Functional Variables Research Articles

Percent Predicted vs. Absolute Six-Minute Walk Distance as Predictors of Lung Transplant-Free Survival in Fibrosing Interstitial Lung Diseases.

Fibrosing interstitial lung diseases (ILDs) often progress despite treatment and become life-threatening, with lung transplant (LTx) remaining the only curative option. Six-minute walk distance (6MWD) is increasingly recognized as reliable predictor of clinical course, especially when longitudinally considered. The use of reference equations to express 6MWD as percent predicted (6MWD%) has not been previously studied in fibrosing ILDs. We sought to investigate whether the prognostic power of 6MWD% is superior to that of 6MWD expressed in meters (6MWD-m). A retrospective, multicenter cohort analysis was conducted on both idiopathic pulmonary (IPF) and non-IPF fibrosing ILD patients. Patients were divided into a discovery (n = 211) and a validation (n = 260) cohort. Longitudinal changes of 6MWD% and lung function parameters were simultaneously considered. LTx-free survival at 3years from baseline was the endpoint. Competing risks of death and LTx were considered. Baseline 6MWD% and its longitudinal changes were significant predictors of LTx-free survival and independent from lung function variables. In both cohorts, on multivariate cox proportional hazard regression analysis, receiver operating characteristics analysis and Kaplan-Meier estimates, 6MWD% was consistently, but only slightly superior to 6MWD-m as a predictor of LTx-free survival. 6MWD% has only a slight, yet detectable advantage over 6MWD-m as a predictor of survival in fibrosing ILDs. Utilizing 6MWD% may aid in risk stratification, treatment monitoring, and LTx timing optimization. However, available reference equations do have predicting limitations. Refined predictive equations and standardizing reporting practices are therefore needed to further enhance the clinical utility of 6MWD% in fibrosing ILDs.

Dispersal shapes compositional and functional diversity in aquatic microbial communities

ABSTRACT Segregation and mixing shape the structure and functioning of aquatic microbial communities, but their respective roles are challenging to disentangle in field studies. We explored the hypothesis that functional differences and beta diversity among stochastically assembled communities would increase in the absence of dispersal. Contrariwise, we expected biotic selection during homogenizing dispersal to reduce beta and gamma diversity as well as functional variability. This was experimentally addressed by examining the compositional and functional changes of 20 freshwater bacterial assemblages maintained at identical conditions over seven growth cycles for 34 days and subjected to two consecutive dispersal regimes. Initial dispersal limitation generated high beta diversity and led to the repeated emergence of community types that were dominated by particular taxa. Compositional stability and evenness of the community types varied over successive growth cycles, reflecting differences in functional properties. Carbon use efficiency increased during cultivation, with some communities of unique composition outperforming the replicate community types. Homogenizing dispersal led to high compositional similarity and reduced gamma diversity. While a neutral and a competition-based (Elo-rating) model together largely explained community assembly, a pseudomonad disproportionally dominated across communities, possibly due to interaction-related genomic traits. In conclusion, microbial assemblages stochastically generated by dispersal limitation can be gradually “refined” into distinct community types by subsequent deterministic processes. Segregation of communities represented an insurance mechanism for highly productive but competitively weak microbial taxa that were excluded during community coalescence. IMPORTANCE We experimentally assessed the compositional and functional responses of freshwater bacterial assemblages exposed to two consecutive dispersal-related events (dispersal limitation and homogenizing dispersal) under identical growth conditions. While segregation led to a decreased local diversity, high beta diversity sustained regional diversity and functional variability. In contrast, homogenizing dispersal reduced the species pool and functional variability of the metacommunity. Our findings highlight the role of dispersal in regulating both diversity and functional variability of aquatic microbial metacommunities, thereby providing crucial insight to predict changes in ecosystem functioning.

Healthcare costs in relation to kidney function among older people: the SCOPE study.

