bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental and numerical study of isotropic circular plates' response to underwater explosive loading, created by conic shock tube
Authors: Heshmati M. , Zamani A J. , Mozafari A.
Published: January 2017

Today, to reduce the cost and increase the safety, test devices like conic shock tube have been widely used to investigate the underwater explosion phenomenon and its impact on structures. A shock tube is designed, manufactured and utilized in the mechanic of explosion laboratory of mechanic faculty of K.N. Toosi University of Technology to study the effect of isotropic metal plates' material in the present study. The source which creates shock in the utilized shock tube is an explosive material and the positive point is that in such a tube a high pressure is produced with a tiny explosive charge. In order to investigate the effect of the material and the geometry of the utilized metal plate, three materials are considered with two different thicknesses in the experimental tests. The behavior of the plate can be measured if the amount of the pressure produced by the explosive charge and the amount of plate's transformation is specified. To present a semi‐experimental equation of the behavior of the plate which is under the explosion loading with the water interface in the experimental tests, numerical simulation is performed with LS‐Dyna software. At the end, by combining the experimental and simulation results, the effect of the material and the thickness changes is studied specifically and an explosive charge is provided by adding weight parameter to anticipate the transformation of these metal plates.
An adaptive sampling method for high‐dimensional shift‐invariant signals
Authors: Jiang Yingchun , Wei Lusong , Chen Guangxi
Published: January 2017

In this paper, an adaptive method for sampling and reconstructing high‐dimensional shift‐invariant signals is proposed. First, the integrate‐and‐fire sampling scheme and an approximate reconstruction algorithm for one‐dimensional bandlimited signals are generalized to shift‐invariant signals. Then, a high‐dimensional shift‐invariant signal is reduced to be a sequence of one‐dimensional shift‐invariant signals along the trajectories parallel to some coordinate axis, which can be approximately reconstructed by the generalized integrate‐and‐fire sampling scheme. Finally, an approximate reconstruction for the high‐dimensional shift‐invariant signal is obtained by solving a series of stable linear systems of equations. The main result shows that the final reconstructed error is completely determined by the initial threshold in integrate‐and‐fire sampling scheme, which is generally very small. Copyright © 2017 John Wiley & Sons, Ltd.
Preparation of Forced Gradient Copolymers Using Tube‐in‐Tube Continuous Flow Reactors
Authors: Saubern Simon , Nguyen Xuan , Nguyen Van , Gardiner James , Tsanaktsidis John , Chiefari John
Published: January 2017

The preparation of forced gradient polymers has received considerable attention using batch reactors, while the preparation of usable quantities of forced gradient copolymers using continuous flow reactors has been hampered by the need to vary the composition of the monomer feedstock continuously during the reaction. A reactor that allows for addition of a monomer feedstock continuously at all points along the length of the reactor tubing allows for the preparation of forced gradient copolymers in continuous flow reactors, allowing for the scale‐up and bulk preparation of these polymers. This study reports here the initial investigation of preparing forced gradient copolymers using the reversible addition–fragmentation chain transfer methodology in tube‐in‐tube continuous flow reactors.

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Spatial Hadamard encoding of J‐edited spectroscopy using slice‐selective editing pulses
Authors: Chan Kimberly L. , Oeltzschner Georg , Schär Michael , Barker Peter B. , Edden Richard A.E.
Published: January 2017

A new approach for simultaneous dual‐voxel J‐difference spectral editing is described, which uses spatially selective spectral‐editing pulses and Hadamard encoding. A theoretical framework for spatial Hadamard editing and reconstruction for parallel acquisition (SHERPA) was developed, applying gradient pulses during the frequency‐selective editing pulses. Spectral simulations were performed for either one (gamma‐aminobutyric acid, GABA) or two molecules (glutathione and lactate) simultaneously detected in two voxels. The method was tested in a two‐compartment GABA phantom, and finally applied to the left and right hemispheres of 10 normal control subjects, scanned at 3 T.

SHERPA was successfully implemented at 3 T and gave results in close agreement with conventional MEGA‐PRESS scans in both the phantom and in vivo experiments. Simulations for GABA editing for (3 cm)3 voxels in the left and right hemispheres suggest that both editing efficiency losses and contamination between voxels are about 2%. Compared with conventional single‐voxel single‐metabolite J‐difference editing, two‐ or fourfold acceleration is possible without significant loss of SNR using the SHERPA method. Unlike some other dual‐voxel methods, the method can be used with single‐channel receiver coils, and there is no SNR loss due to unfavorable receive‐coil geometry factors.
Specification, composition, and placement of network services with flexible structures
Authors: Dräxler Sevil , Karl Holger
Published: January 2017

Network function virtualization and software‐defined networking allow services consisting of virtual network functions to be designed and implemented with great flexibility by facilitating automatic deployments, migrations, and reconfigurations for services and their components. For extended flexibility, we go beyond seeing services as a fixed chain of functions. We define the service structure in a flexible way that enables changing the order of functions in case the functionality of the service is not influenced by this and propose a YANG data model for expressing this flexibility. Flexible structures allow the network orchestration system to choose the optimal composition of service components that, for example, gives the best results for placement of services in the network. When number of flexible services and number of components in each service increase, combinatorial explosion limits the practical use of this flexibility. In this paper, we describe a selection heuristic that gives a Pareto set of the possible compositions of a service as well as possible combinations of different services, with respect to different optimization objectives. Moreover, we present a heuristic algorithm for placement of a combination of services, which aims at placing service components along shortest paths that have enough capacity for accommodating the services. By applying these solutions, we show that allowing flexibility in the service structure is feasible.
An adaptive variational Quasicontinuum methodology for lattice networks with localized damage
Authors: Rokoš O. , Peerlings R. H. J. , Zeman J. , Beex L. A. A.
Published: January 2017

