bluuebunny/crossref_metadata_2025 huggingface dataset:
Neurologisch-neurochirurgische Frührehabilitation in den Bundesländern Niedersachsen und Bremen
Authors: Roesner Martin , Beyer Joachim , Peter Dohm Christoph , Elsner Matthias , Groß Martin , Meyer Alfons , Mokrusch Thomas , Neunzig Hans-Peter , Thomas Randall , Winkler Christian , Rollnik Jens D.
Published: March 2019

Einleitung Die Untersuchung diente der Erhebung der Versorgungssituation in der neurologisch-neurochirurgischen Frührehabilitation (NNFR) in den Bundesländern Niedersachen (NDS) und Bremen (HB).

Methodik Zur Untersuchung wurden alle Anmeldungen aus Akutkliniken zur NNFR in NDS / HB innerhalb einer Periode von zwei Wochen jeweils im November 2015 und 2016 erfasst und über einen weiteren Beobachtungszeitraum von sechs Wochen der Anteil der davon aufgenommenen Patienten ermittelt. Ebenso wurde ermittelt, welche Faktoren eine Aufnahme zur NNFR in NDS oder HB begünstigen bzw. erschweren.

Ergebnisse Nur 45 % der angemeldeten Patienten konnten in einer Frührehabilitationseinrichtung in NDS / HB aufgenommen werden. Eine Aufnahme wurde deutlich durch das Vorhandensein isolierungspflichtiger Keime erschwert. Insgesamt nur 21 % der mit Problemkeimen besiedelten Patienten konnten aufgenommen werden, bei MRSA (Methicillin-resistenter Staphylococcus aureus) waren es sogar nur 13 %. Nachteilig wirkten sich ebenfalls eine Dialysepflicht (20 %), die Hauptdiagnosen Polyneuropathie / Guillain-Barré-Syndrom (GBS) (33 %) und hypoxischer Hirnschaden (37 %) aus, ebenso das Vorhandensein einer Beatmungspflicht (37 %). Eine leicht überdurchschnittliche Aufnahmewahrscheinlichkeit hatten Patienten mit den Hauptdiagnosen Subarachnoidalblutung (52 %) oder Hirninfarkt (51 %). Kaum Einfluss auf die Aufnahmewahrscheinlichkeit hatten die Faktoren Alter, Wert des Frührehabilitations-Barthelindex (FRB), Monitorpflicht, Vorhandensein einer Trachealkanüle, Dysphagie, Orientierungs- oder Verhaltensstörung, alle anderen Hauptdiagnosen und Anzahl der Anmeldungen in einer oder mehreren Frührehabilitationskliniken.

Schlussfolgerung Die wohnortnahe NNFR für Patienten aus NDS / HB war in mehr als der Hälfte der Fälle nicht möglich. Die Studie sollte Anlass für eine differenzierte Betrachtung der aktuellen Versorgungsstrukturen im Bereich der NNFR in NDS und HB sein.
Synthesis of Chiral Triazole-Based Halogen Bond Donors
Authors: Kaasik Mikk , Kaabel Sandra , Kriis Kadri , Järving Ivar , Kanger Tõnis
Published: March 2019

The number of applications that use halogen bonding in the fields of self-assembly, supramolecular aggregation, and catalysis is growing. However, the accessibility of chiral halotriazoles shows that there is still a lot more to explore. The simple click-chemistry is applied for the straightforward synthesis of enantiomerically pure mono- and bidentate as well as multifunctional iodotriazole-based XB donors. The methodology is characterized by a wide variability due to easy access of chiral azides.
Child Health: Is It Really Assisted Reproductive Technology that We Need to Be Concerned About?
Authors: Kim Keewan , Purdue-Smithe Alexandra , Bell Griffith , Zolton Jessica , Ghassabian Akhgar , Vafai Yassaman , Robinson Sonia , Mumford Sunni , Yeung Edwina
Published: March 2019

Concerns remain about the health of children conceived by infertility treatment. Studies to date have predominantly not identified substantial long-term health effects after accounting for plurality, which is reassuring given the increasing numbers of children conceived by infertility treatment worldwide. However, as technological advances in treatment arise, ongoing studies remain critical for monitoring health effects. To study whether the techniques used in infertility treatment cause health differences, however, remains challenging due to identification of an appropriate comparison group, heterogeneous treatment, and confounding by the underlying causes of infertility. In fact, the factors that are associated with underlying infertility, including parental obesity and other specific male and female factors, may be important independent factors to consider. This review will summarize key methodological considerations in studying children conceived by infertility treatment including the evidence of associations between underlying infertility factors and child health.
Assisted Reproductive Technologies and the Placenta: Clinical, Morphological, and Molecular Outcomes
Authors: Riesche Laren , Bartolomei Marisa
Published: March 2019

As the biological bridge between mother and fetus, the placenta is not only important for the health of the mother and fetus during pregnancy but it also impacts the lifelong health of the fetus. Assisted reproductive technologies (ARTs) involve procedures and exposures that are not characteristic of in vivo reproduction. Moreover, ART procedures occur when the gametes and embryos are undergoing extensive epigenetic reprogramming. Thus, the oxidative, thermal, and mechanical stress that ART procedures introduce can impact the biological processes of placental growth, development, and function with potentially long-lasting health effects for the offspring. Here, we focus on the placenta and summarize the clinical, morphological, and molecular outcomes of ART. This review highlights that ART procedures have additive effects on placental morphology as well as epigenetic disturbances and provides a foundation for reconceptualizing ART outcomes.
Thermal stability of resistive switching effect in ZnO/BiFeO3 bilayer structure
Authors: Zhang H. Y. , Xiong W. M. , Zhang X. Y. , Wang Biao , Zheng Yue
Published: March 2019

