Detailed simulations of particle breakage as a result of agitation

Peer reviewedPostprin

Experiments and simulations of settling cylinders over a wide range of Archimedes numbers

This work was supported by the National Natural Science Foundation of China (Nos. 22078191, 21978165, 22081340412).Peer reviewedPostprin

Development and validation of platelet-to-albumin ratio as a clinical predictor for diffuse large B-cell lymphoma

IntroductionDiffuse large B-cell lymphoma (DLBCL) is the most common subtypes of lymphoma. Clinical biomarkers are still required for DLBCL patients to identify high-risk patients. Therefore, we developed and validated the platelet-to-albumin (PTA) ratio as a predictor for DLBCL patients.MethodsA group of 749 patients was randomly divided into a training set (600 patients) and an internal validation set (149 cases). The independent cohort of 110 patients was enrolled from the other hospital as an external validation set. Penalized smoothing spline (PS) Cox regression models were used to explore the non-linear relationship between the PTA ratio and overall survival (OS) as well as progression-free survival (PFS), respectively.ResultsA U-shaped relation between the PTA ratio and PFS was identified in the training set. The PTA ratio less than 2.7 or greater than 8.6 was associated with the shorter PFS. Additionally, the PTA ratio had an additional prognostic value to the well-established predictors. What’s more, the U-shaped pattern of the PTA ratio and PFS was respectively validated in the two validation sets.DiscussionA U-shaped association between the PTA ratio and PFS was found in patients with DLBCLs. The PTA ratio can be used as a biomarker, and may suggest abnormalities of both host nutritional aspect and systemic inflammation in DLBCL

EFFECTS OF CHARACTERISTICS OF THE OBSERVED AND THE OBSERVERS ON SPATIAL KNOWLEDGE ACQUISITION

Ph.DDOCTOR OF PHILOSOPH

An Integrated Simplification Approach for 3D Buildings with Sloped and Flat Roofs

Simplification of three-dimensional (3D) buildings is critical to improve the efficiency of visualizing urban environments while ensuring realistic urban scenes. Moreover, it underpins the construction of multi-scale 3D city models (3DCMs) which could be applied to study various urban issues. In this paper, we design a generic yet effective approach for simplifying 3D buildings. Instead of relying on both semantic information and geometric information, our approach is based solely on geometric information as many 3D buildings still do not include semantic information. In addition, it provides an integrated means to treat 3D buildings with either sloped or flat roofs. The two case studies, one exploring simplification of individual 3D buildings at varying levels of complexity while the other, investigating the multi-scale simplification of a cityscape, show the effectiveness of our approach

Managerial multi-tasking, team diversity, and mutual fund performance

This book is the first to explore the issue of corporate governance in China's new corporations. With rapid development over the last two decades, China has seen compelling achievements in overseas investment. Specifically, an increasing number of Chinese companies have been “going out” to become multinational enterprises. From the practical view, corporate governance issues have been identified in the literature as one of the most important factors in determining whether these Chinese multinational enterprises succeed or not. However, existing literature provides little investigation and understanding about corporate governance of Chinese multinational enterprises. This book fills that gap and will be of value to corporate executives, scholars of China's economy, and journalists

An Assessment of Social Distancing Obedience Behavior during the COVID-19 Post-Epidemic Period in China: A Cross-Sectional Survey

Social distancing plays a critical role in reducing the disease diffusion risk during the COVID-19 pandemic and post-pandemic period. In order to explore the social distancing obedience behavior, a comprehensive survey was conducted in this study by collecting data from 1064 Chinese residents in January 2021 by means of a questionnaire. Structural equation modeling (SEM) and hierarchical linear regression (HLR) analyses were employed to investigate the research hypotheses considered, testing the three influencing factors of social distancing obedience behavior: public guidance, risk perception, and regulation punishment. The reliability and validity of the measurements are demonstrated. The outcomes from the conducted analyses show that the public guidance significantly affects risk perception of individuals, while risk perception imposes a positive impact on social distancing obedience behavior. Moreover, risk perception serves a mediating role in the relationship between the public guidance and social distancing obedience behavior. In addition, regulation punishment positively predicts social distancing obedience behavior and could even have a greater effect by enhancing risk perception. Hence, this study suggests that the relevant authorities and agencies implement strong social distancing policies during the COVID-19 post-pandemic period from the perspective of promoting the public guidance, risk perception, and regulation punishment

