Linear Correlation Analysis Research Articles

Does the modified shuttle test exhibit a ceiling effect in healthy and cystic fibrosis children and adolescents?

Introduction: The modified shuttle test-15 (MST-15) is a valid alternative for assessing exercise capacity when a cardiopulmonary exercise testing is not feasible. This study aims to describe the percentage of healthy and cystic fibrosis (CF) children and adolescents reaching the MST-15 ceiling. Additionally, it examines associations between MST-15 distance and demographic, anthropometric, and lung function data. Methods: This retrospective cross-sectional study involved 286 healthy volunteers (11.5 ± 3.3 years) and 70 CF patients (11.9 ± 4.4 years). Data on age, gender, weight, height, body mass index, lung function, and MST-15 were collected. The ceiling effect was determined by the absolute and relative number of participants reaching the 15th level. Univariate linear regression and correlation analyses were conducted to explore associations with MST-15 distance. Results: A ceiling effect for the MST-15 was found in 19 healthy participants (6.6%) and 1 CF patient (1.4%). The ceiling effect was correlated with age (r = 0.777 for healthy; r = 0.538 for CF), with no cases under 10 years and reaching 25% in healthy participants aged 17-19. Regression analysis showed significant associations between age and MST-15 distance in healthy participants (β = 53.6) and CF patients (β = 32.1). Additionally, sex was significantly associated with MST-15 distance in healthy participants (β = 107.0), and FEV1 with MST-15 distance in CF patients (β = 31.0). Conclusions: The ceiling effect on the MST-15 is age-dependent, with no occurrences observed in children under 10 years and a gradual increase in incidence as participants age.

Exploring the prognostic impact of triglyceride-glucose index in critically ill patients with first-ever stroke: insights from traditional methods and machine learning-based mortality prediction

BackgroundThe incidence and mortality of first-ever strokes have risen sharply, especially in the intensive care unit (ICU). Emerging surrogate for insulin resistance, triglyceride-glucose index (TyG), has been linked to stroke prognosis. We aims to explore the relationships between TyG with ICU all-cause mortality and other prognosis, and to develop machine learning (ML) models in predicting ICU all-cause mortality in the first-ever strokes.MethodsWe included first-ever stroke patients from the eICU Collaborative Research Database in 2014–2015 as the primary analysis cohort (then divided into training and internal validation cohorts) and from local hospital’s ICUs as the external validation cohort. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to evaluate the association between TyG and ICU/hospital all-cause mortality. Linear regression and correlation analyses were performed to examine the relationships between TyG with length of ICU/hospital stay and Glasgow Coma Score.ResultsThe primary analysis cohort included 3173 first-ever strokes (median age 68.0 [55.0–68.0] years; 63.0% male), while the external validation cohort included 201 first-ever strokes (median age 71.0 [63.0–77.0] years; 62.3% male). Multivariate Cox proportional hazards models revealed that the high TyG group (TyG ≥ 9.265) was associated with higher ICU (HR 1.92, 95% CI 1.38–2.66) and hospital (HR 1.69, 95% CI 1.32–2.16) all-cause mortality, compared with low TyG group (TyG < 9.265). TyG was also correlated with ICU length of stay (r = 0.077), hospital length of stay (r = 0.042), and Glasgow Coma Score (r = -0.132). TyG and other six features were used to construct ML models. The random forest model performed best in internal validation with AUC (0.900) and G-mean (0.443), and in external validation with AUC (0.776) and G-mean (0.399).ConclusionTyG (optimal cut-off: 9.265) was identified as an independent risk factor for ICU and hospital all-cause mortality in first-ever strokes. The ML model incorporating TyG demonstrated strong predictive performance. This emphasises the importance of insulin resistance (with TyG as a surrogate measure) in the prognostic assessment and early risk stratification of first-time stroke patients.

