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BackgroundAt present, there is an increased demand for accurate and personalized patient monitoring because of the various challenges facing health care systems. For instance, rising costs and lack of physicians are two serious problems affecting the patient’s care. Nonintrusive monitoring of vital signs is a potential solution to close current gaps in patient monitoring. As an example, bed-embedded ballistocardiogram (BCG) sensors can help physicians identify cardiac arrhythmia and obstructive sleep apnea (OSA) nonintrusively without interfering with the patient’s everyday activities. Detecting OSA using BCG sensors is gaining popularity among researchers because of its simple installation and accessibility, that is, their nonwearable nature. In the field of nonintrusive vital sign monitoring, a microbend fiber optic sensor (MFOS), among other sensors, has proven to be suitable. Nevertheless, few studies have examined apnea detection. ObjectiveThis study aims to assess the capabilities of an MFOS for nonintrusive vital signs and sleep apnea detection during an in-lab sleep study. Data were collected from patients with sleep apnea in the sleep laboratory at Khoo Teck Puat Hospital. MethodsIn total, 10 participants underwent full polysomnography (PSG), and the MFOS was placed under the patient’s mattress for BCG data collection. The apneic event detection algorithm was evaluated against the manually scored events obtained from the PSG study on a minute-by-minute basis. Furthermore, normalized mean absolute error (NMAE), normalized root mean square error (NRMSE), and mean absolute percentage error (MAPE) were employed to evaluate the sensor capabilities for vital sign detection, comprising heart rate (HR) and respiratory rate (RR). Vital signs were evaluated based on a 30-second time window, with an overlap of 15 seconds. In this study, electrocardiogram and thoracic effort signals were used as references to estimate the performance of the proposed vital sign detection algorithms. ResultsFor the 10 patients recruited for the study, the proposed system achieved reasonable results compared with PSG for sleep apnea detection, such as an accuracy of 49.96% (SD 6.39), a sensitivity of 57.07% (SD 12.63), and a specificity of 45.26% (SD 9.51). In addition, the system achieved close results for HR and RR estimation, such as an NMAE of 5.42% (SD 0.57), an NRMSE of 6.54% (SD 0.56), and an MAPE of 5.41% (SD 0.58) for HR, whereas an NMAE of 11.42% (SD 2.62), an NRMSE of 13.85% (SD 2.78), and an MAPE of 11.60% (SD 2.84) for RR. ConclusionsOverall, the recommended system produced reasonably good results for apneic event detection, considering the fact that we are using a single-channel BCG sensor. Conversely, satisfactory results were obtained for vital sign detection when compared with the PSG outcomes. These results provide preliminary support for the potential use of the MFOS for sleep apnea detection.

Abstract The study proposes a novel model for DNA sequence classification that combines machine learning methods and a pattern-matching algorithm. This model aims to effectively categorize DNA sequences based on their features and enhance the accuracy and efficiency of DNA sequence classification. The performance of the proposed model is evaluated using various machine learning algorithms, and the results indicate that the SVM linear classifier achieves the highest accuracy and F1 score among the tested algorithms. This finding suggests that the proposed model can provide better overall performance than other algorithms in DNA sequence classification. In addition, the proposed model is compared to two suggested algorithms, namely FLPM and PAPM, and the results show that the proposed model outperforms these algorithms in terms of accuracy and efficiency. The study further explores the impact of pattern length on the accuracy and time complexity of each algorithm. The results show that as the pattern length increases, the execution time of each algorithm varies. For a pattern length of 5, SVM Linear and EFLPM have the lowest execution time of 0.0035 s. However, at a pattern length of 25, SVM Linear has the lowest execution time of 0.0012 s. The experimental results of the proposed model show that SVM Linear has the highest accuracy and F1 score among the tested algorithms. SVM Linear achieved an accuracy of 0.963 and an F1 score of 0.97, indicating that it can provide the best overall performance in DNA sequence classification. Naive Bayes also performs well with an accuracy of 0.838 and an F1 score of 0.94. The proposed model offers a valuable contribution to the field of DNA sequence analysis by providing a novel approach to pre-processing and feature extraction. The model’s potential applications include drug discovery, personalized medicine, and disease diagnosis. The study’s findings highlight the importance of considering the impact of pattern length on the accuracy and time complexity of DNA sequence classification algorithms.

