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This study introduces a novel approach for fabricating vertically stacked mini-LED arrays, integrating InGaN yellow and blue epitaxial layers with a stress buffer layer to enhance optoelectronic characteristics and structural stability. This method significantly simplifies the LED design by reducing the need for RGB configurations, thus lowering costs and system complexity. Employing vertical stacking integration technology, the design achieves high-density, efficient white light production suitable for multifunctional applications, including automotive lighting and outdoor signage. Experimental results demonstrate the exceptional performance of the stacked yellow and blue mini-LEDs in terms of luminous efficiency, wavelength precision, and thermal stability. The study also explores the performance of these LEDs under varying temperature conditions and their long-term reliability, indicating that InGaN-based yellow LEDs offer superior performance over traditional AlGaInP yellow LEDs, particularly in high-temperature environments. This technology promises significant advancements in the design and application of lighting systems, with potential implications for both automotive and general illumination markets. [ABSTRACT FROM AUTHOR]

Micro-LEDs have found widespread applications in modular large-screen TVs, automotive displays, and high-resolution-density augmented reality glasses. However, these micron-sized LEDs experience a significant efficiency reduction due to the defects originating from the dry etching process. By controlling the current distribution via engineering the electrode size, electrons will be less concentrated in the defect region. In this work, we propose a blue InGaN/GaN compound parabolic concentrator micro-LED with a metallic sidewall to boost efficiency by combining both an optical dipole cloud model and electrical TCAD (Technology Computer-Aided Design) model. By merely modifying the p-GaN contact size, the external quantum efficiency (EQE) can be improved by 15.6%. By further optimizing the passivation layer thickness, the EQE can be boosted by 52.1%, which helps enhance the display brightness or lower power consumption. [ABSTRACT FROM AUTHOR]

The negative stiffness bistable damper (NSBD) was proposed to suppress structural dynamic responses in our previous study. The vibration mitigation performance of the NSBD is influenced by its design parameters, including negative stiffness, cubic stiffness, and damping coefficients. However, it is extremely challenging to directly acquire the ideal design parameters of the NSBD owing to its inherent nonlinearity. To address this disadvantage, the optimal design approach for the NSBD, based on the equivalent linearization method (ELM) and genetic algorithm (GA), is presented in this paper. The nonlinear NSBD system can be transformed to a linear system utilizing the ELM based on the pseudo-excitation method (PEM). The linearization model that corresponds to the nonlinear NSBD is fairly accurate in its approximation and can be indicated from the numerical results. Then, the main structure's peak response is minimized through the optimization of the design parameters of the NSBD using the H∞ norm and GA. Moreover, the proposed approach's effectiveness is assessed using the optimal parameters to calculate the displacement responses of a tall building equipped with the NSBD during various seismic excitations. As revealed by the numerical results, the displacement of the tall building can be effectively restrained by the optimized NSBD. [ABSTRACT FROM AUTHOR]

Due to its very desirable properties, Chebyshev polynomials are often used in the design of public key cryptographic systems. This paper discretizes the Chebyshev mapping, generalizes the properties of Chebyshev polynomials, and proposes an improved public key encryption algorithm based on Chebyshev chaotic mapping and RSA, i.e., C R P K C − K i . This algorithm introduces alternative multiplication coefficients K i , the selection of which is determined by the size of T r T d x m o d   N = T d T r x m o d   N , and the specific value selection rules are shared secrets among participants, overcoming the shortcomings of previous schemes. In the key generation and encryption/decryption stages, more complex intermediate processes are used to achieve higher algorithm complexity, making the algorithm more robust against ordinary attacks. The algorithm is also compared with other RSA-based algorithms to demonstrate its effectiveness in terms of performance and security. [ABSTRACT FROM AUTHOR]

We propose a highly polarized vertical-cavity surface-emitting laser (VCSEL) consisting of staggered InGaN multiple quantum wells (MQWs), with the resonance cavity and polarization enabled by a bottom nanoporous (NP) n-GaN distributed Bragg reflectors (DBRs), and top TiO2 high-index contrast gratings (HCGs). Optoelectronic simulations of the 612 nm VCSEL were systematically and numerically investigated. First, we investigated the influences of the NP DBR and HCG geometries on the optical reflectivity. Our results indicate that when there are more than 17 pairs of NP GaN DBRs with 60% air voids, the reflectance can be higher than 99.7%. Furthermore, the zeroth-order reflectivity decreases rapidly when the HCG's period exceeds 518 nm. The optimal ratios of width-to-period (52.86 ± 1.5%) and height-to-period (35.35 ± 0.14%) were identified. The staggered MQW design also resulted in a relatively small blue shift of 5.44 nm in the emission wavelength under a high driving current. Lastly, we investigated the cavity mode wavelength and optical threshold gain of the VCSEL with a finite size of HCG. A large threshold gain difference of approximately 67.4–74% between the 0th and 1st order transverse modes can be obtained. The simulation results in this work provide a guideline for designing red VCSELs with high brightness and efficiency. [ABSTRACT FROM AUTHOR]

