Modeling the dynamics of photophysical and (photo)chemical reactions in extended molecular systems is a new frontier for quantum chemistry. Many dynamical phenomena, such as intersystem crossing, non-radiative relaxation, and charge and energy transfer, require a non-adiabatic description which incorporate transitions between electronic states. Additionally, these dynamics are often highly sensitive to quantum coherences and interference effects. Several methods exist to simulate non-adiabatic dynamics; however, they are typically either too expensive to be applied to large molecular systems (10's-100's of atoms), or they are based on ad hoc schemes which may include severe approximations due to inconsistencies in classical and quantum mechanics. We present, in detail, an algorithm based on Monte Carlo sampling of the semiclassical time-dependent wavefunction that involves running simple surface hopping dynamics, followed by a post-processing step which adds little cost. The method requires only a few quantities from quantum chemistry calculations, can systematically be improved, and provides excellent agreement with exact quantum mechanical results. Here we show excellent agreement with exact solutions for scattering results of standard test problems. Additionally, we find that convergence of the wavefunction is controlled by complex valued phase factors, the size of the non-adiabatic coupling region, and the choice of sampling function. These results help in determining the range of applicability of the method, and provide a starting point for further improvement.
To evaluate the use of endoscopy-assisted vitrectomy in patients with sight-threatening Bacillus cereus endophthalmitis.A retrospective analysis was conducted in 15 eyes with Bacillus cereus endophthalmitis. Patients were divided into 2 groups: endoscopy-assisted vitrectomy (5 eyes) and conventional vitrectomy (10 eyes). The following clinical data were recorded and analyzed: sex, age, latent period, symptom duration, follow-up time, visual acuity pre- and postsurgery, recurrence of endophthalmitis, incidence of phithisis bulbi, and incidence of enucleation.In the conventional vitrectomy group, postoperative visual acuity ranged from no light perception in 5 patients (50%), light perception in 3 patients (30%), 20/1000 in 1 patient (10%), and 20/50 in 1 patient (10%). In the endoscopy-assisted vitrectomy group, postoperative visual acuity ranged from no light perception in 2 patients (40%), light perception in 1 patient (20%), and hand movements in 2 patients (40%). There was no statistically significant difference between the 2 groups in terms of the final postoperative visual acuity (F = 0.006, P = .937). There is no difference between the 2 groups in terms of the incidence of enucleation. The median symptom duration was 4 hours (range: 2–6 hours) in the conventional group and 9 hours (range: 7–11 hours) in the endoscopy-assisted vitrectomy group. The difference in the symptom duration between the 2 groups was statistically significant (P = .002).There is no statistical significant difference between the 2 groups in terms of visual acuity and incidence of enucleation. Therefore, endoscopy-assisted vitrectomy can be considered as an alternative treatment for treatment of B cereus endophthalmitis particularly for cases when symptom duration was more than 6 hours.
Emergency evacuation is to transfer people from dangerous places to safe areas, so as to reduce or even avoid the potential harm to people. It is inherently a comprehensive system composed of evacuation managers, evacuees, road networks, shelters, etc. Security is one of the important indicators of such system. Moreover, in order to ensure the normal and efficient operation of evacuation system, each component should cooperate well with each other, thus making stability another important index of the evacuation system. In order to optimize evacuation safety, some residential areas may be arranged to stay much longer which is hard to be accepted, namely, the stability of evacuation system is low. In this paper, a system-based evacuation CSO model at residential level is proposed which compromises the security and stability of evacuation systems. The CSO model is a bi-level network optimization model, the upper level aims at minimizing the total risk of evacuation subject to the residential tolerance level and the lower level conveys a cell transmission-based dynamic traffic assignment problem. Using our model, we also study the impact of the number of shelters, the organizational form of road intersections, the uncertainty of evacuation demand and risk distribution on evacuation system. INDEX TERMS Evacuation management, system theory, constrained system optimal, dynamic traffic assignment, cell transmission model.
