bluuebunny/crossref_metadata_2025 huggingface dataset:
Pediatric Cochlear Implant Mapping Via Telepractice
Authors: Hughes Michelle L. , Goehring Jenny L. , Miller Margaret K. , Robinson Sara N.
Published: April 2016

Several studies have empirically examined the feasibility and outcomes of remote programming for adults with cochlear implants. Results indicate that equivalent programming levels can be obtained in both the remote and in-person conditions, suggesting that distance technology is a viable alternative to traditional in-person programming methods. Young children, however, require different audiological testing methods to obtain the behavioral responses necessary for speech-processor programming. No studies have empirically evaluated the use of remote programming with the behavioral methods specific to testing young children. Further, young children present additional challenges to behavioral testing (e.g., ability to condition or cooperate) that can lead to the need for additional visits beyond those required for regular programming. This paper describes the potential benefits of remote programming over those achieved for adults, and describes the study design and preliminary results from our current study aimed at validating the use of remote processor programming for young children with cochlear implants (CIs).
Monolithic nanoporous copper fabricated through decomposition and sintering of oxalate
Authors: Li Bing , Li Mingyu , Zeng Qingxuan , Wu Xingyu
Published: April 2016

Two more simple methods were used for preparation of the monolithic nanoporous copper. One was that through decomposition and sintering of copper oxalate precipitate directly. The other was that through decomposition and sintering of copper oxalate and manganese oxalate. The effects of sintered temperature and holding time on the morphology of the monolithic nanoporous copper were investigated. Thermal decomposition, composition and morphology of copper oxalate precipitate, as well as microscopic morphology and specific surface area of the monolithic nanoporous copper were analysed by thermogravimetric analysis, X‐ray diffraction, scanning electron microscope and nitrogen adsorption–desorption. The preferable nanoporous copper can be prepared by decomposition and sintering of copper oxalate directly at 400°C for 30 min. The prepared monolithic nanoporous copper is of open and interconnected pores and is made up of copper grains with the size of about 100 nm, which is as high as 69.9 m2 g−1 in specific surface area.
Assessment of Hemophilic Arthropathy by Ultrasound: Where Do We Stand?
Authors: Di Minno Matteo , Ambrosino Pasquale , Quintavalle Gabriele , Coppola Antonio , Tagliaferri Annarita , Martinoli Carlo , Rivolta Gianna
Published: April 2016

Joint hemorrhages represent the most common type of bleeding episode in persons with hemophilia, and recurrent hemarthrosis triggers chronic arthropathy, which is the most frequent chronic complication in these patients. In recent years, in the frame of a comprehensive care approach, a growing attention has been given to the periodic assessment of the joint status in hemophilia patients with the aim to identify early arthropathic changes and to prevent the development of a clinically overt arthropathy. Besides clinical examination, X-ray and magnetic resonance imaging (MRI) are currently used to evaluate joint status and to monitor the disease progression in hemophilia. Considering the limitations of X-ray and MRI, growing interest has been given to ultrasound (US) as a possible tool to assess joint status and identify early arthropathic changes in hemophilia patients. In the present review, we summarize major literature evidence on the use of joint US for the evaluation of markers of disease activity (joint effusion and synovial hypertrophy) and of degenerative damages (osteochondral changes) in patients with hemophilia. On the whole, being able to identify the presence of intra- or extra-articular fluid, US examination is the fastest and most reliable technique to identify acute conditions, such as hemarthrosis. In addition, the information on joint involvement provided by US in the patient follow-up may influence treatment decisions on a personalized basis. The use of US as part of a routine clinical examination by hemophilia experts may optimize the diagnostic workflow, avoiding additional costs and long waiting lists for patients referred to imaging departments. In the frame of a comprehensive care approach, US might represent a strategy to early detect and monitor synovial hypertrophy and osteochondral changes in hemophilia, thus extending the clinical examination and helping identify joints to be studied with a second-level examination such as MRI.
VR-SCOSMO: A smooth conductor-like screening model with charge-dependent radii for modeling chemical reactions
Authors: Kuechler Erich R. , Giese Timothy J. , York Darrin M.
Published: April 2016

To better represent the solvation effects observed along reaction pathways, and of ionic species in general, a charge-dependent variable-radii smooth conductor-like screening model (VR-SCOSMO) is developed. This model is implemented and parameterized with a third order density-functional tight binding quantum model, DFTB3/3OB-OPhyd, a quantum method which was developed for organic and biological compounds, utilizing a specific parameterization for phosphate hydrolysis reactions. Unlike most other applications with the DFTB3/3OB model, an auxiliary set of atomic multipoles is constructed from the underlying DFTB3 density matrix which is used to interact the solute with the solvent response surface. The resulting method is variational, produces smooth energies, and has analytic gradients. As a baseline, a conventional SCOSMO model with fixed radii is also parameterized. The SCOSMO and VR-SCOSMO models shown have comparable accuracy in reproducing neutral-molecule absolute solvation free energies; however, the VR-SCOSMO model is shown to reduce the mean unsigned errors (MUEs) of ionic compounds by half (about 2-3 kcal/mol). The VR-SCOSMO model presents similar accuracy as a charge-dependent Poisson-Boltzmann model introduced by Hou et al. [J. Chem. Theory Comput. 6, 2303 (2010)]. VR-SCOSMO is then used to examine the hydrolysis of trimethylphosphate and seven other phosphoryl transesterification reactions with different leaving groups. Two-dimensional energy landscapes are constructed for these reactions and calculated barriers are compared to those obtained from ab initio polarizable continuum calculations and experiment. Results of the VR-SCOSMO model are in good agreement in both cases, capturing the rate-limiting reaction barrier and the nature of the transition state.
Self-interaction corrections applied to Mg-porphyrin, C60, and pentacene molecules
Authors: Pederson Mark R. , Baruah Tunna , Kao Der-you , Basurto Luis
Published: April 2016

