Clinical evaluation of stretchable and wearable inkjet-printed strain gauge sensor for respiratory rate monitoring at different body postures

Respiratory rate (RR) is a vital sign with continuous, convenient, and accurate measurement which is difficult and still under investigation. The present study investigates and evaluates a stretchable and wearable inkjet-printed strain gauge sensor (IJP) to estimate the RR continuously by detecting the respiratory volume change in the chest area. As the volume change could cause different strain changes at different body postures, this study aims to investigate the accuracy of the IJP RR sensor at selected postures. The evaluation was performed twice on 15 healthy male subjects (mean ± SD of age: 24 ± 1.22 years). The RR was simultaneously measured in breaths per minute (BPM) by the IJP RR sensor and a reference RR sensor (e-Health nasal thermal sensor) at each of the five body postures namely standing, sitting at 90°, Flower’s position at 45°, supine, and right lateral recumbent. There was no significant difference in measured RR between IJP and reference sensors, between two trials, or between different body postures (all p \u3e 0.05). Body posture did not have any significant effect on the difference of RR measurements between IJP and the reference sensors (difference \u3c 0.01 BPM for each measurement in both trials). The IJP sensor could accurately measure the RR at different body postures, which makes it a promising, simple, and user-friendly option for clinical and daily uses

Sleep apnea syndrome sensing at C-Band

A non-intrusive sleep apnea detection system using a C-Band channel sensing technique is proposed to monitor sleep apnea syndrome in real time. The system utilizes perturbations of RF signals to differentiate between patient's breathing under normal and sleep apnea conditions. The peak distance calculation is used to obtain the respiratory rates. A comparison of the datasets generated by the proposed method and a wearable sensor is made using a concordance correlation coefficient to establish its accuracy. The results show that the proposed sensing technique exhibits high accuracy and robustness, with more than 80% concordance with the wearable breathing sensor. This method is, therefore, a good candidate for the real-time wireless detection of sleep apnea

Comparison of HRV Indices of ECG and BCG Signals

Electrocardiography (ECG) plays a significant role in diagnosing heart-related issues, it provides, accurate, fast, and dependable insights into crucial parameters like QRS complex duration, the R-R interval, and the occurrence, amplitude, and duration of P, R, and T waves. However, utilizing ECG for prolonged monitoring poses challenges as it necessitates connecting multiple electrodes to the patient's body. This can be discomforting and disruptive, hampering the attainment of uninterrupted recordings. Ballistocardiography (BCG) emerges as a promising substitute for ECG, presenting a non-invasive technique for recording the heart's mechanical activity. BCG signals can be captured using sensors positioned beneath the bed, thereby providing enhanced comfort and convenience for long-term monitoring of the subject. In a recent study, researchers compared the heart rate variability (HRV) indices derived from simultaneously acquired ECG and BCG signals. Encouragingly, the BCG signal yielded satisfactory results similar to those obtained from ECG, implying that BCG holds potential as a viable alternative for prolonged monitoring. The findings of this study carry substantial implications for the advancement of innovative, non-invasive methods in monitoring heart health. BCG showcases the ability to offer a more comfortable and convenient alternative to ECG while retaining its capacity to deliver accurate and reliable cardiac information concerning a patient's condition.Comment: 8 Pages, 6 Figures, International Journal of Modern Trends in Engineering and Researc

The light requirements for growth and photosynthesis in seagrasses with emphasis on Texas estuaries : a literature survey

During the last 20 years, seagrass communities throughout the world have experienced decreased productivity and distribution. These declines have often been attributed to decreased water transparency as a result of turbidity or shading by epiphytic algae. Epiphytic shading is often an indication of nutrient enrichment caused by anthropogenic inputs. Although both epiphytes and turbidity occur as natural phenomena, human activities can exacerbate existing natural conditions with adverse effects on seagrass communities. The objectives of this study were (a) to review the existing literature and data available on the effect of natural and anthropogenic factors on the underwater light environment; (b) to examine the relationship between light and seagrass distribution and productivity; and (c) to make recommendations on how to protect seagrass habitats in Texas bays and estuaries. To meet these goals, we have examined the available literature, emphasizing the physiological response of seagrasses to light and temperature. By using data and observations collected on a variety of species from around the world we may be better able to define the light requirements of Texas seagrasses. A knowledge of the minimum annual light requirements for seagrass growth is necessary to maintain the current distribution of Texas species. This information will also be required in the development of a management plan that permits the expansion and establishment of new seagrass habitat.Submitted to United States Environmental Protection Agency, Region 6 ... Dallas, Tx31 July 1993Marine Scienc

