bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimized Adhesive for Structural Sealant Glazing in Blast Scenarios
Authors: Nardini Viviana , Mueller Ulli
Published: October 2018

Use of silicone adhesives for structural bonding of glass panels to metallic frame is a well‐established technology in façade applications. Selection of silicone technology is mainly driven by the unique UV resistance and thermal stability offered. However, are these the only factors that can drive technology selection in facade applications? Comprehensive experience gained by Sika over the last 50 years for applications in the Transportation Industry proves that polyurethane (PU) technology can offer valuable opportunities also for structural glazing applications in façades, although PU are usually more sensitive to UV radiations. Provided that existing protective measures are implemented to control UV exposure of bond lines, potential of PU technology in facades can be significant. In this paper, mechanical and application properties of Sikaflex®‐268 PU adhesive are presented and compared to Sikasil® SG‐500, a typical silicone used for structural glazing applications in facades. Comparison of mechanical behavior is based on tests performed at different temperatures, after curing as well as after accelerated aging. Results prove outstanding mechanical performance of Sikaflex®‐268 versus Sikasil® SG‐500, making the PU adhesive especially suitable for those systems where needs for transferring high loads exist. In blast scenarios, Sikaflex®‐268 high‐strength performance under highspeed deformations can introduce significant opportunities for joint reduction or for extending design feasibility in critical systems. Benefits offered by Sikaflex®‐268 are not only limited to its mechanical performance but also to the available application solutions. Boostered version of the product exist for both pump equipment and gun dispenser, with two major advantages in façade applications: a) fast curing during production as well as site applications or reglazing b) no limitations in joint dimensions, which confirms the adhesive potential for design in blast scenarios
Novel FRP Glass Elements for Use in the Building Envelope
Authors: Weller Bernhard , Joachim Alina , Wesner Andreas , Wünsch Jan
Published: October 2018

The new element presented here consist of fibre plastic composite and soda‐lime‐silicate glass. It represents a new approach and is technologically different from previous cladding systems. The two materials are bonded permanently without an adhesive. The polymer matrix acts both as a resin in the fibre‐reinforced plastic composite and as an “adhesive” to the glass. The colour of the element is created by adding colouring agents to the matrix.
Translucent wall elements with switchable U‐ and g‐value
Authors: Nestle Nikolaus , Pflug Thibault , Maurer Christoph , Prissok Frank , Hafner Andreas , Schneider Frank
Published: October 2018

This contribution will present a concept for translucent wall elements with switchable U‐value and g‐value. The basic concept of the element consists of an translucent insulation panel (preferably realized by a translucent and light‐guiding foam grid or in the future by transparent vacuum glazing) which is arranged inside a glazed closed cavity in a way that thermally driven convection around the element can either be enabled or suppressed. Suppression of convection is realized by a rollable second insulation which at the same time is reflecting incident solar radiation: If the secondary insulation is fully retracted resulting in high U‐value and g‐value and daylight being guided inside the building. By successively rolling down the insulation, convection can be suppressed and the g‐value can be varied from almost unchanged to almost zero. In the case of the secondary insulation being rolled fully down, the U‐value of the element is also minimal. This state is favourable in a cold winter night or during hot daytime hours in winter. The high translucence, low‐U‐value case is favourable in conditions where solar gains and good insulation are favourable and the translucent high‐U‐value case is favourable when no strong energetic separation of interior and exterior conditions is needed. While the rollable insulation element is a rather delicate structure, it nevertheless can be used as a shading device independent of external wind conditions as it is safely housed inside the glazed wall element. In addition to the concept of the wall element, the need for appropriate building control strategies allowing to make optimal use of the element's potential to save energy for lighting, cooling and heating and demonstrators for various design generations of the element are discussed. Furthermore, the potential for including further functionalities such as harvesting thermal or electrical energy from the element's outer surface is addressed as well.
Structural sealant glazing with architecturally designed photovoltaic modules
Authors: Fath Karoline , Rehde Franziska
Published: October 2018

At the Z3 office‐building of Ed. Züblin AG, in 2017 186 architecturally designed photovoltaic modules with a total capacity of approximately 30 kWp have been integrated in the south façade, replacing the existing structural sealant glazing without visible mechanical fasteners. In this paper, the architectural and structural process for this challenging construction project is presented. One focus lays on mechanical tests for the qualification of the module interlayer performed at TU Dresden, which in future construction projects can support the approval procedure for the installation of structural sealant glazing without mechanical fixtures up to a height of 18 m.
Testing Procedure and the Effect of Testing Machinery on Four‐Point Bending of Curved Glass
Authors: Bukieda Paulina , Engelmann Michael , Weller Bernhard
Published: October 2018

The paper presents a method to determine the bending strength of thermally curved glass with the four‐point bending test, which was developed during the research project PRÜFgbGLAS at Technische Universität Dresden. The test procedure as well as the calculative evaluation closely refers to the EN 1288‐3, which defines the determination of the bending strength of flat glass. However, with curved glass specimens, parameters like the bending radius or the chord length, as well as a practical realisation in the industry have to be taken into account. During the project over 360 specimens were tested with recording the strain at the tensions side and the input force. The examined glass thickness ranged from 3 mm to 12 mm and the bending radii from 400 mm to 2000 mm. Besides, four specimens were tested non‐destructively on different testing machineries in collaboration with four specialists from the glass bending industry. This article gives a practical overview over the application of the new aspects to perform a four‐point bending test on a thermally curved glass specimen. It describes the specimen measurement and the modification of the test rig for testing small bending radii. Further, it presents the results of the additional tests on different testing machineries and discuss the deviation of results, which may occur with the new procedure.
The geometrical properties of random 2D Voronoi tesselations for the prediction of the tempered glass fracture pattern
Authors: Pourmoghaddam Navid , Kraus Michael A. , Schneider Jens , Siebert Geralt
Published: October 2018

