Multivariate Sensitivity Analyses Research Articles

Letrozole + Ziwu Liuzhu Transcutaneous Electrical Acupoint Stimulation Improves Ovulation-Induced Pregnancy Rate in Obese Women with Polycystic Ovary Syndrome: A Prospective Cohort Study.

This study investigated the effect of letrozole with/without meridian-infusion percutaneous electrical stimulation on the rates of ovulation-induced pregnancy in patients with obese polycystic ovary syndrome (obPCOS). Patients with obPCOS, ages 20-40, each with a body mass index (BMI) ≥24 kg/m2, and/or waist circumference ≥80 cm, and at least 1 side tubal patency were enrolled at the Guangdong Women and Children Hospital, Guangzhou, China. They were divided into 2 groups: ZLT [Ziwu Liuzhu + transcutaneous electrical acupoint stimulation] and control. Baseline conditions and pregnancy status were collected for all patients. Multivariate Cox regression analysis and sensitivity analysis of propensity score matching (PSM) were performed for the groups after multiple interpolations. From July 2021 to September 2022, 345 patients with obPCOS were recruited: 53 cases/69 cycles in the ZLT group and 292 cases/396 cycles in the control group. The 2 sets of baselines were flush. The anovulatory cycle rates were: ZLT, 2.89% (2/69); and control, 1.77% (7/396); P > 0.05. Multifollicle growth-cycle rates were: ZLT, 0% (0/69); and control, 0.76% (3/396); P > 0.05. Multivariate COX regression analysis showed adjusted hazard ratio (aHR) 95% confidence interval (CI): 2.11 (1.19, 3.73); P = 0.011. Multivariate Cox regression analysis with multiple imputation showed aHR 95% CI: 2.11 (1.19, 3.73); P = 0.013. In the overweight group (24-28 kg/m2), the pregnancy rate of the control and ZLT groups were 20.2% and 32.3%, respectively, aHR 95% CI: 1.76 (0.87,3.55); P = 0.113. In the obese cohort (≥ 28 kg/m2), the control and ZLT groups, pregnancy rates were 10.7% and 27.3%, respectively, aHR 95% CI: 3.46 (1.21, 9.92); P = 0.021; (Pfor interaction = 0.369). The caliper value was set as 0.2 for BMI and antral-follicle count, and PSM was performed at 1:1, aHR 95%CI: 2.45 (1.01, 5.96); P = 0.048. Letrazole + ZLT had a positive effect on ovulation-induced pregnancy rates in patients with obPCOS.

Poor sleep is associated with energy drinks consumption among Korean adolescents.

A growing number of Korean adolescents consume energy drinks, which may increase the risk of obesity, anxiety and insomnia. We examined whether poor sleep was associated with energy drink consumption among study participants. We used a cross-sectional design. The Korea Youth Risk Behavior Web-Based Survey data from 2019. To determine the association between sleep and energy drink consumption, we compared the independent variables for 50,455 adolescents in Korea (aged 14-19 years) using multivariate logistic regression and sensitivity analyses. In Korea, 69·5 % adolescents consumed energy drinks, 17·1 % slept for less than 5 h, 22·4 % slept for 5-6 h, 23·8 % slept for 6-7 h, 19·9 % slept for 7-8 h and 16·7 % slept for 8 h or more. Regarding sleep satisfaction, 21·0 % reported sufficient, 32·6 % reported just enough and 46·5 % reported insufficient. Regarding sleep duration, it was found that less than 5 h (OR, 2·36; 95 % CI (2·14, 2·60)) and lower sleep satisfaction (OR, 1·12; 95 % CI (1·03, 1·21)) were highly associated with energy drink consumption, with statistical significance at P < 0·05. Adolescents with lower sleep duration (adjusted OR (aOR), 6·37; 95 % CI (4·72, 8·61)) and a lack of sleep satisfaction (aOR, 1·44; 95 % CI (1·16, 1·78)) reported drinking a high amount of energy drinks, that is, at least once a day. In addition to efforts to decrease the amount of energy drinks consumed, sleep hygiene education needs to be strengthened.