Christmas article: collisions between roe deer and ambulances

Preoperative templating in hip arthroplasty surgery is crucial for accurate implant selection and reducing postoperative complications. This study examines whether there is a correlation between femoral head size and shoe size, with the aim of simplifying the preoperative planning process. A total of 14 patients had their shoe size and femoral head size measured. Data were analyzed using linear regression and Pearson's correlation analysis to quantify the relationship between the two variables. The Pearson correlation coefficient revealed a value of 0.80 (p = 0.0007), and the linear regression model showed that 63% of the variation in shoe size was based on femoral head size. The study demonstrates a strong and significant correlation between shoe size and femoral head size. This correlation could potentially be used to develop a simple calculation method, where femoral head size = (shoe size - 23.9) / 0.36, which may streamline preoperative planning in orthopedic surgery and reduce workload. None. None.

Accurate location of Ni and W active sites in hierarchical zeolite catalyst for the conversion of cellulose to alcohols

The process of converting cellulose into short-chain alcohols is a critical component of biomass valorization. In this study, we utilized an anion-cation co-directed hydrothermal method and wet impregnation to synthesize a hierarchical MFI zeolite with isolated Ni and W sites. We employed linear correlation analysis to evaluate the influence of pore size, site accessibility, and acidity on product selectivity. Balancing hydrogenation and acidic sites on the catalyst enhanced retro-aldol condensation and hydrogenation during cellulose conversion. Surface acidic sites accelerated glucose retro-aldol condensation, while micropore acidic sites aided in ethylene glycol hydrogenolysis. The close proximity of Ni and W facilitated high selectivity and yield of ethanol through bimetallic synergy. This research presented a novel strategy for preparing hierarchical zeolites with isolated metal sites and provides clarity on the cooperative roles of active sites in Ni-W bimetallic catalysts for cellulose conversion.

Analysis of the Causes of Insomnia in Young and Middle-aged People and Nursing Intervention Strategies of Traditional Chinese and Western Medicine

Objective: To examine insomnia in the modern young and middle-aged population and explore nursing intervention strategies using traditional Chinese and Western medicine. Methods: A total of 255 inpatients and outpatients were sampled from Shenzhen Hospital of Traditional Chinese Medicine. The Sleep Questionnaire for Young and Middle-aged People was used to assess insomnia, and a linear regression model was applied for data analysis. Results: A total of 251 valid questionnaires were collected. Correlation analysis revealed a high incidence of insomnia among respondents. Linear correlation analysis indicated that mental illness or other underlying diseases leading to pain had a significantly positive effect on symptom improvement through Chinese and Western medicine treatments (B = 0.763, P &lt; 0.01). Conversely, work or life pressures (emotional or financial issues) had a significantly negative impact on treatment effectiveness (B = -0.503, P &lt; 0.01). Cross-analysis identified high life or work pressure as the primary cause of insomnia (70.1%). Conclusion: Insomnia is prevalent among the young and middle-aged in modern times, with high work or life pressure being the leading factor.

Experimental study of the compact brazed heat exchanger on the thermal-hydraulic performance

ABSTRACT In this article, the heat transfer and pressure drop characteristics of a compact brazed heat exchanger (CBHE) are experimentally investigated. With the data obtained from the experiments, analyses were carried out to evaluate heat transfer, effectiveness, and pressure drop performance. From the results, it was seen that as the mass fluid rate increases, the heat transfer rate also increases. The highest heat transfer rate is 18,087 W for a mass flow rate of 210 g/s. This value is for Reynolds number 2125.72. The highest average heat transfer coefficient value in the experiments is 2106 W/m2K. In the experiments, it was seen that the efficiency values increased as the Reynolds number increased. The highest effectiveness value is 0.49. As the Reynolds number increased, the pressure drop also increased. The highest pressure loss value was found to be 20,377 Pa. Based on the results obtained from the experiments, linear correlation analysis was also performed to determine whether there is a trend between pressure drop and Re and heat transfer rate and mass flow rate. The correlation coefficient between pressure drop and Re and heat transfer rate and mass flow rate are 0.993217 and 0.979179, respectively.

Effect of kinematics on ground reaction force during single-leg jump landing in children: a causal decomposition approach in jumpers and non-jumpers.

