bluuebunny/crossref_metadata_2025 huggingface dataset:
Myeloid lineage switch following chimeric antigen receptor T‐cell therapy in a patient with TCF3‐ZNF384 fusion‐positive B‐lymphoblastic leukemia
Authors: Oberley Matthew J. , Gaynon Paul S. , Bhojwani Deepa , Pulsipher Michael A. , Gardner Rebecca A. , Hiemenz Matthew C. , Ji Jianling , Han Jennifer , O'Gorman Maurice R.G. , Wayne Alan S. , Raca Gordana
Published: May 2018

A pediatric patient diagnosed initially with B‐lymphoblastic leukemia (B‐ALL) relapsed with lineage switch to acute myeloid leukemia (AML) after chimeric antigen receptor T‐cell (CAR‐T) therapy and hematopoietic stem cell transplant. A TCF3‐ZNF384 fusion was identified at diagnosis, persisted through B‐ALL relapse, and was also present in the AML relapse cell population. ZNF384‐rearrangements define a molecular subtype of B‐ALL characterized by a pro‐B‐cell immunophenotype; furthermore, ZNF384‐rearrangements are prevalent in mixed‐phenotype acute leukemias. Lineage switch following CAR‐T therapy has been described in patients with KMT2A (mixed lineage leukemia) rearrangements, but not previously in any patient with ZNF384 fusion.
Theoretical model and simulation of carrier heating with effects of nonequilibrium hot phonons in semiconductor photovoltaic devices
Authors: Tsai Chin‐Yi
Published: May 2018

A theoretical model and its rate equations of carrier number and energy densities are proposed and presented for calculating carrier heating in semiconductor photovoltaic devices. The rate equation for carrier number density is the Shockley‐Queisser theoretical model, while the rate equation for carrier energy density includes the carrier interband energy relaxation via radiative recombination and the intraband energy relaxation via the interactions between carriers and polar longitudinal optical phonons. The carrier intraband energy relaxation is calculated by incorporating the effects of nonequilibrium hot phonons and the Thomas‐Fermi static screening. This model and its rate equations are employed for numerical simulations of the magnitude of carrier heating and its effects on the current‐voltage relations of bulk GaAs solar cells under different concentration ratios and with different widths of the active region. The simulation results demonstrate that carrier temperature in general heats up to 400 to 900 K at short‐circuit operating condition. This carrier heating cools down to lattice temperature when the device approaches its open‐circuit point. Based on these numerical results, effects of carrier heating on the performance of conventional solar cells and also their implications for the design of hot‐carrier solar cells will be discussed.
NeuroCog FX study: A multicenter cohort study on cognitive dysfunction in patients with early breast cancer
Authors: Rick Oliver , Reuß‐Borst Monika , Dauelsberg Timm , Hass Holger G. , König Volker , Caspari Reiner , Götz‐Keil Gabriele , Pfitzner Jürgen , Kerschgens Christa , Fliessbach Klaus , Hoppe Christian
Published: May 2018

Objective

Complaints about cognitive dysfunction (CD) reportedly persist in approximately one third of breast cancer patients, but the nature of CD and possible risk factors are unknown.

Methods

A cross‐sectional, multicenter study was set up at 9 German oncological rehabilitation centers. Objective cognitive performance was assessed by the NeuroCog FX test, a short computerized screening (duration <30 minutes) which assesses working memory, alertness, verbal/figural memory, and language/executive. Patients' test performance was correlated with treatment factors (chemo‐, radiotherapy), subjective performance (FEDA), depression (PHQ‐9), quality of life (EORTC QLQ‐30), and clinical characteristics.

Results

From February 2013 to December 2014, a clinically homogenous sample of 476 patients was recruited (early tumor stage [T0‐T2]: 93%; node‐negative: 67%; chemotherapy: 61%; radiotherapy: 84%). NeuroCog FX could be administered in 439 patients (92%; median age: 50 [24‐62] years). Patients showed decreased performance in attentional‐executive functions (but not verbal/figural memory) and a 3‐fold rate of CD in terms of below average performance in at least 1 cognitive domain (42%). Approximately 40% of the patients also reported subjective cognitive impairment (FEDA). No therapy‐specific effect on test performance was obtained in the NeuroCog FX test.

Conclusions

Breast cancer survivors showed objective attentional‐executive and subjective cognitive impairments. No therapy‐specific adverse side effect on objective cognitive performance was found. Depression strongly contributed to objective and subjective cognitive complaints and reduced quality of life.
Electrical, Mechanical, and Electromagnetic Shielding Properties of Silver Nanowire‐Based Transparent Conductive Films
Authors: Zhang Xuan , Zhong Yanli , Yan Yue
Published: May 2018

In this work, an acrylate‐based organic coating is developed to cover the electrically conductive silver nanowires (AgNWs) to improve the adhesion properties of AgNWs on PMMA substrates. A simple spray coating technique is performed to obtain large scale and highly uniform conductive silver nanowire films on PMMA substrates. The AgNWs covered by organic coatings are evaluated ex situ in terms of adhesion, transparency, electrical, mechanical, and electromagnetic shielding properties. Results indicated the adhesion of AgNWs covered by coatings is greatly superior to the uncovered AgNWs, which can be attributed to the strong hydrogen interfacial bond between the coating and PMMA substrate. Furthermore, the overall properties, including good transparency (≥80% in the visible range), flexibility (bending more than 1000 cycles), electromagnetic shielding (larger than 30 GHz from 1 to 18 GHz), meet the requirements of transparent parts in the aeronautical industry, and other commercial fields.
Structure‐Related Thermal Properties of Type‐VII Clathrates SrNi2P4 and BaNi2P4 at Low Temperature
Authors: Novikov Vladimir , Pilipenko Kirill , Matovnikov Aleksandr , Mitroshenkov Nikolay , Plokhikh Igor , Tyablikov Aleksandr , Shevelkov Andrey
Published: May 2018

