91 research outputs found
Explaining Intranet use with the Technology Acceptance Model
This paper considers the application of the technology acceptance model (TAM) in explaining intranet usage in two organizations. The TAM was originally developed for explaining technology acceptance and has since been successfully applied to a number of technologies. Its suitability for modelling intranet use is considered here. The model is tested in two UK companies from the banking and engineering sectors. Study 1 finds that the TAM may be valuable as a tool for helping with analysing and understanding intranet usage. The second study indicates that its applicability may be variable between intranets and demonstrates that self-report and actual measures of usage are not interchangeable when applying such a model. The findings have implications for previous and current research employing the TAM and for intranet research in general
Galactic chemical abundance evolution in the solar neighborhood up to the Iron peak
We have developed a detailed standard chemical evolution model to study the
evolution of all the chemical elements up to the iron peak in the solar
vicinity. We consider that the Galaxy was formed through two episodes of
exponentially decreasing infall, out of extragalactic gas. In a first infall
episode, with a duration of 1 Gyr, the halo and the thick disk were
assembled out of primordial gas, while the thin disk formed in a second episode
of infall of slightly enriched extragalactic gas, with much longer timescale.
The model nicely reproduces the main observational constraints of the solar
neighborhood, and the calculated elemental abundances at the time of the solar
birth are in excellent agreement with the solar abundances. By the inclusion of
metallicity dependent yields for the whole range of stellar masses we follow
the evolution of 76 isotopes of all the chemical elements between hydrogen and
zinc. Those results are confronted with a large and recent body of
observational data, and we discuss in detail the implications for stellar
nucleosynthesis.Comment: 19 pages, 14 figures, submitted to A&
Chemical composition of red horizontal branch stars in the thick disk of the Galaxy
High-resolution spectra of 13 core helium-burning stars in the thick disk of
the Galaxy have been obtained with the SOFIN spectrograph on the Nordic Optical
Telescope to investigate abundances of up to 22 chemical elements. Abundances
of carbon were studied using the C_2 Swan (0,1) band head at 5635.5 A. The
wavelength interval 7980-8130 A with strong CN features was analysed in order
to determine nitrogen abundances and 12C/13C isotope ratios. The oxygen
abundances were determined from the O I line at 6300 A. Abundances in the
investigated stars suggest that carbon is depleted by about 0.3 dex, nitrogen
is enhanced by more than 0.4 dex and oxygen is unaltered. The 12C/13C ratios
are lowered and lie between values 3 and 7 which is in agreement with "cool
bottom processing" predictions (Boothroyd & Sackmann 1999). The C/N ratios in
the investigated stars are lowered to values between 0.7 and 1.2 which is less
than present day theoretical predictions and call for further studies of
stellar mixing processes. Abundance ratios of O, Mg, Eu and other heavy
chemical elements to iron in the investigated stars show a pattern
characteristic of thick disk stars. The results provide evidence that the thick
disk population has a distinct chemical history from the thin disk. The onset
of the bulk of SN Ia is suggested to appear around [Fe/H] = -0.6 dex.Comment: A&A LaTeX, 11 pages, 9 enclosed figures, Astronomy & Astrophysics, in
pres
Proteomic Analysis Reveals Age-related Changes in Tendon Matrix Composition, with Age- and Injury-specific Matrix Fragmentation
Energy storing tendons, such as the human Achilles and equine superficial digital flexor tendon (SDFT), are highly prone to injury, the incidence of which increases with aging. The cellular and molecular mechanisms that result in increased injury in aged tendons are not well established but are thought to result in altered matrix turnover. However, little attempt has been made to fully characterize the tendon proteome nor determine how the abundance of specific tendon proteins changes with aging and/or injury. The aim of this study was, therefore, to assess the protein profile of normal SDFTs from young and old horses using label-free relative quantification to identify differentially abundant proteins and peptide fragments between age groups. The protein profile of injured SDFTs from young and old horses was also assessed. The results demonstrate distinct proteomic profiles in young and old tendon, with alterations in the levels of proteins involved in matrix organization and regulation of cell tension. Furthermore, we identified several new peptide fragments (neopeptides) present in aged tendons, suggesting that there are age-specific cleavage patterns within the SDFT. Proteomic profile also differed between young and old injured tendon, with a greater number of neopeptides identified in young injured tendon. This study has increased the knowledge of molecular events associated with tendon aging and injury, suggesting that maintenance and repair of tendon tissue may be reduced in aged individuals and may help to explain why the risk of injury increases with aging
