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1.
Article in English | MEDLINE | ID: mdl-38715897

ABSTRACT

Objectives: Cold snare polypectomy (CSP) is widely performed for small colorectal polyps. However, small colorectal polyps sometimes include high-grade adenomas or carcinomas that require endoscopic resection with electrocautery. This study aimed to evaluate the efficacy and safety of a novel resection technique, hot snare polypectomy with low-power pure-cut current (LPPC-HSP) for small colorectal polyps, compared with CSP and conventional endoscopic mucosal resection (EMR). Methods: Records of patients who underwent CSP, EMR, or LPPC-HSP for nonpedunculated colorectal polyps less than 10 mm between April 2021 and March 2022 were retrospectively evaluated. We analyzed and compared the treatment outcomes of CSP and EMR with those of LPPC-HSP using propensity score matching. Results: After propensity score matching of 396 pairs, an analysis of CSP and LPPC-HSP indicated that LPPC-HSP had a significantly higher R0 resection rate (84% vs. 68%; p < 0.01). Delayed bleeding was observed in only two cases treated with CSP before matching. Perforation was not observed with either treatment. After propensity score matching of 176 pairs, an analysis of EMR and LPPC-HSP indicated that their en bloc and R0 resection rates were not significantly different (99.4% vs. 100%, p = 1.00; 79% vs. 81%, p = 0.79). Delayed bleeding and perforation were not observed with either treatment. Conclusions: The safety of LPPC-HSP was comparable to that of CSP. The treatment outcomes of LPPC-HSP were comparable to those of conventional EMR for small polyps. These results suggest that this technique is a safe and effective treatment for nonpedunculated polyps less than 10 mm.

2.
Global Health ; 20(1): 70, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39358716

ABSTRACT

BACKGROUND AND METHODS: Competition regulation has a strong influence on the relative market power of firms. As such, competition regulation can complement industry-specific measures designed to address harms associated with excessive market power in harmful consumer product industries. This study aimed to examine, through a public health lens, assessments and decisions made by competition authorities in four jurisdictions (Australia, South Africa, the United States (US), and the European Union (EU)) involving three harmful consumer product industries (alcoholic beverages, soft drinks, tobacco). We analysed legal case documents, sourced from online public registers and dating back as far as the online records extended, using a narrative approach. Regulatory decisions and harms described by the authorities were inductively coded, focusing on the affected group(s) (e.g., consumers) and the nature of the harms (e.g., price increases) identified. RESULTS: We identified 359 cases published by competition authorities in Australia (n = 202), South Africa (n = 44), the US (n = 27), and the EU (n = 86). Most cases (n = 239) related to mergers and acquisitions (M&As). Competition authorities in Australia, the US, and the EU were found to make many decisions oriented towards increasing the affordability and accessibility of alcohol beverages, soft drinks, and tobacco products. Such decisions were very often made despite the presence of consumption-reduction public health policies. In comparison, South Africa's competition authorities routinely considered broader issues, including 'Black Economic Empowerment' and potential harms to workers. CONCLUSION: Many of the competition regulatory decisions assessed likely facilitated the concentration of market power in the industries we explored. Nevertheless, there appears to be potential for competition regulatory frameworks to play a more prominent role in promoting and protecting the public's health through tighter regulation of excessive market power in harmful consumer product industries.


Subject(s)
Economic Competition , European Union , Humans , South Africa , United States , Australia , Alcoholic Beverages , Carbonated Beverages , Tobacco Industry/legislation & jurisprudence , Public Health/legislation & jurisprudence , Decision Making , Document Analysis
3.
Sci Rep ; 14(1): 23216, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39369083

