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In this paper, two novel methods for predicting the frequencies for antiresonance and local extrema in the frequency response are presented. The interval searching method is based on the new criterion that takes the double antiresonance phenomenon into consideration. A novel eigenvalue formulation method for which the eigenvalues are those frequencies is also developed. Both methods can be applied to large structure because they only need one eigenvalue analysis. Two numerical examples are presented to demonstrate the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

InGaN/GaN multiple quantum well-based light-emitting diode (LED) nanopillar arrays were fabricated using Ni self-assembled nanodots as etching mask. The Ni nanodots were fabricated with a density of 6×108-1.5×109 cm-2 and a dimension of 100-250 nm with varying Ni thickness and annealing duration time. Then LED nanopillar arrays with diameter of approximately 250 nm and height of 700 nm were fabricated by inductively coupled plasma etching. In comparison to the as-grown LED sample an enhancement by a factor of four of photoluminescence (PL) intensity is achieved for the nanopillars and a blueshift as well as a decrease in full width at half maximum of the PL peak are also observed. The method of additional chemical etching was used to remove the etching-induced damage. Then nano-LED devices were further completed using a planarization approach to deposit p-type electrode on the tips of nanopillars. The current-voltage curves of both nanopillars and planar LED devices are measured for comparison. [ABSTRACT FROM AUTHOR]

This paper is to present an important issue of fatigue failure in the design of multi-fasteners jointed structure. To avoid failure in the connection area, Sines criterion is utilized. Fatigue constraints are handled in the context of stress based topology optimization. To eliminate the high stresses caused by the finite element modeling, the control volume is defined to evaluate the stress states around the fasteners. The standard topology optimization is extended to minimize the structural compliance with fatigue failure constraints. To address singularity problems related to stress constraints, q-p relaxation is used. P-norm is used as the constraints aggregation scheme. Basing on the above, the design sensitivity of fatigue constraints is derived and calculated. The proposed method is verified by a numerical example of an assembled I-beam. The comparisons of the numerical results have shown the effect of the fatigue constraint. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the diagnostic value of urinary protein and creatinine in combination with renal Doppler ultrasound examination in early renal damage of patients with hypertension. Methods: One hundred twenty two hypertensive patients who were treated in our hospital from December 2013 to June 2014 were selected for this study, including 33, 41 and 48 cases of Stage I, Stage II and Stage III hypertension respectively. Meanwhile, 30 healthy subjects were selected as the control group. They received urinary protein, creatinine and renal Doppler ultrasound examination. Results: The urinary protein levels of Stage I, II and Stage III hypertensive patients were significantly different from that of the control group (p<0.05). Urinary creatinine levels were similar (p>0.05) in stage I and II but different from control (p<0.05) in stage III. Doppler ultrasound examination showed that Stage I hypertensive patients had similar renal longest diameter (RLD), renal parenchymal thickness (RPT) and ratio of RPT/renal sinus thickness to those of the control group (p>0.05), and RLDs of Stage II hypertensive patients and the control group were not significantly different (p>0.05). Conclusion: Urinary protein and creatinine levels in combination with renal Doppler ultrasound examination could diagnose early renal damage in patients with hypertension. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the effects of connexin 37 (Cx37) interference on atherosclerotic plaques. Lentiviruses expressing small interfering RNA (siRNA) of Cx37 were constructed, and were shown to significantly knockdown the mRNA and protein expression of Cx37 in vitro. Sixty pigs on a high-fat diet were randomly divided into three treatment groups of saline, mock or Cx37 siRNA, to induce plaque formation. The Cx37 lentiviral suspension was transfected into the abdominal aortic plaques of pigs. Plaque characteristics were detected by intravascular ultrasound and the expression of Cx37 mRNA was detected by semi-quantitative polymerase chain reaction. The expression of Cx37 protein was analyzed by western blot analysis. Two months after lentivirus transfection, Cx37 mRNA levels were decreased by 38% in the Cx37 siRNA group, by 60% in the mock-siRNA group and by 63% in the saline group (P<0.05). The mock group showed no significant changes in Cx37 expression as compared with the saline group. Cx37 protein expression was lower in the Cx37 siRNA-treated group as compared with the other groups (0.21±0.07 vs. 0.65±0.06 vs. 0.54±0.07). The percentage of plaque necrosis at 10 months (two months following RNAi) was decreased in the Cx37 siRNA group as compared with that at eight months, prior to RNAi (5.26±2.11 vs. 7.83±1.03%, P<0.05). In the mock-siRNA and saline groups, no differences (P=0.074, 0.061, respectively) were observed. In the Cx37 siRNA group, plaque volumes following 10 months decreased relative to those following eight months, prior to RNAi (21.03±6.24 vs. 31.23±10.23, P<0.01). By contrast, in the mock siRNA and saline groups, plaque volumes after 10 months were increased relative to those following eight months (38.54±13.56 vs. 32.12±11.21 mm3, 37.36±14.21 vs. 30.21±12.02 mm3, P=0.031, P=0.027). Atherosclerotic plaque formation was effectively decreased through the downregulation of Cx37 mRNA using Cx37 siRNA. [ABSTRACT FROM AUTHOR]

