Robust Stabilization via Super-Stable Systems Techniques

In this paper, we propose a direct method for the synthesis of robust systems operating under parametric uncertainty of the control plant model. The developed robust control procedures are based on the assumption that the structural properties of the nominal system are conservated over the entire range of parameter changes. The invariant-to-parametric-uncertainties transformation of the initial model to a regular form makes it possible to use the concept of super-stable systems for the synthesis of a stabilizing feedback. It is essential that the synthesis of super-stable systems is carried out not on the basis of assigning eigenvalues to the matrix of the close-loop system, but in terms of its elements. The proposed approach is applicable to a wide class of linear systems with parametric uncertainties and provides a given degree of stability.

Interferon-γ-Inducible Protein 10 (IP-10) Kinetics after Antiretroviral Treatment Initiation in Ethiopian Adults with HIV

To reach the goal of elimination of HIV as public health threat, access to antiretroviral treatment (ART) has to be further scaled up. To ensure viral suppression in individuals receiving ART, novel and robust systems for treatment monitoring are required.

Autonomous vehicles for micro-mobility

Autonomous vehicles have been envisioned for more than 100 years. One of the first suggestions was a front cover of Scientific America back in 1916. Today, it is possible to get cars that drive autonomously for extended distances. We are also starting to see micro-mobility solutions, such as the Nuro vehicles for pizza delivery. Building autonomous cars that can operate in urban environments with a diverse set of road-users is far from trivial. Early 2018 the Contextual Robotics Institute at UC San Diego launched an effort to build a full stack autonomous vehicle for micro-mobility. The motivations were diverse: i) development of a system for operation in an environment with many pedestrians, ii) design of a system that does not rely on dense maps (or HD-maps as they are sometimes named), iii) design strategies to build truly robust systems, and iv) a framework to educate next-generation engineers. In this paper, we present the research effort of design, prototyping, and evaluation of such a vehicle. From the evaluation, several research directions are explored to account for shortcomings. Lessons and issues for future work are additionally drawn from this work.

The Hybrid-Agile Design of Experiments Methodology

A DOE (Design of Experiments) is the laying out of a detailed experimental plan in advance of doing the experiment. Optimal DOEs maximize the amount of information that can be obtained for a given amount of experimental effort. The traditional DOE methodology is waterfall-type methodology implying a sequential and linear life-cycle process. The success of the experiment and usefulness of the results are highly dependent on the initial experimental setup and assumptions, and does not allow to go back and change something that was not well-documented or thought upon in the design stage. The fast-changing software development industry have made it understandable that the traditional waterfall methodology for developing systems, which follows similar patters to the traditional DOE, lacks the agility required for developing robust systems. These limitations have triggered the development of agile: a type of incremental model of software development based on principles that focuses more on flexible responses to change, instead of in-depth planning at the design stage. This paper proposes the hybrid-agile DOE methodology – a methodology that incorporates agile principles in traditional waterfall DOE methodologies – to design effective experimental layouts that allow for improvement during the experimental trial process. The methodology is applied to the natural ageing of adhesives tapes for building applications. This methodology can overcome traditional DOE, by adding agility in the whole process, especially in cases where the investigated products lack prior information and are characterised by large variability.

1161 Streamlining the Patient Journey for Operative Management During COVID 19

Aim Leeds, UK is a high-volume acute surgery unit. Emergency operating was drastically affected by the pandemic and time from admission to definitive procedure significantly increased. This intervention aimed to streamline the patient journey from acute admission to the operating theatre. Method An audit considering delays to transfer, theatre access and recovery discharge, along with the criteria used for ‘Hot’ theatre was undertaken. Data was collected prospectively between 02/06/2020-06/07/2020 via a standardised proforma. Preliminary results suggested a geographically remote ‘hot’ theatre was associated with multi-factorial delays so was relocated to more familiar surroundings. This was re-audited between 06/07/2020-06/08/2020 aiming to characterise factors contributing to delay. A dedicated in-hours acute theatres porter was introduced for a trial period. Data was collected retrospectively between 24/08/2020-14/09/2020 and prospectively between 14/09-05/10/2020 via hospital electronic systems. Results Initially the average time from patient transfer to leaving theatre recovery was 4h6m55s (N = 52). Relocating theatres reduced this to 2h48m04s (N = 74)- an average reduction of 1h18m51s. The greatest reduction was seen in anaesthetic time between 1h17m54s to 41m29s. The introduction of a dedicated porter reduced the average transfer time to theatre from 36 minutes (N = 53) to 21 minutes (N = 68) (p < 0.05). Conclusions Delay to theatre has a high cost financially and in its effect on patient outcomes. Delays are often multifactorial and robust systems are essential to minimise delays. Patients are best served by well-trained, dedicated ‘Acute’ team in familiar surroundings. Long-term implementation of dedicated portering service will save time, money and improve patient care.