The interaction between joint kinematics and kinetics is usually assessed by linear correlation analysis, which does not imply causality. Understanding the causal links between these variables may help develop landing interventions to improve technique and create joint-specific strengthening programs to reduce reaction forces and injury risk. Therefore, the aim of this study was to analyze the causal interaction between lower limb sagittal kinematics and vertical ground reaction force (VGRF) during single-leg jump landing in children who are jumpers (volleyball and gymnastics) and non-jumpers, using the causal empirical decomposition method. Our hypothesis is that children who participate in jumping sports, compared to those who do not, employ a different joint strategy to regulate ground reaction forces during landing, particularly at the ankle level. Two groups were compared: the jumpers group (n = 14) and the non-jumpers (control group, n = 11). The causal interaction between sagittal kinematics and VGRF was assessed using ensemble empirical mode decomposition (EEMD) and time series instantaneous phase dependence in bi-directional causality. The relative causal strength (RCS) between the time series was quantified as the relative ratio of absolute cause strength between kinematics and VGRF. A significant interaction between joint and group was found for RCS (p = 0.035, η 2 p = 0.14). The post-hoc analysis showed the jumpers group had higher ankle-to-VGRF RCS than the control group (p = 0.017, d = 1.03), while in the control group the hip-to-VGRF RCS was higher than the ankle-to-VGRF RCS (p = 0.004, d = 0.91). Based on the causal decomposition approach, our results indicate that practicing jumping sports increases the causal effect of ankle kinematics on ground reaction forces in children. While non-jumper children rely more on the hip to modulate reaction forces, jumper children differ from non-jumpers by their greater use of the ankle joint. These findings could be used to develop specific training programs to improve landing techniques according to practice level, potentially helping to reduce the risk of injury in both athletes and non-athletes.

High-fat diet stimulated butyric acid metabolism dysbiosis, altered microbiota, and aggravated inflammatory response in collagen-induced arthritis rats.

Research has demonstrated that obesity may be associated with rheumatoid arthritis (RA). In addition, Dysbiosis of intestinal microbiota and their metabolites has been linked to the occurrence and development of RA and obesity. However, the mechanism by which obesity affects RA remains unclear.In this study, we explored the impact of high fat diet(HFD) on collagen-induced arthritis (CIA) rats and revealed its mechanisms based on gut microbiota and metabolomics. Based on diet and modeling, rats were divided into normal group (Con), CIA model group, HFD group (HFD), and HFD + CIA group (HCIA). The effect of HFD on arthritis in CIA rats were investigated based on the arthritis index (AI), weight, blood lipid levels, and inflammatory cytokines. Moreover, HE staining and micro-CT were performed to evaluated the effect of HFD on the pathology of joints and synovial tissues in CIA rats.16S rRNA amplicon sequencing and liquid chromatography-mass spectrometry (LC-MS) were employed to explore changes in gut microbiota and short-chain fatty acids (SCFAs). The AI scores, inflammatory cytokines and bone destruction parameters in the HCIA group were significantly higher than those in the other three groups. The results of 16S rRNA amplicon sequencing and metabolomics showed that compared with the other three groups, the expression of g_Muribaculaceae and butyric acid were reduced in the HCIA group. Spearman and linear correlation analyses revealed a positive correlation between g_Muribaculaceae abundance and butyric acid levels. HFD stimulated butyric acid metabolism dysbiosis, altered microbiota, and aggravated inflammatory response in CIA rats.

Exploring feasibility of fNIRS to assess delayed inhibition effect of prefrontal cortex for acute stress by acupuncture on GV20: a pilot study.

