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1.
Article in English | MEDLINE | ID: mdl-38429594

ABSTRACT

The transition to sustainable energy is crucial for mitigating climate change impacts. This study addresses this imperative by simulating a green hydrogen supply chain tailored for residential cooking in Oman. The supply chain encompasses solar energy production, underground storage, pipeline transportation, and residential application, aiming to curtail greenhouse gas emissions and reduce the levelized cost of hydrogen (LCOH). The simulation results suggest leveraging a robust 7 GW solar plant. Oman achieves an impressive annual production of 9.78 TWh of green hydrogen, equivalent to 147,808 tonnes of H2, perfectly aligning with the ambitious goals of Oman Vision 2040. The overall LCOH for the green hydrogen supply chain is estimated at a highly competitive 6.826 USD/kg, demonstrating cost competitiveness when benchmarked against analogous studies. A sensitivity analysis highlights Oman's potential for cost-effective investments in green hydrogen infrastructure, propelling the nation towards a sustainable energy future. This study not only addresses the pressing issue of reducing carbon emissions in the residential sector but also serves as a model for other regions pursuing sustainable energy transitions. The developed simulation models are publicly accessible at https://hychain.co.uk , providing a valuable resource for further research and development in the field of green hydrogen supply chains.

2.
Article in English | MEDLINE | ID: mdl-38083061

ABSTRACT

Human Activity Recognition (HAR) is one of the important applications of digital health that helps to track fitness or to avoid sedentary behavior by monitoring daily activities. Due to the growing popularity of consumer wearable devices, smartwatches, and earbuds are being widely adopted for HAR applications. However, using just one of the devices may not be sufficient to track all activities properly. This paper proposes a multi-modal approach to HAR by using both buds and watch. Using a large dataset of 44 subjects collected from both in-lab and in-home environments, we demonstrate the limitations of using a single modality as well as the importance of a multi-modal approach. Moreover, we also train and evaluate the performance of five different machine learning classifiers for various combinations of devices such as buds only, watch only, and both. We believe the detailed analyses presented in this paper may serve as a benchmark for the research community to explore and build upon in the future.


Subject(s)
Human Activities , Wearable Electronic Devices , Humans , Machine Learning , Exercise
3.
Article in English | MEDLINE | ID: mdl-38083073

ABSTRACT

Activities of daily living is an important entity to monitor for promoting healthy lifestyle for chronic disease patients, children and the healthy population. This paper presents a smartwatch and earbuds inertial sensors based multi-modal power efficient end-to-end mobile system for continuous, passive and accurate detection of broad daily activity classes. We collected various posture, stationary and moving activity data from 40 diverse subjects using earbuds and smartwatch and develop the novel power optimized end-to-end operational system consisting of i) optimized device sampling rates and Bluetooth packet transfer rates, ii) data buffering mechanism, iii) background services, and iv) optimized model size, and demonstrating 93% macro recall score in detecting various activities. Our power optimized solution uses 80%, 40% and 33.33% less battery power for the smartphone, smartwatch, and earbuds respectively, compared to a power agnostic system with an estimated continuous no-charging run time of 50 hours, 16.67 hours, and 25 hours for the smartphone, smartwatch, and earbuds respectively.Clinical relevance- The end-to-end power optimized activity detection system presented in this paper will assist practicing clinicians toward treatment of various chronic disease patients (e.g. diabetes, hypertension, heart disease and obesity) by long-term, continuous monitoring of their lifestyle and sedentary behavior.


Subject(s)
Mobile Applications , Child , Humans , Activities of Daily Living , Smartphone , Chronic Disease , Electric Power Supplies
4.
Int Wound J ; 20(9): 3639-3647, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37259676