Mathematical modeling for operative improvement of the decoloration of Acid Red 27 by a novel microbial consortium of Trametes versicolor and Pseudomonas putida: A multivariate sensitivity analysis

In this work, it is presented a first approach of a mathematical and kinetic analysis for improving the decoloration and further degradation process of an azo dye named acid red 27 (AR27), by means of a novel microbial consortium formed by the fungus Trametes versicolor and the bacterium Pseudomonas putida. A multivariate analysis was carried out by simulating scenarios with different operating conditions and developing a specific mathematical model based on kinetic equations describing all stages of the biological process, from microbial growth and substrate consuming to decoloration and degradation of intermediate compounds. Additionally, a sensitivity analysis was performed by using a factorial design and the Response Surface Method (RSM), for determining individual and interactive effects of variables like, initial glucose concentration, initial dye concentration and the moment in time for bacterial inoculation, on response variables assessed in terms of the minimum time for: full decoloration of AR27 (R1 = 2.375 days); maximum production of aromatic metabolites (R2 = 1.575 days); and full depletion of aromatic metabolites (R3 = 12.9 days). Using RSM the following conditions improved the biological process, being: an initial glucose concentration of 20 g l-1, an initial AR27 concentration of 0.2 g l-1 and an inoculation moment in time of P. putida at day 1. The mathematical model is a feasible tool for describing AR27 decoloration and its further degradation by the microbial consortium of T. versicolor and P. putida, this model will also work as a mathematical basis for designing novel bio-reaction systems than can operate with the same principle of the described consortium.

Experimental investigation of near-field spray characteristics of RP3 aviation fuel based on multivariable sensitivity and uncertainty analysis

The utilization of aviation kerosene RP3 in diesel engines and ground vehicles has attracted more attention due to the implementation of the army's Single Fuel Concept. To explore the characteristics of the RP3 near-field spray primary breakup, experimental studies were carried out via the diffuser back-illumination imaging (DBI) method under single-hole injectors accommodated to varied engine spray circumstance. The critical factors of the variability in RP3 spray characteristics response were figured out by constructing a one-dimensional active subspace to perform multivariable synergistic effects via sensitivity analysis. Moreover, the uncertainties associated with unstable cavitation within nozzle were quantified with a varied array of operating conditions. In comparison to diesel, it is indicated that, there is a range of critical cavitation, in where greater uncertainties in spray cone angles are exhibited, especially for RP3. RP3 tends to form a ‘mushroom’ spray structure, with a smaller spray cone angle compared to diesel, but the disparity gradually diminishes as the fuel injection pressure increases. The gradual transition from ‘needle’ to ‘mushroom’ shape in RP3's near-field spray structure is revealed with increased fuel injection pressure, and the appearance time of the ‘mushroom’ structure advances with higher ambient pressures. Based on the active space construction, the sensitivity analysis discovers that the spray cone angle is dominantly influenced by ambient pressure and cavitation within the nozzle, thus providing a new perspective on analyzing test data without the expense of single variable statistical work.

Low lean mass with obesity in older adults with hypertension: prevalence and association with mortality rate

BackgroundThe influence of sarcopenic obesity (SO) on overall survival in older adults with hypertension has not been addressed. The aim of this study was to investigate the prevalence and mortality predictive value of various body composition phenotypes, focusing mainly on SO, in older adults with hypertension.MethodsWe included 1105 hypertensive patients aged ≥ 60 years from the National Health and Nutrition Examination Survey 1999–2004. Sarcopenia was broadly defined based on low lean mass (LLM; as measured by dual-energy X-ray absorptiometry), and was defined using appendicular lean mass (ALM) divided by height squared (ALM/height2), weight (ALM/weight), and body mass index (BMI; ALM/BMI), respectively. Obesity was defined as BMI ≥ 30 kg/m2, body fat percentage ≥ 30/42%, or waist circumference ≥ 102/88 cm. The prevalence of LLM with obesity was estimated according to each ALM index (ALMI). Multivariable Cox regression analysis and sensitivity analysis were used to examine the association between various body composition phenotypes and all-cause mortality.ResultsIn older adults with hypertension, the prevalence of LLM with obesity by the ALM/height2 index (9.8%) was lower relative to the ALM/weight (11.7%) and ALM/BMI indexes (19.6%). After a median follow-up of 15.4 years, 642 deaths occurred. In the fully adjusted models, LLM with obesity was significantly associated with a higher risk of all-cause mortality (hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.14–2.49, P = 0.008; HR 1.48, 95% CI 1.04–2.10, P = 0.028; HR 1.30, 95% CI 1.02–1.66, P = 0.037; respectively) compared with the normal body phenotype, with no statistical differences found in individuals with LLM or obesity alone. Sensitivity analysis confirmed the robustness of the results.ConclusionsThe prevalence of LLM with obesity markedly differed in older adults with hypertension according to the 3 different ALMIs, varying from 9.8%, 11.7%, to 19.6%. Patients with both LLM and obesity had a higher risk of all-cause mortality. Further large, prospective, cohort studies are warranted to validate these findings and uncover underlying mechanisms.

