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This paper addresses robust performance analysis problems of linear time-invariant (LTI) systems affected by real parametric uncertainties. These problems, known also as a special class of structured singular value computation problems, are inherently intractable (NP-hard problems). As such intensive research effort has been made to obtain computationally tractable and less conservative analysis conditions, where linear matrix inequality (LMI) plays an important. Nevertheless, since LMI-based conditions are expected to be conservative in general, it is often the case that we cannot conclude anything if the LMI at hand turns out to be infeasible. This motivates us to consider the dual of the LMI and examine the structure of the dual solution. By pursuing this direction, in this paper, we provide rank conditions on the dual solution matrix under which we can conclude that the underlying robust performance is never attained. In particular, a set of uncertain parameters that violates the specified performance can be computed. These results come from block-moment matrix structure of the dual variable, which is consistent with the recent results on polynomial optimization. This particular structure enables us to make good use of simultaneous diagonalizability property of commuting diagonalizable matrices so that the sound rank conditions for the exactness verification can be obtained. Index Terms--Block-Moment matrix structure, dual linear matrix inequalities (LMIs), exactness verification, robust performance analysis.

The development and utilization of a series of after-treatment devices in modern vehicles has led to an increase in emissions of NH3 and/or N2O with respect to the past. N2O is a long-lived greenhouse gas and an ozone-depleting substance, while NH3 is a precursor of secondary aerosols in the atmosphere. Certain regions, e.g., the EU and the USA, have introduced limits to the emissions of NH3 or N2O for vehicles tested in the laboratory. However, due to the lack of on-board systems that allow for the measurement of these compounds when the regulations were developed, these vehicles' real-world emissions have not been regulated. This work evaluates on-board systems that could allow measuring real-world emissions of NH3 and N2O from heavy-duty vehicles. In particular, emissions of NH3 or N2O from a Euro VI Step D urban/interurban bus fueled with Compressed Natural Gas were measured using the HORIBA's OBS-ONE-XL, which is based on a specifically developed technique called Infrared Laser Absorption Modulation, and uses a Quantum Cascade Laser as a light source. They were also measured using the PEMS-LAB, which is a more conventional FTIR-based system. Emissions were measured under real-world driving conditions on the road and in a climatic test cell at different ambient temperatures. For most of the conditions tested, the on-board systems correlated well with a laboratory-grade FTIR used as reference. In addition, a good correlation with R2 > 0.9 was found for the N2O concentrations measured by OBS-ONE-XL and PEMS-LAB during on-road testing. [ABSTRACT FROM AUTHOR]

Bronchogenic cysts are congenital malformations of the bronchial tree, detected as a cystic and/or mass lesion in the thoracic cavity. Although it occurs in distant locations, such as skin and retroperitoneum, to the best of our knowledge, little is known about the components and phenotypes of the epithelium that line a bronchogenic cyst in rare sites. The present study reviewed 34 bronchogenic cysts that were surgically resected at Osaka Medical and Pharmaceutical University Hospital (Osaka, Japan) from January 1998 to December 2020. Bronchogenic cysts in rare sites were detected and diagnosis was confirmed based on the presence of pseudostratified, ciliated and/or columnar epithelium together with at least one of the following: Cartilage, smooth muscle or seromucous glands. The phenotypes of epithelium lining the cyst were characterized using immunohistochemical analysis. A total of six bronchogenic cysts in rare sites (two cases each in the retroperitoneum and skin and one case each in the cervical spinal cord and pericardial cavity) met the criteria for confirmation of the diagnoses. The epithelium lining the cyst stained positive for cytokeratin CK7 and thyroid transcription factor 1 (a marker expressed in thyroid follicles and bronchial epithelium) and negative for CK20, indicating that the phenotypes were similar to those of the respiratory epithelium. The present study demonstrated that a bronchogenic cyst can occur in rare sites, such as the retroperitoneum, skin, spinal cord and pericardial cavity, suggesting that it should be considered as a differential diagnosis before surgical approach to implement relevant management modalities such as follow-up, simple or radical resection. [ABSTRACT FROM AUTHOR]

Symplocarpus nipponicus, a member of the Araceae family, is an endangered plant in several prefectures in Japan. For the conservation of this wild species, we investigated the morphology, life cycle, and genetic diversity of three wild populations. By fixed-point observation over several years, we found that it takes at least four years for the plant to set the inflorescences consisting of spadices and spathes, and another two years for it to set mature seeds. To examine the genetic diversity in the wild population, we developed 11 novel microsatellite markers and investigated the genetic variation in three populations in Kyoto Prefecture: Ayabe, Hanase, and Momoi. The Ayabe population carried less genetic variation than the other two areas, suggesting the isolation of the habitat and thus a higher risk of extinction. Our results provide basic knowledge of the ecological aspects of S. nipponicus, as well as molecular techniques for the assessment of its genetic diversity, and thus are useful for the conservation of this endangered species. [ABSTRACT FROM AUTHOR]

Objectives: The SARS-CoV-2 Alpha variant was associated with increased transmission relative to other variants present at the time of its emergence and several studies have shown an association between Alpha variant infection and increased hospitalisation and 28-day mortality. However, none have addressed the impact on maximum severity of illness in the general population classified by the level of respiratory support required, or death. We aimed to do this., Methods: In this retrospective multi-centre clinical cohort sub-study of the COG-UK consortium, 1475 samples from Scottish hospitalised and community cases collected between 1st November 2020 and 30th January 2021 were sequenced. We matched sequence data to clinical outcomes as the Alpha variant became dominant in Scotland and modelled the association between Alpha variant infection and severe disease using a 4-point scale of maximum severity by 28 days: 1. no respiratory support, 2. supplemental oxygen, 3. ventilation and 4. death., Results: Our cumulative generalised linear mixed model analyses found evidence (cumulative odds ratio: 1.40, 95% CI: 1.02, 1.93) of a positive association between increased clinical severity and lineage (Alpha variant versus pre-Alpha variants)., Conclusions: The Alpha variant was associated with more severe clinical disease in the Scottish population than co-circulating lineages., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Pascall et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)