In this study, a comprehensive analysis of costs of chronic kidney disease (CKD) was performed, to understand factors associated with the economic burden of the disease in a multicentre international framework. The impact on costs of demographics, socio-economics, clinical, and functional variables was tested in 2204 subjects aged 75years or more attending outpatient clinics in Europe using a multicentre 2-year prospective cohort study. By means of collected resources consumption and unit cost data a comprehensive cost database was built and then investigated using multilevel regression modeling. Overall, hospitalization, medications and specialist visits were the main cost items, with a notable variability among countries. Estimated yearly costs were 4478€ ± 9804€, rising up to 6683€ ± 10,953€ for subjects with estimated Glomerular Filtration Rate (eGFR) < 30. Costs increased significantly according to the severity of the disease, gender and age. Clinical and functional covariates were also significantly associated with CKD-related total costs, even after correcting for the inter-country variability. Findings corroborate the importance of multidimensional assessment of participants with CKD, as multimorbidity and functional disability produce a detrimental impact on participant's prognosis and cost of care. Preservation of functional impairment and adequate management of comorbidities may thus help decreasing the overall consumption on health care resources in CKD patients, especially in older people.

Predicting post-hepatectomy liver failure in patients with hepatocellular carcinoma: nomograms based on deep learning analysis of gadoxetic acid-enhanced MRI.

This study aimed to develop nomograms for predicting post-hepatectomy liver failure (PHLF) in patients with hepatocellular carcinoma (HCC), using deep learning analysis of Gadoxetic acid-enhanced hepatobiliary (HBP) MRI. This retrospective study analyzed patients who underwent gadoxetic acid-enhanced MRI and hepatectomy for HCC between 2016 and 2020 at two referral centers. Using a deep learning algorithm, volumes and signal intensities of whole non-tumor liver, expected remnant liver, and spleen were measured on HBP images. Two multivariable logistic regression models were formulated to predict PHLF, defined and graded by the International Study Group of Liver Surgery: one based on whole non-tumor liver measurements (whole liver model) and the other on expected remnant liver measurements (remnant liver model). The models were presented as nomograms and a web-based calculator. Discrimination performance was evaluated using the area under the receiver operating curve (AUC), with internal validation through 1000-fold bootstrapping. The study included 1760 patients (1395 male; mean age ± standard deviation, 60 ± 10 years), with 137 (7.8%) developing PHLF. Nomogram predictors included sex, gamma-glutamyl transpeptidase, prothrombin time international normalized ratio, platelets, extent of liver resection, and MRI variables derived from the liver volume, liver-to-spleen signal intensity ratio, and spleen volume. The whole liver and the remnant liver nomograms demonstrated strong predictive performance for PHLF (optimism-corrected AUC of 0.78 and 0.81, respectively) and symptomatic (grades B and C) PHLF (optimism-corrected AUC of 0.81 and 0.84, respectively). Nomograms based on deep learning analysis of gadoxetic acid-enhanced HBP images accurately stratify the risk of PHLF. Question Can PHLF be predicted by integrating clinical and MRI-derived volume and functional variables through deep learning analysis of gadoxetic acid-enhanced MRI? Findings Whole liver and remnant liver nomograms demonstrated strong predictive performance for PHLF with the optimism-corrected area under the curve of 0.78 and 0.81, respectively. Clinical relevance These nomograms can effectively stratify the risk of PHLF, providing a valuable tool for treatment decisions regarding hepatectomy for HCC.