'PartBreCon' study. A UK multicentre retrospective cohort study to assess outcomes following PARTial BREast reCONstruction with chest wall perforator flaps.

Partial breast reconstruction with a pedicled chest wall perforator flap (CWPF) enables breast conservation in a higher tumour: breast volume ratio scenario. Since there is limited evidence, this retrospective cohort study aimed to ascertain immediate (30-days) and medium-term (follow-up duration) surgical outcomes. STROBE-compliant protocol ascertained CWPF outcomes between March 2011-March 2021. UK centres known to perform CWPF were invited to participate if they performed at least 10 cases. Data were retrospectively collected, including patient demographics, tumour and treatment characteristics, and surgical and oncological outcomes. Statistical analysis (R™) included multivariable logistic regression and sensitivity analysis. Across 15 centres, 507 patients with median age (54 years, IQR; 48-62), body mass index (25.4kg/m2, IQR; 22.5-29), tumour size (26mm, IQR; 18-35), and specimen weight (62g, IQR; 40-92) had following flap types: LiCAP (54.1%, n=273), MiCAP/AiCAP (19.6%, n=99), LiCAP+LTAP (19.8%, n=100) and TDAP (2.2%, n=11). 30-days complication rates were in 12%: haematoma (4.3%, n=22), wound infection (4.3%, n=22), delayed wound healing (2.8%, n=14) and flap loss (0.6%, n=3; 1 full) leading to readmissions (2.6%, n=13) and re-operations (2.6%, n=13). Positive margins (n=88, 17.7%) led to 15.9% (n=79) re-excisions, including 7.5% (n=37) at the planned 2nd of 2-stage surgery and 1.8% (n=9) mastectomy. At median 23 months (IQR; 11-39) follow-up, there were 1.2% (n=6) symmetrisations; recurrences: local (1%), regional/nodal (0.6%) and distant (3.2%). This large multicentre cohort study demonstrates acceptable complication and margin re-excision rates. CWPF extends the range of breast conservation techniques. Further studies are required for long-term oncological outcomes.

Association between marijuana use and kidney stone: a cross-sectional study of NHANES 2009 to 2018.

Objective: The purpose of this investigation is to determine whether regular marijuana use is related to history of kidney stones in the US population. Methods: Data were obtained from the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018. Kidney stone and marijuana use data were collected from self-report questionnaires. Multivariate logistic regression and multiple sensitivity analyses were applied to examine the relationship between marijuana usage and kidney stones. Results: There are approximately 26.04% of the US population have admitted to using marijuana in their lifetime. Compared with none regular users, those with a higher frequency of marijuana use were more males, more non-Hispanic races, lower than high school education, overweight, no recreational activity, without diabetes mellitus, and more coronary heart disease. After adjusting for potential confounders, multivariate regression analysis demonstrated that marijuana use was inversely correlated to kidney stones in males (Odds ratio [OR] = 0.72, 95% Confidence interval [CI] = 0.54-0.97). One to seven times/week regular consumption of marijuana was associated with kidney stones in males (OR = 0.62, 95% CI = 0.43-0.89). Sensitivity analyses validated the robustness of our outcomes. Conclusion: Our findings revealed that regular marijuana male users were inversely associated with kidney stones. Marijuana use one to six times/week was inversely related to the risk of kidney stones in males. Further studies are required to explore the dose and type associations of marijuana with kidney stones.