Ambient Intelligence in Healthcare: A State-of-the-Art

Information technology advancement leads to an innovative paradigm called Ambient Intelligence (AmI). A digital environment is employed along with AmI to enable individuals to be aware to their behaviors, needs, emotions and gestures. Several applications of the AmI systems in healthcare environment attract several researchers. AmI is considered one of the recent technologies that support hospitals, patients, and specialists for personal healthcare with the aid of artificial intelligence techniques and wireless sensor networks. The improvement in the wearable devices, mobile devices, embedded software and wireless technologies open the doors to advanced applications in the AmI paradigm. The WSN and the BAN collect medical data to be used for the progress of the intelligent systems adapted inevitably. The current study outlines the AmI role in healthcare concerning with its relational and technological nature. Health

Rehabilitation in scoliosis - an overview of the most important procedures

Introduction: Scoliosis is defined as deformation of the spine and torso in three dimensions. Study show that scoliosis affects 68% of healthy individuals over 65 years of age with no low back pain. The aim of this article is to review the available scoliosis rehabilitation methods, including the newest physical rehabilitation trends. Material and methods: Articles in the Google Scholar, Pub Med database have been analysed using keywords: scoliosis, deformation of the spine and torso, modern methods of rehabilitation, older people. Results: After skeletal maturity, curves less than 30°do not progress, however most curves greater than 50°continue to progress with approximate change of 1°per year. Bracing is one of the most popular options of scoliosis treatment. Braces usage aims to slow the progression of the curve. However, complications resulting from the physical changes caused by the compression of the body and/or psychological effects due to the disturbance of the appearance while wearing the brace may occure. The Lehnert-Schroth three-plane corrective breath method principles are: a proper breathing technique where the ribs are used as levers and the breath is directed to the unstretched parts of lungs allowing correction of the curvature of the spine, and secondly activation of non-working muscles on the side of the concave curvature. Nevertheless, surgical procedure is advised for curves greater than 45° in immature patients and greater than 50° in mature patients. Conclusions: Scoliosis, defined as spinal and torso deformity in three planes. 80% of all cases of this postural defect are juvenile idiopathic scoliosis (AIS). However, degenerative scoliosis developed during the patient’s life due to the degeneration of the discs of the spine is frequent in people over the age of 65. It often limits daily functioning and can cause severe pain that requires medical intervention. It has been proven that properly selected systematic rehabilitation may lead to significant improvement in the spinal alignment. Nevertheless, in severe cases surgical treatment may be necessary

Pyogenic spondylitis

Pyogenic spondylitis is a neurological and life threatening condition. It encompasses a broad range of clinical entities, including pyogenic spondylodiscitis, septic discitis, vertebral osteomyelitis, and epidural abscess. The incidence though low appears to be on the rise. The diagnosis is based on clinical, radiological, blood and tissue cultures and histopathological findings. Most of the cases can be treated non-operatively. Surgical treatment is required in 10–20% of patients. Anterior decompression, debridement and fusion are generally recommended and instrumentation is acceptable after good surgical debridement with postoperative antibiotic cover