Validity of maximum isometric tongue pressure as a screening test for physical frailty: Cross-sectional study of Japanese community-dwelling older adults
Aim: Maximum isometric tongue pressure (MIP) seems to have a diagnostic value for oral phase dysphagia. The present study aimed to examine the association between MIP and frailty, and to assess the screening validity of MIP for physical frailty. Methods: We carried out a cross-sectional study, and enrolled participants aged ?60 years from Japanese national medical check-ups in 2015 and 2016. The Fried frailty phenotype model was used. We analyzed odds ratios (OR) and 95% confidence intervals (CI) of physical frailty using one standard deviation increments of tongue pressure. Receiver operating characteristic curves were obtained to predict physical frailty using MIP values. Results: Out of 1603 participants, 968 were categorized as non-frail, 605 as pre-frail and 30 as frail. In logistic regression analysis, one standard deviation increment of MIP significantly differentiated frail and pre-frail: the OR for frail with one standard deviation increment in MIP was 0.37 (95% CI 0.26?0.54, P < 0.001), and the OR for pre-frail was 0.63 (95% CI 0.57?0.70, P < 0.001). The area under the receiver operating characteristic curve for predicting frailty with MIP score was as high as 0.776 (95% CI 0.689?0.862). A point of MIP 35 kPa had a sensitivity of 90.0%, specificity of 40.4%, a positive likelihood ratio of 1.5 and a negative likelihood ratio of 0.2 for predicting frailty. Conclusions: MIP performance is independently associated with frailty. MIP also can be used as a simple screening tool for frailty
Best practice for motor imagery: a systematic literature review on motor imagery training elements in five different disciplines
<p>Abstract</p> <p>Background</p> <p>The literature suggests a beneficial effect of motor imagery (MI) if combined with physical practice, but detailed descriptions of MI training session (MITS) elements and temporal parameters are lacking. The aim of this review was to identify the characteristics of a successful MITS and compare these for different disciplines, MI session types, task focus, age, gender and MI modification during intervention.</p> <p>Methods</p> <p>An extended systematic literature search using 24 databases was performed for five disciplines: Education, Medicine, Music, Psychology and Sports. References that described an MI intervention that focused on motor skills, performance or strength improvement were included. Information describing 17 MITS elements was extracted based on the PETTLEP (physical, environment, timing, task, learning, emotion, perspective) approach. Seven elements describing the MITS temporal parameters were calculated: study duration, intervention duration, MITS duration, total MITS count, MITS per week, MI trials per MITS and total MI training time.</p> <p>Results</p> <p>Both independent reviewers found 96% congruity, which was tested on a random sample of 20% of all references. After selection, 133 studies reporting 141 MI interventions were included. The locations of the MITS and position of the participants during MI were task-specific. Participants received acoustic detailed MI instructions, which were mostly standardised and live. During MI practice, participants kept their eyes closed. MI training was performed from an internal perspective with a kinaesthetic mode. Changes in MI content, duration and dosage were reported in 31 MI interventions. Familiarisation sessions before the start of the MI intervention were mentioned in 17 reports. MI interventions focused with decreasing relevance on motor-, cognitive- and strength-focused tasks. Average study intervention lasted 34 days, with participants practicing MI on average three times per week for 17 minutes, with 34 MI trials. Average total MI time was 178 minutes including 13 MITS. Reporting rate varied between 25.5% and 95.5%.</p> <p>Conclusions</p> <p>MITS elements of successful interventions were individual, supervised and non-directed sessions, added after physical practice. Successful design characteristics were dominant in the Psychology literature, in interventions focusing on motor and strength-related tasks, in interventions with participants aged 20 to 29 years old, and in MI interventions including participants of both genders. Systematic searching of the MI literature was constrained by the lack of a defined MeSH term.</p
Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study
Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.
Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.
Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001).
Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication
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