Simple Summary: Although quality of life (QOL) improves over time for most breast cancer survivors (BCSs), specific subgroup of BCSs may show persistently low or deteriorated QOL even after their treatment ends. Early identification of high-risk groups for QOL deterioration is crucial for quality cancer care. This study was conducted to identify subgroups of QOL change among 101 Korean BCSs, and to examine factors associated with subgroups that show poor QOL. During a 3-year observation, 22.6% of the participants showed consistently low or deteriorated QOL. Persistent symptoms of insomnia, fatigue, anxiety, depression, and comorbidity were found to be significant risk factors of poor QOL in BCS. These findings are helpful to identify high-risk groups for QOL deterioration among BCSs. The purpose of this study was to identify subgroups of quality of life (QOL) changes in breast cancer survivors (BCSs), and to determine factors associated with subgroups of consistently low or deteriorated QOL. We enrolled 101 women recently diagnosed with breast cancer in South Korea and asked them to complete a questionnaire at baseline (within 1 month of diagnosis), 1 year later (Year 1), 2 years later (Year 2), and 3 years later (Year 3). We assessed QOL using the global QOL subscale from the EORTC QLQ-C30. We defined low QOL as a global QOL score 10 points below the mean score of the general population. Based on low QOL as defined in this study, we identified subgroups of QOL changes over 3 years. We identified four subgroups of QOL changes: improved (47.4%), stable (30%), continuously low (8.8%), and deteriorated (13.8%), and considered the last two categories (22.6%) poor QOL. Logistic regression analyses demonstrated that significant determinants of poor QOL were insomnia at Year 1, fatigue and anxiety at Year 2, and fatigue, depression, and comorbidity at Year 3. In conclusion, persistent symptoms of insomnia, fatigue, anxiety, depression, and comorbidity are potential risk factors for poor QOL in BCSs. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) have emerged as a promising technology for various applications owing to their advantages, including low-cost fabrication, flexibility, and compatibility. However, a limited lifetime hinders the practical application of OLEDs in electronic devices. OLEDs are prone to degradation effects during operation, resulting in a decrease in device lifetime and performance. This review article aims to provide an exciting overview of OLED degradation effects, highlighting the various degradation mechanisms. Subsequently, an in-depth exploration of OLEDs degradation mechanisms and failure modes is presented. Internal and external processes of degradation, as well as the reactions and impacts of some compounds on OLED performance, are then elucidated. To overcome degradation challenges, the review emphasizes the importance of utilizing state-of-the-art analytical techniques and the role of these techniques in enhancing the performance and reliability of OLEDs. Furthermore, the review addresses the critical challenges of lifetime and device stability, which are crucial for the commercialization of OLEDs. This study also explores strategies to improve OLEDs' lifetime and stability, such as using barrier layers and encapsulation techniques. Overall, this article aims to contribute to the advancement of OLED technology and its successful integration into diverse electronic applications. [ABSTRACT FROM AUTHOR]