(Invited) Techno-Economic Analysis on Near-Term and Future Projections of Levelized Cost of Hydrogen for Low-Temperature Water Electrolysis Technologies

Hydrogen is seen as a potential energy intermediary between renewable energy sources and end-use applications including transportation, power, and industrial feedstocks. Core to this approach is low-cost hydrogen generation via water electrolysis. Significant research has been undertaken to improve the electrolysis stack technology, including enhancements in electrical efficiency, materials degradation, and total stack cost. However, relative to the total cost of installing an electrolysis plant, the stack contributes <50% of the initial capital investment. Therefore, from an electrolysis project perspective, the mechanical balance of plant and electrical systems required to operate the plant are equally important to understand.To explore the near-term and future cost projection for hydrogen production via electrolysis, Strategic Analysis, Inc. (SA) has developed a bottom-up project cost model for Alkaline, Proton Exchange Membrane (PEM), and Anion Exchange Membrane (AEM) electrolysis technologies. This project cost model incorporates: 1) Stack cost, derived from a Design for Manufacturing and Assembly (DFMA) process-based cost model developed by SA, 2) mechanical balance of plant, including process equipment, piping, valves, and instrumentation, derived from equipment quotes, scaling, database values, and Aspen estimates; 3) electrical balance of plant, including wiring, rectification, and electrical infrastructure upgrades, derived from time and material cost correlations; 4) Site Preparation, focused on green field installation; and 5) Construction Overhead, including engineering, procurement, and construction (EPC) costs and project contingency. The SA project cost model is fed into a Levelized Cost of Hydrogen (LCOH) model that accounts for electricity and water consumption, in addition to other operating costs, including labor, maintenance, and stack replacements.The SA project cost model and the LCOH model were used to conceptualize electrolysis system sizes from 100 MW to 1 GW for Alkaline, PEM, and AEM electrolysis systems. From a project perspective, electricity costs contribute 50-80% to the LCOH while capital and maintenance costs contribute the remaining 20-50% to the LCOH. Improvements in stack performance and cost offer incremental improvements in LCOH; however, larger reductions in hydrogen cost will only be possible through optimization of the stack cell voltage and operating current density in conjunction with reductions in net electricity price through integration with low-cost, probably renewable, electricity.Results from SA’s polarization performance optimization model show that lower cost Alkaline stacks, having somewhat lower performance (than PEM), tend to optimize at lower current densities leading to a larger stack active area, and benefit from low operational voltage to obtain higher conversion efficiencies. Higher cost PEM stacks with higher performance (than Alkaline stacks) tend to optimize at higher current densities to reduce the size/capital cost of the stacks and can afford a lower stack efficiency. Multivariable sensitivity analyses show the statistical variation in capital cost leading to the most likely range in LCOH for each technology. The results of this study provide guidance on where the largest incremental reductions in LCOH can be achieved on a project basis.

Association between depression and tinnitus in US adults: A nationally representative sample.

Data from the National Health and Nutrition Examination Survey (NHANES) has not been previously utilized to study the prevalence of tinnitus and depression among adults over 20 years old, nor the impact of tinnitus on depression. The aim of this study was to evaluate the relationship between tinnitus and depression among adults in the United States. This cross-sectional study drew upon data from the 2005-2018 NHANES, incorporating adults aged 20 and older who had completed the tinnitus and depression questionnaire. Depression was assessed using the PHQ-9 questionnaire. Multivariate logistic regression models, subgroup analyses, and sensitivity analyses were performed to examine the association between tinnitus and depression. This nationally representative study included 10,409 participants, of whom 17.69% reported experiencing tinnitus. The prevalence of depression was 6.2% among those without tinnitus and 15.1% among those with tinnitus (p < .0001). Accounting for potential confounders such as demographic and socioeconomic variables, participants who experienced tinnitus were more likely to exhibit depression symptoms (adjusted odds ratio = 2.0, 95% confidence interval = 1.61-2.48). Subgroup analyses further suggested that tinnitus was associated with an increased prevalence of depression across all subgroups. Sensitivity analysis affirmed these findings. This study suggests that there is a significant association between tinnitus and the risk of depression in the adult population of the United States, emphasizing the importance of psychological factors in the clinical management of tinnitus. 2b.