Superior thermal stability of resistive switching performance is essential for resistive random access memory (R-RAM) device with high reliability. Thermal stable resistive switching performance can be achieved in ZnO/BiFeO3 bilayer structure by modifying the interface. The bilayer structure with a distinct interface is fabricated with an optimized annealing process in chemical solution deposition method. This bilayer structure shows a better thermal stability compared to the case with an indistinct interface. Attempt has been made to explain such effects based on conductive filament mechanism. We propose that the confinement of the oxygen vacancies migration at distinct interface could be the reason for the thermal stability. Our results indicate that morphology of interface is an important factor to improve the thermal stability of R-RAM.
Role of time scales and topology on the dynamics of complex networks
Authors: Gupta Kajari , Ambika G.
Published: March 2019

The interplay between time scales and structural properties of complex networks of nonlinear oscillators can generate many interesting phenomena, like amplitude death, cluster synchronization, frequency synchronization, etc. We study the emergence of such phenomena and their transitions by considering a complex network of dynamical systems in which a fraction of systems evolves on a slower time scale on the network. We report the transition to amplitude death for the whole network and the scaling near the transitions as the connectivity pattern changes. We also discuss the suppression and recovery of oscillations and the crossover behavior as the number of slow systems increases. By considering a scale free network of systems with multiple time scales, we study the role of heterogeneity in link structure on dynamical properties and the consequent critical behaviors. In this case with hubs made slow, our main results are the escape time statistics for loss of complete synchrony as the slowness spreads on the network and the self-organization of the whole network to a new frequency synchronized state. Our results have potential applications in biological, physical, and engineering networks consisting of heterogeneous oscillators.
Magnetic properties of “thick” glass-coated Fe-rich microwires
Authors: Corte-León P. , Zhukova V. , Ipatov M. , Blanco J. M. , González J. , Zhukov A.
Published: March 2019

We report on preparation and magnetic properties of Fe71.7B13.4Si11Nb3Ni0.9 glass-coated microwire with metallic nucleus diameter d = 103 μm and total diameter D = 158 μm prepared by Taylor-Ulitovsky method. Amorphous structure of as-prepared microwires is confirmed by X-ray diffraction. As-prepared glass-coated microwires present relatively high GMI effect (about 50%) and relatively low coercivity (about 25 A/m). Additionally, as-prepared sample present rectangular hysteresis loop and fast single domain wall propagation with domain wall mobility of about 11,9 m2/As. After annealing we observed considerable improvement of the GMI ratio (from 50% up to 100%). Observed GMI effect improvement has been attributed to the stresses relaxation. From aforementioned studies we can conclude that the Taylor-Ulitovsky technique allows us to obtain thick ferromagnetic microwires with good magnetic properties and GMI effect suitable for industrial applications.
Development of a water level sensor using magnetostrictive materials
Authors: Yoo JinHyeong , Jones Nicholas J. , Flynn Kyle , Jacobs Rachel
Published: March 2019

In this study, an active-mode water level sensor has been developed to distinguish between the interfaces in large capacity water tanks. The sensor must be robust to withstand forces due to moving water when filling or emptying the tanks, and should be able to work when the water tank is both in motion and still. A Galfenol-brass unimorph beam has been constructed, with Galfenol (an Fe-Ga alloy, magnetostrictive material) as the active layer. The beam is clamped at one end, and, when it is flexed, there will be a stress concentration near the clamped region. This change in stress can be measured by a magnetic field sensor, which can detect local changes in magnetic field. Two magnetic coils are used, one for alternating current (AC) magnetic field generation and the other for measuring the magnetic field response of the beam. The resonance frequency of the beam in air is 248 Hz, and 206 Hz in water. By choosing an operating vibrational frequency of 280 Hz, we can separate the pick-up coil voltage response due to differences in the surrounding environment. The sensor was mounted vertically in a water tank and the system was tested both as the water level increased and decreased, showing a 10% increase from not submerged to fully submerged. The relative sensor response was evaluated from room temperature (25 °C) to 80 °C, showing a 9.1% linear increase in voltage response in water, and 8.2% in air.
Characteristic of high frequency Fe-Si-Cr material for motor application by selective laser melting
Authors: Jhong Kai-Jyun , Chang Tsung-Wei , Lee Wen-Hsi , Tsai Mi-Ching , Jiang I-Hua
Published: March 2019

In this paper, a soft magnetic composite (SMC) material, FeSiCr, is analyzed for its beneficial electromagnetic properties and unique 3D formation capacity, which endows a very high potential to become the material for electric motor fabrication by 3D printing technology adopting high temperature selective laser melting (SLM) process. A microscopic and spectroscopic experiment performed on FeSiCr after SLM process showed that FeO is the oxide layer responsible for the unique advantages of this material. Furthermore, FeSiCr is proved to have lower core loss and eddy current loss at high frequency via the comparison analysis between FeSiCr and silicon steel sheet, a popularly used material for electric motor construction.
Synthesis of γ’-Fe4N powder in liquid nitrogen
Authors: Jiang Yanfeng , Jiang Linxin
Published: March 2019

