bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unlocking the Single‐Domain Epitaxy of Halide Perovskites
Authors: Wang Lili , Chen Pei , Thongprong Non , Young Margaret , Kuttipillai Padmanaban S. , Jiang Chuanpeng , Zhang Pengpeng , Sun Kai , Duxbury Phillip M. , Lunt Richard R. 
Published: September 2017

AbstractThe growth of epitaxial semiconductors and oxides has long since revolutionized the electronics and optics fields, and continues to be exploited to uncover new physics stemming from quantum interactions. While the recent emergence of halide perovskites offers exciting new opportunities for a range of thin‐film electronics, the principles of epitaxy have yet to be applied to this new class of materials and the full potential of these materials is still not yet known. In this work, single‐domain inorganic halide perovskite epitaxy is demonstrated. This is enabled by reactive vapor phase deposition onto single crystal metal halide substrates with congruent ionic interactions. For the archetypical halide perovskite, cesium tin bromide, two epitaxial phases, a cubic phase and tetragonal phase, are uncovered which emerge via stoichiometry control that are both stabilized with vastly differing lattice constants and accommodated via epitaxial rotation. This epitaxial growth is exploited to demonstrate multilayer 2D quantum wells of a halide‐perovskite system. This work ultimately unlocks new routes to push halide perovskites to their full potential.
Catanionic Coacervate Droplets as a Surfactant‐Based Membrane‐Free Protocell Model
Authors: Douliez Jean‐Paul , Martin Nicolas , Gaillard Cédric , Beneyton Thomas , Baret Jean‐Christophe , Mann Stephen , Beven Laure 
Published: September 2017

AbstractWe report on the formation of surfactant‐based complex catanionic coacervate droplets in mixtures of decanoic acid and cetylpyridinium chloride or cetyltrimethylammonium bromide. We show that coacervation occurs over a broad range of composition, pH, and ionic strength. The catanionic coacervates consist of elongated micelles, sequester a wide range of solutes including water‐soluble organic dyes, polysaccharides, proteins, enzymes, and DNA, and can be structurally stabilized by sodium alginate or gelatin‐based hydrogelation. These results suggest that catanionic coacervates could be exploited as a novel surfactant‐based membrane‐free protocell model.
Characteristics of different mesh types for abdominal wall repair in an experimental model of peritonitis
Authors: Kaufmann R , Jairam A P , Mulder I M , Wu Z , Verhelst J , Vennix S , Giesen L J X , Clahsen-van Groningen M C , Jeekel J , Lange J F 
Published: September 2017

Abstract

Background
The use of synthetic mesh to repair a potentially contaminated incisional hernia may lead to higher failure rates. A biological mesh might be considered, but little is known about long-term results. Both biological and synthetic meshes were investigated in an experimental model of peritonitis to assess their characteristics in vivo.

Methods
Male Wistar rats were randomized into five groups and peritonitis was induced. A mesh was implanted after 24 h. Five meshes were investigated: Permacol™ (cross-linked collagen), Strattice™ (non-cross-linked collagen), XCM Biologic® (non-cross-linked collagen), Omyra® Mesh (condensed polytetrafluoroethylene) and Parietene™ (polypropylene). The rats were killed after either 30, 90 or 180 days. Incorporation and shrinkage of the mesh, adhesion coverage, strength of adhesions and histology were analysed.

Results
Of 135 rats randomized, 18 died from peritonitis. Some 180 days after implantation, both XCM Biologic® and Permacol™ had significantly better incorporation than Strattice™ (P = 0·003 and P = 0·009 respectively). Strattice™ had significantly fewer adhesions than XCM Biologic® (P = 0·001) and Permacol™ (P = 0·020). Thirty days after implantation, Permacol™ had significantly stronger adhesions than Strattice™ (P &lt; 0·001). Shrinkage was most prominent in XCM Biologic®, but no significant difference was found compared with the other meshes. Histological analysis revealed marked differences in foreign body response among all meshes.