ABSTRACT

Power flow (PF) analysis is a foundational computational method to study the flow of power in an electrical network. This analysis involves solving a set of non-linear and non-convex differential-algebraic equations. State-of-the-art solvers for PF analysis, therefore, face challenges with scalability and convergence, specifically for large-scale and/or ill-conditioned cases characterized by high penetration of renewable energy sources, among others. The adiabatic quantum computing paradigm has been proven to efficiently find solutions for combinatorial problems in the noisy intermediate-scale quantum (NISQ) era, and it can potentially address the limitations posed by state-of-the-art PF solvers. For the first time, we propose a novel adiabatic quantum computing approach for efficient PF analysis. Our key contributions are (i) a combinatorial PF algorithm and a modified version that aligns with the principles of PF analysis, termed the adiabatic quantum PF algorithm (AQPF), both of which use Quadratic Unconstrained Binary Optimization (QUBO) and Ising model formulations; (ii) a scalability study of the AQPF algorithm; and (iii) an extension of the AQPF algorithm to handle larger problem sizes using a partitioned approach. Numerical experiments are conducted using different test system sizes on D-Wave's Advantage™  quantum annealer, Fujitsu's digital annealer V3, D-Wave's quantum-classical hybrid annealer, and two simulated annealers running on classical computer hardware. The reported results demonstrate the effectiveness and high accuracy of the proposed AQPF algorithm and its potential to speed up the PF analysis process while handling ill-conditioned cases using quantum and quantum-inspired algorithms.

4.
Sci Rep ; 14(1): 23244, 2024 10 06.
Article in English | MEDLINE | ID: mdl-39370460

ABSTRACT

Microbial fuel cells (MFCs) use the metabolic actions of microorganisms in an anode chamber to convert the chemical energy from wastewater into electrical energy. To improve the MFC power generation performance and chemical oxygen demand (COD) removal efficiency, Stenotrophomonas acidaminiphila was added to the anode chamber of a dual-compartment MFC. In this process, Stenotrophomonas acidaminiphila promotes the degradation of macromolecules such as bis(2-ethylhexyl) phthalate in food waste oil. Additionally, the generated electrical energy reduced Cu2+ in the copper-containing wastewater in the cathode chamber to Cu monomers. The maximum power density of the MFC was 49.5 ± 3.5 mW/m2, the maximum removal efficiencies of COD and Cu2+ were 63.5 ± 5.8% and 96.5 ± 1.0%, respectively, and Cu2+ was reduced to brick-red Cu monomers. This study provides insights into the simultaneous implementation of food waste oil treatment and metal resource recovery.


Subject(s)
Bioelectric Energy Sources , Copper , Wastewater , Copper/metabolism , Wastewater/microbiology , Wastewater/chemistry , Biological Oxygen Demand Analysis , Electrodes , Water Pollutants, Chemical/metabolism , Food Loss and Waste
5.
Chemistry ; : e202403193, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39374185

ABSTRACT

Here in, we have designed two new unfused non-fullerene small molecules based on asymmetric benzo[1,2-b:3.4-b', 6,5-b"]trithiophene (BTT) central donor core and different terminal units, i.e. 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (NFA-4) and 1,3-diethyl-2-thioxodi hydropyrimidine-4,6(1H,5H)-dione (NFA-5) and their optical and electrochemical properties were investigated. Employing a wide band-gap copolymer D18, the binary D18: NFA-4 and D18:NFA-5 bulk heterojunction-based organic solar cells realized an overall power conversion efficiency of about 17.07% and 11.27 %, respectively. The higher value of power conversion efficiency for the NFA-4-based organic solar cells, as compared to the NFA-5 counterpart, is attributed to the enhanced values of short circuit current, open circuit voltage, and fill factor. After the incorporation of NFA-5 into the binary bulk heterojunction D18:NFA-4, the ternary organic solar cells attained a power conversion efficiency of 18.05 %, which is higher than that for the binary counterparts and attributed to the increased values of short circuit current, fill factor, and open circuit voltage. The increased value of short circuit current is associated with the effective utilization of excitons through the energy transfer from the NFA-5 to NFA-4 as the NFA-4 exhibits a more significant dipole moment than the NFA-5 and is effectively dissociated into a free charge carrier.

