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Enhanced Solar Photovoltaic System Management and Integration:The Digital Twin Concept
Get PDFThe rapid acceptance of solar photovoltaic (PV) energy across various countries has created a pressing need for more coordinated approaches to the sustainable monitoring and maintenance of these widely distributed installations. To address this challenge, several digitization architectures have been proposed, with one of the most recently applied being the digital twin (DT) system architecture. DTs have proven effective in predictive maintenance, rapid prototyping, efficient manufacturing, and reliable system monitoring. However, while the DT concept is well established in fields like wind energy conversion and monitoring, its scope of implementation in PV remains quite limited. Additionally, the recent increased adoption of autonomous platforms, particularly robotics, has expanded the scope of PV management and revealed gaps in real-time monitoring needs. DT platforms can be redesigned to ease such applications and enable integration into the broader energy network. This work provides a system-level overview of current trends, challenges, and future opportunities for DTs within renewable energy systems, focusing on PV systems. It also highlights how advances in artificial intelligence (AI), the internet-of-Things (IoT), and autonomous systems can be leveraged to create a digitally connected energy infrastructure that supports sustainable energy supply and maintenance
Closed-Loop Shape-Forming Control of a Magnetic Soft Continuum Robot
Get PDFContinuum manipulators are frequently employed in endoluminal interventions, however, a lack of softness and dexterity in standard manipulators can risk trauma during navigation and limit reachable workspace. Magnetically actuated Soft Continuum Robots (MSCRs) offer enhanced miniaturization potential and reduced rigidity due to their external actuation. Magnetizations pertaining only to the tip of the robot offer a limited range of deformation options where more versatile MSCRs can be embedded with distinct, lengthwise magnetization profiles. These full-body bespoke profiles allow the robots to form pre-determined shapes under actuation. Here we propose an approach to model and control MSCR behavior in closed-loop. We employ this system to achieve shape forming navigations subject to variations in initial conditions. To validate our methodology, we conduct experiments using a 50 mm long by 1.8 mm diameter MSCR navigating through a soft phantom from the tip of a duodenoscope. The proposed system is capable of rejecting variations in the angle at which the MSCR is inserted. We employed homogeneous magnetic fields for actuation and closed-loop vision-based control to manipulate the lengthwise body shape of our MSCR. The performance of this closed-loop approach is compared with an open loop counterpart, which fails in all but one navigation attempts into the pancreatic duct
Improved receiver noise calibration for ADMX axion search: 4.54 to 5.41 μeV
Get PDFAxions are a well-motivated candidate for dark matter. The preeminent method to search for axion dark matter is known as the axion haloscope, which makes use of the conversion of axions to photons in a large magnetic field. Because of the weak coupling of axions to photons, however, the expected signal strength is exceptionally small. To increase signal strength, many haloscopes make use of resonant enhancement and high gain amplifiers, while also taking measures to keep receiver noise as low as possible such as the use of dilution refrigerators and ultra-low-noise electronics. In this paper, we derive the theoretical noise model based on the sources of noise found within a typical axion haloscope receiver chain, using the Axion Dark Matter eXperiment (ADMX) as a case study. We present examples of different noise calibration measurements at 1280 MHz taken during ADMX’s most recent data-taking run. These new results shed light on a previously unidentified interaction between the cavity and Josephson Parametric Amplifier as well as provide a better understanding of the systematic uncertainty on the system noise temperature used in the axion search analysis for this data-taking run. Finally, the consistency between the measurements and the detailed model provide suggestions for future improvements within ADMX and other axion haloscopes to reach a lower noise temperature
Pharmacodynamic effects of early aspirin withdrawal after percutaneous coronary intervention in patients with atrial fibrillation treated with ticagrelor or prasugrel
Get PDFDual antithrombotic therapy (DAT) without aspirin reduces bleeding compared with triple antithrombotic therapy (TAT) in patients with atrial fibrillation who have undergone percutaneous coronary intervention, without apparently increasing ischemic events. A prospective pharmacodynamic study was performed to investigate the impact of aspirin on bleeding time, platelet function and fibrin clot analysis in this population. Patients receiving TAT (n = 16), comprising aspirin, ticagrelor/prasugrel and a direct-acting oral anticoagulant (DOAC), were compared with those receiving DAT without aspirin (n = 18). Bleeding time was reduced with DAT compared with TAT (median 27.8 vs 30.0 minutes, p = .005). Assessed by light transmission aggregometry, median platelet aggregation was significantly increased with DAT compared with TAT in response to arachidonic acid (63 vs 3%, p = .002) and collagen (72 vs 37%, p p = .966) or thrombin-receptor-activating peptide (37 vs 24%, p = .086). VerifyNow P2Y12 assay showed > 70% inhibition in all patients. Fibrin clot lysis time and maximum turbidity were similar between groups. Using P2Y12 inhibitors of consistent potency, DAT improves hemostasis through sparing cyclooxygenase-1-mediated platelet activation but has a comparable effect to TAT on other pathways and fibrin clot properties. DAT with ticagrelor/prasugrel and DOAC may provide sufficient antithrombotic effect without excessive anti-hemostatic effect
The spiritual needs and care of children and young people with life-threatening or life-shortening conditions, and parents (SPARK):a mixed-method investigation
Get PDFPolarity from the Bottom Up: A Computational Framework for Predicting Spontaneous Polar Order
