bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient encoding scheme for LT codes with soft iterative decoding
Authors: Zhang Meixiang , Kim Sooyoung
Published: May 2018

The Luby transform (LT) code is the first practical implementation of the digital fountain code, and its utilisation over a noisy channel invokes iterative decoding with soft information. For a good decoding performance, the role of the encoder degree distribution is vital. Especially, when utilising the soft iterative decoder, the bit error rate (BER) performance of the LT code can be improved by increasing the number of the degree‐1 encoding nodes and reducing the number of lower‐degree variable nodes. This study proposes an efficient LT‐code encoding algorithm that satisfies the conditions for improving the BER performance. The proposed scheme applies different priorities for selecting the neighbouring source nodes for given degrees of the encoding nodes. The simulation results demonstrate that the proposed scheme outperforms the existing schemes.
Sequence‐component‐based current differential protection for transmission lines connected with IIGs
Authors: Chen Shi , Tai Nengling , Fan Chunju , Liu Jian , Hong Shubin
Published: April 2018

Current differential protection is normally designed as the primary protection for the high‐voltage transmission lines. However, for the transmission line that is connected with the large‐scale inverter‐interfaced generators (IIGs), the performance of the conventional current differential protection is significantly affected by the difference between the sequence components of the fault currents on both sides of this line. This may result in the mal‐operation of protection relays. This study proposes a sequence‐component‐based current differential protection from a suitable fault model of IIGs under positive‐sequence control strategy. A differential coefficient is introduced to overcome the low sensitivity and poor reliability of the conventional differential protection. The proposed scheme discriminates the internal faults accurately from the external faults and the normal operating conditions. Additionally, the robustness analysis shows that this scheme is immune to different fault resistances, fault locations, and system parameters. Simulation results in power systems computer‐aided design/electro‐magnetic transient design and control validate the effectiveness of the proposed sequence‐component‐based protection scheme.
Distribution feeder‐level day‐ahead peak load forecasting methods and comparative study
Authors: Chen Tairen , Lehr Jane M. , Lavrova Olga , Martínez‐Ramón Manel
Published: April 2018

Day‐ahead peak load forecasting is a crucial factor for the electrical utility for daily power planning and distribution. A comparative study of the peak load forecasting at distribution feeder‐level circuits with high penetration level of PV generation are investigated. First, two years of private load data from the local utility and two years of public load data from Texas utility are analysed. The correlation analysis is applied to peak load and its driver factors. Next, Bayesian additive regression trees (BART) is employed to do peak load forecasting. Since the BART method takes an amount of time to generate the forecasting, the composite kernel methods based on Gaussian process regression (CKGPR) are designed. Then these methods are compared with multiple linear regression method and the support vector regression method based on the residential area and the business area load data. Thorough comparison results are presented based on five forecasting measurements. The BART has the best forecasting accuracy among all the indices, and the CKGPR also has counterpart forecasting results but with less computation time. Meanwhile, the forecasting accuracy difference between two areas is analysed. Lastly, influential driver factors are summarised.
Local measurement‐based technique for estimating fault location in multi‐source DC microgrids
Authors: Meghwani Anju , Srivastava Suresh C. , Chakrabarti Saikat
Published: April 2018

Quick fault detection and isolation of faulty section are desired in DC microgrid due to the presence of power electronic converters and low cable impedances. Owing to need of fast disconnection, limited time and data are available for online fault distance estimation. Some of the existing techniques consider source capacitors connected at only one end of the cable; therefore, assume that the fault current is contributed by only one end of the cable. This may not be true in the case of multi‐source DC microgrids, where fault current would be supplied from both the ends. Further, existing communication‐based techniques require either data synchronisation or fast communication network. To address these issues, this study proposes an online fault location method for multi‐source DC microgrid without using communication. The mathematical model of faulted cable section connected to sources at both the ends is derived. This model is used along with the measurements to determine the fault distance. The model consistency with the measurements is quantified using the confidence level based on the residual analysis. A ring‐type multi‐source DC microgrid system is considered and simulated on real‐time digital simulator to demonstrate the effectiveness of the proposed algorithm.
High availability cooperative free space optical communication link with various diversity combining methods
Authors: Dubey Vineeta , Chadha Devi , Chandra Vinod
Published: May 2018

The authors investigate the performance and reliability improvement of multiple relay cooperative free space optical (FSO) communication over direct link. Multiple gain combiner (MGC) method has been introduced as a diversity combining method which assures to provide a close to optimum performance as compared to maximal ratio combining (MRC). As compared to MRC, the proposed MGC technique does not require prior channel information and adaptive gain adjustment. Bit error rate (BER) performance improvement with different combining techniques, including MGC, in cooperative FSO system for different channel environments has been included in this study. BER performance for multiple relays for various combining techniques: selection combining, equal gain combining, MRC and MGC have been compared and it is seen that the performance of MGC is close to optimum MRC. High availability of the system is achieved by using multiple relays in the cooperative system. Markov model analysis for availability and mean time between failures of FSO systems in multiple relays cooperative communication has been done to verify the reliability improvement of a cooperative system with increasing number of relays.
One‐step combustion synthesis porous amorphous NiO/C/CNTs composite for high‐performance supercapacitors
Authors: Xuan Haicheng , Zhang Tuo , Xu Yuekui , Zhang Yongqing , Li Hui , Han Peide , Wang Dunhui , Du Youwei
Published: May 2018