This paper presents spatial statistical investigations of randomly generated 2D Voronoi tessellations of planar point distributions for the prediction of the fracture pattern of thermally tempered glasses. Statistical distributions of geometrical characteristics of two dimensional Voronoi cells for three types of point processing in the plane of homogeneous Poisson point process (HPP), Matérn Hard‐Core point process (MHCP) and Strauss point process (SP) are numerically obtained based on the computer experiments. In this paper, required parameters of the point processes are presented. Samples of Voronoi cells in two dimensional spaces are generated from the point distributions. The generated random Voronoi tessellations are examined for their uniformity in comparison to a regular honey comb with hexagonal cells. The statistical distributions of geometrical characteristics, the cell area, the cell perimeter and the number of edges per cell are presented for each of the three point processes.
Dimensioning of Elastic Adhesive Joints with Complex Geometries?
Authors: Scherer Thomas , Wittwer Wolfgang , Scherer Christian , Semar Ernst
Published: October 2018

The current European standard for dimensioning silicone adhesive joints in structural glazing applications is defined in the ETAG 002. Although there are several decades of field experience with this standard it still has some major limitations and mainly uses an empirical concept based on an average force by area engineering approach. In addition there are a number of other restrictions for example the limitation of specific substrates and rectangular shaped joints with defined aspect ratios as well as the exclusion of joints with non‐coplanar surfaces. The presented investigations are based on a combined numerical and experimental concept and demonstrate that appropriately designed elastic adhesive joints with complex geometries excluded by common standards can be evaluated and validated in a systematic and reliable way. The experimental test may easily be combined with well‐established and proven aging test schemes, for which long‐term reliable field experience is available. In addition any desired safety factor can be added.
Glass Bow for the Iran Mall in Tehran
Authors: El Hayek Ibrahim , Stimpfle Bernd , Sendelbach Michael
Published: October 2018

In the North West of Tehran, one of the largest business centres in the Middle East, the Iran Mall, is actually built. It consists of areas for business, sports and cultural activities, and of a large hotel complex. This hotel is dominated by a huge glazing façade rising on the north and the south side almost 100 m up and connecting both lateral façades with a long glazing roof. The glass panes are attached to hybrid system, consisting of horizontal steel frames and prestressed vertical tension rod systems. The roof area consists of Vierendeel frames and circular tubes, with prestressed tension rods in‐between, to support the glazing. This paper is about the central glazing element, the Glass Bow. It describes the design process, analysis and detail design, as well as fabrication, logistics and installation. Parameter studies have been carried out to develop the tension system. Seismic interaction with the main building was taken into account. Glass and supporting structure have been developed to comply with local regulations, and local climatic condition.
Well‐Defined Alkyne Metathesis Catalysts: Developments and Recent Applications
Authors: Ehrhorn Henrike , Tamm Matthias
Published: October 2018

Although alkyne metathesis has been known for 50 years, rapid progress in this field has mostly occurred during the last two decades. In this article, the development of several highly efficient and thoroughly studied alkyne metathesis catalysts is reviewed, which includes novel well‐defined, in situ formed and heterogeneous systems. Various alkyne metathesis methodologies, including alkyne cross‐metathesis (ACM), ring‐closing alkyne metathesis (RCAM), cyclooligomerization, acyclic diyne metathesis polymerization (ADIMET), and ring‐opening alkyne metathesis polymerization (ROAMP), are presented, and their application in natural product synthesis, materials science as well as supramolecular and polymer chemistry is discussed. Recent progress in the metathesis of diynes is also summarized, which gave rise to new methods such as ring‐closing diyne metathesis (RCDM) and diyne cross‐metathesis (DYCM).
{FeNO}7‐Type Halogenido Nitrosyl Ferrates: Syntheses, Bonding, and Photoinduced Linkage Isomerism
Authors: In‐Iam Areenan , Wolf Markus , Wilfer Claudia , Schaniel Dominik , Woike Theo , Klüfers Peter
Published: October 2018

Mononitrosyl–iron compounds (MNICs) of the Enemark–Feltham {FeNO}7 type can be divided into a doublet (S=1/2) and a quartet (S=3/2) spin variant. The latter relies on weak‐field co‐ligands such as amine carboxylates. Aqua‐only co‐ligation appears to exist in the long‐known “brown‐ring” [Fe(H2O)5(NO)]2+ cation, which was prepared originally from ferrous salts and NO in sulfuric acid. A chloride variant of this species, the green [FeCl3(NO)]− ion, was first prepared analoguosly by using hydrochloric instead of sulfuric acid. As a tetrahedral species, it is the simple prototype of sulfur‐bonded {FeNO}7 (S=3/2) MNICs of biological significance. Although it has been investigated for more than a century, neither clean preparative routes nor reliable structural parameters were available for the [FeCl3(NO)]− ion and related species such as the [FeCl2(NO)2]− ion, a prototypical dinitrosyliron species (a “DNIC”). In this work, both issues have been resolved. In addition, we report on a computational study on the ground‐ and excited‐state properties including an assignment of the chromophoric transitions. Photoinduced metastable isomers were characterised in a combined experimental and computational approach that resulted in the confirmation of a single photoinduced linkage isomer of the paramagnetic nitrosyl–metal coordination entity.
Postfunctionalization of Tris(pyridyl) Aluminate Ligands: Chirality, Coordination, and Supramolecular Chemistry
Authors: García‐Romero Álvaro , Plajer Alex J. , Álvarez‐Miguel Lucía , Bond Andrew D. , Wright Dominic S. , García‐Rodríguez Raúl
Published: October 2018