Heat capacity CP(T) (2–300 K) and unit cell parameters a(T), b(T), and c(T) (5–300 K) of type‐VII clathrates SrNi2P4 and BaNi2P4 have been investigated experimentally. The studied compounds are prepared by a two‐stage ampoule synthesis. Diffuse maxima of CP(T) near 5 K along with anomalies in temperature dependencies of unit cell parameters below 10 K are observed and related to the influence of two‐level systems in guest‐atom substructures. Joint analysis of temperature dependencies of heat capacity and unit cell volume of both clathrates within the frames of the Debye–Einstein model allowed determining characteristic temperatures of the clathrate frameworks and guest atoms as well as parameters of the two‐level systems. The relationships of the obtained characteristics and the peculiarities of the crystal structures of SrNi2P4 and BaNi2P4 are discussed.
LaFeO3 thin films as relevant models for the surface investigation of 3‐way catalysts
Authors: Nandi Shreya , Blanck Dimitri , Carlier Thomas , Chambrier Marie‐Hélène , Mamede Anne‐Sophie , Trentesaux Martine , Simon Pardis , Nuns Nicolas , Roussel Pascal , Ferri Anthony , Paul Jean‐Francois , Berrier Elise
Published: May 2018

Lanthanum orthoferrite, a highly potential 3‐way catalyst, shaped as a polycrystalline thin film has been comprehensively analysed by combining bulk and surface characterization techniques. The possibility to accomplish unprecedented surface information has been presented, thanks to the combined use of LEIS, XPS, and ToF‐SIMS. The structural, morphological, and surface properties at nanometric scale make such thin films indistinguishable from powdered solids. Thus, the relevance of using such model materials for advanced surface investigations of LaFeO3±δ‐based 3‐way catalysts has been demonstrated.
The analysis of thermal and anodic oxide layers on selected biocompatible titanium alloys
Authors: Krčil Jan , Rafaj Zdeněk , Mára Vladimír , Krum Stanislav , Starý Vladimír , Nehasil Václav , Sobotová Jana
Published: May 2018

In the case of titanium alloys, the oxide layers on their surfaces strongly influence biocompatibility and corrosion resistance. To improve these characteristics, properties of oxide layers prepared by various methods on different base materials were examined. In this work, samples of widely used biomaterials, CP titanium grade 2 and alloy Ti6Al4V, were compared with recently developed β‐titanium alloy Ti‐39 wt% Nb. On the samples from these materials, the thermal (600°C/8 hr/atmospheric air) and anodic (1‐M H2SO4/100 V/1 hr) oxide layers were prepared. The change of surface color was observed. The surface topography of oxidized samples was observed using scanning electron microscopy. The thickness of oxide layers was measured and observed on the cross‐sectional samples. The further analysis of oxide layers surfaces was conducted using X‐ray photoelectron spectroscopy and atomic force microscopy. The growth of hydroxyapatite for further comparison of oxide layers was realized in Hank' balanced salt solution.
Multifunctional Logic Applications of a Single Molecule: A Molecular Photo‐Switch Performing as Simple and Complex Gates, Memory Element, and a Molecular Keypad Lock
Authors: Karar Monaj , Shit Pradip , Halder Basudeb , Mallick Arabinda , Majumdar Tapas
Published: May 2018

Carbazole (CZ) can act as a photo‐switch leading to a multifunctional logic system when triggered by fluoride (F–) ions, H2O and light, through efficient interaction of the pyrrole unit with the anions. Here we are reporting a unimolecular platform of CZ (and case specific CZ‐F–) that can be configured as NOT, YES, complimentary IMPLICATION and INHIBIT, a new complex logic gate performing IF‐THEN and NOT operations and a memory element with cyclic “Erase‐Read‐Write‐Read” ability with feedback loop mechanism. The fluorescence responses of the CZ system also have been exploited to design a potential highly secured molecular keypad lock operating with a purely opto‐chemical password composed with optical and chemical input keys. The system displays the applications of light responsive molecules as multifunctional, reconfigurable molecular logic devices that may lead towards true molecular information processing units.
A Ce(III)‐Based Coordination Polymer as Sorbent for the Removal of Pb2+ and Cd2+ Ions from Water
Authors: Abbasi Alireza , Amirshekari Shokoufeh , Najafi Mahnaz , Shahbaazi Hamidreza
Published: May 2018

A two‐dimensional coordination polymer based on Ce(III), [Ce2(μ3‐atp)2(μ2‐atp)(H2O)8].4H2O (1) (atp=2‐aminoterephthalate), was synthesized by solvent diffusion approach. The coordination polymer was characterized by X‐ray single crystal diffraction, powder X‐ray diffraction (PXRD), thermal analysis (TGA) and Fourier transformation infrared (FT‐IR) spectroscopy. Coordination polymer 1 was employed as sorbent for the removal of Cd2+ and Pb2+ from water under room conditions. Compound 1 displayed the same affinity for the adsorption of the metal ions and could be reused for the adsorption process after a simple treatment.
Excitons with Reverse Rectifying Characteristics for Superior Solar Photocatalysis
Authors: Samadi‐Maybodi Abdolraouf , Reza Shariati Mohammad
Published: May 2018