A novel synthesis approach is developed to prepare nanocrystalline γ’-Fe4N in this paper. High energy cryomilling approach in liquid nitrogen is used to prepare the sample. A FexN amorphous state with a degree of metastable supersaturation of N into Fe is obtained. The crystalline size after higher energy cryomilling approach is characterized to be 40 ∼ 80 nm. A post-annealing among 200 ∼ 300 °C for 10 minutes results in phase transformation from α-iron into γ’-Fe4N. Its magnetic properties and structures are characterized, showing good soft magnetic material with ultralow coercivity (0.7 Oe). It shows high electrical resistivity (375 μΩ·m) at room temperature. The feasibility of the ball milling synthesis approach in liquid nitrogen is verified, suggesting a novel approach for the soft magnetic material preparation.
“Möbius” microring resonator
Authors: Xu Xin-Biao , Shi Lei , Guo Guang-Can , Dong Chun-Hua , Zou Chang-Ling
Published: March 2019

A category of optical microring resonator, which is analogous to the Möbius strip, is proposed. The “Möbius” microring resonator allows the conversion between modes with different polarizations in the ring, and light must circulate two cycles to be converted back to the original polarization status, which is similar to a Möbius strip. This topology structure of polarization makes the free spectral range half of that which corresponds to the cavity round trip. The eigenmodes of this microring are hybridizations of different polarizations, and the breaking of the rotation invariance of the ring makes the transmission related to the polarization of input light and the relative rotation of the cavity. Our work opens the door towards the photonic devices with nontrivial mode topology and provides another way to engineer photonic structures for fundamental studies.
Limit cycles and bifurcations in a nonlinear MEMS resonator with a 1:3 internal resonance
Authors: Houri S. , Hatanaka D. , Asano M. , Ohta R. , Yamaguchi H.
Published: March 2019

This work investigates the behavior of an AlGaAs/GaAs piezoelectric nonlinear MEMS oscillator exhibiting a 1:3 internal resonance. The device is explored in an open-loop configuration, i.e., as a driven resonator, where depending on the drive conditions we observe energy transfer between the first and third modes, and the emergence of supercritical Hopf limit cycles. We examine the dependence of these bifurcations on the oscillator's frequency and amplitude and reproduce the observed behavior using a system of nonlinearly coupled equations which show interesting scaling behavior.
Particle filtering of dynamical networks: Highlighting observability issues
Authors: Montanari Arthur N. , Aguirre Luis A.
Published: March 2019

In a network of high-dimensionality, it is not feasible to measure every single node. Thus, an important goal is to define the optimal choice of sensor nodes that provides a reliable state reconstruction of the network system state-space. This is an observability problem. In this paper, we propose a particle filtering (PF) framework as a way to assess observability properties of a dynamical network, where each node is composed of an individual dynamical system. The PF framework is applied to two benchmarks, networks of Kuramoto and Rössler oscillators, to investigate how the interplay between dynamics and topology impacts the network observability. Based on the numerical results, we conjecture that, when the network nodal dynamics are heterogeneous, better observability is conveyed for sets of sensor nodes that share some dynamical affinity to its neighbourhood. Moreover, we also investigate how the choice of an internal measured variable of a multidimensional sensor node affects the PF performance. The PF framework effectiveness as an observability measure is compared with a well-consolidated nonlinear observability metric for a small network case and some chaotic system benchmarks.
Effect of damping groove on flow dynamics and vibration characteristics of axial piston pump
Authors: Hesheng Tang , Ren Yan , Xiang Jiawei , Guo Cong
Published: March 2019

This paper presents pressure, flow and vibration characteristics of an axial piston pump valve plate with damping grooves. For flow ripple and vibration of the pump reduction, an improved compressible fluid model of axial-piston pump with damping groove is developed to analyze flow dynamics and vibration characteristics. A parametric analysis is performed to analyze the effects of damping groove on the discharge pressure and flow ripples of axial piston pump. The sensitivity of discharge pressure and flow ripple are analyzed to different pressure levels, speeds, and damping groove parameters. The results of pressure ripple and vibration characteristics are validated by experimental test. The experimental and simulation results differ by only approximately 0.75 MPa in the pressure ripple amplitude. The results of the vibration acceleration measurements show that the valve plate with damping groove reduces the vibration level by 0.4 mm/s2 at the rated working condition. It is the effective method that the valve plate parameters are improved to reduce vibration characteristics of axial piston pump.
Direct numerical simulation of spatially developing highly compressible mixing layer: Structural evolution and turbulent statistics
Authors: Zhang Dongdong , Tan Jianguo , Yao Xiao
Published: March 2019

Direct numerical simulation of a spatially developing supersonic mixing layer with a convective Mach number of 1.0 is conducted. The present work focuses on the structural evolution and the turbulent statistics, and both instantaneous and time-averaged data are utilized to obtain further insight into the dynamical behaviors of the flow. The full development process of instability, including the shear action at the flow early stage, the generation of kinds of typical vortex structures in the flow transition region, and the establishment of self-similar turbulence, is clearly presented. The formation and evolution mechanisms of multiple ring-like vortices are reported and analyzed using the Helmholtz first law in compressible mixing layers, and the role they play in the mixing process in the flow transition stage is researched. The mean velocity distribution and the turbulent intensities are found to have close relations with the evolution of the multiple ring-like vortices. The presence of multiple ring-like vortices leads to local strong ejection and sweep regions that create pockets of partially mixed fluid near the tips of the vortices, which contributes much to the huge energy and momentum transfer of the upper and lower streams. Some anisotropy coefficients and turbulent structure parameters are described and analyzed to better reveal the effects of multiple ring-like vortices on flow behaviors. Our results indicate that with the increase in compressibility, though in a fully turbulent region, mixing layer growth and turbulent intensities are both suppressed, the appearance of multiple ring-like vortices and their evolutions can significantly promote mixing in the transition stage, which is usually ignored by previous researchers. Therefore, employing flow control methods to extend the flow transition stage and help sustain multiple ring-like vortices over a longer distance is a possible technique to enhance mixing.
Effect of low hole mobility on the efficiency droop of AlGaN nanowire deep ultraviolet light emitting diodes
Authors: Hai X. , Rashid R. T. , Sadaf S. M. , Mi Z. , Zhao S.
Published: March 2019