We have applied a recently developed method to incorporate the self-interaction correction through Fermi orbitals to Mg-porphyrin, C60, and pentacene molecules. The Fermi-Löwdin orbitals are localized and unitarily invariant to the Kohn-Sham orbitals from which they are constructed. The self-interaction-corrected energy is obtained variationally leading to an optimum set of Fermi-Löwdin orbitals (orthonormalized Fermi orbitals) that gives the minimum energy. A Fermi orbital, by definition, is dependent on a certain point which is referred to as the descriptor position. The degree to which the initial choice of descriptor positions influences the variational approach to the minimum and the complexity of the energy landscape as a function of Fermi-orbital descriptors is examined in detail for Mg-porphyrin. The applications presented here also demonstrate that the method can be applied to larger molecular systems containing a few hundred electrons. The atomization energy of the C60 molecule within the Fermi-Löwdin-orbital self-interaction-correction approach is significantly improved compared to local density approximation in the Perdew-Wang 92 functional and generalized gradient approximation of Perdew-Burke-Ernzerhof functionals. The eigenvalues of the highest occupied molecular orbitals show qualitative improvement.
Nanosecond X-ray detector based on high resistivity ZnO single crystal semiconductor
Authors: Zhao Xiaolong , Chen Liang , He Yongning , Liu Jinliang , Peng Wenbo , Huang Zhiyong , Qi Xiaomeng , Pan Zijian , Zhang Wenting , Zhang Zhongbing , Ouyang Xiaoping
Published: April 2016

The pulse radiation detectors are sorely needed in the fields of nuclear reaction monitoring, material analysis, astronomy study, spacecraft navigation, and space communication. In this work, we demonstrate a nanosecond X-ray detector based on ZnO single crystal semiconductor, which emerges as a promising compound-semiconductor radiation detection material for its high radiation tolerance and advanced large-size bulk crystal growth technique. The resistivity of the ZnO single crystal is as high as 1013 Ω cm due to the compensation of the donor defects (VO) and acceptor defects (VZn and Oi) after high temperature annealing in oxygen. The photoconductive X-ray detector was fabricated using the high resistivity ZnO single crystal. The rise time and fall time of the detector to a 10 ps pulse electron beam are 0.8 ns and 3.3 ns, respectively, indicating great potential for ultrafast X-ray detection applications.
Urchin-like artificial gallium oxide nanowires grown by a novel MOCVD/CVD-based route for random laser application
Authors: de Melo Ronaldo P. , Oliveira Nathalia Talita C. , Dominguez Christian Tolentino , Gomes Anderson S. L. , Falcão Eduardo H. L. , Alves Severino , da Luz Leonis L. , Chassagnon Remi , de Araújo Cid B. , Sacilotti Marco
Published: April 2016

A novel procedure based on a two-step method was developed to obtain β-Ga2O3 nanowires by the chemical vapor deposition (CVD) method. The first step consists in the gallium micro-spheres growth inside a metal-organic chemical vapor deposition environment, using an organometallic precursor. Nanoscale spheres covering the microspheres were obtained. The second step involves the CVD oxidization of the gallium micro-spheres, which allow the formation of β-Ga2O3 nanowires on the micro-sphere surface, with the final result being a nanostructure mimicking nature's sea urchin morphology. The grown nanomaterial is characterized by several techniques, including X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, and photoluminescence. A discussion about the growth mechanism and the optical properties of the β-Ga2O3 material is presented considering its unknown true bandgap value (extending from 4.4 to 5.68 eV). As an application, the scattering properties of the nanomaterial are exploited to demonstrate random laser emission (around 570 nm) when it is permeated with a laser dye liquid solution.
Review of laser produced multi-keV X-ray sources from metallic foils, cylinders with liner, and low density aerogels
Authors: Girard Frédéric
Published: April 2016