Invited for the cover of this issue is Raúl García‐Rodríguez and co‐workers at Universidad de Valladolid and University of Cambridge. The image depicts the formation of a chiral‐at‐aluminium aluminate by the stepwise reaction of two different alcohols and it is a tribute to the oneiric worlds of surrealist painter René Magritte. Read the full text of the article at 10.1002/chem.201803342.
Chemoselectivity of Tertiary Azides in Strain‐Promoted Alkyne‐Azide Cycloadditions
Authors: Svatunek Dennis , Houszka Nicole , Hamlin Trevor A. , Bickelhaupt F. Matthias , Mikula Hannes
Published: October 2018

The strain‐promoted alkyne‐azide cycloaddition (SPAAC) is the most commonly employed bioorthogonal reaction with applications in a broad range of fields. Over the years, several different cyclooctyne derivatives have been developed and investigated in regard to their reactivity in SPAAC reactions with azides. However, only a few studies examined the influence of structurally diverse azides on reaction kinetics. Herein, we report our investigations of the reactivity of primary, secondary, and tertiary azides with the cyclooctynes BCN and ADIBO applying experimental and computational methods. All azides show similar reaction rates with the sterically non‐demanding cyclooctyne BCN. However, due to the increased steric demand of the dibenzocyclooctyne ADIBO, the reactivity of tertiary azides drops by several orders of magnitude in comparison to primary and secondary azides. We show that this chemoselective behavior of tertiary azides can be exploited to achieve semiorthogonal dual‐labeling without the need for any catalyst using SPAAC exclusively.
Electrochemical and adsorption behaviour of Li+, Na+, K+, Ca2+, and Mg2+ in LiMn2O4/λ‐MnO2 structures
Authors: Liu Dong‐Fan , Sun Shu‐Ying , Yu Jian‐Guo
Published: October 2018

Manganese dioxide ion‐sieves are known to be highly efficient lithium adsorbents, owing to their high adsorption capacity and selectivity. However, their manganese dissolution rate during acid desorption is high. Therefore, electrically switched ion exchange (ESIX) was proposed to recover Li+ from brine. Cyclic voltammetry results indicated that ESIX could be applied to capture lithium from the Li+‐containing solutions. Besides, the electrochemical behaviour of Li+ in LiMn2O4/λ‐MnO2 structures was studied, wherein Na+, K+, Ca2+, and Mg2+ naturally coexisted with Li+ in the brine. No redox peaks were observed between 0.3–1.2 V in the MCl solution (MCl = NaCl, KCl, CaCl2, and MgCl2), and the positions of the redox peaks in the LiCl solution were similar to those in the LiCl and MCl mixed solution, indicating that Na+, K+, Ca2+, and Mg2+ barely interacted with the λ‐MnO2 electrode under the experimental conditions. Based on the experimental results, the Li+ adsorption capacity was determined to be ∼2 mmol · g−1, and the selectivity coefficients of Li+ for Na+, K+, Ca2+, and Mg2+ were 38.78, 35.63, 29.04, and 120.08, respectively. Furthermore, by using ESIX, the Li+ adsorption capacity of the λ‐MnO2 electrode was 82.8 % of its initial value after 50 adsorption‐desorption cycles. Thus, we concluded that ESIX involving an λ‐MnO2 electrode can be used to separate Li+ from brine with excellent selectivity coefficients.
Inhibition of Human Topoisomerase II by N,N,N‐Trimethylethanammonium Iodide Alkylcarbazole Derivatives
Authors: Saturnino Carmela , Caruso Anna , Iacopetta Domenico , Rosano Camillo , Ceramella Jessica , Muià Noemi , Mariconda Annaluisa , Bonomo Maria Grazia , Ponassi Marco , Rosace Giuseppe , Sinicropi Maria Stefania , Longo Pasquale
Published: October 2018

Chemotherapy is used for the treatment of all stages of breast cancer, including the metastatic stage of the disease. Treatment regimens are generally tailored for each patient′s particular situation. However, chemotherapeutic agents are the leading cause of serious drug‐related adverse effects; moreover, drug resistance often occurs. In this study, we designed and synthesized a new series of N‐alkylcarbazoles derived from ellipticine, an alkaloid with a carbazole skeleton initially used in the treatment of metastatic breast cancer and later dismissed because of poor aqueous solubility and severe side effects. After evaluating the binding modes of our class of newly synthesized compounds with human topoisomerase II (hTopo II), we performed hTopo II decatenation assays, identifying compound 4 f (2‐(4‐((3‐chloro‐9H‐carbazol‐9‐yl)pentyl)piperazin‐1‐yl)‐N,N,N‐trimethylethanammonium iodide) as a good inhibitor. Moreover, 4 f and 4 g (2‐(4‐((3‐chloro‐9H‐carbazol‐9‐yl)hexyl)piperazin‐1‐yl)‐N,N,N‐trimethylethanammonium iodide) showed a good anti‐proliferative activity toward breast cancer cells, causing apoptosis by activation of the caspase pathway. Interestingly, the activity of these two compounds on triple‐negative MDA‐MB‐231 cells, which tend to be highly metastatic and aggressive, is strictly connected to the observed inhibition of hTopo II.
Fully automatic model‐based segmentation and classification approach for MRI brain tumor using artificial neural networks
Authors: Arunkumar N. , Mohammed Mazin Abed , Mostafa Salama A. , Ibrahim Dheyaa Ahmed , Rodrigues Joel J.P.C. , de Albuquerque Victor Hugo C.
Published: October 2018

