Assessing the Impact of Development Disruptions and Dependencies in Analysis of Alternatives of System-of-Systems. Phase 1

2013 ◽  
Author(s):  
Daniel A. DeLaurentis ◽  
Karen Marais
Author(s):  
Mateusz Iwo Dubaniowski ◽  
Hans Rudolf Heinimann

A system-of-systems (SoS) approach is often used for simulating disruptions to business and infrastructure system networks allowing for integration of several models into one simulation. However, the integration is frequently challenging as each system is designed individually with different characteristics, such as time granularity. Understanding the impact of time granularity on propagation of disruptions between businesses and infrastructure systems and finding the appropriate granularity for the SoS simulation remain as major challenges. To tackle these, we explore how time granularity, recovery time, and disruption size affect the propagation of disruptions between constituent systems of an SoS simulation. To address this issue, we developed a high level architecture (HLA) simulation of three networks and performed a series of simulation experiments. Our results revealed that time granularity and especially recovery time have huge impact on propagation of disruptions. Consequently, we developed a model for selecting an appropriate time granularity for an SoS simulation based on expected recovery time. Our simulation experiments show that time granularity should be less than 1.13 of expected recovery time. We identified some areas for future research centered around extending the experimental factors space.


2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Joao Gabriel Rosa Ramos ◽  
Sandra Cristina Hernandes ◽  
Talita Teles Teixeira Pereira ◽  
Shana Oliveira ◽  
Denis de Melo Soares ◽  
...  

Abstract Background Clinical pharmacists have an important role in the intensive care unit (ICU) team but are scarce resources. Our aim was to evaluate the impact of on-site pharmacists on medical prescriptions in the ICU. Methods This is a retrospective, quasi-experimental, controlled before-after study in two ICUs. Interventions by pharmacists were evaluated in phase 1 (February to November 2016) and phase 2 (February to May 2017) in ICU A (intervention) and ICU B (control). In phase 1, both ICUs had a telepharmacy service in which medical prescriptions were evaluated and interventions were made remotely. In phase 2, an on-site pharmacist was implemented in ICU A, but not in ICU B. We compared the number of interventions that were accepted in phase 1 versus phase 2. Results During the study period, 8797/9603 (91.6%) prescriptions were evaluated, and 935 (10.6%) needed intervention. In phase 2, there was an increase in the proportion of interventions that were accepted by the physician in comparison to phase 1 (93.9% versus 76.8%, P < 0.001) in ICU A, but there was no change in ICU B (75.2% versus 73.9%, P = 0.845). Conclusion An on-site pharmacist in the ICU was associated with an increase in the proportion of interventions that were accepted by physicians.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Pietro Coletti ◽  
Pieter Libin ◽  
Oana Petrof ◽  
Lander Willem ◽  
Steven Abrams ◽  
...  

Abstract Background In response to the ongoing COVID-19 pandemic, several countries adopted measures of social distancing to a different degree. For many countries, after successfully curbing the initial wave, lockdown measures were gradually lifted. In Belgium, such relief started on May 4th with phase 1, followed by several subsequent phases over the next few weeks. Methods We analysed the expected impact of relaxing stringent lockdown measures taken according to the phased Belgian exit strategy. We developed a stochastic, data-informed, meta-population model that accounts for mixing and mobility of the age-structured population of Belgium. The model is calibrated to daily hospitalization data and is able to reproduce the outbreak at the national level. We consider different scenarios for relieving the lockdown, quantified in terms of relative reductions in pre-pandemic social mixing and mobility. We validate our assumptions by making comparisons with social contact data collected during and after the lockdown. Results Our model is able to successfully describe the initial wave of COVID-19 in Belgium and identifies interactions during leisure/other activities as pivotal in the exit strategy. Indeed, we find a smaller impact of school re-openings as compared to restarting leisure activities and re-openings of work places. We also assess the impact of case isolation of new (suspected) infections, and find that it allows re-establishing relatively more social interactions while still ensuring epidemic control. Scenarios predicting a second wave of hospitalizations were not observed, suggesting that the per-contact probability of infection has changed with respect to the pre-lockdown period. Conclusions Contacts during leisure activities are found to be most influential, followed by professional contacts and school contacts, respectively, for an impending second wave of COVID-19. Regular re-assessment of social contacts in the population is therefore crucial to adjust to evolving behavioral changes that can affect epidemic diffusion.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Adil Hazara ◽  
Victoria Allgar ◽  
Maureen Twiddy ◽  
Sunil Bhandari