High‐quality amorphous NiO/C/carbon nanotubes (CNTs) composite with an irregular porous structure have been successfully synthesised by a one‐step combustion process at 350°C for 2 h with a heating rate of 3°C/min in air. To fully understand the potential of NiO/C/CNTs, the phase composition, morphology and electrochemical properties of materials were investigated. Benefiting from the in situ formed carbon, the addition of the CNTs and the advantages of the porous structure, the materials have shown superior electrochemical properties for supercapacitors. The specific capacitance of the composite reaches up to 1618 F/g at a current density of 1 A/g. Furthermore, the NiO/C/CNTs||activate carbon asymmetric supercapacitor device demonstrates both a high energy density (25.9 Wh kg−1) and power density (5570 W kg−1), and delivers a better cycling stability (about 94%) after 7000 cycles, which is a potential material for further development of fabricating a supercapacitor electrode.
The VMC survey
Authors: Niederhofer F. , Cioni M.-R. L. , Rubele S. , Schmidt T. , Bekki K. , de Grijs R. , Emerson J. , Ivanov V. D. , Marconi M. , Oliveira J. M. , Petr-Gotzens M. G. , Ripepi V. , van Loon J. Th. , Zaggia S.
Published: May 2018

We present the first spatially resolved map of stellar proper motions within the central (~3.1 × 2.4 kpc) regions of the Small Magellanic Cloud (SMC). The data used for this study encompasses four tiles from the ongoing near-infrared VISTA survey of the Magellanic Clouds system and covers a total contiguous area on the sky of ~6.81 deg2. Proper motions have been calculated independently in two dimensions from the spatial offsets in the Ks filter over time baselines between 22 and 27 months. The reflex motions of approximately 33 000 background galaxies are used to calibrate the stellar motions to an absolute scale. The resulting catalog is composed of more than 690 000 stars which have been selected based on their position in the (J − Ks, Ks) color-magnitude diagram. For the median absolute proper motion of the SMC, we find (μαcos(δ), μδ) = (1.087 ± 0.192 (sys.) ± 0.003 (stat.), −1.187 ± 0.008 (sys.) ± 0.003 (stat.)) mas yr−1, consistent with previous studies. Mapping the proper motions as a function of position within the SMC reveals a nonuniform velocity pattern indicative of a tidal feature behind the main body of the SMC and a flow of stars in the south-east moving predominantly along the line-of-sight.
Numerical investigation of the optimum wind turbine sitting for domestic flat roofs
Authors: Ishfaq Salman Muhammad , Chaudhry Hassam Nasarullah
Published: May 2018

The power capacity of roof mounted wind turbines is dependent on several factors which influence its energy yield. In this paper, an investigation has been carried out using Computational Fluid Dynamics (CFD) to determine flow distribution and establish an optimum mounting location for a small wind turbine on a domestic flat roof. The realisable k-ε and SST k-ω turbulence models were compared to establish their consistency with one another with respect to the physical domain. Nine mounting locations were considered for a pole mounted wind turbine. Three windward positions on the upwind side of the flat surfaced building were considered as viable locations for mounting the small wind turbine. Out of the three windward locations, the central upwind (1,0) mounting position was seen to be producing the highest velocity of 5.3 m/s from the available ambient velocity which was 4 m/s. Therefore, this mounting location provided the highest extractable power for the wind turbine. Conclusively, wind properties along with the mounting locations can play a significant role in either enhancing or diminishing the small wind turbine's performance on a domestic flat roof.
Reanimation unter besonderen Umständen: Kreislaufstillstand bei implantiertem Linksherzassist-Device (LVAD)
Authors: Thiele Jochen , Matusch Dennis , Reifferscheid Florian
Published: May 2018