Continuous assessment of epileptic seizures with wrist-worn biosensors

Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 145-159).Epilepsy is a neurological disorder characterized predominantly by an enduring predisposition to generate epileptic seizures. The apprehension about injury, or even death, resulting from a seizure often overshadows the lives of those unable to achieve complete seizure control. Moreover, the risk of sudden death in people with epilepsy is 24 times higher compared to the general population and the pathophysiology of sudden unexpected death in epilepsy (SUDEP) remains unclear. This thesis describes the development of a wearable electrodermal activity (EDA) and accelerometry (ACM) biosensor, and demonstrates its clinical utility in the assessment of epileptic seizures. The first section presents the development of a wrist-worn sensor that can provide comfortable and continuous measurements of EDA, a sensitive index of sympathetic activity, and ACM over extensive periods of time. The wearable biosensor achieved high correlations with a Food and Drug Administration (FDA) approved system for the measurement of EDA during various classic arousal experiments. This device offers the unprecedented ability to perform comfortable, long-term, and in situ assessment of EDA and ACM. The second section describes the autonomic alterations that accompany epileptic seizures uncovered using the wearable EDA biosensor and time-frequency mapping of heart rate variability. We observed that the post-ictal period was characterized by a surge in sympathetic sudomotor and cardiac activity coinciding with vagal withdrawal and impaired reactivation. The impact of autonomic dysregulation was more pronounced after generalized tonic-clonic seizures compared to complex partial seizures. Importantly, we found that the intensity of both sympathetic activation and parasympathetic suppression increased approximately linearly with duration of post-ictal EEG suppression, a possible marker for the risk of SUDEP. These results highlight a critical window of post-ictal autonomic dysregulation that may be relevant in the pathogenesis of SUDEP and hint at the possibility for assessment of SUDEP risk by autonomic biomarkers. Lastly, this thesis presents a novel algorithm for generalized tonic-clonic seizure detection with the use of EDA and ACM. The algorithm was tested on 4213 hours (176 days) of recordings from 80 patients containing a wide range of ordinary daily activities and detected 15/16 (94%) tonic-clonic seizures with a low rate of false alarms (<; 1 per 24 h). It is anticipated that the proposed wearable biosensor and seizure detection algorithm will provide an ambulatory seizure alarm and improve the quality of life of patients with uncontrolled tonic-clonic seizures.by Ming-Zher Poh.Ph.D

Material extrusion-based additive manufacturing: G-code and firmware attacks and Defense frameworks

Additive Manufacturing (AM) refers to a group of manufacturing processes that create physical objects by sequentially depositing thin layers. AM enables highly customized production with minimal material wastage, rapid and inexpensive prototyping, and the production of complex assemblies as single parts in smaller production facilities. These features make AM an essential component of Industry 4.0 or Smart Manufacturing. It is now used to print functional components for aircraft, rocket engines, automobiles, medical implants, and more. However, the increased popularity of AM also raises concerns about cybersecurity. Researchers have demonstrated strength degradation attacks on printed objects by injecting cavities in the design file which cause premature failure and catastrophic consequences such as failure of the attacked propeller of a drone during flight. Since a 3D printer is a cyber-physical system that connects the cyber and physical domains in a single process chain, it has a different set of vulnerabilities and security requirements compared to a conventional IT setup. My Ph.D. research focuses on the cybersecurity of one of the most popular AM processes, Material Extrusion or Fused Filament Fabrication (FFF). Although previous research has investigated attacks on printed objects by altering the design, these attacks often leave a larger footprint and are easier to detect. To address this limitation, I have focused on attacks at the intermediate stage of slicing through minimal manipulations at the individual sub-process level. By doing so, I have demonstrated that it is possible to implant subtle defects in printed parts that can evade detection schemes and bypass many quality assessment checks. In addition to exploring attacks through design files or network layer manipulations, I have also proposed firmware attacks that cause damage to the printed parts, the printer, and the printing facility. To detect sabotage attacks on FFF process, I have developed an attack detection framework that analyzes the cyber and physical domain state of the printing process and detects anomalies using a series of estimation and comparison algorithms in time, space, and frequency domains. An implementation case study confirms that cyber-physical security frameworks are an effective solution against sophisticated sabotage attacks. The increasing use of 3D printing technology to produce functional components underscores the growing importance of compliance and regulations in ensuring their quality and safety. Currently, there are no standards or best practices to guide a user in making a critical printing setup forensically ready. Therefore, I am proposing a novel forensic readiness framework for material extrusion-based 3D printing that will guide standards organizations in formulating compliance criteria for important 3D printing setups. I am optimistic that my offensive and defensive research endeavors presented in this thesis will serve as a valuable resource for researchers and industry practitioners in creating a safer and more secure future for additive manufacturing