Abstract Background and Aims Mortality rates are high in patients starting haemodialysis/haemodiafiltration (HD) therapy. Incremental HD may help reduce this risk by reducing the burden of early treatment whilst patients are still adapting to long-term HD therapy. A feasibility study (ENDURE study – Clinical trials ID: NCT04268264) is being conducted with the primary objectives of evaluating the acceptability and tolerance of a new incremental HD regime. Its secondary aims are to evaluate the impact of this form of incremental HD on indicators of patient safety and wellbeing. These indicators include blood pressure (BP) control and interdialytic weight gains (IDWG) which are independently associated with adverse cardiovascular outcomes in patients on long-term HD. We present preliminary findings from the study related to systolic BP and IDWG. Method The ENDURE study is being carried out at a tertiary care hospital in the United Kingdom. Patients aged > 18 years known to renal services for at least 90 days, referred for start of HD, were eligible for participation. Following approved consenting procedures, they are started on a new regime of incremental HD starting dialysis twice weekly with progressive increases in the duration and frequency of sessions over 15 weeks. This period is split in to four phases; phase 1 representing the first two days of dialysis (baseline) whereas phases 2 – 4 representing the pre-specified incremental steps. Propensity scores were calculated to match each participant (incremental HD group) with two controls from a database of patients who previously started HD at our centres using the standard protocol of 3 times weekly, 4hr long sessions. The matching criteria accounted for 14 key demographic, clinical and laboratory characteristics. Results were analysed as intention to treat. In comparing BP and IDWG between the two groups, only readings taken pre-dialysis at the first session of the week was considered. This study has been approved by the West of Scotland Research Ethics committee-4 (Ref: 19/WS/0019). Results Baseline characteristics of the first 15 participants (target 20) and their matched controls are presented in table 1. The proportion of females and duration of previous specialist input was higher in the incremental HD group. Conclusion The ENDURE study tests the feasibility of starting patients on a novel incremental HD regime. Early data suggest that control of systolic BP and IDWG are comparable to patients who start dialysis at 3 times weekly. Further work is needed to understand the impact of reducing dialysis frequency on BP control correlating the findings with changes residual renal function and objective measures of fluid overload.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 7042-7042
Author(s):  
Xiaofei Zhou ◽  
Diane R. Mould ◽  
Dan Zhao ◽  
Mikkael A. Sekeres ◽  
Lionel Adès ◽  
...  