Nach einer körperlichen Auseinandersetzung in einem Bus des ÖPNV bricht eine Person reanimationspflichtig zusammen. Der eintreffenden RTW-Besatzung fällt eine Umhängetasche des Patienten auf, die einen lauten Pfeifton abgibt. Die körperliche Untersuchung und Inspektion der Umhängetasche durch den Notarzt ergibt als Ursache für den Pfeifton eine diskonnektierte Driveline eines Linksherzunterstützungssystems („left ventricular assist device“ = LVAD). Die Driveline wird wieder mit dem Kontroller in der Umhängetasche konnektiert. Die folgende Analyse des Herzrhythmus zeigt keine eindeutige elektrische Herzaktion, ein noninvasiver Blutdruck ist nicht messbar, der Patient bleibt bewusstlos. Das endtidale CO2 lag unter volumenkontrollierter Beatmung bei 35 mmHg. Aufgrund dieses Wertes wird zu diesem Zeitpunkt der ROSC definiert. Nach einer 24-stündigen Kühlung kann der Patient problemlos extubiert werden. Eine kardiochirurgische Intervention ist nicht notwendig. Aufgrund steigender Zahlen implantierter kardialer Assistsysteme ist mit einer Zunahme von Patienten im Rettungsdienst zu rechnen. Neben den Standardmaßnahmen der Reanimation kommt dem Beheben der Ursache des Kreislaufstillstandes höchste Priorität zu. Das Erheben von Vitalparametern ist aufgrund der fehlenden Pulsatilität eingeschränkt bis unmöglich. Die Messung des endtidalen CO2 kann hier zur Beurteilung der Kreislaufsituation genutzt werden.
Implementing, Connecting, and Evaluating a Standard-Based Integrated Operating Room within a German University Hospital
Authors: Dees Raluca , Merzweiler Angela , Schneider Gerd , Kasparick Martin , Mündermann Lars , Ahlbrandt Janko , Wagner Martin , Kenngott Hannes , Müller-Stich Beat , Bergh Björn
Published: May 2018

Background Digital operating rooms (ORs), when optimally designed and integrated, can reduce the complexity of the surgery suite. However, many integrated ORs are effectively isolated from other IT systems in the hospital because there is little or no connectivity with them. Within the German flagship project OR.NET, concepts and components were developed for a standard-based connection of the OR with hospital IT systems.

Objectives The aim of this work was to implement and evaluate OR.NET concepts and components within the existing IT landscape of a German university hospital. This article describes and evaluates the implemented architecture and processes for connecting a demo OR to existing hospital IT systems at Heidelberg University Hospital.

Methods For the design, establishment, and evaluation of standard-based connections of the demo OR with hospital IT systems, the iterative method “Design and Creation” with four iterations was applied.

Results A generic and a concrete architecture for several standard-based connection concepts of the demo OR were developed. Furthermore, the concrete architecture was implemented and evaluated for its technical and clinical relevance. The main benefits of the project were the establishment of basic requisites for improving the efficiency within the OR, easier operation of medical devices as a result of harmonized human–machine interfaces, and providing additional data for improving healthcare.

Conclusion OR.NET concepts for a standard-based connection of the OR with hospital IT systems have proven to be promising. They can serve as a reference for further integration scenarios in other hospitals.
Impact of Matrix-Assisted Laser Desorption/Ionization Time-of-Flight for the Identification of Gram-Positive Bloodstream Pathogens without Antimicrobial Stewardship Intervention in Hospitalized Children
Authors: Herrera Lisa , Culbreath Karissa , Dehority Walter
Published: May 2018

We performed a 2-year retrospective cohort study of inpatient children with growth of gram-positive bacteria from blood cultures identified with and without the use of matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) in the absence of an antimicrobial stewardship program. Use of MALDI-TOF reduced the time to organism identification by 15.7 hours (p < 0.0001). However, no differences in length of stay, time to optimization of antimicrobial therapy, or time to discontinuation of antibiotics for growth of contaminants were documented, suggesting that such potential patient-oriented benefits of MALDI-TOF may only be evident in the presence of a concurrent antimicrobial stewardship program.
Overcoming Tortuous Anatomy in Intracranial Intervention
Authors: Cherian Mathew , Mehta Pankaj , Santhosh Poyyamoli , Rahul Kareparambil , Jenny Gandhi , Elango Swamiappan
Published: May 2018

Intracranial interventions comprise a set of procedures, which are complex and challenging. Further, they are extremely risky because complications in the brain are usually associated with significant mortality and morbidity. Thus, a clear understanding is necessary to handle tortuous vessels because improper planning can result in a higher rate of complications. The combination of long sheaths, specialty wires, and preshaped catheters can enable us to access some of the most complex vascular anatomy. There are several conditions that can contribute to a difficult access. There are few techniques described by different authors. The authors have listed the techniques found useful based on their experience. These challenges include tortuous iliac arteries, dilated tortuous aortic arch, acute takeoff of the arch vessels, tortuous neck vessels with prominent loops, crossing a large aneurysm, extensive peripheral vascular disease, etc.
Der Instabilitätsindex als Instrument einer antizipatorischen Diagnostik und Therapie
Authors: Krautstrunk Gerhard , Dimitri Simone , Petzold Carolin Wessels Ernst Richard , Schmid-Schönbein Holger
Published: May 2018

Der Instabilitätsindex ist ein einfaches und auf psychonomischen Konzepten gestütztes Instrument, um kritische Fluktuationen und Instabilität beim individuellen Patienten zu erfassen, was zentral wichtig für die Erfassung der psychodynamischen Instabilität und deren erfolgreicher Behandlung ist.
A reaction cell for ambient pressure soft x-ray absorption spectroscopy
Authors: Castán-Guerrero C. , Krizmancic D. , Bonanni V. , Edla R. , Deluisa A. , Salvador F. , Rossi G. , Panaccione G. , Torelli P.
Published: May 2018

