scholarly journals Disparity of time-contrast curves generated by various types of power injectors used in magnetic resonance imaging

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Marcus Doppler ◽  
Ewald Moser ◽  
Uros Klickovic ◽  
Christian Nasel

Abstract The profiles of time-contrast (TC) -curves from popular MRI injectors derived at the injection site of the attached tube-line system were compared. Variations of TC-profiles were previously reported to potentially influence image quality in time critical MRI measurements. TC-curves from five injectors obtained during commonly used injection protocols were assessed according to representative quality criteria: (1) correlation strength between a fitted boxcar function and the TC-curve (cBCF) and (2) difference between true and expected injection time (dBIT). Additionally, the impact from technical injector properties: pump type, line volume, maximum injection power and type of contrast medium (CM) on the TC-profiles was evaluated. Injectors using a piston-syrinx (PS) mechanism for CM-injection performed significantly better than those working with a peristaltic roller pump (RP) technique. Besides injection mechanism, line filling volume showed a strong influence on the final TC-curves, where larger filling volumes induced worse cBCF- and dBIT-results. Therefore, to achieve an optimal bolus in clinical MRI use of a PS-injector seems recommendable. Besides their pump mechanism, RP-injectors appeared additionally hampered by their high volume line systems, pointing out an unfavourable coinicidence of these technical features in RP-injectors. This should be considered, particularly, in comparative or time-critical MRI-studies.

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
S Pallikadavath ◽  
R Patel ◽  
CL Kemp ◽  
M Hafejee ◽  
N Peckham ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Cardiovascular adaptations as a result of exercise conducted at high-intensity and high-volume are often termed the ‘Athlete’s heart’. Studies have shown that these cardiovascular adaptations vary between sexes. It is important that both sexes are well represented in this literature. However, many studies assessing the impact of high-dose exercise on cardiovascular outcomes under-recruit female participants. Purpose This scoping review aimed to evaluate the representation of females in studies assessing the impact of high-dose exercise on cardiovascular outcomes and demonstrate how this has changed over time. Methods The scoping review protocol as outlined by Arksey and O’Malley was used. OVID and EMBASE databases were searched and studies independently reviewed by two reviewers. Studies must have investigated the effects of high-dose exercise on cardiovascular outcomes. To assess how the recruitment of females has changed over time, two methods were used. One, the median study date was used to categorise studies into two groups. Two, studies were divided into deciles to form ten equal groups over the study period. Mean percentage of female recruitment and percentage of studies that failed to include females were calculated. Results Overall, 250 studies were included. Over half the studies (50.8%, n = 127) did not include female participants. Only 3.2% (n = 8) did not include male participants. Overall, mean percentage recruitment was 18.2%. The mean percentage of recruitment was 14.5% before 2011 and 21.8% after 2011. The most recent decile of studies demonstrated the highest mean percentage of female recruitment (29.3%) and lowest number of studies that did not include female participants (26.9%). Conclusion Female participants are significantly underrepresented in studies assessing cardiovascular outcomes caused by high-dose exercise. The most recent studies show that female recruitment may be improving, however, this still falls significantly short for equal representation. Risk factors, progression and management of cardiovascular diseases vary between sexes, hence, translating findings from male dominated data is not appropriate. Future investigators should aim to establish barriers and strategies to optimise fair recruitment. Mean percentage females recruited per study (%) Percentage studies that do not include women (%) Overall (n = 250) 18.2 50.8 (n = 127) Studies before 2011 (n = 121) 14.5 59.5 (n = 72) Studies after 2011 (n = 129) 21.8 42.6 (n = 55) Table 1: Female recruitment characteristics. The year 2011 (median study year) was chosen as this divides all included studies into two equal groups.