Mandibular Advancement Devices in Obstructive Sleep Apnea and Its Effects on the Cardiovascular System: A Comprehensive Literature Review

Background: Obstructive sleep apnea syndrome (OSA) is a chronic inflammatory disease characterized by endothelial dysfunction and cardiovascular complications. Continuous positive airway pressure (CPAP) is the standard treatment, hence poor adherence has prompted interest in mandibular advancement devices (MAD) as an alternative. This comprehensive review aimed to explore the effects of MAD therapy on oxidative stress, inflammation, endothelial function, and its impact on the cardiovascular risk in OSA patients. Results: MAD therapy significantly reduces the apnea-hypopnea index (AHI), improves serum nitric oxide (NOx) concentrations, reduces oxidative stress markers, and enhances endothelial function. Animal studies indicated that MAD reduces myocardial fibrosis and attenuates inflammatory markers. While both CPAP and MADs improve endothelial function and heart rate variability, CPAP is more effective in reducing OSA severity. Nevertheless, MAD has higher compliance, contributing to its positive impact on cardiovascular function. Moreover, CPAP and MADs have similar effectiveness in reducing cardiovascular risk. Conclusions: MAD therapy is an effective alternative to CPAP, particularly for patients with mild to moderate OSA as well as those intolerant to CPAP. It offers significant improvements in endothelial function and oxidative stress. Further studies are needed to assess MAD therapy in comprehensive OSA management.

Microbial Life in Playa-Lake Sediments: Adapted Structure, Plastic Function to Extreme Water Activity Variations

Saline shallow lakes in arid and semi-arid regions frequently undergo drying episodes, leading to significant variations in salinity and water availability. Research on the impacts of salinity and drought on the structure and function of biofilms in hypersaline shallow lakes is limited. This study aimed to understand the potential changes of biofilms in playa-lake sediments during the drying process. Sediments were sampled at different depths (surface, subsurface) and hydrological periods (wet, retraction, and dry), which included a decrease in water activity (aw, the availability of water for microbial use) from 0.99 to 0.72. aw reduction caused a greater effect on functional variables compared to structural variables, indicating the high resistance of the studied biofilms to changes in salinity and water availability. Respiration and hydrolytic extracellular enzyme activities exhibited higher values under high aw, while phenol oxidase activity and prokaryote biomass increased at lower aw. This shift occurred at both depths but was more pronounced at the surface, possibly due to the more extreme conditions (up to 0.7 aw). The increased levels of extracellular polymeric substances and carotenoids developed at low aw may help protect microorganisms in high salinity and drought environments. However, these harsh conditions may interfere with the activity of hydrolytic enzymes and their producers, while promoting the growth of resistant prokaryotes and their capacity to obtain C and N sources from recalcitrant compounds. The resilience of biofilms in hypersaline lakes under extreme conditions is given by their resistant biochemichal structure and the adaptability of their microbial functioning.

Renal endowment in men and women: start from the beginning.

The development of the human kidney leads to the establishment of nephron endowment through a process influenced by both genetic and environmental factors. There is individual variability regarding nephron endowment and factors including aging and pathological conditions contribute to the decline in the number of nephrons, impacting renal function. Genetic determinants, such as mutations in crucial developmental genes like Pax2, and epigenetic mechanisms mediated by key enzymes including sirtuin 3, play critical roles in the regulation of the number of nephrons, with implications for kidney disease susceptibility. Sexual dimorphism significantly influences kidney development and function, with the number of nephrons being significantly lower in females, consistent with lower female birth weight, which is considered a surrogate for nephron endowment. Also, although females have fewer nephrons, they experience a slower decline in GFR compared to males. Gender disparity in chronic kidney disease progression has been attributed to factors such as metabolism, oxidative stress, renal hemodynamics, and sex hormones. Understanding the complexities of nephron endowment variability, genetic determinants, and sexual dimorphism in kidney development and function is crucial for elucidating the mechanisms underlying individual kidney disease susceptibility and progression. Further research in this field holds promise for the development of personalized approaches to kidney disease prevention, management, and treatment.

