Accepted and presented at The Design of Medical Devices Conference (DMD2016)

The usability of medical devices has increasingly become a focus for many healthcare facilities seeking to reduce the likelihood of error or injury, improve communications of results, and achieve operational cost savings For a premium ultrasound system, navigation and image processing is based around a touch panel, trackball, and various knobs and buttons for individual features. A sonographer is required to use one hand to operate these controls. The sonographer's other hand controls a probe for scanning a patient's internal organs or blood flowing through blood vessels. Ultrasound systems are often used in environments in which other factors are competing for the end user's attention so they must be streamlined and easy to use. In order to gauge the usability of ultrasound systems, three comparable premium systems from different vendors were evaluated in a comparative usability test. The intent was to evaluate scanning workflows for efficiency, effectiveness, and satisfaction, as sonographers use the systems' control panels, touch panels, and monitors. Usability test results reveal assumptions that end users make and inform designers of medical device characteristics that may lead to higher risks of errors and deviations and ultimately, a product recall Methods In order to determine how a particular system performs in relation to similar competitor systems, a comparative usability test can be conducted. This test involves end users of the systems and requires them to complete the same set of tasks using each of the systems. In this study, sonographers with a specialty in abdominal sonography served as usability test participants. They evaluated the three ultrasound systems through simulated but representative scanning tasks. These tasks were based on the standard abdominal exam tasks. A few examples of the types of tasks included taking measurements of organs on 2D images and annotating images with text, arrows, and body markers. The specialty of abdominal sonography was chosen in order to successfully recruit a large group of candidates for participation with similar demographics and experience. This usability test involved 20 participants: it included 10 practicing sonographers who currently use one vendor's ultrasound system (system A) and 10 who currently use another vendor's ultrasound system (system B). Each group evaluated a third system, a new beta ultrasound system, and the system they are not familiar with (i.e., current system A users evaluated the new beta system and system B). The usability test was conducted at a user research facility equipped with a state-of-the-art usability testing lab. The facility had no design or development ties to any of the three ultrasound systems evaluated in this usability study. Human models were involved in the study to act as patients during the usability tests. These patients provided sonographers with real physiology to scan. Both adult males and females, who were generally healthy, fairly easy-to-scan, and with no suspected abnormal anatomy, were recruited as models. At the beginning of a usability session, the participant received training on the beta system and one of the other systems. For each system, a training video was created by Macadamian that featured a sonographer who had experience on that particular system, completing similar tasks with similar features. After watching each video, participants were given the same amount of time to familiarize themselves with each system before the usability tests began. A counterbalancing technique, random order with rotation, was used for the training and usability tests. This technique helps to mitigate carryover effects from participant-to-participant. Carryover effects include fatigue, practice, habituation, sensitization, and adaptation. At the end of every usability test, each participant was asked to complete the system usability scale (SUS) questionnaire and indicate his/her preferred system. Results from the SUS questionnaire provide a clear, definite score (out of 100) regarding perceptions of usability To provide objective research results, three specific measures were taken. User experience (UX) professionals who had no ties to the design or development of any of the systems ran the study. An experienced UX Researcher acted as the test facilitator, so as not to guide or provide advice to the test participants. These measures were coupled by the use of identical test protocols for each system. Matched-pair t-tests were used to determine if any significant differences existed between the designs based on usability metrics captured during the tests. Usability metrics captured by UX researchers included: task completion rates, number of errors, number of deviations, and ease-of-use ratings as well as qualitative feedback from participants. The matched pairs consisted of the data from the beta system and the corresponding data from either system A or system B for the same participant. Results The number of observed errors and task completion rates measured for effective design. Design elements were further understood with the collection of qualitative feedback. A higher rate of successful task completion was observed during the beta system's usability tests (twice as many test tasks were completed with 100% success rate, as compared to the other vendors' results). This was largely due to a more intuitive touch panel design and layout. For example, when annotating an image with text, users were provided with color-coded groupings of annotations that were found to be more straightforward than on the other systems. Participants also stated that annotation and measurement tasks were easier to complete because of the clear labeling of the trackball legend and touch screen controls when performing such actions as adjusting, moving, and deleting items on an image. The design of a simple control panel with related functions grouped closely together enabled sonographers to search less and have more confidence in their actions with less hand gestures around the control panel. Context-aware knobs and buttons that lit up upon the selection of modes confirmed potential choices available to sonographers

Investigation the nonlinear optical properties of silver nanoparticles using femtosecond laser