Acupuncture on the acupuncture point GV20 has been considered effective for managing psychoneurological disorders since ancient times, and GV20 is now regularly used to treat stress-related diseases (SRDs), including psychoneurological disorders. Although reports indicating that acupuncture stimulation of GV20 alone regulates cerebral blood flow (CBF) in brain regions associated with SRDs have been scattered, from the perspective of the need for earlier action, the effects on subjective stress as self-reported in the stress state of healthy individuals and CBF changes in related prefrontal cortex (PFC) subregions, which is based as underlying mechanism, remain unclear. Therefore, there is a need to explore effective methods for analyzing such effects. Multiple consecutive mental arithmetic tasks were performed to induce sufficient stress in healthy university students. Real acupuncture or sham acupuncture was performed on GV20, and subjective stress and CBF changes in PFC subregions were observed before and after acupuncture using functional near-infrared spectroscopy, which were analyzed based on the general linear model method and correlation analysis. Subjective stress was suppressed and recovered significantly faster in the true acupuncture group than in the sham acupuncture group. Furthermore, significant negative correlations were found between subjective stress and CBF in several PFC subregions during and after the tasks, with more correlated regions on the left side than on the right side of the PFC. Among them, the CBF of the left ventrolateral PFC (vl-PFC) was suggested to be maintained in the true acupuncture group under repeated tasks load, which was inferred to be correlated with delayed decreases in subjective stress after acupuncture. This pilot study showed that fNIRS is feasible for assessing delayed PFC inhibition in acute stress by acupuncture on GV20. Acupuncture treatment on GV20 resulted in early suppression of subjective stress and early recovery. The neuroscientific rationale for this finding may lie in its effect on maintaining CBF in the left vl-PFC related to delayed inhibition of subjective stress, and would make it reasonable to apply acupuncture to GV20 in healthy individuals. Larger studies are needed to corroborate these findings and obtain reliable conclusions.

Problem-based learning is helpful in encouraging academic institutions to strive for excellence: perceptions of Sudanese physiologists as an illustration

BackgroundProblem-based learning (PBL) is a well-known teaching method which promotes self-directed learning (SDL) in many medical programs worldwide. This study aimed to examine the perceptions of Sudanese physiologists on applying PBL in teaching their physiology courses or sessions.MethodsA cross-sectional survey was conducted with 82 physiologists (70% of the total Sudanese physiologists). The data were collected using questionnaires that included questions about attitudes towards, effectiveness of, and barriers to PBL implementation. The internal reliability of the questionnaire (over 0.7) was good, as measured by Cronbach’s alpha. The Mann‒Whitney U test, Kruskal–Wallis test, multiple linear regression and correlation (Spearman) analysis were performed to assess various factors associated with physiologists’ perceptions of the research domains.ResultsPhysiologists generally had a positive attitude (overall score percentage of 76.9 ± 23.97%) towards PBL compared to other teaching methods and had good perceptions of the effects of PBL (overall score percentage of 77.1 ± 25.13%) on the student learning process. Furthermore, physiologists had a notable knowledge gap about common challenges affecting PBL application (overall score percentage was 56.93 ± 19.43%) at their relevant institutes. Physiologists’ perceptions of common factors affecting PBL application were significantly related to participants currently working inside or outside Sudan (p value = 0.010) and applying PBL at their relevant institutes (p value = 0.008). In addition, the attitude score was significantly associated with the current workplace (governmental/private) classification (B= -14.083, p = 0.031). Additionally, attitude toward PBL had a significant positive correlation with age (r = 0.233, p = 0.005) and the perception score of PBL’s effects on students’ learning processes (r = 0.788, p < 0.001).ConclusionIn general, physiologists have good attitudes towards and perceptions of PBL’s effectiveness, although they are unaware of the main challenges that PBL faces. The findings of this study can help the Federal Ministry of Higher Education make informed decisions about how to improve teaching methodology by implementing such novel approaches.