Towards Holistic Functional Task Analysis

ABSTRACTTask analysis (TA) can contribute to work systems design, accident investigation, risk assessment, human error identification, planning, and training. Despite the advantages of existing sequential and hierarchical methods, they decompose tasks into their structure and focus on the order in which tasks are accomplished. They do not trace all interactions among elements/subtasks/operations at different levels. As the complexity of tasks increases, not keeping track of all interactions may result in poor, unwanted outcomes. This research introduces a different approach to TA that decomposes tasks into their constituent functions, describes the functionality of the overall work system, traces (dynamic nonlinear) interactions among functions, and highlights the role of functional variability in forming emergent outcomes. This approach to TA is called functional task analysis (FTA). A case study on nursing work was used to demonstrate the suitability of the FTA approach. The findings of this study show that the FTA approach contributes to task modeling by building a nonsequential, nonhierarchical functional model of a complex task considering dynamic, nonlinear interactions among functions. The FTA also contributes to task description by explaining different ways a task can be accomplished. It also increases the understanding, interpretation, and analysis of how changes in work conditions shape good/acceptable and poor/unacceptable outcomes. The FTA can complement the TA by adding some aspects, including functionality, nonlinearity, dynamics, and emergence, that the TA does not normally consider. The findings highlight how the functional approach to TA can be deployed as an alternative (or complement) to other task analysis methods.

Association between functional capacity and family functionality with frailty in older adults with cardiovascular risk in southwestern Colombia

The changes associated with aging are multidimensional and multifactorial, with the geriatric syndrome of frailty being its most problematic and complex expression. This syndrome leads to vulnerability, disproportionate changes in health status, and functional decline, making its effective identification and comprehensive management necessary. To describe the sociodemographic, clinical, and functional characteristics of older adults with cardiovascular risk in Southwestern Colombia. This study has an observational, cross-sectional, and analytical design. The selected population included older adults enrolled in a cardiovascular and metabolic risk program in Popayán (Cauca). A multivariate analysis explored the relationship between frailty and certain sociodemographic, clinical, and functional variables. A total of 293 older adults participated, primarily women (69.6%), with an average age of 71.23 years. Among them, 77.1% were classified as independent in basic activities and 56.3% in instrumental activities of daily living, with autonomy being more prevalent among men. Additionally, 71.1% of women and 43.8% of men were classified as prefrail. The bivariate analysis identified a relationship between frailty and variables such as sex, age, marital status, educational level, occupation, calf circumference, functional capacity, instrumental capacity, and family functionality. The multivariate analysis showed a higher frailty/prefrailty prevalence (55%) in women. Most participants were classified as prefrail; dependency and frailty were more prevalent in women, suggesting the need for preventive strategies and interventions from a gender-differentiated approach.

Relationship between heart rate variability and echocardiography indices of cardiac function in healthy individuals.

This study evaluated the relationship between HRV and echocardiography indices of cardiac function. Healthy individuals (N = 30) aged 33 ± 10 years old, underwent short-term resting HRV assessment and transthoracic echocardiography with speckle tracking analysis. Time domain - (i.e. R-R interval, root mean square of successive RR interval difference (RMSSD), standard deviation of normal RR intervals (SDNN) and frequency domain-measures of HRV (i.e. high-frequency power (HF), low-frequency power (LF), high-frequency normalised (HFnorm) and low-frequency normalised (LFnorm)). Echocardiography indices of cardiac function included; Left ventricular ejection fraction (LVEF), left- and right-ventricular global longitudinal strain (LV-GLS, and RV GLS), left atrial strain: left atrial reservoir (LAres), left atrial conduit (LAcon) and left atrial contraction (LACT). The mean values for HRV time-domain measures were: R-R (991 ± 176 ms), SDNN (50.9 ± 21.5 ms), and RMSSD (46.8 ± 29.4 ms); and frequency-domain: LF (727 ± 606 ms2), HF (415 ± 35 ms2), LFnorm (56 ± 19.4) and HFnorm (36.5 ± 18.8). Mean values for indices of cardiac function were LVEF (59.9% ± 2.8%), LV-GLS (19.2% ± 1.4%), RV-GLS (21.7% ± 2.7%), LAres (36.8% ± 6.99%), LAcon (26.2% ± 6.95%) and LACT (12.3% ± 3.56%). There was a significant negative relationship between HF and LV-GLS (r = -0.47, p = 0.01) and RMSSD and LVEF (r = -0.39, p = 0.03) respectively. Heart rate variability measures such as high frequency power and RMSSD are associated with left ventricle systolic function in healthy individuals.

