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This work investigates the attack strategy design problem of the false data injection attack against the cyber-physical system. Distinct from the relevant results which utilise the current intercepted data or additionally consider side information, a more universal attack model is proposed which combines historical data and side information with the current intercepted data to synergistically deteriorate the system estimation performance. In order to quantify the impact resulting from the proposed attack strategy, the optimisation objective is characterised by deriving the error covariance matrix under the attacks, which becomes more intricate since the proposed attack model introduces more decision variables and coupled terms. Take the stealthiness which is characterised by Kullback-Leibler divergence as the constraints, the problem investigated in this work is equivalently transformed into the constrained multi-variable non-convex optimisation problems, which are not able to be solved directly by the methods in the relevant results. By utilising the Lagrange multiplier method, the structural characteristic of the optimal mean and the optimal covariance which only related to the Lagrange multiplier are derived, such that the optimal distribution of the modified innovation is able to be obtained by a simple search procedure. Following that, the design of the optimal attack strategy is completed by using semi-definite programming to derive the optimal attack matrices. Finally, the simulation examples are given such that the validity of the results is verified. [ABSTRACT FROM AUTHOR]

Catheter-based pulmonary artery denervation (PADN) has achieved promising outcomes to treat pulmonary hypertension (PH). We herein present stereotactic body radiotherapy (SBRT) as a novel noninvasive approach for PADN. A single fraction of 15 Gy, 20 Gy or 25 Gy was delivered for PADN in a thromboxane A2 (TxA2) - induced acute PH swine model. We demonstrated that PADN by 20-Gy SBRT reduced mean pulmonary artery (PA) pressure during the TxA2 challenge. All SBRT dosages led to a deeper denervation area compared with radiofrequency ablation (RFA) and reduced sympathetic neural norepinephrine synthesis in the ablation zone. Probable radiation related side effects were mostly found in animals treated with 25-Gy. In subsequent monocrotaline-induced chronic PH animals, PADN by 20-Gy SBRT resulted in more significant improvement in pulmonary hemodynamics and PA remodeling in comparison to RFA. In summary, our findings suggest that appropriate SBRT scheme could balance the efficacy and safety for PADN, potentiating to be a novel strategy to treat PH. Catheter-based pulmonary artery denervation (PADN) has achieved promising outcomes to treat pulmonary hypertension (PH). Here, the authors show stereotactic body radiotherapy is a novel noninvasive approach for PADN with improved pulmonary hemodynamics in both acute and chronic PH swine models. [ABSTRACT FROM AUTHOR]

Background: Systemic light chain amyloidosis is a rare and debilitating disease, especially for which initially presented with digestive tract involvement. Myocardial amyloidosis is highly aggressive with generally poor prognosis and often resulted in missed diagnosis or misdiagnosis with routine examination tools. Multimodality imaging play an important role in diagnosing the amyloidosis effect on multiple organs. Chemoradiotherapy is the mainstay of treatment. Case presentation: This article presents a rare case of systemic light chain amyloidosis, initially with gastrointestinal symptoms, in a 68-year-old male. He was hospitalized with diarrhea for one year and a half, dysphagia for 4 months, but he had no dyspnea. The transthoracic echocardiogram revealed myocardial hypertrophy of the left ventricle, the hypertrophic heart muscle echoed like "ground glass". The left ventricular ejection fraction (LVEF) detected by Simpson method was 51% and global longitudinal strain (GLS) was -9.00%. But cardiac magnetic resonance showed the patient without gadolinium delayed enhancement. The urinary protein series quantification and the serum free light chain levels were all increased. While the ratio of free κ and free λ was decreased. Hence, the abdominal fat biopsy of the patient was amyloidosis by electronic and immunoelectron microscopy. Organs involved include heart, kidneys, gastrointestinal tract and nervous system, stage III of mayo 2012 model. The patient was treated with Dara-BCD chemotherapy. This case underscores the diagnostic complexity, emphasizing the need for early identification given the grim prognosis associated with systemic AL amyloidosis requiring clinical data, detailed imaging, and histopathological insights. After discharge, the patient became better and followed up in the outpatient. Conclusions: Systemic light chain amyloidosis can easily be missed diagnosis or misdiagnosis in its early stages, losing the opportunity for initiating earlier treatments to improve potential patient outcomes. Despite advancements in diagnostic biomarkers, this case highlights the potential for missed diagnosis with standard CMR imaging when gadolinium enhancement is negative. The utility of echocardiographic features such as reduced GLS and abnormal ECG findings emerges as critical in early identification of myocardial amyloidosis. The correct diagnosis of this case relied on the comprehensive utilization of multimodal imaging techniques including biopsy. [ABSTRACT FROM AUTHOR]

The ECG diagnosis of LVH is predominantly based on the QRS voltage criteria. The classical paradigm postulates that the increased left ventricular mass generates a stronger electrical field, increasing the leftward and posterior QRS forces, reflected in the augmented QRS amplitude. However, the low sensitivity of voltage criteria has been repeatedly documented. We discuss possible reasons for this shortcoming and proposal of a new paradigm. The theoretical background for voltage measured at the body surface is defined by the solid angle theorem, which relates the measured voltage to spatial and non‐spatial determinants. The spatial determinants are represented by the extent of the activation front and the distance of the recording electrodes. The non‐spatial determinants comprise electrical characteristics of the myocardium, which are comparatively neglected in the interpretation of the QRS patterns. Various clinical conditions are associated with LVH. These conditions produce considerable diversity of electrical properties alterations thereby modifying the resultant QRS patterns. The spectrum of QRS patterns observed in LVH patients is quite broad, including also left axis deviation, left anterior fascicular block, incomplete and complete left bundle branch blocks, Q waves, and fragmented QRS. Importantly, the QRS complex can be within normal limits. The new paradigm stresses the electrophysiological background in interpreting QRS changes, i.e., the effect of the non‐spatial determinants. This postulates that the role of ECG is not to estimate LV size in LVH, but to understand and decode the underlying electrical processes, which are crucial in relation to cardiovascular risk assessment. [ABSTRACT FROM AUTHOR]