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In this paper, single material beams as the basic structural members in the traditional periodic frame structure were extended to the ones of multi-material composite beam with locally resonant (LR) unit. Based on the spectral element method and the topological characteristics of structure, an assembly method of the stiffness matrix for virtual full component model is presented. This method can be applied not only to the periodic structures, but also to the aperiodic structures, because the whole stiffness matrix of the structure is assembled by its topological information. The effects of the rest design parameters on the band gap behavior of two-dimension (2D) periodic frame structure were studied when the lattice constant was fixed. The results show that the Bragg band gaps can be adjusted by changing the lengths of structural members and the length ratio of the subunit A to the structural members. The results also show that the LR band gaps can be adjusted by adding LR units with different parameters into different members. The results in this work enrich and expand the modulatory pathway of the band gaps of periodic frame structure, and provide a modified approach to the design and correction of the passive vibration suppression system.

Cytogenetic and genetic changes have prognostic significance in acute myelogenous leukemia (AML). In our study, we compared the cytogenetic changes and gene mutations (NPM1, CEBPA, DNMT3A, FLT3-ITD, FLT3-TKD, and C-KIT) with clinical outcomes in 1132 patients with AML enrolled at our center over a 10-year period. A total of 977 patients provided gene mutation data. There were subsets of patients who exhibited mutations in NPM1 (17.9%), CEBPA (16.4%), FLT3-ITD (18.5%), FLT3-TKD (3.9%), DNMT3A (8.6%), and C-KIT (8.8%). A total of 557 patients (49.2%) underwent hematopoietic stem cell transplantation (HSCT) as consolidation therapy. Multivariate analysis identified an adverse karyotype (hazard ratio [HR], 1.48; P = .001), the presence of FLT3-ITD (HR, 1.90; P.001), and receipt of nonstandard first-line induction chemotherapy (HR, 1.45; P = .003) as significant risk factors for poor overall survival (OS), and the presence of CEBPA

Transplantation-associated thrombotic microangiopathy (TA-TMA) is a life-threatening complication for patients undergoing hematopoietic stem cell transplantation (HSCT). N-acetylcysteine (NAC) has recently been considered as a potential treatment for patients with thrombotic thrombocytopenic purpura. To assess the value of NAC for the prevention of TA-TMA, we conducted a prospective study at the First Affiliated Hospital of Soochow University. This open-label, randomized placebo-controlled trial included 160 patients who were scheduled for allogeneic HSCT. Participants were assigned at random 1:1 to either oral NAC (50 mg/kg/day from 9 days before HSCT to 30 days after HSCT) or placebo treatment. The primary outcome was the incidence of TA-TMA. Overall survival (OS) and event-free survival (EFS) were assessed in the NAC and placebo control groups. The incidence of TA-TMA was 9.1% (95% confidence interval [CI], 2% to 16.2%) in the NAC group, compared with 23% (95% CI, 13.2% to 32.8%) in the control group, with a rate ratio of .34 (95% CI, .123 to .911; P = .039). The median time to the onset of TA-TMA was 60 days (interquartile range [IQR], 42 to 129 days) in the NAC group and 36 days (IQR, 30.5 to 51 days) in the control group (P = .063). The 2-year OS rate was 75.4% (95% CI, 28.65% to 73.53%) in the NAC group and 63.0% (95% CI, 50.8% to 73.5%) in the control group, with a hazard ratio (HR) of .622 (95% CI, .334-1.155; P = .132). The EFS rate was 25.8% in the NAC patients and 8.1% in controls (HR, .254; 95% CI, .094 to .692; P = .024). The median time of EFS was 60 days in the NAC group and 38 days in controls. Our findings suggest that NAC may be a potential treatment to reduce the incidence of TA-TMA.

SF3B1 gene mutations are the most frequent mutations found in myelodysplastic syndromes (MDS), and the prognostic implication of these mutations remains controversial. We conducted a meta-analysis of studies assessing the prognostic impact and clinical feature of SF3B1 mutations in MDS patients. The overall hazard ratio for overall survival (OS) was 0.90 (95% confidence interval 0.60–1.35, P = 0.61) in MDS patients with SF3B1 mutations compared to those without. Lower leukemia-free survival was associated with SF3B1 mutations. Subgroup analyses showed that Asian cohorts and Illumina HiSeq 2000 methods were significantly associated with OS. Furthermore, SF3B1 mutations were significantly correlated with a lower level of blast cells and a high level of platelet counts and bone marrow ring sideroblasts. Thus, the current meta-analysis suggests that SF3B1 mutations have no significant impact on the OS of MDS patients, and the hematologic parameters of SF3B1 mutations identify a distinct subset of MDS patients with homogeneous features.