© 2020 Published under licence by IOP Publishing Ltd. In this research, the fabrication of silver nanoparticles and experimental nonlinear response (NLO). The fabrication of the silver nanoparticles has been done using E-Beam evaporation on a glass substrate (Ag-NPs) and investigation of their nonlinear optical response (NLO). The silver nanoparticles was evaluated by optical spectrum (UV-Vis) that shows localized surface Plasmon band at 375 nm. The experiment shows the nonlinear absorption and nonlinear refraction effect of silver nanoparticles, the silver nanoparticles is analysed by Z-Scan technique using a femtoseconds laser with 800 nm wavelength. The result shows the nonlinear absorption (NLA) is at 4.8710-4cmW-1, while (NLR) is at 7.9410-9cmW-1

Investigation of enhanced double weight code in point to point access networks

© 2020 Published under licence by IOP Publishing Ltd. In this paper, an investigation and evaluation to enhanced double weight (EDW) code is performed, a new technique for code structuring and building using modified arithmetical model has been given for the code in place of employing previous technique based on Trial Inspections. Innovative design has been employed for the code into P2P networks using diverse weighted EDW code to be fitting into optical CDMA relevance applications. A new developed relation for EDW code is presented, the relation is based on studying and experimenting the effect of input transmission power with code weight, and the relation developed using numerical analysis method. This relation makes the estimation for the system input power needed more efficient. The results of the code has been explained by eye diagram and parametric illustrations from the simulated results. The result shows a magnificent performance of the code during high number of users and weight. On the other hand, the relation developed for power measurement helps to prevent power loss and consumption

GC/MS and LC-MS/MS phytochemical evaluation of the essential oil and selected secondary metabolites of Ajuga orientalis from Jordan and its antioxidant activity

The current investigation aimed to shed light in the volatile and non-volatile secondary metabolites of Ajuga orientalis L. from Jordan. GC/MS and GC/FID analysis of the hydrodistilled essential oil obtained from aerial parts of the plant revealed tiglic acid (18.90 %) as main constituent. Each of the methanol and butanol fractions of A. orientalis were screened for their total phenol content (TPC), total flavonoid content (TFC), and antioxidant activity determined by DDPH and ABTS methods. The extracts were then analyzed by LC-ESI-MS/MS to unveil their chemical constituents, especially phenols and flavonoids. Results showed that the AO-B extract had the highest TPC (217.63 ± 2.65 mg gallic acid/g dry extract), TFC (944.41 ± 4.77 mg quercetin /g dry extract), highest DPPH and ABTS antioxidant activity ((4.00 ± 0.20) × 10-2; (3.00 ± 0.20) × 10-2 mg/mL, respectively) as compared to the AO-M extract. LC-ESI-MS/MS analysis of both extracts revealed the presence of several phenolics, flavonoids and nonphenolic acids

Ballota saxatilis from Jordan: Evaluation of Essential Oil Composition and Phytochemical Profiling of Crude Extracts and Their In-Vitro Antioxidant Activity

The chemical composition of essential oil extracted from the aerial parts of Ballota saxatilis Sieber ex C.Presl from Jordan has been elucidated by gas chromatography–mass spectrometry (GC-MS). Additionally, aqueous methanol (BsA), Butanol (BsB) and water (BsW) extracts were screened for their total phenol content (TPC), total flavonoid content (TFC), and antioxidant activities using the 2,2 Diphenyl-1-picrylhydrazyl (DPPH) and 2,2-Azino-bis (3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt (ABTS) methods. The most potent extracts were screened for their phenolic acids and flavonoid content using liquid the chromatography–mass spectrometry (LC-MS) technique. The results indicated that the essential oil predominantly contained cis-pinane (14.76%), β-caryophyllene (8.91%) and allo-aromadendrene epoxide (6.39%). Among the different extracts investigated, the BsB fraction had the most TPC and TFC (455.79 ± 1.03 µg gallic acid/g dry extract; 272.62 ± 8.28 µg quercetin/g dry extract, respectively) and had the best radical and radical cation scavenging activities, as determined using the DPPH and ABTS methods. Quantitative and qualitative LC-MS analyses of BsA and BsB using LC-MS revealed each of the kaempferol-3-O-rutinoside (30.29%), chrysoeriol-7-glucoside (7.93%) and luteolin 7-o-glucoside (7.76%) as the main constituents of the BsA fraction. The BsB fraction was rich in 7,4′-dimethoxy-3-hydroxyflavone (34.68%), kaempferol-3,7,4′-trimethyl ether (29.17%) and corymbosin (9.66%) and lower concentration levels of kaempferol-3-O-rutinoside (1.63%) and chrysoeriol-7-glucoside (0.51%)

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

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

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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