continuous variables
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Bagus Haryadi ◽  
Po-Hao Chang ◽  
Akrom Akrom ◽  
Arifan Q. Raharjo ◽  
Galih Prakoso

<span>An analysis of blood circulation was used to identify variations of heart rate and to create an early warning system of autonomic dysfunction. The Poincaré plot analyzed blood circulation using photoplethysmography (PPG) signals between non-smokers and smokers in three different indices: SD1, SD2, and SD1 SD2 ratio (SSR). There were twenty subjects separated into non-smoker and smoker groups with sample sizes of 10, respectively. An independent sample t-test to compare the continuous variables. Whereas, the comparison between two groups employed Fisher’s exact test for categorical variables. The result showed that SD1 was found to be considerably lower in the group of smokers (0.03±0.01) than that of the non-smokers (0.06±0.03). Similarly, SSR was recorded at 0.0012±0.0005 and 0.0023±0.0012 for smoking and non-smoking subjects, respectively. As a comparison, SD2 for non-smokers (25.7±0.5) was lower than smokers (27.3±0.4). In conclusion, we revealed that the parameters of Poincaré plots (SD1, SD2, and SSR) exert good performances to significantly differentiate the PPG signals of the group of non-smokers from those of smokers. We also supposed that the method promises to be a suitable method to distinguish the cardiovascular disease group. Therefore, this method can be applied as a part of early detection system of cardiovascular diseases.</span>

2022 ◽  
Vol 32 (1) ◽  
pp. 1-27
Damian Vicino ◽  
Gabriel A. Wainer ◽  
Olivier Dalle

Uncertainty Propagation methods are well-established when used in modeling and simulation formalisms like differential equations. Nevertheless, until now there are no methods for Discrete-Dynamic Systems. Uncertainty-Aware Discrete-Event System Specification (UA-DEVS) is a formalism for modeling Discrete-Event Dynamic Systems that include uncertainty quantification in messages, states, and event times. UA-DEVS models provide a theoretical framework to describe the models’ uncertainty and their properties. As UA-DEVS models can include continuous variables and non-computable functions, their simulation could be non-computable. For this reason, we also introduce Interval-Approximated Discrete-Event System Specification (IA-DEVS), a formalism that approximates UA-DEVS models using a set of order and bounding functions to obtain a computable model. The computable model approximation produces a tree of all trajectories that can be traversed from the original model and some erroneous ones introduced by the approximation process. We also introduce abstract simulation algorithms for IA-DEVS, present a case study of UA-DEVS, its IA-DEVS approximation and, its simulation results using the algorithms defined.

2022 ◽  
Vol 12 (1) ◽  
pp. 105
Ren-Long Jan ◽  
Chung-Han Ho ◽  
Jhi-Joung Wang ◽  
Sung-Huei Tseng ◽  
Yuh-Shin Chang

This nationwide, population-based, retrospective, matched case–control study included 111,960 newly diagnosed patients with scleritis who were identified by the International Classification of Diseases, Ninth Revision, Clinical Modification code 379.0, selected from the Taiwan National Health Insurance Research Database. Demographic characteristics, Sjögren syndrome, and comorbid conditions within 1 year before the scleritis diagnosis were examined using univariate logistic regression analyses, and a paired t-test was used for continuous variables. Adjusted logistic regression was used to compare the prognosis odds ratio (OR) of the patients with scleritis with the controls. After adjustment for confounders, patients with Sjögren syndrome were remarkably more likely to have scleritis than the controls (OR = 33.53, 95% confidence interval (CI) = 27.43–40.97, p < 0.001). Other conditions found to have increased odds of scleritis included post ocular pterygium, glaucoma, and scleral surgery (OR  =  4.01, 95% CI  =  3.64–4.43; OR  =  3.16, 95% CI  =  2.24–4.47; OR  =  6.83, 95% CI  =  5.34–8.74, respectively); systemic infections, such as syphilis, tuberculosis, and a human herpes viral infection (OR  =  4.01, 95% CI  =  2.93–5.50; OR  =  2.24, 95% CI  =  1.94–2.58; OR  =  8.54, 95% CI  =  8.07–9.03, respectively); and systemic diseases, such as rheumatoid arthritis, granulomatous vasculitis, systemic lupus erythematosus, ankylosing spondylitis, and gout (OR  =  2.93, 95% CI  =  2.66–3.23; OR  =  7.37, 95% CI  =  3.91–13.88; OR  =  3.18, 95% CI  =  2.63–3.85; OR  =  5.57, 95% CI  =  4.99–6.22; OR  =  2.84, 95% CI  =  2.72–2.96, respectively). The results strongly support an association between Sjögren syndrome, post ocular surgery, systemic infection disease, systemic autoimmune disease, and scleritis.