Experimental results obtained within the last fifteen years on multi-keV X-ray sources irradiated with nanosecond scale pulse duration 3ω laser light at TW power levels by CEA and collaborators are discussed in this review paper. Experiments were carried out on OMEGA and GEKKO XII laser facilities where emitting materials in the 5–10 keV multi-keV energy range are intermediate Z value metals from titanium to germanium. Results focused on conversion efficiency improvement by a factor of 2 when an underdense plasma is created using a laser pre-pulse on a metallic foil, which is then heated by a second laser pulse delayed in time. Metal coated inner surface walls of plastic cylindrical tube ablated by laser beam impacts showed that plasma confinement doubles X-ray emission duration as it gives adequate plasma conditions (electron temperature and density) over a long period of time. Low-density aerogels (doped with metal atoms uniformly distributed throughout their volume or metal oxides) contained in a plastic cylinder have been developed and their results are comparable to gas targets. A hybrid target concept consisting of a thin metal foil placed at the end of a cylinder filled with low density aerogel has emerged as it could collect benefits from pre-exploded thin foils, efficient laser absorption in aerogel, and confinement by cylinder walls. All target geometry performances are relatively close together at a given photon energy and mainly depend on laser irradiation condition optimizations. Results are compared with gas target performances from recent NIF experiments allowing high electron temperatures over large dimension low density plasmas, which are the principal parameters for efficient multi-keV X-ray production.
A highly flexible electrochemical flow cell designed for the use of model electrode materials on non-conventional substrates
Authors: Temmel S. E. , Tschupp S. A. , Schmidt T. J.
Published: April 2016

We present a novel electrochemical flow cell based on a wall-jet configuration to carry out electrochemical investigations under controlled mass transport conditions. The described setup can be applied for investigations similar to those performed with a common rotating disc electrode setup but allows the use of non-conductive and square substrates. This setup thus opens the possibility for the characterization of a new range of materials on a broad range of substrates. Cyclic voltammograms were recorded to assess the cleanliness and good saturation of the cell with inert gas. The performance of the flow cell regarding hydrodynamic experiments was evaluated by probing the oxygen reduction reaction on differently prepared platinum catalysts, including Pt on non-conductive substrates. The high reproducibility of the limiting currents for these samples demonstrates the good functionality, adaptability, and flexibility of the cell.
Communication: Linking the dielectric Debye process in mono-alcohols to density fluctuations
Authors: Hecksher Tina
Published: April 2016

This work provides the first direct evidence that the puzzling dielectric Debye process observed in mono-alcohols is coupled to density fluctuations. The results open up for an explanation of the Debye process within the framework of conventional liquid-state theory. The spectral shape of the dynamical bulk modulus of the two studied mono-alcohols, 2-ethyl-1-hexanol and 4-methyl-3-heptanol, is nearly identical to that of their corresponding shear modulus, and thus the supramolecular structures believed to be responsible for the slow dielectric Debye process are manifested in the bulk modulus in the same way as in the shear modulus.
Communication: Three-fold covariance imaging of laser-induced Coulomb explosions
Authors: Pickering James D. , Amini Kasra , Brouard Mark , Burt Michael , Bush Ian J. , Christensen Lauge , Lauer Alexandra , Nielsen Jens H. , Slater Craig S. , Stapelfeldt Henrik
Published: April 2016

We apply a three-fold covariance imaging method to analyse previously acquired data [C. S. Slater et al., Phys. Rev. A 89, 011401(R) (2014)] on the femtosecond laser-induced Coulomb explosion of spatially pre-aligned 3,5-dibromo-3′,5′-difluoro-4′-cyanobiphenyl molecules. The data were acquired using the “Pixel Imaging Mass Spectrometry” camera. We show how three-fold covariance imaging of ionic photofragment recoil trajectories can be used to provide new information about the parent ion’s molecular structure prior to its Coulomb explosion. In particular, we show how the analysis may be used to obtain information about molecular conformation and provide an alternative route for enantiomer determination.
Multistage depressed collector conceptual design for thin magnetically confined electron beams
Authors: Pagonakis Ioannis Gr. , Wu Chuanren , Illy Stefan , Jelonnek John
Published: April 2016

The requirement of higher efficiency in high power microwave devices, such as traveling wave tubes and gyrotrons, guides scientific research to more advanced types of collector systems. First, a conceptual design approach of a multistage depressed collector for a sheet electron beam confined by a magnetic field is presented. The sorting of the electron trajectories, according to their initial kinetic energy, is based on the E × B drift concept. The optimization of the geometrical parameters is based on the analytical equations under several general assumptions. The analysis predicts very high levels of efficiency. Then, a design approach for the application of this type of collector to a gyrotron cylindrical hollow electron beam is also presented with very high levels of efficiency more than 80%.
Generation of electromagnetic ion cyclotron waves in the near-Earth magnetotail during dipolarization: Two-dimensional global hybrid simulation
Authors: Guo Zhifang , Wu Mingyu , Du Aimin
Published: April 2016

We employ two-dimensional global hybrid simulations to study the generation, propagation, and polarization of electromagnetic ion cyclotron (EMIC) waves in the near-Earth magnetotail (around x=−10RE) during dipolarization. In our simulation, EMIC waves with left-hand polarized signals originate in the low-latitude magnetotail as a result of the ion temperature anisotropy which is due to ion heating by Alfvén waves. Subsequently, EMIC waves can propagate along the ambient magnetic field toward high-latitudes. Our work provides one possible mechanism for the generation of EMIC waves observed in the near-Earth magnetotail.
Reduced graphene oxide filled poly(dimethyl siloxane) based transparent stretchable, and touch-responsive sensors
Authors: Ponnamma Deepalekshmi , Sadasivuni Kishor Kumar , Cabibihan John-John , Yoon W. Jong , Kumar Bijandra
Published: April 2016

