Nevin Manimala

J Phys Chem A. 2024 Mar 26. doi: 10.1021/acs.jpca.3c08131. Online ahead of print.

ABSTRACT

Using reactive force field (ReaxFF) and molecular dynamics simulation, we investigate the combustion process of hydrogen-oxygen systems in initial thermal nonequilibrium states with different translational and rovibrational temperatures for oxygen. The system studied in this work contains 300 oxygen molecules and 700 hydrogen molecules with a density of 7 times the air density. For this system, the characteristic relaxation times of oxygen and hydrogen vibrational energies are 0.173 and 0.249 ns, respectively. 0.6% of hydrogen undergoes a chemical reaction with oxygen during the thermal nonequilibrium relaxation stage. For the distribution of translational energy and vibrational energy of oxygen in the thermal nonequilibrium state, the maximum mean error of the statistical distribution in the simulation and the Boltzmann distribution at temperature calculated from the average kinetic energy of molecules is about 2.25 × 10^-5. At the same time, it was observed in the simulation that many-body interactions play a certain role in the combustion process. Furthermore, we compare the ignition time and temperature rise behavior of different combustion mechanisms and molecular dynamics simulations starting from the thermal equilibrium state. These results will provide meaningful references for the construction of thermal nonequilibrium combustion chemical reaction mechanisms.

PMID:38530707 | DOI:10.1021/acs.jpca.3c08131

JACC Heart Fail. 2024 Mar 23:S2213-1779(24)00180-X. doi: 10.1016/j.jchf.2024.02.016. Online ahead of print.

ABSTRACT

Clinical trials are vital for assessing therapeutic interventions. The associated data monitoring committees (DMCs) safeguard patient interests and enhance trial integrity, thus promoting timely, reliable evaluations of those interventions. We face an urgent need to recruit and train new DMC members. The Heart Failure Collaboratory (HFC), a multidisciplinary public-private consortium of academics, trialists, patients, industry representatives, and government agencies, is working to improve the clinical trial ecosystem. The HFC aims to improve clinical trial efficiency and quality by standardizing concepts, and to help meet the demand for experienced individuals on DMCs by creating a standardized approach to training new members. This paper discusses the HFC’s training workshop, and an apprenticeship model for new DMC members. It describes opportunities and challenges DMCs face, along with common myths and best practices learned through previous experiences, with an emphasis on data confidentiality and need for quality independent statistical reporting groups.

PMID:38530701 | DOI:10.1016/j.jchf.2024.02.016

Elife. 2024 Mar 26;12:RP90156. doi: 10.7554/eLife.90156.

ABSTRACT

The understanding of eco-evolutionary dynamics, and in particular the mechanism of coexistence of species, is still fragmentary and in need of test bench model systems. To this aim we developed a variant of SELEX in vitro selection to study the evolution of a population of ∼10¹⁵ single-strand DNA oligonucleotide ‘individuals’. We begin with a seed of random sequences which we select via affinity capture from ∼10¹² DNA oligomers of fixed sequence (‘resources’) over which they compete. At each cycle (‘generation’), the ecosystem is replenished via PCR amplification of survivors. Massive parallel sequencing indicates that across generations the variety of sequences (‘species’) drastically decreases, while some of them become populous and dominate the ecosystem. The simplicity of our approach, in which survival is granted by hybridization, enables a quantitative investigation of fitness through a statistical analysis of binding energies. We find that the strength of individual resource binding dominates the selection in the first generations, while inter- and intra-individual interactions become important in later stages, in parallel with the emergence of prototypical forms of mutualism and parasitism.

PMID:38530348 | DOI:10.7554/eLife.90156

JMIR Res Protoc. 2024 Mar 26;13:e53722. doi: 10.2196/53722.

ABSTRACT

BACKGROUND: Vitamin D deficiency has been associated with hypertensive disorders in pregnancy (HDP). The risk of developing HDP was reported to be further augmented among individuals with a vitamin D receptor (VDR) genetic variant. However, the reported roles of VDR variants in hypertensive disorders are inconsistent among different populations. Given the relatively higher incidence of vitamin D deficiency among Malaysian pregnant women and the high incidence of HDP in this population, we hypothesize that there may be associations between the risk of vitamin D deficiency and HDP with VDR genetic variants.

