bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Study on the Fatigue Assessment Concepts for Horizontal Butt Welds of Wind Turbine Towers
Authors: Spüntrup Hendrik Schulze , Rauch Marion , Knobloch Markus
Published: September 2019

This paper presents a comparative study on the fatigue life prediction of different fatigue assessment methods. The nominal stress concept, the local stress concept and a two‐stage‐model, which consists of the strain‐life approach and the crack propagation method are applied to compute the fatigue life of horizontal butt welds and to assess the methods capability to provide adequate prognosis of fatigue life of wind turbine towers. The comparative study shows the impact of weld imperfections on the fatigue life according to the local stress concept and the strain‐life approach. The later approach even considers the influence of actual geometry and imperfection on the total damage sum. The approach has a great potential to accurately predict the fatigue life of butt welds and notch details of wind turbine structures with precise manufacturing, sophisticated processes and high‐quality control.
FE Simulation of High Frequency Mechanical Impact (HFMI) Treatment – First Results
Authors: Gkatzogiannis Stefanos , Knoedel Peter , Ummenhofer Thomas
Published: September 2019

High Frequency Mechanical Impact treatment is investigated numerically in the present paper. A first‐step numerical dynamic analysis is carried out using the solver LS‐Dyna. The treatment of an unnotched component of S355 is simulated. The strain rate dependent material parameter Cowper‐Symonds is calibrated for the investigated material based on data from literature. Goal of the present analysis is to act a first step for a robust engineering approach, which will calculate with sufficient preciseness the residual stresses introduced by this post‐weld treatment. The calculated residual stresses of the present investigation are compared with respective measurements found in literature. Deviation between measured and simulated residual stresses indicates the need for further improvement of the present model.
State‐of‐the‐Art Framework for Structural Design of Offshore Wind Jacket Foundations
Authors: Nielsen Martin Bjerre , Jensen Jacob Fisker , Harper Christopher , Knudsen Lennart Skovbjerg , Pedersen Ronnie Refstrup
Published: September 2019

A state‐of‐the‐art framework for design of jacket foundations for offshore wind turbines is presented. It is illustrated how an efficient, yet highly accurate structural model can be achieved by a combination of a comprehensive beam finite element model and more detailed shell/solid finite element models, where the former suffices for representing the overall global behaviour, while the latter improve the representation of non‐trivial structural details such as the transition piece and tubular joints. Hereby the verification of the majority of the structural elements according to various design codes can be automated on beam element level, while the fatigue performance via the hot‐spot method as well as detailed stress and buckling analysis for relevant joints and details can be performed based on the detailed shell/solid finite element models readily available for stiffness representation. This computational framework ensures consistency between the local and global description levels and an efficient cloud interface facilitates the thousands of design load cases that typically requires consideration for a full detailed design to be simulated within a reasonable amount of time.
A consistent approach for flexural and lateral torsional buckling as basis for a general buckling curve
Authors: Feldmann Markus , Nonn Jonas , Heinemeyer Christoph
Published: September 2019

Chapter 6.3.4 of EN 1993‐1‐1 (1) deals with the General Method for the verification of stability problems of in‐plane loaded frames or beams. For the general case of having combined moment and normal force the method provides two different approaches to determine the reduction factor for out‐of‐plane buckling. They accord to the special case of lateral torsional buckling (“LTB” – i.e. with moment only) and flexural buckling (“FB” – i.e. with normal force only) on the other hand. However, in general cases this produces inconsistencies leading to conflicts with the intended generality of the formulation and finally to incorrect results. Because the individually combined effect of the in‐plane actions My and N are the reason for the out‐of‐plane instability. This requires a reduction considering the individual load combination. To find a solution for this, the in‐plane‐ and out‐of‐plane effects can be put together in a general formulation to obtain a buckling curve for combined moment and normal force ensuring consistency with the buckling curves of the special cases. By this the choice of buckling curves in Eurocode 3 clause 6.3.4 (1) can be improved.
New stability design methodology through overall linear buckling analysis
Authors: Szalai József , Papp Ferenc
Published: September 2019

Two new stability design methods are presented: the Overall Strength Reduction Method (OSRM) and the Overall Imperfection Method (OIM). Both methods are based on the linear buckling analysis (LBA) of global structural models and use the standard reduction curves. The OSRM is formulated in the classic way using generalized slenderness and reduction factors while the OIM uses equivalent amplitude for the buckling mode based geometrical imperfection. It is shown that both methods have the same mechanical background which is built on two essential components: (1) the generalized form of an Ayrton‐Perry (or Perry‐Robertson) type strength reduction method for basic reference members and (2) a generalized transformation technique connecting the real members of the global structural model with the proper basic reference member. The first component is a mechanically consistent extension of the model behind the traditional buckling curves used only for specific stability cases like flexural buckling of columns or lateral‐torsional buckling of beams so far. The second component can be regarded as the generalization of the well‐known effective length approach. The new design methods cover all types of buckling modes (flexural, torsional, flexural‐torsional, lateral‐torsional or any interaction), which can be calculated by LBA of structural models composed of uniform or non‐uniform members with arbitrary cross‐sections and support conditions and subjected to any complex loading (e.g. biaxial bending with moment gradient, direct torsion effects etc.). There is no need for any additional input for the calculations (like effective length factors, unrestrained lengths of beams, moment gradient factors, equivalent length for the imperfection amplitude etc.) since all the necessary information is received from the elastic critical load and buckling mode shape. This paper clarifies the mechanical interpretation and proper calculation of all the components of the two methods and shows some comprehensive validation study on the performance.
Influence of Slenderness Ratio on the Buckling Behaviour of Curved Panels in Pure Shear
Authors: Van Staen Gilles , De Backer Hans , Van Bogaert Philippe
Published: September 2019