Compared to the extensive studies on the efficiency droop of InGaN visible light emitting diodes (LEDs), the efficiency droop of AlGaN deep ultraviolet (UV) LEDs is much less studied. In this context, we discuss the efficiency droop of AlGaN ternary nanowire deep UV LEDs. The device active region consisted of AlGaN double heterojunctions, which were grown by molecular beam epitaxy on silicon substrates. Through detailed analysis of the device optical characteristics under both continuous-wave and pulsed operations, as well as of the electrical characteristics from 293 K to 77 K, it is suggested that the efficiency droop is largely rooted in the low hole mobility, due to the dominant Mg impurity band conduction at room temperature in highly p-doped AlGaN alloys.
Inferring energy incident on sensors in low-intensity surface fires from remotely sensed radiation and using it to predict tree stem injury
Authors: Dickinson Matthew B. , Butler Bret W. , Hudak Andrew T. , Bright Benjamin C. , Kremens Robert L. , Klauberg Carine
Published: March 2019

Remotely sensed radiation, attractive for its spatial and temporal coverage, offers a means of inferring energy deposition in fires (e.g. on soils, fuels and tree stems) but coordinated remote and in situ (in-flame) measurements are lacking. We relate remotely sensed measurements of fire radiative energy density (FRED) from nadir (overhead) radiometers on towers and the Wildfire Airborne Sensor Program (WASP) infrared camera on a piloted, fixed-wing aircraft to energy incident on in situ, horizontally oriented, wide-angle total flux sensors positioned ~0.5m above ground level. Measurements were obtained in non-forested herbaceous and shrub-dominated sites and in (forested) longleaf pine (Pinus palustris Miller) savanna. Using log–log scaling to reveal downward bias, incident energy was positively related to FRED from nadir radiometers (R2=0.47) and WASP (R2=0.50). As a demonstration of how this result could be used to describe ecological effects, we predict stem injury for turkey oak (Quercus laevis Walter), a common tree species at our study site, using incident energy inferred from remotely sensed FRED. On average, larger-diameter stems were expected to be killed in the forested than in the non-forested sites. Though the approach appears promising, challenges remain for remote and in situ measurement.
Fractional coalescent
Authors: Mashayekhi Somayeh , Beerli Peter
Published: March 2019

An approach to the coalescent, the fractional coalescent (

f

-coalescent), is introduced. The derivation is based on the discrete-time Cannings population model in which the variance of the number of offspring depends on the parameter

α

. This additional parameter

α

affects the variability of the patterns of the waiting times; values of

α
<
1

lead to an increase of short time intervals, but occasionally allow for very long time intervals. When

α
=
1

, the

f

-coalescent and the Kingman’s

n

-coalescent are equivalent. The distribution of the time to the most recent common ancestor and the probability that

n

genes descend from

m

ancestral genes in a time interval of length

T

for the

f

-coalescent are derived. The

f

-coalescent has been implemented in the population genetic model inference software M
igrate
. Simulation studies suggest that it is possible to accurately estimate

α

values from data that were generated with known

α

values and that the

f

-coalescent can detect potential environmental heterogeneity within a population. Bayes factor comparisons of simulated data with

α
<
1

and real data (H1N1 influenza and malaria parasites) showed an improved model fit of the

f

-coalescent over the

n

-coalescent. The development of the

f

-coalescent and its inclusion into the inference program M
igrate
facilitates testing for deviations from the

n

-coalescent.
Swimming against the typological tide or paddling along with language change?
Authors: Grossman Eitan , Polis Stéphane
Published: March 2019

It has repeatedly been observed that there is a worldwide preference for suffixes over prefixes. In this article, we argue that universally dispreferred – or rare – structures can and do arise as the result of regular processes of language change, given the right background structures. Specifically, we show that Ancient Egyptian-Coptic undergoes a long-term diachronic macro-change from exhibiting mixed suffixing-prefixing to showing an overwhelming preference for prefixing. The empirical basis for this study is a comparison of ten typologically significant parameters in which prefixing or affixing is potentially at stake, based onDryer’s (2013a)969-language sample. With its extremely high prefixing preference, Coptic belongs to the rare 6% or so of languages that are predominantly prefixing. We argue that each of the micro-changes implicated in this macro-change are better understood in terms of changes at the level of individual constructions, rather than in terms of a broad structural “drift.” Crucially, there is nothing unusual about the actual processes of change themselves.
Four directionalities for grammaticalization
Authors: Company Company Concepción
Published: March 2019