Background: The term inflammatory bowel disease (IBD) describes disorders in which the intestines be inflamed. It has often been thought that they are due to an autoimmune disease. Two major types of IBD are ulcerative colitis (UC) and Crohn's disease (CD). UC is limited to the colon. CD can involve every part of the gastrointestinal tract from the mouth to the anus. Objective: To compare between serum and faecal calprotectin regarding their role in follow up of disease activity in inflammatory bowel disease patients. Patients and Methods: An observational cross-sectional study was conducted on 25 patients admitted to Tropical medicine department, Ain Shams University Hospitals. Results: Calprotectin is highly resistant to proteolysis and can hold in the stool sample for up to 7 days at room temperature. Higher levels of serum calprotectin were linked to a severe inflammatory state in the colon as well as significant clinical symptoms in UC patients. Also, serum calprotectin, CRP, and ESR levels were compared to IBD activity and it was detected that serum calprotectin levels had more sensitivity and specificity than CRP and ESR in identifying IBD activity. Serum calpro-tectin levels in patients with IBD activity either UC or CD groups, were considerably more than in remission. SC and FC levels were higher levels in clinically active IBD comparing with inactive IBD. Conclusion: Serum calprotectin levels are higher in patients with IBD and are related to clinical activity. High serum calprotectin levels can distinguish between patients who are clinically active and those who are in remission in both UC and CD groups. Our findings show that serum calprotectin may be a promising simple diagnostic and prognostic biomarker for IBD however more research is needed to reach a judgment in this regard. [ABSTRACT FROM AUTHOR]

As a multitargeted kinase inhibitor, sunitinib has carved its way into demonstrating itself as a most effective tyrosine kinase inhibitor in the treatment of metastatic renal cell carcinoma. Mechanistically, sunitinib inhibits multiple receptor tyrosine kinases, especially those involved in angiogenesis, that is, vascular endothelial growth factor receptor, plateletderived growth factor receptor, and proto-oncogene cKIT. Sunitinib has also been implicated in enhancing cancer invasiveness and metastasis. Mechanisms of resistance are poorly understood, but both intrinsic and acquired mechanisms are thought to be involved. While the side effects are manageable, sunitinib, like many other tyrosine kinase inhibitors, can be associated with serious toxicities that require careful management including frequent dose reductions. Although still in the early stage, emerging evidence points to an immunomodulatory role for sunitinib. It is also likely to contribute to the overall outcomes, especially those seen in metastatic renal cell carcinoma, and such effects are thought to be mediated by the proto-oncogene cKIT receptor. Combination with other modalities such as stereotactic body radiation therapy, therapeutic vaccines, and checkpoint inhibitors is being pursued for improved efficacy. [ABSTRACT FROM AUTHOR]

A maximum principle is derived for the optimal control of a beam with Kelvin–Voigt damping subject to an external excitation with the control exercised by means of piezoelectric patch actuators. The objective functional is defined as a weighted quadratic functional of the displacement and velocity which is to be minimized at a given terminal time. A penalty term is also part of the objective functional defined as the control voltage used in the control process. The maximum principle makes use of a Hamiltonian defined in terms of an adjoint variable and the control function. The optimal control problem is expressed as a coupled system of partial differential equations in terms of state, adjoint and control variables subject to boundary, initial and terminal conditions. The solution is obtained by expanding the state and adjoint variables in terms of eigenfunctions and determining the optimal control using the maximum principle. Numerical examples are given to demonstrate the applicability and the efficiency of the proposed method. [ABSTRACT FROM PUBLISHER]