6.
N Biotechnol ; 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39374895

ABSTRACT

The hydromechanical stress is a relevant parameter for mammalian cell cultivations, especially regarding scale-up processes. It describes the mechanical forces exerted on cells in a bioreactor. The maximum local energy dissipation rate is a suitable parameter to characterize hydromechanical stress. In literature, different studies deal with the effects of hydromechanical stress on CHO cells in stirred tank reactors. However, they often focus on lethal effects. Furthermore, systematic examinations in smaller scales like shake flasks are missing. Thus, this study systematically considers the influence of hydromechanical stress on CHO DP12 cells in shake flask cultivations. By utilizing online monitoring of the oxygen transfer rate, the study simplifies and enhances the resolution of examinations. Results indicate that while lethal effects are absent, numerous sub-lethal effects emerge with increasing hydromechanical stress: The process time is prolonged. The time of glucose and glutamine depletion, and the lactate switch correlate positively linear with the logarithmic average energy dissipation rate while the maximum specific growth rate correlates negatively. Strikingly, the final antibody concentration only declines at the highest tested average energy dissipation rate of 3.84Wkg-1 (only tested condition with a turbulent flow regime and therefore a higher maximal local energy dissipation rate) from about 250mgL-1 to about 180mgL-1. This study presents a straightforward method to examine the impact of hydromechanical stress in shake flasks, easily applicable to any other suspension cell line. Additionally, it offers valuable insights for scale-up processes, for example into stirred tank reactors.

7.
Injury ; : 111914, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39366879

ABSTRACT

BACKGROUND: Occupational injuries impose a substantial global burden, affecting millions of workers annually, which demands urgent attention to enhance workplace safety and health standards. We aimed to outline the frequency, patterns of injury, and clinical characteristics of patients injured by high-rotation cutting tools (grinders) and to pinpoint the neurovascular (nerves and blood vessels) injuries. METHODS: A retrospective study was conducted and included all adult patients hospitalized because of grinder-related injuries at the only level I Trauma Center in the country. The characteristics of patients, mechanism of injury, management and outcomes were analyzed based on the anatomical location of injuries. RESULTS: 127 patients were hospitalized with grinder-related injuries over ten years. The incidence of GRIs showed an increasing trend over the years. All patients were males with a mean (SD) age of 34.9 (9.8) years. The majority were general laborers (66.1 %), injured by portable grinders (86.6 %), and direct blade contact (64.6 %). The median Injury Severity Score (ISS) was 5.0(IQR 4.0-9.0), and the median Glasgow Coma Scale (GCS) at ED was 15 (3-15). The most frequently injured part was the upper extremity (36.2 %), followed by the lower extremity (33.9 %) and the face (27.6 %). One-third of cases had vascular injuries, and 23.6 % had nerve injuries. Suturing was done for all patients; repairs and debridements were performed in 62 % and 58 % of cases, respectively, and 21 % required vascular surgery. Amputations were required in 9.4 % of cases. Thirty patients had nerve injuries involving the median (11 %) and radial (9.4 %) nerves. Among patients who had neurovascular injuries, 30 % (12/40) experienced complications during the hospital stay, while 60 % (24/40) ended up with physical disabilities. CONCLUSION: Individuals affected by power-tool accidents were predominantly young males, mainly general laborers, with a significant proportion being expatriates. The trend of grinder-related injuries increases over time, with portable grinders being a primary source of injuries due to direct contact with the blade. The anatomical injuries mainly include fractures of the upper and lower extremities. Further studies are warranted to understand the cultural aspects and training requirements of workers handling power tools, aiming to achieve sustainable injury prevention effectively.

8.
Cereb Cortex ; 34(10)2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39367728

ABSTRACT

The purpose of this study was to evaluate the influence of high-definition transcranial direct current stimulation (HD-tDCS) on finger motor skill acquisition. Thirty-one healthy adult males were randomly assigned to one of three groups: online HD-tDCS (administered during motor skill learning), offline HD-tDCS (delivered before motor skill learning), and a sham group. Participants engaged in a visual isometric pinch task for three consecutive days. Overall motor skill learning and speed-accuracy tradeoff function were used to evaluate the efficacy of tDCS. Electroencephalography was recorded and power spectral density was calculated. Both online and offline HD-tDCS total motor skill acquisition was significantly higher than the sham group (P < 0.001 and P < 0.05, respectively). Motor skill acquisition in the online group was higher than offline (P = 0.132, Cohen's d = 1.46). Speed-accuracy tradeoff function in the online group was higher than both offline and sham groups in the post-test. The online group exhibited significantly lower electroencephalography activity in the frontal, fronto-central, and centro-parietal alpha band regions compared to the sham (P < 0.05). The findings suggest that HD-tDCS application can boost finger motor skill acquisition, with online HD-tDCS displaying superior facilitation. Furthermore, online HD-tDCS reduces the power of alpha rhythms during motor skill execution, enhancing information processing and skill learning efficiency.