The accuracy of brain tumor diagnosis based on medical images is greatly affected by the segmentation process. The segmentation determines the tumor shape, location, size, and texture. In this study, we proposed a new segmentation approach for brain tissues using MR images. The method includes three computer vision fiction strategies which are enhancing images, segmenting images, and filtering out non ROI based on the texture and HOG features. A fully automatic model‐based trainable segmentation and classification approach for MRI brain tumour using artificial neural networks to precisely identifying the location of the ROI. Therefore, the filtering out non ROI process have used in view of histogram investigation to avert the non ROI and select the correct object in brain MRI. However, identification the tumor kind utilizing the texture features. A total of 200 MRI cases are utilized for the comparing between automatic and manual segmentation procedure. The outcomes analysis shows that the fully automatic model‐based trainable segmentation over performs the manual method and the brain identification utilizing the ROI texture features. The recorded identification precision is 92.14%, with 89 sensitivity and 94 specificity.
MASA‐OpenCL: Parallel pruned comparison of long DNA sequences with OpenCL
Authors: de Figueiredo Marco Antonio C. , de Oliveira Sandes Edans F. , Rodrigues Genaina N. , Teodoro George L. M. , de Melo Alba Cristina M. A.
Published: October 2018

Biological sequence comparison is often used as an auxiliary task in the analysis of genetic material. Pairwise comparison algorithms like Smith‐Waterman evaluate two strings representing sequences of proteins, DNA or RNA to obtain optimal alignment between them. Many applications have been proposed to address the sequence comparison problem, prioritizing the use of graphics cards and proprietary languages such as CUDA. In this paper, we propose and evaluate MASA‐OpenCL, an OpenCL solution for comparing long DNA sequences that is based on the MASA sequence alignment framework, with pruning capability proportional to the similarity of the sequences compared. The results of MASA‐OpenCL were compared to its CUDA counterpart (MASA‐CUDAlign) and, in most cases, MASA‐OpenCL achieved better performance. In order to better understand the behavior of MASA‐OpenCL, we performed a statistical analysis considering 11 comparisons of sequences with high, medium and low similarity in 4 GPUs. As a result, we obtained a multiple linear regression model that considers (a) the sizes of the sequences, (b) the similarity between them, (c) the computational power of the GPU, and (d) the GPU memory bandwidth. We used this model to predict the performance in two other GPUs, with low error rates.
Establishing the Transitory Existence of Amorphous Phases in Crystallization Pathways by the CLASSIC NMR Technique
Authors: Hughes Colan E. , Williams P. Andrew , Kariuki Benson M. , Harris Kenneth D. M.
Published: October 2018

With the growing realization that crystallization processes may evolve through a sequence of different solid forms, including amorphous precursor phases, the development of suitable in‐situ experimental probes is essential for comprehensively mapping the time‐evolution of such processes. Here we demonstrate that the CLASSIC NMR (Combined Liquid‐ And Solid‐State In‐situ Crystallization NMR) strategy is a powerful technique for revealing the transitory existence of amorphous phases during crystallization processes, applying this technique to study crystallization of dl‐menthol and l‐menthol from their molten liquid phases. The CLASSIC NMR results provide direct insights into the conditions (including the specific time period) under which the molten liquid phase, transitory amorphous phases and final crystalline phases exist during these crystallization processes.
Clinical Probes and Endogenous Biomarkers as Substrates for Transporter Drug‐Drug Interaction Evaluation: Perspectives From the International Transporter Consortium
Authors: Chu Xiaoyan , Liao Mingxiang , Shen Hong , Yoshida Kenta , Zur Arik A. , Arya Vikram , Galetin Aleksandra , Giacomini Kathleen M. , Hanna Imad , Kusuhara Hiroyuki , Lai Yurong , Rodrigues David , Sugiyama Yuichi , Zamek‐Gliszczynski Maciej J. , Zhang Lei ,   on behalf of the International Transporter Consortium
Published: October 2018

Drug transporters can govern the absorption, distribution, metabolism, and excretion of substrate drugs and endogenous substances. Investigations to examine their potential impact to pharmacokinetic (PK) drug‐drug interactions (DDIs) are an integral part of the risk assessment in drug development. To evaluate a new molecular entity as a potential perpetrator of transporters, use of well characterized and/or clinically relevant probe substrates with good selectivity and sensitivity are critical for robust clinical DDI assessment that could inform DDI management strategy in the product labeling. The availability of endogenous biomarkers to monitor transporter‐mediated DDIs in early phases of clinical investigations would greatly benefit downstream clinical plans. This article reviews the state‐of‐the‐art in transporter clinical probe drugs and emerging biomarkers, including current challenges and limitations, delineates methods and workflows to identify and validate novel endogenous biomarkers to support clinical DDI evaluations, and proposes how these probe drugs or biomarkers could be used in drug development.
Pharmacokinetics and Transplacental Transfer of Fluoxetine Enantiomers and Their Metabolites in Pregnant Women
Authors: Carvalho Daniela Miarelli , Lanchote Vera Lucia , Filgueira Gabriela Campos de Oliveira , Nardotto Glauco Henrique Balthazar , Duarte Geraldo , Cavalli Ricardo Carvalho , Moisés Elaine Christine Dantas
Published: October 2018