We present a new experimental setup for performing X-ray Absorption Spectroscopy (XAS) in the soft X-ray range at ambient pressure. The ambient pressure XAS setup is fully compatible with the ultra high vacuum environment of a synchrotron radiation spectroscopy beamline end station by means of ultrathin Si3N4 membranes acting as windows for the X-ray beam and seal of the atmospheric sample environment. The XAS detection is performed in total electron yield (TEY) mode by probing the drain current from the sample with a picoammeter. The high signal/noise ratio achievable in the TEY mode, combined with a continuous scanning of the X-ray energies, makes it possible recording XAS spectra in a few seconds. The first results show the performance of this setup to record fast XAS spectra from sample surfaces exposed at atmospheric pressure, even in the case of highly insulating samples. The use of a permanent magnet inside the reaction cell enables the measurement of X-ray magnetic circular dichroism at ambient pressure.
Dynamic strength properties and alpha-phase shock Hugoniot of iron and steel
Authors: Thomas S. A. , Hawkins M. C. , Matthes M. K. , Gray G. T. , Hixson R. S.
Published: May 2018

The properties of iron and steel are of considerable interest scientifically to the dynamic materials properties' community, as well as to a broader audience, for many applications. This is true in part because of the existence of a solid-solid phase (α–ε) transition at relatively modest stress (13 GPa). Because of this, there is a significant amount of data on iron and steel alloy shock compression properties at stresses above 13 GPa, but much less fundamental data under stress conditions lower than that, where the metals are in the α-phase. New data have been obtained under relatively low stress (below 10 GPa) conditions in which samples are subjected to low-velocity symmetric impact on the order of 0.2 to 0.4 km/s. We used well-developed flyer plate impact methods combined with velocity interferometry to measure wave speeds and strength properties in compression and tension. The shock α-phase Hugoniot data reported here are compared with literature values. A comparison of spall strength and Hugoniot elastic limit is made between different types of steel studied and for pure iron.
Controlling surface carrier density by illumination in the transparent conductor La-doped BaSnO3
Authors: Lochocki Edward B. , Paik Hanjong , Uchida Masaki , Schlom Darrell G. , Shen Kyle M.
Published: May 2018

LaxBa1-xSnO3 is a promising transparent conducting oxide whose high mobility facilitates potential applications in transparent electronics, oxide electronics, and power electronics. Here, we report quantitative comparisons between angle-resolved photoemission and density functional theory, demonstrating a close agreement between calculations and the measured bulk electronic structure. Further measurements reveal upward band bending at the film-vacuum interface, while ultraviolet (UV) exposure is found to increase the surface electron density, similar to other oxides. These results elucidate the LaxBa1-xSnO3 (LBSO) interfacial electronic structure and offer a route for UV carrier density control, critical steps towards realizing LBSO-based electronic devices.
Scale interaction and arrangement in a turbulent boundary layer perturbed by a wall-mounted cylindrical element
Authors: Tang Zhanqi , Jiang Nan
Published: May 2018

This study reports the modifications of scale interaction and arrangement in a turbulent boundary layer perturbed by a wall-mounted circular cylinder. Hot-wire measurements were executed at multiple streamwise and wall-normal wise locations downstream of the cylindrical element. The streamwise fluctuating signals were decomposed into large-, small-, and dissipative-scale signatures by corresponding cutoff filters. The scale interaction under the cylindrical perturbation was elaborated by comparing the small- and dissipative-scale amplitude/frequency modulation effects downstream of the cylinder element with the results observed in the unperturbed case. It was obtained that the large-scale fluctuations perform a stronger amplitude modulation on both the small and dissipative scales in the near-wall region. At the wall-normal positions of the cylinder height, the small-scale amplitude modulation coefficients are redistributed by the cylinder wake. The similar observation was noted in small-scale frequency modulation; however, the dissipative-scale frequency modulation seems to be independent of the cylindrical perturbation. The phase-relationship observation indicated that the cylindrical perturbation shortens the time shifts between both the small- and dissipative-scale variations (amplitude and frequency) and large-scale fluctuations. Then, the integral time scale dependence of the phase-relationship between the small/dissipative scales and large scales was also discussed. Furthermore, the discrepancy of small- and dissipative-scale time shifts relative to the large-scale motions was examined, which indicates that the small-scale amplitude/frequency leads the dissipative scales.
Effects of surface motion and electron-hole pair excitations in CO2 dissociation and scattering on Ni(100)
Authors: Luo Xuan , Zhou Xueyao , Jiang Bin
Published: May 2018