ABSTRACT

The characteristics of the pilonidal sinus that are associated with recurrence have scarcely been investigated in the literature. This study aims to evaluate the outcomes of patients with sacrococcygeal pilonidal sinus disease who were managed by a non-operative technique using Salih's preparation. This study also tries to classify the patients according to the features that determine the outcome of the intervention. This is a single-group cohort study that enrolled consecutive patients that had pilonidal sinus. All the patients were managed using Salih's preparation. The patients were seen at the clinic 6 weeks after the intervention to record data of recurrence. The Statistical Package for the Social Sciences (SPSS) Version 25 was used for coding and analysing the data. Test of significance and odds ratio were calculated for all of the features. The total number of patients receiving Salih's preparation was 12 123 cases, of which only 3529 patients were included in this study. The mean age of the participants was 26.95 years, ranging from 14 to 55 years. The most significant factor related to the recurrence was the presence of an abscess. After summation of all odd ratios, the percentage of each one from the total was calculated, and accordingly, the patients were divided into three classes. Non-operative methods using a preparation with antimicrobial and sclerosing properties can be an alternative for surgical intervention with a lower risk of recurrence. Classification of patients based on specific criteria can give clinicians and even patients themselves a vision of the chance of recurrence and treatment success.


Subject(s)
Pilonidal Sinus , Wound Healing , Humans , Adult , Pilonidal Sinus/surgery , Cohort Studies , Neoplasm Recurrence, Local , Sacrococcygeal Region/surgery , Treatment Outcome , Recurrence
5.
J Gastrointest Cancer ; 54(4): 1046-1057, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37247115

ABSTRACT

PURPOSE: Colorectal cancers are composed of heterogeneous cell populations in the concepts of genetic and functional degrees that among them cancer stem cells are identified with their self-renewal and stemness capability mediating primary tumorigenesis, metastasize, therapeutic resistance, and tumor recurrence. Therefore, understanding the key mechanisms of stemness in colorectal cancer stem cells (CRCSCs) provides opportunities to discover new treatments or improve existing therapeutic regimens. METHODS: We review the biological significance of stemness and the results of potential CRCSC-based targeted immunotherapies. Then, we pointed out the barriers to targeting CRCSCs in vivo and highlight new strategies based on synthetic and biogenic nanocarriers for the development of future anti-CRCSC trials. RESULTS: The CSCs' surface markers, antigens, neoantigens, and signaling pathways supportive CRCSCs or immune cells that are interacted with CRCSCs could be targeted by immune monotherapy or in formulation with developed nanocarriers to overcome the resistant mechanisms in immune evader CRCSCs. CONCLUSION: Identification molecular and cellular cues supporting stemness in CRCSCs and their targeting by nanoimmunotherpy can improve the efficacy of existed therapies or explore novel therapeutic options in future.


Subject(s)
Colorectal Neoplasms , Neoplasm Recurrence, Local , Humans , Neoplasm Recurrence, Local/pathology , Signal Transduction , Colorectal Neoplasms/genetics , Neoplastic Stem Cells/metabolism , Immunotherapy
6.
J Int Med Res ; 51(2): 3000605231154392, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36799092

ABSTRACT

OBJECTIVE: The incidence of thyroglossal duct diseases in the general population is about 7%. We aimed to demonstrate the clinical presentations and management of thyroglossal duct diseases. METHODS: We conducted a retrospective review of all patients who underwent surgery for histopathologically confirmed thyroglossal duct cyst, sinus, or fistula at a single center. RESULTS: A total of 151 cases were included in this study. There were more female patients (87, 58%) than male patients (64, 42%). The patients' ages ranged from 1 to 63 years old. The most prevalent complaint was painless upper midline neck swelling (93.3%). Most cases were diagnosed as thyroglossal duct cysts (137, 90.7%). Six cases (4%) were associated with carcinoma. All the cases were managed using the modified Sistrunk procedure. There were no procedure-related complications, and five cases of recurrence. CONCLUSIONS: Although thyroglossal duct cyst is the most common neck anomaly in children, it may also present with various characteristics later in life. This condition can be managed successfully without complications and with a low recurrence rate.