Conclusion
This experimental study suggested that XCM Biologic® was superior in terms of incorporation, macroscopic mesh infection, and histological parameters such as collagen deposition and neovascularization. There must be sufficient overlap of mesh during placement, as XCM Biologic® showed a high rate of shrinkage. Surgical relevanceThe use of synthetic mesh to repair a potentially contaminated incisional hernia is not supported unequivocally, and may lead to a higher failure rate. A biological mesh might be considered as an alternative. There are few long-term studies, as these meshes are expensive and rarely used.This study evaluated the use of biological mesh in a contaminated environment, and investigated whether there is an ideal mesh. A new non-cross-linked biological mesh (XCM Biologic®) was evaluated in this experiment.The new non-cross-linked biological mesh XCM Biologic® performed best and may be useful in patients with a potentially contaminated incisional hernia.
Hemophagocytic syndrome in pregnancy: case report, diagnosis, treatment, and prognosis
Authors: Rousselin Aline , Alavi Zarrin , Le Moigne Emmanuelle , Renard Sarah , Tremouilhac Christophe , Delluc Aurélien , Merviel Philippe 
Published: September 2017

Key Clinical MessageDiagnosis of hemophagocytic syndrome remains a challenge in particular during pregnancy. Concomitant presence of clinical and biological signs, for example, fever, pancytopenia, hyperferritinemia, and hypertriglyceridemia, should alert clinicians to suspect HPS and proceed to prompt treatments.
Vaccine‐associated measles in an immunocompetent child
Authors: Sood Shawn B. , Suthar Krishna , Martin Kimberly , Mather Keith 
Published: September 2017

Key Clinical MessageWe present a rare case of vaccine‐associated measles infection in an immunocompetent, HIV‐negative patient in the United States. This case depicts the impressive rash our patient manifested and highlights the importance of reviewing public health interventions to determine epidemiological links in geographical areas with low incidence of measles.
03.27: Punching shear behaviour of an innovative connection between steel tubular column to flat concrete slab
Authors: Wang Yongchang , Yu Junlong 
Published: September 2017

ABSTRACTThis paper presents the results of an experimental investigation into the punching shear behaviour and resistance of a simple and effective method of connection between steel tubular column and concrete flat slab using welded shear studs. The shear stud used is the same type as used in conventional steel/concrete composite beams. A major difference between the shear stud behaviour in the proposed system and in composite beam is that in the proposed system, the amount of concrete available to resist punching shear is limited due to small depth of the flat concrete slab. The experimental studies have investigated the effects on punching shear behaviour and resistance of the proposed shear connection system under different design variables including concrete depth above the shear stud, concrete grade, and shear stud dimensions (length and diameter). The results indicate that it is possible to use the proposed simple connection system to provide sufficient punching shear resistance in realistic flat slab construction. Punching shear resistance is dependent on the concrete depth above shear stud. Concrete grade is also important, however, it is the concrete tensile strength that directly determines punching shear resistance. The dimensions of shear stud have relatively minor influences.
03.28: Performance of cruciform finite elements that model 2D steel joints with beams of unequal depth in frame analysis
Authors: Bayo Eduardo , Loureiro Alfonso , Lopez Manuel 
Published: September 2017

