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Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 575
Author(s):  
Manuel Kuder ◽  
Anton Kersten ◽  
Jose-Luis Marques-Lopez ◽  
Julian Estaller ◽  
Johannes Buberger ◽  
...  

This paper presents a novel capacitor voltage balancing control approach for cascaded multilevel inverters with an arbitrary number of series-connected H-Bridge modules (floating capacitor modules) with asymmetric voltages, tiered by a factor of two (binary asymmetric). Using a nearest-level reference waveform, the balancing approach uses a one-step-ahead approach to find the optimal switching-state combination among all redundant switching-state combinations to balance the capacitor voltages as quickly as possible. Moreover, using a Lyapunov function candidate and considering LaSalle’s invariance principle, it is shown that an offline calculated trajectory of optimal switching-state combinations for each discrete output voltage level can be used to operate (asymptotically stable) the inverter without measuring any of the capacitor voltages, achieving a novel sensorless control as well. To verify the stability of the one-step-ahead balancing approach and its sensorless variant, a demonstrator inverter with 33 levels is operated in grid-tied mode. For the chosen 33-level converter, the NPC main-stage and the individual H-bridge modules are operated with an individual switching frequency of about 1 kHz and 2 kHz, respectively. The sensorless approach slightly reduced the dynamic system response and, furthermore, the current THD for the chosen operating point was increased from 3.28 to 4.58 in comparison with that of using the capacitor voltage feedback.


2022 ◽  
Vol 23 (2) ◽  
pp. 716
Author(s):  
Olga Sierawska ◽  
Paulina Małkowska ◽  
Cansel Taskin ◽  
Rafał Hrynkiewicz ◽  
Paulina Mertowska ◽  
...  

In the literature, burns are understood as traumatic events accompanied by increased morbidity and mortality among affected patients. Their characteristic feature is the formation of swelling and redness at the site of the burn, which indicates the development of inflammation. This reaction is not only important in the healing process of wounds but is also responsible for stimulating the patient’s innate immune system. As a result of the loss of the protective ability of the epidermis, microbes which include bacteria, fungi, and viruses have easier access to the system, which can result in infections. However, the patient is still able to overcome the infections that occur through a cascade of cytokines and growth factors stimulated by inflammation. Long-term inflammation also has negative consequences for the body, which may result in multi-organ failure or lead to fibrosis and scarring of the skin. The innate immune response to burns is not only immediate, but also severe and prolonged, and some people with burn shock may also experience immunosuppression accompanied by an increased susceptibility to fatal infections. This immunosuppression includes apoptosis-induced lymphopenia, decreased interleukin 2 (IL-2) secretion, neutrophil storm, impaired phagocytosis, and decreased monocyte human leukocyte antigen-DR. This is why it is important to understand how the immune system works in people with burns and during infections of wounds by microorganisms. The aim of this study was to characterize the molecular pathways of cell signaling of the immune system of people affected by burns, taking into account the role of microbial infections.


2022 ◽  
pp. 1-22
Author(s):  
Bijie Yang ◽  
Ricardo F. Martinez-Botas ◽  
Yingxian Xue ◽  
Mingyang Yang

Abstract One-dimensional (1D) modelling is critical for turbomachinery unsteady performance prediction and system response assessment of internal combustion engines. This paper uses a novel 1D modelling (TURBODYNA) and proposes two additional features for the application to a twin-entry turbocharger turbine. Compared to single-entry turbines, twin-entry turbines enhance turbocharger transient response and reduce engine exhaust valve overlap periods. However, out-of-phase high frequency pulsating pressure waves lead to an unsteady mixing process from the two flows and pose great challenges to traditional 1D modelling. The present work resolves the mixing problem by directly solving mass, momentum and energy conservation equations during the mixing process instead of applying constant pressure assumption at the limb-rotor joint. Comparisons of TURBODYNA and an experimentally validated CFD suggest that TURBODYNA can not only provide a very good agreement on turbine performance, but also accurately capture unsteady features due to flow field inertial and pressure wave propagation. Levels of accuracy achieved by TURBODYNA have proved superior to traditional 1D modelling on turbine performance and the generality of the current 1D modelling has been explored by extending the application to another turbine featuring distinct characteristics.


2022 ◽  
Author(s):  
Madeleine Carruthers ◽  
Duncan E Edgley ◽  
Andrew D Saxon ◽  
Nestory P Gabagambi ◽  
Asilatu Shechonge ◽  
...  

