of puberty contributed relatively little to variation in performance in four of the six soccer-specific skill tests in adolescent footballers aged 13-15 years.  相似文献   
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This article analyses the editorial line of the BBC Portuguese Service during World War II, presenting evidence of how the output of the broadcasts was influenced by the need of the Foreign Office to maintain a good relationship with the authoritarian regime led by Oliveira Salazar. Focusing on the internal guidelines that ruled the Service, this history demonstrates how Portuguese language broadcasts never threatened the survival of the regime that ruled in Portugal, despite the fact that towards the end of the war the station was used as a weapon to pressure Salazar to give in to British demands, namely to end exports of tungsten to Germany. A discussion is presented on the difficult task the Portuguese Service had to accomplish throughout the war: to praise a dictatorship while promoting British views on the war.  相似文献   
40.
Knowledge Management Research & Practice - Information and knowledge have been cited over the last two decades as competitive advantage tools. Recently, the use of them has been discussed to...  相似文献   
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