The ongoing revolution in touch panel technology and electronics demands the need for thin films, which are flexible, stretchable, conductive, and highly touch responsive. In this regard, conductive elastomer nanocomposites offer potential solutions for these stipulations; however, viability is limited to the poor dispersion of conductive nanomaterials such as graphene into the matrix. Here, we fabricated a reduced graphene oxide (rGO) and poly(dimethylsiloxane) (PDMS) elastomer based transparent and flexible conductive touch responsive film by dispersing rGO honeycombs uniformly into PDMS elastomer through an ionic liquid (IL) modification. Pursuing a simple, scalable, and safe method of solution casting, this provides a versatile and creative design of a transparent and stretchable rGO/IL-PDMS capacitive touch responsive, where rGO acts as a sensing element. This transparent film with ∼70% transmittance exhibits approximately a five times faster response in comparison to rGO/PDMS film, with negligible degradation over time. The performance of this touch screen film is expected to have applications in the emerging field of foldable electronics.
Lateral shearing optical gradient force in coupled nanobeam photonic crystal cavities
Authors: Du Han , Zhang Xingwang , Deng Jie , Zhao Yunshan , Chau Fook Siong , Zhou Guangya
Published: April 2016

We report the experimental observation of lateral shearing optical gradient forces in nanoelectromechanical systems (NEMS) controlled dual-coupled photonic crystal (PhC) nanobeam cavities. With an on-chip integrated NEMS actuator, the coupled cavities can be mechanically reconfigured in the lateral direction while maintaining a constant coupling gap. Shearing optical gradient forces are generated when the two cavity centers are laterally displaced. In our experiments, positive and negative lateral shearing optical forces of 0.42 nN and 0.29 nN are observed with different pumping modes. This study may broaden the potential applications of the optical gradient force in nanophotonic devices and benefit the future nanooptoelectromechanical systems.
The evolution mechanism of defect dipoles and high strain in MnO2-doped KNN lead-free ceramics
Authors: Zhao Zhihao , Dai Yejing , Li Xiaolei , Zhao Zhe , Zhang Xiaowen
Published: April 2016

Defect dipoles in acceptor-doped (K0.5Na0.5)NbO3-based ceramics have a significant influence on their electrical properties. The present study examined the influence of the sintering atmosphere on the electrical properties of MnO2-doped (K0.5Na0.5)NbO3. The poled and aged samples sintered in the Ar atmosphere depicted unusual behavior related to the formation of defect dipoles (Mn2+Nb‴−VO··)′, aligned in the poling direction having larger polarity. The S-E loop of the poled and aged MnO2-doped (K0.5Na0.5)NbO3 ceramics sintered in the Ar atmosphere revealed larger strains in the poling direction and restrained strains in the opposite direction. Furthermore, it is observed that the unipolar electro-strain could reach 0.28% (d33* = 800 pm/V) at 3.5 kV/mm, a value nearly 5.6-fold higher than those obtained in the air atmosphere (0.05%). This method based on the sintering atmosphere and process control provides a promising way to obtain substantial electro-strain values suitable for applications in high-displacement actuators.
Photosensitivity of p-type black Si field emitter arrays
Authors: Mingels S. , Porshyn V. , Prommesberger C. , Langer C. , Schreiner R. , Lützenkirchen-Hecht D. , Müller G.
Published: April 2016

We have investigated the properties of black Si field emitter arrays under strong electric fields and laser illumination. A low onset field of 1.8 MV/m for an emission current of 1 nA was obtained. A pronounced saturation region of the dark and photo-enhanced current was observed, which provided a short-term stability of 0.1% at 0.4 μA and 0.7% at 1.0 μA, respectively. As maximum value for the photosensitivity, an on-off current switching ratio of 43 reaching about 13 μA was achieved at a laser power of 15 mW. Electron spectra in the dark and under laser illumination are presented, showing a current and light-sensitive voltage drop across the emitters as well as hints for hot electron emission.
Effects of oxygen plasma etching on Sb2Te3 explored by torque detected quantum oscillations
Authors: Yan Yuan , Heintze Eric , Pracht Uwe S. , Blankenhorn Marian , Dressel Martin
Published: April 2016

De Haas–van Alphen measurements evidence that oxygen plasma etching strongly affects the properties of the three-dimensional topological insulator Sb2Te3. The quantum oscillations in magnetization down to low temperature (T ≥ 2 K) and high magnetic field (B ≤ 7 T) have been systematically investigated using a high-sensitive cantilever torque magnetometer. The effective mass and the oscillation frequency obtained from de Haas–van Alphen measurements first increase and then decrease as the oxygen plasma etching time increases from 0 to 12 min, corresponding to an up- and down-shift of the Dirac point. We establish the cantilever torque magnetometer as a powerful contactless tool to investigate the oxygen sensitivity of the surface state in topological insulators.
Solid phase epitaxial growth of high mobility La:BaSnO3 thin films co-doped with interstitial hydrogen
Authors: Niedermeier Christian A. , Rhode Sneha , Fearn Sarah , Ide Keisuke , Moram Michelle A. , Hiramatsu Hidenori , Hosono Hideo , Kamiya Toshio
Published: April 2016