Background: Congenital heart disease (CHD) is the most common congenital defect in human beings.The purpose of this article is to investigate impact of an integrated management mode of 'prenatal diagnosispostnatal treatment' on birth, surgery, prognosis and complications associated with critical CHD (CCHD) in newborns.Methods: A retrospective analysis of the medical records of newborns diagnosed with CCHD were divided into two groups: prenatal diagnosis and postnatal diagnosis. The demographics, clinical characteristics, surgical status, prognosis and complications of the two groups were compared and the differences identified.Results: Among the 290 newborns with CCHD, 97 (33.4%) were prenatally diagnosed and 193 (66.6%) were postnatally diagnosed. Newborns in the prenatal diagnostic group were hospitalized immediately after birth, whereas the median age of admission was 6.00 (3.00-12.00) days in postnatal diagnostic group, P=0.000. In terms of postnatal symptoms and signs, the incidence of anhelation, cyanosis and cardiac murmur was higher in the postnatal diagnostic group. The rates of preoperative intubation, postoperative open chest exploration and treatment abandonment were higher in the postnatal diagnostic group. The postnatal diagnostic group was more prone to postoperative complications, such as pneumonia and hypoxicischemic brain damage. The preoperative mortality [0 (0.0%) vs. 12 (6.2%), P=0.028] in the prenatal diagnostic group was lower than that in the postnatal diagnostic group. And the one-year survival rate of the prenatal diagnostic group was higher (log-rank test P=0.034). Conclusions:The integrated management mode of prenatal diagnosis-postnatal treatment can improve postnatal symptoms, reduces complications, reduces preoperative mortality and increases one-year survival rates in newborns with CCHD.
Esophageal cancer has a high mortality rate and a poor prognosis, with more than one-third of patients receiving a diagnosis of locally advanced cancer. Esophageal squamous cell carcinoma (ESCC) is the dominant histological subtype of esophageal cancer in Asia and Eastern Europe. Although neoadjuvant or definitive chemoradiotherapy (CRT) has been the standard treatment for locally advanced ESCC, patient outcomes remain unsatisfactory, with recurrence rates as high as 30–50%. The combination of immune checkpoint inhibitors (ICIs) and CRT has emerged as a novel strategy to treat esophageal cancer, and it may have a synergistic action and provide greater efficacy. In the phase III CheckMate-577 trial, one year of adjuvant nivolumab after neoadjuvant CRT improved disease-free survival in patients with residual disease on pathology. Moreover, several phase I and II studies have shown that ICIs combined with concurrent CRT may increase the rate of pathologic complete response for resectable ESCC, but they lack long-term follow-up results. In unresectable cases, the combination of camrelizumab and definitive CRT showed promising results against ESCC in a phase Ib trial. Phase III randomized trials are currently ongoing to investigate the survival benefits of ICIs combined with neoadjuvant or definitive CRT, and they will clarify the role of immunotherapy in locally advanced ESCC. Additionally, valid biomarkers to predict tumor response and survival outcomes need to be further explored.
This paper analyses the present situation and the trend of development of the assistant teaching system at home and abroad, and designs an auxiliary teaching platform suit for modern colleges and universities combined with stratified teaching mode. The teaching platform can afford students independent learning space and time, satisfying the personality choice of the students. The auxiliary teaching platform in Colleges and Universities based on Web has finally established a teaching service system model satisfying kinds of learning needs of teachers and students, which can make up the insufficiency of after lesson interactions of existing teaching mode, promote the communication between teachers and students and advance students' independent learning ability and enhance the quality of teaching. This platform has been designed by using the B/S mode, developed by using many techniques such as ASP. NET, JavaScript, Ajax, jQuery, Web Service, and the database uses the database of SQL Server2008 R2. The system test results show that the whole system has easy operating, friendly interface and easy maintenance, and the database has stable operation, fast performance and high data security.
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