This paper investigates the influence of surface error distribution on the electromagnetic performance of antennas. The normalized Zernike polynomials are used to describe a smooth and continuous deformation surface. Based on the geometrical optics and piecewise linear fitting method, the electrical performance of reflector described by the Zernike polynomials is derived to reveal the relationship between surface error distribution and electromagnetic performance. Then the relation database between surface figure and electric performance is built for ideal and deformed surfaces to realize rapidly calculation of far-field electric performances. The simulation analysis of the influence of Zernike polynomials on the electrical properties for the axis-symmetrical reflector with the axial mode helical antenna as feed is further conducted to verify the correctness of the proposed method. Finally, the influence rules of surface error distribution on electromagnetic performance are summarized. The simulation results show that some terms of Zernike polynomials may decrease the amplitude of main lobe of antenna pattern, and some may reduce the pointing accuracy. This work extracts a new concept for reflector's shape adjustment in manufacturing process.

Introduction Severe bleeding with platelet transfusion refractoriness (PTR) is a common complication associated with reduced survival in patients with hematologic malignancies. The present study aimed to evaluate the efficacy of recombinant factor VIIa (rFVIIa) for severe bleeding complicated by PTR. Materials and methods Sixty-four patients suffering from severe bleeding with PTR hospitalized in our center between September 2012 and December 2016 were enrolled in this study. Thirty-two patients received rFVIIa (rFVIIa group) and other conventional hemostatic treatments, while the other 32 patients received conventional hemostatic treatments other than rFVIIa (control group). Results The baseline parameters of patients before treatment were similar in both groups. The total response rates to hemostatic treatment at 24 h and 48 h were significantly higher in the rFVIIa group compared with the control group (p = 0.014, p = 0.020, respectively). Significantly more patients in the rFVIIa group achieved complete responses (CR) at 24 h (p = 0.031), 48 h (p = 0.039), and 72 h (p = 0.021) compared with the control group. The bleeding score (p = 0.029), time to control bleeding (p = 0.034), and activated partial thromboplastin time (p = 0.021) after hemostatic treatment were significantly lower in the rFVIIa group compared with the control group. Patients who achieved a CR to rFVIIa had a significant survival advantage compared with those with a partial response/no response (p = 0.020). No complications with venous or arterial thromboembolism were observed during treatment. Conclusions rFVIIa may provide effective and safe hemostasis in patients suffering from severe bleeding and PTR.

Cable-membrane structure is a kind of flexible tension structures, of which both cables and membranes are lack of bending and compressing stiffness. In order to reduce the nonlinearity and the strong coupling between its geometric shape and internal stress distribution to improve the computational efficiency and convergence, this paper developed an equivalent-force density method by identifying the equivalent axial force density and equivalent transversal force density to replace the prestress in triangular and quadrilateral membrane elements. Then the method was applied as a shape-finding tool for cable-membrane structure. Furthermore, several numerical simulations, including planar cable-membrane structure, catenoid and umbrella/tent-like cable-membrane structures, were conducted to confirm the efficiency and robustness of the proposed method.

Poor platelet graft function (PPGF) is a significant complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, no optimal treatment has been recommended. This study investigated aspects of platelet recovery after allo-HSCT, including prognostic value and the effect of recombinant human thrombopoietin (rhTPO). We retrospectively analyzed 275 patients who received allo-HSCT in our center. Of them, 135 (49.1%) patients had good platelet graft function (GPGF) and 140 (50.9%) had PPGF. The latter included 59 (21.5%) patients with primary PPGF and 81 (29.4%) with secondary PPGF. Multivariate analysis showed that male gender (P = .024), lower CD34+ cell count (P = .04), and no use of rhTPO (P

In the process of surface precision adjustment of cable net structures, the establishing variable configuration of cable net structures is the basis and precondition for implementation of surface adjustment. Due to the limitation of measurement errors and uncertainties, the measured information including node location, boundary conditions and cable tensions is uncertain. In this paper, the uncertain variables are considered as the interval values, and the interval force density method is proposed to calculate the root mean square error of uncertain cable net structures. Then, the optimization model is established to find the optimal adjustment amount of adjustable cables for the higher surface accuracy. The advance and retreat algorithm is introduced to solve the optimization model. Finally, a numerical example is presented to demonstrate the feasibility and validity of the proposed surface adjustment method.

