Abstract
Background
To evaluate the effect of screening for sepsis using an electronic sepsis alert vs. no alert in hospitalized ward patients on 90-day in-hospital mortality.
Methods
The SCREEN ...trial is designed as a stepped-wedge cluster randomized controlled trial. Hospital wards (total of 45 wards, constituting clusters in this design) are randomized to have active alert vs. masked alert, 5 wards at a time, with each 5 wards constituting a sequence. The study consists of ten 2-month periods with a phased introduction of the intervention. In the first period, all wards have a masked alert for 2 months. Afterwards the intervention (alert system) is implemented in a new sequence every 2-month period until the intervention is implemented in all sequences. The intervention includes the implementation of an electronic alert system developed in the hospital electronic medical records based on the quick sequential organ failure assessment (qSOFA). The alert system sends notifications of “possible sepsis alert” to the bedside nurse, charge nurse, and primary medical team and requires an acknowledgment in the health information system from the bedside nurse and physician. The calculated sample size is 65,250. The primary endpoint is in-hospital mortality by 90 days.
Discussion
The trial started on October 1, 2019, and is expected to complete patient follow-up by the end of October 2021.
Trial registration
ClinicalTrials.gov
NCT04078594
. Registered on September 6, 2019
Background It is unclear whether screening for sepsis using an electronic alert in hospitalized ward patients improves outcomes. The objective of the Stepped-wedge Cluster Randomized Trial of ...Electronic Early Notification of Sepsis in Hospitalized Ward Patients (SCREEN) trial is to evaluate whether an electronic screening for sepsis compared to no screening among hospitalized ward patients reduces all-cause 90-day in-hospital mortality. Methods and design This study is designed as a stepped-wedge cluster randomized trial in which the unit of randomization or cluster is the hospital ward. An electronic alert for sepsis was developed in the electronic medical record (EMR), with the feature of being active (visible to treating team) or masked (inactive in EMR frontend for the treating team but active in the backend of the EMR). Forty-five clusters in 5 hospitals are randomized into 9 sequences of 5 clusters each to receive the intervention (active alert) over 10 periods, 2 months each, the first being the baseline period. Data are extracted from EMR and are compared between the intervention (active alert) and control group (masked alert). During the study period, some of the hospital wards were allocated to manage patients with COVID-19. The primary outcome of all-cause hospital mortality by day 90 will be compared using a generalized linear mixed model with a binary distribution and a log-link function to estimate the relative risk as a measure of effect. We will include two levels of random effects to account for nested clustering within wards and periods and two levels of fixed effects: hospitals and COVID-19 ward status in addition to the intervention. Results will be expressed as relative risk with a 95% confidence interval. Conclusion The SCREEN trial provides an opportunity for a novel trial design and analysis of routinely collected and entered data to evaluate the effectiveness of an intervention (alert) for a common medical problem (sepsis in ward patients). In this statistical analysis plan, we outline details of the planned analyses in advance of trial completion. Prior specification of the statistical methods and outcome analysis will facilitate unbiased analyses of these important clinical data. Trial registration ClinicalTrials.gov NCT04078594. Registered on September 6, 2019 Keywords: Sepsis, Alert, Screening, qSOFA, Mortality, Electronic medical records
Abstract
Background
It is unclear whether screening for sepsis using an electronic alert in hospitalized ward patients improves outcomes. The objective of the Stepped-wedge Cluster Randomized Trial ...of Electronic Early Notification of Sepsis in Hospitalized Ward Patients (SCREEN) trial is to evaluate whether an electronic screening for sepsis compared to no screening among hospitalized ward patients reduces all-cause 90-day in-hospital mortality.