Drones ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 42
Author(s):  
Fahad E. Salamh ◽  
Umit Karabiyik ◽  
Marcus K. Rogers ◽  
Eric T. Matson

The raising accessibility of Unmanned Aerial Vehicles (UAVs), colloquially known as drones, is rapidly increasing. Recent studies have discussed challenges that may come in tow with the growing use of this technology. These studies note that in-depth examination is required, especially when addressing challenges that carry a high volume of software data between sensors, actuators, and control commands. This work underlines static and live digital evidence traceability challenges to further enhance the UAV incident response plan. To study the live UAV forensic traceability issues, we apply the `purple-teaming’ exercise on small UAVs while conducting UAV forensic examination to determine technical challenges related to data integrity and repeatability. In addition, this research highlights current static technical challenges that could pose more challenges in justifying the discovered digital evidence. Additionally, this study discusses potential drone anti-forensic techniques and their association with the type of use, environment, attack vector, and level of expertise. To this end, we propose the UAV Kill Chain and categorize the impact and complexity of all highlighted challenges based on the conducted examination and the presented scientific contribution in this work. To the best of our knowledge, there has not been any contribution that incorporates `Purple-Teaming’ tactics to evaluate UAV-related research in cybersecurity and digital forensics. This work also proposes a categorization model that classifies the discovered UAV static and live digital evidence challenges based on their complexity and impact levels


Author(s):  
Giorgia Gon ◽  
Abdunoor M. Kabanywanyi ◽  
Petri Blinkhoff ◽  
Simon Cousens ◽  
Stephanie J. Dancer ◽  
...  

Abstract Background Healthcare associated infections (HAI) are estimated to affect up to 15% of hospital inpatients in low-income countries (LICs). A critical but often neglected aspect of HAI prevention is basic environmental hygiene, particularly surface cleaning and linen management. TEACH CLEAN is an educational intervention aimed at improving environmental hygiene. We evaluated the effectiveness of this intervention in a pilot study in three high-volume maternity and newborn units in Dar es Salaam, Tanzania. Methods This study design prospectively evaluated the intervention as a whole, and offered a before-and-after comparison of the impact of the main training. We measured changes in microbiological cleanliness [Aerobic Colony Counts (ACC) and presence of Staphylococcus aureus] using dipslides, and physical cleaning action using gel dots. These were analysed with descriptive statistics and logistic regression models. We used qualitative (focus group discussions, in-depth interviews, and semi-structured observation) and quantitative (observation checklist) tools to measure why and how the intervention worked. We describe these findings across the themes of adaptation, fidelity, dose, reach and context. Results Microbiological cleanliness improved during the study period (ACC pre-training: 19%; post-training: 41%). The odds of cleanliness increased on average by 1.33 weekly during the pre-training period (CI = 1.11–1.60), and by 1.08 (CI = 1.03–1.13) during the post-training period. Cleaning action improved only in the pre-training period. Detection of S. aureus on hospital surfaces did not change substantially. The intervention was well received and considered feasible in this context. The major pitfalls in the implementation were the limited number of training sessions at the hospital level and the lack of supportive supervision. A systems barrier to implementation was lack of regular cleaning supplies. Conclusions The evaluation suggests that improvements in microbiological cleanliness are possible using this intervention and can be sustained. Improved microbiological cleanliness is a key step on the pathway to infection prevention in hospitals. Future research should assess whether this bundle is cost-effective in reducing bacterial and viral transmission and infection using a rigorous study design.


2021 ◽  
Vol 38 (2) ◽  
pp. 158-165
Author(s):  
Ilaria Pergolini ◽  
I. Ekin Demir ◽  
Christian Stöss ◽  
Klaus Emmanuel ◽  
Robert Rosenberg ◽  
...  

Background: This survey aimed to register changes determined by the COVID-19 pandemic on pancreatic surgery in a specific geographic area (Germany, Austria, and Switzerland) to evaluate the impact of the pandemic and obtain interesting cues for the future. Methods: An online survey was designed using Google Forms focusing on the local impact of the pandemic on pancreatic surgery. The survey was conducted at 2 different time points, during and after the lockdown. Results: Twenty-five respondents (25/56) completed the survey. Many aspects of oncological care have been affected with restrictions and delays: staging, tumor board, treatment selection, postoperative course, adjuvant treatments, outpatient care, and follow-up. Overall, 60% of respondents have prioritized pancreatic cancer patients according to stage, age, and comorbidities, and 40% opted not to operate high-risk patients. However, for 96% of participants, the standards of care were guaranteed. Discussion/Conclusions: The first wave of the COVID-19 pandemic had an important impact on pancreatic cancer surgery in central Europe. Guidelines for prompt interventions and prevention of the spread of viral infections in the surgical environment are needed to avoid a deterioration of care in cancer patients in the event of a second wave or a new pandemic. High-volume centers for pancreatic surgery should be preferred and their activity maintained. Virtual conferences have proven to be efficient during this pandemic and should be implemented in the near future.


