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Pulmonary embolism (PE) is a disease caused by blood clots, tumor embolism, and other emboli within the pulmonary arteries. Various scoring scales are used for PE. One such same is the PESI, but it has 12 variables, making it inconvenient for clinical application.The aim of this study was to develop a new simple nomogram model to assess 30-day survival in PE patients. The new nomogram makes it easier and faster for clinicians to assess the prognosis of patients with PE.We collected data about the patients with PE from the Medical Information Mart for Intensive Care-III (MIMIC-III) database and used the receiver operating characteristic (ROC) curve, area under the ROC curve (AUROC), calibration plot, integrated discrimination improvement (IDI), and decision curve analysis (DCA) to evaluate the predictive power of the new model, and compared these with the PESI.According to the multivariable Cox regression model results, alongside the actual clinical conditions, we included the following seven variables: race, bicarbonate, age, tumor, systolic blood pressure (SBP), body temperature, and oxygen saturation (Spo2). The AUROC of the new model was greater than 0.70. Its IDI exceeded 0, but with P-value0.05.The predictive performance of the new model was not worse than the PESI, but the new model only has seven variables, and is therefore more convenient for clinicians to use.

Background Numerous studies have investigated the mean arterial pressure in patients with sepsis, and many meaningful results have been obtained. However, few studies have measured the systolic blood pressure (SBP) multiple times and established trajectory models for patients with sepsis with different SBP trajectories. Methods Data from patients with sepsis were extracted from the Medical Information Mart for Intensive Care-III database for inclusion in a retrospective cohort study. Ten SBP values within 10 h after hospitalization were extracted, and the interval between each SBP value was 1 h. The SBP measured ten times after admission was analyzed using latent growth mixture modeling to construct a trajectory model. The outcome was in-hospital mortality. The survival probability of different trajectory groups was investigated using Kaplan-Meier (K-M) analysis, and the relationship between different SBP trajectories and in-hospital mortality risk was investigated using Cox proportional-hazards regression model. Results This study included 3034 patients with sepsis. The median survival time was 67 years (interquartile range: 56–77 years). Seven different SBP trajectories were identified based on model-fit criteria. The in-hospital mortality rates of the patients in trajectory classes 1–7 were 25.5%, 40.5%, 11.8%, 18.3%, 23.5%, 13.8%, and 10.5%, respectively. The K-M analysis indicated that patients in class 2 had the lowest probability of survival. Univariate and multivariate Cox regression analysis indicated that, with class 1 as a reference, patients in class 2 had the highest in-hospital mortality risk (P Conclusion Maintaining a systolic blood pressure of approximately 140 mmHg in patients with sepsis within 10 h of admission was associated with a lower risk of in-hospital mortality. Analyzing data from multiple measurements and identifying different categories of patient populations with sepsis will help identify the risks among these categories.

Background: Heart failure (HF) is the terminal stage of various heart diseases. Conventional treatments have poor efficacy, and diuretic resistance can present. Previous studies have found that the use of glucocorticoids can enhance the diuretic effect of patients with heart failure and reduce heart failure symptoms. However, the relationship between glucocorticoid use and mortality in patients with heart failure in intensive care units is unclear.Objectives: The aim of this study was to determine the association between glucocorticoid use and all-cause mortality in critically ill patients with heart failure. Methods: The information on patients with heart failure in this study was extracted from the MIMIC-III (Medical Information Mart for Intensive Care-III) database. Patients in the glucocorticoid and non-glucocorticoid groups were matched using propensity scores. The Kaplan-Meier method was used to explore the difference in survival probability between the two groups. A Cox proportional-hazards regression model was used to analyze the hazard ratios (HRs) for the two patient groups. Subgroup analyses were performed with prespecified stratification variables to demonstrate the robustness of the results.Results: The study included 9,482 patients: 2,099 in the glucocorticoid group and 7,383 in the non-glucocorticoid group. There were 2,055 patients in each group after propensity-score matching. The results indicated that the non-glucocorticoid group was not significantly associated with reduced mortality in patients with heart failure during the 14-day follow-up period [HRs = .901, 95% confidence interval (CI) = .767–1.059]. During the follow-up periods of 15–30 and 15–90 days, the mortality risk was significantly lower in the non-glucocorticoid group than in the glucocorticoid group (HRs = .497 and 95% CI = .370–.668, and HRs = .400 and 95% CI = .310–.517, respectively). Subgroup analyses indicated no interaction among each stratification variable and glucocorticoid use.Conclusion: Glucocorticoid use was associated with an increased mortality risk in critically ill patients with heart failure.

Quantum‐mechanical calculations of the conductance for model devices, consisting of double‐quantum‐point constrictions (QPCs) connected in series by a cavity, are carried out with use of the coupled‐mode transfer method and wave‐function matching technique. The effect of the geometry‐induced scattering on the electron transport is in detail studied by varying the shape of the cavity and geometric scale of the devices. The characteristics of the conductance of the device are essentially determined by the quantum interference of the electron waves with different phases arising from multiple scattering and reflections of electrons in the cavity. When electrons are initially injected into the lowest transverse mode in the structure, as the energy of incident electrons increases the longitudinal quantum momentum of electrons becomes large and therefore electrons are substantially collimated along the propagating direction. However, when the energy of the electrons increases continuously the second conducting channel begins to open and the corresponding transverse quantum momentum of incident electrons is larger than that of the ground mode. This leads to the permitted divergent (deflection) angle for the electrons in the cavity against the propagating axis enlarges, thus, the reflection times of electrons by the cavity walls increase. The destructive interference of the multiple reflection waves leads to a conductance value less than the ideal quantization value, exhibiting ohmic‐like‐type transport with additivity of the series resistances. When the shape of the cavity takes more opening, the geometry‐induced scattering is largely suppressed and the conductance in the series dual QPC structures is finally determined by that of the QPC with the lowest conductance.

Quantum-mechanical calculations of the conductance for model devices, consisting of dual semi-infinite quantum wires connected in series by a cavity, are carried out with use of the coupled-mode transfer method and mode matching technique. The effects of the mode-mode coupling and geometry-induced scattering on the quantum conductance are in detail studied by varying the geometric structure of the cavity. There are no traces of quantization conductance. The pattern of the conductance displays many peaks and dips. The threshold energy of the first onset of the conductance is lower than the normal value for opening the propagation channel of the lowest subband in the quantum wire. The overall character of the conductance exhibits heavy fluctuations around the classical conductance for the relevant point contact. The fluctuation amplitude is of order of 2e2/h, similar to universal conductance fluctuations. The oscillatory structure becomes rich and dense as the scale of the cavity increases. There is a global trend for the conductance to rise as the cavity is compressed. The structures of resonant peaks and antiresonance dips in the conductance are originated from the mode coupling among the subbands in the cavity and quantum wires. The heavy conductance fluctuation may be caused by the quantum interference of the electron waves due to the multiple scattering (reflections) of electrons by the cavity boundaries.