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This paper studies the numerical algorithm of stochastic control problems in investment optimization. Investors choose the optimal investment to maximize the expected return under uncertainty. The optimality condition, the Hamilton–Jacobi–Bellman (HJB) equation, satisfied by the value function and obtained by the dynamic programming method, is a partial differential equation coupled with optimization. One of the major computational difficulties is the irregular boundary conditions presented in the HJB equation. In this paper, two mesh-free algorithms are proposed to solve two different cases of HJB equations with regular and irregular boundary conditions. The model of optimal investment under uncertainty developed by Abel is used to study the efficacy of the proposed algorithms. Extensive numerical studies are conducted to test the impact of the key parameters on the numerical efficacy. By comparing the numerical solution with the exact solution, the proposed numerical algorithms are validated. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have received considerable attention due to their high theoretical specific capacity (1675 mAh g–1) and environmental friendliness. Whereas, the development of Li–S batteries has been limited by the shuttle effect and volume expansion. Binders play a key role to alleviate the above issues as an essential part of the Li–S batteries. However, there are few studies about the application of vegetable oils for preparing Li–S batteries binders. Herein, a cross–linked reactive castor oil–based binder (CAB) initiated by UV light is reported. The robust covalent cross–linking network relieves the volume expansion and ensures the stability of the electrode while numerous polar groups such as –C O and –NH– suppress the shuttle effect by immobilizing polysulfides. Therefore, the Li–S batteries with CAB binder exhibits excellent cycling stability (an initial discharge specific capacity of 1037 mAh g–1, 510 mAh g–1 after 500 cycles), and a remarkable areal capacity of 3.8 mAh cm–2 after 70 cycles even though a high sulfur loading (5.3 mg cm–2). The reactive eco–vegetable oil–based binder confirms the feasibility of UV–curable CAB as the binder for Li–S batteries and contributes to the development of efficient vegetable oil–based, reactive binders with the improved mechanical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Bronchoalveolar lavage (BAL) with pediatric flexible fibreoptic bronchoscopy (FB) is used for diagnostic and therapeutic purposes in pediatric haematopoietic stem cell transplant (HSCT) patients with pulmonary complications. The aim of our study was to evaluate complications in pediatric HSCT patients undergoing BAL/FB and to explore the nursing emphases on complications. Design and Methods: We performed a retrospective, case‐controlled study to evaluate perioperative complications of HSCT children. BAL/FB was conducted for 42 children with HSCT who experienced pulmonary complications between January 2017 and January 2018 within a tertiary hospital. Forty patients diagnosed with general pneumonia were randomly selected during the same period and served as the control group. We analyzed the signs and symptoms of all patients and compared the operative complications between the two groups. Furthermore, we presented the methods used to manage complications. Results: The presence of cough, lung rales, and imaging findings in the HSCT patients was significantly different from that of the control group (p < 0.0001). The complication rate was 66.67% (28/42) in the HSCT group and 22.5% (9/40) in the control group, and the difference was significant (p < 0.0001). Twelve out of 42 HSCT patients experienced airway mucosal bleeding (28.57%), and six had transient fever (14.29%). The topical use of epinephrine diluted saline (1:10,000) was highly effective for controlling airway mucosal bleeding without causing fluctuations in blood pressure. Practice Implications: There were more perioperative complications in the HSCT patients than in the general pneumonia patients who underwent BAL/FB. Airway mucosal bleeding was a key focus of perioperative nursing in HSCT patients undergoing bronchoscopy as main complication. BAL with the use of epinephrine diluted saline (1:10,000) effectively decreased airway mucosal bleeding. [ABSTRACT FROM AUTHOR]