7042 Background: PEV+AZA has been studied in higher-risk MDS/CMML and AML, with encouraging efficacy and an acceptable safety profile without added myelosuppression. This pooled analysis was performed to evaluate the impact of PEV exposure on safety and efficacy. Methods: Data from three studies (NCT01814826, NCT02782468 and NCT02610777) were used in the PEV exposure–safety analyses, including ≥ grade 3 neutropenia (NEU3), febrile neutropenia (FN), ≥ grade 3 thrombocytopenia, ≥ grade 3 alanine aminotransferase elevation, ≥ grade 3 aspartate aminotransferase elevation and ≥ grade 3 treatment-emergent adverse event (TEAE3), in pts with higher-risk MDS/CMML and AML who received PEV+AZA. Data from NCT02610777 were used for exposure–efficacy analyses, including overall survival (OS), event-free survival (EFS), complete response (CR) and CR+partial response (PR), in pts with higher-risk MDS/CMML who received PEV+AZA. The exposure metrics for individual pts were derived from a previously developed population pharmacokinetic model with pooled data from eight phase 1/2 studies. PEV exposure–safety relationships for the toxicity endpoints, exposure–CR and exposure–CR+PR, were estimated by logistic regression. Age, sex, race, baseline Eastern Cooperate Oncology Group (ECOG) Performance Status score and disease type were evaluated as covariates. Cox proportional-hazards models were used to evaluate the PEV exposure–survival for higher-risk MDS/CMML, with age, sex, baseline ECOG PS score, Revised International Prognostic Scoring System score (IPSS-R) and disease type as potential covariates. Results: In total, 135 pts (median age, 74 years; male, 64%; Caucasian, 82%) and 41 pts (median age, 74 years; male, 76%; Caucasian, 90%; median IPSS-R, 5.5) were included in PEV exposure–safety and exposure–efficacy analyses, respectively. PEV exposure was significantly related to the incidence of NEU3 ( p = 0.003), FN ( p = 0.02) and TEAE3 ( p = 0.02), supporting PEV dose reductions for pts with treatment-related toxicities. Relationships between PEV exposures and CR, CR+PR, EFS or OS indicated consistent clinical benefit across ranges of PEV exposure following a starting dose of 20 mg/m2. Conclusions: The association between exposure and safety supports PEV dose reductions for pts with treatment-related toxicities. The exposure–efficacy analyses indicated consistent clinical benefit across ranges of PEV exposure following a starting dose of 20 mg/m2. These results support a favorable benefit–risk profile of the 20 mg/m2 PEV dose on days 1, 3 and 5 in combination with AZA 75 mg/m2 for 7 days in 28-day cycles. Clinical trial information: NCT01814826 , NCT02782468 , NCT02610777.


2021 ◽  
Vol 11 (5) ◽  
pp. 548-556
Author(s):  
Shubhada Nayak ◽  
Madhuri Sahasrabuddhe ◽  
Sharad Kale

Anaerobic digestion is among the essential biological techniques used for stabilization of organic sludge from sewage and highly concentrated efflu-ents from food processing industries. It also recycles the municipal solid wastes into compost with simultaneous production of methane. The current study was performed to estimate the biomethanation potential of various agro- and industrial wastes like Jatropha de-oil cake, prawn shells, chicken feathers, bagasse, rice straw and wheat husk by mimicking the conditions in the biphasic Nisargruna biogas plant. A small volume of samples was chemi-cally characterized and allowed to decompose under aerobic and anaerobic conditions to determine the effect of aerobic predigestion (i.e. phase 1 of Nisargruna plant) on final methane production. The biogas produced was quantified by downward displacement of water. The observations indicated that approximately 60-80% methane was produced when Jatropha de-oil cake, prawn shells and rice straw was used. Conversely, the wheat straw and sugarcane wastes showed less methane formation, which may be due to the presence of complex polymers like lignocellulose and silica that considerably reduces the metabolic potential of microorganisms.


2021 ◽  
Vol 163 (A3) ◽  
Author(s):  
T J Newman

A common risk to personnel is from Whole Body Vibration (WBV) and shock when transiting at speed in heavy seas, and much research has been done by maritime organisations to reduce this risk and the associated health impacts. It is well known that coxswain ‘driving style’ can radically affect exposure levels for a given sea state and sustained transit speed. A data-driven approach to define what makes a good coxswain from a WBV perspective is currently being developed by the Naval Design Partnering team (NDP). In phase 1, a systematic coxswain behaviour tracking methodology has been developed and demonstrated using a motion platform-based fast craft simulator at MARIN. The performance of several experienced volunteer coxswains from MOD, RNLI and KNRM has been evaluated based on a set pattern of tests. The advantages of using the simulator, over a sea trial, have been demonstrated: it is more repeatable, more controllable, accurate and more accessible. The potential disadvantages of the approach are also discussed with reference to feedback gathered from coxswains. Analysis has shown effective throttle control is much more important than steering to reduce WBV. Several interesting trends in WBV reduction potential have been shown which it is thought, with further validation, could aid mission planning, mission execution and provide data for training autonomous feedback/control algorithms. Further work is required before the findings of this study can be fully exploited. These subsequent phases, which include sea trials, aim to provide validation and further evidence to support the initial findings.