Curved steel plates are commonly used in aerospace and naval engineering, using very thin plates in order to create lightweight structures. In recent years, the use of this kind of plates is extended towards bridge design, with several examples in Belgium. Since bridges have to carry larger loads, the thicknesses of these plates increase up to several centimetres. The decreased plate slenderness influences the buckling behaviour of the plates, leading to elastoplastic buckling. Multiple finite element models are created to investigate the buckling response of these plates. A single plate with simply supported and clamped supported edges are subjected to pure shear. The parameters used are the plate thickness and the curvature ratio in order to have a large spectrum of stability influence. Results show that for the perfect plates the buckling behaviour changes with increasing curvature. With the use of the American Specifications AISI and their specifications for flat plate thicknesses, new rules are determined to predict the buckling behaviour for all kinds of curved panels.
Experimental behaviour of stainless steel cellular beam in fire
Authors: Malaska Mikko , Cashell Katherine , Alanen Mika , Mela Kristo , Afshan Sheida
Published: September 2019

This paper presents a description and the analysis of a fire test on a cellular beam made from grade 1.4301 stainless steel. Cellular beams are increasingly popular in the construction as they provide a structurally and materially efficient design solution as well as allowing the passage of services. In addition, stainless steel is also increasing in popularity for structural applications owing to its inherent durability and ductility, as well as other attractive properties such as structural efficiency and low maintenance requirements. However, the behaviour of stainless steel cellular beams in fire has received little attention from the research community until recently. In the current paper, a description is presented of an experimental investigation into the fire behaviour of grade 1.4301 stainless steel cellular beams. The experimental arrangements are described together with the details of the specimen. The test occurred at the fire testing laboratory at Tampere University, Finland. For the member test, the beam spanned 4,3 m, with an overall depth of 290 mm and 200 mm diameter openings along the span. It was found that the unprotected beam lasted for 29 minutes during the test, after being exposed to a standard fire, and the experiment was eventually stopped due to excessive rate of deflection. The test specimen has been analysed using available design methods and the results are presented herein.
Guidance for Preloading of Stainless Steel Bolting Assemblies using a Bolt Tightening Qualification Procedure
Authors: Stranghöner Natalie , Jungbluth Dominik , Abraham Christoph
Published: September 2019

In modern steel constructions the use of stainless steel becomes more important, especially in corrosive environments where stainless steel is superior to carbon steel. So far, the use of stainless steel bolting assemblies for preloading in those constructions is not permitted according to EN 1090‐2 and EN 1993‐1‐4, unless all necessary parameters for a secure preloading are defined in a procedure test on a case by case basis. The treatment of preloaded stainless steel bolting assemblies as special fasteners is based on the lack of knowledge on the preloading and time‐dependent behaviour. Stainless steel tends to creep and relaxation. Furthermore, stainless steel bolting assemblies are susceptible to galling under high contact pressures which are achieved during the preloading process. It was always assumed, that these effects make a secure and efficient preloading of these types of bolting assemblies impossible. Besides that, it was in general questioned, if the resulting surface pressures of bolting assemblies according to EN ISO 4014 and EN ISO 4017 are acceptable for steel structures. Nevertheless, the construction industry highly demands the use of these types of bolting assemblies, especially when bolted connections have to be installed in corrosive environments, which was why the initiated European RFCS research project SIROCO also considered preloaded bolted connections made of stainless steels.

The present paper summarizes the investigations into preloaded bolted connections made of stainless steel carried out in the frame of SIROCO. Furthermore, a guidance is given for the necessary procedure tests in form of a Bolt Tightening Qualification Procedure (BTQP) for the determination of reliable tightening parameters, considering the tightening method, a secure tightening process and the inspection criteria.
Simplified Bending Capacity Formulation Based on the Continuous Strength Method
Authors: Molkens Tom , Rossi Barbara
Published: September 2019

In the frame of the current revision of the Eurocodes, there is a trend to simplify the existing design formulae while, at the same time, providing higher efficiency and reliability. To consider the effect of strain hardening present in the material behaviour of stainless steel, advanced design formulae are proposed in the 4th edition of the Design Manual for Structural Stainless Steel. The method called the continuous strength method (CSM), is a deformation‐based design approach that uses a bilinear hardening material model, leading to the introduction of several new parameters depending on which stainless steel family is considered and one additional design formula for the cross‐section verification. The CSM was proven to be accurate for austenitic, duplex and ferritic grades.