This study presents a design methodology for Takagi‐Sugeno (T‐S) fuzzy models‐based secure communications in multiple time‐delay chaotic (MTDC) systems with Rivest cipher 4 (RC4) algorithm. The main advantage of the RC4 algorithm is that the key length does not affect the encryption and decryption speeds. To block a hacker from stealing a message, this study proposes increasing the complexity of an encrypted message (ciphertext) using a method of double encryption using the RC4 algorithm and chaotic masking. As a result, this more secure communications system can effectively defend the encrypted message (ciphertext). First, the RC4 algorithm and a key are used to encrypt the initial message (plaintext). To enhance security, the encrypted message (ciphertext) is then converted into an encrypted signal, which is a double encryption using chaotic masking. Additionally, an improved genetic algorithm (IGA) is adopted in this study, it can seek better feedback gains of fuzzy controllers to speed up the synchronization. In accordance with the IGA, a model‐based fuzzy controller is synthesized to exponentially stabilize the error systems so that the trajectories of the slave systems can approach those of the master systems. Finally, a numerical example with simulations is provided to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The emergence of the Internet of Things (IoT) technology has brought about tremendous possibilities, but at the same time, it has opened up new vulnerabilities and attack vectors that could compromise the confidentiality, integrity, and availability of connected systems. Developing a secure IoT ecosystem is a daunting challenge that requires a systematic and holistic approach to identify and mitigate potential security threats. Cybersecurity research considerations play a critical role in this regard, as they provide the foundation for designing and implementing security measures that can address emerging risks. To achieve a secure IoT ecosystem, scientists and engineers must first define rigorous security specifications that serve as the foundation for developing secure devices, chipsets, and networks. Developing such specifications requires an interdisciplinary approach that involves multiple stakeholders, including cybersecurity experts, network architects, system designers, and domain experts. The primary challenge in IoT security is ensuring the system can defend against both known and unknown attacks. To date, the IoT research community has identified several key security concerns related to the architecture of IoT systems. These concerns include issues related to connectivity, communication, and management protocols. This research paper provides an all-inclusive and lucid review of the current state of anomalies and security concepts related to the IoT. We classify and analyze prevalent security distresses regarding IoT's layered architecture, including connectivity, communication, and management protocols. We establish the foundation of IoT security by examining the current attacks, threats, and cutting-edge solutions. Furthermore, we set security goals that will serve as the benchmark for assessing whether a solution satisfies the specific IoT use cases. [ABSTRACT FROM AUTHOR]

Background: Growing evidence supports exercise for people with lung cancer. This overview aimed to summarise exercise intervention efficacy and safety across the care continuum. Methods: Eight databases (including Cochrane and Medline) were searched (inception—February 2022) for systematic reviews of RCTs/quasi-RCTs. Eligibility: population—adults with lung cancer; intervention: exercise (e.g., aerobic, resistance) +/− non-exercise (e.g., nutrition); comparator: usual care/non-exercise; primary outcomes: exercise capacity, physical function, health-related quality of life (HRQoL) and post-operative complications. Duplicate, independent title/abstract and full-text screening, data extraction and quality ratings (AMSTAR-2) were completed. Results: Thirty systematic reviews involving between 157 and 2109 participants (n = 6440 total) were included. Most reviews (n = 28) involved surgical participants. Twenty-five reviews performed meta-analyses. The review quality was commonly rated critically low (n = 22) or low (n = 7). Reviews commonly included combinations of aerobic, resistance and/or respiratory exercise interventions. Pre-operative meta-analyses demonstrated that exercise reduces post-operative complications (n = 4/7) and improves exercise capacity (n = 6/6), whilst HRQoL findings were non-significant (n = 3/3). Post-operative meta-analyses reported significant improvements in exercise capacity (n = 2/3) and muscle strength (n = 1/1) and non-significant HRQoL changes (n = 8/10). Interventions delivered to mixed surgical and non-surgical populations improved exercise capacity (n = 3/4), muscle strength (n = 2/2) and HRQoL (n = 3). Meta-analyses of interventions in non-surgical populations demonstrated inconsistent findings. Adverse event rates were low, however, few reviews reported on safety. Conclusions: A large body of evidence supports lung cancer exercise interventions to reduce complications and improve exercise capacity in pre- and post-operative populations. Additional higher-quality research is needed, particularly in the non-surgical population, including subgroup analyses of exercise type and setting. [ABSTRACT FROM AUTHOR]

The emotional consequences of a cancer diagnosis are well documented and range from emotional distress, defined as suffering associated with feelings such as shock, fear, and uncertainty, through to psychological distress that may manifest as depression, anxiety, feelings of hopelessness, or heightened risk of suicide. This study set out to explore the assumption that the provision of emotional care should be the platform upon which all other aspects of cancer care are delivered and, that without attention to emotional care, no other aspects of cancer care can be fully realized. Utilizing qualitative focus groups and in-depth interviews with 47 patients, carers, and health professionals, emotional care was shown to be (1) fundamental to the provision of comprehensive cancer care, (2) essential to easing the burden of a cancer diagnosis and demands of treatment, (3) everyone's business, and (4) a component of cancer care at any time and every time. Future studies are needed to test interventions to enhance provision of intentional, purposeful, and individualized emotional care to help patents achieve the best health outcomes possible. [ABSTRACT FROM AUTHOR]

