Scaling Analysis Research Articles

The universal gaseous detonation dynamics

The present communication proposes a new scaling approach to unify the dynamics of gaseous detonations subject to wall losses in both the narrow channels and small tubes, by compiling the published experimental data of detonations in 23 different mixtures with a very large range of cellular instabilities. A kinetic induction length Δi,loss can be determined from the detonation velocity deficit and detailed chemistry. In order to take into account the sensitivity of the latter length to post-shock temperature fluctuations (through the reduced activation energy θ), which is a partial and indirect marker of the cellular structure, and to bring out energetics (through the Chapman–Jouguet detonation Mach number MCJ), an effective kinetic length of Δi,loss(MCJ4/θ3) was built and has been shown to collapse the different detonation dynamics of various gaseous mixtures, subjected to wall losses, into a single universal curve for detonation velocity deficits.Novelty and Significance: Scaling analysis of large sets of published data of gaseous detonation experiments in narrow channels and small tubes has been made for 23 different mixtures with varied cellular instabilities and activation energies. The universal dynamics of gaseous detonations subject to wall losses in different mixtures has been achieved, for the first time, by adopting an effective kinetic length by taking into account the effect of both the activation energy and the energetics.

Role of Ion Dynamics in Electron‐Only Magnetic Reconnection

AbstractStandard magnetic reconnection couples with both ions and electrons on different scales. Recently, a new type of magnetic reconnection, electron‐only reconnection without the coupling of ions, has been observed in various plasma environments. Standard reconnection typically has a reconnection outflow velocity of about one Alfvén speed. According to the scaling analysis, the electron outflow velocity is expected to be about one electron Alfvén speed in electron‐only reconnection. However, observations and simulations both find that the electron outflows are much slower than the electron Alfvén speed. In this letter, by performing two‐dimensional particle‐in‐cell simulations, we show that this is because ions play a role in electron‐only reconnection. The ions move slower than the electrons in the outflow direction, and such charge separation forms an in‐plane Hall electric field, which prevents the electrons from being accelerated to the electron Alfvén speed in electron‐only reconnection.

Seabed classification in Bahía de Navidad in the Mexican Central Pacific using a single-beam echosounder

This study proposes a methodology for characterizing subtidal habitats along rocky coastlines and adjacent seabeds in the epipelagic zone using a 120 kHz single-beam echo sounder (SBES). The data collected at depths of 15 to 80 m in Bahía de Navidad on the Mexican Central Pacific coast were postprocessed and classified using QTC Impact™ software to obtain three acoustic classes.Using the classified data and ArcMap™ software, a bathymetric map was built for the selection of 19 sampling points for ground truthing and granulometric analysis to create a matrix further subjected to two ordination analyses: principal component analysis (PCA) and nonmetric multivariate scaling analysis (MDS). Additionally, the matrix was adapted into a dummy matrix, which was subsequently used to conduct a Pearson correlation coefficient test.The analyses revealed a strong correlation between the medium-deep-zone acoustic class (20 m to 50 m) and the medium-grain-size sand substrate, as well as a high correlation between the deep-zone acoustic class (50 to 80 m) and finer sand substrates. This study demonstrated the potential of using affordable echosounders as a reliable and feasible alternative for characterizing marine habitats, especially for research institutions in developing countries with limited financial resources.

Scaling analysis of electrodeposited copper and the influence of a modified polysaccharide on surface roughness

The influence of a commercially available modified polysaccharide (HydroStar®, Chemstar Chemical Products) on the roughness of short-term and small-scale copper electrodeposits was investigated using Atomic Force Microscopy (AFM), linear scan profilometry and scaling analysis. Copper was deposited on a 316L stainless steel cathode at 40 °C and 300 A m−2 from an electrolyte containing 40 g L−1 Cu2+, 170 g L−1 H2SO4, 1.5 g L−1 Fe3+, 15 mg L−1 Cl− and either 0, 10, 50 or 100 mg L−1 of HydroStar. Copper deposits produced between 15 and 25 min were imaged using AFM and 2D linear scan profilometry was used to gather surface features of copper samples produced in the range of 120 and 240 min. Scaling analysis was applied to quantify the surface characteristics of limiting roughness (δ) and critical length (LC) from which δ/LC was computed and related to the aspect ratio of surface features. All copper deposits showed a general rise in δ and LC with deposition time but the growth rates decreased when HydroStar was included in the electrolyte indicating that the additive lowers the vertical height of surface features as well as their widths. Furthermore, copper deposits were more consistently produced in the presence of HydroStar and, for a given value of limiting roughness, had surface features with wider base than those created in the absence of the additive. The results show that the modified polysaccharide acts to create smooth copper deposits by generating surface features with lower aspect ratios.