Lattice networks with dissipative interactions can be used to describe the mechanics of discrete meso‐structures of materials such as 3D‐printed structures and foams. This contribution deals with the crack initiation and propagation in such materials and focuses on an adaptive multiscale approach that captures the spatially evolving fracture. Lattice networks naturally incorporate non‐locality, large deformations and dissipative mechanisms taking place inside fracture zones. Because the physically relevant length scales are significantly larger than those of individual interactions, discrete models are computationally expensive. The Quasicontinuum (QC) method is a multiscale approach specifically constructed for discrete models. This method reduces the computational cost by fully resolving the underlying lattice only in regions of interest, while coarsening elsewhere. In this contribution, the (variational) QC is applied to damageable lattices for engineering‐scale predictions. To deal with the spatially evolving fracture zone, an adaptive scheme is proposed. Implications induced by the adaptive procedure are discussed from the energy‐consistency point of view, and theoretical considerations are demonstrated on two examples. The first one serves as a proof of concept, illustrates the consistency of the adaptive schemes and presents errors in energies. The second one demonstrates the performance of the adaptive QC scheme for a more complex problem. Copyright © 2017 John Wiley & Sons, Ltd.
The influence of multiwalled carbon nanotubes‐NiCoAl layered double hydroxide hybrids on fire safety performance of poly(ethylene‐co‐vinyl acetate) composites
Authors: Si Jingyu , Ping Peng , Xie Hongyan , Yang Wei , Lu Hongdian
Published: January 2017

NiCoAl layered double hydroxide (NiCoAl LDH) and multiwalled carbon nanotubes (CNTs) were successfully self‐assembled to generate a three‐dimensional CNTs‐NiCoAl LDH hybrid by means of a urea‐hydrolysis method. The scanning electron microscopy observations revealed that the hybrid was composed of both “core/shell” and flower‐like nanostructure. Composites of poly(ethylenes‐co‐vinyl acetate) (EVA) with CNTs‐NiCoAl LDH were prepared by melt blending. Their flammability performance and smoke toxicity were evaluated. CNTs‐NiCoAl LDH was found to be an efficient additive to improve the flame retardancy of EVA and reduce the smoke toxicity by suppressing the emission of carbon monoxide (CO). The physical properties of the char were believed to be critical in improving the flame retardancy. The remarkable reduction in smoke toxicity of EVA upon CNTs‐NiCoAl LDH was probably attributed to the combined effects of adsorption and catalysis on the oxidation of CO. POLYM. COMPOS., 39:E835–E841, 2018. © 2017 Society of Plastics Engineers
Surface modification of nanohydroxyapatite and its loading effect on polylactic acid properties for load bearing implants
Authors: Michael Feven Mattews , Ratnam Chantara Thevy , Khalid Mohammad , Ramarad Suganti , Walvekar Rashmi
Published: January 2017

Blends of polylactic acid (PLA) and nanohydroxyapatite (NHA) were prepared through melt‐mixing by varying the composition of NHA from 1 to 5 wt%. The tensile properties of the PLA‐1 wt% NHA nanocomposite exhibited higher values than neat PLA. Beyond 1 wt% NHA, a drop in tensile properties of the PLA–NHA nanocomposites was observed due to agglomeration and poor interfacial adhesion between NHA and PLA. Therefore, NHA was surface modified (mNHA) using three different surface modifiers namely, 3‐aminopropyl triethoxysilane (APTES), sodium n‐dodecyl sulfate (SDS) and polyethylenimine (PEI). The surface treatment of NHA was studied through Fourier transform infrared spectroscopy (FTIR) and energy dispersive X‐ray (EDX). Results revealed that the tensile properties increased in order of PLA‐5 wt% mNHA (APTES) followed by PLA‐5 wt% mNHA (SDS), whereas PEI modified NHA resulted in lower tensile properties. Further, increasing mNHA loading to 30 wt%, decreased the tensile strength due to agglomeration of mNHA. POLYM. COMPOS., 39:2880–2888, 2018. © 2016 Society of Plastics Engineers
pH and temperature responsiveness in AgNPs stabilized by a new poly(vinylidene fluoride) random graft copolymer
Authors: Kuila Atanu , Maity Nabasmita , Chatterjee Dhruba P. , Nandi Arun K.
Published: January 2017