This study demonstrates an inverted energy‐gradient hybrid nanoparticle architecture that supports the formation of 2D excitons in the nanoshell domain. The developed geometry places a wide‐gap semiconductor quantum dot (ZnS, Eg= 3.68 eV) at the core of the nanocomposite particle in order to funnel the photoinduced energy into the low‐gap (CdS, Eg= 2.42 eV) shell layer. This inverted band regime helps to extract the photogenerated excitons into the shell and hence increases the exciton transport quantum efficiency, hereby leading to the superior photocatalytic efficiency for photoredox reactions over the nanohybrid. To demonstrate bandgap engineering and photoinduced charge carrier delocalization, we employed steady‐state and time‐resolved emission and absorption techniques in the presence and absence of an electron quencher (4‐nitrophenol) and hole quencher (4‐methoxyphenol). The significant suppression of band‐edge emissions and the decrement of the fluorescence lifetimes demonstrated the key role of nanoshell on the transfer of photogenerated charge carriers from core to the surface of the photocatalyst. Detailed investigations of the photocatalytic activity of ZnS@CdS and kinetic study of the reactions were also carried out under solar radiation. The contribution of O2•− and •OH to photocatalytic reactions revealed respectively via luminol chemiluminescence and terephthalic acid photoluminescence techniques.
Selective Cu2+ Ion Sensing by Nanoaggregates of Pyridyl‐2,6‐bis(3‐allylsalicylaldehyde)hydrazone
Authors: Rai Abhishek , Tripathi Kamini , Kumar Sonkar Avinash , James Tony D. , Yashaswee Saurabh , Kumar Trigun Surendra , Mishra Lallan
Published: May 2018

Pyridyl‐2,6‐bis(3‐allylsalicylaldehyde) hydrazone (PYAL) forms nanoaggregates (nPYAL) in THF:water (10:90,v/v) with enhanced emission. The nanoagregates display selective and reversible detection of Cu2+ ions with concomitant changes in their morphology and sizes. The detection of Cu2+ ions in human melanoma MDA MB 435 s cell lines using nPYAL has been demonstrated.
Luminescent Anticancer Acenaphtho[1, 2‐b]quinoxaline: Green Synthesis, DFT and Molecular Docking Studies, Live‐Cell Imaging and Reactivity towards Nucleic Acid and Protein BSA
Authors: De Sourav , Subran Sunisha Kottukulam , Ramasamy Selva kumar , Banerjee Subhasis , Paira Priyankar , Kalleshappa Ashok Kumar Somanahalli
Published: May 2018

A series of acenaphtho[1, 2‐b]quinoxaline derivatives 3 a‐3 j were prepared using single step condensation of acenaphthoquinone with different o‐phenylene diamine derivatives on water under sonication. Interaction of 9‐fluoro acenaptho[1, 2‐b]quinoxaline (3 g) with calf‐thymus DNA has been explored by using absorption and emission techniques. The compound 3 g cleave DNA oxidatively without any exogenous additives. The protein binding ability has been observed by quenching of tryptophan emission in the presence of 3 g using bovine serum albumin (BSA) as model protein. The DNA and protein docking study suggests that most of the quinoxaline derivatives interact with DNA through the minor groove and occupies the active site of the protein favorably by hydrogen bonding. The density functional calculations carried out on 3 a‐3 j have shown that electron‐rich regions in the highest occupied orbital are localized on the quinoxaline moiety. Live‐cells imaging result showed the clear evidence of strong cellular uptake of compound 3 g in HeLa cell line. The MTT assay concluded that compounds:9,10‐dichloroacenaptho[1, 2‐b]quinoxaline (3 d), 9‐bromoacenaptho[1, 2‐b]quinoxaline (3 e), 3 g and 9‐chloro‐10‐fluroacenaptho[1, 2‐b]quinoxaline (3 j) were exhibited highly selective cytotoxicity profiles in two cancer cell lines such as MCF‐7 and HeLa with respect to normal HEK‐293. Among them, compound 3 g displayed high potency and selectivity in all the cell lines.
Green Synthetic Approach for the Construction of 3,5‐Disubstituted 1,2,4‐Oxadiazoles and Ataluren Analogues from Dithioesters Using Water
Authors: Swarup Hassan A. , Chaithra Nagaraju , Mantelingu Kempegowda , Rangappa Kanchugarkoppal S.
Published: May 2018

An innovative green synthesis of 3,5‐disubstituted 1,2,4‐oxadiazoles from dithioesters using water as a solvent. This approach becomes more interesting because it undergoes nucleophilic substitution–dehydration–intramolecular cyclization in a single step to give 3,5‐disubstituted 1,2,4‐oxadiazoles in good to excellent yields under transition‐metal free conditions and allows wide functional group tolerance. This green protocol leads to synthesis of a drug lead molecule, Ataluren and their analogues.
Using Bispyrene Fluorescence Probe for Determining the Multiple States of Organogel
Authors: Liang Yong , Tang Jun , Wang Xiang , Zhao Siqi , Luo Ting , Shuai Cijun , Jiang Jinzhi , Cai Jianfeng , Xu Hai
Published: May 2018