Analysis of the Social Capital Toward Farmers' Independence in the Integrated Farming in the Agrowisata Urban Village of Rumbai District Pekanbaru City

Farmers in the Agrowisata Urban Village use an integrated farming system, and the social capital of farmers can influence the integrated farming system for research objectives, namely, to analyze: (1) the level of integrated agricultural farmer empowerment in the Agrowisata Urban Village, Rumbai District and (2) the relationship of social capital with the independence of farmers integrated in the Agrowisata Urban Village, Rumbai District. This study used a census research method with a population of 45 farmers using primary and secondary data. Data were analyzed using the Likert scale analysis and multiple linear regression. The results showed that the empowerment of integrated agricultural farmers was in the high category with an average of 4.18. Human resources, a productive economy, and institutions owned by integrated agricultural farmers are also in the high category. The relationship of social capital with the independence of integrated agricultural farmers in the Agrowisata Urban Village indicated that norms, productive economy, and institutions have a positive effect or have an influence on the independence of integrated agricultural farmers in the Agrowisata Urban Village Rumba District. Keywords: integrated agriculture, social capital, empowerment, independence

Deciphering stratified structure and microbiota assembly of biofilms from a pyrite-based biofilter driven by mixotrophic denitrification

The precise structure and assembly process of pyrite-based biofilms remain poorly understood. The polysaccharides (PN), proteins (PS), and extracellular DNA were enriched in the soluble extracellular polymeric substance (EPS), loosely bound EPS, and tightly bound EPS, respectively, indicating a significant stratified structure of biofilms. The tryptophan facilitated mixotrophic metabolic processes. Both dominant (>1%) and rare species (<0.01 %) harbored core bacteria, including sulfur autotrophic bacteria, sulfate-reducing bacteria, and heterotrophic bacteria. Furthermore, partial least-squares path modeling quantified the contributions of total phosphorus (TP) (λ = 0.32), dissolved organic matter (DOC) (λ = 0.29), and NH4+–N (λ = 0.26) to variations in the microbial community. Nonmetric multidimensional scaling analysis revealed three distinct stages in biofilm development: colonization (0–36 d), succession (36–149 d), and maturation/old (149–215 d). Furthermore, neutral community model indicated that stochastic processes drove the colonization and maturation/old stages, while deterministic processes dominated the succession stage. This study offered valuable insights into the regulation of pyrite-based engineered ecosystems.

Comparative analysis of Glasgow Coma Scale, quick Sepsis-related Organ Failure Assessment, base excess, and lactate for mortality prediction in critically ill emergency department patients

Abstract OBJECTIVES: It is crucial to promptly identify high-mortality patients in emergency departments and initiate their treatment as soon as possible. Although many parameters have been studied to select patients with high mortality, no comprehensive evaluation exists in previous literature on these parameters in critically ill patients, regardless of patient groups. The aim of this study is to evaluate the Glasgow Coma Scale (GCS), quick Sepsis-related Organ Failure Assessment (qSOFA), blood gas base excess (BE), and blood gas lactate in predicting mortality in critically ill patients admitted to the emergency department. METHODS: This prospective observational cohort study included adult patients with Emergency Severity Index 1–2 (critically ill) admitted to the emergency department. All patients were evaluated by the physician within 10 min, and blood gas samples were taken. The data collection forms recorded the patients’ GCS and qSOFA scores at the time of first evaluation by the physician. The qSOFA score assessment was performed in all patients with ESI levels 1 and 2, regardless of whether infective pathology was suspected. Blood gas BE and lactate values were also from laboratory test results. Patients or their relatives were contacted by phone at the end of the 1st month to obtain information about the clinical condition (survival or mortality). RESULTS: A total of 868 patients were included, with 163 deaths observed within 30 days. GCS score, qSOFA score, and lactate value were significant in predicting mortality within 30 days. While the BE value was significant for predicting 30-day mortality for values equal to or below the lower limit of −1.5 (P &lt; 0.001), it was not significant for values equal to or above the upper limit of +3 (P &gt; 0.05). The most successful prediction model for predicting 30-day mortality was found to be qSOFA with a cutoff value of ≥1. CONCLUSION: In emergency departments, each of the GCS, qSOFA scores, BE, and lactate values can be used independently as a practical mortality prediction model in critically ill patients. Among these four models, qSOFA is the most successful practical mortality prediction model in critically ill patients.