Poly(vinylidene fluoride)(PVDF)‐graft‐random copolymers(PD) of diethyleneglycol methylether methacrylate(MeO2MA) and dimethylaminoethyl methacrylate(DMAEMA) are synthesized by a combined atom transfer radical coupling and atom transfer radical polymerization technique at three different co‐monomer compositions. The molar ratio of MeO2MA to DMAEMA in PD are measured to be 1:5.8, 1:1.3, and 1:0.5 for PD1, PD2, and PD3 graft copolymers. In PD2 the feed ratio and mole ratio are same indicating an azeotropic composition causing highest yield (89%) and highest molecular weight (9.29 × 105). The grafted chains of PD are temperature and pH responsive and in basic pH they show a sudden increase in size above certain temperature for LCST‐type phase transition, however, this is not observed at pH 4 and 7. PD can generate AgNPs under UV irradiation and morphology of PD at 30 °C varies with pH from vesicle to nanosphere. The AgNPs lie on the surface of the vesicles or assemble with the PD chains forming nanosphere morphology. At different pH, PD samples exhibit plasmon peaks at different wavelengths attributed to various size, shapes and cluster formation. The UV–vis spectra of AgNPs stabilized by PD1 and PD2 samples exhibits similar LCST‐type phase transition as observed above, but that of PD3 does not show any such transition. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 960–970
Polybenzobisimidazole‐derived two‐dimensional supramolecular polymer
Authors: Seo Wanji , Carpenter Keith L. , Gaugler James A. , Shao Wenting , Werling Keith A. , Fournier Philip M. , Lambrecht Daniel S. , Star Alexander
Published: January 2017

We report a novel crystalline supramolecular polybenzobisimidazole (SP‐PBBI) capable of providing a two‐dimensional polymer (2DSP‐PBBI) by liquid‐phase exfoliation. A regular arrangement of rigid rod‐like polybenzobisimidazole (PBBI) chains is achieved by interchain hydrogen bonding. Titration of 2DSP‐PBBI with cobalt chloride (CoCl2) using UV‐Vis spectroscopy demonstrates the presence of bidentate NO ligands on the PBBI backbone and NO–Co(II) complexation. Imaging analysis using atomic force microscopy (AFM) reveals the planar surface morphology of exfoliated 2DSP‐PBBI sheets with lateral dimensions of <1 μm and thickness of <30 nm. The size of the polymer crystal growth is tuned by employing condensation/precipitation polymerization under nonisothermal conditions. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1095–1101
The IDL of E. coli SSB links ssDNA and protein binding by mediating protein–protein interactions
Authors: Bianco Piero R. , Pottinger Sasheen , Tan Hui Yin , Nguyenduc Trong , Rex Kervin , Varshney Umesh
Published: January 2017

The E. coli single strand DNA binding protein (SSB) is essential to viability where it functions in two seemingly disparate roles: it binds to single stranded DNA (ssDNA) and to target proteins that comprise the SSB interactome. The link between these roles resides in a previously under‐appreciated region of the protein known as the intrinsically disordered linker (IDL). We present a model wherein the IDL is responsible for mediating protein–protein interactions critical to each role. When interactions occur between SSB tetramers, cooperative binding to ssDNA results. When binding occurs between SSB and an interactome partner, storage or loading of that protein onto the DNA takes place. The properties of the IDL that facilitate these interactions include the presence of repeats, a putative polyproline type II helix and, PXXP motifs that may facilitate direct binding to the OB‐fold in a manner similar to that observed for SH3 domain binding of PXXP ligands in eukaryotic systems.
Superparasitism, immune response and optimum progeny yield in the gregarious parasitoid Palmistichus elaeisis
Authors: de S Pereira Kleber , Guedes Nelsa Maria P , Serrão José E , Zanuncio José C , Guedes Raul Narciso C
Published: January 2017

BACKGROUND

The subsequent deposition of an egg clutch by a female parasitoid into a host already parasitised either by itself or a conspecific (i.e. superparasitism) is a counterintuitive adaptive strategy, particularly considering the female parasitoid's ability to recognise the parasitised hosts. Such a scenario suggests that the adaptive value of superparasitism depends on the number of clutches laid in the same host, with consequences for parasitoid progeny yield. Here, we tested whether such is the case for the gregarious parasitoid Palmistichus elaeisis and explored its underlying basis.

RESULTS

Allowing female parasitoids to lay multiple egg clutches in a single melonworm host pupa, parasitoid progeny and fitness exhibited a peak or optimum at three egg clutches laid per host pupa. In addition, haemocyte count, encapsulation and melanisation decreased with the number of egg clutches laid per host pupa.

DISCUSSION

An optimum number of three clutches laid per host pupa was detected for P. elaeisis. As immune response via haemocyte production, encapsulation and melanisation decreased with the number of clutches laid per host, the higher parasitoid yield and fitness observed is the likely consequence of a compromised immune response coupled with an accommodative (i.e. scramble) larval competitive strategy allowing enough resources for optimum balance of parasitoid number and quality produced. © 2017 Society of Chemical Industry
Influence of tropical South Atlantic sea‐surface temperatures on the Indian summer monsoon in CMIP5 models
Authors: Kucharski Fred , Joshi Manish K.
Published: January 2017