This work presents the solid phase epitaxial growth of high mobility La:BaSnO3 thin films on SrTiO3 single crystal substrates by crystallization through thermal annealing of nanocrystalline thin films prepared by pulsed laser deposition at room temperature. The La:BaSnO3 thin films show high epitaxial quality and Hall mobilities up to 26 ± 1 cm2/Vs. Secondary ion mass spectroscopy is used to determine the La concentration profile in the La:BaSnO3 thin films, and a 9%–16% La doping activation efficiency is obtained. An investigation of H doping to BaSnO3 thin films is presented employing H plasma treatment at room temperature. Carrier concentrations in previously insulating BaSnO3 thin films were increased to 3 × 1019 cm−3 and in La:BaSnO3 thin films from 6 × 1019 cm−3 to 1.5 × 1020 cm−3, supporting a theoretical prediction that interstitial H serves as an excellent n-type dopant. An analysis of the free electron absorption by infrared spectroscopy yields a small (H,La):BaSnO3 electron effective mass of 0.27 ± 0.05 m0 and an optical mobility of 26 ± 7 cm2/Vs. As compared to La:BaSnO3 single crystals, the smaller electron mobility in epitaxial thin films grown on SrTiO3 substrates is ascribed to threading dislocations as observed in high resolution transmission electron micrographs.
Communication: Electron ionization of DNA bases
Authors: Rahman M. A. , Krishnakumar E.
Published: April 2016

No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve the existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.
Enhancing modelled water content by dielectric permittivity in stony soils
Authors: Pakparvar M. , Cornelis W. , Gabriels D. , Mansouri Z. , Kowsar S. A.
Published: April 2016

Applicability of time domain reflectometry (TDR) under naturally distributed stone fragments in soils has seldom been investigated. A multilayer profile of a 30-m-deep well was sampled and the natural distribution of stone fragments in the soils was replicated in the laboratory. Gravimetric soil water content (SWC) was measured simultaneously with TDR dielectric permittivity (Ka) readings and bulk densities in three subsamples as replications. Two connector and buriable probes and three reflection-time capture windows (10, 20 and 40 ns) were used for the measurements. These were repeated for sieved soil samples <2 mm with fixed, pre-measured bulk densities. Measurements of Ka and observed SWC were repeated for extension-cable lengths of 3–30 m. All measurements were taken in samples saturated from the bottom. A semi-empirical mixture model was applied for different fractions of stony samples in order to convert bulk Ka to bulk volumetric SWC (θv) by the mixture model (θvmx), to be compared with θv by the conventional Topp equation (θvTp). An improvement in model performance was observed with lower root-mean-square error (RMSE, 0.02–0.04 v. 0.07–0.1) and ratio of RMSE to observation standard deviation (0.32–0.87 v. 1.07–3.05) for θvmx compared with θvTp. This approach for converting the in-situ measured dielectric permittivity to the θv of the bulk soil can be applied based on the determined stoniness. The 15-cm, 2-rod (connector) probe type with capture windows 20 ns resulted in a better performance than the 20-cm, 3-rod (buriable) probe type with capture windows 10 and 40 ns. Development of regression equations for the stone-free samples resulted in calibrated equations for converting the measured Ka to θv with better results (RMSE ~0.002 m3 m–3) than those obtained using the Topp equation. In contrast to the traditional equation, new sets of coefficients for the Topp equation were also capable of estimating extremely low θv values of ≤0.02 m3 m–3 where the minimum calculated θv values were adequately similar to the observed ones. Noticeable effects of cable length on measured Ka were found for lengths exceeding 10 m. Accurate Ka values might be obtained in similar soil conditions if the suggested regression equations are employed, provided a correction is made for the extension cables.
The reversal test, status quo bias, and opposition to human cognitive enhancement
Authors: Clarke Steve
Published: April 2016

Bostrom and Ord’s reversal test has been appealed to by many philosophers to substantiate the charge that preferences for status quo options are motivated by status quo bias. I argue that their characterization of the reversal test needs to be modified, and that their description of the burden of proof it imposes needs to be clarified. I then argue that there is a way to meet that burden of proof which Bostrom and Ord fail to recognize. I also argue that the range of circumstances in which the reversal test can be usefully applied is narrower than they recognize.
Coordinated process of polarized growth in filamentous fungi
Authors: Takeshita Norio
Published: April 2016