This article offers an analysis and systematization of the relationship between directionality and grammaticalization and develops an innovative proposal regarding a new type of directionality. The article proposes four types of directionality in grammaticalization: A.down, B.up, C.neither down nor up, and D.up and down. The first three types are very well studied, but the last has been overlooked in the theoretical literature. The article analyzes directionality D in depth. It is a directionality that is very similar to a round trip: an up in the cline is followed by a down in the cline. First, the form or construction leaves sentence grammar and enters into periphery grammar, acquiring a new category and a discourse meaning, generally a subjective one; later, the form comes back into sentence grammar, but always re-enters as a different category from the etymological source. This process appears to beround trip directionality. This round trip process constitutes a fourth type of directionality in grammaticalization. Directionality D requires its own status, distinct from the sum of directionalities A and B, due to its specific source and due to the fact that the reinsertion into the sentence grammar is in a specific category. It has its own individual distribution and a characteristic and innovative circular path. The evidence of this directionality presented in this article comes from Spanish, but this path very likely also generalizes to other languages.
The effectiveness of real-time ultrasound visual feedback on tongue movements in L2 pronunciation training
Authors: Antolík Tanja Kocjančič , Pillot-Loiseau Claire , Kamiyama Takeki
Published: March 2019

The purpose of this study was to test the usability of ultrasound as a visual feedback tool in L2 pronunciation training. Six Japanese-speaking learners, aged 28–33 years, participating in a course in French phonetics for L2 learners, took part in the study. Four of them received three individual 45-minute lessons of ultrasound pronunciation training. The other two participants did not. Articulatory and acoustic data of French isolated /y/ and /u/ and Japanese [ɯ] were recorded before and after the ultrasound training, as well as two months later for the learners receiving the training. The analysis of the articulatory data revealed that three speakers with ultrasound feedback improved in the production of the French vowels, the contrast between them, as well as the contrast between the two French vowels and the Japanese [ɯ], suggesting that ultrasound may be a useful tool in second language pronunciation learning.
Learning Korean pronunciation
Authors: Isbell Daniel R. , Park Ok-Sook , Lee Kyujin
Published: March 2019

This study investigated the effects of pronunciation instruction for 36 tertiary learners of Korean in terms of
accentedness, comprehensibility, and phonological error rates while accounting for proficiency (2nd-semester beginners,
4th-semester intermediates), first language background (English, Chinese), and task effects. Participants completed
beginner-appropriate picture description and read-aloud tasks at pretest and posttest. Over eight weeks, a treatment group
received eight hours of instruction targeting segmental and syllable-structure features. Ten Korean NSs judged learner
accentedness and comprehensibility, and learner productions were analyzed for phonological errors. Beginners’ accentedness,
comprehensibility, and error rates improved regardless of receiving instruction. For intermediates, the control group showed no
development in comprehensibility or accentedness, while the treatment group trended toward increased comprehensibility.
Intermediate students showed minimal improvements in phonological error rates. L1 had a negligible impact on accentedness and
comprehensibility, but Chinese-speaking students committed more syllable-structure errors. Associations between phonological
errors and comprehensibility/accentedness varied by outcome task and L1.
Negotiating statist neoliberalism: the political economy of post-revolution Egypt
Authors: Khalil Heba , Dill Brian
Published: March 2019

This article explores the reproduction of Egypt’s post-revolutionary political economy under the military regime. Through an examination of tax and fiscal policy, the authors argue that a strategic wedding of seemingly contradictory state types allows the current regime to create a hybrid they call ‘statist neoliberalism’. The article argues that this hybrid form is not accidental, but is an intentional project that allows the state to sustain neoliberal reforms, whilst maintaining its long-standing control over society and the economy.
THE RELATIONS OF EMBRYONIC TISSUE AND TUMOR IN MIXED GRAFTS
Authors: Rous Peyton
Published: March 2019

In Volume XIII, Number 2, page 247, Fig. 6, lines 3 and 4, for "plate X" read "plate XIII"
Cluster theory of the coherent Satake category
Authors: Cautis Sabin , Williams Harold
Published: March 2019

We study the category of

G
(

O

)

G(\mathcal {O})

-equivariant perverse coherent sheaves on the affine Grassmannian

G
r

G

\mathrm {Gr}_G

. This coherent Satake category is not semisimple and its convolution product is not symmetric, in contrast with the usual constructible Satake category. Instead, we use the Beilinson-Drinfeld Grassmannian to construct renormalized

r
r

-matrices. These are canonical nonzero maps between convolution products which satisfy axioms weaker than those of a braiding.

We also show that the coherent Satake category is rigid, and that together these results strongly constrain its convolution structure. In particular, they can be used to deduce the existence of (categorified) cluster structures. We study the case

G
=
G

L
n

G = GL_n

in detail and prove that the

G

m

\mathbb {G}_m

-equivariant coherent Satake category of

G

L
n

GL_n

is a monoidal categorification of an explicit quantum cluster algebra.