Li-ion battery aging model robustness: An analysis using univariate and multivariate techniques

Batteries are highly flexible energy storages and they can be easily integrated in energy systems. However, the modeling of batteries must be coherent and robust to be effectively included in the energy systems; in particular, the aging phenomena are known to significantly impact the storage capacity, charging/discharging behaviors, and the state of charge. While data-driven lithium-ion battery models, which consider both cyclic and calendar aging, are widely reported in the scientific literature, their robustness in dealing with different data compared to trained ones has not been deeply investigated so far. In this study, a sensitivity analysis is performed using three aging models available in the scientific literature (e.g., Wang’s, Baghdadi’s, and Omar’s ones) to investigate their performance under different operating conditions of both temperature and current. Results of both univariate and multivariate sensitivity analyses refer to a 160 A h battery, showing that all the three models are able to accurately predict the battery aging under different operating conditions, but some of these models are more sensitive to specific factors than others. Specifically, the multivariate analysis shows that Wang’s model is the most robust one in the face of simultaneous changes in both temperature and current.

The Effect of Computer Tablets on the Need for Medical Anxiolysis in Children in an Ambulatory Surgical Center.

Background Preoperative anxiety is common in children undergoing surgery. When anxiety is identified or suspected, there are several strategies typically used to manage it. Perhaps the most common is anxiolytic premedication or parental presence at induction. Medications such as midazolam have been associated with adverse effects, such as a slower wakeup, and require timing of administration, while parental presence can be disturbing to the parent and divert the attention of the operating room team. A more recent option is distraction via electronic tablets. The purpose of this study was to retrospectively investigate and quantify any change in the use of midazolam, the most common anxiolytic approach at our institution, and any change in the length of time in the post-anesthesia care unit (PACU) following the introduction of tablet computers to a pediatric ambulatory surgical center. Methods We conducted an IRB-approved retrospective chart review of 13,790 pediatric patients ages one to 18 undergoing outpatient elective surgeries at the University of Florida (UF) Children's Surgical Center over a five-year period. A univariate analysis was conducted using the Fisher's Exact test and interrupted time series analysis to determine differences between midazolam administration and PACU times, with interruption occurring at tablet implementation. A multivariable analysis and sensitivity analyses were performed to confirm the findings of the univariate analysis. Results On univariate analysis, tablet availability was associated with both a decreased preoperative oral midazolam administration (odds ratio (OR) 0.158, 95% confidence interval (CI): 0.140 to 0.179, P-value <0.001) and a decreased PACU length of stay (-17.4 min, 95% CI: -19.6 to -15.3 min, P-value <0.001). The association with decreased preoperative midazolam administration held after multivariable analysis (adjusted OR 0.207, 95% CI: 0.154 to 0.278, P-value <0.001), but PACU length of stay was not statistically significant (-9.1 min, 95% CI: -20.6 to 2.4, P-value = 0.12). These results were confirmed on sensitivity analysis, with tablet availability continuing to be associated with decreased preoperative oral midazolam administration but not with reduced PACU length of stay. Conclusion Our results demonstrate that computer tablets were associated with a significant decrease in the frequency of midazolam administration and consequently may reduce preoperative pediatric anxiety.We did not find an associated change in PACU length of stay following the introduction of tablets. Tablets present a unique distraction alternative to chemical anxiolysis for institutions seeking to reduce medication use in pediatric patients.

Cost analysis and economic evaluation of a virtual pediatric emergency department pilot program.

The Children's Hospital of Eastern Ontario launched Canada's first virtual pediatric emergency department (ED) from May 2020 through November 2021 to deliver accessible care during the COVID-19 pandemic. The objective of this study was to (i) conduct a cost analysis of the virtual pediatric ED, and (ii) compare the virtual costs to in-person ED costs to inform future resource allocation decisions. We calculated costs from a health system perspective in 2021 Canadian dollars. Using a decision tree model, we compared expected costs with and without the virtual pediatric ED, and calculated overall and per patient cost savings of implementing the virtual ED. The virtual ED provided care to 7394 patients. In the base case, virtual care saved $890,000 ($120 per patient). One-way sensitivity analyses suggest overall cost savings were most sensitive to the proportion of virtual care patients who would have received in-person care had the virtual option not been available (range $300,000-$1,700,000), followed by ED overhead costs (range $640,000-$1,140,000). Multivariate sensitivity analyses demonstrated robust cost savings of $920,000 (95% CI 850,000-990,000) in a scenario using billing codes to calculate costs, and savings of $1,040,000 (95% CI 960,000-1,120,000) if physician salaries were used instead. These findings suggest the virtual pediatric ED reduced costs per patient. Virtual care may represent a financially valuable pediatric emergency department service.