Bronchiolitis obliterans syndrome (BOS) is a major impediment to lung transplant survival and is generally resistant to medical therapy. Extracorporeal photophoresis (ECP) is an immunomodulatory therapy that shows promise in stabilizing BOS patients, but its mechanisms of action are unclear. In a mouse lung transplant model, we show that ECP blunts alloimmune responses and inhibits BOS through lowering airway TGF-β bioavailability without altering its expression. Surprisingly, ECP-treated leukocytes were primarily engulfed by alveolar macrophages (AMs), which were reprogrammed to become less responsive to TGF-β and reduce TGF-β bioavailability through secretion of the TGF-β antagonist decorin. In untreated recipients, high airway TGF-β activity stimulated AMs to express CCL2, leading to CCR2+ monocyte-driven BOS development. Moreover, we found TGF-β receptor 2-dependent differentiation of CCR2+ monocytes was required for the generation of monocyte-derived AMs, which in turn promoted BOS by expanding tissue-resident memory CD8+ T cells that inflicted airway injury through Blimp-1-mediated granzyme B expression. Thus, through studying the effects of ECP, we have identified an AM functional plasticity that controls a TGF-β-dependent network that couples CCR2+ monocyte recruitment and differentiation to alloimmunity and BOS. [ABSTRACT FROM AUTHOR]

Abstract  The purpose of this paper was to study the layout design of the components and their supporting structures in a finite packing space. A coupled shape and topology optimization (CSTO) technique is proposed. On one hand, by defining the location and orientation of each component as geometric design variables, shape optimization is carried out to find the optimal layout of these components and a finite-circle method (FCM) is used to avoid the overlap between the components. On the other hand, the material configuration of the supporting structures that interconnect components is optimized simultaneously based on topology optimization method. As the FE mesh discretizing the packing space, i.e., design domain, has to be updated itertively to accommodate the layout variation of involved components, topology design variables, i.e., density variables assigned to density points that are distributed regularly in the entire design domain will be introduced in this paper instead of using traditional pseudo-density variables associated with finite elements as in standard topology optimization procedures. These points will thus dominate the pseudo-densities of the surrounding elements. Besides, in the CSTO, the technique of embedded mesh is used to save the computing time of the remeshing procedure, and design sensitivities are calculated w.r.t both geometric variables and density variables. In this paper, several design problems maximizing structural stiffness are considered subject to the material volume constraint. Reasonable designs of components layout and supporting structures are obtained numerically. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to develop a comprehensive dynamic modeling and analysis method based on the absolute node coordinate method to predict the impact of the member flexibility on the dynamic performance of scissor deployable structure under the framework of flexible multi-body dynamics. In the process, three locking problems in the classical plane shear beam element are reviewed and discussed. Then a novel non-locking planar beam element is proposed to solve the element locking problem, and the dynamic model of the scissor deployable structure is established. Next, the cantilever beam, simply supported beam and flexible simple pendulum are respectively used to verify the correctness of the proposed non-locking beam element from the static and dynamic perspectives. Finally, the simulation and experiment results show that the proposed new non-locking element and normal matrix modeling method can effectively evaluate the dynamic performance of deployable structure and improve the computational efficiency. This study not only provides theoretical guidance for the dynamic behavior analysis and prediction of scissor deployable structure, but also offers reference for the layout and design of same type mechanisms. [ABSTRACT FROM AUTHOR]