In this study the teleconnection from the tropical South Atlantic to the Indian monsoon has been assessed in observations and in 32 models from the World Climate Research Programme (WCRP) Coupled Model Intercomparison Project Phase 5 (CMIP5). All models show that the regression pattern of tropics‐wide Atlantic sea‐surface temperature (SST) anomalies onto the tropical South Atlantic index correlates well with that in observations, even though with varying spatial standard deviations. However, only about half of the 32 models considered show the correct sign of rainfall response over India to a warm anomaly in the south tropical Atlantic, which is a reduction of rainfall. On the other hand, models generally do show large‐scale responses broadly consistent with the observations, and the signal over India depends on relatively subtle changes in the response. This response to a tropical South Atlantic warm (cold) anomaly is a low‐level quadrupole in stream function with an anticyclonic (cyclonic) anomaly over the Arabian Sea and India. This anticyclonic (cyclonic) anomaly leads to a weakening (strengthening) of the Somali jet and low‐level divergence (convergence) over India, both inducing a reduction (an increase) of Indian rainfall. The models which do not show the correct rainfall response over India also show a response similar to the one indicated above, but with maximum of the anticyclonic (cyclonic) response shifted to the western Pacific. The large‐scale Walker circulation adjustment to the tropical South Atlantic SST anomalies is identified as one of the factors which account for the differences in the low‐level stream‐function response. Models (and the observations) with the correct sign of the rainfall signal over India show the dominant upper‐level convergence (divergence) as response to a warm (cold) tropical South Atlantic in the western Pacific region, whereas models with the wrong sign of the rainfall signal show it predominantly in the central‐eastern Pacific. The fact that such relatively subtle changes in the response lead to a reversal of the rainfall signal over India raises the question about the robustness of the tropical South Atlantic–Indian monsoon teleconnection.
Decentralized fault detection and isolation of Markovian jump interconnected systems with unknown interconnections
Authors: Li Li‐Wei , Yang Guang‐Hong
Published: January 2017

This paper investigates the decentralized fault detection and isolation (FDI) problem for Markovian jump interconnected systems with unknown interconnections. Different from the existing decentralized FDI approaches, the requirement for access to operation modes of all subsystems, which is unreasonable and hard to meet in realistic applications, is removed. By utilizing local measurements and neighboring mode information, a decentralized FDI filter is constructed to generate a residual for each subsystem of Markovian jump interconnected system. Then, a new design method is developed such that the resulting augmented system is stochastically stable and the generated residual is sensitive to local fault. In addition, the proposed method can achieve fault detection and isolation simultaneously. Finally, two examples are given to illustrate the effectiveness and merits of the new results. Copyright © 2017 John Wiley & Sons, Ltd.
Surface Mediated Hierarchical Assemblies of Highly Hydrophobic Phenylalanine‐Based Peptides
Authors: Mayans Enric , Fabregat Georgina , Juárez Ruben , Cativiela Carlos , Puiggalí Jordi , Alemán Carlos
Published: January 2017

We report the noticeable control exerted by the surface in the self‐assembly of a highly hydrophobic triphenylalanine peptide with fluorenyl functionalities blocking the two ends. The remarkable differences observed among the polymorphic hierarchical assemblies obtained onto silanized glass, scratched glass, stainless steel, exfoliated mica, silicon wafer, carbon, polytetrafluoroethylene, plasma‐functionalized, polystyrene and nitrocellulose substrates are consequence of the balance between peptide⋅⋅⋅peptide and peptide⋅⋅⋅surface interactions. This balance is greatly influenced by the surface characteristics, as defined by the wettability (hydrophobicity or hydrophilicity) and roughness (degree of flatness and regularity). Furthermore, very stable dendritic structures, in which primary frameworks nucleated from the center grow according to a 4‐fold pseudo‐symmetry branching, have been obtained onto hydrophilic treated polystyrene.
Chloride Platinum(II) Coordination Compounds with4’‐Substituted Terpirydine Ligands as Donor‐Acceptor‐Donor Systems ‐ Structural, Electrochemical and Luminescence Studies.
Authors: Maroń Anna , Czerwińska Katarzyna , Małecki Jan G. , Machura Barbara , Szłapa‐Kula Agata , Krompiec Stanisław
Published: January 2017

Platinum(II) coordination compounds with formulas [PtCl(L)]Cl, (where L=4’‐(2,2’‐bithiophen‐5‐yl)‐2,2′:6′,2”‐terpyridine (L1), 4’‐(4‐dimethylaminophenyl)‐2,2′:6′,2”‐terpyridine (L2),

4’‐(2,4‐difluorophenyl)‐2,2′:6′,2”‐terpyridine (L3)), were synthesized from K2[PtCl4] precursor and characterized by X‐ray crystallography, FT‐IR, NMR, UV‐Vis spectroscopy and electrochemical studies. The emission properties of the compounds were studied in solutions and in solid state at ambient temperature and in methanol : ethanol frozen glass matrix at 77 K. The quantum yields of fluorescence, the lifetimes and the nature of excited states were described on the basis of the molecular properties. Theoretical calculations, with usage of DFT method, were undertaken to elucidate the structural, spectroscopic and bonding properties of the synthesized coordination compounds.
Making the Business Case for Sustainability: How to Account for Intangible Benefits—A Case Study Approach
Authors: Kreiss Cory , Nasr Nabil , Kashmanian Richard
Published: January 2017