More generally, we construct renormalized

r
r

-matrices in any monoidal category whose product is compatible with an auxiliary chiral category, and explain how the appearance of cluster algebras in 4d

N

=
2

\mathcal {N}=2

field theory may be understood from this point of view.
Symbolic topological dynamics in the circle
Authors: Morales C. , Oh Jumi
Published: March 2019

We explain how dynamical systems with generating partitions are symbolically expansive, namely symbolic counterparts of the expansive ones. Similar ideas allow the notions of symbolic equicontinuity, symbolic distality, symbolic

N
N

-expansivity, and symbolic shadowing property. We analyze dynamical systems with these properties in the circle. Indeed, we show that every symbolically

N
N

-expansive circle homeomorphism has finitely many periodic points. Moreover, if there are no wandering points, then the situation will depend on the rotation number. In the rational case the homeomorphism is symbolically equicontinuous with the symbolic shadowing property and, in the irrational case, the homeomorphism is symbolically expansive, symbolically distal, but not symbolically equicontinuous. We will also introduce a symbolic entropy and study its properties.
A positive lower bound for liminf_{𝑁→∞}∏ᵣ₌₁^{𝑁}|2sin𝜋𝑟𝜑|
Authors: Grepstad Sigrid , Kaltenböck Lisa , Neumüller Mario
Published: March 2019

Nearly 60 years ago, Erdős and Szekeres raised the question of whether

lim inf

N
→
∞

∏

r
=
1

N

|
2
sin
⁡
π
r
α
|

=
0

\begin{equation*} \liminf _{N\to \infty } \prod _{r=1}^N \left | 2\sin \pi r \alpha \right | =0 \end{equation*}

for all irrationals

α
\alpha

. Despite its simple formulation, the question has remained unanswered. It was shown by Lubinsky in 1999 that the answer is yes if

α
\alpha

has unbounded continued fraction coefficients, and he suggested that the answer is yes in general. However, we show in this paper that for the golden ratio

φ
=
(

5

−
1
)

/

2

\varphi =(\sqrt {5}-1)/2

,

lim inf

N
→
∞

∏

r
=
1

N

|
2
sin
⁡
π
r
φ
|

>
0
,

\begin{equation*} \liminf _{N\to \infty } \prod _{r=1}^N \left | 2\sin \pi r \varphi \right | >0 , \end{equation*}

providing a negative answer to this long-standing open problem.
Myosin II governs intracellular pressure and traction by distinct tropomyosin-dependent mechanisms
Authors: Sao Kimheak , Jones Tia M. , Doyle Andrew D. , Maity Debonil , Schevzov Galina , Chen Yun , Gunning Peter W. , Petrie Ryan J.
Published: March 2019

Two-dimensional (2D) substrate rigidity promotes myosin II activity to increase traction force in a process negatively regulated by tropomyosin (Tpm) 2.1. We recently discovered that actomyosin contractility can increase intracellular pressure and switch tumor cells from low-pressure lamellipodia to high-pressure lobopodial protrusions during three-dimensional (3D) migration. However, it remains unclear whether these myosin II–generated cellular forces are produced simultaneously, and by the same molecular machinery. Here we identify Tpm 1.6 as a positive regulator of intracellular pressure and confirm that Tpm 2.1 is a negative regulator of traction force. We find that Tpm 1.6 and 2.1 can control intracellular pressure and traction independently, suggesting these myosin II–dependent forces are generated by distinct mechanisms. Further, these tropomyosin-regulated mechanisms can be integrated to control complex cell behaviors on 2D and in 3D environments.
Inequity in rehabilitation interventions after hip fracture: a systematic review
Authors: Sheehan K J , Fitzgerald L , Hatherley S , Potter C , Ayis S , Martin F C , Gregson C L , Cameron I D , Beaupre L A , Wyatt D , Milton-Cole R , DiGiorgio S , Sackley C
Published: March 2019

Objective

to determine the extent to which equity factors contributed to eligibility criteria of trials of rehabilitation interventions after hip fracture. We define equity factors as those that stratify healthcare opportunities and outcomes.

Design

systematic search of MEDLINE, Embase, CINHAL, PEDro, Open Grey, BASE and ClinicalTrials.gov for randomised controlled trials of rehabilitation interventions after hip fracture published between 1 January 2008 and 30 May 2018. Trials not published in English, secondary prevention or new models of service delivery (e.g. orthogeriatric care pathway) were excluded. Duplicate screening for eligibility, risk of bias (Cochrane Risk of Bias Tool) and data extraction (Cochrane’s PROGRESS-Plus framework).

Results

twenty-three published, eight protocol, four registered ongoing randomised controlled trials (4,449 participants) were identified. A total of 69 equity factors contributed to eligibility criteria of the 35 trials. For more than 50% of trials, potential participants were excluded based on residency in a nursing home, cognitive impairment, mobility/functional impairment, minimum age and/or non-surgical candidacy. Where reported, this equated to the exclusion of 2,383 out of 8,736 (27.3%) potential participants based on equity factors. Residency in a nursing home and cognitive impairment were the main drivers of these exclusions.

Conclusion

the generalisability of trial results to the underlying population of frail older adults is limited. Yet, this is the evidence base underpinning current service design. Future trials should include participants with cognitive impairment and those admitted from nursing homes. For those excluded, an evidence-informed reasoning for the exclusion should be explicitly stated.