The idea developed in the present paper is that there exists a reasonable and equally accurate approximation of the cross‐section capacity considering hardening through the combination of the elastic and plastic section modulus. The concept uses the current well‐known plastic section modulus and, to deal with the hardening effect, an additional contribution is added for which an equation is proposed. This equation only combines the elastic section modulus, the yield‐to‐ultimate strength ratio as well as their difference. Then, the cross section bending resistance is determined through well‐known cross‐section geometrical parameters.

The presented approach is compared to the formulation of the CSM for I‐section and rectangular hollow sections beams, for austenitic, duplex and ferritic grades. It is shown to be only slightly more conservative for hollow sections. The formulation deals with tangible concepts, is easy to apply for daily engineering practice and guarantees a more rational use of the material benefit.
AMAGERVÆRKET BIO4: A steel building with a remarkable facade made of tree logs
Authors: Ramsussen Torben , Arndt Casper Højgaard , Nordestgaard Peter Madsen
Published: September 2019

Copenhagen has an ambition to become the first CO2 neutral capital in the world by 2025. The utility company HOFOR that provides district heating for 500.000 Copenhagen residents are therefore converting the heat and energy production at Amagerværket from coal to sustainable biomass.

For the main building complex, this comes into play with the use of hanging tree logs and a garden at roof level. The façades of the main building complex consists of an inner layer of golden steel sandwich panels and an outer layer of tree trunks in full building height. The tree trunks are supported on the steel superstructure using an external secondary steel support system. On the northern façade, which is facing the city, the tree trunks are more prominent, as it consists of more layers of tree trunks and includes a stairway going up between the trunks to the viewing platform on top of the building. This part will be open for the public with features allowing the public to be educated about the BIO plant.

The public access to the viewing platform gives special challenges for robustness and fire demands, but also for dynamic load and comfort for both the support system for tree logs, the stairway, and the cantilevered platform.

For the facade with hanging tree logs there are supplementary challenges with, aesthetics, durability, structural use of wood logs and development of static supporting system, natural loading, as well as fabrication and erection, incl. mock up for testing the system.

Modularity of the system is designed into this, so that there will be sets with large number of identical “boxes” that can be placed with variation throughout the facade giving a visual variation in the hanging tree logs but insuring the modularity for fabrication and erection.

3,500 tons of steel makes all this happen.
The Gate to Gellerup, Aarhus, Denmark: Steel structures substitute part of concrete building
Authors: Nordestgaard Peter Madsen , Graa Kenneth , Borbjerggaard Kenneth H.
Published: September 2019

The Gate to Gellerup is one of the first pilot projects in the ambition Master Plan of Gellerupparken. The new innovative solution of constructions creates a new expression and opportunity to connect Aarhus to Gellerup. Not only does the new Gate improve the connection between areas, the new Gate also allows the inhabitants to pass though the building, as the road runs through the building

The stairway no. 44 in the block of flats – B4, fig. 1, has been elevated of the ground, to establish the new Infill project. The Infill project contains three stories of flats and a separate stair‐/elevator tower.

In order to maintain the architectural expression of the block and of the flats, and due to the long span of the Infill structure as well as a restriction of maximum thichness of the floor slabs, the existing concrete structure has been replaced by a steel structure, as steel is the only feasible material to obtain slender architectural expression.

The aim of the steel design was to find a synthesis of architecture, structural behaviour, productivity and buildability. Structural integrity is achieved by extensive analysis using 3D finite element software and the productivity and buildability was achieved by using simple connections and a continuous focus on easy assembly. The project has been designed by use of Tekla 3D‐model software.

The steel structure has been designed in a way, which allows the contractor to assemble the whole steel structure on the ground and then hoist it in place as one assembly. This method was developed in order to achieve optimized period of installation on site.
Experimental and Software Analysis of Composite Action in Steel‐Concrete Composite Bridges with Continuous Shear Connectors
Authors: Kvočák Vincent , Kožlejová Viktória , Dubecký Daniel , Kanishchev Ruslan , Vaňová Patrícia
Published: September 2019

Twentieth century brought a lot of forward‐moving inventions. In the field of bridges and structural engineering we could witness the birth of the first steel‐concrete composite bridges and their rapid development. In 1985, the perforated steel strips were officially introduced to the eyes of researchers by a patent from Wolfhardt Andrä. Encased in concrete to make composite bridges they have several advantages – low construction height, lower usage of steel in comparison with embedded I‐beams, etc. In practise, they are mainly used as short railway bridges due to their practicality during the construction works. Nowadays, many research groups all around the world focus on improving the above mentioned invention by tuning the geometry of the strips as well as the concrete dowels to increase its composite action. Such research is also currently running at the Technical University of Košice, Faculty of Civil Engineering, which developed five perforated steel strip types. The specimens are tested at Laboratory of Excellent Research and are modelled in software for finite element analysis (ABAQUS) to simulate the performed tests.
Influence of the execution parameters on the welds of high‐strength steels
Authors: Stroetmann Richard , Kästner Thoralf
Published: September 2019