Sustainability is continuing to change the way businesses operate. Stakeholders are insisting that corporations implement more responsible business practices, and they are holding them increasingly accountable for their associated environmental and social impacts. Research has provided significant contributions toward sustainability‐related tools and best practices, allowing sustainability to be integrated even farther across business operations. However, challenges still exist, preventing many companies from fully integrating sustainability. Although intangible benefits are not commonly included in business case assessments, such benefits can be derived through sustainability initiatives and may offer additional value in evaluating the business case for sustainability. In this article, we review current literature on accounting methods for the business case for sustainability as well as currently available methods or tools that are capable of estimating intangible benefits. In addition, we use case studies to illustrate if, and how, companies are accounting for intangible benefits, and we identify best methods for accounting for intangible benefits.
Development of Zinc Oxide Sensors for Detecting Ammonia Gas in the Ambient Air: A Critical Short Review
Authors: Chatterjee Bappaditya , Bandyopadhyay Amitava
Published: January 2017

Ammonia (NH3) is emitted into the atmosphere by various industries and other sources and causes environmental pollution. Considering the hazards of ammonia, detecting leakage from vessels and pipes demands the use of sensors. Therefore, the development of NH3 gas sensors assumes considerable importance to researchers and regulators and to industry, businesses, and facilities that make, store, or use ammonia. The use of metal oxide sensors (MOS) for detecting NH3 gas, such as zinc oxide (ZnO), has been a topic of interest to researchers seeking methods to detect NH3 gas, even at low concentrations. In this article, an attempt has been made to review the research thus far published on the synthesis of ZnO‐based NH3 gas sensor materials, their characterization, and analyses of their performance. Finally, we make several recommendations regarding the scope of future research. For example, the kinetics of the sensor materials should

be determined. Furthermore, extensive studies of gas–solid (NH3–ZnO) adsorption are proposed to ascertain the exact adsorption mechanism in terms of isotherm, kinetics, and diffusive mass transport, and to determine “reversibility” and “recovery” of sensor materials so they can continue sensing and activating alarms when necessary for practical applications.
A multi‐anchoring approach in mobile IP networks
Authors: Wang You , Bi Jun , Jiang Xiaoke
Published: January 2017

Many recent mobility solutions, including derivatives of the well‐known Mobile IP as well as emerging protocols employed by future Internet architectures, propose to realize mobility management by distributing anchoring nodes (Home Agents or other indirection agents) over the Internet. One of their main goals is to address triangle routing by optimizing routes between mobile nodes and correspondent nodes. Thus, a key component of such proposals is the algorithm to select proper mobility anchoring nodes for mobile nodes. However, most current solutions adopt a single‐anchoring approach, which means each mobile node attaches to a sole mobility anchor at one time. In this paper, “we argue that the single‐anchoring approach has drawbacks when facing various mobility scenarios. Then, we offer a novel multi‐anchoring approach that allows each mobile node to select an independent mobility anchor for each correspondent node. We show that in most cases our proposal gains more performance benefits with an acceptable additional cost by evaluation based on real network topologies. For the cases that lead to potential high cost, we also provide a lightweight version of our solution which aims to preserve most performance benefits while keeping a lower cost. At last, we demonstrate how our proposal can be integrated into current Mobile IP networks. Copyright © 2017 John Wiley & Sons, Ltd.
Wind speed generation for dynamic analysis
Authors: Fernandez‐Bernal F. , Alonso‐Alonso J.
Published: January 2017

A simple model to generate large band wind speed time sequences, especially easy to implement with a very reduced number of parameters, is presented. It is based on the calculation of a low‐frequency and a high‐frequency components. Low‐frequency component with 1 h sample time is obtained from a random process based on a conditional probability density function. Using real data from two different wind farms in two different months of the year, it has been found that Weibull distribution centered in the current hourly mean value seems to represent well the 1 h conditional PDF in all cases, and the standard deviation of this conditional Weibull is more or less in the range 1–1.3 m s−1 independently of the season of the year or the location. Regarding to high‐frequency component, low‐frequency samples are used as initial and final values and, between them, the turbulence component values are inserted. For that, it has been used a stochastic process based on a Beta probability function and a simple rescaling procedure with two non‐linear parameters, calculated in a recursive way. Unlike the usual modelling procedures presented in the literature, spectral power density functions are not used. This simplifies the implementation significantly. Ten second sample‐time real speed wind data from two different wind farms have been used to validate the proposed high‐frequency model, obtaining excellent results. A thorough revision of the main models found in the literature to produce wind speed time sequences for dynamic analysis is performed in the paper. Copyright © 2017 John Wiley & Sons, Ltd.
The current conceptualization of negative symptoms in schizophrenia
Authors: Marder Stephen R. , Galderisi Silvana
Published: January 2017

Negative symptoms have long been conceptualized as a core aspect of schizophrenia. They play a key role in the functional outcome of the disorder, and their management represents a significant unmet need. Improvements in definition, characterization, assessment instruments and experimental models are needed in order to foster research aimed at developing effective interventions. A consensus has recently been reached on the following aspects: a) five constructs should be considered as negative symptoms, i.e. blunted affect, alogia, anhedonia, asociality and avolition; b) for each construct, symptoms due to identifiable factors, such as medication effects, psychotic symptoms or depression, should be distinguished from those regarded as primary; c) the five constructs cluster in two factors, one including blunted affect and alogia and the other consisting of anhedonia, avolition and asociality. In this paper, for each construct, we report the current definition; highlight differences among the main assessment instruments; illustrate quantitative measures, if available, and their relationship with the evaluations based on rating scales; and describe correlates as well as experimental models. We conclude that: a) the assessment of the negative symptom dimension has recently improved, but even current expert consensus‐based instruments diverge on several aspects; b) the use of objective measures might contribute to overcome uncertainties about the reliability of rating scales, but these measures require further investigation and validation; c) the boundaries with other illness components, in particular neurocognition and social cognition, are not well defined; and d) without further reducing the heterogeneity within the negative symptom dimension, attempts to develop successful interventions are likely to lead to great efforts paid back by small rewards.
Antipsychotic augmentation vs. monotherapy in schizophrenia: systematic review, meta‐analysis and meta‐regression analysis
Authors: Galling Britta , Roldán Alexandra , Hagi Katsuhiko , Rietschel Liz , Walyzada Frozan , Zheng Wei , Cao Xiao‐Lan , Xiang Yu‐Tao , Zink Mathias , Kane John M. , Nielsen Jimmi , Leucht Stefan , Correll Christoph U.
Published: January 2017