Subject(s)
Electroencephalography , Learning , Motor Skills , Transcranial Direct Current Stimulation , Humans , Male , Motor Skills/physiology , Transcranial Direct Current Stimulation/methods , Electroencephalography/methods , Young Adult , Learning/physiology , Adult , Brain/physiology
9.
Sci Rep ; 14(1): 23318, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39375479

ABSTRACT

The design of the reactant gas flow field structure in bipolar plates significantly influences the performance of proton exchange membrane fuel cells (PEMFCs). In this study, we introduced four innovative U-shaped flow field designs, namely: In-Out Multi-U, Out-In Multi-U, Distro In-Out Multi-U, and Distro Out-In Multi-U. To investigate the impact of these various flow fields on PEMFC performance, we conducted computational fluid dynamics (CFD) numerical simulations, validated through model experiments. Our results indicate that the Distro Out-In Multi-U flow field offers notable advantages compared to the conventional parallel flow field (CPFF) and conventional serpentine flow field (CSFF). These benefits include reduced inlet and outlet pressures, lower liquid water content, more uniform liquid water distribution, and a more even current density distribution. Furthermore, the Distro Out-In Multi-U design demonstrates improved efficiency, consuming less H2 (91.9%) than the CSFF while achieving a higher net power density output (10.1%). As a result, for the same power output, the Distro Out-In Multi-U utilizes only 83.5% of the H2 consumed by the CSFF. In summary, the U-shaped structured flow field exhibits superior output performance, enhanced energy efficiency, and improved resistance to flooding. These findings suggest that the U-shaped flow field design holds significant potential as a reactive flow field for PEMFCs.

10.
Eur J Med Res ; 29(1): 491, 2024 Oct 07.
Article in English | MEDLINE | ID: mdl-39375738

ABSTRACT

BACKGROUND: Over the past decade, numerous studies on potential factors contributing to ventilation-induced lung injury have been carried out. Mechanical power has been pointed out as the parameter that encloses all ventilation-induced lung injury-contributing factors. However, studies conducted to date provide data regarding mechanical power during the early hours of mechanical ventilation that may not accurately reflect the impact of power throughout the period of mechanical ventilatory support on intensive care unit mortality. METHODS: Retrospective observational study conducted at a single center in Spain. Patients admitted to the intensive care unit, > o = 18 years of age, and ventilated for over 24 h were included. We extracted the mechanical power values throughout the entire mechanical ventilation in controlled modes period from the clinical information system every 2 min. First, we calculate the cutoff-point for mechanical power beyond which there was a greater change in the probability of death. After, the sum of time values above the safe cut-off point was calculated to obtain the value in hours. We analyzed if the number of hours the patient was under ventilation with a mechanical power above the safe threshold was associated with intensive care unit mortality, invasive mechanical ventilation days, and intensive care unit length of stay. We repeated the analysis in different subgroups based on the degree of hypoxemia and in patients with SARS CoV-2 pneumonia. RESULTS: The cut-off point of mechanical power at with there is a higher increase in intensive care unit mortality was 18 J/min. The greater the number of hours patients were under mechanical power > 18 J/min the higher the intensive care unit mortality in all the study population, in patients with SARS CoV-2 pneumonia and in mild to moderate hypoxemic respiratory failure. The risk of death in the intensive care unit increases 0.1% for each hour with mechanical power exceeding 18 J/min. The number of hours with mechanical power > 18 J/min also affected the days of invasive mechanical ventilation and intensive care unit length of stay. CONCLUSIONS: The number of hours with mechanical power > 18 J/min is associated with mortality in the intensive care unit in critically ill patients. Continuous monitoring of mechanical power in controlled modes using an automated clinical information system could alert the clinician to this risk.