Indicator dynamics of the “Combating Cardiovascular Diseases” regional program aimed at reducing mortality from acute coronary syndrome

Aim. To analyze the dynamics of the application of medical and organizational technologies for achieving the target reduction of mortality from acute coronary syndrome (ACS) in the region. Materials and methods. In 2018, the research covered 1 regional vascular center (RVC), 8 primary vascular departments (PVD), and 41 medical organizations (MO). In 2022, the structure of medical organizations changed to include 3 RSCs, 9 PSOs, and 39 MOs. The indicators characterizing the provision of medical care to ACS patients in the Irkutsk region were calculated and analyzed. The presence, direction, and strength of correlation between the number of deaths from ACS and the number of medical and organizational activities was studied using linear correlation analysis by the Pearson method. Results. Over time, the share of hospitalization of patients with ACS in the early stages up to 12 hours increased from 42.1% to 46.5%. The mortality rate from ACS decreased by 20.4%, primarily due to a decrease in mortality in the first 24 hours (by 28.7%). The key medical and organizational technologies that have the greatest impact on mortality rates were identified. A strong relationship (r = -0.729) was established between the number of deaths from ACS and the number of patients transferred to the regional vascular center for emergency coronoplasty; two medium-level relationships (r = -0.343) were found between the number of deaths from ACS and the number of hospitalized patients with ACS in the first 12 hours; a correlation (r = -0.415) was determined between the number of deaths from ACS and the number of hospitalized patients who underwent thrombolytic therapy. The linear regression method showed that the availability of such procedures as emergency coronoplasty and thrombolytic therapy has prognostic significance for further reduction of the expected number of deaths from ACS in the region. Conclusion. The creation of the RVC and PVD infrastructure in the region allowed the major indicators of the “Combating Cardiovascular Diseases” regional program to be achieved.

Dark Chocolate's Impact on Low-Grade Endotoxemia in Metabolic Dysfunction-Associated Steatohepatitis.

Background and AimsCocoa may have prebiotic effects and improve gut barrier function. However, it remains unclear whether dark chocolate can reduce lipopolysaccharide (LPS) levels in patients with Metabolic Dysfunction-Associated Steatohepatitis (MASH). This study aims to evaluate the effect of dark chocolate compared to milk chocolate on endotoxemia in patients with MASH. Methods and ResultsNineteen patients with MASH were randomly assigned in a crossover design to consume either 40 g/day of dark chocolate (>85% cocoa) or 40 g/day of milk chocolate (<35% cocoa) for two weeks to evaluate circulating levels of LPS and zonulin. A significant difference between treatments was observed in LPS (p=0.04) and zonulin (p=0.02) levels based on the ANOVA conducted on the crossover study data. Pairwise comparisons revealed that, compared to baseline, after 14 days of dark chocolate consumption, LPS levels decreased from 22±4 to 19±4 pg/dl (-15%), and zonulin levels decreased from 3.2±0.9 to 2.5±0.8 pg/ml (-20%). Linear correlation analysis indicated that the change (Δ) in LPS values before and after chocolate intake correlated with the change (Δ) in zonulin levels (R = 0.340, p=0.03). ConclusionsThis study demonstrates that dark chocolate reduces circulating levels of LPS and zonulin in patients with MASH.

Are attitudes towards infertility associated with gender perception?

Infertility is not life-threatening but is nevertheless an important problem that threatens a couple’s wellbeing due to its negative impact on their emotional health and quality of life. This descriptive, correlational study aimed to determine the relationship between university students’ attitudes towards infertility and their gender perceptions. The study was conducted in a state university with a total of 602 students. Data were collected using a personal information form, the Attitude Toward Infertility Scale (ATIS), and the Gender Perception Scale (GPS). The scales have no cut-off value and higher scores indicating positive perception of gender and infertility. The study data were evaluated with Spearman’s correlation analysis and simple linear regression analysis test was used to analyze the association between GPS and ATIS scores and also the statistical significance was accepted as p&lt;0.05. As a result 63.1% of the students were female; 80.9% had knowledge about infertility and gender inequality. The students’ mean GPS and ATIS scores were 104.60±15.54 (range: 52-125) and 49.11±7.62 (range: 19-60), respectively. GPS and ATIS scores were positively associated in linear regression analysis (β=0.30; p&lt;0.001) and correlation analysis (rho:0.590; p&lt;0.001). The results of this study showed that university students had positive gender perception and attitudes toward infertility. In addition, students’ attitudes toward infertility were directly associated with the modifiable factor of gender perception.