Antipsychotic polypharmacy in schizophrenia is much debated, since it is common and costly with unclear evidence for its efficacy and safety. We conducted a systematic literature search and a random effects meta‐analysis of randomized trials comparing augmentation with a second antipsychotic vs. continued antipsychotic monotherapy in schizophrenia. Co‐primary outcomes were total symptom reduction and study‐defined response. Antipsychotic augmentation was superior to monotherapy regarding total symptom reduction (16 studies, N=694, standardized mean difference, SMD=–0.53, 95% CI: −0.87 to −0.19, p=0.002). However, superiority was only apparent in open‐label and low‐quality trials (both p<0.001), but not in double‐blind and high‐quality ones (p=0.120 and 0.226, respectively). Study‐defined response was similar between antipsychotic augmentation and monotherapy (14 studies, N=938, risk ratio = 1.19, 95% CI: 0.99 to 1.42, p=0.061), being clearly non‐significant in double‐blind and high‐quality studies (both p=0.990). Findings were replicated in clozapine and non‐clozapine augmentation studies. No differences emerged regarding all‐cause/specific‐cause discontinuation, global clinical impression, as well as positive, general and depressive symptoms. Negative symptoms improved more with augmentation treatment (18 studies, N=931, SMD=–0.38, 95% CI: −0.63 to −0.13, p<0.003), but only in studies augmenting with aripiprazole (8 studies, N=532, SMD=–0.41, 95% CI: −0.79 to −0.03, p=0.036). Few adverse effect differences emerged: D2 antagonist augmentation was associated with less insomnia (p=0.028), but more prolactin elevation (p=0.015), while aripiprazole augmentation was associated with reduced prolactin levels (p<0.001) and body weight (p=0.030). These data suggest that the common practice of antipsychotic augmentation in schizophrenia lacks double‐blind/high‐quality evidence for efficacy, except for negative symptom reduction with aripiprazole augmentation.
Das Tumorepigenom – von der Genregulation über die Tumorklassifikation zum Therapietarget
Authors: Ammerpohl Ole , Deckert Martina , Montesinos-Rongen Manuel
Published: January 2017

Epigenetische Regulationsmechanismen sind essenziell für den koordinierten Ablauf zahlreicher zellulärer Prozesse wie die Differenzierung und Entwicklung oder auch die Anpassung der Genaktivität an die herrschenden Umweltbedingungen. Insbesondere Tumorerkrankungen gehen mit oftmals umfangreichen Alterationen im Epigenom einher. Diese Veränderungen sind dabei vielfach charakteristisch entweder für die Tumorentität, das Stadium der Erkrankung oder aber das klinische Ansprechen des Tumors auf eine Therapie und damit die individuelle Prognose des Patienten. Nach einer kurzen Darstellung epigenetischer Marker und ihrer Bedeutung bei malignen Erkrankungen werden in diesem Artikel Alterationen im Tumorepigenom und ihre Nutzbarkeit im Rahmen einer individualisierten Medizin exemplarisch vorgestellt.
A quantitative theory for the continuity equation
Authors: Seis Christian
Published: January 2017

In this work, we provide stability estimates for the continuity equation with Sobolev vector fields. The results are inferred from contraction estimates for certain logarithmic Kantorovich–Rubinstein distances. As a by-product, we obtain a new proof of uniqueness in the DiPerna–Lions setting. The novelty in the proof lies in the fact that it is not based on the theory of renormalized solutions.
Experiences of Remote Mood and Activity Monitoring in Bipolar Disorder: A Qualitative Study
Authors: Saunders K.E.A. , Bilderbeck A.C. , Panchal P. , Atkinson L.Z. , Geddes J.R. , Goodwin G.M.
Published: January 2017

Background

Mobile technology enables high frequency mood monitoring and automated passive collection of data (e.g. actigraphy) from patients more efficiently and less intrusively than has previously been possible. Such techniques are increasingly being deployed in research and clinical settings however little is known about how such approaches are experienced by patients. Here, we explored the experiences of individuals with bipolar disorder engaging in a study involving mood and activity monitoring with a range of portable and wearable technologies.

Method

Patients were recruited from a wider sample of 50 individuals with Bipolar Disorder taking part in the Automated Monitoring of Symptom Severity (AMoSS) study in Oxford. A sub-set of 21 patients participated in a qualitative interview that followed a semi-structured approach.