2020 ◽  
Vol 17 (12) ◽  
pp. 5605-5612
Author(s):  
A. Kaliappan ◽  
D. Chitra

In today’s world, an immense measure of information in the form of unstructured, semi-structured and unstructured is generated by different sources all over the world in a tremendous amount. Big data is the termed coined to address these enormous amounts of data. One of the major challenges in the health sector is handling a high-volume variety of data generated from diverse sources and utilizing it for the wellbeing of human. Big data analytics is one of technique designed to operate with monstrous measures of information. The impact of big data in healthcare field and utilization of Hadoop system tools for supervising the big data are deliberated in this paper. The big data analytics role and its theoretical and conceptual architecture include the gathering of diverse information’s such as electronic health records, genome database and clinical decisions support systems, text representation in health care industry is investigated in this paper.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Prabod Dharshana Munasinghe ◽  
D.G.K. Dissanayake ◽  
Angela Druckman

Purpose The process of fashion design varies between market segments, yet these variations have not yet been properly explored. This study aims to examine the fashion design process as practised at the mass-market level, as this is the most vibrant and the largest market segment in terms of production volumes and sales. Design/methodology/approach It is observed that 15 semi-structured interviews were conducted with mass-market fashion designers. Key activities of the mass-market design process were identified and a comparative analysis was conducted with the general design process. Findings The mass-market design process is found to prioritise profits rather than aesthetic aspects, with the buyer exercising more power than the designer. This hinders creativity, which, in turn, may impede a move towards more environmentally benign designs. Originality/value The clothing industry is responsible for high environmental impacts and many of these impacts arise through decisions made in the design stage. In particular, the mass-market for clothing because of its high volume of sales and fast throughput, accounts for a great deal of the impact. However, little is understood about the design process that is practised in the mass-fashion market. This paper fills the gap by developing a framework that describes the mass-market design process. Understanding the design process will enable progress to be made towards achieving the United Nations Sustainable Development Goal 12: Responsible Consumption and Production.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Dileep R Yavagal ◽  
Vasu Saini ◽  
Violiza Inoa ◽  
Hannah E Gardener ◽  
Sheila O Martins ◽  
...  

Introduction: The COVID-19 pandemic has strained the healthcare systems across the world but its impact on acute stroke care is just being elucidated. We hypothesized a major global impact of COVID-19 not only on stroke volumes but also on thrombectomy practice. Methods: A 19-item questionnaire survey aimed to identify the changes in stroke volumes and treatment practices seen during COVID-19 pandemic was designed using Qualtrics software. It was sent to stroke and neuro-interventional physicians around the world who are part of the executive committee of a global coalition, Mission Thrombectomy 2020 (MT2020) between April 5 th to May 15 th , 2020. Results: There were 113 responses across 25 countries. Globally there was a median 33% decrease in stroke admissions and a 25% decrease in mechanical thrombectomy (MT) procedures during COVID-19 pandemic compared to immediately preceding months (Figure 1A-B). This overall median decrease was despite a median increase in stroke volume in 4 European countries which diverted all stroke patients to only a few selected centers during the pandemic. The intubation policy during the pandemic for patients undergoing MT was highly variable across participating centers: 44% preferred intubating all patients, including 25% centers that changed their policy to preferred-intubation (PI) vs 27% centers that switched to preferred-conscious-sedation (PCS). There was no significant difference in rate of COVID-19 infection between PI vs PCS (p=0.6) or if intubation policy was changed in either direction (p=1). Low-volume (<10 stroke/month) compared with high-volume stroke centers (>20 strokes/month) are less likely to have neurointerventional suite specific written personal protective equipment protocols (74% vs 88%) and if present, these centers are more likely to report them to be inadequate (58% vs 92%). Conclusion: Our data provides a comprehensive snapshot of the impact on acute stroke care observed worldwide during the pandemic.