Psychometric properties analysis of Indonesian IKDC scale for managing patients with ACL injury

Psychometric properties analysis of Indonesian IKDC scale for managing patients with ACL injury

Changes in health-related quality of life in young-old and old-old patients undergoing elective orthopedic surgery: A systematic review.

There is a significant gap in research exploring changes in postoperative health-related quality of life (HRQoL) among patients aged 65 years and older undergoing hip or knee arthroplasty. To investigate the variations in HRQoL improvement, as evaluated by patient-reported outcome measures following total hip arthroplasty, total knee arthroplasty, and partial knee arthroplasty between the young-old and old-old adults. We searched six online databases (including MEDLINE, Embase) from their inception dates to May 15, 2023. We included studies using a validated HRQoL assessment tool to evaluate changes in HRQoL in patients aged ≥65 years undergoing hip or knee arthroplasty. These include the EuroQol five-dimension (EQ-5D), Short Form 36 (SF-36) and Short Form 12 (SF-12). The primary outcomes were postoperative HRQoL changes between young-old (65-74 years) and old-old groups (≥75 years). The secondary outcomes included complications, length of stay, and mortality. The search yielded 12,229 articles; twelve studies (n = 103,613) were included. Studies using EQ-5D found no significant differences between young-old and old-old patients after hip and knee arthroplasty. Analyses of SF-36 and SF-12 scales showed no significant age-related differences in postoperative improvements in physical and mental health. Our review of four studies that included multivariable analyses revealed inconsistent associations between age and EQ-5D. Comparisons between the young-old and old-old age groups in postoperative complications, hospital length of stay, and mortality revealed no associated age-related changes in HRQoL. The young-old and old-old patients exhibited comparable improvement in HRQoL following hip or knee arthroplasty. The older patients did not have higher postoperative complications rates, longer hospital length of stay, and increased mortality. While chronological age should be considered when planning hip and knee arthroplasty, greater emphasis should be placed on assessing the comorbidities and functional status of patients.

Flow analysis and fabrication of micro scale controlled surfaces by ultrashort pulse laser for microfluidic device applications

Microfluidics finds a wide range of industrial applications mainly in fields such as biomedical, clinical, electrical, and thermal engineering. Microchannels are the building blocks of most microfluidic devices. Thus, it becomes evident to understand the properties and the effect of the surfaces on the outcomes of devices. In this study, the effect of the shape of microchannels and the roughness elements on the flow is evaluated. Microchannels with three cross-sections and roughness elements of three different geometries are considered. The effect of varying Reynolds numbers on the flow parameters such as Friction factor, Nusselt number, Poiseuille number, pressure drop and surface temperature at the base of the substrate is studied. It is observed that rough microchannels and rectangular roughness elements showed a higher Nusselt number than smooth microchannels. The rough microchannels with triangular roughness elements showed higher friction factors. The surface temperature is higher for the smooth microchannels with triangular roughness elements. Furthermore, to demonstrate the manufacturability of microfluidic channels with controlled surfaces and to validate the preliminary results of the numerical simulations, the ultrashort pulse laser micromachining technique is used to fabricate the microchannels with structures on Polymethyl Methacrylate (PMMA) material.