This systematic review investigated the effects of exercise interventions combined with diet and/or dietary supplement interventions on anthropometry, body composition, metabolic biomarkers, physical function, healthy lifestyles, quality of life, psychosocial variables and fatigue for women with breast cancer. A systematic search was performed in the PubMed and Web of Science databases (from inception to 1 March 2022). A review was carried out following the Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) guidelines. The methodological quality and the risk of bias of the included studies was assessed with the Physiotherapy Evidence Database (PEDro) scale. A total of 13 randomised controlled trial studies were included, comprising 1569 breast cancer patients. The main finding of this systematic review is that groups performing interventions combining exercise plus diet show significant improvements in cardiorespiratory fitness, muscular strength, body composition, quality of life, fatigue, anxiety, depression and sleep compared to control groups. On the other hand, the use of interventions combining exercise plus supplementation does not result in an improvement compared to groups using exercise alone or supplementation alone. [ABSTRACT FROM AUTHOR]

The event‐triggered output feedback fault‐tolerant control problem is studied in this paper for interval type‐2 Takagi–Sugeno (IT2 T‐S) fuzzy large‐scale systems with time delays. First, a fuzzy state observer is designed to address the immeasurable states problem. Then, by introducing a discrete event‐triggered mechanism, an observer‐based event‐triggered fuzzy decentralized controller with dynamic parameters is synthesized in the presence of actuator faults based on the nonparallel distribution compensation (PDC) design principle. The sufficient conditions of asymptotic stability for the closed‐loop systems are derived by constructing an appropriate dynamic parameter based Lyapunov–Krasovskii functional candidate. Finally, a simulation example is provided to verify the feasibility of the developed fuzzy control method. [ABSTRACT FROM AUTHOR]

Teachers' workplace victimization is a serious and concerning problem known to have numerous negative occupational and health outcomes for teachers. Surprisingly, however, the scientific literature has broadly overlooked schools as settings in which serious workplace violence occurs, and it has failed to systematically explore the antecedents and consequences of workplace victimization for teachers. To fill this gap, this study examined the structures of associations of teachers' victimization via threats, verbal violence, and property violence with somatic and posttraumatic symptoms using structural equation modeling. The sample included 366 Arabic and Jewish teachers in Israel. The findings indicate that the teachers who reported victimization and symptoms experienced burnout, whereas the teachers who reported victimization and had no symptoms did not experience burnout. A significant relationship of teachers' personal and professional characteristics with victimization, symptoms, and burnout also emerged. These findings advance our theoretical understanding of the predictors and consequences of violence against teachers in schools. Useful practices to improve teachers' occupational and health outcomes are discussed. [ABSTRACT FROM AUTHOR]

Background: Cancer-related fatigue (CRF) is a common and burdensome symptom in cancer patients that is influenced by multiple factors. Identifying factors associated with CRF may help in developing tailored interventions for fatigue management. This study aimed to examine the correlates of CRF among colorectal cancer patients undergoing postoperative adjuvant therapy based on the theory of unpleasant symptoms. Methods: A cross-sectional study was implemented, and finally, a sample of 363 participants from one tertiary general hospital and one tertiary cancer hospital was purposively recruited. Data were collected using the general information questionnaire, cancer fatigue scale, the distress disclosure index, Herth hope index, and perceived social support scale. Univariate analysis and multiple linear regression analysis were performed to determine the correlates of CRF. Results: The mean score of CRF among colorectal cancer patients was 21.61 (SD = 6.16, 95% CI 20.98–22.25), and the fatigue degree rating was "moderate". The multiple linear regression model revealed that 49.1% of the variance in CRF was explained by hope, sleep disorder, internal family support, self-disclosure, pain, and time since operation. Conclusions: Our study identified several significant, modifiable factors (self-disclosure, hope, internal family support, pain, and sleep disorder) associated with CRF. Understanding these correlates and developing targeted psychosocial interventions may be associated with the improvement of CRF in patients with colorectal cancer. [ABSTRACT FROM AUTHOR]