Considering that fluoxetine (FLX) is used to treat depressive states during pregnancy and that it is a cytochrome P450 (CYP)2D6 inhibitor, which is involved in the metabolism of both of its enantiomers, this study aims to describe the enantioselective distribution and metabolism of FLX and of its metabolite norfluoxetine (NorFLX) following a single oral dose. Nine healthy pregnant women received 20 mg FLX at 32 weeks of gestation and later at the day of delivery. The apparent clearance of (S)‐(+)‐FLX (1.45 vs. 0.66 L/hour/kg) and the area under the plasma concentration vs. time curve (AUC) of the (S)‐(+)‐NorFLX (AUC0–∞ 942.7 vs. 498.6 ng hour/mL) were higher (P < 0.05) than those of the respective (R)‐(−) enantiomers, indicating that the (S)‐(+)‐FLX enantiomer is preferentially metabolized to (S)‐(+)‐NorFLX. The placental transfer (umbilical vein/maternal vein) of FLX and NorFLX is low (30–40%), with the predominant transfer of (S)‐(+)‐FLX (44 vs. 33%). The distribution of the enantiomers of FLX and NorFLX to amniotic fluid is low (< 10%).
Inorganic Nanomaterials for Restoration of Cultural Heritage: Synthesis Approaches towards Nanoconsolidants for Stone and Wall Paintings
Authors: Girginova Penka I. , Galacho Cristina , Veiga Rosário , Santos Silva António , Candeias António
Published: October 2018

The synthesis of inorganic nanostructured materials for the consolidation of stone and wall paintings is reviewed. To begin, a description of the methods most commonly used to prepare nanoconsolidants is provided, particularly in the frame of colloid chemistry. Some concepts of the carbonation mechanism as well as the transport properties of some of these materials are addressed. An overview of the synthesis methods together with some of the application particularities of the distinct consolidants are presented thereafter. Furthermore, the requisites for efficient consolidants and some drawbacks of the nanoconsolidants are discussed.
Metal‐Free Route to Precise Synthesis of Poly(propylene oxide) and Its Blocks with High Activity
Authors: Zhang Cheng‐Jian , Duan Han‐Yi , Hu Lan‐Fang , Zhang Cheng‐Hui , Zhang Xing‐Hong
Published: October 2018

The fast and living ring‐opening polymerization (ROP) of propylene oxide (PO) by metal‐free catalysis is reported. By using triethyl borane (TEB) and organic Lewis bases (LBs, e.g.: phosphazene base, amidine and guanidine) as the catalysts, various alkyl alcohols can effectively initiate the ROP of PO, yielding tailor‐made poly(propylene oxide)s (PPOs) with high regioregularity, predictable molecular weights, and narrow dispersity approaching Poisson distribution. The TEB/LB catalysts present unprecedentedly high activity (turnover frequency of up to 7500 h−1) and a truly living character for the polymerization, as evidenced by kinetic studies that showed fast initiation and growth, unobserved chain‐transfer to PO, chain extension reactions, and the synthesis of various PPO‐based block copolymers with narrow dispersities (Đ<1.1).
STWSN: A novel secure distributed transport protocol for wireless sensor networks
Authors: Dvir Amit , Ta Vinh‐Thong , Erlich Sefi , Buttyan Levente
Published: October 2018

Several transport protocols for wireless sensor networks (WSNs) have been designed to fulfill efficiency requirements such as energy and reliability. Unfortunately, most of these transport protocols do not include sufficient security mechanisms and hence are vulnerable to numerous reliability and energy attacks. To address these vulnerabilities, this paper proposes a novel secure transport protocol, named as secure transport protocol for wireless sensor networks (STWSN). On the basis of distributed transport for sensor networks (DTSN) protocol, our protocol adds a new security extension in order to provide secure transport protocol. We provide both informal and formal security analyses of STWSN and show that it resists attacks on energy efficiency and reliability requirements. Last but not least, a performance analysis and simulation results are also presented.
A secure channel code‐based scheme for privacy preserving data aggregation in wireless sensor networks
Authors: Lakshmi V.S. , Deepthi P.P.
Published: October 2018

Data aggregation is an efficient method to reduce the energy consumption in wireless sensor networks (WSNs). However, data aggregation schemes pose challenges in ensuring data privacy in WSN because traditional encryption schemes cannot support data aggregation. Homomorphic encryption schemes are promising techniques to provide end to end data privacy in WSN. Data reliability is another main issue in WSN due to the errors introduced by communication channels. In this paper, a symmetric additive homomorphic encryption scheme based on Rao‐Nam scheme is proposed to provide data confidentiality during aggregation in WSN. This scheme also possess the capability to correct errors present in the aggregated data. The required security levels can be achieved in the proposed scheme through channel decoding problem by embedding security in encoding matrix and error vector. The error vectors are carefully designed so that the randomness properties are preserved while homomorphically combining the data from different sensor nodes. Extensive cryptanalysis shows that the proposed scheme is secure against all attacks reported against private‐key encryption schemes based on error correcting codes. The performance of the encryption scheme is compared with the related schemes, and the results show that the proposed encryption scheme outperforms the existing schemes.
Communication emitter individual identification via 3D‐Hilbert energy spectrum‐based multiscale segmentation features
Authors: Han Jie , Zhang Tao , Qiu Zhaoyang , Zheng Xiaoyu
Published: October 2018

