Tag: statistics

Math Biosci Eng. 2022 May 18;19(7):7284-7313. doi: 10.3934/mbe.2022344.

ABSTRACT

The vehicle routing problem (VRP) problem is a classic NP-hard problem. Usually, the traditional optimization method cannot effectively solve the VRP problem. Metaheuristic optimization algorithms have been successfully applied to solve many complex engineering optimization problems. This paper proposes a discrete Harris Hawks optimization (DHHO) algorithm to solve the shared electric vehicle scheduling (SEVS) problem considering the charging schedule. The SEVS model is a variant of the VPR problem, and the influence of the transfer function on the model is analyzed. The experimental test data are based on three randomly generated examples of different scales. The experimental results verify the effectiveness of the proposed DHHO algorithm. Furthermore, the statistical analysis results show that other transfer functions have apparent differences in the robustness and solution accuracy of the algorithm.

PMID:35730307 | DOI:10.3934/mbe.2022344

Cardiol Young. 2022 Jun 22:1-6. doi: 10.1017/S1047951122001925. Online ahead of print.

ABSTRACT

INTRODUCTION: Fetal arterial duct aneurysm, saccular, or fusiform enlargement of the arterial duct affect > 8% of pregnancies. It is uncommonly associated with serious sequelae postnatally, including thromboembolic events such as stroke and left pulmonary artery obstruction, rupture with demise, and vocal cord compression. Risk factors include maternal diabetes, late maternal age, maternal blood type A, large size for gestational age, and connective tissue disorders. The clinical importance remains unknown, making it difficult to determine how to monitor this finding postnatally.

METHODS: This is a retrospective echocardiogram study assessing the outcomes of fetally diagnosed arterial duct aneurysm. Images and records were reviewed to confirm the diagnosis and assess risk factors and outcomes. Descriptive statistics were performed.

RESULTS: Fifty-three affected fetuses were identified. The median gestational age at diagnosis was 34.9 weeks (IQR 32.6, 36.6). The median maternal age was 31 years (IQR 27.3-34.1). Eight (15%) had maternal diabetes. The most common blood type was type O. The median maximal dimension of the aneurysm was 7.6 mm (IQR 6.1, 8.7). The aortic end was the maximal dimension in 67.9%. Median postnatal follow-up period was 76 days (IQR 7.5, 368). No patients sustained postnatal demise related to the duct, rupture of the ductal aneurysm, cerebral infarction, or other sequelae. No newborn had associated connective tissue disorders. No patients underwent ductal intervention.

CONCLUSION: In our experience, no adverse outcomes related to the ductal aneurysm were identified. This should be considered when counselling families about the need for postnatal follow-up.

PMID:35730324 | DOI:10.1017/S1047951122001925

Math Biosci Eng. 2022 May 18;19(7):7272-7283. doi: 10.3934/mbe.2022343.

ABSTRACT

We study the monotonicity method to analyse nabla positivity for discrete fractional operators of Riemann-Liouville type based on exponential kernels, where $ left({}_{{c_0}}^{C{F_R}}nabla^{theta} mathtt{F}right)(t) > -epsilon, Lambda(theta-1), bigl(nabla mathtt{F}bigr)(c_{0}+1) $ such that $ bigl(nabla mathtt{F}bigr)(c_{0}+1)geq 0 $ and $ epsilon > 0 $. Next, the positivity of the fully discrete fractional operator is analyzed, and the region of the solution is presented. Further, we consider numerical simulations to validate our theory. Finally, the region of the solution and the cardinality of the region are discussed via standard plots and heat map plots. The figures confirm the region of solutions for specific values of $ epsilon $ and $ theta $.

PMID:35730306 | DOI:10.3934/mbe.2022343

Math Biosci Eng. 2022 May 12;19(7):7076-7090. doi: 10.3934/mbe.2022334.

ABSTRACT

PURPOSE: Cerebral artery fenestration is a rare vascular anomaly, but its existence has been increasingly documented. The association of cerebral infarction and fenestration is of great clinical interest, and the exact underlying mechanism remains unclear. This study aims to identify risk factors contributing to cerebral infarction by computational hemodynamics analysis.

METHODS: Eight patients with image findings of fenestration structure were recruited in this research, in which four suffered fenestration-related cerebral infarction (A series) while the other four (B series) were set as control matched by the fenestration size. Three-dimensional models were reconstructed from the MRA images and computational simulations with non-Newtonian flow model were performed to get interested hemodynamic characteristics.