Subject(s)
COVID-19 , Critical Illness , Intensive Care Units , Respiration, Artificial , Humans , Critical Illness/mortality , Male , Female , Retrospective Studies , Middle Aged , Aged , COVID-19/mortality , COVID-19/therapy , Hospital Mortality , Spain/epidemiology , SARS-CoV-2 , Ventilator-Induced Lung Injury/mortality , Length of Stay
11.
PeerJ ; 12: e17971, 2024.
Article in English | MEDLINE | ID: mdl-39376225

ABSTRACT

Background: Repeat power ability (RPA) assessments traditionally use discrete variables, such as peak power output, to quantify the change in performance across a series of jumps. Rather than using a discrete variable, the analysis of the entire force-time curve may provide additional insight into RPA performance. The aims of this study were to (1) analyse changes in the force-time curve recorded during an RPA assessment using statistical parametric mapping (SPM) and (2) compare the differences in the force-time curve between participants with low and high RPA scores, as quantified by traditional analysis. Materials and Methods: Eleven well-trained field hockey players performed an RPA assessment consisting of 20 loaded countermovement jumps with a 30% one repetition maximum half squat load (LCMJ20). Mean force-time series data was normalized to 100% of the movement duration and analysed using SPM. Peak power output for each jump was also derived from the force-time data and a percent decrement score calculated for jumps 2 to 19 (RPA%dec). An SPM one-way ANOVA with significance accepted at α = 0.05, was used to identify the change in the force-time curve over three distinct series of jumps across the LCMJ20 (series 1 = jumps 2-5, series 2 = jumps 9-12 and series 3 = jumps 16-19). A secondary analysis, using an independent T-test with significance accepted at p < 0.001, was also used to identify differences in the force-time curve between participants with low and high RPA%dec. Results: Propulsive forces were significantly lower (p < 0.001) between 74-98% of the movement compared to 0-73% for changes recorded during the LCMJ20. Post hoc analysis identified the greatest differences to occur between jump series 1 and jump series 2 (p < 0.001) at 70-98% of the movement and between jump series 1 and jump series 3 (p < 0.001) at 86-99% of the movement. No significant differences were found between jump series 2 and jump series 3. Significant differences (p < 0.001) in both the braking phase at 44-48% of the jump and the propulsive phase at 74-94% of the jump were identified when participants were classified based on low or high RPA%dec scores (with low scores representing an enhanced ability to maintain peak power output than high scores). Conclusion: A reduction in force during the late propulsive phase is evident as the LCMJ20 progresses. SPM analysis provides refined insight into where changes in the force-time curve occur during performance of the LCMJ20. Participants with the lower RPA%dec scores displayed both larger braking and propulsive forces across the LCMJ20 assessment.


Subject(s)
Athletic Performance , Hockey , Muscle Strength , Humans , Male , Muscle Strength/physiology , Athletic Performance/physiology , Hockey/physiology , Young Adult , Adult , Exercise Test/methods , Biomechanical Phenomena/physiology , Movement/physiology , Muscle, Skeletal/physiology
12.
Clin Cosmet Investig Dent ; 16: 381-396, 2024.
Article in English | MEDLINE | ID: mdl-39377078

ABSTRACT

This integrative literature review evaluates the effectiveness of power toothbrushes (PTBs) compared to manual toothbrushes (MTBs) across various populations, focusing on plaque removal, gingival health, calculus reduction, and stain removal. PTBs equipped with advanced technologies such as oscillating-rotating and high-frequency sonic mechanisms have been examined for their potential to enhance oral hygiene. Special attention is given to vulnerable groups, including the elderly and individuals with intellectual disabilities, to assess how PTBs meet their specific oral health needs. A comprehensive literature search was conducted in databases including PubMed, Cochrane Library, Embase, and Google Scholar using keywords such as "power toothbrush", "electric toothbrush", "manual toothbrush", "plaque removal", "gingivitis", "calculus", "dental stains", "oral hygiene", "elderly", and "intellectual disabilities". Studies published between 2000 and 2024 were selected based on their relevance to the PTB and MTB comparison, with an emphasis on outcomes related to oral hygiene efficacy. As this review is narrative rather than systematic, it focuses on synthesizing existing knowledge without applying strict inclusion or exclusion criteria. The results indicate that PTBs generally outperform MTBs in reducing plaque, gingivitis, and stains, though the benefits for special populations are less pronounced but still significant. However, practical issues such as user experience and mechanical reliability of PTBs warrant further investigation. In conclusion, this review enhances the understanding of PTB effectiveness, guides consumer choices, and informs future technological advancements in dental care practices.