A bispyrene fluorescence probe with the cavitand linkage (compound 1) was synthesized, which was proved to be a versatile platform due to the ability of adopting two spatially well‐defined conformations: a closed vase and an expanded kite. vase‐1 was switched to kite‐1 upon addition of TFA or cooling, whereas kite‐1 was isomerized to vase‐1 in the presence of NEt3 or through heating. The interconversion in this molecular switch was tightly associated with the change of fluorescence as we found that changing the temperature and pH of the system‐ a bispyrene compound 1 and gelator 2 led to the sol ‐ gel transformation and reversible intramolecular excimer emission. Briefly, the results show that the fluorescence decreases in the gelation phase and is enhanced in the solution due to variations in temperature and pH. we thus concluded that 1 could be a useful fluorescence probe to determine the multiple states of organogel.
Lattice‐Defect‐Induced Piezo Response in Methylammonium‐Lead‐Iodide Perovskite Based Nanogenerator
Authors: Dhar Joydeep , Sil Sayantan , Hoque Nur A. , Dey Arka , Das Sukhen , Ray Partha P. , Sanyal Dirtha
Published: May 2018

Methylammonium lead iodide (MAPbI3), a hybrid perovskite has become the semiconductor for case studies in several material properties due to its multi‐faceted electronic application. Other than photovoltaics, generation of piezoelectricity from hybrid perovskites has been reported previously, though its origin remained unsubstantiated. In this report, MAPbI3 with different degrees of crystal defects as determined by positron annihilation spectroscopy are developed through ball‐mill grinding procedure and utilized to fabricate flexible piezoelectric nanogenerators. We have demonstrated that at room temperature the lattice defects play the pivotal role in governing the ionic polarization which in principle governs the piezo‐effect in MAPbI3. The best device performance is exhibited by maximum defect containing sample having significant amount of Pb2+ defects. A device fabricated with 5 wt% PDMS composite produces piezo‐voltage of more than 100 V with a maximum power density of 0.3 mW/cm3 and can illuminate commercially available 30 blue light emitting diodes.
Comparative analysis of various models of Rogowski coil for very fast transient study
Authors: Hu Chen , Li Hong‐bin , Jiao Yang , Zhang Zhu , Li Kun
Published: May 2018

Switching operations of the disconnecting switch (DS) within high‐voltage gas‐insulated substations generate very fast transient electromagnetic interferences. Fast front pulses induced by these interferences produce high‐level transient currents that can lead to disturbed voltage output of Rogowski coil current transformers (RCTs). Predicting the transient characteristics of RCTs requires the implementation of accurate simulation models of the Rogowski coil. Concentrating on the DS operation process, this paper analyzes the performance of the lumped parameter model (LPM) and the distributed parameter model (DPM) available in the literature by means of comparisons in the time domain and frequency domain between two models, as well as comparisons between simulation results and measurement results in terms of the waveform properties and the distribution of amplitude. It is confirmed that the simulation results based on the DPM show better agreement with the measurements than those based on the LPM. It is also indicated that the maximum amplitude of the RCT output is approximately 580 mV with the dominant frequency of 2 MHz during the fast transient. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Combination vinblastine, prednisolone and toceranib phosphate for treatment of grade II and III mast cell tumours in dogs
Authors: Olsen Jaime A. , Thomson Maurine , O'Connell Kathleen , Wyatt Ken
Published: May 2018

This retrospective study evaluates the progression‐free interval and survival outcomes of 40 canine (Canis familiaris) patients with Patnaik grade II and III mast cell tumours treated with combination vinblastine, prednisolone and toceranib phosphate from 2011 to 2015. Patients were subdivided into three groups; patients who received neoadjuvant therapy for poorly operable lesions, patients who received adjuvant therapy following surgical resection and patients being palliated for gross metastatic disease. Median survival time (MST) for the neoadjuvant group was not reached. Median survival time for the remaining groups was 893 days and 218 days, respectively. This combination demonstrated response in 90% (26/29) patients with measurable disease. The predominant side effects related to this chemotherapy combination were gastrointestinal in origin. Further prospective studies are required to further validate the efficacy of this treatment protocol.
Vulnerability Multiplied: Health Needs Assessment of 13–18‐Year‐Old Female Orphan and Vulnerable Children in Kenya
Authors: Chhabra Rosy , Teitelman Nehama , Silver Ellen J. , Raufman Jill , Bauman Laurie J.
Published: May 2018

Globally, orphans and vulnerable children (OVCs) affected/infected by HIV/AIDS face many health risks, including malnutrition, early/unprotected sex, early forced marriage, HIV and other sexually transmitted infections (STIs), substance abuse, child labor, and high rates of mental health problems. We conducted formative research on mental health issues and HIV/STI risk behavior in Kasarani, a large slum in Nairobi, to guide the development of future interventions. Collaborating with a local community hospital, we used focus groups in the community to gather information that was used to generate a survey of 261 OVCs aged 13–18 years. Focus groups converged in deeming that OVCs were a high‐risk group, and girls were especially at higher health risk. Living within an impoverished environment makes these girls vulnerable to marginalization and exploitation. Specific concerns for girls included peer pressure, depression, suicidal ideation, sexual relationship with infected partners, lack of health education (specifically HIV/STI prevention information), and sexual exploitation by older men.
Three 2D Ln‐Sulfoterephthalate Complexes with 4,4′‐Bisbiphenyl‐imidazole Featuring Helical Chains
Authors: Ren Yi‐Xia , Wang Zhi‐Xiang , Zhang Mei‐Li , Guo Yan‐Hong , Wang Ji‐Jiang , Chen Xiao‐Li
Published: May 2018