The Schapery's nonlinear viscoelastic theory and nonlinear force-density method have been investigated to analyze the creep and recovery behaviors of space deployable mesh reflectors in this paper. Based on Schapery's nonlinear viscoelastic theory, we establish the creep and recovery constitutive model for cables whose pretensions were applied stepwise in time. This constitutive model has been further used for adjustment of cables’ elongation rigidity. In addition, the time-dependent tangent stiffness matrix is calculated by the partial differentiation of the corresponding load vector with respect to the nodal coordinate vector obtained by the nonlinear force-density method. An incremental-iterative solution based on the Newton-Raphson method is adopted for solving the time-dependent nonlinear statics equations. Finally, a hoop truss reflector antenna is presented as a numerical example to illustrate the efficiency of the proposed method for the creep and recovery behavior analysis of space deployable mesh structures.

The main purpose of the paper is to investigate the effects of structural parameters of deployable reflectors on their mean cable tensions. The proportional relations between spatial and plane cable nets are firstly explored on the basis of projection principle. By the means of obtained proportional relations, the analytical expressions between the mean spatial cable tensions and structural parameters of deployable reflectors including aperture, subdivision number and focal length are then derived. In the following, a modified plane projection method is proposed for pretension design of offset reflectors. Finally, numerical simulations are taken to verify the analytical expressions, as well as the modified plane projection method. The results show that the mean spatial cable tensions are predicted accurately by the analytical expressions, and uniform tension distribution is obtained by the modified plane projection method. With the applications of the analytical expressions and the modified plane projection method, the cable tensions can be controlled more flexible and convenient in engineering applications.

Background Graft-versus-host disease (GVHD) is a leading cause of death in patients after hematopoietic stem-cell transplantation (HSCT). Previous studies have shown different efficacy of GVHD prophylaxis therapies. Methods We reviewed 46 randomized controlled trials (including 8050 participants) systematically from Jun 20, 2004 to Aug 20, 2019. These investigations compared the following drugs or their combination at therapeutic dose range for GVHD after HSCT. The main results were based on the proportion of patients who respond to these therapies. Results Cyclosporine + methotrexate + Anti-T cell globulin (ATG), tacrolimus + methotrexate + ATG, tacrolimus + bortezomib + sirolimus and cyclosporine + marrow mesenchymal stem cells (MMSCs) were significantly more efficacious than corticosteroids alone (OR: 12.15, 6.71, 6.25, 3.73). corticosteroids alone were less efficacious than all the other GVHD prophylaxis therapies tested. Conclusion Cyclosporine + methotrexate + ATG may be the best choice when starting treatment for GVHD.

This paper performs an analysis to the systematic surface figure error influenced by three factors including errors of faceted paraboloids, fabrication imperfection and random thermal strains in orbit. Firstly, the computational formulas for root-mean-square surface deviations caused by these factors are presented respectively. The stochastic finite element method is applied to derive the computational formulas of fabrication imperfection and random thermal strains, by which the sensitivity of surface accuracy to component imperfection can be revealed. Then the Monte Carlo simulation method is introduced to obtain the surface figure by sampling test on random errors. Finally, the analytical method is applied to the research on the surface figure error of AstroMesh deployable reflector. The results show that the deviations between the root-mean-square surface errors calculated by the proposed formulas with less consuming time and those by the Monte Carlo simulation method are less than 2%, which indicates that the proposed method is efficient and receivable enough to analyze systematic surface figure error of a large deployable antenna. Moreover, further investigations on the relationship between surface RMS deviation and the antenna parameters including aperture and the number of subdivisions are presented in the end.

Phosphatase and tensin homolog located on chromosome 10 (PTEN) is one of the most frequently mutated tumor suppressors in human cancer including in glioblastoma. Here, we show that PTEN exerts unconventional oncogenic effects in glioblastoma through a novel PTEN/mutant p53/c-Myc/Bcl-XL molecular and functional axis. Using a wide array of molecular, genetic, and functional approaches, we demonstrate that PTEN enhances a transcriptional complex containing gain-of-function mutant p53, CBP, and NFY in human glioblastoma cells and tumor tissues. The mutant p53/CBP/NFY complex transcriptionally activates the oncogenes c-Myc and Bcl-XL, leading to increased cell proliferation, survival, invasion, and clonogenicity. Disruption of the mutant p53/c-Myc/Bcl-XL axis or mutant p53/CBP/NFY complex reverses the transcriptional and oncogenic effects of PTEN and unmasks its tumor-suppressive function. Consistent with these data, we find that PTEN expression is associated with worse patient survival than PTEN loss in tumors harboring mutant p53 and that a small molecule modulator of p53 exerts greater antitumor effects in PTEN-expressing cancer cells. Altogether, our study describes a new signaling pathway that mediates context-dependent oncogenic/tumor-suppressive role of PTEN. The data also indicate that the combined mutational status of PTEN and p53 influences cancer prognosis and anticancer therapies that target PTEN and p53.