Unwrapping the Intricate Interplay Between Energy Dependency and Macroeconomic Volatility in OECD Countries

While research has explored the connection between oil prices and macroeconomic performance, there is limited understanding of the interaction between overseas energy imports dependency and macroeconomic fluctuations. This work addresses the foregoing study using the augmented mean group (AMG) econometrics technique on panel data of 29 OECD net energy‐importing countries from 2001 to 2021. The long‐run finding unearthed that energy dependency intensifies macroeconomic instability, confirming that relying on overseas energy imports will hamper the smooth functioning of domestic economic machinery in the form of energy supply interruption. Besides energy dependency, this study uses government consumption spending, regulatory quality, and globalisation as control variables in macroeconomic instability function. The long‐run outcomes further depict that government consumption spending and globalisation aggravate macroeconomic instability while regulatory quality reduces it. These findings are further checked by applying the pooled mean group‐autoregressive distributed lag (PMG‐ARDL) method. In conclusion, this study provides policy implications to prioritise domestically produced energy use and diversify energy sources by increasing the share of clean energy in the total energy mix.

Systematic identification and expression profiling of calmodulin-binding transcription activator genes reveal insights into their functional diversity against pathogens in sugarcane

The calmodulin-binding transcription activator (CAMTA) proteins in plants play significant roles in signal-transduction, activation of regulatory networks, and defense response against environmental stressors. In this study we systematically identified a total 17 CAMTA genes (named as SsnpCAMTAs) in Saccharum spontaneum Np-X genome. Moreover, SsnpCAMTAs exhibited diverse physio-chemical and gene structural attributes. Notably, eight SsnpCAMTA gene pairs displayed segmental duplication events, while CAMTA genes from S. spontaneum Np-X and Arabidopsis thaliana shared homology relationship. In-vitro interaction networking showed that SsnpCAMTA1 and SsnpCAMTA2 were the core protein which interacted with each other as well as with other four different proteins (SsnpCAMTA5/7/13/17). To check functional variability, the expression profiles of SsnpCAMTAs were quantified in transcriptomic and proteomic datasets triggered by Xanthomonas albilineans (Xa) and Acidovorax avenae subsp. avenae (Aaa). The temporal expression of SsnpCAMTA4/5 was ranged between 1.7–3.5 folds in sugarcane cultivars triggered by Xa infection. Most of the SsnpCAMTAs exhibited irregular expression profile in sugarcane cultivars triggered by Aaa infection. Additionally, transcript expression profiles of eight candidate genes SsnpCAMTA1/2/5/7/8/12/13/17 were determined by RT-qPCR assay in sugarcane cultivars Zhongtang3 (resistant to smut) and ROC22 (susceptible to smut) under Sporisorium scitamineum pathogen infection. Interestingly, the transcript expression of SsnpCAMTA5 was upregulated from 1.4 to 10.8 folds as compared to control in both cultivars, while SsnpCAMTA8 was downregulated in both cultivars. Overall, our results provide valuable candidate gene resources for the development of disease-resistant sugarcane cultivars in the face of current climate change scenarios.

Short-term mortality and associated factors among older hospitalized patients: A narrative retrospective analysis of end-of-life care in an acute geriatric unit

ObjectivesTo explore short-term mortality and its predictors among older patients hospitalized in a acute geriatric ward (AGW) in Northwestern Italy. DesignRetrospective observational single-center cohort study. Material and methodsPatients consecutively admitted for any reason between June 2021 and May 2022 were included in the analysis. Along with sociodemographic, clinical, and functional variables, prognosis estimation (Palliative Prognostic Index; PPI) at the time of admission was registered. Short-term all-cause mortality (in-hospital and within 3 months of discharge) was the primary outcome. ResultsAbout one-third of the total sample died in the short-term (32.4 %). Along with PPI score (OR 1.115, 95 %CI 1.034–1.202), short-term mortality was independently associated with functional dependency (OR 1.278, 95 %CI 1.170–1.395). ConclusionsThe high short-term mortality in our sample should call for the inclusion of palliative prognostic tools within the in-hospital comprehensive geriatric assessment to better recognize and appropriately manage older patients at the end of life.

