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

3-D numerical simulation and analysis of complex fiber geometry RaFC materials with high volume fraction and high aspect ratio based on ABAQUS PYTHON

Organic and inorganic fiber reinforced composites with innumerable fiber orientation distributions and fiber geometries are abundantly available in several natural and synthetic structures. Inorganic glass fiber composites have been introduced to numerous applications due to their economical fabrication and tailored structural properties. Numerical characterization of such composite material systems is necessitated due to their intrinsic statistical nature, which renders extensive experimentation prohibitively time consuming and costly. To predict various mechanical behavior and characterizations of Uni-Directional Fiber Composites (UDFC) and Random Fiber Composites (RaFC), we numerically developed Representative Volume Elements (RVE) with high accuracy and efficiency and with complex fiber geometric representations encountered in uni-directional and random fiber networks. In this thesis, the numerical simulations of unidirectional RaFC fiber strand RVE models (VF>70%) are first presented by programming in ABAQUS PYTHON. Secondly, when the cross sectional aspect ratios (AR) of the second phase fiber inclusions are not necessarily one, various types of RVE models with different cross sectional shape fibers are simulated and discussed. A modified random sequential absorption algorithm is applied to enhance the volume fraction number (VF) of the RVE, which the mechanical properties represents the composite material. Thirdly, based on a Spatial Segment Shortest Distance (SSSD) algorithm, a 3-Dimentional RaFC material RVE model is simulated in ABAQUS PYTHON with randomly oriented and distributed straight fibers of high fiber aspect ratio (AR=100:1) and volume fraction (VF=31.8%). Fourthly, the piecewise multi-segments fiber geometry is obtained in MATLAB environment by a modified SSSD algorithm. Finally, numerical methods including the polynomial curve fitting and piecewise quadratic and cubic B-spline interpolation are applied to optimize the RaFC fiber geometries. Based on the multi-segments fiber geometries and aforementioned techniques, smooth curved fiber geometries depicted by cubic B-spline polynomial interpolation are obtained and different types of RaFC RVEs with high fiber filament aspect ratio (AR>3000:1) and high RVE volume fraction (VF>40.29%) are simulated by ABAQUS scripting language PYTHON programming.M.S.Includes bibliographical referencesby BoCheng Ji

Theoretical and Experimental Studies on Vibration Resistance of Composite Plates with Damping Coating

Abstract: This study performs both theoretical and experimental studies on the vibration resistance of composite plates with damping coating subjected to impulse excitation load. A dynamic model is first proposed and the key differential equations are derived to solve the natural frequencies, time-domain vibration response, and dynamic stiffness at any vibration response point regarding the excitation point of such a coated structure. Then, a dynamic experiment system of two plate specimens with and without DC knocked by a hammer excitation is set up. The measured data indicates that the proposed dynamic model is trustworthy for predicting natural frequencies and dynamic stiffness results. Furthermore, based on the calculated dynamic stiffness data associated with the first four modes, the anti-vibration contribution of DC is quantitatively evaluated. It can be found that the coating can indeed improve the vibration resistance of the structure by up to 74.7%. In addition, the vibration suppression effect of DC is found to be closely related to the mode order of such a structure as well as the selected boundary condition

Spatial and Momentum Mapping Modes for Velocity Map Imaging Spectrometer

The velocity map imaging (VMI) technique is used to acquire the momentum distribution of charged particles. Here, we introduce two additional operation modes for our recently built velocity map imaging (VMI) spectrometer: the spatial mapping mode that magnifies the image of zero energy ions with different scales and the high-resolution momentum mapping mode that acquires the electron momentum distribution at the kinetic energy of about 100 eV. In simulations, the ion image is magnified with a factor of up to 7.6, and a relative resolution of 0.15% at 150 eV electron kinetic energy is predicted. Switching between these two modes helps reduce the alignment error to below 0.2 mm. In the test using the above-threshold ionization (ATI) of argon (Ar), the Ar+ ion image is magnified by a factor of up to 6.7, and a relative resolution of 1.3% at 44.6 eV electron kinetic energy is achieved