Subject(s)
Carcinoma , Thyroglossal Cyst , Child , Humans , Male , Female , Infant , Child, Preschool , Adolescent , Young Adult , Adult , Middle Aged , Thyroglossal Cyst/diagnosis , Thyroglossal Cyst/surgery , Thyroglossal Cyst/pathology , Thyroid Gland/pathology , Retrospective Studies
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4473-4478, 2022 07.
Article in English | MEDLINE | ID: mdl-36085824

ABSTRACT

Pulmonary audio sensing from cough and speech sounds in commodity mobile and wearable devices is increasingly used for remote pulmonary patient monitoring, home healthcare, and automated disease analysis. Patient identification is important for such applications to ensure system accuracy and integrity, and thus avoiding errors and misdiagnosis. Widespread usage and deployment of such patient identification models across various devices are challenging due to domain shift of acoustic features because of device heterogeneity. Because of this phenomenon, a patient identification model developed using audio data collected with one type of device is not usable when deployed in another type of device, which is a concern for model portability and general usability. This paper presents a framework utilizing a multivariate deep neural network regressor as a feature translator between source device and target device domains to reduce the effect of domain shift for better model portability. Extensive and empirical experiments of our translation framework consisting of two different human sound (speech and cough) based pulmonary patient identification tasks using audio data collected from 91 real patients demonstrate that it can recover up to 64.8% of lost accuracy due to domain shift across two common and widely used mobile and wearable devices: smartphone and smartwatch. Clinical Relevance- The methods presented in this paper will enable efficient and easy portability of pulmonary patient identification models from cough and speech across various mobile and wearable devices used by a patient.


Subject(s)
Cough , Home Care Services , Acoustics , Cough/diagnosis , Humans , Phonetics , Speech
8.
Article in English | MEDLINE | ID: mdl-36085850

ABSTRACT

Continuous stress exposure negatively impacts mental and physical well-being. Physiological arousal due to stress affects heartbeat frequency, changes breathing pattern and peripheral temperature, among several other bodily responses. Traditionally stress detection is performed by collecting signals such as electrocardiogram (ECG), respiration, and skin conductance response using uncomfortable sensors such as a chestband. In this study, we use earbuds that passively measure photoplethysmography (PPG), core body temperature, and inertial measurements. We have conducted a lab study exposing 18 participants to an evaluated speech task and additional tasks aimed at increasing stress or promoting relaxation. We simultaneously collected PPG, ECG, impedance cardiography (ICG), and blood pressure using laboratory grade equipment as reference measurements. We show that the earbud PPG sensor can reliably capture heart rate and heart rate variability. We further show that earbud signals can be used to classify the physiological responses associated with stress with 91.30% recall, 80.52% precision, and 85.12% F1-score using a random forest classifier with leave-one-subject-out cross-validation. The accuracy can further be improved through multi-modal sensing. These findings demonstrate the feasibility of using earbuds for passively monitoring users' physiological responses.


Subject(s)
Electrocardiography , Photoplethysmography , Blood Pressure , Cardiography, Impedance , Heart Rate , Humans
9.
Front Psychiatry ; 13: 895224, 2022.
Article in English | MEDLINE | ID: mdl-35873273

ABSTRACT

Objective: Depression and anxiety are widespread and chronic among patients with heart disease. We wanted to determine the proportion of heart patients with depression and anxiety levels as well as factors contributing toward depression and anxiety among hospitalized heart disease patients in Dhaka, Bangladesh during the COVID-19 era. Methods: The study comprised a total of 384 participants with a confirmed heart disease diagnosis. We conducted a cross-sectional study from 5th March to 27th June 2021. The hospital-based study admitted patients sequentially with a new or pre-existing heart disease diagnosis to one of Dhaka's two leading hospitals. The Hospital Anxiety and Depression Scale screened all individuals for depression and anxiety. Result: Most of the respondents (88.2%) were male and within the age categories of 51-60 years (32.81%). 96.6% of the patients were married, 30% had no income, 36.6% had only completed classes 1-5, and ~47% resided in rural areas. Approximately 36% of the study participants were former smokers, with 31% current smokers. Borderline abnormal and abnormal levels of anxiety and borderline abnormal and abnormal levels of depression were found in (23.9%, 49.4%) and (55.7%, 13.3%), respectively, of hospitalized patients. Age, residence, profession, monthly income, and chronic disease were significant predictors of anxiety, while only gender remained significantly associated with depression. Conclusion: Hospitalized Bangladeshi patients with heart disease had moderate levels of depression and anxiety. There is a need to develop a quick screening approach in hospitals dealing with hospitalized patients with heart disease to identify those needing extra evaluation and care.