Utilizing item response theory for the analysis of self-regulated learning scale in mathematics

In the learning process, students must be able to regulate themselves. This is an effort to improve the quality of student learning, especially their learning achievement. The purpose of this study is to empirically analyze the characteristics of self-regulation skills in learning mathematics. The analysis was carried out by utilizing Item Response Theory (IRT) with a Partial Credit Model (PCM). This study is a descriptive quantitative study with the subjects of the study being 123 students of grade 10 of Senior High Schools in Yogyakarta. Data collection was carried out using a questionnaire that had been developed and its item characteristics were analyzed using IRT. The independent learning scale questionnaire in mathematics consists of 16 statement items and measures 5 aspects. Based on all the questions that are feasible to be analyzed using the PCM model, it is known that there are 5 aspects that fit, namely (1) self-confidence, (2) discipline in learning, (3) active in learning, (4) responsibility, and (5) motivation in learning. This instrument can be used to measure students' self-regulation skills in learning mathematics based on their ability level.

Psychometric properties analysis of the Indonesian ACL-RSI scale in patients with ACL injury

Psychometric properties analysis of the Indonesian ACL-RSI scale in patients with ACL injury

Determining user implementation needs for pharmacist-prescribed contraception using concept mapping: A participatory, multiple stakeholder approach

BackgroundAs of October 2024, 29 states and the District of Columbia allow community pharmacists to prescribe hormonal contraceptives. Pharmacists have reported many challenges and barriers to service implementation. MethodsConcept mapping was used to gather insights from diverse stakeholders to identify resources to facilitate implementation of pharmacist-prescribed contraceptive services. Stakeholders included end-users (pharmacy managers, staff pharmacists) and decision-makers (pharmacy owners/executives). Participants' ideas for resources were collected via multi-stakeholder focus groups. Participants then rated each idea (i.e. statement) in terms of importance and feasibility (1 = not at all important/feasible, 4 = extremely important/feasible) and sorted ideas into groups based on similarity via an online survey. Sorting data were analyzed using multidimensional scaling and hierarchical cluster analysis to develop a cluster map. Descriptive statistics were used to analyze rating data to develop a go-zone map, where statements rated above average in terms of both importance and feasibility are plotted in the “go-zone” and are considered the most actionable ideas. ResultsParticipants (focus groups n = 19, survey n = 48) generated 46 unique statements which created four clusters via multidimensional scaling: 1) implementation guidance for practice setup, 2) marketing resources, 3) billing and payment resources, and 4) appointment management. The majority of the statements (13 of 15) considered the most actionable were from the implementation guidance and appointment management clusters. ConclusionsStakeholders seek guidance on implementation, marketing, billing and payment, and appointment management. To increase the ability of community pharmacies to meet the contraceptive needs of patients, resources should be dedicated to creating tools and solutions to address these identified needs.

Turbulence scale and strength analysis in the roughness and inertial sublayers over urban areas: A wind tunnel study

The dissimilarity of dynamics and turbulence structures between the roughness and inertial sublayers (RSL, ISL) over roughness elements show that ISL turbulence is much more homogeneous. Conventional logarithmic law of the wall is merely applicable for the RSL mean-wind-speed profiles. To characterize the turbulence scales and elucidate the mechanism, the flows in the atmospheric surface layer (ASL) over real urban morphology are measured in wind tunnel experiments fabricated by 3D-printing, reduced-scale model of downtown Kowloon Peninsula, Hong Kong. Elevated dispersive stress at urban canopy signifies the influence from individual buildings and inhomogeneous RSL flows. A positive momentum contribution appears in the low-frequency regime. The large-scale turbulence in RSL thus enhances the mixing and transport, resulting in inhomogeneous flows. The contribution from ejection Q2 and sweep Q4 increases and decreases, respectively, with increasing RSL motion strength. The conventional −5/3 law is observed by empirical mode decomposition (EMD) and the largest amplitude fluctuation occurs more often when the turbulence length scale is comparable to the turbulent boundary layer (TBL) thickness. The single-point amplitude modulation (AM) shows that the large- and small-scale turbulence correlates tightly at the bottom of RSL. Besides, the joint probability density function (JPDF) illustrates that accelerating large scales often occur with decelerating small scales, and they are intensified with increasing wall-normal distance. As a result, large-scale turbulence influences substantially the flow structures over urban areas and the small-scale turbulence (even) in RSLs in the vicinity of building obstacles.