Predictive Indicators of Cryotolerance and Fertility in Bovine Sperm: Evaluating Fresh Semen Quality to Improve AI Outcomes With Frozen-Thawed Sperm.

The success of artificial insemination (AI) with frozen-thawed semen in cattle is influenced by both female factors and sperm quality. In terms of sperm quality, prior studies indicate that the ability of frozen-thawed bovine sperm to fertilise an oocyte is dependent on their quality and resilience to cryopreservation. Cryopreservation induces oxidative stress, leading to ultrastructural damage in the sperm. This study aimed to determine whether the quality of fresh semen can identify bulls with good and poor sperm freezability. This difference between fresh and frozen semen from the same bull allows us to predict fertility. Motility and kinetic parameters were assessed using computer-assisted sperm analysis (CASA), while six functional variables were evaluated through flow cytometry, both before and after the freeze-thaw process on the sperm from 13 bulls. Invivo fertility was measured using 90-day non-return rates. The principal component analysis (PCA) of eight sperm variables post-thaw identified one principal component explaining 81.19% of the total variance and classified the bulls into two groups: Poor freezability bulls (progressive motility: 48.12% ± 8.41%; viability: 77.51% ± 7.61%) and good freezability bulls (progressive motility: 58.64% ± 6.64%; viability: 88.12% ± 2.52%). Bulls with higher freezability showed better sperm viability and motility, as well as lower levels of ROS, superoxides and intracellular calcium before cryopreservation that were significantly correlated with higher non-return rates (NRR). The results underscore the importance of assessing the quality and functionality of fresh semen to predict the fertility potential of cryopreserved sperm. This approach can aid in selecting ejaculates with the best potential for successful artificial insemination, ultimately improving reproductive performance in dairy cattle.

Exploring the impact of occupational exposure: A study on cardiovascular autonomic functions of male gas station attendants in Sri Lanka.

Fuel dispensing at fuel stations is performed manually by unprotected male gas station attendants in Sri Lanka, who have long working hours. These workers are exposed to hydrocarbon fuels associated with multiple health effects by modulation of the autonomic nervous system. This study was performed to determine cardiovascular autonomic functions among fuel pump attendants in Sri Lanka. Fuel pump attendants (n = 50) aged between 19 and 65 years were identified for the study from seven fuel stations. They were compared with age- and gender-matched controls (n = 46) without occupational exposure to fuel. A physical examination was performed before the autonomic function and heart rate variability (HRV) assessment. There were no significant differences in weight, height, or BMI between the study and the control populations (p > 0.05). Both the systolic blood pressure (SBP) (Mann Whitney U (MWU) = 743.5, p = 0.003) and diastolic blood pressure (DBP) (MWU = 686.5, p = 0.001) were significantly higher among the gas station attendants compared to controls. Valsalva ratio was significantly higher among the study group (MW U = 874.00, p = 0.043) compared to controls. The HRV analysis showed significantly higher SDNN and SD2 (MWU = 842.00, p = 0.034, and MWU = 843.50, p = 0.035 respectively) among the gas station attendants compared to controls. The changes to the cardiovascular autonomic parameters among those exposed to fuel vapor as a gas station attendant indicate an increase in sympathetic outflow to the vessels. In the occupational setting as fuel pump attendants need periodic monitoring.