A series of Ln‐sulfoterephthalate coordiantion polymers, namely, [Ln(2‐stp)(4,4′‐bbpi) (H2O)2]·H2O [Ln = Eu (1), Tb (2), Dy (3)] (2‐H3stp = 2‐sulfoterephthalate; 4,4′‐bbpi = 4,4′‐bisbiphenyl‐imidazole), were prepared by hydrothermal method and characterizatied by EA, IR, TGA, and PXRD technologies. Single crystal X‐ray diffraction analyses show that the three complexes are isostructral two‐dimensional network featuring helical chain structures. The fluorescence studies show that the emissions of the coordination polymers exhibit the characteristic peaks of lanthanide ions, which means they could be potential fluorescence materials.
How Was the Power of the Criminal Corpse Harnessed in Early Modern England?
Authors: Tarlow Sarah , Battell Lowman Emma
Published: May 2018

During the age of spectacular punishment, the bodies of those who threatened the State or social order were subject to highly visible symbolic justice. The executions and dead bodies of traitors in particular were put at the centre of acts of theatre. At the same time, new discourses around the dead body were taking shape at this time: especially discourses about anatomy and medicine; and a new theology that came to dominate British religion after the Reformation and altered profoundly the relationship between the living and the dead.
Hanging in Chains
Authors: Tarlow Sarah , Battell Lowman Emma
Published: May 2018

For a minority of convicted murderers the decision was taken to gibbet their body rather than send it for dissection. This chapter reviews what was involved practically in gibbeting a body (or ‘hanging in chains’ as it was known), including the locations chosen, and the technology of the gibbet. Three cases of hanging in chains are discussed: two in England and one in Canada. The Canadian one is especially interesting as it is a rare incidence of a woman being gibbeted (no women are known to have been gibbeted in Britain during this period). Finally, some enduring myths of the gibbet are described.
Seeking the Physical Remains of the Criminal Corpse
Authors: Tarlow Sarah , Battell Lowman Emma
Published: May 2018

In the first of two chapters considering the legacy of the criminal corpse we examine what happened to the physical remains of criminal bodies—partial and fragmented as they were by the end of their post-mortem punishments. Very few remains received any sort of burial, but a number were put to use as mounted skeletons or anatomical preparations for educational purposes. Other remains were curated as macabre souvenirs. Other uses included modelling for artists, experimental subjects for galvanism or phrenology; and the medicinal use of body parts in both orthodox and folk medicine.
Energy vs. QoX Network- and Cloud Services Management
Authors: Blanco Bego , Liberal Fidel , Lassila Pasi , Aalto Samuli , Sainz Javier , Gribaudo Marco , Pernici Barbara
Published: May 2018

Network Performance (NP)- and more recently Quality of Service/Experience/anything (QoS/QoE/QoX)-based network management techniques focus on the maximization of associated Key Performance Indicators (KPIs). Such mechanisms are usually constrained by certain thresholds of other system design parameters. e.g., typically, cost. When applied to the current competitive heterogeneous Cloud Services scenario, this approach may have become obsolete due to its static nature. In fact, energy awareness and the capability of modern technologies to deliver multimedia content at different possible combinations of quality (and prize) demand a complex optimization framework.

It is therefore necessary to define more flexible paradigms that make it possible to consider cost, energy and even other currently unforeseen design parameters not as simple constraints, but as tunable variables that play a role in the adaptation mechanisms.

In this chapter we will briefly introduce most commonly used frameworks for multi-criteria optimization and evaluate them in different Energy vs. QoX sample scenarios. Finally, the current status of related network management tools will be described, so as to identify possible application areas.
Traffic Management for Cloud Federation
Authors: Burakowski Wojciech , Beben Andrzej , van den Berg Hans , Bosman Joost W. , Hasslinger Gerhard , Kertesz Attila , Latre Steven , van der Mei Rob , Pflanzner Tamas , Poullie Patrick Gwydion , Sosnowski Maciej , Spinnewyn Bart , Stiller Burkhard
Published: May 2018

The chapter summarizes activities of COST IC1304 ACROSS European Project corresponding to traffic management for Cloud Federation (CF). In particular, we provide a survey of CF architectures and standardization activities. We present comprehensive multi-level model for traffic management in CF that consists of five levels: Level 5 - Strategies for building CF, Level 4 - Network for CF, Level 3 - Service specification and provision, Level 2 - Service composition and orchestration, and Level 1 - Task service in cloud resources. For each level we propose specific methods and algorithms. The effectiveness of these solutions were verified by simulation and analytical methods. Finally, we also describe specialized simulator for testing CF solution in IoT environment.
Efficient Simulation of IoT Cloud Use Cases
Authors: Markus Andras , Marques Andre , Kecskemeti Gabor , Kertesz Attila
Published: May 2018

In the paradigm of Internet of Things (IoT), sensors, actuators and smart devices are connected to the Internet. Application providers utilize the connectivity of these devices with novel approaches involving cloud computing. Some applications require in depth analysis of the interaction between IoT devices and clouds. Research in this area is facing questions like how we should govern such large cohort of devices, which may easily go up often to tens of thousands. In this chapter we investigate IoT Cloud use cases, and derive a general IoT use case. Distributed systems simulators could help in such analysis, but they are problematic to apply in this newly emerging domain, since most of them are either too detailed, or not extensible enough to support the to be modelled devices. Therefore we also show how generic IoT sensors could be modelled in a state of the art simulator using our generalized case to exemplify how the fundamental properties of IoT entities can be represented in the simulator. Finally, we validate the applicability of the introduced IoT extension with a fitness and a meteorological use case.
Scalable Traffic Quality and System Efficiency Indicators Towards Overall Telecommunication System’s QoE Management
Authors: Poryazov Stoyan , Saranova Emiliya , Ganchev Ivan
Published: May 2018