Filamentous fungi are extremely polarized organisms, exhibiting continuous growth at their hyphal tips. The hyphal form is related to their pathogenicity in animals and plants, and their high secretion ability for biotechnology. Polarized growth requires a sequential supply of proteins and lipids to the hyphal tip. This transport is managed by vesicle trafficking via the actin and microtubule cytoskeleton. Therefore, the arrangement of the cytoskeleton is a crucial step to establish and maintain the cell polarity. This review summarizes recent findings unraveling the mechanism of polarized growth with special emphasis on the role of actin and microtubule cytoskeleton and polarity marker proteins. Rapid insertions of membranes via highly active exocytosis at hyphal tips could quickly dilute the accumulated polarity marker proteins. Recent findings by a super-resolution microscopy indicate that filamentous fungal cells maintain their polarity at the tips by repeating transient assembly and disassembly of polarity sites.
α-Actinin links extracellular matrix rigidity-sensing contractile units with periodic cell-edge retractions
Authors: Meacci Giovanni , Wolfenson Haguy , Liu Shuaimin , Stachowiak Matthew R. , Iskratsch Thomas , Mathur Anurag , Ghassemi Saba , Gauthier Nils , Tabdanov Erdem , Lohner James , Gondarenko Alexander , Chander Ashok C. , Roca-Cusachs Pere , O’Shaughnessy Ben , Hone James , Sheetz Michael P.
Published: April 2016

During spreading and migration, the leading edges of cells undergo periodic protrusion–retraction cycles. The functional purpose of these cycles is unclear. Here, using submicrometer polydimethylsiloxane pillars as substrates for cell spreading, we show that periodic edge retractions coincide with peak forces produced by local contractile units (CUs) that assemble and disassemble along the cell edge to test matrix rigidity. We find that, whereas actin rearward flow produces a relatively constant force inward, the peak of local contractile forces by CUs scales with rigidity. The cytoskeletal protein α-actinin is shared between these two force-producing systems. It initially localizes to the CUs and subsequently moves inward with the actin flow. Knockdown of α-actinin causes aberrant rigidity sensing, loss of CUs, loss of protrusion–retraction cycles, and, surprisingly, enables the cells to proliferate on soft matrices. We present a model based on these results in which local CUs drive rigidity sensing and adhesion formation.
Neurophysiology of Multiple Sclerosis
Authors: Slimp Jefferson C.
Published: April 2016

Any discussion of the pathomechanisms and treatments of MS benefits from an understanding of the physiology of the neuronal membrane and the action potential. Neurons and glia, are important for signal propagation, synaptic function, and neural development. The neuronal cell membrane, maintains different ionic environments inside and outside the cell, separating charge across the membrane and facilitating electrical excitability. Ion channels allow flow of sodium, potassium, and calcium ions across the membrane at selected times. At rest, potassium ion efflux across the membrane establishes the nerve membrane resting potential. When activated by a voltage change to threshold, sodium influx generates an action potential, or a sudden alteration in membrane potentials, that can be conducted along an axon. The myelin sheaths around an axon, increase the speed of conduction and conserve energy. The pathology of MS disrupts the myelin structures, disturbs conduction, and leads to neurodegeneration. Ion channels have been the target of investigation for both restoration of conduction and neuroprotection.
Immunology of Multiple Sclerosis
Authors: Piccio Laura , Cross Anne H.
Published: April 2016

Multiple sclerosis (MS) is considered to be an autoimmune disease of the central nervous system that targets myelin but affects both white matter and gray matter. Multiple sclerosis is thought to be mediated by cells of the adaptive and innate immune systems. CD4+ T lymphocytes of the Th1 and Th17 subtypes are believed to be critical for the initiation of multiple sclerosis. Treatment with monoclonal antibodies that deplete B lymphocytes has proven that B cells are critical to relapse development in multiple sclerosis. While immunopathophysiology is clearly important in MS, whether multiple sclerosis is truly an autoimmune disorder and the target or targets of the autoimmunity remain unknown.
Diagnosis of Multiple Sclerosis
Authors: Rolak Loren A.
Published: April 2016

Because no laboratory test or imaging study is both highly sensitive and highly specific for multiple sclerosis, some uncertainty often accompanies the diagnosis. Various guidelines have been developed to assist the clinician, including the much-modified and commonly used McDonald criteria. Typical features of the history, the physical examination, and magnetic resonance imaging findings usually allow for a secure diagnosis. However, limitations inherent in any testing modality still pose challenges. This is especially true for diagnosis of primary progressive multiple sclerosis because the sensitivity and specificity of the evaluations are lower.
Evoked Potentials
Authors: Nuwer Marc R.
Published: April 2016

Visual evoked potentials, brainstem auditory evoked potentials, and somatosensory evoked potentials are established clinical tests that are useful for the diagnosis of multiple sclerosis. Motor evoked potentials, cognitive event-related potentials, and vestibular evoked potentials also are used clinically to test additional pathways and functions. These objective, reproducible tools can identify clinically silent lesions, predict clinical deterioration risk, and localize levels of impairment. They differ from magnetic resonance imaging in that they assess function rather than anatomy and thereby fill a complementary role in clinical care. They also are useful in therapeutic trials because they can predict outcomes in parallel with, or earlier than, clinical examinations.
Neuro-ophthalmologic Manifestations of Multiple Sclerosis
Authors: Beh Shin C. , Frohman Elliot M. , Frohman Teresa
Published: April 2016