Applying DEFCON and the Homeland Security Advisory System in organisational risk management

Many businesses face avoidable strategic and external risks that can be addressed by accepting, relocating, reducing, or eliminating them. Companies of all sizes should predict and prepare for the risks that come with doing business. When a scenario becomes a reality, a well-prepared organisation can mitigate sales, lost time and productivity, and negative impact on customers. They can assist in the safety of an organisation and its employees by offering a fully integrated threat management system that offers real-time threat impact assessments that the corporation can use to fulfil its duty of care obligations and keep employees safe. These systems are based on robust systems such as DEFCON, HSAS, and NTAS. In analogy to the application in Military and Anti-Terrorism, the systems DEFCON, HSAS or NTAS to the specific application, define the comprehensive explanations and define corresponding actions at each threat level. This article deals with the question, if the deployment of DEFCON, HSAS/NTAS is a suitable approach to meet the requirements of the ISO 9001:2015. To answer the given research-question the method of qualitative content analysis was used as outlined by Mayring. Six main codes and twelve subcodes were defined inductively and deductively, and the present literature was encoded according to the method of structured content analysis. To this end, 765 codings were carried out and then analysed in the context of the research questions. As a result, the research question was confirmed by the present study.

Cell Line Platforms Support Research into Arthropod Immunity

Innate immune responses are essential to maintaining insect and tick health and are the primary defense against pathogenic viruses, bacteria, and fungi. Cell line research is a powerful method for understanding how invertebrates mount defenses against pathogenic organisms and testing hypotheses on how these responses occur. In particular, immortal arthropod cell lines are valuable tools, providing a tractable, high-throughput, cost-effective, and consistent platform to investigate the mechanisms underpinning insect and tick immune responses. The research results inform the controls of medically and agriculturally important insects and ticks. This review presents several examples of how cell lines have facilitated research into multiple aspects of the invertebrate immune response to pathogens and other foreign agents, as well as comments on possible future research directions in these robust systems.

Designing Robust Systems Using Bioinspired Product Architecture

This work analyzes the role of bioinspired product architecture in facilitating the development of robust engineering systems. Existing studies on bioinspired product architecture largely focus on inspiring biology-like function-sharing in engineering design. This work shows that the guidelines for bioinspired product architecture, originally developed for bioinspiration of function-sharing, may induce robustness to random failures in engineered systems. To quantify such an improvement, this study utilizes Functional Modeling to derive modular equivalents of biological systems. The application of the bioinspired product architecture guidelines is then modeled as a transition from the modular product architecture of the modular equivalents to the actual product architecture of the biological systems. The robustness of the systems to random failures is analyzed after the application of each guideline by modeling the systems as directed networks. A singular robustness metric is then introduced to quantify the degradation in the expected functionality of systems upon increasing severity of random disruptions. Our results show that a system with bioinspired product architecture exhibits a gradual degradation in expected functionality upon increasing the number of failed modules as compared to an equivalent system with a one-to-one mapping of functions to modules. The findings are validated by designing and analyzing a COVID-19 breathalyzer as a case study.

Attenuated SIRT1 Activity Leads to PER2 Cytoplasmic Localization and Dampens the Amplitude of Bmal1 Promoter-Driven Circadian Oscillation

The circadian clock possesses robust systems to maintain the rhythm approximately 24 h, from cellular to organismal levels, whereas aging is known to be one of the risk factors linked to the alternation of circadian physiology and behavior. The amount of many metabolites in the cells/body is altered with the aging process, and the most prominent metabolite among them is the oxidized form of nicotinamide adenine dinucleotide (NAD+), which is associated with posttranslational modifications of acetylation and poly-ADP-ribosylation status of circadian clock proteins and decreases with aging. However, how low NAD+ condition in cells, which mimics aged or pathophysiological conditions, affects the circadian clock is largely unknown. Here, we show that low NAD+ in cultured cells promotes PER2 to be retained in the cytoplasm through the NAD+/SIRT1 axis, which leads to the attenuated amplitude of Bmal1 promoter-driven luciferase oscillation. We found that, among the core clock proteins, PER2 is mainly affected in its subcellular localization by NAD+ amount, and a higher cytoplasmic PER2 localization was observed under low NAD+ condition. We further found that NAD+-dependent deacetylase SIRT1 is the regulator of PER2 subcellular localization. Thus, we anticipate that the altered PER2 subcellular localization by low NAD+ is one of the complex changes that occurs in the aged circadian clock.