OBJECTIVE: This paper outlines the protocol for a study to determine the association of vitamin D status and VDR sequence variants among Malaysian pregnant women with HDP.

METHODS: This prospective study consists of two phases. The first phase is a cross-sectional study that will entail gathering medical records, a questionnaire survey, and laboratory testing for vitamin D status, with a planned recruitment of 414 pregnant women. The questionnaire will be utilized to assess the risk factors for vitamin D deficiency. The vitamin D status will be obtained from measurement of the vitamin D (25-hydroxyvitamin D₃) level in the blood. The second phase is a case-control study involving a Malay ethnic cohort with vitamin D deficiency. Participants will be divided into two groups with and without HDP (n=150 per group). Genomic DNA will be extracted from the peripheral blood monocytes of participants using the Qiagen DNA blood kit, and VDR sequence variants will be determined using polymerase chain reaction-high-resolution melting (PCR-HRM) analysis. Sanger sequencing will then be used to sequence randomly selected samples corresponding to each identified variant to validate our PCR-HRM results. The VDR genotype and mutation frequencies of BsmI, ApaI, TaqI, and FokI will be statistically analyzed to evaluate their relationships with developing HDP.

RESULTS: As of December 2023, 340 subjects have been recruited for the phase 1 study, 63% of whom were determined to have vitamin D deficiency. In the phase 2 study, 50 and 22 subjects have been recruited from the control and case groups, respectively. Recruitment is expected to be completed by March 2024 and all analyses should be completed by August 2024.

CONCLUSIONS: The outcome of the study will identify the nonmodifiable genetic components contributing to developing vitamin D deficiency leading to HDP. This will in turn enable gaining a better understanding of the contribution of genetic variability to the development of HDP, thus providing more evidence for a need of customized vitamin D supplementation during pregnancy according to the individual variability in the response to vitamin D intake.

TRIAL REGISTRATION: ClinicalTrials.gov NCT05659173; https://clinicaltrials.gov/study/NCT05659173.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/53722.

PMID:38530345 | DOI:10.2196/53722

Physiol Meas. 2024 Mar 26. doi: 10.1088/1361-6579/ad37ee. Online ahead of print.

ABSTRACT

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia associated with significant health ramifications, including an elevated susceptibility to ischemic stroke, heart disease, and heightened mortality. Photoplethysmography (PPG) has emerged as a promising technology for continuous AF monitoring for its cost-effectiveness and widespread integration into wearable devices. Our team previously conducted an exhaustive review on PPG-based AF detection before June 2019. However, since then, more advanced technologies have emerged in this field. This paper offers a comprehensive review of the latest advancements in PPG-based AF detection, utilizing digital health and artificial intelligence (AI) solutions, within the timeframe spanning from July 2019 to December 2022. Through extensive exploration of scientific databases, we have identified 57 pertinent studies. Our comprehensive review encompasses an in-depth assessment of the statistical methodologies, traditional machine learning techniques, and deep learning approaches employed in these studies. In addition, we address the challenges encountered in the domain of PPG-based AF detection. Furthermore, we maintain a dedicated website to curate the latest research in this area, with regular updates on a regular basis.&#xD.

PMID:38530307 | DOI:10.1088/1361-6579/ad37ee

Phys Med Biol. 2024 Mar 26. doi: 10.1088/1361-6560/ad37ea. Online ahead of print.

ABSTRACT

Accurate and reproducible tumor delineation on Positron Emission Tomography (PET) images is required to validate predictive and prognostic models based on PET radiomic features. Manual segmentation of tumors is time-consuming whereas semi-automatic methods are easily implementable and inexpensive. This study assessed the reliability of semi-automatic segmentation methods over manual segmentation for tumor delineation in Head and Neck Squamous Cell Carcinoma (HNSCC) PET images.