A biopsychosocial approach to phenotyping people with knee osteoarthritis awaiting total knee arthroplasty: A secondary cohort analysis

BackgroundPrevious research showed chronic post-total knee arthroplasty (TKA) pain in 20% of people with knee osteoarthritis (KOA). Various preoperative biopsychosocial-related factors have been described, but phenotyping people with KOA awaiting TKA based on these factors is still lacking. This could be relevant to understanding differences in TKA surgery responses. ObjectiveTo identify phenotypes in people with KOA awaiting TKA and differences in post-TKA pain based on preoperative biopsychosocial factors. MethodsPeople with KOA awaiting TKA in 4 hospitals in Belgium and the Netherlands were included. A cross-sectional latent profile analysis was conducted on structural, metabolic, functional, pain-related, psychological and social variables. Concurrent validity was tested using 3-step multinomial logistic regression. The difference in one-year post-TKA pain was examined with linear mixed model analysis. ResultsTwo hundred and seventeen participants were included in the latent profile analysis with a mean (SD) age of 65.5 (7.7) years, including 109 women. A model with 2 phenotypes differed in 14 out of 21 variables. Participants with phenotype 2 (28%) had a higher body mass index (BMI), higher chance of having less structural damage (KOA grade), lower mean quadriceps strength and physical function (Knee Society Scoring System functional and 30-second chair stand test), higher pain intensity, number of pain locations, and indices of central sensitisation (temporal summation, central sensitisation inventory score, and lower pressure pain thresholds), higher pain catastrophising, anxiety and depression, and higher post-TKA pain intensity compared to phenotype 1 (72%). Concurrent validity was confirmed in 3 out of 4 variables. ConclusionsPhenotype 2 (28%) with nociplastic pain characteristics in combination with worse psychological factors, BMI, functional and structural factors, and phenotype 1 (72%) not representing these characteristics were identified. Phenotype 2 had worse pain intensity scores after TKA compared to phenotype 1. Attention to the characteristics of phenotype 2 is warranted concerning post-TKA pain. Database registrationThe protocol is registered at ClinicalTrials.gov (NCT05380648).

Simulation model calibration with dynamic stratification and adaptive sampling

ABSTRACT Calibrating simulation models that take large quantities of multi-dimensional data as input is a hard simulation optimization problem. Existing adaptive sampling strategies offer a methodological solution. However, they may not sufficiently reduce the computational cost for estimation and solution algorithm’s progress within a limited budget due to extreme noise levels and heteroscedasticity of system responses. We propose integrating stratification with adaptive sampling for the purpose of efficiency in optimization. Stratification can exploit local dependence in the simulation inputs and outputs. Yet, the state-of-the-art does not provide a full capability to adaptively stratify the data as different solution alternatives are evaluated. We devise two procedures for data-driven calibration problems that involve a large dataset with multiple covariates to calibrate models within a fixed overall simulation budget. The first approach dynamically stratifies the input data using binary trees, while the second approach uses closed-form solutions based on linearity assumptions between the objective function and concomitant variables. We find that dynamical adjustment of stratification structure accelerates optimization and reduces run-to-run variability in generated solutions. Our case study for calibrating a wind power simulation model, widely used in the wind industry, using the proposed stratified adaptive sampling, shows better-calibrated parameters under a limited budget.

Sleep and Respiratory Parameters After Lung Transplantation in Adult Patients With Cystic Fibrosis.