10.
Ann Med Surg (Lond) ; 76: 103444, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35299940

ABSTRACT

Background: Collision tumors are two histologically distinct types of malignancies within the same mass and organ. The aim of this study is to present a case series of thyroid collisions. Methods: This was a multicenter retrospective case series study. The participants were consecutive in order. Socio-demographic and clinical data were obtained from hospital records. Results: The study included eight cases comprising six (75%) females and two (25%) males. The patients had different presentations, including neck swelling, dyspnea, and dizziness. The pathology was successfully determined through fine-needle aspiration. Four patients (50%) underwent lobectomy, whereas the other half (four patients) underwent total thyroidectomy. Conclusion: Collision tumors of papillary thyroid cancer (PTC) and follicular thyroid carcinoma (FTA) or medullary thyroid carcinoma (MTC) and FTA are exceedingly rare phenomena that most commonly affect females. Complete or partial thyroidectomy is the ideal management of choice for these cases and is associated with good survival.

11.
Neuron ; 110(5): 783-794.e6, 2022 03 02.
Article in English | MEDLINE | ID: mdl-34990571

ABSTRACT

Hippocampal place cells underlie spatial navigation and memory. Remarkably, CA1 pyramidal neurons can form new place fields within a single trial by undergoing rapid plasticity. However, local feedback circuits likely restrict the rapid recruitment of individual neurons into ensemble representations. This interaction between circuit dynamics and rapid feature coding remains unexplored. Here, we developed "all-optical" approaches combining novel optogenetic induction of rapidly forming place fields with 2-photon activity imaging during spatial navigation in mice. We find that induction efficacy depends strongly on the density of co-activated neurons. Place fields can be reliably induced in single cells, but induction fails during co-activation of larger subpopulations due to local circuit constraints imposed by recurrent inhibition. Temporary relief of local inhibition permits the simultaneous induction of place fields in larger ensembles. We demonstrate the behavioral implications of these dynamics, showing that our ensemble place field induction protocol can enhance subsequent spatial association learning.


Subject(s)
Hippocampus , Place Cells , Animals , CA1 Region, Hippocampal/physiology , Feedback , Hippocampus/physiology , Mice , Neurons/physiology , Pyramidal Cells/physiology
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2463-2467, 2021 11.
Article in English | MEDLINE | ID: mdl-34891778

ABSTRACT

Respiration rate is considered as a critical vital sign, and daily monitoring of respiration rate could provide helpful information about any acute condition in the human body. While researchers have been exploring mobile devices for respiration rate monitoring, passive and continuous monitoring is still not feasible due to many usability challenges (e.g., active participation) in existing approaches. This paper presents an end-to-end system called RRMonitor that leverages the movement sensors from commodity earbuds to continuously monitor the respiration rate in near real-time. While developing the systems, we extensively explored some key parameters, algorithms, and approaches from existing literature that are better suited for continuous and passive respiration rate monitoring. RRMonitor can passively track the respiration rate with a mean absolute error as low as 1.64 cycles per minute without requiring active participation from the user.


Subject(s)
Respiratory Rate , Wearable Electronic Devices , Algorithms , Humans , Monitoring, Physiologic , Movement
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 5631-5637, 2021 11.
Article in English | MEDLINE | ID: mdl-34892400

ABSTRACT

Mobile and wearable devices are being increasingly used for developing audio based machine learning models to infer pulmonary health, exacerbation and activity. A major challenge to widespread usage and deployment of such pulmonary health monitoring audio models is to maintain accuracy and robustness across a variety of commodity devices, due to the effect of device heterogeneity. Because of this phenomenon, pulmonary audio models developed with data from one type of device perform poorly when deployed on another type of device. In this work, we propose a framework incorporating feature normalization across individual frequency bins and combining task specific deep neural networks for model invariance across devices for pulmonary event detection. Our empirical and extensive experiments with data from 131 real pulmonary patients and healthy controls show that our framework can recover up to 163.6% of the accuracy lost due to device heterogeneity for four different pulmonary classification tasks across two broad classification scenarios with two common mobile and wearable devices: smartphone and smartwatch.Clinical relevance- The methods presented in this paper will enable efficient and easy portability of clinician recommended pulmonary audio event detection and analytic models across various mobile and wearable devices used by a patient.