Specific emitter identification can detect emitters automatically by extracting and analyzing features. A novel specific emitter identification method based on 3D‐Hilbert energy spectrum‐based multiscale segmentation (3D‐HESMS) is proposed. First, the time‐frequency energy spectrum is derived via the Hilbert‐Huang transform, that is, a complicated curved surface in a 3D space, namely, the 3D‐Hilbert energy spectrum. The differential box dimension, multifractal dimension, lacunarity change rate, and 3D‐Hilbert energy entropy are extracted to compose the feature vector under multiscale segmentation using fractal theory. Subsequently, communication emitter individual identification is obtained using the 4 features. Finally, the performance and complexity of the 3D‐HESMS method are compared with those of 2 existing methods. Experiments show that the performance of the 3D‐HESMS method is better than those of the 2 other methods. The extracted features with high stability, sufficiency, and identifiability can overcome the negative effects of the changes in signal‐to‐noise ratio and the number of training samples.
Continuous glucose monitoring defined glucose variability is associated with cardiovascular autonomic neuropathy in type 1 diabetes
Authors: Jun Ji Eun , Lee Seung‐Eun , Lee You‐Bin , Ahn Ji Yeon , Kim Gyuri , Hur Kyu Yeon , Lee Moon‐Kyu , Jin Sang‐Man , Kim Jae Hyeon
Published: October 2018

Background

The purpose of this study was to establish the association between continuous glucose monitoring (CGM)‐defined glycaemic variability (GV) and cardiovascular autonomic neuropathy (CAN) in type 1 diabetes independent of mean glucose and to examine the relative contribution of each internationally standardized CGM parameter to this association.

Materials and methods

This study included 80 adults with type 1 diabetes who underwent 3‐day CGM and autonomic function tests within 3 months. The degree of association between internationally standardized CGM parameters and CAN, defined as at least two abnormal parasympathetic tests or the presence of orthostatic hypotension, were analysed by logistic regression, receiver operating characteristics (ROC), and dominance analysis.

Results

A total of 36 subjects (45.0%) were diagnosed with CAN. When adjusted with mean glucose and clinical risk factors of CAN, standard deviation, coefficient of variation, mean amplitude of glycaemic excursion, percent time in level 1 (glucose 54‐69 mg/dL) and level 2 (glucose < 54 mg/dL) hypoglycaemia, area under the curve in level 2 hypoglycaemia, low blood glucose index, high blood glucose index, and percent time in glucose 70 to 180 mg/dL were independently associated with CAN. Multivariable ROC analysis and dominance analysis revealed the highest relative contribution of percent time in level 2 hypoglycaemia to the independent associations between CGM parameters and presence of CAN.

Conclusions

CGM‐defined GV was associated with CAN independent of mean glucose in adults with type 1 diabetes. Among internationally standardized CGM parameters, those describing the degree of level 2 hypoglycaemia were the most significant contributors to this association.
Biased estimation of trends in cohort effects: the problems with age‐period‐cohort models in ecology
Authors: Pigeon Gabriel , Loe Leif Egil , Albon Steve D. , Bonenfant Christophe , Elston David A. , Justin Irvine R. , Ropstad Erik , Veiberg Vebjørn , Stien Audun
Published: October 2018

Environmental variation can generate life‐long similarities among individuals born in the same breeding event, so‐called cohort effects. Studies of cohort effects have to account for the potentially confounding effects of current conditions (observation year) and age of individuals. However, estimation of such models is hampered by inherent collinearity, as age is the difference between observation year (period) and cohort year. The difficulties of separating linear trends in any of the three variables in Age‐Period‐Cohort (APC) models are the subject of ongoing debate in social sciences and medicine but have remained unnoticed in ecology. After reviewing the use of APC models, we investigate the consequences of model specification on the estimation of cohort effects, using both simulated data and empirical data from a long‐term individual‐based study of reindeer in Svalbard. We demonstrate that APC models are highly sensitive to the model's treatment of age, period and cohort, which may generate spurious temporal trends in cohort effects. Avoiding grouping ages and using environmental covariates believed to be drivers of temporal variation reduces the APC identification problem. Nonetheless, ecologists should use caution, given that the specification issues in APC models may have substantial impacts on estimated effect sizes and therefore conclusions.
Synthesis of Peptide–Adenine Conjugates as a New Tool for Monitoring Protease Activity
Authors: Masurier Nicolas , Soualmia Feryel , Sanchez Pierre , Lefort Valérie , Roué Mia , Maillard Ludovic T. , Subra Gilles , Percot Aline , El Amri Chahrazade
Published: October 2018