The energy transfer between different channels is an important aspect in chemical reactions at surfaces. We investigate here in detail the energy transfer dynamics in a prototypical system, i.e., reactive and nonreactive scattering of CO2 on Ni(100), which is related to heterogeneous catalytic processes with Ni-based catalysts for CO2 reduction. On the basis of our earlier nine-dimensional potential energy surface for CO2/Ni(100), dynamical calculations have been done using the generalized Langevin oscillator (GLO) model combined with local density friction approximation (LDFA), in which the former accounts for the surface motion and the latter accounts for the low-energy electron-hole pair (EHP) excitation. In spite of its simplicity, it is found that the GLO model yields quite satisfactory results, including the significant energy loss and product energy disposal, trapping, and steering dynamics, all of which agree well with the ab initio molecular dynamics ones where many surface atoms are explicitly involved with high computational cost. However, the GLO model fails to describe the reactivity enhancement due to the lattice motion because it intrinsically does not incorporate the variance of barrier height on the surface atom displacement. On the other hand, in LDFA, the energy transferred to EHPs is found to play a minor role and barely alter the dynamics, except for slightly reducing the dissociation probabilities. In addition, vibrational state-selected dissociative sticking probabilities are calculated and previously observed strong mode specificity is confirmed. Our work suggests that further improvement of the GLO model is needed to consider the lattice-induced barrier lowering.
Planar Nernst effect and Mott relation in (In,Fe)Sb ferromagnetic semiconductor
Authors: Bui Cong Tinh , Garcia Christina A. C. , Tu Nguyen Thanh , Tanaka Masaaki , Hai Pham Nam
Published: May 2018

Transverse magneto-thermoelectric effects were studied in an (In,Fe)Sb ferromagnetic semiconductor thin film under an in-plane magnetic field. We find that the thermal voltage is governed by the planar Nernst effect. We show that the magnetic field intensity dependence, magnetic field direction dependence, and temperature dependence of the transverse Seebeck coefficient can be explained by assuming a Mott relation between the in-plane magneto-transport and magneto-thermoelectric phenomena in (In,Fe)Sb.
Glasses of three alkyl phosphates show a range of kinetic stabilities when prepared by physical vapor deposition
Authors: Beasley M. S. , Tylinski M. , Chua Y. Z. , Schick C. , Ediger M. D.
Published: May 2018

In situ AC nanocalorimetry was used to characterize vapor-deposited glasses of three phosphates with increasing lengths of alkyl side chains: trimethyl phosphate, triethyl phosphate, and tributyl phosphate. The as-deposited glasses were assessed in terms of their reversing heat capacity, onset temperature, and isothermal transformation time. Glasses with a range of kinetic stabilities were prepared, including kinetically stable glasses, as indicated by high onset temperatures and long transformation times. Trimethyl phosphate forms kinetically stable glasses, similar to many other organic molecules, while triethyl phosphate and tributyl phosphate do not. Triethyl phosphate and tributyl phosphate present the first examples of non-hydrogen bonding systems that are unable to form stable glasses via vapor deposition at 0.2 nm/s. Based on experiments utilizing different deposition rates, we conclude that triethyl phosphate and tributyl phosphate lack the surface mobility required for stable glass formation. This may be related to their high enthalpies of vaporization and the internal structure of the liquid state.
Design and cold test of period-tapered double-ridge-loaded folded waveguide slow wave structure for Ka band TWTs
Authors: Lu Zhigang , Su Zhicheng , Wei Yanyu
Published: May 2018

A double-ridge-loaded folded waveguide (DRL-FW) travelling wave tube (TWT) based on period-tapered structure is proposed. Through analysing the dispersion characteristics of the DRL-FW slow wave structure (SWS), the physical mechanism of the band-edge oscillation is obtained. Period-tapered SWS is proposed and analysed for verifying the feasibility in suppressing upper-band-edge oscillation and increasing the output power. Then the electromagnetic characteristics and the beam-wave interaction of TWT based on the period-tapered DRL-FW SWS are investigated. The calculation results predict that it potentially could provide continuous wave power over 600W from 29 GHz to 32 GHz without upper-band-edge oscillation. The bandwidth expands from 29-31GHz to 29-32GHz and electron efficiency is increased from more than 8.3% to more than 11%, while the range of operating voltage expands from 22kV-22.5kV to 22kV-24kV. The corresponding saturated gain can reach over 36.8 dB. In addition, we have carried out experimental tests on the transmission characteristics of period-tapered DRL-FW SWS. The cold test results show that the voltage stand-wave ratio (VSWR) is below 1.8 in the range of 29-32GHz. Good transmission characteristics greatly reduce the risk of reflection wave oscillation, thus improving the stability of DRL-FW TWT.
ELIPatch, a thumbnail-size patch with immunospot array for multiplexed protein detection from human skin surface
Authors: Oh Dong Yoon , Na Hunjong , Song Seo Woo , Kim Jinhyun , In Hyunsoo , Lee Amos Chungwon , Jeong Yunjin , Lee Daewon , Jang Jisung , Kwon Sunghoon
Published: May 2018

Proteins secreted by skin have great potential as biomarkers for interpreting skin conditions. However, inconvenience in handling and bulky size of existing methods are existing limitations. Here, we describe a thumb-nail sized patch with the array of microdisks which captures multiple proteins from the skin surface. Microdisks with antibody on the surface enable multiplexed immunoassay. By self-assembly, microdisks are placed into 2-dimensional arrays on adhesive tape. The proposed Enzyme-Linked Immunospot array on a Patch shows sufficient sensitivity for IL-1α, IL1RA, IL-17A, IFN-g, and TNF-α, while IL-6 and IL-1β are non-detectable in some cases. As demonstrations, we quantified cytokines from different skin regions and volunteers in a high-spatial-resolution.
Doppler ultrasound can be used to monitor umbilical arterial blood flow in lightly sedated pigs at multiple gestational ages
Authors: Stenhouse Claire , Tennant Peter , Duncan W. Colin , Ashworth Cheryl J.
Published: May 2018