The inflammatory, demyelinating plaques that characterize multiple sclerosis (MS) frequently affect the visual pathways. Lesions of the afferent visual pathway (most commonly optic neuritis) result in problems conveying visual stimuli from the retina to the visual cortices. Lesions affecting the efferent visual system result in ocular dysmotility that impairs visual acuity by disrupting the precision of binocular eye movements or by causing excessive eye movements that prevent adequate foveation (e.g. nystagmus, saccadic intrusions). Significant advancements have been made in the techniques used to interrogate both the structural and the functional integrity of the visual system to dissect the pathobiological underpinnings of multiple sclerosis and to design better biomarkers and clinical trial outcomes. This chapter discusses the neuro-ophthalmic manifestations of multiple sclerosis, revolutionary advancements in optical coherence tomography and visual electrophysiology, and therapies for treating visual dysfunction in multiple sclerosis.
Cognitive Impairment and Mood Disturbances
Authors: Larocca Nicholas G.
Published: April 2016

This chapter presents a comprehensive review of two of the most prevalent symptoms in persons with multiple sclerosis. While cognitive impairment and mood disorders may affect at least half of the MS population, and can have a significant effect on function and quality of life, they are often under recognized and under treated. The epidemiology and most common clinical manifestations of cognitive dysfunction and mood disorders are presented, along with a detailed discussion of screening and assessment tools. Pharmacologic and behavioral treatment interventions are reviewed, with analyses of their comparative efficacy.
Pediatric Multiple Sclerosis
Authors: Tillema Jan-Mendelt , Graves J. , Benson L. A. , Aaen G. S. , Belman A. , Parrish J. , Weinstock-Guttman B. , Krupp L. , Chitnis T. , Wauban E.
Published: April 2016

Increased interest in pediatric-onset multiple sclerosis (MS) has contributed to improved knowledge of the presentation and evolution of central nervous system demyelinating diseases in childhood. This chapter reviews the unique features and challenges related to pediatric MS. The close proximity of pediatric MS to the biological onset of the disease provides a unique window into disease pathogenesis at stages of life when innate and adaptive immune pathways are still maturing. It is expected that the interplay between genetics, epigenetics, environmental exposures, and the maturing central nervous system in children with MS will provide important insights into the earliest phases of the disease. This chapter reviews the unique features that distinguish pediatric patients with MS from their adult counterparts. Specific emphasis is placed on the work-up and management of these patients in the context of current knowledge.
Living with Multiple Sclerosis
Authors: Kalb Rosalind C.
Published: April 2016

This chapter describes the challenges experienced by individuals and families after diagnosis of multiple sclerosis, as the disease progresses, and in the face of significant disability. Common emotional reactions such as grief, anxiety, anger, and guilt are described, along with specific recommendations for physicians, rehabilitation professionals, and mental health professionals on how to support their patients throughout the disease course. Challenges related to diagnosis, disclosure, and treatment decisions, as well as the variability and unpredictability of the disease are highlighted. Understanding disease progression, communicating one’s needs, and utilizing assistive technology are the focus as the disease progresses. Redefining one’s sense of self, independence, and control are the primary challenges for those with more advanced multiple sclerosis. For families, the recommended interventions are designed to support healthy, balanced care partnerships; address the needs of children and elderly parents; and promote effective planning and problem-solving.
Issues in the Design and Interpretation of Multiple Sclerosis Clinical Trials
Authors: Krieger Stephen , Katz Sand Ilana , Oynhausen Svenja , Miller Aaron
Published: April 2016

This chapter covers important historical, scientific, and current issues in the development of modern clinical trials as well as therapeutic interventions for patients with multiple sclerosis. The chapter includes a review of terminology, methodology, and outcomes employed in clinical trials related to multiple sclerosis. A focus of the chapter is on the limitations of historical and current trial designs, particularly in regard to their application to clinical decision making. This second edition incorporates findings from clinical trials of oral agents and monoclonal antibodies developed for treatment of multiple sclerosis and provides an update on ethical issues in multiple sclerosis clinical research.
Integration of information technology in the ICU
Authors: Martich Daniel , Cervenak Jody
Published: April 2016

As we look to the evolving health care industry with improved care quality, health outcomes, and cost parameters, the demands of the critical care environment require a transformation. Technology, process, and people are at the centre of this transformation. The power is in the knowledge that can be achieved and the process improvements that can be made through automation. Five major areas of technology evolution include workflow automation, information exchange, clinical decision support, and predictive modelling, remote monitoring, and data analytics. If designed properly, technology can result in doing things differently (better) and doing different things. Information exchange is required for quality and efficient critical care information delivery. Data analytics will use information for comparative effectiveness, registry reporting, population management, and research study recruiting.
Multiple casualties and disaster response in critical care
Authors: Weiss Yoram , Shamir Micha
Published: April 2016

