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Collaborative Cyber-Physical Systems (CCPS) are systems that contain tightly coupled physical and cyber components, massively interconnected subsystems, and collaborate to achieve a common goal. The safety of a single Cyber-Physical System (CPS) can be achieved by following the safety standards such as ISO 26262 and IEC 61508 or by applying hazard analysis techniques. However, due to the complex, highly interconnected, heterogeneous, and collaborative nature of CCPS, a fault in one CPS's components can trigger many other faults in other collaborating CPSs. Therefore, a safety assurance technique based on fault criticality analysis would require to ensure safety in CCPS. This paper presents a Fault Criticality Matrix (FCM) implemented in our tool called CPSTracer, which contains several data such as identified fault, fault criticality, safety guard, etc. The proposed FCM is based on composite hazard analysis and content-based relationships among the hazard analysis artifacts, and ensures that the safety guard controls the identified faults at design time; thus, we can effectively manage and control the fault at the design phase to ensure the safe development of CPSs. To validate our approach, we introduce a case study on the Platooning system (a collaborative CPS). We perform the criticality analysis of the Platooning system using FCM in our developed tool. After the detailed fault criticality analysis, we investigate the results to check the appropriateness and effectiveness with two research questions. Also, by performing simulation for the Platooning, we showed that the rate of collision of the Platooning system without using FCM was quite high as compared to the rate of collisions of the system after analyzing the fault criticality using FCM., Comment: This paper is an extended version of an article submitted to KCSE-2021

Molecular imprinting technology is based on incorporating template molecules in the polymer matrix, followed by their extraction to leave specific cavities similar in shape and size to the incorporated template molecules. The resultant molecularly imprinted polymers (MIPs) then show antibody-like and enzyme-like behavior. MIPs are used as selective adsorbents, stationary phases, sensors, drug delivery agents, ultrafiltration systems, catalysts, etc. To achieve a specific function, MIPs are synthesized in various forms like beads, particles, membranes, fibers and composites. MIP beads and particles have prime importance due to their use in multiple applications. In this article, we present a survey of various polymerization techniques used for the synthesis of MIP beads and particles, along with a special focus on the studies presenting their use in separation and purification.

Adaptation to changing environmental conditions is a driver of plant diversification. Elevational gradients offer a unique opportunity for investigating adaptation to a range of climatic conditions. The use of specialized metabolites as volatile and phenolic compounds is a major adaptation in plants, affecting their reproductive success and survival by attracting pollinators and protecting themselves from herbivores and other stressors. The wormseed Artemisia brevifolia can be found across multiple elevations in the Western Himalayas, a region that is considered a biodiversity hotspot and is highly impacted by climate change. This study aims at understanding the volatile and phenolic compounds produced by A. brevifolia in the high elevation cold deserts of the Western Himalayas with the view to understanding the survival strategies employed by plants under harsh conditions. Across four sampling sites with different elevations, polydimethylsiloxane (PDMS) sampling and subsequent GCMS analyses showed that the total number of volatile compounds in the plant headspace increased with elevation and that this trend was largely driven by an increase in compounds with low volatility, which might improve the plant’s resilience to abiotic stress. HPLC analyses showed no effect of elevation on the total number of phenolic compounds detected in both young and mature leaves. However, the concentration of the majority of phenolic compounds decreased with elevation. As the production of phenolic defense compounds is a costly trait, plants at higher elevations might face a trade-off between energy expenditure and protecting themselves from herbivores. This study can therefore help us understand how plants adjust secondary metabolite production to cope with harsh environments and reveal the climate adaptability of such species in highly threatened regions of our planet such as the Himalayas.

Objectives To develop and validate the Urethroplasty Training and Assessment Tool (UTAT) using Healthcare Failure Mode and Effect Analysis (HFMEA) for training and assessment of urology trainees learning this urethral reconstruction technique, as urethroplasty is the 'gold standard' treatment for long and recurrent urethral strictures and with a variety of techniques and a lack of standardised reconstructive curricula, there is a need for procedure-specific training tools to improve surgeon training and patient safety. Materials and methods This international observational study was performed over an 11-month period. The HFMEA was used to identify and evaluate hazardous stages of urethroplasty to develop the UTAT. Hazard scores were calculated for the included steps of urethroplasty. Content validation was performed by 12 expert surgeons and multidisciplinary teams from international tertiary centres. Results The HFMEA process resulted in an internationally validated UTAT. Hazard scores ≥4 and single point weaknesses were included to implement actions and outcome measures. Content validation was achieved by circulating the process map, hazard analysis table, and developed tools. Changes were implemented based on the feedback received from expert surgeons. The content validated dorsal onlay buccal mucosa graft bulbar UTAT contained five phases, 10 processes and 23 sub-processes. Conclusions The modular UTAT offers a comprehensive validated training tool developed via a detailed HFMEA protocol. This may be utilised to standardise the training and assessment of urology trainees.