Rapid ecological speciation along depth gradients has taken place independently and repeatedly in freshwater fishes. While the extent of genomic divergence between ecomorphs is often well understood, the molecular mechanisms facilitating such rapid diversification are typically unclear. In Lake Masoko, an East African crater lake, the cichlid Astatotilapia calliptera has diverged into shallow littoral and deep benthic ecomorphs with strikingly different jaw structures within the last 1,000 years. Using genome-wide transcriptome data from jaw tissue, we explore two major regulatory transcriptional mechanisms, expression and splicing QTL variants and examine their contribution to differential gene expression underpinning functional phenotypes. We identified 7,550 genes with significant differential expression between ecomorphs, of which 4.2% were regulated by cis-regulatory expression QTLs, and 6.4% were regulated by cis-regulatory splicing QTLs. There were also strong signals of divergent selection of differentially expressed genes that showed divergent regulation from expression, splicing or both QTL variants, including genes associated with major jaw plasticity and adaptation networks, adaptive immune system response, and oxidoreductase processes. These results suggest that transcriptome plasticity and modification have important roles during early-stage ecological speciation and demonstrate the role of regulatory-variants as important targets of selection driving ecologically-relevant divergence in gene expression that is associated with adaptive diversification.


2022 ◽  
pp. 152483802110614
Author(s):  
Sarah M. Godoy ◽  
Georgia E. Perris ◽  
Mikiko Thelwell ◽  
Antonia Osuna-Garcia ◽  
Elizabeth Barnert ◽  
...  

Nationwide efforts to enhance services for adolescents experiencing commercial sexual exploitation (CSE) in the judicial system have led to the emergence of specialty courts, including human trafficking and girls’ courts. Given that prior research has documented competing stances on the effectiveness of specialty courts for CSE-impacted populations, we conducted a systematic review of the literature to identify key characteristics of programming, profiles of adolescents served, and effectiveness of these courts. To identify relevant research and information, we systematically searched scholarly databases and information sources, conducted reference harvesting, and forwarded citation chaining. Articles presenting primary data with quantitative, qualitative, or mixed methodologies or programmatic descriptions of specialty courts serving adolescents at risk or with confirmed histories of CSE that were published after 2004 were included. We identified 39 articles on 21 specialty courts serving adolescents at risk or with confirmed histories of CSE, including seven specialty courts with evaluation or outcome data. Across specialty courts, adolescents benefited from an increase in linkage to specialized services, improved residential placement stability, and reduction in recidivism—measured by new criminal charges. Specialty court participation was also associated with improved educational outcomes and decreased instances of running away. A lack of empirical data, specifically of evaluation studies, emerged as a weakness in the literature. Still, findings support that specialty courts can be an integral judicial system response to CSE. Multidisciplinary collaboration can help target and respond to the multifaceted needs of adolescents, encourage healthy behaviors, and promote their overall wellness.


2022 ◽  
pp. 136943322110523
Author(s):  
Gökhan Çetin ◽  
Mohammed S Fadali ◽  
Gökhan Pekcan

This paper proposes a dissipative resilient observer and controller (DROC) design for a network controlled system (NCS) that handles faults, implementation errors, or cyberattacks that can be modeled as bounded controller or observer gain perturbations. It presents linear matrix inequality (LMI) conditions for the robust stability of the system in the presence of bounded perturbations in the observer and controller. Furthermore, a new LMI-based time-delay control (TDC) algorithm that mitigates the effects of perturbations due to time-delays in the NCS is introduced. The robust methodology is applied to active control of a scaled model of a structural system equipped with an active mass driver system. The results demonstrate that the proposed methodology is robust and ensures stable system response due to various types of earthquake base excitations.


Viruses ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 98
Author(s):  
Gautier Gilliaux ◽  
Daniel Desmecht

Human respiratory syncytial virus (hRSV) infection brings a wide spectrum of clinical outcomes, from a mild cold to severe bronchiolitis or even acute interstitial pneumonia. Among the known factors influencing this clinical diversity, genetic background has often been mentioned. In parallel, recent evidence has also pointed out that an early infectious experience affects heterologous infections severity. Here, we analyzed the importance of these two host-related factors in shaping the immune response in pneumoviral disease. We show that a prior gammaherpesvirus infection improves, in a genetic background-dependent manner, the immune system response against a subsequent lethal dose of pneumovirus primary infection notably by inducing a systematic expansion of the CD8+ bystander cell pool and by modifying the resident alveolar macrophages (AMs) phenotype to induce immediate cyto/chemokinic responses upon pneumovirus exposure, thereby drastically attenuating the host inflammatory response without affecting viral replication. Moreover, we show that these AMs present similar rapid and increased production of neutrophil chemokines both in front of pneumoviral or bacterial challenge, confirming recent studies attributing a critical antibacterial role of primed AMs. These results corroborate other recent studies suggesting that the innate immunity cells are themselves capable of memory, a capacity hitherto reserved for acquired immunity.