The mechanical properties of welded joints are significantly influenced by the execution parameters. Within the scope of the ongoing AiF‐FOSTA research project P1020 dilatometer examinations and tests on welded joints using a new test specimen were carried out. Thermomechanically rolled and quenched fine‐grained structural steels were examined. Based on these examinations, regression models were developed to assess the mechanical properties of the heat‐affected zone as a function of the cooling time t8/5. In addition, the mechanical properties of welds with filler metals G35, G42 and G79 were examined and statistically evaluated. The results provide the basis for further development of the execution rules and a new design approach for welded joints on high‐strength steels.
Finite Element Analyses of Cold‐formed Stainless Steel Beam with Web Openings in Shear
Authors: Fareed Ishqy , Somadasa Wanniarachchi , Poologanathan Keerthan , Gunalan Shanmuganathan , Corradi Marco , Sivapalan Sivaram
Published: September 2019

In the recent years, an increase in the use of stainless steel in the construction industry has been witnessed, more specifically in exposed architectural applications and where total life economics, durability, improved resistance to aggressive environment etc. are prime deciding criteria. However, limited research has been undertaken on the shear behaviour and strength of cold‐formed stainless steel beam with web openings. Hence a numerical study was undertaken to investigate the shear behaviour and strength of cold‐formed stainless steel with web openings. Finite element models of simply supported cold‐formed stainless steel Lipped Channel Beams with web openings were developed under a mid‐span load. They were then validated with currently available shear test results and further used in a detailed parametric study. In this research, both stocky and slender cross‐sections were considered. The ultimate shear capacities from finite element analyses confirmed that currently available design equations are inadequate to determine the shear capacities of stainless steel beams with web openings. Hence improved design equations were developed for the shear capacity of cold‐formed stainless steel beams with web openings. This paper presents the details of this numerical study of cold‐formed stainless steel beams with web openings, and the results..
Finite Element Analyses of Cold‐formed Stainless Steel Beams Subject to Shear
Authors: Dissanayake Madhushan , Poologanathan Keerthan , Gunalan Shanmuganathan , Tsavdaridis Konstantinos Daniel , Nagaratnam Brabha
Published: September 2019

Stainless steel is a high‐performance construction material that combines the strength and stiffness associated with ferrous alloys with the corrosion resistance derived principally from the high chromium content. Its unique combination of properties usually comes at a cost, which puts increased emphasis on ensuring that the material is utilized to the upmost in structural applications. Consequently, in the recent years, an increase in the use of stainless steel in the construction industry has been witnessed, more specifically in exposed architectural applications and where total life economics, durability, improved resistance to aggressive environment, etc. are prime deciding criteria. However, the shear behaviour and capacity of cold‐formed stainless steel beams has not been investigated adequately in the past. Hence, detailed finite element analyses (FEA) were undertaken to investigate the shear behaviour and strength of stainless steel lipped channel beams (LCBs). The developed finite element models were first validated using the shear test results. They were then used in a detailed parametric study to investigate the effects of various influential parameters such as section thickness, depth and grade. Moreover, a parametric study was conducted to emphasize the beneficial effect of strain hardening of stainless steel on shear capacity of LCBs, in particularly for compact sections. FEA results showed that currently available design equations (EN1993‐1‐4) are inadequate to capture the available inelastic reserve capacity of compact stainless steel LCBs, thus suitable equations were proposed to enhance the predictions. This paper presents the details of finite element modelling and analyses of stainless steel LCBs and the development of these new shear design rules.
Increasing incidence of Epstein‐Barr virus–related nasopharyngeal carcinoma in the United States
Authors: Argirion Ilona , Zarins Katie R. , Ruterbusch Julie J. , Vatanasapt Patravoot , Sriplung Hutcha , Seymour Erlene K. , Rozek Laura S.
Published: September 2019

Background

The incidence of nasopharyngeal carcinoma (NPC) has been historically low in the United States. Although etiological factors differ by histological subtype, Epstein‐Barr virus is accepted as the primary risk factor for nonkeratinizing NPC. In light of the changing epidemiology of viral‐associated cancers, it is important to evaluate the temporal incidence of NPC in the United States.

Methods

Incidence and survival data from 1973 through 2015 were obtained from the Surveillance, Epidemiology, and End Results program. Stratified analyses were conducted to assess temporal trends in NPC by histological subtype, sex, and race. The data were analyzed using SAS and Joinpoint Regression Software to determine age‐adjusted incidence rates, determine trends in the annual percent change, and calculate 5‐year relative survival estimates and Kaplan‐Meier curves.