The deep neural networks (DNNs)based autonomous driving systems (ADSs) are expected to reduce road accidents and improve safety in the transportation domain as it removes the factor of human error from driving tasks. The DNN based ADS sometimes may exhibit erroneous or unexpected behaviors due to unexpected driving conditions which may cause accidents. It is not possible to generalize the DNN model performance for all driving conditions. Therefore, the driving conditions that were not considered during the training of the ADS may lead to unpredictable consequences for the safety of autonomous vehicles. This study proposes an autoencoder and time series analysis based anomaly detection system to prevent the safety critical inconsistent behavior of autonomous vehicles at runtime. Our approach called DeepGuard consists of two components. The first component, the inconsistent behavior predictor, is based on an autoencoder and time series analysis to reconstruct the driving scenarios. Based on reconstruction error and threshold it determines the normal and unexpected driving scenarios and predicts potential inconsistent behavior. The second component provides on the fly safety guards, that is, it automatically activates healing strategies to prevent inconsistencies in the behavior. We evaluated the performance of DeepGuard in predicting the injected anomalous driving scenarios using already available open sourced DNN based ADSs in the Udacity simulator. Our simulation results show that the best variant of DeepGuard can predict up to 93 percent on the CHAUFFEUR ADS, 83 percent on DAVE2 ADS, and 80 percent of inconsistent behavior on the EPOCH ADS model, outperforming SELFORACLE and DeepRoad. Overall, DeepGuard can prevent up to 89 percent of all predicted inconsistent behaviors of ADS by executing predefined safety guards., Comment: 22 pages

INTRODUCTION AND OBJECTIVE:Urethroplasty is regarded as the gold standard in urethral stricture management. It is technically difficult with expertise only available in selected centres worldwide. ...

To develop and validate the Urethroplasty Training and Assessment Tool (UTAT) using Healthcare Failure Mode and Effect Analysis (HFMEA) for training and assessment of urology trainees learning this urethral reconstruction technique, as urethroplasty is the 'gold standard' treatment for long and recurrent urethral strictures and with a variety of techniques and a lack of standardised reconstructive curricula, there is a need for procedure-specific training tools to improve surgeon training and patient safety.This international observational study was performed over an 11-month period. The HFMEA was used to identify and evaluate hazardous stages of urethroplasty to develop the UTAT. Hazard scores were calculated for the included steps of urethroplasty. Content validation was performed by 12 expert surgeons and multidisciplinary teams from international tertiary centres.The HFMEA process resulted in an internationally validated UTAT. Hazard scores ≥4 and single point weaknesses were included to implement actions and outcome measures. Content validation was achieved by circulating the process map, hazard analysis table, and developed tools. Changes were implemented based on the feedback received from expert surgeons. The content validated dorsal onlay buccal mucosa graft bulbar UTAT contained five phases, 10 processes and 23 sub-processes.The modular UTAT offers a comprehensive validated training tool developed via a detailed HFMEA protocol. This may be utilised to standardise the training and assessment of urology trainees.

Mutational status of 40 parents of beta-thalassemia patients recruited for initial evaluation of HRM study. (DOCX 11 kb)

The investigation of intermolecular hydrogen bonding between the luminescent polypyrene covalent organic framework and formaldehyde (PPy-COF-HCHO) was carried out with the density functional theory and time-dependent density functional theory. The strengthening of the photoexcited hydrogen bond C = O---H–C was verified via geometric structures, electronic transition energies, binding energies, UV-Vis and infrared spectra comparison in both ground state and excited state of the PPy-COF's truncated representative fragment. From the frontier molecular orbitals examination, natural population analysis, and plotted electron density difference map demonstrated that the strengthened hydrogen bond facilitated the rearrangement of electron density between H-donor and H-acceptor moieties which should account for charge transfer and ultimate fluorescence quenching. Interestingly, the energy gap between excited state and triplet state of the hydrogen-bonded complex showed the possibility of the intersystem crossing. The MOMAP programme further confirmed the quenching process because there was a lower fluorescent rate constant for the donor–acceptor PPy-COF-HCHO complex compared to free PPy-COF fragment. Results above significantly highlighted the high sensitivity of the PPy-COF towards organic analyte, i.e. the formaldehyde and can be employed as a sensor.

This paper details the evolution of hydraulic fracture design, execution, and evaluation in the Angsi field, Offshore Malaysia. The primary target for propped hydraulic fracturing treatments is a 660 ft thick series of stacked fluvial sandstones at an average depth of 8500 ft-TVD, designated the K-sands. The K-sands are high temperature (320ºF), over-pressured retrograde gas condensate reservoirs ranging from 10 to 90 ft net thickness and 0.1 to 3 mD. Multi-staged propped hydraulic fracture treatments are required to improve well deliverability and to mitigate the detrimental effects of condensate dropout on well performance. The initial treatment screened out very early in the job. Fortunately, extensive diagnostic data were gathered to evaluate the treatment – including temperature and radioactive tracer logs, mini-fracs with real-time BHP and BHT, memory gauges that provided accurate BHP data for the propped treatment, and comprehensive fluid QC and rheology (Fann 50 on the platform). The integration of the diagnostic data with fracture modeling and engineering analyses indicated that the screen-out was caused by a combination of complex fracture growth and low fluid viscosity. The Angsi treatment strategy was subsequently changed to mitigate and control the problems associated with complex fracture growth, which included increasing fluid viscosity, using proppant slugs, and optimizing the perforation placement. The changes in treatment strategy implemented after the initial early screen-out resulted in the successful placement of 38 of the subsequent 41 treatments (93% success). Success is defined as placing 90% or more of the designed proppant volume. Fracturing operations were significantly improved with the introduction of "live annulas" fracturing after the initial well, resulting in cost savings of at least U.S. $10 million in the first year. Live annulus fracturing also provided "real-time" BHP measurement that resulted in better treatment control and evaluation. Treatment designs were continuously improved throughout the program, increasing both fracture length and conductivity and improving K-sand interval coverage. The success of the first phase of the fracturing program resulted in gas production of over 190 MMCFD initial capacity and 8,200 BCPD.