ABSTRACTThis paper deals with the performance evaluation of cruciform finite elements with 4 nodes and 12 degrees of freedom that model 2D steel joints with beams of unequal depth in frame analysis. These elements are capable of modelling joints that have double rectangular panels, with or without horizontal stiffeners in the panel zone, due to beams of different depths at both sides of the joint. In addition, these cruciform elements are suitable for simple, rigid and semi‐rigid connections and therefore can be used for the global analysis of semi‐rigid steel frames. The performance of these elements is assessed by analysing steel frames under different loading conditions, and comparing the results with complete finite element models.The characteristics of these elements (stiffness and resistance) are generated by a previously proposed displacement based modal approach. All the forces and moments coming from the adjacent beams and columns concur at the joint, therefore, the complete force field in the panel zones is known with no need for a transformation parameter β (EC3‐Part 1.8). The proposed element also avoid the use of mechanical models (composed of springs and rigid bars) for frame analyses, which add complexity, numerical overhead —consequence of the larger number of degrees of freedom— and possible round off errors (due to the rigid bars) in the solution process.In addition, since the real dimensions of the joint are included in the proposed elements, the eccentric moments are automatically taken into account. Also, the interaction between the deep and the shallow sides of the column double panels are considered. Numerical simulations and comparison with complete finite element models are carried out that show the validity and computational efficiency of these elements.
03.31: Influence of design parameters on mechanic behavior of prefabircated self‐centering beam‐column connection with a bolted web friction device
Authors: Zhang Yanxia. , Liu Anran. , Shao Dinan. , Liu Xuechun. 
Published: September 2017

ABSTRACTA new prefabricated self‐centering beam‐column connection (hereafter known as PSCC) using the bolted web friction devices has been proposed. The connection can avoid the on‐site aerial tension for high‐rise buildings. Experimental study and the numerical simulation have been carried out to investigate the mechanic performance of PSCC. In this thesis, on the basis of coincidence of experimental results and numerical simulation analysis results, the panel zone strength, the cable forces are selected as parameters to investigate initial stiffness, gap‐opening stiffness, imminent moment of gap‐opening, maximum gap‐opening moment, cable forces of the connection of the new type PSCC under various working conditions through the finite element software ABAQUS. From the FEA results, it can be verified that initial stiffness, gap opening stiffness, critical moment and cable force increases with the development of the panel zone strength, the energy dissipating coefficient not change much. The plasticity in panel zone decreases, but the minimum plastic development in flanges and webs of the short‐beam portions occur in the connection with medium panel zone strength. Additionally, increase of the cable forces are identified to have influence on developing the initial stiffness, gap opening stiffness, critical moment, while it may decrease the dissipating coefficient, and develop the plasticity in main parts of PSCC. The parametric analysis can lay foundation for the further performance based design towards PSCC.
03.32: Analytical prediction of moment‐rotation behaviour of austenitic stainless steel bolted connections
Authors: Hasan Mohammad Jobaer , Ashraf Mahmud , Uy Brian 
Published: September 2017

ABSTRACTSteel framework is one of the most commonly used structural systems in modern construction and beam‐to‐column connections play a significant role in overall performance of the structure. Semi‐rigid behaviour of steel connections was investigated both experimentally and numerically over the last few decades. Stainless steel alloys are now increasingly used in construction industry owing to their superior material properties such as corrosion resistance, higher strength, enhanced ductility, significantly lower maintenance cost and attractive appearance. In this study, the performance of stainless steel top‐seat with or without double web angle (DWA) bolted connections are analytically investigated using a proposed four parameter power model assuming plastic hinges are formed in the connected angles. The proposed analytical model can predict the moment‐rotation behaviour using four key connection parameters such as initial stiffness, strain hardening stiffness, reference plastic rotation and shape parameter. These key parameters were expressed as functions of easily obtainable geometric and material properties. This model allows to predict complete moment‐rotation curves for stainless steel connections using the knowledge of easily available properties and configurations of the connecting elements. Analytically predicted moment‐rotation curves were compared with those obtained using 3D finite element models, and showed good agreement with actual connection behaviour.
04.04: Buckling of elastic cylindrical shells under symmetric but non‐uniform bending moment distributions
Authors: Wang Jie , Sadowski Adam J. 
Published: September 2017