In this paper, a novel image encryption algorithm is proposed based on hyperchaotic two-dimensional sin-fractional-cos-fractional (2D-SFCF), called sin-fractional-cos-fractional image-encryption (SFCF-IE). The 2D-SFCF is constructed from two one-dimensional cosine fractional (1-DCFs), and it has a more complex chaotic behavior with a larger parameter space than one-dimensional chaotic systems. Compared with the two-dimensional (2D) chaotic system, the 2D-SFCF has a simple structure, and the parameter space in the chaotic state is continuous, which is beneficial to generating the keystream in the cryptosystem. Therefore, in the novel image encryption algorithm, we use the 2D-SFCF to generate the keystream of the cryptosystem. The encryption algorithm is a process of scrambling and diffusion. Different from common diffusion methods, the diffusion starting position of the SFCF-IE is randomly generated, enhancing the algorithm's security. Simulation experiments show that the image encrypted by this algorithm has better distribution characteristics and can resist common attack methods. [ABSTRACT FROM AUTHOR]

A lightweight on-device liquid consumption estimation system involving an energy-aware machine learning algorithm is developed in this work. This system consists of two separate on-device neural network models that carry out liquid consumption estimation with the result of two tasks: the detection of sip from gestures with which the bottle is handled by its user and the detection of first sips after a bottle refill. This predictive volume estimation framework incorporates a self-correction mechanism that can minimize the error after each bottle fill-up cycle, which makes the system robust to errors from the sip classification module. In this paper, a detailed characterization of sip detection is performed to understand the accuracy-complexity tradeoffs by developing and implementing a variety of different ML models with varying complexities. The maximum energy consumed by the entire framework is around 119 mJ during a maximum computation time of 300 μ s . The energy consumption and computation times of the proposed framework is suitable for implementation in low-power embedded hardware that can be incorporated in consumer grade water bottles. [ABSTRACT FROM AUTHOR]

There has been increasing interest in fuzzy theory in recent years, yet there are many issues to be resolved, mainly on topics related to controller design, such as the field of robot, artificial intelligence, and nonlinear systems etc. This study focuses on the development of triangular fuzzy numbers, the revising of triangular fuzzy numbers, and the constructing of a half-circle fuzzy number (HCFN) model, which can be utilized to perform more plural operations. They are further transformed for trigonometric functions and polar coordinates. From HCFNs we can conceive cylindrical fuzzy numbers, which work better in algebraic operations. An example of fuzzy control is given in a simulation to show the applicability of the proposed HCFNs. [ABSTRACT FROM PUBLISHER]

Given that chemotherapy treatments are done mostly in an outpatient setting, patients with cancer must deal with treatment-related symptoms mainly at home. Evidence suggests that they often feel left alone or unprepared to do so. This qualitative study explores how patients deal with chemotherapy-related symptoms in their home, which factors and ideas influence their self-management and what role professional caregivers play. One-off, semi-structured interviews were held with 28 adult patients with cancer being treated with chemotherapy. Using a Grounded Theory approach, we cyclically collected and analysed data to come to a thorough understanding of the major conceptual themes and their interconnections. Dealing with chemotherapy-related symptoms involves a process of experiencing and learning how side effects unfold over time and how to deal with them. Patients express very personal symptom experiences and symptom-management styles, which are shaped by personal factors (e.g. coping with cancer and cancer treatment, perceived level of control) and environmental factors (e.g. professionals' attitude, information resources). Improving symptom self-management support requires active exploration of the personal symptom experience and symptom-management style. Professional care should be tailored to the patient's perspective and should address personal and environmental determinants of their behaviour. [ABSTRACT FROM AUTHOR]

This study presents a decentralised H ∞ filter design problem for non‐linear large‐scale systems that are represented based on the Takagi–Sugeno fuzzy model. To enhance the design flexibility of the fuzzy filter for non‐linear large‐scale systems, the imperfect premise matching problem is adopted in the filter design procedure. In the sense of fuzzy Lyapunov, sufficient conditions for both asymptotic stability of the error system and a prescribed level of the H ∞ norm are ensured to guarantee the H ∞ fuzzy filter performance. The sufficient conditions are formulated in terms of linear matrix inequalities, which can be solved efficiently using convex optimisation algorithms. Finally, simulation examples are provided to verify the feasibility of the proposed approach. [ABSTRACT FROM AUTHOR]