Doppler ultrasound was performed under moderate sedation (ketamine and azaperone) for 30 min to monitor umbilical arterial (UA) blood flow in one uterine horn of Large White × Landrace gilts (n = 23) at Gestational Days (GD) 30, 45, 60 and 90. Gilts were scanned before they were killed to examine relationships between litter size, sex ratio and five UA parameters (peak systolic velocity (PSV), end diastolic velocity (EDV), A/B (PSV to EDV) ratio, fetal heart rate (FHR) and resistance index (RI)). In gilts in which scans were obtained from all fetuses in the scanned horn, relationships between UA parameters, and fetal weight and sex were examined. A subset of gilts were sedated, scanned and recovered (SSR) earlier in gestation (GD30 or GD45) to assess the effects of sedation on later fetal development by comparison with control litters (no previous sedation). Temporal changes were observed in all UA parameters (P ≤ 0.001). At GD60 and GD90, FHR decreased with increasing duration of sedation (P ≤ 0.001). Sex ratio and fetal weight affected UA blood flow, whereas litter size and fetal sex did not. SSR at GD30 and GD45 was associated with decreased fetal weight at GD60 (P ≤ 0.001) and GD90 (P = 0.06) respectively, compared with controls. These results suggest maternal sedation during gestation affects fetal development, which should be investigated further. Measuring UA blood flow in growth-restricted porcine fetuses throughout gestation may be feasible.
The platypus nest: burrow structure and nesting behaviour in captivity
Authors: Thomas J. , Handasyde K. , Parrott M. L. , Temple-Smith P.
Published: May 2018

The platypus nesting burrow, where females lay eggs and rear their young, has not been well studied. We have little knowledge of its structure and the process of construction. This study aimed to investigate nesting behaviour of breeding females and to describe the structure and features of the burrow. We used infrared cameras to record behaviour of captive breeding female platypuses during the nest-building period, over nine years. After the young had become independent, we excavated 11 nesting burrows and mapped their structural features. Nesting behaviour was observed 7–15 days after mating and was an indicator of gravidity. Females invested an average of 8 h 18 min over 3.5 nights, gathering and transporting wet nesting material to their burrows. The nests were composed mostly of native mat-rush leaves. Nesting burrows varied in length from 3.2 to 10.4 m. They contained narrow tunnels, ‘pugs’ of backfilled earth, dead ends, multiple entrances and a chamber at the end that contained the nest. Appropriate nesting sites and nesting materials must be provided to female platypuses for captive breeding programs to succeed.
Multicompartment cell-based modeling of confined migration: regulation by cell intrinsic and extrinsic factors
Authors: Kumar Sandeep , Das Alakesh , Sen Shamik
Published: May 2018

Though cell and nuclear deformability are expected to influence efficiency of confined migration, their individual and collective influence on migration efficiency remains incompletely understood. In addition to cell intrinsic properties, the relevance of cell extrinsic factors on confined migration, if any, has not been adequately explored. Here we address these questions using a statistical mechanics-based stochastic modeling approach where cell/nuclear dimensions and their deformability are explicitly taken into consideration. In addition to demonstrating the importance of cell softness in sustaining confined migration, our results suggest that dynamic tuning of cell and nuclear properties at different stages of migration is essential for maximizing migration efficiency. Our simulations also implicate confinement shape and confinement history as two important cell extrinsic regulators of cell invasiveness. Together, our findings illustrate the strength of a multicompartment model in dissecting the contributions of multiple factors that collectively influence confined cell migration.
Metaphase kinetochore movements are regulated by kinesin-8 motors and microtubule dynamic instability
Authors: Klemm Anna H. , Bosilj Agneza , Gluncˇic´ Matko , Pavin Nenad , Tolic´ Iva M.
Published: May 2018

During metaphase, sister chromatids are connected to microtubules extending from the opposite spindle poles via kinetochores to protein complexes on the chromosome. Kinetochores congress to the equatorial plane of the spindle and oscillate around it, with kinesin-8 motors restricting these movements. Yet, the physical mechanism underlying kinetochore movements is unclear. We show that kinetochore movements in the fission yeast Schizosaccharomyces pombe are regulated by kinesin-8-promoted microtubule catastrophe, force-induced rescue, and microtubule dynamic instability. A candidate screen showed that among the selected motors only kinesin-8 motors Klp5/Klp6 are required for kinetochore centering. Kinesin-8 accumulates at the end of microtubules, where it promotes catastrophe. Laser ablation of the spindle resulted in kinetochore movement toward the intact spindle pole in wild-type and klp5Δ cells, suggesting that kinetochore movement is driven by pulling forces. Our theoretical model with Langevin description of microtubule dynamic instability shows that kinesin-8 motors are required for kinetochore centering, whereas sensitivity of rescue to force is necessary for the generation of oscillations. We found that irregular kinetochore movements occur for a broader range of parameters than regular oscillations. Thus, our work provides an explanation for how regulation of microtubule dynamic instability contributes to kinetochore congression and the accompanying movements around the spindle center.
Matrix stiffness modulates infection of endothelial cells byListeria monocytogenesvia expression of cell surface vimentin
Authors: Bastounis Effie E. , Yeh Yi-Ting , Theriot Julie A.
Published: May 2018