2022 ◽  
Vol 11 (1) ◽  
Author(s):  
Nada Abdelmagid ◽  
Francesco Checchi ◽  
Bayard Roberts

Abstract Background Risk communication interventions during epidemics aim to modify risk perceptions to achieve rapid shifts in population health behaviours. Exposure to frequent and often concurrent epidemics may influence how the public and health professionals perceive and respond to epidemic risks. This review aimed to systematically examine the evidence on risk perceptions of epidemic-prone diseases in countries highly vulnerable to epidemics. Methods We conducted a systematic review using PRISMA standards. We included peer-reviewed studies describing or measuring risk perceptions of epidemic-prone diseases among the general adult population or health professionals in 62 countries considered highly vulnerable to epidemics. We searched seven bibliographic databases and applied a four-stage screening and selection process, followed by quality appraisal. We conducted a narrative meta-synthesis and descriptive summary of the evidence, guided by the Social Amplification of Risk Framework. Results Fifty-six studies were eligible for the final review. They were conducted in eighteen countries and addressed thirteen epidemic-prone diseases. Forty-five studies were quantitative, six qualitative and five used mixed methods. Forty-one studies described epidemic risk perceptions in the general public and nineteen among health professionals. Perceived severity of epidemic-prone diseases appeared high across public and health professional populations. However, perceived likelihood of acquiring disease varied from low to moderate to high among the general public, and appeared consistently high amongst health professionals. Other occupational groups with high exposure to specific diseases, such as bushmeat handlers, reported even lower perceived likelihood than the general population. Among health professionals, the safety and effectiveness of the work environment and of the broader health system response influenced perceptions. Among the general population, disease severity, familiarity and controllability of diseases were influential factors. However, the evidence on how epidemic risk perceptions are formed or modified in these populations is limited. Conclusions The evidence affords some insights into patterns of epidemic risk perception and influencing factors, but inadequately explores what underlies perceptions and their variability, particularly among diseases, populations and over time. Approaches to defining and measuring epidemic risk perceptions are relatively underdeveloped. Graphical Abstract


2022 ◽  
Vol 2 (2) ◽  
pp. 222-242
Author(s):  
Zulkifli ◽  
Agustina Br Haloho ◽  
Legiran ◽  
Pirma I.R.M

Introduction: Pain is a problem often encountered in postoperative patients. Study has shown after a procedure, 80% patients experience acute pain. This postoperative pain will affect patient’s quality of life therefore necessitating quick and proper treatment. Tissue trauma during surgery will have influence on body system, including endocrine. One of endocrine system response is cortisol secretion. Cortisol levels may be attenuated by bupivacaine and oxycodone. The aim of this study was to determine the efficacy of bupivacaine0,125% and oxycodone 5 mg on pain perception measured by cortisol in patients undergoing orthopedic surgery of the lower limb. Methods: A randomized clinical trial, double-blind study was performed at Mohammad Hoesin General Hospital in Palembang, South Sumatra, from November to May 2021. There were forty samples and divided into two groups (bupivacaine 0,125% and oxycodone 5 mg). Groups were divided by block randomization by computerized random number generator. Blinding were done by making analgesic has the same packages to prevent knowledge of which intervention is being done. Data were analyzed using independent t-test, ANOVA, Mann-Whitney and Chi Square with SPSS version 22.0. Results: There were no statistically significant differences between the two groups on age, gender, body mass index and duration of surgery. In bupivacaine group, cortisol level decreased from 12.94±6.99 µg/dl to 11.32±5.42 µg/dl meanwhile oxycodone group cortisol levels increased from 11.81±8.47 µg/dl to 11.82±7.56 µg/dl. There were no significant difference between two groups relating to cortisol levels. Conclusions: No significant difference was found on administration of bupivacaine 0,125% and oxycodone 5 mg as epidural analgesia on cortisol level in postoperative orthopedic surgery of the lower limb patient.


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