Subject(s)
Wearable Electronic Devices , Delivery of Health Care , Humans , Machine Learning , Neural Networks, Computer , Smartphone
14.
PLoS One ; 16(11): e0259979, 2021.
Article in English | MEDLINE | ID: mdl-34818360

ABSTRACT

BACKGROUND: Early revascularization and treatment is key to improving clinical outcomes and reducing mortality in acute myocardial infarction (AMI). In low- and middle-income countries such as Bangladesh, timely management of AMI is challenging, with pre-hospital delays playing a significant role. This study was designed to investigate pre-hospital delay and its associated factors among patients presenting with AMI in the capital city of Dhaka. METHODS: This retrospective cohort study was conducted on 333 patients presenting with AMI over a 3-month period at two of the largest primary reperfusion-capable tertiary cardiac care centres in Dhaka. Of the total patients, 239(71.8%) were admitted in the National Institute of Cardiovascular Diseases, Dhaka and 94(28.2%) at Ibrahim Cardiac Hospital & Research Institute, Dhaka Data were collected from patients by semi-structured interview and hospital medical records. Pre-hospital delay (median and inter-quartile range) was calculated. Statistical significance was determined by Chi-square test. Multivariate logistic regression analysis was done to determine the independent predictors of pre-hospital delay. RESULTS: The mean age of the respondents was 53.8±11.2 years. Two-thirds (67.6%) of the respondents were males. Median total pre-hospital delay was 11.5 (IQR-18.3) hours with median decision time from symptom onset to seeking medical care being 3.0 (IQR: 11.0) hours. Nearly half (48.9%) of patients presented to the hospital more than 12 hours after symptom onset. On multivariate logistic regression analysis, AMI patients with absence of typical chest pain [OR 5.21; (95% CI: 2.5-9.9)], diabetes [OR: 1.7 (95% CI: 1.0-2.9)], residing/staying > 30 km away from nearest hospital at the time of onset [OR: 4.3(95% CI = 2.3-7.2)] and belonged to lower and middle class [OR: 1.9(95% CI = 1.0-3.5)] were significantly associated with pre-hospital delays. CONCLUSION: Acute myocardial infarction (AMI) patients with atypical chest pain, diabetes, staying far away from nearest hospital and belonged to lower and middle socioeconomic strata were significantly associated with pre-hospital delays. The findings could have immense implications for improvements about timely reaching of AMI patients to the hospital within the context of their sociodemographic status and geographic barriers of the city.


Subject(s)
Myocardial Infarction/etiology , Patient Acceptance of Health Care/psychology , Time-to-Treatment/trends , Acute Disease/epidemiology , Adult , Aged , Bangladesh , Chest Pain , Cohort Studies , Developing Countries , Female , Heart , Hospital Records , Hospitalization , Humans , Ischemia/physiopathology , Male , Medical Records , Middle Aged , Myocardial Infarction/epidemiology , Reperfusion/adverse effects , Retrospective Studies , Tertiary Care Centers
15.
Neuron ; 107(2): 283-291.e6, 2020 07 22.
Article in English | MEDLINE | ID: mdl-32392472

ABSTRACT

Episodic memory requires linking events in time, a function dependent on the hippocampus. In "trace" fear conditioning, animals learn to associate a neutral cue with an aversive stimulus despite their separation in time by a delay period on the order of tens of seconds. But how this temporal association forms remains unclear. Here we use two-photon calcium imaging of neural population dynamics throughout the course of learning and show that, in contrast to previous theories, hippocampal CA1 does not generate persistent activity to bridge the delay. Instead, learning is concomitant with broad changes in the active neural population. Although neural responses were stochastic in time, cue identity could be read out from population activity over longer timescales after learning. These results question the ubiquity of seconds-long neural sequences during temporal association learning and suggest that trace fear conditioning relies on mechanisms that differ from persistent activity accounts of working memory.