Conceptual and analytical models of an overall telecommunication system are utilized in this chapter for the definition of scalable indicators towards Quality of Service (QoS) monitoring, prediction, and management. The telecommunication system is considered on different levels – service phase, service stage, network, and overall system. The network itself is presented in seven service stages – A-user, A-terminal, Dialing, Switching, B-terminal Seizure, B-terminal, and B-user, each having its own characteristics and specifics. Traffic quality indicators are proposed on each level. Two network cost/quality ratios are proposed – mean and instantaneous – along with illustrative numerical predictions of the latter, which could be useful for dynamic pricing policy execution, depending on the network load. All defined indicators could be considered as sources for Quality of Experience (QoE) prediction.
The Value of Context-Awareness in Bandwidth-Challenging HTTP Adaptive Streaming Scenarios
Authors: Liotou Eirini , Hoßfeld Tobias , Moldovan Christian , Metzger Florian , Tsolkas Dimitris , Passas Nikos
Published: May 2018

Video streaming has become an indispensable technology in people’s lives, while its usage keeps constantly increasing. The variability, instability and unpredictability of network conditions pose one of the biggest challenges to video streaming. In this chapter, we analyze HTTP Adaptive Streaming, a technology that relieves these issues by adapting the video reproduction to the current network conditions. Particularly, we study how context awareness can be combined with the adaptive streaming logic to design a proactive client-based video streaming strategy. Our results show that such a context-aware strategy manages to successfully mitigate stallings in light of network connectivity problems, such as an outage. Moreover, we analyze the performance of this strategy by comparing it to the optimal case, as well as by considering situations where the awareness of the context lacks reliability.
Conceptual and Analytical Models for Predicting the Quality of Service of Overall Telecommunication Systems
Authors: Poryazov Stoyan , Saranova Emiliya , Ganchev Ivan
Published: May 2018

This chapter presents scalable conceptual and analytical performance models of overall telecommunication systems, allowing the prediction of multiple Quality of Service (QoS) indicators as functions of the user- and network behavior. Two structures of the conceptual presentation are considered and an analytical method for converting the presentations, along with corresponding additive and multiplicative metrics, is proposed. A corresponding analytical model is elaborated, which allows the prediction of flow-, time-, and traffic characteristics of terminals and users, as well as the overall network performance. In accordance with recommendations of the International Telecommunications Union’s Telecommunication Standardization Sector (ITU-T), analytical expressions are proposed for predicting four QoS indicators. Differentiated QoS indicators for each subservice, as well as analytical expressions for their prediction, are proposed. Overall pie characteristics and their causal aggregations are proposed as causal-oriented QoS indicators. The results demonstrate the ability of the model to facilitate a more precise dynamic QoS management as well as to serve as a source for predicting some Quality of Experience (QoE) indicators.
A minimal approach to the scattering of physical massless bosons
Authors: Boels Rutger H. , Luo Hui
Published: May 2018

Abstract

Tree and loop level scattering amplitudes which involve physical massless bosons are derived directly from physical constraints such as locality, symmetry and unitarity, bypassing path integral constructions. Amplitudes can be projected onto a minimal basis of kinematic factors through linear algebra, by employing four dimensional spinor helicity methods or at its most general using projection techniques. The linear algebra analysis is closely related to amplitude relations, especially the Bern-Carrasco-Johansson relations for gluon amplitudes and the Kawai-Lewellen-Tye relations between gluons and graviton amplitudes. Projection techniques are known to reduce the computation of loop amplitudes with spinning particles to scalar integrals. Unitarity, locality and integration-by-parts identities can then be used to fix complete tree and loop amplitudes efficiently. The loop amplitudes follow algorithmically from the trees. A number of proof-of-concept examples are presented. These include the planar four point two-loop amplitude in pure Yang-Mills theory as well as a range of one loop amplitudes with internal and external scalars, gluons and gravitons. Several interesting features of the results are highlighted, such as the vanishing of certain basis coefficients for gluon and graviton amplitudes. Effective field theories are naturally and efficiently included into the framework. Dimensional regularisation is employed throughout; different regularisation schemes are worked out explicitly. The presented methods appear most powerful in non-supersymmetric theories in cases with relatively few legs, but with potentially many loops. For instance, in the introduced approach iterated unitarity cuts of four point amplitudes for non-supersymmetric gauge and gravity theories can be computed by matrix multiplication, generalising the so-called rung-rule of maximally supersymmetric theories. The philosophy of the approach to kinematics also leads to a technique to control colour quantum numbers of scattering amplitudes with matter, especially efficient in the adjoint and fundamental representations.
An analytic superfield formalism for tree superamplitudes in D=10 and D=11
Authors: Bandos Igor
Published: May 2018

Abstract

Tree amplitudes of 10D supersymmetric Yang-Mills theory (SYM) and 11D supergravity (SUGRA) are collected in multi-particle counterparts of analytic on-shell superfields. These have essentially the same form as their chiral 4D counterparts describing

$$ \mathcal{N}=4 $$

N
=
4

SYM and

$$ \mathcal{N}=8 $$

N
=
8

SUGRA, but with components dependent on a different set of bosonic variables. These are the D=10 and D=11 spinor helicity variables, the set of which includes the spinor frame variable (Lorentz harmonics) and a scalar density, and generalized homogeneous coordinates of the coset

$$ \frac{\mathrm{SO}\left(D-2\right)}{\mathrm{SO}\left(D-4\right)\otimes \mathrm{U}(1)} $$

SO

D
−
2

SO

D
−
4

⊗
U

1

(internal harmonics).