Extracellular matrix stiffness (ECM) is one of the many mechanical forces acting on mammalian adherent cells and an important determinant of cellular function. While the effect of ECM stiffness on many aspects of cellular behavior has been studied previously, how ECM stiffness might mediate susceptibility of host cells to infection by bacterial pathogens is hitherto unexplored. To address this open question, we manufactured hydrogels of varying physiologically relevant stiffness and seeded human microvascular endothelial cells (HMEC-1) on them. We then infected HMEC-1 with the bacterial pathogen Listeria monocytogenes (Lm) and found that adhesion of Lm to host cells increases monotonically with increasing matrix stiffness, an effect that requires the activity of focal adhesion kinase (FAK). We identified cell surface vimentin as a candidate surface receptor mediating stiffness-dependent adhesion of Lm to HMEC-1 and found that bacterial infection of these host cells is decreased when the amount of surface vimentin is reduced. Our results provide the first evidence that ECM stiffness can mediate the susceptibility of mammalian host cells to infection by a bacterial pathogen.
Travel Writing in the Age of Globalization
Authors: Graulund Rune
Published: May 2018

Globalization and global travel have existed for centuries. It is over the past century in particular, however, that travel has become truly global, in the sense that most and not just some travel can in some way or other be said to globalized. Indeed, with the invention and spread of new technologies of mobility (like jet travel), and new technologies of information (like the internet), as with the increasingly invasive impact of human activity on the planet at large (like global warming), it is difficult to conceive of travel in the 21st century that is purely “local.” Travel in the age of globalization, then, is at one and the same time both more widespread yet also more irrelevant than ever. As humans, goods, and information move around in ever-increasing quantities, and at ever-greater speed, it seems that mobility is at an all-time high in human history. On the other hand, as a rising number of people and places are interlinked through ever-faster travel and various forms of communication technologies, the local and the global are becoming harder and harder to distinguish.

In this, travel writing has faced a range of challenges that are both old and new. With contemporary travel writers facing a global reality that is very different from the colonial legacy of a traditionally Eurocentric genre, travel writers in the age of globalization have been forced to radically reconsider the itineraries, the destinations, the purpose, and the identity of the traveling subject. Traditionally defined as a white (European) male, the global traveler of the 21st century can take on many forms in terms of race, gender, sexuality, and nationality. At the same time, however, a large number of contemporary travel writers have found it hard to break with the mold of old, desperately continuing to pursue the exotic adventure and the untouched “otherness” of the blank spaces of a map that, in the age of Google Earth, satellite navigation, jet and space travel, global warming, and an explosive growth in human population, are no more.
Morrissey as Latina/o Literary and Cultural Icon
Authors: Hidalgo Melissa M.
Published: May 2018

Morrissey is a singer and songwriter from Manchester, England. He rose to prominence as a popular-music icon as the lead singer for the Manchester band The Smiths (1982–1987). After the breakup of The Smiths, Morrissey launched his solo career in 1988. In his fourth decade as a popular singer, Morrissey continues to tour the world and sell out shows in venues throughout Europe and the United Kingdom, Asia and Australia, and across North and South America. Although Morrissey enjoys a fiercely loyal global fan base and inspires fans all over the world, his largest and most creatively expressive fans, arguably, are Latinas/os in the United States and Latin America. He is especially popular in Mexico and with Chicanas/os from Los Angeles, California, to San Antonio, Texas. How does a white singer and pop icon from England become an important cultural figure for Latinas/os? This entry provides an overview of Morrissey’s musical and cultural importance to fans in the United States–Mexico borderlands. It introduces Morrissey, examines the rise of Latina/o Morrissey and Smiths fandom starting in the 1980s and 1990s, and offers a survey of the fan-produced literature and other cultural production that pay tribute to the indie-music star. The body of fiction, films, plays, poetry, and fans’ cultural production at the center of this entry collectively represent of Morrissey’s significance as a dynamic and iconic cultural figure for Latinas/os.
Communication Technology and Knowledge Management
Authors: Treem Jeffrey
Published: May 2018

