169 research outputs found
Operation of the photovoltaic system in Prague and data evaluation
Received: January 6th, 2021 ; Accepted: April 7th 2021 ; Published: April 12th 2021 ; Correspondence: [email protected] on-grid photovoltaic system was installed at the Faculty of Engineering in 2015.
The monitoring system developed in our laboratory monitors data and can also detect failure and
type of failure. The evaluation of the data shows that the amount of electricity produced slightly
exceeds the expected values predicted by the internationally used internet application PVGIS.
The effect of the aging of PV panels has so far had a minimal effect on the electricity produced.
Immediate output power is affected by multiple parameters. Higher temperatures reduce the
efficiency of energy conversion, so in summer the instantaneous power may be lower even at
higher radiation intensity and smaller angle of incidence
Design and data comparison of the photovoltaic power plants in the southern and northern hemispheres
We have recently developed a unique monitoring system for photovoltaic power plants
and have gradually improved it in recent years. The system is installed at about 80 power plants
in several European countries and at one power plant in Chile. We collect and evaluate all data
in our laboratory. In this paper we describe the unique design of a photovoltaic power plant in the
southern hemisphere in Chile with photovoltaic panels installed on tracking stands. We present
the evaluated data and we discuss their comparison with photovoltaic power plants installed in
Europe. We also discuss different solar conditions of these locations
Into the Origin of Electrical Conductivity for the Metal-Semiconductor Junction at the Atomic Level
The metal-semiconductor (M-S) junction based devices are commonly used in all
sorts of electronic devices. Their electrical properties are defined by the
metallic phase properties with a respect to the semiconductor used. Here we
make an in-depth survey on the origin of the M-S junction at the atomic scale
by studying the properties of the AuIn2 nanoelectrodes formed on the InP(001)
surface by the in situ electrical measurements in combination with a detailed
investigation of atomically resolved structure supported by the first-principle
calculations of its local electrical properties. We have found that a different
crystallographic orientation of the same metallic phase with a respect to the
semiconductor structure influences strongly the M-S junction rectifying
properties by subtle change of the metal Fermi level and influencing the band
edge moving at the interface. This ultimately changes conductivity regime
between Ohmic and Schottky type. The effect of crystallographic orientation has
to be taken into account in the engineering of the M-S junction-based
electronic devices
Patient perspectives of managing fatigue in ankylosing spondylitis, and views on potential interventions: a qualitative study
<p>Background: Fatigue is a major component of living with ankylosing spondylitis (AS), though it has been largely over-looked, and currently there are no specific agreed management strategies.</p>
<p>Methods: This qualitative exploratory study involved participants who are members of an existing population-based ankylosing spondylitis (PAS) cohort. Participants residing in South West Wales were invited to participate in a focus group to discuss; (1) effects of fatigue, (2) self-management strategies and (3) potential future interventions. The focus groups were audio-recorded and the transcripts were analysed using thematic analysis.</p>
<p>Results: Participants consisted of 3 males/4 females (group 1) and 4 males/3 females (group 2), aged between 35 and 73 years (mean age 53 years). Three main themes were identified: (1) The effects of fatigue were multi-dimensional with participants expressing feelings of being ‘drained’ (physical), ‘upset’ (emotional) and experiencing ‘low-mood’ (psychological); (2) The most commonly reported self-management strategy for fatigue was a balanced combination of activity (exercise) and rest. Medication was reluctantly taken due to side-effects and worries over dependency; (3) Participants expressed a preference for psychological therapies rather than pharmacological for managing fatigue. Information on Mindfulness-Based Stress Reduction (MBSR) was received with interest, with recommendations for delivery in a group format with the option of distance-based delivery for people who were not able to attend a group course.</p>
<p>Conclusions: Patients frequently try and manage their fatigue without any formal guidance or support. Our research indicates there is a need for future research to focus on psychological interventions to address the multi-faceted aspects of fatigue in AS.</p>
Clinical Characteristics Associated with Bacterial Bloodstream Coinfection in COVID-19
INTRODUCTION: Inappropriate antibiotic use in COVID-19 is often due to treatment of presumed bacterial coinfection. Predictive factors to distinguish COVID-19 from COVID-19 with bacterial coinfection or bloodstream infection are limited.
METHODS: We conducted a retrospective cohort study of 595 COVID-19 patients admitted between March 8, 2020, and April 4, 2020, to describe factors associated with a bacterial bloodstream coinfection (BSI). The primary outcome was any characteristic associated with BSI in COVID-19, with secondary outcomes including 30-day mortality and days of antibiotic therapy (DOT) by antibiotic consumption (DOT/1000 patient-days). Variables of interest were compared between true BSI (n = 25) and all other COVID-19 cases (n = 570). A secondary comparison was performed between positive blood cultures with true BSI (n = 25) and contaminants (n = 33) on antibiotic use.