Get PDFSo-called polar liquid crystals possess spontaneous long-range mutual orientation of their electric dipole moments, conferring bulk polarity to fluid phases of matter. The combination of polarity and fluidity leads to complex phase behaviour, and rich new physics, yet the limited understanding around how specific molecular features generate long-range polar ordering in a fluid is a hindrance to development of new materials. In this work, we introduce a computational framework that probes the bimolecular potential energy landscape of candidate molecules, enabling us to dissect the role of directional intermolecular interactions in establishing polar order. In closely related families of materials we find conflicting preferences for (anti)parallel ordering which can be accounted for by specific interactions between molecules. Thus, our results allow us to argue that the presence (or absence) of polar order is a product of specific molecular features and strong directional intermolecular interactions rather than being simply a product of dipole-dipole forces. The design principles established can be leveraged to developing new polar liquid crystalline materials
A key role for hepatitis C virus NS5A serine 225 phosphorylation revealed by super-resolution microscopy
Get PDFNS5A is a multi-functional phosphoprotein that plays a key role in hepatitis C virus (HCV) genome replication and assembly. The consequences of NS5A phosphorylation for HCV biology remain largely undefined. We previously identified serine 225 (S225) as a major phosphorylation site within the low complexity sequence 1 (LCSI) of NS5A and used a phosphoablatant mutant (S225A) to define the role of this phosphorylation event in genome replication, NS5A-host interactions and sub-cellular localisation. In this study, we investigate this further by raising an antiserum to S225 phosphorylated NS5A (pS225). Western blot analysis revealed that pS225 was predominantly in the hyper-phosphorylated NS5A species. Using a panel of phosphoablatant mutants of other phosphorylation sites in LCSI, we obtained evidence that is consistent with bidirectional hierarchical phosphorylation initiated by phosphorylation at S225. Using super-resolution microscopy (Airyscan and Expansion), we revealed a unique architecture of NS5A-positive punctae in HCV-infected cells; pS225 was present on the surface of these punctae, close to lipid droplets. Although S225 phosphorylation was not specifically affected by treatment with the NS5A-targeting direct acting antiviral agent daclatasvir, this resulted in the condensation of NS5A-positive punctae into larger structures, recapitulating the S225A phenotype. These data are consistent with a key role for S225 phosphorylation in the regulation of NS5A function
Clinical significance of skeletal fat‐to‐muscle ratio in idiopathic hyperaldosteronism
Get PDFObjective
The objective of this study is to evaluate the correlation between the fat-to-muscle ratio (FMR) and insulin resistance (IR) with aldosterone production among patients with idiopathic hyperaldosteronism (IHA).
Methods
Patients with primary aldosteronism were screened from those with secondary hypertension and then subtyped via adrenal venous sampling. A total of 199 patients with IHA and 186 with essential hypertension (EH) (controls) were studied. Baseline clinical characteristics, including data on diabetes and IHA, were collected. The FMR was evaluated based on the distribution of adipose tissue and muscle, measured by a body composition analyzer.
Results
The prevalence of diabetes and prediabetes was significantly higher in patients with IHA compared to those with essential hypertension. IHA patients also had significantly higher hemoglobin A1c(HbA1c) levels, homeostatic model assessment of insulin resistance (HOMA-IR), and much lower quantitative insulin sensitivity check index scores than the EH group. FMR was positively associated with fasting insulin, HOMA-IR, aldosterone-to-renin ratio (ARR), and age. A higher FMR was linked to the prevalence of IHA, with a stepwise increase in risk observed from the lowest to the highest quartiles of FMR. Logistic regression analysis showed that both HOMA-IR and body mass index contributed to the elevated FMR. IHA may result from a substantial loss of muscle mass accompanied by fat accumulation.
Discussion
In this retrospective study, our findings suggest that FMR could serve as a valuable metric for early intervention and comanagement strategies in patients at risk of sarcopenic obesity. This approach could help block the progression from aldosterone-producing cell clusters to IHA, potentially inhibiting aldosterone overproduction in such patients
Development and validation of an artificial intelligence-based pipeline for predicting oral epithelial dysplasia malignant transformation
Get PDFBackground
Oral epithelial dysplasia (OED) is a potentially malignant histopathological diagnosis given to lesions of the oral cavity that are at risk of progression to malignancy. Manual grading of OED is subject to substantial variability and does not reliably predict prognosis, potentially resulting in sub-optimal treatment decisions.
Method
We developed a Transformer-based artificial intelligence (AI) pipeline for the prediction of malignant transformation from whole-slide images (WSIs) of Haematoxylin and Eosin (H&E) stained OED tissue slides, named ODYN (Oral Dysplasia Network). ODYN can simultaneously classify OED and assign a predictive score (ODYN-score) to quantify the risk of malignant transformation. The model was trained on a large cohort using three different scanners (Sheffield, 358 OED WSIs, 105 control WSIs) and externally validated on cases from three independent centres (Birmingham and Belfast, UK, and Piracicaba, Brazil; 108 OED WSIs).
Results
Model testing yielded an F1-score of 0.96 for classification of dysplastic vs non-dysplastic slides, and an AUROC of 0.73 for malignancy prediction, gaining comparable results to clinical grading systems.
Conclusions
With further large-scale prospective validation, ODYN promises to offer an objective and reliable solution for assessing OED cases, ultimately improving early detection and treatment of oral cancer
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