Methods and design
This study is designed as a stepped-wedge cluster randomized trial in which the unit of randomization or cluster is the hospital ward. An electronic alert for sepsis was developed in the electronic medical record (EMR), with the feature of being active (visible to treating team) or masked (inactive in EMR frontend for the treating team but active in the backend of the EMR). Forty-five clusters in 5 hospitals are randomized into 9 sequences of 5 clusters each to receive the intervention (active alert) over 10 periods, 2 months each, the first being the baseline period. Data are extracted from EMR and are compared between the intervention (active alert) and control group (masked alert). During the study period, some of the hospital wards were allocated to manage patients with COVID-19. The primary outcome of all-cause hospital mortality by day 90 will be compared using a generalized linear mixed model with a binary distribution and a log-link function to estimate the relative risk as a measure of effect. We will include two levels of random effects to account for nested clustering within wards and periods and two levels of fixed effects: hospitals and COVID-19 ward status in addition to the intervention. Results will be expressed as relative risk with a 95% confidence interval.
Conclusion
The SCREEN trial provides an opportunity for a novel trial design and analysis of routinely collected and entered data to evaluate the effectiveness of an intervention (alert) for a common medical problem (sepsis in ward patients). In this statistical analysis plan, we outline details of the planned analyses in advance of trial completion. Prior specification of the statistical methods and outcome analysis will facilitate unbiased analyses of these important clinical data.
Trial registration
ClinicalTrials.gov
NCT04078594
. Registered on September 6, 2019
Ni-based super alloy Inconel-718 is ubiquitous in metal 3D printing where a high cooling rate and thermal gradient are present. These manufacturing conditions are conducive to high initial ...dislocation density and porosity or voids in the material. This work proposes a molecular dynamics (MD) analysis method that can examine the role of dislocations, cooling rates, voids, and their interactions governing the material properties and failure mechanisms in Inconel-718 using the Embedded Atom Method (EAM) potential. Throughout this work, three different structures - nanowires (NWs), nanopillars (NPs), and thin-plates - are used. The strain rate is varied from 10
8
s
−1
to 10
10
s
−1
and the temperature is varied from 100 K to 800 K. Different cooling rates ranging from 0.5 × 10
10
K s
−1
to 1 × 10
14
K s
−1
are applied. Our results suggest that the high cooling rates create regular crystalline structures which result in high strength and ductility. In contrast, the lower cooling rates form a non-crystalline structure that exhibits low strength and a brittle nature. This brittle to ductile transition is observed solely due to the cooling rate at the nanoscale. Elimination of voids as a result of heat treatment is reported as well. Shockley dislocation is observed as the key factor during tensile plastic deformation. Increasing strain rates result in strain hardening and a higher dislocation density in tension. Our computational method is successful in capturing extensive sliding on the {111} shear plane due to dislocation, which leads to necking before fracture. Furthermore, notable mechanical properties are revealed by varying the temperature, size and strain rate. Our results detail a pathway to design machine parts with Inconel-718 alloy efficiently in a bottom-up approach.
Our atomistic study reveals the deformation mechanism of Inconel-718 using dislocation physics under different types of loading. The cooling rates used during the heat treatment largely determine the mode of fracture (brittle or ductile) of the alloy.
Dermoscopic images ideally depict pigmentation attributes on the skin surface which is highly regarded in the medical community for detection of skin abnormality, disease or even cancer. The ...identification of such abnormality, however, requires trained eyes and accurate detection necessitates the process being time-intensive. As such, computerized detection schemes have become quite an essential, especially schemes which adopt deep learning tactics. In this paper, a convolutional deep neural network, S2C-DeLeNet, is proposed, which (i) Performs segmentation procedure of lesion based regions with respect to the unaffected skin tissue from dermoscopic images using a segmentation sub-network, (ii) Classifies each image based on its medical condition type utilizing transferred parameters from the inherent segmentation sub-network. The architecture of the segmentation sub-network contains EfficientNet-B4 backbone in place of the encoder and the classification sub-network bears a ‘Classification Feature Extraction’ system which pulls trained segmentation feature maps towards lesion prediction. Inside the classification architecture, there have been designed, (i) A ‘Feature Coalescing Module’ in order to trail and mix each dimensional feature from both encoder and decoder, (ii) A ‘3D-Layer Residuals’ block to create a parallel pathway of low-dimensional features with high variance for better classification. After fine-tuning on a publicly accessible dataset, a mean dice-score of 0.9494 during segmentation is procured which beats existing segmentation strategies and a mean accuracy of 0.9103 is obtained for classification which outperforms conventional and noted classifiers. Additionally, the already fine-tuned network demonstrates highly satisfactory results on other skin cancer segmentation datasets while cross-inference. Extensive experimentation is done to prove the efficacy of the network for not only dermoscopic images but also different medical modalities; which can show its potential in being a systematic diagnostic solution in the field of dermatology and possibly more.