The stability of tailsitters is severely impacted by ground friction/reaction forces when the landing gear contacts the ground. This paper analyzes the stability of tailsitters during taking off from and landing on the ground. A distributed propulsion tailsitter with four electrically driven propellers is studied and modeled. The pitch loop of this tailsitter can be stabilized by both aerodynamic effectors immersed in the propeller slipstream and differential thrust of the propellers installed on upper and lower wing sides. The stability criteria and stability margin of tailsitters in the landing-gear/contact-ground flight stage are defined. The open-loop stability of tailsitters on high-friction and low-friction grounds is analyzed. The closed-loop stability of tailsitters with thrust-vectoring control and trailing-edge elevators control are discussed separately. On high-friction ground or uneven terrain, the tailsitter pivots about the ground contact point instead of the center of gravity. It is shown that the ground friction/reaction forces induced by the trailing-edge elevators generate a reversed pitching moment, which makes the pitch loop of the tailsitter unstable. A Proportional-Derivative controller with thrust vectoring as an effector is given and proved to guarantee the pitch loop stability. The influences of the thrust increase rate are also discussed. The experimental results of a tailsitter unmanned air vehicle verify the conclusions of this paper. [ABSTRACT FROM AUTHOR]

Developing efficient native promoters is important for improving recombinant protein expression by fungal genetic engineering. The promoter region of glyceraldehyde-3-phosphate dehydrogenase gene in Pleurotus ostreatus (Pogpd) was isolated and optimized by upstream truncation. The activities of these promoters with different lengths were further confirmed by fluorescence, quantitative real-time PCR and Western blot analysis. A truncated Pogpd-P2 fragment (795 bp) drove enhanced green fluorescence protein (egfp) gene expression in P. ostreatus much more efficiently than full-length Pogpd-P1. Further truncating Pogpd-P2 to 603, 403 and 231 bp reduced the eGFP expression significantly. However, the 403-bp fragment between -356 bp and the start codon was the minimal but sufficient promoter element for eGFP expression. Compact native promoters for genetic engineering of P. ostreatus were successfully developed and validated in this study. This will broaden the preexisting repertoire of fungal promoters for biotechnology application. [ABSTRACT FROM AUTHOR]

In this paper, we develop an efficient and flexible design method that integrates the B-spline finite cell method (B-spline FCM) and the level set function (LSF) for stress constrained shape and topology optimization. Any structure of complex geometry is embedded within an extended, regular and fixed Eulerian mesh no matter how the structure is optimized. High-order B-spline shape functions are further implemented to ensure precisions of stress analysis and sensitivity analysis. Meanwhile, level set functions, i.e., implicit functions are used to enable topological changes of the considered structure through smooth boundary variations. Involved parameters rather than the conventional discrete form of LSF are directly taken as design variables to facilitate the numerical computing process. To be specific, the LSF is constructed by means of R-functions that incorporate cubic splines as implicit functions to offer flexibilities for shape optimization within the framework of fixed mesh, while the compactly supported radial basis functions (CS-RBFs) are employed as implicit functions for stress constrained topology optimization. It is shown the proposed FCM/LSF method is a convenient approach that makes it possible to calculate stress and stress sensitivities with high precision. Representative examples of shape and topology optimization with and without stress constraints are solved with success demonstrating the advantages of the FCM/LSF method. [ABSTRACT FROM AUTHOR]

Objectives Aortic arch replacement is associated with increased mortality and morbidity especially in acute type-A aortic dissection. Although hypothermic circulatory arrest with selective antegrade cerebral perfusion has been widely used because of its excellent cerebral protection, its optimal perfusion characteristics are unknown. The present study investigates clinical results obtained after perfusion method modification and temperature management during cardiopulmonary bypass (CPB). Methods Between July 2010 and August 2012, 16 consecutive adult patients (mean age 50.0 yr ± 14.1 yr, range 25 yr to 73 yr, 12 males, 4 females) who presented with acute Stanford type-A aortic dissection underwent aortic arch replacement (total arch, n = 11; hemiarch, n = 5) under mild hypothermia (31.1°C ± 1.5°C) with right axillary and femoral artery perfusion. Results The mean CPB time was 201 min ± 53 min, and the mean myocardial ischemic time was 140 min ± 42 min. The mean selective cerebral perfusion time was 80 min ± 16 min, and the mean lower-body circulatory arrest time was 20 min ± 13 min. No patient death occurred within 30 post-operative days. The following details were observed: new post-operative permanent neurologic deficit in 1 patient (6.3%), temporary neurologic deficit in 2 patients (12.5%), acute renal dysfunction (creatinine level > 230 umol/L) in 3 patients (18.8%) and mechanical ventilation > 72 h in 5 patients (31.2%). Conclusions Aortic arch replacement for acute type-A aortic dissection under mild hypothermia with right axillary and femoral artery perfusion could be safely performed in the patient cohort. [ABSTRACT FROM AUTHOR]