We aimed to explore the prevalence and predictive factors of sleep-disordered breathing (SDB) in patients with cystic fibrosis (pwCF) after lung transplantation (LTX). We prospectively recruited adult pwCF who underwent LTX in our hospital from 2013 to 2022 and invited them for an attended overnight polysomnography (PSG) 1year after transplantation. The apnea-hypopnea index (AHI) was the primary outcome, and SDB was defined as an AHI≥5. Demographic, anthropometric, cardiometabolic, drug treatment, and pulmonary function variables were compared between pwCF with and without SDB. Multiple regression analysis was used to identify significant predictors of SDB. For a subset of participants who had available PSG before transplantation, sleep parameters were compared pre-post transplantation. Sixty-two pwCF (31 females) were enrolled. Thirty participants had SDB, but only 11 of them had moderate-to-severe SDB (AHI≥15). The average Epworth Sleepiness Scale (ESS) score indicated the absence of excessive daytime sleepiness. Older age (p<0.001), male sex (p<0.001), and smaller thoracic gas volume (p=0.002) significantly predicted higher AHI. Comparison between pre- and post-transplantation polysomnographic data showed a significant increase in the percentage of slow wave sleep (p=0.047), as well as a significant improvement in mean nocturnal oxygen saturation (p=0.007). A statistically significant increase in the AHI was also observed (p=0.047), but its clinical importance is uncertain (p=0.476 for the increase in the ESS score). We may conclude that SDB is prevalent in pwCF after LTX, but its severity is mild. Older male pwCF with greater improvement in lung hyperinflation after transplantation might be at risk for SDB and should be followed for symptoms or signs of sleep apnea.

Effects of Vegan and Omnivore Diet on Post-Downhill Running Economy and Muscle Function

Objectives The objective of this study was to examine the difference between the extent of muscle damaging exercise on muscle function variables of vegans and omnivores. Methods Twenty recreationally trained participants completed the study. Participants were assigned to either vegan (n = 10) or omnivore (n = 10) groups. Subjects completed a consent visit followed by 2 visits consisting of running exercise sessions and test familiarization. They returned to the laboratory for visit 4 3-5 days after visit 3 to complete the testing battery. Following the testing, the participants performed a downhill run on the treadmill at −15% grade and approximately 70% of their speed at VO2peak and repeated the testing battery upon completion. Participants were asked to track their food intake. Visits 5, 6, and 7 took place 24, 48, and 72 h following the downhill running protocol, respectively, and consisted of the same testing battery used during visit 4. The detection of differences was performed using two-way (group x time) mixed factorial ANOVA with repeated measures. Results No group x time interactions were noted for running economy or any of the dependent variables. Main effects of time were found for muscle thickness (p<.001) with small effect sizes (d=-0.194 to d=-0.265), pain pressure threshold (p=.002) with medium effect sizes (d=.460 to d=.461), NPRS scale (p<.001) with large effect sizes (d = -0.776 to d=-1.520), and jump height (p<.002) with small to medium effect sizes (d=.304 to d=.438). Nutritional analysis compared the two groups revealed no difference (p>.05) between relative intake of macronutrients and that both exceeded typical recommendations for protein (vegan group − 1.4 g/kg, omnivore group − 1.6 g/kg). Conclusion The lack of differences in recovery between the groups suggests that nutritional adequacy may play a role in recovery. Recovery from downhill running might be influenced by several factors beyond diet, such as exercise protocol intensity, individual fitness levels, and age.

Effect of chest expansion resistance exercise and respiratory muscle stretching on respiratory function and gait endurance in patients with stroke.

Limited chest expansion and asymmetry in the respiratory muscles after a stroke lead to poor ventilation and reduced physical performance. To determine the effect of chest expansion resistance exercise and respiratory muscle stretching on respiratory function and gait endurance in patients with stroke. Thirty stroke patients were randomly assigned to a chest expansion resistance group (CERG), a respiratory muscle stretching group (RMSG), and a control group (CG). CERG and RMSG received chest expansion resistance and respiratory muscle stretching, respectively, 3 times a week for 8 weeks. Respiratory function, respiratory muscle strength, and gait endurance were measured before and after the intervention period. The experimental groups, CERG and RMSG, showed significant improvements in respiratory function variables (p < .05). For respiratory muscle strength variables, maximal inspiratory pressure (MIP) in the CERG and maximal expiratory pressure (MEP) in the RMSG showed significant changes compared to the CG (p < .05). Both CERG and RMSG also showed significant improvements in the 6MWT compared to the CG (p < .05). Chest expansion resistance exercise would be a more effective method, while both chest expansion resistance exercise and respiratory muscle stretching are helpful in improving respiratory function and gait endurance.