RESULTS: Fever (\u3e 38 °C) (as a COVID-19 symptom) was not different between true BSI (n = 25) and all other COVID-19 patients (n = 570) (p = 0.93), although it was different as a reason for emergency department (ED) admission (p = 0.01). Neurological symptoms (ED reason or COVID-19 symptom) were significantly higher in the true BSI group (p \u3c 0.01, p \u3c 0.01) and were independently associated with true BSI (ED reason: OR = 3.27, p \u3c 0.01; COVID-19 symptom: OR = 2.69, p = 0.03) on multivariate logistic regression. High (15-19.9 × 10(9)/L) white blood cell (WBC) count at admission was also higher in the true BSI group (p \u3c 0.01) and was independently associated with true BSI (OR = 2.56, p = 0.06) though was not statistically significant. Thirty-day mortality was higher among true BSI (p \u3c 0.01). Antibiotic consumption (DOT/1000 patient-days) between true BSI and contaminants was not different (p = 0.34). True bloodstream coinfection was 4.2% (25/595) over the 28-day period.
CONCLUSION: True BSI in COVID-19 was associated with neurological symptoms and nonsignificant higher WBC, and led to overall higher 30-day mortality and worse patient outcomes
Psychosocial issues in engaging older people with physical activity interventions for the prevention of falls
This article presents an overview of the psychosocial factors that influence older peoples participation in physical activity interventions to prevent falls. The importance of psychosocial factors is stressed inasmuch as interventions will be rendered useless if they do not successfully gain the active participation of older people. The theory of planned behavior is used as a framework for the review on how knowledge (a prerequisite), attitudes, subjective norms (the social context), and perceived behavioral control (confidence) promote or inhibit the intention to carry out activities to prevent falls. The review is supplemented with evidence for self-identity to influence intention, and the article concludes with a discussion of the recommendations made by the Prevention of Falls Network Europe for engaging older people in falls prevention. Copyright © 2011 Canadian Association on Gerontology
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Does intensive management improve remission rates in patients with intermediate rheumatoid arthritis? (the TITRATE trial): study protocol for a randomised controlled trial.
BACKGROUND: Uncontrolled active rheumatoid arthritis can lead to increasing disability and reduced quality of life over time. 'Treating to target' has been shown to be effective in active established disease and also in early disease. However, there is a lack of nationally agreed treatment protocols for patients with established rheumatoid arthritis who have intermediate disease activity. This trial is designed to investigate whether intensive management of disease leads to a greater number of remissions at 12 months. Levels of disability and quality of life, and acceptability and cost-effectiveness of the intervention will also be examined. METHODS: The trial is a 12-month, pragmatic, randomised, open-label, two-arm, parallel-group, multicentre trial undertaken at specialist rheumatology centres across England. Three hundred and ninety-eight patients with established rheumatoid arthritis will be recruited. They will currently have intermediate disease activity (disease activity score for 28 joints assessed using an erythrocyte sedimentation rate of 3.2 to 5.1 with at least three active joints) and will be taking at least one disease-modifying anti-rheumatic drug. Participants will be randomly selected to receive intensive management or standard care. Intensive management will involve monthly clinical reviews with a specialist health practitioner, where drug treatment will be optimised and an individualised treatment support programme delivered based on several principles of motivational interviewing to address identified problem areas, such as pain, fatigue and adherence. Standard care will follow standard local pathways and will be in line with current English guidelines from the National Institute for Health and Clinical Excellence. Patients will be assessed initially and at 6 and 12 months through self-completed questionnaires and clinical evaluation. DISCUSSION: The trial will establish whether the known benefits of intensive treatment strategies in active rheumatoid arthritis are also seen in patients with established rheumatoid arthritis who have moderately active disease. It will evaluate both the clinical and cost-effectiveness of intensive treatment. TRIAL REGISTRATION: Current Controlled Trials, ID: ISRCTN70160382 . Registered on 16 January 2014.MRC Funding: MC_UP_1302/3
NIHR Funding: RP-PG-0610-1006
Reliability and sensitivity to change of the bristol rheumatoid arthritis fatigue scales