Results

Although overall NPC incidence is decreasing in the United States, the nonkeratinizing differentiated subtype is starkly increasing, with an annual percent change of approximately 4% among white males (95% CI, 2.5%‐5.2%), white females (95% CI, 1.9%‐6.2%), and black males (95% CI, 2.0%, 5.7%); 2.7% among black females (95% CI, 0.8%, 4.6%); and 1.8% among women in the “other” race category (95% CI, 0.4%‐3.3%). Racial disparities were noted, with 32% of nonkeratinizing NPC cases among blacks occurring before the age of 40 years. In addition, black males displayed consistently worse survival across all histological subtypes, whereas individuals in the “other” race category, particularly females, experienced the highest 5‐year relative survival estimates.

Conclusions

The current results indicate that the Epstein‐Barr virus–related, differentiated NPC subtype is increasing across all sexes and races in the United States, with distinct incidence and survival disparities among blacks.
Real‐time action feature extraction via fast PCA‐Flow
Authors: Chen Huafeng , Li Hongyang , Xu Zengmin , Zhao Yunhong , He Tigang
Published: September 2019

Action recognition is a research hotspot in the field of Internet of Things (IoT). Currently, local pixel‐domain spatiotemporal feature extraction methods have reached the state‐of‐the‐art action recognition performance on many challenging datasets. However, the poor computational complexity of these approaches prevents them from scaling up to real‐time applications. For solving this problem, we present a novel real‐time video feature extraction technique by exploiting the fast PCA‐Flow algorithm. Firstly, we down‐sample video images in form of grid. Based on the down‐sampling images, PCA‐Flow algorithm is used to calculate optical flow among adjacent images. The PCA‐Flow matrices are then expanded to the original video image size by using efficient gCLSR super‐resolution method to keep the inherent geometric structure of the optical flow. Finally, we compute action descriptors based on original pixel frames and the enlarged PCA‐Flow images. The proposed approach is validated on three challenging datasets: UCF50, Hollywood2, and HMDB51. Experimental results indicate that the proposed method is more efficient in computation and can achieve competitive quality than the state‐of‐the‐art methods.
Systematic review of congestion handling techniques for 802.11 wireless networks
Authors: Mishra Haribansh , Gupta Ratneshwer , Upadhyay Satyanshu Kumar
Published: September 2019

IEEE 802.11 is a matured standard for wireless local area networks (WLANs). The cellular network providers had made every possible effort to offload their traffic over WLANs whenever it was possible, owing to the benefits that this technology provides. IEEE 802.11 is gaining greater prominence with the arrival of 802.11ax standard, which is backed by the Wi‐Fi alliance by branding as Wi‐Fi 6. The issue of congestion has been studied well for various networks. Particularly, in wireless networks, it needs to be tackled in a peculiar manner owing to the uncertain nature of the wireless medium. This study explores and evaluates the improvements done at various protocol layers to handle the problem of congestion in 802.11‐based wireless networks. An attempt is made to understand the implication of different parameters and the significance of cross‐layer interaction. Further, an endeavor is made to assess the influence on congestion control mechanisms in the different architectures of 802.11 networks. Lastly, the challenges that might be confronted at different protocol layers, while dealing with the issue of congestion, are classified.
Editorial to the virtual issue highlighting neuroscience based research in eating disorders to mark the 49th Society for Neuroscience Annual Meeting
Authors: Frank Guido K. W.
Published: September 2019

Objective

This virtual issue of the International Journal of Eating Disorders highlights recently published research that is based on neuroscience concepts, to mark the 49th Society for Neuroscience Annual Meeting in Chicago, IL, in November 2019.

Methods and Results

The collection of articles includes research published between 2018 and 2019 that fall within the broader field of clinical neuroscience. Those articles span a broad range of themes, including food intake regulation and reward circuitry, taste perception, decision‐making, cognitive and emotional bias, and targeting altered brain circuits using novel therapeutic methods.

Discussion

The eating disorders field as a whole is increasingly incorporating neuroscience‐based concepts when studying those disorders and developing disease models. We hope that this virtual issue will further stimulate discussion and research that is focused on brain circuits and neurobiology to study etiology and pathophysiology of eating disorders to develop more effective treatments.
Seagrass‐associated fungal communities show distance decay of similarity that has implications for seagrass management and restoration
Authors: Wainwright Benjamin J. , Zahn Geoffrey L. , Zushi Joshua , Lee Nicole Li Ying , Ooi Jillian Lean Sim , Lee Jen Nie , Huang Danwei
Published: September 2019