Approach: We employed manual and six semi-automatic segmentation methods (Just Enough Interaction (JEI), watershed, grow from seeds (GfS), flood filling (FF), 30% SUVmax and 40%SUVmax threshold) using 3D slicer software to extract 128 radiomic features from FDG-PET images of 100 HNSCC patients independently by three operators. We assessed the distributional properties of all features and considered 92 log-transformed features for subsequent analysis. For each paired comparison of a feature, we fitted a separate linear mixed effect model using the method (two levels; manual method versus one semi-automatic method) as a fixed effect and the subject and the operator as the random effects. We estimated different statistics ¬- the intraclass correlation coefficient agreement (aICC), limits of agreement (LoA), total deviation index (TDI), coverage probability (CP) and coefficient of individual agreement (CIA) – to evaluate the agreement between the manual and semi-automatic methods.

Main Results: Accounting for all statistics across 92 features, the JEI method consistently demonstrated acceptable agreement with the manual method, with median values of aICC = 0.86, TDI = 0.94, CP = 0.66, and CIA = 0.91.

Significance: This study demonstrated that the JEI method is a reliable semi-automatic method for tumor delineation on HNSCC PET images.&#xD.

PMID:38530298 | DOI:10.1088/1361-6560/ad37ea

Photobiomodul Photomed Laser Surg. 2024 Mar 26. doi: 10.1089/photob.2023.0136. Online ahead of print.

ABSTRACT

Objective: To assess the impact of intravascular laser irradiation of blood (ILIB) on the primitive carotid artery (PCA) hemodynamic variables, specifically blood pressure (BP) and heart rate (HR), in mastectomized patients undergoing hormone blocker treatments. Materials and methods: This study is a controlled, experimental, and randomized clinical trial. Patients were allocated into two groups: the experimental group (G1)-patients who received ILIB therapy using a 660 nm laser targeted at the PCA, and the control group (G2)-patients who did not receive ILIB therapy. Clinical research was conducted weekly, with measurements of systolic blood pressure (SBP), diastolic blood pressure (DBP), and HR. The Mann-Whitney U test for independent samples was used, with a significance level of α = 0.05. Results: Systemic photobiomodulation on the PCA did not demonstrate a statistically significant difference in relation to SBP and DBP. However, for HR, the p-value was <0.05, indicating a significant difference between G1 and G2. The initial mean p > decreased from 142.3 to 116.4 mmHg in G1, and from 130.4 to 119.8 mmHg in G2. The DBP varied from 78.8 to 72.8 mmHg in G1, and from 79.1 to 74.2 mmHg in G2. A statistically significant difference was observed in HR, decreasing from 81.3 to 62.06 bpm in G1, and changing minimally from 74.1 to 75.1 bpm in G2. A considerable reduction was present in the timing of application. Conclusions: ILIB therapy applied to the PCA induces a reduction in BP and, more notably, HR in mastectomized women using the tamoxifen or aromatase inhibitors.

PMID:38530295 | DOI:10.1089/photob.2023.0136

J Radiol Prot. 2024 Mar 26. doi: 10.1088/1361-6498/ad37c7. Online ahead of print.

ABSTRACT

Statistically significant increases in ischemic heart disease (IHD) mortality with cumulative occupational external radiation dose were observed in the National Registry for Radiation Workers (NRRW) cohort. There were 174541 subjects in the NRRW cohort. The start of follow up was 1955, and the end of the follow-up for each worker was chosen as the earliest date of death or emigration, their 85th birthday or December 31, 2011. The dose-response relationship showed a downward curvature at a higher dose level > 0.4 Sv with the overall shape of the dose-response relationship best described by a linear-quadratic model. The smaller risk at dose > 0.4 Sv appears to be primarily associated with workers who started employment at a younger age (< 30 years old) and those who were employed for more than 30 years. We modelled the dose response by age-at-first exposure. For the age-at-first exposure of 30+ years old, a linear dose-response was the best fit. For age-at-first exposure <30 years old, there was no evidence of excess risk of ischemic heart disease mortality for radiation doses below 0.1 Sv or above 0.4 Sv, excess risk was only observed for doses between 0.1-0.4 Sv. For this age-at-first exposure group, it was also found that the doses they received when they were less than 35 years old or greater than 50 years old did not contribute to any increased IHD risk.