2022 ◽  
Vol 12 (1) ◽  
Kai-bao Ji ◽  
Zhe Hu ◽  
Qing-lin Zhang ◽  
Hai-feng Mei ◽  
Yi-qiao Xing

AbstractThis meta-analysis aimed to analyze retinal microvasculature features in eyes with Behçet’s disease (BD) using optical coherence tomography angiography (OCTA). Electronic databases, including PubMed, Web of Science, Embase, and Cochrane Library, were comprehensively searched for published studies comparing retinal microvasculature characteristics between eyes with BD and controls. Continuous variables were calculated using the mean difference (MD) with 95% confidence interval (CI). Review Manager software (version 5.30) was used to conduct statistical analysis. A total of 13 eligible studies involving 599 eyes with BD and 622 control eyes were included in the meta-analysis. The pooled results showed that the macular whole enface superficial and deep vessel density (VD) values measured by OCTA were significantly lower in eyes with BD than in control eyes (superficial VD: MD = − 3.05, P < 0.00001; deep VD: MD = − 4.05, P = 0.0004). The foveal superficial and deep VD values were also significantly lower in the BD group than in the control group (superficial VD: MD = − 1.50, P = 0.009; deep VD: MD = − 4.25, −  = 0.03). Similarly, the analysis revealed a significant reduction in the parafoveal superficial and deep VD in eyes with BD than in control eyes (superficial VD: MD =  − 3.68, P < 0.00001; deep VD: MD = − 4.95, P = 0.0007). In addition, the superficial and deep foveal avascular zones (FAZs) were significantly larger in patients with BD than in controls (superficial FAZ: MD = 0.06, P = 0.02; deep FAZ: MD = 0.12, P = 0.03). The present meta-analysis found that macular whole enface VD, foveal VD, and parafoveal VD were lower in eyes with BD, and the FAZ was larger in patients with BD. The findings suggest that OCTA can assist clinicians in diagnosing and monitoring the status of patients with BD.

2022 ◽  
Vol 12 ◽  
Jianping Bi ◽  
Jing Qian ◽  
Dongqin Yang ◽  
Lu Sun ◽  
Shouyu Lin ◽  

PurposeDosimetric parameters (e.g., mean lung dose (MLD), V20, and V5) can predict radiation pneumonitis (RP). Constraints thereof were formulated before the era of combined immune checkpoint inhibitors (ICIs) and radiotherapy, which could amplify the RP risk. Dosimetric predictors of acute RP (aRP) in the context of ICIs are urgently needed because no data exist thus far.Methods and MaterialsAll included patients underwent thoracic intensity-modulated radiotherapy, previously received ICIs, and followed-up at least once. Logistic regression models examined predictors of aRP (including a priori evaluation of MLD, V20, and V5), and their discriminative capacity was assessed by receiver operating characteristic analysis.ResultsMedian follow-up of the 40 patients was 5.3 months. Cancers were lung (80%) or esophageal (20%). ICIs were PD-1 (85%) or PD-L1 (15%) inhibitors (median 4 cycles). Patients underwent definitive (n=19), consolidative (n=14), or palliative (n=7) radiotherapy; the median equivalent dose in 2 Gy fractions (EQD2) was 60 Gy (IQR, 51.8-64 Gy). Grades 1-5 aRP occurred in 25%, 17.5%, 15%, 2.5%, and 5%, respectively. The only variables associated with any-grade aRP were V20 (p=0.014) and MLD (p=0.026), and only V20 with grade ≥2 aRP (p=0.035). Neither the number of prior ICI cycles nor the delivery of concurrent systemic therapy significantly associated with aRP risk. Graphs were constructed showing the incrementally increasing risk of aRP based on V20 and MLD (continuous variables).ConclusionsThis is the first study illustrating that V20 and MLD may impact aRP in the setting of prior ICIs. However, these data should not be extrapolated to patients without pre-radiotherapy receipt of prior ICIs, or to evaluate the risk of chronic pulmonary effects. If these results are validated by larger studies with more homogeneous populations, the commonly accepted V20/MLD dose constraints could require revision if utilized in the setting of ICIs.