Objective. To examine the reliability (stability) and sensitivity of the Bristol Rheumatoid Arthritis Fatigue scales (BRAFs) and patient-reported outcome measures (PROMs) developed to capture the fatigue experience. The Multi-Dimensional Questionnaire (BRAF-MDQ) has a global score and four subscales (Physical Fatigue, Living with Fatigue, Cognitive Fatigue and Emotional Fatigue), while three numerical rating scales (BRAF-NRS) measure fatigue Severity, Effect and Coping. Methods. RA patients completed the BRAFs plus comparator PROMs. Reliability (study 1): 50 patients completed questionnaires twice. A same-day test-retest interval (minimum 60 min) ensured both time points related to the same 7 days, minimizing the capture of fatigue fluctuations. Reliability (study 2): 50 patients completed the same procedure with a re-worded BRAF-NRS Coping. Sensitivity to change (study 3): 42 patients being given clinically a single high dose of i.m. glucocorticoids completed questionnaires at weeks 0 and 2.Results. The BRAF-MDQ, its subscales and the BRAF-NRS showed very strong reliability (r = 0.82-0.95). BRAF-NRS Coping had lower moderate reliability in both wording formats (r = 0.62, 0.60). The BRAF-MDQ, its subscales and the BRAF-NRS Severity and Effect were sensitive to change, with effect sizes (ESs) of 0.33-0.56. As hypothesized, the BRF-NRS Coping was not responsive to the pharmaceutical intervention (ES 0.05). Preliminary exploration suggests a minimum clinically important difference of 17.5% for improvement and 6.1% for fatigue worsening. Conclusion. The BRAF scales show good reliability and sensitivity to change. The lack of BRAF-NRS Coping responsiveness to medication supports the theory that coping with fatigue is a concept distinct from severity and effect that is worth measuring separately. © The Author 2013. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved
Jumping into the deep-end: results from a pilot impact evaluation of a community-based aquatic exercise program
This multi-center quasi-experimental pilot study aimed to evaluate changes in pain, joint stiffness, physical function, and quality of life over 12 weeks in adults with musculoskeletal conditions attending ‘Waves’ aquatic exercise classes. A total of 109 adults (mean age, 65.2 years; range, 24–93 years) with musculoskeletal conditions were recruited across 18 Australian community aquatic centers. The intervention is a peer-led, 45 min, weekly aquatic exercise class including aerobic, strength, flexibility, and balance exercises (n = 67). The study also included a control group of people not participating in Waves or other formal exercise (n = 42). Outcomes were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and EuroQoL five dimensions survey (EQ-5D) at baseline and 12 weeks. Satisfaction with Waves classes was also measured at 12 weeks. Eighty two participants (43 Waves and 39 control) completed the study protocol and were included in the analysis. High levels of satisfaction with classes were reported by Waves participants. Over 90 % of participants reported Waves classes were enjoyable and would recommend classes to others. Waves participants demonstrated improvements in WOMAC and EQ-5D scores however between-group differences did not reach statistical significance. Peer-led aquatic exercise classes appear to improve pain, joint stiffness, physical function and quality of life for people with musculoskeletal conditions. The diverse study sample is likely to have limited the power to detect significant changes in outcomes. Larger studies with an adequate follow-up period are needed to confirm effects
Mall Walking Program Environments, Features, and Participants: A Scoping Review
Introduction
Walking is a preferred and recommended physical activity for middle-aged and older adults, but many barriers exist, including concerns about safety (ie, personal security), falling, and inclement weather. Mall walking programs may overcome these barriers. The purpose of this study was to summarize the evidence on the health-related value of mall walking and mall walking programs.
Methods
We conducted a scoping review of the literature to determine the features, environments, and benefits of mall walking programs using the RE-AIM framework (reach, effectiveness, adoption, implementation, and maintenance). The inclusion criteria were articles that involved adults aged 45 years or older who walked in indoor or outdoor shopping malls. Exclusion criteria were articles that used malls as laboratory settings or focused on the mechanics of walking. We included published research studies, dissertations, theses, conference abstracts, syntheses, non research articles, theoretical papers, editorials, reports, policy briefs, standards and guidelines, and non research conference abstracts and proposals. Websites and articles written in a language other than English were excluded.
Results
We located 254 articles on mall walking; 32 articles met our inclusion criteria. We found that malls provided safe, accessible, and affordable exercise environments for middle-aged and older adults. Programmatic features such as program leaders, blood pressure checks, and warm-up exercises facilitated participation. Individual benefits of mall walking programs included improvements in physical, social, and emotional well-being. Limited transportation to the mall was a barrier to participation.
Conclusion
We found the potential for mall walking programs to be implemented in various communities as a health promotion measure. However, the research on mall walking programs is limited and has weak study designs. More rigorous research is needed to define best practices for mall walking programs’ reach, effectiveness, adoption, implementation, and maintenance.Ye
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