PROSPERO

CRD42018085930.
Consequences of intraspecific variation in seed dispersal for plant demography, communities, evolution and global change
Authors: Snell Rebecca S , Beckman Noelle G , Fricke Evan , Loiselle Bette A , Carvalho Carolina S , Jones Landon R , Lichti Nathanael I , Lustenhouwer Nicky , Schreiber Sebastian J , Strickland Christopher , Sullivan Lauren L , Cavazos Brittany R , Giladi Itamar , Hastings Alan , Holbrook Kimberly M , Jongejans Eelke , Kogan Oleg , Montaño-Centellas Flavia , Rudolph Javiera , Rogers Haldre S , Zwolak Rafal , Schupp Eugene W
Published: March 2019

As the single opportunity for plants to move, seed dispersal has an important impact on plant fitness, species distributions and patterns of biodiversity. However, models that predict dynamics such as risk of extinction, range shifts and biodiversity loss tend to rely on the mean value of parameters and rarely incorporate realistic dispersal mechanisms. By focusing on the mean population value, variation among individuals or variability caused by complex spatial and temporal dynamics is ignored. This calls for increased efforts to understand individual variation in dispersal and integrate it more explicitly into population and community models involving dispersal. However, the sources, magnitude and outcomes of intraspecific variation in dispersal are poorly characterized, limiting our understanding of the role of dispersal in mediating the dynamics of communities and their response to global change. In this manuscript, we synthesize recent research that examines the sources of individual variation in dispersal and emphasize its implications for plant fitness, populations and communities. We argue that this intraspecific variation in seed dispersal does not simply add noise to systems, but, in fact, alters dispersal processes and patterns with consequences for demography, communities, evolution and response to anthropogenic changes. We conclude with recommendations for moving this field of research forward.
Frailty and related outcomes in patients undergoing transcatheter valve therapies in a nationwide cohort
Authors: Kundi Harun , Popma Jeffrey J , Reynolds Matthew R , Strom Jordan B , Pinto Duane S , Valsdottir Linda R , Shen Changyu , Choi Eunhee , Yeh Robert W
Published: March 2019

Aims

We sought to identify the prevalence and related outcomes of frail individuals undergoing transcatheter mitral valve repair and transcatheter aortic valve replacement (TAVR).

Methods and results

Patients aged 65 and older were included in the study if they had at least one procedural code for transcatheter mitral valve repair or TAVR between 1 January 2016 and 31 December 2016 in the Centers for Medicare and Medicaid Services Medicare Provider and Review database. The Hospital Frailty Risk Score, an International Classification of Diseases, Tenth Revision (ICD-10) claims-based score, was used to identify frailty and the primary outcome was all-cause 1-year mortality. A total of 3746 (11.6%) patients underwent transcatheter mitral valve repair and 28 531 (88.4%) underwent TAVR. In the transcatheter mitral valve repair and TAVR populations, respectively, there were 1903 (50.8%) and 14 938 (52.4%) patients defined as low risk for frailty (score <5), 1476 (39.4%) and 11 268 (39.5%) defined as intermediate risk (score 5–15), and 367 (9.8%) and 2325 (8.1%) defined as high risk (score >15). One-year mortality was 12.8% in low-risk patients, 29.7% in intermediate-risk patients, and 40.9% in high-risk patients undergoing transcatheter mitral valve repair (log rank P < 0.001). In patients undergoing TAVR, 1-year mortality rates were 7.6% in low-risk patients, 17.6% in intermediate-risk patients, and 30.1% in high-risk patients (log rank P < 0.001).

Conclusions

This study successfully identified individuals at greater risk of short- and long-term mortality after undergoing transcatheter valve therapies in an elderly population in the USA using the ICD-10 claims-based Hospital Frailty Risk Score.
Temporal trends in validated ischaemic stroke hospitalizations in the USA
Authors: Koton Silvia , Wruck Lisa , Quibrera Pedro Miguel , Gottesman Rebecca F , Agarwal Sunil K , Jones Sydney A , Wright Jacqueline D , Shahar Eyal , Coresh Josef , Rosamond Wayne D
Published: March 2019

Background

Accurate assessment of the burden of stroke, a major cause of disability and death, is crucial. We aimed to estimate rates of validated ischaemic stroke hospitalizations in the USA during 1998–2011.

Methods

We used the Atherosclerosis Risk in Communities (ARIC) study cohort’s adjudicated stroke data for participants aged ≥55 years, to construct validation models for each International Classification of Diseases (ICD)-code group and patient covariates. These models were applied to the Nationwide Inpatient Sample (NIS) data to estimate the probability of validated ischaemic stroke for each eligible hospitalization. Rates and trends in NIS using ICD codes vs estimates of validated ischaemic stroke were compared.

Results

After applying validation models, the estimated annual average rate of validated ischaemic stroke hospitalizations in the USA during 1998–2011 was 3.37 [95% confidence interval (CI): 3.31, 3.43) per 1000 person-years. Validated rates declined during 1998–2011 from 4.7/1000 to 2.9/1000; however, the decline was limited to 1998–2007, with no further decline subsequently through 2011. Validation models showed that the false-positive (∼23% of strokes) and false-negative rates of ICD-9-CM codes in primary position for ischaemic stroke approximately cancel. Therefore, estimates of ischaemic stroke hospitalizations did not substantially change after applying validation models.

Conclusions

Overall, ischaemic stroke hospitalization rates in the USA have declined during 1998–2007, but no further decline was observed from 2007 to 2011. Validated ischaemic stroke hospitalizations estimates were similar to published estimates of hospitalizations with ischaemic stroke ICD codes in primary position. Validation of national discharge data using prospective chart review data is important to estimate the accuracy of reported burden of stroke.
Association between maternal shift work and infant neurodevelopmental outcomes: results from the Taiwan Birth Cohort Study with propensity-score-matching analysis
Authors: Wei Chih-Fu , Chen Mei-Huei , Lin Ching-Chun , Guo Yueliang Leon , Lin Shio-Jean , Liao Hua-Fang , Hsieh Wu-Shiun , Chen Pau-Chung
Published: March 2019

Background

Maternal shift work is associated with preterm delivery, small-for-gestational-age new-borns, childhood obesity and future behavioural problems. However, the adverse effects on and interactions of maternal shift work with infant neurodevelopment remain uncertain. Therefore, we examined the associations between maternal-shift-work status and infant neurodevelopmental parameters.

