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In this paper, we propose and analyze a three-dimensional fractional predator–prey system with two nonidentical delays. By choosing two delays as the bifurcation parameter, we first calculate the stability switching curves in the delay plane. By judging the direction of the characteristic root across the imaginary axis in stability switching curves, we obtain that the stability of the system changes when two delays cross the stability switching curves, and then, the system appears to have bifurcating periodic solutions near the positive equilibrium, which implies that the trajectory of the system is the axial symmetry. Secondly, we obtain the conditions for the existence of Hopf bifurcation. Finally, we give one example to verify the correctness of the theoretical analysis. In particular, the geometric stability switch criteria are applied to the stability analysis of the fractional differential predator–prey system with two delays for the first time. [ABSTRACT FROM AUTHOR]

Objective: Septoplasty has been the definitive treatment for nasal septum deviation, but its postoperative procedure may affect patients' quality of life. While new procedures in general surgery, such as enhanced recovery after surgery (ERAS), can speed up postoperative rehabilitations to improve quality of life, it is rarely applied in the ear-nose-throat field. This study therefore aims to evaluate the application of ERAS in patients with nasal septum deviation as a means of improving perioperative outcomes.Materials and Methods: Fifty patients with nasal septum deviation undergoing septoplasty were randomized as ERAS or control group (25 patients in both groups). Patients were investigated for outcomes including length of stay, operating time, bleeding volume, total cost, complications, and Self-Rating Anxiety Scale (SAS) and visual analog symptom score of nasal obstruction, sleep disturbance, and head facial pain.Results: The preoperative anxiety in ERAS group (SAS 35.4±6.2) was lower than the control group (SAS 43.6±8.6). The anxiety levels in ERAS group (SAS 31.6±5.4) was also reduced compared to the control group (SAS 38.1±10.4) in the 3 days postsurgery, but showed no significant difference thereafter at 7 days postsurgery. In addition, the length of stay and total cost were significantly lower for the ERAS group as well. The visual analog symptom score of nasal obstruction, sleep disturbance, and head facial pain in ERAS group were all also found to be lower than the control group. The only outcomes with no significant differences were the operation time, blood volume, and complications between the groups.Conclusion: Our study indicated ERAS application can reduce hospital charges and postoperative pain in septoplasty, thereby improving patient quality of life and hospital expenses at the same time. [ABSTRACT FROM AUTHOR]

A class Γ of graphs is χ-bounded if there eχists a function f such that χ (G) ⩽ f (&oωega; (G)) for all graphs G ϵ Γ, ωhere χ denotes chromatic number and ω denotes clique number. Gyárfás and Sumner independently conjectured that, for any tree T, the class Forb (T), consisting of graphs that do not contain T as an induced subgraph, is χ-bounded. The first author and Penrice showed that this conjecture is true for any radius two tree. Here we use the work of several authors to show that the conjecture is true for radius three trees obtained from radius two trees by making exactly one subdivision in every edge adjacent to the root. These are the only trees with radius greater than two, other than subdivided stars, for which the conjecture is known to be true. [ABSTRACT FROM AUTHOR]

• The effects of maternal exposure to air pollutants on fetal growth were assessed. • CO exposure during pregnancy was associated with lower fetal growth. • Also, O 3 , PM 2.5 , and PM 10 exposures were associated with a small decrement in birth weight. • Term LBW were not linked to maternal exposure to air pollutants. • Maternal age and infant sex modified the impact of air pollution on birth weight. Evidence is scarce on the relation between maternal exposure to ambient air pollution during pregnancy and fetal growth in developing countries. Moreover, the current evidence is inconsistent. We aimed to investigate the association of trimester-specific exposure to air pollution with risk of being born small for gestational age (SGA) and birth weight-markers of fetal growth-among Chinese term births. This retrospective population-based cohort study consisted of 2,567,457 singleton term live-births from January 1, 2014 to December 31, 2017 across 123 Chinese districts and counties. Personal exposure to ambient air pollutants including carbon monoxide (CO), sulfur dioxide (SO 2), nitrogen dioxide (NO 2), ozone (O 3), particulate matter with aerodynamic diameter < 2.5 μm (PM 2.5), and PM 10 was assigned using the inverse distance weighting spatial interpolation algorithm. Generalized estimating equations (GEE) logistic regression models were performed to estimate the associations between trimester-specific exposure to air pollution and risk of SGA or low birth weight (LBW), and GEE linear regression to examine the associations between the exposure and term birth weight, adjusting for maternal demographics, maternal cigarette smoking status during pregnancy, mode of delivery, gravidity, gestational age, year and month of conception, neonate's sex, and meteorological factors. Stratified and sensitivity analyses were also performed. When mother exposed to ambient air pollutants over the entire pregnancy, per IQR increment (0.122 mg/m3) in ambient CO concentrations was associated with higher risk of SGA (odds ratio (OR) = 1.04, 95% confidence interval (CI): 1.02, 1.05) and reduced birth weight among term births (−5.95 g, 95% CI: −8.01, −3.89). This association was also pronounced in the second and third trimesters. Term birth weight was negatively associated with per IQR increase of O 3 (−3.52 g, 95% CI: −6.23, −0.81), PM 2.5 (−5.93 g, 95% CI: −8.36, −3.49) and PM 10 (−7.78 g, 95% CI: −10.41, −5.16) during the entire pregnancy, respectively. No significant association was detected between maternal exposure to air pollutants and term LBW. Effect estimates of heterogeneity suggested that maternal age and infant sex modified the impact of air pollution on birth weight. The findings suggest that maternal exposure to air pollution during pregnancy is adversely affecting fetal growth. Further studies are warranted to integrate these findings and take clinical or public health interventions in pregnancy. [ABSTRACT FROM AUTHOR]