Results

Monitoring was associated with benefits including increased illness insight, behavioural change. Concerns were raised about the potential preoccupation with, and paranoia about, monitoring. Patients emphasized the need for personalization, flexibility, and the importance of context, when monitoring mood.

Conclusions

Mobile and electronic health approaches have potential to lend new insights into mental health and transform healthcare. Capitalizing on the perceived utility of these approaches from the patients’ perspective, while addressing their concerns, will be essential for the promise of new technologies to be realised.
Epa Guidance on Emental Health Interventions in the Treatment of Posttraumatic Stress Disorder (Ptsd)
Authors: Gaebel W. , Großimlinghaus I. , Mucic D. , Maercker A. , Zielasek J. , Kerst A.
Published: January 2017

The aim of this EPA guidance was to develop recommendations on eMental health interventions in the treatment of posttraumatic stress disorder (PTSD). A systematic literature search was performed and 40 articles were retrieved and assessed with regard to study characteristics, applied technologies, therapeutic approaches, diagnostic ascertainment, efficacy, sustainability of clinical effects, practicability and acceptance, attrition rates, safety, clinician-supported vs. non-supported interventions and active vs. waiting-list controls. The reviewed studies showed a great heterogeneity concerning study type, study samples, interventions and outcome measures. Based on these findings, five graded recommendations dealing with symptom reduction, acceptability, type of administration, clinician support, self-efficacy and coping were developed.
Efficacy and safety of barbed suture in minimally invasive radical prostatectomy: A systematic review and meta‐analysis
Authors: Lin Yi‐Fei , Lai Si‐ke , Liu Qin‐Yu , Liao Bang‐Hua , Huang Jin , Du Liang , Wang Kun‐Jie , Li Hong
Published: January 2017

As one of the earliest surgeries applying knotless barbed suture, the minimally invasive radical prostatectomy (MIRP) was reported to have various effects on the patients and the surgeons. This study reviewed the available evidence about the efficacy and safety of barbed sutures in MIRP. We searched ClinicalTrials.gov, Cochrane Register of Clinical Studies, PubMed, and Embase to identify randomized controlled trials (RCTs) and cohort studies addressing the application of barbed sutures and conventional sutures in MIRP (until August 2016). Quality assessment was performed according to Cochrane recommendations. The data were analyzed using Review Manager (Version 5.3), and sensitivity analysis was performed by sequentially omitting each study. A total of 12 studies, including three RCTs (low to moderate risk of bias, 211 patients) and nine cohort studies (low to moderate risk of bias, 698 patients), fulfilled the study criteria. The pooling of trials did not show statistical difference. Pooling data of cohort studies showed that suture time [mean difference (MD) = −8.52, 95% confidence interval (CI) = −12.60 to −4.43, p < 0.0001] and length of hospital stay (MD = −0.96, 95% CI = −1.80 to −0.11, p = 0.03) were significantly shorter in the barbed group. Results of continence rate varied according to different studies. Subgroup analysis by type of MIRP suggested that patients who underwent barbed suture during robot‐assisted surgeries had a shorter hospital stay (MD = −1.13, 95% CI = −1.82 to −0.45, p = 0.001). During the laparoscopic surgery, patients in the barbed suture group had fewer postoperative complications [odds ratio = 0.29, 95% CI = 0.08–0.98, p = 0.05). However, more evidence is needed to validate this state‐of‐the‐art technology.
Speed and structure of turbulent fronts in pipe flow
Authors: Song Baofang , Barkley Dwight , Hof Björn , Avila Marc
Published: January 2017

Using extensive direct numerical simulations, the dynamics of laminar–turbulent fronts in pipe flow is investigated for Reynolds numbers between $Re=2000$ and 5500. We here investigate the physical distinction between the fronts of weak and strong slugs both by analysing the turbulent kinetic energy budget and by comparing the downstream front motion to the advection speed of bulk turbulent structures. Our study shows that weak downstream fronts travel slower than turbulent structures in the bulk and correspond to decaying turbulence at the front. At $Re\simeq 2900$ the downstream front speed becomes faster than the advection speed, marking the onset of strong fronts. In contrast to weak fronts, turbulent eddies are generated at strong fronts by feeding on the downstream laminar flow. Our study also suggests that temporal fluctuations of production and dissipation at the downstream laminar–turbulent front drive the dynamical switches between the two types of front observed up to $Re\simeq 3200$.
Asynchronous behavior of outlet glaciers feeding Godthåbsfjord (Nuup Kangerlua) and the triggering of Narsap Sermia's retreat in SW Greenland
Authors: MOTYKA ROMAN J. , CASSOTTO RYAN , TRUFFER MARTIN , KJELDSEN KRISTIAN K. , VAN AS DIRK , KORSGAARD NIELS J. , FAHNESTOCK MARK , HOWAT IAN , LANGEN PETER L. , MORTENSEN JOHN , LENNERT KUNUK , RYSGAARD SØREN
Published: January 2017