This study studies the H∞ fuzzy controller design problem for a non‐linear large‐scale system with non‐linear interconnections and disturbance. In the large‐scale system, each subsystem, excluding non‐linear interconnections and disturbance, is transformed into a Takagi‐Sugeno fuzzy system and the nonlinear interconnections of each subsystem must satisfy a norm inequality. The number of rules for the large‐scale system as a whole can be reduced through the use of the norm inequality because the interconnection terms do not need to be transformed into fuzzy rule sets and thus the controller synthesis will be much easier. On the other hand, the H∞ performance can be improved by adjusting the weighting value of the norm inequality. The main theorems of this paper are obtained through the use of S ‐procedure and linear matrix inequality method. Lastly, the authors provide three examples to show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper considers the modeling of a tension leg platform (TLP) system. First, some mathematical formulations for tension leg platform systems are reviewed. Then, the neural network (NN) model is employed to represent a TLP system, which is done via the backpropagation algorithm. Meanwhile, a linear differential inclusion (LDI) state-space representation is constructed for the dynamics of the NN model. The LDI equation is similar to a T-S fuzzy system but makes it easier to analyze the stability of controlled systems. A parallel distributed compensation scheme, combined with H∞ control design is proposed to achieve control performance and to ensure the stability of TLP systems subjected to an external wave force. In terms of the stability analysis, the linear matrix inequality conditions guaranteeing the stability of the TLP system are derived from fuzzy Lyapunov theory. [ABSTRACT FROM PUBLISHER]

In this study we present a fuzzy robust control design which combines H control performance with Tagagi-Sugeno (T-S) fuzzy control for the control of delayed nonlinear structural systems under external excitations. We design a nonlinear fuzzy controller based on parallel distributed compensation schemes. The controller design problem is reformulated as a linear matrix inequality (LMI) problem as derived from the Lyapunov theory. This robust method is designed to overcome the modeling error that can occur between delayed nonlinear structural systems with T-S fuzzy models. Given the fuzzy-model-based H control and the stability conditions, the stability of a delayed nonlinear structural system under external excitation is ensured. Furthermore, the delayed nonlinear structural system is equipped with a tuned mass damper designed according to the first mode of frequency. The feedback gain of the fuzzy controller is found via the Matlab LMI toolbox. The proposed method is then applied to a delayed nonlinearly tuned mass damper system. The simulation results show that not only is the proposed method able to stabilize delayed nonlinear structural systems, but also has strong robustness in terms of preventing modeling errors and external excitations. [ABSTRACT FROM AUTHOR]

Survival analysis of the Cancer Genome Atlas (TCGA) dataset is a well-known method for discovering gene expression-based prognostic biomarkers of head and neck squamous cell carcinoma (HNSCC). A cutoff point is usually used in survival analysis for patient dichotomization when using continuous gene expression values. There is some optimization software for cutoff determination. However, the software's predetermined cutoffs are usually set at the medians or quantiles of gene expression values. There are also few clinicopathological features available in pre-processed datasets. We applied an in-house workflow, including data retrieving and pre-processing, feature selection, sliding-window cutoff selection, Kaplan–Meier survival analysis, and Cox proportional hazard modeling for biomarker discovery. In our approach for the TCGA HNSCC cohort, we scanned human protein-coding genes to find optimal cutoff values. After adjustments with confounders, clinical tumor stage and surgical margin involvement were found to be independent risk factors for prognosis. According to the results tables that show hazard ratios with Bonferroni-adjusted p values under the optimal cutoff, three biomarker candidates, CAMK2N1, CALML5, and FCGBP, are significantly associated with overall survival. We validated this discovery by using the another independent HNSCC dataset (GSE65858). Thus, we suggest that transcriptomic analysis could help with biomarker discovery. Moreover, the robustness of the biomarkers we identified should be ensured through several additional tests with independent datasets. [ABSTRACT FROM AUTHOR]

Despite the importance of maintaining an adequate hydration status, water intake is frequently neglected due to the fast pace of people's lives. For the elderly, poor water intake can be even more concerning, not only due to the damaging impact of dehydration, but also since seniors' hydration regulation mechanisms tend to be less efficient. This work focuses on the recognition of the pre-drinking hand-to-mouth movement (a drink trigger) with two main objectives: predict the occurrence of drinking events in real-time and free-living conditions, and assess the potential of using this method to trigger an external component for estimating the amount of fluid intake. This shall contribute towards the efficiency of more robust multimodal approaches addressing the problem of water intake monitoring. The system, based on a single inertial measurement unit placed on the forearm, is unobtrusive, user-independent, and lightweight enough for real-time mobile processing. Drinking events outside meal periods were detected with an F-score of 97% in an offline validation with data from 12 users, and 85% in a real-time free-living validation with five other subjects, using a random forest classifier. Our results also reveal that the algorithm first detects the hand-to-mouth movement 0.70 s before the occurrence of the actual sip of the drink, proving that this approach can have further applications and enable more robust and complete fluid intake monitoring solutions. [ABSTRACT FROM AUTHOR]