Climatic sensitivity and the growth prospects of Silver fir and European larch in the Carpathians in the light of observed climate changes

One consequence of climate change is the rapid extinction of spruce monocultures in the Carpathians. Therefore, the need has arisen to replace spruce with other highly productive species that ensure the stability and biodiversity of mountain forests, such as the Abies alba and Larix decidua. These co-occurring conifers show different successional and phenological characteristics: L. decidua is a light-demanding species that dominates in the early successional stages, while A. alba is a shade-tolerant tree. This study attempts to identify climatic factors that determine the tree-ring width of fir and larch in order to assess the growth prospects of these species in the context of the ongoing climate change. As a measure of the vitality of trees, tree-ring widths of 42 sub-populations of fir and 36 of larch from the area of the Western Carpathians were used. Regional growth patterns for each species were used to estimate the relationship between temperature/precipitation and radial growth. Linear correlation analyses and nonlinear Random Forest models were used. Fir growth was significantly positively influenced by the high temperature of January–March and July and the high precipitation of February and July of the year of tree-ring formation. Larch growth was positively affected by the high temperature of May and the low precipitation of April and September of the year of tracheid formation. Unlike larch, fir growth increased if May and June of the preceding year were warm. The dominant climatic factor influencing fir growth was February temperature, whereas for larch growth, it was the May temperature of the year of tree-ring formation. Most of the recently observed changes in climatic factors that are important for the growth of both species are favorable. Thus, increasing their share in the Carpathian forests seems fully justified, as this will contribute to the stability, productivity, and biodiversity of the region’s forests.

Multi-scale analysis of nutrient and environmental dynamics in Hongfeng Lake Southwest China

Traditional linear correlation analysis may not fully capture the true relationship between these variables. Therefore, multi-scale running correlation analysis, such as time-dependent intrinsic correlation (TDIC) and continuous wavelet transform based on Hilbert–Huang transform (HHT), provides valuable insights into local correlations and the evolving relationship between nutrients and environmental factors over time. In this study, we investigated seven environmental factors and four water quality nutrient indicators in deep lakes on the Yungui Plateau in southwestern China. The results revealed that there may be strong correlations between environmental factors and nutrient levels during certain periods, while opposite trends may emerge at other times. These variations in correlation could be attributed to uncertain physical processes, spatial heterogeneity, or the impact of different climatic factors on local hydrological processes. Wavelet analysis indicated that changes in environmental factors lag behind those in nutrient levels, particularly on a cycle of about 12 months. This suggests that changes in environmental factors align with natural patterns after the water body has been polluted. These conclusions underscore the complexity and dynamic nature of the relationship between environmental factors and nutrient levels in water bodies, highlighting the importance of employing advanced analysis techniques to capture this complexity.

In situ oxidative stress in patients with epiretinal membrane.

Oxidative stress is an important factor for vitreomacular interface disease development in a theoretical model. The aim of the study was to evaluate the correlation between oxidative stress in the human epiretinal membrane (ERM) and retinal morphological changes. The study included patients scheduled for vitrectomy with epiretinal membrane removal. LogMAR best corrected visual acuity was assessed and optical coherence tomography was performed. Patients were divided into three groups: Type 1 - epiretinal membrane with premacular fibrosis; type 2 - epiretinal membrane with co-existing layer hole; and type 3 - ERM with co-existing full-thickness macular hole. During vitrectomy, epiretinal membranes were collected. Total oxidant status was determined by an automated colorimetric method in homogenates of epiretinal membrane. The Mann-Whitney U test, Kruskal-Wallis test and Spearman linear correlation analysis were used. Statistical significance was set with a level of α = 0.05. Twenty-one Caucasian women (60%) and 14 men (40%) were included in the study. The average age of participants was 74.7years (95% CI: 71.13-75.45). The mean best corrected visual acuity LogMAR value in the group was 0.8 (95% CI: 0.9-0.7). The mean ratio of total oxidant status to protein level in the collected samples was 0.161 (95% CI: 0.08-0.23) µmol/mg of protein. No correlation was found between total oxidant status and the degree of morphological retinal changes. The study found no significant correlation between the level of oxidative stress in epiretinal membrane and retinal morphological changes.