2021 ◽  
Vol 9 ◽  
Author(s):  
Jiaxiang Li ◽  
Biao Wang ◽  
Jian Sun ◽  
Shuhong Wang ◽  
Xiaohong Zhang ◽  
...  

Ice shedding causes transmission lines to vibrate violently, which induces a sharp increase in the longitudinal unbalanced tension of the lines, even resulting in the progressive collapse of transmission towers in serious cases, which is a common ice-based disaster for transmission tower-line systems. Based on the actual engineering characteristics of a 500 kV transmission line taken as the research object, a finite element model of a two-tower, three-line system is established by commercial ANSYS finite element software. In the modeling process, the uniform mode method is used to introduce the initial defects, and the collapse caused by ice shedding and its influencing parameters are systematically studied. The results show that the higher the ice-shedding height is, the greater the threat of ice shedding to the system; furthermore, the greater the span is, the shorter the insulator length and the greater the dynamic response of the line; the impact of ice shedding should be considered in the design of transmission towers.


Marine pollution is not a new issue in our country. This could be problem if pollution happened at Kilim Karst Geoforest which is one of the UNESCO Geopark. UNESCO Geopark aims to protect geosites and natural environment. Pollution could exist when it relates to the high volume of tourist that flock to the Kilim Karst Geoforest especially Sungai Kilim. Thus, the increase number of tourists can lead to higher amount of pollution due to water tourism activities. This study is to identify the water tourism activities at Geopark, Pulau Langkawi and to analyse the perception among tourists on the impact of water tourism activities towards marine pollutions. A set of questionnaires was developed, and it was distributed to a total number of 100 respondents that available at Kilim Karst Geopark, Pulau Langkawi. This research was analysed by using Statistical Package for Social Science (SPSS). The findings of the results show water tourisms activities contribute towards marine pollution by using correlation analysis. It more proven when natural environment, for example the mangroves being threatened by tourist boat activities and pollution due to littering.


2021 ◽  
Author(s):  
Lauren Sinnenberg ◽  
Craig A Umscheid ◽  
Frances S Shofer ◽  
Damien Leri ◽  
Zachary F Meisel

BACKGROUND The use of graphic narratives, defined as stories that use images for narration, is growing in health communication. OBJECTIVE The aim of this study was to describe the design and implementation of a graphic narrative screensaver (GNS) to communicate a guideline recommendation (ie, avoiding low-value acid suppressive therapy [AST] use in hospital inpatients) and examine the comparative effectiveness of the GNS versus a text-based screensaver (TBS) on clinical practice (ie, low-value AST prescriptions) and clinician recall. METHODS During a 2-year period, the GNS and the TBS were displayed on inpatient clinical workstations. The numbers of new AST prescriptions were examined in the four quarters before, the three quarters during, and the one quarter after screensavers were implemented. Additionally, an electronic survey was sent to resident physicians 1 year after the intervention to assess screensaver recall. RESULTS Designing an aesthetically engaging graphic that could be rapidly understood was critical in the development of the GNS. The odds of receiving an AST prescription on medicine and medicine subspecialty services after the screensavers were implemented were lower for all four quarters (ie, GNS and TBS broadcast together, only TBS broadcast, only GNS broadcast, and no AST screensavers broadcast) compared to the quarter prior to implementation (odds ratio [OR] 0.85, 95% CI 0.78-0.92; OR 0.89, 95% CI 0.82-0.97; OR 0.87, 95% CI 0.80-0.95; and OR 0.81, 95% CI 0.75-0.89, respectively; <i>P</i>&lt;.001 for all comparisons). There were no statistically significant decreases for other high-volume services, such as the surgical services. These declines appear to have begun prior to screensaver implementation. When surveyed about the screensaver content 1 year later, resident physicians recalled both the GNS and TBS (43/70, 61%, vs 54/70, 77%; <i>P</i>=.07) and those who recalled the screensaver were more likely to recall the main message of the GNS compared to the TBS (30/43, 70%, vs 1/54, 2%; <i>P</i>&lt;.001). CONCLUSIONS It is feasible to use a graphic narrative embedded in a broadcast screensaver to communicate a guideline recommendation, but further study is needed to determine the impact of graphic narratives on clinical practice.


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