2014 ◽  
Vol 2 (1) ◽  
pp. 1-124 ◽  
Author(s):  
Caroline L Watkins ◽  
Stephanie P Jones ◽  
Michael J Leathley ◽  
Gary A Ford ◽  
Tom Quinn ◽  
...  

BackgroundRapid access to emergency stroke care can reduce death and disability by enabling immediate provision of interventions such as thrombolysis, physiological monitoring and stabilisation. One of the ways that access to services can be facilitated is through emergency medical service (EMS) dispatchers. The sensitivity of EMS dispatchers for identifying stroke is < 50%. Studies have shown that activation of the EMSs is the single most important factor in the rapid triage and treatment of acute stroke patients.ObjectivesTo facilitate recognition of stroke by emergency medical dispatchers (EMDs).DesignAn eight-phase mixed-methods study. Phase 1: a retrospective cohort study exploring stroke diagnosis. Phase 2: semi-structured interviews exploring public and EMS interactions. Phases 3 and 4: a content analysis of 999 calls exploring the interaction between the public and EMDs. Phases 5–7: development and implementation of stroke-specific online training (based on phases 1–4). Phase 8: an interrupted time series exploring the impact of the online training.SettingOne ambulance service and four hospitals.ParticipantsPatients arriving at hospital by ambulance with stroke suspected somewhere on the stroke pathway (phases 1 and 8). Patients arriving at hospital by ambulance with a final diagnosis of stroke (phase 2). Calls to the EMSs relating to phase 1 patients (phases 3 and 4). EMDs (phase 7).InterventionsStroke-specific online training package, designed to improve recognition of stroke for EMDs.Main outcome measuresPhase 1: symptoms indicative of a final and dispatch diagnosis of stroke. Phase 2: factors involved in the decision to call the EMSs when stroke is suspected. Phases 3 and 4: keywords used by the public when describing stroke and non-stroke symptoms to EMDs. Phase 8: proportion of patients with a final diagnosis of stroke correctly dispatched as stroke by EMDs.ResultsPhase 1: for patients with a final diagnosis of stroke, facial weakness and speech problems were significantly associated with an EMD code of stroke. Phase 2: four factors were identified – perceived seriousness; seeking and receiving lay or professional advice; caller’s description of symptoms and emotional response to symptoms. Phases 3 and 4: mention of ‘stroke’ or one or more Face Arm Speech Test (FAST) items is much more common in stroke compared with non-stroke calls. Consciousness level was often difficult for callers to determine and/or communicate. Phase 8: there was a significant difference (p = 0.003) in proportions correctly dispatched as stroke – before the training was implemented 58 out of 92 (63%); during implementation of training 42 out of 48 (88%); and after training implemented 47 out of 59 (80%).ConclusionsEMDs should be aware that callers are likely to describe loss of function (e.g. unable to grip) rather than symptoms (e.g. weakness) and that callers using the word ‘stroke’ or describing facial weakness, limb weakness or speech problems are likely to be calling about a stroke. Ambiguities and contradictions in dialogue about consciousness level arise during ambulance calls for suspected and confirmed stroke. The online training package improved recognition of stroke by EMDs. Recommendations for future research include testing the effectiveness of the Emergency Stroke Calls: Obtaining Rapid Telephone Triage (ESCORTT) training package on the recognition of stroke across other EMSs in England; and exploring the impact of the early identification of stroke by call handlers on patient and process outcomes.FundingThe National Institute for Health Research Programme Grants for Applied Research programme.


2022 ◽  
Author(s):  
Sofia Schön ◽  
Ludvig Knöös Franzén ◽  
Carina Marcus ◽  
Kristian Amadori ◽  
Christopher Jouannet ◽  
...  

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