We took advantage of the powerful adenine SERS (Surface Enhanced Raman Spectroscopy) probe to design peptide–adenine conjugates as candidates for use as serine protease substrates. Whereas the direct introduction of the peptide sequence on the adenine exocyclic N6 amine gave an imidazopurinone derivative, the introduction of an aminoethyl linker between the adenine group and the peptide chain led to the expected candidate probes. These potential substrates were then evaluated for monitoring the hydrolytic activity of trypsin, used as a model protease, by HPLC and by SERS. We demonstrated that the Boc–VPR–adenine conjugate is a substrate of trypsin and constitutes a good starting point to design optimized substrates to monitor protease activity by SERS.
Evaluation of Radical Scavenging Capacity of Polyphenols Found in Natural Malaysian Honeys by Voltammetric Techniques
Authors: Ismail Norjihada Izzah , Sornambikai Sundaram , Kadir Mohammed Rafiq Abdul , Mahmood Nasrul Humaimi , Zulkifli Razauden Mohamed , Shahir Shafinaz
Published: October 2018

As minor constituents present in natural honey, polyphenols have the capacity as antioxidant by donating electron to halt detrimental actions of free radicals. The present work aims to analyze the electrochemical behaviour of polyphenols identified in Malaysian Apis and Trigona honey samples, determine and compare their reducing strengths as well as qualitatively evaluate the radical scavenging capacity of these phenolics in Malaysian honey samples. Six flavonoids, eight phenolic acids, and tannin pentagalloyl glucose (PGG) dissolved in 0.1 M PBS pH 7 were studied by cyclic voltammetry (CV). Seventeen Malaysian honey samples were analyzed using differential pulse voltammetry (DPV). Cyclic voltammograms revealed that polyphenols with catechol moiety in their structure exhibited Ep1a at low potentials, ranging between +0.173 V and +0.404 V. PGG and quercetin may have equal tendency to donate electron (same Ep1a) but higher peak current was observed for the former indicates its higher reducing strength, suggesting PGG as the strongest antioxidant among studied polyphenols. From DP voltammograms, oxidation of honey phenolics occurred in all honey samples with predominant catechol‐bearing peak P1 observed in nanas N1, kelulut K3 and tualang T1 honeys. The varied peak current intensities observed for P1‐P3 in all analyzed Malaysian honey samples suggested that these honey samples can act against free radicals at varying degree and thus are good sources of natural antioxidants.
Multiplexed Immunosensing Platform Coupled to Hybridization Chain Reaction for Electrochemical Determination of MicroRNAs in Clinical Samples
Authors: Jirakova Ludmila , Hrstka Roman , Campuzano Susana , Pingarrón Jose M. , Bartosik Martin
Published: October 2018

There is an urgent need for development of rapid and inexpensive techniques for detection of microRNAs (miRNAs), which are potential biomarkers of various types of cancer. In this paper, we describe a multiplexed electrochemical platform for determination of three cancer‐relevant miRNAs: miR‐21, let‐7a and miR‐31. The strategy combines the use of magnetic beads (MBs) modified with a commercial antibody for the efficient capture of the heteroduplexes formed by hybridization of the target miRNA with DNA probe. Free non‐hybridized region of the DNA probe was thereafter hybridized with two biotin‐labeled auxiliary DNA probes in a process of hybridization chain reaction (HCR), resulting in a long hybrid bearing a large number of biotin molecules. Labeling of these multiple biotin units with streptavidin‐peroxidase conjugates allowed an amplification of the amperometric signal measured after capturing the modified MBs at a screen‐printed carbon electrode array of eight electrodes. The combined strategy demonstrated in a similar assay time significantly higher sensitivity than those previously described using modified MBs with the same capture antibody (without amplification by HCR) or a HCR strategy implemented on the surface of MBs, respectively. The methodology exhibits a good selectivity for discriminating single mismatches and was applied to the determination of the three target miRNAs in total RNA (RNAt) extracted from various cancer cell lines and from cervical precancerous lesions.
Trends in Abundance and Fishing Mortality of American Eels
Authors: Kahn Desmond M
Published: October 2018

A range of findings on the status of American Eels Anguilla rostrata has been published. The most extreme report occurred in 2014, when the International Union for the Conservation of Nature placed the species on its Red List, meaning that the Union considered it endangered. The trend in abundance of American Eels is consequently of concern for conservation biology and fishery management. Here, I present a new index of American Eel relative abundance in the estuarine waters along the U.S. Atlantic coast from 1981 through 2014, consisting of the total American Eel catch per trip by recreational anglers. Abundance was highest in 1981 and then declined through 1995 to about one-sixth of the 1981 value. By 2003, abundance began an irregular increase; by 2014, it was approximately one-half of the 1981 value. Combining commercial landings with the index of relative abundance produces the trend in fishing mortality, which has been relatively low during both the period of declining abundance and the period of increasing abundance, although it increased temporarily during the period of lower abundance from 1995 through 2002. I include a discussion of the Atlantic States Marine Fisheries Commission's 2012 stock assessment and explore some general issues in stock assessment of American Eels.
High Temperature Polymer Electrolyte Membrane Fuel Cells – On the Way to Commercial Maturity
Authors: Cerri Isotta , Heinzel Angelika , Bele Petra , Bucheli Olivier
Published: October 2018

No abstract.
Examining the associations between performance based and ratings of focused attention in toddlers: Are we measuring the same constructs?
Authors: Acar Ibrahim H. , Frohn Scott , Prokasky Amanda , Molfese Victoria J. , Bates John E.
Published: October 2018