In recent years, organizations have greatly increased their use of communication technologies to support knowledge management initiatives. These technologies, commonly referred to as knowledge management systems, are adopted in the hope that they will bolster organizations’ access to, and utilization of, knowledge resources. Yet the relationship between communication technology and knowledge management is complicated by ambiguity regarding whether knowledge can be validly captured, stored, and transmitted in an explicit form (as an object) or only exists in applications (as an action). Many scholars argue that reliance on communication technologies for knowledge management aids the ability of organizations to process information, but it has limited benefits for helping individuals gain situated knowledge regarding how best to accomplish work. An alternative view explores the potential of communication technologies to facilitate interaction among knowledgeable actors, which can support ongoing organizational learning. In practice, the use of communication technologies enacts a duality whereby knowledge operates both as an object that organizations and individuals have, and as an applied action that is used to solve situated problems. Numerous theoretical frameworks have been applied to study the relationship between communication technologies and knowledge management, with three of the most prominent being public goods theory, communities of practice, and transactive memory systems theory. Extant research recognizes the diverse ways that communication technologies can support knowledge management practices aimed at either improving the utilization of information in organizations or bolstering opportunities for interpersonal knowledge sharing. Regardless of the position taken regarding the most appropriate and effective ways that communication technology can support knowledge management, organizations hoping to implement knowledge management systems face numerous challenges related to spurring the creation of organizational knowledge, motivating individuals to share knowledge, transferring knowledge among groups, and storing knowledge to allow future retrieval. Furthermore, the breadth and diversity of communication technologies used for knowledge management will continue to expand as organizations explore the potential applications of social media technologies and seek to gain value from increases in available data regarding individuals’ communication and behaviors.
Humor in Health and Risk Messaging
Authors: Meyer John C. , Venette Steven J.
Published: May 2018

Humor is ubiquitous in communication and is thus worthy of study as part of messages relating to risks and health. Humor’s widely acknowledged effects invite systematic explanation and application by communication scholars interested in health and risk communication. Humor’s influence upon health and risk messages results from the theories of humor origin (incongruity, superiority, and relief), elements of humor perception (unifying or comic perspectives as opposed to tragic or divisive perspectives), and humor functions in social interactions (identification, clarification, enforcement, and differentiation). Humor can be used in messages to mitigate high ego involvement, high levels of fear, and a low sense of efficacy in terms of ability to respond to risk or health messages. Humor can serve to enhance relationships, allowing for more creative discussion of risks and health improvement, yet also can serve to pointedly tease or express a memorable perspective to capture attention regarding a risk or health issue.
Materialist Rhetoric
Authors: McCann Bryan J.
Published: May 2018

The term materialist rhetoric refers to scholarly approaches that seek to account for the relationship between rhetoric and the world that it inhabits. Rhetoricians have differed sharply on the character of this relationship and how it should inform rhetorical theory, criticism, and practice. To be a materialist is to insist that there exists a world outside of human agency that exerts force on human affairs. Marxism is the most influential philosophical tradition for materialist rhetoric, although rhetoricians vary in terms of their adherence to and interpretation of its principles. Karl Marx argued that the antagonistic class relations at the core of capitalism were the chief material determinant for social being. Historical materialism is the primary methodology of Marxist critique, and it rests on the premise that the character of class relations is not governed solely by human volition. Rather, these relations create the conditions of possibility for and shape the trajectory of social life.

While Marxism has informed the liveliest debates regarding materialist rhetoric, not all materialist rhetoricians are Marxists. The earliest iterations of materialist rhetoric drew on Marxism for inspiration, but did not adopt an explicitly anticapitalist orientation. Rather, materialist rhetoric initially referred to calls for rhetoricians to better account for the material character of rhetoric itself. Later developments in materialist rhetoric emerged from debates regarding the nature of Marxism as a rhetorical method, the question of whether rhetoric is representational or constitutive, the character of rhetorical agency, and the existence of a knowable material world outside of rhetoric. Classical Marxists in rhetoric have argued that scholars should predicate their work on the presumption of an experiential reality outside of discourse that exerts force on human symbolic activity. They argue that grounding rhetorical critique in a nondiscursive materiality is necessary for ethical judgment and political practice. Others who reject classical Marxism embrace the claim that rhetoric is material—so much so, in fact, that it comprises every dimension of social being.

Debates between these perspectives hinge largely on how different scholars theorize contemporary capitalism. Whereas classical Marxists retain faith in the revolutionary agency of the working class, their critics contend that rhetoric itself has become the central modality of labor in the modern economy and, therefore, the chief resource for resistance. Other materialist perspectives do not dwell on theoretical debates regarding Marxism, but instead attend to other dimensions of being beyond human symbol use. Whereas some scholars are interested in rhetoric’s relationship to the human body and physical spaces, others theorize rhetoric in ways that reach beyond the limits of human cognition.
Angela Y. Davis and Communication Studies
Authors: Squires Catherine R.
Published: May 2018

Angela Yvonne Davis is an American-born, internationally acclaimed intellectual, activist, and icon. Davis’s groundbreaking work and generative theorizing synthesizes Marxist, feminist, critical race, and cultural studies to illuminate workings of power. Her many books, articles, and essays pose crucial questions that have inspired the work of generations of scholars, cultural workers, and activists. Spanning from the late 1960s to the early 21st century, her writings and speeches have provided rich understandings of history, justice, representation, identity, and resistance.