Gathering Validity Evidence for a Simulation-Based Test of Otoscopy Skills.

Otoscopy is a key clinical examination used by multiple healthcare providers but training and testing of otoscopy skills remain largely uninvestigated. Simulator-based assessment of otoscopy skills exists, but evidence on its validity is scarce. In this study, we explored automated assessment and performance metrics of an otoscopy simulator through collection of validity evidence according to Messick's framework. Novices and experienced otoscopists completed a test program on the Earsi otoscopy simulator. Automated assessment of diagnostic ability and performance were compared with manual ratings of technical skills. Reliability of assessment was evaluated using Generalizability theory. Linear mixed models and correlation analysis were used to compare automated and manual assessments. Finally, we used the contrasting groups method to define a pass/fail level for the automated score. A total of 12 novices and 12 experienced otoscopists completed the study. We found an overall G-coefficient of .69 for automated assessment. The experienced otoscopists achieved a significantly higher mean automated score than the novices (59.9% (95% CI [57.3%-62.6%]) vs. 44.6% (95% CI [41.9%-47.2%]), P < .001). For the manual assessment of technical skills, there was no significant difference, nor did the automated score correlate with the manually rated score (Pearson's r = .20, P = .601). We established a pass/fail standard for the simulator's automated score of 49.3%. We explored validity evidence supporting an otoscopy simulator's automated score, demonstrating that this score mainly reflects cognitive skills. Manual assessment therefore still seems necessary at this point and external video-recording is necessary for valid assessment. To improve the reliability, the test course should include more cases to achieve a higher G-coefficient and a higher pass/fail standard should be used.

Changes in IOL power after laser peripheral iridotomy based on multivariate analysis

BackgroundThis study aimed to investigate the effect of laser peripheral iridotomy (LPI) on intraocular lens (IOL) power in patients with primary angle closure disease (PACD), and to construct mathematical models to assess changes in IOL power.MethodsThis study included 58 eyes of PACD patients. IOL Master700 was used to analyze and compare the changes of IOL power and ocular related parameters in each formula before and after LPI. The number of cases with IOL power changes greater than 0.5 diopters (D) in each group were counted and significant differences were analyzed using Fisher’s exact test. Pearson’s linear correlation analysis was used to ascertain the relationship between IOL power changes and ocular parameter changes to establish mathematical models.ResultsNo significant difference was found in calculated IOL power changes before and after LPI in each group. There was significant difference in the number of cases with IOL change values greater than 0.5D between the primary angle closure glaucoma (PACG) and the other two groups for each formula. IOL power changes were mainly associated with △K and △AL. Mathematical models of IOL power changes after LPI were constructed based on linear regression analysis.(PAC group: △IOLHaigis=0.026–2.950×△AL-1.414×△K, △IOLHoffer Q=-3.578×△AL-1.412×△K, △IOLSRK/T=-3.152×△AL-1.114×△K, △IOLHolladay 1=-3.405×△AL-1.291×△K, △IOLHolladay 2=-3.467×△AL-1.483×△K, △IOLBUII=-3.185×△AL-1.301×△K; PACG group:△IOLHaigis=-1.632×△K, △IOLHoffer Q=-3.770×△AL-1.434×△K, △IOLSRK/T=-3.427×△AL-1.102×△K, △IOLHolladay 1=-3.625×△AL-1.278×△K, △IOLHolladay 2=-4.764×△AL-1.272×△K, △IOLBUII=-4.935×△AL-1.304×△K).ConclusionsLPI will cause changes in some ocular parameters in patients with PACD, with great effects on IOL power calculations was observed in patients with PACG. Mathematical models based on multivariate analysis hold promise for predicting IOL power changes subsequent to LPI.