We present an especially convenient parametrization of the spinor harmonics (Lorentz covariant gauge fixed with the use of an auxiliary gauge symmetry) and use this to find (a gauge fixed version of) the 3-point tree superamplitudes of 10D SYM and 11D SUGRA which generalize the 4 dimensional anti-MHV superamplitudes.
Supersymmetric solutions of the cosmological, gauged, ℂ magic model
Authors: Chimento Samuele , Ortín Tomás , Ruipérez Alejandro
Published: May 2018

Abstract

We construct supersymmetric solutions of theories of gauged

$$ \mathcal{N} $$

N

= 1, d = 5 supergravity coupled to vector multiplets with a U(1)R Abelian (Fayet-Iliopoulos) gauging and an independent SU(2) gauging associated to an SU(2) isometry group of the Real Special scalar manifold. These theories provide minimal supersymmetrizations of 5-dimensional SU(2) Einstein-Yang-Mills theories with negative cosmological constant. We consider a minimal model with these gauge groups and the “magic model” based on the Jordan algebra J
3
ℂ
with gauge group SU(3) × U(1)R, which is a consistent truncation of maximal SO(6)-gauged supergravity in d = 5 and whose solutions can be embedded in Type IIB Superstring Theory. We find several solutions containing selfdual SU(2) instantons, some of which asymptote to AdS5 and some of which are very small, supersymmetric, deformations of AdS5. We also show how some of those solutions can be embedded in Romans’ SU(2) × U(1)-gauged half-maximal supergravity, which was obtained by Lu, Pope and Tran by compactification of the Type IIB Superstring effective action. This provides another way of uplifting those solutions to 10 dimensions.
Exact correlators on the Wilson loop in $$ \mathcal{N}=4 $$ SYM: localization, defect CFT, and integrability
Authors: Giombi Simone , Komatsu Shota
Published: May 2018

Abstract

We compute a set of correlation functions of operator insertions on the 1/8 BPS Wilson loop in

$$ \mathcal{N}=4 $$

N
=
4

SYM by employing supersymmetric localization, OPE and the Gram-Schmidt orthogonalization. These correlators exhibit a simple determinant structure, are position-independent and form a topological subsector, but depend nontrivially on the ’t Hooft coupling and the rank of the gauge group. When applied to the 1/2 BPS circular (or straight) Wilson loop, our results provide an infinite family of exact defect CFT data, including the structure constants of protected defect primaries of arbitrary length inserted on the loop. At strong coupling, we show precise agreement with a direct calculation using perturbation theory around the AdS2 string worldsheet. We also explain the connection of our results to the “generalized Bremsstrahlung functions” previously computed from integrability techniques, reproducing the known results in the planar limit as well as obtaining their finite N generalization. Furthermore, we show that the correlators at large N can be recast as simple integrals of products of polynomials (known as Q-functions) that appear in the Quantum Spectral Curve approach. This suggests an interesting interplay between localization, defect CFT and integrability.
Lattice black branes: sphere packing in general relativity
Authors: Dias Óscar J. C. , Santos Jorge E. , Way Benson
Published: May 2018

Abstract

We perturbatively construct asymptotically$$ {\mathrm{\mathbb{R}}}^{1,3}\times {\mathbb{T}}^2 $$ℝ1,3×T2black branes with multiple inhomogeneous directions and show that some of them are thermodynamically preferred over uniform branes in both the microcanonical and canonical ensembles. This demonstrates that, unlike five-dimensional black strings, the instability of some unstable black branes has a plausible endpoint that does not require a violation of cosmic censorship.
Asymptotic symmetries of electromagnetism at spatial infinity
Authors: Henneaux Marc , Troessaert Cédric
Published: May 2018

Abstract

We analyse the asymptotic symmetries of Maxwell theory at spatial infinity through the Hamiltonian formalism. Precise, consistent boundary conditions are explicitly given and shown to be invariant under asymptotic angle-dependent u(1)-gauge transformations. These symmetries generically have non-vanishing charges. The algebra of the canonical generators of this infinite-dimensional symmetry with the Poincaré charges is computed. The treatment requires the addition of surface degrees of freedom at infinity and a modification of the standard symplectic form by surface terms. We extend the general formulation of well-defined generators and Hamiltonian vector fields to encompass such boundary modifications of the symplectic structure. Our study covers magnetic monopoles.
Quantum fields during black hole formation: how good an approximation is the Unruh state?
Authors: Juárez-Aubry Benito A. , Louko Jorma
Published: May 2018