Sequential bonding of CO molecules to a titanium dimer: A photoelectron velocity-map imaging spectroscopic and theoretical study of Ti-2(CO)(n)(-) (n=1-9)

Binuclear titanium carbonyl cluster anions, Ti-2(CO)(n)(-) (n = 4-6), are produced via a laser vaporization supersonic cluster source and characterized by mass-selected photoelectron velocity-map imaging spectroscopy. Quantum chemical calculations are carried out for Ti-2(CO)(n)(-) (n = 1-9) to explore the trend of sequential bonding of CO molecules to a titanium dimer. It has been found that the CO molecules bind to Ti-2 in a side-on fashion and form a stable Ti-2[eta(2)(mu(2)-C,O)](3) structure at n = 3, the motif of which retains up to n = 5. Starting at n = 6, a new building block of two CO groups side-on-bonded to Ti-2 is favored, the structure of which persists up to n = 9. In the larger clusters (n = 6-9), the side-on-bonded CO molecule can be stabilized via the removal of two electrons from an anionic titanium carbonyl, which is different from the effect of charge on CO binding in rhodium carbonyls where bridge-bonded CO molecules are selectively destabilized by the removal of an electron from a neutral rhodium carbonyl. The present study provides a stepwise picture for molecular-level understanding of CO bonding on transition-metal clusters, which is directly relevant to the elementary processes of CO at metal catalysts. Published by AIP Publishing

3D Environment Mapping with a Variable Resolution NDT Method

With the continuous development of the 3D LiDAR (Light Detection And Ranging) mapping algorithm and its application in various fields, the size of the point cloud map becomes a bottleneck that limits the 3D LiDAR mapping algorithm from running for a long time. In this paper, a 3D LiDAR mapping method based on scan-to-map and variable resolution NDT (normal-distributions transform) registration is proposed. When updating the global map, variable resolution processing can reduce the size of the global map and improve the accuracy of map construction. In addition, the size of the map created by the mapping algorithm is proportional to the size of the space and does not grow infinitely over time. The mapping experiments using a rotating LiDAR in the room, corridor, and outdoor environments show that the algorithm has higher mapping accuracy and smaller map size than without considering the variable resolution strategy. The experimental results of the map construction for a long time in an appropriate test area illustrate that the map built by the algorithm does not grow infinitely with time in the fixed space. In summary, by adjusting the map resolution adaptively according to the curvature of different areas in the 3D LiDAR mapping process, the proposed variable resolution strategy can maintain the size of the global map almost proportional to the size of the space. Moreover, the mapping accuracy can be improved as well

Probing the microhydration of metal carbonyls: a photoelectron velocity-map imaging spectroscopic and theoretical study of Ni(CO)3(H2O)n.

A series of microhydrated nickel carbonyls, Ni(CO)3(H2O)n- (n = 0-4), are prepared via a laser vaporization supersonic cluster source in the gas phase and identified by mass-selected photoelectron velocity-map imaging spectroscopy and quantum chemical calculations. Vertical detachment energies for the n = 1-4 anions are measured from the photoelectron spectra to be 1.429 ± 0.103, 1.698 ± 0.090, 1.887 ± 0.080, and 2.023 ± 0.074 eV, respectively. The C-O stretching vibrational frequencies in the corresponding neutral clusters are determined to be 1968, 1950, 1945, and 1940 cm-1 for n = 1-4, respectively, which are characteristic of terminal CO. It is determined that the hydrogen atom of the first water molecule is bound to the nickel center. Addition of a second water molecule prefers solvation at the carbonyl terminal. Spectroscopy combined with theory suggests that the solvation of nickel tricarbonyl is dominated by a water-ring network. The present findings would have important implications for the fundamental understanding of the multifaceted mechanisms of the multibody interaction of water and carbon monoxide with transition metals