Semiconducting nanowires (NWs), key building blocks in nanotechnology with many potential applications, are stirring the attention of the scientific world because of their many unique properties. ...Cadmium telluride (CdTe) single crystal nanowires, with Zinc Blende (ZB) crystal configuration, have become the focus of interest nowadays due to its promising application in Opto-electro-mechanical nanodevices. However, due to the lack of complete insight into their mechanical deformation, it is necessary to thoroughly study the CdTe nanowires. In this study, molecular dynamics simulations have been used to investigate the mechanical behavior of CdTe nanowires (NWs) by varying size, temperature, crystal orientation, and strain rate under tension and compression. Results show that the fracture strength of the 111-oriented CdTe NWs is always higher than that of the 110-oriented CdTe NWs under tension whereas, in compression, the fracture strength of the 111-oriented CdTe NWs is significantly lower than that of the 110-oriented CdTe NWs. Moreover, upon applying the tensile load along NWs growth direction, the 111-oriented CdTe NWs fail by creating void in 10-1 direction due to bond breaking in 1-21 direction regardless of temperature and NW size. Under compression, the 111-oriented nanowires show buckling and plasticity. It has also been observed that size has a negligible effect on the tensile behavior but in compression, the behavior is size-dependent. Both tensile and compressive strengths show an inverse relation with temperature. Finally, the impact of strain rate on 111-oriented CdTe NWs are also studied where higher fracture strengths and strains at higher strain rates have been found under both tension and compression. With increasing the strain rate, the number of voids is also increased in the NWs. This study will help to design CdTe NWs based devices efficiently by presenting an in-depth understanding of the failure behavior of the 111-oriented CdTe NWs.
Gold–Silver (Au–Ag) core-shell nanostructures have significant applicability in stretchable and biocompatible electronics where endurance under high tensile and cyclic loading is a requirement. This ...work, for the first time, quantitatively investigates the role of dislocations and defect interaction governing the mechanical behavior of Au–Ag and Ag–Au Core-shell nanostructures under tensile and cyclic loading using molecular dynamics (MD) simulation. For accurate representation of the underlying physics, a novel modified embedded atomic model (MEAM) interatomic potential for pristine Au, Ag and their alloys is parameterized through two different density functional theory (DFT) schemes. Using the new potential for MD simulations, the cyclic loading properties of pristine and core-shell nanowires (NWs) in a strain range of −15%–15% for 10 cycles are conducted. The tensile behavior of pristine and core-shell NWs is also explored for temperatures between 300 K and 600 K. A comparative analysis between Core-shell structures and their pristine counterparts are carried out. Our results suggest that Ag–Au Core-shell NW exhibit superior stress-strain reversibility under cyclic loading among the structures examined. Ag–Au exhibit the highest dislocation formation and near-complete annihilation of defects consistently. Au–Ag also present improved cyclic loading properties than its pristine counterparts. For tensile loading, all four structures exhibited deterioration in strength with increasing temperature. Thermal softening is observed to be more prominent in Au–Ag core-shell NWs compared to Ag–Au. Our work lays out a foundation for exploration of mechanical properties of Au–Ag systems using the MEAM potential which will help design components for stretchable electronics and creates a pathway for further exploration of similar binary alloy systems.
•Develops a new MEAM potential for cyclic loading of Ag–Au composite nanowire.•Presents detail methods and final LAMMPS compatible MEAM forcefield for general reader.•Observes the role of dislocation on the failure mechanism in reversible loading of Au–Ag nanowire.•Effects of composition and temperature on the failure mechanism are observed in details.
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