Most disasters occur with little or no warning, which emphasizes the importance of being prepared for disasters. This chapter will focus on the organizational steps needed to provide disaster response and operational flexibility, with an emphasis on the importance of a multidisciplinary team approach in the preparation needed to deal with and care patients from for a multiple-casualty event (MCE) following a disaster. Process control issues related to the management of a MCE, such as forward deployment of medical personnel to the trauma bay and emergency room, the establishment of a chain of command to limit chaos, patient flow, and information gathering, will be discussed.
Communication with patients and families in the ICU
Authors: Scheunemann Leslie P. , Arnold Robert M.
Published: April 2016

Regular, consistent communication with families of intensive care unit (ICU) patients is important for family satisfaction, patient-centred decision-making, and reducing the emotional burden of the ICU stay on family members. In fact, the family meeting can appropriately be considered a core procedure of intensive care practice. Good communication requirements include the appropriate clinicians and family members, providing a quiet and undisturbed setting, and choosing appropriate goals for each meeting. Clinicians should strive to develop skills for listening, observing family dynamics, and responding to emotions. ICU administrators should consider building processes of care to promote regular, consistent communication and partnerships with interdisciplinary teams, such as ethics committees and palliative care that can supplement these skills.
Telemedicine in critical care
Authors: Patel Bela , Thomas Eric J.
Published: April 2016

The majority of critically-ill patients are admitted to hospitals that do not have physician intensivist coverage, despite strong evidence that clinical outcomes are improved with intensivist staffing. Telemedicine can leverage clinical resources by providing critical care expertise to patients in intensive care units (ICUs) by off-site clinicians using video, audio, and electronic links. In the past 10 years, telemedicine in critical care has seen tremendous growth in the number of ICU patients being supported by this care model across the USA. The impact of ICU telemedicine coverage has been studied rigorously only in a few studies and the outcomes have been mixed and inconsistent. Telemedicine has been shown in some studies to improve adherence to ICU best practices for the prevention of deep venous thrombosis, stress ulcers, ventilator-associated pneumonia, and catheter-related bloodstream infections. Further research in ICU telemedicine is required to understand the variability of outcomes among the telemedicine programmes studied and to effectively implement the technology to consistently improve outcomes and reduce costs in the critical care environment.
Leadership skills in the ICU
Authors: Foot Carole , Hickson Liz
Published: April 2016

Key theories of leadership are presented. Common themes inherent to the various models are the existence of important specific traits, behaviours, and strategies that are used to influence, facilitate future development, and inspire progress in those being lead. Leadership is differentiated from the related, but distinct concept of management. Leaders are focused on the strategic direction and vision of an organization, while managers are directed towards the co-ordination and stewardship of activities in order to effectively meet predetermined mandates. The importance of these skills in intensive care medicine, the difficulties related to measuring them, and strategies to improve leadership in health care are reviewed.
Managing biohazards and environmental safety
Authors: Kovari Ferenc , Park Gilbert
Published: April 2016

This chapter highlights the most common sources of biohazards in a critical care unit and points out the importance of a safe environment. Detailed information is provided on various biological and chemical agents, including risks posed by radiation. As part of the topic of health care ergonomics, various issues are discussed. Washing hands is the key to reducing biological hazards. Wearing appropriate protective gear minimizes the risk of chemical hazard. Complying with safety rules and attending regular training help avoiding risks resulting from handling dangerous materials, electronic equipment. As a new approach we included the potential risk of psychological factors such as stress and noise.
Managing ICU staff welfare, morale, and burnout
Authors: Lavery Gavin G. , Mottram Linda-Jayne
Published: April 2016

Low morale, stress, and burnout are significant and under-recognized in critical care staff. The link between these conditions is complex and not fully only understood with burnout as a potential end result. Conflict and lack of clear protocols regarding end-of-life care appear to be particularly prone to generate stress and potentially burnout. We have little scientific basis to design interventions, but expert opinion suggests multiple approaches at individual, departmental, and organizational levels. Many are based on giving workers a degree of control and flexibility where possible, and a feeling that their contribution is valuable and valued. Engagement (with an organization and its aims) is now viewed as the antithesis of burnout and only staff who are engaged can deliver high quality care. It is increasingly recognized that organizations that actively manage staff welfare are more likely to provide care that is safe, effective, and patient-centred, and less likely to error and adverse events.
Severity of illness scoring systems
Authors: Hart Graeme K. , Pilcher David
Published: April 2016

Clinical outcome comparisons for research and quality assurance require risk adjustment measures validated in the population of interest. There are many scoring systems using intensive care unit (ICU)-specific or administrative data sets, or both. Risk-adjusted ICU and hospital mortality outcome measures may be not granular enough or may be censored before the absolute risk of the studied outcome reaches that of the population at large. Data linkage methods may be used to examine longer-term outcomes. Organ failure scores provide a method for assessing the intra-episode time course of illness and scores using treatment variables may be useful for assessing care requirements. Each adjustment system has specific merits and limitations, which must be understood for appropriate use. Graphical representations of the comparisons facilitate understanding and time-appropriate response to variations in outcome. There are, as yet, no universally-accepted measures for severity of illness and risk adjustment in deteriorating patients outside the ICU.