Jannik Burre ◽  
Dominik Bongartz ◽  
Alexander Mitsos

AbstractSuperstructure optimization is a powerful but computationally demanding task that can be used to select the optimal structure among many alternatives within a single optimization. In chemical engineering, such problems naturally arise in process design, where different process alternatives need to be considered simultaneously to minimize a specific objective function (e.g., production costs or global warming impact). Conventionally, superstructure optimization problems are either formulated with the Big-M or the Convex Hull reformulation approach. However, for problems containing nonconvex functions, it is not clear whether these yield the most computationally efficient formulations. We therefore compare the conventional problem formulations with less common ones (using equilibrium constraints, step functions, or multiplications of binary and continuous variables to model disjunctions) using three case studies. First, a minimalist superstructure optimization problem is used to derive conjectures about their computational performance. These conjectures are then further investigated by two more complex literature benchmarks. Our analysis shows that the less common approaches tend to result in a smaller problem size, while keeping relaxations comparably tight—despite the introduction of additional nonconvexities. For the considered case studies, we demonstrate that all reformulation approaches can further benefit from eliminating optimization variables by a reduced-space formulation. For superstructure optimization problems containing nonconvex functions, we therefore encourage to also consider problem formulations that introduce additional nonconvexities but reduce the number of optimization variables.

Critical Care ◽  
2022 ◽  
Vol 26 (1) ◽  
Yunjoo Im ◽  
Danbee Kang ◽  
Ryoung-Eun Ko ◽  
Yeon Joo Lee ◽  
Sung Yoon Lim ◽  

Abstract Background Timely administration of antibiotics is one of the most important interventions in reducing mortality in sepsis. However, administering antibiotics within a strict time threshold in all patients suspected with sepsis will require huge amount of effort and resources and may increase the risk of unintentional exposure to broad-spectrum antibiotics in patients without infection with its consequences. Thus, controversy still exists on whether clinicians should target different time-to-antibiotics thresholds for patients with sepsis versus septic shock. Methods This study analyzed prospectively collected data from an ongoing multicenter cohort of patients with sepsis identified in the emergency department. Adjusted odds ratios (ORs) were compared for in-hospital mortality of patients who had received antibiotics within 1 h to that of those who did not. Spline regression models were used to assess the association of time-to-antibiotics as continuous variables and increasing risk of in-hospital mortality. The differences in the association between time-to-antibiotics and in-hospital mortality were assessed according to the presence of septic shock. Results Overall, 3035 patients were included in the analysis. Among them, 601 (19.8%) presented with septic shock, and 774 (25.5%) died. The adjusted OR for in-hospital mortality of patients whose time-to-antibiotics was within 1 h was 0.78 (95% confidence interval [CI] 0.61–0.99; p = 0.046). The adjusted OR for in-hospital mortality was 0.66 (95% CI 0.44–0.99; p = 0.049) and statistically significant in patients with septic shock, whereas it was 0.85 (95% CI 0.64–1.15; p = 0.300) in patients with sepsis but without shock. Among patients who received antibiotics within 3 h, those with septic shock showed 35% (p = 0.042) increased risk of mortality for every 1-h delay in antibiotics, but no such trend was observed in patients without shock. Conclusion Timely administration of antibiotics improved outcomes in patients with septic shock; however, the association between early antibiotic administration and outcome was not as clear in patients with sepsis without shock.

2022 ◽  
Vol 11 ◽  
pp. 295-300
Xin Xiong ◽  
Qinlanhui Zhang ◽  
Yang Liu

Objectives: The objective of the study is to determine the relationships between ramus height and occlusal planes (OPs) in Han Chinese individuals with normal occlusion. Materials and Methods: Two hundred and four participants with normal occlusion were included and their cephalograms were analyzed. The ramus height (Ar-Go), Frankfort horizontal plane-posterior OP (FH-POP), FH-anterior OP (FH-AOP) and FH-OP, anterior and posterior cranial base length, SNA, SNB, ANB, Frankfort-mandibular plane angle, SN-MP, jaw angle, and mandibular body length were measured on the subjects’ cephalograms. Pearson correlation coefficients were calculated among continuous variables. The ramus height was considered as dependent variable and the OPs as independent variables. Age, sex, and other cephalometric parameters were considered as possible confounding factors. Univariate and multivariate analyses were performed to determine whether the relationships were significant. Results: The FH-POP and FH-OP were moderately associated with ramus height, while the FH-AOP showed a weak association (P < 0.001). After adjusting age and sex, FH-POP, FH-AOP, and FH-OP showed significant negative associations with ramus height (β = −0.36, −0.28, and −0.37, respectively, P < 0.001). The OP flattened with the ramus height increased. After adjusting all the confounding factors, FH-POP and FH-OP showed significant negative associations with ramus height. The ramus height increased by 0.19 mm/1° flattening of FHPOP (β = −0.19, P = 0.002). Conclusion: After adjust age, sex, and other possible confounding factors, the FH-POP and FH-OP were associated with the ramus height. The flattening of FH-POP was associated with the increase of ramus height. The results should be treated with caution since it’s a cross-sectional study.