Abstract

We study the quantum effects of a test Klein-Gordon field in a Vaidya space-time consisting of a collapsing null shell that forms a Schwazschild black hole, by explicitly obtaining, in a (1 + 1)-dimensional model, the Wightman function, the renormalised stress-energy tensor, and by analysing particle detector rates along stationary orbits in the exterior black hole region, and make a comparison with the folklore that the Unruh state is the state that emerges from black hole formation. In the causal future of the shell, we find a negative ingoing flux at the horizon that agrees precisely with the Unruh state calculation, and is the source of black hole radiation, while in the future null infinity we find that the radiation flux output in the Unruh state is an upper bound for the positive outgoing flux in the collapsing null shell spacetime. This indicates that back-reaction estimates based on Unruh state calculations over-estimate the energy output carried by so-called pre-Hawking radiation. The value of the output predicted by the Unruh state is however approached exponentially fast. Finally, we find that at late times, stationary observers in the exterior black hole region in the collapsing shell spacetime detect the local Hawking temperature, which is also well characterised by the Unruh state, coming from right-movers. Early-time discrepancies between the detector rates for the Unruh state and for the state in the collapsing shell spacetime are explored numerically.
Defunctioning Stomas Result in Significantly More Short‐Term Complications Following Low Anterior Resection for Rectal Cancer
Authors: Emmanuel Andrew , Chohda Ezzat , Lapa Christo , Miles Andrew , Haji Amyn , Ellul Joe
Published: May 2018

Background

Studies suggest that defunctioning stomas reduce the rate of anastomotic leakage and urgent reoperations after anterior resection. Although the magnitude of benefit appears to be limited, there has been a trend in recent years towards routinely creating defunctioning stomas. However, little is known about post‐operative complication rates in patients with and without a defunctioning stoma. We compared overall short‐term post‐operative complications after low anterior resection in patients managed with a defunctioning stoma to those managed without a stoma.

Methods

A retrospective cohort study of patients undergoing elective low anterior resection of the rectum for rectal cancer. The primary outcome was overall 90‐day post‐operative complications.

Results

Two hundred and three patients met the inclusion criteria for low anterior resection. One hundred and forty (69%) had a primary defunctioning stoma created. 45% received neoadjuvant radiotherapy. Patients with a defunctioning stoma had significantly more complications (57.1 vs 34.9%, p = 0.003), were more likely to suffer multiple complications (17.9 vs 3.2%, p < 0.004) and had longer hospital stays (13.0 vs 6.9 days, p = 0.005) than those without a stoma. 19% experienced a stoma‐related complication, 56% still had a stoma 1 year after their surgery, and 26% were left with a stoma at their last follow‐up. Anastomotic leak rates were similar but there was a significantly higher reoperation rate among patients managed without a defunctioning stoma.

Conclusion

Patients selected to have a defunctioning stoma had an absolute increase of 22% in overall post‐operative complications compared to those managed without a stoma. These findings support the more selective use of defunctioning stomas.

Study registration

Registered at www.researchregistry.com (UIN: researchregistry3412).
Pediatric Appendicitis Severity in KwaZulu‐Natal, South Africa: A Retrospective Cohort Analysis
Authors: Hernandez Matthew C. , Kong Victor Y. , Bruce John L. , Aho Johnathon M. , Laing Grant L. , Zielinski Martin D. , Clarke Damian L.
Published: May 2018

Background

Acute appendicitis is a common pediatric surgical emergency; however, there are few grading systems to assign disease severity. The American Association for the Surgery of Trauma (AAST) recently developed a grading system for a variety of emergency surgical conditions, including appendicitis. The severity of acute appendicitis in younger patients in KwaZulu‐Natal (South Africa) is unknown. We aimed to describe the disease severity in this patient population using the AAST grading system hypothesizing that the AAST grade would correlate with morbidity, management type, and duration of stay.

Materials

Single institutional review of patients <18 years old with a final diagnosis of acute appendicitis during 2010–2016 in KwaZulu‐Natal, South Africa, was performed. Demographics, physiologic and symptom data, procedural details, postoperative complications, and Clavien–Dindo classification were abstracted. AAST grades were generated based on intraoperative findings. Summary, univariate, and nominal logistic regression analyses were performed to compare AAST grade and outcomes.

Results

A total of 401 patients were identified with median [IQR] age of 11 [5–13], 65% male. Appendectomy was performed in all patients; 2.4% laparoscopic, 37.6% limited incision, and 60% midline laparotomy. Complications occurred in 41.6%, most commonly unplanned relaparotomy (22.4%), surgical site infection (8.9%), pneumonia (7.2%), and acute renal failure (2.9%). Complication rate and median length of stay increased with greater AAST grade (all p < 0.001). AAST grade was independently associated with increased risk of complications.

Conclusion

Pediatric appendicitis is a morbid disease in a developing middle‐income country. The AAST grading system is generalizable and accurately corresponds with management strategies as well as key clinical outcomes.

Level of evidence

Retrospective study, Level IV.

Study type

Retrospective single institutional study.
What Are the Indications for Prophylactic Embolization of Renal Angiomyolipomas? A Review of the Current Evidence in the Literature
Authors: Ryan James W. , Farrelly Cormac , Geoghegan Tony
Published: May 2018

Renal angiomyolipomas (AMLs) are benign tumours that may occur sporadically in the general population or in patients with tuberous sclerosis complex. The concern with AMLs is that of retroperitoneal hemorrhage, which can be fatal. Classically the trigger for prophylactic intervention was thought to be an AML diameter of ≥4 cm. However, this value is largely based on data from case series and heterogeneous retrospective studies. The PICO (patient, intervention, comparison, outcome) paradigm was used to systematically search the Cochrane database, TRIP database, and PubMed. The quality of evidence in the literature is poor regarding the indications for prophylactic embolization of AMLs (level 4). There are no prospective studies that adequately assess embolization vs other treatment modalities. However, using the available evidence we have produced recommendations for when intervention should be considered. We have also made recommendations regarding the direction of future research.