Marine fungal biodiversity remains vastly understudied, and even less is known of their biogeography and the processes responsible for driving these distributions in marine environments. We investigated the fungal communities associated with the seagrass Enhalus acoroides collected from Singapore and Peninsular Malaysia to test the hypothesis that fungal communities are homogeneous throughout the study area. Seagrass samples were separated into different structures (leaves, roots, and rhizomes), and a sediment sample was collected next to each plant. Amplicon sequencing of the fungal internal transcribed spacer 1 and subsequent analysis revealed significant differences in fungal communities collected from different locations and different structures. We show a significant pattern of distance decay, with samples collected close to each other having more similar fungal communities in comparison with those that are more distant, indicating dispersal limitations and/or differences in habitat type are contributing to the observed biogeographic patterns. These results add to our understanding of the seagrass ecosystem in an understudied region of the world that is also the global epicenter of seagrass diversity. This work has implications for seagrass management and conservation initiatives, and we recommend that fungal community composition be a consideration for any seagrass transplant or restoration programme.
Light environment drives the shallow‐to‐mesophotic coral community transition
Authors: Tamir Raz , Eyal Gal , Kramer Netanel , Laverick Jack H. , Loya Yossi
Published: September 2019

Light quality is a crucial physical factor driving coral distribution along depth gradients. Currently, a 30 m depth limit, based on SCUBA regulations, separates shallow and deep mesophotic coral ecosystems (MCEs). This definition, however, fails to explicitly accommodate environmental variation. Here, we posit a novel definition for a regional or reef‐to‐reef outlook of MCEs based on the light vs. coral community–structure relationship. A combination of physical and ecological methods enabled us to clarify the ambiguity in relation to the mesophotic definition. To characterize coral community structure with respect to the light environment, we conducted wide‐scale spatial studies at five sites along shallow and MCEs of the Gulf of Eilat/Aqaba (0–100 m depth). Surveys were conducted by technical‐diving and drop‐cameras, in addition to one year of light spectral measurements. We quantify two distinct coral assemblages: shallow (<40 m) and MCEs (40–100 m), exhibiting markedly different relationships with light. The depth ranges and morphology of 47 coral genera were better explained by light than depth, mainly, due to photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) (1% at 76 and 36 m, respectively). Branching coral species were found mainly at shallower depths, that is, down to 36 m. Among the abundant upper‐mesophotic specialist corals, Leptoseris glabra, Euphyllia paradivisa, and Alveopora spp. were found strictly between 40 and 80 m depth. The only lower‐mesophotic specialist, Leptoseris fragilis, was found deeper than 80 m. We suggest that shallow coral genera are light‐limited below a level of 1.25% surface PAR and that the optimal PAR for mesophotic communities is at 7.5%. This study contributes to moving MCE ecology from a descriptive phase into identifying key ecological and physiological processes structuring MCE coral communities. Moreover, it may serve as a model enabling the description of a coral zonation worldwide on the basis of light quality data.
Habitat coupling mediates trophic cascades in an aquatic community
Authors: Marklund Maria H. K. , Svanbäck Richard , Eklöv Peter
Published: September 2019

Trophic cascades and other indirect effects can significantly mediate community interactions. Movement of energy between systems has been shown to be important for trophic cascades in food webs, where coupling between habitats can be important for food web stability and species evenness. To investigate the effects of habitat coupling on the stability and dynamics of chlorophyll a (used as a proxy for phytoplankton biomass), mediated by the abundance and composition of zooplankton and macroinvertebrates, we manipulated habitat use by the predator perch. We show a greater indirect effect of predation on phytoplankton abundance when no habitat coupling occurs, indicating a stronger predation effect and a decrease in zooplankton grazing pressure leading to an increase in phytoplankton biomass. Although we found a significant effect on chlorophyll a between the treatments, this effect was not evident in the abundance of prey resources of perch (zooplankton and macroinvertebrates). Other indirect effects, not measured in this study, such as compositional changes in prey groups, could potentially explain the lack of effect in prey resources. While there is a strong theoretical argument for the stabilizing effects of habitat coupling, empirical evidence is scarce. Our study offers tentative support for these theoretical predictions in a natural system.
Investigation of compressed hydrogen refueling process of 60 L type IV tank used in fuel cell vehicles
Authors: Sapre Shitanshu , Pareek Kapil , Rohan Rupesh , Singh Pawan K.
Published: September 2019

Hydrogen fuel cell vehicle provides the significant advantage of high energy conversion efficiency and zero emission. Efficient hydrogen storage methods are vital for successful implementation of the hydrogen‐related technologies. Compressed hydrogen storage has been considered as a promising option in recently commercialized hydrogen fuel cell vehicles. The short filling time and high state of charge of compressed hydrogen storage tank are an essential requirement for fuel cell vehicles. This study presents the detail investigation of refueling compressed storage tank using computational fluid dynamics simulation and heat capacity model. The goal of the simulation is to identify the end temperature and state of charge. Initially, the mathematical model of end temperature and state charge is formulated. Later, the overall heat transfer involved in the refueling process is investigated by heat capacity model based on MC method defined by SAE J2601. The density obtains from the simulation is compared with the National Institute of Standards and Technology database. The SE in simulated results for the state of charge is reduced to <1% after applying the heat capacity method. The results may shade light on better understanding the refueling process of compressed hydrogen storage for fuel cell vehicle.
To Randomize or Not to Randomize? That is the Question
Authors: Boruch Robert , Allen‐Platt Claire , Gerstner Clara‐Christina
Published: September 2019