13.
Clin Trials ; : 17407745241276137, 2024 Oct 08.
Article in English | MEDLINE | ID: mdl-39377196

ABSTRACT

BACKGROUND/AIMS: Stepped-wedge cluster randomized trials tend to require fewer clusters than standard parallel-arm designs due to the switches between control and intervention conditions, but there are no recommendations for the minimum number of clusters. Trials randomizing an extremely small number of clusters are not uncommon, but the justification for small numbers of clusters is often unclear and appropriate analysis is often lacking. In addition, stepped-wedge cluster randomized trials are methodologically more complex due to their longitudinal correlation structure, and ignoring the distinct within- and between-period intracluster correlations can underestimate the sample size in small stepped-wedge cluster randomized trials. We conducted a review of published small stepped-wedge cluster randomized trials to understand how and why they are used, and to characterize approaches used in their design and analysis. METHODS: Electronic searches were used to identify primary reports of full-scale stepped-wedge cluster randomized trials published during the period 2016-2022; the subset that randomized two to six clusters was identified. Two reviewers independently extracted information from each report and any available protocol. Disagreements were resolved through discussion. RESULTS: We identified 61 stepped-wedge cluster randomized trials that randomized two to six clusters: median sample size (Q1-Q3) 1426 (420-7553) participants. Twelve (19.7%) gave some indication that the evaluation was considered a "preliminary" evaluation and 16 (26.2%) recognized the small number of clusters as a limitation. Sixteen (26.2%) provided an explanation for the limited number of clusters: the need to minimize contamination (e.g. by merging adjacent units), limited availability of clusters, and logistical considerations were common explanations. Majority (51, 83.6%) presented sample size or power calculations, but only one assumed distinct within- and between-period intracluster correlations. Few (10, 16.4%) utilized restricted randomization methods; more than half (34, 55.7%) identified baseline imbalances. The most common statistical method for analysis was the generalized linear mixed model (44, 72.1%). Only four trials (6.6%) reported statistical analyses considering small numbers of clusters: one used generalized estimating equations with small-sample correction, two used generalized linear mixed model with small-sample correction, and one used Bayesian analysis. Another eight (13.1%) used fixed-effects regression, the performance of which requires further evaluation under stepped-wedge cluster randomized trials with small numbers of clusters. None used permutation tests or cluster-period level analysis. CONCLUSION: Methods appropriate for the design and analysis of small stepped-wedge cluster randomized trials have not been widely adopted in practice. Greater awareness is required that the use of standard sample size calculation methods can provide spuriously low numbers of required clusters. Methods such as generalized estimating equations or generalized linear mixed models with small-sample corrections, Bayesian approaches, and permutation tests may be more appropriate for the analysis of small stepped-wedge cluster randomized trials. Future research is needed to establish best practices for stepped-wedge cluster randomized trials with a small number of clusters.

14.
Article in English | MEDLINE | ID: mdl-39377868

ABSTRACT

PURPOSE: To introduce a novel methodology for subjective refraction based on power vectors with a conventional phoropter. METHODS: A conventional phoropter was used to measure power vector components of refraction (M, J0 and J45) directly by using the sphere power (for M measurement) and the cylinder power combined with the Jackson cross-cylinders (for J0 and J45 measurements). Conventional subjective refraction was also performed, and this result was mathematically transformed into power vector notation for comparison purposes. Visual acuities with the conventional prescription and the quasi-vector-based prescription were compared. RESULTS: Refractive error from 40 healthy participants was measured by conventional and quasi-vector-based subjective refraction. No differences were found between methods for any of the power vector components of refraction (p > 0.21 in all cases). The visual acuity achieved with the prescriptions yielded similar values (p = 0.85). CONCLUSIONS: Subjective refraction can be measured directly in power vector notation using a conventional phoropter without any additional adaptation and computation.