The mechanisms that link bacterial infection to solid organ rejection remain unclear. In this study, we show that following the establishment of lung allograft ac-ceptance in mice, Pseudomonas aeruginosa airway in-fection induces a G-CSF--dependent neutrophilia that stimulates acute rejection. Graft-infiltrating neutro-phils sharply upregulate the B7 molecules CD80 and CD86, but they do not express CD40 or MHC class II in response to P. aeruginosa infection. Neutrophil B7 promotes naive CD4+ T cell activation and intragraft IL-2+, IFN-'V+) and IL-17+ T lymphocyte accumula-tion. Intravital two-photon microscopy reveals direct interactions between neutrophils and CD4+ T cells within pulmonary allografts. Importantly, lung rejec-tion in P. aeruginosa-infectcd recipients is triggered by CD80/86 on neutrophils and can be prevented by B7 blockade without affecting clearance of this pathogen. These data show that neutrophils enhance T cell acti-vation through B7 trans-costimulation and suggest that inhibiting neutrophil-mediated alloimmunity can be accomplished without compromising bacterial immune surveillance. [ABSTRACT FROM AUTHOR]

Abstract: Integrated layout optimization of multi-component structures under static loads and random excitations is studied in this paper. Dynamic responses are obtained by using the mode superposition method, and the prestress effect introduced by the static loads is taken into account in the analyses of dynamic responses. Locations of embedded components and pseudo-densities related to supporting structure are chosen as design variables. Design sensitivities of the dynamic responses with respect to the pseudo-densities are analytically derived. The optimization algorithm GCMMA (Global Convergent Method of Moving Asymptotes algorithm) is used to minimize simultaneously the static strain energy and dynamic responses. Three numerical examples are presented to show the validity of the optimization procedure and its potential application in practical designs. [Copyright &y& Elsevier]

In this paper, we focus on the bandlimited graph signal sampling problem. To sample graph signals, we need to find small-sized subset of nodes with the minimal optimal reconstruction error. We formulate this problem as a subset selection problem, and propose an efficient Pareto Optimization for Graph Signal Sampling (POGSS) algorithm. Since the evaluation of the objective function is very time-consuming, a novel acceleration algorithm is proposed in this paper as well, which accelerates the evaluation of any solution. Theoretical analysis shows that POGSS finds the desired solution in quadratic time while guaranteeing nearly the best known approximation bound. Empirical studies on both Erdos-Renyi graphs and Gaussian graphs demonstrate that our method outperforms the state-of-the-art greedy algorithms. [ABSTRACT FROM AUTHOR]

We provide an introduction and state of the art overview of integrated layout design of multicomponent systems. We review several packing optimization and overlap detection strategies, some tree-based methods, such as octrees and spheretrees, and a finite circle method (FCM) proposed to favor gradient-based optimization algorithms. Integrated layout design techniques for simultaneous packing and structure topology optimization of multicomponent systems are reviewed; two typical approaches for system stiffness maximization are reviewed and compared in detail. Design of multicomponent systems under inertia forces is presented using polynomial interpolation models; constraints to the centroid position, moment of inertia, and volume fraction are included. Applications to piezoelectric multi-actuated microtools and integrated layout design of bridge systems are presented. Finally, the effectiveness of the FCM, applications to 3D problems, and local optimum phenomena are discussed. [ABSTRACT FROM AUTHOR]

Granulocytes are pivotal regulators of tissue injury. However, the transcriptional mechanisms that regulate granulopoiesis under inflammatory conditions are poorly understood. Here we show that the transcriptional coregulator B cell leukemia/lymphoma 3 (Bcl3) limits granulopoiesis under emergency (i.e., inflammatory) conditions, but not homeostatic conditions. Treatment of mouse myeloid progenitors with G-CSF--serum concentrations of which rise under inflammatory conditions--rapidly increased Bcl3 transcript accumulation in a STAT3-dependent manner. Bcl3-deficient myeloid progenitors demonstrated an enhanced capacity to proliferate and differentiate into granulocytes following G-CSF stimulation, whereas the accumulation of Bcl3 protein attenuated granulopoiesis in an NF-κB p50-dependent manner. In a clinically relevant model of transplant-mediated lung ischemia reperfusion injury, expression of Bcl3 in recipients inhibited emergency granulopoiesis and limited acute graft damage. These data demonstrate a critical role for Bcl3 in regulating emergency granulopoiesis and suggest that targeting the differentiation of myeloid progenitors may be a therapeutic strategy for preventing inflammatory lung injury. [ABSTRACT FROM AUTHOR]