In this chapter, Robert Boruch, Claire Allen‐Platt, and Clara‐Christina Gerstner explore whether an evaluation that employs a randomized controlled trial is appropriate for the Women Affirming Motherhood program. To make this determination, they focus on the program's clientele and pipeline, how programming is conducted, and what outcomes and effects should be explored. The authors conclude that an exploratory study is necessary before a summative evaluation can be pursued.
Theorists’ Models in Action: A Second Look
Authors: Alkin Marvin C. , Christie Christina A.
Published: September 2019

In recent years, foundations have begun to think more holistically and to support collaboration across organizations. One form of collaboration, and the focus of the case study described in this issue, is the collective impact initiative, where a foundation convenes organizations from different sectors around a shared agenda. But how are evaluations designed in this context? This chapter introduces four theorists who, in this issue, translate their theories into practice to help us answer that question. To provide context for their individual chapters, the Evaluation Theory Tree is used to frame how the theorists were selected and introduce each of them in greater detail.
Using linkage studies combined with whole‐exome sequencing to identify novel candidate genes for familial colorectal cancer
Authors: Toma Claudio , Díaz‐Gay Marcos , Franch‐Expósito Sebastià , Arnau‐Collell Coral , Overs Bronwyn , Muñoz Jenifer , Bonjoch Laia , Soares de Lima Yasmin , Ocaña Teresa , Cuatrecasas Miriam , Castells Antoni , Bujanda Luis , Balaguer Francesc , Cubiella Joaquín , Caldés Trinidad , Fullerton Janice M. , Castellví‐Bel Sergi
Published: September 2019

Colorectal cancer (CRC) is a complex disorder for which the majority of the underlying germline predisposition factors remain still unidentified. Here, we combined whole‐exome sequencing (WES) and linkage analysis in families with multiple relatives affected by CRC to identify candidate genes harboring rare variants with potential high‐penetrance effects. Forty‐seven affected subjects from 18 extended CRC families underwent WES. Genome‐wide linkage analysis was performed under linear and exponential models. Suggestive linkage peaks were identified on chromosomes 1q22–q24.2 (maxSNP = rs2134095; LODlinear = 2.38, LODexp = 2.196), 7q31.2–q34 (maxSNP = rs6953296; LODlinear = 2.197, LODexp = 2.149) and 10q21.2–q23.1 (maxSNP = rs1904589; LODlinear = 1.445, LODexp = 2.195). These linkage signals were replicated in 10 independent sets of random markers from each of these regions. To assess the contribution of rare variants predicted to be pathogenic, we performed a family‐based segregation test with 89 rare variants predicted to be deleterious from 78 genes under the linkage intervals. This analysis showed significant segregation of rare variants with CRC in 18 genes (weighted p‐value > 0.0028). Protein network analysis and functional evaluation were used to suggest a plausible candidate gene for germline CRC predisposition. Etiologic rare variants implicated in cancer germline predisposition may be identified by combining traditional linkage with WES data. This approach can be used with already available NGS data from families with several sequenced members to further identify candidate genes involved germline predisposition to disease. This approach resulted in one candidate gene associated with increased risk of CRC but needs evidence from further studies.
Efficacy of aspirin, prednisone, and multivitamin triple therapy in treating unexplained recurrent spontaneous abortion: A cohort study
Authors: Ou Hua , Yu Qi
Published: September 2019

Objective

To assess the efficacy of aspirin, prednisone, and multivitamin triple therapy in treating unexplained recurrent spontaneous abortion (URSA).

Methods

Data were reviewed from women with early RSA attending a hospital in Beijing, China, 2013–2017. Those with no abnormal indices (e.g., endocrine, coagulation, immune, genetic) were diagnosed as having URSA, and received aspirin, prednisone, and multivitamin therapy (triple therapy group, n=106) or folic acid monotherapy (control group, n=65). Treatment efficacy was evaluated as the rate of successful treatment (12‐week pregnancy with obvious embryo and embryonic heart, nuchal translucency thickness <0.25 cm, size consistent with gestational age, no early malformation).

Results

Overall, 362 women had early RSA and 171 (47.2%) had URSA. The rate of successful pregnancy was similar between the triple therapy (89.6%) and control (92.3%) groups (P=0.343). The rate of successful treatment was higher in the triple therapy (86.3%) than in the control (53.3%) group (P<0.001). In multivariate logistic regression analysis, triple therapy was associated with higher odds of successful treatment, whereas the number of spontaneous pregnancy losses was associated with lower odds of successful treatment.

Conclusion

The triple therapy of aspirin, prednisone, and multivitamin was found to be a good treatment option for women with URSA.
Interventions to improve the use of long‐acting reversible contraceptive methods at primary health centers in Burkina Faso
Authors: Kiemtoré Sibraogo , Zoungrana Zakaria , Zamané Hyacinthe , Kaboré Charles W.P.D. , Ouédraogo Ali , Bonané Blandine
Published: September 2019

Objective

To assess the effects of strengthening family planning capacity on the uptake of long acting reversible contraceptive (LARC) methods at two primary health centers.