The economic value of personal protective equipment for healthcare workers.

In this paper, we examine the cost effectiveness of investment in personal protective equipment (PPE) for protecting health care workers (HCWs) against two infectious diseases: Ebola virus and methicillin-resistant Staphylococcus aureus (MRSA). This builds on similar work published for COVID-19 in 2020. We developed two separate decision-analytic models using a payer perspective to compare the costs and effects of multiple PPE use scenarios for protection of HCW against Ebola and MRSA. Bayesian multivariate sensitivity analyses were used to consider the uncertainty surrounding all key parameters for both diseases. We estimate the cost to provide adequate PPE for a HCW encounter with an Ebola patient is $13.04, which is associated with a 97% risk reduction in infections. The mean incremental cost-effectiveness ratio (ICER) is $3.98 per disability-adjusted life year (DALY) averted. Because of lowered infection and disability rates, this investment is estimated to save $132.27 in averted health systems costs, a financial ROI of 1,014%. For MRSA, the cost of adequate PPE for one HCW encounter is $0.88, which is associated with a 53% risk reduction in infections. The mean ICER is $362.14 per DALY averted. This investment is estimated to save $20.18 in averted health systems costs, a financial ROI of 2,294%. In terms of total health savings per death averted, investing in adequate PPE is the dominant strategy for Ebola and MRSA, suggesting that it is both more costly and less clinically optimal to not fully invest in PPE for these diseases. There are many compelling reasons to invest in PPE to protect HCWs. This analysis examines the economic case, building on previous evidence that protecting HCWs with PPE is cost-effective for COVD-19. Ebola and MRSA scenarios were selected to allow assessment of both endemic and epidemic infectious diseases. While PPE is cost-effective for both conditions, compared to our analysis for COVID-19, PPE is relatively more cost-effective for Ebola and relatively less so for MRSA. Further research is needed to assess shortfalls in the PPE supply chain identified during the COVID-19 pandemic to ensure an efficient and resilient supply in the face of future pandemics.

Preventing eviction during pregnancy: a cost-effectiveness analysis of a theoretical safety-net program

Eviction in pregnancy has been shown to be associated with adverse birth outcomes. A safety net program focused on covering the costs of rent during pregnancy may aid in preventing adverse complications. To evaluate the cost-effectiveness of a program covering the cost of rent to prevent eviction during pregnancy. A cost-effectiveness model using TreeAge software was designed to evaluate the cost, effectiveness, and incremental cost-effectiveness ratio (ICER) associated with eviction compared to no eviction in pregnancy. The cost of eviction from a societal perspective was compared to the annual cost of housing in the no eviction group, which was estimated by the median contract rent in the US from 2021 national census data. Birth outcomes included pre-term birth, neonatal death, and major neurodevelopmental delay. Probabilities and costs were derived from the literature. The cost-effectiveness threshold was set at $100,000/QALY. We performed univariable and multivariable sensitivity analyses to assess the robustness of the results. In our theoretical cohort of 30,000 pregnant individuals aged 15-44 facing eviction annually, the no eviction during pregnancy strategy was associated with 1,427 fewer pre-term births, 47 fewer neonatal deaths, and 44 fewer cases of neurodevelopmental delay compared to eviction. At the median cost of rent in the US, the no eviction strategy was associated increased QALYs and decreased costs. Therefore, the no eviction strategy was the dominant strategy. In univariate sensitivity analysis varying the cost of housing, no eviction remained the cost-effective strategy and was cost-saving when rent was below $1,016 per month. The no eviction strategy is cost-effective and reduces cases of preterm birth, neonatal death, and neurodevelopmental delay. When rent is below the median of $1,016 per month, no eviction is the cost-saving strategy. These findings suggest that policies supporting social programmatic implementation for rent coverage for pregnant people at risk of eviction have the potential to be highly beneficial in reducing costs and disparities in perinatal outcomes.