ABSTRACTThe behaviour of cylindrical shells and circular hollow sections under uniform bending has long received significant research attention. This is mainly due to the phenomenon of Brazier cross‐sectional ovalisation which is known to lead to an almost 50% reduction in the buckling moment relative to the classical analytical prediction. However, very little research appears to have been carried out to investigate the ovalisation behaviour under non‐uniform bending moment distributions (BMDs). This appears to be because until only relatively recently, most studies on the topic were analytical in nature which made the buckling analysis of anything but a uniform BMD difficult. With the rise of modern computing it is now possible to undertake extensive parametric studies to investigate any desired load condition.This paper employs the finite element method to explore the elastic stability of perfect simply‐supported cylinders or tubes under load cases that represent symmetric parabolic and triangular BMDs, and to compare them with the behaviour under the hitherto most‐commonly studied uniform BMD. Each non‐uniform BMD is investigated by four different three‐dimensional shell loading arrangements. While these all share the same resultant BMD, they exhibit very different buckling behaviours illustrating the ambiguity inherent in realistically modelling such systems. This is a consequence of the loss of uniqueness when projecting a 1D construct onto a 3D space.In addition to linear bifurcation analyses, nonlinear elastic buckling analyses are presented to explore the effect of ovalisation at long lengths under the proposed loading arrangements. It is found that ovalisation becomes fully developed at approximately the same dimensionless length and leads to a similar ∼50% reduction in the buckling strength of asymptotically long cylinders for almost any representation of the three considered symmetric BMDs.
04.08: Investigations on the buckling behaviour of slender high strength steel plates under multiaxial stresses
Authors: Pourostad Vahid , Zizza Antonio , Kuhlmann Ulrike 
Published: September 2017

ABSTRACTCurrent design code EN 1993‐1‐5 [1] offers, apart from the possibility of using the Finite Element Method, generally two different methods for the design of slender plates subjected to plate buckling. The first method, called “effective width method”, is based on the reduction of the cross‐section area. The second method, which may be used for the design of plated structures, is the so called “reduced stress method”. It is a classic concept that limits the allowable stresses in the plate and uses a kind of von‐Mises criterion to check the combination of different stresses. The reduction of the allowable stresses in comparison with the full strength is a function of the slenderness of the considered plate and depends on the critical buckling stress. For the “reduced stress method”, according to EN 1993‐1‐5 the determination of the plate slenderness is based on the complete stress field, resulting in a single plate slenderness without the differentiation for the individual acting forces. This gives theoretically the possibility of also considering tension stresses for a multiaxially loaded plate subjected to buckling, as there is a direct influence when determining the plate slenderness.Furthermore, recent investigations conducted by [2] on unstiffened plates under biaxial compression, showed that the current rules EN 1993‐1‐5 may give unsafe results, so that a correction is proposed by introducing a so‐called “V‐factor” in the design formula. [4] presented the influence of tension stresses on the buckling behaviour of multiaxially loaded plates and developed a “V‐factor” for the tension‐compression interaction domain to profit from the favourable effects of tension stresses.The aim of this paper, based on [4], is to show experimental as well as numerical analyses on the buckling behaviour of multiaxially loaded high strength steel plates. The numerical simulations are compared to the test results. Furthermore, the validity of the proposed V‐factor is studied. Thus, the investigations increase the insight in the buckling behaviour under multiaxial stress states allowing for an enhancement of the current design rules, focusing on the reduced stress method according to Chapter 10, EN 1993‐1‐5.
04.09: Cylindrically curved steel panels in bridge design: Buckling and post‐buckling behaviour under shear stresses
Authors: Ljubinković Filip , Martins João Pedro , da Silva Luís Simões 
Published: September 2017