15.
Behav Res Methods ; 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354129

ABSTRACT

Closed-form (asymptotic) analytical power estimation is only available for limited classes of models, requiring correct model specification for most applications. Simulation-based power estimation can be applied in almost all scenarios where data following the model can be estimated. However, a general framework for calculating the required sample sizes for given power rates is still lacking. We propose a new model-implied simulation-based power estimation (MSPE) method for the z-test that makes use of the asymptotic normality property of estimates of a wide class of estimators, the M-estimators, and give theoretical justification for the approach. M-estimators include maximum-likelihood, least squares estimates and limited information estimators, but also estimators used for misspecified models, hence, the new simulation-based power modeling method is widely applicable. The MSPE employs a parametric model to describe the relationship between power and sample size, which can then be used to determine the required sample size for a specified power rate. We highlight its performance in linear and nonlinear structural equation models (SEM) for correctly specified models and models under distributional misspecification. Simulation results suggest that the new power modeling method is unbiased and shows good performance with regard to root mean squared error and type I error rates for the predicted required sample sizes and predicted power rates, outperforming alternative approaches, such as the naïve approach of selecting a discrete selection of sample sizes with linear interpolation of power or simple logistic regression approaches. The MSPE appears to be a valuable tool to estimate power for models without an (asymptotic) analytical power estimation.

16.
Int J Psychol ; 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354666

ABSTRACT

Ordinal data such as Likert items, ratings or generic ordered variables are widespread in psychology. These variables are usually analysed using metric models (e.g., standard linear regression) with important drawbacks in terms of statistical inference (reduced power and increased type-1 error) and prediction. One possible reason for not using ordinal regression models could be difficulty in understanding parameters or conducting a power analysis. The tutorial aims to present ordinal regression models using a simulation-based approach. Firstly, we introduced the general model highlighting crucial components and assumptions. Then, we explained how to interpret parameters for a logit and probit model. Then we proposed two ways for simulating data as a function of predictors showing a 2 × 2 interaction with categorical predictors and the interaction between a numeric and categorical predictor. Finally, we showed an example of power analysis using simulations that can be easily extended to complex models with multiple predictors. The tutorial is supported by a collection of custom R functions developed to simulate and understand ordinal regression models. The code to reproduce the proposed simulation, the custom R functions and additional examples of ordinal regression models can be found on the online Open Science Framework repository ( https://osf.io/93h5j).

17.
Front Sports Act Living ; 6: 1448197, 2024.
Article in English | MEDLINE | ID: mdl-39359485

ABSTRACT

Introduction: The purpose was to examine the prevalence of low energy availability (LEA), explore dietary behaviors in men collegiate gymnasts (n = 14), and investigate the relationships between energy availability (EA), body composition, and plyometric performance. Methods: Body composition was measured using air displacement plethysmography. Lower- and upper-body peak power (PWRpeak) and modified reactive strength index (RSImod) were calculated from countermovement jump (CMJ) and plyometric push-up (PP) assessments. Energy expenditure was tracked over 3 days, while daily energy and macronutrient intake were recorded. EA was calculated and used to categorize athletes into LEA and non-LEA groups. Pearson correlation coefficients were used to examine relationships between EA, body composition, and performance metrics. Results: 85.7% of athletes (n = 12) exhibited LEA (20.98 ± 5.2 kcals/kg FFM), with non-LEA athletes (n = 2) marginally surpassing the <30 kcal/kg of fat-free mass (FFM) threshold (30.58 ± 0.2 kcals/kg FFM). The cohort (n = 14) consumed insufficient energy (30.5 ± 4.5 kcal/kg/day) and carbohydrates (3.7 ± 1.1 g/kg/day), resulting in LEA (22.36 ± 5.9 kcal/kg/FFM). EA was not correlated with body composition or performance metrics. Discussion: A high prevalence of LEA may exist in men gymnasts, largely due to a low relative energy and carbohydrate intake.