Quantification of white matter hyperintensities in type 1 diabetes and its relation to neuropathy and clinical characteristics

AimsThe aims were to quantify periventricular and deep white matter hyperintensities (WMHs) in adults with type 1 diabetes with different neuropathic phenotypes and to correlate WMH measurements to explanatory factors in diabetes. MethodsWMH measurements were obtained from brain magnetic resonance imaging of 56 adults with type 1 diabetes in subgroups including painful diabetic peripheral neuropathy (DPN), painless DPN, without DPN and 20 healthy controls using Fazekas scale and automatic segmentation analysis. ResultsNo differences in Fazekas assessed WMHs were found (individuals with periventricular lesions: diabetes 66 % vs. controls 40 %,p = 0.063, deep lesions: diabetes 52 % vs. controls 50 %,p = 1.0). Using automatic detection, there were no significant differences in count of periventricular (p = 0.30) or deep (p = 0.31) WMHs. Higher periventricular lesion burden was present in diabetes compared with controls (0.21 % vs. 0.06 %,p = 0.048), which was associated with more severe DPN, increased age, decreased cognitive function, and reduced volumetric and metabolic brain measures (all p < 0.05). ConclusionsOur findings indicate increased burden of periventricular WMHs in diabetes which were associated to DPN severity and measures reflecting neurodegeneration. Deep WMHs, often considered as chronic ischemic, were not significantly different. Mechanisms reflecting neurodegeneration and accelerated brain aging could be an overlooked aspect of peripheral and central neuropathy.

Phase transitions in the node, edge, bootstrap, and diffusion percolation models on the Sierpiński carpet

We investigate four types of percolation models—node, edge, bootstrap, and diffusion percolation—in three fractal graphs constructed on the Sierpiński carpet, employing the Monte Carlo method based on the Newman–Ziff algorithm. For each case, we calculate the percolation threshold and critical exponents (ν, γ, and β) through the crossing of percolation probabilities and the finite-size scaling analysis, incorporating correction-to-scaling effects. Our results reveal that critical exponents of the percolation phase transition in the three fractal graphs exhibit universality across all four percolation models. Furthermore, we demonstrate that the hyperscaling relation dν=γ+2β is also valid in the percolation phase transition on the Sierpiński carpet if the spatial dimension d is replaced by the Hausdorff dimension.

Large scale analysis of the SARS-CoV-2 main protease reveals marginal presence of nirmatrelvir-resistant SARS-CoV-2 Omicron mutants in Ontario, Canada, December 2021-September 2023.

In response to the COVID-19 pandemic, a new oral antiviral called nirmatrelvir-ritonavir (PaxlovidTM) was authorized for use in Canada in January 2022. In vitro studies have reported mutations in Mpro protein that may be associated with the development of nirmatrelvir resistance. To survey the prevalence, relevance and temporal patterns of Mpro mutations among SARS-CoV-2 Omicron lineages in Ontario, Canada. A total of 93,082 Mpro gene sequences from December 2021 to September 2023 were analyzed. Reported in vitro Mpro mutations were screened against our database using in-house data science pipelines to determine the nirmatrelvir resistance. Negative binomial regression was conducted to analyze the temporal trends in Mpro mutation counts over the study time period. A declining trend was observed in non-synonymous mutations of Mpro sequences, showing a 7.9% reduction (95% CI: 6.5%-‬9.4%; p<0.001) every 30 days. The P132H was the most prevalent mutation (higher than 95%) in all Omicron lineages. In vitro nirmatrelvir-resistant mutations were found in 3.12% (n=29/929) Omicron lineages with very low counts, ranging from one to 19. Only two mutations, A7T (n=19) and M82I (n=9), showed temporal presence among the BA.1.1 in 2022 and the BQ.1.2.3 in 2022, respectively. The observations suggest that, as of September 2023, no significant or widespread resistance to nirmatrelvir has developed among SARS-CoV-2 Omicron variants in Ontario. This study highlights the importance of creating automated monitoring systems to track the emergence of nirmatrelvir-resistant mutations within the SARS-CoV-2 virus, utilizing genomic data generated in real-time.