The impact of AI-generated content on content consumption habits of Chinese social media users through Xiaohongshu application

This study aims to analyze the effects of artificial intelligence-generated content and human-generated content on user cognition, interaction and satisfaction in Xiaohongshu application. The samples are 500 active Xiaohongshu users in China's first - and second-tier cities, including white-collar workers, students, freelancers selected through multi-stage random sampling. The research instrument is a questionnaire. Data were analyzed by statistical methods such as multiple linear regression analysis, T-test and Pearson correlation analysis were used to compare the differences between AI-generated content and human-generated content in terms of user satisfaction, time of use, recommendation quality, personalization satisfaction, content creativity and understanding of user needs. The findings revealed that AI-generated content shows significant advantages in improving user satisfaction and interaction, and the conclusions provide empirical support for the content optimization of social media platforms.

Regional Blood Flow Spectral Parameters as Predictors of Epidural-Related Maternal Fever: A Prospective Observational Study

Background: Epidural-related maternal fever (ERMF) is a common phenomenon that appears to be unique to laboring women and presents diagnostic and therapeutic dilemmas for anesthesiologists. It is crucial to identify and predict the occurrence of ERMF at an early stage to improve the outcomes for mothers and infants. This study evaluated the degree of sympathetic blockade induced by epidural labor analgesia (ELA) by quantifying blood flow spectral parameters using Pulsed-wave Doppler (PWD). The aim was to determine the predictive value of these parameters for the onset of ERMF. Methods: A total of 103 women who had vaginal deliveries with ELA were recruited into the study. PWD ultrasound was used to measure peak systolic velocity (PSV, cm/s) and end-diastolic velocity (EDV, cm/s) in the anterior and posterior tibial arteries. Measurements were taken 1 minute before induction of analgesia and at 5-minute intervals for the subsequent 30 minutes. The change of PSV (ΔPSV) and EDV (ΔEDV) at 30 minutes relative to baseline after induction of analgesia was calculated. Participants were categorized into two groups based on their body temperature during labor and delivery: febrile and afebrile. Generalized estimating equations were used to assess differences both between and within groups across multiple time points. The correlation between two variables was analyzed using Spearman's rank correlation coefficient. Receiver operating characteristic (ROC) curves were plotted to ascertain the cut-off values of lower extremity arterial ultrasound flow spectral parameters for predicting ERMF. Results: Of the 103 study participants, 73 were ultimately included for analysis. Thirteen participants (17.8%) in the study developed ERMF. PSV was significantly higher in the febrile group than the non-febrile group at 10 min after ELA (p &lt; 0.05). In contrast, EDV showed a significant difference between the two groups at 15 min after ELA (p &lt; 0.01). Based on linear correlation analysis, there was a positive correlation between PSV and EDV at 30 minutes after analgesia induction and the peak labor temperature (p &lt; 0.05). ROC curve analysis identified a cut-off value of 43.35 and an area under the curve (AUC) of 0.701 for ΔPSV in the anterior tibial artery region (95% confidence interval (CI) 0.525 to 0.878, p = 0.025) and a cut-off value of 29.94 and an AUC of 0.733 for ΔEDV (95% CI 0.590 to 0.877, p = 0.001). The cut-off value for ΔPSV in the region of the posterior tibial artery was 39.96 with an AUC of 0.687 (95% CI 0.514 to 0.860, p = 0.034), and the cut-off value for ΔEDV was 33.10 with an AUC of 0.713 (95% CI 0.558 to 0.869, p = 0.007). Conclusions: Regional blood flow spectral parameters after epidural analgesia induction can predict the occurrence of ERMF by indirectly reflecting the degree of sympathetic activity inhibition. Specifically, the amount of change in peak systolic velocity and end-diastolic velocity relative to baseline parameters 30 min after ELA induction was the most predictive. Clinical Trial Registration: The study has been registered in the Chinese Clinical Trial Registry https://www.chictr.org.cn/ (reference number: ChiCTR2400080507, 31/01/2024).