RESULTS: The blood flow pattern was relatively separated along two channels of fenestration in series A compared with series B cases in Group 1-2, however, no significant difference was shown in Group 3-4. Quantitatively, planes were cut in the middle of fenestrations and the ratio of mass flow rate and area was calculated at systolic peak. Results showed that the side of the dominant blood supply was opposite between A and B series, and the dominant side was also opposite between small and large fenestrations. In infarction cases, the basilar top was distributed with larger areas of detrimental hemodynamic indicators and a larger concentrated high viscosity region.

CONCLUSION: The flow division condition throughout the fenestration structure has a key impact on further flow redistribution and flow pattern. The blood viscosity has the potential to be a useful tool in identifying the risk factors for cerebral infarction and more emphasis should be placed on the hemodynamic environment at superior cerebellar arteries.

PMID:35730297 | DOI:10.3934/mbe.2022334

Diabetol Metab Syndr. 2022 Jun 21;14(1):87. doi: 10.1186/s13098-022-00858-1.

ABSTRACT

BACKGROUND: Women with GDM have a higher risk of future cardiovascular diseases (CVD). Meanwhile, synbiotics have been demonstrated to have favorable impacts on atherogenic indices, and inflammatory and oxidative stress indicators, all of which are known to be CVD-predictive factors. The aim of this randomized controlled trial was to evaluate the effects of synbiotic supplementation on the atherogenic indices of plasma, high-sensitivity C-reactive protein (hs-CRP), and plasma malondialdehyde (MDA) in women with GDM.

METHODS: Eligible pregnant women with GDM were randomized into two groups to receive a daily synbiotic capsule [500 mg of L.acidophilus(5 × 10¹⁰ CFU/g), L.plantarum(1.5 × 10¹⁰ CFU/g), L.fermentum(7 × 10⁹ CFU/g), L.Gasseri(2 × 10¹⁰ CFU/g) and 38.5 mg of fructo-oligo-saccharides], or placebo, for 6 weeks. The ratios of TC/HDL-C, LDL/HDL-C, and logTG/HDL-C were calculated as the atherogenic indices. Serum hs-CRP and MDA concentrations were quantified before and after the intervention. Cohen’s d(d) was used to calculate the magnitude of the effect.

RESULTS: Ninety participants completed the study. There was no significant difference in dietary antioxidant and mineral intakes between the two groups. Compared with placebo, synbiotic supplementation resulted in a significant decrease in logTG/HDL-C ratio with a medium-low effect size (mean difference = -0.11; 95% CI -0.21, 0; P values for the placebo and the intervention groups were 0.02, and 0.042, respectively; P between groups = 0.003; d = 0.25). No significant changes were observed in other parameters.

CONCLUSIONS: Overall, 6 weeks of synbiotic supplementation in women with GDM resulted in a significant improvement in logTG/HDL-C, suggesting that synbiotics may have a beneficial role in reducing the risk of future CVDs associated with GDM. Nevertheless, more studies are needed to confirm the veracity of these results. Trial Registration IRCT201511183140N16 (December 29th, 2015).

PMID:35729675 | DOI:10.1186/s13098-022-00858-1

Arthritis Res Ther. 2022 Jun 21;24(1):149. doi: 10.1186/s13075-022-02812-y.

ABSTRACT

BACKGROUND: Long-term patterns of serum uric acid (SUA) and their association with the risk of myocardial infarction (MI) and mortality are poorly characterized as prior studies measured SUA at a single time point. This study aimed to identify SUA trajectories and determine their associations with incident MI and all-cause mortality.

METHODS: We included 85,503 participants who were free of MI in or prior 2012 from the Kailuan study. SUA trajectories during 2006-2012 were identified by group-based trajectory modeling. Cox proportional hazard models were used to assess the association of SUA trajectories with MI and all-cause mortality.

RESULTS: We identified three SUA trajectories during 2006-2012: low-stable (n=44,124, mean SUA: 236-249 μmol/L), moderate-stable (n=34,431, mean SUA: 324-354 μmol/L) and high-stable (n=6,984, mean SUA: 425-463 μmol/L). During a median follow-up of 6.8 years, we documented 817 (0.96%) incident MI and 6498 (7.60%) mortality. Compared with the low-stable group, high-stable group experienced a higher risk of MI (hazard ratio [HR], 1.35; 95% confidence [CI], 1.07-1.71) and all-cause mortality (HR, 1.22; 95% CI, 1.12-1.33). Multiple sensitivity analyses yielded similar results. Additionally, the association of SUA trajectory with MI and all-cause mortality was more pronounced in individuals without a history of hypertension (P-interaction=0.0359) and those aged <60 years (P-interaction<0.0001), respectively.

CONCLUSIONS: Higher SUA trajectories were associated with altered risk of MI and all-cause mortality, suggesting that monitoring SUA trajectory may assist in identifying subpopulations at higher risk of MI and all-cause mortality.