Time delays exist in active control systems. Although a time delay in most cases is small, it results in the actuator applying energy to the control system with a time delay. This might cause instability of the dynamic systems and degrade the performance of the control systems. The objective of the present work is to propose a feasible methodology that can achieve good control performance for a dynamic beam structure system by time-delayed boundary torque actuators. The control problem is to determine optimal time-delayed boundary control by minimizing a given performance criterion. The performance criterion is specified as a weighted quadratic functional of the dynamic responses of the beam which is to be minimized at a specified terminal time using continuous time-delayed torque actuators. The modal expansion approach is used to convert the optimal control problem of a distributed parameter system into the optimal control problem of a linear lumped parameter system (LPS). A direct state-control parameterization approach is proposed where wavelets are employed to solve time-delayed LPS. The operational matrices of integration and delay are utilized to reduce the solution of linear time-varying delayed systems to the solution of algebraic equations. A numerical simulation is presented to illustrate the efficiency of the proposed control algorithm. [ABSTRACT FROM PUBLISHER]

Significance: The scattering and polarization characteristics of various organs of in vivo wildtype zebrafish in three development stages were investigated using a non-destructive and label-free approach. The presented results showed a promising first step for the usability of Jones-matrix optical coherence tomography (JM-OCT) in zebrafish-based research. Aim: We aim to visualize and quantify the scatter and polarization signatures of various zebrafish organs for larvae, juvenile, and young adult animals in vivo in a non-invasive and label-free way. Approach: A custom-built polarization-sensitive JM-OCT setup in combination with a motorized translation stage was utilized to investigate live zebrafish. Depth-resolved scattering (intensity and attenuation coefficient) and polarization (birefringence and degree of polarization uniformity) properties were analyzed. OCT angiography (OCT-A) was utilized to investigate the vasculature label-free and non-destructively. Results: The scatter and polarization signatures of the zebrafish organs such as the eye, gills, and muscles were investigated. The attenuation coefficient and birefringence changes between 1- and 2-month-old animals were evaluated in selected organs. OCT-A revealed the vasculature of in vivo larvae and juvenile zebrafish in a label-free manner. Conclusions: JM-OCT offers a rapid, label-free, non-invasive, tissue specific, and three-dimensional imaging tool to investigate in vivo processes in zebrafish in various development stages. [ABSTRACT FROM AUTHOR]

A methodology is described for solving optimal pointwise control of a coupled system of Burgers' equations. It is aimed to determine the optimal pointwise control that minimizes a given performance measure. The performance measure is specified as a quadratic functional of the distance between a final state function and a predefined target function along with the energy due to the control effort. The modal expansion method is used to reduce the optimal control of distributed parameter systems into the control of the invariant lumped parameter systems. A system of non-linear algebraic equations are derived as necessary conditions of optimality and solved by Runge–Kutta method to obtain the optimal Fourier coefficients and frequencies. The feasibility of the proposed methodology is demonstrated by numerical simulations. [ABSTRACT FROM PUBLISHER]

Abstract: Active control of a vibrating beam using piezoelectric patch actuators is considered. The specific structure to be studied is an Euler–Bernoulli beam with piezoelectric actuators bonded to the top and bottom surfaces of the beam. The equation of motion includes Heaviside functions and their derivatives due to finite size piezo patches which provide the control force to damp out vibrations. Optimal control theory is formulated with the objective function specified as a weighted quadratic functional of the dynamic responses of the beam which is to be minimized at a specified terminal time. The expenditure of the control forces is included in the objective function as a penalty term. The optimal control law is derived using a maximum principle developed by Sadek et al. . The maximum principle involves a Hamiltonian expressed in terms of an adjoint variable with the state and adjoint variables linked by terminal conditions leading to a boundary-initial-terminal value problem. The explicit solution of the problem is developed using eigenfunction expansions of the state and adjoint variables. The numerical results are given to assess the effectiveness and the capabilities of piezo actuation to damp out the vibrations. [Copyright &y& Elsevier]