Algorithms for perturbative analysis and simulation of quantum dynamics

We develop general purpose algorithms for computing and utilizing both the Dyson series and Magnus expansion, with the goal of facilitating numerical perturbative studies of quantum dynamics. To enable broad applications to models with multiple parameters, we phrase our algorithms in terms of multivariable sensitivity analysis, for either the solution or the time-averaged generator of the evolution over a fixed time-interval. These tools simultaneously compute a collection of terms up to arbitrary order, and are general in the sense that the model can depend on the parameters in an arbitrary time-dependent way. We implement the algorithms in the open source software package Qiskit Dynamics, utilizing the JAX array library to enable just-in-time compilation, automatic differentiation, and GPU execution of all computations. Using a model of a single transmon, we demonstrate how to use these tools to approximate fidelity in a region of model parameter space, as well as construct perturbative robust control objectives.We also derive and implement Dyson and Magnus-based variations of the recently introduced Dysolve algorithm [Shillito et al., Physical Review Research, 3(3):033266] for simulating linear matrix differential equations. We show how the pre-computation step can be phrased as a multivariable expansion computation problem with fewer terms than in the original method. When simulating a two-transmon entangling gate on a GPU, we find the Dyson and Magnus-based solvers provide a speedup over traditional ODE solvers, ranging from roughly 2× to 4× for a solution and 10× to 60× for a gradient, depending on solution accuracy.

Multivariate sensitivity analysis for a large-scale climate impact and adaptation model

Abstract We apply a new efficient methodology for Bayesian global sensitivity analysis for large-scale multivariate data. A multivariate Gaussian process is used as a surrogate model to replace the expensive computer model. To improve the computational efficiency and performance of the model, compactly supported correlation functions are used. The goal is to generate sparse matrices, which give crucial advantages when dealing with large data sets. The method was applied to multivariate data from the IMPRESSIONS Integrated Assessment Platform version 2. Our empirical results on Integrated Assessment Platform version 2 data show that the proposed methods are efficient and accurate for global sensitivity analysis of complex models.

Real-world patient-level cost-effectiveness analysis of omalizumab in patients with severe allergic asthma treated in four major medical centers in Turkey

AimsTo evaluate the cost-effectiveness of standard-of-care treatment (SoC) to SoC in combination with omalizumab (OML + Soc) in patients with severe asthma using real-world prospective clinical data from four major medical centers in Turkey.Materials and methodsBetween February 2018 and November 2019, a total of 206 patients with severe asthma, including 126 of whom were in the OML + SoC group and 80 in the SoC group, were followed for 12 months to evaluate their asthma status and quality of life. Cost data for this patient-level economic evaluation were sourced from the MEDULA database of the hospitals and expressed in Turkish Lira (₺). Efficacy data were obtained by means of Turkish versions of the Asthma Control Test for asthma status, the 5-level EQ-5D-5L version (EQ-5D-5L), and the Asthma Quality of Life Scale for quality of life. A Markov model with 2-week cycles was specified, comparing costs and treatment effects of SoC vs. OML + SoC over a lifetime from the Turkish payer perspective.ResultsPer-patient costs were ₺23,607.08 in the SoC arm and ₺425,329.81 in the OML + Soc arm, for a difference of ₺401,722.74. Life years (LY) and quality-adjusted life years (QALY) were 13.60 and 10.08, respectively, in the SoC group; and 21.26 and 13.35, respectively, in the OML + SoC group, for differences of 7.66 LYs and 3.27 QALYs. This yielded an incremental cost-effectiveness ratio of an additional ₺52,427.04 to gain 1 LY and an incremental cost-utility ratio of an incremental ₺122,675.57 to gain 1 QALY; the latter being below the ₺156,948 willingness-to-pay threshold for Turkey referenced by WHO. One-way and multivariate sensitivity analyses confirmed the base-case results.ConclusionWhereas most economic evaluations are based on aggregate data, this independent cost-effectiveness analysis using prospective real-world patient-level data suggests that omalizumab in combination with standard of care is cost-effective for severe asthma from the Turkish public payer perspective.

The association between oxidative balance score and periodontitis in adults: a population-based study.