Methods

Between April 2016 and March 2017, the Society of Gynecologists and Obstetricians of Burkina Faso (SOGOB) increased the capacity of two primary health centers in Ouagadougou, Burkina Faso, to offer LARC methods by training staff and providing family planning equipment and commodities. Uptake of LARC methods was compared between the year preceding the intervention and the year during the intervention.

Results

Within a year, the number of new users of family planning increased 2.8‐fold from 2936 new users before the intervention to 8267 during it. The rate of new users of contraception increased 1.9‐fold (14.9% vs 28.1%; P<0.001) for all LARC methods, 2.4‐fold for intrauterine contraceptive devices (IUCDs), and 1.7‐fold for subdermal contraceptive implants. The proportion of new users of the copper IUCD younger than 25 years was higher during the intervention than before it (57.2% vs 46.9%; P=0.026).

Conclusion

The SOGOB's family planning intervention resulted in an increase in the use of LARC methods at the two primary health centers.
Response rate correlates with indifference points in a delay‐discounting procedure
Authors: García‐Leal Óscar , Barrón Erick , Camarena‐Pérez Héctor , Vílchez Zirahuén
Published: September 2019

To study how effort affects reward value, we replicated Fortes, Vasconcelos and Machado's (2015) study using an adjusting‐delay task. Nine pigeons chose between a standard alternative that gave access to 4 s of food, after a 10 s delay, and an adjusting‐delay alternative that gave access to 12 s of food after a delay that changed dynamically with the pigeons' choices, decreasing when they preferred the standard alternative, and increasing when they preferred the adjusting alternative. The delay value at which preference stabilized defined the indifference point, a measure of reward value. To manipulate effort across phases, we varied the response rate required during the delay of the standard alternative. Results showed that a) the indifference point increased in the higher‐response‐rate phases, suggesting that reward value decreased with effort, and b) in the higher‐response‐rate phases, response rate in the standard alternative was linearly related to the indifference point. We advance several conceptions of how effort may change perceived delay or amount and thereby affect reward value.
Radiosynthesis and validation of [5‐cyano‐N‐(4‐(4‐[11C]methylpiperazin‐1‐yl)‐2‐(piperidin‐1‐yl)phenyl) furan‐2‐carboxamide] ([11C]CPPC), a PET radiotracer for imaging CSF1R, a microglia‐specific marker
Authors: Mathews William B. , Wu Yunkou , Horti Andrew G. , Naik Ravi , Hall Andrew W. , Holt Daniel P. , Dannals Robert F.
Published: September 2019

In this practitioner protocol, the radiochemical synthesis of [11C]CPPC is described in detail, and a quality control summary of three validation productions is presented. The results indicate that the radiotracer product can be produced in good radiochemical yield (> 60 mCi (2.22 GBq) at end‐of‐synthesis (EOS)), at high specific activity (molar activity > 11,435 mCi/μmole (423 GBq/μmole) at EOS) and high chemical and radiochemical purity. The entire production conforms to current Good Manufacturing Practice (cGMP) requirements. The final product is formulated as a sterile, pyrogen‐free solution suitable for human injection.
Double surfactants‐assisted electromembrane extraction of cyromazine and melamine in surface water, soil and cucumber samples followed by capillary electrophoresis with contactless conductivity detection
Authors: Guo Mengnan , Liu Shiyu , Wang Manman , Lv Yifei , Shi Jialei , Zeng Yuan , Ye Jiannong , Chu Qingcui
Published: September 2019

BACKGROUND

Cyromazine (CYR) and its main degradation product melamine (MEL) are attracting wide attention due to their potential hazards to the environment and humans. In this work, double surfactants‐assisted electromembrane extraction (DS‐EME) by Tween 20 and alkylated phosphate was firstly used for purification and extraction of CYR and MEL, and the extract was directly analyzed by capillary electrophoresis with capacitively coupled contactless conductivity detection.

RESULTS

Under the optimum conditions, two targets could be well separated from the main interferences, including common biogenic amines and inorganic cations within 14 min. This developed method was successfully applied to the analyses of surface water, soil and cucumber samples, and the average recoveries were in the range 93.3–112%. DS‐EME provided a synergistic purification and enrichment effect for CYR and MEL by adding Tween 20 and alkylated phosphate into donor phase and supporting liquid membrane, respectively. Satisfactory limits of detection [0.2–1.5 ng mL−1, signal‐to‐noise ratio (S/N) = 3] could be obtained in the tested sample matrices, and the corresponding enrichment factors were up to 115∼123 times.

CONCLUSION

This developed method provides an alternative for the simultaneous analysis of CYR and MEL in complex real‐world samples. © 2019 Society of Chemical Industry