The study examines the concurrent and longitudinal associations between ratings‐based measures (parents, secondary caregivers, and observers) and performance‐based measures of focused attention in toddlers aged 30 (n = 147), 36 (n = 127), and 42 months (n = 107). Parents and secondary caregivers rated focused attention behaviours using the Children's Behaviour Questionnaire and observers rated toddlers' focused attention during a series of laboratory tasks using the Leiter‐R Examiner Rating Scale. Toddlers' behaviours on three structured tasks (Token Sort, Toy Play, and Lock Box) were used to assess their performance‐based focused attention in a laboratory setting. Correlations show that parent ratings are not related to observer and teacher ratings or to the performance‐based measures at all ages tested. Second, based on confirmatory factor analyses, a single factor explains the common variance between indicators when the parent ratings are not included in the models. The single factor shows measurement invariance between ages 36 and 42 months based on factor structure, relations of indicators to the factor, and factor scale over time. Third, indicators of focused attention at age 30 months do not seem to measure a common, coherent factor. Interpretations of similarities and differences between ratings and performance‐based indicators of focused attention and the presence of a focused attention construct are discussed.

Highlights

The concurrent and longitudinal association between ratings and performance‐based attention was examined.

Parent‐ratings, observer‐ratings, and performance‐based attention via structured tasks were used.

Parent ratings of attention were not related to other ratings, or to the performance‐based measures at all ages; a single factor explains the common variance between indicators when the parent ratings are not included in the models; indicators of focused attention at age 30 months do not seem to measure a common, coherent factor.
Volatility spillovers between real exchange rate returns and real stock price returns in Malaysia
Authors: Wong Hock Tsen
Published: October 2018

This study analyses volatility spillovers between real exchange rate returns and real stock price returns in Malaysia. The component‐generalized autoregressive conditional heteroskedasticity model with asymmetric effect is used to decompose volatility into permanent or long‐run component and transitory or short‐run component. Permanent and transitory components of volatility are commonly high in the global financial crisis, 2008. The results of the seemingly unrelated regressions framework show that volatility spillovers of permanent component between real exchange rate returns and real stock price returns are stronger than volatility spillovers of transitory component between real exchange rate returns and real stock price returns. Moreover, volatility spillovers of permanent and transitory components between real Malaysian ringgit against the U.S. dollar return and real stock price returns are stronger than real Malaysian ringgit against the Japanese yen exchange rate return and real stock price returns. There is some evidence of Granger causality between real exchange rate returns and real stock price returns. On the whole, there is some evidence of the link between the exchange rate market and the stock market in Malaysia.
Domestic lead arranger certification and the pricing of project finance loans
Authors: Ahiabor Frederick S. , James Gregory A.
Published: October 2018

Using a sample of 1,270 project finance syndicated loan tranches arranged from 1998 to 2011 and worth over $300 billion, we estimate the causal impact of certification by domestic lead arrangers on the pricing of project finance loans in emerging markets. We hypothesize that, on average, domestic arrangers are better able to structure and screen project finance deals, credibly communicate the true value of a project and its underlying network of contracts, and monitor the loan contract compared with foreign arrangers. If so, all things being equal, domestic arranger certification should result in lower loan spreads compared with foreign arranger certification. Our results support this hypothesis. After controlling for project and loan characteristics and the potential endogeneity of the lead arranger's selection, we find that certification by domestic arrangers causes a significant reduction in loan spreads across different industrial categories and geographic locations of projects. This finding demonstrates the economic value of domestic arranger certification in project finance lending. Our results suggest that, in the presence of information asymmetry between project sponsors and participant lenders in the syndicate, certification by domestic arrangers offers a superior mechanism to minimize search, information, and monitoring costs.
Comparison of the metabolism of 10 chemicals in human and pig skin explants
Authors: Géniès C. , Jamin E. L. , Debrauwer L. , Zalko D. , Person E. N. , Eilstein J. , Grégoire S. , Schepky A. , Lange D. , Ellison C. , Roe A. , Salhi S. , Cubberley R. , Hewitt N. J. , Rothe H. , Klaric M. , Duplan H. , Jacques‐Jamin C.
Published: October 2018

Skin metabolism is important to consider when assessing local toxicity and/or penetration of chemicals and their metabolites. If human skin supply is limited, pig skin can be used as an alternative. To identify any species differences, we have investigated the metabolism of 10 chemicals in a pig and human skin explant model. Phase I metabolic pathways in skin from both species included those known to occur via cytochrome P450s, esterases, alcohol dehydrogenases and aldehyde dehydrogenases. Common Phase II pathways were glucuronidation and sulfation but other conjugation pathways were also identified. Chemicals not metabolized by pig skin (caffeine, IQ and 4‐chloroaniline) were also not metabolized by human skin. Six chemicals metabolized by pig skin were metabolized to a similar extent (percentage parent remaining) by human skin. Human skin metabolites were also detected in pig skin incubations, except for one unidentified minor vanillin metabolite. Three cinnamyl alcohol metabolites were unique to pig skin but represented minor metabolites. There were notable species differences in the relative amounts of common metabolites. The difference in the abundance of the sulfate conjugates of resorcinol and 4‐amino‐3‐nitrophenol was in accordance with the known lack of aryl sulfotransferase activity in pigs. In conclusion, while qualitative comparisons of metabolic profiles were consistent between pig and human skin, there were some quantitative differences in the percentage of metabolites formed. This preliminary assessment suggests that pig skin is metabolically competent and could be a useful tool for evaluating potential first‐pass metabolism before testing in human‐derived tissues.