PMID:35729670 | DOI:10.1186/s13075-022-02812-y

Infect Dis Poverty. 2022 Jun 21;11(1):72. doi: 10.1186/s40249-022-01001-y.

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) epidemic, considered as the worst global public health event in nearly a century, has severely affected more than 200 countries and regions around the world. To effectively prevent and control the epidemic, researchers have widely employed dynamic models to predict and simulate the epidemic’s development, understand the spread rule, evaluate the effects of intervention measures, inform vaccination strategies, and assist in the formulation of prevention and control measures. In this review, we aimed to sort out the compartmental structures used in COVID-19 dynamic models and provide reference for the dynamic modeling for COVID-19 and other infectious diseases in the future.

MAIN TEXT: A scoping review on the compartmental structures used in modeling COVID-19 was conducted. In this scoping review, 241 research articles published before May 14, 2021 were analyzed to better understand the model types and compartmental structures used in modeling COVID-19. Three types of dynamics models were analyzed: compartment models expanded based on susceptible-exposed-infected-recovered (SEIR) model, meta-population models, and agent-based models. The expanded compartments based on SEIR model are mainly according to the COVID-19 transmission characteristics, public health interventions, and age structure. The meta-population models and the agent-based models, as a trade-off for more complex model structures, basic susceptible-exposed-infected-recovered or simply expanded compartmental structures were generally adopted.

CONCLUSION: There has been a great deal of models to understand the spread of COVID-19, and to help prevention and control strategies. Researchers build compartments according to actual situation, research objectives and complexity of models used. As the COVID-19 epidemic remains uncertain and poses a major challenge to humans, researchers still need dynamic models as the main tool to predict dynamics, evaluate intervention effects, and provide scientific evidence for the development of prevention and control strategies. The compartmental structures reviewed in this study provide guidance for future modeling for COVID-19, and also offer recommendations for the dynamic modeling of other infectious diseases.

PMID:35729655 | DOI:10.1186/s40249-022-01001-y

Stem Cell Res Ther. 2022 Jun 21;13(1):269. doi: 10.1186/s13287-022-02949-2.

ABSTRACT

BACKGROUND: Aging disturbs the skin morphology and function, manifested as thinned epithelium and impaired wound healing. As a major type of skin cells, epidermal stem cells (EpiSCs) are inevitably affected by aging. The effect of age on EpiSCs and wound healing needs to be further explored.

METHODS: Skin RNA-seq data of young (5 months) and old (30 months) CB6F1 mice were obtained from GEO Series GSE35322 with 10 in each age group. Differentially expressed genes were analyzed, and EpiSCs-related pathways were enriched by KEGG. The age-related changes of the screened PI3K/Akt pathway were validated by Western Blot and immunofluorescence of epidermis of SD rats (2, 17, and 23 months, n = 6). The expression of upstream protein EGFR was assessed by immunofluorescence in skin of mice (4, 13, and 23 months, n = 6) and human (respectively, 23, 28, 30 years old in the young group and 69, 73, 78 years old in the old group) skin. Inhibitors of EGFR were used to verify its effects on EpiSCs and wound healing. The small molecule drug Tideglusib was tested for its effects on signaling pathways of EpiSCs and wound healing of aged rats. Western Blot was used for the detection of signaling pathways in in vitro experiments. Cell migration assays were used to assess cell migration ability. Flow cytometry was used to detect changes in cell cycle and apoptosis levels. Sulforhodamine B assay and CCK-8 assay were used to evaluate cell proliferation and viability, respectively. Student’s t test and one-way analysis of variance (ANOVA) followed by the multiple comparisons Bonferroni test were used for statistical analysis. The 0.05 level of confidence was accepted as a significant difference.

RESULTS: EpiSCs-related PI3K/Akt pathway was enriched by KEGG and verified by decreased phosphorylation of Akt (32.1 ± 13.8%, P < 0.01) and mTOR (38.9 ± 11.8%, P < 0.01) in aged epidermis of rats. Furthermore, the expression of PI3K/Akt-upstream EGFR decreased with age in the epidermis of mouse (27.6 ± 5.5%, P < 0.01) and human (25.8 ± 9.3%, P < 0.01). With EGFR blocked by Erlotinib, EpiSCs showed reduced phosphorylation of Akt (30.4 ± 10.6%, P < 0.01) and mTOR (39.8 ± 12.8%, P < 0.01), impaired proliferation and migration after incubated for 24 h and 36 h (P < 0.05), and higher levels of apoptosis (11.9 ± 1.7%, P < 0.05), and rats showed slower wound healing from d7 to d14 after wounding (P < 0.01). In addition to slower wound healing rates, aged rats also showed a decrease in the efficacy of EGF, partly due to the downregulated EGFR expression. By activating PI3K/Akt pathway, Tideglusib promoted the proliferation and migration of EpiSCs with apoptosis inhibited (P < 0.01) and accelerated wound healing in aged rats from d7 to d14 after wounding (P < 0.05). Notably, the combined use of Tideglusib and EGF could further enhance wound healing in aged rats.