2022 ◽  
pp. 112972982110673
Srinidhi Shanmugasundaram ◽  
Aleksander Kubiak ◽  
Aleena Dar ◽  
Abhishek Shrinet ◽  
Nirav Chauhan ◽  

Purpose: To evaluate the incidence of large bore hemodialysis catheter malfunction in the setting of COVID-19. Materials and methods: A retrospective review was performed of all patients who underwent placement of a temporary hemodialysis catheter after developing kidney injury after COVID-19 infection at our institution. Data collected included demographic information, procedure related information, and incidence of replacement due to lumen thrombosis. Groups were compared using students t-test for continuous variables and Fisher’s exact test for nominal variables. Results: Sixty-four patients (43M, mean age 63.2 ± 13.3) underwent placement of temporary hemodialysis catheter placement for kidney injury related to COVID 19 infection. Thirty-one (48.4%) of catheters were placed via an internal jugular vein (IJV) access and 33 (52.6%) of catheters were placed via a common femoral vein (CFV) access. Overall, 15 (23.4%) catheters required replacement due to catheter dysfunction. There were no differences in demographics in patients who required replacement to those who did not ( p > 0.05). Of the replacements, 5/31 (16%) were placed via an IJV access and 10/33 (30.3%) were placed via a CFV access ( p = 0.18). The average time to malfunction/replacement was 7.8 ± 4.8 days for catheters placed via an IJ access versus 3.4 ± 3.3 days for catheters placed via a CFV access ( p = 0.055). Conclusion: A high incidence of temporary dialysis catheter lumen dysfunction was present in patients with COVID-19 infection. Catheters placed via a femoral vein access had more frequent dysfunction with shorter indwelling time.

2022 ◽  
Vol 22 (1) ◽  
Elizabeth Kasagama ◽  
Jim Todd ◽  
Jenny Renju

Abstract Background Antenatal care (ANC) is crucial for the health of the mother and unborn child as it delivers highly effective health interventions that can prevent maternal and newborn morbidity and mortality. In 2002, the World Health Organization (WHO) recommended a minimum of four ANC visits for a pregnant woman with a positive pregnancy during the entire gestational period. Tanzania has sub-optimal adequate (four or more) ANC visits, and the trend has been fluctuating over time. An understanding of the factors that have been contributing to the fluctuating trend over years is pivotal in increasing the proportions of pregnant women attaining adequate ANC visits in Tanzania. Methods The study used secondary data from Tanzania Demographic Health Survey (TDHS) from 2004 to 2016. The study included 17976 women aged 15-49 years. Data were analyzed using Stata version 14. Categorical and continuous variables were summarized using descriptive statistics and weighted proportions. A Poisson regression analysis was done to determine factors associated with adequate ANC visits. To determine factors associated with changes in adequate ANC visits among pregnant women in Tanzania from 2004 to 2016, multivariable Poisson decomposition analysis was done. Results The overall proportion of women who had adequate ANC visits in 2004/05, 2010 and 2015/16 was 62, 43 and 51% respectively. The increase in the proportion of women attaining adequate ANC from 2010 to 2015/16 was mainly, 66.2% due to changes in population structure, thus an improvement in health behavior. While 33.8% was due to changes in the mother’s characteristics. Early initiation of first ANC visit had contributed 51% of the overall changes in adequate ANC attendance in TDHS 2015/16 survey. Conclusion Early ANC initiation has greatly contributed to the increased proportion of pregnant women who attain four or more ANC visits overtime. Interventions on initiating the first ANC visit within the first twelve weeks of pregnancy should be a priority to increase proportion of women with adequate ANC visit.

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