We assess ice loss and velocity changes between 1985 and 2014 of three tidewater and five-land terminating glaciers in Godthåbsfjord (Nuup Kangerlua), Greenland. Glacier thinning accounted for 43.8 ± 0.2 km3 of ice loss, equivalent to 0.10 mm eustatic sea-level rise. An additional 3.5 ± 0.3 km3 was lost to the calving retreats of Kangiata Nunaata Sermia (KNS) and Narsap Sermia (NS), two tidewater glaciers that exhibited asynchronous behavior over the study period. KNS has retreated 22 km from its Little Ice Age (LIA) maximum (1761 AD), of which 0.8 km since 1985. KNS has stabilized in shallow water, but seasonally advects a 2 km long floating tongue. In contrast, NS began retreating from its LIA moraine in 2004–06 (0.6 km), re-stabilized, then retreated 3.3 km during 2010–14 into an over-deepened basin. Velocities at KNS ranged 5–6 km a−1, while at NS they increased from 1.5 to 5.5 km a−1 between 2004 and 2014. We present comprehensive analyses of glacier thinning, runoff, surface mass balance, ocean conditions, submarine melting, bed topography, ice mélange and conclude that the 2010–14 NS retreat was triggered by a combination of factors but primarily by an increase in submarine melting.
Dietary responses of Sahul (Pleistocene Australia–New Guinea) megafauna to climate and environmental change
Authors: DeSantis Larisa R. G. , Field Judith H. , Wroe Stephen , Dodson John R.
Published: January 2017

Throughout the late Quaternary, the Sahul (Pleistocene Australia–New Guinea) vertebrate fauna was dominated by a diversity of large mammals, birds, and reptiles, commonly referred to as megafauna. Since ca. 450–400Ka, approximately 88 species disappeared in Sahul, including kangaroos exceeding 200kg in size, wombat-like animals the size of hippopotamuses, flightless birds, and giant monitor lizards that were likely venomous. Ongoing debates over the primary cause of these extinctions have typically favored climate change or human activities. Improving our understanding of the population biology of extinct megafauna as more refined paleoenvironmental data sets become available will assist in identifying their potential vulnerabilities. Here, we apply a multiproxy approach to analyze fossil teeth from deposits dated to the middle and late Pleistocene at Cuddie Springs in southeastern Australia, assessing relative aridity via oxygen isotopes as well as vegetation and megafaunal diets using both carbon isotopes and dental microwear texture analyses. We report that the Cuddie Springs middle Pleistocene fauna was largely dominated by browsers, including consumers of C4shrubs, but that by late Pleistocene times the C4dietary component was markedly reduced. Our results suggest dietary restriction in more arid conditions. These dietary shifts are consistent with other independently derived isotopic data from eggshells and wombat teeth that also suggest a reduction in C4vegetation after ~45 Ka in southeastern Australia, coincident with increasing aridification through the middle to late Pleistocene. Understanding the ecology of extinct species is important in clarifying the primary drivers of faunal extinction in Sahul. The results presented here highlight the potential impacts of aridification on marsupial megafauna. The trend to increasingly arid conditions through the middle to late Pleistocene (as identified in other paleoenvironmental records and now also observed, in part, in the Cuddie Springs sequence) may have stressed the most vulnerable animals, perhaps accelerating the decline of late Pleistocene megafauna in Australia.
D. A. Ọbasa (1879–1945): a Yoruba poet, culture activist and local intellectual in colonial Nigeria
Authors: Akinyẹmi Akintunde
Published: January 2017

This article examines the works of one of the earliest Yoruba poets, Denrele Adetimikan Ọbasa (1879–1945), a member of the local intelligentsia in colonial Nigeria. In my assessment of the poet as a culture activist and local intellectual, I draw on biographical information, extensive archival research and relevant textual illustration. The central argument of the article is that Ọbasa exploits Yoruba communal oral resources for ideas, themes and other linguistic influences in his poetry. Therefore, the essay explores the creative ability of Ọbasa to preserve different forms of oral literary material in his poetic composition and how he uses the folkloric materials as instruments for raising the social consciousness of his readers. At this level, the article argues, Ọbasa transforms oral traditions into metaphorical and symbolic language that best articulates his political or philosophical positions. Thus, orality is not static, but dynamic, flexible and adaptable to change. The main article offers translations of excerpts from Ọbasa's poetry, while the online supplementary material offers more complete samples of Ọbasa's poems.
‘Kakube has come to stay’: the making of a cultural festival in Northern Ghana, 1989–2015
Authors: Lentz Carola , Wiggins Trevor
Published: January 2017

In Ghana, cultural festivals, usually initiated and organized by the chiefs, provide public arenas where local and regional political elites voice demands vis-à-vis central government, and where national politicians canvass for support. Festivals offer commercial opportunities, forums to promote ‘development’, and occasions for entertainment. Yet advocating for ‘our own culture’ stands out as their very raison d’être, offering a frame for cultural entrepreneurs to organize performances that express and reconfigure local styles of music and dance to fit national formats. In this article, we examine such processes of cultural creation for the Kakube Festival in Nandom, a paramount chiefdom in north-western Ghana. We analyse the cultural building blocks and their evolution during the festival's history as well as the context of changing national politics of cultural heritage in which the festival developed. We discuss the invention of a cultural festival to create local alliances and stake claims at the regional and national political level, and how the desire to assert a presence in the national political and cultural arena has transformed the ways in which local culture is defined and presented. We examine the tensions at the heart of such an event, where traditions of chiefly patronage and allegiance meet the requirements of modern political and bureaucratic systems of funding, and the criteria of excellence in cultural performance. Music and dance are essential components and we analyse the evolution and adaptation of these elements alongside the critical path management of the event that has led to its local and national profile.