PMID:38530293 | DOI:10.1088/1361-6498/ad37c7

J Orthop Sports Phys Ther. 2024 Mar 26:1-28. doi: 10.2519/jospt.2024.12342. Online ahead of print.

ABSTRACT

OBJECTIVE: To compare the effects of personalized supervised group-based programs (group physical therapy programs) to usual one-on-one physical therapy care (usual physical therapy care) on disability for military personnel suffering from low back pain, rotator cuff-related shoulder pain, patellofemoral pain syndrome or lateral ankle sprain. Secondary outcomes were pain severity, pain-related fear, health-related quality of life and patients’ satisfaction with their condition and care. DESIGN: Non-inferiority pragmatic randomized clinical trial. METHODS: One hundred and twenty military personnel from the Canadian Armed Forces, experiencing one of four targeted musculoskeletal disorders, were consecutively recruited, and randomly assigned to group physical therapy programs or usual physical therapy care. Disability, pain severity, pain-related fear, and health-related quality of life outcomes were measured at 6, 12, and 26 weeks after baseline. Satisfaction with treatment was evaluated at the end of the intervention. Intention-to-treat analyses using linear mixed models with random effects were used to compare the effects of interventions. Chi-squared tests were used to compare satisfaction. RESULTS: There were no significant Time x Group interactions for any of the primary and secondary outcomes (Time × Group p>.67). Satisfaction with treatment also did not differ between groups (p>.05). Statistically significant and clinically important improvements were observed in both groups for all outcomes after 12 weeks (Time effect: p<.01), except for health-related quality of life (p=.13). CONCLUSION: Group physical therapy programs were not inferior to usual physical therapy care for managing pain, functional capacity, and patients’ satisfaction with care of military personnel presenting with various musculoskeletal disorders. Both interventions led to clinical and statistical improvement in pain and function in the mid and long term. Group physical therapy could be an effective strategy to enhance access to care..

PMID:38530230 | DOI:10.2519/jospt.2024.12342

Physiother Theory Pract. 2024 Mar 26:1-10. doi: 10.1080/09593985.2024.2334752. Online ahead of print.

ABSTRACT

BACKGROUND: Hemophilia is characterized by degenerative joint damage. Patients with hemophilic arthropathy present joint damage, reduced range of motion, and decreased strength and functional capacity. Myofascial release therapy aims to decrease pain and improve tissue mobility and functionality.

OBJECTIVES: To evaluate the safety and efficacy of myofascial release therapy in patients with hemophilic ankle arthropathy.

METHOD: Single-blind randomized controlled trial. Fifty-eight adult patients with hemophilia were randomly allocated to the experimental group (myofascial release therapy with foam roller) or the control group (no intervention whatsoever). The daily home protocol of myofascial release therapy for the lower limbs using a foam roller lasted eight consecutive weeks. The primary variable was the safety of myofascial release therapy (weekly telephone follow-up). The secondary variables were pain intensity (visual analog scale), range of motion (goniometer), functional capacity (2-Minute Walk Test) and muscle strength (dynamometer), at baseline and at 8 and 10 weeks.

RESULTS: During the experimental phase, none of the patients in the experimental group developed ankle hemarthrosis. There were statistically significant changes in time*group interaction in ankle dorsal flexion (F_[1.75] = 10.72; p < .001), functional capacity (F_[1.16] = 5.24; p = .009) and gastrocnemius strength (F_[2] = 26.01; p < .001). The effect size of the changes after the intervention was medium-large in pain intensity (d = -1.77), functional capacity (d = 1.34) and gastrocnemius strength (d = 0.76).

CONCLUSION: Myofascial release therapy is a safe form of physical therapy for patients with hemophilia. Myofascial release therapy can effectively complement prophylactic pharmacological treatment in patients with hemophilic arthropathy, improving range of motion in dorsal flexion, functional capacity and gastrocnemius strength.

PMID:38530214 | DOI:10.1080/09593985.2024.2334752