Subject(s)
Association Learning/physiology , Hippocampus/physiology , Memory, Episodic , Nerve Net/physiology , Animals , Behavior, Animal , CA1 Region, Hippocampal/physiology , Conditioning, Operant , Cues , Fear/psychology , Hippocampus/cytology , Image Processing, Computer-Assisted , Memory, Short-Term/physiology , Mice , Mice, Inbred C57BL , Neurons/physiology , Optogenetics
16.
Nanotechnology ; 26(43): 434005, 2015 Oct 30.
Article in English | MEDLINE | ID: mdl-26447742

ABSTRACT

We designed a nickel-assisted process to obtain graphene with sheet resistance as low as 80 Ω square(-1) from silicon carbide films on Si wafers with highly enhanced surface area. The silicon carbide film acts as both a template and source of graphitic carbon, while, simultaneously, the nickel induces porosity on the surface of the film by forming silicides during the annealing process which are subsequently removed. As stand-alone electrodes in supercapacitors, these transfer-free graphene-on-chip samples show a typical double-layer supercapacitive behaviour with gravimetric capacitance of up to 65 F g(-1). This work is the first attempt to produce graphene with high surface area from silicon carbide thin films for energy storage at the wafer-level and may open numerous opportunities for on-chip integrated energy storage applications.

17.
Nanotechnology ; 25(32): 325301, 2014 Aug 15.
Article in English | MEDLINE | ID: mdl-25053702

ABSTRACT

Currently proven methods that are used to obtain devices with high-quality graphene on silicon wafers involve the transfer of graphene flakes from a growth substrate, resulting in fundamental limitations for large-scale device fabrication. Moreover, the complex three-dimensional structures of interest for microelectromechanical and nanoelectromechanical systems are hardly compatible with such transfer processes. Here, we introduce a methodology for obtaining thousands of microbeams, made of graphitized silicon carbide on silicon, through a site-selective and wafer-scale approach. A Ni-Cu alloy catalyst mediates a self-aligned graphitization on prepatterned SiC microstructures at a temperature that is compatible with silicon technologies. The graphene nanocoating leads to a dramatically enhanced electrical conductivity, which elevates this approach to an ideal method for the replacement of conductive metal films in silicon carbide-based MEMS and NEMS devices.

18.
Neuron ; 63(3): 372-85, 2009 Aug 13.
Article in English | MEDLINE | ID: mdl-19679076

ABSTRACT

The entorhinal cortex provides both direct and indirect inputs to hippocampal CA1 neurons through the perforant path and Schaffer collateral synapses, respectively. Using both two-photon imaging of synaptic vesicle cycling and electrophysiological recordings, we found that the efficacy of transmitter release at perforant path synapses is lower than at Schaffer collateral inputs. This difference is due to the greater contribution to release by presynaptic N-type voltage-gated Ca(2+) channels at the Schaffer collateral than perforant path synapses. Induction of long-term potentiation that depends on activation of NMDA receptors and L-type voltage-gated Ca(2+) channels enhances the low efficacy of release at perforant path synapses by increasing the contribution of N-type channels to exocytosis. This represents a previously uncharacterized presynaptic mechanism for fine-tuning release properties of distinct classes of synapses onto a common postsynaptic neuron and for regulating synaptic function during long-term synaptic plasticity.


Subject(s)
Calcium Channels, N-Type/physiology , Hippocampus/cytology , Long-Term Potentiation/physiology , Perforant Pathway/cytology , Recruitment, Neurophysiological/physiology , Synapses/physiology , 2-Amino-5-phosphonovalerate/pharmacology , 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology , Analysis of Variance , Animals , Biophysics , Calcium Channel Blockers/pharmacology , Dose-Response Relationship, Drug , Electric Stimulation/methods , Excitatory Amino Acid Antagonists/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , In Vitro Techniques , Kinetics , Long-Term Potentiation/drug effects , Mice , Mice, Inbred C57BL , Patch-Clamp Techniques/methods , Photons , Pyridinium Compounds/metabolism , Quaternary Ammonium Compounds/metabolism , Synapses/drug effects , Time Factors , omega-Agatoxin IVA/pharmacology
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