Predicting Characteristic Length Scales of Barrier Island Segmentation in Microtidal Environments

AbstractSegmented barrier islands can be found in regions with small tidal ranges. In contrast to tidally dominated barriers, where inlet dynamics are thought to control island length scales, the controls on barrier island length scales in wave‐dominated environments have not been quantified. These microtidal barriers typically have a curved shoreline, suggesting the influence of wave‐driven alongshore sediment transport. Microtidal barriers are also typically hydrodynamically isolated from one another, as weak tidal flows limit interactions between adjoining barriers. To better understand the controls on and scales of barrier segmentation in the relative absence of tides, here we develop a theoretical framework to estimate the alongshore length scales at which a barrier will either breach or heal following a disturbance in the barrier morphology. The non‐dimensional framework compares the timescales of overwash (advective) and alongshore sediment transport (diffusive) processes along barrier island chains. We then apply this framework to modern barrier islands in the microtidal Gulf of Mexico using wave hindcast data and the lengths, widths, heights, and lagoon depths measured from remotely sensed geospatial data and topobathymetric data. We find that most of these barriers are currently longer than their critical length scale, often as a result of coastal restoration efforts. Our critical length scale analysis suggests that most of the Gulf of Mexico barriers are vulnerable to segmentation despite coastal restoration efforts intended to protect fisheries and the mainland coasts.

Validity and Reliability of the Amharic Version of EORTC QLQ-OG25 Among Esophagogastric Cancer Patients inEthiopia.

Cancers of the stomach and esophagus are the fourth and sixth most common causes of cancer-related deaths worldwide, respectively. Although various tools have been developed to assess the quality of life of patients with esophagogastric cancer, EORTC QLQ-C30 and EORTC QLQ-OG25 are the most used all over the world. However, they have not been validated in an Ethiopian context. Therefore, this study aimed to evaluate the psychometric properties of EORTC QLQ-OG25 among Ethiopian patients with esophageal and gastric cancer. EORTC QLQ-OG25 is a 25-item tool with 10 single items and six symptom scales: Eating restrictions, reflux, dysphagia, odynophagia, discomfort and pain, and anxiety. The tool was translated into Amharic according to the EORTC forward-backward translation protocol. To check its validity and reliability, a cross-sectional study among 158 patients was conducted from March to May 2020 at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. The psychometric properties of EORTC QLQ-C30 and EORTC QLQ-OG25 were assessed using multitrait scale analysis, known group validity, convergent validity, and divergent validity. Internal consistency was examined with Cronbach's alpha. Eighty-three (52.5%) of the participants were men; the median age was 50 years (IQR = 18 years). The overall item correlation alpha values ranged between 0.39 and 0.7. All item correlations within their scales were greater than 0.4. The correlation coefficients between all items and their own domain were greater than for other domains. The esophagogastric and core questionnaire correlation ranged from -0.65 to 0.62. The tool showed a significant difference between patients with good physical function and those with impaired physical function. The findings suggest that the Amharic version of EORTC QLQ-OG25 is a valid and reliable tool among patients from Ethiopia with esophagus and gastric cancer. Therefore, we recommend that researchers and clinicians use the core tool together with the specific tool.

Mokken scale analysis of the Internet Gaming Disorder Scale–Short-Form and the Gaming Disorder Test

In recent years, research on Gaming Disorder (GD) has grown substantially with researchers developing different psychometric tools for assessing disordered gaming. Two of the most prominent tools are the Internet Gaming Disorder Scale–Short-Form (IGDS9-SF) and the Gaming Disorder Test (GDT), which assess disordered gaming under the American Psychiatric Association (APA) and the World Health Organisation (WHO) frameworks respectively. The main aim of this study was to assess and compare the scalability, reliability, and validity of both scales to determine if the tools effectively assess GD in a normative sample, through the Mokken Scale Analysis (MSA). A sample of 605 participants (42.31 % female, meanage = 23.98 years, SD = 9.21 years) was recruited for the present study. Results showed that both the IGDS9-SF and GDT were unidimensional, with all items presenting latent monotonicity fitting in the Monotone Homogeneity Model (MHM). Item characteristic curves did not intersect and presented with adequate fit in the Double Monotonicity Model (DMM). These findings further support the psychometric adequacy of the IGDS9-SF and GDT, attesting to their suitability to assess disordered gaming.