CONCLUSIONS: The decreased expression of EGFR in epidermis with age resulted in decreased activity of the PI3K/Akt pathway and limited EGF efficacy. Tideglusib could assist wound healing in aged rats via activating PI3K/Akt pathway, which may be considered as an ingredient for medical and cosmetics use.

PMID:35729652 | DOI:10.1186/s13287-022-02949-2

BMC Sports Sci Med Rehabil. 2022 Jun 21;14(1):116. doi: 10.1186/s13102-022-00506-1.

ABSTRACT

BACKGROUND: Sacroiliac joints (SIJs) transmitted trunk load to lower extremities through the lumbopelvis. External compression devices across the SIJs could provide stability to the SIJs. A previous study established that using a device known as Active Therapeutic Movement version 2 (ATM^®2) has been developed to improve pain and joint range of motion (ROM) in patients with LBP. However, no study has examined the physiological change in the muscle through ATM®2-based exercise thus far. This study aimed to determine the immediate effects of ATM^®2 exercise on the contraction timing, back extension endurance, muscle fatigue, and trunk ROM of lumbar and lower limb muscles in healthy subjects.

METHODS: Thirty-six healthy subjects (mean age = 23.16 ± 2.3) volunteered to participate in this study. Subjects were instructed to perform ROM test using sit and reach test, back extensor endurance test using Biering-Sorensen test, erector spinae (ES), lumbar multifidus (LM) fatigue and onset time of Gluteus maximus (GM) in prone hip extension using electromyography before and after trunk flexion and extension isometric exercises.

RESULTS: The ROM in trunk flexion showed a significant increase of 7.9% after exercise compared to that before exercise (p < 0.05). Relative GM contraction onset timing significantly decreased after exercise (p < 0.05). The result of the Sorensen test after exercise showed a trend of increase in duration time. Muscle fatigue in the LM, however, showed a significant increase (p < 0.05), whereas muscle fatigue in the ES was reduced without statistical significance.

CONCLUSIONS: The results base on this study showed that exercise-based on ATM®2 is an effective exercise protocol with an effect on the biomechanics of healthy subjects. Clinical trial registration numbers KCT0006728. Clinical trial registration date: 09/11/2021.

PMID:35729636 | DOI:10.1186/s13102-022-00506-1

Syst Rev. 2022 Jun 21;11(1):127. doi: 10.1186/s13643-022-02006-2.

ABSTRACT

BACKGROUND: Health behaviour can change outcomes in both healthy and unhealthy populations and are particularly useful in promoting compliance to treatment and maintaining fidelity to care seeking and follow-up options in chronic diseases. Interventions to change health behaviour based on psychological theory are more often successful than those without any underlying theory. The theory of planned behaviour (TPB) is one such psychological theory which had been found to predict human behaviour with respect to disease prevention and when applied to interventions can change the outcomes of diseases. Most of the research evidence of TPB-based interventions have been from developed world. Evidence is required whether TPB-based interventions can be applied and works in low-resource, low health-literacy settings of low- and middle-income countries (LMICs).

METHODS: The protocol has been developed as per PRISMA-P guidelines and incorporates PICO (population, intervention, comparison, outcomes) framework for describing the methodology. Population above 18 years of age and having any chronic disease (as defined for this systematic review) will be selected, while any health or educational intervention based on constructs of TPB will be included. Comparison will be with non-TPB-based interventions or treatment as usual without any intervention, and the primary outcome will be the behaviour change effected by the TPB-based intervention. Intervention studies will be considered, and relevant databases like MEDLINE, Embase, Cochrane Library and ProQuest will be explored. Data extraction will done in a standardised form, and risk-of-bias assessment will be done using the Cochrane Collaboration’s tools for such assessment. Narrative synthesis of the selected studies will be done to draw the conclusions, and meta-analysis will be done to calculate the effect estimates with I-squared statistics to describe the heterogeneity.

DISCUSSION: This systematic review will provide new evidence on fidelity and effectiveness of the TPB-based interventions among chronic disease patients from low health literacy, resource-poor background. It will inform of how to plan and use such interventions to change health behaviour in chronic disease patients, particularly in LMIC settings.

SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018104890 .

PMID:35729634 | DOI:10.1186/s13643-022-02006-2