ABSTRACTThe main goal of this work is to investigate the behaviour of the cylindrically curved steel panels subjected to pure in‐plane shear stresses. The most relevant works regarding the simply supported curved panels under shear stresses were firstly revised and based on these studies the numerical models were calibrated. As one of the main objectives of this study, the influnce of aspect ratio and curvature parameter on both elastic buckling and post‐buckling behavior of curved panels was analysed. Regarding the curvature parameter, it was concluded that the higher curvatures in general lead to the increased critical buckling load and moreover to the shell‐like behaviour, which result in rather unstable post‐critical behaviour. As for the aspect ratio effect, due to the reduction of the initial stiffness, the higher aspect ratios lead to the drop in buckling load, and thus also lower post‐buckling reserves. On the other hand, the curved panels with low aspect ratio, showed a behaviour similar to the panels with the high curvatures parameters, which is characterized by sudden drop in bearing capacity and huge deflections after the critical load is reached. Furthermore, using the fully non‐linear numerical simulations, the imperfection sensitivity of the curved panels was examined, where, in particular, shape, amplitude and sign of the imperfections were varied. It was concluded that the panels with the higher curvatures as well as the non‐squared panels are more sensitive to the imperfections. Concerning the shape effect, it is more emphasized in case of the panels with the smaller radii, where it may have an impact on the post‐buckling behaviour. Finally, regarding the sign of the imperfections, it was proven that both directions of imperfections have to be verified in order to obtain the most unfavourable behaviour. The sign sensitivity is particularly noticed for the panels which buckle in symmetric buckling mode.
04.10: Analysis of stiffened curved panels in compression: A preliminary numerical study for experimental tests
Authors: Piculin Sara , Sinur Franc , Može Primož 
Published: September 2017

ABSTRACTThe use of different kinds of curved steel panels in bridge design has been increasing in the past few years, but the design recommendations and the knowledge in this field remain scarce. Taking in account the fact that very few experimental tests on life size curved panels have been carried out so far, an experimental study on stiffened and unstiffened curved panels in compression is planned in the near future. For this purpose, a preliminary numerical study on curved panels was conducted, in order to establish an appropriate experimental test setup. This paper deals with a parametric study on stiffened and unstiffened transversally curved steel panels subjected to pure in‐plane compression performing linear buckling analysis (LBA) and fully nonlinear analysis with geometric imperfections (GMNIA). Considering that the shell‐like structures are highly sensitive to initial imperfections, which significantly lowers their ultimate strength, a linear bifurcation analysis is performed first in order to get the buckling modes of the analysed panels. The buckling shapes are later used as equivalent geometric imperfections in the nonlinear analysis, based on the rules given by EN1993‐1‐5. Furthermore, a finite element analysis, considering geometric and material nonlinearity with initial imperfections, is conducted in ABAQUS software. Simply supported, transversally curved and longitudinally stiffened panels are analysed in order to determine their resistance to pure in‐plane compression. A large parametric study is performed to evaluate the effects of different parameters on the ultimate resistance of the panel. Panels that differ in curvature, aspect ratio and stiffness of the stiffeners are studied. Finally, the numerical results of the parametric study on all, the unstiffened, longitudinally stiffened, both curved and flat panels with the same dimensions are compared. Effects of panel curvature on the critical elastic stress and the ultimate resistance are presented.
04.11: Strength enhancement in axially compressed cylinders with stepped walls
Authors: Rotter J. Michael , Al Lawati Hussain 
Published: September 2017

ABSTRACTMetal silos and tanks are subject to loading that increases progressively from the top to the base of the cylindrical shell. Efficient design calls for progressive increases in wall thickness, but metal sheets are made in discrete thicknesses. For silos, buckling under axial compression is the dominant design condition, whilst in tanks axial compression with internal pressure may also be critical. The step increases in wall thickness mean that the most critical point on the wall is always at the base of one strake of uniform thickness, so the location of a critical buckle is expected to be at or just above a change of thickness. Until now, design rules have always ignored the effect of the thicker lower strake in restraining the axial compression buckle above it, and the requirement for buckles to have a finite size.Whilst this effect has previously been noted [1,2], it has never been systematically studied. In this paper, a first thorough study is presented, which shows that the strength enhancement associated with a change of plate thickness can be considerable (over 40%). The presented information addresses the buckling of imperfect shells, and includes both elastic and plastic conditions. The findings are sufficient to produce a modification of the current design rules for buckling under axial compression, giving designers the freedom to extend their thin shell segments deeper in the silo or tank structure.