Methods

The Taiwan Birth Cohort Study is a nationwide birth cohort study following representatively sampled mother–infant pairs in 2005. The participants’ development and exposure conditions were assessed by home interviews with structured questionnaires at 6 and 18 months of age. Propensity scores were calculated with predefined covariates for 1:1 matching. Multivariate conditional logistic regression and the Cox proportional-hazards model were used to examine the association between maternal-shift-work status and infant neurodevelopmental-milestone-achievement status.

Results

In this study, 5637 term singletons were included, with 2098 cases selected in the propensity-score-matched subpopulation. Persistent maternal shift work was associated with increased risks of delays in gross-motor neurodevelopmental milestones [aOR = 1.36, 95% confidence interval (CI) = 1.06–1.76 for walking steadily], fine-motor neurodevelopmental milestones (aOR = 1.39, 95% CI = 1.07–1.80 for scribbling) and social neurodevelopmental milestones (aOR = 1.35, 95% CI = 1.03–1.76 for coming when called upon). Moreover, delayed gross-motor and social development were identified in the propensity-score-matched sub-cohort.

Conclusions

This study shows negative associations between maternal shift work and delayed neurodevelopmental-milestone achievement in the gross-motor, fine-motor and social domains at 18 months. Future research is necessary to elucidate the possible underlying mechanisms and long-term health effects.
Using healthcare-seeking behaviour to estimate the number of Nipah outbreaks missed by hospital-based surveillance in Bangladesh
Authors: Hegde Sonia T , Salje Henrik , Sazzad Hossain M S , Hossain M Jahangir , Rahman Mahmudur , Daszak Peter , Klena John D , Nichol Stuart T , Luby Stephen P , Gurley Emily S
Published: March 2019

Background

Understanding the true burden of emergent diseases is critical for assessing public-health impact. However, surveillance often relies on hospital systems that only capture a minority of cases. We use the example of Nipah-virus infection in Bangladesh, which has a high case-fatality ratio and frequent person-to-person transmission, to demonstrate how healthcare-seeking data can estimate true burden.

Methods

We fit logistic-regression models to data from a population-based, healthcare-seeking study of encephalitis cases to characterize the impact of distance and mortality on attending one of three surveillance hospital sites. The resulting estimates of detection probabilities, as a function of distance and outcome, are applied to all observed Nipah outbreaks between 2007 and 2014 to estimate the true burden.

Results

The probability of attending a surveillance hospital fell from 82% for people with fatal encephalitis living 10 km away from a surveillance hospital to 54% at 50 km away. The odds of attending a surveillance hospital are 3.2 (95% confidence interval: 1.6, 6.6) times greater for patients who eventually died (i.e. who were more severely ill) compared with those who survived. Using these probabilities, we estimated that 119 Nipah outbreaks (95% confidence interval: 103, 140)—an average of 15 outbreaks per Nipah season—occurred during 2007–14; 62 (52%) were detected.

Conclusions

Our findings suggest hospital-based surveillance missed nearly half of all Nipah outbreaks. This analytical method allowed us to estimate the underlying burden of disease, which is important for emerging diseases where healthcare access may be limited.
An MLST approach to support tracking of plasmids carrying OXA-48-like carbapenemase
Authors: Brehony Carina , McGrath Elaine , Brennan Wendy , Tuohy Alma , Whyte Thomas , Brisse Sylvain , Maiden Martin , Jolley Keith , Morris Dearbháile , Cormican Martin
Published: March 2019

Objectives

The prevalence of infections caused by OXA-48-like carbapenemase-producing organisms in Ireland has increased dramatically since 2011 and is an urgent public health issue. Genome-based high-resolution genotyping was used to analyse clinical isolates submitted to the Irish Carbapenemase-Producing Enterobacteriaceae Reference Laboratory Service for a 13 month period (2016–17).

Methods

A total of 109 OXA-48-producing non-duplicate clinical isolates from 16 submitting centres were sequenced. Using a gene-by-gene approach, isolate genomes were characterized by MLST and core genome MLST, and the presence of antimicrobial resistance determinants was determined. Reference mapping and a novel plasmid MLST-type approach was applied to determine plasmid background.

Results

The OXA-48-like-producing isolates were Escherichia coli (n = 56), Klebsiella spp. (n = 46) and Enterobacter cloacae (n = 7). Amongst the E. coli isolates there were 37 different STs and amongst the Klebsiella spp. isolates there were 27 different STs. blaOXA-48 was present in 105/109 (96.3%) of isolates. Based on mapping analysis and detection of the pOXA-48 IncL-type plasmid replicon and backbone genes, a pOXA-48-like plasmid was identified in 93/109 isolates (85.3%). The remaining isolates (n = 16; 14.7%) harboured blaOXA-48-like genes in unknown environments. Using a gene-by-gene approach two pOXA-48-like plasmid groups with 2/71 pOXA-48-like locus differences between them were identified.

Conclusions

In Ireland we found a diversity of genotypes associated with OXA-48-like-producing clinical isolates with the IncL pOXA-48 plasmid type predominating as the blaOXA-48 genetic environment. A plasmid MLST approach can rapidly identify plasmids associated with outbreaks and monitor spread of types temporally and geographically.