18.
3D Print Addit Manuf ; 11(3): e1108-e1118, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39359594

ABSTRACT

Advances in manufacturing technologies and materials are crucial to the commercial deployment of energy technologies. We present the case of concentrating solar power (CSP) with molten salt (MS) thermal storage, where low-cost, high-efficiency heat exchangers (HXs) are needed to achieve cost competitiveness. The materials required to tolerate the extreme operating conditions in CSP systems make it difficult or infeasible to produce them using conventional manufacturing processes. Although it is technically possible to produce HXs with adequate performance using additive manufacturing, specifically laser powder bed fusion (LPBF), here we assess whether doing so is cost-effective. We describe a process-based cost model (PBCM) to estimate the cost of fabricating a MS-to-supercritical carbon dioxide HX using LPBF. The PBCM is designed to identify modifications to designs, process choices, and manufacturing innovations that have the greatest effect on manufacturing cost. Our PBCM identified HX design and LPBF process modifications that reduced projected HX cost from $750 per kilo-Watt thermal (kW-th) ($8/cm3) to $350/kW-th ($6/cm3) using currently available LPBF technology, and down to $220/kW-th ($4/cm3) with improvements in LPBF technology that are likely to be achieved in the near term. The PBCM also informed a redesign of the HX design that reduced projected costs to $140-160/kW-th ($3/cm3).

19.
Ultrason Sonochem ; 111: 107087, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39362033

ABSTRACT

Food security for the increasing global population is a significant challenge of the current times particularly highlighting the protein deficiencies. Plant-based proteins could be considered as alternate source of the protein. The digestibility and PDCASS value of these proteins are still a concern. Blue proteins, the new approach of utilizing the proteins from aquatic sources could be a possible solution as it contains all the essential amino acids. However, the conjugation of these proteins with fats and glycogen interferes with their techno-functional properties and consequently their applicability. The application of power ultrasound for extraction and modification of these proteins from aquatic sources to break open the cellular structure, increase extractability, alter the protein structure and consequently provide proteins with higher bioavailability and bioactive properties could be a potential approach for their effective utilization into food systems. The current review focuses on the application of power ultrasound when applied as extraction treatment, alters the sulphite and peptide bond and modifies protein to elevated digestibility. The degree of alteration is influenced by intensity, frequency, and exposure time. The extracted proteins will serve as a source of essential amino acids. Furthermore, modification will lead to the development of bioactive peptides with different functional applications. Numerous studies reveal that blue proteins have beneficial impacts on amino acid availability, and subsequently food security with higher PDCAAS values. In many cases, converted peptides give anti-hypertensive, anti-diabetic, and anti-oxidant activity. Therefore, researchers are concentrating on ultrasound-based extraction, modification, and application in food and pharmaceutical systems.

20.
Free Radic Biol Med ; 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39362289

ABSTRACT

The therapeutic application and dose of cisplatin are limited due to its toxicity to normal cells. Therefore, combination treatments might be the solution with a low dose of cisplatin. The combination effect of nanosecond pulsed high-power microwave (HPM) with cisplatin has not been investigated before. In this work, we aimed to investigate and assess the potential synergistic effects and most likely underlying mechanisms resulting from the combination of nanosecond pulsed HPM and cisplatin. Three cancer (SKOV3, H460, and MDA-MB231) and two normal (MRC5 and HGF) cell lines underwent separate treatments with HPM and cisplatin, as well as a combined treatment. A higher reduction of viability was observed in cancer cells using combination treatments following 24-hour incubation. Cell death, membrane permeability, and intracellular reactive oxygen species (ROS) levels exhibit a noteworthy increase in response to combined 60 pulses of HPM (HPM60) and cisplatin (0.5 µM) treatments compared to control and individual treatments. Elevated γ-H2AX levels indicate DNA double-strand breaks in combined treatments. Additionally, upregulation of ATR/ATM, Chk1/Chk2, P53, and caspase 3/8, Bax, PARP, and Bcl2 confirms DNA damage and mitochondrial dysfunction, leading to apoptosis. Remarkably, half maximal inhibitory concentration (IC50) results showed that HPM60 and cisplatin (0.5 µM) resulted in 16 times higher cell death in SKOV3 and H460 cells compared to cisplatin alone. Moreover, the efficacy of this combined treatment led to an over 50% decrease in the viability of cancer cells. On the other hand, normal cells (MRC5 and HGF) exhibited only a minor 3 to 5% decrease in viability under the same treatment conditions. The obtained results elucidate the cellular mechanisms driving cell apoptosis/death, offering insights for potential advancements in cancer therapy through the combined application of nanosecond pulses of HPM and cisplatin. This serves as a first step for future investigations in this domain.

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