The pathogenesis between oxidative stress and periodontitis was correlated. The Oxidative Balance Score (OBS) is a systematic tool to assess the effects of diet and lifestyle in relation to oxidative stress. However, the association between OBS and periodontitis has not been reported previously. Sixteen dietary factors and four lifestyle factors were selected to score the OBS. Multivariate logistic regression and sensitivity analysis were used to investigate the relationship between OBS and periodontitis based on data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Subgroup analysis and interaction tests were used to investigate whether this association was stable across populations. This study included 3,706 participants. There was a negative linear association between OBS and periodontitis in all participants [0.89 (0.80, 0.97)], and after converting OBS to a quartile variable, participants with OBS in the highest quartile had a 29% lower risk of periodontitis than those with OBS in the lowest quartile [0.71 (0.42, 0.98)]. This negative association differed with respect to age and diabetes. There is a negative association between OBS and periodontitis in US adults. Our results suggest that OBS may be used as a biomarker for measuring periodontitis.

Association between body mass index and reversion to normoglycemia from impaired fasting glucose among Chinese adults: a 5-year cohort study.

Evidence regarding the relationship between body mass index (BMI) and reversion to normoglycemia from prediabetes is still limited. The purpose of our study is to survey the link of BMI on reversion to normoglycemia among patients with impaired fasting glucose (IFG). This study, a retrospective cohort, covered 32 regions and 11 cities in China and collected 258,74 IFG patients who underwent a health check from 2010 to 2016. We investigated the association between baseline BMI and reversion to normoglycemia in patients with IFG using the Cox proportional-hazards regression model. The nonlinear relationship between BMI and reversion to normoglycemia was determined using a Cox proportional hazards regression with cubic spline functions and smooth curve fitting. In addition, we also performed a series of sensitivity analyses and subgroup analyses. A competing risk multivariate Cox regression was performed using progression to diabetes as a competing risk for reversal of normoglycemic events. After adjusting covariates, the results showed that BMI was negatively related to the probability of reversion to normoglycemia (HR=0.977, 95%CI:0.971-0.984). Compared with participants with normal BMI(<24kg/m2), overweight (BMI:24-28kg/m2) participants with IFG had a 9.9% lower probability of returning to normoglycemia (HR=0.901,95%CI:0.863-0.939), while obese patients (BMI ≥ 28kg/m2) had a 16.9% decreased probability of reverting from IFG to normoglycemia (HR=0.831,95%CI:0.780-0.886). There was also a nonlinear relationship between them, and the inflection point of BMI was 21.7kg/m2. The effect sizes (HR) on the left sides of the inflection point were 0.972(95%CI:0.964-0.980). The competing risks multivariate Cox's regression and sensitivity analysis demonstrated the robustness of our results. This study demonstrates a negative and nonlinear relationship between BMI and reversion to normoglycemia in Chinese patients with IFG. Minimizing BMI to 21.7 kg/m2 in patients with IFG through aggressive intervention may significantly increase the probability of returning to normoglycemia.

Female corporate leadership, institutions and financing constraints around the world

PurposeThis study aims to analyze the effect of female top management and female dominant owner on whether firms experience obstacles to obtaining external finance in 136 medium- and low-income countries during 2006–2019. The analysis controls for the role of corporate governance and other firm-specific characteristics, as well as for the impact of national institutions.Design/methodology/approachThe analysis elucidates the economic and non-economic factors driving female corporate leadership. Further, in order to capture the causal effect, the analysis uses univariate tests, multivariate regression analysis, disaggregation testing, sensitivity and endogeneity analysis to confirm the quality of the estimates. The analysis controls for various additional country-level factors.FindingsThe results show that female top management and female ownership are broadly significant determinants of firms' access to external finance, especially in relatively larger and more developed countries. The role of controlling shareholders is significant and mediates the gender effect. The latter appears more pronounced in smaller and medium-size firms, operating in the manufacturing and services sectors as well as in the countries with higher levels of development. This also varies with the countries' macroeconomic conditions and institutions governing gender development and equality as well as institutional governance effectiveness.Practical implicationsThe results suggest that firms wishing to improve the firms' access to external finance should consider the role of gender in both top management and corporate ownership coupled with the effect of the specific characteristics of firms and the conditioning role of national institutions.Originality/valueThe study examines the gender effects of top management and dominant ownership for the external financing decisions of firms in low- and middle-income countries, which are underresearched. These gender effects are mitigated in various ways by the specific characteristics of firms and especially on national institutions.